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Cheating is widespread in online games, particularly in competitive games, such as first-person shooter (FPS) games. One of the most common types of cheating is extrasensory perception (ESP), which involves illicitly obtaining visual information to gain an unfair advantage over normal players. To protect the gaming experience of legitimate players and the interests of game companies, there is an urgent need for anticheating applications. In this article, we propose a general system for ESP anticheating in online FPS games, considering the business characteristics and industrial applications. We present a vision-based anticheating framework that incorporates both supervised and unsupervised solutions for comprehensive cheating detection. Based on this framework, we design and deploy a dual-audit human-in-the-loop system for industrial gaming anticheating applications. We evaluate our proposed framework from multiple online and offline perspectives and demonstrate its practical significance with superior performance.

Thermosetting epoxy resins are frequently restricted by their inferior toughness, nonprocessability, and nonrecyclability resulting from their permanently cross-linked molecular network structure and the rigidity of their molecular chains, limiting the promotion of their additional value. Based on our previous research on the hindered urea bonds (HUBs), herein, we incorporated HUBs with isocyanates into the traditional epoxy network, synthesizing epoxy-based polyurea, namely, EHTPUs. The EHTPUs were synthesized by using commercial raw materials containing HDI-trimers, 2,6-dimethyl piperazine, and difunctional epoxides (E44 or PPGE) without a catalyst. By modulation of the proportion of epoxy monomers, these synthetic EHTPUs exhibit adjustable mechanical behavior, transitioning from soft elastomers to hard plastics. The dynamic HUBs can endow these EHTPUs with excellent recyclability, where their mechanical properties can be fully recovered (above 90%) after four cycles, elevating the versatility and long-term lifespan. Importantly, their dynamic mechanical properties, solvent resistance, and transmittance also can remain stable after four cycles. Meanwhile, the EHTPUs possess elastic shape memory and a 3D permanent shape reconfiguration capability in the same sample. Our work provides a fascinating way to design adjustable mechanical properties, recyclability, and multifunctionality thermosetting epoxy-based polymers, accelerating this category of recyclable polymers toward application and functionalization.

Abstract: Soil pore is a key attribute of the soil structure that affects soil reservoir under natural vegetation recovery on the Loess Plateau. This study is to quantitatively analyze soil pore parameters, measured with Computed Tomography (CT) at 15–57 mm depths under five different vegetation succession stages using a concept of substituting “space” for “time” in the Ziwuling Forest Region of the Loess Plateau. The results showed that the soil pore parameters, such as pore number, porosity, circularity, and fractal dimension, increased significantly under the natural vegetation successions and varied with the pattern climax community stage>pioneering arbor community stage>scrub community stage>herbaceous community stage>abandoned farmland stage, indicating that natural vegetation recovery could remarkably improve soil pore characteristics. With the vegetation succession, this positive effect will be strengthened gradually, which means that the soil pore parameters may appear to be best at the climax community stage. Soil organic matter content increased linearly with the soil pore parameters (P<0.001). Increased organic matter accumulation was one of the major reasons for the changes in soil pore characteristics in natural vegetation succession.

To solve the asymmetric problems of each phase caused by the different relative positions of the armature coils and excitation sources (PMs and excitation coils) in traditional three-phase hybrid-excited doubly salient generator (HEDSG), a novel HEDSG with long pitch field sources is proposed in this paper. Because of the adoption of excitation winding wound around the PMs sandwiched “four-teeth”, the symmetric magnetic circuits among phases can be achieved, thus the balanced three-phase back electromotive force (EMF) curves can be obtained. First, the configuration of proposed HEDSG is described, based on which its operation principle is discussed from the perspective of magnetic circuits. Besides, the flux regulation principle is analyzed based on the simplified equivalent magnetic circuit model. Then, a multi-step design optimization method is implemented to determine optimal structural parameters. Whereafter, the effect of the bidirectional excitation on the static and dynamic performances of the proposed HEDSG is investigated, which demonstrates it has a strong flux regulation ability. Furthermore, a comparative study between the proposed and traditional HEDSGs is conducted. It is shown that the proposed HEDSG can essentially solve the asymmetric problem among phases and possesses the merits of lower cogging torque and higher output power. Finally, a prototype of the proposed HEDSG is fabricated and tested so as to experimentally verify the analysis and simulation.

