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Abstract A series of smart shape memory poly(ɛ-caprolactones) (PCL)/hydroxyapatite (HA) networks with different PCL arm lengths are designed and fabricated by the thiol-ene click reaction of thiol-modified HA particles with functional acrylate-terminated PCL. Compared with traditional physical blending of nanoparticles into polymer, this paper constructs a well-defined network architecture on the basis of the molecular level. Thermal and crystalline results indicate that the shape memory transition temperature (T trans) of the composites is correlated to the initial PCL diol molecular weight, the melting and crystallization temperature of the networks gradually increase with increasing PCL diol molecular weight. Meanwhile, the HA-PCL networks all exhibit good shape memory capability under thermal stimulus with good shape fixing ratio and recovery ratio irrespective of the molecular weight of PCL diol. An advantage of these network is that the intrinsic biocompatibility of HA nanoparticles as a netpoint for biodegradable PCL renders it a good prospects in the bone biomedical applications. Graphical abstract A new synthetic method to obtain shape memory poly(ε-caprolactone) (PCL) cross-linked by HAp via photo-initiated thiol-ene reaction is described. Compared with traditional physical blending of HA nanoparticles into polymer, this paper constructs a well-defined network architecture on the basis of the molecular level and all network exhibit desirable shape memory properties. The melting transition temperature of HA-PCL network is tuned by varying the molecular weight of the acrylate-terminated PCL. fx1 Highlights • This paper presents a novel shape memory poly(ɛ-caprolactones) (PCL)/hydroxyapatite (HA) networks via photo-initiated thiol-ene click reaction. • Compared with traditional physical blending of nanoparticles into polymer, our work constructs a well-defined network architecture on the basis of the molecular level. • Thiol-ene network features a uniform distribution of PCL chains with desirable shape memory properties. • The melting transition temperature is tuned by varying the molecular weight of the acrylate-terminated PCL. [ABSTRACT FROM AUTHOR]

Myxovirus resistance (Mx) proteins are interferon (IFN)-inducible Dynamin-like GTPases, which play an important role in antiviral immunity. Three Mx genes (Mx1-3) have been cloned previously in rainbow trout. In this study, an additional six Mx genes were cloned that reside in four chromosomal loci. Further bioinformatics analysis suggests the presence of three teleost Mx groups (TMG) each with a characteristic gene organisation. Salmonid Mx belong to TMG1 and TMG2. The increased salmonid Mx gene copies are due mainly to local gene duplications that happened before and after salmonid speciation, in a lineage/species specific manner. Trout Mx molecules have been diversified in the loop 1 and 4 regions, and in the nuclear localisation signal in loop 4. The trout Mx genes were shown to be differentially expressed in tissues, with high levels of expression of TMG1 (Mx1-4) in blood and TMG2 (Mx5-9) in intestine. The expression of the majority of the trout Mx genes was induced by poly IC in vitro and in vivo , and increased during development. In addition, induction by antiviral (IFN) and proinflammatory cytokines was studied, and showed that type I IFN, IFNγ and IL-1β can induce Mx gene expression in an Mx gene-, cytokine- and cell line-dependent manner. These results show that salmonids possess a large number Mx genes as well as complex regulatory pathways, which may contribute to their success in an anadromous life style. • In addition to Mx1-3, six novel Mx genes (Mx4-9) have been cloned in rainbow trout. • Salmonids possesses 4 groups of Mx genes residing at four chromosome loci. • Trout Mx1-4 are highly expressed in blood but Mx5-9 are highly expressed in intestine. • Trout Mx gene expression can be induced by poly IC, type I and type II IFNs, and IL-1β. • The potency of IFN induced Mx expression is gene- and cell line-dependent. [ABSTRACT FROM AUTHOR]

