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An asymmetric cyanation of propargylic C–H bonds via a copper-catalyzed radical relay has been developed, in which the propargylic radical was formed via a photoredox-catalyzed intramolecular 1,5-HAT process.

The unhealthy category eigenvector library is constructed by adaptive sample library, and the unhealthy category model is constructed on this basis to realize the filtering of unhealthy webpages. Our expermient proves that this mode can filter unhealthy webpage at higher speed and satisfying precision.

The openness and globalization of the Internet make the information spread on the network mixed, and all kinds of advertisements, spam, reactionary, obscene, violence and other bad information seriously interfere with the normal use of the Internet by Internet users. This paper studies the workflow of the web page bad information filtering system, analyzes the functional modules of the filtering system, and designs the network data processing, text data processing and adaptive processing modules in detail.

The first enantioselective copper-catalyzed cyanation of propargylic C-H bonds via radical relay was established using novel BoxOTMS ligands, providing an efficient and straightforward tool for the construction of structurally diverse chiral allenyl nitriles in good yields with excellent enantioselectivities. This reaction features high functional group tolerance and mild conditions. In addition, the chiral allene products can be readily converted to other chiral compounds via axis-to-center chirality transfer.

Lipid metabolism disorders are found ubiquitously in farmed fish and occur as a result of excessive fat accumulation. Previous studies have found that miR-33 is involved in lipid metabolism; however, its role in fish lipid metabolism is unclear. We sought to clarify this relationship in grass carp in vivo and in vitro. Our findings revealed the length of miR-33 to be 65 bp. Phylogenetic tree analysis showed that grass carp miR-33 was most closely related to fish miR-33 (Siganus canaliculatus). Hepatocytes transfected with miR-33 mimic displayed markedly raised TG content (P

Fourier-transform ghost imaging (FGI) provides a feasible approach to realize high-resolution x-ray imaging of noncrystalline sample. However, the polychromatic characteristic of laboratory x-ray s...

The GH (growth hormone)/IGFs (insulin-like growth factors) system has an important function in the regulation of growth. In this system, IGFBPs play a crucial regulatory role in IGF functions. As a member of the IGFBP family, IGFBP2 can bind to IGF and regulate IGF functions to regulate development and growth. In addition, IGFBP2 shows key regulatory functions in cell proliferation and metabolism. In this study, the igfbp2 gene was cloned from grass carp (Ctenopharyngodon idellus) liver. The ORF of grass carp igfbp2 is 834 bp long and encodes 277 amino acids. The tissue distribution results showed that igfbp2 is expressed in multiple tissues in grass carp and has a high expression level in the liver. In the OGTT, igfbp2 expression was significantly decreased in the liver and brain after 6 h of treatment with glucose. In vitro, igfbp2 expression in grass carp's primary hepatocytes was significantly suppressed by insulin after treatment for 6 and 12 h. Moreover, igfbp2 expression was markedly increased in a dose-dependent manner with glucagon incubation in grass carp's primary hepatocytes. To the best of our knowledge, this is the first report about Igfbp2 in grass carp. These results will provide a basis for the in-depth study of grass carp Igfbp2.

Exosomes are important for intercellular "cross talk", but the role of exosomes in communication between hepatocytes and C. idella kidney (CIK) cells remains unknown. In this study, we detected the changes in factors related to immune and oxidative stress to investigate the molecular mechanism by which fatty hepatocyte-derived exosomes (OA-Exos) reduced immunity and induced oxidative stress in CIK cells. After incubation of CIK cells by OA-Exos for 24 h, tumor necrosis factor-α (TNF-α), nuclear factor-κB (NF-κB) and interleukin-1β (IL-1β) were significantly upregulated in the OA-Exos group (P0.05), and Mn superoxide dismutase (Mn-SOD) and heme oxygenase-1 (HO-1) were significantly downregulated (P0.05). Surprisingly, miR-122 expression was also significantly elevated after OA-Exos incubation. We further identified the expression of miR-122 and found that it was notably increased in OA-Exos compared to hepatocyte-derived exosomes (Exos). Then we transfected CIK cells with miR-122 mimic, consistently, the expression of inflammatory cytokines was also significantly elevated (P0.05), and the expression of glutathione peroxidase (GPx), HO-1, and Mn-SOD were dramatically decreased (P0.05). Furthermore, HO-1 was improved to be a direct target of miR-122, and transfection with HO-1 siRNA indicated that changes in inflammatory cytokines and genes related to oxidative stress were consistent with the above results of CIK cells incubated with OA-Exos and miR-122 mimic. We concluded that OA-Exos may, through the miR-122/HO-1 pathway, reduce immune function and antioxidant defence in CIK cells.

