A combination of transcriptional and microRNA regulation improves the stability of the relative concentrations of target genes

It is well known that, under suitable conditions, microRNAs are able to fine tune the relative concentration of their targets to any desired value. We show that this function is particularly effective when one of the targets is a Transcription Factor (TF) which regulates the other targets. This combination defines a new class of feed-forward loops (FFLs) in which the microRNA plays the role of master regulator. Using both deterministic and stochastic equations we show that these FFLs are indeed able not only to fine-tune the TF/target ratio to any desired value as a function of the miRNA concentration but also, thanks to the peculiar topology of the circuit, to ensures the stability of this ratio against stochastic fluctuations. These two effects are due to the interplay between the direct transcriptional regulation and the indirect TF/Target interaction due to competition of TF and target for miRNA binding (the so called "sponge effect"). We then perform a genome wide search of these FFLs in the human regulatory network and show that they are characterizedby a very peculiar enrichment pattern. In particular they are strongly enriched in all the situations in which the TF and its target have to be precisely kept at the same concentration notwithstanding the environmental noise. As an example we discuss the FFL involving E2F1 as Transcription Factor, RB1 as target and miR-17 family as master regulator. These FFLs ensure a tight control of the E2F/RB ratio which in turns ensures the stability of the transition from the G0/G1 to the S phase in quiescent cells.Comment: 23 pages, 10 figure

Comparative study of AC and positive and negative DC visual corona for sphere-plane gaps in atmospheric air

Due to the expansion of high-voltage direct current (HVDC) power systems, manufacturers of high-voltage (HV) hardware for alternating current (ac) applications are focusing their efforts towards the HVDC market. Because of the historical preponderance of ac power systems, such manufacturers have a strong background in ac corona but they need to acquire more knowledge about direct current (dc) corona. Due to the complex nature of corona, experimental data is required to describe its behavior. This work performs an experimental comparative analysis between the inception of ac corona and positive and negative dc corona. First, the sphere-plane air gap is analyzed from experimental data, and the corona inception voltages for different geometries are measured in a high-voltage laboratory. Next, the surface electric field strength is determined from finite element method simulations, since it provides valuable information about corona inception conditions. The experimental data obtained are fitted to an equation based on Peek’slaw,whichallows determining the equivalence between the visual corona surface electric field strength for ac and dc supply. Finally, additional experimental results performed on substation connectors are presented to further validate the previous results by means of commercial high-voltage hardware. The results presented in this paper could be especially valuable for high-voltage hardware manufacturers, since they allow determining the dc voltage and electric field values at which their ac products can withstand free of corona when operating in dc grids.Peer ReviewedPostprint (published version

La legitimación del concubino para solicitar resarcimiento por daños y perjuicios

Ningun

Anthropization and growth of the electricity grid as variables for the analysis of urban infrastructure

City growth goes together with the development of infrastructure, and the power network is one of the most relevant towards economic development. The study of urban infrastructure through the analysis of anthropization coupled with power network growth can produce a tool that supports sustainable infrastructure planning, both economic and environmental. The case study focuses on Ambato, Ecuador, in the period from 1950 to 2019, and assesses quantitatively the changes in the city layout and the evolution of its power network. The data are adjusted to a sigmoid-type objective function through a non-linear least squares problem, that is solved using the Broyden–Fletcher–Goldfarb–Shanno (BFGS) method. Anthropization data show how the urban area grew during the study period: 37% (1950–1960), 53% (1960–1970), 80% (1970–1980), 35% (1980–1990), 39% (1990–2000), 38% (2000–2010), and 11% (2010–2019), mostly at the expense of agricultural land. The forecast for new power network users by 2050 yields a result of 203,630 total users with a population density of 4850 people/km2. The conclusion is that this type of analysis can help city planners and decision makers further understand city and infrastructure growth dynamics and produce policies that bolster sustainable city growth.Peer ReviewedPostprint (published version

N-glycome profile levels relate to silent brain infarcts in a cohort of hypertensives

