The Rho-family of small GTPase specific guanine nucleotide exchange factor, GEFT, is expressed at high levels in adult human excitable tissues including the brain, heart, and skeletal muscle. ...Previously, we demonstrated that GEFT is specifically expressed in the adult mouse hippocampus and cerebellum, and that overexpression of this protein can result in neurite and dendrite remodeling. This finding prompted us to explore the expression of GEFT in other tissues, which share common developmental ancestry to the nervous system, specifically the ocular system. Using immunohistochemical analysis specific for GEFT protein expression, we observed the highest ocular expression of GEFT occurring in the neuroblastic layer and differentiating lens fibers of the late-stage mouse embryo, and in the postnatal corneal epithelium, lens epithelium, and throughout the retina. Exogenous expression of GEFT in N/N1003A rabbit lens epithelial cells induced lens fiber differentiation as reflected by cell elongation and lentoid formation, as well as a strong increase in β-crystallin and filensin expression. Moreover, transfection of lens epithelial cells with GEFT resulted in a Rac-1 mediated up-regulation of αA-, αB-, βB-, γC-, or γF-crystallin promoter activities that is in part dependent on the nuclear localization of Rac1. Furthermore, pharmacological inhibition of Rac1 blocked GEFT-induced N/N1003A lens fiber differentiation and βB-crystallin expression in ex vivo mouse lens explants. These results demonstrate for the first time a role for GEFT in lens cell differentiation and mouse eye development. Moreover, GEFT regulation of lens differentiation and eye development occurs through a Rac1-dependent mechanism.
Hybrid core-shell nanostructures consisting of permalloy (Ni80Fe20) and multiferroic(BiFeO3, BFO/BiFe0.95Co0.05O3, BFC) materials were synthesized by a two-step method, based on wet chemical ...impregnation and subsequent electrodeposition within porous alumina membranes. Structural and magnetic characterizations have been done to investigate doping effect on magnetic properties and exchange bias. The magnetometry analysis revealed significant enhancements of the exchange bias and coercivity in NiFe-BFC core-shell nanostructures as compared with NiFe-BFO core-shell nanostructures. The enhancements can be attributed to the effective reduction of ferromagnet domain sizes between adjacent layers of core-shell structure. It indicates that it is possible to improve properties of multiferroic composites by site-engineering method. Our approach opens a pathway to obtain optimized nanostructured multiferroic composites exhibiting tunable magnetic properties.
A mercury-resistant bacterial strain which is able to reduce ionic mercury to metallic mercury was used to remediate in laboratory columns mercury-containing wastewater produced during electrolytic ...production of chlorine. Factory effluents from several chloralkali plants in Europe were analyzed, and these effluents contained total mercury concentrations between 1.6 and 7.6 mg/liter and high chloride concentrations (up to 25 g/liter) and had pH values which were either acidic (pH 2.4) or alkaline (pH 13.0). A mercury-resistant bacterial strain, Pseudomonas putida Spi3, was isolated from polluted river sediments. Biofilms of P. putida Spi3 were grown on porous carrier material in laboratory column bioreactors. The bioreactors were continuously fed with sterile synthetic model wastewater or nonsterile, neutralized, aerated chloralkali wastewater. We found that sodium chloride concentrations up to 24 g/liter did not inhibit microbial mercury retention and that mercury concentrations up to 7 mg/liter could be treated with the bacterial biofilm with no loss of activity. When wastewater samples from three different chloralkali plants in Europe were used, levels of mercury retention efficiency between 90 and 98% were obtained. Thus, microbial mercury removal is a potential biological treatment for chloralkali electrolysis wastewater.
For diesel engines equipped with a combined spiral/tangential inlet, the main object of the valve structure and valve lift dissimilitude strategies is the valve, the changes of both will alter the ...motion state of the in-cylinder airflow, which has an important impact on the formation and combustion of the mixture. In order to investigate the flow performance of valve structure and valve lift dissimilitude, this paper used computational fluid dynamics (CFD) numerical simulation and multi-parameter regression methods to optimize the dual intake valve structure and obtained three valve structures with better intake performance first. Then, the optimized intake valve structure models were combined with the valve lift dissimilitude schemes to conduct steady-flow tests for the intake port. Through the reasonable combining of the two, the intake performance of the original engine was further improved. The results show that the valve structure has a relatively small influence on the intake mass, while it has a greater effect on the formation of the swirl in the cylinder, increasing the swirl ratio by 8.0%. The optimized valve structure model was combined with the valve lift dissimilitude scheme. It was found that the valve structure with optimal intake mass combined with the dissimilitude scheme of the largest valve lift of the spiral inlet could increase the flow coefficient by a maximum of 1.9%. The valve structure of the optimal swirl ratio combined with the dissimilitude scheme of the largest valve lift of the tangential inlet could increase the swirl ratio by a maximum of 9.7%. This study can guide diesel engines with combined intakes to increase the intake mass and improve the intake performance.
When the thicknesses of the outer layers are different in sandwich rolling, based on the different kinds of arrangements with the hard and soft materials the thickness ratio of two outer layers is ...changed differently during the rolling process. After the first analysis of the different outer thicknesses sandwich rolling, the rules for final thickness ratio of the two outer layers are proposed. In soft–hard–soft sheets (s–h–s) the thickness ratio of outer layers is remained in the final bonded sandwich sheet however in hard–soft–hard sheets (h–s–h) the thickness ratio is alleviated by sandwich rolling itself. A model based on slab method is proposed to analyze this phenomenon and 4 groups of experiments with Al and Cu as well as steel are conducted. The results calculated by the model well agree with those measured in the experiments. Then the accuracy and worthy of the model are verified.
