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A new copolyesters of poly(2-[4-(2-hydroxyethoxy)phenoxy]ethyl-co-1,4-cyclohexylenedimethylene terephthalate) (PHCT) with different compositions were synthesized from terephthalic acid, 1,4-cyclohexanedimethanol and hydroquinone bis(2-hydroxyethyl) ether (HQEE) via esterification-polycondensation reaction. The synthesized copolyesters were analyzed by 1H-NMR, FT-IR, GPC, intrinsic viscosity, DSC, TGA and tensile testing, respectively. The 1H-NMR and FT-IR analysis confirm the successful introduction of HQEE into poly(1,4-cyclohexylenedimethylene terephthalate (PCT) chains. The introduction of HQEE into PCT chains can effectively lower the melting point of PCT, making it easier to process. The glass transition temperature of PHCT is higher than 70 ℃ and it has the comparable thermal stabilities to PCT. In addition, introducing HQEE into PCT chains can effectively improve the molecular weights of PCT, thus imparting PHCT with better mechanical performance relative to PCT. The PHCT is a tough polymer, which owns the higher Young's modulus (above 300 MPa), the higher tensile strength (above 39 MPa) and the higher elongation at break (above 226%). [ABSTRACT FROM AUTHOR]

A new copolyesters of poly(1,4-cyclohexylenedimethylene terephthalate-co-4,4'-biphenydicarboxylate) (PCTB) with different compositions were synthesized from terephthalic acid, 1,4-cyclohexanedimethanol and 4,4'-biphenyldicarboxylic acid (BDA) via esterification-polycondensation reaction. The synthesized copolyesters were analyzed by 1H-NMR, 13C-NMR, FT-IR, GPC, intrinsic viscosity, DSC, TGA and tensile testing, respectively. The 1H-NMR, 13C-NMR and FT-IR results verify the successful introduction of BDA into poly(1,4-cyclohexylenedimethylene terephthalate (PCT) chains. The introduction of BDA into PCT chains can effectively lower the melting point of PCT, making it easier to process. The glass transition temperature of PCTB is higher than 103 °C and its thermal stability is better than that of PCT. The rheological tests confirm the enhanced melting stability of PCT after introducing BDA into PCT chains. Furthermore, the PCTB, which owns the comparable mechanical properties to PCT, is a tough polymer with the higher Young's modulus (above 230 MPa), the higher tensile strength (above 41 MPa) and the higher elongation at break (above 159%). [ABSTRACT FROM AUTHOR]

For power system transient stability assessment (TSA), the consequences of misclassifications of unstable samples are more serious than those of stable samples. Therefore, the cost-sensitive method is introduced into TSA. A constant weight is set for all unstable training samples by the conventional cost-sensitive method. However, the fault severities of the training samples are different. Thus, the impacts of the samples with different fault severities on assessment rules are also different. Therefore, an improved cost-sensitive method based on the fault severity is proposed. Firstly, the fault severity of each sample is calculated by its fault clearing time. On this basis, different cost-sensitive coefficients are assigned to the samples with different fault severities. The weights of critical samples are larger than those of non-critical ones. Then, a stacked sparse auto-encoder model based on the improved cost-sensitive method is built through modifying the loss function. Finally, the proposed method is tested in an actual system. Compared with the traditional cost-sensitive method, the results show that the improved cost-sensitive method has better performance. Also, it has the advantages of the low false rate of unstable samples, high-assessment accuracy, and strong anti-noise ability. [ABSTRACT FROM AUTHOR]

For power system transient stability assessment (TSA), the consequences of misclassifications of unstable samples are more serious than those of stable samples. Therefore, the cost‐sensitive method is introduced into TSA. A constant weight is set for all unstable training samples by the conventional cost‐sensitive method. However, the fault severities of the training samples are different. Thus, the impacts of the samples with different fault severities on assessment rules are also different. Therefore, an improved cost‐sensitive method based on the fault severity is proposed. Firstly, the fault severity of each sample is calculated by its fault clearing time. On this basis, different cost‐sensitive coefficients are assigned to the samples with different fault severities. The weights of critical samples are larger than those of non‐critical ones. Then, a stacked sparse auto‐encoder model based on the improved cost‐sensitive method is built through modifying the loss function. Finally, the proposed method is tested in an actual system. Compared with the traditional cost‐sensitive method, the results show that the improved cost‐sensitive method has better performance. Also, it has the advantages of the low false rate of unstable samples, high‐assessment accuracy, and strong anti‐noise ability. [ABSTRACT FROM AUTHOR]

• PISBFs were prepared from 2,5-dimethylfuran dicarboxylate, isosorbide and butanediol. • PISBFs had T D,5% values higher than 370 °C and T DM higher than 405 °C. • PIS 40 B 60 F had a Tg 87 °C, a Young's modulus 1400 MPa and an elongation at break 173%. Fully biobased copolyesters poly(isosorbide- co -butylene 2,5-furandicarboxylate) (PISBF) were synthesized from 2,5-dimethylfuran dicarboxylate (DMFD), isosorbide (IS) and 1,4-butanediol (BDO) via transesterification and polycondensation reactions. The resulting copolymers were characterized by 1H NMR, 13C NMR, GPC, intrinsic viscosity, DSC, TGA and tensile testing, respectively. The NMR characterizations had confirmed that BDO was successfully introduced into the poly(isosorbide 2,5-furandicarboxylate) (PIF) polyester chains. Over the IS experimental composition range 20–80 % in copolymer chains, PISBF copolymers had T D, 5% values higher than 370 °C and T DM higher than 405 ° C, and Tg values within the range of 55 °C and 150 °C. Introduction of BDO units into PIF chains imparted the PISBF copolyester with better mechanical performance than PIF, thus PISBF copolyesters with IS content of 20–50% were strong and toughened copolymers with Young's modulus about 1400 MPa, tensile strength at break higher than 53 MPa, and elongation at break higher than 46%. [ABSTRACT FROM AUTHOR]

