Adsorption of phenol on formaldehyde-pretreated Pinus pinaster bark: equilibrium and kinetics.

This work studies phenol adsorption on Pinus pinaster bark that has been previously treated with formaldehyde in acid medium. The influence of several variables such as solid/liquid ratio, pH and initial concentration of phenol in the solution on the adsorption capacity of the bark has been analysed. A kinetic model based on phenol diffusion within the pores of the adsorbent was in agreement with the results obtained for high initial concentrations of phenol, allowing the determination of diffusion coefficients. Adsorption equilibrium data were fitted by the Freundlich and BET isotherms. From their parameters phenol adsorption capacity and intensity, as well as the specific surface (BET) of the adsorbent, were determined.

Medida de la inteligibilidad en el habla disártrica / Intelligibility measure in dysarthric speech

El término disartria designa un conjunto de alteraciones del habla causadas por una lesión neurológica. Se trata del trastorno adquirido del habla más frecuente, por ello, la medida de la inteligibilidad en los pacientes disártricos es muy importante tanto para el diagnóstico clínico como para la investigación de la disartria. Sin embargo, una medida objetiva y fiable de la inteligibilidad es difícil al tratarse de una magnitud relativa dependiente de variables concretas del proceso de comunicación. En este trabajo se efectúa una revisión del concepto de inteligibilidad y de los principales procedimientos de medida aplicados para el habla disártrica (escalas de evaluación y tests de identificación). Los autores defienden la necesidad de tests estandarizados que proporcionen no sólo un índice general de gravedad, sino que analicen también los contrastes foneticoacústicos vulnerados en cada caso, en línea con el test para el inglés (Kent, Weismer, Kent y Rosenbeck, 1989). En términos ideales, un test de este tipo debería ser capaz de identificar las principales razones que causan el déficit de inteligibilidad y suministrar información útil para el tratamiento logopédico (AU)

[A rare neurologically originated speech disorder: foreign accent syndrome]. / Una rara alteración del habla de origen neurológico: el sindrome del acento extranjero.

INTRODUCTION: Foreign accent syndrome (FAS) is an unusual neurological speech disorder documented in not more than twenty specific studies. As a consequence of a cerebral mainly subcortical injury, the patient s speech is foreign sounding to native listeners. As subject cannot avoid this foreign accent, and given its abrupt emergence, this disorder usually involves emotional consequences by loss of identity and of belonging to a speech community. CASE REPORT: In this paper, a case from Castellón de la Plana (Spain) is presented with a injury in right basal ganglia and the literature about this topic is revised. CONCLUSIONS: From the available data, we describe the main characteristics of the syndrome and discuss the possible role of basal ganglia

Una rara alteración del habla de origen neurológico: el síndrome del acento extranjero / A rare neurologically originated speech disorder: foreign accent syndrome

Introducción. El síndrome del acento extranjero (FAS, del inglés Foreign Accent Syndrome) es un raro trastorno del habla, de origen neurológico, documentado en no más de 20 estudios específicos. A consecuencia de una lesión cerebral, principalmente subcortical, el paciente habla su lengua materna como lo haría una persona extranjera, y suena con `acento' extranjero a oídos de los oyentes nativos. Este efecto es inevitable para el propio sujeto y, por su brusca aparición, suele tener implicaciones emocionales relacionadas con la pérdida de identidad personal y del sentido de pertenencia a una comunidad parlante. Caso clínico. En este artículo se presenta un caso de la ciudad de Castellón de la Plana, con una lesión en los ganglios basales derechos y se revisa la bibliografía científica disponible sobre este síndrome. Conclusiones. A la luz de los datos se hace una síntesis de sus principales características y se plantea una posible explicación teórica asentada en el papel de los GB del cerebro (AU)

Introduction. Foreign accent syndrome (FAS) is an unusual neurological speech disorder documented in not more than twenty specific studies. As a consequence of a cerebral –mainly subcortical– injury, the patient’s speech is foreign-sounding to native listeners. As subject cannot avoid this foreign accent, and given its abrupt emergence, this disorder usually involves emotional consequences by loss of identity and of belonging to a speech community. Case report. In this paper, a case from Castellón de la Plana (Spain) is presented with a injury in right basal ganglia and the literature about this topic is revised. Conclusions. From the available data, we describe the main characteristics of the syndrome and discuss the possible role of basal ganglia (AU)

Effect of veneer side wettability on bonding quality of Eucalyptus globulus plywoods prepared using a tannin-phenol-formaldehyde adhesive.

