Modular architecture of protein structures and allosteric communications: potential implications for signaling proteins and regulatory linkages

A new method for studying signal transmission between functional sites by decomposing protein structures into modules demonstrates that protein domains consist of modules interconnected by residues that mediate signaling through the shortest pathways

Influence of Dust in Solar Cells Used for Measuring Solar Radiation

Permiso obtenido por la institución para subir este documentoThe photovoltaic cells (PV) are commonly used as global radiation measurement device, even though when it has been proved that there are significant differences with respect to using pyranometers. The dirt deposited on the surface of the PV is one of the most influential factors in the measurement of the solar radiation. In this work we have made experimental measurements with four identical cells, two cleans and two dirties with different soil density (0.2 g/m2, 0.4 g/m2, 0.8 g/m2, 1.2 g/m2 and 1.5 g/m2) and different size particles (< 125 μm) comparing the results and obtaining a correlation between the density of the dust and the difference between the measured irradiance for clean and dirty cells for each particle size

Spanish Dentists’ Awareness, Knowledge, and Practice Regarding COVID-19: A Multiple Regression Analysis

The authors thank the Spanish Society of Epidemiology and Oral Public Health (SESPO) for expert supervision of the questionnaire; the Spanish General Council of Dentists (GCD) and the Spanish societies of dental hygienists for their rapid dissemination of the survey to their members.Introduction: During the first months of the coronavirus disease 2019 (COVID-19) pandemic, Spain had the highest mortality rate and the second-highest infection rate in the world. Objective: To analyze the occupational situation of dentists, hygienists, and dental auxiliary staff during the peak of the pandemic, after the state of alarm was declared in Spain, and when the state of alarm was declared. In addition, a possible relationship between the geographical distribution of infected people and the availability of individual protection systems was investigated. Material and Methods: A cross-sectional questionnaire was answered by 6470 dentists and dental staff via WhatsApp and social media. Results: A total of 1 in 4 dental professionals ceased working completely. Of those that kept working, 25.28% of dentists and 19.61% of hygienist-auxiliary were equipped with filtering face piece (FFP) 2 masks (P < .05), and 61.8% complied with the official protection recommendations set by the General Council of Dentists of Spain. Nearly 59.4% of respondents had symptoms, but only 1.5% of dentists were tested, with 14% of dentists in isolation at the time of response. Overall, it is suggested that 10% of dental professionals may have been in direct contact with the coronavirus. Conclusions: Direct contact of Spanish dental health professionals with severe acute respiratory syndrome coronavirus disease 2 (SARS CoV-2) has been high during the most active phase of the pandemic. Dental professionals did not have personal protective equipment (PPE) necessary to care for patients, a situation that justified the reduction in scheduled dental care and only emergencies being treated. The Spanish geographical regions with the highest number of contagions had the least amount of individual protective resources (FFP2 and FFP3masks)

Fluoxetine: a case history of its discovery and preclinical development

Introduction: Depression is a multifactorial mood disorder with a high prevalence worldwide. Until now, treatments for depression have focused on the inhibition of monoaminergic reuptake sites, which augment the bioavailability of monoamines in the CNS. Advances in drug discovery have widened the therapeutic options with the synthesis of so-called selective serotonin reuptake inhibitors (SSRIs), such as fluoxetine. Areas covered: The aim of this case history is to describe and discuss the pharmacokinetic and pharmacodynamic profiles of fluoxetine, including its acute effects and the adaptive changes induced after long-term treatment. Furthermore, the authors review the effect of fluoxetine on neuroplasticity and adult neurogenesis. In addition, the article summarises the preclinical behavioural data available on fluoxetine’s effects on depressive-like behaviour, anxiety and cognition as well as its effects on other diseases. Finally, the article describes the seminal studies validating the antidepressant effects of fluoxetine. Expert opinion: Fluoxetine is the first selective SSRI that has a recognised clinical efficacy and safety profile. Since its discovery, other molecules that mimic its mechanism of action have been developed, commencing a new age in the treatment of depression. Fluoxetine has also demonstrated utility in the treatment of other disorders for which its prescription has now been approved

Assessment of a Global-to-Direct empirical model for the long-term characterization of Direct Normal Insolation

The statistical characterization of the solar resource (direct normal solar radiation) is a key point in the initial phases of a solar thermal electricity (STE) plant project. Ideally, this characterization should be based on long time series (at least 8 years) of on-site measured data of Direct Normal Insolation (DNI) and other meteorological parameters. Unfortunately, there are very few places around the world where such time series are available, so alternative methods have to be used. Most of them rely on the application of global-to-direct conversion models to long time series of Global Horizontal Insolation (GHI), measured or derived from satellite images, to estimate the long-term resource. Usually, a meteorological station including sensors for the measurement of DNI is installed at the selected project site at the beginning of the project. The data collected during the measurement campaign, which normally extends between a few months and 2 years, are used to adjust the conversion models and to correct the estimates. In this paper, a simple empirical model that relates monthly clearness index and monthly direct normal fraction is used to estimate monthly and annual long-term DNI from statistically representative monthly values of GHI. This model is adjusted with GHI and DNI data collected during measurement campaigns of different durations. We show that the accuracy of the proposed model is under +-5% and that this accuracy improves sharply with the duration of the test campaign. For this purpose, we have used 13 years of high quality DNI and GHI data from the radiometric station of the Group of Thermodynamics and Renewable Energies (GTER) of the University of Seville, Spain. The results suggest that, this simple empirical model is a good alternative to the present methodologies when short DNI measurement campaign but long-term GHI values are available

