Evidence for b baryons in Z decays

1992

Abstract In 160 000 hadronic Z decays recorded with the ALEPH detector at LEP, the yields of Λl− and Λl+ combinations have been measured. The observed excess of Λl− over Λl+ of 53±13 is interpreted as evidence for b baryons and their semileptonic decay. Assuming that three body decay processes such as Λ b →Λ c + l − v dominate the semileptonic decay of b baryons, this ex cess corresponds to a product branching ratio BR ( b →Λ b )· BR (Λ b →Λ c + l − v )· BR (Λ c + →ΛX) = (0.95±0.22 ( stat. )±0.21( syst. ))% , where Λb and Λc+ denote the bottom and charm baryons respectively.

Latirismo

1992

Se hac e una revisión bibliográfica de est e cuadro neurotóxico en lo que hac e referencia a datos epidemiológicos, enfatizando los especiale s condicionamientos socioeconómicos y como consecuencia, su condicionada presentación "geográfica". Se estudian los posible s mecanismo s patogénicos, no definitivament e aclarados, y se comentan sus relacione s con otros cuadros neurotóxicos provocados por e l consumo de legumbres. Se dedica un apartado a la utilización de los latirógenos en la preparación de modelos experimentale s diversos en investigación básica. Se aborda el tratamiento considerando las medidas profilácticas a tomar aún conociendo las dificultades de su puesta en práctica y se se…

Crop-water models

1992

International audience

De l'arxiu a les aules: recerca i ensenyament de la història medieval

1992

Les herbicides. Mode d'action et principes d'utilisation

1992

National audience

Les différenciations sociales de carrières scolaires : à quels moments et selon quels mécanismes ?

1992

International audience

Simulation of Models for Isotropic and Anisotropic Orientational Glasses

1992

“Orientational glass” behavior is found when molecular crystals are randomly diluted, and quadrupole moments get frozen by random alignment of the molecules, similar to “spin glass” behavior of randomly diluted magnets. Monte Carlo simulation of lattice models where quadrupole moments interact with nearest neighbor Gaussian coupling is a unique tool to study this behavior. The time-dependent glass order parameter exhibits anomalously slow relaxation, compatible with the Kohlrausch-Williams-Watts (KWW) stretched exponential function. Both isotropic and anisotropic models exhibit in d=2 and d=3 spatial dimensions glass transitions at zero temperature only. While the glass correlation length a…

Normal vs. strike-slip faulting during rift development in East Africa: The Malawi rift

1992

Kinematic analysis of Neogene and Quaternary faults demonstrates that the direction of extension in the Malawi rift rotated from east-northeast to southeast. Rift development commenced with the formation of half-grabens bounded by northwest-, north-, and northeast-striking normal faults. Owing to slightly oblique rifting, the northwest-striking faults in the northernmost rift segment show a small dextral oblique-slip component, whereas north- and northeast-oriented faults in the central part of the rift display a sinistral oblique-slip component. This first event resulted in block faulting and basin subsidence, which is largely responsible for the present-day basin morphology of Lake Malawi…

A Transputer-Based System for Multi-Stroke Character Recognition

1992

A multi-stroke handwritten character recognition system is presented in this paper. A suitable set of Fourier Descriptors is used as features set to describe each stroke. A man-machine interactive algorithm was utilized to accomplish the learning phase and to recognize unknown samples. A PC based prototype was realized at first to test the system. In order to speed up the recognition process, the design and a first prototype of a Transputer-based system have been realized too. Some preliminary experimental results obtained applying these machines to handwritten numerals are reported in the paper.

Espondilolistesis traumática del axis asociada a fractura de odontoides: a propósito de un caso

1992

Se presentan dos casos de espondilolistesis traumática del axis, tipo I de Effendi, asociadas a fractura de odontoides. En ninguno de los casos fue necesario realizar tratamiento quirúrgico, consiguiendo la consolidación de ambas fracturas mediante inmovilización con halo-chaleco. Two new case s of traumatic spondylolisthesis of the axis, Effendi's type I, associated to fracture of the odontoid process are reported. Surgical treatment wa s not necessary in any of the cases. Repair of both fractures wa s adrieved by means of inmovilization with halo-chest orthesis.