The influence of rotary peeling on the different behaviour of tight and loose sides of Eucalyptus globulus veneers has been studied. The presence of lathe checks on the loose sides favours wettability, the contact angle decreasing more rapidly on these sides than on tight sides. Additionally, pine bark tannins improved wettability due to their surfactant character. Bonding quality tests carried out on plywoods prepared using a tannin-phenol-formaldehyde adhesive showed that fracture almost invariably occurred in a glue line with at least one loose side, where wood failure appeared. This behaviour, confirmed by analysing the glue lines by means of fluorescence microscopy, was due to the large surface alterations of the loose sides which reduced mechanical strength but allowed greater penetration of the adhesive giving rise to high wood failure.

Removal of cadmium and mercury ions from aqueous solution by sorption on treated Pinus pinaster bark: kinetics and isotherms.

Formaldehyde pretreated Pinus pinaster bark was used to sorb Cd2+ and Hg2+ from aqueous solutions. The sorption kinetics showed hyperbolic dependence of the proportion of cation adsorbed on time, and the sorption isotherms were satisfactorily fitted by Freundlich equations, with k and n values showing Hg2+ to be more efficiently sorbed than Cd2+. Except for low cation concentrations, for which sorption was practically total at all initial pH > or = 6, sorption increased in this range, in keeping with a mechanism based on ion exchange with the hydroxyl protons of ring B of the procyanidin units of the tannins in the bark.

Preliminary studies on TCF bleaching of Pinus pinaster acetosolv pulps.

Oxygen pre-treatment of Pinus pinaster acetosolv pulps has been studied as a first step towards TCF bleaching. Using a 2(3) factorial design, the influence of temperature (80-120 degrees C), time (1-2 h) and NaOH concentration (1.5-3%) on pulp yield in the oxygen stage, chemical composition and physical properties of the pulps obtained was studied. Pulps pre-bleached with oxygen in the conditions selected as optimal (80 degrees C, 1 h with 2.25% NaOH) have been bleached with TCF sequences which included stages with hydrogen peroxide or hydrogen peroxide-oxygen under pressure. Even if high degrees of delignification were reached, with a reduction in Kappa number up to 95% and without important loss of viscosity, the carbohydrates degradation, especially hemicelluloses in the acetic acid delignification, reduces the strength potential of the pulps.

Acoustical analysis of Spanish vowels produced by laryngectomized subjects.

The purpose of this study was to describe the acoustic characteristics of Spanish vowels in subjects who had undergone a total laryngectomy and to compare the results with those obtained in a control group of subjects who spoke normally. Our results are discussed in relation to those obtained in previous studies with English-speaking laryngectomized patients. The comparison between English and Spanish, which diFfer widely in the size of their vowel inventories, will help us to determine specific or universal vowel production characteristics in these patients. Our second objective was to relate the acoustic properties of these vowels to the perceptual data obtained in our previous work (J. L. Miralles & T. Cervera, 1995). In that study, results indicated that vowels produced by alaryngeal speakers were well perceived in word context. Vowels were produced in CVCV word context by two groups of patients who had undergone laryngectomy: tracheoesophageal speakers (TES) and esophageal speakers. In addition a control group of normal talkers was included. Audio recordings of 24 Spanish words produced by each speaker were analyzed using CSL (Kay Elemetrics). Results showed that F1, F2, and vowel duration of alaryngeal speakers differ significantly from normal values. In general, laryngectomized patients produce vowels with higher formant frequencies and longer durations than the group of laryngeal subjects. Thus, the data indicate modifications either in the frequency or temporal domain, following the same tendency found in previous studies with English-speaking laryngectomized speakers.

Rate-responsive pacing: clinical experience.

Single chamber, rate-responsive pacing is emerging as a new modality in cardiac pacing and in the near future, dual chamber rate-responsive pacing may be the optimal solution for most pacemaker patients. In this report we describe our short- and long-term clinical experience with two different rate-responsive pacemakers: the RS4, an asynchronous atrial sensing ventricular pacemaker, and the TX-pacemaker, which senses the evoked QT after a ventricular paced beat, as an indicator of metabolic demand. Both systems use a single ventricular lead. Nine patients received RS4 and 10 patients received TX units. All of these patients had AV block and good ventricular function except for three patients with sinus node disease in the TX group. Between 1 and 3 months after implantation, a 24-hour Holter monitoring was performed, during which two maximal symptom-limited treadmill exercise tests (Bruce protocol) were conducted in VVI (70 bpm) and rate-responsive modes, in a random fashion. The mean follow-up was 25 months in RS4 group and 10 months in TX group. Significant improvements in patient exercise tolerance were found in the rate-responsive mode (9.0 vs. 6.6 METs in VVI) with similar results in both groups (RS4 and TX) despite higher ventricular pacing rates in the TX group (121 bpm vs. 102 bpm in RS4). An autolimited rate-responsive pacemaker-mediated tachycardia, induced by retrograde ventriculo-atrial conduction, was observed in a patient with an RS4.(ABSTRACT TRUNCATED AT 250 WORDS)