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Recapitulating the natural extracellular physical microenvironment has emerged as a promising method for tissue regeneration, as multiple physical interventions, including ultrasound, thermal and electrical therapy, have shown great potential. However, simultaneous coupling of multiple physical cues to highly bio-mimick natural characteristics for improved tissue regeneration still remains formidable. Coupling of intrinsic electrical and mechanical cues has been regarded as an effective way to modulate tissue repair. Nevertheless, precise and convenient manipulation on coupling of mechano-electrical signals within extracellular environment to facilitate tissue regeneration remains challengeable. Herein, a photothermal-sensitive piezoelectric membrane was designed for simultaneous integration of electrical and mechanical signals in response to NIR irradiation. The high-performance mechano-electrical coupling under NIR exposure synergistically triggered the promotion of osteogenic differentiation of stem cells and enhances bone defect regeneration by increasing cellular mechanical sensing, attachment, spreading and cytoskeleton remodeling. This study highlights the coupling of mechanical signals and electrical cues for modulation of osteogenesis, and sheds light on alternative bone tissue engineering therapies with multiple integrated physical cues for tissue repair. [ABSTRACT FROM AUTHOR]

Background: Pediatric-type diffuse high-grade glioma (pHGG) is the most frequent malignant brain tumor in children and can be subclassified into multiple entities. Fusion genes activating the MET receptor tyrosine kinase often occur in infant-type hemispheric glioma (IHG) but also in other pHGG and are associated with devastating morbidity and mortality. Methods: To identify new treatment options, we established and characterized two novel orthotopic mouse models harboring distinct MET fusions. These included an immunocompetent, murine allograft model and patient-derived orthotopic xenografts (PDOX) from a MET-fusion IHG patient who failed conventional therapy and targeted therapy with cabozantinib. With these models, we analyzed the efficacy and pharmacokinetic properties of three MET inhibitors, capmatinib, crizotinib and cabozantinib, alone or combined with radiotherapy. Results: Capmatinib showed superior brain pharmacokinetic properties and greater in vitro and in vivo efficacy than cabozantinib or crizotinib in both models. The PDOX models recapitulated the poor efficacy of cabozantinib experienced by the patient. In contrast, capmatinib extended survival and induced long-term progression-free survival when combined with radiotherapy in two complementary mouse models. Capmatinib treatment increased radiation-induced DNA double-strand breaks and delayed their repair. Conclusions: We comprehensively investigated the combination of MET inhibition and radiotherapy as a novel treatment option for MET-driven pHGG. Our seminal preclinical data package includes pharmacokinetic characterization, recapitulation of clinical outcomes, coinciding results from multiple complementing in vivo studies, and insights into molecular mechanism underlying increased efficacy. Taken together, we demonstrate the groundbreaking efficacy of capmatinib and radiation as a highly promising concept for future clinical trials. [ABSTRACT FROM AUTHOR]

The present work investigates the energy absorption performance of carbon fibre-reinforced polymer (CFRP) laminates subjected to low-velocity normal and oblique impacts. Experimental tests are conducted on laminates exposed to varying impact energies at both normal and oblique angles. The numerical model is developed to simulate the dynamic response of the CFRP. The research employs a combination of experimental and numerical methods to reveal the underlying damage mechanisms. The changes observed in the oblique impact response are explained through an analysis of the damage mechanisms. Analytical models for each energy absorption mechanism are proposed based on the principles of energy conservation and the theory of large bending deformation of anisotropic materials. The energy absorption performance of the laminates under oblique impacts, considering rebound and penetration conditions, is discussed. It is found that the delamination is the primary energy absorption mechanism of CFRP laminate under rebound conditions, while elastic deformation of fibres is the primary energy absorption mechanism under penetration conditions. Furthermore, the energy absorption performance of the laminate is found to be affected by the peak force and effective thickness of the plate, which change with the oblique angle. This paper makes a significant contribution by utilising experimental, numerical, and theoretical approaches to gain insights into the damage mechanisms of laminates subjected to oblique impacts. [ABSTRACT FROM AUTHOR]

A Fe-Co dual-metal co-doped N containing the carbon composite (FeCo-HNC) was prepared by adjusting the ratio of iron to cobalt as well as the pyrolysis temperature with the assistance of functionalized silica template. Fe1Co-HNC, which was formed with 1D carbon nanotubes and 2D carbon nanosheets including a rich mesoporous structure, exhibited outstanding oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) catalytic activities. The ORR half-wave potential is 0.86 V (vs. reversible hydrogen electrode, RHE), and the OER overpotential is 0.76 V at 10 mA cm−2 with the Fe1Co-HNC catalyst. It also displayed superior performance in zinc–air batteries. This method provides a promising strategy for the fabrication of efficient transition metal-based carbon catalysts. [ABSTRACT FROM AUTHOR]

The cross-section, thickness, and material of the autobody structure determine the crashworthiness and lightweight level. Different from the variables in traditional autobody design that are considered separately, the basic theory of 3G-optimization is to simultaneously consider geometric shape (Geometry), the thickness of structure (Gauge), and material grade (Grade) in structural optimization design, which is conducive to maximizing the lightweight potential of the structure. This paper presents a cross-section optimization method for multi-cell thin-walled structures based on 3G-optimization, which is used in the structural design of crash box. Based on full width frontal collision condition, the cross-section shape, thickness, and material variables of the multi-cell crash box are optimized simultaneously. Multiple sets of optimization schemes show obvious weight reduction effect while ensuring safety. Besides, the sub-system decoupling method and hybrid cellular automaton (HCA) method are applied to 3G-optimization process, which is beneficial to improve the calculation efficiency and provide a theoretical basis for the definition of the initial design space for 3G-optimization. [ABSTRACT FROM AUTHOR]

