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Electric Arc Furnaces (EAFs) play a pivotal part in the steel industry, offering a versatile of producing high-quality steel. This paper conducts an in-depth examination of the EAF, along with exploring mathematical modeling and optimization techniques pertinent to this furnace. Additionally, it delves into the global steel production capacity employing this technology, introduces different processes associated with EAF, scrutinizes the energy balance of EAFs, and provides an overview of numerical and simulation modeling in this context. The core focus of this extensive review is the diverse landscape of EAF simulation methods. It places particular emphasis on understanding the key components and stages of the EAF process, including charging, melting, refining, tapping, and slag removal. The review delves into the wide array of approaches and methodologies employed in EAF modeling, spanning from innovative computational fluid dynamics (CFD) and finite element analysis to the intricacies of mathematical and thermodynamic models. Furthermore, the paper underscores the importance of simulation in predicting and enhancing crucial aspects such as heat transfer, chemical reactions, and fluid dynamics within the EAF. By doing so, it contributes to the optimization of energy efficacy and the ultimate quality of steel produced in these furnaces. In conclusion, this review identifies gaps in existing knowledge and offers valuable recommendations for improving mathematical process models, underscoring the continuous efforts to enhance the efficiency, sustainability, and environmental impact of steel production processes. In conclusion, several techniques aimed at enhancing both production rates and the quality of the melting process in EAF have been put forward.

Energy harvesting using piezoelectric transduction offers a promising alternative to the conversion of kinetic energy like ambient vibration and rotational motion into useful electricity in self-powered electronic devices. To improve the reliability and effective bandwidth of rotational piezoelectric energy harvesters (RPEHs), a novel rotational energy harvester utilizing an asymmetrically deformed piezoelectric transducer excited by a magnetic attractive force is presented in this paper. Unlike the previous most RPEHs where piezoelectric elements experienced the symmetrical bidirectional strain, the presented piezoelectric transducer was only subjected to unidirectional compressive strain. It made the best use of the deformation characteristics of PZT vibrators where their allowable compressive stress was far greater than the allowable tensile stress, thus reducing the damage possibility of PZT vibrators under unexpected heavy loads. To prove the feasibility and explore the influence of the related structural parameters on the power generation performance, the theoretical analysis, simulation, fabrication and experiments were performed for the novel RPEH. The results showed that some parameters like the number ratio (α) and the rotary radius (R) of the exciting magnets brought a strong impact on the response characteristics of the presented RPEH. With the increasing rotary radius R, both the optimal rotating speed and effective bandwidth were decreased, whereas there were few studies on the effect of the rotary radius R of exiting force in previously reported RPEHs. In the case of rotary radius R = 60 mm, the maximum output voltage of 130 V with α = 0.5 was achieved. A maximum output power of 3.89 mW was obtained across 41 kΩ at the rotating speed of 856 r/min. It is expected this research can provide a beneficial reference for enhancing the reliability of existing RPEHs.

Magnesium alloys with integration of degradability and good mechanical performance are desired for vascular stent application. Drug-eluting coatings may optimize the corrosion profiles of magnesium substrate and reduce the incidence of restenosis simultaneously. In this paper, poly (trimethylene carbonate) (PTMC) with different molecular weight (50,000 g/mol named as PTMC5 and 350,000 g/mol named as PTMC35) was applied as drug-eluting coatings on magnesium alloys. A conventional antiproliferative drug, paclitaxel (PTX), was incorporated in the PTMC coating. The adhesive strength, corrosion behavior, drug release and biocompatibility were investigated. Compared with the PLGA control group, PTMC coating was uniform and gradually degraded from surface to inside, which could provide long-term protection for the magnesium substrate. PTMC35 coated samples exhibited much slower corrosion rate 0.05 μA/cm2 in comparison with 0.11 μA/cm2 and 0.13 μA/cm2 for PLGA and PTMC5 coated counterparts. In addition, PTMC35 coating showed more stable and sustained drug release ability and effectively inhibited the proliferation of human umbilical vein vascular smooth muscle cells. Hemocompatibility test indicated that few platelets were adhered on PTMC5 and PTMC35 coatings. PTMC35 coating, exhibiting surface erosion behavior, stable drug release and good biocompatibility, could be a good candidate as a drug-eluting coating for magnesium-based stent.

