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The well-being of marine ecosystems significantly influences biodiversity and ecological equilibrium amidst pressing challenges such as overfishing, water pollution, and climate change. Drawing upon data from two fishery stock surveys conducted in the inshore waters of Hainan Island in 2022, this study undertook a comprehensive evaluation of the marine ecosystem’s health status in the region. Employing the Fish Index of Biological Integrity (F-IBI) analysis method, coupled with an examination of the structural and functional aspects of the fish community, our research sheds light on the prevailing conditions. Our study revealed a spatial dichotomy within the fish communities of the study area and delineated them into two distinct groups: the northwestern and southeastern ones, with evident disparities in community structure between the two. By employing indicator screening and calculation, we segmented the fish health index in the inshore waters of Hainan Island into five tiers. Despite discernible anthropogenic influences, the ecological health of these waters remained generally robust. Notably, the mean F-IBI of fall (56.30) significantly exceeded that of spring (48.16) (P < 0.01). Furthermore, regarding spatial distribution, the ecological well-being of the southeastern waters surpassed that of the northwestern and Qionghzhou Strait waters. This study represents a pioneer endeavor to apply ecological health assessment methodologies towards informing resource management and conservation strategies for the inshore fisheries of Hainan Island. By furnishing a scientific foundation, our research contributes to the pursuit of sustainable marine ecological development within this locale.

Based on fishery resources and environmental data collected during six cruises conducted in the spring and autumn from 2021 to 2023 in the northern Beibu Gulf, South China Sea, we conducted an analysis on spatiotemporal distribution of crimson seabream (Paerargyrops edita). We employed a gradient forest analysis (GFA) and generalized additive model (GAM) to investigate the relationship between their distribution and six environmental factors, including sea surface temperature (SST), sea surface salinity (SSS), sea surface chlorophyll a concentration (Chla), bathymetry (Depth), sea surface height (SSH), as well as the Niño 3.4 index (NI). The results revealed distinct spatiotemporal variations in the distribution of crimson seabream in the northern Beibu Gulf, with an average stock density of 114.21 kg/km2. During spring, there was a significantly higher abundance at 160.46 kg/km2 compared to the autumn value of 67.95 kg/km2. In the first analysis, based on 1000 runs of the GFA, it was observed that the selected explanatory variables demonstrated excellent predictive capabilities for variations in stock density. Specifically, the SST, SSS, and NI were found to have a high importance, indicating a significant influence of climate and environmental factors such as the El Niño-Southern Oscillation (ENSO) and SST on the crimson seabream abundance. Subsequently, we constructed a GAM to further investigate the impact of environmental factors on the distribution patterns of crimson seabream. The GAM also confirmed a strong correlation between the selected environmental factors and crimson seabream abundance. The main distribution of crimson seabream abundance exhibited a significant negative correlation with the SST, which fell within the range of 24–28 °C. The stock density of crimson seabream slightly increased at SSS levels ranging from 32.5 PSU to 33.5 PSU, indicating a correlation between the two factors. The crimson seabream was distributed across a Chla range of 0–4 mg/m3, with a gradual increase in stock density as the Chla levels increased. Stock density was positively correlated with SSH, but was negatively correlated with NI. In this study, we examined the distribution of crimson seabream and its main influencing factors by incorporating various environmental factors and a network analysis under different climate events. This research provides theoretical support for investigating the mechanisms of fishery stock in response to climate change. It also contributes to the existing body of knowledge on changes in fish resources in Beibu Gulf during abnormal climate events.

To solve the problem of difficulty in predicting the impact point clearly and promptly during projectile flight, this paper proposes an improved ballistic-impact-point prediction method. A certain type of high-spinning tailed projectile is taken as the research object for online real-time landing point prediction research. This study comprehensively utilizes the real-time radar measurement data and the geomagnetic data measured by the bomb-carried geomagnetic sensor. It applies the four-degree-of-freedom ballistic model to predict the landing point. First, the roll angular velocity is calculated based on the geomagnetic data, after which the radar real-time measurement data are segmentally fitted using the improved crayfish algorithm. Then, the fitted parameters are substituted into the four-degree-of-freedom ballistic model. Finally, the C-K method is used to identify the aerodynamic parameters, and the identified aerodynamic parameters are used for fallout prediction. The simulation results show a small deviation between the predicted and actual impact points using the improved ballistic-impact-point prediction method.

