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1.
Eur Phys J A Hadron Nucl ; 58(12): 239, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36514540

RESUMEN

Neutron capture reaction cross sections on 74 Ge are of importance to determine 74 Ge production during the astrophysical slow neutron capture process. We present new resonance data on 74 Ge( n , γ ) reactions below 70 keV neutron energy. We calculate Maxwellian averaged cross sections, combining our data below 70 keV with evaluated cross sections at higher neutron energies. Our stellar cross sections are in agreement with a previous activation measurement performed at Forschungszentrum Karlsruhe by Marganiec et al., once their data has been re-normalised to account for an update in the reference cross section used in that experiment.

2.
Phys Rev Lett ; 125(14): 142701, 2020 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-33064503

RESUMEN

The neutron capture cross sections of several unstable nuclides acting as branching points in the s process are crucial for stellar nucleosynthesis studies. The unstable ^{171}Tm (t_{1/2}=1.92 yr) is part of the branching around mass A∼170 but its neutron capture cross section as a function of the neutron energy is not known to date. In this work, following the production for the first time of more than 5 mg of ^{171}Tm at the high-flux reactor Institut Laue-Langevin in France, a sample was produced at the Paul Scherrer Institute in Switzerland. Two complementary experiments were carried out at the neutron time-of-flight facility (n_TOF) at CERN in Switzerland and at the SARAF liquid lithium target facility at Soreq Nuclear Research Center in Israel by time of flight and activation, respectively. The result of the time-of-flight experiment consists of the first ever set of resonance parameters and the corresponding average resonance parameters, allowing us to make an estimation of the Maxwellian-averaged cross sections (MACS) by extrapolation. The activation measurement provides a direct and more precise measurement of the MACS at 30 keV: 384(40) mb, with which the estimation from the n_TOF data agree at the limit of 1 standard deviation. This value is 2.6 times lower than the JEFF-3.3 and ENDF/B-VIII evaluations, 25% lower than that of the Bao et al. compilation, and 1.6 times larger than the value recommended in the KADoNiS (v1) database, based on the only previous experiment. Our result affects the nucleosynthesis at the A∼170 branching, namely, the ^{171}Yb abundance increases in the material lost by asymptotic giant branch stars, providing a better match to the available pre-solar SiC grain measurements compared to the calculations based on the current JEFF-3.3 model-based evaluation.

3.
Phys Rev Lett ; 121(4): 042701, 2018 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-30095928

RESUMEN

We report on the measurement of the ^{7}Be(n,p)^{7}Li cross section from thermal to approximately 325 keV neutron energy, performed in the high-flux experimental area (EAR2) of the n_TOF facility at CERN. This reaction plays a key role in the lithium yield of the big bang nucleosynthesis (BBN) for standard cosmology. The only two previous time-of-flight measurements performed on this reaction did not cover the energy window of interest for BBN, and they showed a large discrepancy between each other. The measurement was performed with a Si telescope and a high-purity sample produced by implantation of a ^{7}Be ion beam at the ISOLDE facility at CERN. While a significantly higher cross section is found at low energy, relative to current evaluations, in the region of BBN interest, the present results are consistent with the values inferred from the time-reversal ^{7}Li(p,n)^{7}Be reaction, thus yielding only a relatively minor improvement on the so-called cosmological lithium problem. The relevance of these results on the near-threshold neutron production in the p+^{7}Li reaction is also discussed.

4.
Schweiz Arch Tierheilkd ; 159(7): 381-386, 2017 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-28703708

RESUMEN

INTRODUCTION: The correct oral treatment of pigs in groups is a demanding procedure. Prescriptions of medicated feed for groups larger than 20 pigs have to be made on official forms submitted to veterinary authorities. In this work, we evaluated 1'126 such forms for the years 2010-2011 to calculate the therapeutic intensity for piglets and fatteners at farm level in the canton of Lucerne. This analysis shows that essential data were often difficult to obtain and that the provided information did not always allow for plausible intensity calculations. In total, 654 and 424 kg of antimicrobials were prescribed during the 2 years under investigation. For the years 2010 and 2011, the calculated median intensities were 43.5 and 32.5 treated animals per 1'000 individuals per day (PIDvet) for piglets and 75.9 and 64.8 for fatteners. PIDvet for the whole populations of piglets and fatteners treated with medicated feed delivered from feed mills were 37.51 resp. 84.44 in the year 2011.


