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Contactless techniques are of increasing clinical interest as they can provide advantages in terms of comfort and safety of the patient with respect to sensor-based methods. Therefore, they are particularly well suited for vulnerable patients such as newborns. Specifically the acoustical analysis of the infant cry is a contactless approach to assist the clinical specialist in the detection of abnormalities in infants with possible neurological disorders. Along with the perceptual analysis, the automated analysis of infant cry is usually performed through software tools that however might not be devoted to this specific signal. The newborn cry is a signal extremely difficult to analyze with standard techniques due to its quasi-stationarity and to very high range of frequencies of interest. Therefore software tools should be specifically set and used with caution. To address this issue three methods are tested and compared, one freely available and other two specifically built using different approaches: autoregressive adaptive models and wavelets. The three methods are compared using synthetic signals coming from a synthesizer developed for the generation of basic melodic shapes of the newborn cry. Results point out strengths and weaknesses of each method, thus suggesting their most appropriate use according to the goals of the analysis. [ABSTRACT FROM AUTHOR]

The recovering of trivalent Lanthanides from aqueous solutions, by biosorption process onto Galdieria sulphuraria lifeless cells, was investigated. Potentiometry, UV–Vis, FTIR-ATR spectroscopy and SEM-EDS analysis were used. All the experiments were performed at 25 °C, in 0.5 M NaCl. Ln3+ biosorption is greater in the 5–6 pH range with values ranging from 80 μmol/g to 130 μmol/g (dry weight). The adsorbed Ln3+ ions can be recovered at higher acidity (pH<1) and the biosorbent can be reused. Specific molecular interactions between Ln3+ ions and the functional groups on G. sulphuraria surface were highlighted. Particularly, proteins are involved if Ln3+=Pr3+, Sm3+, Eu3+, Tb3+, Dy3+, Tm3+, while Ce3+, Ho3+, Er3+ form bonds with carbohydrates. Finally, both proteins and carbohydrates are involved if Gd3+ and Yb3+. A Surface Complexation approach, with a good graphical fitting to potentiometric experimental collected data, was used to describe the biosorption mechanism. This study could be of great applicative utility for removing of trivalent actinides, from waste aqueous solutions, by biosorption. As well known the lanthanides were used as model to simulate the chemical behaviour of actinides in the same oxidation state. [Display omitted] • Lanthanides biosorption onto G. sulphuraria greater at pH > 4. • Specific interactions Lanthanides-functional groups onto G. sulphuraria surface. • Lanthanides biosorption mechanism onto G. sulphuraria explained by a Surface Complexation Model. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) involves impairments of voice and speech (hypokinetic dysarthria). Dysprosody is one of the most common features of PD speech that includes alterations of rhythm and velocity of articulation. The aim of this study is the evaluation of dysprosody patterns in Parkinsonian patients during a sentence repetition task by means of a fully automated tool. Twenty PD patients (14 male and 6 female) and 19 healthy controls (9 male and 10 female) were tested. Results show significant differences between the two groups as far as the time interval between each sentence repetition ( T inter ), the percent of speech time with respect to sentence duration ( D %) and the Net Speech Rate (NSR – defined as the number of syllables of the sentence divided by the effective speech time) are concerned. In particular, T inter is larger in PD patients while D % is higher in the control group. These results show that PD patients may exhibit longer pauses between each sentence repetition and a lower percentage of “speech time” during a whole repetition period. Thus, the decrease of D % leads to an increase of NSR. Other acoustic parameters (noise and F0 variability) did not show any significant difference. This study confirms that speech in PD patients is characterized by short rushes followed by unorthodox pauses. These results may lead to the development of a system for the automatic acoustic analysis which could significantly reduce the processing time in particular during pre-processing, that to date is a time-consuming and operator-dependent step especially in case of recordings of long duration. [ABSTRACT FROM AUTHOR]

Abstract: Nowadays, great attention is devoted to minimizing the discomfort caused by connection of patients to sensors for long-term monitoring of physiological parameters. Hence, the need for contact-less monitoring systems is increasingly recognized in clinical investigation. To this aim, audio signals recorded by ambient microphones are an appealing and increasing field of research: in the biomedical field, application of contact-less audio recording of long duration may concern obstructive apnoea syndrome, preterm newborns in Intensive Care Units, daily monitoring in occupational dysphonia, speech therapy, Parkinson and Alzheimer disease, monitoring of psychiatric and autistic subjects, etc. However, a significant amount of ambient noise is inevitably included in the records. Especially in the case of recordings that take a long time, manual extraction of clinically useful information from a whole record is a time-consuming operator-dependent task, the length of a whole recording (even several hours) being prohibitive both for perceptual analysis made by listening to it and for visual inspection of signal patterns. Moreover, objective measures of signal characteristics may serve clinicians as a common ground for diagnosis. Hence, automatic methods are needed to speed up and objectify the analysis task. The present work describes a new, automatic, fast and reliable method for extracting “voiced candidates” from audio recordings of long duration for both clinical and home applications. To demonstrate its effectiveness, the method is compared to existing software tools commonly used in biomedical applications using synthetic signals. [Copyright &y& Elsevier]

