Searching for an invisibly decaying Higgs boson in e+ e-, e gamma and gamma gamma collisions

1994

Higgs bosons can have a substantial ``invisible'' branching ratio in many extensions of the Standard Model, such as models where the Higgs bosons decay predominantly into light or massless weakly interacting Goldstone bosons. In this work, we examine the production mechanisms and backgrounds for invisibly decaying Higgs bosons at the Next Linear e+e− Collider operating in the modes e+e−, eγ, and γγ. We demonstrate that such machine is much more efficient to survey for invisibly decaying Higgs bosons than the Large Hadron Collider at CERN.

Closedness of Star Products and Cohomologies

1994

We first review the introduction of star products in connection with deformations of Poisson brackets and the various cohomologies that are related to them. Then we concentrate on what we have called “closed star products” and their relations with cyclic cohomology and index theorems. Finally we shall explain how quantum groups, especially in their recent topological form, are in essence examples of star products.

Integrating the Kadomtsev-Petviashvili Equation in the 1+3 Dimensions VIA the Generalised Monge-Ampère Equation: An Example of Conditioned Painlevé T…

1994

Crises de l'éducation en Afrique : éléments de diagnostic

1994

International audience; C'est aujourd'hui devenu un lieu commun de décrire la situation éducative de l'Afrique subsaharienne comme un univers de désolation. Il est vrai que les problèmes rencontrés par les systèmes éducatifs de la région sont immenses, mais il convient d'éviter les jugements trop généraux, car tous les problèmes habituellement évoqués n'ont pas le même degré de gravité et ils touchent les pays de la région de manière inégalement sévère. Les analyses et commentaires qui vont suivre portent sur quarante-sept pays de l'Afrique subsaharienne, soit la quasi-totalité de la région considérée, y compris, pour la première fois dans les synthèses relatives à cette région, l'Afrique d…

Le mobilier métallique

1994

International audience

Plasma Proteins, Yolk Proteins and Metal-Binding Proteins

1994

The extracellular fluid of the metazoans is not only a transport vehicle but also, for the majority of the body’s cells, their growth environment. Proteins play an important role here, providing colloid-osmotic pressure and acting as buffers. The most important parameter in this respect is their concentration which, depending upon the species, the developmental stage and the physiological conditions, can vary from less than 1 to more than 200 mg/ml (Table 5.1). In addition to these general functions, individual plasma proteins have various specific roles, e.g. in the transport of substances, in defence reactions, in blood clotting or in the solution of clots. At least in the case of the mor…

APPLICATION OF 3‐D FINITE DIFFERENCE METHOD FOR INDUCTANCE CALCULATION OF AIR‐CORE COILS SYSTEM

1994

The paper deals with the inductance calculation of air‐core coils system by means of 3‐D analysis of magnetic field of the coils with rectangular cross‐section. The possibility of mutual and self‐inductance calculation is presented. For magnetic field calculation, the Finite Difference Method with application of fast calculating procedures was applied. The method of calculation has been verified by experiments. The obtained difference between calculating and measurement results is equal to a few percent. The computer program is usefull especially for asymmetrical configuration of the coils.

Survival and prognostic factors in 366 patients with compensated cirrhosis type B: a multicenter study.

1994

A multicenter longitudinal study was performed to assess the survival of hepatitis B surface antigen positive compensated cirrhosis, primarily in relation to hepatitis B virus replication and hepatitis delta virus infection, and to construct a prognostic index based on entry characteristics. This cohort study involved nine university medical centers in Europe. Three hundred and sixty-six Caucasian HBsAg positive patients with cirrhosis who had never had clinical manifestations of hepatic decompensation were enrolled and followed for a mean period of 72 months (6 to 202 months). Inclusion criteria were biopsy-proven cirrhosis, information on serum hepatitis B e antigen and antibody to hepati…

Development of the UV/ion shields for the Advanced X-ray Astrophysics Facility high-resolution camera (AXAF HRC)

