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The purpose of this study was to investigate the adaptive strategies and compensatory growth mechanisms of juvenile Epinephelus coioides under starvation stress. The fish with an initial body weight of 8.88 ± 0.06 g were starved for 0 day (F0, control), 3 days (F3), 6 days (F6), 9 days (F9), 12 days (F12), and 15 days (F15), followed by feeding periods of 30 days, 27 days, 24 days, 21 days, 18 days, and 15 days, respectively. The results are shown as follows: (1) E. coioides could achieve complete or partial compensatory growth by improving both feeding rate and feed conversion efficiency. (2) The viscerosomatic index and the hepatosomatic index of the test fish decreased linearly with the duration of starvation (P < 0.05), while the condition factor did not significantly decrease (P > 0.05). At the end of feeding, all the physical body indicators of the test fish recovered or exceeded the control levels. (3) The lipid and glycogen contents of the test fish decreased continuously throughout the entire starvation process, with noticeable protein consumption occurring in the later stages of starvation (P < 0.05). At the end of the feeding period, apart from a significant reduction in crude lipid contents in the F12 and F15 groups compared to the control group (P < 0.05), the biochemical composition of the test fish was restored or even surpassed that of the control group. (4) The activity of digestive enzymes could be stimulated by starvation, enabling the efficient utilization of energy storage substances. In conclusion, it is advisable to limit the period of starvation for juvenile E. coioides to 12 days, which means that the ratio of starvation period to feeding period should not exceed two‐thirds. [ABSTRACT FROM AUTHOR]

The rabbitfish Siganus oramin is an important naturally caught and aquaculture fish species. Intestinal microbiota can affect the metabolism and immunity of fish, which is closely related to the habitat of the host. In this study, we collected the wild fry S. oramin from a natural sea area, and cultured them in outdoor and indoor ponds, respectively, and investigated the changes in serum biochemical indexes and intestinal microbial community in three different habitats. The results showed that compared with the wild population, the serum total protein content of the outdoor culture population increased significantly. The indoor culture population had significantly higher triglyceride and total cholesterol contents than that of the outdoor culture population. Additionally, the intestinal microbial richness indexes ACE and Chao1 of the cultured population were higher than those of the wild population, especially the indoor culture, but Shannon and Simpson had no obvious changes. The relative abundances of Firmicutes, Spirochaetae and Bacteroidetes increased in the outdoor culture population, but decreased in the indoor culture population; those of Proteobacteria and Cyanobacteria were completely the opposite. Some putative beneficial bacteria (Lactobacillus, Clostridium sensu stricto 1, and Intestinibacter) and harmful bacteria (Vibrio, Photobacterium, Desulfovibrio, Streptococcus) all decreased in the intestines of the cultured population when compared with the wild population, while Akkermansia and Faecalibacterium were enriched in the outdoor culture population. These results reveal that a change in habitat environment, whether an outdoor or an indoor pond, positively influenced the intestinal microbiota of the rabbitfish, which is beneficial to the healthy culture of the fish from the perspective of microbial community. [ABSTRACT FROM AUTHOR]

The low thermal conductivity and liquid-phase leakage of phase change materials seriously hinder their large-scale applications. Porous materials have been identified as an effective way to address the leakage and provide a thermally conductive network. Therefore, we designed an expanded graphite-based multifunctional composite phase change thermal storage materials for personal thermal management and antimicrobial in medical protection. Expanded graphite (EG) was used as the matrix, silver nanowires (Ag NWs) as the functional enhancement materials, and n-octadecane (OD) as the thermal storage materials. OD and Ag NWs were adsorbed in the porous structure of EG by vacuum-assisted impregnation. Finally, EG/Ag NWs/OD were combined with non-woven fabrics (N) by one-step hot pressing method to obtain EG/Ag NWs/OD-N composite with excellent comprehensive performance. With the mass ratio of EG to Ag NWs of 13:7, EG/Ag NWs/OD-N exhibited a thermal conductivity of 2.0130 W m−1 K−1, which was improved by 1070.3% compared with pure OD. EG/Ag NWs/OD-N has a melting enthalpy of 137.85 J·g−1 and a crystallization enthalpy of 128.97 J·g−1. In addition, EG/Ag NWs/OD-N display great antibacterial properties, thermal cycling stability, shape stability, and cycling persistence and showed excellent temperature control in protective clothing applications, offering great potential for large-scale applications. [ABSTRACT FROM AUTHOR]

The adverse effect on speed ripple and vibration makes it necessary to evaluate the cogging torque. Due to the tolerance of stator and rotor stacks as well as nonuniform magnetization of permanent magnet, the amplitude of cogging torque is unequal in different rotor position. As a result, the verification of theoretical analysis becomes difficult. Therefore, the cogging torque average is used to weigh it. In view of the large least common multiple of multi slot/pole Permanent magnet motor, which means, there are multiple cogging torque cycles per rotor revolution, a cogging torque measurement method is proposed. Through simple devices such as arm, weight, digital gauge, resolver, and so on, the amplitude and period of cogging torque can be accurately measured without site restrictions. The correctness of the method is verified by simulation and experiment, and that can be used as a supplement to cogging torque evaluation for multi slot/pole PMM. [ABSTRACT FROM AUTHOR]

