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The magnetic property measurementfor grain oriented (GO) silicon steel sheet under non-sinusoidal excitations (DC bias and harmonic) were conducted based on the experimental platform. Based on the Preisach model, the static hysteresis and loss properties were accurately simulated. Furthermore, an improved loss model was proposed by adjusting the statistical parameter of abnormal loss, which depends on the characteristic quantities of DC bias or harmonic excitations. The simulated dynamic hysteresis loops and iron losses under different non-sinusoidal conditions were compared with the measured ones, and thus the accuracy and generality of the improved model proposed in this paper were verified. In addition, the influences of the harmonic and DC-biasing quantities upon the total losses is investigated.

The two-dimensional hysteresis property of the soft magnetic composite (SMC) material under circular rotational excitation was measured by the experimental platform. The first-order reversal curves and the corresponding scalar Everett functions can be numerically generated by the measured major hysteresis loops along the orthogonal easy axis and hard axis. Different from the classical model, an improved vector Preisach hysteresis model that considers the anisotropic property of the SMC materials under vector magnetic excitation was put forward by introducing two parameters w and z . The two parameters were used to identify the vector Everett functions and adjust the shape of hysteresis curves under different magnitudes of the magnetic flux density. Furthermore, an efficient hybrid algorithm that combines simulated annealing with Nelder–Mead simplex technique was proposed for the accurate extraction of optimal parameters. The simulated results based on the improved model agree well with the measured ones; thus, the effectiveness and accuracy of the proposed method were verified.

In insects, 20-hydroxyecdysone (20E) limits the growth period by triggering developmental transitions; 20E also modulates the growth rate by antagonizing insulin/insulin-like growth factor signaling (IIS). Previous work has shown that 20E cross-talks with IIS, but the underlying molecular mechanisms are not fully understood. Here we found that, in both the silkworm Bombyx mori and the fruit fly Drosophila melanogaster, 20E antagonized IIS through the AMP-activated protein kinase (AMPK)-protein phosphatase 2A (PP2A) axis in the fat body and suppressed the growth rate. During Bombyx larval molt or Drosophila pupariation, high levels of 20E activate AMPK, a molecular sensor that maintains energy homeostasis in the insect fat body. In turn, AMPK activates PP2A, which further dephosphorylates insulin receptor and protein kinase B (AKT), thus inhibiting IIS. Activation of the AMPK-PP2A axis and inhibition of IIS in the Drosophila fat body reduced food consumption, resulting in the restriction of growth rate and body weight. Overall, our study revealed an important mechanism by which 20E antagonizes IIS in the insect fat body to restrict the larval growth rate, thereby expanding our understanding of the comprehensive regulatory mechanisms of final body size in animals.

On the basis of the TEAM problem 21 benchmark model, a modelling method to predict stray-field loss under real working conditions is presented and validated to investigate the influence of harmonic excitation on stray-field loss of shielding structural components of converter transformers in high-voltage direct current systematically. An improved method is adapted to determine stray-field loss of magnetic and non-magnetic component based on the experimental measurement and numerical simulation. An experimental platform is established to measure magnetic properties and loss characteristics of the grain-oriented silicon steel sheets, aiming at parameter identification and verification of the loss modelling applicable for laminated sheets under harmonic magnetisation. Meanwhile, the additional iron loss caused by perpendicular flux penetration is obtained by special treatment of material properties and analysed to observe its contribution to the stray-field loss under three-dimensional harmonic magnetisation. Field and loss comparison between measurement and simulation verifies the validation of the proposed modelling method.

Insects have evolved numerous adaptations and colonized diverse terrestrial environments. Several polyneopterans, including dictyopterans (cockroaches and mantids) and locusts, have developed oothecae, but little is known about the molecular mechanism, physiological function, and evolutionary significance of ootheca formation. Here, we demonstrate that the cockroach asymmetric colleterial glands produce vitellogenins, proline-rich protein, and glycine-rich protein as major ootheca structural proteins (OSPs) that undergo sclerotization and melanization for ootheca formation through the cooperative protocatechuic acid pathway and dopachrome and dopaminechrome subpathway. Functionally, OSP sclerotization and melanization prevent eggs from losing water at warm and dry conditions, and thus effectively maintain embryo viability. Dictyopterans and locusts convergently evolved vitellogenins, apolipoprotein D, and laminins as OSPs, whereas within Dictyoptera, cockroaches and mantids independently developed glycine-rich protein and fibroins as OSPs. Highlighting the ecological-evolutionary importance, convergent ootheca formation represents a successful reproductive strategy in Polyneoptera that promoted the radiation and establishment of cockroaches, mantids, and locusts.

