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Objective: To determine the effect of different translocation characteristics on fertilization rate and blastocyst development in chromosomal translocation patients. Methods: This retrospective cohort study was conducted at the Third Affiliated Hospital of Zhengzhou University From January 2017 to December 2022.All couples were diagnosed as reciprocal translocation or Robertsonian translocation by karyotype of peripheral blood lymphocytes test. After adjusting for confounding factors, the effect of chromosomal rearrangement characteristics, such as carrier sex, translocation type, chromosome length and break sites, on fertilization rate and embryo development were analysed separately using multiple linear regression. Results: In cases of Robertsonian translocation (RobT), the carrier sex plays an independent role in fertilization rate, and the male carriers was lower than that of female carriers (76.16% vs.86.26%, P = 0.009). In reciprocal translocation (RecT), the carrier sex, chromosome types and break sites had no influence on fertilization rate, blastocyst formation rate (P > 0.05). However, patients with human longer chromosomal (chromosomes 1–5) translocation have a lower available blastocyst formation rate (Group AB vs. Group CD: 41.49%vs.46.01%, P = 0.027). For male carriers, the translocation types was an independent factor affecting the fertilization rate, and the RobT was the negative one (B = − 0.075, P = 0 0.009). In female carriers, we did not observe this difference (P = 0.227). Conclusions: In patients with chromosomal translocation, the fertilization rate may be influenced by carrier sex and translocation type, chromosomes 1–5 translocation may adversely affect the formation of available blastocysts. Break sites have no role in fertilization and blastocyst development. [ABSTRACT FROM AUTHOR]

In this study, we comprehensively investigate the structure and operational principles of the Rotary Direct Drive Electro-Hydraulic Pressure Servo Valve (RDDPV). Our objective is to establish the dynamics equations governing the motor, slide valve, and bias mechanism of the valve. Additionally, we construct a mathematical model for the servo valve controller, while ensuring the linearization of the controller model. Furthermore, we conduct an in-depth analysis of the static characteristics of the valve, including linearity, dead zone, hysteresis loop, and zero drift. Regarding the dynamic characteristics, we establish a dynamic mathematical model for the RDDPV valve. Subsequently, we subject the servo valve to analysis with a focus on frequency response and dynamic response, using the control current as the input and the pressure as the output. To perform these analyses, we employ the software package SIMULINK of MATLAB, facilitating dynamic simulations. Remarkably, the simulation results exhibit the valve's conformity to design requirements, underscoring its suitability for subsequent research and development endeavors. Through our rigorous investigation, we offer essential technical support for the forthcoming stages of the valve's research and development, thereby laying a robust foundation for its further advancement. [ABSTRACT FROM AUTHOR]

• Identification for compounds alleviating extracellular matrix stiffness. • Echinatin upregulates the expression of glutamate cysteine ligases. • Echinatin maintains glutathione homeostasis to inhibit the ferroptotic cell death. • Echinatin has therapeutic effects against arterial stiffening and atherosclerosis. Decreased vascular compliance of the large arteries as indicated by increased pulse wave velocity is shown to be associated with atherosclerosis and the related cardiovascular events. The positive correlation between arterial stiffening and disease progression derives a hypothesis that softening the arterial wall may protect against atherosclerosis, despite that the mechanisms controlling the cellular pathological changes in disease progression remain unknown. Here, we established a mechanical-property-based screening to look for compounds alleviating the arterial wall stiffness through their actions on the interaction between vascular smooth muscle cells (VSMCs) and the wall extracellular matrix (ECM). We found that echinatin, a chalcone preferentially accumulated in roots and rhizomes of licorice (Glycyrrhiza inflata), reduced the stiffness of ECM surrounding cultured VSMCs. We examined the potential beneficial effects of echinatin on mitigating arterial stiffening and atherosclerosis, and explored the mechanistic basis by which the compound exert the effects. Administration of echinatin in mice fed on an adenine diet and in hyperlipidemia mice subjected to 5/6 nephrectomy mitigated arterial stiffening and atherosclerosis. Mechanistic insights were gained from the RNA-sequencing results showing that echinatin upregulated the expression of glutamate cysteine ligases (GCLs), both the catalytic (GCLC) and modulatory (GCLM) subunits. Further study indicated that upregulation of GCLC/GCLM in VSMCs by echinatin maintains the homeostasis of glutathione (GSH) metabolism; adequate availability of GSH is critical for counteracting arterial stiffening. As a consequence of regulating the GSH synthesis, echinatin inhibits ferroptosis and matrix remodeling that being considered two contributors of arterial stiffening and atherosclerosis. These data demonstrate a pivotal role of GSH dysregulation in damaging the proper VSMC-ECM interaction and uncover a beneficial activity of echinatin in preventing vascular diseases. [ABSTRACT FROM AUTHOR]

For manipulating heat flow according to human desire, thermal metamaterial structures (meta-structures) have attracted growing interest. Based on the transformation thermotics and the effective medium approximation theory, we designed and fabricated a convertible thermal meta-structural device to demonstrate that multiple different heat-flow manipulations could be conducted using a single thermal meta-structural device. The convertible meta-structures were designed by discretizing a two-dimensional plane and separating multiple square unit modules with stripe-shaped dissimilar materials of the Polydimethylsiloxane (PDMS) and solid resin with surface metallized copper (Cu). The convertible thermal meta-structure device with a relatively high geometric accuracy was fabricated via a proposed hybrid manufacturing path of "Stereolithography Apparatus (SLA) 3D printing—electroless plating—electroplating—thermally insulated packaging". The thermal manipulation features were numerically simulated and preliminarily verified by experimental testing. Using multiple dispersed square unit modules to replace an annular region of the thermal meta-structure exhibited different thermal flow functions, including thermal cloak, thermal concentration, thermal rotation, and thermal dispersion, through the unique geometric design of the heat-flow transfer direction within each module. By rotating each square unit module at a specific angle and arranging the modules, similar to a "jigsaw puzzle", the convertibility among different thermal manipulation functions was achieved. This path is anticipated to provide a new strategy for multifunctional meta-structures in thermo-physics and its potential engineering applications. [ABSTRACT FROM AUTHOR]

