Transient Thermal Analysis of a Railroad Bearing Adapter for Optimal Placement of Onboard Sensors

Bearing temperature serves as an important metric used in identifying defective bearings in the rail industry. Current defect detection systems, such as the Hot Box Detectors (HBDs), are used to measure the temperature of freight car roller bearings. The HBD is a wayside device that utilizes a non-contact infrared sensor to determine the operating temperature of a railroad bearing as it passes over the HBD. Railroads analyze the data collected by HBDs to detect and flag defective bearings. If the operating temperature of a bearing surpasses a predetermined threshold, an emergency stop is initiated, and the bearing is removed from service and sent for inspection. One major drawback of HBDs is that they have been associated with many “false positives,” which has resulted in costly train stoppages and delays. To combat that, researchers have opted to use wireless onboard sensor devices mounted directly on the bearing adapter. One such device is the wireless onboard health monitoring system developed by the University Transportation Center for Railway Safety (UTCRS) that utilizes temperature and vibration sensors to detect the condition of rolling stock. However, because the device is affixed to the bearing adapter and not the bearing itself, the strategic placement of the temperature sensor on the adapter is crucial in minimizing the thermal lag associated with the heat transfer from the bearing to the location where the temperature is measured, as this will directly affect the accuracy of the readings. By conducting a transient heat transfer finite element analysis (FEA), the estimated time-lag and the temperature distribution within the bearing adapter can be determined. To validate the accuracy of the transient FEA model, the results were compared to data acquired from laboratory testing performed on the UTCRS dynamic bearing test rigs. The results obtained in this study can be used to identify optimal anchor points for the temperature sensors on the bearing adapter, and in turn, increase the proficiency of wireless onboard sensor devices in detecting defective components

Improved Carbohydrate Metabolism After Bariatric Surgery Raises Antioxidized LDL Antibody Levels in Morbidly Obese Patients

OBJECTIVE—Antioxidized LDL (anti-oxLDL) antibodies have recently been suggested to be protective against the development of diabetes. We measured the changes in anti-oxLDL antibody levels in the inverse situation of improvement in carbohydrate metabolism

Examinig the mediating role of coping and emotion regularion in stress models in adolescents

The aim of this research was to analyze the relationship between stressful events, coping, and emotion regulation in adolescents from marginalized settings. A cross-sectional study was conducted with 523 adolescents aged 13 to 15 years. The Global Scale of Perceived Stress for Adolescents, the Coping Scale for Adolescents, and the Multidimensional Scale of Emotion Regulation for Adolescents, were used. Several mediation models were tested considering whether coping mediated the relationship between stressful events and emotion regulation responses, or, on contrary, emotion regulation assumes a mediating role between stressful events and coping. Data indicate significant direct and indirect effects in all models, with the highest explained variance in the models which included emotion regulation as a mediating variable. Results are discussed considering the role of coping and emotion regulation as mediating variables, and their relationship with diverse stressful events. In this research, emotion regulation strategies lead to adolescent coping

Thermal and phase transformations analysis in a PREMOMET® steel

Thermal analysis in a PREMOMET® steel has been performed by differential scanning calorimetry (DSC) and highresolution dilatometry. The phase transformation temperatures (Ac1, Ac3, Ms and Mf) of this steel were obtained by the two methods at different heating rates showing good agreement between both techniques. The enthalpy of α-γ transformation for this steel was measured using the thermograms acquired by DSC and microstructure was analyzed by scanning electron microscope (SEM). The results showed that this steel retained a martensitic structure for all conditions

Thermal and phase transformations analysis in a PREMOMET® steel

Thermal analysis in a PREMOMET® steel has been performed by differential scanning calorimetry (DSC) and highresolution dilatometry. The phase transformation temperatures (Ac1, Ac3, Ms and Mf) of this steel were obtained by the two methods at different heating rates showing good agreement between both techniques. The enthalpy of α-γ transformation for this steel was measured using the thermograms acquired by DSC and microstructure was analyzed by scanning electron microscope (SEM). The results showed that this steel retained a martensitic structure for all conditions