Background and objective: Pelvic bone tumors represent a harmful orthopedic condition, encompassing both benign and malignant forms. Addressing the issue of limited accuracy in current machine learning algorithms for bone tumor image segmentation, we have developed an enhanced bone tumor image segmentation algorithm. This algorithm is built upon an improved full convolutional neural network, incorporating both the fully convolutional neural network (FCNN-4s) and a conditional random field (CRF) to achieve more precise segmentation. Methodology: The enhanced fully convolutional neural network (FCNN-4s) was employed to conduct initial segmentation on preprocessed images. Following each convolutional layer, batch normalization layers were introduced to expedite network training convergence and enhance the accuracy of the trained model. Subsequently, a fully connected conditional random field (CRF) was integrated to fine-tune the segmentation results, refining the boundaries of pelvic bone tumors and achieving high-quality segmentation. Results: The experimental outcomes demonstrate a significant enhancement in segmentation accuracy and stability when compared to the conventional convolutional neural network bone tumor image segmentation algorithm. The algorithm achieves an average Dice coefficient of 93.31 %, indicating superior performance in real-time operations. Conclusion: In contrast to the conventional convolutional neural network segmentation algorithm, the algorithm presented in this paper boasts a more intricate structure, proficiently addressing issues of over-segmentation and under-segmentation in pelvic bone tumor segmentation. This segmentation model exhibits superior real-time performance, robust stability, and is capable of achieving heightened segmentation accuracy.

Aimed at addressing the strong nonlinearity and strong external disturbances that cause flight control issues in conventional guided projectiles, as well as the slow response and structural vibrations that often occur in sliding mode control systems, which have a detrimental impact on the control effect and ultimate hit precision, a new type of fast and robust control algorithm with a unidirectional mode has been designed. The objective is to design an optimized aerodynamic shape for the projectile and to establish a dynamic model of the roll channel and a motion model of the entire trajectory. The dynamics of a new global terminal sliding mode are proposed, and an adaptive parameter term is realized by calculating the state of the critical sliding mode surface, which ensures that the tracking error converges within a finite time. Its combination with an adaptive approaching law is used to further speed up convergence while damping the structural vibration of the system. The bias error of the roll angle is constructed as the controller and simulation calculations are conducted on the basis of the aforementioned framework. The stability and time convergence of the control system are demonstrated through Lyapunov theory. The results indicate that, in comparison to the conventional terminal sliding mode controller, the designed controller exhibits a markedly rapid convergence rate and stronger robustness in tracking the command signal. Moreover, it also maintains a stable motion attitude of the projectile throughout the entire process. The superior control effect under different guidance schemes and the strong external disturbances also further reflect the anti-jamming capability and tracking performance of the system.

As an economic species widely distributed in the South China Sea (SCS), the purpleback flying squid (Sthenoteuthis oualaniensis) still has a large potential for exploitation, and the variations in its use as a resource are highly correlated with environmental and other factors. In this study, using a generalized additive model (GAM) and gradient forest analysis (GFA), in conjunction with environmental factors, the distribution of purpleback flying squid surrounding the Xisha and Zhongsha islands during the fishing moratorium period was investigated. The results indicated that catch per unit effort (CPUE) had a gradual increase from May to July 2023 in the primary fishing area surrounded the Xisha Islands during May to June, then moved southward towards 13–15° N after July. CPUE is used as an important indicator to reflect the abundance of the fishery, while the GFA results show that CPUE has a better fit than catch in this study. Therefore, the subsequent analysis focused on CPUE. Longitude and sea surface temperature (SST) were of relative higher importance, followed by sea surface salinity (SSS), latitude, chlorophyll a concentration (Chla), sea surface height (SSH), and mixed layer depth (MLD). Longitude and CPUE had a significant, positive correlation. The CPUE gradually increased with latitude within 14–16° N. The CPUE increased slowly as SST increased from 29.5 to 30.5 °C in the primary fishing area. The Chla in this fishing zone was 0–0.2 mg/m3 and displayed a significant positive association with CPUE. Conversely, SSS, SSH, and MLD had negative correlations with CPUE. These findings will promote the sustainable utilization of purpleback flying squid in the SCS.

The Indonesian greeneye spurdog (or a dogfish shark), Squalus montalbani Whitley, 1931, is widely distributed in the warm temperate to tropical waters of Indonesia, Philippines, the island of Taiwan, and Australia. Previous studies suggested that the distribution of dogfish shark species in the South China Sea is composed of two species, Squalus mitsukurii Jordan et Snyder, 1903 and Squalus brevirostris Tanaka, 1917. In March 2020 a dogfish shark specimen was collected from the Nansha (Spratly) Islands, South China Sea. We identified it as S. montalbani based on morphology and mitochondrial DNA barcoding. Our results confirmed the presence of S. montalbani in the South China Sea, leading us to conclude that it represents a new species record of the genus Squalus in the region. Furthermore, our findings demonstrate that the combined approach is highly effective in identifying Squalus species that share similar morphological characteristics.

