Spectral problem for the complex mKdV equation: singular manifold method and Lie symmetries

This article addresses the study of the complex version of the modified Korteweg-de Vries equation using two different approaches. Firstly, the singular manifold method is applied in order to obtain the associated spectral problem, binary Darboux transformations and $\tau$-functions. The second part concerns the identification of the classical Lie symmetries for the spectral problem. The similarity reductions associated to these symmetries allow us to derive the reduced spectral problems and first integrals for the ordinary differential equations arising from such reductions.Comment: This article is intended to be published in the special issue dedicated to Prof. Decio Levi (in Open Communications in Nonlinear Mathematical Physics

Permanencia del gravamen a los movimientos financieros en Colombia

Un impuesto es una carga obligatoria que se genera hacia un acreedor fiscal, se encuentra conformado por un sujeto activo quien es la persona que tiene la tarea de recaudar, el sujeto pasivo que es la persona natural o jurídica sobre la cual recae la obligación tributaria, un hecho que genera la obligación de pagar el impuesto, una base gravable, una tarifa y su causación (Miranda, 2018) per se con los impuestos no necesariamente el contribuyente obtiene un servicio o una ganancia para sí, por consiguiente esta es una de las características principales que se pueden encontrar dentro de los impuestos, es que se pagan pero no necesariamente quien lo paga recibe para sí una contraprestación directa, si no que se recibe una contraprestación a diferentes aspectos, necesidades o problemas que se deben suplir dentro de la sociedad como: la educación, la infraestructura, el agro, la economía entre otros aspectos. La economía es el caso del presente trabajo, en 1998 el presidente de la república de Colombia Andrés Pastrana Arango vigente en dicho tiempo en ejercicio de las facultades que le confiere el artículo 215 de la constitución política junto con lo previsto en la ley 137 de 1994 declara estado de emergencia económica y social por medio del decreto 2330 de 1998 debido a que Colombia se encontraba atravesando por una crisis financiera internacional, en donde se observó una gran caída del flujo de los capitales externos en Colombia, crisis en donde las inversiones financieras se vieron disminuidas por diferentes problemas a nivel internacional, las entidades financieras nacionales habían agotado todos los recursos necesarios para poder solventar los problemas que se estaban produciendo en Colombia a raíz de esta crisis, sin embargo se necesitó implementar el decreto de estado de emergencia económica y social para poder mitigar el menoscabo ocasionado por la crisis financiera internacional y poder resolver y brindarle solidez a la situación de los sectores financieros y cooperativos en Colombia.A tax is a mandatory charge that is generated towards a tax creditor, it is made up of an active subject who is the person who has the task of collecting, the taxpayer that is the natural or legal person on whom the tax obligation rests, a fact that generates the obligation to pay the tax, a taxable base, a fee and its causation (Miranda, 2018) per se with taxes not necessarily the taxpayer obtains a service or a profit for himself, therefore this is one of the main characteristics that can be found within taxes, is that they are paid but not necessarily whoever pays receives for himself a direct consideration, if not that a consideration is received to different aspects, needs or problems that must be met within society as: education, infrastructure, agriculture, economics among other aspects. The economy is the case of the present work, in 1998 the president of the Republic of Colombia Andrés Pastrana Arango in force at that time in exercise of the powers conferred on him by article 215 of the political constitution along with the provisions of law 137 of 1994 declares a state of economic and social emergency through decree 2330 of 1998 because Colombia was going through an international financial crisis, where there was a large drop in the flow of external capital in Colombia, a crisis in which financial investments saw diminished by different problems at international level, the national financial entities had exhausted all the necessary resources to be able to solve the problems that were taking place in Colombia as a result of this crisis, nevertheless it was necessary to implement the decree of state of economic and social emergency in order to mitigate the impairment caused by the financial crisis int and to be able to resolve and provide solidity to the situation of the financial and cooperative sectors in Colombia

Barcelona OpenMP tasks suite: a set of benchmarks targeting the exploitation of task parallelism in OpenMP