Homogenization methods can characterize the mechanical properties of these materials based on appropriate constitutive models and data. They are also applied to the characterization of mechanical parameters under complex geotechnical conditions in geotechnical engineering because of the complexity and heterogeneous nature of geotechnical materials. Unfortunately, existing homogenization methods for geotechnical mechanical parameters often incur immense computational costs. Hence, a framework that utilizes finite element analysis for generating a dataset which is then trained using a Bayesian Optimized Back Propagation Artificial Neural Network (BP-ANN) to obtain the homogenized Mohr–Coulomb parameters of the soils is proposed. This is the first time that Bayesian optimization and a BP-ANN have been used in conjunction to predict the homogenized mechanical parameters of soils. The dataset used for training the data is generated using the commercial FEM software ABAQUS (6.10). The maximum difference between the top and bottom part of the tunnel of the heterogeneous model and homogeneous model of our test cases only varies by 5.3%, thereby verifying the excellence of the Bayesian Optimized BP-ANN. [ABSTRACT FROM AUTHOR]

Support Vector Machine (SVM) is a well-known classification technique which has achieved excellent performance in many nonlinear and high dimensional pattern recognition fields. However, due to the high time complexity of training SVM model, it's difficult to implement it for large-scale data sets. One of the most promising solutions is to reduce the training data used for establishing the optimal classification hyperplane by means of selecting relevant support vectors which are the only factors affecting the classification rule. Thus, instance selection method is an efficient pre-processing technique to reduce the computational complexity and storage requirements of the learning process. In this manuscript, considering the geometry-distribution of data sets, we propose a Half Shell Extraction (HSE) algorithm which falls into the condensation category of instance selection methods. Moreover, fuzzy distance metric based on locality sensitive hash is employed to accelerate the instance selection process. Empirically, an experimental study involving various of data sets is carried out to compare the proposed algorithm with five competitive algorithms, and the results obtained show that the proposed algorithm consistently outperforms the other algorithms in terms of accuracy, reduction capability and runtime. [ABSTRACT FROM AUTHOR]

The variable thickness hybrid square (VTHS) tubes are used to improve the energy absorption under oblique loading and the relative advantages compared with the uniform thickness hybrid square (UTHS) tubes are studied. First, a oblique compression test and finite element model were established to analyze the deformation mode and load-displacement curve of VTHS tube. Then, the parameter studies of VTHS and UTHS tubes were carried out. The results show that increasing thickness leads the structures to be prone to global bending mode, and the energy absorption performance is reduced. Compared with UTHS, VTHS tubes can increase the specific energy absorption when the progressive crushing mode occurred at the same loading angle. Meanwhile, the progressive crushing deformation with excellent energy absorption performance can still appear when the loading angle exceeds 30°. Finally, a unified equation for the relationship between the dimensionless mean crushing force and the loading angle was proposed. [ABSTRACT FROM AUTHOR]

The fabrication of various 3D tissue engineering tubular scaffolds with fibrous structures, to assist the human body in rapidly repairing a variety of ailments, is receiving more and more attention. Due to the inefficiency of the majority of fibrous preparation techniques, the question of how to rapidly produce the requisite three-dimensional tubular microfiber scaffold structures has become an urgent problem. In this study, an efficient polymer fiber preparation method was developed, using a high-speed airflow drive. Melt blending of polycaprolactone (PCL), polylactic acid (PLA), and tributyl citrate (TBC), was used for the printing material, to achieve the efficient preparation of tubular microfiber scaffolds with different structures. The scaffold diameter was as small as 2 mm, the wall thickness was up to 100 μm, and the fiber injection efficiency reached 15.48 g/h. By utilizing simulations to optimize the printing parameters and by adjusting the printing settings, it was possible to achieve a controlled fiber diameter in the range of 3 μm to 15 μm. In addition, plasma treatment was applied to the microfibers' surface, to increase their wettability, and the efficiency of the hydrophilic modification was demonstrated. Furthermore, the mechanical property test demonstrated that the fibers have a tensile strength of 1.36 ± 0.16 MPa and a tensile strain of 30.8 ± 3.5%. The radial compressive strain of the tubular scaffold could reach 60% of the original scaffold's diameter. Finally, the in vitro degradation of the fibers at various pH values was tested. The results showed that, under alkaline conditions, the surface of the fibers would be severely crushed and the rate of deterioration would increase. [ABSTRACT FROM AUTHOR]

A low-cost dual-chamber microbial fuel cell (MFC) was constructed as a biosensor for the rapid determination of biochemical oxygen demand (BOD) in domestic sewage. The operating conditions were optimized during the operation of the MFCs. The changes in the microbial community structure in the anode compartment were analyzed by 16S rRNA gene sequencing technology. The results indicated that the MFCs-BOD biosensor reached a steady state (maximum voltage of around 550 mV) within 1 week. The optimal working conditions were K3[Fe(CN)6] of 50 mm, anolyte pH of 7, and external resistance of 1000 Ω. The maximum current density and highest power density can be as high as 221.88 mA/m2 and 78.77 mW/m2, respectively. Compared with other studies, the start-up period of this MFCs-BOD biosensor was shorter (96–192 h), the determination range was wider (50–500 mg/L), and the determination time was short (within 3 h). The MFCs-BOD biosensor can accurately determine the BOD content of sewage water samples. The results of 16S rRNA gene sequencing showed that the anodic microbial community after the domestication changed significantly compared with the original inoculated anaerobic activated sludge flora, and the dominant electrogenic bacteria with the highest relative abundance belonged to Proteobacteria and Enterobacteria. The device has reliability and applicability in the BOD determination in actual domestic sewage, and this study provides a solid foundation for the future application of MFCs-BOD biosensor in the rapid determination of BOD in sewage. [ABSTRACT FROM AUTHOR]

