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Nowadays, numerical simulations of wind turbines based on the Reynolds-averaged Navier–Stokes (RANS) formulation are becoming, in terms of computational cost, increasingly more viable tools for geometry optimization and design. Nevertheless, a judicious use of RANS-type methods is still required to guarantee acceptable accuracy at manageable computational cost. Here, we assess the accuracy and cost of several well-known turbulence models (Spalart–Allmaras, k - ε , k - ω SST, along with transitional modelling) with and without a zigzag tape modelling for a representative horizontal axis wind turbine within a range of moderate Reynolds numbers ( Re ≈ 3 × 10 5 to 8 × 10 5 ). This range allowed for the assessment of turbulence models under various complex flow conditions. Significant differences in performance have been found and, for a notable portion of the test cases, the k - ε model was able to deliver good results (similar to k - ω SST results) with a considerably coarser mesh. This suggests that k - ε , although often recognized as less accurate than k - ω SST, might actually be more efficient for wind turbine simulations. Also, although the best results came only with a coupled transition model which required a higher computational cost, this increase in cost is not exceedingly high and might allow for this model’s usage in later design stages. Accordingly, the present study is a valuable source for future wind turbine simulations and design and we hope that it fosters further developments in the field.

The aerodynamic design of a new aircraft concept was investigated through subsonic wind-tunnel testing using 1:28-scale powered models. The aircraft configuration integrates a box-wing layout with engines located at the rear part of the fuselage. Measurements involved a back-to-back comparison between two aircraft models: a podded version whose engines were assembled on pylons and a boundary-layer ingestion (BLI) version that provided several system-level benefits. The flowfield was investigated through the power balance method and a variety of pressure flowfield and inlet flow distortion metrics. The results proved that the BLI configuration enhances the propulsive efficiency by reducing both the electrical power coefficient and the kinetic energy waste due to lower jet velocities. Furthermore, there was a reduction of the total pressure recovery due to pressure gradients inside the duct, thereby causing high distortion. Overall, this research highlights the importance of wind-tunnel testing to bring any aerodynamic technology to a sufficient level of maturity and to enable future new aircraft concepts.

The development of electric aircraft propulsion systems has brought the need for further advancements in the design and testing of small-scale propellers, particularly for emerging applications such as distributed electric propulsion aircraft, electric vertical takeoff and landing vehicles, and drones. This need also extends to the development of horizontal axis wind turbines, autonomous underwater vehicles, tidal turbines, and reduced-scale testing of marine propellers. This study introduces a new load cell design capable of simultaneously measuring thrust and torque in small propeller systems. Unlike commercially available solutions, the proposed design integrates separate deformable elements for each measurement while ensuring compactness and low manufacturing cost. The iterative development process included proof of concept through finite element analysis, experimental calibration, and evaluation of cross-talk effects, leading to an optimized second-generation prototype with improved durability and measurement accuracy. The final design of the load cell demonstrates robust performance in thrust and torque measurements while addressing the limitations of the initial prototypes. These improvements provide a reliable solution for experimental propeller research. The main scientific contribution of this work lies in providing an open source, customizable, and cost-effective load cell capable of decoupled thrust and torque measurements with performance comparable to commercial systems.

Background Sarcoidosis is a multisystemic granulomatous disease of unknown origin. It is characterized by abnormal activation of lymphocytes and macrophages with the formation of granulomas. Most cases have asymptomatic pulmonary involvement. In case of symptoms, they have an excellent response to glucocorticoid therapy. We present a case of sarcoidosis with multi-organ involvement, refractory to multiple treatments including biological. Partial remission was achieved in it. Case presentation We report an interesting case of a 38-years-old Spanish woman treated by Heerfordt’s syndrome (uveitis, parotiditis, fever and facial palsy) plus pulmonary hiliar adenopathy. A sarcoidosis diagnosis was confirmed by lung biopsy. She was initially treated with an 8 weeks course of medium dose oral glucocorticoids and tapered over 8 weeks with improvement. After the suspension of glucocorticoids a relapse occurs with severe ocular involvement and suspicion of neurological involvement. The patient received multiple lines of treatment with poor response. Finally, after the combination of cyclophosphamide with infliximab, the uveitis resolved, improving the neurological symptoms. Conclusions Sarcoidosis is a benign disease in most cases. In a small percentage of cases behaves aggressively, requiring early diagnosis and immunosuppressive treatment to avoid sequelae. An adequate immunosuppressive therapy based on Anti TNF drugs should be started to minimize damage and improve the quality of life.The choice of treatment depends on the type and severity of the disease.

This work offers a vision of physicochemical properties of the soils of Caleta Vítor, Northern Chile, such as: organic matter content, pH, porosity, apparent density, particle density and contamination by the presence of Cu, Pb and Zn in the soils where the abandoned mine Compañía Minera San Carlos is located, areas surrounding the river and the beach. The environmental impact of this abandoned mine is analyzed by evaluating the enrichment factor of the metals and the corresponding geo-accumulation index. The information obtained in this study is compared with those reported by SERNAGEOMIN five years earlier. The results of the enrichment factors based on PEC reach values of up to 664 times above the probable effects of their concentration can be observed and, based on TEC, 3037 times above harmful effects due to the presence of Cu can be observed. The Igeo index calculation shows that the abandoned mine area and samples located in the river area and the beach closest to the mining area can be classified as extremely to highly contaminated with Cu and Pb, while they are not contaminated with Zn. It is also shown that almost all sites in the abandoned mining area have increased after five years their Cu concentration between 2 and 54 times; a similar situation is observed with Pb and to a lesser extent with Zn.