DC microgrid (DCMG) is characterized by a high degree of power electronics, low system inertia, and CPL (CPL) with a negative damping feature. Its system-level transient stability is of great concern. The stability of a DCMG system is affected by many factors, such as component parameters, load types, converter control methods, etc. To analyze the system-level stability of the DCMG, the constraints of large signal stability of the DCMG based on droop control are derived by using the Lyapunov direct method. Based on this conclusion, the influence of system parameters on large signal stability and voltage deviation of the DCMG is revealed, and the optional range of filter element parameters and droop coefficient under the stability and voltage constraints is proposed. The parameter selection work involves two evaluation indicators, system stability, and voltage deviation. This article uses the variable weight coefficient method to normalize these two indicators into a comprehensive evaluation index, and the appropriate droop coefficient is selected based on the optimal comprehensive evaluation index. The work of this article has reference values for the parameter design of the DCMG system components and the selection of the droop coefficient.

To realize the online observation of the flux linkage of interior permanent magnet (PM) synchronous machine for electric vehicles after uniform demagnetization under multiple operating conditions, an improved model reference adaptive system (MRAS) flux linkage observer is proposed based on a novel double closed-loop control approach in this article. First, a double closed-loop control strategy of interior permanent magnet synchronous motor (IPMSM) is established employing maximum torque per ampere (MTPA) and sliding mode controller (SMC). The MTPA significantly improves the current utilization and system efficiency, and the SMC is applied to replace the traditional PI velocity loop controller to increase the anti-interference capability of the whole system. Then, the MRAS and single neuron adaptive proportional integral (SNPI) algorithm are adopted to develop an SNPI-MRAS flux linkage observer, which can modify the adaptive law of the MRAS online and overcome the shortage of low observation accuracy of traditional PI-MRAS flux observer when the machine parameters change. Next, a feedback gain matrix term is inserted in the SNPI-MRAS, which can guarantee that the linear forward channel of the SNPI-MRAS is a strictly positive real matrix. Finally, the effectiveness of the proposed method is verified. The outcomes demonstrate that the proposed method can effectively improve the dynamic response of the observer and increase its accuracy and convergence speed.

Phase change materials (PCMs) that can effectively improve the efficiency of energy storage and conversion have been used in the field of microelectronic devices for prolonging service life. However, conventional PCMs are easy to cause brittle fractures and damage to microelectronic devices because of their strong rigidity, which cannot perfectly fit the irregular surface of microelectronic devices. Herein, we successfully synthesized a dynamic covalently cross-linked shape memory PCM (HPCM8K) with polyethylene glycol (PEG) as the phase change component, hexamethylene diisocyanate trimer as the crosslinking point, and a disulfide bond as the dynamic covalent bond. The tensile strength and the elongation at break of the designed HPCM8K-1 can reach 27.7 MPa and 853.1%, respectively; meanwhile, HPCM8K has excellent latent heat storage capacity with the highest latent heat of 98.1 J/g. Importantly, these HPCM8K can integrate both traditional elastic shape memory and permanent shape reconstruction capabilities into one PEG-based dynamic cross-linking network after introducing the disulfide bond in the molecular structure. The key point of this work is to introduce exceptional mechanical performance and remarkable shape memory ability into PCMs, greatly improving the operability of shape change and enhancing their shape adaptability for accommodating different surfaces of microelectronic devices.

ABSTRACTWe investigated the effect of different fat sources on growth performance and intestinal health in weaned piglets. A total of 72 21-day-old weaned piglets were divided into 3 groups the CON group with 2.5% soybean oil, TRE1 with 2.5% emulsified balanced oil powder and TRE2 with 2.5% emulsified coconut oil powder. These two experimental oil powders were emulsified with the emulsifier (lysophospholipid). The average daily feed intake in TRE1 was significantly higher than that in CON (P< 0.05). The apparent total tract digestibility (ATTD) of ash in TRE1 was significantly higher than that in CON (P< 0.05). Compared with CON, TRE1 tended to improve ATTD of dry matter (P= 0.075), serum triglyceride (P= 0.062) and serum-free fatty acids (P= 0.090). The jejunal villus width of piglets in TRE1 and TRE2 was significantly increased (P< 0.05) and the duodenal crypt depth was significantly decreased (P< 0.05). Compared with CON, TRE1 significantly increased the mRNA expression levels of jejunal Occludin, Claudin-1 and ZO-1 (P< 0.05). From the results of the present study, we concluded that dietary supplementation of 2.5% emulsified balanced oil powder has more obvious effects on enhancing the growth performance of weaned piglets by improving lipid metabolism, intestinal tissue development and barrier function.