A series of bio-based copolyesters, poly(ethylene 2,5-furandicarboxylate-co-ethylene 1,4-cyclohexanedicarboxylate)s (PEFCs) were synthesized from ethylene glycol (EG), 2,5-furandicarboxylic acid (FDCA) and 1,4-cyclohexanedicarboxylic acid (CHDA) through a two-step melt polycondensation procedure. The chemical structure, compositions and sequence distributions were determined by 1 H NMR. The molecular weight, thermal properties, thermal stabilities, crystal structure and mechanical properties were investigated by GPC, DSC, TGA, WAXD, and tensile testing, respectively. All PEFCs showed the characteristic of random copolymer, and their composition could be controlled by the feed molar ratio of FDCA to CHDA. DSC results showed that PEFCs were amorphous, while increasing the content of the CHDA unit, the glass transition temperatures (Tg) of PEFCs decreased. Moreover, the thermal stabilities of all PEFCs remained unchanged. The tensile testing demonstrated that PEFC-30 was a toughened plastic with tensile modulus 801 MPa and elongation 667%. [ABSTRACT FROM AUTHOR]

• The fault severity of each sample is calculated as an additional label to participate in the training process. • The differences of samples with different fault severities are considered. • The idea of dynamic adjustment is applied for transient stability assessment. • An adaptive cost-sensitive assignment method is presented, which is robust to abnormal training samples. In power system transient stability assessment (TSA), the misclassification cost of unstable samples is much more serious than that of stable ones. Besides, for both unstable samples and stable samples, the impacts of critical samples on the assessment rules are more important than those of non-critical ones. Thus, an improved cost-sensitive assignment (ICSA) method based on the fault severity is proposed. Larger cost coefficients are assigned to critical samples compared with non-critical samples. Furthermore, sufficiently learning the information of misclassified samples is helpful to modify the assessment rules quickly and accurately. Meanwhile, the assessment rules may be greatly disturbed due to the existence of abnormal samples among training samples. Therefore, on basis of the ICSA method, an adaptive cost-sensitive assignment (ACSA) method is presented in this paper. In the process of model training, the cost coefficients of misclassified training samples are adaptively adjusted to improve the assessment rules. Then, the impacts of the abnormal samples on the assessment rules are eliminated by assigning their cost coefficients to 0. Finally, simulation experiments are carried out in the IEEE 39-bus system and a realistic system. It can be shown that the proposed ACSA method has high classification accuracy and excellent generalization ability. [ABSTRACT FROM AUTHOR]

Copolycarbonate was synthesized by melt transesterification method, using diphenyl carbonate, isosorbide and 1,4-cyclohexanedimethanol (CHDM) as raw materials. The copolymer composition and random structure of the copolymer were determined by Fourier transform infrared and 1H NMR analysis. The DSC and TGA analysis showed that CHDM was introduced into the isosorbide polycarbonate chain, which effectively lowered the glass transition temperature of the polymer without lowering the thermal decomposition temperature. The glass transition temperature of the copolymer can be controlled by the addition amount of CHDM, and its processing performance can be improved. In addition, the introduction of CHDM did not reduce the high light transmittance (> 91.5%) of isosorbide polycarbonate. With the gradual increase of the amount of CHDM added, the refractive index of the copolymer decreases slightly. When the CHDM content is 30 mol%, the glass transition temperature (Tg)of the copolymer is 132.2 °C, the thermal decomposition temperature is > 350 °C, the refractive index is 1.4960, the Abbe number is 51, and the transmittance is 91.6%, and the haze is 1.07%. [ABSTRACT FROM AUTHOR]

Abstract: Hatchery releases of the prawn (shrimp), Penaeus chinensis, have been made in China for 20 years, both within and outside the natural distribution of the species. The number of released prawns reached a peak of 5.213 billion in 1991 and currently remains at ∼600 million p.a., providing annual landings of around 720t. Catches of released prawns have contributed >90% to total landings in one region, the Haiyangdao Fishing Ground in the north Yellow Sea. Although recapture rates of hatchery released juveniles varied greatly between release sites, they reached an average of 9.2% at the Haiyangdao Fishing Ground from 1985 to 1992, and 9% in Xiangshan Bay from 1984 to 1995 and 5.4% in Dongwuyang Bay from 1986 to 1995, two bays in the East China Sea. The ratio of production costs to revenue from the catches of released prawns reached 1:8.5 for the stock enhancement programmes in the Yellow Sea, and averaged 1:5.6 in the translocation of prawns outside their natural range in the East China Sea. Although releases of hatchery-reared prawns in China have succeeded in augmenting production of commercial prawn fisheries, they have not increased the size of the wild prawn populations in the Yellow-Bohai Sea region due to over-fishing of pre-spawning animals. Similarly, they have not succeeded in establishing self-replenishing populations in areas when P. chinensis was translocated outside its natural distribution. Instead, the various prawn stock enhancement initiatives have led to successful sea ranching operations, i.e., releasing juveniles and harvesting them when they reach market size but before they reach sexual maturity. However, rebuilding the wild prawn stock through management regulations promises to be a more cost-effective approach to increasing prawn production than the current sea ranching operations. ‘Put and take’ releases are an inappropriate substitute for more urgently needed fisheries management actions, such as habitat restoration and reduction in fishing effort, and management to allow releases of hatchery-reared prawns to contribute to spawning biomass. [Copyright &y& Elsevier]

