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The journal Energies retracts the article “Investigation and Evaluation of the Hybrid System of Energy Storage for Renewable Energies” [...]

El objetivo del estudio es comprobar la efectividad una guía teórico-práctica como objeto de aprendizaje para entornos virtuales en la realización de Proyectos de Investigación (PI) como objeto de aprendizaje para entornos virtuales en el curso de Metodología de Investigación de la Facultad de Educación de una universidad de Lima Metropolitana del Perú. La investigación se fundamenta en los estudios de Gómez et al. (2020), Hernández-Sampieri y Mendoza (2018), Pástor et al. (2020), Peiris et al. (2018), Pérez-Fuentes (2019), Pilozo-Cedeño (2016) entre otros. La investigación cuenta con un diseño cuasiexperimental. La población la constituyen 358 estudiantes y las unidades de estudio fueron noventa estudiantes correspondientes al curso referido de las secciones: 421 y 422. El estudio de la realización de los PI se desarrolla con las dimensiones contextualización del problema, fundamentación teórica y metodología. Las variaciones en la constitución de las dimensiones con sus respectivos indicadores, después de la aplicación de la guía diseñada, probándose en gran medida discrepancias entre estos, debido a que, el estadístico de t computarizado se encuentra relacionado, a valores de significancia inferiores a 0,01. Por ello, se plantea la guía teórica-práctica como objeto de aprendizaje para entornos virtuales como base para la realización de los PI, puesto que dicha guía; optimiza el conocimiento de lo que se va a realizar, optimiza la comunicación, fomenta la motivación, permite un mejor provecho de los recursos, manifiesta la visión y misión de los estudiantes y ha logrado significativos avances en el desarrollo de los proyectos de investigación de los educandos del curso referido.

The purpose of this study was to eliminate phosphate (P) from wastewater using MnFe2O4 nanoparticles. BET, TGA/DTG, FTIR, SEM, TEM, VSM, XRD and EDX/Map analyses were used to determine the MnFe2O4 surface properties. The specific surface area of the adsorbent was 196.56 m2/g and VSM analysis showed that the adsorbent has a ferromagnetic property. The maximum P sorption efficiency using MnFe2O4 (98.52%) was achieved at pH 6, temperature of 55 °C, P concentration of 10 mg/L, time of 60 min, and sorbent dosage of 2.5 g/L, which is a significant value. Also, the thermodynamic study indicated that the P sorption process is spontaneous and endothermic. Moreover, the utmost sorption capacity of P using MnFe2O4 was 39.48 mg/g. Besides, MnFe2O4 can be used for up to 6 reuse cycles with high sorption efficiency (>91%). Also, MnFe2O4 was able to remove phosphate, COD, and BOD5 from municipal wastewater with considerable removal efficiencies of 82.7%, 75.8%, and 77.3%, respectively.

In this study, an eco-friendly procedure was established by vortex-assisted liquid-phase microextraction based on deep eutectic solvent (VA−LPME−DES) combined with graphite furnace atomic absorption spectroscopy (GFAAS). The performance of this method was demonstrated by the extraction and analysis of lead (Pb), cadmium (Cd), and mercury (Hg) in fish samples. The hydrophobic DES is considered as a green extractant (environmentally friendly and less toxic than common organic solvents) and is a suitable alternative to common toxic organic solvents and is made of l-menthol and ethylene glycol (EG) with a molar ratio of 1:1. Under optimized conditions, the method linearity was in the ranges of 0.15–150 µg kg−1 with the coefficient of determinations (r2) higher than 0.996. Accordingly, the detection limits for Pb, Cd, and Hg were 0.05, 0.05, and 0.10 µg kg−1, respectively. The analysis of fish samples showed that the concentration of toxic elements in fish caught from the Tigris and Euphrates Rivers is much higher than the concentration of these elements in locally farmed trout fish. Also, the analysis of fish-certified reference materials with presented procedure produced results that were in good agreement with the certified values. The results showed that VA−LPME–DES is a very cheap, fast, and environmental-friendly procedure for the analysis of toxic elements in different types of fish species.

The genome sequencing revolution has revealed that all species possess a large number of unique genes critical for trait variation, adaptation, and evolutionary innovation. One widely used approach to identify such genes consists of detecting protein‐coding sequences with no homology in other genomes, termed orphan genes. These genes have been extensively studied, under the assumption that they represent valid proxies for species‐specific genes. Here, we critically evaluate taxonomic, phylogenetic, and sequence evolution evidence showing that orphan genes belong to a range of evolutionary ages and thus cannot be assigned to a single lineage. Furthermore, we show that the processes generating orphan genes are substantially more diverse than generally thought and include horizontal gene transfer, transposable element domestication, and overprinting. Thus, orphan genes represent a heterogeneous collection of genes rather than a single biological entity, making them unsuitable as a subject for meaningful investigation of gene evolution and phenotypic innovation. [ABSTRACT FROM AUTHOR]