Background/Aims: The evidence regarding the utility of assessing first-trimester adiponectin (ApN) serum levels in early prediction of preeclampsia (PE) and fetal growth restriction (FGR) is contradictory. This study aims to determine the role of maternal serum ApN levels as an early predictor of PE and FGR. Methods: A prospective case-control study among a pregnant population who attended their 11- to 14-week ultrasound scan at the University of Chile’s Clinical Hospital’s Fetal Medicine Unit. We included patients who developed PE or FGR (10 cases per group) and 35 healthy controls. We determined ApN levels in blood samples from these 55 patients using a commercial ELISA kit and assessed the relationship of ApN levels with variables like development of PE, FGR, weight at birth and maternal BMI. Results: There were no significant differences among first-trimester ApN serum levels in the groups. Average concentrations were 8, 6.8 and 10.8 ng/ml for the control, PE and FGR groups, respectively. Conclusion: In our study, maternal serum ApN levels were not useful in predicting subsequent development of PE and FGR. However, maternal serum ApN concentration adjusted by BMI was significantly higher during the first trimester in women who later developed FGR.

El objetivo del presente estudio fue conocer los efectos de una sesión de ejercicio físico aeróbico sobre la actividad eléctrica cerebral durante la resolución de una prueba de atención sostenida. Para ello se evaluó a 14 estudiantes universitarios varones, quienes resolvieron una prueba de atención antes y después de una intervención de 30 minutos de ejercicio físico aeróbico. Para registrar su actividad cerebral se utilizó el dispositivo cerebro-interfaz Emotiv Epoc®. Se analizaron los registros del lóbulo frontal, temporal y occipital en el rango de frecuencia de 13 a 30 Hz (onda beta). Los resultados muestran valores de índices de Hurst menores a 0,5, lo que muestra una actividad antipersistente, es decir, la actividad del cerebro cambia segundo a segundo durante la resolución de la prueba, situación que ocurre antes y después del ejercicio físico. Los sujetos tienden a presentar bajo número de correlaciones entre las regiones cerebrales estudiadas y parece ser que el ejercicio permite mantener un trabajo independiente de diversas regiones de la corteza, mejorando el desempeño en problemas de atención sostenida.

Objective: To evaluate the cyclic fatigue fracture resistance, torsional fatigue, and angular deflection of Reciproc Blue (RB), WaveOne Gold (WOG), One Reci (OR), and Plex RC-One (RC-One) instruments for managing root curvatures in simulated canals.Methods: A sample size calculation determined 10 samples per group (5 instruments for the cyclic fatigue test and 5 for the torsional fatigue test) for detecting significant differences. The study included 40 NiTi instruments (25 mm) from four reciprocating systems groups: RB R25, WOG 25, OR 25, and RC-One 25. Instruments were inspected for defects. Bending tests assessed memory control. Static cyclic fatigue tests used an artificial 60° curved canal with motorized activation. Torsional fatigue followed ISO 3630-1, measuring torque and angular deflection until failure. Fractured surfaces were analyzed using automated image analysis and measured with Rhinoceros 8.0 software. Statistical analysis included central tendency and dispersion measures, followed by ANOVA to identify statistically significant differences between groups.Results: The bending test showed RC-One retained shape after pressure, while RB exhibited moderate resistance. WOG and OR did not demonstrate satisfactory bending resistance. Analysis of cyclic fatigue revealed RC-One had the highest resistance, followed by RB, OR, and WOG (p

Hernán Dario Cerón-Muñoz was not included as an author in the original publication [...]

Background The aim of this study was to measure the dental pulp inflammatory response through neuropeptides (SP and CGRP) as a response to occlusal trauma, orthodontic movements and a combination of both, as well as the angiogenic defense mechanism through VEGF expression, which could be the initial step to mineralized tissue formation. Methods Forty human dental pulp samples were collected from healthy first premolars with extraction indicated due to orthodontic reasons from a sample of 20 patients. Patients were divided into four groups with 10 premolars each (1 mandibular and 1 maxillary premolar from each patient): healthy pulp control group, occlusal trauma group, moderate orthodontic forces group; and occlusal trauma plus moderate orthodontic forces group. Stimuli were applied for 24 h before tooth extraction in all experimental groups. All samples were processed, and SP, CGRP, and VEGF were measured by radioimmunoassay. The Kruskal–Wallis test was performed to assess significant differences among groups and Mann–Whitney’s U post hoc pairwise comparisons were also performed. Results The highest increase in SP, CGRP, and VEGF expressions was found in the occlusal trauma plus orthodontic forces group, followed by the moderate orthodontic forces, the occlusal trauma and the control groups, with statistically significant differences between all groups for each of the 3 peptides analyzed (Kruskal–Wallis p  < 0.001). All possible pairwise post-hoc comparisons were also significant for each peptide analyzed (Mann–Whitney’s U p  < 0.001). Conclusion SP, CGRP, and VEGF expressions significantly increase in human dental pulps when stimulated by occlusal trauma combined with moderate orthodontic forces, as compared with these two stimuli applied independently. Name of the registry: Importance of Neurogenic Inflammation in the Angiogenic Response of the Dental Pulp as a Defensive Response. Trial registration number: NCT03804034. Date of registration: 01/15/2019 Retrospectively registered. URL of trial registry record: https://clinicaltrials.gov/ct2/show/NCT03804034?term=NCT03804034&draw=2&rank=1 .