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ABSTRACT In the realm of architecture ground-penetrating radar has been used as nondestructive technique to assess physical properties of wood structures in situ. However, a better understanding of the dielectric [...]

AbstractThis paper presents new advances in speech technology carried out by the Speech Technology Group (GTH) at the Universidad Politecnica de Madrid (iJPM) to develop enhanced interfaces at home. These interfaces provide a better interaction for people with disabilities. The speech recognizer includes a speaker identification feature (that makes an acoustic adaptation possible for improving recognition performance) and an emotion classifier (to detect the user emotion). The understanding module, with a bottom-up strategy, increases its flexibility against recognition errors. The dialog manager has been improved by a new dialog control based on Bayesian Networks and a new platform for developing multimodal, multilingual, and user dependent dialog services from scratch. Finally, the speech synthesis module includes new advances for increasing the voice naturalness and incorporating emotions. These advances have been integrated into a new interface for controlling a Hi-Fi audio system, thus significantly increasing its ergonomics.

AbstractNeural networks (NNs) have been extensively used in speech technology systems. In this paper, we present two novel applications of NNs in speech recognition and text-to-speech systems. The prosodic modeling is one of the most important tasks for developing a new text-tospeech synthesizer, especially in a female-voice high-quality restricted-domain system. Our double objective is to get accurate predictors for both the fundamental frequency (FO) curve and phoneme duration by minimizing the model estimation error in a Spanish text-to-speech system, by means of a neural network estimator, which has proved to be an excellent tool for the modeling. The resulting system predicts prosody with very good results (for duration: 15.5 ms in RMS and a correlation factor of 0.8975; for F0: 19.80 Hz in RMS and a relative RMS error of 0.43) that clearly improves our previous rule-based system.

There is now an increasing body of evidence to support the practice of allergen-specific sublingual-swallow immunotherapy (SLIT) in the treatment of IgE-mediated respiratory allergies. Recent studies on traditional injection therapy have pointed out that this form of treatment is not only capable to decrease actual allergic symptoms, but may also have long-term clinical and preventive effects and may influence atopy natural history. In the year 2000, our group published a retrospective, multicenter study showing the efficacy and safety of SLIT in a survey of 302 patients. We now carried out a second study on the same patients, with the aim of investigating long-term and preventive effects of SLIT. Beside the well-known safety and efficacy of this treatment (80.8 % of patients reported clinical benefits), SLIT proved also to elicit long term clinical effects: over a mean follow-up of 11.6 months after the end of treatment, 80.8 % of patients still mantained the previously achieved benefits. During the follow-up period, only 1 % of non-asthma patients reported an onset of respiratory symptoms, and only 9.6 % of patients undergoing new skin tests showed new sensitizations. All the clinical benefits were strongly linked to the length of treatment: patients with long-lasting benefits were treated for a mean length of 29.1 months, while patients showing a return to pre-SLIT condition were treated for a mean 13.3 months. SLIT can obtain long-term and preventive effects so far attributed to injection immunotherapy.

The usual model of intermittent hypoxia (sleep apnoea) corresponds to repeated episodes of hypoxia from a few seconds to a few hours interspersed with episodes of normoxia. The aim of this study was to evaluate in rats the effect of two periods of intermittent exposure for 2 months to hypoxia (IHX1, 24 h in hypoxia (428 Torr), 24 h in normoxia; IHX2, 48 h in hypoxia (428 Torr), 24 h in normoxia) as a new model of hypoxia simulating intermittent exposure to high altitude experienced by Andean miners. We assessed the haematological parameters, time course of resting heart rate and systolic blood pressure. We also evaluated the expression of adrenergic and muscarinic receptors. IHX1 and IHX2 produced an increase in haematocrit, haemoglobin concentration and mean corpuscular volume as previously seen in most hypoxic models. IHX1 and IHX2 induced a similar sustained elevation of systolic blood pressure (132 ± 2 and 135 ± 3 mmHg, respectively, vs.the control level of 121 ± 16 mmHg) after 10 days of exposure without change in heart rate. Right ventricular (RV) hypertrophy (225 ± 13 and 268 ± 15 mg g−1, vs.178 ± 7 mg g−1) and downregulation of α1‐adrenoceptor (RV: 127 ± 21 and 94 ± 16 fmol mg−1vs.157 ± 8 fmol mg−1; left ventricle (LV): 141 ± 5 and 126 ± 9 fmol mg−1vs.152 ± 5 fmol mg−1) have been found in both groups, with right ventricular hypertrophy being greater and α1‐adrenoceptor density being lower in IHX2 than in HX1 groups. These data indicate that both parameters are related to the time of exposure to hypoxia. IHX1 and IHX2 produced the same magnitude of upregulation of muscarinic receptors (LV, 60%; RV, 40%), and no change in β‐adrenoceptors. In conclusion, exposure to intermittent hypoxia led to polycythaemia and RV hypertrophy as observed in other types of hypoxia. A specific cardiovascular response was seen, that is an increase in blood pressure without change in heart rate, which was different from the one observed in episodic and chronic hypoxia. Furthermore, this model involved specific modifications of α1‐adrenergic and muscarinic expression.

Cell-free extracts of Thermus thermophilus HB8 catalyze the in vitro, NADH-dependent reduction of potassium tellurite (K2TeO3). Three different protein fractions with tellurite-reducing activities were identified. Two exhibited high molecular weight and were composed of at least two different polypeptides. The protein in the third fraction was purified to homogeneity and had a single polypeptide chain of 53 to 54 kilodaltons, with an isoelectric point of 8.1. Each enzyme was thermostable, the temperature optimum was 75 degrees C, and 30 mM NaCl, 1.5 M urea, or 0.004% sodium dodecyl sulfate caused 50% inhibition of the enzymes. However, 2% Triton X-100 did not have an inhibitory effect. The enzymes were also able to catalyze the reduction of sodium selenite and sodium sulfite in vitro. NADH was replaceable by NADPH. Divalent cations, such as Ca2+ and Ba2+, had no effect on the activity, while similar concentrations of Zn2+, Ni2+, and Cu2+ abolished the activity. This reductase activity could enable these bacteria both to reduce K2TeO3 and to increase their tolerance toward this salt.

Polyphenolic composition (flavonoids and phenolic acids and aldehydes) is studied in the Et2O soluble fractions of the methanolic extracts ofEucalyptus camaldulensis, E. globulusandE. rudisbark. Gallic, protocatechuic, vanillic and ellagic acids, and protocatechuic aldehyde were identified in the three species; eriodictyol, quercetin and naringenin, inE. camaldulensisandE. globulus; vanillin, inE. camaldulensisandE. rudis; naringin, quercitrin, luteolin and kaempferol, inE. camaldulensis; taxifolin and apigenin, inE. globulus; and methyl benzoates and cinnamates, inE. rudis. Some unidentified ellagitannins, flavonols and flavanones were also detected. Significant differences in composition among species were found:E. rudisshowed the lowest concentration in flavonoids andE. globuluspresented higher concentration and variety of ellagitannins than the others.