Abstract: In this paper we present results concerning validity of jitter measurement in strongly irregular voice signals (sustained vowels) moderately corrupted by noise. The performance of four tools for voice analysis is compared on synthetic signals as far as fundamental period and jitter estimation are concerned. Synthesised vowels offer the advantage of a perfect control of the amount of jitter put in. Though implementing the same formula for jitter estimation, the results obtained with these approaches become quite different for increasing jitter. The reason could be searched in the different methods used for the separation of voiced and unvoiced frames as well as for fundamental period estimation. Results show that all the tools give reliable results up to a jitter level J =15%, that encompasses the maximum value J =12% as obtained by expert raters by visual inspection. Hence, up to this limit, the tools presented here for jitter estimation can give a valid support to clinicians also in term of reproducibility of results and time saving. For jitter values larger than 15% all programs tend to underestimate the true jitter value, but with large differences among them. Just two methods succeed in estimating jitter values up to and larger than 20% and could thus be better suited for perturbation measure in strongly irregular voice signals. [Copyright &y& Elsevier]

Abstract: Infant cry characteristics reflect the development and possibly the integrity of the central nervous system. This study evaluates the distress occurring during cry in preterm newborn infants, as related to decrease of central blood oxygenation. A recording system was developed, that allows synchronised, non-invasive monitoring of blood oxygenation and audio recordings of newborn infant''s cry. Cry episodes were identified by an automatic system allowing further analysis of the changes induced by the cry episodes on the oxygen saturation level in the central nervous system. Specifically, decrease in the oxygenation level appears during a cry episode, followed by recovery of the oxygenation after the cry episode is over. In the present work we compare a group of preterm infants with a control group of full term newborns in order to detect possible differences between the two sets of patients. Results indicate that a similar decrease in oxygenation level occurs in both groups of patients, but the recovery time after the crying episode is more stable and rapid in full term newborns than in preterm ones. This could prove useful for clinicians and nurses in the prevention of developmental diseases for this class of patients. [Copyright &y& Elsevier]

Abstract: Objective measurement of the severity of dysphonia typically requires signal processing algorithms applied to acoustic recordings. Since Lieberman (1963) introduced the concept of perturbation analysis in the area of voice, the best-known acoustic parameter in clinical practice is conventional jitter. However, jitter measurements have some critical limitations. According to a widely accepted guideline, in sustained vowels of dysphonic voices, only perturbation measures less than about 5% are reliable: this is related to period extraction methods. This limit of 5% deserves critical analysis, certainly when there are indications that some acoustic analysis programs can be applied to quite irregular voices such as substitution voices. The present experiment demonstrates that – on signals of synthesized deviant voices (sustained vowel) with moderate additive noise – different raters are able to visually identify in a very consistent way the period durations of successive cycles up to values of about 13% jitter. Furthermore, even for higher values – over 30% – the jitter % computed with the period values rated by visual perception is, for some of the raters, very comparable to the real value. This suggests that improved acoustic programs using more reliable algorithms could validly transgress the traditional limit of 5% if they demonstrate the correspondence of their computations with the true jitter values. This is now made possible by synthesizers generating artificial deviant voices that cannot be distinguished from true dysphonia, and in which the jitter put in is exactly known. [Copyright &y& Elsevier]

Abstract: Voice is the result of the coordination of the whole pneumophonoarticulatory apparatus. The analysis of the voice allows the identification of the diseases of the vocal apparatus and currently is carried out from an expert doctor through methods based on the auditory analysis. The paper presents a web-based system for the acquisition and automatic analysis of vocal signals. Vocal signals are submitted by the users through a simple web-interface and are analyzed in real-time by using state-of-the art signal processing techniques, providing first-level information on possible voice alterations. The system offers different analysis functions to the doctors that may analyze suspected cases in detail. The system is currently being tested in the otorhinolaryngologist setting to carry out mass prevention via screening at a regional scale. [Copyright &y& Elsevier]