Traditional parallel applications have exploited regular parallelism, based on parallel loops. Only a few applications exploit sections parallelism. With the release of the new OpenMP specification (3.0), this programming model supports tasking. Parallel tasks allow the exploitation of irregular parallelism, but there is a lack of benchmarks exploiting tasks in OpenMP. With the current (and projected) multicore architectures that offer many more alternatives to execute parallel applications than traditional SMP machines, this kind of parallelism is increasingly important. And so, the need to have some set of benchmarks to evaluate it. In this paper, we motivate the need of having such a benchmarks suite, for irregular and/or recursive task parallelism. We present our proposal, the Barcelona OpenMP Tasks Suite (BOTS), with a set of applications exploiting regular and irregular parallelism, based on tasks. We present an overall evaluation of the BOTS benchmarks in an Altix system and we discuss some of the different experiments that can be done with the different compilation and runtime alternatives of the benchmarks.Peer ReviewedPostprint (published version

Experiences parallelizing a web server with OpenMP

Multi-threaded web servers are typically parallelized by hand using the pthreads library. OpenMP has rarely been used to parallelize such kind of applications, although we foresee that it can be a great tool for network servers developers. In this paper we compare how easy is to parallelize the Boa web server using OpenMP, compared to a pthreads parallelization, and the performance achieved. We present the results of a parallelization based on OpenMP 2.0, the dynamic sections model and pthreads.Peer ReviewedPostprint (published version

Functional Interaction between Human Papillomavirus Type 16 E6 and E7 Oncoproteins and Cigarette Smoke Components in Lung Epithelial Cells

The smoking habit is the most important, but not a sufficient cause for lung cancer development. Several studies have reported the human papillomavirus type 16 (HPV16) presence and E6 and E7 transcripts expression in lung carcinoma cases from different geographical regions. The possible interaction between HPV infection and smoke carcinogens, however, remains unclear. In this study we address a potential cooperation between tobacco smoke and HPV16 E6 and E7 oncoproteins for alterations in proliferative and tumorigenic properties of lung epithelial cells. A549 (alveolar, tumoral) and BEAS-2B (bronchial, non-tumoral) cell lines were stably transfected with recombinant pLXSN vectors expressing HPV16 E6 and E7 oncoproteins and exposed to cigarette smoke condensate (CSC) at different concentrations. HPV16 E6 and E7 expression was associated with loss of p53 stability, telomerase (hTERT) and p16INK4A overexpression in BEAS-2B cells as demonstrated by quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting (WB). In A549 cells we observed downregulation of p53 but not a significant increase of hTERT transcripts. In addition, the HPV16 E6/E7 transfected cell lines showed an increased proliferation rate and anchorage-independent growth in a HPV16 E6 and E7 expression-dependent manner. Moreover, both HPV16 E6/E7 and mock transfected cells showed an increased proliferation rate and anchorage-independent growth in the presence of 0.1 and 10 µg/mL CSC. However, this increase was significantly greater in HPV16 E6/E7 transfected cells (p<0.001). Data were confirmed by FCSE proliferation assay. The results obtained in this study are suggestive of a functional interaction between tobacco smoke and HPV16 E6/E7 oncoproteins for malignant transformation and tumorigenesis of lung epithelial cells. More studies are warranted in order to dissect the molecular mechanisms involved in this cooperation

¿Beneficios económicos periódicos: Una alternativa para la vejez digna de los más vulnerables?

Mediante el Acto Legislativo 01 de 2005 y la Ley 1328 de 2009, se ideó la manera de conceder beneficios económicos periódicos inferiores al salario mínimo a personas de escasos recursos que no cumplan con las condiciones requeridas para tener derecho a una pensión y que hayan realizado aportes o ahorros periódicos o esporádicos a través del medio o mecanismo de ahorro determinados por el Gobierno Nacional. El mecanismo de Beneficios Económicos Periódicos (BEP a partir de ahora) se define así: es un Servicio Social Complementario que hace parte del Sistema de Protección a la Vejez y constituye una alternativa para la protección a largo plazo de las personas, uniendo el esfuerzo de ahorro que realicen por medio de este mecanismo, con el subsidio o incentivo entregado por parte del Estado, materializándose así los principios de participación y solidarida

Increased 1-year mortality in haemodialysis patients with COVID-19: A prospective, observational study

