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The present study was conducted to evaluate the hormesis and toxicity of shortterm low-dose aflatoxin B1 in grass carp (Ctenopharyngodon idellus). Triplicate isonitrogenous and isocaloric aflatoxin B1 diets—CD (control, 0 ug/kg), D1 (20 ug/kg), and D2 (500 ug/kg)—were prepared and fed to grass carp with an initial mean body weight of (15.2 ± 0.1) g for 56 days. The results showed that the weight gain rate and specific growth rate of grass carp fed diet D2 were significantly higher, and the feed coefficient and crude fat content of the whole body were significantly lower (P < 0.05) compared with those fed diet CD. Serum superoxide dismutase content of grass carp fed D1 diet increased significantly (P < 0.05) with an increasing dose of aflatoxin B1, but when the dose reached 500 ug/kg (D2), serum superoxide dismutase, complement C3, and immunoglobulin M of grass carp decreased significantly (P < 0.05), while malondialdehyde increased significantly (P < 0.05). After short-term feeding of aflatoxin B1-containing diets (D1 and D2), liver body index, visceral body index, serum total cholesterol, triglyceride, and urea nitrogen content of grass carp increased significantly (P < 0.05), total bile acid secretion decreased significantly (P < 0.05), and structural damages such as increase in vacuoles, organizational structure loosening, and nucleus translocation were observed in the liver. Meanwhile, liver function indexes such as serum alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase increased significantly with the increase of aflatoxin B1 dose (P < 0.05). In addition, the height of intestinal villi, crypt depth, villus–crypt ratio, and tubular cell number, as well as the content of trypsin and lipase activities in the intestine of grass carp in the D2 group, were significantly higher than those in the CD group (P < 0.05). In conclusion, after a short-term intake of low doses of aflatoxin B1 (≤500 ug/kg), the toxicological damage of aflatoxin B1 was pronounced, although it produced a certain degree of hormesis on the growth performance and intestinal structure and function of grass carp. At a dose of 20 ug/kg, the non-specific immune system and liver structure and function of grass carp showed obvious toxic damage. [ABSTRACT FROM AUTHOR]

Background. The WRKY transcription factor family plays crucial roles in many aspects of physiological processes and adaption to environment. Although the WRKY genes have been widely identified in various plant species, the structure and function of the WRKY family in sugar beet (Beta vulgaris L.) remains unknown. Methods. In the present study, the WRKY genes were identified from the sugar beet genome by bioinformatics. A phylogenetic tree was constructed by MEGA7.0. A distribution map of these genes was displayed by MapInspect 1.0. Furthermore, the exon-intron structure and the conserved motifs were predicted by GSDS 2.0 andMEME 5.0.5, respectively. Additionally, the expression levels of nine selected genes in shoots and roots of sugar beet seedlings exposed to alkaline stress were assayed by qRT-PCR. Results. A total of 58 putative BvWRKY genes are identified in the sugar beet genome. The coding sequences of these genes ranged from 558 to 2,307 bp and molecular weights (MWs) varied from 21.3 to 84. The BvWRKY genes are clustered into three major groups I, II, and III, with 11, 40, and seven members, based on the primary amino acid sequences. The number of introns in the BvWRKY genes ranged from 1 to 5, with a majority of BvWRKY (27/58) containing three exons. All the BvWRKY genes have one or two conserved WRKY domains and zinc-finger structure. Moreover, the selected BvWRKY genes showed a variety of expression patterns in shoots and roots of seedlings under various concentrations of NaHCO3. Importantly, BvWRKY10 in shoots and BvWRKY16 in roots were remarkably up-regulated by alkaline stress. Taken together, our findings extend understandings of the BvWRKY genes family and provide useful information for subsequent research on their functions in sugar beet under alkaline stress. [ABSTRACT FROM AUTHOR]

