Relationships between PCA and PLS-regression

This work aims at comparing several features of Principal Component Analysis (PCA) and Partial Least Squares Regression (PLSR), as techniques typically utilized for modeling, output prediction, and monitoring of multivariate processes. First, geometric properties of the decomposition induced by PLSR are described in relation to the PCA of the separated input and output data (X-PCA and Y-PCA, respectively). Then, analogies between the models derived with PLSR and YX-PCA (i.e., PCA of the joint input-output variables) are presented; and regarding to process monitoring applications, the specific PLSR and YX-PCA fault detection indices are compared. Numerical examples are used to illustrate the relationships between latent models, output predictive models, and fault detection indices. The three alternative approaches (PLSR, YX-PCA and Y-PCA plus X-PCA) are compared with regard to their use for statistical modeling. In particular, a case study is simulated and the results are used for enhancing the comprehension of the PLSR properties and for evaluating the discriminatory capacity of the fault detection indices based on the PLSR and YX-PCA modeling alternatives. Some recommendations are given in order to choose the more appropriate approach for a specific application: 1) PLSR and YX-PCA have similar capacity for fault detection, but PLSR is recommended for process monitoring because present a better diagnosing capability; 2) PLSR is more reliable for output prediction purposes (e.g., for soft sensor development); and 3) YX-PCA is recommended for the analysis of latent patterns imbedded in datasets.Fil: Godoy, José Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico Para la Industria Química (i); Argentina. Universidad Tecnológica Nacional. Facultad Regional Paraná; ArgentinaFil: Vega, Jorge Ruben. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico Para la Industria Química (i); Argentina. Universidad Tecnologica Nacional; ArgentinaFil: Marchetti, Jacinto Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico Para la Industria Química (i); Argentin

New contributions to non linear process monitoring through kernel partial least squares

The kernel partial least squares (KPLS) method was originally focused on soft-sensor calibration for predicting online quality attributes. In this work, an analysis of the KPLS-based modeling technique and its application to nonlinear process monitoring are presented. To this effect, the measurement decomposition, the development of new specific statistics acting on non-overlapped domains, and the contribution analysis are addressed for purposes of fault detection, diagnosis, and prediction risk assessment. Some practical insights for synthesizing the models are also given, which are related to an appropriate order selection and the adoption of the kernel function parameter. A proper combination of scaled statistics allows the definition of an efficient detection index for monitoring a nonlinear process. The effectiveness of the proposed methods is confirmed by using simulation examples. Keywords: KPLS Modeling, Fault Detection, Fault Diagnosis, Prediction Risk Assessment, Nonlinear Processes.Fil: Vega, Jorge Ruben/ Universidad Tecnològica Nacional. ArgentinaPeer Reviewe

Nivel de conocimiento tributario y su incidencia en la formalización de los microempresarios panaderos de la ciudad de Rioja en el periodo 2017

La investigación estuvo sujeta bajo el titulo: Nivel de conocimiento tributario y su incidencia en la formalización de los microempresarios panaderos de la ciudad de Rioja en el periodo 2017. El presente estudio tuvo como objetivo general explicar como incide el nivel de conocimiento tributario en la formalización de los microempresarios panaderos de la ciudad de Rioja en el periodo 2017. Del mismo se desprende que la hipótesis de investigación: El nivel de conocimiento tributario, incide de manera significativa en la formalización de los microempresarios panaderos de la ciudad de Rioja en el periodo 2017. En cuanto a la metodología, el tipo de investigación fue básica con nivel correlacional y diseño no experimental, mientras que la muestra estuvo compuesta por 15 microempresarios informales. Para obtener la información necesaria en el estudio se empleó un test de conocimiento y un cuestionario. Llegándose a obtener en los resultados, que en lo que respecta al nivel del conocimiento tributario, el 60% de los microempresarios no conoce aspectos importantes pero a la vez necesarios de la parte tributaria, mientras que el 40% si conoce pero solo algunos puntos básicos. Por otro lado la formalización obtuvo una calificación de baja por el 53% de los microempresarios encuestados, mientras que el 27% señaló que es alta y el 20% restante afirmó que se encuentra en un nivel de media. Asimismo se logró evidenciar la incidencia que tiene el nivel de conocimiento tributario en la formalización, pues el valor de Chi-cuadrado fue igual a 0,002, siendo menor al margen de error de 0,05. Al finalizar se llegó a concluir que se acepta la hipótesis de investigación, la misma que señala: El nivel de conocimiento tributario incide de manera significativa en la formalización de los microempresarios panaderos de la ciudad de Rioja en el periodo 2017.The following research title as: Level of tax knowledge and its incidence in the formalization of microbusiness bakers in Rioja city during 2017. The general objective of this study was to explain how the level of tax knowledge affects the formalization of the microbusiness bakers of the city of Rioja in the period 2017. It is clear that the research hypothesis the level of tax knowledge has a significant impact on the formalization of baking microbusiness in the city of Rioja during 2017 period. Regarding the methodology, the type of research was basic with correlational level - causal and non-experimental, while the sample consisted of 15 informal micro entrepreneurs. To obtain the necessary information in the study, a knowledge test and a questionnaire were used. As results regarding to the level of tax knowledge, 60% of microbusiness do not know important and necessary aspects from the tax side, while 40% do know but only some basic points. On the other hand, the formalization obtained a low score by 53% of the microbusiness surveyed, while 27% indicated that it is high and the remaining 20% affirmed that it is at an average level. Likewise, it was possible to show the incidence of the level of tax knowledge in the formalization, since the Chi-square value was equal to 0.002, being less than the margin of error of 0.05. At the end, it was concluded that the research hypothesis is accepted, the same one that states: The level of tax knowledge has a significant impact on the formalization of baking microbusiness in the city of Rioja in 2017 period.TesisAp

