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Effects of a dual intervention (motor and virtual reality-based cognitive) on cognition in patients with mild cognitive impairment: a single-blind, randomized controlled trial

2024 , Buele, Jorge , Avilés-Castillo, Fátima , Carolina Del-Valle-Soto , Varela Aldas, José , Guillermo Palacios-Navarro

Abstract Background The increase in cases of mild cognitive impairment (MCI) underlines the urgency of finding effective methods to slow its progression. Given the limited effectiveness of current pharmacological options to prevent or treat the early stages of this deterioration, non-pharmacological alternatives are especially relevant. Objective To assess the effectiveness of a cognitive-motor intervention based on immersive virtual reality (VR) that simulates an activity of daily living (ADL) on cognitive functions and its impact on depression and the ability to perform such activities in patients with MCI. Methods Thirty-four older adults (men, women) with MCI were randomized to the experimental group (n = 17; 75.41 ± 5.76) or control (n = 17; 77.35 ± 6.75) group. Both groups received motor training, through aerobic, balance and resistance activities in group. Subsequently, the experimental group received cognitive training based on VR, while the control group received traditional cognitive training. Cognitive functions, depression, and the ability to perform activities of daily living (ADLs) were assessed using the Spanish versions of the Montreal Cognitive Assessment (MoCA-S), the Short Geriatric Depression Scale (SGDS-S), and the of Instrumental Activities of Daily Living (IADL-S) before and after 6-week intervention (a total of twelve 40-minutes sessions). Results Between groups comparison did not reveal significant differences in either cognitive function or geriatric depression. The intragroup effect of cognitive function and geriatric depression was significant in both groups (p < 0.001), with large effect sizes. There was no statistically significant improvement in any of the groups when evaluating their performance in ADLs (control, p = 0.28; experimental, p = 0.46) as expected. The completion rate in the experimental group was higher (82.35%) compared to the control group (70.59%). Likewise, participants in the experimental group reached a higher level of difficulty in the application and needed less time to complete the task at each level. Conclusions The application of a dual intervention, through motor training prior to a cognitive task based on Immersive VR was shown to be a beneficial non-pharmacological strategy to improve cognitive functions and reduce depression in patients with MCI. Similarly, the control group benefited from such dual intervention with statistically significant improvements. Trial registration ClinicalTrials.gov NCT06313931; https://clinicaltrials.gov/study/NCT06313931.

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System Identification and Nonlinear Model Predictive Control with Collision Avoidance Applied in Hexacopters UAVs

2022 , Recalde, Luis , Guevara, B.S. , Carvajal, C.P. , Andaluz, V.H. , Varela Aldas, José , Gandolfo, D.C.

Accurate trajectory tracking is a critical property of unmanned aerial vehicles (UAVs) due to system nonlinearities, under-actuated properties and constraints. Specifically, the use of unmanned rotorcrafts with accuracy trajectory tracking controllers in dynamic environments has the potential to improve the fields of environment monitoring, safety, search and rescue, border surveillance, geology and mining, agriculture industry, and traffic control. Monitoring operations in dynamic environments produce significant complications with respect to accuracy and obstacles in the surrounding environment and, in many cases, it is difficult to perform even with state-of-the-art controllers. This work presents a nonlinear model predictive control (NMPC) with collision avoidance for hexacopters’ trajectory tracking in dynamic environments, as well as shows a comparative study between the accuracies of the Euler–Lagrange formulation and the dynamic mode decomposition (DMD) models in order to find the precise representation of the system dynamics. The proposed controller includes limits on the maneuverability velocities, system dynamics, obstacles and the tracking error in the optimization control problem (OCP). In order to show the good performance of this control proposal, computational simulations and real experiments were carried out using a six rotary-wind unmanned aerial vehicle (hexacopter—DJI MATRICE 600). The experimental results prove the good performance of the predictive scheme and its ability to regenerate the optimal control policy. Simulation results expand the proposed controller in simulating highly dynamic environments that showing the scalability of the controller. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.

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Psychosocial Risk and Work Stress in Logistics and Distribution

2023 , Lara Calle, Andrés , Prado D.