Abstract: Infant monitoring is a common procedure in clinical practice in neonatal critical care units. A number of vital functions are monitored, such as heart beat, breathing, blood flow, etc. Specifically, preterm and/or low-birth-weight infants often present respiratory problems that require monitoring. These may range from insufficient ventilation to apnoea. One of the most common events that may affect the respiratory flow is crying, a physiological action made by the infant to communicate and draw attention, but, for a preterm infant, this action requires great effort, which may cause distress and even may have an adverse impact on blood oxygenation. Acoustic analysis of newborn infant cry is thus of importance, since it is related to other basic neuro-physiological parameters. Being easy to perform, cheap and completely non-invasive, it can be successfully applied in many circumstances. The newborn infant cry is characterised by very high fundamental frequency (F 0) and resonance frequency (RFs) values, with abrupt changes and voiced/unvoiced features of very short duration in a single utterance. To deal with such signals, a new user-friendly software tool has been developed, that allows robust tracking of main acoustic parameters on very short and time-varying signal frames. The software developed provides the user with a high-resolution picture of the cry signal characteristics. [Copyright &y& Elsevier]

Abstract: Vocal folds oscillation crucially influences all the basic qualities of voice, such as pitch and loudness, as well as the spectrum. Stroboscopy provides the standard view of the larynx. However, a two-dimensional high-speed imaging system currently cannot provide enough image resolution to evaluate irregular vocal fold vibrations, due to the limitation of transmission speed and storage volume. Videokymography is a new diagnostic tool developed to overcome specific limitations of stroboscopy in severely dysphonic patients with an aperiodic signal. It registers the movements of the vocal folds with a high time resolution on a line perpendicular to the glottis. The technique, being independent from the periodicity and intensity of the vocal signal, allows an objective evaluation of vocal folds function. However, due to its novelty, no established clinical evaluation protocol, or validity and reliability data are available for videokymography. Moreover, few results concerning objective parameter estimation from videokymographic images are available. The main focus of this paper is on measuring and tracking quantitative parameters for objective vocal fold functional assessment, from videokymographic (VKG) examinations of subjects with normal and pathological laryngeal function, based on active contour search implemented with a properly adjusted robust snake algorithm. The method is designed to deliver to the clinician the essential objective information of VKG in an effective way, as an aid to its subjective and intuitive skilfulness. A set of VKG images has been analysed, coming both from healthy and dysphonic subjects, recorded at the Otolaryngology Department, University of Milan, Italy, showing the robustness and reliability of the proposed technique. [Copyright &y& Elsevier]

Until a few years ago there had been no record of stress corrosion cracking (SCC) as a main cause of failures in Argentine pipelines, but as the pipeline system became of a certain age this mechanism started to have an important impact on reliability. This study analyzes three blowouts attributed to high pH SCC in different oil and natural gas transmission pipelines, which occurred by the sudden propagation of longitudinal cracks at the outer surface of the pipes. [Copyright &y& Elsevier]

A noise reduction scheme, particularly suited for the correction of vocal pathologies, is proposed. The filter makes use of concepts originated within the theory of dynamical systems and deterministic chaos. In particular, the idea of embedding scalar data in order to reconstruct a phase space is of fundamental importance here. Furthermore, the concept of an attractor as a result of dynamical constraints is exploited. In order to perform noise reduction one needs redundancy and the human voice provides it even within a phoneme, namely the smallest structural unit of speech. Due to several repetitions of a pattern called pitch inside a phoneme, separation between the pure voice signal and the noise is possible, provided the latter is uncorrelated with the former. With a proper parameter tuning, different kinds of noise can be removed. We describe the idea behind the noise reduction algorithm and present applications to vocal pathologies. [Copyright &y& Elsevier]

Herein, non-linear prediction methods are applied to oesophageal voice analysis. The research aims to investigate normal and pathological subjects, in order to improve knowledge of the oesophageal voice behaviour. Analysis is performed in the reconstructed phase space, using both non-linear prediction with local linear approximation and the S-Map method. Preliminary results seem to confirm that in normal subjects a non-linear stable deterministic behaviour takes place, while in pathological subjects the non-linear contribution reduces while the time series becomes unstable. [Copyright &y& Elsevier]