Determinantes de los flujos de capital: un enfoque empírico desde la economía del Ecuador

The variability of capital flows is conditioned by external factors, linked to the performance of the economies, but also to internal factors linked to policies to attract foreign capital, so that, during the last decades, the behavior of capital flows capital have become an important element for forecasting the economic performance of countries, which has motivated greater and better efforts to understand its dynamics and identify its main determinants in order to take advantage of its benefits and control its risks in the most effective way possible. The paper aims to identify and analyze the main factors that explain the variations in capital flows in the context of the Ecuadorian economy during the period 1990 - 2020, such determinants, according to the literature, the empirical evidence and available data are gross domestic product, country risk, international reserves, foreign direct investment, exports, and external debt. By estimating a multivariate linear regression model for time series, using the ordinary least squares method, it is determined that gross domestic product, international reserves and foreign direct investment have a positive effect and country risk a negative effect. statistically significant, on capital flows. As is evident, capital flows in Ecuador are determined by endogenous and exogenous factors that promote the entry and, on the other hand, encourage the exit of capital from the economy.La variabilidad de los flujos de capital está condicionada por factores externos, ligados al desempeño de las economías, pero también a factores internos vinculados con las políticas de atracción de capitales externos, por lo que, durante las últimas décadas, los comportamientos de los flujos de capital se han convertido en un elemento importante para pronosticar el desempeño económico de los países, lo cual ha motivado realizar mayores y mejores esfuerzos para comprender su dinámica e identificar sus principales determinantes para aprovechar sus beneficios y controlar sus riesgos de manera más efectiva posible. El artículo tiene como objetivo identificar y analizar los principales factores que explican las variaciones de los flujos de capital en el contexto de la economía ecuatoriana durante el periodo 1990 - 2020, tales determinantes, acorde a la literatura, la evidencia empírica y los datos disponible son el producto interno bruto, el riesgo país, las reservas internacionales, la inversión extranjera directa, las exportaciones y la deuda externa. Mediante la estimación de un modelo de regresión lineal multivariante para series temporales, usando el método de mínimos cuadrados ordinarios, se determina que el producto interno bruto, las reservas internacionales y la inversión extranjera directa tienen un efecto positivo y el riesgo país un efecto negativo, estadísticamente significativos, sobre los flujos de capital. Como es evidente, los flujos de capital en el Ecuador están determinados por factores endógenos y exógenos que promueven la entrada y, por otro lado, fomentan la salida de los capitales de la economía

Predicting the effects of climate change on future freshwater fish diversity at global scale

The aim of the present study was to predict future changes in biodiversity attributes (richness, rarity, heterogeneity, evenness, functional diversity and taxonomic diversity) of freshwater fish species in river basins around the world, under different climate scenarios. To do this, we use a new methodological approach implemented within the ModestR software (NOO3D) which allows estimating simple species distribution predictions for future climatic scenarios. Data from 16,825 freshwater fish species were used, representing a total of 1,464,232 occurrence records. WorldClim 1.4 variables representing average climate variables for the 1960¿1990 period, together with elevation measurements, were used as predictors in these distribution models, as well as in the selection of the most important variables that account for species distribution changes in two scenarios (Representative Concentration Pathways 4.5 and 6.0). The predictions produced suggest the extinction of almost half of current freshwater fish species in the coming decades, with a pronounced decline in tropical regions and a greater extinction likelihood for species with smaller body size and/or limited geographical ranges.We acknowledge institutional support from the Unit of Information Resources for Research at the Unit of Information Resources for Research at the "Consejo Superior de Investigaciones Científicas" (CSIC) for the article-processing charges contribution

