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1.
Phys Rev E ; 107(4-2): 045306, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37198775

RESUMEN

The numerical instability of the lattice Boltzmann method (LBM) at high Mach or high Reynolds number flow is well identified, and it remains a major barrier to its application in more complex configurations such as moving geometries. This work combines the compressible lattice Boltzmann model with rotating overset grids (the so-called Chimera method, sliding mesh, or moving reference frame) for high Mach flows. This paper proposes to use the compressible hybrid recursive regularized collision model with fictitious forces (or inertial forces) in a noninertial rotating reference frame. Also, polynomial interpolations are investigated, which allow fixed inertial and rotating noninertial grids to communicate with each other. We suggest a way to effectively couple the LBM with the MUSCL-Hancock scheme in the rotating grid, which is needed to account for thermal effect of compressible flow. As a result, this approach is demonstrated to have an extended Mach stability limit for the rotating grid. It also demonstrates that this complex LBM scheme can maintain the second-order accuracy of the classic LBM by appropriately using numerical methods like polynomial interpolations and the MUSCL-Hancock scheme. Furthermore, the method shows a very good agreement on aerodynamic coefficients compared to experiments and the conventional finite-volume scheme. This work presents a thorough academic validation and error analysis of the LBM for simulating moving geometries in high Mach compressible flows.

2.
Phys Rev E ; 100(4-1): 042405, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31770869

RESUMEN

The coordinated beating of epithelial cilia in human lungs is a fascinating problem from the hydrodynamics perspective. The phase lag between neighboring cilia is able to generate collective cilia motions, known as metachronal waves. Different kinds of waves can occur, antiplectic or symplectic, depending on the direction of the wave with respect to the flow direction. It is shown here, using a coupled lattice Boltzmann-immersed boundary solver, that the key mechanism responsible for their transport efficiency is a blowing-suction effect that displaces the interface between the periciliary liquid and the mucus phase. The contribution of this mechanism on the average flow generated by the cilia is compared to the contribution of the lubrication effect. The results reveal that the interface displacement is the main mechanism responsible for the better efficiency of antiplectic metachronal waves over symplectic ones to transport bronchial mucus. The conclusions drawn here can be extended to any two-layer fluid configuration having different viscosities, and put into motion by cilia-shaped or comb-plate structures, having a back-and-forth motion with phase lags.


Asunto(s)
Bronquios/citología , Cilios/metabolismo , Modelos Biológicos , Moco/citología , Transporte Biológico
3.
Phys Rev Lett ; 121(16): 161801, 2018 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-30387650

RESUMEN

The reactor antineutrino anomaly might be explained by the oscillation of reactor antineutrinos toward a sterile neutrino of eV mass. In order to explore this hypothesis, the STEREO experiment measures the antineutrino energy spectrum in six different detector cells covering baselines between 9 and 11 m from the compact core of the ILL research reactor. In this Letter, results from 66 days of reactor turned on and 138 days of reactor turned off are reported. A novel method to extract the antineutrino rates has been developed based on the distribution of the pulse shape discrimination parameter. The test of a new oscillation toward a sterile neutrino is performed by comparing ratios of cells, independent of absolute normalization and of the prediction of the reactor spectrum. The results are found to be compatible with the null oscillation hypothesis and the best fit of the reactor antineutrino anomaly is excluded at 97.5% C.L.

4.
Phys Rev Lett ; 120(21): 211801, 2018 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-29883136

RESUMEN

The OPERA experiment was designed to study ν_{µ}→ν_{τ} oscillations in the appearance mode in the CERN to Gran Sasso Neutrino beam (CNGS). In this Letter, we report the final analysis of the full data sample collected between 2008 and 2012, corresponding to 17.97×10^{19} protons on target. Selection criteria looser than in previous analyses have produced ten ν_{τ} candidate events, thus reducing the statistical uncertainty in the measurement of the oscillation parameters and of ν_{τ} properties. A multivariate approach for event identification has been applied to the candidate events and the discovery of ν_{τ} appearance is confirmed with an improved significance level of 6.1σ. |Δm_{32}^{2}| has been measured, in appearance mode, with an accuracy of 20%. The measurement of the ν_{τ} charged-current cross section, for the first time with a negligible contamination from ν[over ¯]_{τ}, and the first direct evidence for the ν_{τ} lepton number are also reported.

