The purpose of this study was to analyze the relationships between cybervictimization in social networks, problematic smartphone use, aggressive behaviors, and prosocial altruistic tendencies in ...young adults. The sample consisted of 601 young adults (mean age = 19.96 years; SD = 2.27; 69.1% female) who were administered online assessments of experiences of humiliation on networks, problematic smartphone use, prosocial altruistic tendencies, and aggressiveness. Results indicated significant indirect effects of cyber victimization on aggressiveness and prosocial altruistic tendencies through problematic smartphone use. Problematic cell phone use explained the relationships between online humiliation and aggressive and prosocial altruistic behaviors. The results confirmed the positive relationship between cybervictimization and problematic cell phone use, consistent with previous research. However, the negative relationship between cybervictimization and altruistic prosocial tendencies was not corroborated. The findings emphasize the need to promote actions that foster social connectedness and interdependence among young individuals to develop their identity within the community.The purpose of this study was to analyze the relationships between cybervictimization in social networks, problematic smartphone use, aggressive behaviors, and prosocial altruistic tendencies in young adults. The sample consisted of 601 young adults (mean age = 19.96 years; SD = 2.27; 69.1% female) who were administered online assessments of experiences of humiliation on networks, problematic smartphone use, prosocial altruistic tendencies, and aggressiveness. Results indicated significant indirect effects of cyber victimization on aggressiveness and prosocial altruistic tendencies through problematic smartphone use. Problematic cell phone use explained the relationships between online humiliation and aggressive and prosocial altruistic behaviors. The results confirmed the positive relationship between cybervictimization and problematic cell phone use, consistent with previous research. However, the negative relationship between cybervictimization and altruistic prosocial tendencies was not corroborated. The findings emphasize the need to promote actions that foster social connectedness and interdependence among young individuals to develop their identity within the community.
The aim of this work is to present an experimental procedure at laboratory scale that was developed to validate a new CFD-based methodology for the estimation of water evaporation rate in indoor ...swimming pools, under a wide range of convective flow conditions (36 experiments) and focussing on the most common operation conditions of these facilities: low air mean velocities (0.08–0.24 m/s), and water and air temperatures in the ranges 24-28 °C and 26-30 °C, respectively. One of the main hypotheses of the simulation methodology set a free slip wall condition (no shear stress) at the air-water interface, based on the fact that the dynamic boundary layer depth will be smaller than the thickness of the thermal and humidity boundary layers in this kind of flows. The comparison between simulated and experimental results show that the modelling strategy proposed is a promising tool, with average relative errors of 9% for the typical mixed convection flows in indoor swimming pools.
•New CFD-based method to calculate evaporation rate.•Main hypotheses set no shear stress at the air-water interface.•The model was validated with an experimental procedure at laboratory scale.•Good results with low relative errors for indoor swimming pool conditions.
•A new CFD-based method to calculate evaporation rate.•Main hypotheses set no shear stress at the air-water interface.•The model was experimentally validated with data from test chambers and a real ...swimminng-pool.•Results were quite satisfactory with low relative errors.
This paper presents a new methodology in which a computational fluid dynamics model is applied to estimate water evaporation rate in indoor swimming pools. This rate is needed to achieve a suitable energy performance of ventilation and dehumidification systems. The main hypotheses of the model set the following boundary conditions at the air-water interface: air temperature equal to water temperature, water vapour concentration equal to saturation humidity of air at water temperature and free slip wall condition (no shear stress). This last condition can be justified by the fact that Prandtl and Schmidt turbulent numbers are usually less than one in this kind of flows. Consequently, the dynamic boundary layer depth will be smaller than the thickness of the thermal and humidity boundary layers. The model was experimentally validated by using data from three different test chambers and from a real swimming-pool. A total of 233 different flow conditions were simulated. The results were quite satisfactory, with a relative error of only 3% in the simulations of the real swimming-pool and a total average relative error smaller than 9%.
Bioethics training is essential for healthcare professionals as it enables them to address ethical dilemmas in their clinical practice. However, there is still a lack of rigorous teaching programs, ...and assessing bioethical knowledge poses challenges.
Systematic review using the PRISMA method.
Analysis of 27 studies reveals a lack of ethical knowledge and skills among healthcare professionals and students. Specific training in bioethics is effective in developing bioethical competencies. Different approaches have been employed, including integrated training in academic curricula and intensive or ongoing programs. The results demonstrate improvements in knowledge, attitudes, and ethical values, although regularly updating these courses is recommended.