Background: Dialysis confers the highest risk of coronavirus disease 2019 (COVID-19) death among comorbidities predisposing to severe COVID-19. However, reports of COVID-19-associated mortality frequently refer to mortality during the initial hospitalization or first month after diagnosis. Methods: In a prospective, observational study, we analysed the long-term (1-year follow-up) serological and clinical outcomes of 56 haemodialysis (HD) patients who were infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during the first pandemic wave. COVID-19 was diagnosed by a positive polymerase chain reaction (PCR) test (n = 37) or by the development of anti-SARS-CoV-2 antibodies (n = 19). Results: After >1 year of follow-up, 35.7% of HD patients infected by SARS-CoV-2 during the first pandemic wave had died, 6 (11%) during the initial admission and 14 (25%) in the following months, mainly within the first 3 months after diagnosis. Overall, 30% of patients died from vascular causes and 40% from respiratory causes. In adjusted analysis, a positive SARS-CoV-2 PCR test for diagnosis {hazard ratio [HR] 5.18 [interquartile range (IQR) 1.30-20.65], P = 0.020}, higher baseline C-reactive protein levels [HR 1.10 (IQR 1.03-1.16), P = 0.002] and lower haemoglobin levels [HR 0.62 (IQR 0.45-0.86), P = 0.005] were associated with higher 1-year mortality. Mortality in the 144 patients who did not have COVID-19 was 21 (14.6%) over 12 months [HR of death for COVID-19 patients 3.00 (IQR 1.62-5.53), log-rank P = 0.00023]. Over the first year, the percentage of patients having anti-SARS-CoV-2 immunoglobulin G (IgG) decreased from 36/49 (73.4%) initially to 27/44 (61.3%) at 6 months and 14/36 (38.8%) at 12 months. Conclusions: The high mortality of HD patients with COVID-19 is not limited to the initial hospitalization. Defining COVID-19 deaths as those occurring within 3 months of a COVID-19 diagnosis may better represent the burden of COVID-19. In HD patients, the anti-SARS-CoV-2 IgG response was suboptimal and short-livedThis research received no external funding. The research groups of E.G.-P., S.M. and A.O. are funded by the Ministerio de Economia, Industria y competitividad: FIS/Fondos FEDER (PI16/01298, PI17/00257, PI18/01386, PI19/00588, PI19/00815, PI20/00487, PI21/01430), ERA-PerMed-JTC2018 (KIDNEY ATTACK AC18/00064 and PERSTIGAN AC18/00071, ISCIII-RETIC REDinREN RD016/-0009) and Sociedad Española de Nefrología, Comunidad de Madrid en Biomedicina (B2017/BMD-3686 CIFRA2-CM

The spectrum of clinical and serological features of COVID-19 in urban hemodialysis patients

The inherent immunosuppression of uremia increases the susceptibility of hemodialysis patients to infection. There is still limited evidence on hemodialysis patients and COVID-19. The clinical and analytical spectrum and treatment responses and mortality are poorly characterized. Material and Methods: Clinical and analytical features, chest X-ray, polymerase chain reaction (PCR) and antibodies for SARS-CoV-2, treatment and outcomes were analyzed in 48 patients diagnosed with COVID-19 during March and April 2020 in two coordinated Spanish hemodialysis units. Results: In 200 haemodialysis patients, COVID-19 was diagnosed in 48, of whom 22 were PCR positive, eight PCR negative but seroconverted and two were diagnosed on typical clinical grounds. Despite a mean age of 72.6 years, the overall mortality rate was 5/48 (10%). Among the PCR positive patients, 21 (55%) required admission and five (13%) died. PCR positive patients were more often symptomatic and hospitalized and had higher troponin I levels than PCR negative patients, but did not differ in lymphocyte counts, D-dimer or interleukin-6 (IL-6) levels. Among PCR negative COVID-19 patients, three out of 10 (30%) required admission, and none died. The most frequent symptom among the 48 patients was fever (31%), followed by asymptomatic patients (23%). A low number of lymphocytes was the only parameter significantly different between hospitalized and ambulatory COVID-19 patients, independently of PCR status. Conclusions: COVID-19 hemodialysis patients are frequently asymptomatic, and mortality may be lower than previously reported. Diagnosis may be retrospective, based on seroconversion, as PCR may be negative. This information should guide preventive and patient isolation strategiesResearch support from FIS ISCIII FEDER funds PI16/01298, PI15/00298, PI16/02057, PI16/01900, PI19/00815, DTS18/00032 ISCIII-RETIC REDinREN RD16/0009, CYTED IBERERC and Sociedad Madrileña de Nefrologia, ERA-PerMed-JTC2018 (KIDNEY ATTACK AC18/00064 and PERSTIGAN AC18/00071), Comunidad de Madrid CIFRA2 B2017/BMD-3686. to A

Memorias Simposio Actualización Endocrinología Médicas UIS 2015

“Generando conocimiento más allá de la diabetes