Antibiotic residues, such as tetracycline (TET), in aquatic environments have become a global concern. The liver and gut are important for immunity and metabolism in aquatic organisms. In this study, juvenile groupers were subjected to 1 and 100 μg/L TET for 14 days, and the physiological changes of these fish were evaluated from the perspective of gut-liver axis. After TET exposure, the liver showed histopathology, lipid accumulation, and the elevated ALT activity. An oxidative stress response was induced in the liver and the metabolic pattern was disturbed, especially pyrimidine metabolism. Further, intestinal health was also affected, including the damaged intestinal mucosa, the decreased mRNA expression levels of tight junction proteins (ZO-1 , Occludin , and Claudin-3), along with the increased gene expression levels of inflammation (IL-1β , IL-8 , TNF-α) and apoptosis (Casp-3 and p53). The diversity of intestinal microbes increased and the community composition was altered, and several beneficial bacteria (Lactobacillus , Bacteroidales S24-7 group, and Romboutsia) and harmful (Aeromonas , Flavobacterium , and Nautella) exhibited notable correlations with hepatic physiological indicators and metabolites. These results suggested that TET exposure can adversely affect the physiological homeostasis of groupers through the gut-liver axis. • The liver showed obvious histopathological changes, lipid accumulation, and oxidative stress. • Liver metabolic pattern especially pyrimidine metabolism was disturbed. • Intestinal health including tight junction, inflammation and apoptosis indexes were affected. • Intestinal microbial diversity increased and the community composition and function were varied. • Several intestinal bacteria were correlated with the physiological indexes and metabolites of the liver. [ABSTRACT FROM AUTHOR]

It is generally accepted that Astragalus polysaccharides (APS) supplementation can makes beneficial effects to fish. However, the adverse effects of APS to fish remains poorly understood. In the present study, Asian seabass Lates calcarifer were studied to assess the influence of different doses of APS on growth, health and resistance to Vibrio harveyi. Results showed that supplemental APS with 0.10 to 0.20% significantly boosted the growth performance, the protease and lipase activities of L. calcarifer. Compared with control diet, the villus length of L. calcarifer fed with APS supplemented diets was significantly higher. L. calcarifer fed with APS supplementation diets also significantly facilitated the antioxidant capacity and immune function. Meanwhile, supplemental APS with 0.10 to 0.15% significantly promoted liver health by up-regulating the expression of anti-inflammatory cytokines and down-regulating the expression of pro-inflammatory cytokines. Furthermore, survival rate of L. calcarifer challenged with V. harveyi was higher in diets supplemented with APS compared to the control. However, 0.20% APS significantly hindered the growth performance and caused immunostimulatory fatigue in L. calcarifer compared to 0.10% APS. Taken together, the present study demonstrates that supplementation APS with 0.10% is the optimal level for promoting the growth performance, health and resistance to V. harveyi of L. calcarifer , while 0.20% APS exerts adverse effects on L. calcarifer. Our findings provide novel recommendations for the application of APS supplementation in farmed fish. [Display omitted] • Both beneficial and adverse effects of Astragalus polysaccharides (APS) on Lates calcarifer were studied. • 0.10% APS is the optimal level for promoting the growth, health and resistance of L. calcarifer to V. harveyi. • 0.20% APS hindered the growth performance and caused immunostimulatory fatigue to L. calcarifer compared to 0.10% APS. [ABSTRACT FROM AUTHOR]

The effects of dietary chitosan (0, 2, 4, 6, 8 and 10 g/kg) on the growth, health condition and disease resistance of golden pompano Trachinotus ovatus were evaluated. Dietary chitosan significantly enhanced weight gain, with the highest observed in fish fed the 6 g/kg chitosan diet. This chitosan level significantly promoted gut health by increasing villus length, lipase and protease activities and intestinal barrier-related genes expression. Meanwhile, dietary 6 g/kg chitosan improved the inflammatory response and anti-oxidative capacity of fish by regulating the expression of genes involved in NF-κB pathway and Nrf2 pathway, respectively. Furthermore, after challenge with Vibrio harveyi for 2 weeks, the survival rate increased significantly when dietary chitosan level was 6 g/kg. Overall, our results indicate that 6 g/kg chitosan is the optimal dose for enhancing growth, health and disease resistance of fish, but excessive chitosan (10 g/kg) weakens its beneficial effects. [Display omitted] [ABSTRACT FROM AUTHOR]

• The KH-560 was utilized as a cross-linking agent to enhance interaction between HCNTs and PEG. • The shape-stabilized PEG-based PCMs (PPCs) have good stability and improved thermal conductivity. • The PPCs show great potential for application in thermal management and temperature regulation. To improve the thermal conductivity and shape-stability of polyethylene glycol (PEG), a series of novel PEG based phase change materials (PPCs) have been successfully synthesized by grafted polymerization, in which PEG as the phase change ingredient, hydroxylated carbon nanotubes (HCNTs) as the thermal conductive filler and γ-glycidyl ether oxypropyl trimethoxysilane (KH-560) as the bridge. The results indicate that the HCNTs does not agglomerate during phase transition since the HCNTs are introduced into the molecular structure of the PEG by KH-560. So, it can maintain good thermal conductivity and thermal stability after 100 thermal cycles. As the result, the latent heat of phase change for PPC is in the range of 119.9 ∼ 127.9 J·g−1, and the phase transformation temperature is in the field of 311.7 ∼ 330.9 K. The thermal conductivity of the PPC is 0.7081 W·m−1·K−1 as adding 9.0 wt% HCNTs, which is 2.2 times that of pure PEG. The temperature regulation experimental results reveal that PPC 5 has an obvious buffering effect in the temperature ranges of 311.7 ∼ 330.9 K during the heating and cooling process. It shows good potential for application in thermal energy storage and temperature regulation. [ABSTRACT FROM AUTHOR]

