Réduction du bruit ambiant dans les sons acoustiques respiratoires

RÉSUMÉ : Le bruit ambiant présent dans les sons respiratoires cause beaucoup de problèmes aux médecins lors de l'auscultation des patients atteints de maladies respiratoires. Il est difficile dans ces conditions de bruit ambiant de faire un diagnostic efficace et juste des maladies respiratoires chez les patients auscultés. Les médecins ayant moins d'expériences dans l'écoute des sons respiratoires pourront difficilement détecter une maladie respiratoire dans les conditions ambiantes bruyantes perturbant l'écoute du son respiratoire. L'objectif de notre recherche est de trouver un algorithme robuste et efficace qui réduit le bruit ambiant dans les sons acoustiques respiratoires des patients hospitalisés. Les algorithmes sélectionnés doivent réduire le bruit ambiant au maximum tout en préservant la qualité du son acoustique respiratoire du patient. En se basant sur les ressemblances acoustiques entre les sons respiratoires et les sons de paroles, les méthodes utilisées dans le domaine du rehaussement de la parole à savoir : le filtrage adaptatif (AF), la soustraction spectrale (SS) et la séparation aveugle de source (BSS) ont été utilisées dans nos travaux. Des données de test obtenues par un mélange additif, un mélange convolutif et des enregistrements réels ont été utilisées pour l'évaluation des performances de ces techniques. L'évaluation des différents algorithmes est réalisée par des méthodes subjectives caractérisées par un test d'écoute utilisant le score d'opinion moyen (MOS) et objectives basées sur le rapport signal-sur-bruit (SNR) avant et après filtrage, la corrélation croisée (CC), l'erreur quadratique moyenne normalisée (NMSE) et le rapport signal-sur-interférence (SIR). Les résultats des évaluations ont révélé une préférence des participants, pour ce qui est du test d'écoute, à l'utilisation de la méthode du filtrage adaptatif (AF) pour la réduction du bruit de type additif dans les sons acoustiques respiratoires. Pour le type de mélange convolutif et des enregistrements réels, le choix des participants s'est porté sur l'utilisation de la méthode de la séparation aveugle de sources (BSS). -- Mot(s) clé(s) en français : Sons acoustiques respiratoires, bruit ambiant, réduction du bruit, filtrage adaptatif, soustraction spectrale, séparation aveugle des sources. -- ABSTRACT : Ambient noise in respiratory sounds causes many problems for physicians when ausculting patients with respiratory diseases. It is difficult under these ambient noise conditions to make an effective and accurate diagnosis of respiratory diseases in hospital patients. Physicians with less experience in listening to respiratory sounds will have difficulty detecting respiratory disease in the noisy ambient conditions that interfere with listening to respiratory sounds. Our research goal is to find a robust and efficient algorithm that reduces the ambient noise in the respiratory acoustic sounds of hospitalized patients. The selected algorithms should reduce the ambient noise as much as possible while preserving the quality of the patient's breath sounds. Based on the acoustic similarities between breath sounds and speech sounds, the methods used in the field of speech enhancement known as: adaptive filtering (AF), spectral subtraction (SS), and blind source separation (BSS) were used in our project. Testing data obtained from additive mixing, convolutional mixing and real recordings were used to evaluate the performance of these techniques. The evaluation of the different algorithms is carried out by subjective methods characterized by a listening test using the mean opinion score (MOS) and objective methods based on the signal-to-noise ratio (SNR) before and after filtering, the cross-correlation (CC), the normalised mean square error (NMSE), and the signal-to-interference ratio (SIR). The evaluation results revealed a preference of the participants, in terms of the listening test, to use the adaptive filter (AF) method for the reduction of additive type noise in breath sounds. For the convolutional mixing type and real recordings, the participants' choice was to use the blind source separation method (BSS). -- Mot(s) clé(s) en anglais : Respiratory acoustic sounds, ambient noise, denoising, adaptive filtering, spectral subtraction, blind source separation

