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The interfacial adhesion between aggregate and asphalt is a critical factor affecting the water damage resistance performance of asphalt mixtures. To enhance the adhesion between aggregate and asphalt, Methyltrimethoxysilane (MPTMS) and Dimethyldimethoxysilane (DMDMOS) were co-opted to modify the aggregate surface. The interfacial strength between aggregate and asphalt was analyzed by water boiling test and contact angle experiment, and the mechanism of aggregate interfacial modification was investigated by combining SEM, FTIR and MD. The results showed that: hydrophobic treatment of aggregates reduces the water absorption rate of aggregates in a wet environment and significantly improves the water damage resistance of asphalt mixtures; MPTMS and DMDMOS reduced the aggregate surface polarity component, thus improving the match between aggregate and asphalt; The optimal processing environment for aggregates is acidity and 30 minutes. Further mechanistic tests and simulations showed that the reactive Si-O portion of the polymer reacts with the Si-O-C portion of MPTMS and DMDMOS to form hydrophobic clusters on the surface of the polymer, increasing the aggregate surface roughness. The clusters attract asphalt molecules to arrange closely and orderly around them. The intramolecular interactions and molecular angular energy of asphalt molecules are significantly reduced, which improves the stability of the aggregate-asphalt system, and further enhances the bonding energy between the aggregate and the asphalt, thus improving the water damage resistance of asphalt mixtures. • MPTMS and DMDMOS can improves the adhesion properties of asphalt mixtures. • An acidic environment and a 30-minute processing time are optimal. • MPTMS and DMDMOS react with aggregates to form Si-O-Si and produce fluffy protrusions. • The fluffy protrusions affects the arrangement of asphalt molecules. [ABSTRACT FROM AUTHOR]

The application of waste rubber powder (WRP) for asphalt pavement could achieve the harmless and resourceful utilization of solid waste, but the storage stability of waste rubber powder modified asphalt (RA) is one of the main problems restricting its application. Existing studies have demonstrated that graphene could enhance the storage stability of RA, but graphene's size effect on the modifying effect and its corresponding mechanism are still uncertain. In this research, the effects of graphene microstructural properties (i.e., molecular size and layer number) on the storage stability of RA were investigated by storage stability testing, dynamic shear rheometry (DSR) testing and fluorescence microscopy (FM) testing, in combination with molecular dynamics simulation (MD). The experimental results indicated that graphene improved the storage stability of RA significantly, with few-layer graphene being more effective in enhancing it. MD was used to investigate the graphene size effect on RA in compatibility, intermolecular binding energy and structural stability of the system. The simulation results revealed that small-sized graphene molecules were more compatible with RA. Meanwhile, few-layer, small-sized graphene can provide higher binding energy and better enhancement of storage stability of RA. The number of graphene layers mainly influences the binding energy rather than solubility parameters. The relative concentration distribution results demonstrated that graphene facilitated the spatial distribution of asphaltenes, rubber components and light components. This research provides theoretical support for the rational selection of microstructural properties of graphene to improve the modified asphalt storage stability performance. [ABSTRACT FROM AUTHOR]

• A matrix binder was modified to possess excellent low-temperature properties and anti-ultraviolet aging properties. • The response surface method was used to determine the dosage of modifies. • The interaction and modification mechanism of modifiers were revealed by FTIR and SEM. In order to improve the high-temperature performance and anti-ultraviolet aging performance of butadiene styrene rubber (SBR) modified asphalt, nano-TiO 2 and Montmorillonite (MMT) were used for composite modification, and the test scheme was determined by Box Behnken Design (BBD). The high-speed shearing method is used to prepare nano-TiO 2 /MMT/SBR composite modified asphalt. Meanwhile, the dynamic shear rheometer (DSR) test and the bending beam rheometer (BBR) test were used to evaluate the rheological properties of the composite modified asphalt before and after aging to evaluate its anti-ultraviolet aging performance. Finally, the interaction and modification mechanism of the modifiers were revealed by scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR). The results show that the optimal dosage of nano-TiO 2 , nano-MMT and SBR latex (solid content 60%) are 1.5%, 4%, and 6%, respectively. The synergistic effect of nano-TiO 2 and nano-MMT can significantly delay the conversion process of light components to asphaltenes during asphalt aging, and makes CMI value of SBR modified asphalt significantly reduced and almost stabilized at about 2, and the average stiffness modulus change rate decreases from 0.27 to 0.13, and the carbonyl index dropped from 5.16 to 0.28. SEM test results show that nano-TiO 2 particles can be used as physical cross-linking points to promote the combination of nano-MMT/SBR modifiers and asphalt, making the microstructure of nano-TiO 2 /MMT/SBR modified asphalt more stable and uniform. The modification of Nano-TiO 2 /MMT/SBR to asphalt is a physical modification process, more Si-O-Si functional groups were generated during the aging process of MMT, which further promote the formation of MMT and asphalt network structure. In conclusion, the study of nano-TiO 2 /MMT/SBR composite modified asphalt in this paper provided a reference for the selection of modified asphalt in cold and ultraviolet regions. [ABSTRACT FROM AUTHOR]