The equiatomic CoCrFeNiMn high-entropy alloy (HEA) possesses excellent properties including exceptional strength–ductility synergy, high corrosion resistance, and good thermal stability. Selective laser melting (SLM) additive manufacturing facilitates the convenient fabrication of the CoCrFeNiMn HEA parts with complex geometries. Here, the SLM process optimization was conducted to achieve a high relative density of as-built CoCrFeNiMn HEA bulks. The mechanisms of process-induced defects and process control were elucidated. The microscale mechanical behaviors were analyzed through in situ scanning electron microscopy observation during the compression tests on micro-pillars of the as-built HEA. The stress–strain characteristics by repeated slip and mechanism of "dislocation avalanche" during the compression of micro-pillars were discussed. The high-cycle fatigue tests of the as-built HEA were performed. It was found that a large number of nano-twins were induced by the fatigue, causing a non-negligible cycle softening phenomenon. The effects of promoted ductility due to the fatigue-induced nano-twins were illustrated. This work has some significance for the engineering application of the SLM additively manufactured CoCrFeNiMn HEA parts. [ABSTRACT FROM AUTHOR]

-Many researchers have investigated the optimal energy scheduling to meet the demand regarding sustainable development issues and the economic and technical indices. This study presents the day-ahead operation of a smart residential distribution electrical grid as a bi-stage-multiple-criteria decision-making modeling. The proposed energy optimization is implemented based on optimal demand management in upper-stage and multiple-criteria decision-making in lower-stage. The multiple-criteria problem is modeled from the viewpoint of the grid's operator to optimize energy consumption costs, power losses and demand side comfort. The optimal demand management in upper-stage is coordinated considering price traffic in the upstream grid. The load shifting approach and load interruption approach are presented as optimal demand management for residential consumers. The operation of demand management by using load shifting and load interruption approaches is done via deferrable loads and clippable loads in smart residential homes, respectively. The proposed energy optimization in both stages by improved sunflower optimization (IFSO) is handled, and the TOPSIS method is proposed for the best trade-off of the multiple-criteria decision-making. The day-ahead energy operation is applied on the 33-bus distribution network to investigate the effectiveness of the residential distribution electrical grid considering obtained results from mathematical modeling and demand management approaches. • A bi-stage-multiple-criteria decision-making modeling for energy consumption costs, power losses, and demand side comfort in smart residential distribution electrical grid is proposed. • The load-shifting and load-interruption approaches are proposed to demand-side optimization considering price traffics. • The IFSO algorithm and the TOPSIS approach for the multiple-criteria decision-making process are proposed for solving problem. [ABSTRACT FROM AUTHOR]

Ion transport under nanoconfined spaces is a ubiquitous phenomenon in nature and plays an important role in the energy conversion and signal transduction processes of both biological and artificial systems. Unlike the free diffusion in continuum media, anomalous behaviors of ions are often observed in nanostructured systems, which is governed by the complex interplay between various interfacial interactions. Conventionally, nanoionics mainly refers to the study of ion transport in solid‐state nanosystems. In this review, to extent this concept is proposed and a new framework to understand the phenomena, mechanism, methodology, and application associated with ion transport at the nanoscale is put forward. Specifically, here nanoionics is summarized into three categories, i.e., biological, artificial, and hybrid, and discussed the characteristics of each system. Compared with nanoelectronics, nanoionics is an emerging research field with many theoretical and practical challenges. With this forward‐looking perspective, it is hoped that nanoionics can attract increasing attention and find wide range of applications as nanoelectronics. [ABSTRACT FROM AUTHOR]

The biped robot adopts the human movement mode. Compared with other movement modes, the gait has good flexibility and adaptability. It is very important in the research of robotics, so it has become a hot spot of robotics research. This article aims to study the application of neural networks in the stability of biped robots and the embedded control of walking mode. A method of establishing precise mathematical modeling and stability analysis is proposed. Based on this model, the motion characteristics of the biped robot's walking mode and the local stability of joints are studied, and the motion mode of passive walking under the control of the neural network is deeply analyzed, using a neural network to control the stability of biped robot motion and adopting the research method of the embedded control system in walking mode. Essentially, the output value of the physical network is used to judge whether the robot is in a stable position so as to perform appropriate actions and control the robot's stability of walking. The experimental results show that the biped robot can detect movement and overcome obstacles through related networks and embedded control systems. Through the control of the embedded system, the errors of each joint of the biped robot on flat ground, stairs, and obstacles are greatly reduced. The most obvious reduction of the deviation is that the ankle joint decreases from 2.5 to 0.07 when rotating, and the knee joint angle deviation is reduced from 3.8 to 2, which greatly improves the stability of the biped robot's walking mode. [ABSTRACT FROM AUTHOR]

Aqueous multiphase systems have attracted a lot of interest recently espeically due to target applications in the biomedical field, cosmetics, and food. In turn, water‐in‐water Pickering emulsions are investigated frequently. In here, graphitic carbon nitride (g‐CN) stabilized water‐in‐water Pickering emulsions are fabricated via the dextran and poly(ethylene glycol)‐based aqueous two‐phase system. Five different derivatives of g‐CN as the Pickering stabilizer are described and the effect of g‐CN concentration on droplet sizes is investigated. Stable emulsions (up to 16 weeks) are obtained that can be broken on purpose via various approaches, including dilution, surfactant addition, and most notably light irradiation. The novel approach of water‐in‐water emulsion stabilization via g‐CN opens up considerable advances in aqueous multiphase systems and may also introduce photocatalytic properties. [ABSTRACT FROM AUTHOR]