Analysis of a spatial Lotka-Volterra model with a finite range predator-prey interaction

We perform an analysis of a recent spatial version of the classical Lotka-Volterra model, where a finite scale controls individuals' interaction. We study the behavior of the predator-prey dynamics in physical spaces higher than one, showing how spatial patterns can emerge for some values of the interaction range and of the diffusion parameter.Comment: 7 pages, 7 figure

Resistin Regulates Pituitary Lipid Metabolism and Inflammation In Vivo

The adipokine resistin is an insulin-antagonizing factor that also plays a regulatory role in inflammation, immunity, food intake, and gonadal function and also regulates growth hormone (GH) secretion in rat adenopituitary cells cultures with the adipokine. Although adipose tissue is the primary source of resistin, it is also expressed in other tissues, including the pituitary. The aim of this study is to investigate the possible action of resistin on the lipid metabolism in the pituitary gland in vivo (rats in two different nutritional status, fed and fast, treated with resistin on acute and a chronic way) and in vitro (adenopituitary cell cultures treated with the adipokine). Here, by a combination of in vivo and in vitro experimental models, we demonstrated that central acute and chronic administration of resistin enhance mRNA levels of the lipid metabolic enzymes which participated on lipolysis and moreover inhibiting mRNA levels of the lipid metabolic enzymes involved in lipogenesis. Taken together, our results demonstrate for the first time that resistin has a regulatory role on lipid metabolism in the pituitary gland providing a novel insight in relation to the mechanism by which this adipokine can participate in the integrated control of lipid metabolism

Sperm Hyperactivation and Capacitation Induced By Light Stimuli in Cryopreserved Semen

In mammals, such as rabbits, there are some factors involved in possible fertilization, from complex changes in the membrane of the sperm to obstruction or non-existent of vas deferens, which creates problems in the number and quality of sperm. In this work, we report the effects of rabbit sperm motility and capacitation of cryopreserved semen samples under light stimuli. The sperm velocities were correlated with the percentage of capacitated and non-capacitated sperm seen with a fluorescent dye. Consequently, we analyzed the specific correlations between irradiation times, supplied energy, and fertility parameters. KEYWORDS THAT SEARCHED RELATED TO THE ARTICLE ON THE WEB sperm meaning, capacitation, human sperm, capacitation occurs in, what is sperm, capacitation of sperm, sperm lifetime, fertilization definition, fertilization meaning, capacitation meaning, mechanism of fertilization,sperm capacitation, capacitate meaning, fertilization takes place in, capacitate, capacitation of sperm occurs in, capacitation of sperms, capacitated, definition of fertilizatio

A mathematical modelling framework for the regulation of intra-cellular OCT4 in human pluripotent stem cells

Human pluripotent stem cells (hPSCs) have the potential to differentiate into all cell types, a property known as pluripotency. A deeper understanding of how pluripotency is regulated is required to assist in controlling pluripotency and differentiation trajectories experimentally. Mathematical modelling provides a non-invasive tool through which to explore, characterise and replicate the regulation of pluripotency and the consequences on cell fate. Here we use experimental data of the expression of the pluripotency transcription factor OCT4 in a growing hPSC colony to develop and evaluate mathematical models for temporal pluripotency regulation. We consider fractional Brownian motion and the stochastic logistic equation and explore the effects of both additive and multiplicative noise. We illustrate the use of time-dependent carrying capacities and the introduction of Allee effects to the stochastic logistic equation to describe cell differentiation. We conclude both methods adequately capture the decline in OCT4 upon differentiation, but the Allee effect model has the advantage of allowing differentiation to occur stochastically in a sub-set of cells. This mathematical framework for describing intra-cellular OCT4 regulation can be extended to other transcription factors and developed into predictive models