Las técnicas dramáticas : procedimiento didáctico para la enseñanza de la lengua y la literatura en la educación secundaria

1992

Structure and thermodynamics in polymer blends. Neutron scattering measurements on blends of poly(methyl methacrylate) and poly(styrene-co-acrylonitr…

1992

Abstract Neutron scattering on polymer blends of deutero-poly(methyl methacrylate) (D-PMMA) and poly(styrene-co-acrylonitrile) with 19 wt% acrylonitrile (PSAN-19) exhibits excess scattering for scattering vectors Q≲0.2 nm−1 if the volume fraction of D-PMMA is less than 0.5 and greater than 0.05. The range of occurrence and the amount of excess scattering depends to a certain degree on the procedure of sample preparation. If the excess scattering is eliminated by linear extrapolation from large to small Q in the Zimm representation, the residual scattering intensity in the small and intermediate Q-range can be interpreted by the mean field approach of de Gennes with a concentration-dependent…

Preismanagement und Marketing Mix-Interaktion

1992

Der Preis sollte nie isoliert, sondern immer im Gesamtzusammenhang mit den anderen Marketinginstrumenten betrachtet und beurteilt werden. Unseren Erfahrungen zufolge denken Manager typischerweise in derartigen Zusammenhangen, also „multi-instrumental“. Konsequenterweise verbinden sie die Variation eines Instrumentes fast immer mit Anderungen bei anderen Instrumenten. Die in der Praxis zu beobachtenden Aktionen umfassen in aller Regel mehrere Marketingparameter (vgl. Peckham 1973, Strang 1976, Carpenter 1987). Typische Beispiele sind: Aktionen des Herstellers: temporare Preissenkung, erhohte/aktionsbezogene Werbung, spezieller Ausendiensteinsatz, geanderte Packung (Grose, Aufdruck o. a.), be…

Survival in extreme dryness and DNA-single-strand breaks.

1992

A wide variety of organisms (the so-called "anhydrobiotes') is able to survive long periods of time in a state of utmost dehydration and can thus survive in extremely dry environments including artificially imposed or space vacuum. Known strategies of survival include the accumulation of certain polyols, especially disaccharides, which help prevent damage to membranes and proteins. Here we report that DNA in vacuum-dried spores is damaged to a very substantial degree by processes leading to DNA strand breaks. Most of these lesions are obviously repaired during germination, but extensive damage to DNA and enzymes after long exposure times (months to years) finally diminish the chances of sur…

Les livres dans les abbayes vosgiennes du Moyen Age

1992

International audience

Pour une histoire nouvelle de la criminalité au 18e siècle

1992

International audience

Distal spleno-renal shunt versus endoscopic sclerotherapy in the prevention of variceal rebleeding

1992

Meta-analysis was used to evaluate 4 clinical trials comparing distal spleno-renal shunt (DSRS) with endoscopic sclerotherapy (EVS) in the prevention of variceal rebleeding: the interval between bleeding and therapy ranges from 100 days. A questionnaire was sent to each author of the published trials concerning methods, definitions and results of the trials in order to obtain more detailed and up-to-date information. The selected end-points for the meta-analysis were: rebleeding, mortality and chronic encephalopathy. Analysis of the results in the questionnaires was made using the method proposed by Collins. The pooled relative risk (i.e. the combined Odds ratio of each trial as an estimate…

Introduction to the Discussion Session on Photo- and Electrodisintegration of the Deuteron

1992

This session is exclusively devoted to the electromagnetic break-up of the deuteron. It reflects the fact that notwithstanding its long history deuteron photo- and electrodisintegration is still an active and interesting field of research (for a recent review on photodisintegration see [1]). The purpose of this introduction is — on the one hand — to put the various contributions to this session into a general perspective and — on the other hand — to supply complimentary material of interesting recent experimental results which is of relevance to the general theme.

Substance P- and calcitonin gene-related peptide-like immunoreactive neurons in the rat trigeminal ganglion — with special reference to meningeal and…

1992

Summary The distribution of perikarya showing substance P- ( SP ) or calcitonin gene-related peptide-like inununoreactivity ( CGRP-LI ) in the rat trigeminal ganglion ( TG ) were investigated by means of immunohistochemical methods. Approximately 50% of the perikarya contain CGRP while SP-Ll was observed in 1/3 of the cells. IR fibres were seen to leave the ganglion via the ophtalmic, maxillary, and mandibular nerves. The combination of peptide histochemistry and retrograde labelling of cells in the ganglion following injection of a fluorescent tracer into the pineal gland reveals that few SP- or CGRP-LI trigeminal neurons innervate the pineal gland. In contrast, the vast majority of perika…

A sensory map of sparkling waters : an application of free-choice profiling method and procustes analysis

1992

Dendrochronologie et architecture monumentale dans le haut Moyen Âge, problèmes spécifiques

1992

catalogue d'exposition G. Lambert, B. Maurice; International audience

Obra dispersa. José Mª Ots Capdequí [Prólogo]

1992

Sobre José María Ots Capdequí

Latvijas, Lietuvas un Igaunijas zinātniskie un populārzinātniskie žurnāli (1918-1940) : izstādes katalogs

1992

A New Type of Artificial Oxygen Carrier: Soluble Hyperpolymeric Haemoglobin with Negligible Oncotic Pressure—Production of Thermally Stable Hyperpoly…