INTRODUCTION: L'administration orale d'antibiotiques à des groupes d'animaux est exigeante. Toute prescription destinée à plus de 20 porcs à traiter doit, légalement, être faite au moyen d'un formulaire d'ordonnance officiel. Dans le présent article, on étudie l'intensité des traitements chez des porcelets et des porcs d'engraissement dans des exploitations du canton de Lucerne durant les années 2010­2011 sur la base de 1'126 formulaires. Cette analyse montre que des données importantes pour le calcul sont souvent difficiles à obtenir et que des calculs plausibles sont partiellement impossibles. Au total 654 respectivement 424 kg d'antibiotiques ont été prescrits durant ces deux ans. L'intensité médiane des traitements pour 2010 et 2011 s'élevait à 43.5 et 32.5 animaux en traitement pour 1000 individus à une date donnée (PIDvet) pour les porcelets et à 75.9 et 64.8 pour les porcs d'engraissement. Pour l'ensemble de la population de porcelets et de porcs d'engraissement, des valeurs de PIDvet de 37.51 respectivement 84.44 pour l'application en 2011 d'aliments médicamenteux produits par les moulins agricoles, ont été calculées.


Asunto(s)
Antiinfecciosos/administración & dosificación , Enfermedades de los Porcinos/tratamiento farmacológico , Drogas Veterinarias/administración & dosificación , Alimentación Animal , Animales , Porcinos , Enfermedades de los Porcinos/prevención & control
5.
Phys Rev Lett ; 117(15): 152701, 2016 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-27768364

RESUMEN

The energy-dependent cross section of the ^{7}Be(n,α)^{4}He reaction, of interest for the so-called cosmological lithium problem in big bang nucleosynthesis, has been measured for the first time from 10 meV to 10 keV neutron energy. The challenges posed by the short half-life of ^{7}Be and by the low reaction cross section have been overcome at n_TOF thanks to an unprecedented combination of the extremely high luminosity and good resolution of the neutron beam in the new experimental area (EAR2) of the n_TOF facility at CERN, the availability of a sufficient amount of chemically pure ^{7}Be, and a specifically designed experimental setup. Coincidences between the two alpha particles have been recorded in two Si-^{7}Be-Si arrays placed directly in the neutron beam. The present results are consistent, at thermal neutron energy, with the only previous measurement performed in the 1960s at a nuclear reactor. The energy dependence reported here clearly indicates the inadequacy of the cross section estimates currently used in BBN calculations. Although new measurements at higher neutron energy may still be needed, the n_TOF results hint at a minor role of this reaction in BBN, leaving the long-standing cosmological lithium problem unsolved.

6.
Biomater Sci ; 4(7): 1092-9, 2016 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-27138623

RESUMEN

A novel, ultrasound based approach for the dynamic stimulation and promotion of tissue healing processes employing surface acoustic waves (SAW) on a chip is presented for the example of osteoblast-like SaOs-2 cells. In our investigations, we directly irradiate cells with SAW on a SiO2 covered piezoelectric LiNbO3 substrate. Observing the temporal evolution of cell growth and migration and comparing non-irradiated to irradiated areas on the chip, we find that the SAW-treated cells exhibit a significantly increased migration as compared to the control samples. Apart from quantifying our experimental findings on the cell migration stimulation, we also demonstrate the full bio compatibility and bio functionality of our SAW technique by using LDH assays. We safely exclude parasitic side effects such as a SAW related increased substrate temperature or nutrient flow by thoroughly monitoring the temperature and the flow field using infrared microscopy and micro particle image velocimetry. Our results show that the SAW induced dynamic mechanical and electrical stimulation obviously directly promotes the cell growth. We conclude that this stimulation method offers a powerful platform for future medical treatment, e.g. being implemented as a implantable biochip with wireless extra-corporal power supply to treat deeper tissue.


