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Gas hydrates can be formed when light gases, such as the components of natural gas, come into contact with water under particular conditions of temperature and pressure. These solid compounds give rise to problems in natural gas and oil industry because they can plug pipelines and process equipment. To prevent hydrate formation methanol and glycols are commonly and extensively used as inhibitors. Today, the thermodynamic equilibria of hydrate formation are well known, but the kinetics of gas hydrate formation and growth has to be studied in order to find means of controlling these processes and to explore the mechanisms for hydrate formation that follows non equilibrium laws. The present work deals with the kinetics of methane hydrate formation studied in a laboratory loop where the liquid blend saturated with methane is circulated up to a pressure of 75 bar. Pressure is maintained at a constant value during experimental runs by means of methane gas make-up. First the effects of pressure (35-75 bar), liquid velocity (0. 5-3 m/s), liquid cooling temperature ramp (2-15°C/h), and liquid hydrocarbon amount (0-96%), on hydrate formation kinetics are investigated. Then a new method is proposed to predict firstly the thermodynamic conditions (pressure and temperature) at the maximum values of the growth rate of methane hydrate and secondly the methane hydrate growth rate. A good agreement is found between calculated and experimental data. Finally the evaluation of the efficiency of some kinetic additives and some surfactants developed to avoid either nucleation or crystal growth and agglomeration of methane hydrates is tested based on the proposed experimental procedure. Les hydrates de gaz des composés légers du gaz naturel se forment lorsque ceux-ci entrent en contact avec l'eau dans certaines conditions de température et de pression. Ces composés solides sont nuisibles pour les industries gazière et pétrolière car des bouchons solides peuvent obstruer les lignes de transport et les installations de traitement d'effluents pétroliers. Pour contrôler ces dépôts d'hydrates, on utilise fréquemment, comme inhibiteurs, le méthanol ou les glycols. Aujourd'hui, les équilibres thermodynamiques des hydrates de gaz sont bien connus ; par contre, les cinétiques de formation et de croissance doivent être étudiées afin de mettre en évidence de nouveaux moyens de contrôle grâce à l'étude des mécanismes de formation des hydrates hors équilibre. Le présent travail propose une étude de la cinétique de formation de l'hydrate de méthane dans une boucle de recirculation de laboratoire dans laquelle le mélange liquide, saturé de méthane, circule à une pression maximum de 75 bar. La pression constante au cours des expériences est maintenue par ajout de gaz frais. Dans un premier temps, nous avons étudié les effets de la pression (35-75 bar), de la vitesse d'écoulement du liquide (0,5-3 m/s), de la rampe de refroidissement (2-15°C/h) et de la quantité d'hydrocarbure présent dans la charge (0-96 %) sur les cinétiques de formation de l'hydrate. Nous proposons ensuite une nouvelle méthode de prédiction, en premier lieu, des conditions thermodynamiques (pression et température) correspondant aux valeurs de vitesse de croissance maximum de l'hydrate, puis de ces vitesses de croissance maximum. Nous avons obtenu un bon accord entre valeurs expérimentales et calculées. Enfin, nous avons évalué, en utilisant la procédure expérimentale décrite précédemment, l'efficacité de quelques inhibiteurs cinétiques et tensioactifs mis au point pour éviter, soit la nucléation, soit la croissance des cristaux et l'agglomératon de particules d'hydrates de méthane.

La volabilité relative ait; =(yilxi)l(Y;lxi) des constituants d'un mélange binaire a été mesurée à partir d'un nouveau dispositif expérimental, on reporte les données d'équilibre liquide-vapeur obtenues à 45'C de plusieurs binaires : toluène-acétoni-trile, benzène-acétonitrile et benzène-n-heptane. En ajustant à l'équation de Wilson les données expérimentales de «i/; de ces constituants ainsi que des volatilités relatives des constituants des mélanges d'hydrocarbures-alcools, obtenues dans un précédent travail, on calcule les paramètres énergétiques. La prédiction des points de bulle de mélanges binaires et ternaires obtenue à partir de ces paramètres est satisfaisante. La méthode expérimentale ainsi proposée convient particulièrement pour la sélection des solvant extractifs utilisés dans la distillation extractive. From a new expérimental method, relative volatilities aiti = (yilxi)l(yilxi) for a binary mixture are obtained; vapor-liquid equilibrium data are presented for several systems, i.e. toluene-acétonitrile, benzene-acétonitrile and benzene-n-heptane at 45°C. The two adjustable energyparameters of thé Wilson équation, are obtained by adopting thé «,/j data for these binary mixtures and for alcohol-hydrocarbon mixtures previously studied. Theresults obtained in predicting bubble-pressure data for binary and ternary mixtures are consistent with experimental data.