1994

The Advanced X-ray Astrophysics Facility (AXAF) is a major NASA space observatory (launch 1998). One of its two focal plane detectors is the High Resolution Camera (HRC) assembly consisting of two microchannel plate (MCP) based detectors. Key components of the two HRC detectors are UV/Ion shields consisting of metalized sub-micron plastic membranes, designed to prevent UV light and low energy charged particles from reaching the detectors' sensitive surfaces. We discuss the design issues and present results of recent measurements and tests. Soft X-ray/UV transmission measurements have been conducted at the Space Science Laboratory (SSL), University of California at Berkeley, and at the Osser…

Arte mueble de la España mediterránea : Breve síntesis y algunas consideraciones teóricas

1994

En este trabajo se analiza el arte mueble de/Mediterráneo español, basándose especialmente en la colección de plaquetas de El Parpalló. El estudio detallado de los motivos artísticos y su correlación estratigráfica revela algunas diferencias cronológicas en un marco de evolución continua. Conceptos tradicionales, como el de “Provincia Mediterránea‘~ son revisados a la luz de nuevos enfoques teóricosy empíricos. Portable art of Mediterranean Spain is analyzed in this paper with special reference (o the more than five thousand decoratedplaquettesfrom El Parpalló. A detailed study of artistic mot¡fs and stratigraphy reveals some chronological differences inside a frame of continous evolution. …

Comercio internacional, regiones, desarrollo y subdesarrollo en Europa: un debate sobre el modelo de Historia económica bajomedieval

1994

Cotilos roscado y atornillado recubiertos de hidroxiapatita: estudio comparativo

1994

Se estudian 122 cotilos recubiertos de hidroxiapatita, 45 roscados y 77 atornillados, con un seguimiento medio de 3,8 años. La valoración clínica se hizo según el protocolo de Johnston comparando el estado previo y el actual, obteniendo un 93 % de excelentes y buenos resultados en los cotilos roscados y un 83 % con los atornillados. El cotilo roscado ofreció mejores puntuaciones en las necrosis avasculares (p<0,01) y artrosis primarias (p<0,05). El resultado clínico fue mejor en la artrosis primaria que en los recambios (p<0,05) y las artropatías inflamatorias (p<0,01). No se evidenciaron aflojamientos, encontrándose como única diferencia la posición más horizontal de los implantes roscados…

Estimation de la densité de la mesure spectrale mixte pour un processus symétrique stable strictement stationnaire

1994

International audience

Effects of Extracellular Acidosis on Glial Cell Intracellular pH: Evidence for a Glial Spatial H+-Buffering Mechanism?

1994

Acidosis and in particular lactacidosis from anaerobic metabolism are considered of primary significance among the consequences of cerebral ischemia, seizures,, and head injury (Siesjo 1981). A marked decrease in brain tissue pH has been demonstrated in cerebral ischemia - even more so in hyperglycemic subjects - where lactic acid may accumulate to 20–30 mM and higher concentrations (Rehncrona et al. 1980; Katsura et al. 1991). Tissue pH may drop to pH 5.5 (Chopp et al. 1988). In consequence, acidosis has since long been suspected as a mediator of brain damage (Siesjo 1981).

Group O(4) in the Nuclear IBA Model

1994

The group O(4) is established as a link in the group chains of the interacting-boson model (IBA) of nuclear structure. It is obtained as a subgroup of O(5) by excluding the m = 0 component of the d boson. Since only the third component of the angular momentum is then conserved, O(4) symmetry is limited to intrinsic states. No O(3) can be sandwiched between this O(4) and the physical O(2). Branching rules are derived for groups U(4), O(4) and O(2). The dynamic-symmetry contributions of O(4) and U(4) to the energy are given. The structure \(O\left( 4 \right) \approx O\left( 3 \right) \times O\left( 3 \right) \supset O\left( 3 \right)\)is established

Überlieferungs- und Verständnisprobleme im medizinischen Latein des frühen Mittelalters

1994

L'A. tente de saisir dans quelle mesure le latin utilise dans les traites de medecine du Moyen Age etait un moyen de communication insuffisant, quels facteurs peuvent expliquer cet echec et quels efforts ont ete effectues par les savants de l'epoque pour restaurer le sens, tentatives echouant souvent a cause de l'absence de dictionnaires