• NBA Schiff Base with NO 2 was first synthesized to prepare fire-safety PET (NBA n PET). • NO 2 in NBA n PET passivated reactivity to enhance its cross-linking temperature. • NBA accelerated the reaction of polycondensation of NBA n PET to save preparing time. • NO 2 improved the residue char of NBA n PET in the fire to improve flame retardancy. A new Schiff base flame retardant monomer with nitro group (NO 2), 5-((4-nitrobenzylidene) amino) isophthalic acid (NBA) was firstly synthesized to prepare fire-safety PET copolyester (NBA n PET). The group of NO 2 passivated the cross-linking reactivity of Schiff Base by affecting the formation of the intermediate states of the cross-linking reaction and further to improve the cross-linking temperature of NBA n PET to the temperature range (347–372 °C) from that of (250–348 °C), which showed better machinability in a broad processing temperature zone. In additional findings, the new synthesized NBA Schiff Base helped to shorten the time of polycondensation of PET with the advantage to save 58% of the reaction time by its acid structure. And the group of NO 2 enhanced the thermal stability of NBA n PETs, which improved its residue char in high temperature to enhance its flame retardancy. NBA 10 PET with NBA (7.9 mol%) processed LOI of 32% and V-0 of UL-94 without drip. The analysis of mechanism showed that the group of NO 2 in NBA did not decompose into the gas phase and NBA performed the mechanism of condensed phase during combustion of Schiff Base modified PET. The newly prepared NBA n PET with these better properties could possess wider application prospects. [ABSTRACT FROM AUTHOR]

In this study, silica-gel (SG)-supported deep eutectic solvent (DES) with a different loading dosage as the novel nanocomposite materials has been synthesized by sol–gel method. And the supported nanocomposite materials were used as the catalyst for the synthesis of 1,10-phenanthroline from the 8-aminoquinoline and acrolein. The properties and structure of catalysts were characterized by Fourier transform infrared, N2 adsorption–desorption, scanning electron microscopy, thermogravimetric analysis and elemental analysis techniques. It was found that the 12%DES/SG catalyst with the best catalytic activity possessed the suitable specific surface area 132 m2/g and 12% loading amount of DES, which combines the excellent properties of mesoporous materials and DES. The result of thermogravimetric analysis was exhibited that the nanocomposite materials could not be decomposed below 240 °C, which can be used as a stable catalytic material under reaction conditions. Furthermore, the effect of reaction parameters such as reaction temperature and catalyst amount, molar ratio of 8-aminoquinoline and acrolein and reaction time was also studied. Under the optimal process parameters, within the optimum parameters: 130 °C, acrolein: 8-AQ = 2:1, catalyst amount 20 wt%, and time 4 h, the conversion of 8-aminoquinoline and selectivity of 1,10-phenanthroline were 83.8% and 84.3%, respectively. Otherwise, the catalyst can be separated from the reaction system and reused. Therefore, the silica-gel-supported deep eutectic solvent nanocomposite materials can be considered as a potential catalytic material for the synthesis of 1,10-phenanthroline and other nitrogen-containing heterocyclic organic chemical intermediates. Replacing traditional sulfuric acid and hydrochloric acid with silica-gel-supported deep eutectic solvents as new nanocomposite catalysts provides a more efficient, greener and more economical strategy for the synthesis of 1,10-phenanthroline. [ABSTRACT FROM AUTHOR]

Bio-based poly(isosorbide 2,5-furandicarboxylate-co-ε-caprolactone) (PIFCL) copolyesters were synthesized from 2,5-furandicarboxylic acid, isosorbide and ε-caprolactone. The obtained copolyesters were characterized by 1H NMR, 13C NMR, intrinsic viscosity, GPC, DSC, TGA and tensile testing. The NMR characterization results confirmed the insertion of lactones units into poly(isosorbide 2,5-furandicarboxylate) (PIF) chains. All PIFCL copolyesters were amorphous with T D, 5% higher than 300 °C. The glass transition temperatures of PIFCLs with FDCA molar ratio from 74% to 45% were within the range of 132.1 °C and 72.4 °C. Tensile testing revealed that introduction of ε-caprolactone into PIF chain imparted PIFCL with excellent mechanical performance, typically, PIFCL polyseter with FDCA molar ratio of 45% had a Young's modulus 858 ± 92 MPa, a tensile strength 44 ± 4 MPa and an elongation at break 480 ± 45%. Image 1 • Bio-based poly(isosorbide 2,5-furandicarboxylate-co-ε-caprolactone) (PIFCL) copolymers were prepared via copolymerization. • PIFCL80 had a T g 72.4 °C, a Young's modulus 858 ± 92 MPa, a tensile strength 44 ± 4 MPa and an elongation as high as 480 ± 45%. • All PIFCL copolyesters were amorphous with T D, 5% higher than 300 °C. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Bio-based poly(ethylene 2,5-furandicarboxylate- co -ε-caprolactone)s (PEFCLs) were prepared via copolymerization. • PEFCL40 had a Young's modulus 1182 ± 80 MPa, a tensile strength 51 ± 3 MPa and an elongation as high as 981 ± 117%. • The modified materials maintained good thermal stability. Abstract A new bio-based copolyesters, poly(ethylene 2,5-furandicarboxylate- co -ε-caprolactone) (PEFCL), were synthesized from 2,5-furandicarboxylic acid, ethylene glycol and ε-caprolactone. The obtained copolyesters were characterized in terms of chemical structures, thermal and mechanical properties. The characterization results of 1H NMR and 13C NMR had confirmed the insertion of lactones units in PEF chains, all PEFCL copolyesters showed random microstructures. These bio-based copolymers were amorphous and had one glass transition temperature decreased as increasing the CL content. The thermal stability of PEFCL is slightly lower than PEF. Tensile testing revealed that introduction of ε-caprolactone into PEF chains impart PEFCL with excellent mechanical performance, typically, PEFCL40 had a Young's modulus 1182 ± 80 MPa, a tensile strength 51 ± 3 MPa and an elongation as high as 981 ± 117%. [ABSTRACT FROM AUTHOR]