Asunto(s)
Técnicas de Cultivo de Célula , Movimiento Celular , Ondas Ultrasónicas , Cicatrización de Heridas , Línea Celular Tumoral , Estimulación Eléctrica , Diseño de Equipo , Humanos , Niobio/química , Óxidos/química , Dióxido de Silicio/química , Vibración
7.
J Dent Res ; 94(5): 690-6, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25691071

RESUMEN

Local anesthesia has made dental treatment more comfortable since 1884, but little is known about associated brain mechanisms. Functional magnetic resonance imaging is a modern neuroimaging tool widely used for investigating human brain activity related to sensory perceptions, including pain. Most brain regions that respond to experimental noxious stimuli have recently been found to react not only to nociception alone, but also to visual, auditory, and other stimuli. Thus, presumed functional attributions have come under scrutiny regarding selective pain processing in the brain. Evidently, innovative approaches are warranted to identify cerebral regions that are nociceptive specific. In this study, we aimed at circumventing known methodological confounders by applying a novel paradigm in 14 volunteers: rather than varying the intensity and thus the salience of painful stimuli, we applied repetitive noxious dental stimuli at constant intensity to the left mandibular canine. During the functional magnetic resonance imaging paradigm, we suppressed the nociceptive barrage by a mental nerve block. Brain activity before and after injection of 4% articaine was compared intraindividually on a group level. Dental pain extinction was observed to correspond to activity reduction in a discrete region of the left posterior insular cortex. These results confirm previous reports demonstrating that direct electrical stimulation of this brain region-but not of others-evokes bodily pain sensations. Hence, our investigation adds further evidence to the notion that the posterior insula plays a unique role in nociceptive processing.


Asunto(s)
Encéfalo/fisiopatología , Odontalgia/tratamiento farmacológico , Adulto , Anestésicos Locales/administración & dosificación , Carticaína/administración & dosificación , Cerebelo/fisiopatología , Corteza Cerebral/fisiopatología , Mentón/inervación , Diente Canino/efectos de los fármacos , Diente Canino/inervación , Estimulación Eléctrica , Giro del Cíngulo/fisiopatología , Hipocampo/fisiopatología , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Bloqueo Nervioso/métodos , Vías Nerviosas/fisiopatología , Nocicepción/efectos de los fármacos , Nocicepción/fisiología , Dolor/fisiopatología , Lóbulo Parietal/fisiopatología , Corteza Prefrontal/fisiopatología , Lóbulo Temporal/fisiopatología , Tálamo/fisiopatología , Odontalgia/fisiopatología , Corteza Visual/fisiopatología , Adulto Joven
8.
Eur J Pain ; 17(9): 1374-84, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23468076

RESUMEN

BACKGROUND: Fibromyalgia syndrome (FMS) is frequently associated with psychiatric conditions, particularly anxiety. Deficits in contingency learning during fear conditioning have been hypothesized to increase anxiety and, consequently, pain sensation in susceptible individuals. The goal of this study was to examine the relationship between contingency learning and pain experience in subjects with FMS and rheumatoid arthritis (RA). METHODS: Fourteen female FMS subjects, 14 age-matched female RA subjects and 14 age-matched female healthy controls (HCs) were included in a fear-conditioning experiment. The conditioned stimulus (CS) consisted of visual signs, the unconditioned stimulus (US) of thermal stimuli. CS- predicted low-temperature exposure (US), while CS+ was followed by low or high temperature. RESULTS: In the FMS group, only 50% of the subjects were aware of the US-CS contingency, whereas 86% of the RA subjects and all of the HCs were aware of the contingency. CS+ induced more anxiety than CS- in RA subjects and HCs. As expected, low-temperature exposure was experienced as less painful after CS- than after CS+ in these subjects. FMS subjects did not show such adaptive conditioning. The effects of the type of CS on heart rate changes were significant in the HCs and the aware FMS subjects, but not in the unaware FMS subjects. CONCLUSIONS: Contingency learning deficits represent a potentially promising and specific, but largely unstudied, psychopathological factor in FMS. Deficits in contingency learning may increase anxiety and, consequently, pain sensation. These findings have the potential to contribute to the development of novel therapeutic approaches for FMS.