ÉLABORATION ET CARACTÉRISATION MÉCANIQUE ET PHYSIQUE DES PANNEAUX DE PARTICULES DE SCIURE DE KAPOKIER AVEC LA POUDRE TANIFÈRE DE LA COSSE DE GOUSSE DE NÉRÉ

The goal of this work is to develop carpentry residues which are the kapok tree with tannic powders pod locust bean (Parkiabiglobosa), for the manufacture of particle board to seek palliative environmental problems of sawdust and the use of conventional binders. The work consisted firstly, to make particleboard with the sawdust of kapok tree by varying the percentage of tannic powder pod locust bean and secondly, to determine the physical and mechanical properties of particleboard panels made by means of three-point bending test, the tensile test, testing of internal bound, the water absorption and thickness swelling test. The bending test used to calculate the modulus of elasticity (MOE) which is between 7 840 MPa and 19 500 MPa modulus of rupture (MOR) varying between 6.84 MPa and 12.14 MPa. That of traction leads to the determination of Young's modulus (Re) in the range of 6 660 MPa to 19 869 MPa, also the modulus of rupture (MOT) varying between 19.16 MPa and 28.36 MPa, the internal bound (IB) between 0.294 MPa and 1.357 MPa. The threshold set by the ANSI A.1-1999 for MOE, MOR and IB standard, has been largely achieved. The values of density used to classify the particleboard panels of sawdust kapok tree in the categories of medium and high density. This shows that tannic powders of pod locust bean can validly replace conventional binders in the manufacture of particleboard

Testing of Beeswax Printing Technology in the Design of a Paper-Based Microfluidic System

The development of additive manufacturing technologies has the advantage of producing more economical and efficient products. This trend is supported by the fact that this technology is extensively developed, so that it has easy platforms to use, vast applications, and is more economically affordable than it was when it was first created in the early 90s. Currently, this technology is also widely applied in the bioengineering field to produce so called micro-scale products. In this study, a beeswax printer was developed by modifying a universal 3D printer to apply beeswax as a microchannel part on paper. Ultimately, this application shall be used for paper lab-on-a-chip (LOC) that enables us to perform specific functions, such as biological detection. However, a thorough study is needed to understand the limitations of this beeswax printer, along with the characterization of its product. Here, an experiment was conducted to find the optimum conditions of the system with two main parameters, namely the heating characteristics and flowability of the molten beeswax during the printing process. Additionally, an analytical model was also developed to validate the phenomena of this advanced printing media. Briefly, the beeswax printer allowed us to have a fine profile in the range of 0.5–2.0 mm wide and 30–150 µm thick. This research allowed us to find the desired profile of printed beeswax

What is the secondary patency of thrombosed bypasses of the lower limbs cleared by fibrinolysis in situ?

OBJECTIVES: In case of acute thrombosis, lower limbs bypasses can, in certain cases, be cleared by local intra-arterial fibrinolysis (LIF). The aim of this study was to evaluate the secondary patency of thrombosed bypasses after fibrinolysis. METHODS: This retrospective study includes all patients hospitalized for thrombosed bypasses of the lower limbs that were treated with in situ fibrinolysis using urokinase, between 2004 and 2013, in two French university hospital centers. Fibrinolysis was indicated in case of recent thrombosis (< 3 weeks) provoking acute limb ischemia without sensory-motor deficit and in the absence of general contraindications. The secondary patency of the grafts was defined as the time after fibrinolysis without a new thrombotic event. RESULTS: There were 207 patients, hospitalized for recent thrombosis of 244 bypasses. The LIF was efficient in 74% of the cases (n=180). Secondary patency of these bypasses, was 54.2% and 32.4% overall, 68.3% and 50.3% for the supra-inguinal bypasses and 48.3% and 21.5% for the infra-inguinal bypasses, at 1 year and 5 years respectively. There is a significant difference (p = 0.002) regarding the permeability of the supra-inguinal and infra-inguinal bypasses. The survival rate was 75% (± 6.4%) at 5 years and the limb salvage rate was 89% (± 3.3%), 78.2% (±5.1%) and 75% (±5.8%) at 1 year, 3 years et 5 years respectively. The only independent factor influencing the secondary patency of infra-inguinal bypasses that was significant in a multivariate analysis was the infragenicular localization of the distal anastomosis (p=0.023). CONCLUSIONS: LIF is an effective approach that often allows the identification of the underlying cause, permitting elective adjunctive treatment of the underlying cause. Although LIF is at least as effective as its therapeutic alternatives described in the literature, the secondary patency of the bypasses remains modest and encourages close monitoring, particularly in patients with an infragenicular bypass