Copolymer carbonate was synthesized from diphenyl carbonate (DPC), 9, 9‐bis [3‐phenyl‐4 ‐(2‐hydroxyethoxy) phenyl] fluorene (BPPEF) and 2,2′ ‐bis (2‐hydroxy‐ethoxy)‐1,1′ ‐binaphthalene (BHEBN) by melt transesterification. The composition and random structure of the copolymer were determined by FT‐IR, 1H NMR and 13C NMR analysis. DSC and TGA analysis showed that Cardo structure could significantly increase the glass transition temperature and thermal decomposition temperature. With the addition of BHEBN, the refractive index of copolymer was increased, but the thermal properties of copolymer were decreased. It is found that the contribution of naphthalene structure to the refractive index of the polymer material is higher than that of benzene structure. When the dosage of BHEBN is 42 mol %, the glass transition temperature (Tg) of the copolymer is 141.8 °C, the maximum thermal decomposition temperature is 421.9 °C, the refractive index is 1.6535, the Abbe number is 21, the transmittance is 88.29 %, and the birefringence is negative 0.01×10−3. [ABSTRACT FROM AUTHOR]

Solid alkali KF/MgO catalysts were prepared using the impregnation method by combining alkali metal compounds with oxides, which performed the transesterification of isosorbide (IS) with dimethyl carbonate (DMC) into dicarboxymethyl isosorbide (DC). Characterization of the catalysts was conducted through X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and N2 adsorption–desorption analysis. The catalytic performance of KF/MgO was examined under diverse KF loading and calcination temperature conditions. The characterization of catalyst identified that the creation of innovative active components K2MgF4 and K2CO3 were produced at a calcination temperature of 500 ℃ and a KF loading amount of 40%. The catalyst of 40-KF/MgO-500 demonstrated the most effective, favourable activity and selectivity. Through the optimization of transesterification process conditions, it was discovered that the yield of DC was at its highest under the optimal reaction conditions of n(DMC)/n(IS) = 6.5, catalyst dosage of 0.21 wt% (relative to IS mass), transesterification temperature of 120 °C, and reaction time of 6 h. [ABSTRACT FROM AUTHOR]

The traditional method for transformer moisture diagnosis is to establish empirical equations between feature parameters extracted from frequency domain spectroscopy (FDS) and the transformer’s moisture content. However, the established empirical equation may not be applicable to a novel testing environment, resulting in an unreliable evaluation result. In this regard, it is acknowledged that FDS combined with machine learning is more suitable for estimating moisture content in a variety of test environments. Nonetheless, the accuracy of the estimation results obtained using the existing method is limited by the algorithm’s inability to generalize. To address this issue, we propose an AdaBoost algorithm-enhanced back-propagation neural network (BP_AdaBoost). This study creates a database by extracting feature parameters from the FDS that characterize the insulation states of the prepared samples. Then, using the BP_AdaBoost algorithm and the newly constructed database, the moisture estimation models are trained. Finally, the results of the estimation are discussed in terms of laboratory and field transformers. By comparing the proposed BP_AdaBoost algorithm to other intelligence algorithms, it is demonstrated that it not only performs better in generalization, but also maintains a high level of accuracy. [ABSTRACT FROM AUTHOR]

Yi-Fei-Jie-Du-Tang (YFJDT) is a traditional Chinese medicine formulation. Our previous studies have demonstrated that YFJDT can be used to treat non-small-cell lung cancer (NSCLC), but its protective effect against NSCLC and its mechanisms remain unclear. In the present study, we evaluated the protective effects and potential mechanisms of YFJDT on a tumor-bearing mouse lung cancer model and A549 cell model. Tumor-bearing mice and A549 cells were treated with YFJDT, tumors were measured during the experiment, and tumor tissues and cell supernatants were collected at the end of the experiment to assess the levels of autophagy and epithelial-mesenchymal transition (EMT)-related proteins. The results showed that YFJDT treatment reduced tumor volume and mass, increased the expression of the autophagy marker LC3, and inhibited EMT-related proteins compared with the model group. Cell survival was reduced in the YFJDT-treated groups compared with the model group, and YFJDT also reduced the migration and invasion ability of A549 cells in a dose-dependent manner. Western blotting detected that YFJDT also upregulated FAT4 in the tumor tissue and A549 cells and downregulated the expression of vimentin. Meanwhile, apoptosis in both tissues and cells was greatly increased with treatment of YFJDT. We further interfered with FAT4 expression in cells and found that the inhibitory effect of YFJDT on EMT was reversed, indicating that YFJDT affects EMT by regulating FAT4 expression. Taken together, results of this study suggested that the inhibitory effect of YFJDT on EMT in lung cancer tumors is through upregulating FAT4, promoting autophagy, and thus inhibiting EMT in cancer cells. [ABSTRACT FROM AUTHOR]