Polyarteritis nodosa is a primary systemic necrotizing vasculitis whose evolution follows, in many cases, a chronic remitting-recurrent course with refractoriness to conventional immunosuppressants. We report here the clinical case of a 75-year-old patient with serologies suggestive of past hepatitis B virus infection who presented a flare of polyarteritis nodosa with great secondary functional impairment. She had not responded to several previous immunosuppressants and required high doses of glucocorticoids to control the flare. After the initiation of biological therapy with tocilizumab, the patient experienced a rapid and marked clinical and analytical improvement, going into clinical remission and being able to remarkably lower the corticosteroid dose and stop the rest of the immunosuppressants. There was no evidence of hepatitis B virus reactivation or changes in the titers of any of the parameters related to the aforementioned infection. This clinical case represents the first case reported in the literature about the successful and safe treatment of polyarteritis nodosa with tocilizumab in a patient with serologies suggestive of past hepatitis B virus infection. [ABSTRACT FROM AUTHOR]

Summary: Background: Acral lesions, mainly chilblains, are the most frequently reported cutaneous lesions associated with COVID‐19. In more than 80% of patients tested, nasopharyngeal swabs were negative on reverse transcription polymerase chain reaction (RT‐PCR) for SARS‐CoV‐2 when performed, and serology was generally not performed. Methods: A national survey was launched on 30 March 2020 by the French Society of Dermatology asking physicians to report cases of skin manifestations in patients with suspected or confirmed COVID‐19 by using a standardized questionnaire. We report the results for acral manifestations. Results: We collected 311 cases of acral manifestations [58.5% women, median age 25.7 years (range 18–39)]. The most frequent clinical presentation (65%) was typical chilblains. In total, 93 cases (30%) showed clinical suspicion of COVID‐19, 67 (22%) had only less specific infectious symptoms and 151 (49%) had no clinical signs preceding or during the course of acral lesions. Histology of skin biopsies was consistent with chilblains. Overall, 12 patients showed significant immunological abnormalities. Of the 150 (48%) patients who were tested, 10 patients were positive. Seven of 121 (6%) RT‐PCR‐tested patients were positive for SARS‐CoV‐2, and five of 75 (7%) serology‐tested patients had IgG anti‐SARS‐CoV‐2. Tested/untested patients or those with/without confirmed COVID‐19 did not differ in age, sex, history or acral lesion clinical characteristics. Conclusions: The results of this survey do not rule out that SARS‐CoV‐2 could be directly responsible for some cases of chilblains, but we found no evidence of SARS‐CoV‐2 infection in the large majority of patients with acral lesions during the COVID‐19 lockdown period in France. What is already known about this topic? About 1000 cases of acral lesions, mainly chilblains, were reported during the COVID‐19 outbreak.Chilblains were reported to occur in young people within 2 weeks of infectious signs, which were mild when present.Most cases did not have COVID‐19 confirmed by reverse transcription polymerase chain reaction (RT‐PCR), and few serology results were available. What does this study add? Among 311 patients with acral lesions, mainly chilblains, during the COVID‐19 lockdown period in France, the majority of patients tested had no evidence of SARS‐CoV‐2 infection.Overall, 70 of 75 patients were seronegative for SARS‐Cov‐2 serology and 114 of 121 patients were negative for SARS‐CoV‐2 RT‐PCR. What is already known about this topic? About 1000 cases of acral lesions, mainly chilblains, were reported during the COVID‐19 outbreak.Chilblains were reported to occur in young people within 2 weeks of infectious signs, which were mild when present.Most cases did not have COVID‐19 confirmed by reverse transcription polymerase chain reaction (RT‐PCR), and few serology results were available. What does this study add? Among 311 patients with acral lesions, mainly chilblains, during the COVID‐19 lockdown period in France, the majority of patients tested had no evidence of SARS‐CoV‐2 infection.Overall, 70 of 75 patients were seronegative for SARS‐Cov‐2 serology and 114 of 121 patients were negative for SARS‐CoV‐2 RT‐PCR. Plain language summary available online [ABSTRACT FROM AUTHOR]

