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Improving the biomineralization of the ZrO2 ceramics surface is of great significance for field of dentistry. A femtosecond laser is used to prepare micro–nano structures on the surface of the ZrO2 ceramics. The contact angle, micromorphology, and chemical composition of the material surface are characterized using a contact angle measurement instrument, scanning electron microscope, and energy‐dispersive spectroscopy. The changes of surface wettability of different samples areanalyzed, and the biomineralization of different micropit surfaces is evaluated through hydroxyapatite (HA) deposition experiments. The results show that the deposition effect of the femtosecond laser‐textured surface is better than that of the original surface. Femtosecond laser processing improves the surface of the material, providing additional nucleation sites for HA, which is conducive to its growth and improvement of deposition efficiency. HA deposited on hydrophobic surfaces consists of a small amount of rod‐shaped and spherical particles. While the deposition effect on hydrophilic surfaces is significantly improved, the deposited particles on hydrophilic surfaces are rod‐shaped and stacked into spherical shapes, growing into pieces after combining, and the particle number increases, the density increases, and they completely cover the textured surface. This study provides a theoretical reference and experimental basis for improving its biomineralization. [ABSTRACT FROM AUTHOR]

In sports, advance sensing technologies generate massive amount of unstructured telemedicine data that need to be refined for accurate diagnosis of underlying diseases. For accurate prediction of diseases and classification of athletes' data, deep learning algorithms are frequently used at the cloud. However, the transmission of raw data of athletes to the cloud faces numerous challenges. Among them, security and privacy are a major challenge in view of the sensitive and personal information present within the unstructured data. In this paper, first we present a data block scrambling algorithm (without key management) for secured transmission and storage of ECG (electrocardiogram) data of table tennis players at the cloud. A small piece of original data stored at the cloud is used for scrambling the massive amount of remaining ECG data. The secured telemedicine data is then imported into Hadoop Distributed File System for data management, which is read by Spark framework to form Resilient Distributed Datasets. Finally, a deep learning approach is used that extracts useful features, learns the related information, and weights and sums the feature vectors at different layers for classification. Theoretical analysis proves that our proposed approach is highly robust and resilient to brute force attacks and at the same time has a much better accuracy, sensitivity, and specificity as compared to the existing approaches. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to process the wettability surface of the ZrO2 ceramics to improve their surface friction performance. Design/methodology/approach: Microtexture was processed on the surface of ZrO2 ceramics using a femtosecond laser. The three-dimensional texture morphology, surface contact angle, friction curve and wear morphology were measured by the laser confocal microscope, the contact angle meter, the reciprocating friction and wear tester and the scanning electron microscope, respectively. Based on Wenzel and partial impalement models, a geometric model of micro pits is established to study the influence mechanism of micro pit depth, diameter and distribution density on wettability and to analyze the relationship between surface wettability and tribological properties. Findings: The results show that changing the geometric characteristics of the texture will lead to a change in the solid-liquid contact mode, and then lead to a change of in the surface contact angle. Wettability is an essential factor that affects the reduction of surface friction. The construction of a reasonable texture can enhance the surface hydrophilicity, which is conducive to the formation of a lubricating film on the ceramic surface, thereby reducing abrasive and adhesive wear, and improving the wear resistance of the ZrO2 ceramic surface. Originality/value: The results provide a theoretical reference for femtosecond laser surface texture wettability regulation and tribological performance improvement. [ABSTRACT FROM AUTHOR]