Background and objective: Bone tumor is a kind of harmful orthopedic disease, there are benign and malignant points. Aiming at the problem that the accuracy of the existing machine learning algorithm for bone tumor image segmentation is not high, a bone tumor image segmentation algorithm based on improved full convolutional neural network which consists fully convolutional neural network (FCNN-4s) and conditional random field (CRF). Methodology: The improved fully convolutional neural network (FCNN-4s) was used to perform coarse segmentation on preprocessed images. Batch normalization layers were added after each convolutional layer to accelerate the convergence speed of network training and improve the accuracy of the trained model. Then, a fully connected conditional random field (CRF) was fused to refine the bone tumor boundary in the coarse segmentation results, achieving the fine segmentation effect. Results: The experimental results show that compared with the traditional convolutional neural network bone tumor image segmentation algorithm, the algorithm has a great improvement in segmentation accuracy and stability, the average Dice can reach 91.56%, the real-time performance is better. Conclusion: Compared with the traditional convolutional neural network segmentation algorithm, the algorithm in this paper has a more refined structure, which can effectively solve the problem of over-segmentation and under-segmentation of bone tumors. The segmentation prediction has better real-time performance, strong stability, and can achieve higher segmentation accuracy.

The ocellated angelshark (Squatina tergocellatoides Chen, 1963) is a threatened shark within the family Squatinidae. In the present study, we reported the mitochondrial genome sequence of the ocellated angelshark. The complete mitochondrial genome is 16,683 bp in length and contains 37 mitochondrial genes and a control region as similar to most fishes. In addition, we constructed a maximum-likelihood phylogenetic tree of S. tergocellatoides and its relative species. This work will provide molecular data for further studies on S. tergocellatoides.

Abstract Background Macrophages are one of the important cells in immune system. In this article, we aim to explore the regulatory role of miR-455-3p on proliferation and osteoblast differentiation of RAW264.7 cells. Methods Expression levels of genes and proteins in cells were tested via qRT-PCR and western blot. The targeted correlation between miR-455-3p and PTEN was identified by luciferase analysis. MTT assay and flow cytometry were applied to detect the proliferation and apoptosis of cells. Osteoclastogenesis was completed by stimulating RAW 264.7 cells with RANKL. Tartrate-resistant acid phosphatase (TRAP) activity in different groups of cells were assessed. Results Firstly, we determined that up-regulation of miR-455-3p promoted the proliferation and inhibited apoptosis of RAW 264.7 cells. MiR-455-3p deficiency played opposite effect in RAW 264.7 cells. Additionally, osteoclastogenesis-related factors (TRAP, CTSK and NFATc1) expression levels were remarkably up-regulated in miR-455-3p-mimic group of RAW264.7 cells treated with RANKL, but decreased in inhibitor group. Luciferase assay proved that miR-455-3p targeted PTEN. We took a further step and found overexpression of PTEN significantly inhibited the increased proliferation and osteoblast differentiation of RAW264.7 cells induced by miR-455-3p. Conclusions Our findings supported basic to explore the molecular mechanism of proliferation and osteoblast differentiation of RAW264.7 cells.

The objectives of this study were to evaluate the effect of stock enhancement on Penaeus japonicus (Bate, 1888) in Beibu Gulf, South China Sea, and to investigate whether stock enhancement has genetically affected the natural population of P. japonicus in the Beibu Gulf waters. Five microsatellite loci were used to identify released individuals among recaptured specimens. In total, 13 of the 487 recaptured individuals were found with their corresponding parents for this release of shrimp seedlings, accounting for 2.67% of the total recaptured P. japonicus. Furthermore, it was determined that the genetic differences among the broodstock, released, and recaptured populations of P. japonicus were small and did not cause significant changes in the genetic structure of P. japonicus in the area. In conclusion, the stock enhancement of P. japonicus in Beibu Gulf had a certain effect on resource restoration, and there is no difference in the genetic characteristics obtained by the microsatellite markers compared to the original population in this area.

This study explored the ecological niche and interspecific relationships among the main fish species in the coastal waters of Hainan Island based on data from fishery stock surveys conducted in the spring and autumn of 2022. The methods of chi-square test, percentage of co-occurrence (PC), association coefficient (AC), cluster analysis, and redundancy analysis were used to analyze the interspecific associations and influence of environmental factors on the ecological niches of fish communities. According to the cluster analysis of niche breadth, 20 main fishes could be divided into broad, medium, and narrow niche species. There were four and eight broad niche species in spring and autumn, respectively. The ranges of niche overlap values were 0.001–0.91 in spring and 0–0.87 in autumn, indicating that the species differed and were similar in their ability to utilize resources, survive in habitats, and prey. According to the variance ratio and statistic value W, the main fishes in spring showed a significant positive association, whereas those in autumn showed a positive association, but not at a significant level, indicating that the main fishes in spring were more closely associated with each other. There were 56 species pairs in the 2 seasons that were significantly associated (χ2 ≥ 3.841). AC and PC tests revealed that the interspecific association was strong and tended to be positive. According to the redundancy analysis, environmental factors such as surface temperature, water depth, and pH significantly affected the main fishes in spring, while environmental factors such as dissolved oxygen, bottom temperature, surface salinity, and pH significantly affected those in autumn.