Phosphorylation is a key post-translational modification in regulating autophagy in yeast and mammalians, yet it is not fully illustrated in invertebrates such as insects. ULK1/Atg1 is a functionally conserved serine/threonine protein kinase involved in autophagosome initiation. As a result of alternative splicing, Atg1 in the silkworm, Bombyx mori, is present as three mRNA isoforms, with BmAtg1c showing the highest expression levels. Here, we found that BmAtg1c mRNA expression, BmAtg1c protein expression and phosphorylation, and autophagy simultaneously peaked in the fat body during larval-pupal metamorphosis. Importantly, two BmAtg1c phosphorylation sites were identified at Ser269 and Ser270, which were activated by BmAMPK, the major energy-sensing kinase, upon stimulation with 20-hydroxyecdysone and starvation; additionally, these Atg1 phosphorylation sites are evolutionarily conserved in insects. The two BmAMPK-activated phosphorylation sites in BmAtg1c were found to be required for BmAMPK-induced autophagy. Moreover, the two corresponding DmAtg1 phosphorylation sites in the fruit fly, Drosophila melanogaster, are functionally conserved for autophagy induction. In conclusion, AMPK-activated Atg1 phosphorylation is indispensable for autophagy induction and evolutionarily conserved in insects, shedding light on how various groups of organisms differentially regulate ULK1/Atg1 phosphorylation for autophagy induction.

Based on two Everett functions, a method for identifying asymmetric hysteresis loops is proposed. Besides, the statistical parameter $V_{\mathrm{0}}$ is extracted from the excess loss under single-frequency sinusoidal and DC hybrid excitation. The extracted $V_{\mathrm{0}}$ are used by neural network algorithm to fit the $V_{\mathrm{0}}$ suitable for complex excitation. An improved calculation method of excess loss is used to calculate the iron loss of grain oriented silicon steel sheet. Combined with Preisach model and eddy loss calculation formula, the hysteresis and loss characteristics of grain oriented silicon steel sheet under AC-DC hybrid excitation are predicted. The predicted dynamic hysteresis loops and losses under various working conditions are compared with the measured ones, which verifies the accuracy and generality of the improved method proposed in this paper.

Thitarodes (Lepidoptera, Hepialidae) is the only genus that hosts to the Ophiocordyceps sinensis, a traditional Chinese medicine considered as a powerful medicinal supplement. In this study, the complete mitochondrial genomes (mitogenomes) of two species, T. damxungensis and T. pui, have been sequenced, which are 15,928 bp and 15,362 bp in size respectively, and both contain 13 protein-coding genes (PCGs), 2 rRNAs, 22 tRNAs and an AT-rich region. Like other hepialoids, the gene arrangement of the mitogenomes of T. damxungensis and T. pui is identical to the ancestral arrangement but differs from those of other lepidopteran species on account of the different arrangements of trnM, trnI, and trnQ. The size of AT-rich region is 545 bp in T. damxungensis and 1030 bp in T. pui. Tandem repetition in the AT-rich region is responsible for the length difference of the A + T-rich region in both species. In Hepialidae, the phylogenetic study based on the dataset of the sequences that combined the protein-coding genes and RNA genes suggested that the species T. yunnanensis should still belong to the genus Thitarodes rather than Ahamns, which is different from the results based on the traditional phylogeny.

In this study, the crash-worthiness of a regular Centurion 2M barrier, which is a type of portable water-filled barrier (PWFB), is evaluated under different collision conditions. A numerical model of the regular Centurion 2M barrier, consisting of a plastic shell and water, was developed and validated. The validity of the numerical model is demonstrated by comparisons to experimental results. During the establishment of the finite element numerical model, the ALE (Arbitrary Lagrange-Euler) method was used to solve the problem of the fluid-structure interaction of the PWFB system. This model can be extended to a series of impact cases including an actual pick-up truck. Impact cases set six collision conditions according to different collision speeds and angles. The dynamic response of the collision between the pick-up truck and the PWFB process was investigated. From the analysis, we find that the greater the collision angle is, the greater the impact is on the collision result. According to the actual accident collision angle, setting the collision angle above 50° is satisfactory in most situations. In addition, a regular Centurion 2M barrier is just suitable for use on roads when the speed of vehicles is 20 km/h or less.

An experiment for measuring two-dimensional (2-D) magnetic properties of soft magnetic composite (SMC) materials is carried out by using a measuring system of vector magnetic property. Based on the measured scalar major hysteresis curves, parameter identification of vector hysteresis model is achieved through construction of vector Everett function from numerically generated first order reversal curves (FORCs). In comparison with the classical isotropic vector model, the proposed model introduces two parameters which are controlled by magnitude of magnetic flux density, aiming at consideration of anisotropic property of SMC. Moreover, a robust and efficient hybrid algorithm that combines simulated annealing (SA) with the Nelder-Mead Simplex (NMS) technique is proposed for optimal parameters identification and higher accuracy. Simulated results by the improved model agree well with the measured ones, which verifies the effectiveness and accuracy of the proposed method.