Whole-genome sequencing of a Plasmodium vivax clinical isolate exhibits geographical characteristics and high genetic variation in China-Myanmar border area

Maximum-Likelihood phylogenetic tree of P. vivax constructed from the 108,846 SNPs occurring in at least half of the samples. Lineages are colored according to geographic origin. Branch lengths indicate considerable diversity in P. vivax strain. Numbers at nodes indicate percentages of bootstrap support. (TIF 254 kb

ÉLABORATION ET CARACTÉRISATION MÉCANIQUE ET PHYSIQUE DES PANNEAUX DE PARTICULES DE SCIURE DE KAPOKIER AVEC LA POUDRE TANIFÈRE DE LA COSSE DE GOUSSE DE NÉRÉ

The goal of this work is to develop carpentry residues which are the kapok tree with tannic powders pod locust bean (Parkiabiglobosa), for the manufacture of particle board to seek palliative environmental problems of sawdust and the use of conventional binders. The work consisted firstly, to make particleboard with the sawdust of kapok tree by varying the percentage of tannic powder pod locust bean and secondly, to determine the physical and mechanical properties of particleboard panels made by means of three-point bending test, the tensile test, testing of internal bound, the water absorption and thickness swelling test. The bending test used to calculate the modulus of elasticity (MOE) which is between 7 840 MPa and 19 500 MPa modulus of rupture (MOR) varying between 6.84 MPa and 12.14 MPa. That of traction leads to the determination of Young's modulus (Re) in the range of 6 660 MPa to 19 869 MPa, also the modulus of rupture (MOT) varying between 19.16 MPa and 28.36 MPa, the internal bound (IB) between 0.294 MPa and 1.357 MPa. The threshold set by the ANSI A.1-1999 for MOE, MOR and IB standard, has been largely achieved. The values of density used to classify the particleboard panels of sawdust kapok tree in the categories of medium and high density. This shows that tannic powders of pod locust bean can validly replace conventional binders in the manufacture of particleboard

Determining the most significant changes on intergenerational communication and young people’s family planning and reproductive health outcomes: Qualitative evaluation of the Merci Mon Héros media campaign in Niger and Côte d’Ivoire

Merci Mon Héros (MMH) is a mixed media campaign that catalyzes young people as co-leaders to improve intergenerational communication and young people’s family planning (FP) and reproductive health (RH) outcomes. Breakthrough ACTION co-facilitated and codeveloped this youth-led campaign in francophone African countries while the Breakthrough RESEARCH project was tasked with evaluating the MMH campaign to determine the most significant changes in the communities exposed to the mixed media campaign in Niger and Côte d’Ivoire. Using the qualitative methodology of Most Significant Change, participants shared personal narratives during focus group discussions in each country. The diverse stories collected in both countries demonstrate how the MMH campaign can create an enabling environment for young people and adults to begin communicating about FP/RH and access the information, support, and services they need. While there is still a long way to go to eradicate taboos around FP/RH for adolescents and dispel myths that access to information promotes promiscuity, this evaluation found that some youth and adults exposed to the MMH campaign are contributing to a more enabling environment for others around them to talk about and access FP/RH information and quality services