Chub mackerel (Scomber japonicus) is widely distributed in the northwestern Pacific Ocean and is utilized by China, Korea, and Japan in different seasons and areas. Generally, chub mackerel is divided into Tsushima Warm Current (TWC) and Pacific stocks based on its different distribution, migration, and life-history traits. The two stocks showed obvious interannual to decadal variability in abundance with evident different variation patterns. Chub mackerel has extensive spawning areas in the northwestern Pacific Ocean, with the main spawning period from March to June, and the suitable spawning SST (sea surface temperature) ranging from 15°C to 22°C. To explore the temperature effects on different variations of the two stocks, we estimated the average temperature suitability index (TSI) for chub mackerel in main spawning areas during the spawning period from March to June based on the relationship between the probability of spawning and the specific SST. Results showed that the TSIs in the shelf waters of China seas and the waters of the Tsushima Strait displayed simultaneous abrupt changes in the late 1990s for the TWC stock, whereas the TSI in the Pacific coast of Japan had a regime shift in the late 1970s for the Pacific stock. The spatio-temporal variation in spawning temperature suitability may have had an important impact on the recovery of the Pacific stock after the 2000s. We also found that there is a non-stationary relationship between chub mackerel abundance and TSI, which is driven by climate variabilities such as the Siberian High and the Aleutian Low. Moreover, TWC stock showed non-stationary relationship with TSI, and the threshold years was identified in the 1990s, and the non-stationary relationship between TSI and Pacific stock, with thresholds occurring in the late 1970s. Our research provides a reasonable explanation for the variations in the two stocks and their responses to TSI variability and offers an improved understanding of the climate-induced non-stationary relationships between chub mackerel abundance and physical drivers.

Sexual growth dimorphism is a common phenomenon in teleost fish and has led to many reproductive strategies. Growth- and sex-related gene research in teleost fish would broaden our understanding of the process. In this study, transcriptome sequencing of shortfin scad Decapterus macrosoma was performed for the first time, and a high-quality reference transcriptome was constructed. After identification and assembly, a total of 58,475 nonredundant unigenes were obtained with an N50 length of 2,266 bp, and 28,174 unigenes were successfully annotated with multiple public databases. BUSCO analysis determined a level of 92.9% completeness for the assembled transcriptome. Gene expression analysis revealed 2,345 differentially expressed genes (DEGs) in the female and male D. macrosoma, 1,150 of which were female-biased DEGs, and 1,195 unigenes were male-biased DEGs. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses showed that the DEGs were mainly involved in biological processes including protein synthesis, growth, rhythmic processes, immune defense, and vitellogenesis. Then, we identified many growth- and sex-related genes, including Igf, Fabps, EF-hand family genes, Zp3, Zp4 and Vg. In addition, a total of 19,573 simple sequence repeats (SSRs) were screened and identified from the transcriptome sequences. The results of this study can provide valuable information on growth- and sex-related genes and facilitate further exploration of the molecular mechanism of sexual growth dimorphism.

The nearshore ecosystem of Hainan Island plays a crucial role as a breeding habitat for a wide variety of economically valuable fish species. Gaining insight into the structure of the fish community and the environmental factors that may impact them is highly significant in this marine region. This study collected fish data from 50 sampling sites using bottom trawling surveys. Methods including the swept area method, ecological indices, and abundance/biomass curve (ABC) analysis were employed to assess fish resource density and diversity. A comprehensive identification revealed a total of 363 fish species, encompassing 24 orders, 114 families, and 226 genera, with Perciformes being the dominant group. Spring exhibited higher fish abundance and biomass compared with autumn, with the southwestern waters as the primary concentration area. Acropoma japonicum, Decapterus maruadsi, and Navodon xanthopterus were dominant in spring, while Leiognathus bindus, Saurida tumbil, and Champsodon atridorsalis were dominant in autumn, indicating a seasonal shift towards smaller and lower-value fish species. A variability exceeding 80% was observed through SIMPER analysis, and a disrupted community structure was evident in the eastern and southern waters. Temperature and salinity were identified as primary environmental factors influencing the fish community. Overall, this study provides valuable insights into the nearshore fish community of Hainan Island, aiding in the understanding of its structure and dynamics.