Vehicle front-end structure has the characteristic of symmetry. The damage of occupants in the crash process is determined by the combined effect of the front-end structure and the restraint system of the vehicle. In this paper, the coupling relationship and an optimized method for the vehicle front-end structure and restraint system are studied based on vehicle crash dynamics, to reduce occupant injury. A fast solution algorithm for occupant motion response was established using a crash analytical model. Then, an occupant response database was established using the algorithm, to analyze the coupling relationship between the crash pulse and the restraint specific stiffness, with respect to the curve shape and parameters. The results showed that the combination of the concave crash pulse and upward restraint stiffness curve was the best coupling. Subsequently, a coupled optimization method of a concave pulse and upward restraint stiffness was proposed and combined with a crash analytical model and genetic algorithm (GA). The crash pulse and restraint stiffness of vehicle crash data from the NHTSA databases were optimized, as an example, to verify the effectiveness of the method. The optimal occupant acceleration was reduced by 44%. In addition, the feasibility of the optimal result is discussed, to provide a reference for occupant injury protection in traffic accidents. [ABSTRACT FROM AUTHOR]

When it comes to frontal vehicular crash development, matching the stiffness of the front-end structures reasonably, i.e., impact energy management, can effectively improve the safety of the vehicle. A multi-condition analytical model for a frontal vehicular crash is constructed by a three-dimensional decomposition theory. In the analytical model, the spring is used to express the equivalent stiffness of the local energy absorption space at the front-end structure. Then based on the analytical model, the dynamic responses and evaluation indexes of the vehicle in MPDB and SOB conditions are derived with the input of the crash pulse decomposition scheme. Comparing the actual vehicle crash data and the calculation results of the proposed solution method, the error is less than 15%, which verifies validity of the modeling and the accuracy of the solution. Finally, based on the solution method in the MPDB and the SOB conditions, the sensitivities of the crash pulse decomposition scheme to evaluation indexes are analyzed to obtain qualitative rules which guide crash energy management. This research reveals the energy absorption principle of the front-end structure during the frontal impact process, and provides an effective optimization method to manage the multiple conditions of the vehicle crash energy such as the FRB (frontal rigid barrier), the MPDB (mobile progressive deformable barrier), and the SOB (small overlap barrier). [ABSTRACT FROM AUTHOR]

Soil extra-cellular enzymes are the main driving force for microbial and biochemical processes, which makes them sensitive indicators for soil health and quality. Returning large amounts of sludge or its biochar to farmland may introduce exogenous substances into soil and have a significant impact on soil enzymatic activity. This study aimed to evaluate the effects of substances dissolved from sludge biomass and its biochar added at different amounts and produced at various temperatures (200 °C, 300 °C, and 450 °C) on the activity of acid phosphomonoesterase. Results showed that the activity of acid phosphomonoesterase was significantly inhibited by these dissolved substances from biochar pyrolyzed at different temperatures, especially at high concentrations of 50 mgC L−1 and upon the exposure to DBC200. The conformation of acid phosphomonoesterase became loose and flexible after exposure to dissolved organic matter (DOM) extracted from biochar in terms of reduced α-Helix contents and increased β-Turn contents as deduced from circular dichroism spectra. According to the results of multiple linear regression, it can be concluded that the increased contents of arsenic as well as protein-like components within dissolved substances may be responsible for the inhibited enzymatic activities and the altered enzymatic conformation. Our findings provide evidence that the pyrolysis of sludge at a higher temperature would be helpful to reduce its negative impacts on the soil ecosystem. [ABSTRACT FROM AUTHOR]

Titanium alloys with special macro-micro composite structures of directional hydrophobicity are difficult to prepare due to poor thermal conductivity and good corrosion resistance, inhibiting the wide engineering applications for aerospace, marine engineering, and biomedicine. To prepare macro-micro composite structures on the surface of titanium alloys and achieve directional hydrophobicity, the sub-millimeter structures with an edge width of 150 μm, a groove width of 250 μm, and a depth of 250 μm were fabricated on the titanium alloy by wire electrical discharge machining (WEDM) technology, and high voltage-induced weak electric arc machining (HV-μEAM) was used to fabricate micro-scale feature size micro-structures on the processed macro-structure edges. The influence of process parameters on the morphology of microstructures was studied experimentally. The smooth surface of the titanium alloy is isotropically hydrophilic, and its contact angle is 68°. After processing the macrostructure on the titanium alloy surface, it shows directional hydrophobicity after being modified by low surface energy materials. The macro-micro composite structure formed by HV-μEAM realizes a directional hydrophobic surface with contact angles (CA) of 140° (parallel direction) and 130° (perpendicular direction), respectively. This surface has been modified with low surface energy to achieve contact angles of 154° and 143°. The results of the abrasion resistance test show that under the load of 100 g, it retains directional hydrophobicity at a friction distance of 700 mm with 600# sandpaper. The existence of the sub-millimeter macrostructure is the reason for the directionality of surface hydrophobicity. The microstructure can realize the transformation of the titanium alloy surface from hydrophilic to hydrophobic. Under the combined effects of the macro and micro composite structure, the surface of the titanium alloy shows obvious directional hydrophobicity. [ABSTRACT FROM AUTHOR]

Shear strength evaluation in composites is still a problem that has not been fully solved. Dynamic shear strength evaluation is even more complicated. In present work, failure theories are used to determine the range of fiber orientations in which the evaluation of shear strength is feasible. The symmetrical laminate is used to eliminate coupled shear strain to improve measurement accuracy. Three different fiber orientation laminates are chosen for quasi-static tension test. And a combination of experimental and numerical method is carried out for high strain rate tests. The results show that the fiber orientation of ± 15° is suitable for evaluating the dynamic shear strength of CFRP (Carbon Fiber Reinforced Polymer). This study is of great significance to dynamic shear strength evaluation method of continuous fiber reinforced composites considering strain rate effect. [ABSTRACT FROM AUTHOR]