Adiponectin plays critical roles in the regulation of energy metabolism in mammals. However, its roles in fish remain to be evaluated. In this study, we examined the tissue distribution characteristics of two adiponectin genes, namely, adipoqa and adipoqb, at transcriptional level, and detected the changes of their mRNA expressions during oral glucose tolerance test (OGTT). Furthermore, we prepared recombinant proteins of grass carp adiponectin A and adiponectin B and studied their roles in the regulation of glucose metabolism in the hepatopancreas of grass carp in vivo. The results showed that adipoqa mRNA was mainly expressed in the heart of grass carp, followed by red muscle, white muscle, and adipose tissue, while adipoqb mRNA was highly expressed in adipose tissue, red muscle, and white muscle. The mRNA levels of adipoqa and adipoqb in the white muscle and heart were significantly decreased at 1 h post OGTT, and their expressions in the heart were also suppressed at 3 h, whereas the transcriptional levels of adipoqa and adipoqb in the red muscle were elevated significantly at 12 h after glucose load. Intraperitoneal injection of adiponectin A or adiponectin B reduced basal serum glucose levels of grass carp and caused an increase of glycogen content in the hepatopancreas. Adiponectin A upregulated the expression of enzyme genes related to glycolysis (gk and pk) and glycogen synthesis (gys) in the hepatopancreas, and adiponectin B promoted the expression of pk and gys, as well as g6pase in the glycogenetic pathway. Besides, adiponectin A and adiponectin B have opposite regulatory effects on glut2 mRNA expression. These results suggested that adiponectin A and adiponectin B promoted glycolysis, gluconeogenesis, and glycogen synthesis, increased glycogen content of hepatopancreas, and reduced basal blood glucose level, and they may have an antagonistic regulatory mechanism in regulating glucose uptake.

Polyethylene microplastics (PE-MPs) and glyphosate (GLY) occur widely and have toxic characteristics, resulting in increased research interest. In this study, common carp were used to assess the individual and combined toxicity of PE-MPs (0, 1.5, or 4.5 mg/L) and GLY (0, 5, or 15 mg/L) on the brain-gut axis. After 60 days of exposure, the developmental toxicity, blood-brain barrier (BBB), locomotor behavior, intestinal barrier (physical barrier, chemical barrier, microbial barrier), and intestinal content metabolism of common carp were evaluated. Results showed that 15 mg/L of GLY exposure significantly reduced the mRNA expression of tight-junction genes (occludin, claudin-2, and ZO-1) in the brain, and acetylcholinesterase (AChE) activity was clearly inhibited by high concentrations of GLY. However, different concentrations of PE-MPs had no significant effect on the activity of AChE. Furthermore, the free-swimming behavior of common carp was distinctly inhibited by treatment with a combination of 15 mg/L GLY and 4.5 mg/L PE-MPs. Histological studies indicated that PE-MPs alone and in combination with GLY could disrupt the physical and chemical intestinal barriers of common carp. Additionally, the abundance and diversity of gut microbiota in common carp were significantly changed when exposed to a combination of PE-MPs and GLY. Metabolomics further revealed that PE-MPs combined with GLY triggered metabolic changes and that differential metabolites were related to amino acid and lipid metabolism. These findings illustrate that exposure to PE-MPs or GLY alone is toxic to fish and results in physiological changes to the brain-gut axis. This work offers a robust analysis to understand the mechanisms underlying GLY and MP-induced aquatic toxicity.