Forty-four microsatellite DNA markers were developed for silver carp, and used to investigate polymorphisms of 41 wild silver carps and seven wild bighead carps collected from Jingzhou fragment of Yangtze River. In silver carp, 40 markers were polymorphic. A total of 297 alleles were detected at 40 polymorphic loci. The number of alleles per locus varied from two to 16 with an average of 7.4 and the expected heterozygosities of each locus ranged from 0.07 to 0.91 with an average of 0.69. All markers amplified both silver carp and bighead carp DNAs. [ABSTRACT FROM AUTHOR]

Abstract: Complementary DNA (cDNA) sequences of Japanese seabass (Lateolabrax japonicus) and Japanese flounder (Paralichthys olivaceus) prion protein (PrP) encoding genes were cloned and characterized through RT-PCR approach. The PrPs of two fish species consist of 507 and 497 amino acid residues with an estimated molecular weight of about 54 and 52 kilodaltons, respectively. The deduced amino acid sequences of two sequences are about 65% similar to those of Japanese pufferfish (Fugu rubripes, stPrP-1) and Atlantic salmon (Salmo salar) in average, and bear the structural features of PrPs including a signal sequence, tandem repeats, a hydrophobic region, glycosylation sites, two cystein residues potentially involved in the formation of a disulphide bridge and a glycosyl phosphatidylinositol anchor site. The isolation of two PrP encoding genes will facilitate the exploration concerning the evolution, structure and function of PrPs and possible transmissible spongiform encephalopathies (TSE) in fish. [Copyright &y& Elsevier]

The previous studies have indicated that Photobacterium damselae subsp. damselae (Pdd) was the pathogen of black rockfish (Sebastes schlegeli) with seriously skin ulcer symptom. This study aimed to explore the spleen transcriptome response of S. schlegeli at 24 h (P24 group) and 48 h (P48 group) after Pdd infection and characterize expression profile of immune‐related genes. The fish in the control group were injected with equal volume of PBS. Results showed that there were 2,139 (88.42%), 510 (21.08%) and 242 (10%) differentially expressed genes in PBS vs P24, PBS vs P48 and P24 vs P48 respectively. As the time increases, the number of differential genes gradually decreases. GO annotation indicated that the immune‐related function category contributed the most in the PBS vs P24 and PBS vs P48 groups, including immune response, immune system process, immune effector process and regulation of immune system process. KEGG enrichment analysis showed that these genes were located on 277, 184 and 164 signalling pathways in the PBS vs P24, PBS vs P48 and P24 vs P48 groups respectively; among them, 30, 26 and 16 pathways were related to immune system, involving 344, 119 and 24 genes. P24 group involved more immune‐related signal pathways and genes than P48 group. RT‐qPCR validation indicated that the expression patterns of 10 genes at different time points were well agreed with RNA‐Seq analysis. This study provided a better understanding of the molecular responses to photobacteriosis in S. schlegeli. [ABSTRACT FROM AUTHOR]