Square-circle hybrid section (SCHS) tubes under axial loading which combine the advantage of square tubes and circular tubes are investigated. Firstly, effective finite element models of SCHS tubes are established to study the crashworthiness characteristics. Through a series of finite element models, the influence of the geometry on the behaviour of crashworthiness is studied, including relative size of square and circular sections in SCHS tubes and the position of connecting plates. The results show that compared with corresponding traditional multi-cell tubes, SCHS tubes improve the performance in energy absorption, with a maximum increase of 40.49%, while reducing peak force and improving crushing load efficiency. Moreover, the deformation of elements constituting the SCHS tube is analysed, and deformation of arc-plate elements could be classified into three typical modes. According to the observed deformation modes, the theoretical model is proposed to predict the mean crushing force of SCHS tubes. The theoretical results show that it is in good agreement with the numerical results. [ABSTRACT FROM AUTHOR]

This article deals with initial material selection and design method of long fibre-reinforced thermoplastic (LFT) based on impact resistance requirements. In this study, effects of material properties and impact condition, including total fibre thickness, fibre aspect ratio and impactor diameter, on the minimum penetration energy of LFT plates are analysed based on experiments and validated numerical models. Mathematical expression is established between them. Applicability of the original model for LFT plate with different fibre aspect ratios subjected to different impactors is discussed. The minimum penetration energy is used as the bridge between energy absorption characteristics and material parameters, impact condition. Finally, an updated theoretical model for energy absorption analysis is proposed. We conclude that the updated semi-empirical model is a valuable tool for a first stage material selection and design. [ABSTRACT FROM AUTHOR]

This article presents a multi-component topology optimization method for thin-walled structures, which can be applied to two-dimensional plate components and three-dimensional tube components. Based on the theory of multi-component topology optimization for stamped sheet metal assemblies, an accurate calculation method for the Young's modulus of joint elements is provided. To avoid the discontinuous derivative and improve the optimization efficiency, a non-zero gradient-based material interpolation scheme with penalization is constructed. The cost of die-set materials can be controlled effectively by the maximum size of components. Several topology designs based on minimized compliance confirm the effectiveness of the proposed method. The topology solutions illustrate that the proposed method can realize the structural design of thin-walled structures which can meet the die-set material cost requirement. [ABSTRACT FROM AUTHOR]

Metal–organic framework (MOF) films are essential for numerous sensor and device applications. However, metal-organic framework materials have poor machinability due to their predominant powder-like nature, and their presence as the active layer in a device can seriously affect the performance and utility of the device. Herein, active layers of field-effect transistor (FETs) devices and chemiresistor gas sensors with high performance were constructed by loading Cu3(HITP)2 (HITP = 2,3,6,7,10,11-hexaiminotriphenylene) in situ-axial anchoring on oriented nanofiber arrays prepared via electrospinning. The strong interaction between polar groups on the polymer chains and metal ions promotes the nucleation of Cu3(HITP)2, steric hindrance makes particles of Cu3(HITP)2 with uniform size, morphology, and good crystallinity during nucleation by liquid phase epitaxial growth (LPE). Influences of differently-oriented Cu3(HITP)2 NFAs-based FETs on the electrical properties were studied, optimally oriented Cu3(HITP)2 NFAs-based FETs showed good mobility of 5.09 cm2/V·s and on/off ratio of 9.6 × 103. Moreover, excellent gas sensing response characteristics were exhibited in sensing volatile organic compounds (VOCs). Chemiresistor gas sensors with high response value, faster response and recovery are widely suited for VOCs. It brings new inspirations for the design and utilization of electrically conductive MOFs as an active layer for FETs and sensor units for chemiresistor gas sensors. [ABSTRACT FROM AUTHOR]

This paper presents a design method for manufacturable casting parts based on topology optimization of structural assemblies, which considers the geometry requirement and the manufacturing constraint of die-set material cost. The problem formulation follows the previous work presented in multi-component topology optimization for stamped sheet metal assemblies (MTO-S). Based on the vector method combined with Heaviside function, the moldability constraints for casting parts is formulated. As the base structure of component is easily misidentified as an undercut structure by the moldability constraints in the structural assemblies, the component baseline is proposed to realize the automatic filtering of the "fake" undercut structures which can be extended to the parting line to obtain the form of two-mold design. Several numerical examples on compliance minimization of single-mold and two-mold casting parts are conducted to verify the validity of the proposed method. The optimized results show that there is no interior void for each component and the component manufacturability has been improved obviously. The setting of minimum-area bounding box (MABB) area constraint limits and the number of components will have a significant effect on the performance of the optimized structure. Users can achieve the desirable solution based on their actual demand by making trade-offs between the structural performance and manufacturing cost. [ABSTRACT FROM AUTHOR]

Based on the theoretical crashworthiness model of variable thickness rectangular section tubes, this article simplified the super-folding element to analyze the energy absorption characteristics of variable thickness 12 right-angles section (VTTRS) tubes during axial crushing. To discuss the deformation mode of VTTRS tubes, a series of finite element models were built based on the verified finite element model of variable thickness rectangle section tubes. Then, the deformation of VTTRS tubes was studied to obtain the structures deforming in stable mode which have a great performance in energy absorption. Meanwhile, a theoretical solution of the mean crushing force for VTTRS tubes was proposed and verified by establishing three groups of finite element models with different thicknesses and thickness gradients. Finally, a prediction for crash box was presented and the results showed the great potential of VTTRS tubes in energy absorption and explained the important role played by the theoretical model for vehicle during concept design stage. [ABSTRACT FROM AUTHOR]

