Supply of methionine and arginine alters phosphorylation of mechanistic target of rapamycin (mTOR), circadian clock proteins, and alpha-s1-casein abundance in bovine mammary epithelial cells

[EN] Methionine (Met) and arginine (Arg) regulate casein protein abundance through alterations in activity of the mechanistic target of rapamycin complex 1 (mTORC1) signaling pathway. A potential role for the circadian clock network on the regulation of protein synthesis, partly via activity of mTORC1, has been highlighted in non-ruminants. The main objective of the study was to determine in ruminant mammary cells alterations in mRNA, protein abundance and phosphorylation status of mTORC1-related upstream targets, circadian clock proteins, and protein kinase AMP-activated catalytic subunit alpha (AMPK) in relation to alpha-s1-casein protein (CSN1S1) abundance in response to greater supply of Met and Arg alone or in combination. Primary bovine mammary epithelial cells (BMEC) were incubated for 12 h in a 2 x 2 arrangement of treatments with control media (ideal profile of amino acids, IPAA), or media supplemented with increased Met (incMet), Arg (incArg), or both (incMet + incArg). Data were analyzed testing the main effects of Met and Arg and their interaction. Among 7 amino acid (AA) transporters known to be mTORC1 targets, increasing supply of Arg downregulated SLC1A5, SLC3A2, SLC7A1, and SLC7A5, while increasing supply of Met upregulated SLC7A1. mRNA abundance of the cytosolic Arg sensor (CASTOR1) was lower when supply of Arg and Met alone increased. p-TSC2 (TSC complex subunit 2) was greater when the Arg supply was increased, while the phosphoralation ratio of p-AKT (AKT serine/threonine kinase 1):total (t) AKT and p-AMPK:tAMPK were lower. In spite of this, the ratio of p-mTOR:tmTOR nearly doubled with incArg but such response did not prevent a decrease in CSN1S1 abundance. The abundance of period circadian regulator 1 (PER1) protein nearly doubled with all treatments, but only incMet + incArg led to greater clock circadian regulator (CLOCK) protein abundance. Overall, data suggest that a greater supply of Met and Arg could influence CSN1S1 synthesis of BMEC through changes in the mTORC1, circadian clock, and AMPK pathways. Identifying mechanistic relationships between intracellular energy, total AA supply, and these pathways in the context of milk protein synthesis in ruminants merits further research.L. Hu was recipient of a 2017 Yangzhou University International Academic Exchange award and a Postgraduate Research & Practice Innovation Program of Jiangsu Province (CX137) to train at University of Illinois. L. Hu and M. Wang were supported by project from Natural Science Foundation of China (31672446). H. Dai and Y. Liang received scholarships from China Scholarship Council (Beijing, China) to undertake PhD training at University of Illinois.Hu, L.; Chen, Y.; Cortes, IM.; Coleman, DN.; Dai, H.; Liang, Y.; Parys, C.... (2020). 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Robust estimation of bacterial cell count from optical density

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[ES] El juego es una herramienta que permite los niños ser capaz de desarrollar sus habilidades tanto físicas como psíquicas sin importar las diversidades sexuales, culturales, raciales y físicas. En cuanto a las ciudades, los parques infantiles juegan un papel importante a día de hoy brindando los lugares seguros y exclusivos para los niños, entre ellos, también muestra la atención creciente hacia la instalación del espacio lúdico accesible. El propósito de esta investigación es mostrar la importancia del juego a lo largo del desarrollo de niños, discutir la cuestión de crear un entorno lúdico accesible para todos los niños, descubrir la situación actual del espacio lúdico entre España y China con respecto a la accesibilidad y al final esperar, a través del proyecto, poder contribuir a concienciar a la sociedad y a los gestores públicos de la necesidad de la accesibilidad universal.[EN] The game is a tool that allows children to be able to develop their physical and psychological abilities regardless of sexual, cultural, racial and physical diversities. As for cities, playgrounds play an important role today providing safe and exclusive places for children, among them, it also shows increasing attention towards the installation of accessible recreational space. The purpose of this research is to show the importance of the game throughout the development of children, to discuss the issue of creating a playful environment accessible to all children, to discover the current situation of the recreational space between Spain and China regarding accessibility and in the end, expect, through the project, to contribute to raising awareness among society and public managers of the need for universal accessibility.Dai, L. (2019). Estudio comparativo sobre la accesibilidad a los espacios lúdicos entre China y España. Universitat Politècnica de València. http://hdl.handle.net/10251/131578TFG

