On the coherence of synthetic turbulence generation methods

Synthetic turbulence generation methods have been extensively used by engineers and scientists in the past ten years in order to impose initial conditions in a wide range of turbulent flow problems. The interest in synthetic methods relies in the fact that reliability of methodologies such as large eddy simulation (LES) or direct numerical simulation (DNS) strongly depends on how well the developed turbulence is characterized, which generally leads to computationally expensive simulations. In this work the methodology known as “modified discretizing and synthesizing random flow generation” (MDSRFG) jointly with a LES method is analyzed for its use in the study of bluff body aerodynamics. A comparison with other generation techniques, that are closely related by their features and their conceptual origins, is presented with particular emphasis on the correct representation of the coherence of the velocity field. The resulting wind loads on the model, along with the statistical characteristics of the flow, show that the MDSRFG technique allows to represent a field of spatially correlated velocities correctly.Publicado en: Mecánica Computacional vol. XXXV, no. 18Facultad de Ingenierí

On the coherence of synthetic turbulence generation methods

Synthetic turbulence generation methods have been extensively used by engineers and scientists in the past ten years in order to impose initial conditions in a wide range of turbulent flow problems. The interest in synthetic methods relies in the fact that reliability of methodologies such as large eddy simulation (LES) or direct numerical simulation (DNS) strongly depends on how well the developed turbulence is characterized, which generally leads to computationally expensive simulations. In this work the methodology known as “modified discretizing and synthesizing random flow generation” (MDSRFG) jointly with a LES method is analyzed for its use in the study of bluff body aerodynamics. A comparison with other generation techniques, that are closely related by their features and their conceptual origins, is presented with particular emphasis on the correct representation of the coherence of the velocity field. The resulting wind loads on the model, along with the statistical characteristics of the flow, show that the MDSRFG technique allows to represent a field of spatially correlated velocities correctly.Publicado en: Mecánica Computacional vol. XXXV, no. 18Facultad de Ingenierí

Ganglion intraneural del nervio cubital: presentación de un caso

Se presenta un caso de un Tumor del Nervio Cubital que suele conocerse en la literatura como Ganglion Intraneural o Quiste mucoide de los nervios, y que es capaz de producir parálisis sensitiva y nerviosa. Se intenta diferenciarlos de los Gangliones sinoviales a través de un estudio de la bibliografía de todas las épocas, considerándose que se trata de degeneraciones del tejido conjuntivo nervioso que conducen a la metaplasia del tejido de sostén endo y perineural con vacuolización de los fibroblastos y producción de sustancia mucoide. En la revisión bibliográfica realizada no se encuentran más de una decena de casos con localización en el miembro superior y en el nervio cubital. Se esbozan los criterios de diagnóstico diferencial con otras minoraciones y lesiones de los nervios y se indica como tratamiento recomendable la exéresis quirúrgica.A case of Ganglion Mucoid Cyst of the Ulnar Nerve producing combined motor and sensory deficit is reported. Inthe bibliographic study is possible to do the differential diagnosis between this specific tumor and the common Ganglia of the tendon sheath. Its origine may be the neural conjuntive tissue degeneration whit subsecuent endo and perineural tissue metaplasia, fibroblastic cyst and production of mucoide substance. There are not more than ten similar cases published in the literature. Its diferential diagnosis and recomended treatment is presented

Treatment options beyond immunotherapy in patients with wild-type lung adenocarcinoma: a Delphi consensus

Purpose: Immunotherapy-based approaches are standard first-line treatments for advanced/metastatic lung cancer or for chemoradiotherapy consolidation in locally advanced disease. Uncertainty on how to treat patients at disease progression prompted us to develop a consensus document on post-immunotherapy options in Spain for patients with advanced wild-type lung adenocarcinoma. Methods: After extensive literature review, a 5-member scientific committee generated 33 statements in 4 domains: general aspects (n = 4); post-durvalumab in locally advanced disease (n = 6); post-first-line immunotherapy ± chemotherapy in advanced/metastatic disease (n = 11); and post-first-line platinum-based chemotherapy in advanced/metastatic disease (n = 12). A panel of 26 lung cancer experts completed 2 Delphi iterations through an online platform rating their degree of agreement/disagreement (first-round scale 1–5 and second-round scale 1–4, 1 = strongly disagree, 4/5 = strongly agree) for each statement. Second-round consensus: ≥ 70% of responses were in categories 1/2 (disagreement) or 3/4 (agreement). Results: Consensus was reached for 2/33 statements in the first Delphi round and in 29/31 statements in the second round. Important variables informing treatment at disease progression with an immunotherapy-based treatment include: disease aggressiveness, previous treatment, accumulated toxicity, progression-free interval, PD-L1 expression, and tumour mutational burden. A platinum-based chemotherapy should follow a first-line immunotherapy treatment without chemotherapy. Treatment with docetaxel + nintedanib may be appropriate post-durvalumab in refractory patients or following progression to first-line chemotherapy + immunotherapy, or second-line chemotherapy after first-line immunotherapy, or first-line chemotherapy in some patients with low/negative PD-L1 expression, or second-line immunotherapy after first-line chemotherapy. Conclusions: To support decision making following progression to immunotherapy-based treatment in patients with advanced wild-type lung adenocarcinoma, a consensus document has been developed.The project was funded by Boehringer Ingelheim

