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A polyamino acid with zincophilic chains is introduced as a multifunctional electrolyte additive for uniform Zn deposition and inhibition of side reactions.

A seaweed-like porous carbon anode, prepared using fish scale as the precursor and K2SO4 as the auxiliary, achieves high capacities and superior stability for KIC.

In this brief, the state estimation problem is investigated for a class of randomly delayed artificial neural networks (ANNs) subject to probabilistic saturation constraints (PSCs) and non-Gaussian noises under the redundant communication channels. A series of mutually independent Bernoulli distributed white sequences are introduced to govern the random occurrence of the time delays, the saturation constraints, and the transmission channel failures. A comprehensive redundant-channel-based communication mechanism is constructed to attenuate the phenomenon of packet dropouts so as to enhance the quality of data transmission. To compensate for the influence of randomly occurring time delays, the corresponding occurrence probability is exploited in the process of particle generation. In addition, an explicit expression of the likelihood function is established based on the statistical information to account for the impact of PSCs and redundant channels. By virtue of the modified operations of particle propagation and weight update, a particle-filter-based state estimation algorithm is proposed with mild restriction on the system type. Finally, an illustrative example with Monte Carlo simulations is provided to demonstrate the effectiveness of the developed state estimation scheme.

Growth is the most valuable economic trait for improving aquaculture fish species, since fast growth can reduce labor cost and make more economic benefits. However, the knowledge about how many and which genes are related to the growth of Chinese tongue sole is limited. High-throughput sequencing screening of variants is a fast, economical and accurate assay to identify genes related to growth in crops, livestock and other aquaculture products. In the present study, genome-wide resequencing of 30 female Chinese tongue sole individuals from large and small groups to screen growth trait-related variations (SNPs, InDels) was carried out. In total, 6545735 SNPs and 1016745 InDels were detected, while 31 genes related to growth traits were identified. Their functions were mainly involved in muscle architecture, post-embryonic development, neurosensory development and hormone regulation. Furthermore, 18 of the 31 genes related to growth trait are located on W chromosome, indicating that W chromosome plays an important role in regulating the body size of female tongue soles. The markers and genes identified in our study can be applied to selective breeding of tongue sole and thus will promote the aquaculture industry and increase economic efficiency.

The quantitative real-time reverse transcription PCR (qRT-PCR) is a widely used technique to analyze gene expression levels. Selecting a suitable reference gene is a crucial step to obtain an accurate result in qRT-PCR. However, most previous studies on fishes adopted reference genes that were commonly used in mammals without validation. In this study, we utilized 89 transcriptome datasets covering early developmental stages and different adult tissues, and carried out transcriptome-wide identification and validation of reference genes in Sebastes schlegelii. Finally, 121 candidate reference genes were identified based on four criteria. Eight candidates (METAP2, BTF3L4, EIF5A1, TCTP, UBC, PAIRB, RAB10, and DLD) and four commonly used reference genes in mammals (TUBA, ACTB, GAPDH, RPL17) were selected for validation via qRT-PCR and four statistical analysis methods (delta-Ct, Best-Keeper, geNorm, and NormFinder). The results indicated that when the black rockfish are cultured in a general condition, the eight candidate reference genes are more stable than traditional reference genes in mammals, and RAB10, EIF5A1, PAIRB and BTF3L4 are the best reference genes in rockfish. This is the first study to conduct transcriptome-wide identification and validation of reference genes for quantitative RT-PCR in the black rockfish, and lay an important foundation for gene expression analysis in teleost.

In this paper, the particle filtering problem is investigated for a class of nonlinear/non-Gaussian systems with energy harvesting sensors subject to randomly occurring sensor saturations (ROSSs). The random occurrences of the sensor saturations are characterized by a series of Bernoulli distributed stochastic variables with known probability distributions. The energy harvesting sensor transmits its measurement output to the remote filter only when the current energy level is sufficient, where the transmission probability of the measurement is recursively calculated by using the probability distribution of the sensor energy level. The effects of the ROSSs and the possible measurement losses induced by insufficient energies are fully considered in the design of filtering scheme, and an explicit expression of the likelihood function is derived. Finally, the numerical simulation examples (including a benchmark example for nonlinear filtering and the applications in moving target tracking problem) are provided to demonstrate the feasibility and effectiveness of the proposed particle filtering algorithm.