In this paper, the selective laser melting (SLM) forming method was combined with the requirement of boiling heat transfer for porous structure to study the forming process and boiling heat transfer characteristics of porous structure of G-surface lattice formed by SLM. 316L stainless steel powder was used to rasterize the G-surface structure. Besides, porosity and surface morphology of G-surface lattice were analyzed. Deionized water was used for boiling heat transfer experiment to study the effect of technological parameters on boiling heat transfer enhancement. On this basis, the bubble escape modes in different stages of boiling heat transfer of G-surface lattice were considered, and the delay of the critical heat flux caused by G-surface lattice was explained. This study provides a useful reference for the design of lattice heat cooling structure. [ABSTRACT FROM AUTHOR]

Purpose: This study investigated the safety and effectiveness of oocyte vitrification by comparing the clinical pregnancy and perinatal outcomes between transfer cycles of vitrified oocytes and those of vitrified embryos. Methods: A retrospective cohort study was conducted to analyze the clinical data of patients who underwent cleavage-stage embryo transfer at the Department of Reproductive Medicine between January 2011 and June 2021. Seventy-seven transfer cycles of fresh cleavage-stage embryos developed from vitrified-thawed oocytes (oocyte vitrification group) and 2170 transfer cycles of vitrified-thawed cleavage-stage embryos developed from fresh oocytes (embryo vitrification group) were included. Further, 293 cases were selected from the embryo vitrification group after applying propensity score matching at 1:4. The primary outcomes were miscarriage rate, live birth rate, and neonatal birth weight. Results: No statistically significant differences were observed in the baseline data, pregnancy, perinatal outcomes, or neonatal outcomes for either singleton or twin births between the two groups after matching. Backwards stepwise regression was used to analyze the length of gestation. The age of female participants (β = − 0.410, 95% CI = − 1.339 ~ − 0.620, P < 0.001) had a statistically significant effect. Conclusion: Oocyte vitrification results in similar clinical pregnancy and perinatal outcomes as does embryo vitrification; hence, it is a relatively safe assisted reproductive technique. [ABSTRACT FROM AUTHOR]

Phase change materials (PCMs) lie at the heart for energy storage technology. In this paper, we proposed a porous media based composite PCM, consisting of Heptadecane (C 17 H 36 ) as the core and mesoporous silica (MCM-41) as the shell. Basing on the nanostructures we built and verified, the thermal properties of composite were predicted by molecular dynamics (MD) method, including the melting point, latent heat, specific heat capacity and thermal conductivity. Furthermore, the effects of the filling ratio of C 17 H 36 , the pore size or porosity of MCM-41 and the temperature were analyzed. It turns out that the composite C 17 H 36 /MCM-41 obtains at least 2-fold increase over bulk C 17 H 36 in the thermal conductivity, due to the introduction of supporting material MCM-41. Owning to the size effect of C 17 H 36 filling in nanopores, both the melting point and latent heat of composite are always lower than bulk values of C 17 H 36 , while the specific heat capacity of composite is between values of bulk C 17 H 36 and silica film. The specific heat capacity and thermal conductivity increases with rising temperature. The properties of composite are controllable by tailoring the pore size of supporting material or/and filling ratio of core in the pore. The melting point, latent heat and specific heat capacity would rise with the increase of pore size or/and filling ratio. With respect to the thermal conductivity of composite, it drops when the pore size enlarges or the porosity increases while keeping constant filling ratio; while it first rises almost linearly with the increase of core filling ratio, and then keeps stable after the filling ratio reaches 70%. In addition, increasing filling ratio is more effective than enlarging pore size in improving the latent heat, specific heat capacity and thermal conductivity. On the contrary, the melting point is more sensitive to the change in pore size rather than filling ratio, and it is linearly dependent on the inverse pore size. This work is expected to be helpful in providing some fundamental data for the design of porous media based PCM. [ABSTRACT FROM AUTHOR]

Inhibition of phosphodiesterase-4 or 5 (PDE4 or PDE5) increases cyclic adenosine monophosphate (cAMP)- or cyclic guanosine monophosphate (cGMP), respectively, which activates cAMP response element-binding protein (CREB)/brain-derived neurotrophic factor (BDNF)/neuropeptide VGF (non-acryonimic) signaling and produces antidepressant-like effects on behavior. However, causal links among these actions have not been established. In the present study, mice were evaluated for the effects of etazolate and sildenafil, the inhibitor of PDE4 or PDE5, respectively, on depressive-like behavior induced by chronic unpredictable mild stress (CUMS) in the forced-swimming test (FST) and tail suspension test (TST), in the presence or absence of the inhibitor of protein kinase A (PKA) or protein kinase G (PKG) via intracerebroventricular (i.c.v.) infusions. The levels of cAMP, cGMP and expression of pCREB, CREB, BDNF and VGF in both the hippocampus and prefrontal cortex were determined. The results showed that etazolate at 5.0 mg/kg or sildenafil at 30 mg/kg significantly reversed CUMS-induced depressive-like behavior; the effects were paralleled with the increased levels of cAMP/pCREB/BDNF/VGF or cGMP/pCREB/BDNF/VGF signaling, respectively. These effects were completely abolished following inhibition of PKA or PKG, respectively. The results suggest that inhibition of PDE4 by etazolate or PDE5 by sildenafil produced antidepressant-like effects in CUMS-treated animals via cAMP or cGMP signaling, which shares the common downstream signal pathway of CREB/BDNF/VGF. [ABSTRACT FROM AUTHOR]