Endocrine disrupting chemicals (EDCs) are increasingly viewed as persistent pollutants, similar to natural hormones in function. This paper describes the expression profiles of 7 genes ( DMRT, VTG GnRHR FSHR CYP17A CYP19A, and CYP19B) involved in sex steroid synthesis and action as well as sexual development in adult male and female Cynoglossus semilaevis, after exposure to different concentrations of Bisphenol A (BPA) and 17β-estradiol (E2). Both BPA (1, 10, 50, 125, and 250 mg/kg) and E2 (0.5, 5, and 10 mg/kg) induced changes in target gene expression, although the estrogenic effects of E2 as a model estrogen were stronger. Among the 7 genes, VTG CYP17A and CYP19 responded strongly to BPA or E2 exposure and can thus serve as reference biomarkers for estrogenic EDCs exposure in marine teleosts. These data will provide a window to establish a hypothalamic-pituitary-gonadal model in C. semilaevis to better understand the effect pathways of EDCs. [ABSTRACT FROM AUTHOR]

Abstract: Fenneropenaeus chinensis is distributed along the coasts of the northern seacoast of China and the Korean Peninsula. According to their migration routes, spawning and overwintering places, F. chinensis is divided mainly into three geographic variety populations. These populations represent potentially different genetic resources important to hybridisation breeding programs. To evaluate heterosis of the total protein concentration (PC), haemocyanin concentration (HC), penoloxidase (PO) activity, acid phosphatase (ACP) activity, alkaline phosphatase (ALP) activity and antimicrobial activity (Ua) mating was produced between and within Yellow and Bo sea (YB) population and southern seacoast of Korean Peninsula (SK) population, and the offspring of 49 families was reared to 7.64g in the controlled environment. The results showed that the content of all haemolymph analytes of SK population was higher than that of YB population, and the immunocompetence in all hybridisations were higher than that in YB♂×YB♀ except of HC in YB♂×SK♀. Nine of 12 hybridisations had manifested positive heterosis in six haemolymph analytes. Heterosis of SK×YB was all-positive, and this hybridisation was better than YB×SK in HC, PO, ALP activity and Ua. The results suggested that the haemolymph analytes of YB and SK populations had many genetic differences, and hybridisation was an important tool to increase immune reaction and adverse resistance. [Copyright &y& Elsevier]

Abstract: This paper presents the genetic linkage map of the Chinese shrimp Penaeus (Fenneropenaeus) chinensis constructed with 472 AFLP markers. A hundred F1 progeny from an intercross between a female from the new variety “Yellow Sea No. 1” and wild caught male used for the mapping study. Two separate maps were constructed for each parent. The female linkage map consisted of 197 marker loci forming 35 linkage groups and spanned a total length of 2191.1 cM, with an average marker space of 13.5 cM. The male map consisted of 194 marker loci mapped to 36 linkage groups and spanned a total length of 1737.3 cM, with an average marker spacing of 11.0 cM. The level of segregation distortion observed in this study was 12.2%. The estimated genome length of P. chinensis was 3150.3 cM for the female and 2549.3 cM for the male, respectively. The observed genome coverage was 69.6% for the female and 68.1% for the male map. The linkage maps constructed in this study provide basic information for further linkage studies on Chinese shrimp, and more importantly, the construction of the maps are part of the work of the genetic breeding programs which will be used for growth discovered in the QTL analysis of P. chinensis. [Copyright &y& Elsevier]

Abstract: Seven AFLP primer sets were used to investigate the genetic structure of a wild base population and three generations of marine shrimp Fenneropenaeus chinensis selected for fast growth (F5–F7). More than 500 bands were generated in total. On average, each primer set detected 33.7 polymorphic markers. The expected average heterozygosity ranged from 0.085 to 0.097. As time under selection increased, genetic diversity tended to reduce, the differentiation between generations became less, and the variation of genetic structure of the populations became smaller. [Copyright &y& Elsevier]

Abstract: The effects of dissolved oxygen (DO) concentration and stocking density on growth performance, such as growth, survival, ecdysis, oxygen consumption, ingestion and food conversion efficiency (FCE), and non-specific immunity factors, such as phenoloxidase (PO), superoxide dismutase (SOD), peroxidase (POD), antibacterial activity (Ua), lysozyme (Ul) were investigated in the Chinese shrimp Fenneropenaeus chinensis. Shrimp growth (gain in length and weight), survival rate, ecdysis, ingestion and FCE were not significantly different among DO concentration treatments. The activities of SOD, POD, Ua, Ul and hemolysin were significantly affected by DO concentration. Mean oxygen consumption was significantly higher under high DO concentration (HDO) compared with medium (MDO) and low DO concentrations (LDO). Shrimp growth (gain in length and weight), survival rate, FCE and the activity of PO enzyme decreased, whereas ingestion and the activity of POD enzyme increased with increasing stocking density. The activity of hemolysin was significantly higher in high stocking density (HSD) compared with medium (MSD) and low stocking density (LSD). There was an interactive effect of DO concentration and stocking density on shrimp weight gain, ecdysis, O2 consumption, ingestion, the activities of Ua and hemolysin. The results revealed that DO concentration was one of the key factors which affecting shrimp through influencing activities of non-specific immunity factors (SOD, POD, Ua, Ul and hemolysin), while stocking density affected the growth performance of shrimp mainly by influencing ingestion or activities of enzymes (PO, POD and hemolysin), and the interactive effects of DO concentration and stocking density (P <0.05) played a crucial role in the production of shrimp farming. [Copyright &y& Elsevier]