Electric vehicles have become the main trend of the future development of the automotive industry due to their advantages such as energy conservation and environmental protection, strong acceleration capability, and low noise. This paper uses a volume-produced fuel passenger vehicle P5 as a prototype. Based on the given driving mode and traction battery pack layout of a battery electric vehicle (BEV) EP5, considering the static stiffness and crashworthiness simultaneously, the equivalent static load (ESL) method is used to perform multi-load topology optimization on the body-in-white (BIW) of the BEV. Then the load paths of EP5 are proposed. The front-end structures of the vehicle body are redesigned by using topology optimization and size optimization, which improve crashworthiness and fully tap the lightweight potential of EP5. [ABSTRACT FROM AUTHOR]

The newly revised GB 13057-2014 'The strength of the seats and their anchorages of passenger vehicles' replaces the static test with a dynamic test, which puts forward higher requirements on seat safety. Considering safety and lightweight design, the LFT (Long glass Fiber reinforced Thermoplastic) is used to replace the original steel seat back frame. Combined with energy absorption model and topology optimisation, the force transmission path and detail structure design under both the forward loading and rearward loading conditions are carried out. In order to analyse the occupant protection performance, numerical models of composite seat and HybridIII dummy are established, and the safety and lightweight effect of LFT seat back frame are optimised and verified. [ABSTRACT FROM AUTHOR]

Nowadays, in some countries and regions the inhalable suspended particles in the air have caused irreversible harm to human health. The filtration performance of the material is the key to the application, meanwhile, the bacteria and viruses accumulated on the surface of the filter material have caused potential threats. And a large amount of discarded non-degradable filter materials caused secondary pollution of the environment. Therefore, filter material with high interception efficiency, antimicrobial and environmental friendliness properties is urgent needed. In this study, electrospinning was used to prepare an antibacterial fibrous membrane composed of an organic–inorganic composite whose continuous phase was polylactic acid (PLA), with quartz monzonite porphyry (QMP) particles decorated with silver nanoparticles (Ag NPs) as the inorganic filler phase. Its filtration and antibacterial properties were investigated, and the results showed that the main factors affecting the filtration efficiency were the ratio of the filler particles to the continuous phase and the particle size of the filler. The addition of QMP endowed the membrane with antibacterial properties, which were further improved after decorating Ag NPs with QMP. The barrier rate of the membrane for PM 2.5 reached 95.6%, and the inactivation ratios of the fibrous membrane for Escherichia coli were 48% and 98% before and after decoration by Ag NPs, respectively. [ABSTRACT FROM AUTHOR]

The safe and effective treatment for dyeing wastewater including harmful metal ions, which are important environmental pollution sources, has not been solved in the realistic industry. Using natural materials with short regeneration cycle should be valued in recognized and effective adsorption techniques. In this study, hydroxyl-rich tannin molecules were successfully modified on palm leaf sheath fibers (PLSF) to obtain multifunctional adsorbent for simultaneous removal of dye molecules and heavy metal ions in dyeing wastewater. As a result, modified PLSF can effectively adsorb reactive yellow 3 (RY3) dye molecules with a maximum adsorption capacity of 83.19 mg/g from dyeing wastewater, while the sample loaded with RY3 can adsorb Cr(VI) with a maximum adsorption capacity of 189.48 mg/g. XRD, SEM, FT-IR, and stereomicroscope are used to characterize the adsorbent samples. The kinetic and thermodynamic analysis results show that the adsorption of RY3 and Cr(VI) by the adsorbent is consistent with pseudo-second-order kinetics and the Langmuir isotherm model. The thermodynamic parameters of Cr(VI) adsorption indicate that adsorption is a spontaneous endothermic process and has good reusability of Cr(VI). [ABSTRACT FROM AUTHOR]

The newly revised GB 13057-2014 put forward high requirements for the dynamic occupant protection of passenger car seats. Due to the high density of steel, there is currently not much space for lightweight through structure improvement. In this paper, the quasi-static and dynamic mechanical properties of CFRP and corresponding simulations are used to study the mechanical behaviour of CFRP and verify the accuracy of simulation. It is now applied to the composite seat backplane structure design, and combined with the CFRP moulding process and the energy absorption characteristics of the car seat backplane to initially design the CFRP seat backplane material and structure. At the same time, considering the designability of the material itself, the ply optimisation technology under multi-condition is used to design the material and structure of the CFRP passenger car seat backplane. The new CFRP passenger car seat achieves significant weight reduction while meeting regulatory requirements. [ABSTRACT FROM AUTHOR]

This paper studies the modeling method and collaborative optimization of the dynamic responses for barrier-vehicle-occupant (BVO) system in engineering. The mechanical analytical model of BVO system is established to obtain not only the system dynamic responses but also the evaluation indexes of crashworthiness and compatibility. A collaborative optimization method that combines the BVO model and genetic algorithm is presented to obtain the optimal crash pulse of vehicle. An empirical case of an existing vehicle that has been in running in China is applied to verify this constructed model and solution method. Compared with the results of original alternative, the peak occupant acceleration and occupant load criterion (OLC) of barrier are reduced by 54.65% and 14.07%, respectively, and avoid the barrier bottoming out effectively. In addition, a sensitivity analysis is conducted and the results could be found that the heights about the middle part have a significant impact on occupant injury, OLC, and the middle backward part have a significant impact on the bottoming out of barrier, respectively. In summary, the concave shape crash pulse can improve crashworthiness and compatibility. This research reveals the principles of the BVO system and provides an effective tool to solve the optimization problem in conceptual design of vehicle. [ABSTRACT FROM AUTHOR]