A correction to this paper has been published: https://doi.org/10.1007/s11051-021-05232-2 [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) have attracted increasing attention for their function in oocyte in vitro maturation (IVM). In this study, we aimed to explore the functional role and underlying mechanism of miR-375 in oocyte IVM. Cumulus-oocyte complexes (COCs) were cultured in standard cell culture conditions until they reach metaphase II (MII) stage. MiR-375 overexpression or knockdown was achieved by corresponding lentiviral transduction. Levels of miR-375, disintegrin and metalloproteinase with thrombospondin-like motifs 1 (ADAMTS1) mRNA and progesterone receptor (PGR) mRNA were detected by qRT-PCR. Western blotting was used to assess the expression of ADAMTS1 and PGR protein. The targeted interaction between miR-375 and ADAMTS1 or PGR was verified by dual-luciferase reporter assay and RNA immunoprecipitation assay. Our results demonstrate that miR-375 is downregulated, and ADAMTS1 and PGR are upregulated in cumulus cells during COC maturation. MiR-375 negatively regulates COC maturation. Moreover, ADAMTS1 and PGR are two targets of miR-375 in cumulus cells. ADAMTS1 or PGR knockdown represses COC maturation and miR-375 inhibits the expression levels of ADAMTS1 and PGR in cumulus cells. Additionally, miR-375 overexpression-mediated suppressive effect on COC maturation is abated by ADAMTS1 or PGR expression restoration. In conclusion, our study suggests that miR-375 represses oocyte IVM at least partially through targeting ADAMTS1 and PGR in cumulus cells, providing a novel insight for the involvement and underlying mechanism of miR-375 in oocyte IVM. [ABSTRACT FROM AUTHOR]

• The proposed AP-GAN-DNN method is able to predict creep fracture life more accurately in the case of small samples, which solves the complex nonlinear problem and the problem of test data dispersion. • Compared with traditional physical methods and machine learning models, the AP-GAN-DNN model has better generalization and robustness for creep fracture life prediction. • AP-GAN data enhancement method can significantly reduce the "pattern collapse" effect of GAN and improve the performance of prediction algorithms. 7050 aluminum alloy has high strength and excellent fracture toughness. However, damage can be caused to the 7050 aluminum alloy by creep at elevated temperatures. The accuracy of conventional creep life prediction methods may fall short of meeting the desired standards. And the application of machine learning (ML) methods is limited due to the scarcity and dispersion of creep sample data. Generative Adversarial Networks (GAN) are often used for data enhancement, but suffer from "pattern collapse" under small sample conditions. To solve the above problems, this paper proposes a creep fracture life prediction method, which combines the affinity propagation (AP) clustering algorithm, GAN, and deep neural networks (DNN) for accurate creep fracture life prediction. The AP clustering algorithm for adaptive clustering was utilized to better reflect the creep sample distribution. Independent GAN models were trained for each cluster to better capture distribution characteristics of the data and generate synthetic data that was highly similar to the real data. The DNN models were trained using the synthetic data and then predicted using real creep fracture life data. The presented method was compared with traditional physical and machine learning methods, and the method combining K-Means, GAN, and DNN. The experimental results show that the method proposed in this paper has better prediction accuracy in a small sample creep fracture life dataset. [ABSTRACT FROM AUTHOR]

The electrochemical CO2 reduction reaction (eCO2RR) to multicarbon products has been widely recognized for Cu‐based catalysts. However, the structural changes in Cu‐based catalysts during the eCO2RR pose challenges to achieving an in‐depth understanding of the structure–activity relationship, thereby limiting catalyst development. Herein, we employ constant‐potential density functional theory calculations to investigate the sintering process of Cu single atoms of Cu−N−C single‐atom catalysts into clusters under eCO2RR conditions. Systematic constant‐potential ab initio molecular dynamics simulations revealed that the leaching of Cu−(CO)x moieties and subsequent agglomeration into clusters can be facilitated by synergistic adsorption of H and eCO2RR intermediates (e.g. CO). Increasing the Cu2+ concentration or the applied potential can efficiently suppress Cu sintering. Both microkinetic simulations and experimental results further confirm that sintered Cu clusters play a crucial role in generating C2 products. These findings provide significant insights into the dynamic evolution of Cu‐based catalysts and the origin of their activity toward C2 products during the eCO2RR. [ABSTRACT FROM AUTHOR]

The electrochemical CO2 reduction reaction (eCO2RR) to multicarbon products has been widely recognized for Cu‐based catalysts. However, the structural changes in Cu‐based catalysts during the eCO2RR pose challenges to achieving an in‐depth understanding of the structure–activity relationship, thereby limiting catalyst development. Herein, we employ constant‐potential density functional theory calculations to investigate the sintering process of Cu single atoms of Cu−N−C single‐atom catalysts into clusters under eCO2RR conditions. Systematic constant‐potential ab initio molecular dynamics simulations revealed that the leaching of Cu−(CO)x moieties and subsequent agglomeration into clusters can be facilitated by synergistic adsorption of H and eCO2RR intermediates (e.g. CO). Increasing the Cu2+ concentration or the applied potential can efficiently suppress Cu sintering. Both microkinetic simulations and experimental results further confirm that sintered Cu clusters play a crucial role in generating C2 products. These findings provide significant insights into the dynamic evolution of Cu‐based catalysts and the origin of their activity toward C2 products during the eCO2RR. [ABSTRACT FROM AUTHOR]

