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Root-knot nematodes (RKNs) which can infect almost all crops lead to huge economic losses in agriculture around the world. Unavailability of effective and environmentally friendly control of RKNs provides an opportunity to nematicidal bacteria. Fictibacillus phosphorivorans G25-29 is a gram-positive and spore-forming bacterium with nematicidal capability against root-knot nematodes and free-living nematode Caenorhabditis elegans. Here, we report the complete genome of F. phosphorivorans G25-29, containing a circular chromosome and encoding nine potential nematicidal factors which may contribute to its nematicidal activity.

This study aims at predicting affective states during programming using keyboard and mouse data. The article proposes and evaluates a novel set of features under programming context to predict affective states. Fourteen undergraduate participants performed three programming tasks of varying difficulties. At the completion of each task, participants reported their affective states by viewing webcam videos and screen recordings. Features extracted from keyboard and mouse logs were used to train multiple classifiers. Among trained classifiers, feedforward neural network recognized positive, neutral and negative states with 52.9% accuracy. The overall Cohen's Kappa reached 0.27. Without neutral states, the classifiers were able to differentiate positive and negative states with 74.1% accuracy and 0.48 Kappa. Our approach demonstrates improved ability of predicting self-labelled affective states of programmers from keyboard and mouse data, without using specialized sensors, and potential of emotional feedback to programmers during learning to deliver better experience.

Despite the successful application of crystal proteins (Cry) from Bacillus thuringiensis as biological control agents against insects, there is an increasing demand to identify new Cry toxins having higher toxicity and broad-spectrum activity against insects and plant-parasitic nematodes. To find novel Cry toxins, we screened 100 whole-genome sequences of B. thuringiensis Surprisingly, in addition to full Cry toxins, we found partial sequences, such as typical N-terminal or C-terminal regions with conserved domains, widely distributed among 20 strains of B. thuringiensis In order to further elucidate the functions of partial genes, here, we selected a partial sequence from strain C15, having 28% similarity with the N terminus of Cry5Ba and lacking a typical C terminus, and denoted it Cry5B-like N terminus. This fragment when coexpressed as a fusion protein with the C terminus of Cry5Ba (N-C fusion protein) produces pyramidal crystals. A recombinant N-C fusion protein having a 50% lethal concentration (LC50) of 23.7 μg/ml severely affected the life span, growth, and survival rate of nematodes. Light microscopy showed damage to the intestine of nematodes, confirming the pathogenicity of the N-C fusion protein. Last, the green fluorescent protein (GFP)-labeled mutant Caenorhabditis elegans FT63 showed significant damage to the intestine upon feeding N-C fusion toxin compared to the control. These results imply that partial genes can be a source of new Cry toxins, and further understanding about functions of partial cry genes can help in the study of the evolutionary strategy of B. thuringiensis to produce the multidomain toxins.IMPORTANCE Genomic analysis revealed that coding sequences for N termini and C termini of crystal proteins are widely distributed in B. thuringiensis We found Cry5B-like N terminus, lacking typical C terminus, was unable to be expressed in wild-type strain C15. However, its fusion with the C terminus of Cry5Ba not only was successfully expressed but also exhibited activity against the nematodes. This study provides insight into a potential source for novel Cry toxins.