Background: Silent brain infarcts (SBIs) are highly prevalent in the aged population and relate to the occurrence of further stroke and dementia. Serum N-glycome levels have been previously associated with aging and they might be related as well to the presence of SBIs and age-related white matter hyperintensities. Methods and Results: We determined the serum N-glycome profile in a cohort study comprising 972 subjects and evaluated the relationship between N-glycome levels and the presence and number of SBIs and with age-related white matter hyperintensities grades, assessed by brain magnetic resonance imaging. Decreasing concentrations of bigalacto core-alpha-1,6-fucosylated biantennary glycan and increasing concentrations of branching alpha-1,3-fucosylated triantennary glycan remained as independent predictors of SBIs (odds ratio 0.4, 95% CI 0.3-0.7 and odds ratio 1.8, 95% CI 1-3.2, respectively), after controlling for the presence of age and classic vascular risk factors. A similar pattern was found to be related to an increasing number of SBIs and white matter hyperintensities grade. Conclusions: N-glycome levels might be potentially useful as biomarkers for the presence of silent cerebrovascular disease

Delirium superpuesto a demencia: revisión de una entidad clínica subdiagnosticada

  Both delirium and dementia are frequent pathologies globally, in both cases the prevalence increases as people age, therefore, taking into account the current population trend towards ageing, the study of these clinical entities has become more relevant. In this article, the key points of delirium and the types of dementia are remembered, and at last what has been published up to date about these two entities together is presented, as well as the challenges that will be faced in the future on this topic.            Tanto el delirium como la demencia son patologías frecuentes a nivel mundial, ambas presentan una mayor prevalencia conforme aumenta la edad; por ello, con la actual tendencia poblacional al envejecimiento, el estudio de estas entidades clínicas ha tomado cada vez mayor relevancia. En este artículo se recuerdan los puntos clave del delirium, los tipos de demencia y, finalmente, se presenta una revisión de lo que se ha publicado en la literatura hasta el momento sobre estas dos entidades en conjunto, así como los retos a futuro en este tema

Invasive pulmonary aspergillosis in heart transplant recipients: Is mortality decreasing

Introduction: Infection remains a major complication among heart transplant (HT) recipients, causing approximately 20% of deaths in the first year after transplantation. In this population, Aspergillus spp. can have various clinical presentations including invasive pulmonary aspergillosis (IPA), with high mortality (53-78%). Objectives: To establish the characteristics of IPA infection in HT recipients and their outcomes in our center. Methods: Among 328 HTs performed in our center between 1998 and 2016, we identified five cases of IPA. Patient medical records were examined and clinical variables were extracted. Results: All cases were male, and mean age was 62 years. The most common indication for HT was non-ischemic dilated cardiomyopathy. Productive cough was reported as the main symptom. The radiological assessment was based on chest X-ray and chest computed tomography. The most commonly reported radiographic abnormality was multiple nodular opacities in both techniques. Bronchoscopy was performed in all patients and Aspergillus fumigatus was isolated in four cases on bronchoalveolar lavage culture. Treatment included amphotericin in four patients, subsequently changed to voriconazole in three, and posaconazole in one patient, with total treatment lasting an average of 12 months. Neutropenia was found in only one patient, renal failure was observed in two patients, and concurrent cytomegalovirus infection in three patients. All patients were alive after a mean follow-up of 18 months. Conclusions: IPA is a potentially lethal complication after HT. Early diagnosis and prompt initiation of aggressive treatment are the cornerstone of better survival

The plant tissue culture collection at the Department of Botany, University of Debrecen

K

Tendencias en la jurisprudencia de la Justicia Municipal de Faltas de la ciudad de Córdoba

El proyecto consiste en la identificación de las tendencias jurisprudenciales que con relación al ejercicio de las principales cuestiones referidas al poder de policía municipal surgen de los fallos de la Cámara Administrativa Municipal de Faltas de la Ciudad de Córdoba y su análisis a la luz de la doctrina, legislación y jurisprudencia local, nacional e internacional en la materia.Fil: Mayor, Armando Gualberto. Universidad Católica de Córdoba. Facultad de Derecho y Ciencias Sociales; ArgentinaFil: Calderón, Maximiliano Rafael. Universidad Católica de Córdoba. Facultad de Derecho y Ciencias Sociales; Argentin