Pancreatic cancer (PC) is an aggressive and devastating disease with a poor prognosis. Cisplatin, a commonly used chemotherapeutic agent for solid tumors, is effective as a single agent or in combination with other drugs for the treatment of PC. Previous studies have suggested that Twist and growth differentiation factor 15 (GDF15) are involved in the progression of PC. However, the role of Twist and GDF15 in PC remains to be elucidated. In the present study, the individual effect of and interaction between Twist and GDF15 in PC cell invasion and chemoresistance to cisplatin was examined. Twist and/or GDF15 were stably overexpressed or knocked down in ASPC-1 and BXPC-3 human PC cells. Overexpression of Twist in the two cell lines markedly increased GDF15 expression, cell invasion, matrix metalloproteinase-2 expression/activity and the half maximal inhibitory concentration (IC50) values of cisplatin, which was eradicated by GDF15 knockdown or the selective p38 mitogen-activated protein kinase (MAPK) inhibitor SB203580 (10 μM). By contrast, Twist knockdown significantly decreased GDF15 expression, cell invasion, matrix metalloproteinase-2 expression/ activity and the IC50 values of cisplatin, which was completely reversed by overexpression of GDF15. In addition, while overexpression and knockdown of Twist increased and decreased p38 MAPK activity, respectively, GDF15 demonstrated no significant effect on p38 MAPK activity in PC cells. In conclusion, the present study, for the first time, to the best of our knowledge, demonstrated that Twist promotes PC cell invasion and cisplatin chemoresistance through inducing GDF15 expression via a p38 MAPK-dependent mechanism. The present study provides new insights into the molecular mechanisms underlying PC progression and chemoresistance. [ABSTRACT FROM AUTHOR]

Background: Gossypium raimondii is a Verticillium wilt-resistant cotton species whose genome encodes numerous disease resistance genes that play important roles in the defence against pathogens. However, the characteristics of resistance gene analogues (RGAs) and Verticillium dahliae response loci (VdRLs) have not been investigated on a global scale. In this study, the characteristics of RGA genes were systematically analysed using bioinformatics-driven methods. Moreover, the potential VdRLs involved in the defence response to Verticillium wilt were identified by RNA-seq and correlations with known resistance QTLs. Results: The G. raimondii genome encodes 1004 RGA genes, and most of these genes cluster in homology groups based on high levels of similarity. Interestingly, nearly half of the RGA genes occurred in 26 RGA-gene-rich clusters (Rgrcs). The homology analysis showed that sequence exchanges and tandem duplications frequently occurred within Rgrcs, and segmental duplications took place among the different Rgrcs. An RNA-seq analysis showed that the RGA genes play roles in cotton defence responses, forming 26 VdRLs inside in the Rgrcs after being inoculated with V. dahliae. A correlation analysis found that 12 VdRLs were adjacent to the known Verticillium wilt resistance QTLs, and that 5 were rich in NB-ARC domain-containing disease resistance genes. Conclusions: The cotton genome contains numerous RGA genes, and nearly half of them are located in clusters, which evolved by sequence exchanges, tandem duplications and segmental duplications. In the Rgrcs, 26 loci were induced by the V. dahliae inoculation, and 12 are in the vicinity of known Verticillium wilt resistance QTLs. [ABSTRACT FROM AUTHOR]

Background: Gossypium raimondii is a Verticillium wilt-resistant cotton species whose genome encodes numerous disease resistance genes that play important roles in the defence against pathogens. However, the characteristics of resistance gene analogues (RGAs) and Verticillium dahliae response loci (VdRLs) have not been investigated on a global scale. In this study, the characteristics of RGA genes were systematically analysed using bioinformatics-driven methods. Moreover, the potential VdRLs involved in the defence response to Verticillium wilt were identified by RNA-seq and correlations with known resistance QTLs. Results: The G. raimondii genome encodes 1004 RGA genes, and most of these genes cluster in homology groups based on high levels of similarity. Interestingly, nearly half of the RGA genes occurred in 26 RGA-gene-rich clusters (Rgrcs). The homology analysis showed that sequence exchanges and tandem duplications frequently occurred within Rgrcs, and segmental duplications took place among the different Rgrcs. An RNA-seq analysis showed that the RGA genes play roles in cotton defence responses, forming 26 VdRLs inside in the Rgrcs after being inoculated with V. dahliae. A correlation analysis found that 12 VdRLs were adjacent to the known Verticillium wilt resistance QTLs, and that 5 were rich in NB-ARC domain-containing disease resistance genes. Conclusions: The cotton genome contains numerous RGA genes, and nearly half of them are located in clusters, which evolved by sequence exchanges, tandem duplications and segmental duplications. In the Rgrcs, 26 loci were induced by the V. dahliae inoculation, and 12 are in the vicinity of known Verticillium wilt resistance QTLs. [ABSTRACT FROM AUTHOR]