[Display omitted] • The under-coordinated dual-atom sites in CeO 2 enable selective CO 2 to CO conversion. • A lower barrier is found for dissociating C–O over the dual-atom sites than CeO 2. • The active dual-atom sites in CeO 2 prevent carbon deposition. • CO 2 is effectively activated in the form of carbonate species on dual-atom sites. • The dual-atom sites have shown good stability at 823 K. Stable CO 2 electrolysis to CO and O 2 in solid-oxide electrochemical cells (SOCs) is challenging due to the competitive carbon deposition. CeO 2 -based electrodes have shown advanced carbon-tolerant ability in SOCs. Here, by conducting density-functional theory calculations, we report highly selective CO 2 to CO conversion catalyzed by a novel dual-atom site in CeO 2 induced by substituting one Ce with two Pd (Ni or Cu). CO 2 is effectively activated in the form of carbonate species (CO 2 * O) with oxygen strongly adsorbed by the under-coordinated dual-atom site, which then dissociates C–O bond with a 1.00 eV lower barrier compared to clean CeO 2. By contrast, a 0.22 eV larger barrier is found for carbon deposition on dual-atom sites than on CeO 2 , leading to carbon suppression over dual-atom sites. Therefore, 2Pd (2Ni or 2Cu) dual-atom sites in CeO 2 can significantly improve kinetics of CO 2 reduction into CO because of the crucial role of their under-coordinated local structure in facilitating CO 2 activation while preventing carbon deposition during CO 2 electrolysis, which sheds light on rational design of dual-atom active sites in metal oxide catalysts. [ABSTRACT FROM AUTHOR]

Aiming at laser powder bed fusion of GH3536 nickel base alloy, the effects of different scanning strategies on microstructure, porosity and mechanical properties were explored. In the aspect of microstructure and micro hardness of the sample, three scanning strategies had little difference; in the aspect of macro mechanical properties of the sample, the slope subarea scanning was better than the helix and island scanning. On this basis, the slope subarea scanning was selected as the optimal scanning strategy to form the G-surface structure, and the compression performance of G-surface was studied. The results showed that: (1) the compression performance of G-surface structure was smaller than that of solid structure, The compression strength of G-surface can only reach about 20% of solid structure: the average strength value of G-surface is 220 MPa, solid structure is 1.1 GMpa; while G-surface structure had a smooth compression curve, which indicated the good energy absorption characteristics; (2) with the increase of wall thickness, the mechanical performance of G-surface structure was also enhanced, while the energy absorption capacity was constantly reduced; (3) with the same wall thickness, the compression performance of sample in building direction (BD) is higher than that in horizontal direction (HD). [ABSTRACT FROM AUTHOR]

Urea synthesis from abundant CO2 and N‐feedstocks via renewable electricity has attracted increasing interests, offering a promising alternative to the industrial‐applied Haber‐Meiser process. However, the studies toward electrochemical urea production remain scarce and appeal for more research. Herein, in this perspective, an up‐to‐date overview on the urea electrosynthesis is highlighted and summarized. Firstly, the reaction pathways of urea formation through various feedstocks are comprehensively discussed. Then, we focus on the strategies of materials design to improve C−N coupling efficiency by identifying the descriptor and understanding the reaction mechanism. Finally, the current challenges and disadvantages in this field are reviewed and some future development directions of electrocatalytic urea synthesis are also prospected. This Minireview aims to promote future investigations of the electrochemical urea synthesis. [ABSTRACT FROM AUTHOR]

[Display omitted] • Substitution of Cu 3 or Cu 4 clusters for one Ce atom accounts for the experimentally observed vibrational peaks of the adsorbed CO, rather than the Cu single atom or dimer. • Cu single-atom and Cu n clusters (n = 2–4) doped into CeO 2 all exhibit an excellent stability against ripening and a promising catalytic activity for low-temperature CO oxidation. Identifying the local environments of active sites of Cu x Ce 1-x O 2 solid solution for low-temperature CO oxidation remains significant challenges. In this study, we coupled density functional theory and microkinetic modeling to thoroughly investigate local structures of Cu x Ce 1-x O 2 solid solution catalysts, as well as its catalytic performance for low-temperature CO oxidation. Combined with the infrared spectra simulations, we propose that the substitution of Cu 3 or Cu 4 clusters for one Ce atom accounts for the experimentally observed vibrational peaks of the adsorbed CO, rather than the Cu single atom or dimer. Cu single-atom and Cu n clusters (n = 2–4) doped into CeO 2 all exhibit an excellent stability against ripening and a promising catalytic activity for low-temperature CO oxidation. This research for the first time elucidates the nature of Cu x Ce 1-x O 2 solid solution catalysts and paves the way for the rational design of Cu/CeO 2 catalysts for CO oxidation. [ABSTRACT FROM AUTHOR]