The research is focused on studying the psychosocial risk factors and work stress in the logistics and distribution personnel of a company in the city of Latacunga, Ecuador. It contributes to the thematic area of the Psychology of Engineering, and the methodology follows a quantitative approach with a cross-sectional design and correlational scope. For data collection, the evaluation method of psychosocial factors designed by the National Institute of Safety and Health at Work of Spain through the FPSICO 4.0 software and the Work Stress Questionnaire developed by the World Health Organization are used. The study is conducted on 25 workers. The results show a 70% presence of psychosocial risk with a moderate to a high level, and there is low work stress of 68%. To identify if there is a possible relationship between psychosocial risk and work stress, the variables are analyzed. Initially, the Shapiro-Wilk normality test is performed, obtaining values less than 0.05, and there is no homogeneity between variables. Therefore, the non-parametric statistical test of Spearman’s correlation is established, in which a value of 0.38 is obtained, accepting the alternative hypothesis with a low correlation between the variables. In this sense, this demonstrates the importance of evaluating the work environment to identify the existence of risks that may be affecting the performance of workers and the fulfillment of business objectives. Finally, these results allow for creating awareness in the country to reduce or mitigate the existing risks and prioritize the health of workers. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

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Accessibility assessment in mobile applications for android

2020 , Acosta-Vargas, P. , Salvador-Ullauri, L. , Jadán Guerrero, Janio , Guevara Maldonado, César Byron , Sanchez-Gordon, S. , Calle-Jimenez, T. , Lara Álvarez, Patricio , Medina, A. , Nunes, I.L.

At present, the lack of adequate methods to test whether a mobile application is accessible has become a major challenge for accessibility experts. This study was applied to ten mobile applications, the most popular according to PCMAG. We propose to use the Web Content Accessibility Guidelines 2.1 through manual review and automatic review with the Google Play Store Accessibility Scanner validator for the Android. The evaluation results of the mobile applications indicate that the applications are not accessible because they do not comply with the minimum required level proposed by WCAG 2.1. The research proposes suggestions to improve and raise awareness among the designers of mobile applications, in such a way that more inclusive mobile applications accessible to all types of users are built. © Springer Nature Switzerland AG 2020.

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Computerized Planning of Surface Ratios in a Milk Extraction Plant

2023 , Suárez del Villar, Alexis , Álvarez Sánchez, Ana , Galarza Tipantuña A.R.

The research is carried out on the milk extraction process of a farm that has been showing a decrease in monthly income, negatively affecting profits, the economic deficit is affected by the milk sales price of 0.32 dollars per liter being lower than that of competitors, the lack of real historical data on the amount of milk extracted, losing control of expenses, and that the plant is not suitable for the process of extraction and storage of milk, causing the milk to be sold at times at 0.29 dollars per liter. There are multinationals that have submitted proposals for the purchase of the milk product; to close these contracts they ask for compliance with the technical standard: Guide of good practices for milk production, technical resolution No. 0217 fifth revision. 0217 fifth revision, was applied as a solution the systematic planning of the plant layout (SLP) using a methodology based on the application of the Relationship Diagram in CORELAP software, and the Method of the Elimination of the double sense of movements, selecting the second alternative, in addition, A mechanical milk extraction equipment is implemented with a milking capacity of 50 cows in 10 500 s, this is achieved by milking two cows at the same rhythm, the production time is reduced by 75% going from 55827 s to 13950 s, with this time 127 Lt are increased in the daily extraction going from 1373 Lt to 1500 Lt, and the personnel requirement is reduced from 5 to 3 operators. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

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Virtual Reality applications based on activities of daily living (ADL) for cognitive diagnosis and rehabilitation

2022 , Buele, Jorge , Varela Aldas, José , Palacios-Navarro G.

Traditionally, screening tools are available to help diagnose a person's cognitive problem. Therefore, rehabilitation techniques are lab exercises that lack adequate ecological validity. In this paper, we propose to establish the projection of a methodology for the development of serious games based on activities of daily living (ADL). Both for real and immersive environments, to assess what provides better results when applied in healthy patients at first, but with a focus on those suffering from Alzheimer's disease. It is expected that when this research is completed, precedents will be established for the development of new proposals based on virtual environments. © 2022 IEEE.