Structure and Capacitance of Electrical Double Layers at the Graphene–Ionic Liquid Interface

Molecular dynamics simulations are carried out to investigate the structure and capacitance of the electrical double layers (EDLs) at the interface of vertically oriented graphene and ionic liquids [EMIM]+/[BF4]−. The distribution and migration of the ions in the EDL on the rough and non-rough electrode surfaces with different charge densities are compared and analyzed, and the effect of the electrode surface morphology on the capacitance of the EDL is clarified. The results suggest that alternate distributions of anions and cations in several consecutive layers are formed in the EDL on the electrode surface. When the electrode is charged, the layers of [BF4]− anions experience more significant migration than those of [EMIM]+ cations. These ion layers can be extended deeper into the bulk electrolyte solution by the stronger interaction of the rough electrode, compared to those on the non-rough electrode surface. The potential energy valley of ions on the neutral electrode surface establishes a potential energy difference to compensate the energy cost of the ion accumulation, and is capable of producing a potential drop across the EDL on the uncharged electrode surface. Due to the greater effective contact area between the ions and electrode, the rough electrode possesses a larger capacitance than the non-rough one. In addition, it is harder for the larger-sized [EMIM]+ cations to accumulate in the narrow grooves on the rough electrode, when compared with the smaller [BF4]−. Consequently, the double-hump-shaped C–V curve (which demonstrates the relationship between differential capacitance and potential drop across the EDL) for the rough electrode is asymmetric, where the capacitance increases more significantly when the electrode is positively charged

Structure and Capacitance of Electrical Double Layers at the Graphene–Ionic Liquid Interface

Molecular dynamics simulations are carried out to investigate the structure and capacitance of the electrical double layers (EDLs) at the interface of vertically oriented graphene and ionic liquids [EMIM]+/[BF4]−. The distribution and migration of the ions in the EDL on the rough and non-rough electrode surfaces with different charge densities are compared and analyzed, and the effect of the electrode surface morphology on the capacitance of the EDL is clarified. The results suggest that alternate distributions of anions and cations in several consecutive layers are formed in the EDL on the electrode surface. When the electrode is charged, the layers of [BF4]− anions experience more significant migration than those of [EMIM]+ cations. These ion layers can be extended deeper into the bulk electrolyte solution by the stronger interaction of the rough electrode, compared to those on the non-rough electrode surface. The potential energy valley of ions on the neutral electrode surface establishes a potential energy difference to compensate the energy cost of the ion accumulation, and is capable of producing a potential drop across the EDL on the uncharged electrode surface. Due to the greater effective contact area between the ions and electrode, the rough electrode possesses a larger capacitance than the non-rough one. In addition, it is harder for the larger-sized [EMIM]+ cations to accumulate in the narrow grooves on the rough electrode, when compared with the smaller [BF4]−. Consequently, the double-hump-shaped C–V curve (which demonstrates the relationship between differential capacitance and potential drop across the EDL) for the rough electrode is asymmetric, where the capacitance increases more significantly when the electrode is positively charged

A CBM development well type optimization method based on the long-run marginal cost