Von Willebrand Factor (VWF) can promote platelet adhesion to the post-atherosclerotic regions to initiate thrombosis. The synthesis and secretion of VWF are important functions of endothelial cells (ECs). However, the mechanism through which blood flow regulates endothelial secretion of VWF remains unclear. We utilized a parallel-plate flow apparatus to apply fluid shear stress to human umbilical vein endothelial cells (HUVECs). Compared with pulsatile shear stress that mimics laminar flow in the straight parts of arteries or upstream of atherosclerotic stenosis sites, short-term exposure to oscillatory shear stress (OS) that mimics disturbed flow increased VWF secretion independent of affecting synaptosomal-associated protein 23 (SNAP23) expression and promoted the translocation of SNAP23 to the cell membrane. Vimentin associated with SNAP23, and this association was enhanced by OS or histamine. Acrylamide, a reagent that disrupts vimentin intermediate filaments, prevented histamine/OS-induced SNAP23 translocation, as well as VWF secretion. Immunofluorescence analysis revealed that the polarity of the vimentin intermediate filament network decreased after stimulation with histamine or OS. In addition, inhibition of protein kinase A (PKA) or G protein coupled receptor 68 (GPR68) eliminated the histamine/OS-induced phosphorylation of vimentin at Ser38 and secretion of VWF. Furthermore, syntaxin 7 might assist with the translocation of SNAP23 to the cell membrane, thus playing a role in promoting VWF secretion. The GPR68/PKA/vimentin signaling pathway may represent a novel mechanism for the regulation of SNAP23-mediated VWF secretion by ECs under OS and provide strategies for the prevention of atherosclerosis-related thrombosis. • Explore new mechanism through which blood flow regulates endothelial VWF secretion. • Short OS promotes VWF secretion through vimentin-associated translocation of SNAP23. • Syntaxin 7 interacts with vimentin to mediate the transport of SNAP23. • The GPR68/PKA/vimentin pathway involved in shear stress-induced VWF secretion. [ABSTRACT FROM AUTHOR]

Microchannel structures possess high efficiency and high boiling heat transfer coefficient of two-phase flow. In particular, the grid structure has the advantages of a simple pattern, large load capacity, and good surface adaptability. Employing the laser-based powder bed fusion (L-PBF) manufacturing technology, a new method of forming heat transfer grids with a controllable structure is proposed in this study. The formation principle, process, and the reasons for improvements in the boiling heat transfer performance were investigated with stainless steel materials. Laser scanning with varying scan spacings was used to prepare multiple structures with different grid widths and wall heights. On this basis, the porosity and pore morphology of the grid structures were analyzed, followed by pool boiling heat transfer experiments. The results revealed that the grid structure significantly affected the nucleate boiling behavior and increased the critical heat flux (CHF). It was found that the 0.5 mm sample exhibited optimum critical heat transfer performance, with an improvement of 10–27% compared to those of the other four samples (minimum of 63.3 W·cm−2 and maximum of 93.9 W·cm−2). In addition, for samples with a grid width greater than 0.5 mm, the boiling slightly decreased by <5%. When the grid width was further increased, the flow resistance effect and the bubble synapse generation effect tended to converge. In these cases, boiling heat transfer only occurred in a single phase along the direction of the medium wall thickness, thus failing to achieve two-phase heat transfer through bubble growth and collapse. [ABSTRACT FROM AUTHOR]

Poly (ether sulfone) (PES), as a kind of special engineering plastic, is widely used in the field of separation. However, its gas separation performance is unremarkable. Therefore, a series of PES containing the tetraphenyl bipyrimidine unit (PES-TPhbpy-x) was prepared by nucleophilic polycondensation to improve the gas separation performance of PES. PES-TPhbpy-x exhibited a high molecular weight, excellent mechanical properties, and could form robust membranes. With increasing TPhbpy unit content in PES-TPhbpy-x, the glass transition temperature and heat resistance increased. WAXD analysis revealed that the d -spacing of PES-TPhbpy-x is larger than that of PES. This indicated that the TPhbpy unit could hinder the polymer chain packing and enhance the rigidness of the polymers. Compared with PES, PES-TPhbpy-x exhibited an excellent gas separation performance. The CO 2 permeability of the PES-TPhbpy-100 increased by 570%, and the CO 2 /N 2 selectivity and CO 2 /CH 4 selectivity increased by 49% and 50%, respectively. Moreover, PES-TPhbpy-100 could form a membrane by the hot-press method. The CO 2 permeability of the PES-TPhbpy-100 membrane prepared by the hot-press method was 12.81 barrer. In addition, the CO 2 /N 2 and CO 2 /CH 4 selectivities were 32.0 and 37.7, which were 27% and 35% higher than those of the PES membrane, respectively. Image 1 • A novel bisphenol containing tetraphenyl bipyrimidine structure was prepared. • PES-TPhbpy-100 could processed by environment-friendly hot-press method. • PES-TPhbpy-x owned the best gas separation performance among analogous polymers. [ABSTRACT FROM AUTHOR]

Abstract Selective Laser Melting (SLM) was applied to Additive Manufacturing (AM) of carbide ceramic particulate reinforced 316 L stainless steel matrix composites. The dense and ultrafine-grained Austenite matrix with uniformly distributed and nano-sized VC x particulate reinforcements were obtained according to the tailored SLM process parameters and 3 wt% submicron-sized V 8 C 7 ceramic particle addition into 97 wt% 316 L powder via ball-milling treatment. The influences of SLM process parameters on the SLM printed composites in terms of density, surface roughness, phase constitution, microstructure characteristics and mechanical tensile performance were investigated in detail, comparing with the SLM printed 316 L in absence of vanadium carbides. Based on the electron back-scattered diffraction analyses, the number of grains with grain size less than 2 µm accounted for more than 90% in the printed composites. The formation mechanisms of the printed composites with their unique microstructure characteristics were elaborated. The room-temperature ultimate tensile strength of the printed 316 L matrix composites achieved higher than 1400 MPa, which was more than twice as high as that of printed 316 L stainless steel. It contributed substantially to the strengthening effect on the printed composites of the ultrafast laser-induced and highly nonequilibrium melting-solidification nature of SLM process, the dispersed carbide ceramic particulate reinforcements, the nanoscaled nucleation sites of VC x for the equiaxed Austenite grains, and the inhibition against Austenite matrix growth by particulate dispersedly distributed along Austenite grain boundaries. [ABSTRACT FROM AUTHOR]