Abstract Dabry's sturgeon (Acipenser dabryanus), as a living fossil, is considered a critically endangered aquatic animal in China. To date, the immune system of this species remains largely unknown, with limited available sequence information. In addition, increasing incidence of bacterial pathogenic diseases has been reported. Hence, the present study aimed to characterize comprehensively transcriptome profile of the head kidney from Dabry's sturgeon infected with Aeromonas hydrophila using Illumina platform. Over 42 million high-quality reads were obtained and de novo assembled into a final set of 195240 unique transcript fragments (unigenes), with an average length of 564 bp. Approximately 41702 unigenes were annotated in the NR NCBI database. Dabry's sturgeon unigenes had the highest number of hits with 14365 (34.45%) to Lepisosteus oculatus. The 195240 unigenes were assigned to three Gene Ontology (GO) categories: biological process, cellular component, and molecular function. Among them, 27770 unigenes were clustered into 26 Eukaryotic Orthologous Group (KOG) functional categories, and 36031 unigenes were mapped to 335 known Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. After A. hydrophila administration, 1728 differentially expressed unigenes were identified, including 980 upregulated and 748 downregulated unigenes. Further KEGG enrichment analysis of these unigenes identified 16 immune-related pathways, including the Toll-like receptor signaling pathway, chemokine signaling pathway, complement and coagulation pathway, RIG-I-like receptor signaling pathway, and NOD-like receptor signaling pathway. 20 DEGs were selected and their expression patterns are largely consistent with the transcriptome profile analysis, which clearly validated the reliability of the DEGs in transcriptome analysis. This work revealed novel gene expression patterns of Dabry's sturgeon host defense and contributes to a better understanding of the immune system and defense mechanisms of Dabry's sturgeon in response to bacterial infection. The results provide valuable references for studies in sturgeons that lack complete genomic sequences, and could also be helpful for the analyzing evolution among cartilaginous and teleost fish. Highlights • The head kidneys transcriptome of Dabry's sturgeon were constructed using Illumina XTen platform. • Totally, 195240 unigenes were obtained from the transcriptome. • Toll-like signaling pathway, Chemokine signaling pathway, RIG-I-like and NOD-like receptor signaling pathways were analyzed. • A total of 1728 differentially expressed unigenes were identified, including 980 upregulated and 748 downregulated unigenes. [ABSTRACT FROM AUTHOR]

Colloidal phosphorus (P) is an important P form in agricultural runoff and can threaten water quality. However, up to date, there are few effective approaches to mitigate colloidal P pollution. This study investigated the effect of ultraviolet (UV) irradiation on medium-colloidal (MC; 220 nm–450 nm) and fine-colloidal (FC; 3 kDa–220 nm) P in agricultural runoff. Under 24 h of UV irradiation, as the most abundant colloidal P fraction, concentration of total P (TP) in FC consistently decreased by 81.0%, while TP concentration in MC first increased by 74.4% after 3 h and then decreased with irradiation time. At the same time, particulate TP (>450 nm) concentration was found to be increased from 0 to 14.7 μM. However, there were no obvious variations in TP concentrations in FC and MC fractions under dark conditions. In FC fraction, with the decrease of TP, the corresponding concentrations of iron (Fe), aluminum (Al), silicon (Si) declined synchronously, and ferric iron/ferrous iron (Fe(III)/Fe(II)) ratio and organic matter (OM) concentration were reduced as well. These results suggested that P in FC fraction was gradually transformed into particulate P during photoreduction of Fe(III) and photodegradation of OM under UV irradiation. Our study helps to understand the mechanism of the phototransformation of colloidal P, and propose an UV irradiation-based approach to remove colloidal P in agricultural runoff. [Display omitted] • Colloidal P in agricultural runoff was UV-sensitive. • Fine-colloidal P was transformed into particulate P under UV irradiation. • Fine-colloidal P was photoremoved during phototransformation of OM and Fe(III). [ABSTRACT FROM AUTHOR]