• First results are presented concerning the automated mother language assessment of healthy full term newborns. • About 7.500 cry units coming from French, Arabic and Italian mother-tongue newborns are analyzed. • Acoustical parameters and 12 different melodic shapes are computed with the BioVoice software tool. • Classification is performed with Random Forest and 4 neuro-fuzzy classifiers. • Results show up to 95% differences among the three languages. Recent research studies have shown that since the last trimester of pregnancy human fetuses are able to listen to and possibly memorize auditory stimuli from the external world, both as music and language are concerned. In particular, they exhibit a specific sensitivity to prosodic features such as melody, intensity, and rhythm that are essential for an infant to learn and develop the native language. This paper presents first results concerning the automated mother language identification of a set of about 7500 cry units coming from French, Arabic and Italian mother-tongue healthy full term newborns. Acoustical parameters and 12 different melodic shapes are computed with the BioVoice software tool and their classification is performed with Random Forest and 4 neuro-fuzzy classifiers. Results show up to 95% differences among the three languages. [ABSTRACT FROM AUTHOR]

Summary Smartphone technology provides new opportunities for recording standardized voice samples of patients and sending the files by e-mail to the voice laboratory. This drastically improves the collection of baseline data, as used in research on efficiency of voice treatments. However, the basic requirement is the suitability of smartphones for recording and digitizing pathologic voices (mainly characterized by period perturbations and noise) without significant distortion. In this experiment, two smartphones (a very inexpensive one and a high-level one) were tested and compared with direct microphone recordings in a soundproof room. The voice stimuli consisted in synthesized deviant voice samples (median of fundamental frequency: 120 and 200 Hz) with three levels of jitter and three levels of added noise. All voice samples were analyzed using PRAAT software. The results show high correlations between jitter, shimmer, and noise-to-harmonics ratio measured on the recordings via both smartphones, the microphone, and measured directly on the sound files from the synthesizer. Smartphones thus appear adequate for reliable recording and digitizing of pathologic voices. [ABSTRACT FROM AUTHOR]

The measure of acoustic parameters related to dysphonia has long been one of the main research challenges in voice analysis. When the origin of the voice disorder is occupational, the medico-legal and insurance aspects must be considered, involving, when relevant, the definition of a percentage of physical impairment (usually 1-10% according to the guidelines). An objective aid capable of quantifying these levels is desirable for assisting the medico-legal expert. Vocal fold nodules in voice professionals are mentioned in the European List of Occupational Diseases. Generally, such voices are slightly to moderately deviant, and mainly characterized by audible air escape (breathiness), due to insufficient vocal fold closure. Mild amounts of jitter may also be present. No studies have been published so far testing the ability of software tools to discriminate levels of added noise in signals when the amount of noise is exactly known. In the present study, four program tools (BioVoice, PRAAT, MDVP and AMPEX) are tested on realistic synthesized voice signals corrupted by 4 slightly increasing levels of jitter and 10 levels of additive noise close to the degree of dysphonia occurring in real patients with vocal fold nodules. The results show that the four tools are able to correctly estimate both jitter and noise levels. Specifically for noise, in some cases the agreement is close to 100%. Thus they could be of help to clinicians in determining the level of impairment to quantify compensation in patients affected by an occupational voice disorder. [ABSTRACT FROM AUTHOR]

This paper deals with the analysis of cry melodies (time variations of the fundamental frequency) as well as vocal tract resonance frequencies (formants) from infant cry signals. The increase of complexity of cry melodies is a good indicator for neuro-muscular maturation as well as for the evaluation of pre-speech development. The variation of formant frequencies allows an estimation of articulatory activity during pre-speech vocalization. Subjects are three pairs of healthy identical twins (monocygozity determined by DNA-fingerprint). Spontaneous cries of these six children were recorded at different ages: 8th–9th week, 15th–17th week and 23rd–24th week. Analysis of 136 cry melodies and intensity contours was made using KAY-CSL 4300/MDVP. For formant estimation a spectral parametric technique was applied, which was based on autoregressive models (Digital spectral analysis with applications, 1987) whose order is adaptively estimated on subsequent signal frames by means of a new method (Med. Eng. Phys. 20 (1998) 432; Utras. Med. Biol. 21 (1995) 793). Cry melodies exhibited an increasing complexity during the observation period. Beginning with the second observation period (15th–17th week) an increasing coupling and tuning between melody and resonance frequencies was observed, which was interpreted as “intentional” articulatory activity. Possible applications are in cry diagnosis as well as in the evaluation of pre-speech development. [Copyright &y& Elsevier]

This paper discusses the failure of a vintage 10 kg LPG balloon or carafe, manufactured in 1968, and the following experimental study of material properties and fabrication procedures of other vessels of similar age. It is concluded that many of the carafes present fabrication and in-service defects, especially in the circumferential welds, that can become critical. Continuing use of these vessels is potentially dangerous, especially when the effectiveness of the post weld stress relief treatment can not be guaranteed. [Copyright &y& Elsevier]