6.
J Biomed Mater Res A ; 105(11): 3025-3033, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28758330

RESUMEN

In this article, dynamic viscosity, surface tension, density, heat capacity and thermal conductivity, of a bronchial mucus simulant proposed by Zahm et al., Eur Respir J 1991; 4: 311-315 were experiementally determined. This simulant is mainly composed of a galactomannan gum and a scleroglucan. It was shown that thermophysical properties of synthetic mucus are dependant of scleroglucan concentrations. More importantly and for some scleroglucan concentrations, the syntetic mucus, exhibits, somehow, comparable thermophysical properties to real bronchial mucus. An insight on the microstructure of this simulant is proposed and the different properties enounced previously have been measured for various scleroglucan concentrations and over a certain range of operating temperatures. This synthetic mucus is found to mimic well the rheological behavior and the surface tension of real mucus for different pathologies. Density and thermal properties have been measured for the first time. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 3025-3033, 2017.


Asunto(s)
Bronquios/química , Glucanos/química , Mananos/química , Moco/química , Galactosa/análogos & derivados , Humanos , Reología , Tensión Superficial , Conductividad Térmica , Viscosidad
7.
Oncogene ; 35(9): 1080-9, 2016 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-26028031

RESUMEN

Pheochromocytomas (PCC) and paragangliomas (PGL) are rare neuroendocrine tumors of neural crest origin. These tumors are caused by germline or somatic mutations in known susceptibility genes in up to 70% of cases. Over the past few years, the emergence of high-throughput technologies has enabled the unprecedented characterization of genomic alterations in PCC/PGL, and has improved our understanding of the molecular mechanisms that distinguish the different tumor subtypes. Integrated genomic analyses have shown that the mutation status of PCC/PGL susceptibility genes strongly correlates with multi-omics data. These observations not only emphasize the role of the long-standing susceptibility genes as the main drivers of PCC/PGL tumorigenesis, but also illustrate the functional interdependence between genomic and epigenomic alterations. In this review, we discuss the genomic landscape underlying PCC/PGL, its functional consequences for tumorigenesis and tumor progression, and the potential clinical relevance of this knowledge for the application of precision medicine for patients with PCC/PGL.


Asunto(s)
Genómica , Tumores Neuroendocrinos/genética , Paraganglioma/genética , Feocromocitoma/genética , Exoma , Predisposición Genética a la Enfermedad , Humanos , Mutación , Tumores Neuroendocrinos/patología , Paraganglioma/patología , Feocromocitoma/patología
8.
Ann Fr Anesth Reanim ; 32(5): 347-54, 2013 May.
Artículo en Francés | MEDLINE | ID: mdl-23669254

RESUMEN

Intraosseous infusion is an old knowledge, abandoned in the 1950s in favor of the peripheral vein, and it was essentially described in pediatrics and military medicine. Since 2005, this way is experiencing a resurgence of interest in emergency medicine particularly in adults after the failure's installation of a peripheral vein in order not to waste the time of care and administration of treatment. New devices that allow intraosseous infusion are currently used in humans. We propose to review the different kind of catheters used, to know the main technical characteristics, indications, contraindications and potential complications. We propose a comparison with the peripheral vein and a comparison between the different catheters.