Online gaming is a multibillion dollar industry that entertains a large, global population. Empowering online games with AI has made a great success, however, ignores the explainability of black-box model makes AI less responsible and hinders its further development. In this article, we introduce and discuss the audience and the concept of XAI (eXplainable AI) in online games. We propose a GXAI workflow, which combines the strong expressiveness of multiview data sources and the clear transparency of multiview black-box models. We present four specific classifiers and explainers in the character portrait view, the behavior sequence view, the client image view, and the social graph view. Experiments conducted on real-world datasets for game cheating detection and player churn prediction show the accuracy of classification and the rationality of explanation. We also discover and present numerous interesting and valuable findings from the individual, local, and global explanations. We implement and deploy three practical applications, including evidence and reason generation, model debugging and testing, and model compression and comparison in NetEase Games and have received quite positive reviews from user studies. More future work is in progress since this is the first work that introduces XAI in online games.

Soil interparticle forces can pose important effects on soil aggregate stability and rainfall splash erosion. Meanwhile, these interparticle forces are strongly influenced by specific ion effects. In this study, we applied three monovalent cations (Li+, Na+, and K+) with various concentrations to investigate the influence of specific ion effects on aggregate stability and splash erosion via pipette and rainfall simulation methods. The specific ion effects on soil interparticle forces were quantitatively evaluated by introducing cationic non-classical polarization. The results showed that aggregate stability and splash erosion had strong ion specificity. Aggregate breaking strength and splash erosion rate at the same salt concentration followed the sequence as Li+ > Na+ > K+. With decreasing salt concentration, the difference in aggregate breaking strength or splash erosion rate between different cation systems increased initially (1–10–2 mol L–1) and later was nearly invariable (10–2–10–4 mol L–1). The experimental results were well quantitatively explained by soil interparticle forces considering cationic non-classical polarization. Furthermore, both aggregate breaking strength and splash erosion rate of three cations revealed a strong positive linear relation with net force subjected to cationic non-classical polarization (R2 = 0.81, R2 = 0.81). These results demonstrated that different non-classical polarization of cations resulted in different soil interparticle forces, and thus led to differences in aggregate stability and splash erosion. Our study provides valuable information to deeply understand the mechanisms of rainfall splash erosion.

AbstractGranular-continuum interfaces commonly exist in geotechnical engineering practices, such as foundations, reinforcements, and soil nailing. The mechanical behaviors and fabric of the interface are not only influenced by the soil properties but the interfaces, and normal stresses. Therefore, a thorough understanding of the granular-continuum interface is essential to engineering practices. This article investigates the interface shear behavior focusing on the normal stresses and soil densities by using the three-dimensional discrete element modeling (DEM). The influence zones resulting from counterface mobilization vary with the normal stresses and soil densities. The interface shearing problem physics obtained from DEM have been demonstrated to be consistent with the experiments. Based on the DEM model, the evolution of the micromechanical behaviors and fabric for the immediate influence zone of the interface at both failure and the critical state are investigated, such as fabric anisotropy, sliding fraction, and mechanical coordination number. The stress tensor and fabric tensor, determined from the granular assembly in the influence zone, are used to capture the interface shear strength. Results show that, due to the evolution of particle interlock and dilation, both the macro and micro mechanical parameters decrease mostly with the increasing confining stress at both failure and the critical state.

The presence of keyhole-induced porosity significantly limits the application of laser powder bed fusion (L-PBF) in the additive manufacturing industry. Typically, a trial-and-error approach is used to select the best printing strategies for material type, powder bed, and laser beam to optimize the manufacturing process. This paper proposes an optimization strategy that uses adaptive laser power based on key understanding of the physical mechanisms of keyhole fluctuations. We identify and analyze five stages of the keyhole pore formation process, including the "J"-like keyhole formation, keyhole closure, keyhole pore collapse, keyhole pore splitting, and keyhole pore motion. Our simulation results suggest that reducing the laser power at the onset of "J"-like keyhole formation is an appropriate optimization approach. We propose adaptive indices to quantify keyhole fluctuations and predict the onset of "J"-like keyhole formation, which facilitates the use of adaptive laser power for optimization. Two parametric studies are conducted to investigate the impact of the optimization criterion and laser power adjustment on keyhole instability. The results demonstrates that our optimization strategy can effectively stabilize the keyhole and reduce the occurrence of keyhole porosity.