Understanding the genetic basis of host shifts is a key genomic question for pathogen and parasite biology. The Bacillus cereus group, which encompasses Bacillus thuringiensis and Bacillus anthracis, contains pathogens that can infect insects, nematodes, and vertebrates. Since the target range of the essential virulence factors (Cry toxins) and many isolates is well known, this group presents a powerful system for investigating how pathogens can diversify and adapt to phylogenetically distant hosts. Specialization to exploit insects occurs at the level of the major clade and is associated with substantial changes in the core genome, and host switching between insect orders has occurred repeatedly within subclades. The transfer of plasmids with linked cry genes may account for much of the adaptation to particular insect orders, and network analysis implies that host specialization has produced strong associations between key toxin genes with similar targets. Analysis of the distribution of plasmid minireplicons shows that plasmids with orf156 and orf157, which carry genes encoding toxins against Lepidoptera or Diptera, were contained only by B. thuringiensis in the specialized insect clade (clade 2), indicating that tight genome/plasmid associations have been important in adaptation to invertebrate hosts. Moreover, the accumulation of multiple virulence factors on transposable elements suggests that cotransfer of diverse virulence factors is advantageous in terms of expanding the insecticidal spectrum, overcoming insect resistance, or through gains in pathogenicity via synergistic interactions between toxins., IMPORTANCE Population genomics have provided many new insights into the formation, evolution, and dynamics of bacterial pathogens of humans and other higher animals, but these pathogens usually have very narrow host ranges. As a pathogen of insects and nematodes, Bacillus thuringiensis, which produces toxins showing toxicity to many orders of insects and other invertebrates, can be used as a model to study the evolution of pathogens with wide host ranges. Phylogenomic analysis revealed that host specialization and switching occur at the level of the major clade and subclade, respectively. A toxin gene co-occurrence network indicates that multiple toxins with similar targets were accumulated by the same cell in the whole species. This accumulation may be one of the strategies that B. thuringiensis has used to fight against host resistance. This kind of formation and evolution of pathogens represents a different path used against multiple invertebrate hosts from that used against higher animals.

This paper examines various aspects of the design process and subsequent field test measurements of a large and complex substation grounding system. The study and measurements show that soil layering and lead interference can have a significant impact on the appropriate test location that yields the exact substation ground impedance. Applying a specific percentage rule such as the 61.8% rule for uniform soils to obtain the true ground impedance may lead to unacceptable errors for large grounding systems. This poses significant problems when attempting to validate a design based on raw test data that are interpreted using approximate methods to evaluate substation ground impedance, and determine ground potential rise (GPR), touch and step voltages. Advanced measurement methodologies and modern software packages were used to obtain and effectively analyze fall of potential test data, compute fault current distribution, and evaluate touch and step voltages for this large substation. Fault current distribution between the grounding system and other metallic paths were computed to determine the portion of fault current discharged in the grounding system. The performance of the grounding system, including its GPR and touch and step voltages, has been accurately computed and measured, taking into account the impedance of the steel material used of the ground conductors and circulating currents within the substation grounding system.

Due to the rapidly increasing prevalence of multidrug-resistant bacterial strains, the need for new antimicrobial drugs to treat infections has become urgent. Bacteriocins, which are antimicrobial peptides of bacterial origin, are considered potential alternatives to conventional antibiotics and have attracted widespread attention in recent years. Among these bacteriocins, lantibiotics, especially two-component lantibiotics, exhibit potent antimicrobial activity against some clinically relevant Gram-positive pathogens and have potential applications in the pharmaceutical industry. In this study, we characterized a novel two-component lantibiotic termed thusin that consists of Thsα, Thsβ and Thsβ' (mutation of Thsβ, A14G) and that was isolated from a B. thuringiensis strain BGSC 4BT1. Thsα and Thsβ (or Thsβ') exhibit optimal antimicrobial activity at a 1:1 ratio and act sequentially to affect target cells, and they are all highly thermostable (100°C for 30 min) and pH tolerant (pH 2.0 to 9.0). Thusin shows remarkable efficacy against all tested Gram-positive bacteria and greater activities than two known lantibiotics thuricin 4A-4 and ticin A4, and one antibiotic vancomycin against various bacterial pathogens (Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus (MRSA), Staphylococcus sciuri, Enterococcus faecalis, and Streptococcus pneumoniae). Moreover, thusin is also able to inhibit the outgrowth of Bacillus cereus spores. The potent antimicrobial activity of thusin against some Gram-positive pathogens indicates that it has potential for the development of new drugs.