In this study, three different choline chloride-based deep eutectic solvents were synthesized. And it is the first time to synthesize 1,10-phenanthroline through an improved Skraup reaction using deep eutectic solvent as the new catalyst from acrolein and 8-aminoquinoline. The deep eutectic solvents were characterized by Fourier transform infrared (FT-IR), 1H nuclear magnetic resonance (1H NMR), pH/mV meter, and thermogravimetric analysis (TGA). The research results show that the deep eutectic solvent formed by sulfanilic acid and choline chloride has the strongest acidity and highest catalytic active among the three deep eutectic solvents. Besides, the impacts of reaction parameters and molar ratio of raw materials on the reaction were also investigated. Under the optimized reaction conditions, the maximum selectivity and yield of 1,10-phenanthroline were achieved as 84.6 and 75.6%, respectively. The synthesis method, meanwhile, also has simple preparation process and low cheaper catalyst raw. Replacing traditional sulfuric acid and hydrochloric acid with deep eutectic solvents (DESs) as new catalysts provides a more efficient, greener and more economical strategy for the synthesis of 1,10-phenanthroline by a new improved Skraup reaction. [ABSTRACT FROM AUTHOR]

pH has a great impact on the distribution, growth, behaviour and physiology in many aquatic animals. MicroRNAs (miRNAs), a class of small non‐coding RNAs play essential roles in animal responses to environmental stress. In this study, we constructed two small RNA (sRNA) libraries from control (pH 7.4) and high pH (9.4) treated shrimp to identify high pH stress‐responsive miRNAs. Using deep sequencing, we identified 72 (3 conserved and 69 novel) up‐ and 4 (2 conserved and 2 novel) down‐regulated miRNAs from high pH challenged shrimp hepatopancreas. Gene Ontology annotations and Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed that these target transcripts were implicated in a broad range of biological processes and various metabolic pathways. Moreover, we validated the expression patterns of selected miRNAs and their target genes by qRT‐PCR. The present work adds new insights into the large‐scale identification and characterization of Fenneropenaeus chinensis miRNAs and their potential targets and represents a foundation for underlying mechanisms of animal responses to high pH stress at post‐transcriptional level. [ABSTRACT FROM AUTHOR]

Mitogen-activated protein kinase (MAPK) signaling pathway plays an important role in cellular response to inflammatory cytokines, environmental stress and pathogenic infection, However, compared with mammals and insects, the potential function of p38 MAPK from Chinese shrimp ( Fenneropenaeus chinensis ) in response to viruses and bacterial infection is limited. In the study, the immune responses of four genes MKK3, MKK4, p38 and ATF-2 from F. chinensis were investigated in defending against white spot syndrome virus (WSSV), Vibrio anguillarum ( V. anguillarum ) and Staphylococcus aureus ( S. aureus ) infection. Results demonstrated that the expression levels of these four genes were apparently modulated in hemocytes and gills when shrimp were stimulated by WSSV or bacteria, particularly at 3–24 h after infection. MKK3, p38 and ATF-2 were most sensitive to V. anguillarum (Gram-negative bacteria), followed by WSSV and S. aureus (Gram-positive bacteria), while MKK4 gene was most sensitive to S. aureus , followed by WSSV and V. anguillarum . Knockdown of Fcp38 by RNA interference (RNAi) resulted in a reduction in the expression of FcMKK3 and FcATF-2 . The results indicate that p38MAPK signaling pathway plays a role in defending against viral and bacterial infections in F. chinensis . [ABSTRACT FROM AUTHOR]

• UiO-66 (Zr/Ti) was used to catalyze the synthesis of PET for the first time. • Through chemical process optimization, PET with a lower b value was successfully synthesized in a 5 L reactor, which provided inspiration for MOF materials in industrial catalysis. • The DFT calculations revealed that the reaction path of UiO-66(Zr/Ti) was more suitable for the coordination of the carboxy oxygen atom mechanism, and the reaction activation energy of 22.37 kacl/mol was close to that of the Sb-based catalyst. PET (poly(ethylene terephthalate)) is one of the most important type of thermoplastic polyesters and widely used in various fields. Titanium-based catalysts are environmentally friendly and have higher catalytic activity than antimony-based catalysts when used in industry. However, titanium-based catalysts are prone to hydrolysis and result in discolored products. UiO-66 (Zr/Ti) with different Ti4+ contents were successfully synthesized via one-step method. The material was characterized by XRD, SEM, FT-IR, XPS, BET and TG techniques. The results demonstrates that Ti4+ was integrated into the UiO-66 framework. NH 3 - in situ DRIFTS, pyridine-IR, and NH 3 -TPD were used to explore the acidic properties of the samples, which proved that stable Lewis acidic sites are present in the samples even at 300 °C. The catalytic performance of UiO-66 (Zr/Ti) containing different Ti4+ was explored under different conditions. At the same time, the scale-up experiment was carried out in a 5 L reactor, and the PET chips obtained had a lower b value. The catalytic reaction mechanism of UiO-66(Zr/Ti) was demonstrated by DFT calculations and the catalytic performance was close to Sb-based catalysts. [Display omitted] [ABSTRACT FROM AUTHOR]