Abstract Background Simao pine is one of the primary economic tree species for resin and timber production in southwest China. The exploitation and utilization of Simao pine are constrained by the relatively lacking of genetic information. Construction a fine genetic linkage map and detecting quantitative trait locis (QTLs) for growth-related traits is a prerequisite section of Simao Pine's molecular breeding program. Results In our study, a high-resolution Simao pine genetic map employed specific locus amplified fragment sequencing (SLAF-seq) technology and based on an F1 pseudo-testcross population has been constructed. There were 11,544 SNPs assigned to 12 linkage groups (LGs), and the total length of the map was 2,062.85 cM with a mean distance of 0.37 cM between markers. According to the phenotypic variation analysis for three consecutive years, a total of seventeen QTLs for four traits were detected. Among 17 QTLs, there were six for plant height (Dh.16.1, Dh16.2, Dh17.1, Dh18.1–3), five for basal diameter (Dbd.17.1–5), four for needle length (Dnl17.1–3, Dnl18.1) and two for needle diameter (Dnd17.1 and Dnd18.1) respectively. These QTLs individually explained phenotypic variance from 11.0–16.3%, and the logarithm of odds (LOD) value ranged from 2.52 to 3.87. Conclusions In our study, a fine genetic map of Simao pine applied the technology of SLAF-seq has been constructed for the first time. Based on the map, a total of 17 QTLs for four growth-related traits were identified. It provides helpful information for genomic studies and marker-assisted selection (MAS) in Simao pine.

This paper presents and investigates a new three-rotation (3R) parallel compliant mechanism that uses compliant rods to achieve three rotations. The mechanism is designed for use in pointing devices or as a spatial parallel manipulator. The mobility analysis is based on the Cosserat rod model and Lagrangian dynamics equations. The dynamics equations are then effectively solved using the back-propagation neural network and chaos-enhanced accelerated particle swarm optimization. After studying the mobility of the moving platform, a simplified model is proposed and used for kinematic analysis. The analysis of motion includes discussions on forward kinematics, inverse kinematics, singularities, and the workspace. Furthermore, experiments with a prototype are conducted to verify the accuracy and stability of the mobility analysis and the simplified model.

The effect of extracellular matrix (ECM) stiffness on embryonic trophoblast cells invasion during mammalian embryo implantation remains largely unknown. In this study, we investigated the effects of ECM stiffness on various aspects of human trophoblast cell behaviors during cell–ECM interactions. The mechanical microenvironment of the uterus was simulated by fabricating polyacrylamide (PA) hydrogels with different levels of stiffness. The human choriocarcinoma (JAR) cell lineage was used as the trophoblast model. We found that the spreading area of JAR cells, the formation of focal adhesions, and the polymerization of the F-actin cytoskeleton were all facilitated with increased ECM stiffness. Significantly, JAR cells also exhibited durotactic behavior on ECM with a gradient stiffness. Meanwhile, stiffness of the ECM affects the invasion of multicellular JAR spheroids. These results demonstrated that human trophoblast cells are mechanically sensitive, while the mechanical properties of the uterine microenvironment could play an important role in the implantation process.

Magnesium alloys with integration of degradability and good mechanical performance are desired for orthopedic implants. In this paper, Mg–2Sr–Ca and Mg–2Sr–Zn alloys were prepared and the degradation as well as the bone response were investigated. Compared with the binary Mg–2Sr alloys, the addition of Ca and Zn improved the in vitro and in vivo corrosion resistance. Mg–2Sr–Ca and Mg–2Sr–Zn alloys exhibited more uniform corrosion and maintained the configuration of the implants 4 weeks post-implantation. The in vivo corrosion rates were 0.85 mm/yr for Mg–2Sr–Zn and 1.10 mm/yr for Mg–2Sr–Ca in comparison with 1.37 mm/yr for Mg–2Sr. The in vitro cell tests indicated that Mg–2Sr–Ca and Mg–2Sr–Zn alloys exhibited higher MG63 cell viability than Mg–2Sr alloy. Furthermore, these two alloys can promote the mineralization and new bone formation without inducing any significant adverse effects and this sound osteogenic properties suggest its attractive clinical potential.

This article proposes a new reconfigurable parallel mechanism using a spatial overconstrained platform. This proposed mechanism can be used as a machine tool. The mobility is analyzed by Screw Theory . The inverse kinematic model is established by applying the closed-loop equation. Next, the dynamic model of the presented mechanism is established by Lagrange formulation. To control the presented mechanism, some controllers have been used. Based on this dynamic model, the fuzzy-proportion integration differentiation (PID) controller is designed to track the trajectory of the end effector. For each limb, a sliding mode controller is applied to track the position and velocity of the slider. Finally, some simulations using ADAMS and MATLAB are proposed to verify the effectiveness and stability of these controllers.

Docynia indica (Wall.) Decne. (Duo-Yi) is a high economic value for exploitation and utilization wild fruit tree species with edible and medicinal values in southwest China. We have sequenced the chloroplast genome to facilitate genetic improvement of this species and to assess phylogenetic relationships among major lineages. The result showed that the total chloroplast genome size of Duo-Yi was 159,546 bp in length, containing a pair of inverted repeats (IRs) of 26,369 bp, which were separated by a large single copy (LSC) and small single copy (SSC) of 87,650 bp and 19,158 bp, respectively. The overall guanine-cytosine (GC) content of the chloroplast genome was 36.6%. There were 125 genes in the chloroplast genome, which including 82 protein-coding genes, 35 transfer RNA genes, and 8 ribosomal RNA genes. Among these genes, there were 14 genes with one intron and 3 genes have two introns. The result of phylogenetic analysis indicated that the Duo-Yi was closely related to the genera of Malus doumeri.

