Sheet failure prediction during forming of advanced high strength steels

The automotive industry has increased significantly the use of advanced high strength steels (AHSS) in many structural components of vehicles, with the aim to reduce weight and also increase safety. The high resistance of these steels is accompanied by a decrease in formability, which makes simulation a requirement to adequately foresee the formability of a stretch formed component. For sheet metal forming, the conventional diagram based in strains, Forming Limit Diagrams (FLD), is often used as a failure criterion, but this approach is not effective when working with AHSS, due to the bigger effect produced by changes on strain paths than conventional steels. This work proposes the use a Forming Limit Stress Diagram (FLSD) based on the main stresses acting on the material. These FLSD has been obtained by the simulation of stretching test. To improve the results, the tensile test curve has been extended by using an optical measuring system and a subsequent adjustment of the stress-strain curve for the material. Finally, simulations and real parts behavior have been compared and the failure predictions models have been discussed.Postprint (published version

Diferencias del autoconcepto físico en practicantes y no practicantes de actividad física en estudiantes universitarios

La presente investigación tuvo como objetivos identificar las diferenciasdel autoconcepto físico en practicantes regulares y no practicantesde actividad física en estudiantes universitarios. Participaron 208 estudiantesuniversitarios entre 18 y 31 años de los cuales el 49% realizan actividadfísica regular y el 51% no practican de forma regular o no realizan ningunaactividad física y se les aplicó el Cuestionario de Autoconcepto Físico (CAF)de Moreno y Cervelló (2005). En todas las dimensiones del autoconceptofísico, así como en las escalas generales de autoconcepto físico y autoconceptogeneral, se encontraron diferencias estadísticamente significativas alobtener p-valores debajo de α=.05, esto indica que las autopercepciones físicasy las autopercepciones generales están medidas por la actividad física,por lo que se sustenta la importancia que tiene la actividad física en losuniversitarios

Análisis numérico de la convección natural en recintos cerrados con distinto factor de forma

pEn este trabajo se utilizó el análisis numérico, aplicando el programa de simulación para ingeniería ANSYS, para establecer la distribución de temperaturas, densidad y velocidades vertical y horizontal en una cavidad cerrada con relación geométrica alto/ancho (emH/E/em) del sistema de 0.5, 1 y 2, temperatura constante en la pared vertical izquierda y derecha de 50 y 20 °C, respectivamente, y condición de frontera adiabática en las paredes horizontales. Lo anterior para un número de Prandtl de 4.83 y Rayleigh de 5.84x10sup7/sup. Al comparar los resultados entre el sistema con emH/E /em= 2 y emH/E /em= 1, se encontró que el valor máximo positivo de la velocidad vertical se incrementó un 26.29 %, el de la velocidad horizontal disminuyó 72.75 % y la temperatura en la zona central de la cavidad disminuyó un 2.46 %. Por otro lado, al comparar los resultados del sistema emH/E /em= 0.5 y emH/E /em= 1, se encontró que el valor máximo positivo de la velocidad vertical aumentó un 7.24 %, el de la velocidad horizontal se incrementó 34.08 % y la temperatura de la zona central del sistema disminuyó un 3.70 %./pp /pp /ppstrongPalabras claves:/strong Convección natural; Cavidad cerrada; ANSYS/p pDOI: a href="http://dx.doi.org/10.5377/nexo.v24i1.589"http://dx.doi.org/10.5377/nexo.v24i1.589/a/p pNexo, Vol. 24, No. 1, pp. 3-10, 2011/pp /

Circular Sponge against miR-21 Enhances the Antitumor Activity of Doxorubicin against Breast Cancer Cells

Breast cancer is the most common type of cancer in women, with chemotherapy being the main strategy. However, its effectiveness is reduced by drug resistance mechanisms. miR-21 is upregulated in breast cancer that has been linked to drug resistance and carcinogenic processes. Our aim was to capture miR-21 with a circular sponge (Circ-21) and thus inhibit the carcinogenic processes and drug resistance mechanisms in which it participates. Proliferation, migration, colony formation, cell cycle, and poly [ADP-ribose] polymerase 1 (PARP-1) and vascular endothelial growth factor (VEGF) detection assays were performed with MCF7 breast cancer cells and MCF10A non-tumor cells. In addition, doxorubicin resistance tests and detection of drug resistance gene expression were performed in MCF7 cells. Reduction in proliferation, as well as migration and colony formation, increased PARP-1 expression, inhibition of VEGF expression and cell cycle arrest in G2/M phase were displayed in the Circ-21 MCF7, which were not observed in the MCF10A cells. Furthermore, in the MCF7 cells, the Circ-21 enhanced the antitumor activity of doxorubicin and decreased the expression of resistance genes: ABCA1, ABCC4, and ABCC5. Based on these results, the use of Circ-21 can be considered a first step for the establishment of an effective gene therapy in the treatment of breast cancer.CTS-107 GroupInstituto de Salud Carlos IIIEuropean Commission PI19/0147

