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Low-melting-point alloys have the advantages of good biocompatibility, plasticity, and near-bone mechanical strength, making them suitable as bone defect-filling materials for direct injection into defective bone sites. However, using low-melting-point alloys for orthopedic implants poses the challenge of causing thermal damage to the surrounding bone tissue during injection. In this study, a thermosensitive hydrogel is prepared and synergistically injected into the bone defect site with BiInSn. BiInSn solidifies and releases heat during injection, while the thermosensitive hydrogel absorbs heat and transforms into a gel state, encapsulating BiInSn. Therefore, the surrounding bone tissue is effectively protected from thermal damage. When BiInSn and the thermosensitive hydrogel were injected synergistically, in vitro thermal experiments revealed that the maximum temperature of the surrounding bone tissue reached 42°C. This temperature is below the 47°C threshold, which causes permanent damage to bone tissues. In vivo experiments demonstrated that rats in the BiInSn-thermosensitive hydrogel group exhibited better recovery at the bone defect sites. These results suggest that the synergistic injection of Bi-based alloy and thermosensitive hydrogel is beneficial in reducing thermal damage to bone tissue, guiding bone tissue growth, and effectively facilitating the repair of bone defects. [ABSTRACT FROM AUTHOR]

Discrete memristor can be introduced for chaos producing conveniently even combined with easy amplitude control. Such a case is designed in this work, in which all the rest parameters are independent amplitude controllers except the only one for bifurcation. The memristor-related parameters only rescale the sequence partially or totally without revising the Lyapunov exponents. More controllers bring greater convenience for chaos application, meanwhile, less bifurcation parameters pose less risks for chaos-based engineering. The STM32-based circuit is constructed to verify the characteristics of amplitude control. Furthermore, a secure optical communication system is built based on the memristive map showing its high performance in engineering applications. [ABSTRACT FROM AUTHOR]

Earthworms have entirely soft bodies mainly composed of circular and longitudinal muscle bundles but can handle the complexity of unstructured environments with exceptional multifunctionality. Soft robots are naturally appropriate for mimicking soft animal structures thanks to their inherent compliance. Here, we explore the new possibility of using this compliance to coordinate the actuation movements of single-type soft actuators for not only high adaptability but the simultaneous multifunctionality of soft robots. A cross-linked actuator coordination mechanism is proposed and explained with a novel conceptual design of a cross-linked network, characterization of modular coordinated kinematics, and a modular control strategy for multiple functions. We model and analyze the motion patterns for these functions, including grabbing, manipulation, and locomotion. This further enables the combination of simultaneous multi-functions with this very simple actuator network structure. In this way, a soft modular robot is developed with demonstrations of a novel continuous-transportation mode, for which multiple objects could be simultaneously transported in unstructured environments with either mobile manipulation or pick-and-place operation. A comprehensive workflow is presented to elaborate the cross-linked actuator coordination concept, analytical modeling, modular control strategy, experimental validation, and multi-functional applications. Our understanding of actuator coordination inspires new soft robotic designs for wider robotic applications. [ABSTRACT FROM AUTHOR]

Conclusion: Experimental results show that the CrowdDesigner outperforms several strong personalized product description generation methods in personal interest coverage, language organization and detailed product information. In addition, the personalized product descriptions generated from the Crowd-Designer can be used as product recommendation texts on the E-commerce web pages, product recommendation pages in mobile apps, offline electronic advertising screens and so on. [ABSTRACT FROM AUTHOR]

By introducing an absolute value function for polarity balance, a unique hyperchaotic map with complete control and conditional symmetry is designed. Firstly, coexisting conditional symmetric bifurcations and hyperchaotic phase trajectories are found in the map. Then, two independent parameters are proven to provide a direct knob for partial and total amplitude control. Finally, a STM32-based hardware experiment is carried out to verify the theoretical finding. [ABSTRACT FROM AUTHOR]

Recently, the image segmentation algorithm based on neural network has made great progress in the field of medical image segmentation, but it still faces many challenges such as the small set of training sample data, the lackness of background training data, weak network generalization ability, and poor network performance. To overcome the above difficulties, a new memristive Radial Basis Function (RBF) neural network is proposed for training effectively small sample set, which shows strong power of global searching and great generalization ability. Based on the memristive neural network and K-means clustering algorithm, a new algorithm for unsupervised image segmentation is designed. Through the analysis of experimental data, it is found that the algorithm proposed in this paper can segment medical images accurately without expert labeling data. [ABSTRACT FROM AUTHOR]