Simple Summary: This prospective study examined the impact of various factors on return to work (RTW) for head and neck cancer (HNC) survivors at 3 and 12 months after treatment. The study included 227 participants aged 65 years or younger. Within 3 months, 92 participants RTW and 30 retired. At 12 months, 80 participants were still working and another 51 participants had RTW. Hindrances to RTW at 3 months were advanced tumour stage (stage III and IV), whereas hindrances at 12 months were oral and larynx cancer. Facilitators of RTW included having a white-collar job, living in a relationship and early tumour stages. The study underscored that disease stage significantly hindered RTW, and work type and having a spouse or partner were nonclinical factors influencing RTW. These findings offer valuable insights for healthcare professionals and policymakers, which can aid in the development of strategies and support systems to enhance the RTW experience for HNC survivors. Striving to return to work is of great importance to many cancer survivors. The purpose of the study is to prospectively investigate the factors that hinder and facilitate return to work (RTW) at 3 and 12 months after the end of treatment in head and neck cancer (HNC) survivors and whether these factors influence the ability to continue working after treatment. Participants (n = 227) aged ≤ 65 years at diagnosis with HNC were included. Data were collected before the start of treatment and at 3 and 12 months after the end of treatment. The Rubin causal model was used for statistical analysis. Within the 3-month follow-up period, 92 participants had RTW and 30 had retired. At the 12-month follow-up, 80 of these participants were still working, another 51 participants had RTW, and five participants working still suffered from cancer. The hindrance to RTW within 3 months was advanced tumour stage (stage III and IV) (p = 0.0038). Hindrances to RTW at the 12-month follow-up were oral cancer (p = 0.0210) and larynx cancer (p = 0.0041), and facilitators were living in a relationship (p = 0.0445) and a white-collar job (p = 0.00267). Participants with early tumour stage (stage I and II) (p = 0.0019) and a white-collar job (p = 0.0185) had earlier RTW. The conclusion is that disease factors were the most important hindrances to RTW, and type of work and living with a spouse or partner were nonclinical factors influencing RTW. [ABSTRACT FROM AUTHOR]

Groupers culture are severely affected by infectious diseases. Nervous necrosis virus (NNV) can destroy the nervous system and causes massive deaths. Intestinal microbiota is an important biological barrier against pathogen invasion. In this study, we investigated the changes in intestinal microbial community and gene transcription of tiger grouper following NNV infection. Compared with the control group, the richness and diversity of intestinal microbial was induced by NNV infection, with the increased level of Firmicutes (especially class Bacilli and Clostridia) and decreased levels of Proteobacteria and Bacteroidetes. Several genus such as Lactobacillus , Acinetobacter , Escherichia-Shigella , Enterobacter , Flavobacterium and Stenotrophomonas were increased, while Alloprevotella , Bacteroides and Demequina were decreased. The carbohydrate metabolism of intestinal microbial was also decreased. The differentially expressed genes in head kidney were mainly associated with hemopoiesis and the development of immune system and hematopoietic or lymphoid organ. Several immune-related genes such as MHC class II antigen, CXC chemokine receptors (CXCR1 and CXCR4), heat shock proteins (HSP60, HSP70, HSP90), cytochrome C, immunoglobulin light chain and hepcidin were up-regulated, while interleukin (IL-8 nd IL-15), CXCR3 and complement (C1QL3 and C7) were down-regulated. These results revealed that NNV infection caused intestinal microbiota variation and affected the immunity of tiger grouper, which will be beneficial to utilize the characteristics of intestinal microbial to facilitate grouper healthy culture. • The richness, diversity and composition of intestinal microbiota were altered. • Several putative beneficial substance producing and pathogenic bacteria were fluctuated. • The head kidney hemopoiesis and the development of immune system and organ were altered. • Several intestinal bacteria and immune gene markers were identified. [ABSTRACT FROM AUTHOR]

Experimental diets were formulated including the suitable lipid level (10%, PC), the high‐lipid level (16%, HL), and HL containing sodium acetate diets (HS). Three diets were fed golden pompano (Trachinotus ovatus) (initial body weight: 12.88 ± 0.03 g) for 8 weeks. The results showed HL diets significantly increased hepatosomatic index (HSI) and abdominal fat percentage (ASF), aggravated liver lipid deposition, and caused blood metabolic disorder and liver damage (P < 0.05). Moreover, the fish fed HL diets significantly decreased intestinal villus number (VN) and muscular layer thickness (MLT) (P < 0.05), accompanied with an increased trend in the relative abundance of intestinal pathogenic bacteria such as Mycoplasma and Photobacterium. However, the fish fed HS diets significantly decreased the HSI and AFP, relieved hepatic lipid deposition, improved blood and liver metabolism, and intestinal morphology in comparison to the fish fed HL diets (P < 0.05). More importantly, sodium acetate addition improved intestinal microbiota by inhibiting the proportion of pathogens (Mycoplasma and Vibrio) and increasing the abundance of probiotics (Bacteroidales_S24-7_group_norank, Cetobacterium, Bacteroides, and Lachnospiraceae_NK4A136_group). Furthermore, there was a strong correlation between these bacteria (Mycoplasma, Vibrio, Lachnospiraceae_NK4A136_group, Bacteroidales_S24-7_group_norank, Bacteroides, and Cetobacterium) and main physiological indices. In conclusion, sodium acetate improved blood performance, alleviated hepatic lipid deposition induced by HL diets, and boosted the growth and intestinal health for golden pompano. [ABSTRACT FROM AUTHOR]

Although β-glucan has diverse benefits for fish health, the potential adverse impacts of excessive supplementation are poorly understood. This study investigated the optimal dosage of β-glucan for coral trout and explored the adverse effects of excessive supplementation. The results revealed that moderate β-glucan supplementation (1) significantly enhanced the weight gain rate and specific growth rate (SGR); (2) significantly improved the intestinal villus length (0.10%), muscle thickness (0.05–0.15%), and α-amylase and chymotrypsin activities (0.05–0.15%); (3) significantly increased liver catalase (CAT), glutathione reductase (GR), alkaline phosphatase, complement 3, immunoglobulin M (IgM), lysozyme, serum superoxide dismutase, CAT, glutathione peroxidase, GR, total antioxidant capacity, acid phosphatase, complement 4, and IgM activities and significantly reduced malondialdehyde contents; (4) upregulated genes in the liver associated with copper-zinc superoxide dismutase (SOD-1), manganese superoxide dismutase (SOD-2), CAT, GSH-Px1a, ACP6, AKP, LZ-c, IgM, C3, and C4-b. However, 0.20% β-glucan significantly inhibited the growth performance of coral trout compared with 0.10% β-glucan. Thus, 0.10% β-glucan represents the optimal dosage for promoting growth, antioxidant activity, and immune responses in coral trout, while higher β-glucan levels weakened these beneficial effects. With an SGR established by a cubic regression analysis, the optimal level of β-glucan for maximal growth of coral trout is 0.082%. This study provides new insights into the health impacts of β-glucan on fish. [ABSTRACT FROM AUTHOR]