Asunto(s)
Infusiones Intraóseas , Adulto , Huesos/irrigación sanguínea , Catéteres/economía , Contraindicaciones , Urgencias Médicas , Diseño de Equipo , Fracturas Óseas , Humanos , Soluciones Hipertónicas , Infusiones Intraóseas/efectos adversos , Infusiones Intraóseas/economía , Infusiones Intraóseas/instrumentación , Infusiones Intraóseas/métodos , Infusiones Intraóseas/tendencias , Agujas/economía , Especificidad de Órganos , Osteítis , Instrumentos Quirúrgicos/economía
9.
Eur Ann Otorhinolaryngol Head Neck Dis ; 129(6): 315-8, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23078982

RESUMEN

Over the last decade, it has been clearly established that one-third of all paragangliomas are genetically determined. Genetic testing, guided by the family history and clinical findings, must now be proposed to all subjects undergoing surgery for head and neck paraganglioma. When a mutation is identified on one of the susceptibility genes (SDHD, SDHB, SDHC, SDHAF2, VHL), at-risk subjects should be investigated for the presence of other supra- and infradiaphragmatic paragangliomas and functional catecholamine-secreting paragangliomas and/or phaeochromocytomas. Identification of a germline mutation on the SDHB gene is a high-risk factor for malignancy and poor prognosis and requires close surveillance of subjects carrying this mutation. The diagnosis of hereditary paraganglioma also allows predictive genetic screening in first-degree relatives of the index subject. Genetic testing for paraganglioma is therefore now an important component of the diagnostic and therapeutic management of these patients.


Asunto(s)
Neoplasias de Cabeza y Cuello/genética , Paraganglioma/genética , Humanos
13.
Horm Metab Res ; 44(5): 359-66, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22517557

RESUMEN

The identification of 9 susceptibility genes for paraganglioma/pheochromocytoma between 2001 and 2010 has led to the development of routine genetic tests. To study the evolution in genetic screening for paraganglioma/pheochromocytoma over the past decade, we carried out a retrospective study on the tests performed in our laboratory from January 2001 to December 2010. A genetic test for paraganglioma/pheochromocytoma was assessed for 2 499 subjects, 1 620 index cases, and 879 presymptomatic familial genetic tests. A germline mutation in a PGL/PCC susceptibility gene was identified in 363 index cases (22.4%): 269 in SDHx genes (137 in SDHB, 100 in SDHD, 30 in SDHC, 2 in SDHA), 64 in VHL, 23 in RET, and 7 in TMEM127. A presymptomatic paraganglioma/pheochromocytoma test was positive in 427 subjects. Advances in molecular screening techniques led to an increase in the total number of mutation-carriers diagnosed each year. Overall, during the last decade, our laboratory identified a germline mutation in 44.7% of patients with a suspect hereditary PGL/PCC and in 8% of patients with an apparently sporadic PGL/PCC. During the past decade, the discoveries of new paraganglioma/pheochromocytoma susceptibility genes and the subsequent progress of molecular screening techniques have enabled us to diagnose a hereditary paraganglioma/pheochromocytoma in about 22% of patients tested in routine practice. This genetic testing is of major importance for the follow-up of affected patients and for the genetic counselling of their families.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/genética , Pruebas Genéticas , Paraganglioma/genética , Feocromocitoma/genética , Neoplasias de las Glándulas Suprarrenales/diagnóstico , Biomarcadores de Tumor/genética , Predisposición Genética a la Enfermedad , Pruebas Genéticas/historia , Historia del Siglo XXI , Humanos , Paraganglioma/diagnóstico , Feocromocitoma/diagnóstico
18.
Ann Fr Anesth Reanim ; 28(1): 82-5, 2009 Jan.
Artículo en Francés | MEDLINE | ID: mdl-19144494

RESUMEN

We report the case of a severe acute asthma, which required, after optimal medical therapy, helium and sevoflurane CO-administration after tracheal intubation. The Anesthetic Conserving Device allowed sevoflurane use with intensive care unit's ventilator. The helium-sevoflurane association was maintained during 9 days to decrease the bronchospasm, waiting for the efficiency of an aetiologic treatment. We discuss the suitability of this association to treat severe acute asthma, and its administration modalities.