Apelin and its receptor apj have a variety of biological functions and are involved in appetite and energy regulation. However, the comparative studies of apelin/apj system in fish are still absent. In this study, the open reading frames of apelin and apja and apjb were obtained. Apelin and apj mRNAs were widely distributed in all tissues detected, with the highest level in the brain, followed by the spleen, kidney and foregut. The mRNA expression of apelin and apjs increased rapidly at mealtime and significantly decreased after 30 min of feeding. In addition, there were obvious circadian rhythms (higher at nighttime and lower at daytime) in the expression of apelin and apja and apjb. Furthermore, fasting elevated the mRNA levels of apelin and apjs in the hypothalamus, foregut and hepatopancreas. When the 8‐day fasted fish were refed, apelin and apjs mRNA expression significantly decreased. However, there were differences in the response to fasting and refeeding between apja and apjb. The roles of apelin and its receptor apjs in fish are poorly understood. Herein, we employed molecular and physiological studies to characterize their structures, distribution and mRNA expression responses to periprandial changes and fasting–refeeding in Cyprinus carpio L. for the first time.

The Chinese yam peel (CYP) is a by-product of yam processing that is rich in various nutrients and a good source for feed additives. This study investigated the effects of CYP on the intestinal microbiota and gut defence barrier of the common carp (Cyprinus carpio L.). Different groups of experimental fish were fed a normal control diet (NC), a low CYP diet (LYP) and a high CYP diet (HYP) for 8 weeks. After the feeding trial, the fish were assessed for intestinal enzyme activity, intestinal histology, immune-related gene expression, intestinal SCFAs and intestinal microbiota. Our results indicated that the intestinal integrity and antioxidant enzyme (CAT and SOD) activity in the common carp were enhanced following CYP supplementation. The mRNA levels of anti-inflammatory (TGF-β), tight binding protein (occludin and ZO-1) and pathway factor genes (TLR4 and NF-κB) were significantly upregulated in the HYP group (P＜0.05), which was accompanied by an increase in the level of pro-inflammatory IL-1β in the gut (P＜0.05). High-throughput sequencing revealed that Fusobacteria, Proteobacteria, and Bacteroidetes bacteria were most abundant in the microbial community in the gut of the common carp. The relative abundances of Bacteroides, Flavobacterium and Lactobacillus were increased, while the abundances of pathogenic microorganisms such as Enterobacteriaceae, Shewanella, Pseudomonas and Vibrio were reduced after treatment with CYP. Furthermore, the concentrations of acetic acid, propionic acid, butyric acid and total short-chain fatty acids (SCFAs) in the gut were also increased (P＜0.05). Finally, our results revealed correlations between gut microbiota, SCFAs, non-specific immunity and antioxidant enzymes in CYP-fed carp. These results suggest that CYP-supplemented feed could improve the immunity of the common carp by modulating the intestinal microflora and enhancing the gut defence barrier and has the potential to be used as an immunostimulating feed additive in aquaculture.

Above-threshold ionization (ATI) is one of the most fundamental processess when atoms or molecules are subjected to intense laser fields. Analysis of ATI process in intense laser fields by a Wigner-distribution-like (WDL) function is reviewed in this paper. The WDL function is used to obtain various time-related distributions, such as time-energy distribution, ionization time distribution, and time-emission angle distribution and so on, of atoms in laser field pulses with different laser parameters. For the linearly polarized laser pulses, the time-energy distribution intuitively shows from a quantum point of view the relationship between the ionization moment and the final energy and clearly reveals the origin of interference structures in the photoelectron spectrum. In particular, for linearly polarized few-cycle laser pulses, all calculated distributions show the dependence of electron behavior on the ionization time, emission direction, and carrier-envelope phase (CEP). For elliptically polarized few-cycle pulses, we calculate the angular distribution, ionization time distribution, and time-emission distribution, which are compared with the semiclassical calculations. Analysis shows that the offset angle (difference between positions of the peaks in the angular distributions obtained by two methods) in the angular distributions does not correspond to the offset time (difference between positions of the peaks in the ionization time distributions obtained by two methods) in the ionization time distributions, which implies that the attosecond angular streaking technique based on this correspondence between the offset angle and time is in principle inaccurate. Furthermore, the offset time cannot be interpreted as tunneling time.