Gas or liquid flow through small channels has become more and more popular due to the micro-electro-mechanical systems (MEMS) fabrication technologies such as micro-motors, electrostatic comb-drive, micro-chromatographs, micro-actuators, micro-turbines and micro-pumps, etc. The flow conditions in and around these systems are always recognized as typical transitional regimes. Under these conditions, the mean free path of gas molecules approaches the characteristic scale of the micro-devices itself, and due to the little collisions the heat and momentum cannot equilibrate between the wall and fluids quickly. Couette flow is a simple and critical model in fluid dynamics which focuses on the mechanism of the heat transfer in shear-driven micro-cavities or micro-channels. Despite numerous work on the numerical solutions of the Couette flow, how to propose stable and accurate slip boundary conditions in rarefied flow conditions still remains to be elucidated. In this paper, converged solutions for steady-state ...

Combining plasma activation and cross-reactivity of sensor array, we have developed a plasma-assisted cataluminescence (PA-CTL) sensor array for fast sensing and discrimination of gaseous hydrocarbons, which can be potentially used for fast diagnosis of lung cancer. Based on dielectric barrier discharge, a low-temperature plasma is generated to activate gaseous hydrocarbons with low cataluminescence (CTL) activities. Extremely increased CTL responses have been obtained, which resulted in a plasma assistance factor of infinity (∞) for some hydrocarbons. On a 4 × 3 PA-CTL sensor array made from alkaline-earth nanomaterials, gaseous hydrocarbons showed robust and unique CTL responses to generate characteristic patterns for fast discrimination. Because of the difference in the component of hydrocarbons in breath, exhaled breath samples from donors with and without lung cancer were tested, and good discrimination has been achieved by this technique. In addition, the feasibility of multidimentional detection based on temperature was confirmed. It had good reproducibility and gave a linear range of 65-6500 ng/mL or 77-7700 ppmv (R > 0.98) for CH(4) with a detection limit of 33 ng/mL (38 ppmv) on MgO. The PA-CTL sensor array is simple, low-cost, thermally stable, nontoxic, and has an abundance of alkaline-earth nanomaterials to act as sensing elements. This has expanded the applications of CTL-based senor arrays and will show great potential in clinical fast diagnosis.

Currently, all the data processing strategies for functional magnetic resonance imaging (fMRI) utilize temporal informationpaying little attention to or totally ignoring frequency information. In this paper, a new method is proposed to detect the functional activation regions in the brain by using the frequency information of fMRI time series. The main idea is that the frequency entropy information (FEI) difference of fMRI data between task and control states is specified as brain activation index. The validity of the proposed FEI approach is confirmed by analyzing the result of the simulated synthesized data. Additionally, the comparison of receiver operating characteristic (ROC) curves acquired respectively from the proposed scheme, the statistical parametric mapping (SPM), and the Support Vector Machine (SVM) methods of fMRI data analysis indicate an obvious superiority of the former. In vivo fMRI studies of subjects with event-related experiment reveal that FEI method can enable the effective detection of brain functional activation.

A novel circularly polarized array designed for millimeter wave digital radar module was proposed and validated in this paper. The circularly polarized array was designed with single feeding point for easily integrating with front-end module. A new kind of medium filled circular cavity was employed as transition to connect the output of the T/R module and the feeding point of the array. TM010 mode was selected as the operating mode of the circular cavity based transition for its special field distribution. Good performance of flexibility, return-loss, axial ratio and radiation pattern were observed.