The Huanghai No. 1 strain of Chinese shrimp Fenneropenaeus chinensis is an ecologically and economically important variety that is cultivated mainly in northern China. This strain has been subjected to multiple selective events in recent years. Conventional methods are insufficient to reveal the genetic background of Huanghai No. 1, especially with regard to a genome-wide transcription profile, and publicly available genomic resources for Huanghai No. 1 are limited. We obtained 907,945 original reads with an average length of 467.5 bp from muscle and haemocyte samples from Huanghai No. 1 using 454 pyrosequencing. After preprocessing, 867,245 high-quality reads were screened. Of the 64,830 assembled sequences, 34,633 of the unigenes had significant matches in the databases (similarity >30 %), including 14,138 isotigs and 20,495 singletons. A gene ontology analysis assigned 8,257 unigenes to 44 subcategories, with the majority of unigenes assigned to cellular component (28.2 %), biological process (20.5 %) and molecular function (5.0 %) categories. Pathway mapping based on information in the Kyoto Encyclopedia of Genes and Genomes database showed that 15,461 transcripts were associated with 223 pathways. A total of 14,981 putative SSRs, 72,370 SNPs, and candidate genes involved in growth, reproduction, and the immune response were identified. Our findings represent the most comprehensive transcriptomic resources currently available for Huanghai No. 1, and provide an important foundation for further genomic studies of F. chinensis. [ABSTRACT FROM AUTHOR]

This present study aimed to investigate the effects of inbreeding on growth traits and genetic diversity in the swimming crab, Portunus trituberculatus. To this end, full-sibling inbred groups were established at four levels of inbreeding coefficient ( F values of 0.25, 0.375, 0.5, and 0.5937). The growth traits of the control group ( F ≈ 0) differed significantly from each of the inbred groups at three ages (80, 100 and 120 days old). Significant inbreeding depression was found in all inbred groups ( P < 0.05) and this ranged from −2.55 to −21.75 %, and there was a tendency for inbreeding depression to increase with increasing F value and age. At 120 days old, inbreeding depression was 7.6, 15.30, 16.89 and 21.75 % for the F values of 0.25, 0.375, 0.50 and 0.5937, respectively. Moreover, there was a tendency for inbreeding depression of body weight to increase with the increasing age; for example, inbreeding depression was greater at 120 days compared to that of 80 and 100 days old. Inbreeding depression per 10 % increase in the inbreeding coefficient value ranged from −1.02 to −4.08 %. The genetic parameter (e.g., PIC, n, a, Ho and He values) decreases with the increasing level of inbreeding. The greatest changes in the various genetic results are between the control group and the group ( F = 0.25), thereafter the rate of loss slows. This present study demonstrates that inbreeding has negative effects on growth traits and genetic diversity in P. trituberculatus, thus strengthening the case to maximize genetic diversity in selective breeding programs. [ABSTRACT FROM AUTHOR]

Abstract: Diseases caused by viruses are the greatest challenge to worldwide shrimp aquaculture. C-type lectins may play an important role in shrimp immunity. The gene encoding FcCTL, a C-type lectin-like protein, was isolated from Fenneropenaeus chinensis and characterized. This gene was composed of five exons spanning 2470 base pairs (bp). Intron 1 contained a possible promoter and many potential transcription factor binding sites, such as those for TATA binding protein, CREB, SRF, Ttk and three sites for HSFs. The 5′-flanking sequences (723bp) of FcCTL contained typical CTF (CAAT box) and transcriptional regulatory elements, such as CF1, CF2-II and HSEs, observed in immunity-related genes in other arthropods. A series of FcCTL promoter sequences, especially the full-length promoter, generated an increase in luciferase expression relative to the promoter-less vector; furthermore, the expression of FcCTL was induced by heat shock and white spot syndrome virus (WSSV) challenge. These results extended our previous findings and provided insights into the molecular regulation of FcCTL gene expression, which would be helpful for shrimp viral disease control. [Copyright &y& Elsevier]

Abstract: A simple strategy of colorimetric DNA detection is presented based on a hairpin assembly reaction and target-catalytic DNA circuits to achieve enzyme-free signal amplification. The method employed two hairpin species (H1 and H2), which were stable and unable to hybridize in the absence of target. In the presence of target, the target hybridized with hairpin H1 and the opened hairpin H1 hybridized with hairpin H2, allowing the target to be displaced. H1 and H2 were respectively attached to gold nanoparticles, allowing the duplex formed from H1 and H2 to be visualized with the naked eye. The displaced target again triggered the next round of strand exchange reaction to achieve signal amplification. The method may have a wide range of sensor applications because it is enzyme-free and simple to perform. [Copyright &y& Elsevier]

Abstract: Heat shock protein 90 (HSP90) is a highly conserved molecular chaperone contributing to the folding, maintenance of structural integrity and proper regulation of a subset of cytosolic proteins. In this study, a heat shock protein 90 cDNA named EcHSP90 was cloned from the hepatopancreas of ridgetail white prawn Exopalaemon carinicauda by reverse transcription polymerase chain reaction (RT-PCR) coupled with rapid amplification of cDNA ends (RACE) approaches. The full-length cDNA of EcHSP90 was of 2695 bp, including an open reading frame (ORF) of 2163 bp encoding a polypeptide of 720 amino acids with an estimated molecular mass of 82.73 kDa and an estimated isoelectric point of 4.83. BLAST analysis revealed that the EcHSP90 shared high similarity (87.6%–75.24%) with other known HSP90s. The five conserved amino acid blocks defined as HSP90 protein family signatures were also identified in EcHSP90, which indicated that EcHSP90 should be a cytosolic member of the HSP90 family. Quantitative real-time RT-PCR analysis revealed that EcHSP90 transcript could be detected in all the tested tissues, and strongly expressed in ovary of E. carinicauda. The transcript of EcHSP90 in hepatopancreas of E. carinicauda showed different expression profiles after pH and ammonia-N stresses. The results indicated that EcHSP90 was a constitutive and inducible expressed protein and could be induced by various stresses from environment. [Copyright &y& Elsevier]

