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On the impact of government employment services on the quality of re-employment of unemployed fishermen in Yangtze River --A case study in Xiantao City of Hubei Province, China
Get PDFIn the transition period of the Yangtze River fishing ban policy, the retrenched fishermen are in an inferior position in the employment market due to the lack of their own employment capital, and it has become a problem to switch to employment. Based on the study of employment quality and employment capital theory, this paper uses the PLS-SEM model to process the questionnaire data on the effect of government employment services on the quality of fishermen's re-employment based on the establishment of government employment services-quality analysis system and questionnaire design and collection. The total effect of government employment services on re-employment quality was 0.685. The indirect effect of government employment services on the quality of re-employment through the mediating variable of employment conditions was smaller than the direct effect of government employment services on the quality of employment. This research may provide a basis for solving the problems of high-quality re-employment for unemployed fishermen and sustainable livelihoods for fishermen
Study on Maximum Power Limitation of Gillnet Fishing Vessels Based on EEXI
Get PDFTo address issues such as insufficient fishing vessel data records, low energy efficiency, and high emissions, this study constructs and validates a predictive model for the maximum power limitation of fishing vessels. Using gillnet fishing vessels as a case study, the Energy Efficiency Existing Ship Index (EEXI) reference line formula for gillnet fishing vessels is fitted using the nonlinear least squares method. Sensitivity analysis reveals power's impact on fishing vessels' energy efficiency. The maximum power calculation method for fishing vessels is derived by combining the EEXI calculation formula, the reference line formula, and the power-speed relationship. Three regression prediction models—Decision Tree, Random Forest, and Gradient Boosting—are used to construct prediction models with gross tonnage, length between perpendiculars, and gross tonnage and length between perpendiculars as inputs, respectively. Results show that power significantly impacts the energy efficiency of fishing vessels. The EEXI reference line formula for gillnet fishing vessels has MAE, MSE, MAPE, RMSE, and R^2 values of 13.3518, 369.5200, 18%, 19.2229, and 0.6366, respectively. The Random Forest regression model with gross tonnage as input performs best in predicting the maximum power limitation of gillnet fishing vessels, with MAE, MSE, MAPE, RMSE, and R^2 values of 5.61423, 6152.40982, 1.90888%, 78.43730, and 0.633062393, respectively. This paper provides a reliable calculation method and prediction model for the maximum power limitation of fishing vessels, offering systematic technical support and decision-making references for limiting the maximum power of fishing vessels
Effects of different feeds and stocking densities on growth and survival rates of mud crab (<em>Scylla paramamosain</em>) at the stage from megalopa to crablet-1
Get PDFMud crabs (Scylla genus) are luxury foods in high demand internationally. The efficient techniques for mud crab hatcheries are vital for providing breeds for their aquaculture, which is rapidly growing in many countries. This study aims to investigate the effects of different feeds and stocking densities on mud crabs' growth and survival rates (Scylla paramamosain) in the stage from megalopa to crablet-1 stage. Two separate experiments were conducted indoors in the 60-liter round plastic tanks (containing 50 liters of water at a 28‰ salinity). Experiment 1 investigated four feeds: frozen Artemia biomass, pureed shrimp meat, Lansy pellet feed (48% protein), and NRD pellet feed (55% protein). Megalopae (mean weight of 5.8 mg) were stocked at a density of 10/L. In experiment 2, the megalopae (mean weight of 5.4 mg) were stocked at densities of 20, 30, and 40/L and were fed the Lansy pellet feed, which was the best one selected from experiment 1. High survival rates were obtained at all four feeds (82.2–87.5%) and three stocking densities (88.4–90.1%). The growth performances in Lansy feed and frozen Artemia biomass were better than those in pureed shrimp meat and NRD pellet feed, which was seen through higher indicators of daily weight gain (DWG) and specific growth rate in weight (SGRw) (p p > 0.05). The investigated feeds and stocking densities suit the nursing mud crab (S. paramamosain) megalopa. In contrast, the Lansy pellet feeds had a stocking density of 20/L, resulting in the highest nursing efficiency
Cloning and expression patterns of espl1 gene in loach (<em>Misgurnus anguillicaudatus</em>) during gonad development
Get PDFespl1 (extra spindle pole bodies like 1), a cysteine endopeptidase, is a mitotic key player in chromosomal segregation and centriole duplication during mitosis and meiosis. Considering the espl1 gene has not been reported in aquatic organisms, we reported the isolation and expression of the espl1 gene from loach. In this study, the full-length cDNA of espl1 was cloned for the first time in loach. In loach, the full-length cDNA of espl1 consisted of 6948 bp, the open reading frame (ORF) is 6240 bp, and the espl1 gene encodes 2139 amino acids. Moreover, the deduced amino acid sequences of espl1 in loach shared the highest identity with those of Cyprinus carpio (78.39%) and Sinocyclocheilus anshuiensis (78.27%), and the sequence homology among the various separases is confined to the C-terminal region. Furthermore, tissue-specific checking results indicated that the espl1 gene of the loach gene was highly expressed in the ovary and testis, especially in stage IV oocytes and stage IV testis by Real-time quantitative PCR (qPCR). Then, whole-mount in situ hybridization analyses revealed the expression of espl1 in the early development of loach. We found that the positive signal of espl1 was observed in the notochord during the early embryo development of loach. Last but not least, when treated with luteinizing hormone-releasing hormone analog (LHRH-A2), the mRNA expression of espl1 was significantly increased in the testes and ovaries. These observations suggest that the espl1 gene had a distinct and important role in the gonads of Loach. This study will be of value for further studies into the function of the espl1 gene in fish
Legislative files: Other legislation: "Laws that Treat Hawaii Differently": Financial: Department of Commerce
Get PDFLegislative files: Other legislation: "Laws that Treat Hawaii Differently": State responses to survey (1 of 2)
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Effects of Thermal Shock from Coastal Nuclear Power Plant Discharges on the Survival of Four Fish Species Under Variable Temperature Rise
Get PDFIn this study, we simulated water temperature changes under variable frequency temperature rise conditions caused by coastal nuclear power plant discharges and conducted thermal shock tests on four fish species: Trachinotus ovatus, Nibea albiflora, Larimichthys crocea, and Acanthopagrus schlegelii at acclimated water temperatures of 25.0°C and 27.5°C during the summer. The effects of these temperature variations on the thermal shock response of the four fish species were analyzed. The results indicated that at 25.0°C, the mortality rate of N. albiflora exhibited an overall upward trend with increasing temperature and duration frequency, with an average mortality rate ranging from 10±3.3% to 38.9±3.3%. For L. crocea, mortality was observed only in the 8.5ºC-100% duration probability group, while other groups had a 0% mortality rate. At 27.5°C, A. schlegelii showed an average mortality rate of 10±3.3% at an 8.5ºC-100% duration probability, with all other groups showing 100% survival. The average mortality rate of T. ovatus at 8.5ºC-100% was 6.7±3.3%, with no mortality in the other treatment groups. The expression level of the hsp70 gene in the liver of N. albiflora increased with higher temperature rise amplitudes and longer frequency conversion durations. Similarly, the hsp70 gene expression in L. crocea and A. schlegelii increased with rising temperatures, though there were no significant differences among groups with varying frequency conversion times. In contrast, the hsp70 gene expression in T. ovatus remained relatively stable across temperature rise treatments, showing no significant differences with varying frequency conversion durations. The heat stress tolerance ranking among the four fish species was determined to be L. crocea \> N. albiflora \> T. ovatus \> A. schlegelii