Bone density of the calcaneus and fractures in 75- and 80-year-old men and women

1994

Bone mineral density of the calcaneus in relation to fractures was studied both retrospectively and prospectively among the 75- and 80-year-old men and women resident in the city of Jyväskylä, Finland, in 1989 and 1990, respectively. The bone measurements were performed at the calcaneus by 125I-photon absorption. Retrospective fracture (RF) history after age 50 was collected by questionnaire and interview, and reported fractures were checked from medical records. In the retrospective study, in the 75-year-olds a fracture was found in 22% (n = 22) of men and in 45% (n = 84) of women. The corresponding figures for the 80-year-olds were 16% (n = 9) and 35% (n = 48). Over half of the fractures …

Numerical methods to compute sentinels for parabolic systems with an application to source terms identification

1994

We apply the method of sentinels to the identification of source terms in parabolic systems. We present two numerical approaches; the first one is based on the solution of an optimal control problem, and the second one is based on the solution of a linear system of equations. In numerical experiments, we compare these approaches in terms of accuracy and computational cost.

La buena letra

1994

Progetto di risalita meccanica a San Marino; motto:Filù, Amore mio

1994

Tècnica, història i discurs en el pensament d'Emanuele Severino

1994

“Love in Black and White: A Comparative Study of Samuel Selvon and Frantz Fanon”

1994

International audience

Organometallic complexes with biological molecules II. Synthesis, solid-state characterization andin vivo Cytotoxicity of Diorganotin(IV)chloro and T…

1994

Several new diorganotin(IV)chloro and triorganotin(IV)chloro penicillin G derivatives have been prepared. The isolated compounds showed 1:1 stoichiometry, with formulae R2SnClpenG and R3SnClpenGNa, respectively (penG− = penicillin G− = 4- thia - 1 - azabicyclo[3.2.0]heptane-2-carboxylate, 3,3-dimethyl-7-oxo-6-(2-phenylacet-amido) anion; R = Me, Bu, Ph). The coordination environment around the the tin(IV) atom, in all of the complexes, was trigonal bipyramidal. Penicillin G behaved as a monoanionic, bismonodentate ligand in R2SnClpenG through the β-lactamic carbonyl and unidentate ester-type carboxylate anion, and as unidentate through the β-lactamic carbonyl in R3SnClpenGNa, as inferred on …

Monadic second-order logic over pictures and recognizability by tiling systems

1994

We show that a set of pictures (rectangular arrays of symbols) is recognized by a finite tiling system if and only if it is definable in existential monadic second-order logic. As a consequence, finite tiling systems constitute a notion of recognizability over two-dimensional inputs which at the same time generalizes finite-state recognizability over strings and matches a natural logic. The proof is based on the Ehrenfeucht-FraIsse technique for first-order logic and an implementation of “threshold counting” within tiling systems.

Transfusion-associated graft-versus-host disease-report of two further cases with an immunohistochemical analysis

1994

Summary Transfusion-associated graft-vs.-host disease (tGVHD) is a severe disease usually affecting immunocompromised hosts with haematological neoplasia. Two patients with acute leukaemia are reported, who developed fatal tGVHD after blood transfusions. Intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1) and endothelial leucocyte adhesion molecule 1 (ELAM-1) expression and the CD4/CD8 ratio were assessed in lesional skin. ICAM-1 was strongly expressed on epidermal keratinocytes and endothelial cells (EC) and correlated with HLA-DR staining. VCAM-1 was strongly expressed on EC in the superficial dermal vessels. ELAM-1 stained weakly on EC in some of the su…

Le site protohistorique d'Acy-Romance (Ardennes), 2 : Les nécropoles dans leur contexte régional

1994

Un tast dels vocabularis bilingües valencians actuals

1994

By means of a choice of seventy words, this work shows the lexical richness and the degree of acceptance of the guidelines –defined in the Diccionari General de Llengua Catalana by Pompeu Fabra– regulating nine bilingual Valencian/Castilian and Castilian/Valencian vocabularies published between 1972 and 1993.