X-ray diffractive microscopy is a powerful tool in exploring the inner structures of non-crystalline complex samples. However, highly coherent x-ray sources are essential in traditional x-ray diffractive microscopy. Fourier-transform ghost imaging provides the feasibility of achieving high-resolution diffractive imaging with spatially incoherent sources. By taking advantage of the non-local modulation characteristic of ghost imaging, coded Fourier-transform patterns of a sample can be obtained at the Fresnel region and better phase retrieval can be achieved. Here we present our progress on a tabletop x-ray diffractive microscopy system based on Fourier-transform ghost imaging.

This study investigated the effects of honeysuckle extract (Lonicera japonica, HE) on the growth performance and lipid metabolism of juvenile grass carp (Ctenopharyngodon idella). HE at doses of 10 g kg−1 (LHE), 20 g kg−1 (MHE), and 40 g kg−1 (HHE) were individually mixed with the basal diet and fed to grass carp for 10 weeks, and ginseng extract (20 g kg−1, GSE) was used as a positive control. The results showed that HE administration exerted no effect on growth performance, but the hepatosomatic index (HSI) and muscle and liver lipid contents were significantly decreased in the LHE and MHE groups. The serum levels of LDL-c, total triglyceride (TG) and total cholesterol (TC) also declined in the HE-treated groups. Moreover, the disordered vacuolization and nucleus migration in the liver were alleviated in the MHE and HHE groups, and mRNA expressions of lipogenesis-related genes, such as acc1, fas, srebp1, and pparγ decreased. Similarly, the expression of genes related to lipolysis, such as cpt1, atgl, lpl, and pparα, was found to be significantly increased in the MHE and HHE groups compared with the control. Taken together, HE can effectively improve the lipid metabolism and ameliorate the lipid deposition of grass carp and thus may be a promising feed additive in aquaculture.

We use the improved strong-field approximation (ISFA) theory to investigate the evolution of the energy spectra with the carrier-envelope phase (CEP) of a few-cycle laser pulse. The theoretical calculations are consistent with the experimental measurements performed by Lindner et al (2005 Phys. Rev. Lett. 95 040401) which can be attributed to the scattering electrons whose ionization rates are modulated by the CEP of the laser pulse. We further investigate the dynamic behavior of the relevant scattering electrons by a Wigner distribution-like function based on the ISFA. Our analysis indicates that the zeroth-return forward-scattering electrons that move directly to the parent ion after tunneling and scatter forward with the parent core play a key role in the energy range of 2U p ∼ 4U p and the backward-scattering electrons are responsible for the high-energy region. Meanwhile, it is found that the contribution of the second-return backward-scattering electron to the middle energy spectrum is also important in the few-cycle laser field case.

We use a Wigner distribution-like function based on the strong field approximation theory to obtain the time-energy distributions and the ionization time distributions of electrons ionized by an XUV pulse alone and in the presence of an infrared (IR) pulse. In the case of a single XUV pulse, although the overall shape of the ionization time distribution resembles the XUV-envelope, its detail shows dependence on the emission direction of the electron and the carrier-envelope phase of the pulse, which mainly results from the low-energy interference structure. It is further found that the electron from the counter-rotating term plays an important role in the interference. In the case of the two-color pulse, both the time-energy distributions and the ionization time distributions change with varying IR field. Our analysis demonstrates that the IR field not only modifies the final electron kinetic energy but also changes the electron’s emission time, which is attributed to the change of the electric field induced by the IR pulse. Moreover, the ionization time distributions of the photoelectrons emitted from atoms with higher ionization energy are also given, which show less impact of the IR field on the electron dynamics.

