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Tomato spot wilt virus (TSWV) and tomato yellow leaf curl virus (TYLCV) are highly harmful viruses in agricultural production, which can cause serious economic losses to crops and even devastating consequences for vegetable yield in some countries and regions. Although the two viruses belong to different families and have different transmission vectors, they share most hosts.This study aimed to examine the transcriptomic expression of single and mixed inoculations of TSWV and TYLCV, leading to antagonism using high-throughput RNA sequencing.We confirmed the single and mixed infections of these viruses in Nicotiana benthamiana (N. benthamiana) by artificial inoculation. And the expression changes of related genes and their biological functions and pathways during the mixed infection of TSWV and TYLCV were analyzed by comparative transcriptome.Basically, similar symptoms were observed in the plants singly infected with TSWV and co-infected with TYLCV; the symptoms of TYLCV in the co-infected plants were not obvious compared with single TYLCV infections. When inoculated with TYLCV, the accumulation of the virus significantly reduced in single and mixed infections with TSWV; the TSWV accumulated slightly less in co-infection with TYLCV, whereas this reduction was much smaller than that of TYLCV. The results suggested that TSWV had an antagonistic effect on the accumulation of TYLCV in N. benthamiana. It mainly focused on the changes in unique differentially expressed genes (DEGs) caused by the co-infection of TSWV and TYLCV. The eight pathways enriched by upregulated DEGs mainly included amino acid biosynthesis, citrate cycle (or tricarboxylic acid cycle, TCA cycle), and so on. However, only pentose phosphate pathway (PPP) and peptidoglycan biosynthesis could be downregulated in the Kyoto Encyclopedia of Genes and Genomes pathway in which peptidoglycan biosynthesis was involved in upregulated and downregulated pathways.The antagonistic effect of TSWV on TYLCV in N.benthamiana and the change trends and specific pathways of DEGs in this process were found. Our study provided new insights into the host regulation and competition between viruses in response to TSWV and TYLCV mixed infection.

In this paper, we investigate the distributed finite-time secondary voltage control for the islanded microgrid with droop-controlled, inverter-based distributed generations. By introducing an error function, a nonsingular terminal sliding manifold is established, then the secondary voltage control is converted to a tracking consensus problem of the distributed nonsingular terminal sliding mode control. In the proposed control scheme, each distributed generation unit only requires its local information and the information from neighbors, which means only a simple communication network is needed. Furthermore, the distributed controller can adjust the voltage magnitude to its reference value in despite of dynamic uncertainties and bounded external disturbances. Numerical simulations are presented to demonstrate the effectiveness of the proposed control protocol.

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The main purpose of this paper is to study the problem of fault detection and estimation for switched systems based on DC–DC converters. Firstly, we transform DC–DC converters into switched systems. Secondly, to achieve the purpose of the fault detection and estimation, we design a sliding mode observer(SMO) to produce residual signal. By comparing the set threshold and the residual produced by SMO, we can detect whether a fault has occurred. Meanwhile, fault estimation is realized through the method of fault reconstruction. Finally, in order to show the feasibility of this sensor fault detection and estimation, the simulation of three sensor faults which include open-circuit, gain deviation and noise abnormity is given in this paper.

Rhizoctonia cerealis, Bipolaris sorokiniana, and Fusarium spp. are three wheat-damaging soil-borne fungal pathogens causing sharp eyespot, common root rot, and crown rot, respectively. This study aimed to develop a multiplex PCR (mPCR) system to simultaneously detect these fungal pathogens. The mPCR assay was performed on wheat seedlings collected from a field in the Shandong Province. Specific primers were designed on the basis of the sequences of following genes: internal transcribed spacer (ITS) of R. cerealis, ITS of B. sorokiniana, and translation elongation factor (TEF1-α) of Fusarium spp., generating amplicons of 174, 418, and 600 bp, respectively. The mPCR system was optimized through an orthogonal design L18 (37) (three levels of five factors: three sets of primers, Taq DNA polymerase, and dNTPs) and statistical analysis. No nonspecific products were obtained upon amplification of nontarget species of the fungi. Sensitivity analysis revealed that the limit of detection of the mPCR assay for each pathogen was 100 pg. The mPCR results were further confirmed via subsequent visual diagnosis. The system developed herein provides a rapid, effective, and valuable method to simultaneously detect three soil-borne pathogens, thus facilitating prompt treatment and prevention of root diseases of wheat.