Pediatric high-grade glioma (pHGG) is a major contributor to cancer-related death in children. In vitro and in vivo disease models reflecting the intimate connection between developmental context and pathogenesis of pHGG are essential to advance understanding and identify therapeutic vulnerabilities. Here we report establishment of 21 patient-derived pHGG orthotopic xenograft (PDOX) models and eight matched cell lines from diverse groups of pHGG. These models recapitulate histopathology, DNA methylation signatures, mutations and gene expression patterns of the patient tumors from which they were derived, and include rare subgroups not well-represented by existing models. We deploy 16 new and existing cell lines for high-throughput screening (HTS). In vitro HTS results predict variable in vivo response to PI3K/mTOR and MEK pathway inhibitors. These unique new models and an online interactive data portal for exploration of associated detailed molecular characterization and HTS chemical sensitivity data provide a rich resource for pediatric brain tumor research. Patient-derived xenografts provide a resource for basic and translational cancer research. Here, the authors generate multiple pediatric high-grade glioma xenografts, use omics technologies to show that they are representative of primary tumours and use them to assess therapeutic response. [ABSTRACT FROM AUTHOR]

The newly revised national standard GB 13057-2014 'The strength of the seats and their anchorages of passenger vehicles' puts forward higher requirements for occupant protection of passenger car seats in the dynamic test. Simply improving safety performance may increase seat weight. Considering the dual requirements of safety performance and light weight, this article adopted the topology optimisation method and took into account the strength requirements of multiple loading conditions: forward loading and rearward loading, and finally optimised the structure of seat backrest frame. By changing the weight ratio of loading conditions and the topological mass fraction, the optimal material distribution and force transmission paths of seat backrest frame were optimised. At the same time, considering the ergonomics and the strength of the seat fixing points, the structure of seat backrest frame was fully optimised. On the premise of improving the safety performance of the seats (occupant protection), significant weight reduction was also achieved. [ABSTRACT FROM AUTHOR]

The chiral separation of five antihistamine drugs including meclizine, cloperastine, azelastine, carbinoxamine and mequitazine was studied by HPLC combined with chiral stationary phases. The effect of chiral columns, the types and contents of organic modifiers, and the concentrations of basic additive on the chiral separation was evaluated and optimized in detail. The best enantioselectivity for these compounds was observed using Chiralpak IA and Chiralpak ID as chiral columns. In particular, baseline separation of carbinoxamine with the largest resolution of 3.82 was achieved using a Chiralpak ID column with the mobile phase of acetonitrile–water–ammonia solution (90 : 10 : 0.1, v/v/v). Based on this result, an enantioselective HPLC-MS/MS method was developed and validated for determination of carbinoxamine enantiomers in rat plasma. Also, this method was successfully applied in evaluating the pharmacokinetic profiles of carbinoxamine enantiomers. Good linearity (r > 0.99) for both enantiomers over a concentration range of 0.1–100 ng mL−1 was obtained. The accuracy ranged from 87.4% to 113.8%, and the intra-day and inter-day precisions were below 9.4% for (+)- and (−)-carbinoxamine at three quality control levels. The pharmacokinetic parameters demonstrated that the absorption and elimination processes of carbinoxamine enantiomers were not stereoselective, and chiral inversion did not occur either in rats. [ABSTRACT FROM AUTHOR]

The front-end structure crashworthiness design during the conceptual design phase of automobile can shorten production cycle and has a great significance to improve safety. This paper proposes a three-stage target decomposition method to design crash pulse and manage the crash energy absorption of front-end structure of automobile. In this method, the theoretical optimal solution of the Equivalent Dual-trapezia Wave (EDTW) is calculated by the overall layout parameters of automobile and safety requirements of occupant. The optimal EDTW, as the target crash pulse, is decomposed to segments based on the reserved longitudinal crush space and the lateral energy absorption ratio of the front-end substructure. In addition, simple mathematical and mechanical principles are applied to calculate the performance objectives of key energy absorption substructures. Finally, an empirical application of M6 model is conduct to verify the validity of EDTW optimal solution and the realizability of target decomposition. The result shows that this proposed method is effective for the conceptual design of new cars and model change of existing cars. The design process does not rely on large computing software and empirical data and the design result has a guiding role in CAE analysis of automobile safety. [ABSTRACT FROM AUTHOR]

This paper presents a two degrees of freedom model–based optimization method for occupant restraint systems (ORS), applied before the finite element analysis in a vehicle crash. The method considers the effects of restraint systems (seatbelt, airbag, seat, and knee baffle) on the occupant and establishes the analytical models of them. The method reveals the effect essence of the ORS and takes the occupant response as the target to optimize the restraint system parameters rapidly. The multi-rigid body model of a Toyota Camry vehicle is established to verify the validity and reliability of two degrees of freedom model (TDFM). Comparing the results of the two models, the trends of acceleration-time curves are consistent, and the 85% errors of occupant responses are within 20%. Then, the practicality and effectiveness of the optimization method are confirmed by the instance of Camry ORS. The errors of results solved by optimization and the MADYMO model are all less than 20%. The optimization method can be used to provide an initial parameter range for the finite element simulation to improve the efficiency of the traditional optimization process. [ABSTRACT FROM AUTHOR]

This paper presents a multi-component topology optimization method for the structural assemblies that are made of components produced by die casting (MTO-D) processes, where each part is guaranteed to be free from fully enclosed cavities and undercuts in the direction of mold drawing. Building upon our previous work on multi-component topology optimization for stamped sheet (MTO-S) metal assemblies, the proposed mathematical formulation incorporates new design variables specifying the parting line for each component. For each component, the structural elements are clustered into the core and cavity halves by using the parting line as a linear classifier for the point clouds represented by the density and membership values. The presence of undercut features and fully enclosed cavities are then evaluated for each mold half using the vector method with the numerically approximated density gradient. Several numerical examples on compliance minimization are presented to demonstrate the proposed method. The optimized results show that each part is indeed moldable with no undercut in the drawing direction and has no fully enclosed cavity. [ABSTRACT FROM AUTHOR]

