Engineering osteoblastic metastases to delineate the adaptive response of androgen-deprived prostate cancer in the bone metastatic microenvironment

While stromal interactions are essential in cancer adaptation to hormonal therapies,the effects of bone stroma and androgen deprivation on cancer progression in bone are poorly understood.Here,we tissue-engineered and validated an in vitro microtissue model of osteoblastic bone metastases,and used it to study the effects of androgen deprivation in this microenvironment.The model was established by culturing primary human osteoprogenitor cells on melt electrowritten polymer scaffolds,leading to a mineralized osteoblast-derived microtissue containing,in a 3D setting,viable osteoblastic cells,osteocytic cells,and appropriate expression of osteoblast/osteocyte-derived mRNA and proteins,and mineral content.Direct co-culture of androgen receptordependent/ independent cell lines (LNCaP,C4-2B,and PC3) led cancer cells to display functional and molecular features as observed in vivo.Co-cultured cancer cells showed increased affinity to the microtissues,as a function of their bone metastatic potential.Cocultures led to alkaline phosphatase and collagen-I upregulation and sclerostin downregulation,consistent with the clinical marker profile of osteoblastic bone metastases.LNCaP showed a significant adaptive response under androgen deprivation in the microtissues,with the notable appearance of neuroendocrine transdifferentiation features and increased expression of related markers (dopa decarboxylase,enolase 2).Androgen deprivation affected the biology of the metastatic microenvironment with stronger upregulation of androgen receptor,alkaline phosphatase,and dopa decarboxylase,as seen in the transition towards resistance.The unique microtissues engineered here represent a substantial asset to determine the involvement of the human bone microenvironment in prostate cancer progression and response to a therapeutic context in this microenvironment.

Solid Mechanical and Hemodynamic Analyses of Different Stent Structures in a Curved Stenotic Coronary Artery

Background Coronary artery stenting is commonly used for the treatment of coronary atherosclerosis,but it causes serious clinical complications,such as the in-stent restenosis(ISR).The main reason leading to ISR is the neointimal hyperplasia(NH),which is related to the stresses of plaque and artery,and to the altered local hemodynamic environment due to the presence of stents.Different stent structures indeed have various impacts on the stresses of plaque and artery,and the local hemodynamic environment,such as the wall shear stress(WSS),average WSS(AWSS),and WSS gradient(WSSG).Thus,it is important to evaluate the performance of stents with different structures by the mechanical factors after coronary stenting.Methods Six stents implanted into a stenotic curved coronary artery were treated separately,and they included three typical commercial stents(Palmaz-Schatz,Xience,and Cypher)and three author-developed stents,which were constructed by reducing the numbers of link(C-Rlink)and crown(C-Rcrown),and aligning the strut(C-Astrut)of the commercial Cypher Solid mechanical analyses of the balloon-stent-plaque-artery system in Abaqus were first performed to assess the performance of different stent structures and provide the deformed boundary of lumen for the subsequent hemodynamic analysis.With the deformed boundary,then hemodynamic analyses in Ansys were conducted to quanti-fy the hemodynamic parameters induced by different stent structures.Combining the solid mechanical and hemodynamic analyses,the performance of the six stents was evaluated.Results The results show that among the three commercial stents,the Palmaz-Schatz stent has the least stent dogboning and recoiling,which corresponds to the greatest maximum plastic strain as well as the largest diameter.However,it induces the greatest maximum stress of plaque,intima,and media.From the viewpoint of hemodynamics,the Palmaz-Schatz stent also performs better and it has smaller areas of adverse low WSS(<0.5 Pa),high WSS(>15 Pa),low AWSS(<0.5 Pa),and high WSSG(>5 000 Pa/m).Compared to the commercial Cypher stent,the author-developed Cypher-based C-Rcrown and C-Astrut stents have smaller recoiling,greater maximum plastic stain and larger diameter,which indicates the improved mechanical performance of the Cypher stent.Moreover,both C-Rcrown and C-Astrut have smaller areas of adverse low WSS,high WSS,and low AWSS,but only C-Rcrown has smaller area of adverse high WSSG.Nevertheless,the C-Rlink stent is inferior to the commercial Cypher stent.In both senses of the solid mechanical and local hemodynamic analyses,the C-Rcrown stent is superior to the commercial Cypher stent and other Cypher-based stents.Conclusions In this study,solid mechanical and hemodynamic analyses were carried out to study the effects of six stents with different structures on their performances after stenting.It was found that the Palmaz-Schatz stent performed better than other two commercial stents,and the performance of the Cypher stent could be improved by reducing the number of crowns of its strut.The present study comparatively evaluates the performance of different stents inside a curved artery,and could be used as a guide to select a suitable commercial stent for clinical application,and provide a way to improve the performance of the existing commercial stents.