There is no consensus regimen for the optimal endometrial preparation for cryopreservation and vitrified-thawed embryo transfer cycles. This is largely caused by the lack of sufficient investigation and analyses on the respective pregnancy and perinatal outcomes by different regimens. This study aimed to compare both pregnancy and perinatal outcomes between the modified natural and artificial cycles in vitrified-thawed day three embryo transfer for women with regular menstruation. A total of 1,482 vitrified-thawed day three embryo transfer cycles were reviewed including 427 modified natural cycles (NC), 132 ovulation induction cycles (OC), 794 artificial cycles (AC), and 129 GnRH agonist artificial cycles (GAC). The primary outcome that was evaluated was live birth rate. The NC regimen demonstrated a higher rate of ongoing pregnancy (43.8% vs. 30.2%,P= 0.002) and a lower rate of late abortion (2.8% vs. 14.0%,P= 0.003) than the GAC regimen as well as a higher implantation rate (31.9% vs. 27.1%,P= 0.008) and live birth rate (43.1% vs. 34.1%,P= 0.002) than the AC regimen. A significantly higher peak endometrial thickness before transfer was observed in patients using the NC and GAC regimens (10.0 ± 1.7, 9.9 ± 2.4) compared to the AC regimens (9.2 ± 1.5,P= 0.000). Multivariate logistic regression showed that the NC protocol was associated with a higher live birth rate. There were no significant differences in rates of pregnancy complications, neonatal mortality, birth defects, mean birth weight, and other perinatal outcomes among the regimens. Modified natural cycle endometrial preparation regimen for vitrified-thawed day three embryo transfer is associated with superior live birth pregnancy outcomes compared to artificial cycles. Future studies are warranted to investigate the underlying biologic mechanisms of these findings. AbbreviationsART: assisted reproductive technology; BMI: body mass index; FET: frozen-thawed embryo transfer; HCG: human chorionic gonadotropin; IVF:in-vitrofertilization; IVF-ET:in-vitrofertilization and embryo transfer; OHSS: ovarian hyperstimulation syndrome; RCTs: randomized controlled trials [ABSTRACT FROM PUBLISHER]

• Combination of CaO2 and magnetite was applied firstly in anaerobic digestion. • Combination of CaO2 and magnetite strongly improved the digestive performance. • CaO2 and magnetite had synergistic effects on organic matter transformation. • Microbial metabolism promotion was revealed from metagenomics. Optimizing methane production from food waste (FW) efficiently is always a hot topic in the field of anaerobic digestion (AD). In this study we aimed to improve the conversion of organics to methane by using CaO 2 and magnetite to enhance the semi-continuous AD of food waste. Under the organic load of 2.5 g VS/L·d−1, the specific methane yield was increased from 333.9 mL CH 4 /g·VS to 423.4 mL CH 4 /g·VS by adding 0.01 g/L CaO 2 with 0.4 g/L magnetite, improving the production of methane from FW. We assessed reactor performance, ORP changes, mass balance, enzyme activities and characterized the metagenomic profile of microorganisms involved in digestion. These microorganisms showed rapid conversion of volatile fatty acids and increased expression of genes related to hydrolysis and acid production. Thus, the addition of CaO 2 and magnetite optimized the relationship between fermentation bacteria and methanogenic archaea to enhance the overall production of methane. Microorganisms evolved unique adaptive mechanisms in the co-operative environment of CaO 2 and magnetite, as their energy metabolism patterns combined those controlled by individual CaO 2 and magnetite addition. This method of combining a micro-aeration environment with conductive materials provides a new perspective for optimizing the AD of FW. [Display omitted] [ABSTRACT FROM AUTHOR]

This article proposes a novel nonlinear state estimation framework for humanoid robots based on the dynamics of the center of mass (CoM) and dual-loop Kalman filter(DLKF). It effectively fuses the information from inertial measurement unit(IMU), joint encoders, and foot sensitive resistors (FSRs), and provides state estimates for various gait generation algorithms and dynamic balance controllers with CoM or divergence component of motion (DCM) feedback. Compared to the widely used linear models such as the linear inverted pendulum model (LIPM), the nonlinear dynamics of CoM effectively reduce the process error. However, the humanoid robot is a highly complex dynamic system with multiple links and joints, the dynamics of CoM are also a simplification of the whole body dynamics. As a result, it brings non-zero-mean, non-Gaussian, and correlated process error, which the conventional extend Kalman filter (EKF) cannot handle. To this end, the DLKF is adopted to compensate the process error, thus the estimator is robust to the modeling error caused by simplifications. Furthermore, the invariant extended Kalman filter (IEKF) is used for floating base kinematics estimation, and the force/torque (F/T) sensor which is difficult to integrate on smaller or cheaper robots due to the size and cost is not used in our framework. Finally, our nonlinear state estimation framework improves the accuracy of CoM and DCM estimation in a virtual environment simulation using our self-developed Defensor hydraulic humanoid robot. • Humanoid robots are complex multi-body dynamic systems. • The simplification of whole body dynamics brings process model error. • The dual loop Kalman filter is utilized to compensate the process model error. • A nonlinear state estimation framework for humanoid robots is suggested. [ABSTRACT FROM AUTHOR]

A microchannel radiator is advantageous due to its high efficiency and large boiling heat transfer coefficient of two-phase flow. Based on the research of uniform lattice structures, this study proposed a microchannel heat exchanger with a nonuniform lattice structure. The calculation, optimal formation, and boiling heat transfer performance of the nonuniform lattice structure based on selective laser melting (SLM) were investigated, and heat exchange samples were successfully prepared using SLM. The porosity and pore morphology of the samples were analysed, and the contrast experiments of boiling heat transfer were conducted with deionised water. The results revealed that the heat flow density of the lattice structure was a minimum of 244% higher than that of the traditional liquid-cooled plate. The critical heat flux density of the lattice structure is 110 W∙cm−2, and the critical heat flux density of the traditional flat plate is 45 W∙cm−2. In addition, the effects of cell structures indicated that for frame cells, the heat transfer effect of nonuniform frames was inferior to that of uniform frames; for face-centred cubic (FCC) cells, the nonuniform and uniform frames exhibited the same trend. However, the heat flow density of FCC cells was 25% higher than that of frame structures. [ABSTRACT FROM AUTHOR]

