Trend in statistical research productivity by journal publications over the period 1985-1997

This work presents a descriptive analysis of the dynamic evolution of statistical research productivity over the period 1985-1997. Research productivity is measured by using the volume of articles published in a set of journals with high impact index. We analyze the productivity trends in the thirty most productive countries and in the twenty top institutions of United States, Europe and the rest of the world

Constraints on stellar convection from multi-colour photometry of Delta Scuti stars

In Delta Scuti star models, the calculated amplitude ratios and phase differences for multi-colour photometry exhibit a strong dependence on convection. These observables are tools for determination of the spherical harmonic degree of the excited modes. The dependence on convection enters through the complex parameter f, which describes bolometric flux perturbation. We present a method of simultaneous determination of f and spherical harmonic degree from multi-colour data and apply it to three Delta Scuti stars. The method indeed works. Determination of the degree appears unique and the inferred f's are sufficiently accurate to yield a useful constraint on models of stellar convection. Furthermore, the method helps to refine stellar parameters, especially if the identified mode is radial.Comment: 9 pages, 12 figures, to appear in Astronomy and Astrophysic

A Graph Approach to Observability in Physical Sparse Linear Systems

A sparse linear system constitutes a valid model for a broad range of physical systems, such as electric power networks, industrial processes, control systems or traffic models. The physical magnitudes in those systems may be directly measured by means of sensor networks that, in conjunction with data obtained from contextual and boundary constraints, allow the estimation of the state of the systems. The term observability refers to the capability of estimating the state variables of a system based on the available information. In the case of linear systems, diffierent graphical approaches were developed to address this issue. In this paper a new unified graph based technique is proposed in order to determine the observability of a sparse linear physical system or, at least, a system that can be linearized after a first order derivative, using a given sensor set. A network associated to a linear equation system is introduced, which allows addressing and solving three related problems: the characterization of those cases for which algebraic and topological observability analysis return contradictory results; the characterization of a necessary and sufficient condition for topological observability; the determination of the maximum observable subsystem in case of unobservability. Two examples illustrate the developed techniques

Techno-economic evaluation of a grid-connected hybrid PV-wind power generation system in San Luis Potosi, Mexico

This paper presents a study of the installation of a hybrid PV-Wind power generation system for social interest houses in the city of San Luis Potosi, Mexico. To assess the benefits of the implementation of this type of systems, a technological, economic and environmental evaluation is carried out based on the available renewable energy resources and considering a typical load profile of consumers. The obtained results show the feasibility of installation of small capacity hybrid generation systems in the city, however governmental incentives must be implemented to make more attractive and affordable the proposed systems for medium/low income users

A low-mass planet candidate orbiting Proxima Centauri at a distance of 1.5 AU

Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).Our nearest neighbor, Proxima Centauri, hosts a temperate terrestrial planet. We detected in radial velocities evidence of a possible second planet with minimum mass m c sin i c = 5.8 ± 1.9 M ⊕ and orbital period P c = 5.21 - 0.22 + 0.26 years. The analysis of photometric data and spectro-scopic activity diagnostics does not explain the signal in terms of a stellar activity cycle, but follow-up is required in the coming years for confirming its planetary origin. We show that the existence of the planet can be ascertained, and its true mass can be determined with high accuracy, by combining Gaia astrometry and radial velocities. Proxima c could become a prime target for follow-up and characterization with next-generation direct imaging instrumentation due to the large maximum angular separation of ~1 arc second from the parent star. The candidate planet represents a challenge for the models of super-Earth formation and evolution.Peer reviewedFinal Published versio

HPV-16 infection modifies overall survival of Puerto Rican HNSCC patients

International audienceThis paper presents a set of experimental results concerning the sliding mode control of an electro-pneumatic system. Two discrete-time control strategies are considered for the implementation of the discontinuous part of the sliding mode controller: explicit and implicit discretizations. While the explicit implementation is known to generate numerical chattering [6], [7], [12], [13], the implicit one is expected to significantly reduce chattering while keeping the accuracy. The experimental results reported in this work remarkably confirm that the implicit discrete-time sliding mode supersedes the explicit ones, with several important features: chattering in the control input is almost eliminated (while the explicit and saturated controllers behave like high-frequency bang-bang inputs), the input magnitude depends only on the perturbation size and is largely independent of the controller gain and sampling time

Effect of Co-Inoculation with Mycorrhiza and Rhizobia on the Nodule Trehalose Content of Different Bean Genotypes