This paper finishes the fault detection (FD) problem for switched singular systems with all subsystems unstable. Considering the particularity of singular systems, the regularity and impulse-free property analysis on it are carried out. Utilizing a time-driven switching strategy, a switching signal is proposed and the finite-time stability is guaranteed firstly. Then, with the help of discretized Lyapunov function, a piecewise Lyapunov function is employed to accomplish the finite-time boundedness with L2-gain analysis. Through transferring the fault detection filters design into the L2-gain analysis, we can obtain the existence conditions of the FD detector via linear matrices inequalities (LMIs). Finally, the effectiveness and validity are illustrated by two examples.

A source of premium animal protein, crustaceans are widely distributed and cultivated around the world. Short-term or long-term starvation events occur frequently owing to natural environment changes or manual management strategies in the life cycle of crustaceans. The result induced by starvation is that somatic growth of crustaceans will be retarded, while the immune mechanism is activated in this process. The aim of this study was to investigate whether the immune regulatory pathways are involved in the growth of crustaceans. Twelve muscle tissue transcriptomes of the oriental river prawn Macrobrachium nipponense were sequenced across four fasting stages lasting 0, 7, 14 and 21 d. The results showed that three immune-related pathways were involved in the growth of M. nipponense by regulating actin expression inducing the chemokine signaling pathway, the leukocyte transendothelial migration pathway and the FcR-mediated phagocytosis pathway. Furthermore, we employed RNA interference (RNAi) to further verify the effects that genes involved in the pathways had on regulating growth of M. nipponense. Comparative transcriptional analysis and RNA interference reveal that VASP and WAVE positively regulated the expression of actin; however, WASP negatively regulated the expression of actin. This is the first report that the immune regulatory pathways play key roles in the growth of crustaceans. Our results will not only provide an entirely new understanding of the immune mechanism of crustaceans from a unique angle but also further enrich and develop the theory of growth and developmental biology in crustaceans.

Melon necrotic spot virus (MNSV) can cause significant economic losses due to decreased quality in cucurbit crops. The current study is the first to use reverse transcription loop-mediated isothermal amplification (RT-LAMP) for detection of MNSV. A set of four LAMP primers was designed based on the coat protein gene sequence of MNSV, and a RT-LAMP reaction was successfully performed for 1 h at 62oC. The results of RT-LAMP showed high specificity for MNSV and no cross-reaction with other viruses. Compared to traditional reverse transcription-PCR (RT-PCR), the RT-LAMP assay was 103-fold more sensitive in detecting MNSV. Due to its sensitivity, speed and visual assessment, RT-LAMP is appropriate for detecting MNSV in the laboratory.

This paper proposes a multi-exit evacuation model based on a continuous model for the pedestrian evacuation problem. Firstly, it is determined that the distance between pedestrians and exits, the pedestrian density near exits, and the width of exits are the main factors for exit selection. A pedestrian multi-exit selection model is defined by taking the three factors into account. Secondly, a pedestrian evacuation model is constructed by considering the impact of pedestrian psychological factors on expected speed and exit attractiveness. Finally, the multi-exit evacuation is simulated, and the pedestrian evacuation process is tested on three conditions. The effects of pedestrian density near the exit and the width of exit are analyzed on the final simulation. The simulation results show that the evacuation model can effectively simulate the pedestrian evacuation process in multi-exit scenarios.

In this paper, secondary voltage control scheme for a droop-controlled inverter-based islanded microgrid is addressed. Motivated by the cooperative control theory of multi-agent systems, the proposed secondary voltage control is a distributed scheme which uses a simple communication network. Two nonlinear control algorithms are applied to restore the voltage of each distribution generation (DG) to the reference value. The simulation results verify the effectiveness of the proposed secondary voltage control for a prototype microgrid system.

This paper conducts a series of evacuation trials to observe human behavior under different ship rolling angles modeled as a function of wind-wave dynamics. A velocity reduction model is then developed with the consideration of human characteristics, ship rolling angles and wind-wave dynamics. Based on the open source simulation software FDS Evac, the proposed model is implemented and validated through the simulation of the 7th deck of Bohai Cuizhu passenger ship, the largest Ro-Ro passenger ship in China.

High molecular weight, hyperbranched polyarylenes were synthesized in high isolation yields by the copolycyclotrimerizations of 2,5-diethynylthiophene (1), 4,4′-biphenyldiyne (2), and 2,7-diethynylfluorenes (3) with 1-heptyne (4) and 1-dodecyne (5) using TaCl5–Ph4Sn as the catalyst in toluene. The structures of the polymers were characterized by IR, NMR, TGA, and UV analyses. All the polymers exhibited outstanding thermal stability and emitted strong blue light, whose intensities are higher than that of poly(1-phenyl-1-octyne), a well-known highly emissive polyacetylene. Little red shift was observed in the photoluminescence of the polymer thin films. The polymers strongly attenuated intense pulses of 532 nm laser pulses.