In mobile ad hoc networks, mobile nodes have to communicate to each other without any infrastructure or base station. Thus, a lot of critical routing decision factors should be taken into considerations, such as reputation, reliability, availability, security, and mobility. Specially, the misconduct nodes due to unreliability, malfunction, migration, or malice may result in the loss and delay of packets. This paper proposes a fuzzy-based routing scheme based on reputation, bandwidth, and distance to overcome the misconduct mobile nodes and to enhance the performance of throughput. The scheme utilizes the ad hoc on-demand distance vector, the exponential smoothing model, and the fuzzy multiple-criteria group decision-making method to perform the routing path decision. Finally, the simulation is used to illustrate the performance of proposed scheme and existing methods. From the simulation results, the proposed scheme has better throughput than other schemes. [ABSTRACT FROM AUTHOR]

Background: Hepatitis B virus (HBV) infection causes large amount of unfolding or false-folding protein accumulation in the endoplasmic reticulum (ER), which in turn induces the expression of glucose-regulated protein 78 (GRP78). The aim in the present study was to analyse the potential association between GRP78 single-nucleotide polymorphisms (SNPs) and the risk of HBV infection. Methods: The associations between seven common GRP78 polymorphisms in the promoter (rs391957, rs17840762, rs17840761, rs11355458) and in the 3' untranslated region (UTR) (rs16927997, rs1140763, rs12009) and possible risk of chronic HBV infection were assessed in a case-control study. 496 cases and 539 individually matched healthy controls were genotyped. Results: Overall, no associations were observed in genotypic analyses. In addition, haplotypes and diplotypes combining those SNPs in the promoter or in the 3' UTR in high linkage disequilibrium (LD) were also not associated with HBV risk. Conclusion: These observations do not support a role for GRP78 polymorphisms in HBV infection in a predominantly Chinese Han population. [ABSTRACT FROM AUTHOR]

In order to solve the complex multi-objective optimal performance design of large-scale injection molding machines, NSGA-II is used to find a much better spread of design solutions and better convergence near the true Pareto-optimal front. The combination of the design method and the injection molding machine is discussed. Screw diameter performance, stick inside distance performance, mold moving route performance and mold-locked force performance are chosen as the four main performance evaluation indexes. Some related parameters are associated to get a performance indication. And performance optimization design parameter constraints are listed to make the design solutions to have practical significance. The mathematical models of two objectives and the mathematical models of three objectives are analyzed. Finally, the instance of HTF180X1N large-scale injection molding machine is taken as an example to demonstrated that such method is effective and practical. [ABSTRACT FROM AUTHOR]

In this paper, adaptive QoS provisioning schemes are proposed for CDMA wireless networks. The proposed schemes consist of two stages. In the first stage, a call admission control (CAC) and a bandwidth allocation schemes are proposed to determine the bandwidth assignment for new connections according to available bandwidth and adaptable range of active connections. The proposed methods utilize the Markov chain model to estimate the required bandwidth for all connections. This Markov chain model considers the traffic characteristics of both the incoming call request and the existing connections, and estimates the resulting quality of service (QoS). In the second stage, Net-CBK and Net-Share schemes are presented to regulate the active connections according to call blocking rates and unused bandwidth. From the simulation results, the proposed schemes are able to carry more connections and improve system utilization. [ABSTRACT FROM AUTHOR]