Histone H3 K27M mutation is the defining molecular feature of the devastating pediatric brain tumor, diffuse intrinsic pontine glioma (DIPG). The prevalence of histone H3 K27M mutations indicates a critical role in DIPGs, but the contribution of the mutation to disease pathogenesis remains unclear. We show that knockdown of this mutation in DIPG xenografts restores K27M-dependent loss of H3K27me3 and delays tumor growth. Comparisons of matched DIPG xenografts with and without K27M knockdown allowed identification of mutation-specific effects on the transcriptome and epigenome. The resulting transcriptional changes recapitulate expression signatures from K27M primary DIPG tumors and are strongly enriched for genes associated with nervous system development. Integrated analysis of ChIP-seq and expression data showed that genes upregulated by the mutation are overrepresented in apparently bivalent promoters. Many of these targets are associated with more immature differentiation states. Expression profiles indicate K27M knockdown decreases proliferation and increases differentiation within lineages represented in DIPG. These data suggest that K27M-mediated loss of H3K27me3 directly regulates a subset of genes by releasing poised promoters, and contributes to tumor phenotype and growth by limiting differentiation. The delayed tumor growth associated with knockdown of H3 K27M provides evidence that this highly recurrent mutation is a relevant therapeutic target. [ABSTRACT FROM AUTHOR]

Abstract: Due to the remarkable enantioselective performances of polysaccharide derivatives, immobilized cellulose-based columns have high enantioseparation ability, which can be applied under various mobile phase conditions. In the present work, a cellulose-derived chiral stationary phase (CSP), namely Chiralpak IC was evaluated for enantioseparation of eight imidazole antifungal drugs (miconazole, econazole, isoconazole, sulconazole, butoconazole, fenticonazole, sertaconazole, and ketoconazole) in three mobile phase modes: normal-phase mode, polar organic mode and reversed-phase mode. The factors that affected the enantioseparation were investigated and optimized. Results indicated that the Chiralpak IC column possessed good enantioselectivity in three modes, with all analytes being successfully resolved. In addition, the mechanism of enantioseparation was preliminarily discussed based on the molecular structures and retention behavior of the enantiomers.Graphical Abstract: [ABSTRACT FROM AUTHOR]

In order to accelerate the optimization process of automotive seats, decrease the amount of computations, and realize forward design of seat performance, a simplified parametric model (SPM) is introduced in this paper during the optimization process of a school bus seat. The validity of the SPM of the seat and the feasibility of the modeling method are proved. The results calculated by the SPM show a good consistency with the shell element model. The SPM can also accurately reflect the deformation and stress of the seat in dynamic tests. Through mechanical analysis and energy analysis of the seat frame, the dynamic performance of the seat is improved to meet regulatory requirements. The SPM has the advantages of simple process, less number of units, time savings in modeling and calculation, and it provides the possibility to quickly analyze the performance of school bus seats and improve seat structure. [ABSTRACT FROM AUTHOR]

The current design and optimization of the occupant restraint system (ORS) are based on numerous actual tests and mathematic simulations. These two methods are overly time-consuming and complex for the concept design phase of the ORS, though they're quite effective and accurate. Therefore, a fast and directive method of the design and optimization is needed in the concept design phase of the ORS. Since the airbag system is a crucial part of the ORS, in this paper, a theoretical model for the vehicle airbag is established in order to clarify the interaction between occupants and airbags, and further a fast design and optimization method of airbags in the concept design phase is made based on the proposed theoretical model. First, the theoretical expression of the simplified mechanical relationship between the airbag's design parameters and the occupant response is developed based on classical mechanics, then the momentum theorem and the ideal gas state equation are adopted to illustrate the relationship between airbag's design parameters and occupant response. By using MATLAB software, the iterative algorithm method and discrete variables are applied to the solution of the proposed theoretical model with a random input in a certain scope. And validations by MADYMO software prove the validity and accuracy of this theoretical model in two principal design parameters, the inflated gas mass and vent diameter, within a regular range. This research contributes to a deeper comprehension of the relation between occupants and airbags, further a fast design and optimization method for airbags' principal parameters in the concept design phase, and provides the range of the airbag's initial design parameters for the subsequent CAE simulations and actual tests. [ABSTRACT FROM AUTHOR]

Pediatric high-grade glioma (HGG) is a devastating disease with a less than 20% survival rate 2 years after diagnosis. We analyzed 127 pediatric HGGs, including diffuse intrinsic pontine gliomas (DIPGs) and non-brainstem HGGs (NBS-HGGs), by whole-genome, whole-exome and/or transcriptome sequencing. We identified recurrent somatic mutations in ACVR1 exclusively in DIPGs (32%), in addition to previously reported frequent somatic mutations in histone H3 genes, TP53 and ATRX, in both DIPGs and NBS-HGGs. Structural variants generating fusion genes were found in 47% of DIPGs and NBS-HGGs, with recurrent fusions involving the neurotrophin receptor genes NTRK1, NTRK2 and NTRK3 in 40% of NBS-HGGs in infants. Mutations targeting receptor tyrosine kinase-RAS-PI3K signaling, histone modification or chromatin remodeling, and cell cycle regulation were found in 68%, 73% and 59% of pediatric HGGs, respectively, including in DIPGs and NBS-HGGs. This comprehensive analysis provides insights into the unique and shared pathways driving pediatric HGG within and outside the brainstem. [ABSTRACT FROM AUTHOR]

The time spending on modifying structures can be reduced if the vehicle crashworthiness performance optimisation is conducted using a conceptual or simplified computer-aided engineering (CAE) model at an early design stage. This paper uses a simplified CAE model to reduce the truck's stiffness. To represent the fully detailed CAE model, the simplified truck body model is built in the way that its total energy absorption and the buckling mode in each major component are the same as the detailed model during the frontal impact. Then, an optimisation analysis is conducted on the simplified model against the overall objectives of the truck crashworthiness, which are the survival space in the cab and the rebounded energy of the impactor. The objectives are divided into subobjectives of the frames, mounts and the energy absorber. Then, the cross sections of floor rails and energy absorber are designed based on the substructure's performance. In the end, the truck crashworthiness in ECE R29 regulations in the virtual test is improved substantially. The CAE-led design method shows advantages in the truck crashworthiness design. It can also be used in the early design of a new truck. [ABSTRACT FROM AUTHOR]