Whipple's Disease With Neurological Manifestations: Case Report

Whipple's disease (WD) is an uncommon multisystem condition caused by the bacillus Tropheryma whipplei. Central nervous system involvement is a classical feature of the disease observed in 20 to 40% of the patients. We report the case of a 62 yeards old man with WD that developed neurological manifestations during its course, and discuss the most usual signs and symptoms focusing on recent diagnostic criteria and novel treatment regimens.622 A342346Whipple, G.H., A hitherto undescribed disease characterized anatomically by deposits of fat and fatty acids in the intestinal and mesenteric lymphatic tissues (1907) Johns Hopkins Hosp Bull, 18, pp. 382-391Marth, T., Raoult, D., Whipple's disease (2003) Lancet, 36, pp. 239-246Gerard, A., Sarrot-Reynauld, F., Liozon, E., Neurologic presentation of Whipple disease: Report of 12 cases and review of the literature (2002) Medicine (Baltimore), 81, pp. 443-457Brown, A.P., Lane, J.C., Murayama, S., Vollmer, D.G., Whipple's disease presenting with isolated neurological symptoms: Case report (1990) J Neurosurg, 73, pp. 623-627Bostwick, D.G., Bensch, K.G., Burke, J.S., Whipple's disease presenting as aortic insufficiency (1981) N Engl J Med, 305, pp. 995-998Raoult, D., A febrile, blood culture-negative endocarditis (1999) Ann Intern Med, 131, pp. 144-146Chan, R.Y., Yannuzzi, L.A., Foster, C.S., Ocular Whipple's disease: Earlier definitive diagnosis (2001) Ophthalmology, 108, pp. 2225-2231Louis, E.D., Lynch, T., Kaufmann, P., Fahn, S., Odel, J., Diagnostic guidelines in central nervous system Whipple's disease (1996) Ann Neurol, 40, pp. 561-568Sieracki, J.C., Whipple's disease: Observations on systemic involvement (1958) Amer Med Asso Arch Pathol, 66, pp. 464-467Anderson, M., Neurology of Whipple's disease (2000) J Neurol Neurosurg Psychiatry, 68, pp. 2-5De Coene, B., Gilliard, C., Indekeu, P., Whipple's disease confined to the central nervous system (1996) Neuroradiology, 38, pp. 325-327Verhagen, W.I.M., Huygen, P.L.M., Dalman, J.E., Schuurmans, M.M.J., Whipple's disease and the central nervous system: A case report and a review of the literature (1996) Clin Neurol Neurosurg, 98, pp. 299-304Feldman, M., Hendler, R.S., Morrison, E.B., Acute meningoencephalitis after withdrawal of antibiotics in Whipple's disease (1980) Ann Intern Med, 93, pp. 709-711Schwartz, M.A., Selhorst, J.B., Ochs, A.L., Oculomasticatory myorhythmia: A unique movement disorder occurring in Whipple's disease (1986) Ann Neurol, 20, pp. 677-683Manzel, K., Tranel, D., Cooper, G., Cognitive and behavioral abnormalities in a case of central nervous system Whipple disease (2000) Arch Neurol, 57, pp. 399-403Halperin, J.J., Landis, D.M., Kleinman, G.M., Whipple's disease of the nervous system (1982) Neurology, 32, pp. 612-617Feurle, G.E., Volk, B., Waldherr, R., Cerebral Whipple's disease with negative jejunal histology (1979) N Engl J Med, 300, pp. 907-908Madoule, P., Ciaudio-Lacroix, C., Halimi, P., Osteoarticular lesions in Whipple's disease, a propos of a destructive form and review of the literature (1985) J Radiol, 66, pp. 345-350Brändle, M., Ammann, P., Spinas, G.A., Relapsing Whipple's disease presenting with hypopituitarism (1999) Clin Endocrinol, 50, pp. 399-403Topper, R., Gartung, C., Block, F., Neurologic complications in inflammatory bowel diseases (2002) Nervenarzt, 73, pp. 489-499Clarke, C.E., Falope, Z.F., Abdelhadi, H.A., Cervical myelopathy caused by Whipple's disease (1998) Neurology, 50, pp. 1505-1506Ramzan, N.N., Loftus, E., Burgart, L.J., Diagnosis and monitoring of Whipple disease by polymerase chain reaction (1997) Ann Intern Med, 126, pp. 520-527Von Herbay, A., Ditton, H.J., Scuhmacher, F., Whipple's disease: Staging and monitoring by cytology and polymerase chain reaction analysis of cerebrospinal fluid (1997) Gastroenterology, 113, pp. 434-441Kremer, S., Besson, G., Bonaz, B., Pasquier, B., Le Bas, J.F., Grand, S., Diffuse lesions in the CNS revealed by MR imaging in a case of Whipple disease (2001) Am J Neuroradiol, 22, pp. 493-495Romanul, F.C., Radvany, J., Rosales, R.K., Whipple's disease confined to the brain: A case studied clinically and pathologically (1977) J Neurol Neurosurg Psychiatry, 40, pp. 901-909Thompson, D.G., Leidingham, J.M., Howard, A.J., Brown, C.L., Meningitis in Whipple's disease (1978) BMJ, 2, pp. 14-15Feurle, G.E., Marth, T., An evaluation of antimicrobial treatment for Whipple's disease: Tetracycline versus trimethoprim-sulfamethoxazole (1994) Dig Dis Sci, 39, pp. 1642-1648Misbah, S.A., Mapstone, N.P., Whipple's disease revisited (2000) J Clin Pathol, 53, pp. 750-755Schnider, P.J., Reisinger, E.C., Berger, T., Krejs, G.J., Auff, E., Treatment guidelines in central nervous system Whipple's disease (1997) Ann Neurol, 41, pp. 561-56