This paper presents an integrated approach for diagnosis and synthesis of production data for gas wells in Dina HPHT reservoir, where most of the production wells exhibit everlasting abnormal flow with limited analyzable data For production data diagnostics, we prove that for gas wells at high pressure stage (both reservoir pressure and wellbore flowing pressure are above 50MPa), the qg/(Ppi - Ppwf) versus tca plot for gas system can be substituted rigorously by qg/(Pi - Pwf) versus Gp/qg plot (similar form as liquid system) in Palacio-Blasingame decline type curve analysis; and for gas Flowing Material Balance (FMB) analysis, the qg/(Ppi - Ppwf) versus (qgtca)/[(Ppi - Ppwf)Cti] plot can be substituted by qg/(Pi - Pwf) versus Gg/(Pi - Pwf) plot. These reduced functions are used to generate simplified Blasingame diagnostic plot and FMB diagnostic plot for high pressure gas system. These simplified diagnostic plots, with no iterations or integrations when calculating, provide a quick and straightforward solution for instant detection of abnormal flowing data in field. In well production profile synthesis, the dependence of well OGIP on individual-well-flow-rate/reservoir-flow-rate ratio is given based on "pseudo-steady-state" flow theory in a multiwell reservoir. Interference effects are coupled into the analytical model by assigning varied OGIP in production profile synthesis, which reduce the risk of erroneous results in modeling long-term production profile for wells with limited analyzable history data and make the "generated" well behavior consistent with the multi-well-reservoir behavior.

The aim of the present study was to investigate the immune function of children with juvenile idiopathic arthritis (JIA). Flow cytometry and three-color direct immunofluorescence were used to examine cluster of differentiation (CD)3+ T-lymphocyte subsets and CD28/cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) expression in whole blood (using the no-wash method) from 36 children with JIA and 39 healthy children. During the active phase of JIA, CD28 expression on CD4+ T cells in children with JIA was significantly reduced; thus, CD4+CD28− T-cell frequency increased, suggesting that CD4+ T-cell and CD4+CD28− T-cell apoptosis was inhibited in patients with JIA. The continued survival of these immune-active T lymphocytes may promote the occurrence and development of JIA. CTLA-4 expression levels on CD4+ and CD8+ T cells in children with JIA during the active phase were significantly higher than those in normal controls. As the majority of CD4+ T cells in patients with JIA are CD28−, they cannot be inactivated by the interaction between CTLA-4 and B7, leading to continuously high levels of CTLA-4 expression on the surface of CD4+ T cells without functional effect. Hence, T lymphocytes are continuously kept in a highly activated state that is difficult to stop. During the resting phase, the CD4+ and CD8+ T-cell counts in children with JIA were similar to normal, and CD28 expression was also normal. This suggests that the frequency of CD4+CD28− T cells can be used as an indicator of the active phase of JIA. CTLA-4 expression on the surface of T cells in children with JIA during the resting phase was also similar to that in normal controls, suggesting that abnormal lymphocyte activation plays an important role in the active phase of JIA.

Burnett equations were originally derived in 1935 by Burnett by employing the Chapman-Enskog expansion to Classical Boltzmann equation to second order in Knudsen number Kn. Since then several variants of these equations have been proposed in the literature; these variants have differing physical and numerical properties. In this paper, we consider three such variants which are known in the literature as ‘the Original Burnett (OB) equations’, the Conventional Burnett (CB) equations’ and the recently formulated by the authors ‘the Simplified Conventional (SCB) equations.’ One of the most important issues in obtaining numerical solutions of the Burnett equations is their stability under small perturbations. In this paper, we perform the linearized stability (known as the Bobylev Stability) analysis of three-dimensional Burnett equations for all the three variants (OB, CB, and SCB) for the first time in the literature on this subject. By introducing small perturbations in the steady state flow field, the trajectory curve and the variation in attenuation coefficient with wave frequency of the characteristic equation are obtained for all the three variants of Burnett equations to determine their stability. The results show that the Simplified Conventional Burnett (SCB) equations are unconditionally stable under small wavelength perturbations. However, the Original Burnett (OB) and the Conventional Burnett (CB) equations are unstable when the Knudsen number becomes greater than a critical value and the stability condition worsens in 3D when compared to the stability condition for 1-D and 2-D equations. The critical Knudsen number for 3-D OB and CB equations is 0.061 and 0.287 respectively.