Diyne polycyclotrimerizations initiated by transition-metal catalysts afforded hyperbranched polyphenylenes, which exhibited low viscosity, outstanding thermal stability, and small optical dispersion. Under optimized reaction conditions, polycyclotrimerizations of 1,8-nonadiyne (1) and 1,9-decadiyne (2) catalyzed by TaCl5−Ph4Sn produced hyperbranched poly(1,2,4-benzenetriyl-1,5-pentanediyl) (3) and poly(1,2,4-benzenetriyl-1,6-hexanediyl) (4),1-5 respectively, in high yields (up to 93%). The polymers were completely soluble and film-forming, and possessed high molecular weights (Mw up to ∼1.4 × 106) but low intrinsic viscosities ([η] down to 0.13 dL/g). Their structures and properties were analyzed and evaluated by IR, UV, NMR, SEC, TGA, DSC, spectrofluorometry, light scattering, and spectroellipsometry. The structural characterizations confirmed the expected hyperbranched molecular architectures of 3 and 4 (comprising of 1,2,4-benzene rings and α,ω-alkyl spacers) and revealed the regioselective feature of...

Although the university course timetabling problem (UCTP) is an old, classical problem in the field of optimization problems, there are still a few challenges for the practical-relevant problems considering customers' requirements. In particular with respect to the UCTP of China, the timetable planning based on the uniform teaching resources of a university for all degree types of undergraduates and graduates, is still not considered and tackled in the previous researches. In this paper, a novel greedy heuristic approach for UCTP is presented with considering complex multi-constraint conditions on the basis of the uniform teaching resources of a university, which include students, teachers and classrooms with feasible timeslots, respectively. Firstly, the constraints are modelled and then the objective function is proposed based on the evenness for all the curriculums of a student and a teacher's satisfaction for his/her lecturing time. Secondly, transform the constraints to relational calculus among of the variables expressed by relation algebra; thereby the heuristic rules are formed by the relational calculus. And the greedy strategies are applied to search the optimal solutions in the remaining parts of feasible solution space. A greedy heuristic algorithm is designed to implement the approach. Finally, a course timetabling instance from a graduate school is carried out and the result adopted in the graduate school show that the novel greedy heuristic algorithm is effective and the runtime is significantly shortened comparing with the earlier approaching used in the timetabling system.

Poly (styrene-b-isoprene) (PS-b-PI) star-block copolymers were studied by triple detector size exclusion chromatography (SEC3), utilizing a combination of refractive index (RI), right angle light scattering (RALLS), and differential viscosity (DV) detectors. The relationships between the number of arms, the composition, and molecular size of the star polymers were investigated. The effect of the number of arms of the star polymer on elution behavior was established and compared to a linear polystyrene calibration curve. It was found that universal calibration was valid for star polymers having up to 32 arms. The branching parameters (g and g') were calculated from intrinsic viscosity and radius of gyration data. The results indicate that, in addition to molecular weight determinations, much useful conformational information on star-block copolymers can be obtained from SEC3. The technique is an especially useful tool for characterizing branched copolymers, which are difficult to characterize by conventional SEC.

The hyperbranched copolymers were obtained by the atom transfer radical copolymerization of p-(chloromethyl)styrene (CMS) with N-cyclohexylmaleimide (NCMI) catalyzed by CuCl/2,2′-bipyridine (bpy) in cyclohexanone (C6H10O) or anisole (PhOCH3) with CMS as the inimer. The influences of several factors, such as temperature, solvent, the concentration of CuCl and bpy, and monomer ratio, on the copolymerization were subsequently investigated. The apparent enthalpy of activation for the overall copolymerization was measured to be 37.2 kJ/mol. The fractional orders obtained in the copolymerization were approximately 0.843 and 0.447 for [CuCl]0 and [bpy]0, respectively. The monomer reactivity ratios were evaluated to be rNCMI = 0.107 and rCMS = 0.136. The glass transition temperature of the resultant hyperbranched copolymer increases with increasing fNCMI, which indicates that the heat resistance of the copolymer has been improved by increasing NCMI. The prepared hyperbranched CMS/NCMI copolymers were used as macroinitiators for the solution polymerization of styrene to yield star-shaped poly(CMS-co-NCMI)/polystyrene block copolymers by atom transfer radical polymerization. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 1992–1997, 2000