Our objective is to study the low metabolic utilization of dietary carbohydrates in fish. The regulation of key enzymes involved in glucose and lipid metabolism in the common carp (Cyprinus carpio L.), known to be relatively tolerant to dietary carbohydrates, were assessed. We performed intraperitoneal (i.p.) administration of insulin and glucagon to common carp and also subjected common carp primary hepatocytes to insulin or glucagon. The results showed that insulin administration induced hypoglycaemia through up-regulation of the expression of the glycolysis genes glucokinase (GK) and hexose kinase (HK), coupled with increased gene expression of fatty acid synthase (FAS), acetyl-CoA carboxylase-1 (ACC-1), sterol-regulator element-binding protein-1 (SREBP-1). Insulin also limited the expression of the gluconeogenesis genes phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase), coupled with decreased gene expression of lipoprotein lipase (LPL) and carnitine palmitoyl transferase I (CPT-1). However, glucagon had the opposite effect. The results showed that glucagon induced hyperglycemia with increased expression of PEPCK and G6Pase and increased lipolytic capacity as indicated by lower mRNA levels of SREBP-1. Glucagon (i.p.) significantly increased the activity of PEPCK and LPL in hepatopancreas. In addition, the mRNA expression of HK showed an up-regulated trend and the mRNA expression of PEPCK and G6Pase showed a down-regulated trend in the group of glucose (i.p.). This study demonstrates that insulin and glucagon possess the intrinsic ability to regulate hepatic energy metabolism in common carp, the regulation of which seems to be similar to that of the mammals at least at the molecular level.

Recently, the concept of precision nutrition has emerged in aquaculture, and there is increasing discussion on this topic. Some researchers have defined precision nutrition as precision feeding, which means that the nutrient contents of feed should meet the requirements for an animal’s optimal production performance and achieve minimum fodder waste at the same time. In practice, precision nutrition should include a comprehensive survey of the animal’s genetic background, living habits, metabolic characteristics, water ecological environment and other factors. Precision nutritional regulation covers every level, from genes, cells, and tissues to the whole organism. Through interacting with genes, nutrients activate or inhibit signalling pathways/networks within cells, which regulate gene expression and protein synthesis and subsequently affect the composition, content and deposition sites of carbohydrates, lipids, proteins and trace elements. Therefore, we propose that precision nutritional intervention needs to be carried out from the perspectives of ‘precision feeding’, ‘precision metabolism’, ‘precision output’ and ‘precision support’ simultaneously. This review intends to elaborate the concept evolution, theoretical system, and composition of the technical system, together with other aspects of precision nutritional regulation. This knowledge will provide a theoretical reference for the sustainable development of the aquaculture industry and the harvesting of quality products.

Abnormal lipid metabolism in the liver due to excessive fat accumulation is a widespread problem in fish. MicroRNA-122 (miR-122), a liver-specific miRNA in vertebrates, is involved in lipid metabolism. In this study, miR-122 was cloned, and its function was investigated in grass carp. MiR-122 is 99 bp in length, showing 70 % similarity to that of other species and is specifically expressed in liver tissue. After transfection with miR-122 agomir for 24 h in liver cells, we found that the overexpression of miR-122 significantly increased the TG content in cells (P < 0.05), while the expression level of transcription factors related to lipid synthesis was significantly increased (P < 0.05). After injection of miR-122 agomir in vivo, the TG content in the liver increased significantly (P < 0.05), and the mRNA expression of lipid synthesis-related genes (PPARγ, SREBP-1c, ACC, FAS and H-FABP) increased significantly (P < 0.05). The relative expression of the proinflammatory factors TNF-α, IL-6, and IL-1β also increased significantly (P < 0.05), while the relative abundance of the anti-inflammatory factors IL-10 and TGF-β1 decreased significantly (P < 0.05). In addition, we found that miR-122 regulated lipid catabolism-related genes through AMPK, and AMPK may regulate lipid synthesis-related genes through miR-122 directly or indirectly. In summary, the comparison of miRNA-122 from genomic sequences reveals strong conservation of miRNA-122 across vertebrate classes; however, its function shows species-specific actions in grass carp and mammalian models. This study provides basic data for further investigation of a miRNA related to fatty liver and other metabolic diseases.

A Wigner distributionlike function based on the improved strong-field approximation theory is proposed to calculate the rescattering time-energy distribution (RTED) of high-energy photoelectrons of atomic above-threshold ionization process in few-cycle laser fields with different frequencies. The RTED shows bell-like stripes and the outermost stripe is compared with semiclassical results given by the simple-man model with consideration of different positions of tunnel exit and different initial longitudinal momenta. Analysis indicates the existence of the tunnel exit. However, though it shifts farther away from the core with decreasing frequency, the position of the tunnel exit is significantly less than the prediction by adiabatic theory even for the low-frequency case which is well in the tunneling regime. Our results also imply that the effect of the tunnel exit is more important than that of the initial longitudinal momentum at the tunnel exit for the backward-scattering electrons. Moreover, the inner stripe structures in the RTED are attributed to interference between electrons with the same final energy emitted at different ionization times.

