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Agro-industrial waste biosorbents of arabica-coffee (WCA) and theobroma-cocoa (WCT) have been characterized and tested to remove Pb(II) from aqueous media. The maximum adsorption capacity of WCA and WCT (qmax = 158.7 and 123.5 mg·g-1, respectively) is comparable or even higher than for several other similar agro-industrial waste biosorbents reported in the literature. Structural and morphological characterization were performed by infrared spectrometry with Fourier transform (FT-IR), scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS), and charge measurements at the zero point charge (pHPZC). Both biosorbents, WCA and WCT, show cracked surfaces with heterogeneous plates which ones include functional adsorption groups such as OH, C = O and C-O-C. Optimal Pb(II) adsorption occurs for a pH between 4 and 5 at [WCA] and [WCT] dose concentrations of 2 g·L-1. We found that the adsorption process follows pseudo-second order kinetics with a rapid growth rate (almost six times larger for WCA than for WCT), basically controlled by the chemisorption process. The regeneration of both biosorbents was carried out in an eluent of 0.1M HNO3 and they can be efficiently reused up to 5 times.

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The main objective of this study is to model the concentration of ozone in the winter season on air quality through machine learning algorithms, detecting its impact on population health. The study area involves four monitoring stations: Ate, San Borja, Santa Anita and Campo de Marte, all located in Metropolitan Lima during the years 2017, 2018 and 2019. Exploratory, correlational and predictive approaches are presented. The exploratory results showed that ATE is the station with the highest prevalence of ozone pollution. Likewise, in an hourly scale analysis, the pollution peaks were reported at 00:00 and 14:00. Finally, the machine learning models that showed the best predictive capacity for adjusting the ozone concentration were the linear regression and support vector machine.

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This research program investigated the effects of layer thickness (50 µm and 100 µm) on the microstructure and mechanical properties of electron beam powder bed fusion (EBPBF) additive manufacturing of Inconel 625 alloy. The as-built 50 µm and 100 µm layer thickness components were also heat treated at temperatures above 1100 °C which produced a recrystallized grain structure containing annealing twins in the 50 µm layer thickness components, and a duplex grain structure consisting of islands of very small equiaxed grains dispersed in a recrystallized, large-grain structure containing annealing twins. The heat-treated components of the microstructures and mechanical properties were compared with the as-built components in both the build direction (vertical) and perpendicular (horizontal) to the build direction. Vickers microindentation hardness (HV) values for the vertical and horizontal geometries averaged 227 and 220 for the as-built 50 µm and 100 µm layer components, respectively, and 185 and 282 for the corresponding heat-treated components. The yield stress values were 387 MPa and 365 MPa for the as-built horizontal and vertical 50 µm layer geometries, and 330 MPa and 340 MPa for the as-built 100 µm layer components. For the heat-treated 50 µm components, the yield stress values were 340 and 321 MPa for the horizontal and vertical geometries, and 581 and 489 MPa for the 100 µm layer components, respectively. The elongation for the 100 µm layer as-built horizontal components was 28% in contrast with 65% for the corresponding 100 µm heat-treated layer components, an increase of 132% for the duplex grain structure.

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A total of 188,859 meteorological-PM[Formula: see text] data validated before (2019) and during the COVID-19 pandemic (2020) were used. In order to predict PM[Formula: see text] in two districts of South Lima in Peru, hourly, daily, monthly and seasonal variations of the data were analyzed. Principal Component Analysis (PCA) and linear/nonlinear modeling were applied. The results showed the highest annual average PM[Formula: see text] for San Juan de Miraflores (SJM) (PM[Formula: see text]-SJM: 78.7 [Formula: see text]g/m[Formula: see text]) and the lowest in Santiago de Surco (SS) (PM[Formula: see text]-SS: 40.2 [Formula: see text]g/m[Formula: see text]). The PCA showed the influence of relative humidity (RH)-atmospheric pressure (AP)-temperature (T)/dew point (DP)-wind speed (WS)-wind direction (WD) combinations. Cool months with higher humidity and atmospheric instability decreased PM[Formula: see text] values in SJM and warm months increased it, favored by thermal inversion (TI). Dust resuspension, vehicular transport and stationary sources contributed more PM[Formula: see text] at peak times in the morning and evening. The Multiple linear regression (MLR) showed the best correlation (r = 0.6166), followed by the three-dimensional model LogAP-LogWD-LogPM[Formula: see text] (r = 0.5753); the RMSE-MLR (12.92) exceeded that found in the 3D models (RMSE [Formula: see text]) and the NSE-MLR criterion (0.3804) was acceptable. PM[Formula: see text] prediction was modeled using the algorithmic approach in any scenario to optimize urban management decisions in times of pandemic.