This paper describes the computations of hypersonic shock wave structure in a gas in rotational non-equilibrium using a newly developed simplified set of Burnett equations designated as Simplified Conventional Burnett (SCB) equations. Since the original formulation by Burnett, a number of variations to the original Burnett equations have been proposed and the differences among these variants and their merits/shortcomings have been described in the literature. A new variant is created based on the conventional Burnett equations for hypersonic flows by neglecting terms that are inversely proportional to the Mach number. This simplified set of conventional Burnett equations is linearly stable for small disturbances in contrast to the conventional Burnett equations which suffer from Bobylev instability. To simulate the rotational non-equilibrium effect in a diatomic gas, both the Navier–Stokes (NS) and the SCB equations are modified by including a rotational non-equilibrium relaxation model. The flow variables (density, translational and rotational temperature) in a typical 1-D shock at different Mach numbers (1.2, 5, and 10) in Nitrogen are computed using SCB and NS equations and are compared with the DSMC results. SCB calculations are in close agreement with the DSMC results at high Mach numbers.

Transposon mutagenesis and subsequent phenotype-driven screening have been extensively used to annotate gene function and uncover the mechanisms of biological phenomena. During this process, the resulting phenotypic differences are specifically attributable to the disrupted genes. In this study, the complementation of the mini-Tn10 transposon-disrupted gene gntP did not restore the germination ability of the Bacillus thuringiensis MT1518-1 mutant to the wild-type level. Genome sequencing identified 186 unlinked mutations on the chromosome of the mutant MT1518-1, including one frameshift mutation in the germination-related gene exsA. We randomly selected 19 mini-Tn10 mutants for high throughput genome sequencing. The sequencing data revealed that incidental mutations occurred frequently on their chromosomes, including 2343 single-nucleotide polymorphisms, three insertions and one deletion. We also found that stressful conditions are the underlying cause for the appearance of incidental mutations. Caution is warranted when attributing the observed phenotypic changes to the transposon-disrupted genes.

Plant-parasitic nematodes were found in 4 of the 12 clades of phylum Nematoda. These nematodes in different clades may have originated independently from their free-living fungivorous ancestors. However, the exact evolutionary process of these parasites is unclear. Here, we sequenced the genome sequence of a migratory plant nematode,Ditylenchus destructor. We performed comparative genomics among the free-living nematode,Caenorhabditis elegansand all the plant nematodes with genome sequences available. We found that, compared withC. elegans, the core developmental control processes underwent heavy reduction, though most signal transduction pathways were conserved. We also foundD. destructorcontained more homologies of the key genes in the above processes than the other plant nematodes. We suggest thatDitylenchusspp. may be an intermediate evolutionary history stage from free-living nematodes that feed on fungi to obligate plant-parasitic nematodes. Based on the facts thatD. destructorcan feed on fungi and has a relatively short life cycle, and that it has similar features to bothC. elegansand sedentary plant-parasitic nematodes from clade 12, we propose it as a new model to study the biology, biocontrol of plant nematodes and the interaction between nematodes and plants.

Theoretically, the sensitivity of the transfer function (TF) method to detect transformer winding deformation is greater in the higher frequency range. Although measurement based on low voltage impulse (LVI) is definitely faster than that based on swept frequency method (SFM), the analyzable frequency band is narrow due to the typical microsecond impulse. The characteristics of the nanosecond impulse in the frequency domain were studied in this paper. A test System based on Nanosecond low voltage impulse was developed to improve the detection sensitivity. A series experiments were carried out on a 5 kV/100 kVA distribution transformer. Measurement results with two different impulses were compared and de-noising methods were studied. Besides, a destructive experiment was carried out on an special laboratory winding to verify the sensitivity of the method.