Asunto(s)
Concienciación/fisiología , Condicionamiento Clásico/fisiología , Miedo/psicología , Fibromialgia/psicología , Adulto , Femenino , Respuesta Galvánica de la Piel , Humanos , Persona de Mediana Edad
9.
Phys Rev Lett ; 110(2): 022501, 2013 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-23383895

RESUMEN

The 63Ni(n,γ) cross section has been measured for the first time at the neutron time-of-flight facility n_TOF at CERN from thermal neutron energies up to 200 keV. In total, capture kernels of 12 (new) resonances were determined. Maxwellian averaged cross sections were calculated for thermal energies from kT=5-100 keV with uncertainties around 20%. Stellar model calculations for a 25M⊙ star show that the new data have a significant effect on the s-process production of 63Cu, 64Ni, and 64Zn in massive stars, allowing stronger constraints on the Cu yields from explosive nucleosynthesis in the subsequent supernova.

11.
J Dent Res ; 91(2): 156-60, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22157099

RESUMEN

Identification of brain regions that differentially respond to pain intensity may improve our understanding of trigeminally mediated nociception. This report analyzed cortical responses to painless and painful electrical stimulation of a right human maxillary canine tooth. Functional magnetic resonance images were obtained during the application of five graded stimulus strengths, from below, at, and above the individually determined pain thresholds. Study participants reported each stimulus on a visual rating scale with respect to evoked sensation. Based on hemodynamic responses of all pooled stimuli, a cerebral network was identified that largely corresponds to the known lateral and medial nociceptive system. Further analysis of the five graded stimulus strengths revealed positive linear correlations for the anterior insula bilaterally, the contralateral (left) anterior mid-cingulate, as well as contralateral (left) pregenual cingulate cortices. Cerebral toothache intensity coding on a group level can thus be attributed to specific subregions within the cortical pain network.


Asunto(s)
Encéfalo/fisiología , Umbral del Dolor/fisiología , Odontalgia/fisiopatología , Adulto , Amígdala del Cerebelo/fisiología , Tronco Encefálico/fisiología , Cerebelo/fisiología , Corteza Cerebral/fisiología , Diente Canino/inervación , Imagen Eco-Planar/métodos , Estimulación Eléctrica , Lóbulo Frontal/fisiología , Giro del Cíngulo/fisiología , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Corteza Motora/fisiología , Nocicepción/fisiología , Dolor Nociceptivo/fisiopatología , Lóbulo Occipital/fisiología , Lóbulo Parietal/fisiología , Putamen/fisiología , Umbral Sensorial/fisiología , Lóbulo Temporal/fisiología , Tálamo/fisiología , Nervio Trigémino/fisiología , Adulto Joven
12.
Arq. bras. med. vet. zootec ; 63(2): 508-510, abr. 2011. ilus
Artículo en Portugués | LILACS | ID: lil-591148

RESUMEN

Vector potential of ants in mechanic dissemination of helminthes in a cat rescue center was analyzed in this study. Ants walking over cat's food and feces were collected and conditioned in distilled water. Cat feces were collected too. Ants were identified and the water where they were conditioned was observed on optic microscope. It was made the simple sedimentation technique to analyze feces. The results show that ants species Pheidole and Paratrechina can be potential vectors of nematode eggs, mainly Ascaridida, Toxocaridae.