A ligand-controlled system that enables regioselective trifluoromethylcyanation of 1,3-enynes has been identified, which provides access to a variety of CF3 -containing tri- and tetrasubstituted allenyl nitriles. We disclose that the involved propargylic radicals can be selectively trapped by (Box)CuII cyanide, while the tautomerized allenyl radicals are trapped by (phen)CuII cyanide (Box= bisoxazoline, phen=phenanthroline). In addition, the reaction features broad substrate scope and excellent functional group compatibility. Moreover, this protocol represents a novel regioselectivity-tunable functionalization of 1,3-enynes via radicals, which we believe will have great implications for the development of catalytic systems for selectivity control in radical and organometallic chemistry.

As the incretin hormone, Glucose-dependent insulinotropic peptide (GIP) plays an important role in lipid metabolism, glucose uptake, and bone metabolism in mammals. To evaluate the roles of GIP in the teleost, the gip gene was isolated from the foregut of grass carp by RT-PCR. The ORF of grass carp gip was 327 bp and encodes 108 amino acids. And the mature peptide of grass carp was 31 amino acids. The tissue distribution results showed that gip mRNA was highly expressed in the gut, and was also at high levels in the spleen and brain region. In the oral glucose tolerance test (OGTT), the gip expression was significantly increased in foregut by glucose treatment for 1 and 3 h. The primary hepatocytes and intraperitoneal injection studies showed that the glut2, g6pase, pepck, acc1, fas, hsl, lpl expression were increased and the gk and cpt1 expression were decreased by GIP treatment. And the expression of pi3k, akt and pka were also increased by GIP treatment. In the primary hepatocytes, the effects of GIP on g6pase, glut2, lpl and cpt1 expression were relieved by Wortmannin (PI3K inhibitor), and the effects of GIP on pepck, gk and hsl expression were alleviated by H89•2HCl (PKA inhibitor). And glucose and triglyceride (TG) contents are promoted in primary hepatocytes by GIP treatment. In the intraperitoneal injection experiment, the serum glucose, total cholesterol (T-CHO) and low-density lipoprotein cholesterol (LDL-C) contents were reduced, and serum TG and high-density lipoprotein cholesterol (HDL-C) contents were elevated after GIP injection. Our studies for the first time unveil the potential role of GIP as a regulatory factor of glucose and lipid metabolism in teleost.

The co-transport of sodium and glucose is the first step for intestinal glucose absorption. Dietary glucose and sodium chloride (NaCl) may facilitate this physiological process in common carp (Cyprinus carpio L.). To test this hypothesis, we first investigated the feeding rhythm of intestinal glucose absorption. Carps were fed to satiety once a day (09:00 a.m.) for 1 month. Intestinal samples were collected at 01:00, 05:00, 09:00, 13:00, 17:00 and 21:00. Result showed that food intake greatly enhanced sodium/glucose cotransporter 1 (SGLT1) and glucose transporter type 2 (GLUT2) expressions, and improved glucose absorption, with highest levels at 09:00 a.m.. Then we designed iso-nitrogenous and iso-energetic diets with graded levels of glucose (10%, 20%, 30%, 40% and 50%) and NaCl (0%, 1%, 3% and 5%), and submitted to feeding trial for 10 weeks. The expressions of SGLT1 and GLUT2, brush border membrane vesicles (BBMVs) glucose transport and intestinal villus height were determined after the feeding trial. Increasing levels of dietary glucose and NaCl up-regulated mRNA and protein levels of SGLT1 and GLUT2, enhanced BBMVs glucose transport in the proximal, mid and distal intestine. As for histological adaptive response, however, high-glucose diet prolonged while high-NaCl diet shrank intestinal villus height. Furthermore, we also found that higher mRNA levels of SGLT1 and GLUT2, higher glucose transport capacity of BBMVs, and higher intestinal villus were detected in the proximal and mid intestine, compared to the distal part. Taken together, our study indicated that intestinal glucose absorption in carp was primarily occurred in the proximal and mid intestine, and increasing levels of dietary glucose and NaCl enhanced intestinal glucose absorption in carp.