Optimization of Processing Parameters of Power Spinning for Bushing Based on Neural Network and Genetic Algorithms

A neural network model of key process parameters and forming quality is developed based on training samples which are obtained from the orthogonal experiment and the finite element numerical simulation. Optimization of the process parameters is conducted using the genetic algorithm (GA). The experimental results have shown that a surface model of the neural network can describe the nonlinear implicit relationship between the parameters of the power spinning process:the wall margin and amount of expansion. It has been found that the process of determining spinning technological parameters can be accelerated using the optimization method developed based on the BP neural network and the genetic algorithm used for the process parameters of power spinning formation. It is undoubtedly beneficial towards engineering applications.

Recent Advances in Fabrication and Characterization of Graphene-Polymer Nanocomposites

Graphene has attracted considerable interest over recent years due to its intrinsic mechanical, thermal and electrical properties. Incorporation of small quantity of graphene fillers into polymer can create novel nanocomposites with im- proved structural and functional properties. This review introduced the recent progress in fabrication, properties and potential applications of graphene-polymer composites. Recent research clearly confirmed that graphene-polymer na-nocomposites are promising materials with applications ranging from transportation, biomedical systems, sensors, elec-trodes for solar cells and electromagnetic interference. In addition to graphene-polymer nanocomposites, this article also introduced the synergistic effects of hybrid graphene-carbon nanotubes (CNTs) on the properties of composites. Finally, some technical problems associated with the development of these nanocomposites are discussed.

Thermal conduction of one-dimensional carbon nanomaterials and nanoarchitectures

This review summarizes the current studies of the thermal transport properties of one-dimensional(1D)carbon nano-materials and nanoarchitectures.Considering different hybridization states of carbon,emphases are laid on a variety of 1D carbon nanomaterials,such as diamond nanothreads,penta-graphene nanotubes,supernanotnbes,and carbyne.Based on experimental measurements and simulation/calculation results,we discuss the dependence of the thermal conductivity of these 1D carbon nanomaterials on a wide range of factors,including the size effect,temperature influence,strain effect,and others.This review provides an overall understanding of the thermal transport properties of 1D carbon nanomaterials and nanoarchitectures,which paves the way for effective thermal management at nanoscale.

Application of biocementation technique using Bacillus sphaericus for stabilization of soil surface and dust storm control