Asunto(s)
Animales , Artrópodos/clasificación , Gatos/clasificación , Hormigas , Helmintos/parasitología
13.
Eur Radiol ; 21(4): 807-15, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20890705

RESUMEN

OBJECTIVES: To evaluate whether induced dental pain leads to quantitative changes in brain metabolites within the left insular cortex after stimulation of the right maxillary canine and to examine whether these metabolic changes and the subjective pain intensity perception correlate. METHODS: Ten male volunteers were included in the pain group and compared with a control group of 10 other healthy volunteers. The pain group received a total of 87-92 electrically induced pain stimuli over 15 min to the right maxillary canine tooth. Contemporaneously, they evaluated the subjective pain intensity of every stimulus using an analogue scale. Neurotransmitter changes within the left insular cortex were evaluated by MR spectroscopy. RESULTS: Significant metabolic changes in glutamine (+55.1%), glutamine/glutamate (+16.4%) and myo-inositol (-9.7%) were documented during pain stimulation. Furthermore, there was a significant negative correlation between the subjective pain intensity perception and the metabolic levels of Glx, Gln, glutamate and N-acetyl aspartate. CONCLUSION: The insular cortex is a metabolically active region in the processing of acute dental pain. Induced dental pain leads to quantitative changes in brain metabolites within the left insular cortex resulting in significant alterations in metabolites. Negative correlation between subjective pain intensity rating and specific metabolites could be observed.


Asunto(s)
Espectroscopía de Resonancia Magnética/métodos , Dolor/patología , Nervio Trigémino/patología , Adulto , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Corteza Cerebral/patología , Electrodos , Femenino , Ácido Glutámico/metabolismo , Glutamina/metabolismo , Humanos , Inositol/metabolismo , Masculino , Persona de Mediana Edad , Modelos Anatómicos , Neurotransmisores/metabolismo , Estudios Prospectivos , Protones , Enfermedades Dentales/patología
14.
Eur J Oral Sci ; 117(1): 27-33, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19196315

RESUMEN

For identical diagnoses in the trigeminal innervation territory, individual differences have been clinically observed among the symptoms reported, such as dysesthesia and pain. Different subjective perceptions of unpleasantness and pain intensity may have different cortical substrates. The aim of this study was to identify brain areas in which activation depends on the subjective perception (intensity and unpleasantness) of electric dental stimulation. Electrical stimuli of increasing intensity were applied to maxillary canines in 14 healthy volunteers. Ratings for stimulus intensity and unpleasantness perceived across the stimulation session were reported postscan on 11-point numerical scales. The rating values were then included as covariates in the functional magnetic resonance imaging (fMRI) group analysis. Interindividual differences of intensity ratings were reflected in differential activity of the following brain areas: superior parietal lobule, superior temporal gyrus/anterior insula, inferior and middle temporal gyrus, lingual gyrus, anterior cingulate, and caudate nucleus. Differences related to unpleasantness ratings were reflected in the lingual gyrus. In conclusion, differences of perceived intensity between individuals are reflected in the differential activity of a set of brain areas distinct from those regions, reflecting rating differences of unpleasantness.


Asunto(s)
Mapeo Encefálico , Corteza Cerebral/fisiología , Diente Canino/inervación , Vías Nerviosas/fisiología , Sensación/fisiología , Adulto , Estimulación Eléctrica , Femenino , Humanos , Masculino , Maxilar , Persona de Mediana Edad , Valores de Referencia , Nervio Trigémino/fisiología
15.
Mult Scler ; 14(6): 830-6, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18535018

RESUMEN

BACKGROUND: Binding antibodies (BAB) against interferon-beta (IFNbeta) are often determined as screening assays before performing an expensive and elaborate neutralizing antibody (NAB) test. METHODS: In this study, we compared four BAB tests, a western blot (WB), a direct binding enzyme-linked immunosorbent assay (ELISA) (dELISA), a capture ELISA (cELISA), and a commercial enzyme immuno-assay (EIA) in 325 multiple sclerosis patients with and without neutralizing antibodies to evaluate the sensitivity and specificity to detect NAB by receiver operating characteristics analysis. RESULTS: The area under the curve (AUC) values were 0.907 for the dELISA, 0.925 for the cELISA, and 0.776 for the EIA (P < 0.0001 for all). At a sensitivity of 95%, the specificity was approximately 30% in the dELISA, 55% in the cELISA, and 13% in the EIA. The WB as a qualitative BAB detection method had a given sensitivity of 97% and a specificity of 55%. There was a strong and significant correlation between high NAB titers (>500 neutralizing units [NU]) and titers obtained by all quantitative BAB assays. However, low to medium NAB titers (20-500 NU) did not significantly correlate with BAB titers. CONCLUSION: We conclude that the cELISA seems to be most suitable for NAB screening, but BAB titers cannot reliably predict NAB titers.