The complete mitochondrial genome of the Cephalopholis urodeta (Serranidae: Epinephelinae) was sequenced by next-generation sequencing method on the basis of one female specimen collected from coral reef areas at the Mischief Reef, South China Sea. The mitogenome is 16,593 bp in length, including 13 protein-coding genes, 22 tRNA genes, two rRNA genes and a D-loop region. The overall content of A + T is 55.66%, which is significantly higher than the C + G content (44.34%). Among four bases, C shows the lowest frequency (15.99%). Phylogenetic tree based on the 13 protein-coding genes was constructed for analyzing the position of C. urodeta. The results provide useful insights into further studies on population genetics and phylogenetics of groupers.

Fishery resource and environmental data from four surveys conducted in the Hainan Island offshore area from March 2021 to June 2022 were used to investigate the spatiotemporal distribution of round scad (Decapterus maruadsi). A generalized additive model was applied to explore the relationships among abundance and distribution, also biotic and abiotic factors (i.e., temperature, salinity, chlorophyll-a concentration, water depth, phytoplankton abundance, zooplankton abundance, and jack mackerel (Trachurus japonicas) abundance). Round scad abundance (average 67.17 kg/km2) showed distinct spatial and seasonal differences around Hainan Island, with highest abundance in summer (171.72 kg/km2) and lowest abundance in spring (3.06 kg/km2). The optimal model revealed that jack mackerel abundance, sea bottom temperature, sea surface temperature, and latitude very significantly (p < 0.01) affected round scad distribution. Jack mackerel abundance (mainly in the range 0–50 kg/km2) was positively correlated with round scad distribution. The distribution showed a dome-shaped relationship with bottom water temperature in the range 18–30 °C, with maximum abundance at 24 °C. The distribution was negatively correlated with surface water temperature in the range 22–30 °C. Sea surface chlorophyll-a concentration and longitude were significantly correlated (p < 0.05) with round scad distribution. The results provide theoretical support to further investigate the formation mechanism of round scad fishing grounds and to enrich knowledge of pelagic fish abundance in the continental-shelf waters of the northern South China Sea.

Among the anthropogenic stresses that marine ecosystems face, biological invasions are one of the major threats. Recently, as a result of increasingly intense anthropogenic disturbance, numerous marine species have been introduced to their non-native ranges. However, many introduced species have uncertain original sources. This prevents the design and establishment of methods for controlling or preventing these introduced species. In the present study, genomic sequencing and population genetic analysis were performed to detect the geographic origin of the introduced Pinctada fucata population in the Mischief Reef of the South China Sea. The results of population genetic structure analysis showed a close relationship between the Mischief Reef introduced population and the Lingshui population, indicating that Lingshui may be the potential geographical origin. Furthermore, lower heterozygosity and nucleotide diversity were observed in the introduced population in Mischief Reef, indicating lower genetic diversity than in other native populations. We also identified some selected genomic regions and genes of the introduced population, including genes related to temperature and salinity tolerance. These genes may play important roles in the adaptation of the introduced population. Our study will improve our understanding of the invasion history of the P. fucata population. Furthermore, the results of the present study will also facilitate further control and prevention of invasion in Mischief Reef, South China Sea.

Among vertebrates, teleost fishes exhibit the largest array of sex-determining systems, resulting in many reproductive strategies. Screening these fish for sex-related genes could enhance our understanding of sexual differentiation. The lizardfish, Saurida elongata (Temminck & Schlegel, 1846), is a commercially important marine fish in tropical and subtropical seas of the northwest Pacific. However, little genomic information on S. elongata is available. In this study, the transcriptomes of three female and three male S. elongata were sequenced. A total of 49.19 million raw read pairs were generated. After identification and assembly, a total of 59,902 nonredundant unigenes were obtained with an N50 length of 2070 bp. Then, 38,016 unigenes (63.47% of the total) were successfully annotated through multiple public databases. A comparison of the unigenes of different sexes of S. elongata revealed that 22,507 unigenes (10,419 up-regulated in a female and 12,088 up-regulated in a male) were differentially expressed between sexes. Then, numerous candidate sex-related genes were identified, including dmrt2, dmrt4, foxl2, zps and starts. Furthermore, 23,941 simple sequence repeats (SSRs) were detected in SSR-containing sequences. This informative transcriptome analysis provides valuable data to increase the genomic resources of S. elongata.