Simulación computacional del cuerpo de Ahmed bajo distintos ángulos de incidencia de viento

En este trabajo se presenta el análisis computacional del flujo de viento alrededor del modelo simplificado conocido como “cuerpo de Ahmed”, bajo distintos ángulos de incidencia. La geometría estudiada del cuerpo corresponde a un ángulo de inclinación de cola de treinta y cinco grados. Se discute sobre la convergencia de mallado para las distintas configuraciones consideradas, las cuales corresponden a distintos ángulos de incidencia del viento sobre el cuerpo. La simulación computacional se lleva a cabo utilizando el código libre y abierto OpenFOAM (Open Field Operation and Manipulation). Se obtienen los coeficientes aerodinámicos, perfiles de velocidad, los cuales resultan concordantes con reportes experimentales de referencias bibliográficas específicas. Se realiza además un post-proceso para determinar las estructuras vorticosas y posterior análisis de la contribución de las distintas componentes del cuerpo en su formación.Publicado en: Mecánica Computacional vol. XXXV, no. 17Facultad de Ingenierí

Simulación computacional del cuerpo de Ahmed bajo distintos ángulos de incidencia de viento

En este trabajo se presenta el análisis computacional del flujo de viento alrededor del modelo simplificado conocido como “cuerpo de Ahmed”, bajo distintos ángulos de incidencia. La geometría estudiada del cuerpo corresponde a un ángulo de inclinación de cola de treinta y cinco grados. Se discute sobre la convergencia de mallado para las distintas configuraciones consideradas, las cuales corresponden a distintos ángulos de incidencia del viento sobre el cuerpo. La simulación computacional se lleva a cabo utilizando el código libre y abierto OpenFOAM (Open Field Operation and Manipulation). Se obtienen los coeficientes aerodinámicos, perfiles de velocidad, los cuales resultan concordantes con reportes experimentales de referencias bibliográficas específicas. Se realiza además un post-proceso para determinar las estructuras vorticosas y posterior análisis de la contribución de las distintas componentes del cuerpo en su formación.Publicado en: Mecánica Computacional vol. XXXV, no. 17Facultad de Ingenierí

Simulación computacional del cuerpo de Ahmed bajo distintos ángulos de incidencia de viento

En este trabajo se presenta el análisis computacional del flujo de viento alrededor del modelo simplificado conocido como “cuerpo de Ahmed”, bajo distintos ángulos de incidencia. La geometría estudiada del cuerpo corresponde a un ángulo de inclinación de cola de treinta y cinco grados. Se discute sobre la convergencia de mallado para las distintas configuraciones consideradas, las cuales corresponden a distintos ángulos de incidencia del viento sobre el cuerpo. La simulación computacional se lleva a cabo utilizando el código libre y abierto OpenFOAM (OpenField Operation and Manipulation). Se obtienen los coeficientes aerodinámicos, perfiles de velocidad, los cuales resultan concordantes con reportes experimentales de referencias bibliográficas específicas.Se realiza además un post-proceso para determinar las estructuras vorticosas y posterior análisis de la contribución de las distintas componentes del cuerpo en su formación.Publicado en: Mecánica Computacional vol. XXXV no.47Facultad de Ingenierí