This paper investigates the particle filtering problem for a class of nonlinear/non-Gaussian systems under the dynamic event-triggered protocol. In order to avert frequent data transmission and reduce the communication overhead, a dynamic event-triggered transmission mechanism is adopted to decide whether the data should be transmitted or not. We first consider a scenario where all sensor nodes selectively transmit their newly obtained measurements to a central node, and a full likelihood function at the central node is derived by fusing the transmitted measurements and the information embodied in the non-triggered measurements. Based on the derived full likelihood function, a centralized auxiliary particle filtering algorithm is proposed to select those particles that are more likely to match the current measurement information. Next, based on the diffusion strategy, a distributed auxiliary particle filtering algorithm is further developed, where the local measurements and the local posteriors (approximated by the Gaussian mixture models) are exchanged among neighboring nodes under the dynamic event-triggered communication strategy. Finally, the effectiveness of the proposed filtering schemes is demonstrated via Monte Carlo simulations in a target tracking problem with received-signal-strength sensors.

The Collagen Type VII Alpha 1 Chain (COL7A1) is associated with a variety of cancers, however, COL7A1 gene expression in human lung squamous cell carcinoma (LUSC) and its prognostic value have not been well studied. In this study, we used bioinformatics database to analyze the relationship between COL7A1 expression and survival in LUSC patients such as Oncomine, GEPIA, UALCAN, and STRING. And we used Kaplan–Meier plotter to analyze the prognosis of high or low expression of COL7A1 in different patients. We found that COL7A1 was significantly overexpressed in patients with LUSC. Additionally, in the survival analysis, COL7A1 expression was significantly associated with worse overall survival (OS), first progression (FP), Post-progression survival (PPS) in LUSC patients. Moreover, COL7A1 is closely associated with known biomarkers and key factors of LUSC. We used functional annotation enrichment analysis to show that genes co-expressed with COL7A1 were enriched in biological process (BP), cellular component (CC), molecular function (MF) and KEGG pathways. Furthermore, Laminin 332 and its association with COL7A1 may lead to the activation of the PI3K signaling pathway, ultimately leading to squamous cell carcinoma (SCC). This has also been mentioned in other people's research. Therefore, our work was designed to demonstrate the potential of COL7A1 as a prognostic biomarker in LUSC.

In the present study, the PLC characteristic parameters and DSA mechanism of Al-(2.86~9.41) Mg alloy sheets were investigated during tensile testing at room temperature with a tensile rate of 1 × 10−3 s−1. On the basis of the solution Mg concentrations in the α-Al matrix, the initial vacancy concentration, the second-phase particle configuration and the recrystallized grain configuration are almost the same by quenching treatment. The results show that the type of room-temperature tensile stress–strain curves of quenched Al-(2.86~9.41) Mg alloy sheets varied according to the Mg content. The type of stress–strain curve of the Al-2.86 Mg alloy sheet was B + C, while the type of stress–strain curve of the Al-(4.23~9.41) Mg alloy sheets was C. When the quenched Al-(2.86~9.41) Mg alloy sheets were stretched at room temperature, the strain cycle of the rectangular waves corresponding to the high stress flow ΔεTmax and stress drop amplitude Δσ on the zigzag stress–strain curve of alloy sheets increased with increasing the Mg content. Moreover, the strain cycle of ΔεTmax and Δσ on the stress–strain curve of alloy sheets increased gradually with increasing tensile deformation. The yield stress of quenched Al-(2.86~9.41) Mg alloy sheets increased gradually with increasing the Mg content. Moreover, the critical strain corresponding to yield stress εσ and the critical strain corresponding to the occurrence of the PLC shearing band εc of alloy sheets both increased with increasing the Mg content. However, the difference in flow strain value Δεc−σ between εc and εσ of alloy sheets decreased gradually with increasing the Mg content.

Tumor necrosis factor receptor-associated factors (TRAFs) are signaling mediators for Toll-like receptor (TLR) and tumor necrosis factor (TNFR) superfamily that play important roles in organism immune response. However, reports on systematic identification of TRAF gene family in teleost fish and the function of TRAFs in innate immunity of black rockfish (Sebastes schlegelii) are lacked. In our study, eight TRAF genes were identified and characterized, namely, SsTRAF2a, SsTRAF2a-like, SsTRAF2b, SsTRAF3, SsTRAF4, SsTRAF5, SsTRAF6 and SsTRAF7 in S. schegelii. Furthermore, we analyzed their sequences, conserved domains, gene structures, motif compositions, phylogeny, tissue expression patterns in healthy and Vibro. anguillarum challenged individuals. All the SsTRAFs contained typical conserved domain, including C-terminal MATH domain and N-terminal RING finger domain. Analyses of gene structures and motifs showed the distribution of exon-intron and conserved motifs in S. schegelii and serval other teleost fish. We also analyzed the expression file of SsTRAFs in five immune-relate organs, liver, spleen, kidney, gill and intestine in healthy and bacterial challenged fish. The results indicated that all SsTRAF member were widely involved in immune response after pathogenic bacteria infection. In summary, the analyses of TRAFs in S. schegelii will be helpful to better understand the diverse roles of TRAF genes in the innate immune response to bacterial challenge.