Abstract The reuse of water in agriculture has become more common in water management worldwide. However, there is very limited information about nutrient retention in water reclamation management. In this study, an improved low impact development (LID) practice was constructed to investigate the synergistic effects of three substrates amendment on nitrogen (N) and phosphorus (P) retention under two irrigation modules: spray and drip irrigation. The orthogonal combination of the three substrates was controlled during four leaching events, with polyacrylamide (PAM), peat soil, and straw biochar application rates of 1, 2, and 4 g kg−1; 5, 10, and 20 g kg−1; and 10, 20, and 40 g kg−1, respectively. Results showed that the optimum treatments for N and P were 2 g kg−1 of PAM; 2 g kg−1 of PAM, 10 g kg−1 of peat soil, and 40 g kg−1 of straw biochar, respectively. The highest amounts of N and P retention under spray and drip irrigation were 83.12 mg N kg−1 and 50.09 mg N·kg−1, and 11.88 mg P·kg−1 and 7.47 mg P·kg−1, respectively. The analysis of variance indicated that PAM, biochar, and peat soil affected the retention of leachate, N, and P differently. PAM application could not only improve the water, N, P retention capacity of soil, but also significantly increase the content of ＞2 mm water-stable soil aggregate (WSA) (p ＜0.05), and there is an advisable linear relation between N, P retention and the content of ＞2 mm WSA (R 2 = 0.79, 0.67, respectively). Overall, this study concludes that a combined application of PAM and biochar could reduce P loss and increase the ＞2 mm WSA under leaching condition. Highlights • An improved low impact development system packed with different substrates can retain leachate nitrogen and phosphorus. • PAM application rate at 2 g·kg−1 of soil achieved the maximum amount of nitrogen and phosphorus retention from LID systems. • PAM combined with biochar can reduce phosphorus loss and enhance the water retention capacity of soil from LID systems. [ABSTRACT FROM AUTHOR]

Abstract As a typical non-uniform beam with complex varying cross-section and large curvature, free vibration analysis of flexure hinges in the state-of-the-art compliant mechanisms is challenging due to their complicated and even unsolvable governing differential equation. Investigation on the free vibration analysis of non-uniform beams was attractive in the past but still with a few types of specific beams or approximate solutions. The contribution of this paper is to formulate the dynamic stiffness matrix for generic non-uniform beams and applied for the first time to the free vibration analysis of flexure hinges. Firstly, the vibration solution of general non-uniform Timoshenko beam is derived by using a recursive integral in power series of circular frequency but not the traditional way in the well-known method of Frobenious. Then, the dynamic stiffness matrix of non-uniform Timoshenko beam is derived based on the variational principle. At last, the new method is applied for the free vibration analysis of flexure hinges and flexure-based compliant mechanisms. Several case studies demonstrate the advantage of the proposed approach in terms of high accuracy, generality and high efficiency (only one element is needed). The obtained results are useful for dynamic design of flexure hinges and can serve as a benchmark to examine the accuracy of other numerical solutions. Due to the closed form and universality of the proposed method, it is also of benefit for free vibration analysis of other non-uniform beams with all kinds of varying cross-section or functionally graded beams. [ABSTRACT FROM AUTHOR]

