RESUMEN
A precision measurement by the Alpha Magnetic Spectrometer on the International Space Station of the positron fraction in primary cosmic rays in the energy range from 0.5 to 350 GeV based on 6.8 × 10(6) positron and electron events is presented. The very accurate data show that the positron fraction is steadily increasing from 10 to â¼ 250 GeV, but, from 20 to 250 GeV, the slope decreases by an order of magnitude. The positron fraction spectrum shows no fine structure, and the positron to electron ratio shows no observable anisotropy. Together, these features show the existence of new physical phenomena.
RESUMEN
The aim of this study was to define if the alterations in sensory modalities could be a predictive factor in the prognostic recovery of the ION. Ten patients that had suffered facial trauma, associated with sensitivity alterations of the ION were evaluated prospectively. Touch detection thresholds (TD) were measured using Von Frey's filaments aesthesiometer. A warm/cold discrimination (W/C) was also done to the patients, on the same areas. The patients were examined in both sides of the face, using the non-traumatized side as control. The tests were done before surgery and several times postoperatively. For statistical analysis of the results, the two-sample t test was used. A significant difference (P < 0.0001) in the mean tactile recovery time between the areas without thermal sensitivity before surgery and those with normal thermal sensitivity before surgery was observed. Therefore, we propose that during the preoperative examination, the surgeon examines the thermal discrimination in order to establish prognosis and approximate recovery times.
Asunto(s)
Fracturas Maxilares/complicaciones , Órbita/inervación , Trastornos de la Sensación/etiología , Fracturas Cigomáticas/complicaciones , Adulto , Mejilla/inervación , Frío , Párpados/inervación , Femenino , Estudios de Seguimiento , Predicción , Encía/inervación , Calor , Humanos , Labio/inervación , Masculino , Fracturas Maxilares/cirugía , Nariz/inervación , Pronóstico , Estudios Prospectivos , Recuperación de la Función/fisiología , Umbral Sensorial/fisiología , Diente/inervación , Tacto/fisiología , Fracturas Cigomáticas/cirugíaRESUMEN
In this paper we analyze the seismicity along the Apennines in order to relate the seismicity pattern to the seismogenic environment and to the active tectonic processes. The analysis of crustal and subcrustal seismicity show that the northern and southern Apennines are characterized by two distinct patterns of seismicity. These two domains are separated by two important lithological discontinuities (the Ancona - Anzio and the Ortona - Roccamonfina lines). The seismicity along the Apennines is mainly concentrated in a narrow belt running along the chain, with an evident geometrical offset which corresponds to the Ancona-Anzio line. We discuss these observations considering both the seismological evidence and the present tectonic regime in which the earthquakes occur. We focus on the southern Apennines, where the largest earthquakes (6 ó M ó 7.0) have occurred. We analyze the main features of some recent seismic sequences in order to discuss the seismicity patterns in terms of the hypothesis of segmentation of the southern Apennine seismogenic belt. This work aims to be a preliminary contributions to the important goals of understanding the spatial and temporal patterns of seismicity and of identifying active faults
Asunto(s)
Terremotos , GeologíaRESUMEN
A method based on ion-pair reversed-phase high-performance liquid chromatography with detection at four wavelengths between 400 and 600 nm is reported for the separation and identification of the most common synthetic colour additives in cosmetic products. All the dyes generally employed in the U.S.A. and almost all those in current use in cosmetics in the European Community have been taken into account. The chromatography was performed on a C8 bonded silica packed column, with a 60-min gradient changing from 10 to 95% acetonitrile in water containing 10(-2) M sodium perchlorate (pH 3.0) as mobile phase (flow-rate 2.5 ml/min). Detection limits are in the range 20-100 ng for all dyes investigated. The method has been applied to the analysis of commercial lipsticks.
Asunto(s)
Colorantes/análisis , Cosméticos/análisis , Cromatografía Líquida de Alta Presión , Espectrofotometría UltravioletaRESUMEN
This investigation examined the role of the right hemisphere in language expression. Three groups of 12 subjects each--right CVAs, left CVAs, and controls--performed convergent and divergent language tasks of naming, function, and connected speech. For all convergent tasks and for number of words, number of message units, and fluency in divergent connected speech, controls surpassed both brain-damaged groups, who performed similarly. For the other divergent tasks, controls were superior to the brain-damaged groups, but the right CVAs outperformed the left CVAs. In general, verbal expression problems of right-hemisphere-damaged patients were almost as severe as those of left-hemisphere-damaged patients.
Asunto(s)
Trastornos Cerebrovasculares/psicología , Dominancia Cerebral/fisiología , Conducta Verbal/fisiología , Adulto , Anciano , Corteza Cerebral/patología , Trastornos Cerebrovasculares/patología , Humanos , Pruebas del Lenguaje , Persona de Mediana Edad , PsicolingüísticaRESUMEN
The purpose of this study was to investigate the perceptual confusions individuals experience while listening to the speech of laryngectomized persons who used electrolarynges. Six talkers generated speech samples using two different models of electrolarynges. Intelligibility was evaluated from phonetic transcriptions of the speech samples. Confusion matrices were generated from the transcriptions. Talkers varied considerably in their intelligibility, but there was little difference in intelligibility for a given talker using either model of electrolarynx. The perceptual confusions revealed that most errors occurred on the voicing feature.