Studies on Rhizobium-legume symbiosis show that trehalose content in nodules under drought stress correlates positively with an increase in plant tolerance to this stress. Fewer reports describe trehalose accumulation in mycorrhiza where, in contrast with rhizobia, there is no flux of carbohydrates from the microsymbiont to the plant. However, the trehalose dynamics in the Mycorrhiza-Rhizobium-Legume tripartite symbiosis is unknown. The present study explores the role of this tripartite symbiosis in the trehalose content of nodules grown under contrasting moisture conditions. Three wild genotypes (P. filiformis, P. acutifolis and P. vulgaris) and two commercial genotypes of Phaseolus vulgaris (Pinto villa and Flor de Mayo) were used. Co-inoculation treatments were conducted with Glomus intraradices and a mixture of seven native rhizobial strains, and trehalose content was determined by GC/MS. The results showed a negative effect of mycorrhizal inoculation on nodule development, as mycorrhized plants showed fewer nodules and lower nodule dry weight compared to plants inoculated only with Rhizobium. Mycorrhizal colonization was also higher in plants inoculated only with Glomus as compared to plants co-inoculated with both microsymbionts. In regard to trehalose, co-inoculation negatively affects its accumulation in the nodules of each genotype tested. However, the correlation analysis showed a significantly positive correlation between mycorrhizal colonization and nodule trehalose content

Exposure assessment of severe acute respiratory syndrome coronavirus 2 and norovirus genogroup I/genogroup II in aerosols generated by a municipal wastewater treatment plant

The presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in wastewater and its potential as an airborne transmission source require extensive investigation, particularly in wastewater treatment plants (WWTPs), where few studies have been conducted. The aim of this study was to investigate the presence of SARS-CoV-2 and norovirus (NoV) RNA in wastewater and air samples collected from a municipal WWTP. In addition, the study assessed the potential risk of viral exposure among WWTP employees. In both the summer and winter campaigns of this study, SARS-CoV-2 and NoV RNA were quantified in wastewater/sludge samples other than effluent. Viral RNA was not detected in any of the air samples collected. The exposure risk assessment with the SARS-CoV-2 RNA concentrations in the influent pumping station of this study shows a lower risk than the calculation with the historical data provided by AquaVall, but both show a low-to-medium exposure risk for the WWTP workers. The sensitivity analysis shows that the result of the model is strongly influenced by the SARS-CoV-2 RNA quantification in the wastewater. This study underscores the need for extensive investigations into the presence and viability of SARS-CoV-2 in wastewater, especially as a potential airborne transmission source within WWTPs. © 2024 The Author(s). CLEAN – Soil, Air, Water published by Wiley-VCH GmbH.This work was funded by the Marie Skłodowska-Curie Actions Postdoctoral Fellowship (project PLASMARISE – 101151154). This work was performed with financial support from the Regional Government of Castilla y León and the FEDER program (Projects CLU 2017-09, CL-EI-2021-07, UIC315, and VA266P20). This work was funded by Fundação para a Ciência e a Tecnologia (FCT, Portugal), through the strategic projects UIDB/04292/2020 (https://doi.org/10.54499/UIDB/04292/2020) and UIDP/04292/2020 (https://doi.org/10.54499/UIDP/04292/2020) granted to MARE—Marine and Environmental Sciences Centre, and the project LA/P/0069/2020 (https://doi.org/10.54499/LA/P/0069/2020) granted to the Associate Laboratory ARNET—Aquatic Research Network. Agua de Valladolid E.P.E.L (AquaVall) is also gratefully acknowledged for providing the samples and preliminary dat

New compound sets identified from high throughput phenotypic screening against three kinetoplastid parasites:an open resource

Using whole-cell phenotypic assays, the GlaxoSmithKline high-throughput screening (HTS) diversity set of 1.8 million compounds was screened against the three kinetoplastids most relevant to human disease, i.e. Leishmania donovani, Trypanosoma cruzi and Trypanosoma brucei. Secondary confirmatory and orthogonal intracellular anti-parasiticidal assays were conducted, and the potential for non-specific cytotoxicity determined. Hit compounds were chemically clustered and triaged for desirable physicochemical properties. The hypothetical biological target space covered by these diversity sets was investigated through bioinformatics methodologies. Consequently, three anti-kinetoplastid chemical boxes of ~200 compounds each were assembled. Functional analyses of these compounds suggest a wide array of potential modes of action against kinetoplastid kinases, proteases and cytochromes as well as potential host–pathogen targets. This is the first published parallel high throughput screening of a pharma compound collection against kinetoplastids. The compound sets are provided as an open resource for future lead discovery programs, and to address important research questions.The support and funding of Tres Cantos Open Lab Foundation is gratefully acknowledgedPeer reviewe