Abstract: Four populations of the shrimp, Penaeus chinensis, selected for White Spot Syndrome Virus resistance in breeding programs were examined at eight polymorphic microsatellite loci to assess the levels of allelic diversity and heterozygosity, as well as differentiation among the populations. A total of 71 different alleles were found over all the loci. The total number of alleles per locus ranged from 5 to 16, with allele sizes ranging from 150 to 600bp. The number of genotypes per locus ranged from 5 to 20. The average observed heterozygosities of the G05, G06, G07 and G08 populations were 0.6563, 0.6250, 0.6188 and 0.6188 over all the loci, respectively. The high heterozygosities were maintained through the generations, indicating that there was no significant loss of genetic variability in the breeding program. However, genetic differences among the four populations were detected based on the number of alleles per locus, the effective number of alleles, number of genotypes per locus, frequency of the most common allele, P values, F st values and pairwise F st values. The data showed that as time under selection increased, the differentiation between generations became less, and the variations in the genetic structures of the populations became smaller. The data suggests that there is no detectable change in gene frequencies or heterozygosity over the generations tested, implying that the loci have been unaffected by the selective pressures of culture or that these changes occurred early in culture and prior to G05 generation in culture. [ABSTRACT FROM AUTHOR]

Abstract: A cytosolic manganese superoxide dismutase (cMnSOD) cDNA was cloned from the haemocytes of swimming crab Portunus trituberculatus using reverse transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE) method. Analysis of the nucleotide sequence revealed that the cMnSOD full-length cDNA consisted of 1106bp with an open reading frame of 861bp encoding a protein of 286 amino acids. Four conserved amino acids responsible for binding manganese (H110, H158, D243 and H247) and MnSOD signatures from 243 to 250 (DVWHHAYY) were observed. Sequence comparison showed that the cMnSOD deduced amino acid sequence of P. trituberculatus had similarity of 92%, 78%, 77% and 75% to that of blue crab Callinectes sapidus, white shrimp Litopenaeus vannamei, giant tiger prawn Penaeus monodon and freshwater prawn Macrobrachium rosenbergii, respectively. Quantitative real-time RT-PCR analysis revealed that P. trituberculatus cMnSOD transcript was strongly detected in haemocytes, hepatopancreas, heart, stomach, intestine, gill, ovary and muscle. RT-PCR analysis indicated that cMnSOD transcripts both in haemocytes and hepatopancreas increased at 3h and 6h after infection. These facts indicate that cMnSOD is potentially involved in the acute response against invading bacteria in P. trituberculatus. [ABSTRACT FROM AUTHOR]

Abstract: Phenoloxidase (PO), a melanin-synthesizing enzyme, found as a zymogen (proPO) in hemolymp, plays an important role in arthropod defence. In this study, a prophenoloxidase (proPO) cDNA was cloned from the haemocytes of swimming crab Portunus trituberculatus by a reverse-transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA end (RACE) method. Analysis of the nucleotide sequence revealed that the cDNA clone had a full-length of 3040 bp, with an open reading frame of 2019 bp, a 5′-untranslated region of 138 bp, and a long 3′-untranslated region of 1707 bp. It encoded a protein of 672 amino acids which has a predicted molecular weight of 77.4 kDa and with an estimated pI of 6.19. It is predicted to possess all the expected features of proPO members, including two putative tyrosinase copper-binding motifs with six histidine residues and a proteolytic activation site. Comparison of amino acid sequences showed that the proPO-deduced amino acid of P. trituberculatus has an overall similarity of 56%–87% to that of other crustaceans. Northern blot analysis revealed that the presence of proPO was expressed in haemocytes, hepatopancreas and ovary, but not in eyestalk, gill and muscle. RT-PCR analysis indicated that proPO showed different expression profiles in crab haemocytes and hepatopancreas after Vibrio alginolyticus challenging. These facts indicated that proPO was potentially involved in the acute response against invading bacteria in P. trituberculatus. [Copyright &y& Elsevier]

Abstract: Tissue distribution and elimination of Norfloxacin (NFLX) was evaluated in Japanese sea perch and black sea bream following multi-oral administration. Japanese sea perch and black sea bream were treated with NFLX in seawater at a dose of 30 mg/kg weight body per day for five days in 18.4±0.6 °C and 15.7±1.0 °C, respectively. At different times, six Japanese sea perch and black sea bream were randomly selected from the tank and killed after oral administration. Using high-performance liquid chromatography (HPLC); blood, muscle, liver and kidney tissues were analyzed for NFLX. The tissue distribution profile of NFLX in both species was found to be very similar. At the conclusion of the NFLX treatment, tissue concentrations decreased in the following order: kidney > liver > muscle ≈ whole blood. NFLX tissue concentrations in black sea bream were much higher than those of Japanese sea perch. Elimination half-lives of NFLX in the whole blood, muscle, liver and kidney in Japanese sea perch and black sea bream were 5.06, 3.96, 2.37, 1.82d and 4.03, 3.75, 5.33, 3.87d, respectively. The results show that NFLX concentrations in the muscle of Japanese sea perch and black sea bream fell below the 0.01 µg/g detection limit at day 14 and day 32 post-dosing. These results helped the Chinese fishery department establish a reasonable withdrawal period for NFLX in farmed Japanese sea perch and black sea bream. [Copyright &y& Elsevier]