Simple Summary: Siganus oramin, as a commercial species, is a well-received table fish in southeastern China. However, valuable reproduction-related data are still scarce. In the present study, gonad transcriptome analysis was first performed using Illumina Novaseq technology. Comparative transcriptome analysis of adult male and female gonads identified a large number of differentially expressed genes. Among them, many reproduction-related genes that play important roles in gonad differentiation and development were found. These data may contribute greatly to the regulation of rabbitfish reproduction. The rabbitfish, Siganus oramin, is a commercially important table fish in southeastern China. However, there have been few studies on its gonad development and reproduction regulation. Comparative transcriptome analysis was first performed on adult male and female gonads of S. oramin. In total, 47,070 unigenes were successfully assembled and 22,737 unigenes were successfully annotated. Through comparative transcriptome analysis of male and female gonads, a total of 6722 differentially expressed genes were successfully identified, with 3528 upregulated genes and 3154 downregulated genes in the testes. In addition, 39 differentially expressed reproduction-related genes were identified. Finally, quantitative real-time PCR was used to validate the expression levels of several differentially expressed genes. These results provide important data for further studying the function of reproduction-related genes and the molecular mechanism regulating gonad development and reproduction in S. oramin. [ABSTRACT FROM AUTHOR]

• Effects of three variants of microcystins on the intestinal physiological of the shrimp was analyzed. • Intestinal histological morphology and physiological homeostasis was disturbed. • MC-LR stress induced more differential metabolites than that of MC-YR and MC-RR. • Purine metabolism function was affected by the stress of three MCs variants. • The strategies of intestinal amino acid metabolism to the stress of three MCs variants were different. Microcystins (MCs) are harmful substances to the health of cultured shrimp, and there are many variants of MCs. Intestinal is the immune and metabolic center of the shrimp, and is also the target organ for MCs toxicity. In this study, the shrimp Litopenaeus vannamei juvenile were separately exposed to 1 μg/L of three MCs variants (LR, YR, RR) for 72 h respectively, and the changes of intestinal morphology, physiological response and metabolic function were analyzed. The results showed the three MCs variants stress caused intestinal mucosal damage and disordered the homeostasis of antimicrobial genes (ALF and Lys) expression. The mRNA expression levels of antioxidant genes (Nrf2 and GPx) and apoptosis factors (CytC and Casp-3) were increased, but that of detoxification gene (CYP450) was decreased. Furthermore, the intestinal metabolic pattern was also influenced by stresses, among which MC-LR induced more differential metabolites than that of MC-YR and MC-RR. The function of purine metabolism was highly influenced by the stress of three MCs variants, followed by amino acid metabolism, but there were differences in the types of amino acids. The metabolites citric acid, L-glutamine, L-tryptophan, spermine, UMP, and indole contributed to the metabolic pathway network. Nineteen stress-related metabolites were identified as candidates for subsequent screening of potential biomarkers. These results revealed the toxic effects of three MCs variants on the intestinal physiological and metabolic homeostasis of the shrimp. [ABSTRACT FROM AUTHOR]

Simple Summary: Ammonia is a major water quality factor influencing the survival and health of shrimp, among which the gill is the main effector organ for ammonia toxicity. In this study, we explored the toxicity of ammonia stress on the physiological homeostasis in the gills of Litopenaeus vannamei under seawater and low-salinity conditions. This study included four groups, namely the SC group (ammonia-N 0 mg/L, salinity 30‰), SAN group (ammonia-N 10 mg/L, salinity 30‰), LC group (ammonia-N 0 mg/L, salinity 3‰), and LAN group (ammonia-N 10 mg/L, salinity 3‰). The ammonia stress lasted for 14 days. The results show that ammonia stress caused the severe contraction of gill filaments and the deformation or even rupture of gill vessels. Ammonia stress could also influence the redox, ER function, apoptosis, detoxification, energy metabolism, and osmoregulation of the shrimp gills. These results are helpful to analyze the toxicological mechanism of ammonia stress on the seawater- and low salinity-cultured shrimp. Ammonia is a major water quality factor influencing the survival and health of shrimp, among which the gill is the main effector organ for ammonia toxicity. In this study, we chose two types of Litopenaeus vannamei that were cultured in 30‰ seawater and domesticated in 3‰ low salinity, respectively, and then separately subjected to ammonia stress for 14 days under seawater and low-salinity conditions, of which the 3‰ low salinity-cultured shrimp were domesticated from the shrimp cultured in 30‰ seawater after 27 days of gradual salinity desalination. In detail, this study included four groups, namely the SC group (ammonia-N 0 mg/L, salinity 30‰), SAN group (ammonia-N 10 mg/L, salinity 30‰), LC group (ammonia-N 0 mg/L, salinity 3‰), and LAN group (ammonia-N 10 mg/L, salinity 3‰). The ammonia stress lasted for 14 days, and then the changes in the morphological structure and physiological function of the gills were explored. The results show that ammonia stress caused the severe contraction of gill filaments and the deformation or even rupture of gill vessels. Biochemical indicators of oxidative stress, including LPO and MDA contents, as well as T-AOC and GST activities, were increased in the SAN and LAN groups, while the activities of CAT and POD and the mRNA expression levels of antioxidant-related genes (nrf2, cat, gpx, hsp70, and trx) were decreased. In addition, the mRNA expression levels of the genes involved in ER stress (ire1 and xbp1), apoptosis (casp-3, casp-9, and jnk), detoxification (gst, ugt, and sult), glucose metabolism (pdh, hk, pk, and ldh), and the tricarboxylic acid cycle (mdh, cs, idh, and odh) were decreased in the SAN and LAN groups; the levels of electron-transport chain-related genes (ndh, cco, and coi), and the bip and sdh genes were decreased in the SAN group but increased in the LAN group; and the level of the ATPase gene was decreased but the cytc gene was increased in the SAN and LAN groups. The mRNA expression levels of osmotic regulation-related genes (nka-β, ca, aqp and clc) were decreased in the SAN group, while the level of the ca gene was increased in the LAN group; the nka-α gene was decreased in both two groups. The results demonstrate that ammonia stress could influence the physiological homeostasis of the shrimp gills, possibly by damaging the tissue morphology, and affecting the redox, ER function, apoptosis, detoxification, energy metabolism, and osmoregulation. [ABSTRACT FROM AUTHOR]