Reasonable optimization of development well type is the prerequisite to realize the economic and effective development of coalbed methane (CBM). However, the existing CBM development well type optimization methods are disadvantageous in many aspects. CBM is a kind of typical unconventional natural gas resource, and its study focuses on single-well evaluation. In this paper, the assessment method and the evaluation index (EI) for CBM development well type optimization based on the long-run marginal cost (LRMC) were constructed on the basis of CBM characteristics from the perspective of economic feasibility. Then, the corresponding decision making criteria were established. Finally, this newly developed method was applied to the well-type optimization of different development blocks in two important CBM development basins in China. And the following research and application results were obtained. First, under the current technical and economic conditions, both directional well and horizontal well are economically feasible to the development of Block A in the Qinshui Basin and Block B in eastern margin of the Ordos Basin, and the economically optimal well type is a horizontal well in Block A and a directional well in Block B. Second, compared with single-well steady daily gas production and single-well investment, the evaluation results on the schemes of different well types present critical value, above which the economic benefit of different schemes are equivalent. Third, EI of different well types is affected by many factors, e.g. geological characteristic of gas reservoirs, single-well production profile, CBM selling price, investment and cost. Therefore, it is necessary to carry out dynamic analysis and update in time based on the change of various influential factors so as to ensure the rationality of decision-making. In conclusion, this newly developed method is intrinsically consistent with traditional evaluation methods, and it is more advantageous with strong operability, intuitive evaluation results and quick and accurate optimization of CBM development well types. Keywords: Coalbed methane (CBM), Long-run marginal cost (LRMC), Development well, Well-type optimization, Directional wells, Horizontal wells, Surface development, Decision making criteria, Critical poin

Optimization analysis of time frequency spectrum enhancement of tunnel blasting vibration signal

Aiming at the problem of insufficient time-frequency resolution of tunnel blasting vibration signal, a time-frequency image enhancement algorithm based on convolutional neural network is applied, through the time-frequency image enhancement of the measured tunnel blasting signal, the aggregation range of the blasting signal energy in the time-frequency domain is captured, and the real signal reflecting the blasting characteristics is reconstructed; according to the real signal, the initiation time of detonator in blasting network is accurately distinguished, and the characteristics of tunnel blasting detonator disaster source are identified.The analysis shows that the time-frequency image enhancement algorithm based on convolutional neural network can effectively suppress the cross-terms in the signal, retain the auto-terms of the signal to the greatest extent, and improve the energy aggregation and time-frequency resolution of the blasting signal; The mixed use of different batches of detonators is the main disaster causing factor of tunnel safety.Supervision should be strengthened to realize safe and efficient tunnel construction

Molecular Dynamics Simulation of Distribution and Diffusion Behaviour of Oil-Water Interfaces

The distribution and diffusion behaviors of microscopic particles at fluorobenzene-water and pentanol-water interfaces are investigated using molecular dynamics simulation. The influences of Na+/Cl- ions and the steric effects of organic molecules are examined. The concentration distributions of different species, the orientations of oil molecules at the interface, and oil-water interface morphology as well as the diffusion behaviors of water molecules are explored and analyzed. The results indicate that a few fluorobenzene molecules move into the water phase influenced by Na+/Cl- ions, while the pentanol molecules at the interface prefer orientating their hydrophilic groups toward the water phase due to their large size. The water molecules more easily burst into the pentanol phase with larger molecular spaces. As the concentration of ions in the water phase increases, more water molecules enter into the pentanol molecules, leading to larger interface roughness and interface thickness. In addition, a lower diffusion coefficient for water molecules at the fluorobenzene-water interface are observed when introducing Na+/Cl- ions in the water phase, while for the pentanol-water system, the mobility of interfacial water molecules are enhanced with less ions and inhibited with more ions

Numerical Analysis of Space Deployable Structure Based on Shape Memory Polymers

Shape memory polymers (SMPs) have been applied in aerospace engineering as deployable space structures. In this work, the coupled finite element method (FEM) was established based on the generalized Maxwell model and the time–temperature equivalence principle (TTEP). The thermodynamic behavior and shape memory effects of a single-arm deployment structure (F-DS) and four-arm deployment structure (F-DS) based on SMPs were analyzed using the coupled FEM. Good consistency was obtained between the experimental data and simulation data for the tensile and S-DS recovery forces, verifying that the coupled FEM can accurately and reliably describe the thermodynamic behavior and shape memory effects of the SMP structure. The step-by-step driving structure is suitable for use as a large-scale deployment structure in space. This coupled FEM provides a new direction for future research on epoxy SMPs