Dust emission and wind erosion are widespread phenomena in arid and semi-arid regions,which have far-reaching harmful effects to the environment.This study aimed to use microbial induced carbonate precipitation(MICP)method with Bacillus sphaericus to reduce soil losses that occur in a dust-producing area due to wind erosion in the Ilam Province,Iran.Soil samples at the 0-30 cm depth were used and sterilized in an autoclave for 2 h at 121℃ and 103 kPa.Approximately 3 kg soils were weighed and poured in the 35 cm×35 cm×3 cm trays.Different treatments included two levels of B.sphaericus(0.0 and 0.5 OD),three levels of suspension volume(123,264,and 369 mL),two levels of urea-chloride cementation solution(0.0 and 0.5 M),and two levels of bacterial spray(once and twice spray).After 28 d,soil properties such as soil mass loss,penetration resistance,and aggregate stability were measured.The results showed a low soil mass loss(1 g)in F_(14)formulation(twice bacterial spray+264 mL suspension volume+without cementation solution)and a high soil mass loss(246 g)in F_(5) formulation(without bacteria+264 mL suspension volume+0.5 M cementation solution).The highest(42.55%)and the lowest(19.47%)aggregate stabilities were observed in F_(16)and F_(7)formulations,respectively,and the highest penetration resistance(3.328 kg/cm^(2))was observed in F_(18) formulation.According to the final results,we recommended the formulation with twice bacterial spray,0.5 M cementation solution,and 269 mL suspension volume as the best combination for soil surface stabilization.Furthermore,this method is environmentally friendly because it has no adverse effects on soil,water,and plants,thus,it would be an efficient approach to stabilize soil surface.

Variable-based Ramberg-Osgood constitutive model of power spinning bushing

The influences of power spinning process parameters on the mechanical properties of spinning parts were analyzed with an SXD100/3-CNC numerical control power spinning machine.The unidirectional tensile tests were carried out.Based on the experimental data,a ternary quadratic regression equation was established by orthogonal experiment.The Ramberg-Osgood constitutive model of tin-bronze connecting rod bushing was obtained.Referred to the constitutive relation of macroscopic incremental,the incremental elastoplastic constitutive relation of spinning parts was deduced based on the Mises yield criterion and kinematic hardening model.The results can be applied to the elastoplastic analysis in finite element numerical simulation.

Earth-abundant amorphous catalysts for electrolysis of water

The generation of hydrogen through the electrolysis of water has attracted attention as a promising way to produce and store energy using renewable energy sources.In this process,a catalyst is very important to achieve a high‐energy conversion efficiency for the electrolysis of water.A good catalyst for water electrolysis should exhibit high catalytic activity,good stability,low cost and good scalability.Much research has been devoted to developing efficient catalysts for both the hydrogen evolution reaction(HER)and oxygen evolution reaction(OER).Traditionally,it has been accepted that a material with high crystallinity is important to serve as a good catalyst for HER and/or OER.Recently,catalysts for HER and/or OER in the electrolysis of water splitting based on amorphous materials have received much interest in the scientific community owing to the abundant unsaturated active sites on the amorphous surface,which form catalytic centers for the reaction of the electrolysis of water.We summarize the recent advances of amorphous catalysts for HER,OER and overall water splitting by electrolysis and the related fundamental chemical reactions involved in the electrolysis of water.The current challenges confronting the electrolysis of water and the development of more efficient amorphous catalysts are also discussed.

Recent progress on the prediction of two-dimensional materials using CALYPSO

In recent years, structure design and predictions based on global optimization approach as implemented in CALYPSO software have gained great success in accelerating the discovery of novel two-dimensional(2D) materials. Here we highlight some most recent research progress on the prediction of novel 2D structures, involving elements, metal-free and metal-containing compounds using CALYPSO package. Particular emphasis will be given to those 2D materials that exhibit unique electronic and magnetic properties with great potentials for applications in novel electronics, optoelectronics,magnetronics, spintronics, and photovoltaics. Finally, we also comment on the challenges and perspectives for future discovery of multi-functional 2D materials.

All-solid-state flexible asymmetric supercapacitors with high energy and power densities based on NiCo_2S_4@MnS and active carbon