The dolomite explosion in the terminal Ediacaran period has great geological significance for understanding the paleoenvironmental evolution of the Precambrian-Cambrian transition. However, dolomite origins remain controversial. Abundant dolomites in the Ediacaran Dengying Formation in the northern Yangtze Block provide a window for solving the problem. In this paper, the genesis of dolomites and the paleoenvironment of the terminal Ediacaran were studied by facies, trace elements (including rare earth elements, REEs), and carbon, oxygen, and strontium isotopes of the Dengying Formation in the Xichuan area of South Qinling, Northern Yangtze Block. The results indicate that the Dengying Formation was deposited on a carbonate platform, and four types of dolomite (i.e., micro-crystalline dolomite, fine-medium crystalline dolomite, brecciated dolomite, and saddle dolomite) are identified. According to the differences in the ∑REEs, δ13C, Z value and 87Sr/86Sr values in different types of dolomite, it is concluded that micro-crystalline dolomite mainly formed in the early diagenetic stage, fine-medium crystalline dolomite in the middle diagenetic stage, and saddle dolomite in the late diagenetic stage, while brecciated dolomite formed in the epigenetic stage. Moreover, it is determined that the dolomitization models for the Dengying Formation include the seepage-reflux, mixed water, burial, and hydrothermal dolomitization models. In addition, micro-crystalline dolomite has a Sr/Ba value far greater than 1, the Z value is usually greater than 125, δEu is positive, V/(V + Ni) is less than 0.74, and δ13C is positive, indicating that the Dengying Formation dolomite was deposited in a shallow water environment with high salinity, weak oxidation, and dry and warm climate. By comparing the characteristics of dolomite in other parts of the world in the same period, it indicates that the global climate warmed up, the ocean appeared oxygenation process, and extensive retrogression events occurred in the Precambrian-Cambrian boundary. [ABSTRACT FROM AUTHOR]

The dissolution of collagen in ionic liquids (ILs) was highly dependent on the polarity of ILs, which was influenced by their sorts and concentrations. Herein, the solubility and dispersion degree of collagen in two sorts of ILs, namely 1-ethyl-methylimidazolium tetrafluoroborate ([EMIM][BF4]) with low polarity and 1-ethyl-3-methylimidazolium acetate ([EMIM][Ac]) with high polarity in a concentration range from 10% to 70% at 10 °C were investigated. When 150 mg of collagen was added to 30 mg of ILs, the minimum soluble collagen concentration was 0.02 mg/mL in 70% [EMIM][BF4] with lowest polarity and the maximum was 3.57 mg/mL in 70% [EMIM][Ac] with highest polarity, which indicates that soluble collagen and insoluble collagen fibers were both present. For insoluble collagens, differential scanning calorimetry showed that the thermal-stability was weakened when increasing the ILs concentration and polarity, and the fiber arrangement was looser with a more uniform lyophilized structure, observed by atomic force microscopy and scanning electron microscopy. For soluble collagens, electrophoresis patterns and Fourier transform infrared spectroscopy showed that no polypeptide chain degradation occurred during dissolution, but the thermal denaturation temperature decreased by 0.26 °C~ 7.63 °C with the increase of ILs concentrations, measured by ultra-sensitive differential scanning calorimetry. Moreover, the aggregation of collagen molecules was reduced when ILs polarity was increased as determined by fluorescence measurements and dynamic light scattering, which resulted in an increased loose fiber arrangement observed by atomic force microscopy. If the structural integrity of collagen needs to be retained, then the ILs sorts and concentrations should be considered. [ABSTRACT FROM AUTHOR]

A robust framework for change detection in high-resolution (HR) images which takes into account feature importance of morphological attribute profiles (APs) is proposed. Although APs allow the discriminative extraction of geometrical features, the selection of optimal filtering thresholds is always a challenging task. In order to address this problem, the importances of multi-attribute APs, which are generated by ranges of thresholds, are calculated in advance. The APs with higher importances are chosen as input features for change detectors. Furthermore, owing to the possible incomplete feature importance model caused by randomness and small size of selected training samples through random forest, an ensemble method is conducted by integrating different results to enhance the stability of the final output. Experimental results obtained by two pairs of bi-temporal HR images demonstrate the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

The two-dimensional (2D) layered material MoS2 has attracted numerous attentions for electronics and optoelectronics applications. In this work, a novel type of MoS2-doped sol-gel glass composite material is prepared. The nonlinear optical properties of prepared MoS2/SiO2 composite material are measured with modulation depth (ΔT) of 3.5% and saturable intensity (Isat) of 20.15 MW/cm2. The optical damage threshold is 3.46 J/cm2. Using the MoS2/SiO2 composite material as saturable absorber (SA), a passive mode-locked Er-doped fiber (EDF) laser is realized. Stable conventional soliton mode-locking pulses are successfully generated with a pulse width of 780 fs at the pump power of 90 mW. In the pump power range of 100-600 mW, another stable mode-locking operation is obtained. The pulse width is 1.21 ps and the maximum output power is 5.11 mW. The results indicate that MoS2/SiO2 composite materials could offer a new way for optical applications. [ABSTRACT FROM AUTHOR]