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.

Fibroblast growth factors (FGFs) are short polypeptides that play essential roles in various cellular biological processes, including cell migration, proliferation, and differentiation, as well as tissue regeneration, immune response, and organogenesis. However, studies focusing on the characterization and function of FGF genes in teleost fishes are still limited. In this study, we identified and characterized expression patterns of 24 FGF genes in various tissues of embryonic and adult specimens of the black rockfish (Sebates schlegelii). Nine FGF genes were found to play essential roles in myoblast differentiation, as well as muscle development and recovery in juvelines of S. schlegelii. Moreover, sex-biased expression pattern of multiple FGF genes was recorded in the species’ gonads during its development. Among them, expression of the FGF1 gene was recorded in interstitial and sertoli cells of testes, promoting germ-cell proliferation and differentiation. In sum, the obtained results enabled systematic and functional characterization of FGF genes in S. schlegelii, laying a foundation for further studies on FGF genes in other large teleost fishes.

In this paper, the event-triggered filtering problem is investigated for the nonlinear systems subject to correlated noises. The stochastic event-triggered communication strategy is adopted herein to avert the frequent information exchange and hence mitigate the network communication burden while retaining the Gaussianity of innovation process. In order to handle the correlated characteristic of the process and the measurement noises, an alternative assumption that the two-step predicted estimate satisfies Gaussian distribution is made. In the simulation, the usefulness of the developed algorithms is illustrated by two examples.

Teleost fish are the most diverse group of vertebrates and provide opportunities to study the evolution of sex determination (SD) systems. Using genomic and functional analyses, we identified a male-specific duplication of anti-Müllerian hormone (amh) gene as the male master sex-determining (MSD) gene in Sebastes schlegelii. By resequencing 10 males and 10 females, we characterized a 5 kb-long fragment in HiC_Scaffold_12 as a male-specific region, which contained an amh gene (named amhy). We then demonstrated that amhy is a duplication of autosomal amh that was later translocated to the ancestral Y chromosome. amha and amhy shared high-nucleotide identity with the most significant difference being two insertions in intron 4 of amhy. Furthermore, amhy overexpression triggered female-to-male sex reversal in S. schlegelii, displaying its fundamental role in driving testis differentiation. We developed a PCR assay which successfully identified sexes in two species of northwest Pacific rockfish related to S. schlegelii. However, the PCR assay failed to distinguish the sexes in a separate clade of northeast Pacific rockfish. Our study provides new examples of amh as the MSD in fish and sheds light on the convergent evolution of amh duplication as the driving force of sex determination in different fish taxa.

Black rockfish (Sebastes schlegelii) is a teleost species where eggs are fertilized internally and retained in the maternal reproductive system, where they undergo development until live birth (termed viviparity). In the present study, we report a chromosome-level black rockfish genome assembly. High-throughput transcriptome analysis (RNA-seq and ATAC-seq), coupled with in situ hybridization (ISH) and immunofluorescence, identify several candidate genes for maternal preparation, sperm storage and release, and hatching. We propose that zona pellucida (ZP) genes retain sperm at the oocyte envelope, while genes in two distinct astacin metalloproteinase subfamilies serve to release sperm from the ZP and free the embryo from chorion at pre-hatching stage. Finally, we present a model of black rockfish reproduction, and propose that the rockfish ovarian wall has a similar function to uterus of mammals. Taken together, these genomic data reveal unprecedented insights into the evolution of an unusual teleost life history strategy, and provide a sound foundation for studying viviparity in non-mammalian vertebrates and an invaluable resource for rockfish ecology and evolution research.

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.