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Static reactive power compensator design, based on three-phase voltage converter

2021 , Ayala-Chauvin, Manuel Ignacio , Kavrakov B.S. , Buele, Jorge , Varela Aldas, José

At present, electrical network stability is of the utmost importance because of the increase in electric demand and the integration of distributed generation deriving from renewable energy. In this paper, we proposed a static reactive power compensator model with common direct current voltage sources. Converter parameters were calculated and designed to fulfill specifications. In order to ascertain the device response for different operating modes as reactive power consumer and generator, we developed the model’s power and control circuits in Matlab Simulink. Simulations were performed for different conditions, and as a result, the current and voltage waveforms and the circular power chart were obtained. This paper has theoretically proven it is possible to achieve the consumption or generation of purely active or reactive power by implementing a static reactive power compensator with common DC voltage sources. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

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House fly larvae harvest yield using three different rations of wheat brand and pig manure as larval development media [Rendimentos de larvas de moscas em diferentes colheitas com três proporções de farelo de trigo e esterco suíno]

2023 , Cosío E.C. , Reyes R.R. , del Villar Labastida A.S. , Sánchez A.Á. , Morales R.P.

The aim of the research was to compare the yields of house fly larvae using different proportions of wheat bran and swine feces as larval development medium, in a randomized block experimental design with five replications: A-100 % wheat bran; B- 50% wheat bran and 50% swine feces; C- 100% swine feces. Measurements of the temperature of the substrates, as well as the temperature and relative humidity of the place where the flies were developing were made every 24 hours. The larval yield per m2 and kg of substrate, (including the water used to moisten the larval media) were also registered. The wheat bran substrate presented the highest temperature values (36.78 oC), with values above the ambient temperature. The relative humidity varied between 44 and 68%. The amount of water used per square meter was 28.75; 27.72 and 28.87 L for A, B and C treatments, respectively. The highest yield for all substrates was obtained during the first harvest after six days with the highest values for treatment B with 2869.11 g m2-1 and 181.16 g kg-1, respectively. The transformation of the crude protein of the substrates by the fly larvae was between 28.0 and 41.0%, with the highest value for treatment B with 2869,11 g m2 - 1 and 181,16 g kg2-1 . No presence of pathogenic agents was observed in the harvested larvae. © 2023 Universidade Estadual de Mato Grosso do Sul. All rights reserved.

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Design of an Automatic System for the Heat Shrink Blow Molding Process as a Measure to Reduce Ergonomic Risks

2023 , Topon Visarrea, Blanca , Shuguli R. , Ron Valenzuela, Pablo , Castillo J.

In many countries, manual lifting of loads, forced postures and repetitive movements are a source of musculoskeletal injuries in the operators of various machines. On a regular basis, repetitive manual operations, when performed continuously, for a long time and without due precaution, cause physical problems in the operators, affecting the production process. In this work, we present the ergonomic intervention in the manual workstation called heat shrink blowing. For this purpose, we included the analysis of the risk level of the workstation, dimensioning of the vertical linear system, the requirements and a comparison of the times and units produced with the manual method. The workstation was analyzed with the JSI method, and the sizing of the linear system based on the weight of the 3 kg heat gun. The result of this design allows to decrease the risk level of the workstation from JSI=13.5 to 1, due to the replacement of the operator by the system, thus protecting his safety, as well as the operation time varies from 2.8 to 3.1 seconds and the quantity of units produced varies between 9412 to 9600 units. These results are possible because this proposal has been received as an investment to optimize production, as well as a strategy to improve the working conditions and health of its employees. © 2023 IEEE.

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AN ASSESSMENT OF CUBAN FOOD SECURITY BASED ON THE AGRICULTURAL AREA UNDER CULTIVATION AND AGRICULTURAL YIELDS

2022 , Cosío, E.C. , Suárez del Villar, Alexis , Álvarez Sánchez, Ana , Cruz, I.A.

The research was carried out with official data published in the country, collected from official information sources from 2007 to 2019. In the variables analyzed, the following were considered as having high explanatory power: land distribution, total area, agricultural area, cultivated area, yields of selected crops. For the calculation of the nutritional needs of the population, the nutritional recommendations for the Cuban population were taken into account and the productions were grouped ac-cording to the classification established for the food groups in Cuba. The country’s agricultural area is 6400.18 Mha in 2019, which its use decreases for all the items studied, except for banana, bell pepper, bean, lemon, guava and pump fruit. In addition, yields of the main crops are low, as is the productivity of the livestock sector analyzed. To contribute to the achieve-ment of food security for the Cuban population in correspondence with the standards of the National Institute of Nutrition, an area with technological package (irrigation and optimal yields) of 3942577.82 ha is needed, existing agricultural area in the country; and without technological package (without irrigation), an area of 6424285.82 ha, which are insufficient in 23485 ha. © 2022, University of Cienfuegos, Carlos Rafael Rodriguez. All rights reserved.

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