•It is the first time that the different outer thicknesses sandwich rolling is researched with analytic method.•Based on the different arrangements of the soft and hard materials, the different outer thicknesses ratio is remained in the final bonded sheet (soft–hard–soft), but this ratio is lessen in the bonded sandwich sheet (hard–soft–hard).•Experiments are conducted with Al–Cu–Al, Cu–Al–Cu and Al–steel–Al as well as steel–Al–steel, the model is verified by the results measured from the experiments.•The rolling forces calculated by this model are also verified by the results recorded in the references.
Abstract
Rollers and wheels are widely used in industry and transportation, but there is seldom direct information about contact forces. A smart roller is introduced which provides real‐time pressure ...measurements from a soft, elastomer‐coated cylinder. The roller is designed for automated fiber placement (AFP) machines, which are widely used in the aerospace industry to manufacture complex composite parts. For optimum process performance, real‐time feedback is highly desirable for detecting flaws during manufacturing. The sensor replaces the elastomer outer layer of a standard roller with 4 by 13 tactile pixels (taxels) of soft capacitive sensors, which provide more than 1 pF of change in capacitance per taxel over a pressure range of 1 MPa. Sensors are made of silicone and mounted on a flexible printed circuit board on which a microcontroller with Bluetooth‐Low‐Energy collects and transmits capacitance data. The sensor dielectric layer is composed of pillars that increase layer compliance and sensitivity while also providing the stiffness of typical industrial rollers. The ability of the roller to measure real‐time local compaction pressure at typical manufacturing speeds enables the monitoring of spatially‐resolved pressure‐time curves, which can be used to predict and control adhesion.
Background
Patients with posttraumatic stress disorder (PTSD) often share co‐morbidity with chronic pain conditions. Recent studies suggest a role of P2X3 receptors and ATP signaling in pain ...conditions. However, the underlying mechanisms of visceral hyperalgesia following exposure to PTSD‐like stress conditions remain unclarified.
Methods
The behavior and hormones relevant for PTSD were studied. Visceromotor responses (VMR) and the abdominal withdrawal reflexes (AWR) to colorectal distention (CRD) were recorded to determine P2X3‐receptor–mediated alteration of hyperalgesia following single‐prolonged stress (SPS) exposure. Immunofluorescence, Western blotting, and patch‐clamp were used.
Key Results
The escape latency, adrenocorticotropic hormone and cortisol were increased on days 7–14. Visceromotor responses and AWR was reduced at day 1 in SPS rats but increased to higher levels than in controls after exposure to day 7. Intrathecal administration of the P2X3‐receptor antagonist TNP‐ATP abolished the CRD response. Based on immunofluorescence and Western blotting analysis, SPS‐treated rats exhibited reduced P2X3 expression in dorsal root ganglia (DRG) after day 1 compared with controls. P2X3 expression in DRG was enhanced on day 7 after SPS and the increase of the P2X3 expression was maintained on day 14 and 21 compared with controls. The P2X3‐receptor agonist α,β‐me ATP (10 μM) induced a fast desensitizing inward current in DRG neurons of both control and SPS‐treated rats. The average peak current densities in SPS‐treated group were increased 3.6‐fold. TNP‐ATP (100 nM) markedly blocked all fast α,β‐me ATP‐induced inward currents in the DRG neurons both in control and SPS‐treated rats.
Conclusions & Inferences
The data indicate an important role of P2X3 signaling in visceral hyperalgesia following PTSD‐like stress.
Patients with posttraumatic stress disorder share co‐morbidity with chronic pain conditions. The purpose was to study the underlying mechanisms of increased pain sensitivity in rats following exposure to posttraumatic stress disorder conditions. Motoric responses to colorectal distention were reduced initially in stress‐exposed rats but increased afterwards to higher levels. Stress‐exposure initially exhibited reduced dorsal root ganglion P2X3 ionic channel expression, which was followed by increased P2X3 expression. The data indicate an important role of P2X3 signaling in visceral pain.
Laser wakefield accelerators (LWFAs) are promising sources of high brightness particle and radiation beams with many possible applications, ranging from scientific research to medicine, industry and ...border security. The Scottish Centre for the Application of Plasma-based Accelerators (SCAPA) is a university-based facility employing the use of two high-power, ultrashort pulse lasers to advance research, development and application of laser-plasma accelerators. Here we report on recent advancements in LWFA research at SCAPA and upcoming research programmes to demonstrate proof-of-concept applications of the LWFA.
ABSTRACT
Based on Insight-HXMT data, we report on the pulse fraction evolution during the 2017–2018 outburst of the newly discovered first Galactic ultraluminous X-ray (ULX) source Swift ...J0243.6+6124. The pulse fractions of 19 observation pairs selected in the rising and fading phases with similar luminosity are investigated. The results show a general trend of the pulse fraction increasing with luminosity and energy at supercritical luminosity. However, the relative strength of the pulsation between each pair evolves strongly with luminosity. The pulse fraction in the rising phase is larger at luminosity below 7.71 × 1038 erg s−1, but smaller at above. A transition luminosity is found to be energy independent. Such a phenomenon is first confirmed by Insight-HXMT observations and we speculate that it may have relation with the radiation-pressure-dominated accretion disc.
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