Asunto(s)
Anticuerpos/aislamiento & purificación , Ensayo de Inmunoadsorción Enzimática/normas , Interferón beta/inmunología , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Esclerosis Múltiple Recurrente-Remitente/inmunología , Western Blotting/normas , Línea Celular Tumoral , Ensayo de Inmunoadsorción Enzimática/métodos , Humanos , Inmunoensayo/normas , Técnicas In Vitro , Neoplasias Pulmonares , Tamizaje Masivo , Pruebas de Neutralización , Curva ROC , Juego de Reactivos para Diagnóstico/normas , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
16.
Radiat Prot Dosimetry ; 115(1-4): 470-4, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16381769

RESUMEN

The LHC will require an extremely powerful and unprecedented collimation system. As approximately 30% of the LHC beam is lost in the cleaning insertions, these will become some of the most radioactive locations around the entire LHC ring. Thus, remanent dose rates to be expected during later repair or maintenance interventions must be considered in the design phase itself. As a consequence, the beam cleaning insertions form a unique test bed for a recently developed approach to calculate remanent dose rates. A set of simulations, different in complexity, is used in order to evaluate methods for the estimation of remanent dose rates. The scope, as well as the restrictions, of the omega-factor method are shown and compared with the explicit simulation approach. The latter is then used to calculate remanent dose rates in the beam cleaning insertions. Furthermore, a detailed example for maintenance dose planning is given.


Asunto(s)
Arquitectura y Construcción de Instituciones de Salud/métodos , Exposición Profesional/análisis , Aceleradores de Partículas/instrumentación , Monitoreo de Radiación/métodos , Protección Radiológica/instrumentación , Medición de Riesgo/métodos , Simulación por Computador , Diseño Asistido por Computadora , Relación Dosis-Respuesta en la Radiación , Diseño de Equipo , Análisis de Falla de Equipo , Transferencia Lineal de Energía , Modelos Teóricos , Neutrones , Protones , Dosis de Radiación , Protección Radiológica/métodos , Factores de Riesgo , Suiza
17.
Radiat Prot Dosimetry ; 116(1-4 Pt 2): 6-11, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16604585

RESUMEN

Samples of materials which will be used in the LHC machine for shielding and construction components were irradiated in the stray radiation field of the CERN-EU high-energy reference field facility. After irradiation, the specific activities induced in the various samples were analysed with a high-precision gamma spectrometer at various cooling times, allowing identification of isotopes with a wide range of half-lives. Furthermore, the irradiation experiment was simulated in detail with the FLUKA Monte Carlo code. A comparison of measured and calculated specific activities shows good agreement, supporting the use of FLUKA for estimating the level of induced activity in the LHC.


Asunto(s)
Materiales de Construcción/análisis , Transferencia Lineal de Energía , Modelos Teóricos , Protección Radiológica/instrumentación , Protección Radiológica/métodos , Radioisótopos/análisis , Radiometría/métodos , Benchmarking/métodos , Simulación por Computador , Materiales de Construcción/normas , Ensayo de Materiales/métodos , Ensayo de Materiales/normas , Método de Montecarlo , Aceleradores de Partículas/instrumentación , Dosis de Radiación , Protección Radiológica/normas , Radiometría/instrumentación , Radiometría/normas , Reproducibilidad de los Resultados , Dispersión de Radiación , Sensibilidad y Especificidad , Suiza
18.
Radiat Prot Dosimetry ; 116(1-4 Pt 2): 12-5, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16604586

RESUMEN

A new method to estimate remanent dose rates, to be used with the Monte Carlo code FLUKA, was benchmarked against measurements from an experiment that was performed at the CERN-EU high-energy reference field facility. An extensive collection of samples of different materials were placed downstream of, and laterally to, a copper target, intercepting a positively charged mixed hadron beam with a momentum of 120 GeV c(-1). Emphasis was put on the reduction of uncertainties by taking measures such as careful monitoring of the irradiation parameters, using different instruments to measure dose rates, adopting detailed elemental analyses of the irradiated materials and making detailed simulations of the irradiation experiment. The measured and calculated dose rates are in good agreement.