Khaled Ezzedine, 1 Anne Claire Fougerousse, 2, 3 Roberte Aubert, 4 Jean-Benoît Monfort, 5 Ziad Reguiaï, 3, 6 Jason Shourick, 7 Charles Taieb, 8, 9,* François Maccari 3, 10,* 1Private Pratice, La Varenne Saint Hilaire, France; 2Hôpital d’instruction des armées, Saint-Mandé, France; 3Resopso, Paris, France; 4France Psoriasis, Association de Patients, Paris, France; 5Hôpital Cochin, Paris, France; 6Service de Dermatologie, Polyclinique Courlancy-Bezannes, Reims, France; 7Université Paris Sud, Paris, France; 8Santé Publique, Hôpital Necker Enfants Malades, Paris, France; 9European Market Maintenance Assessment, Fontenay-sous-Bois, France; 10EA EpiDermE UPEC-Université Paris-Est Créteil, Creteil, France*These authors contributed equally to this workCorrespondence: Charles Taieb Tel +33 771 772 100Email charles.taieb@emma.clinicBackground: Psoriasis impacts independently of its severity on patients’ lifestyle and quality of life (QoL).Aim: To build a tool for assessing the patient-reported psoriasis burden.Methods: An expert group created a questionnaire using a standardized methodology building questionnaires assessing quality of life issues. The questionnaire was translated from French into a cultural and linguistically validated US English version.Results: A conceptual questionnaire of 54 questions was created. The confirmatory analyses resulted in a 10-feature questionnaire divided into 4 internally consistent domains with a Cronbach’s alpha coefficient of 0.9. It was reproducible and highly reliable. It correlated well with the Dermatology Life Quality Index (DLQI), Perceived Stress Scale (PSS), and SF-12 mental and SF12 physical scores.Conclusion: This tool allows for the first time to assess the burden of psoriasis patients. Its use may allow improving medical and nonmedical patient care, thus improving their daily life.Keywords: disease burden, psoriasis, quality of life, questionnaire, standardized method

In its early age, telecommunication was focused on voice communications, and acoustics was at the heart of the work related to speech coding and transmission, automatic speech recognition or speech synthesis, aiming at offering better quality (Quality of Experience or QoE) and enhanced services to users. As technology has evolved, the research themes have diversified, but acoustics remains essential. This paper gives an overview of the evolution of acoustic research for telecommunication. Communication was initially (and for a long time) only audio with a monophonic narrow-band sound (i.e. [300–3400 Hz]). After the bandwidth extension (from the wide-band [100–7000 Hz] to the full-band [20 Hz–20 kHz] range), a new break was the introduction of 3D sound, either to provide telepresence in audioconferencing or videoconferencing, or to enhance the QoE of contents such as radio, television, VOD, or video games. Loudspeaker or microphone arrays have been deployed to implement “Holophonic” or “Ambisonic” systems. The interaction between spatialized sounds and 3D images was also investigated. At the end of the 2000s, smartphones invaded our lives. Binaural sound was immediately acknowledged as the most suitable technology for reproducing 3D audio on smartphones. However, to achieve a satisfactory QoE, binaural filters need to be customized in relation with the listener’s morphology. This question is the main obstacle to a mass-market distribution of binaural sound, and its solving has prompted a large amount of work. In parallel with the development of technologies, their perceptual evaluation was an equally important area of research. In addition to conventional methods, innovative approaches have been explored for the assessment of sound spatialization, such as physiological measurement, neuroscience tools or Virtual Reality (VR). The latest development is the use of acoustics as a universal sensor for the Internet of Things (IoT) and connected environments. Microphones can be deployed, preferably with parcimony, in order to monitor surrounding sounds, with the goal of detecting information or events thanks to models of automatic sound recognition based on neural networks. Applications range from security and personal assistance to acoustic measurement of biodiversity. As for the control of environments or objects, voice commands have become widespread in recent years thanks to the tremendous progress made in speech recognition, but an even more intuitive mode based on direct control by the mind is proposed by Brain Computer Interfaces (BCIs), which rely on sensory stimulation using different modalities, among which the auditory one offers some advantages.