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Vehicles are quite possibly the main sources of particulate matter, and their emissions can cause damage to surrounding ecosystems. Traditional atmospheric monitoring, however, is expensive. Therefore, airborne biomonitoring is an alternative method that allows for air quality assessment. In this study, we evaluated air quality at a federal highway (BR-040) close to Atlantic Rainforest remnants by quantifying metals in biomonitor tissues by ICP-MS. Tillandsia usneoides and Tillandsia stricta plants were relocated to the investigation zone and collected after five months of exposure. Metal concentration profiles were evaluated using statistical analyses, namely exposure-to-reference (ER) ratios and enrichment factors (EF). Results indicate that V, Cr, Fe, Cu, Zn and Sn enrichment were observed in all study sites. The EF for Cr, Mn, Pb, Ni, Co, Cu, Zn, Cd, and Sn ranged from high to very high, indicating anthropogenic sources. Both species were effective atmospheric biomonitors, proving to be an important tool, mainly in areas where conventional monitoring is not possible.

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In the present study, an urban and industrial area were evaluated through a biomonitoring study employing the Tillandsia purpurea and T. latifolia species as a biomonitor. Plants were collected from a non-contaminated area and transplanted and exposed for three months into study areas to determine metal accumulation. Sixteen elements (Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Ni, Pb, Rb, Sb, V, and Zn) were measured using ICP-MS analysis. Datasets were assessed by one-way ANOVA, exposed-to-baseline (EB) ratio, and principal component analysis. Results showed significant differences among study areas for most elements, but no differences were found between species. According to EB ratios, As, Cd, Cr, Cu, Fe, Ni, Pb, Sb, V, and Zn showed EB ratios > 1.75 for both Tillandsia species around the industrial area, indicating influence from the Smelter plant. Ba, Sb, and Zn showed EB ratios > .1.75 in the urban area for both plants, indicating the releasing of pollutants from vehicular sources. PCA showed that most elements are derived from vehicular sources, industrial activities, and dust resuspension.

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Arsenic (As) causes health effects, especially cancer. Rice (Oryza sativa L.) can contain high As concentrations. Using ICP-MS, we quantified the total As (tAs) levels in the main brands of rice (n = 103) and infant cereals (n = 27) consumed by Brazilians. The levels were compared to the maximum limits prescribed by regulatory agencies. We estimated the daily intake (EDI) of As by Brazilians by combining the mean As concentration determined in the white rice samples with per capita daily consumption divided by the average body weight as reported by the Brazilian Institute of Geography and Statistics in 2010. The possible health risk for consumers was assessed by calculating the margin of exposure (MOE) as prescribed by the Joint FAO/WHO Expert Committee on Food Additives (JECFA). Moreover, tAs was determined in 11 pesticides used by Brazilian farmers. The tAs levels in the rice ranged from 0.003 to 1.3 mg kg-1. Approximately 27% of the white rice contained tAs levels above the limit set by Mercosul (0.3 mg kg-1) and 45% were above the limit set by the European Commission (0.2 mg kg-1). In the infant cereals, tAs levels ranged from 0.003 to 0.243 mg kg-1. In the pesticides, tAs levels ranged from 0.005 to 0.315 mg L-1. The EDI showed that, on average, Brazilians consume 4.13 µg As kg-1 BW weekly. In addition, a low MOE was observed, demonstrating that high use of rice presents a risk of high inorganic (iAs) exposure, which represents a public health concern.