There has not been an effective method to measure the resistivity of small-size sample of mineral and solid insulating material until now. According to the Chinese National Standard (GB/T1410-2006) and features of digital high resistance meter, a small electrode experimental installation was developed; it can work with current high resistance meter; the sample decreases to 18 mm from standard size 100 mm in diameter and reduces by 30.86 times in area. A three-electrode system is supported and precisely positioned by two insulating bases whose diameter is 60 mm and height is 20 mm, which ensures accuracy of device structure and reliability of measuring results. The key technological parameters are as follows: diameter of high voltage electrode is 18 mm; diameter of measuring electrode is 14.6 mm; internal diameter and external diameter of guard electrode are 16 and 18 mm, respectively; the gap between guard electrode and measuring electrode is set at 0.6 mm. These parameters are adequate for the measurement of flat specimen of mineral and solid insulating material whose diameter is 18 mm. According to the confirmatory experiment on the volume resistivity and surface resistivity, the measuring results are almost the same, using a small electrode experimental installation and a standard electrode. [ABSTRACT FROM AUTHOR]

The mechanisms that regulate mammalian cell size during development and homeostatic maintenance are poorly understood. The tumor suppressor Pten is required for correct maintenance of mammalian neuronal soma size. Selective inactivation of/>ten in postnatal granule neurons of the cerebellum and dentate gyrus in mouse causes cell-autonomous hypertrophy as well as more complex phenotypes, including progressive macrocephaly, seizures, and premature death. To determine the contribution of rotor signaling to Pten-mediated growth regulation in the mammalian nervous system, we treated Pten conditional knockout mice with CCI-779, a specific rotor inhibitor, rotor inhibition decreased the seizure frequency and death rate in/>ten mutant mice, prevented the increase in Pten-deficient neuronal soma size in young mice, and reversed neuronal soma enlargement in adult mice. rotor inhibition did not decrease the size of wild-type adult neurons. Thus, rotor is required for neuronal hypertrophy downstream of Pten deficiency, but is not required for maintenance of normal neuronal soma size. roTOR inhibitors may be useful therapeutic agents for diseases in brain resulting from PTEN deficiency such as Lhermitte-Duclos disease or glioblastoma multiforme. [ABSTRACT FROM AUTHOR]

Somatic inactivation of PTEN occurs in different human tumors including glioblastoma, endometrial carcinoma and prostate carcinoma. Germline mutations in PTEN result in a range of phenotypic abnormalities that occur with variable penetrance, including neurological features such as macrocephaly, seizures, ataxia and Lhermitte-Duclos disease (also described as dysplastic gangliocytoma of the cerebellum). Homozygous deletion of Pten causes embryonic lethality in mice. To investigate function in the brain, we used Cre-loxPtechnology to selectively inactivate Pten in specific mouse neuronal populations. Loss of Pten resulted in progressive macrocephaly and seizures. Neurons lacking Pten expressed high levels of phosphorylated Akt and showed a progressive increase in soma size without evidence of abnormal proliferation. Cerebellar abnormalities closely resembled the histopathology of human Lhermitte-Duclos disease. These results indicate that Pten regulates neuronal size in vivo in a cellautonomous manner and provide new insights into the etiology of Lhermitte-Duclos disease. [ABSTRACT FROM AUTHOR]

To identify somatic mutations in pediatric diffuse intrinsic pontine glioma (DIPG), we performed whole-genome sequencing of DNA from seven DIPGs and matched germline tissue and targeted sequencing of an additional 43 DIPGs and 36 non-brainstem pediatric glioblastomas (non-BS-PGs). We found that 78% of DIPGs and 22% of non-BS-PGs contained a mutation in H3F3A, encoding histone H3.3, or in the related HIST1H3B, encoding histone H3.1, that caused a p.Lys27Met amino acid substitution in each protein. An additional 14% of non-BS-PGs had somatic mutations in H3F3A causing a p.Gly34Arg alteration. [ABSTRACT FROM AUTHOR]

The original article can be found online. [ABSTRACT FROM AUTHOR]

1,4-Dihydropyridine (DHP) scaffold holds an outstanding position with its versatile pharmacological properties among all heterocyclic compounds. Although most of the commercially available DHPs are marketed as a racemic mixture, the chiral center at C-4 can lead to even opposite pharmacological activities between the enantiomers. In the present study, enantioseparation of seventeen DHP structural analogues, consisting of either pharmacologically active or newly synthesized derivatives, (M2-4, MD5, HM2, HM10, CE5, N11, N10, N7, M11, MC6-8, MC13, MD23, and 42IIP) by high-performance liquid chromatography was investigated using immobilized polysaccharide-based chiral stationary phase, Chiralpak IC column. Due to the solvent versatility of the covalently immobilized chiral stationary phase in enantiomer separation, multiple elution modes including standard normal phase, nonstandard mobile phase, and reversed phase were used to expand the possibility to find the optimum enantioselective conditions for the tested analytes. Under appropriate separation conditions, complete enantiomeric separation was obtained for nearly all compounds except MC6-8 and MC13 which contained two chiral centers. Additionally, the effects of the polar modifier, the additive, and column temperature on the chiral recognition were evaluated. The thermodynamic parameters calculated according to the linear van't Hoff equation indicated that the chiral separations in this study were enthalpy-driven or entropy-driven. Some parameters of method validation such as linearity, limit of quantitation, and repeatability were also measured for all studied compounds to prove the reliability of the method. [ABSTRACT FROM AUTHOR]