Accumulating evidence has supported that osteosarcoma is heterogeneous, and several subtypes have been identified based on genomic profiling. Immunotherapy is revolutionizing cancer treatment and is a promising therapeutic strategy. In contrast, few studies have identified osteosarcoma classification based on immune biosignatures, which offer the optimal stratification of individuals befitting immunotherapy. Here, we classified osteosarcoma into two clusters: immunity high and immunity low using the single-sample gene-set enrichment analysis and unsupervised hierarchical clustering. Immunity_H subtype was associated with high immune cells infiltration, a favorable prognosis, benefit to immunotherapy, high human leukocyte antigen gene expression, and activated immune signal pathway indicating an immune-hot phenotype. On the contrary, the Immunity_L subtype was correlated with low immune cell infiltration, poor prognosis, and cancer-related pathway, indicating an immune-cold phenotype. We also identified TYROBP as a key immunoregulatory gene associated with CD8+ T cell infiltration by multiplex immunohistochemistry. Finally, we established an immune-related prognostic model that predicted the survival time of osteosarcoma. In conclusion, we established a new classification system of osteosarcoma based on immune signatures and identified TYROBP as a key immunoregulatory gene. This stratification had significant clinical outcomes for estimating prognosis, as well as the immunotherapy of osteosarcoma patients.

In the present study, the complete mitogenome of Cephaloscyllium fasciatum has been sequenced and assembled. The complete mitochondrial genome is 16,509 bp in length and contains 37 mitochondrial genes and a control region as other fishes. The nucleotide composition of C. fasciatum mitogenome showed an anti-G bias and an excess of AT content. Furthermore, maximum-likelihood phylogenetic tree was constructed based on 13 protein-coding genes of C. fasciatum and other 15 sharks. This work will provide molecular data for studies on phylogeny and evolution in the family Scyliorhinidae.

Multivariate time series forecasting recently has received extensive attention with its wide application in finance, transportation, environment, and so on. However, few of the currently developed models have considered the impact of noise on prediction. Since multivariate time series contains multiple subsequences with strong nonlinear fluctuations, it is also difficult to obtain satisfactory prediction results. In this paper, aiming at improving prediction performance, we have proposed a novel ensemble three-phase model called adaptive noise reducer-stacked auto-encoder-validating-AdaBoost-based long short-term memory (ANR-SAE-VALSTM). We start with an introduction of a novel ANR for time series noise elimination. The SAEs are then used to extract features from the de-noised multivariate time series. Finally, we feed the de-noised features into the VALSTM to train an ensemble over-fitting prevention predictor. The proposed model is employed on the Beijing PM2.5 dataset and GEFCom2014 Electricity Price dataset. Compared with other popular models, the proposed model has achieved the best prediction performance in all prediction horizons. In addition, a careful ablation study is conducted to demonstrate the efficiency of our model design.

Sexual growth dimorphism is a common phenomenon in teleost fish. However, the mechanism of this complex phenomenon remains unclear. The fine-patterned puffer (Takifugu poecilonotus; Temminck and Schlegel, 1850) exhibits female-biased sexual size dimorphism similar to other pufferfish. In this study, the transcriptomes of female and male T.poecilonotus were sequenced, 285.95 million raw read pairs were generated from sequence libraries. After identification and assembly, a total of 149,814 nonredundant unigenes were obtained with an N50 length of 3538 bp. Of these candidates, 122,719 unigenes (81.91% of the total) were successfully annotated with multiple public databases. The comparison analysis revealed 10,385 unigenes (2034 in females and 8351 in males) were differentially expressed between different sexes of T.poecilonotus. Then, we identified many candidate growth- and sex-related genes, including Dmrt1, Sox3, Spatas, Prl/Prlr, fabps, Ghr, and Igf1r. In addition to these well-known genes, Fabp4 was identified for the first time in fish. Furthermore, 68,281 simple sequence repeats (SSRs) loci were screened and identified in the transcriptome sequence of T.poecilonotus. The results of our study could provide valuable information on growth- and sex-associated genes and facilitate further exploration of the molecular mechanism of sexual growth dimorphism.

In this paper, a new dual-spin guided projectile that is equipped with ten lateral impulse jets is proposed for trajectory correction. To guide the overall design of the projectile and the control system, a linear motion model of the projectile that was subjected to a lateral impulse was obtained based on a full nonlinear seven-degree-of-freedom (7-DOF) dynamic model. The trajectory correction process of a lateral impulse was divided into two stages. To explain the principle of lateral impulse trajectory correction, the analytical solutions of the linear model of these two stages were obtained. Analytical and numerical solutions were compared to verify the accuracy of the linear model. It is concluded that the analytical and numerical solutions are in good agreement.