Vertical take-off and landing unmanned aerial vehicles (VTOL UAV) are widely used in various fields because of their stable flight, easy operation, and low requirements for take-off and landing environments. To further expand the UAV’s take-off and landing environment to include a non-structural complex environment, this study developed a landing gear robot for VTOL vehicles. This article mainly introduces the adaptive landing control of the landing gear robot in an unstructured environment. Based on the depth camera (TOF camera), IMU, and optical flow sensor, the control system achieves multi-sensor data fusion and uses a robotic kinematical model to achieve adaptive landing. Finally, this study verifies the feasibility and effectiveness of adaptive landing through experiments.

The main challenge in analyzing compliant sensor systems is how to calculate the large deformation of flexural complements. Our study proposes a new model that is called the spline pseudo-rigid-body model (spline PRBM). It combines dynamic spline and the pseudo-rigid-body model (PRBM) to simulate the flexural complements. The axial deformations of flexural complements are modeled by using dynamic spline. This makes it possible to consider the nonlinear compliance of the system using four control points. Three rigid rods connected by two revolute (R) pins with two torsion springs replace the three lines connecting the four control points. The kinematic behavior of the system is described using Lagrange equations. Both the optimization and the numerical fitting methods are used for resolving the characteristic parameters of the new model. An example is given of a compliant mechanism to modify the accuracy of the model. The spline PRBM is important in expanding the applications of the PRBM to the design and simulation of flexural force sensors.

Background and objective All the advanced NSCLC patients that received EGFR-TKI therapy will eventually relapse after a period of efficacy. The aim of this study is to investigate the serum biomarkers as potential predictive factors for the efficacy of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) targeted therapy in advanced non-small cell lung cancer. Methods Twenty self-paired serum samples were collected from 9 advanced NSCLC patients that evaluated as disease control (SD or PR) after gefinitib therapy, at the time points of before and after gefinitib treatment but 2 weeks before being evaluated as disease progress. All samples were pre-separated by WCX microbeads, and then detected on the MALDI-TOF-MS platform of Bruker AutoflexTM. ClinProTools (Version: 2.1) was used to analyze the differentially expressed proteins. Results There were 7 protein peaks (m/z), 3242.09, 8 690.36, 2 952.64, 3 224.04, 1 450.51, 1 887.8 and 3 935.73 found statistically differentially expressed between the self-paired samples. Three proteins (3 242.09, 2 952.64 and 3 224.04) were down-regulated and four proteins (8 690.36, 1 450.51, 1 887.8 and 3 935.73) up-regulated in gefinitib treated sera. Conclusion The data here suggest that several specific protein peaks might indicate gefinitib resistance, yet the identities of these proteins and the mechanisms underlying the responsiveness to gefinitib treatment need further investigation.

The Sustainable Development Goals (SDGs) have made it necessary for us to reevaluate the connection between environmental preservation and economic growth. The article uses Chinese city-level panel data from 2011 to 2019 to analyze the relationship between digital finance (DF) and environmental performance (EP), relaxing the linear relationship in the conventional empirical model and applying the partial linear functional-coefficient (PLFC) model, in order to better understand the factors influencing EP. The findings indicate as follows: (i) DF can greatly improve EP, and the robustness analysis confirms this statement. (ii) Science, technology, and innovation (STI) influence the promotion effect of DF on EP; when the level of STI exceeds a certain threshold, the promotion effect of DF on EP increases, and this effect increases with the level of STI. (iii). There is substantial geographical variation in the moderating influence of STI level. It has a larger role in eastern coastal cities. Finally, policy suggestions are offered to promote DF and increase EP based on the nonparametric link between those two variables. [ABSTRACT FROM AUTHOR]

Insufficient trophoblast migration and impaired uterine spiral artery remodeling are implicated in the pathogenesis of preeclampsia, contributing to inadequate placentation. However, the molecular mechanism underlying this process remains unclear. Aerobic glycolysis, which produces substantial lactate, is crucial for establishing a favorable microenvironment for early uterine preparation and supporting embryo implantation and trophoblast migration. In the present study, we have demonstrated that SORBS2, an RNA-binding protein, regulated aerobic glycolysis and significantly improved trophoblast migration in vitro. Our results showed that SORBS2 expression was significantly reduced in human PE placentas and trophoblasts during hypoxia. Overexpression of SORBS2 enhanced cell proliferation and migration, whereas knockdown of SORBS2 decreased these functions in HTR-8/SVneo cells. Mechanistic studies have demonstrated that SORBS2 directly interacts with the 3' untranslated regions (UTRs) of key glycolysis-related genes, specifically HK2. This interaction results in enhanced stability of HK2 and activation of glycolysis. Moreover, silencing HK2 abrogated the enhancement of proliferation and migration of HTR-8/SVneo cells induced by SORBS2. In conclusion, our findings suggest that the downregulation of SORBS2 may contribute to the pathogenesis of preeclampsia by regulating mRNA stability and inhibiting trophoblast migration during placentation. [ABSTRACT FROM AUTHOR]