In this paper, a new reconfigurable power divider (PD) is proposed to improve the efficiency of the three-way Doherty power amplifier (DPA). The conventional λ/4 transmission line is replaced by the proposed reconfigurable PD in the input of peaking amplifier, where the 90° phase shift and impedance matching can be achieved. Furthermore, the output power distribution ratio (PDR) can be continuously adjusted in a large range by adjusting the reverse voltage of the varactor diodes. Therefore, the reconfigurable PD with the best PDR can assign input power to the peaking amplifier. Experiment results show that the maximum measured power added efficiency (PAE) of the proposed three-way DPA is 49%, which is improved by 5% compared with conventional three-way DPA.

In this study, a series of bentonite-carbide slag (BCS) mineral composites were developed by modifying bentonite with carbide slag using Na2CO3as activator, to achieve acid neutralization and mineralized immobilization of Cu2+in acid mine drainage (AMD). The main factors that affect the structure-activity relationship of the BCS particle, such as material ratio, Na2CO3dosage, calcination temperature, and calcination time, were investigated in detail to determine the influence rules of each factor and the structure-activity relationship of the BCS particle on the immobilized mineralization of Cu2+via spontaneous film formation. The results indicated that the optimal preparation parameters for BCS particle were as follows: bentonite/carbide slag mass ratio of 3:7, Na2CO3amount of 10 wt%, calcination temperature of 500℃ and calcination time of 60 min. During the calcination process, Na2SiO3and C-S-H were formed under the action of the Na2CO3activator, which were conducive to bonding between the raw material in BCS particle. The mechanism of OH-alkalinity release of endophytic crystal ions in BCS particle, and the mechanism of spontaneous film formation and immobilization mineralization of Cu2+in AMD were also proposed with the help of SEM, XRD and FT-IR analysis. This study can provide theoretical guidance for the preparation of composite mineral particle material with endophytic crystal ions, as well as the prevention and control of AMD and the recovery of valuable metals from AMD.

The residue of ofloxacin in animal derived food would seriously affect human health. This study reports an inexpensive, fast, and simple electrochemical sensor for the sensitive detection of OFL in animal derived food samples. A poly-L-glutamic acid/poly(sulfobutyl-β-cyclodextrin) CdTe quantum dot-modified electrode P(L-Glu)/SEB-β-CD@CdTeQDs/GCE was prepared by an electrochemical polymerization reaction. We investigated the electrochemical behavior of OFL on the sensing electrode by cyclic voltammetry and square wave voltammetry. The results showed that the sensitivity of the sensor was significantly improved under the synergistic effect of L-glutamic acid, sulfobutyl-β-cyclodextrin, and CdTe quantum dots. In addition, the electrochemical reaction process of OFL on the sensing electrode was investigated and the results showed that the transfers of two protons and two electrons were involved in the reaction. Subsequently, the electrochemical sensing method based on P(L-Glu)/SEB-β-CD@CdTeQDs/GCE was developed and validated for the determination of OFL, showing a good linear response in the range of 0.07 ∼ 1 μg·ml−1with a detection limit of 3.4 ng·ml−1, and the precision and accuracy were high enough. Compared with the conventional HPLC method, the established electrochemical sensing method shows the merits of being eco-friendly, shorter detection time and being much more simple, sensitive, and convenient.

Development of schemes to form complex three-dimensional (3D) mesostructures in functional materials is a topic of broad interest, thanks to the ubiquitous applications across a diversity of technologies. Recently established schemes in the mechanically guided 3D assembly allow deterministic transformation of two-dimensional structures into sophisticated 3D architectures by controlled compressive buckling resulted from strain release of prestretched elastomer substrates. Existing studies mostly exploited supporting substrates made of homogeneous elastomeric material with uniform thickness, which produces relatively uniform strain field to drive the 3D assembly, thus posing limitations to the geometric diversity of resultant 3D mesostructures. To offer nonuniform strains with desired spatial distributions in the 3D assembly, this paper introduces a versatile set of concepts in the design of engineered substrates with heterogeneous integration of materials of different moduli. Such heterogeneous, deformable substrates can achieve large strain gradients and efficient strain isolation/magnification, which are difficult to realize using the previously reported strategies. Theoretical and experimental studies on the underlying mechanics offer a viable route to the design of heterogeneous, deformable substrates to yield favorable strain fields. A broad collection of 3D mesostructures and associated heterogeneous substrates is fabricated and demonstrated, including examples that resemble windmills, scorpions, and manta rays and those that have application potentials in tunable inductors and vibrational microsystems.