A complex wind field refers to the typical atmospheric disturbance phenomena existing in nature that have a great influence on the flight of aircrafts. Aimed at the issues involving large volume of data, complex computations and a single model in the current wind field simulation approaches for flight environments, based on the essential principles of fluid mechanics, in this paper, wind field models for two kinds of wind shear such as micro-downburst and low-level jet plus three-dimensional atmospheric turbulence are established. The validity of the models is verified by comparing the simulation results from existing wind field models and the measured data. Based on the principle of vector superposition, three wind field models are combined in the ground coordinate system, and a comprehensive model of complex wind fields is established with spatial location as the input and wind velocity as the output. The model is applied to the simulated flight of a rocket projectile, and the change in the rocket projectile’s flight attitude and flight trajectory under different wind fields is analyzed. The results indicate that the comprehensive model established herein can reasonably and efficiently reflect the influence of various complex wind field environments on the flight process of aircrafts, and that the model is simple, extensible, and convenient to use.

This paper addresses the difficult problem of measuring the attitude of a high-spinning projectile and presents a novel method for estimating the pitch and yaw angles of the projectile in flight. The method is based on analysis of the external moment of the rotating projectile during flight and theoretical derivations obtained from the dynamics’ equations. First, the principle of zero-crossing method is introduced, which explains the process of geomagnetic azimuth and roll measurements by the non-orthogonal geomagnetic sensor combination. Then, the dynamics constraint equations between the Euler angles and flight-path angle, trajectory deflection angle of the projectile are derived using the dynamics equations of the projectile rotating around the centroid, and analysis of the flight characteristics of the projectile in stable flight. Next, the spatial orientation relationship between pitch, yaw angles and magnetic azimuth is established based on the physical principle of geomagnetic azimuth. Finally, the pitch and yaw angles are estimated using the unscented Kalman filter (UKF), with the dynamics constraint equations serving as the driving equations. In the UKF prediction stage, the Runge-Kutta method is used to discretize the state equation that improves the prediction accuracy. Simulation results show that the proposed method can be used to accurately calculate the pitch and yaw angles, and results of experimental data processing also verify the feasibility of the proposed method for real-world applications.

The implementation of IP technology in wireless sensor networks has promoted the development of many smart scenarios. To enhance secure access in IP-enabled wireless sensor networks, access control to sensor nodes is a necessary process. However, access control currently faces two challenges, feasibility and preservation of user access privacy. In this paper, we propose eHAPAC, a novel privacy-preserving access control model for IP-enabled wireless sensor networks. The contributions of our paper include three parts. First, this paper integrates the Hidra access control protocol and APAC privacy-preserving model, addressing the issue of privacy-preserving access control in resource-constrained devices. Second, this paper proposes an enhanced Hidra protocol to implement the unlinkability of protocol message exchanges. Third, to solve the problem of third party credibility, this paper improves the group signature-based APAC model and utilizes blockchain technology to manage the storage and publication of public group signature keys. Security analysis and performance evaluation prove that our protocol is secure and effective.

As an emerging and promising computing paradigm in the Internet of things (IoT),edge computing can significantly reduce energy consumption and enhance computation capabilityfor resource-constrained IoT devices. Computation offloading has recently received considerableattention in edge computing. Many existing studies have investigated the computation offloadingproblem with independent computing tasks. However, due to the inter-task dependency in variousdevices that commonly happens in IoT systems, achieving energy-efficient computation offloadingdecisions remains a challengeable problem. In this paper, a cloud-assisted edge computing frameworkwith a three-tier network in an IoT environment is introduced. In this framework, we first formulatedan energy consumption minimization problem as a mixed integer programming problem consideringtwo constraints, the task-dependency requirement and the completion time deadline of the IoT service.To address this problem, we then proposed an Energy-efficient Collaborative Task ComputationOffloading (ECTCO) algorithm based on a semidefinite relaxation and stochastic mapping approachto obtain strategies of tasks computation offloading for IoT sensors. Simulation results demonstratedthat the cloud-assisted edge computing framework was feasible and the proposed ECTCO algorithmcould effectively reduce the energy cost of IoT sensors.

In previous studies, our research team successfully transferred the Ns genome from Psathyrostachys huashanica Keng into Triticum aestivum (common wheat cv. 7182) using embryo culture. In the present study, one of these lines, i.e., hybrid progeny 25-10-3, which matured about 10-14 days earlier than its wheat parent, was assessed using sequenced characterized amplified region (SCAR) analysis, EST-SSR and EST-STS molecular markers, and genomic in situ hybridization (GISH). We found that this was a stable wheat-P. huashanica disomic addition line (2n = 44 = 22 II) and the results demonstrated that it was a 6Ns disomic chromosome addition line, but it exhibited many different features compared with previously characterized lines, i.e., a longer awn, early maturation, and no twin spikelets. It was considered to be an early-maturing variety based on the early stage of inflorescence initiation in field experiments and binocular microscope observations over three consecutive years. This characteristic was distinct, especially from the single ridge stage and double ridge stage until the glume stage. In addition, it had a higher photosynthesis rate and economic values than common wheat cv. 7182, i.e., more spikelets per spike, more florets per spikelet, more kernels per spike, and a higher thousand-grain weight. These results suggest that this material may comprise a genetic pool of beneficial genes or chromosome segments, which are suitable for introgression to improve the quality of common wheat.

