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ZrC/ZrSi composite fibers were directly electro-synthesized from inexpensive and abundantly available ZrSiO4/C precursors in molten CaCl2–NaCl at 850 °C. Electrolysis was conducted at a constant voltage of 2.8 V using a graphite anode and a cathode composed of ZrSiO4/carbon mixture. The reaction mechanism of electro-synthesis process was systematically investigated by examination of partially and fully reduced samples. Results show that as-synthesized nanofiber is composed of ZrSi single crystal core and ZrC outer coating. The mechanism of composite fiber formation is a complex reaction pathway involving decomposition, electro-deoxidation and in situ carbonization. The electrochemical route in molten salt is a new promising method for simple fabrication of Zr-based composite fibers.

Black rockfish (Sebastes schlegelii) is a viviparous teleost fish whose spermatozoa were transferred into the female ovary cavity and stored for up to five months and then fertilized with the matured eggs. There is no clarity about the molecular characteristics of ovarian follicles during female sperm storage in Sebastes schlegelii. In this study, histological observation, transcriptomic analysis and hormone level detection were performed in ovaries at stages of pre-mating (PRM), post-mating (POM) and pre-fertilization (PRF). Histological observation displayed that oocytes developed from the primary growth (PG) stage to the mature stage during the three stages. Furthermore, somatic cells around the oocyte were proliferated and spermatozoa were found near the layer of epithelial cells. Transcriptomic analysis showed that there were 437 and 747 differentially expressed genes (DEGs) in ovarian comparison of PRM-vs-POM and POM-vs-PRF, respectively. GO enrichment and KEGG analysis revealed that lots of DEGs from PRM-vs-POM were linked to immune-related pathways, such as antigen processing and presentation, immune response, and complement and coagulation cascade. Meanwhile, seven DEGs associated with immune response were differentially expressed after spermatozoa treatment in ovarian tissue in vitro. While the DEGs from POM-vs-PRF were mostly enriched in the pathways related to homeostasis maintenance and cellular junction and metabolism. In addition, we found increased estrogen (E2) and 11-ketotestosterone (11-KT) level and decreased testosterone level in ovarian follicles during the sperm storage period by ELISA, suggesting that sex hormones are involved in the dynamic change of ovarian follicles. In total, this study could provide new hints for understanding the immune adaption and developmental signatures of ovarian follicles post copulation in black rockfish and other viviparous fish.

This paper proposes a novel consensus-based distributed unscented Kalman filtering algorithm with event-triggered communication mechanisms. With such an algorithm, each sensor node transmits the newest measurement to the corresponding remote estimator selectively on the basis of its own event-triggering condition. Compared to the existing approaches, the proposed algorithm can significantly reduce unnecessary data transmissions and hence save communication energy consumption and alleviate the communication burden. A sufficient condition is provided to guarantee the stochastic stability of the distributed nonlinear filtering scheme. The proposed algorithm is applicable to a wide range of distributed estimation tasks, e.g., tracking a moving target with multiple unmanned aerial vehicles (UAVs). Simulation results demonstrate the feasibility and effectiveness of the proposed filtering algorithm.

In this paper, the particle filtering problem is studied for a class of general nonlinear cyber-physical systems with non-Gaussian noises under Round-Robin protocol (RRP) subject to the randomly occurring deception attacks. In order to prevent the data from collisions and alleviate the communication overhead for the shared network with limited resources, the RRP is introduced in the sensor-to-filter channel to schedule the multiple sensors with a predefined transmission order. Under the RRP, only one sensor can be granted the access to the shared channel for measurement transmission at each time instant. A Bernoulli-distributed stochastic variable is utilized to describe the characteristic of random occurrence of deception attacks initiated by the adversaries. A RRP-based particle filtering algorithm is developed by establishing a modified likelihood function, where the statistical property of the randomly occurring deception attacks is exploited and the RRP-induced effect on the filter design is reflected. Finally, an illustrative example regarding the target tracking problem is provided to verify the feasibility and effectiveness of the developed particle filtering scheme.