Titanium has attracted considerable attention for applications in several industries owing to its low density and high tensile strength; however, its poor surface hardness and wear rate limit these applications. This study aims to improve the mechanical properties of the titanium surface. A new surface modification process for titanium is proposed, wherein Ar is used to dilute O 2 and laser gas oxidizing is performed on the titanium surface in this dilute O 2 environment. The feasibility of this process was verified at different O 2 /Ar gas flow ratios. The evolution of the molten pool generated by laser irradiation was analyzed using a high-speed camera combined with a welding glass filter. The surface and cross-section of the modified layer were observed by scanning electron microscopy and X-ray diffraction to study its forming characteristics. The microhardness was characterized, and friction and wear tests were carried out to study the properties of the modified layer. The experiments proved that diluting O 2 with Ar can reduce the rate of the reaction between O 2 and titanium and enhance the process controllability; therefore, laser gas oxidizing of the titanium surface in a dilute O 2 environment is feasible. The O 2 to Ar gas flow ratio significantly affected the process controllability, as well as the surface roughness, number of cracks, microhardness, and wear resistance of the modified layer. With a moderate O 2 to Ar gas flow ratio, optimal formation and performance of the modified layer can be achieved. The oxygen content and hardness below the modified layer were lower than those of the modified layer; however, they higher than those of commercially-pure titanium. • Diluting O 2 with Ar reduces Ti oxidation rates and enhances process controllability. • Laser gas oxidizing of Ti surfaces in dilute O 2 is practically feasible. • Moderate O 2 to Ar gas flow ratios are best for modified layer performance. • Hardness and O content below modified layer are higher than in commercial titanium. [ABSTRACT FROM AUTHOR]

Post-processing is often inevitable for most additively manufactured components in order to improve material properties and product quality. In this study, the influence of post-heat treatments (PHTs) at 871 °C and 1177 °C on the microstructure and mechanical properties of a nickel-base Hastelloy C276 alloy prepared using wire arc additive manufacturing (WAAM) were investigated. The results showed that after a PHT at 871 °C, the as-built alloy was strengthened due to the formation of a large amount of Mo-rich nano-sized μ phase in the interdendritic areas. This was at the expense of a significant ductility loss. In contrast, no μ phase precipitates were observed after PHT at 1177 °C. Furthermore, the 1177 °C treatment led to the dissolution of the Mo-rich p phase which was present in the as-built sample, increased solid-solution strengthening, and improvements in both strength and ductility concurrently. This study enables an improved understanding of post-processing-microstructure-property inter-relationships for Hastelloy C276 alloy prepared by WAAM, providing guidelines for further microstructure optimization through PHT to improve the material's mechanical properties. • Hastelloy C276 using WAAM can be strengthened by post heat treatment (PHT). • PHT at 871 °C leads to the highest strength but lowest ductility due to intermetallics. • PHT at 1177 °C shows a combination of increased strength and lowered anisotropy. [ABSTRACT FROM AUTHOR]

Multiple factors affecting the sulfonated poly (arylene ether) proton exchange membrane materials are worthy of being systematically explored. In order to investigate the variation of membrane materials based on ion exchange capacity (IEC) and hydrophilic segment length, three series of dense sulfonated poly (arylene ether)s (mt-SPAE-y, dt-SPAE-y and tt-SPAE-y) containing mono-, di- and tri-sulfonated tetraphenylmethane structural units were synthesized. Each series contains three sulfonated copolymers with different IEC values. Small angle X-ray scattering and transmission electron microscopy results show that increasing the IEC value is conducive to the aggregation of hydrophilic ion clusters, while the growth of hydrophilic segment length helps to the formation of larger hydrophilic ion clusters. Both variations favor the construction of connected hydrophilic ion channels. Based on the highest IEC value and the longest hydrophilic segment length, the tt-SPAE-1.94 membrane forms a connected hydrophilic channel that allows it to exhibit the highest proton conductivity and lowest activation energy of the proton conductivity. Good thermal properties, mechanical properties and oxidation resistance lay the foundation for the durability of the membrane in fuel cells. Finally, the tt-SPAE-1.94 membrane was used for membrane electrode assembly at 80 °C and 95% relative humidity, exhibiting a power density of 418 mW cm−2 in H 2 /air fuel cell test. In summary, both the increase in the IEC value and the length of the hydrophilic segment contribute to the formation of good hydrophilic-hydrophobic phase morphology, thereby enhancing the macroscopic properties of the sulfonated poly (arylene ether) proton exchange membrane material. The results prove that these three series of membranes show outstanding prospects in actual fuel cell operation and have considerable research value. Three series of dense sulfonated poly (arylene ether)s (mt-SPAE-y, dt-SPAE-y, and tt-SPAE-y) containing mono-, di- and tri-sulfonated tetraphenylmethane structural units were synthesized. Each series contains three sulfonated copolymers with different IEC values. Image 1 • Three series of densely sulfonated poly (arylene ether)s were synthesized. • SAXS and TEM test proved considerable phase separation morphology. • The tt-SPAE-1.94 membrane exhibits excellent cell performance. • The stability test lays the foundation for the durability of the membranes. [ABSTRACT FROM AUTHOR]