The aim of this study was to characterize a Triticum aestivum-Psathyrostachys huashanica Keng (2n = 2x = 14, NsNs) disomic addition line 2-1-6-3. Individual line 2-1-6-3 plants were analyzed using cytological, genomic in situ hybridization (GISH), EST-SSR, and EST-STS techniques. The alien addition line 2-1-6-3 was shown to have two P. huashanica chromosomes, with a meiotic configuration of 2n = 44 = 22 II. We tested 55 EST-SSR and 336 EST-STS primer pairs that mapped onto seven different wheat chromosomes using DNA from parents and the P. huashanica addition line. One EST-SSR and nine EST-STS primer pairs indicated that the additional chromosome of P. huashanica belonged to homoeologous group 7, the diagnostic fragments of five EST-STS markers (BE404955, BE591127, BE637663, BF482781 and CD452422) were cloned, sequenced and compared. The results showed that the amplified polymorphic bands of P. huashanica and disomic addition line 2-1-6-3 shared 100% sequence identity, which was designated as the 7Ns disomic addition line. Disomic addition line 2-1-6-3 was evaluated to test the leaf rust resistance of adult stages in the field. We found that one pair of the 7Ns genome chromosomes carried new leaf rust resistance gene(s). Moreover, wheat line 2-1-6-3 had a superior numbers of florets and grains per spike, which were associated with the introgression of the paired P. huashanica chromosomes. These high levels of disease resistance and stable, excellent agronomic traits suggest that this line could be utilized as a novel donor in wheat breeding programs.

Mobile sinks can achieve load-balancing and energy-consumption balancing across the wireless sensor networks (WSNs). However, the frequent change of the paths between source nodes and the sinks caused by sink mobility introduces significant overhead in terms of energy and packet delays. To enhance network performance of WSNs with mobile sinks (MWSNs), we present an efficient routing strategy, which is formulated as an optimization problem and employs the particle swarm optimization algorithm (PSO) to build the optimal routing paths. However, the conventional PSO is insufficient to solve discrete routing optimization problems. Therefore, a novel greedy discrete particle swarm optimization with memory (GMDPSO) is put forward to address this problem. In the GMDPSO, particle’s position and velocity of traditional PSO are redefined under discrete MWSNs scenario. Particle updating rule is also reconsidered based on the subnetwork topology of MWSNs. Besides, by improving the greedy forwarding routing, a greedy search strategy is designed to drive particles to find a better position quickly. Furthermore, searching history is memorized to accelerate convergence. Simulation results demonstrate that our new protocol significantly improves the robustness and adapts to rapid topological changes with multiple mobile sinks, while efficiently reducing the communication overhead and the energy consumption.

Based on bottom trawl survey data collected in November 2009 (autumn), February 2010 (winter), May 2010 (spring), and August 2010 (summer), the seasonal variation in the trophic structure of the fish community in Dongshan Bay and adjacent waters was investigated. A total of 114 species of fish were caught in surveys throughout the year. According to their feeding habits, the fish species in the surveyed area were classified into six functional groups, including planktivores (FG1), planktivores/benthivores (FG2), benthivores (FG3), benthivores/piscivores (FG4), piscivores (FG5), and omnivores (FG6). FG3 was the most diverse group, with 43 species, followed by FG4, with 29 species. The biomass of FG3 was the highest among all functional groups throughout the year and in each individual season. FG1 and FG5 had higher biomass proportions in spring than in the other seasons, accounting for 8.02% and 16.72%, respectively. The functional group diversity (HFD) and species diversity (Hs) showed similar variations, reaching their lowest values in winter and highest values in summer. In 2009-2010, the mean trophic position of the fish community in Dongshan Bay and adjacent waters was 3.64. This value was 3.74 in winter (highest), 3.49 in summer (lowest), 3.71 in spring, and 3.63 in autumn. The relationship between the trophic position and the mean body mass indicated that the seasonal variation in the mean body mass of high-trophic-level fish species was the highest in winter, followed by autumn, spring, and summer. In general, with seasonal and temporal changes, large-bodied, high-trophic-level fishes were gradually replaced by small-bodied, low-trophic-level fishes in the fish community of Dongshan Bay and adjacent waters in 2009-2010, and the trophic structure tended to become simplified. [ABSTRACT FROM AUTHOR]