The present study was conducted to investigate the effects of Haematococcus pluvialis on growth performance, antioxidant capacity, immune responses and resistance to Vibrio harveyi of spotted sea bass Lateolabrax maculatus. Fish were fed with six diets containing grade levels of containing H. pluvialis (0, 2, 4, 6, 8 and 1 g/kg, respectively) in triplicate for 8 weeks, followed by a V. harveyi infection test for 7 days. The astaxanthin concentrations of diets were 1.14 (control), 30.23 (T1), 58.42 (T2), 91.51 (T3), 118.61 (T4) and 150.31 mg/kg (T5). Results showed that dietary H. pluvialis increased final body weight (FBW), weight gain rate (WGR) and specific growth rate (SGR) and decreased the whole body lipid of fish (p <.05). Dietary H. pluvialis improved the hepatic total antioxidant capacity (T‐AOC) and decreased the levels of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) activities, and malondialdehyde (MDA) contents of fish (p <.05). In fish fed the H. pluvialis supplemented diets, the levels of triglyceride, cholesterol and low‐density lipoprotein cholesterol (LDL‐C) contents decreased (p <.05). Moreover, dietary H. pluvialis improved the complement and immunoglobulin (Ig) contents, and lysozyme (LYZ) activities (p <.05). After challenge with V. harveyi, the survival rate in T2, T3, T4 and T5 was significantly higher than that of control, and the highest survival rate was in T3 (p <.05). These results indicated that dietary supplementation with the suitable level (0.4%–0.6%) of H. pluvialis could promote growth performance and hepatic antioxidant capacity, and enhance immune responses and resistance to V. harveyi challenge of L. maculates. [ABSTRACT FROM AUTHOR]

The dual-redundancy permanent magnet synchronous motor (DRPMSM) has high reliability in its applications. Compared with the traditional permanent magnet synchronous motor (PMSM), small teeth were added to the stator in DRPMSM and its vibration has new characteristics. This paper derived the analytic expression of the radial electromagnetic force for PMSM in the air gap based on the Maxwell stress equation and summarized its sources. The simplified stator teeth model of the traditional PMSM and DRPMSM were established in 12-slot/10-pole (12s10p), and the analytical expression and Fourier expansion of radial electromagnetic force on the teeth were given. The electromagnetic and structural finite element models of the motor were established, and analyses of modal and harmonic response were carried out. The simulation results show that the stator vibration amplitude of DRPMSM is smaller than that of traditional PMSM at no-load and is also bigger under rated load. Furthermore, in order to guarantee the low amplitude of stator vibration under rated load for DRPMSM, the width of the small teeth should be smaller. [ABSTRACT FROM AUTHOR]

Seven graded levels of sodium propionate (SP) diets with 0 (SP1), 0.2% (SP2), 0.4% (SP3), 0.6% (SP4), 0.8% (SP5), 1.0% (SP6), and 1.2% (SP7) were prepared to feed Trachinotus ovatus (initial body weight: 8.64 ± 0.08 g) for 56 days. The results showed that increasing dietary SP levels quadratically increased significantly final body weight (FBW), weight gain rate (WGR), and specific growth rate (SGR) of T. ovatus but linearly and quadratically decreased significantly viscerosomatic index (VSI) and hepatosomatic index (HSI) of T. ovatus (P < 0.05). In the SP4 treatment, FBW, WGR, and SGR presented the highest values. Both positive linear and quadratic trends were detected between crude lipid content of whole fish, adhesiveness of dorsal muscle, white blood cell (WBC), red blood cell (RBC), hemoglobin (HGB), blood performance, high-density lipoprotein cholesterol (HDL-c), intestinal villus height, and dietary SP level, while negative linear and quadratic trends were found between firmness of dorsal muscle, triglyceride (TG), glucose (GLU), and dietary SP level (P < 0.05). The increasing SP led to quadratic increases in lymphocyte (Lym), complement 3 (C3), chymotrypsin, villus number, and muscle layer thickness, and a quadratic decrease in hepatic malondialdehyde (MDA P < 0.05). A significant negative linear trend was found between the content of glutamic-pyruvic transaminase (GPT) and dietary SP level, while significant positive linear trends were presented between C4, immunoglobulin M (IgM), α-amylase and dietary SP level (P < 0.05). The increasing SP resulted in linear and quadratic increases in superoxide dismutase (SOD), total antioxidant capacity (T-AOC) of livers and C3, C4, IgM of head kidney (P < 0.05). The expression levels of tumor necrosis factor alpha (TNF-α) and interleukin-8 (IL-8) were linearly and quadratically decreased, while the mRNA levels of growth factor beta (TGF-β) were linearly and quadratically increased with the increasing SP level (P < 0.05). In conclusion, SP could be considered as a beneficial feed additive for enhancing growth and immunity of fish. And dietary SP level at 0.6% is optimal for the growth of Trachinotus ovatus based on a quadratic regression model of WGR. [ABSTRACT FROM AUTHOR]