El emprendimiento puede definirse como la ejecución de un proyecto o propósito donde la persona se encuentra totalmente preparada para arriesgarse y efectuar el proyecto. En el Perú, el emprendimiento empresarial es altamente reconocido, a nivel de América Latina, es el primer país con mayor percepción, en relación con la simplicidad a la hora de dar comienzo a un negocio; y el tercero respecto a las facultades y competencias, así como con mayores posibilidades para que el ciudadano pueda emprender. Este estudio determina la relación entre el perfil emprendedor y la visión emprendedora de estudiantes universitarios. La investigación se desarrolla bajo un enfoque cuantitativo con alcance descriptivo correlacional, la muestra estuvo representada por 135 estudiantes matriculados en la facultad de ciencias de la empresa del Programa de Estudio Administración y Recursos Humanos de la Universidad Continental en el ciclo académico 2022-2022. Se obtuvo un coeficiente de correlación de Pearson de 0,78 lo que indica que existe una correlación positiva entre las variables del estudio, como el perfil emprendedor y la visión emprendedora de estudiantes universitarios. Esto comprueba la hipótesis de investigación: el perfil emprendedor tiene una correspondencia positiva con la visión emprendedora de estudiantes de la facultad de ciencias de la empresa del Programa de Estudio Administración y Recursos Humanos de la Universidad Continental en el ciclo académico 2022-2022.

The system presented in this paper can change the energy storage landscape by having the advantages of a compressed air storage system and pump storage, as well as minimizing the disadvantages of these two systems. One of the advantages of this system compared to similar systems is the lack of combustion of natural gas. Correspondingly, for construction, it does not require specific specifications for the executive site, and control of the energy and heat of the system (due to the use of water as an operational fluid) is easier than similar systems. In addition, this system is very scalable and can be designed in low capacities to high capacities, energy analysis of this research to identify the basic and effective parameters of the system and determine the limitations and relationships between them. The amount of energy saved in the current research system compared to previous research is significant, and 92% efficiency can be achieved. The energy analysis of this research determined the effect of the parameters on each other and their limitations so that the path of its feasibility design was paved.

The objective of the study was to assess the cost of multiple sclerosis (MS) patients in Argentina categorized by disease severity using a societal perspective. Method: Cross-sectional study including MS patients from 21 MS centers in 12 cities of Argentina. Patients were stratified by disease severity using the expanded disability status scale (EDSS) (group 1 with EDSS score between 0 and 3; group 2 with EDSS >3 and 3 and

The above article was published online with incorrect figure 1. [ABSTRACT FROM AUTHOR]

The purpose of this study was to eliminate phosphate (P) from wastewater using MnFe2O4 nanoparticles. BET, TGA/DTG, FTIR, SEM, TEM, VSM, XRD and EDX/Map analyses were used to determine the MnFe2O4 surface properties. The specific surface area of the adsorbent was 196.56 m2/g and VSM analysis showed that the adsorbent has a ferromagnetic property. The maximum P sorption efficiency using MnFe2O4 (98.52%) was achieved at pH 6, temperature of 55 °C, P concentration of 10 mg/L, time of 60 min, and sorbent dosage of 2.5 g/L, which is a significant value. Also, the thermodynamic study indicated that the P sorption process is spontaneous and endothermic. Moreover, the utmost sorption capacity of P using MnFe2O4 was 39.48 mg/g. Besides, MnFe2O4 can be used for up to 6 reuse cycles with high sorption efficiency (>91%). Also, MnFe2O4 was able to remove phosphate, COD, and BOD5 from municipal wastewater with considerable removal efficiencies of 82.7%, 75.8%, and 77.3%, respectively. [ABSTRACT FROM AUTHOR]

Introduction: The discontinuation of disease-modifying therapies (DMTs) in multiple sclerosis (MS) is commonly seen in real-world settings due to several factors., Area Cover: The aim of this study is to describe the frequency of disease activity after discontinuation of DMTs in MS patients included in the Argentinean MS and NMOSD registry., Discusion: Patients with relapsing remitting MS (RRMS) and active secondary progressive MS (SPMS) were included based on the following criteria: they discontinued treatment for more than 6 months, they had been treated with a DMT for ≥2 years, and they had at least 6 months of follow-up in the registry after discontinuation. Demographic and clinical data were collected. Disease activity during follow-up was defined as the presence of a clinical relapse or a new magnetic resonance (MRI) lesion (either new lesions on T2-weighted sequence and/or contrast enhancement). Bivariate analysis was applied to identify clinical and demographic factors related to disease activity., Conclusion: We included 377 patients (75.5% RRMS, 22.5% SPMS) who had discontinued DMTs. The mean (SD) follow-up after discontinuation was 15.7 (7.9) months. After discontinuation, the presence of relapse was detected in 18.8% and 3.5% in RRMS and SPMS, respectively; and new MRI activity in 22% and 3.5%, respectively. We found that higher risk of relapse and MRI activity was associated with younger age (p < 0.001), shorter disease duration (p < 0.001), and RRMS phenotype (p = 0.006). Males showed higher MRI activity (p 0.011). This study provides real-world data that can guide physicians when considering discontinuation of DMTs.