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ABSTRACT Objective To examine the association among six forms of violence and their levels among Peruvian university students from a public University in Peru's Junin region. Materials and Methods A cross-sectional study of students of both sexes from the Faculty of Education. Sampling comprised 961 voluntary students (629 females and 332 males) studying in the education faculty from the National University of Center of Perú. Data were collected in the period July-December 2019 using the Domestic Violence Measurements Scale (VIFJ4), which assessed six forms of violence (physical, psychological, sexual, social, patrimonial, and gender). These variables were assessed through three levels of violence (mild, moderate, and severe). Results All student felt violence in their six forms. A higher percentage of violence was found in females than males. According severe level the forms of violence were ordered as follow: physical > psychological > patrimonial > social > gender. For moderate level: social > sexual > physical > gender > patrimonial > psychological, and mild level: psychological > patrimonial > gender > social > physical > sexual. Conclusion It was confirmed that there are different forms of violence and their levels in both males and females. This knowledge will serve as a basis for the development and implementation of educational programs that help university students to establish adequate behavior and mental health.(AU)

RESUMEN Objetivo Examinar la asociación entre seis formas de violencia y sus niveles entre estudiantes universitarios peruanos de una universidad pública en la región peruana de Junín. Materiales y Métodos Un estudio transversal de estudiantes de ambos sexos de la Facultad de Educación. El muestreo incluyó a 961 estudiantes voluntarios (629 mujeres y 332 hombres) que estudiaban en la Facultad de Educación de la Universidad Nacional del Centro del Perú. Los datos se recopilaron en el período de julio a diciembre de 2019 utilizando la escala de medidas de violencia doméstica VIFJ4, que evaluó seis formas de violencia (física, psicológica, sexual, social, patrimonial y de género). Estas variables fueron evaluadas a través de tres niveles de violencia (leve, moderada y severa). Resultados Todos los estudiantes sintieron violencia en sus seis formas. Se encontró un mayor porcentaje de violencia en mujeres que en hombres. Según el nivel severo, las formas de violencia se ordenaron de la siguiente manera: física > psicológica > patrimonial > social > de género. Para nivel moderado: social > sexual > físico > género > patrimonial > psicológico; nivel leve: psicológico > patrimonial > género > social > físico > sexual. Conclusión Se confirmó que existen diferentes formas de violencia y sus niveles tanto en hombres como en mujeres. Este conocimiento servirá como base para el desarrollo e implementación de programas educativos que ayuden a los estudiantes universitarios a establecer un comportamiento y una salud mental adecuados.(AU)

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OBJECTIVE: To examine the association among six forms of violence and their levels among Peruvian university students from a public University in Peru's Junin region. MATERIALS AND METHODS: A cross-sectional study of students of both sexes from the Faculty of Education. Sampling comprised 961 voluntary students (629 females and 332 males) studying in the education faculty from the National University of Center of Perú. Data were collected in the period July-December 2019 using the Domestic Violence Measurements Scale (VIFJ4), which assessed six forms of violence (physical, psychological, sexual, social, patrimonial, and gender). These variables were assessed through three levels of violence (mild, moderate, and severe). RESULTS: All student felt violence in their six forms. A higher percentage of violence was found in females than males. According severe level the forms of violence were ordered as follow: physical > psychological > patrimonial > social > gender. For moderate level: social > sexual > physical > gender > patrimonial > psychological, and mild level: psychological > patrimonial > gender > social > physical > sexual. CONCLUSION: It was confirmed that there are different forms of violence and their levels in both males and females. This knowledge will serve as a basis for the development and implementation of educational programs that help university students to establish adequate behavior and mental health.

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In the present study, in situ lichens (Flavoparmelia caperata) were used to assess the deposition of atmospheric trace elements in the metropolitan area of Huancayo (Junín, Peru). In total, ten sampling sites were chosen and categorized as urban, peri-urban (rural-urban) and rural areas according to land use. In addition, samples were also collected from a non-contaminated area categorized as a control site. The concentrations of 16 trace elements were measured using an inductively coupled plasma mass spectrometer (ICP-MS) and examined by enrichment factor (EF), hierarchical cluster analysis (HCA), and principal component analysis (PCA). Twelve of the 16 trace elements in urban and peri-urban sites present concentration higher than those at the rural and control sites (p < 0.05). The EF results revealed significant enrichment (at least twice that of the control site) of Ba, Cr, Cd, Pb, Sb, V, and Zn at most sites. PCA and HCA showed that more elements were derived from vehicular sources and fewer from agricultural and natural sources.

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