Epithelial brush-border membrane vesicles (BBMVs) were isolated from the intestine of common carp and studied systematically by enzyme activity, transmission electron microscopy and immunoblotting. The uptake time course and the substrate concentration effect were assessed, and then, the ability of phlorizin and cytochalasin B to inhibit uptake was analyzed. The results show that sucrase, alkaline phosphatase and Na+-K+-ATPase activities in these vesicles were enriched 7.94-, 6.74- and 0.42-fold, respectively, indicating a relatively pure preparation of apical membrane with little basolateral contamination. The vesicular structure was in complete closure, as confirmed by electron microscopy. The presence of SGLT1 on the BBMVs was confirmed by Western blot analysis. In the time course experiment, the glucose uptake by BBMVs in Na+ medium displayed an initial accumulation (overshoot) at 5 min followed by a rapid return to equilibrium values at 60 min. Over the 2-NBDG concentration range selected, the external 2-NBDG concentration in NaSCN medium graphed as a curved line. Phlorizin and cytochalasin B had an obvious inhibitory effect on 2-NBDG transport in carp BBMVs, and the detected fluorescence intensity decreased. The inhibition rate in the 1000 μM group was the strongest at 64.18% and 63.61% of phlorizin and cytochalasin B, respectively, indicating the presence of carriers other than SGLT1. This study is the first to demonstrate that 2-NBDG can be used as a convenient and sensitive probe to detect glucose uptake in fish BBMVs. This technology will provide a convenient method to discover new effects and factors in glucose metabolism.

As the major non-protein energy sources, high carbohydrate (CHO) and lipid (L) diets have been widely used in aquaculture to reduce cost, but they also caused excessive lipid accumulation in the fish liver. It is not yet clear which, lipid or carbohydrate, is a greater influence on hepatic lipid accumulation. To study the effects of dietary carbohydrate and lipid levels on hepatic lipid deposition in Nile tilapia ( Oreochromis niloticus ), six diets with different carbohydrate and lipid levels (carbohydrate level ranged from 11.2% to 54.24%, while lipid level ranged from 21.51% to 2.70%, namely, the dietary CHO:L ratios ranged from 0.52:1 to 20.09:1) were formulated and fed to tilapia for 8 weeks. After the feeding trial, high specific growth rate (SGR) was observed in the groups with the CHO:L ratio of 1.95, 3.41 and 6.40. Hepatosomatic and viscerosomatic index increased as dietary CHO:L ratios increased. Low serum TG, CHL and HDL levels was observed in the groups with the CHO:L ratio of 6.40 and 20.09. Hepatic histology showed that the fish fed with dietary CHO:L ratios of 3.41 and 6.40 have more hepatic lipid droplets than fish fed with other diets. Hepatic gene expression data indicated that the cd36 transcript levels were significantly affected by dietary CHO:L ratios, with the highest expression in fish fed D4 and D5 with CHO:L ratio of 3.41 and 6.40. Higher transcript levels of lipogenic genes ( fas , acc-α and dgat2 ) were observed in the liver of fish fed with high CHO:L ratio diets, whereas FA β-oxidation genes ( cpt1 and acox1 ) expression were depressed in liver. Hepatic apoB100 expression was also down-regulated with the high dietary CHO:L ratios. These results suggested that dietary carbohydrates have a stronger effect on hepatic lipid accumulation than dietary lipids in tilapia. High dietary CHO:L ratios (> 3.41) accelerated the hepatic lipid deposition by increasing de novo lipogenesis and reducing FA β-oxidation and lipoprotein clearance in the liver, and diet with around 1.95 CHO:L ratio is suitable for tilapia culture concerning the growth performance and health. The present results will be of great significance in improving the utilization of dietary lipid and carbohydrate to achieve better nutrition efficiency in tilapia.