• The improvement of the rheological properties of asphalt by graphene was studied. • Using multiple-scale experiments combined with molecular dynamics simulation. • The focus is on the size effect of graphene on the modification efficiency. The use of waste rubber powder modified asphalt (RA) in road engineering can lead to environmental and economic benefits. However, there are still some concerns over the performance of the pavement with RA, especially the rheological properties under heavy traffic conditions. This paper aims to investigate the improvement effects of graphene on the rheological properties of RA using multiple-scale experimental characterizations combined with molecular dynamics simulation. Special attention was paid to the influence of geometric characteristics of graphene on the modification efficiency. The experimental findings demonstrated that the physical blending of graphene and RA could enhance viscoelasticity, persistent deformation, and mobility resistance of modified asphalt, while its low-temperature performances were marginally improved with the graphene. Graphene with a single layer or a few layers was more efficient in enhancing the high-temperature deformation and rutting resistance and microstructures of RA than that with multiple layers. The molecular dynamics simulation results showed that graphene could improve the shear viscosity of the modified asphalt and inhibit the diffusion of asphalt components, and the effect on the low-temperature performance is related to the size effect. Moreover, the size of graphene particles could strongly influence the performances of the modified asphalt. Specifically, increasing the graphene size decreased the shear viscosity, free volume fraction, and glass transition temperature, indicating the improved deformation resistance. The change in the number of graphene layers was more effective in altering the modification effect of small-sized graphene compared to large-sized graphene. This research can offer a theoretical guideline for optimizing the use of graphene in modified asphalt. [ABSTRACT FROM AUTHOR]

Generally speaking, fish intestinal microbiota is easily affected by food or water environment, and it may be dynamically changed along with body growth. However, it remains unclear whether fish gut microbiota can be affected under any conditions. In the present study, we focused on cultured larval turbot (Scophthalmus maximus) and tracked its artificial breeding process from eggs to larvae in two farms located in different regions of China. Through continuous sampling, we analyzed and compared characteristics of intestinal microbiota in turbot larvae and its correlation with the bacteria in water and food at different developmental stages. The results showed that there was a steady group of microbiota in larval gut, and the highest relative abundance of strain was same between the two farms. This microbiota was established soon after hatching of fertilized eggs. Particularly, the structure of this microbiota was nearly not changeable afterward 3–4 months of development. The bacteria carried by fertilized eggs might play an important role during the formation of this microbiota. In conclusion, our findings suggested that there was a core microbiota represented by Lactococcus sp. in gut of artificially bred turbot larvae. The relative proportion of such strain in gut was higher than 30% at the initial stage of turbot life. [ABSTRACT FROM AUTHOR]

In this study, the influences of immersion bathing in different concentrations of Bacillus velezensis DY-6 on the body weight gain rate and non-specific immune enzyme activities of the coelom fluid of sea cucumber (Apostichopus japonicus) were determined in order to obtain the optimum bacterial concentration. The gut microbiota change in A. japonicus was then analyzed through high-throughput sequencing during the immersion bathing in B. velezensis DY-6 at the optimum concentration for 49 d. The results illustrate that the body weight growth rate of all bathing groups was higher than that of the control. The highest growth rate (25.3%) was achieved when the bacterial concentration was 1×103 CFU/mL. The activities of non-specific immune enzymes (ACP, AKP, SOD and LZM) of all bathing groups increased, and the activities of the enzymes of groups bathed with the bacterium at 1×103 and 1×104 CFU/mL reached the highest on day 21 and day 28. Taking the growth rate and economic cost into consideration, the optimum concentration of B. velezensis DY-6 was 1×103 CFU/mL. The influences of immersion bathing in B. velezensis DY-6 at 1×103 CFU/mL on the gut microbiota of A. japonicus were then evaluated through 16S rDNA sequencing analysis. Results showed that the gut microbiota changed with the addition of B. velezensis DY-6, and the richness and diversity of the gut microbiota peaked twice on day 14 and day 21, respectively. In association with the non-specific immune enzyme activities and if day 28 was selected as the dividing point, the community structure of the gut microbiota could be obviously divided into two types. The correlation analysis revealed that the non-specific immune enzyme activities were correlated significantly to some gut bacteria (in the phyla Firmicutes, Proteobacteria, and Bacteroidetes) after immersion bathing in B. velezensis DY-6. Our findings will provide the theoretical foundation for probiotic application in sea cucumber farming. [ABSTRACT FROM AUTHOR]