Specific training, institutional support, and considering regional and disciplinary differences are necessary to enhance ethics in the practice of healthcare professionals.
https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023437146, identifier CRD42023437146.
The calculation of sunlit surfaces in a building has always been a relevant aspect in building energy simulation programs. Due to the high computational cost, some programs use algorithms for shading ...calculation for certain solar positions after discretization of hemispherical sky. The influence of the level of discretization on the estimation of incident direct radiation on building surfaces, as well as on the required computational times, are studied in this work. The direct solar energy on a window for a year, with simulation time steps of five minutes, has been simulated by using an algorithm based on Projection and Clipping Methods. A total of 6144 simulations have been carried out, varying window sizes, window orientations, typologies of shading devices, latitudes and discretization levels of the hemispherical sky. In terms of annual incident solar energy, the results show that maximum error values are about 5% for a low level of angular discretization. Errors up to 22% in hourly incident solar energy have been estimated for some of the configurations analysed. Furthermore, a great number of configurations show errors of shading factor on a window of up to 30%, which could be most relevant in studies of natural lighting. The study also shows that the improvement achieved by the most accurate discretization level implies an increase in computational cost of about 30 times.
In the last decade, a group of Ca2+ channels called Piezo were discovered, demonstrating a decisive role in the cellular response to mechanical stimuli and being essential in the biological behavior ...of cells regarding the extracellular compartment. Several investigations have suggested a potential role in carcinogenesis, with a tumor suppressor role in some cases but increased expression in several high-grade neoplasms. Regarding Piezo2 expression in mammary gland neoplasms, a protective role for Piezo2 was initially suggested, but a subsequent study demonstrated a relationship between Piezo2 expression and the highly aggressive triple-negative phenotype of breast carcinoma. A cohort of 125 patients with clinical follow-up was chosen to study Piezo2 expression and clarify its clinical implications using the same immunohistochemical evaluation performed for other breast carcinoma parameters. Fisher’s exact test was chosen to identify potential relationships between the different variables. A significant association was found with the Ki67 proliferation index, but not with mitoses. The tendency of most proliferative tumors was to have an increased score for Piezo2. A similar association was found between Piezo2 expression and perineural invasion.
ABSTRACT
The prevalent numerical models for simulating axially finned heat exchangers with phase change materials (PCMs) and water as the heat transfer fluid rely on computational fluid dynamics ...(CFD) techniques, with a primary focus on phase change modeling. However, the computational demands of these models, incorporating phase change effects and resolving PCM movement in the liquid state, are substantial. From experiments suggesting that conduction in the solidified PCM around the finned tube dominates heat transfer during the heat discharge process, this article introduces a simplified CFD‐based model in which convective flow of the PCM is neglected. The model is experimentally validated using a 1‐m‐long axially finned heat exchanger prototype with four fins, recording temperatures under different water flow rates and orientations (horizontal and vertical). Results show that the proposed model predicts outlet water temperature satisfactorily, with absolute errors below 1.0°C and 2.2°C for the horizontal and vertical orientations, respectively. Additionally, the model can capture the temperature trend inside the PCM for the horizontal orientation.
•A new analytical approach based on Heisler and Gröber’s solution is presented.•Sufficiently accurate and might be used in the design of this kind of exchangers.•Few analytical models to estimate ...energy transfer by finned exchangers easily.•The model reproduces CFD numerical results fairly well (mean RMSE smaller than 4%).
Phase change materials have demonstrated interesting advantages in solar energy storage systems to produce domestic hot water although more efficient heat exchangers are required. Among the different exchanger typologies, longitudinally finned exchangers are widespread. However, according to scientific literature, there is a lack of analytical models able to estimate the thermal power transferred by this kind of exchangers easily. This paper shows a practical and easy to apply analytical model that has been built for that type of exchangers. Thus, based on a change of the solution given by Heisler and Gröber for an infinitely long cylinder, this new analytical approach characterises the thermal energy discharged in terms of dimensionless numbers. The adjustment of the analytical model was achieved from the results provided by a CFD numerical model which was previously validated from experimental data. 544 numerical simulations of the system were carried out varying the Biot number and a surface factor number from 1 to 100 and 3 to 15, respectively. An analytical equation that estimates the energy discharged is provided as a function of Fourier, Biot, and Stefan numbers and the surface factor number, related to the exchanger geometry. An average value of the root mean square error smaller than 4% indicates that the proposed model is sufficiently accurate and might be used in the design stages of this kind of devices. A further validation of the analytical model against experimental observations will be carried out in a future stage of model development.
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