Electrode material based on a novel core–shell structure consisting of NiCoS（NCS） solid fiber core and Mn S（MS） sheet shell（NCS@MS） in situ grown on carbon cloth（CC） has been successfully prepared by a simple sulfurization-assisted hydrothermal method for high performance supercapacitor. The synthesized NiCoS@Mn S/CC electrode shows high capacitance of 1908.3 F gat a current density of 0.5 A gwhich is higher than those of NiCoSand Mn S at the same current density. A flexible all-solid-state asymmetric supercapacitor（ASC） is constructed by using NiCoS@Mn S/CC as positive electrode, active carbon/CC as negative electrode and KOH/poly（vinyl alcohol）(PVA) as electrolyte. The optimized ASC shows a maximum energy density of 23.3 Wh kgat 1 A g, a maximum power density of about7.5 kw kgat 10 A gand remarkable cycling stability. After 9000 cycles, the ASC still exhibited67.8% retention rate and largely unchanged charge/discharge curves. The excellent electrochemical properties are resulted from the novel core–shell structure of the NiCoS@Mn S/CC electrode, which possesses both high surface area for Faraday redox reaction and superior kinetics of charge transport. The NiCoS@Mn S/CC electrode shows a promising potential for energy storage applications in the future.

Design of Supercapacitor Electrodes Using Molecular Dynamics Simulations

Electric double-layer capacitors(EDLCs) are advanced electrochemical devices for energy storage and have attracted strong interest due to their outstanding properties. Rational optimization of electrode–electrolyte interactions is of vital importance to enhance device performance for practical applications. Molecular dynamics(MD) simulations could provide theoretical guidelines for the optimal design of electrodes and the improvement of capacitive performances, e.g., energy density and power density. Here we discuss recent MD simulation studies on energy storage performance of electrode materials containing porous to nanostructures. The energy storage properties are related to the electrode structures, including electrode geometry and electrode modifications. Altering electrode geometry, i.e., pore size and surface topography,can influence EDL capacitance. We critically examine different types of electrode modifications, such as altering the arrangement of carbon atoms, doping heteroatoms and defects, which can change the quantum capacitance. The enhancement of power density can be achieved by the intensified ion dynamics and shortened ion pathway.Rational control of the electrode morphology helps improve the ion dynamics by decreasing the ion diffusion pathway. Tuning the surface properties(e.g., the affinity between the electrode and the ions) can affect the ionpacking phenomena. Our critical analysis helps enhance the energy and power densities of EDLCs by modulating the corresponding electrode structures and surface properties.

Nanoporous SiO_x coated amorphous silicon anode material with robust mechanical behavior for high-performance rechargeable Li-ion batteries

Silicon is a promising anode material for rechargeable Li-ion battery (LIB) due to its high energy density and relatively low operating voltage. However, silicon based electrodes suffer from rapid capacity degradation during electrochemical cycling. The capacity decay is predominantly caused by (i) cracking due to large volume variations during lithium insertion/extraction and (ii) surface degradation due to excessive solid electrolyte interface (SEI) formation. In this work, we demonstrate that coating of a-Si thin film with a Li-active, nanoporous SiOx layer can result in exceptional electrochemical performance in Li-ion battery. The SiOx layer provides improved cracking resistance to the thin film and prevent the active material loss due to excessive SEI formation, benefiting the electrode cycling stability. Half-cell experiments using this anode material show an initial reversible capacity of 2173 mAh g^-1 with an excellent coulombic efficiency of 90.9%. Furthermore, the electrode shows remarkable capacity retention of ~97% after 100 cycles at C/2 charging rate. The proposed anode architecture is free from Liinactive binders and conductive additives and provides mechanical stability during the charge/discharge process.

In-situ growth of nanowire WO_(2.72) on carbon cloth as a binder-free electrode for flexible asymmetric supercapacitors with high performance

For the first time,WO_(2.72) nanowires were in-situ grown on carbon cloth by a simple solvothermal reaction.The nanowire WO_(2.72)/carbon cloth(NW WO_(2.72)/CC) electrode showed good electrochemical performance with specific capacitance(C_s) reaching up to 398 F g^(-1) at a current density of 2 A g^(-1).The capacitance of 240 F g^(-1) was retained at a high current density of 16 A g^(-1).To further evaluate the energy storage performance,flexible asymmetric supercapacitors(FASC_s) were fabricated using the activated carbon/carbon cloth(AC/CC) as negative electrode and NW WO_(2.72)/CC as positive electrode,respectively.The FASC_s delivered a high energy density of 28 Wh kg^(-1) at a power density of 745 W kg^(-1) and 13 Wh kg^(-1) even at a high power density of 22.5 k W kg^(-1).More impressively,81% of the specific capacitance of the FASC_s was retained after 10,000 cycles,indicating excellent cycle stability.This work indicates the NW WO_(2.72)/CC holds a great potential for application in energy storage devices.