The aim of this experiment was to investigate the effects of the partial substitution of fish meal with soybean products and chicken meal on the growth performance, antioxidant capacity and intestinal microbiota of Penaeus monodon. A total of 450 healthy, consistent shrimp were randomly divided into five groups, with three replicates per group and 30 shrimp per replicate. The proportion of fish meal substituted with soybean products and chicken meal in the five feed groups was 0% (FM), 40% (40SC), 60% (60SC), 80% (80SC) and 100% (100SC). The experiment lasted for 8 weeks. The results showed that, compared to the FM group, the 40SC and 60SC groups had a decrease in WG and SR, but there was no significant difference (p > 0.05). In contrast, compared to the FM group, the FCR in the 100SC group was significantly increased (p < 0.05), while there was no significant difference among the FM and 40SC, 60SC and 80SC groups (p > 0.05). Compared to the FM group, the ACP in the 80SC and 100SC groups significantly increased (p < 0.05), while the 40SC and 60SC groups had no significant difference (p > 0.05). The AKP in the 100SC group was significantly higher than that in the FM group (p < 0.05), while there were no significant differences among the other four groups (p > 0.05). There were no significant differences in T-AOC and T-SOD among all the treatment groups (p > 0.05). The next-generation sequencing of the intestinal microbiota showed that Proteobacteria was the most abundant phylum in the five groups, accounting for 37.67%, 66%, 40%, 40% and 43.33%, respectively. Compared to the FM group, the Fusobacteriota in the other four groups decreased significantly (p < 0.05). The functional prediction of FAPROTAX indicated that no functional components were observed which are harmful to the body. Considering the effects on growth performance, antioxidant capacity and intestinal microbiota, it is feasible to use soybean products and chicken meal to replace 60% of fish meal in the feed of P. monodon. [ABSTRACT FROM AUTHOR]

The essential oil of Magnolia denudate (MDO) is an effective anesthetic and sedative on spotted seabass (Lateolabrax maculatus). To improve animal welfare and transportation effectiveness, this study evaluated the effects of MDO on water quality, blood biochemical, and tissue damage after the transportation of L. maculatus (164.16 ± 15.40 g). A base group (no MDO and no transport) and 0 (control group), 10, and 20 mg/L MDO during simulated transportation treatments of 5 h were involved. Every treatment has four replicates with four fish transported in a plastic box (34 × 22.5 × 19 cm) with 5 L water at a fish density of 130 g/L and a shake rate of 60 rpm. At the end of the transportation simulation, no mortality was observed. Fish were immediately sampled for blood collection, liver and brain removal. Compared to the control group, the MDO groups showed significantly lower ammonia in water, lower cortisol level and lactic dehydrogenase activity, higher glucose, aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase activities in fish serum (p < 0.05). Superoxide dismutase (SOD), catalase (CAT) activity, glutathione (GSH) concentration decline, and malondialdehyde (MDA) were alleviated in the fish brain when MDO was added to the water. However, SOD and GSH further decreased, but MDA increased in the fish liver in the MDO groups (p < 0.05). These results revealed that the administration of MDO on L. maculatus transportation could alleviate stress and decrease energy metabolism. Due to the 20 mg/L MDO may trigger more serve liver function decline, we suggest 10 mg/L MDO addition in L. maculatus transportation. • Transportation caused stress and increased energy metabolism in Lateolabrax maculatus. • The administration of essential oil of Magnolia denudata improved water quality in transportation. • The administration of essential oil of M. denudata alleviated stress and energy metabolism. [ABSTRACT FROM AUTHOR]

To improve the accuracy of three-dimensional (3D) surface contour measurements of freeform optics, a two-dimensional (2D) tilt measurement sensor for confocal microscopy (CM) systems is proposed based on a double-cylindrical mirror structure. First, the proposed system is accurately modeled. Second, we introduce a modified mean–shift-based peak-extraction algorithm with a novel kernel function (MSN) because the reflectivity of the measured object and fluctuation of the light source affect the measurement accuracy. Third, a partition fitting (PF) strategy is proposed to reduce the fitting error and improve the measurement accuracy. Simulations and experiments reveal that the robustness, speed, and angular prediction accuracy of the system effectively improved as a function of MSN and PF. The developed sensor can measure the 2D tilt, where each tilt is a composition of two separate dimensions, and the mean prediction errors in the 2D plane from −10°–+10° are 0.0134° (0.067% full scale (F.S)) and 0.0142° (0.071% F.S). The sensor enables the optical probe of a traditional CM to obtain accurate and simultaneous estimates of the 2D inclination angle and spatial position coordinates of the measured surface. The proposed sensor has potential in 3D topographic reconstruction and dynamic sampling rate optimization for 3D contour detection. [ABSTRACT FROM AUTHOR]

Supercapacitors, as a new type of green electrical energy storage device, are a potential solution to environmental problems created by economic development and the excessive use of fossil energy resources. In this work, nitrogen/oxygen (N/O)-doped porous carbon materials for high-performance supercapacitors are fabricated by calcining and activating an organic crosslinked polymer prepared using polyethylene glycol, hydroxypropyl methylcellulose, and 4,4-diphenylmethane diisocyanate. The porous carbon exhibits a large specific surface area (1589 m2·g−1) and high electrochemical performance, thanks to the network structure and rich N/O content in the organic crosslinked polymer. The optimized porous carbon material (COCLP-4.5), obtained by adjusting the raw material ratio of the organic crosslinked polymer, exhibits a high specific capacitance (522 F·g−1 at 0.5 A·g−1), good rate capability (319 F·g−1 at 20 A·g−1), and outstanding stability (83% retention after 5000 cycles) in a three-electrode system. Furthermore, an energy density of 18.04 Wh·kg−1 is obtained at a power density of 200.0 W·kg−1 in a two-electrode system. This study demonstrates that organic crosslinked polymer-derived porous carbon electrode materials have good energy storage potential. [ABSTRACT FROM AUTHOR]