Ametropia detection using a novel, compact wavefront autorefractor

Introduction: Despite the well-known reproducibility issues of subjective refraction, most studies evaluating autorefractors compared differences between the device and subjective refraction. This work evaluated the performance of a novel handheld Hartmann–Shack-based autorefractor using an alternative protocol, which considered the inherent variability of subjective refraction. Methods: Participants underwent an initial measurement with a desktop autorefractor, two subjective refractions (SR1 and SR2) and a final measurement with the QuickSee Free (QSFree) portable autorefractor. Autorefractor performance was evaluated by comparing the differences between the QSFree and each of the subjective refractions with the difference between the subjective refractions (SR1 vs. SR2) using Bland–Altman analysis and percentage of agreement. Results: A total of 75 subjects (53±14years) were enrolled in the study. The average difference in the absolute spherical equivalent (M) between the QSFree and the SR1 and SR2 was ±0.24 and ±0.02D, respectively, that is, very similar or smaller than the SR1 versus SR2 difference (±0.26D). Average differences in astigmatic components were found to be negligible. The results demonstrate that differences between QSFree and both subjective refractions in J0 and J45 were within ±0.50 D for at least 96% of the measurements. The limits of agreement (LOAs) of the differences between QSFree and SR1, as well as QSFree and SR2, were higher than those observed between SR1 and SR2 for M, J0 and J45. Conclusions: A protocol was designed and validated for the evaluation of a refractive device to account for the variability of subjective refraction. This protocol was used to evaluate a novel portable autorefractor and observed a smaller difference between the device and subjective refractions than the difference between the two subjective refraction measurements in terms of mean bias error, although the standard deviation was higherComunidad de Madrid, Grant/Award Number: IND-15478, IND2019/TIC-17116 and IND2020/TIC-17340; Ministerio de Economía y Competitividad, Grant/Award Number: RYC-2016-21125; National Eye Institute, Grant/ Award Number: R44EY025452; Translational Research Institute for Space Health, Grant/ Award Number: NASA NNX16AO69

Singularities of surface mixing activity in the Western Mediterranean influence bluefin tuna larval habitats

Understanding how the surface dynamics of the ocean influence the spawning and larval ecology of many large pelagic species, in particular tuna species, is a major challenge. For temperate tunas, the selection of geographically restricted spawning grounds is influenced by environmental conditions, but the influence of surface mixing properties on the early life stages of these species remains poorly understood. Here, based on ichthyoplankton samples collected over 4 yr and satellite-derived finite size Lyapunov exponents (FSLEs), we examined how horizontal mixing activity drives the probability of presence of Atlantic bluefin tuna Thunnus thynnus larvae. We further analyzed the spatial and temporal scales of the FSLE variability at which the relationship between larval presence and mesoscale activity is maximized. We found that moderate mixing activity strongly favors the spatial-temporal distribution of larval habitats, evidencing an optimal environmental window of bluefin tuna spawning and early life development within the mesoscale dynamics. During the spawning season, the Balearic Sea presents a unique spatial and temporal hydrodynamic scenario within the Western Mediterranean. These results can be used for developing oceanographic indicators and improving larval abundance indices that are currently used in Atlantic bluefin tuna stock assessments.En prensa2,48

The HRA2pl fusion peptide exerts in vitro antiviral activity against human respiratory paramyxoviruses and pneumoviruses

Acute respiratory infections are a group of diseases caused by viruses, bacteria, and parasites that mainly affect children until the age of 5 and immunocompromised senior adults. In Mexico, these infections are the main cause of morbidity in children, with more than 26 million cases of respiratory infections reported by the Secretariat of Health, in 2019. The human respiratory syncytial virus (hRSV), the human metapneumovirus (hMPV), and the human parainfluenza-2 (hPIV-2) are responsible for many respiratory infections. Currently, palivizumab, a monoclonal antibody against the fusion protein F, is the treatment of choice against hRSV infections. This protein is being studied for the design of antiviral peptides that act by inhibiting the fusion of the virus and the host cell. Therefore, we examined the antiviral activity of the HRA2pl peptide, which competes the heptad repeat A domain of the F protein of hMPV. The recombinant peptide was obtained using a viral transient expression system. The effect of the fusion peptide was evaluated with an in vitro entry assay. Moreover, the effectiveness of HRA2pl was examined in viral isolates from clinical samples obtained from patients with infections caused by hRSV, hMPV, or hPIV-2, by evaluating the viral titer and the syncytium size. The HRA2pl peptide affected the viruses’ capacity of entry, resulting in a 4-log decrease in the viral titer compared to the untreated viral strains. Additionally, a 50% reduction in the size of the syncytium was found. These results demonstrate the antiviral potential of HRA2pl in clinical samples, paving the way toward clinical trials

Lipid Metabolism Alterations in a Rat Model of Chronic and Intergenerational Exposure to Arsenic

Chronic exposure to arsenic (As), whether directly through the consumption of contaminated drinking water or indirectly through the daily intake of As-contaminated food, is a health threat for more than 150 million people worldwide. Epidemiological studies found an association between chronic consumption of As and several pathologies, the most common being cancer-related disorders. However, As consumption has also been associated with metabolic disorders that could lead to diverse pathologies, suchas type 2 diabetes mellitus, nonalcoholic fatty liver disease, and obesity. Here, we used ultra-performance liquid chromatography (UPLC) coupled to electrospray ionization/quadrupole time-of-flight mass spectrometry (ESI-QToF) to assess the effect of chronic intergenerational As exposure on the lipid metabolism profiles of serum from 4-month-old Wistar rats exposed to As prenatally and also during early life in drinking water (3 ppm). Significant differences in the levels of certain identified lyso-phospholipids, phosphatidylcholines, and triglycerides were found between the exposed rats and the control groups, as well as between the sexes. Significantly increased lipid oxidation determined by the malondialdehyde (MDA) method was found in exposed rats compared with controls. Chronic intergenerational As exposure alters the rat lipidome, increases lipid oxidation, and dysregulates metabolic pathways, the factors associated with the chronic inflammation present in different diseases associated with chronic exposure to As (i.e., keratosis, Bowen’s disease, and kidney, liver, bladder, and lung cancer)