Tripartite motif (TRIM) proteins are receiving increased research interest because of their roles in a wide range of cellular biological processes in innate immunity. In zebrafish ( Danio rerio ), the functions of the finTRIM ( ftr ) family are unclear. In the present study, we investigated the expression pattern of ftr12 , ftr51 , ftr67 , ftr82 , ftr83 , and ftr84 in zebrafish for the first time. The results showed that ftr12 , ftr67 , and ftr84 are maternally expressed in the oocyte and highly expressed at the early stage (0–4 hpf) of embryo ( P < 0.05), suggesting their involvement in the embryonic innate defense system. The ftr82 gene was highly expressed at 8 hpf ( P < 0.05), which implied that the embryos could synthesize their own immunity-related mRNAs. However, ftr51 and ftr83 were highest at 8 hpf (2.33 and 51.53 relative to β-actin respectively) and might mediate embryonic development. The expression levels of ftr12 , ftr51 , and ftr67 were highest in the gill, intestines, and liver, respectively. Ftr82 , ftr83 , and ftr84 were predominantly expressed in the kidney, suggesting that these finTRIMs might play roles in both immunity and non-immunity-related tissue compartments. Zebrafish embryonic fibroblast (ZF4) cells were infected with Grass carp reovirus (GCRV) and Spring viremia of carp virus (SVCV). During GCRV infection, the expression of ftr12 was significantly upregulated from 12 h to 24 h; and ftr51 and ftr67 increased from 3 h to 12 h. The expressions of ftr82, ftr83, and ftr84 were only upregulated at 12 h, 12 h, and 24 h, respectively. All of these genes were significantly downregulated at 48 h ( P < 0.05). Challenge with SVCV upregulated the expressions of ftr12 and ftr51 at 12 h and 48 h ( P < 0.05), respectively, and ftr67 reached its highest expression level at 3 h. ftr82 showed only a slight upregulation at 6 h and 48 h, and ftr83 and ftr84 were consecutively increased, reaching their highest levels at 12 h ( P < 0.05). Meanwhile, ftr67 and ftr83 were significantly downregulated at 48 h ( P < 0.05). Our research demonstrated that ftr12 , ftr51 , ftr67 , ftr82 , ftr83 , and ftr84 probably have important roles in innate immune responses and in non-immunity-related tissues. [ABSTRACT FROM AUTHOR]

In mammals, interferon regulatory factor 4 (IRF4) plays an important role in the process of development and differentiation of B cells, T cells and dendritic cells. It can regulate immune pathway through IRF5, MyD88, IL21, PGC1α, and NOD2. In the present study, we investigated the expression pattern of IRF4 paralogues and these related genes for the first time in teleosts. The results showed that these genes were all expressed predominantly in known immune tissues while IRF5 was also relatively highly expressed in muscle. IRF4b, IL21, MyD88, IRF5 and NOD2 showed maternal expression in the oocyte and the higher expression of IRF4a, Mx and PGC1α before hatching might be involved in the embryonic innate defense system. Zebrafish embryonic fibroblast (ZF4) cells were infected with GCRV and SVCV. During GCRV infection, the expression of Mx was significantly up-regulated from 3 h to 24 h, reaching the highest level at 12 h (101.5-fold over the controls, P < 0.001). And the expression of IRF4a was significantly up-regulated from 3 h to 48 h, reaching the highest level at 12 h (13.75-fold over the controls, P < 0.001). While the expression of IRF4b was only slightly up-regulated at 12 h and 24 h (3.39-fold, 1.93-fold) above control levels, respectively. Whereas the expression of Mx was significantly up-regulated during SVCV infection from 1 h to 48 h, reaching the highest level at 24 h (11.49-fold over the controls, P < 0.001). IRF4a transcripts were significantly up-regulated from 6 h to 24 h, reaching the highest level at 24 h (41-fold over the controls, P < 0.01). IRF4b only showed a slightly up-regulation by SVCV at 24 h (3.2-fold over the controls, P < 0.01). IRF4a and IRF4b displayed a distinct tissue expression pattern, embryonic stages expression and inducible expression in vivo and in vitro, suggesting that IRF4 paralogues might play different roles in immune system. [ABSTRACT FROM AUTHOR]