Microcystins (MCs) are prevalent harmful contaminants within shrimp aquaculture systems, exhibiting a diverse array of variants. Gut microbiota can engage in mutual interactions with the host through the gut-liver axis. In this study, the shrimp Litopenaeus vannamei were subjected to three different variants of MCs (LR, YR, RR) at a concentration of 1 μg/L each, and elucidated the alterations in both intestinal microbiota and hepatopancreas physiological homeostasis. The results showed that all three variants of MCs prompted histological alterations in the hepatopancreas, induced elevated levels of oxidative stress biomarkers (H 2 O 2 , T-SOD, and CAT), disturbed the transcription levels of immune-related genes (Crus , ALF , and Lys), along with an increase in apoptotic genes (Casp-3 and P53). Furthermore, the metabolic profiles of the hepatopancreas were perturbed, particularly in amino acid metabolism such as "lysine degradation" and " β -alanine metabolism"; the mTOR and FoxO signaling were also influenced, encompassing alterations in the transcription levels of related genes. Additionally, the alterations were observed in the intestinal microbiota's diversity and composition, particularly potential beneficial bacteria (Alloprevotella , Bacteroides , Collinsella , Faecalibacterium , and Prevotellaceae UCG-001), which exhibited a positive correlation with the metabolite berberine. These findings reveal that the three MCs variants can impact the health of the shrimp by interfering with the homeostasis of intestinal microbial and hepatopancreas physiology. [Display omitted] • The homeostasis of oxidative stress, antimicrobial and apoptosis were affected in the hepatopancreas. • Lysine degradation and β -alanine metabolism were disturbed in the hepatopancreas. • The metabolism and gene transcription related to mTOR and FoxO signaling have been influenced. • Intestinal microbial diversity, community composition, and metabolic function were disturbed. • Several intestinal bacteria exhibited a positive correlation with the metabolite berberine of the host. [ABSTRACT FROM AUTHOR]

Six isonitrongenous and isolipidic diets were formulated to feed 360 fish (mean initial body weight: 6.06 ± 0.02 g) with graded levels of sodium acetate (SA1 (0), SA2 (250 mg/kg), SA3 (500 mg/kg), SA4 (1000 mg/kg), SA5 (2000 mg/kg), and SA6 (4000 mg/kg)) for 8 weeks. The results revealed that weight gain rate, specific growth rate, and feed intake of golden pompano were significantly increased in SA3 and SA4 treatments (p < 0.05). Dietary SA level significantly improved lipid contents and gumminess of muscle (p < 0.05). Supplement levels of dietary SA significantly influenced plasma biochemical parameters containing triglyceride, glucose, high-density lipoprotein cholesterol, complements, and immunoglobulin M (p < 0.05). Appropriate supplement levels of dietary SA significantly increased enzyme activities of hepatic superoxide dismutase and total antioxidant capacity and decreased malondialdehyde contents (p < 0.05). Furthermore, appropriate SA levels downregulated the expression levels of Keap1, IL-8, TNF-α, and NF-κB genes and upregulated the expression levels of Nrf2 and TGF-β genes of the spleen (p < 0.05). Excess SA caused negative effects for Trachinotus ovatus. The optimum supplement level of SA for juvenile golden pompano was evaluated to be 1423.67 mg/kg based on WGR. [ABSTRACT FROM AUTHOR]

Triclocarban (TCC) is a widely used broad-spectrum antimicrobial agent that has become a pollutant threatening the health of aquatic animals. However, the toxic effects of TCC on Penaeus monodon are still lacking. In this study, we exposed P. monodon to 1 μg/L (TCC-1) and 10 μg/L TCC (TCC-10) for 14 days, and the changes of histological morphology, physiological and immune responses in the gills were investigated. The results showed that TCC exposure caused the deformation of the gill vessels and the disordered arrangement of the gill filaments. Oxidative stress biochemical indexes such as H 2 O 2 content, CAT and GPx activity and the relative expression levels of antioxidant-related genes (SOD , GPx and Nrf2) were increased in the TCC-1 and TCC-10 groups; the levels of CAT and HSP70 genes were increased but POD activity was decreased in the TCC-10 group. The relative expression levels of endoplasmic reticulum (ER) stress indexes such as ERP15 and ATF-6 genes were increased in the TCC-10 group, while the level of GRP78 gene was decreased in the TCC-1 and TCC-10 groups. The relative expression levels of apoptosis indexes such as p53 and JNK genes were increased, but CytC and Casp-3 genes were decreased in the TCC-1 and TCC-10 groups. Furthermore, the relative expression levels of detoxification metabolism-related genes (cytP450 and GST) and osmotic regulation-related genes (NKA-α , NKA-β , CA , AQP , CLC and CCP) were increased in the TCC-10 group. The results showed that TCC exposure could affect the physiological homeostasis in the gills of P. monodon , probably via damaging histological morphology, inducing oxidative stress, and disordering ER stress, apoptosis, detoxification and osmotic regulation. • The toxic effect of triclocarban (TCC) on Penaeus monodon was evaluated for the first time. • TCC exposure damaged the normal histological morphology of the gills tissue. • TCC exposure induced the oxidative stress response and affected the antioxidant capacity. • TCC exposure disordered ER stress, apoptosis, detoxification and osmotic regulation homeostasis. [ABSTRACT FROM AUTHOR]