Currently, kernel-based methods have drawn much attention from the field of pattern recognition as well as radar target recognition. As we all know, kernel discriminant analysis (KDA) is proved that it is a very effective tool used for dimensionality reduction and feature extraction. However, KDA also suffers from the so-called small sample size problem (SSS) which often exists in high-dimensional pattern recognition data. In order to deal with this problem, a complete KDA called kernel complete discriminant analysis (KCDA) is proposed. The new algorithm views the optimal discriminant vectors as a global transform in the feature space, and which carries out feature extraction by making full use of the discriminative information in both null space and non-null space of the within-class scatter matrix. Thus it makes KCDA a more powerful dicriminator. Experiments based on the measured airplanes database are conducted to evaluate the effectiveness of the proposed method, and the results show that it can achieve better classification performance.

Generalized discriminant analysis (GDA) is a nonlinear extension of the classical linear discriminant analysis (LDA) via kernel trick. As a feature extraction method, it has been proven successful in many applications such as radar high-range-resolution profiles (HRRP) recognition. However, GDA often suffers from the so-called small sample size problem (SSS) which exists in high-dimensional pattern recognition data. To overcome this weakness, we present a new algorithm for solving GDA by utilizing the idea of direct-LDA (DLDA) in this paper. Experiments based on three measured airplanes data are conducted to evaluate the effectiveness of the proposed method. From the results we can see that the new algorithm is more transparent and easier to be implemented than the traditional one, while keeping competitive classification accuracy.

Independent component analysis (ICA) is a statistical method developed from the separation of blind signal, and now it has been successfully used in many fields. In this paper, we present an effective technique combined with a modified FastICA (M-FastICA) algorithm plus genetic algorithms (GAs) for radar high-resolution range profiles (HRRPs) feature extraction. As we all know that the most time-consuming course in FastICA is to compute the Jacobian matrix. So in this modified version, several iterations of FastICA are merged into one iteration but only needs to compute the Jacobian matrix once time. Thereby the convergence velocity of FastICA is accelerated while the performance is not degraded. To demonstrate the above feature extraction algorithm, the classification experiment on three types of radar targets are evaluated. First M-FastICA is applied to extract the independent components from the HRRPs. Then GAs is used to select the optimal basis vectors and thus build a feature subspace. The results show that the introduced method can achieve better classification performance than both PCA and ICA.

To explore the relationship between the alteration in gamma-glutamyl transpeptidase (GGT) mRNA expression and the development of hepatocellular carcinoma (HCC).Three GGT mRNA types (A, B, C) in normal liver tissue, diseased liver tissue without HCC, cancerous and noncancerous tissues from livers with HCC, noncancerous tissues from livers with metastatic tumor and peripheral blood of all the cases were tested by using RT-PCR.In normal livers, the main type of GGT mRNA was type A. In cases with liver diseases but not HCC, the proportion of the types of GGT mRNA was nearly the same as that in normal livers. The proportion of type B was significantly higher in both the cancerous and noncancerous tissues of livers with HCC than in livers without HCC (P0.05). The expression of type A in cancerous tissue was significantly lower than that in the tissue of livers without HCC (P0.05). Among the 26 cases with HCC, GGT mRNA-B was found in the peripheral blood of 12. In 10 HCC cases with negative AFP, GGT mRNA-B was found in the peripheral blood of 5.GGT mRNA expression in the human liver might shift from type A to type B during the development of HCC. Fragment analysis of GGT genes might be a sensitive assay to monitor the cancerous change of hepatic cell.

An expression describing the entropy production in the Burnett equations is constructed from the classical thermodynamic theory using the continuum conservation relations for mass, momentum and energy in conjunction with Gibbs equation in both oneand three-dimensions. The entropy production is transformed into a polynomial in Mach number and Knudsen number which is employed to analyze the thermodynamic properties of both expanding and compressed gases. Each term in the entropy production polynomial in three-dimensions is studied separately due to the complexity of the polynomial expression in three-dimensions. The results indicate that the irreversible entropy production in conventional Burnett equations, augmented Burnett equations and simplified conventional Burnett equations is not positive semi-definite for an expanding but is positive semi-definite for a gas under compression. Thus these equations may violate the second law of thermodynamics in a flow undergoing both compression and expansion. This result may explain the numerical instability encountered in the numerical solution of the Burnett equations.