Flexible quasi-solid-state dual-ion asymmetric supercapacitor based on Ni（OH）2 and Nb2O5 nanosheet arrays

Increasing the energy density, power density as well as widening the operation voltage are essential to electrochemical capacitors to meet the practical energy demands. Herein, a novel flexible quasi-solid-state dual-ion asymmetric supercapacitor(ASC) with Ni(OH)2 and Nb2O5 nanosheets directly grown on stainless steel mesh is developed. In the dual-ion ASC, Nb2O5 negative and Ni(OH)2 positive electrodes react with Li+ and OH- respectively in alkaline gel electrolyte to store energy, which is quite different from conventional alkali metal ion SCs and alkaline SCs. The as-assembled flexible device has an extended working voltage of 1.7 V and delivers a capacity of 5.37 mAh cm-2, a maximum energy density and power density of 0.52 mWh cm-3 and 170 mW cm-3 , respectively. The device maintains around 60% capacity retention after long cycling up to 1000 cycles. Moreover, our device can light up a LED light efficiently upon fast charging. The proposed quasi-solid-state dual-ion ASC has potential applications in future portable electronics and flexible energy storage devices.

A meshfree-based local Galerkin method with condensation of degree of freedom for elastic dynamic analysis

Condensation technique of degree of freedom is first proposed to improve the computational efficiency of meshfree method with Galerkin weak form for elastic dy- namic analysis. In the present method, scattered nodes with- out connectivity are divided into several subsets by cells with arbitrary shape. Local discrete equation is established over each cell by using moving Kriging interpolation, in which the nodes that located in the cell are used for approxima- tion. Then local discrete equations can be simplified by con- densation of degree of freedom, which transfers equations of inner nodes to equations of boundary nodes based on cells. The global dynamic system equations are obtained by as- sembling all local discrete equations and are solved by using the standard implicit Newmark＇s time integration scheme. In the scheme of present method, the calculation of each cell is carried out by meshfree method, and local search is imple- mented in interpolation. Numerical examples show that the present method has high computational efficiency and good accuracy in solving elastic dynamic problems.

Improving the performance of arylamine-based hole transporting materials in perovskite solar cells： Extending π-conjugation length or increasing the number of side groups？

In this work, we prepared three simple arylamine-based hole transporting materials from commercially available starting materials. The effect of extending z-conjugation length or increasing the number of side groups compared with reference compound on the photophysical, electrochemical, hole mobility properties and performance in perovskite solar cells were further studied. It is noted that these two kinds of molecular modifications can significantly lower the HOMO level and improve the hole mobility, thus improving the hole injection from valence band of perovskite. On the other hand, the compound with more side groups showed higher hole injection efficiency due to lower HOMO level and higher hole mo- bility compared with the compound with extending π-conjugation length. The perovskite solar cells with the modified molecules as hole transporting materials showed a higher efficiency of 15.40% and 16.95%, respectively, which is better than that of the reference compound （13.18%）. Moreover, the compound with increasing number of side groups based devices showed comparable photovoltaic performance with that of conventional spiro-OMeTAD （16.87%）.