Asunto(s)
Anestésicos por Inhalación/uso terapéutico , Asma/tratamiento farmacológico , Helio/uso terapéutico , Éteres Metílicos/uso terapéutico , Acidosis Respiratoria/tratamiento farmacológico , Acidosis Respiratoria/etiología , Enfermedad Aguda , Anestésicos por Inhalación/administración & dosificación , Espasmo Bronquial/tratamiento farmacológico , Combinación de Medicamentos , Femenino , Helio/administración & dosificación , Humanos , Hipercapnia/sangre , Intubación Intratraqueal , Éteres Metílicos/administración & dosificación , Persona de Mediana Edad , Sevoflurano , Ventiladores Mecánicos
19.
Eur J Gynaecol Oncol ; 30(6): 609-15, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-20099488

RESUMEN

PURPOSE OF INVESTIGATION: To evaluate the prognostic significance for overall survival rate for the marker combination TPS and CA125 in ovarian cancer patients after three chemotherapy courses during long-term clinical follow-up. METHODS: The overall survival of 212 (out of 213) ovarian cancer patients (FIGO Stages I-IV) was analyzed in a prospective multicenter study during a 10-year clinical follow-up by univariate and multivariate analysis. RESULTS: In patients with ovarian cancer FIGO Stage I (34 patients) or FIGO Stage II (30 patients) disease, the univariate and multivariate analysis of the 10-year overall survival data showed that CA125 and TPS serum levels were not independent prognostic factors. In the FIGO Stage III group (112 patients), the 10-year overall survival was 15.2%; while in the FIGO Stage IV group (36 patients) a 10-year overall survival of 5.6% was seen. Here, the tumor markers CA125 and TPS levels were significant prognostic factors in both univariate and multivariate analysis (p < 0.0001). In a combined FIGO Stage III + FIGO Stage IV group (60 patients with optimal debulking surgery), multivariate analysis demonstrated that CA125 and TPS levels were independent prognostic factors. For patients in this combined FIGO Stage III + IV group having both markers below respective discrimination level, 35.3% survived for more than ten years, as opposed to patients having one marker above the discrimination level where the 10-year survival was reduced to 10% of the patients. For patients showing both markers above the respective discrimination level, none of the patients survived for the 10-year follow-up time. CONCLUSION: In FIGO III and IV ovarian cancer patients, only patients with CA 125 and TPS markers below the discrimination level after three chemotherapy courses indicated a favorable prognosis. Patients with an elevated level of CA 125 or TPS or both markers after three chemotherapy courses showed unfavorable prognosis.


Asunto(s)
Antineoplásicos/administración & dosificación , Antígeno Ca-125/sangre , Neoplasias Ováricas/sangre , Neoplasias Ováricas/tratamiento farmacológico , Péptidos/sangre , Anciano , Esquema de Medicación , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Ováricas/cirugía , Pronóstico , Análisis de Supervivencia
20.
J Chir (Paris) ; 144(5): 449-51, 2007.
Artículo en Francés | MEDLINE | ID: mdl-18065906

RESUMEN

The nonspecific colon ulcer is a not a well-known disorder. A case of ulcer of the colic hepatic flexure is described. It was a case of pseudotumor and the pathological examination confirmed the diagnosis. The precise diagnosis of colon ulcer is useful for conservative treatment with coloscopic surveillance and to prevent a hemorrhagic complication or peritonitis after perforation. Contrary to diverticulitis, this pathology is most dominant on the right colon and particularly on the cecum. This explains the frequency of pseudoappendicular syndromes.


Asunto(s)
Enfermedades del Colon/diagnóstico , Úlcera/diagnóstico , Biopsia , Enfermedades del Colon/cirugía , Colonoscopía , Femenino , Humanos , Persona de Mediana Edad , Úlcera/cirugía
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