Lakes are important methane (CH 4) sources to the atmosphere, especially eutrophic lakes with cyanobacterial blooms accompanied by volatile sulfur compound (VSC) emissions. CH 4 oxidation is a key strategy to mitigate CH 4 emission from lakes. In this study, we characterized the fate of CH 4 -derived carbon and active microbial communities in lake sediments with CS 2 used as a typical VSC, based on the investigation of CH 4 and VSC fluxes from Meiliang Bay in Lake Taihu. Stable isotope probing microcosm incubation showed that the efficiency of CH 4 -derived carbon incorporated into organic matter was 21.1% in the sediment with CS 2 existence, which was lower than that without CS 2 (27.3%). SO 4 2--S was the main product of CS 2 oxidation under aerobic condition, accounting for 59.3–62.7% of the input CS 2 –S. CS 2 and CH 4 coexistence led to a decrease of methanotroph and methylotroph abundances and stimulated the production of extracellular polymeric substances. CS 2 and its metabolites including total sulfur, SO 4 2− and acid volatile sulfur acted as the main drivers influencing the active microbial community structure in the sediments. Compared with α- proteobacteria methanotrophs , γ- proteobacteria methanotrophs Methylomicrobium, Methylomonas, Crenothrix and Methylosarcina were more dominant in the sediments. CH 4 -derived carbon mainly flowed into methylotrophs in the first stage. With CH 4 consumption, more CH 4 -derived carbon flowed into non-methylotrophs. CS 2 could prompt more CH 4 -derived carbon flowing into non-methanotrophs and non-methylotrophs, such as sulfur-metabolizing bacteria. These findings can help elucidate the influence of VSCs on microorganisms and provide insights to carbon fluxes from eutrophic lake systems. • H 2 S emissions have a strong linear correlation with CH 4 fluxes from Meiliang Bay. • H 2 S and CS 2 were the two detected VSC fluxes from Meiliang Bay. • CS 2 can increase sediment CE CO2-C and decrease sediment CCE. • SO 4 2 - -S is the main product of CS 2 oxidation under aerobic condition. • CS 2 prompts CH 4 -derived carbon flowing into nonmethylotrophs [ABSTRACT FROM AUTHOR]

The hyperaccumulating mechanism concerning heavy metal activation or passivation and plant response triggered by fulvic acid (FA) and humic acid (HA) recruitments are investigated herein. We carefully examine the Cd activation effect by various FA and HA, tracing from pig, goat, and duck manure composts to straw compost and commercial materials (i.e., PC, GC, DC, SC, and CM), as well as their roles in plant growth promotion and Cd uptake. Our results indicate that due to the decrease of soil pH and their multiple functional groups, the contents of available Cd (AE–Cd) increased by 4.3–4.8% and 3.6–6.3% when all FA and HA sources were applied for 30 days. A 13.1–19.9% increase in AE–Cd was observed when CFA, DFA, and PFA were applied for five days, and a 9.5% increment was found when PHA was applied for 10 days. In the pot experiment, the Cd accumulation in plants increased by 2.78 and 2.17 folds with PFA and PHA applications, respectively, compared to the blank control group. This result can be attributed to the stimulative effects of the simultaneous Sedum alfredii growth and Cd phytoavailability. Notably, the Cd accumulation increased by 2.26 times with the SFA amendment due to the predominant stimulation effect to the phytoavailable Cd rather than plant growth. However, slight inhibitory effects were observed upon plant growth or Cd uptake, which led to the reduction of the Cd accumulation with DHA, SHA, and CHA employments. Consistently, the corresponding soil Cd removal efficiencies were 43.5% and 34.6% with PFA and PHA, respectively, which hold abundant O- and N-containing groups. Our research aims to gain insights into the ternary interaction in the presence of heavy metal, humic substances, and S. alfredii to simultaneously accelerate Cd activation and hyperaccumulation. • FA and HA activated rather than passivated soil Cd indeed. • Cd-hyperaccumulation was enhanced by PFA and PHA with plentiful O-containing and N-containing groups. • A considerable phytoavailable Cd not plant growth was accelerated with SFA. • Indistinct effects contributed to a reduction of Cd accumulation with DHA, SHA and CHA. • The soil Cd removal efficient reached 43.5% and 34.6% with PFA and PHA, respectively. [ABSTRACT FROM AUTHOR]