GEM 91 (gene expression modulator) is a 25-mer oligonucleotide phosphorothioate complementary to the gag initiation site of HIV-1. GEM 91 has been studied in various in vitro cell culture models to examine inhibitory effects on different stages of HIV-1 replication. Experiments were focused on the binding of virions to the cell surface, inhibition of virus entry, reverse transcription (HIV DNA production), inhibition of steady state viral mRNA levels, inhibition of virus production from chronically infected cells, and inhibition of HIV genome packaging within virions. Experiments were also performed in vitro in an attempt to generate strains of HIV with reduced sensitivity to GEM 91. We observed sequence-dependent inhibition of virus entry/reverse transcription and a reduction in steady state viral RNA levels. We also observed sequence-independent inhibition of virion binding to cells and inhibition of virus production by chronically infected cells. Using in vitro methods that were successful in generating HIV strains with reduced sensitivity to AZT, we were unable to generate strains with reduced sensitivity to GEM 91.

The capacity of Wireless Mesh Networks can be substantially increased by equipping each node with multi-radio which allows for simultaneous transmissions, but the interference between those transmission links is still high without appropriate channel assignment due to the limited nonoverlapping channels, further optimization is needed to carefully assign channels for radios. In this paper, we formulate a centralized channel allocation optimization framework which considers the traffic load of each link to effectively reducing the overall network interference and increase network throughput. The genetic algorithm (GA) is provided to approximately attaining the optimal solution to the optimization problem under our proposed framework. Simulation results are given to show that our scheme can improve the overall network performance considerably.

NF-kappa B is a nuclear protein of the rel oncogene family capable of enhancing transcription of several cellular genes, including IL-2 and the IL-2 receptor, and viral genes transcribed from the HIV-1 LTR. It has been reported that HIV-1 protease may cleave the NF-kappa B precursor to its active form in vitro. In this study the effects of HIV protease on NF-kappa B precursor activation were examined in Jurkat T cells by introducing a protease expression vector into the cells. Increased NF-kappa B activity was observed and this increased activity was blocked by a specific inhibitor of the viral protease. Viral transcription, as measured using LTR-CAT assays, was only slightly enhanced in the HIV-protease expressing cells, while secretion of IL-2 and expression of the IL-2 receptor were not affected. The limited activation of NF-kappa B by HIV protease appears unlikely to have a significant effect on virus expression or T cell function.

We have developed an immunotherapeutic approach with potential application in the treatment of viral and malignant disease. We show that primary CD8+ T cells isolated from peripheral blood can be genetically modified by retroviral transduction to express high levels of universal (major histocompatibility complex-unrestricted) chimeric T- cell receptors specific for human immunodeficiency virus (HIV) antigens. Two classes of HIV-specific URs in which the antigen-binding domain is comprised of either CD4 or a single-chain antibody are capable of activating a number of T-cell effector functions in response to target cells, including cytolysis, in a highly sensitive and specific manner. Importantly, we have addressed a number of issues which, although particularly relevant to the clinical application of this approach in the treatment of HIV infection, may also impact on the potential of UR immunotherapy for other disease targets. The UR immunotherapeutic system is particularly suited for evaluation in the clinical setting.

Ceramide, an intracellular lipid mediator of tumor necrosis factor alpha (TNF-alpha) action, was studied for its effects on the expression of the proviral human immunodeficiency virus type 1 genome in latently infected myelomonocytic cell lines U-1IIIB and OM-10.1. Ceramide treatment resulted in a 20- to 100-fold enhancement of HIV production in these cells. Ceramide also enhanced the expression of the chloramphenicol acetyltransferase gene directed by a human immunodeficiency virus type 1 long terminal repeat in transfected U-937 cells, indicating that ceramide acts at the level of viral transcription. These observations suggest that the TNF-ceramide signaling system may be involved in the regulation of HIV expression in certain myeloid cell types.

Objective:To report eight cases of inferior vestibular neuritis, in order to raise awareness of this new subtype of vestibular neuritis.Materials and methods:We retrospectively analysed 216 patients (104 males and 112 females; age range 10–64 years; mean age 38.4 years) with full clinical documentation who had attended our hospital's vertigo clinic between May 2007 and December 2008. All patients underwent systematic investigation, including hearing tests, radiology, caloric testing and vestibular evoked myogenic potential testing.Results:Of 216 patients with vestibular neuritis, eight cases were diagnosed as inferior vestibular neuritis, based on comprehensive analysis of test data. The clinical features of these eight patients were consistent with the characteristics of vestibular neuritis. The results of pure tone audiometry and caloric testing were normal, and the possibility of central lesions was excluded by cerebral computed tomography or magnetic resonance imaging on admission. Six cases had unilateral loss of vestibular evoked myogenic potentials, whereas two had a unilateral lower amplitude of vestibular evoked myogenic potentials.Conclusions:Inferior vestibular neuritis is a novel subtype of vestibular neuritis, which involves the inferior vestibular nerve alone. Vestibular evoked myogenic potential testing is a useful aid to the diagnosis of inferior vestibular neuritis.