Analysis of the distribution of measured and synthetic DNI databases and its effect on the expected production of a parabolic trough plan

The generation of a Typical Meteorological Year (TMY) is a common practice in solar energy projects. Therefore it is desirable that the TMY provides not only a good estimate of the solar resource in the long term, but also an adequate input for the estimation of the performance of the project during its lifetime. The main goal of this work is to analyze and compare the effect of using synthetic and measured time series on the statistical relationships between the annual Direct Normal Insolation (DNI) values and the corresponding electricity generation of a Solar Thermal Electricity (STE) plant. For this purpose we have used two DNI databases: (a) terrestrial database with thirteen years (2000 to 2012) of 5-second measurements for the location of Seville, Spain, and (b) synthetic database generated with the Meteonorm® V 6.1.0.23 software, by applying GHI-DNI conversion models to the measured monthly values of GHI for the same location. We have used the EOS code to estimate the electricity generation of a 50 MW parabolic trough plant with 8 equivalent hours of thermal energy storage (TES) capacity. The results show that the use of synthetic series introduces an additional uncertainty that has to be analyzed for each project, being in this study the differences between the measured and synthetic data around a 2-3% for the annual values and for the main statistical parameters

Mathematical models for COVID-19 Infection estimation: Essential considerations and projections in Colombia

Objetivo Estimar el comportamiento de la infección por COVID-19 en Colombia mediante modelos matemáticos. Métodos Se construyeron dos modelos matemáticos para estimar los casos confirmados importados y los casos confirmados relacionados de la infección por COVID-19 en Colombia, respectivamente. La fenomenología de los casos confirmados importados es modelada con una función sigmoidal, mientras que los casos confirmados relacionados son modelados mediante una combinación de funciones exponenciales y funciones algebraicas polinomiales. Se utilizan algoritmos de ajuste basados en métodos de mínimos cuadrados y métodos de búsqueda directa para la determinación de los parámetros de los modelos. Resultados El modelo sigmodial realiza una estimación altamente convergente de los datos reportados, al 28 de mayo de 2020, de los casos confirmados importados de infección por COVID-19. El modelo muestra un error de predicción de 0,5%, que se mide usando la raíz del error cuadrático medio normalizado. El modelo para los casos confirmados reportados como relacionados muestra un error en la predicción del 3,5 % y un sesgo bajo del -0,01 asociado a la sobrestimación. Conclusiones El presente trabajo evidencia que los modelos matemáticos permiten eficaz y efectivamente predecir el comportamiento de la infección por COVID-19 en Colombia cuando los casos importados y los casos relacionados de infección son consideradores de manera independiente

Modelos para la datación de hierros y aceros antiguos aplicados a Tizona

This article deals with the study of the assessment of the natural aging of archaeological pieces, as a dating model for ancient pieces of iron and steels. As introduction of the article, it also shows other three methods. The first one is radiocarbon dating. The other ones are based on the diffusion of some elements by means of the corrosion layer and the slags. The method, which has been researched, has been applied to the specific issue of the sword Tizona. It propounds a mathematical method, which allow us to verify its age. Optic Microscopy and Scanning Electron Microscopy (SEM), both low and high resolution, are techniques used to carry out this study.El presente artículo trata sobre el estudio de la valoración del envejecimiento natural de piezas arqueológicas, como modelo para la datación de piezas de hierro y acero antiguas. También se indican otros tres métodos a modo de introducción, uno es del Carbono 14, y los otros se basan en la difusión de elementos a través de la capa de corrosión y a través de escorias. El método estudiado se ha aplicado al caso concreto de la espada Tizona proponiendo un método matemático que nos permite averiguar su antigüedad. Para este estudio nos hemos ayudado de técnicas como la Microscopía Óptica y Microscopía Electrónica de Barrido (MEB), tanto de baja como de alta resolución

Instantaneous current vectors in polyphase systems: two compensation concepts

6 páginas, 9 figuras, 24 referencias.-- Trabajo presentado al Modern Electric Power Systems (MEPS) International Symposium, celebrado del 20-22 de septiembre 2010, en Wroclaw, Polonia.According to the target of minimal line losses and a power factor equal to one, the present work studies two concepts of instantaneous compensation of nonactive current which are generally applied to polyphase systems. The analysis is defined both on the basis of the instantaneous value concept, for arbitrary voltage and current waveforms, and on the basis of the average value concept, for steady-state and periodic conditions. Results of using these concepts for instantaneous compensation are compared by simulation.Peer reviewe

Updating the distribution of Dicrodon guttulatum Duméril & Bibron, 1839 (Reptilia, Teiidae) with a disjunct population in the eastern slope of the Peruvian Andes

We report a disjunct population of Dicrodon guttulatum Duméril & Bibron, 1839 on the eastern slope of the Cordillera Occidental in the inter-Andean Seasonally Dry Forests of the Marañón River, in the Departments of Cajamarca and Piura in northwestern Peru. We include an updated range distribution map using records from museum specimens, the Global Biodiversity Information Facility, and available photographic records on iNaturalist. In addition, we identify widespread cultivation of rice crops as the main threat to D. guttulatum in the inter-Andean Seasonally Dry Forests of the Marañón