This paper presents a new channel assignment scheme that efficiently improves the spatial frequency–spectrum reuse in a wireless network with heterogeneous demands, in which the cells are partitioned into a lot of clusters. Since the channel demands of each cell are different, this scheme adopts two stages to effectively assign channels. In the first stage, the cluster-based scheme allocates a number of channels to the cells of each cluster for satisfying the requirement of co-channel reuse. The channel demand of majority cells will be satisfied in this stage. In the second stage, when the channel requirement of most cells has been fulfilled, the tree-based assignment scheme allocates channels for the minority cells, which are still lacking of channels. Simulation results showed that the proposed scheme is superior to the previous schemes. Copyright © 2005 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this paper, two reliability measures, Markov-chain distributed program reliability (MDPR) and Markov-chain distributed system reliability (MDSR) are first introduced to accurately model the reliability of distributed computing system (DCS). Based on this Markov-chain model, an effective link arrangement scheme is developed for maximizing the reliability. This scheme may assign the link with lower failure rate to more influential network segment. In this way, the whole system can obtain maximum reliability under the constraint of cost. This scheme is compared with some random arrangements and the optimal solution, and it is shown that the proposed scheme approaches to the optimal solution. [ABSTRACT FROM AUTHOR]

The single crystal nickel salicylate tetrahydrate was prepared with the rheological phase reaction method from nickelous hydroxide and salicylic acid. The crystal structure was determined. It is monoclinic, space group P21/ n, a = 0.678 74(3), b = 0. 515 91 (2), c = 2. 313 30(9) nm, β = 90. 928 6(17)° V = 0. 809 94 (6) nm3, Z = 2, ϱcaled=1.661 g· cm−3. Final R indices: R = 0. 027 9 and ω R = 0.065 0[ I>2σ( I)]. The thermal decomposition mechanism in an inert atmosphere was investigated via. TG, DTG and DTA. The thermal decomposition products were characterized with IR and micro-powder X-ray diffraction method. A new coordination polymer (NiC6H4O) n as an intermediate product and nanoscale metal nickel were obtained in the ranges of 364–429 °C and 429–680 °C, respectively. [ABSTRACT FROM AUTHOR]

High spin states of the odd-odd nucleus 92Nb are investigated using the 82Se (14N, 4n)92Nb reaction at a beam energy of 54 MeV. The level scheme of the 92Nb was extended up to Jπ =(16+) at about 7.3 MeV and Jπ=(21−) at about 9.7 MeV. According to systematic analyses and a comparison with the neighboring nucleus, the higher spin states could be interpreted by the multi-particle excitations in the π(f5/2,p3/2,p1/2,g9/2)⊗ν(p1/2,g9/2,d5/2, g7/2) configuration space. [ABSTRACT FROM AUTHOR]

High-spin states in 189Pt are populated through the heavy-ion fusion-evaporation reaction176Yb (18O, 5n)189Pt at 87MeV beam energy. An array consisting of 13 HPGe detectors is used in conjunction with the plunger device in CIAE. The lifetimes of two levels in the yrast band are determined by using the recoil distance Doppler shift method. The transition quadrupole moments Qt are extracted. The results show that the state has a much larger Qt value than that of the ground state, whereas the value deceases quickly with spin increasing. This may contribute to the shape driving effect of the quasi-neutron from the i13/2 orbital. [ABSTRACT FROM AUTHOR]

The distribution of He in η-Fe2C has been studied by first-principles calculations. The formation energies of interstitial He and substitutional He (replacing Fe) are 3.76 eV and 3.49 eV, respectively, which are remarkably smaller than those in bcc Fe, indicating that He is more soluble in η-Fe2C than in bcc Fe. The binding potencies of both a substitutional-interstitial He pair (1.28 eV) and a substitutional-substitutional He pair (0.76 eV) are significantly weaker than those in bcc Fe. The binding energy between the two He atoms in an interstitial–interstitial He pair (0.31 eV) is the same as that in bcc Fe, but the diffusion barrier of interstitial He (0.35 eV) is much larger than that in bcc Fe, suggesting that it is more difficult for the interstitial He atom to agglomerate in η-Fe2C than in bcc Fe. Thus, self-trapping of He in η-Fe2C is less powerful than that in bcc Fe. As a consequence, small and dense η-Fe2C particles in ferritic steels might serve as scattered trapping centers for He, slow down He bubble growth at the initial stage, and make the steel more swelling resistant. [ABSTRACT FROM AUTHOR]