Asunto(s)
Materiales de Construcción/análisis , Transferencia Lineal de Energía , Modelos Teóricos , Protección Radiológica/instrumentación , Protección Radiológica/métodos , Radioisótopos/análisis , Radiometría/métodos , Benchmarking/métodos , Simulación por Computador , Materiales de Construcción/normas , Ensayo de Materiales/métodos , Ensayo de Materiales/normas , Método de Montecarlo , Aceleradores de Partículas/instrumentación , Dosis de Radiación , Protección Radiológica/normas , Radiometría/instrumentación , Radiometría/normas , Reproducibilidad de los Resultados , Dispersión de Radiación , Sensibilidad y Especificidad , Suiza
19.
Schweiz Arch Tierheilkd ; 142(11): 639-42, 2000 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-11103616

RESUMEN

This report describes the findings in a four-year-old Toggenburg goat with demodicosis. The skin had multifocal nodules, which were approximately 5 mm in diameter and contained thick yellow exsudate. Microscopic examination of the exsudate revealed numerous Demodex caprae. The goat was clipped and treated topically every five to seven days for a total of 12 treatments with a 1:100 dilution of amitraz (Ectodex, Hoechst Roussel Vet). The treatment resulted in a marked decrease in the number of skin nodules. However, new nodules appeared after treatment was discontinued and complete clinical cure was not achieved.


Asunto(s)
Enfermedades de las Cabras , Infestaciones por Ácaros/veterinaria , Administración Tópica , Animales , Enfermedades de las Cabras/tratamiento farmacológico , Enfermedades de las Cabras/patología , Cabras , Insecticidas/administración & dosificación , Insecticidas/uso terapéutico , Infestaciones por Ácaros/tratamiento farmacológico , Infestaciones por Ácaros/patología , Ácaros/clasificación , Piel/parasitología , Toluidinas/administración & dosificación , Toluidinas/uso terapéutico
20.
Wien Klin Wochenschr ; 108(9): 262-6, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8686318

RESUMEN

Proximal selective vagotomy (PSV) is an effective, definitive therapy for peptic ulcer disease of the duodenum. Long-term studies have shown that ulcer recurrence occurs in less than 10% of patients if the operation is performed by an experienced surgeon. Since PSV does not influence gastric emptying, side effects such as diarrhea, gastric stasis or the dumping syndrome are rare. Due to this favorable experience, PSV is our preferred technique for the laparoscopic approach to peptic ulcer disease. We have performed this operation in 13 patients. Indications were chronic duodenal ulceration unresponsive to medical therapy, chronic duodenal ulceration combined with reflux esophagitis, and reflux esophagitis due to gastric acid hypersecretion. In patients with reflux esophagitis PSV was performed in addition to an antireflux procedure. Laparoscopic PSV can be performed more accurately than the open procedure since it allows for better visualization with less possibility of missing small vagal connections to the parietal cells such as the 'criminal nerve'. The median duration of operation was 3 hours. There were no serious peri- or postoperative complications. The median time of postoperative hospital stay was 3 days. During the median follow-up of 27 months no recurrence of duodenal or esophageal ulceration was encountered and none of the patients complained of epigastric pain, diarrhea or dumping symptoms.


Asunto(s)
Úlcera Duodenal/cirugía , Esofagitis Péptica/cirugía , Laparoscopios , Vagotomía Gástrica Proximal/instrumentación , Adulto , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Resultado del Tratamiento
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