Influence of Structural Parameters of Turbocharger Floating Bearing on Its Dynamic Characteristic Coefficients

The structure parameters in an actual industrial production have a great influence on the coefficient of supercharger floating bearing dynamic characteristics,but there has been little systematic study so far.In this paper,the influence of structural parameters of the turbocharger floating bearing on its dynamic characteristic coefficientsis systematically investigated based on the theories of hydrodynamic lubrication and tribology.The influence of clearance ratio on eccentricity and the influence of internal to external radius ratios,and Sommerfeld number were analyzed.A new formula of responding characteristics of the oil film force caused by the displacement or velocity disturbance was deduced near an equilibrium in the steady state.Applying the newly developed formula,the dynamic characteristic was studied for floating bearings.Regularity for change of oil film stiffness and damping was analyzed with the structural parameters of floating bearing such as radius ratios and eccentricity.It has been found that the clearance ratio increases with eccentricity when the radius ratio is unchanged.The eccentricity decreases with the internal to external radius ratio of floating rings when the clearance ratio is constant.The absolute value of total principal stiffness and total main damping decrease with the clearance ratio and radius ratio of floating rings when the total cross damping is stable.The results and findings in this paper can contribute to nonlinear dynamics designs of turbocharger rotor-bearing systems.

Stress relaxation analysis of single chondrocytes using porohyperelastic model based on AFM experiments

Based on atomic force microscopy technique, we found that the chon- drocytes exhibits stress relaxation behavior. We explored the mechanism of this stress relaxation behavior and concluded that the intracellular fluid exuding out from the cells during deformation plays the most important role in the stress relax- ation. We applied the inverse finite element analysis technique to determine nec- essary material parameters for porohyperelastic （PHE） model to simulate stress relaxation behavior as this model is proven capable of capturing the non-linear behavior and the fluid-solid interaction during the stress relaxation of the single chondrocytes. It is observed that PHE model can precisely capture the stress re- laxation behavior of single chondrocytes and would be a suitable model for cell biomechanics.

Nanostructured Graphene Surfaces Promote Different Stages of Bone Cell Differentiation

Nanostructured graphene films were used as platforms for the differentiation of Saos-2 cells into bonelike cells. The films were grown using the plasma-enhanced chemical vapor deposition method, which allowed the production of both vertically and horizontally aligned carbon nanowalls(CNWs). Modifications of the techniqueallowed control of the density of the CNWs and their orientation after the transfer process. The influence of two different topographies on cell attachment, proliferation,and differentiation was investigated. First, the transferred graphene surfaces were shown to be noncytotoxic and were able to support cell adhesion and growth for over 7 days.Second, early cell differentiation(identified by cellular alkaline phosphatase release) was found to be enhanced on the horizontally aligned CNW surfaces, whereas mineralization(identified by cellular calcium production), a later stage of bone cell differentiation, was stimulated by the presence of the vertical CNWs on the surfaces. These results show that the graphene coatings, grown using the presented method, are biocompatible. And their topographies have an impact on cell behavior, which can be useful in tissue engineering applications.

The Influence of Abrasive Pretreatment on Hot Air Drying of Grape

The drying of grapes is a more complex process compared to the dehydration of other agricultural materials due to the necessity of a pretreatment operation prior to drying. Grape drying to produce raisins is a very slow process, due to the peculiar structure of grape peel, that is covered by a waxy layer. Its removal has been so far carried out by using several chemical pre-treatments. However, they cause heterogeneity in the waxes removal and create microscopic cracks. In this paper an abrasive pretreatment for enhancing the drying rate and preserving the grape samples is proposed. Two cultivars of grape were investigated: Regina white grape and Red Globe red grape. The drying kinetics of untreated and treated samples were studied using a convective oven at 50°C. Fruit quality parameters such as sugar and organic acid contents, shrinkage, texture, peel damage (i.e. by SEM analysis) and rehydration capacity were studied to evaluate the effectiveness of abrasive pretreatment on raisins. Abrasive pretreatment contributed to reduce drying time and rehydration time. The treated and untreated dried grapes were significantly different (p < 0.05) in sugar and in tartaric acid content. On the contrary, no significant differences (p < 0.05) in malic and citric acids and in texture properties between untreated and treated samples were observed.