A procedure to assess the spatial variability in the importance of abiotic factors affecting distributions: the case of world freshwater fishes

Understanding the factors shaping species' distributions is a key longstanding topic in ecology with unresolved issues. The aims were to test whether the relative contribution of abiotic factors that set the geographical range of freshwater fish species may vary spatially and/or may depend on the geographical extent that is being considered. The relative contribution of factors, to discriminate between the conditions prevailing in the area where the species is present and those existing in the considered extent, was estimated with the instability index included in the R package SPEDInstabR. We used 3 different extent sizes: 1) each river basin where the species is present (local); 2) all river basins where the species is present (regional); and 3) the whole Earth (global). We used a data set of 16,543 freshwater fish species with a total of 845,764 geographical records, together with bioclimatic and topographic variables. Factors associated with temperature and altitude show the highest relative contribution to explain the distribution of freshwater fishes at the smaller considered extent. Altitude and a mix of factors associated with temperature and precipitation were more important when using the regional extent. Factors associated with precipitation show the highest contribution when using the global extent. There was also spatial variability in the importance of factors, both between species and within species and from region to region. Factors associated with precipitation show a clear latitudinal trend of decreasing in importance toward the equator

Comparative and functional genomics of the protozoan parasite Babesia divergens highlighting the invasion and egress processes

Babesiosis is considered an emerging disease because its incidence has significantly increased in the last 30 years, providing evidence of the expanding range of this rare but potentially life-threatening zoonotic disease. Babesia divergens is a causative agent of babesiosis in humans and cattle in Europe. The recently sequenced genome of B. divergens revealed over 3,741 protein coding-genes and the 10.7-Mb high-quality draft become the first reference tool to study the genome structure of B. divergens. Now, by exploiting this sequence data and using new computational tools and assembly strategies, we have significantly improved the quality of the B. divergens genome. The new assembly shows better continuity and has a higher correspondence to B. bovis chromosomes. Moreover, we present a differential expression analysis using RNA sequencing of the two different stages of the asexual lifecycle of B. divergens: the free merozoite capable of invading erythrocytes and the intraerythrocytic parasite stage that remains within the erythrocyte until egress. Comparison of mRNA levels of both stages identified 1,441 differentially expressed genes. From these, around half were upregulated and the other half downregulated in the intraerythrocytic stage. Orthogonal validation by real-time quantitative reverse transcription PCR confirmed the differential expression. A moderately increased expression level of genes, putatively involved in the invasion and egress processes, were revealed in the intraerythrocytic stage compared with the free merozoite. On the basis of these results and in the absence of molecular models of invasion and egress for B. divergens, we have proposed the identified genes as putative molecular players in the invasion and egress processes. Our results contribute to an understanding of key parasitic strategies and pathogenesis and could be a valuable genomic resource to exploit for the design of diagnostic methods, drugs and vaccines to improve the control of babesiosis.This work was funded by grants from Ministerio de Economía y Competitividad from Spain (AGL2010-21774 and AGL2014-56193 R to EM and LMG). ES was awarded a research fellowship from Plan Estatal de Investigación Científica y Técnica y de Innovación, Ministerio de Economía y Competitividad, Spain (http://www.mineco.gob.es/portal/site/mineco/). Work in CL’s laboratory is funded by a grant from the National Institutes of Health (https://www.nih.gov/) NIH- 1R01HL140625-01. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscriptS

Ultrafast photochemistry produces superbright short-wave infrared dots for low-dose in vivo imaging