Piglet formula is an important substitute for piglets when sow milk is unavailable. Triacylglycerols (TAGs) are the major components of sow milk and formulas. Lipolysis of TAGs in sow milk and five piglet formulas, mainly PF1 containing high similarity of sow milk fat substitute, PF2 containing coconut oil, and PF3-PF5 containing different amounts of 19.7%∼38.5% of medium chain fatty acids, was studied using in vitro dynamic gastrointestinal digestion system of piglets, and to elucidate the mechanism on digestive behaviors affected by different types of fats. The results showed that sow milk exhibited the largest particle size (4.22 μm) and the lowest absolute zeta-potential (12.8 mV) compared with formulas, contributing to its highest lipolysis degree (60.6%). It was followed by PF1 (56.2%), which had a similar fat composition to sow milk, especially the high content of sn-2 C16:0. Similarly, sow milk released the highest level of free fatty acids (56.9%, mainly long-chain species) after digestion, followed by PF1 (54.2%), and the other three formulas (33.8%–50.7%). The releases of diacylglycerides (e.g., L/L, P/L, P/O, O/O, and O/L) and monoacylglyceride-C16:0 were positively correlated with sn-2 C16:0 concentration, and the later will be re-esterified and reutilized for providing energy and essential fatty acids to piglets. It was indicated that the difference of fat digestive behaviors between sow milk and piglet formulas was associated to fat compositions and interfacial properties of their fat droplets. In this regard, digestion of fats for piglet formulas contributes to improving piglet health.

Polymeric photothermal phase change material composite (PPCMC) networks with excellent reprocessability, high latent heat, and intrinsic network stability have the great advantages of solar energy storage and conservation and environmental protection resulting from the covalent crosslinking network structure and long-life inorganic photothermal agents. Herein, the reprocessable PPCMCs were successfully prepared by introducing the reactive diisocyanate-terminated poly(ethylene glycol) (PEG) and multiple amino-functionalized carbon black (CB)that serve as the phase change component and the photothermal curing agent, respectively. The phase change properties, mechanical strength, and photothermal efficiency of PPCMCs can be tuned by the chain length of PEG and the loading content of CB and the catalyst. PPCMCs possess the largest latent heat of 126.7 J/g, the highest photothermal conversion efficiency of 89.0%, superior shape stability even at 140 °C, high thermal stability beyond 300 °C, and reprocessing ability by introducing the catalyst of the transcarbamoylation reaction. Also, the PPCMCs exhibit high thermal reliability after accelerated thermal cycling and reprocessing, featuring nearly consistent chemical and crystalline structures, latent heat, phase change temperature, and photothermal properties. This synthetic strategy provides an alternative to obtain multi-functional PPCMCs due to the enhanced interfacial interaction between inorganic particles and the polymer matrix via covalent linkages.

Sirt 1 plays a critical role in stress responses. We determined the deregulation of Sirt 1 activity, p53 acetylation, Bcl-2 expression, and mitochondria-dependent apoptosis in mouse osteoblast MC3T3-E1 cells which were exposed to H2O2. And then we investigated the protective role of Sirt 1 activator, Resveratrol (RSV), against the H2O2-induced apoptosis. Results demonstrated that Sirt 1 and Bcl-2 were inhibited, whereas p53 acetylation, Bax, and caspase 9 were promoted by H2O2, as was aggravated by the Sirt 1 inhibitor, EX-527. Instead, RSV inhibited the H2O2-induced both p53 acetylation and the caspase 9 activation, whereas ameliorated the H2O2-induced Bcl-2 inhibition and apoptosis. In conclusion, Sirt 1 was downregulated during the H2O2-induced apoptosis in MC3T3-E1 cells. And the chemical activation of Sirt 1 inhibited the H2O2-induced apoptosis via the downregulation of p53 acetylation. Our results suggest that Sirt 1 upregulation appears to be an important strategy to inhibit the oxidative stress-induced apoptosis.