Background: Bone scintigraphy used as a diagnostic technique frequently yields non-specific intense uptake by vertebrae. Bone biopsy may therefore be required to establish a diagnosis in cases of Paget''s disease of bone. The aim of the study was to ascertain the sensitivity and specificity of two new images—heart sign and clover sign—in Paget''s disease of bone. Methods: Two expert rheumatologists analyzed 294 bone scintigraphies of patients with vertebral involvement: 204 without and 90 with Paget''s disease. The presence or absence of the clover or heart signs was determined in each scintigraphy. A specificity and sensitivity study was performed with the data obtained. A study of concordance was made between two radiologists blinded to the real diagnosis. Each one analyzed 120 scintigraphies for the presence and absence of the signs: 40 with Paget''s disease and clover and/or heart signs (selected from the initial 90 cases), 40 with Paget''s disease with neither sign and 40 selected from the pool of 4000 scintigraphies of patients with vertebral involvement, with images easily mistaken for these signs (vertebral collapse, osteoarthritis and bone metastases). Kappa statistics were calculated. Findings: Sensitivity of both signs for Paget''s disease of bone was low: 44% (95% CI 34.0 to 55.3). However, specificity was excellent: 100% (95% CI 98.2 to 100). Inter-radiologist concordance was almost perfect: Kappa 0.86 (95% CI 0.77 to 0.95). Interpretation: The heart and clover signs are highly specific (probably pathognomonic) of Paget''s disease of bone. In cases with doubtful radiologic images, these findings on scintigraphic vertebral images may afford a definitive diagnosis of Paget''s disease of bone and thus obviate further confirmatory invasive diagnostic procedures. [Copyright &y& Elsevier]

In this article is reported the experience of a Gerontology department in the treatment of psychological and behavioral disorders, by means of an internal day care center. Historically, the creation of a day care center, within the Gerontology departement of the Biceˆtre hospital (France), was the result of a reflection and experiences carried out for several years, about the difficult care of inpatients with psychological and behavioral disorders. The project was designed to meet the need of creating a place where these disorders might be more completely understood and treated. Given the previous experiences in this department and in others, the day care center had to reach several aims:

Hypothesis: Rhinosinusitis is common during HIV infection; its prevalence is uncertain and could probably be related to clinical features, immunoallergological status, and diagnostic criteriaMethods: Seventy-four patients hospitalized with HIV infection were prospectively evaluated for the presence of rhinosinusitis based on clinical findings, nasal endoscopy, or paranasal sinus computed tomography (CT). Immune status, nasal smear, features of atopy (based on the prick test), and its contribution to sinusal inflammatory pathology were also evaluated.Results: Most patients were severely immunosuppressed: CD4+ 155+/-201 cells/mL and 12+/-11% (mean +/- SD). Thirty-five percent of the patients presented at least two criteria of rhinosinusitis (clinical findings, nasal endoscopy, and CT: 35%; clinical findings and CT: 50%; nasal endoscopy and CT: 15%). CT scan showed multiple sinus involvement, opacification over 25% of the total volume of the maxillary sinus in 50% of patients, and opacification of the sphenoidal sinus in 40% of cases. Atopy was present in 18% of patients, a figure which reflects the expected prevalence in our geographic area. Two independent predictors were associated with a higher probability of rhinosinusitis: bilateral absence of maxillary infundibular patency (odds ratio, 7.5; 95% CI = 2.03-27.9) and low total count (odds ratio, 0.99; 95% CI = 0.99-1.00) or percentage of CD4+ (odds ratio, 0.93; 95% CI = 0.88-1.00).Conclusions: There is a high prevalence of rhinosinusitis in HIV-infected individuals. This finding is related to a decreased cellular immunity, but it does not appear to be related to IgE-related immediate hypersensitivity. Nasal endoscopy should be the first-step diagnostic test. However, when clinical suspicion exists and endoscopy fails to explain symptoms, CT scan is a valuable adjunct to establish this diagnosis. [ABSTRACT FROM AUTHOR]