Myosins are important eukaryotic motor proteins that bind actin and utilize the energy of ATP hydrolysis to perform a broad range of functions such as muscle contraction, cell migration, cytokinesis, and intracellular trafficking. However, the characterization and function of myosin is poorly studied in teleost fish. In this study, we identified 60 myosin family genes in a marine teleost, black rockfish (Sebastes schlegelii), and further characterized their expression patterns. myosin showed divergent expression patterns in adult tissues, indicating they are involved in different types and compositions of muscle fibers. Among 12 subfamilies, S. schlegelii myo2 subfamily was significantly expanded, which was driven by tandem duplication events. The up-regulation of five representative genes of myo2 in the skeletal muscle during fast-growth stages of juvenile and adult S. schlegelii revealed their active role in skeletal muscle fiber synthesis. Moreover, the expression regulation of myosin during the process of myoblast differentiation in vitro suggested that they contribute to skeletal muscle growth by involvement of both myoblast proliferation and differentiation. Taken together, our work characterized myosin genes systemically and demonstrated their diverse functions in a marine teleost species. This lays foundation for the further studies of muscle growth regulation and molecular mechanisms of indeterminate skeletal muscle growth of large teleost fishes.

Myosins are important eukaryotic motor proteins that bind actin and utilize the energy of ATP hydrolysis to perform a broad range of functions such as muscle contraction, cell migration, cytokinesis, and intracellular trafficking. However, the characterization and function of myosin is poorly studied in teleost fish. In this study, we identified 60 myosin family genes in a marine teleost, black rockfish (Sebastes schlegelii), and further characterized their expression patterns. myosin showed divergent expression patterns in adult tissues, indicating they are involved in different types and compositions of muscle fibers. Among 12 subfamilies, S. schlegelii myo2 subfamily was significantly expanded, which was driven by tandem duplication events. The up-regulation of five representative genes of myo2 in the skeletal muscle during fast-growth stages of juvenile and adult S. schlegelii revealed their active role in skeletal muscle fiber synthesis. Moreover, the expression regulation of myosin during the process of myoblast differentiation in vitro suggested that they contribute to skeletal muscle growth by involvement of both myoblast proliferation and differentiation. Taken together, our work characterized myosin genes systemically and demonstrated their diverse functions in a marine teleost species. This lays foundation for the further studies of muscle growth regulation and molecular mechanisms of indeterminate skeletal muscle growth of large teleost fishes.

Skeletal myoblasts are activated satellite cells capable of proliferation and differentiation. Studies on mammalian myoblast differentiation and myogenesis could be carried out in vitro thanks to the availability of mouse myoblast cell line C2C12. Lacking of muscle cell line hinders the studies of teleost fish myogenesis. Here, we established a continuous skeletal muscle cell line from juvenile rockfish (Sebastes schlegelii) muscle using explant method and subcultured more than 50 passages for over 150 days. Stable expression of myoblast-specific marker, MyoD (myoblast determination protein) and the potential of differentiation into multi-nucleated skeletal myotubes upon induction suggested the cell line were predominately composed of myoblasts. Transcriptome analysis revealed a total of 4375 genes differentially expressed at four time points after the switch to differentiation medium, which were mainly involved in proliferation and differentiation of myoblasts. KIF22 (kinesin family member 22) and POLA1 (DNA polymerase alpha 1) were identified as the key genes involved in fish myoblast proliferation whereas MYL3 (myosin light chain 3) and TNNT2 (troponin T2) were determined as the crucial genes responsible for differentiation. In all, the continuous myoblasts cultured in this study provided a cell platform for future studies on marine fish myoblast differentiation and myogenesis. The molecular process of myoblast differentiation revealed in this study will open a window into the understanding of indeterminate muscle growth of large teleost.

Additional file 2: Fig. S2. Tissue expression pattern of genes involved in regulation of vasoconstriction. Heatmap was constructed by comparing 20 tissues. The x‐axis shows sampled tissues, with the prefix F_ for female and M_ for male samples, and the y‐axis shows genes. The color scale shows standardized TPM values normalized by Z-score method. Five genes (Ssc_10023120, Ssc_1004710, Ssc_10011522, Ssc_10023117 and Ssc_10023118) have a bias expression in ovarian wall and genitalia, three of which are Bdkrb2 genes (Ssc_10023117, Ssc_10023118 and Ssc_10023120).

Additional file 5: Fig. S4. Similarity comparison of amino acid sequences of the Bdkrb2 ORF in black rock fish. Ssc_13, Ssc_10023113; Ssc_14, Ssc_10023114; Ssc_15, Ssc_10023115; Ssc_16, Ssc_10023116; Ssc_17, Ssc_10023117; Ssc_18, Ssc_10023118; Ssc_19, Ssc_10023119; Ssc_20, Ssc_10023120. The results are shaded to four levels. Dark shadows indicate very high conservative amino acid residues.