Various bacteria that adhere to the gut are important for the health of fish. Regulating the microbial community in a desirable direction may be beneficial in aquaculture for preventing and controlling the diseases caused by pathogenic microbes. In this study, we investigated the changes in the microflora in the intestinal tracts of turbot (Scophthalmus maximus) larvae after introducing a probiotic (Bacillus amyloliquefaciens) after the first feed. B. amyloliquefaciens was added as part of a nutrient enrichment system in live feed (Branchionus plicatilis or Artemia sinica), so it passed into the intestinal tracts of the newly hatched turbot larvae. The turbot larvae were fed on live feed containing B. amyloliquefaciens in the experimental group, whereas live feed without the probiotic was provided to larvae in the control group. The total bacterial genomic DNA in the larval guts was extracted and sequenced with an Illumina HiSeq PE250 system. According to the sequencing results, the abundances of microbial species and the microflora diversity were lower in the intestines in the experimental group than the control. Throughout development, the microflora structure in the intestines was mainly constructed before the first feed and the composition of the dominant operational taxonomic units (OTUs) was stable, where the abundances of OTU8, OTU124, OTU150, OTU107, and OTU17 were always high. Compared with the control, the structures of the microflora in the intestines were similar on different days during the development and the growth of larvae in the experimental group. However, the similarity of the microflora structure between different treatments was low on the same day. Furthermore, the mean proportion of common OTUs was only 74.7% in different treatments on each day, which indicates that the introduction of B. amyloliquefaciens in the live feed changed the microflora structure in the intestine. During the early development stage (days 3–30), the average abundance of Pseudomonas was reduced by 0.8% whereas that of Lactococcus increased by 3.5% in the experimental group. Pseudomonas spp. are considered potentially pathogenic bacteria but there is no direct evidence for the pathogenicity of Lactococcus in turbot. Moreover, several Lactococcus species are regarded as probiotics in aquaculture. Therefore, the use of B. amyloliquefaciens could be beneficial for optimizing the microbial community structure in the intestines of turbot larvae, which may explain the probiotic effect of B. amyloliquefaciens. This study provides a theoretical basis for the biological regulation of the microflora structure in the intestinal tract during turbot breeding. [ABSTRACT FROM AUTHOR]

Photobacterium damselae subsp. damselae (PDD) is a Gram-negative bacterium that can infect a variety of aquatic organisms and humans. Based on an epidemiological investigation conducted over the past 3 years, PDD is one of the most important pathogens causing septic skin ulcer in deep-sea cage-cultured Sebastes schlegelii in the Huang-Bohai Sea area and present throughout the year with high abundance. To further understand the pathogenicity of this species, the pathogenic properties and genome of PDD strain SSPD1601 were analyzed. The results revealed that PDD strain SSPD1601 is a rod-shaped cell with a single polar flagellum, and the clinical symptoms were replicated during artificial infection. The SSPD1601 genome consists of two chromosomes and two plasmids, totaling 4,252,294 bp with 3,751 coding sequences (CDSs), 196 tRNA genes, and 47 rRNA genes. Common virulence factors including flagellin, Fur, RstB, hcpA, OMPs, htpB-Hsp60, VasK, and vgrG were found in strain SSPD1601. Furthermore, SSPD1601 is a pPHDD1-negative strain containing the hemolysin gene hlyAch and three putative hemolysins (emrA, yoaF, and VPA0226), which are likely responsible for the pathogenicity of SSPD1601. The phylogenetic analysis revealed SSPD1601 to be most closely related to Phdp Wu-1. In addition, the antibiotic resistance phenotype indicated that SSPD1601 was not sensitive to ceftazidime, pipemidic, streptomycin, cefalexin, bacitracin, cefoperazone sodium, acetylspiramycin, clarithromycin, amikacin, gentamycin, kanamycin, oxacillin, ampicillin, and trimethoprim-sulfamethoxazole, but only the bacitracin resistance gene bacA was detected based on Antibiotic Resistance Genes Database. These results expand our understanding of PDD, setting the stage for further studies of its pathogenesis and disease prevention. [ABSTRACT FROM AUTHOR]