The Dual-Redundancy Permanent Magnet Synchronous Motor (DRPMSM) with weak thermal coupling and no electromagnetic coupling among phase windings has two sets of three-phase symmetrical windings. Under normal conditions, two sets of windings can operate simultaneously, and once one set has an inter-turn short circuit fault (ISCF), the other set will operate alone, so a DRPMSM can be applied in fields with high reliability requirements. According to the equivalent circuit principle, a simplified model of a DRPMSM when ISCF occurs is established in this paper, and mathematical equations for the equivalent resistance, inductance and induction electromotive force (EMF) are derived. Based on the simplified circuit principle and instantaneous power theory, combined with the analysis of the fundamental wave in the two sets, an online diagnosis method of the ISCF for DRPMSM is proposed based on the reactive power difference and the feasibility of the method is verified by experiments. [ABSTRACT FROM AUTHOR]

Molecular dissection of disease resistance against Vibrio harveyi infection in yellow drum at the genome-wide level uncovered a C-type lectin-like receptor cluster of differentiation CD302 (named as YdCD302) in our previous study. Here, the gene expression pattern of YdCD302 and its function in mediating the defense response to V. harveyi attack were investigated. Gene expression analysis demonstrated that YdCD302 was ubiquitously distributed in various tissues with the highest transcript abundance in liver. The YdCD302 protein exhibited agglutination and antibacterial activity against V. harveyi cells. Binding assay indicated that YdCD302 can physically interact with V. harveyi cells in a Ca2+-independent manner, and the interaction can activate reactive oxygen species (ROS) production in the bacterial cells to induce RecA/LexA-mediated cell death. After infection with V. harveyi , the expression of YdCD302 can be up-regulated significantly in the main immune organs of yellow drum and potentially further trigger the cytokines involved innate immunity. These findings provide insight into the genetic basis of the disease resistance trait in yellow drum and shed light on the functioning of the CD302 C-type lectin-like receptor in host-pathogen interactions. The molecular and functional characterization of YdCD302 is a significant step towards a better understanding of disease resistance mechanisms and the development of new strategies for disease control. [ABSTRACT FROM AUTHOR]

The present study investigated the effects of dietary Spirulina platensis supplementation on growth performance, hematological and serum biochemical parameters, hepatic antioxidant status, immune responses and resistance to the pathogen infection in Coral trout Plectropomus leopardus. The fish were fed for 8-week with diets containing different levels of S. platensis : 0% (C), 2% (SP2), 4% (SP4), 6% (SP6), 8% (SP8) and 10% (SP10) as treatment groups, followed by a Vibrio harveyi infection test for 14 d. The study indicated that dietary supplementation with Spirulina platensis could significantly improve growth performance, and the highest weight gain rate (WGR) and specific growth rate (SGR) were observed in group SP10 ( P  < .05). Red cell count (RBC), white cell count (WBC), hemoglobin (Hb) and total antioxidant capacity (T-AOC) in the S. platensis supplemented groups were significantly higher than those of group C ( P  < .05). However, the levels of cholesterol, triglyceride and malondialdehyde (MDA) contents, and superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) activities decreased with the increasing of dietary S. platensis levels. Compared with group C, the lysozyme (LYZ) and respiratory burst activities (RBA), and immunoglobulin (Ig) and complement contents in group SP4, SP6, SP8 and SP10 increased significantly than those of group C respectively ( P  < .05). After challenge with V. harveyi , the survival rate in group SP4, SP6, SP8 and SP10 was significantly higher than that of group C, and the highest survival rate was in group SP10 ( P  < .05). These results indicated that P. leopardus fed a diet supplemented with S. platensis (especially at 10%) could significantly promote its growth performance, improve its hepatic antioxidant status, and enhance its immune ability and resistance to V. harveyi infection. [ABSTRACT FROM AUTHOR]

Short-chain fatty acids (SCFAs) have been widely applied in aquaculture. Previous studies mainly focused on phenotypic level involved in the trophic function of SCFAs. Integration of intestinal microbiota and lipidomic and transcriptomics responses could deepen our understanding of the underlying mechanism of SCFAs. This study was performed to investigate the influences of sodium acetate (SA) on intestinal health of juvenile golden pompano (Trachinotus ovatus). Two isonitrogenous and isolipidic diets, including the control (C) group and SA group were fed to juvenile golden pompano (average weight 8.68 ± 0.07 g) for 8 weeks. The results showed that dietary SA significantly increased the activities of intestinal chymotrypsin, lipase and α-amylase enzymes as well as intestinal villus number and intestinal wall thickness (P < 0.05), while intestinal pH significantly decreased (P < 0.05). SA supplement significantly increased levels of butyric acid, valcric acid and caproic acid (P < 0.05) and significantly decreased levels of acetic acid, propionic acid and isvalcric acid (P < 0.05). SA supplementation significantly promoted intestinal microbiota alpha diversity and regulated microbial community composition by increasing the abundances of putatively beneficial bacteria such as Turicibacter and Labrenzia (P < 0.05). Besides, SA supplementation changed the lipid profile of intestinal metabolites through remodeling the abundances of Glycerolipids, Glycerophospholipids and Sphingolipids. SA supplementation promoted the upregulation of differential genes in "immune system process", "transcription regulator activity", "PI3K-Akt signaling pathway", "Endocytosis", "AMPK signaling pathway" and "Tight junction" (P < 0.05). This study provides a further insight into view for the benefit of SA on gut health of golden pompano. • Sodium acetate (SA) improved digestive enzymes activities and intestinal morphology of Trachinotus ovatus. • SA induced the alteration of intestinal short-chain fatty acids. • SA increased intestinal microbiota diversity and the abundances of beneficial bacteria. • SA remodeled the lipid profile of intestinal metabolites and affected the intestinal immune and metabolic gene transcription. • Intestinal bacteria were correlated with the intestinal lipid molecular changes. [ABSTRACT FROM AUTHOR]