Effects of five different breeds (Landrace × Large White, Landrace, Large White, Duroc and Pietrain) and two lactation stages (colostrum and milk) on phospholipids and their fatty acids compositions, cholesterol, and tocopherols in sow milks (n = 100) were investigated in the present study. Six classes of phospholipids were identified using 31P NMR spectroscopy, with the total phospholipid levels ranging from 56.84 to 151.02 μmol/100 mL. Sphingomyelin (SM) was the most abundant phospholipids (33.57%–48.00%) in both colostrum and milk. Colostrum contained higher percentages of SM, phosphatidylserine (PS), phosphatidylinositol (PI), and ethanolamine plasmalogen (EPLAS) than those in milk, while milk contained higher percentages of phosphatidylcholine (PC), and phosphatidylethanolamine (PE). C16:0 and C18:0, accounting for more than 80% of the saturated fatty acids of phospholipids in both colostrum and milk, decreased throughout the lactation. The average cholesterol concentration in colostrum was 430.60 mg/100 g fat, which was significantly lower than that in milk (646.44 mg/100 g fat). α-Tocopherol levels in Landrace × Large White breed were 38.35 and 15.91 mg/100 g fat in colostrum and milk, respectively, which were significantly higher than other breeds; while no significant variations in β-, γ-, and δ-tocopherols were noted among different breeds. The results demonstrated that lactation stages and breeds were mainly responsible for the significant differences of phospholipids, cholesterol, and tocopherols, providing a theoretical guidance for the manufacture of commercial formula of piglets.

The effects of heavy ion irradiation on the electrical response of HfO2-based ferroelectric capacitors have been studied. All the hysteresis loops measured from the irradiated samples shifted toward the positive voltage. The remanent polarization and relative permittivity of the capacitors decrease with increasing ion fluence. The leakage current exhibit negligible change after irradiation. The main reason causing the phenomena is swift heavy ions (SHIs) induced the pinning of domain walls, attributed to the phase transition. This work provides the possible physical mechanisms of SHIs irradiation on HfO2-based ferroelectrics, which is of significance for the space application of HfO2-based ferroelectric random access memory.

Abstract: Soil pore is a key attribute of the soil structure that affects soil reservoir under natural vegetation recovery on the Loess Plateau. This study is to quantitatively analyze soil pore parameters, measured with Computed Tomography (CT) at 15–57 mm depths under five different vegetation succession stages using a concept of substituting “space” for “time” in the Ziwuling Forest Region of the Loess Plateau. The results showed that the soil pore parameters, such as pore number, porosity, circularity, and fractal dimension, increased significantly under the natural vegetation successions and varied with the pattern climax community stage>pioneering arbor community stage>scrub community stage>herbaceous community stage>abandoned farmland stage, indicating that natural vegetation recovery could remarkably improve soil pore characteristics. With the vegetation succession, this positive effect will be strengthened gradually, which means that the soil pore parameters may appear to be best at the climax community stage. Soil organic matter content increased linearly with the soil pore parameters (P<0.001). Increased organic matter accumulation was one of the major reasons for the changes in soil pore characteristics in natural vegetation succession.

To alleviate the predicament of resource shortage and environmental pollution, efficiently using abundant solar energy is a great challenge. Herein, we prepared unique photothermal conversion phase-change materials, namely, CNT@PCMs, by introducing carbon nanotubes (CNTs) used as photothermal conversion materials into the recyclable matrix of phase-change materials (PCMs). These devised CNT@PCMs cleverly combine the photothermal conversion capability of CNTs and the thermal energy storage capability of traditional PCMs. Especially, the surface temperature of the prepared CNT@PCMs can be raised to 100 °C within 165 s under the solar simulator (150 mW cm–2), showing a surprising heating rate that is much higher than that of the reported works and achieving a higher photothermal conversion efficiency for solar energy in this work. Furthermore, these CNT@PCMs can hold high melting latent heat with a maximum value at 110.0 J g–1, exhibiting remarkable thermal storage ability aside from preeminent photothermal conversion capability. Intriguingly, the introduction of dynamic oxime group–carbamate bonds into the molecular structure can endow CNT@PCMs with an outstanding self-healing performance and recyclability. The broken CNT@PCMs sample can be healed in 2 min under IR-laser irradiation. Importantly, the phase-change and mechanical properties and photothermal conversion efficiency of CNT@PCMs can also remain virtually unchanged after multiple recycles. It is of great significance to design this style of CNT@PCMs for achieving the efficient utilization of solar energy and environmental protection.