In this paper, a direction of arrival (DOA) estimation algorithm is proposed for uplink MC-CDMA system with antenna array. By utilizing the orthogonality of spreading codes and frequency diversity of MC-CDMA the users' signals are separated and enhanced, and the multiple access interference (MAI) is suppressed. After that the conventional subspace based DOA estimation is applied to estimate the DOAs of users' signals. Simulation results show the efficiency of the proposed algorithm.

We have developed a humanized, bispecific immunoadhesin-antibody (BsIAb) that targets and kills HIV-infected cells. Comprised of CD4-IgG and humanized anti-CD3-IgG, this BsIAb is bifunctional. First, in targeting, it exploits the natural affinity of CD4 for gp120 to target the BsIAb to HIV-infected cells, and second, it recruits and activates, through its anti-CD3 moiety, cytotoxic T lymphocytes (CTL) to lyse target cells in a non-MHC restricted manner. To produce purified BsIAb from supernantants of transfected mammalian cells, we designed a three-step recovery scheme based on the structural elements of this heterotrimeric protein. The ability of purified BsIAb to specifically lyse HIV-infected target cells was demonstrated using CTL from two different sources: whole peripheral blood lymphocyte (PBL) fractions and pure CTL preparations. In contrast, a human anti-gp120 antibody mediated lysis of HIV-infected target cells only with PBL fractions and not with purified CTL. Moreover, lysis observed in the presence of the human anti-gp120 antibody was completely blocked in the presence of human serum (which competes for Fc gamma receptor binding), whereas BsIAb-mediated lysis of target cells was not affected. We measured the monovalent affinities of BsIAb for HIV-gp120 on infected cells and for CD3 epsilon on CTL. Relative to the bivalent parent molecules, CD4/gp120 affinity in the BsIAb is unchanged, whereas anti-CD3/CD3 is substantially decreased. We further demonstrated by fluorescence microscopy that physical association of CD3+ cells with gp120-expressing cells occurs only in the presence of BsIAb. Thus, the cytocidal activity of BsIAb in the presence of serum reflects its unique ability to recruit CTL as effector cells and highlights a potentially important advantage of this type of construct over antibodies for HIV-directed therapy.

In this report we use several previously described methods, in novel combination, to establish a sensitive and flexible nonradioactive method. First, we prepared single-stranded digoxigenin-labeled probes using a high-efficiency polymerase chain reaction (PCR) method (4). For detection of RNA, blots were hybridized with probes containing digoxigenin and then incubated with alkaline phosphatase-conjugated anti-digoxigenin antibody. Bound probe was rapidly detected with X-ray film using localized light emission from the reaction of alkaline phosphatase with lumigen-paraphenylenediamine substrate (5). This method allows flexibility in probe sequence selection, independent of restriction enzyme site location, and it works well with small probes. This approach allows sensitive differential analysis of closely related members of a gene family.

/L, no known infected, andnormal genitourological examination at the time ofspecimen donation. Protease-gene sequences weredetermined for 11 blood and eight semen virus clones frompatient A who had not received antiretroviral therapy, andfrom nine blood and nine semen virus clones from patient Bwho had been on antiretroviral therapy for several years,including a protease inhibitor for 4 months. The sequenceswere aligned for maximum homology and phylogeneticanalysis were done (figure).Protease-gene sequences of all clones contained severalmutations relative to the reference virus, hxb2. Thephylogenetic analyses of the sequences from each patientrevealed two distinct families of viruses, one in the bloodand one in the semen. The differences between the familiesranged from four to seven or from four to eight aminoacidsubstitutions for patients A and B, respectively. Bloodclones from patient B contained mutations at aminoacidresidues 36(I), 54(V), 63(P), and 82(A), characteristic ofemerging resistance to the protease inhibitor. By contrast,protease resistance conferring mutations were not found inthe semen virus clones from patient B.These findings support the concept that semen HIV-1arises from a distinct reservoir of HIV-1 infection whichmay be isolated from antiretroviral therapy and mayfunction independently in the pathobiology of HIV-1disease. This suggests that consideration of the specialisedfeatures of the semen compartment needs to be included indisease monitoring and the design of treatment strategies.