Asunto(s)
Laringectomía , Laringe Artificial , Medición de la Producción del Habla , Voz Alaríngea , Humanos , Masculino , Persona de Mediana Edad , Fonación , Fonética , Inteligibilidad del Habla , Calidad de la VozRESUMEN
This article presents a framework for the cognitive analysis of number processing and calculation. Within this framework the primary objective is the development of a model that is sufficiently detailed to serve as a basis for explaining the number-processing/calculation performance of both normal and cognitively impaired subjects. First a general model of the cognitive mechanisms for number processing and calculation is outlined. It is shown that patterns of impairments observed in brain-damaged patients support the major assumptions of the model and that the model provides a theoretically motivated framework for interpreting the deficits. A single case is then discussed in some detail, to demonstrate that through detailed analyses of impaired performance the preliminary model can be elaborated to specify not only the general architecture of the number-processing and calculation systems, but also the inner workings of specific components and the consequences of damage to these components. The article concludes with a discussion of several general issues arising from the presented arguments.
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Afasia/psicología , Daño Encefálico Crónico/psicología , Trastornos del Conocimiento/psicología , Anomia/psicología , Dislexia Adquirida/psicología , Humanos , Recuerdo Mental , SemánticaAsunto(s)
Cosméticos/análisis , Parabenos , Excipientes Farmacéuticos/análisis , Conservadores Farmacéuticos/análisis , Benzoatos/análisis , Ácido Benzoico , Cromatografía Líquida de Alta Presión/métodos , Hidroxibenzoatos/análisis , Indicadores y Reactivos , Jabones/análisis , Ácido Sórbico/análisisRESUMEN
A case study is reported of an aphasic patient with fluent speech and markedly superior comprehension of written vs. spoken words. Results of extensive testing supported the hypothesis that the patient suffers from a phonological processing deficit that affects performance in all tasks that require the generation of a phonological code. This selective deficit is interpreted as the underlying cause of diverse symptoms such as asyntactic comprehension of written sentences, the commission of spelling errors in writing, and the production of literal paraphasias and neologisms in spontaneous speech. Alternative possibilities for the classification of this patient are discussed.
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Afasia/diagnóstico , Trastornos de la Percepción Auditiva/diagnóstico , Trastornos de la Percepción/diagnóstico , Percepción del Habla , Adulto , Anomia/diagnóstico , Afasia de Wernicke/diagnóstico , Infarto Cerebral/diagnóstico , Humanos , Masculino , Recuerdo Mental , Pruebas Neuropsicológicas , Reconocimiento Visual de Modelos , Fonética , Lectura , Semántica , Tomografía Computarizada por Rayos XAsunto(s)
Displasia Fibrosa Ósea/patología , Displasia Fibrosa Monostótica/patología , Enfermedades Maxilomandibulares/patología , Adolescente , Adulto , Niño , Diagnóstico Diferencial , Femenino , Displasia Fibrosa Monostótica/diagnóstico por imagen , Humanos , Enfermedades Maxilomandibulares/diagnóstico por imagen , Neoplasias Maxilomandibulares/diagnóstico por imagen , Neoplasias Maxilomandibulares/patología , Masculino , Persona de Mediana Edad , Radiografía , Estudios RetrospectivosAsunto(s)
Afasia de Wernicke/diagnóstico , Afasia/diagnóstico , Percepción del Habla , Medición de la Producción del Habla , Trastornos Cerebrovasculares/complicaciones , Humanos , Conducta Imitativa , Masculino , Recuerdo Mental , Persona de Mediana Edad , Pruebas Neuropsicológicas , Fonética , Lectura , Conducta VerbalRESUMEN
Four aphasic patients were tested in several tasks to determine their ability to use syntactic information. Two patients classified as Broca's aphasics and presenting markedly different levels of severity of aphasia were deficient in their ability to use syntactic information in sentence comprehension and construction. It is argued that the syndrome of Broca's aphasia undermines patients' ability to perform the syntactic analyses that are necessary to understand and to produce sentences in both language modalities. A third patient was a conduction aphasic who presented a pattern of sentence comprehension similar to the Broca patient, but produced no other evidence of syntactic impairment. The argument is advanced that the conduction patient's apparently selective impairment of syntactic processing in comprehension is actually a reflection of a severe auditory-verbal short-term memory deficit. The fourth patient was classified as a mildly-impaired Wernicke's aphasic, who presented no evidence of a selective disturbance of syntactic processing abilities. These results are interpreted as support for the hypothesis that the syndrome of Broca's aphasia results from an impairment to the syntactic component of the language processing system.