Particle morphology has been regarded as an important factor affecting shear behaviors of sands, and covers three important aspects, i.e. global form (overall shape), local roundness (large-scale smoothness), and surface texture (roughness) in terms of different observation scales. Shape features of different aspects can be independent of each other but might have coupled effects on the bulk behavior of sands, which has been not explored thoroughly yet. This paper presents a systematic investigation of the coupled effects of the particle overall regularity (OR) and sliding friction on the shear behavior of dense sands using three-dimensional (3D) discrete element method (DEM). The representative volume elements consisting of ideal spheres and irregular clumps of different mass proportions are prepared to conduct drained triaxial compression simulations. A well-defined shape descriptor named OR is adopted to quantify particle shape differences of numerical samples at both form and roundness aspects, and the particle sliding friction coefficient varies from 0.001 to 1 to consider the surface roughness effect equivalently in DEM. The stress-strain relationships as well as peak and critical friction angles of these assemblies are examined systematically. Moreover, contact network and anisotropic fabric characteristics within different granular assemblies are analyzed to explore the microscopic origins of the multi-scale shape-dependent shear strength. This study helps to improve the current understanding with respect to the influence of the particle shape on the shear behavior of sands from different shape aspects.

This paper presents a novel open-source discrete element code, SudoDEM , for efficient modeling of both 2D and 3D non-spherical particles under a GPL v3 or later license. Built upon a popular open-source code YADE , our code inherits the core of a classic DEM framework empowered by OpenMP acceleration, and further offers unique features of a rich library of prime particle shapes, including poly-superellipsoids, superellipsoids, cylinders, cones, polyhedrons for 3D and disks and superellipses for 2D. Unlimited choices of more complex particle shapes can be readily generated by clumping these prime shapes. Efficient modeling of complex shaped particles hinges on contact detection. In SudoDEM , we have developed three generic and efficient contact detection algorithms, the parametric common normal (PCN) algorithm, the Gilbert–Johnson–Keerthi (GJK) algorithm, and the hybrid PCN–GJK algorithm, to handle contacts among complex-shaped particles during a typical DEM simulation. The new DEM code is validated and further showcased by multiple examples, including granular packing, triaxial compression, and landslide, its robustness, efficiency and versatility in providing realistic solutions to granular mechanics problems. The project is hosted at an open-source page at https://sudodem.github.io , while the source codes are freely available at a GitHub repository (https://github.com/SudoDEM). We foresee a great capability and potential for SudoDEM in advancing future progress in granular physics and granular mechanics and in fostering advanced simulations of critical engineering and industrial processes pertaining to granular media. Program title: SudoDEM CPC Library link to program files: https://doi.org/10.17632/brpk4g28zn.1 Developer's repository link: https://github.com/SudoDEM/SudoDEM , https://sudodem.github.io Licensing provisions: GNU General Public License 3 Programming language: C++, Python Nature of problem: Grain shape underpins important aspects of the physical and mechanical behaviors of granular media. The inability of realistic and robust modeling of particle shape has been a major obstacle for discrete-based numerical methods in solving practical problems of granular materials. Solution method: SudoDEM implements three generic algorithms of contact detection among non-spherical particles in Discrete Element Method, which provides a rich library of particle shapes available for DEM modeling of granular media. [ABSTRACT FROM AUTHOR]

Recently, the integration of electronic elements with cellular scaffolds has brought forth the ability to monitor and control tissue function actively by using flexible free-standing two-dimensional (2D) systems. Capabilities for electrically probing complex, physicochemical and biological three-dimensional (3D) microenvironments demand, however, 3D electronic scaffolds with well-controlled geometries and functional-component distributions. This work presents the development of flexible 3D electronic scaffolds with precisely defined dimensions and microelectrode configurations formed using a process that relies on geometric transformation of 2D precursors by compressive buckling. It demonstrates a capability to fabricate these constructs in diverse 3D architectures and/or electrode distributions aimed at achieving an enhanced level of control and regulation of tissue function relatively to that of other approaches. In addition, this work presents the integration of these 3D electronic scaffolds within engineered 3D cardiac tissues, for monitoring of tissue function, controlling tissue contraction through electrical stimulation, and initiating on-demand, local release of drugs, each through well-defined volumetric spaces. These ideas provide opportunities in fields ranging from in vitrodrug development to in vivotissue repair and many others.