The effects of an exogenous probiotic (Bacillus amyloliquefaciens) on microbial community structure of Branchionus plicatils and Artemia sinica were evaluated in this study during turbot (Scophthalmus maximus) larval breeding. The analysis and comparison of the microfloral composition of live feed with probiotic was conducted using the Illumina HiSeq PE250. The abundance of microbial species and diversity of microflora in live feed with B. amyloliquefaciens were higher than those in the control. The microfloral composition was similar among the three replicate experimental groups of B. plicatils compared with the control after enrichment. Lactococcus, Pseudoalteromonas, and Alteromonas were always dominant. Additionally, some other bacterial species became dominant during the enrichment process. The microbial community during nutrient enrichment of A. sinica was rather similar among the three control replicates. Relative abundance of Cobetia sp., the most dominant species, was 54%–65.2%. Similarity in the microbial community was still high after adding B. amyloliquefaciens. Furthermore, Pseudoalteromonas and Alteromonas replaced Cobetia as the dominant species, and the abundance of Cobetia decreased to 4.3%–25.3%. Mean common ratios at the operational taxonomic unit level were 50%–60% between the two B. plicatils and A. sinica treatments. Therefore, the microbial community structure changed after adding B. amyloliquefaciens during nutrient enrichment of B. plicatils or A. sinica and tended to stabilize. Additionally, the abundance of Vibrio in any kind of live feed was not significantly different from that in the control. These results will help improve the microflora of B. plicatils and A. sinica and can be used to understand the multiple-level transfer role of probiotic species among probiotic products, microflora of live feed, and fish larvae. [ABSTRACT FROM AUTHOR]

[Display omitted] • The strong polar plasticizers have poor inter-solubility with the saturates and good inter-solubility with the other three components of asphalt. • The ranking of the compatibility between plasticizers and asphalt obtained by simulation and experiment, from best to worst, is trioctyl trimellitate, dioctyl adipate, dioctyl phthalate, and acetyl tributyl citrate. • Molecular polarity and spatial configuration are important factors affecting the binding stability of plasticizers and asphalt's four components. • The selection of plasticizer schould be based on the proportion of the four components in asphalt during engineering applications. This work aims to reveal the compatibility mechanism of different plasticizers with the base asphalt using molecular dynamics (MD) simulation. For this purpose, four kinds of plasticizers were chosen, namely dioctyl phthalate (DOP), dioctyl adipate (DOA), acetyl tributyl citrate (ATBC), and trioctyl trimellitate (TOTM). The compatibility between those plasticizers and the asphalt was evaluated by various MD simulation parameters, including electric dipole moment, solubility parameters, and binding energy, and the simulation results were verified using macroscopic tests. The results show that the four plasticizers are effectively miscible with asphalt within the temperature range of 130 °C to 170 °C. The optimal temperatures for DOP, DOA, ATBC, and TOTM in modified asphalt preparation are 140 °C, 130 °C, 140 °C, and 150 °C respectively. The saturate component is more miscible with weak polar plasticizers, while the other three asphalt components are more miscible with strong polar plasticizers. TOTM has the best stability in combination with asphalt and ATBC has the worst. Aromatics and saturates have better torsional and bending deformation ability, and are more likely to form stable blending systems with strong polar plasticizers. Asphaltenes and resins have more stable benzene ring structures, they have greater binding energy with DOA, which is chain-variable and weakly polarized. [ABSTRACT FROM AUTHOR]

Abstract: Genetic linkage maps of guppy (Poecilia reticulata) were constructed using microsatellite DNA and AFLP markers and a pseudo-testcross mapping strategy. (AC)n microsatellite DNA markers were developed and used to genotype sixty-one full-sib progenies (F1) and their two parents. Of 293 microsatellite DNA markers, 101 segregated at 1:1 or 1:1:1:1 ratios. In addition, 336 AFLP markers segregated also in F1 progenies at 1:1 ratio, which were produced using 91 primer combinations. All these markers were mapped with two linkage maps produced, one each parent. Female map included 135 markers in 22 linkage groups, covering a total of 1267.7 cM in length. Male map included 172 markers in 20 linkage groups, covering a total of 1771.2 cM in length. [Copyright &y& Elsevier]