Critical Exponents and Randomness in SrTiO3 : Ca

1994

Since its discovery, the SrTiO3: Ca system is known to exhibit a number of features which were thought to arise from an impurity induced disorder. Non-linear dielectric measurements are used to obtain a more quantitative insight into this disorder. For 0.001 < xCa < 0.05, it is found that the non-linear susceptibility diverges at low temperatures. This is similar to what was previously reported in the dielectric random system KTaO3: Na. A method is proposed to quantify the contribution of the disorder to the non-linearities. It is found that the deviation from a true ferroelectric behaviour is not enough to call the low-temperature phase of SrTiO3: Ca a glass one. The maximum non-linearity …

Influence of the polymerization step alone on oxygen affinity and cooperativity during production of hyperpolymers from native hemoglobins with cross…

1994

The aim of this study was to find out how the polymerization per se changes oxygen affinity (P50) and cooperativity (n50) of various soluble huge hyperpolymers prepared from native hemoglobins by crosslinking. Increase of cooperativity would be expected considering natural hemoglobin networks. Those hyperpolymers with molecular weights of some 10(6) g/mol are candidates for artificial oxygen-carrying blood additives rather than volume substitutes. Human and bovine hemoglobin reacted with several crosslinkers (2,5-diisothiocyanatobenzenesulfonate (DIBS); 4,4'-diisothiocyanatostilbene-2, 2'-disulfonate (DIDS); 1,3-butadiene diepoxide (BUDE); glutaraldehyde (GDA)) in concentrated (case 1) and …

Improved measurements of cross sections and asymmetries at the Z0 resonance

1994

During the 1992 running period of the LEP e+e- collider, the DELPHI experiment accumulated approximately 24 pb-1 of data at the Z0 peak. The decays into hadrons and charged leptons have been analysed to give values for the cross sections and leptonic forward-backward asymmetries which are significantly improved with respect to those previously published by the DELPHI collaboration. Incorporating these new data, more precise values for the Z0 resonance parameters are obtained from model-independent fits. The results are interpreted within the framework of the Standard Model, yielding for the top quark mass m(t) = 157(-48)+36(expt.)-20(+19)(Higgs) GeV, and for the effective mixing angle sin2 …

El paper de València en la transició demogràfica al País Valencià (1860-1930)

1994

Concomitancias entre la pintura de Salvador Soria Zapater y la musica de Francisco Llacer Pla: Espacios sugerentes

1994

El artículo, tras introducirnos brevemente en las figuras de Salvador Soria Zapater y de Francisco Llacer Pla, nos da las claves de la obra "Espacios sugerentes", opus 43 de Francisco Llacer Pla, inspirada en la homonima de Salvador Soria. (F.D.)

Early dynamic interactions between Fusarium oxysporum f.sp. lini and the roots of Linum usitatissimum as revealed by transgenic GUS-marked hyphae

1994

International audience

Osteitis condensante de clavícula

1994

La osteítis condensante de clavícula es una lesión ósea infrecuente, benigna y de etiología desconocida. Se caracteriza por esclerosis densa y homogénea de la porción infero-medial clavicular con obliteración de la cavidad medular sin afectación de la articulación esternoclavicular. Hasta ahora sólo se había descrito en mujeres, en el presente trabajo presentamos un caso en un paciente varón. Se discute el diagnóstico diferencial con otras entidades que producen afectación similar y proponemos la TC como método diagnóstico de elección, defendiendo el tratamiento conservador. Condensing osteitis of the clavicle is a benign and uncommon bone lesion of unknown cause, characterized by homogeneo…

Selbstorganisationen urbaner Strukturen

1994

International audience; Ungeplante Siedlungen und großstädtische Agglomerationen Städte sind Gebilde, die in ihrer Komplexität als Ganzes nicht planbar sind. Der strukturtheoretische Ansatz des SFB 230 ermöglicht durch die weitgehende Abstraktion die systematische Beschreibung der Morphogense großstädtischer Agglomerationen. Diese wertneutrale Vorgehensweise erlaubt es ohne Heranziehung oberflächlicher Biologismen sich mit kulturübergreifenden Eigenschaften moderner Städte auseinanderzusetzen. In diesem Sinne wird Stadtplanung verstanden als die Schaffung geeigneter Rahmenbedingungen für die eigendynamische Entwicklung von unterschiedlichen städtischen Kulturen.

Monte Carlo simulation of alpha spectra in low-geometry measurements

1994

Abstract Monte Carlo simulation of alpha spectra obtained with semiconductor detectors in low-geometry has been developed. The proposed method reproduces adequately experimental spectra of alpha emitters by taking into account the energy losses and trajectory changes of alpha particles as consequences of their interactions in the source, backing and detector.