12 p.-5 fig.Optical probes operating in the second near-infrared window (NIR-II, 1,000-1,700 nm), where tissues are highly transparent, have expanded the applicability of fluorescence in the biomedical field. NIR-II fluorescence enables deep-tissue imaging with micrometric resolution in animal models, but is limited by the low brightness of NIR-II probes, which prevents imaging at low excitation intensities and fluorophore concentrations. Here, we present a new generation of probes (Ag2S superdots) derived from chemically synthesized Ag2S dots, on which a protective shell is grown by femtosecond laser irradiation. This shell reduces the structural defects, causing an 80-fold enhancement of the quantum yield. PEGylated Ag2S superdots enable deep-tissue in vivo imaging at low excitation intensities (<10 mW cm-2) and doses (<0.5 mg kg-1), emerging as unrivaled contrast agents for NIR-II preclinical bioimaging. These results establish an approach for developing superbright NIR-II contrast agents based on the synergy between chemical synthesis and ultrafast laser processing.Authors thank Dr A. Benayas (CICECO, U. Aveiro, Portugal), Prof G. Lifante and Prof J. García Sole (UAM) for helpful discussions. This work has been founded by Ministerio de Economı́a y Competitividad-MINECO (MAT2017-83111R and MAT2016-75362-C3-1-R) and the Comunidad de Madrid (B2017/BMD-3867 RENIM-CM) co-financed by European Structural and Investment Fund. D.M.-G. thanks UCM-Santander for a predoctoral contract (CT17/17-CT18/17). We thank the staff at the ICTS-National Centre for Electron Microscopy at the UCM for the help in the electron microscopy studies and C.M. at the beamline BL22-CLAESS of the Spanish synchrotron ALBA for his help in the XANES experiments. We also thank J.G.I at the Ultrafast Laser Laboratory at UCM for his help and fruitful discussion. Y.S. acknowledges the support from the China Scholarship Council (CSC File No. 201806870023). Additional funding was provided by the European Commission Horizon 2020 project NanoTBTech, the Fundación para la Investigación Biomédica del Hospital Universitario Ramón y Cajal project IMP18_38 (2018/0265). Ajoy K. Kar and Mark D. Mackenzie acknowledge support from the UK Engineering and Physical Sciences Research Council (Project CHAMP, EP/M015130/1). C. Jacinto thanks the financial support of the Brazilian agencies: CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico) through the grants: Projeto Universal Nr. 431736/2018-9 and Scholarship in Research Productivity 1C under the Nr. 304967/20181; FINEP (Financiadora de Estudos e Projetos) through the grants INFRAPESQ-11 and INFRAPESQ-12; FAPEAL (Fundação de Amparo à Pesquisa do Estado de Alagoas) grant Nr. 1209/2016. H. D. A. Santos was supported by a graduate studentship from CNPq and by a sandwich doctoral program (PDSE-CAPES) developed at Universidad Autonoma de Madrid, Spain, Project Nr. 88881/2016-01.Peer reviewe

5to. Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad. Memoria académica

El V Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad, CITIS 2019, realizado del 6 al 8 de febrero de 2019 y organizado por la Universidad Politécnica Salesiana, ofreció a la comunidad académica nacional e internacional una plataforma de comunicación unificada, dirigida a cubrir los problemas teóricos y prácticos de mayor impacto en la sociedad moderna desde la ingeniería. En esta edición, dedicada a los 25 años de vida de la UPS, los ejes temáticos estuvieron relacionados con la aplicación de la ciencia, el desarrollo tecnológico y la innovación en cinco pilares fundamentales de nuestra sociedad: la industria, la movilidad, la sostenibilidad ambiental, la información y las telecomunicaciones. El comité científico estuvo conformado formado por 48 investigadores procedentes de diez países: España, Reino Unido, Italia, Bélgica, México, Venezuela, Colombia, Brasil, Estados Unidos y Ecuador. Fueron recibidas un centenar de contribuciones, de las cuales 39 fueron aprobadas en forma de ponencias y 15 en formato poster. Estas contribuciones fueron presentadas de forma oral ante toda la comunidad académica que se dio cita en el Congreso, quienes desde el aula magna, el auditorio y la sala de usos múltiples de la Universidad Politécnica Salesiana, cumplieron respetuosamente la responsabilidad de representar a toda la sociedad en la revisión, aceptación y validación del conocimiento nuevo que fue presentado en cada exposición por los investigadores. Paralelo a las sesiones técnicas, el Congreso contó con espacios de presentación de posters científicos y cinco workshops en temáticas de vanguardia que cautivaron la atención de nuestros docentes y estudiantes. También en el marco del evento se impartieron un total de ocho conferencias magistrales en temas tan actuales como la gestión del conocimiento en la universidad-ecosistema, los retos y oportunidades de la industria 4.0, los avances de la investigación básica y aplicada en mecatrónica para el estudio de robots de nueva generación, la optimización en ingeniería con técnicas multi-objetivo, el desarrollo de las redes avanzadas en Latinoamérica y los mundos, la contaminación del aire debido al tránsito vehicular, el radón y los riesgos que representa este gas radiactivo para la salud humana, entre otros