1992

Abastos y defensa de la ciudad de Valencia ante la delicada situación en el ámbito mediterráneo (1552-1585)

1992

Oxygenation of Mammary Tumors: From Isotransplanted Rodent Tumors to Primary Malignancies in Patients*

1992

The role of oxygen in tumor cell proliferation, radiosensitivity, cytotoxicity of anticancer drugs and hyperthermia treatment has been the subject of a series of investigations (for reviews see Hall, 1988; Teicher et al., 1990, Vaupel et al., 1989a; Vaupel, 1990a,b). Despite the apparent importance of tumor oxygenation, data on pO2 values in solid tumors are mostly derived from experiments on rodents which might not necessarily reflect the variability of the clinical situation. Due to feasible techniques available now, considerable advances have been made in the past few years in the assessment of tumor hypoxia in patients (for reviews see Vaupel et al., 1989a; Vaupel, 1990a). The latter in…

Metabolism of phenol in the terrestrial snail Cepaea nemoralis L

1992

1. The metabolism of phenol in the terrestrial snail Cepaea nemoralis was studied after injection into the haemocoel of the dorsolateral foot region. 2. Excreted metabolites, and metabolites extracted from the body, were analysed by h.p.l.c. In addition to phenyl beta-D-glucoside, arbutine (quinol beta-D-glucoside), a new conjugate of phenol, was detected.

Inheritance and other main principles of C++ and other object-oriented languages

1992

Высокочастотные безэлектродные источники света

1992

Aplicaciones de la informática a la investigación en Cirugía Ortopédica y Traumatología

1992

La informática es en la actualidad un medio fundamental en los laboratorios de investigación. La informática desempeña una labor importante en la realización de experimentos (análisis de señales e imágenes), en la valoración analítica de los resultados (estadística, morfometría, espectometría), en el almacenamiento de la información (sistemas de memoria magnética y óptica) y finalmente en la presentación de las conclusiones (impresión laser, diapositivas y video asistido por ordenador). Se presentan las bases teóricas de la informática en el terreno de la investigación y se hace especial mención a los sistemas utilizados en nuestro laboratorio de Ortopedia experimental con objeto de que sir…

Dinámica evolutiva en sistemas territoriales de pequeña empresa : el caso de la región textil de Alcoi-Ontinyent

1992

Importancia del hematoma en las fracturas de los hueso s largos: estudio experimental en ratas

1992

Los autores han estudiado la importancia del hematoma en la consolidación de las fracturas de los hueso s largos. Para ello, han realizado un estudio experimental en 50 ratas Wistar, en las cuales se producía una fractura a nivel de sus tibias, siendo estabilizadas posteriormente, mediante agujas intramedulares. El hematoma era aspirado del foco de fractura en el miembro derecho, mientras que el miembro izquierdo servía como control. Los animale s fueron sacrificados tras diferente s periodos de tiempo, y el callo formado en las diferente s muestras ha sido analizado en relación a los aspectos radiológico y microscópico. Se pudo observar un predominio del tejido fibroso en el miembro contro…

Las universidades españolas del siglo XIX y las ciencias

1992

Thanatophoric dysplasia in monozygotic twins discordant for cloverleaf skull: Prenatal diagnosis, clinical and pathological findings

1992

We present male monozygotic twins with thanatophoric dysplasia (TD) type I concordant for long bone abnormalities and discordant for cloverleaf skull. The twins were the product of the second pregnancy of unrelated parents, with advanced paternal age. Prenatal diagnosis and postmortem examination showed severe rhizomelic shortness of limbs, bowing of the long bones with "telephone-receiver" femora in both twins, and cloverleaf skull and hydrocephalus in one of them. It is now accepted that most of cases of TD, such as in the present report, represent an autosomal dominant mutation with a high new mutations rate.

Insatisfacción profesional en la enfermería: estudio piloto

1992

Insatisfacción profesional en la enfermería: estudio piloto

Aloinjerto de matriz ósea descalcificada versus injerto autólogo en la reparación de defectos óseos segmentarios masivos. : Estudio experimental

1992

Se compara la capacidad regenerativa del aloinjerto de matriz ósea descalcificada con el tradicional injerto óseo autólogo en el tratamiento de defectos osteoperiósticos de 4-5 cm, de longitud provocados experimentalment e a nivel diafisario en fémur ovino. Para este experimento, se emplearon 18 corderos de raza churra esquelé- ticament e maduros. En 8 animales, la reconstrucción del defecto diafisario se intentó mediant e el aport e aloinjerto fragmentado de matriz óse a descalcificada. En otros 6 animales, el defecto se rellenó con injerto corticoesponjoso autólogo, también fragmentado. La estabilización ósea se realizó por medio de un fijador externo. Tras efectuar estudio s radiológicos…