The distribution of fat among both invertebrate and vertebrate groups is heterogeneous. Studies have shown that fatty acid‐binding proteins (FABPs), which mainly bind and transport fatty acids, play important roles in the regulation of fat storage and distribution. However, the systematic and genome‐wide investigation of FABP genes in organisms with a heterogeneous fat distribution remains in its infancy. The availability of the complete genomes of Caenorhabditis elegans, Callorhinchus milii, and other organisms with a heterogeneous fat distribution allowed us to systematically investigate the gene structure and phylogeny of FABP genes across a wide range of phyla. In this study, we analyzed the number, structure, chromosomal location, and phylogeny of FABP genes in 18 organisms from C. elegans to Homo sapiens. A total of 12 types of FABP genes were identified in the 18 species, and no single organism exhibited all 12 fatty acid‐binding genes (FABPs). The absence of a specific FABP gene in tissue may be related to the absence of fat storage in the corresponding tissue. The genomic loci of the FABP genes were diverse, and their gene structures varied. The results of the phylogenetic analysis and the observation of conserved gene synthesis of FABP family genes/proteins suggest that all FABP genes may have evolved from a common ancestor through tandem duplication. This study not only lays a strong theoretical foundation for the study of fat deposition in different organisms, but also provides a new perspective regarding metabolic disease prevention and control and the improvement of agricultural product quality., To clarify the relationships between fatty acid‐binding proteins (FABPs) and the tissues in which fat is deposited, the number, gene structure, conserved synteny, and evolution of FABP family genes in 18 species were systemically studied. In total, 142 FABPs were identified. The absence of a specific FABP gene in tissue may be related to the absence of fat storage in the corresponding tissue.

To address the problem of low-carbon operation enthusiasm of Online shopping supply chains based on O2O mode, first, the carbon emission model of supply chain members is constructed by the adjusting cost and production functions, and the corresponding incentive model is constructed according to the carbon emission trading system. Second, the incentive model is solved and analyzed based on the optimal emission reduction cost and the optimal carbon emission incentive. Finally, optimal control theory is used to analyze the dynamic optimization of the model. The result shows that with the improvement of anastomosis in Online and offline operations, the emission reduction cost is reduced. Supply chain members need to reduce carbon emissions only when their business scale is more than a certain amount. The cost of emission reduction for supply chain members is a concave function of the cost for its operation equipment or the correct emission price.

A demand function of online shopping supply chain based on online-to-offline (O2O) fusion degree is proposed by considering the low-carbon awareness of online shoppers in view of the low-carbon decision making of supply chain in combination with the O2O operation background. On this basis, a low-carbon decision-making model based on online stores and their suppliers is established, and the application of the model is analyzed. Results show that the promotion of low-carbon operation is efficient when the consistency of online and offline operations of online stores and their suppliers is high. In addition, the decision making considering the cost of carbon information release is highly conducive to improving the low-carbon awareness of online shoppers if the low-carbon level of online shopping goods is lower than the low-carbon standard. Accordingly, the low-carbon operation of online shopping supply chain will be promoted.

To explore the mechanism of fatty liver formation induced by high non-protein energy diets in grass carp (Ctenopharyngodon idella), basal diet and high-energy diets were fed to juvenile grass carp for 9 weeks. The experimental groups fed on high-energy diets which included a high-lipid diet (H-LIP), a high-carbohydrate diet (H-CHO) and a high-lipid and carbohydrate diet (H-CL). The control group fed on basal diet. Growth performance, liver fat accumulation, serum biochemical indexes and the expression levels of lipid metabolism-related genes (SREBP-1, PPARγ, FAS, ACC1, and LPL) and miRNAs (miR-33, miR-122, and miR-370) were examined at the end of the feeding trial. There were no significant differences in growth rate and feed efficiency among the four groups. However, significant increase in mesenteric and liver fat contents, and lipid droplets in the liver was induced by high-lipid and high-carbohydrate diets. There were significant differences in serum biochemical indicators such as AST/ALT, GLB, TG and TP, and liver fatty acid composition between the control and experimental groups. The expression levels of SREBP-1, PPARγ, FAS, ACC1 and LPL were upregulated, while CPT-1 was downregulated with the high-energy treatments. Additionally, the expression levels of miR-33, miR-122 and miR-370 in the liver were higher in the three high-energy treatments than those in the control (P