Many cockroach species have adapted to urban environments, and some have been serious pests of public health in the tropics and subtropics. Here, we present the 3.38-Gb genome and a consensus gene set of the American cockroach, Periplaneta americana. We report insights from both genomic and functional investigations into the underlying basis of its adaptation to urban environments and developmental plasticity. In comparison with other insects, expansions of gene families in P. americana exist for most core gene families likely associated with environmental adaptation, such as chemoreception and detoxification. Multiple pathways regulating metamorphic development are well conserved, and RNAi experiments inform on key roles of 20-hydroxyecdysone, juvenile hormone, insulin, and decapentaplegic signals in regulating plasticity. Our analyses reveal a high level of sequence identity in genes between the American cockroach and two termite species, advancing it as a valuable model to study the evolutionary relationships between cockroaches and termites., The American cockroach (Periplaneta americana) is an hemimetabolous insect with rapid growth, high fecundity, and remarkable tissue-regeneration capability. Here Li et al sequence its 3.38-Gb genome and perform the functional studies, yielding insights into its environmental adaptation and developmental plasticity.

Recently, parainfluenza virus 5 (PIV5) infection has been increasingly reported in mammals. In this study, five PIV5 strains were isolated from diarrhea-affected piglets from four provinces or municipalities in China. An F-gene-based phylogenetic tree indicated that the five isolated strains were closely related to the PIV5 strain ZJQ-221 from a lesser panda in China, and the PIV5 strain 1168-1 from a dog in South Korea. The new isolates differed genetically from other pig, calf, rhesus macaque kidney cells, human, and dog PIV5 reference strains. Our study reveals the presence of PIV5 in intestinal tissue samples collected from diarrhea-affected piglets, and provides novel information regarding the epidemiology and tissue tropism of PIV5.

To trace the prevalence of canine distemper virus (CDV) in diarrhoetic dogs, a total of 201 stool samples were collected in the Heilongjiang province of northeastern China from May 2014 to April 2015. The 201 fecal samples were subjected to the detection of CDV by using RT-PCR targeting the partial N gene, phylogenetic analysis based on the complete H gene, and co-infection analysis. Results indicated that 24.88% (50/201) of the samples were positive for CDV. The fifty CDV samples exhibited an overall co-infection rate of 94% (47/50) with four enteric viruses (82%, 41/50) and five bacteria (72%, 36/50). The positivity rate of CDV exhibited differences among regions, seasons, ages and immunization status. Phylogenetic analysis of the complete H genes (n=6) revealed that the CDV strains identified in our study belonged to the Asia-1 group, and showed genetic diversities. These data provide evidence that there are a number of genetically diverse CDV Asia-1 strains circulating in diarrhoetic dogs in northeastern China; the CDV-affected animals exhibit the high co-infection with other enteric viruses and bacteria.

Porcine epidemic diarrhoea virus (PEDV) is an emerging and re‐emerging epizootic virus of swine that causes substantial economic losses to the pig industry in China and other countries. The variations in the virus, and its co‐infections with other enteric viruses, have contributed to the poor control of PEDV infection. In the current study, a broad epidemiological investigation of PEDV was carried out in 22 provinces or municipalities of China during 2015–2018. The enteric viruses causing co‐infection with PEDV and the genetic diversity of the PEDV S1 gene were also analysed. The results indicated that, of the 543 diarrhoea samples, 66.85% (363/543) were positive for PEDV, and co‐infection rates of PEDV with 13 enteric viruses ranged from 3.58% (13/363) to 81.55% (296/363). Among these enteric viruses, the signs of diarrhoea induced by PEDV were potentially associated with co‐infections with porcine enterovirus 9/10 (PEV) and torque teno sus virus 2 (TTSuV‐2) (p

In this paper, in view of the low efficiency of the traditional finite element method (FEM), which has been widely used in the insulation design of power transformers, the response surface methodology (RSM) is proposed to optimize the insulation structure of a power transformer electrostatic ring. Firstly, the power transformer model was built using the ANSYS parametric design language (APDL) to realize the automatic pre-processing of numerical calculation. Then with the objective of reducing the maximum electric field intensity, the Taguchi method was used to select the parameters that have a greater impact on the maximum electric field intensity, by which the subsequent optimization process could be effectively simplified. The test points were constructed by the central composite design (CCD) and a response surface model was established by the mutual calls of MATLAB and ANSYS. Finally, the variance analysis, diagnostic analysis, and significance test of regression were carried out to obtain the final response surface model. By comparing the result of RSM with that of FEM, we can find that the results obtained by the two methods are consistent and the maximum electric field strength is obviously reduced. The RSM is more systematic and convincing, which improves the optimization efficiency and provides a reliable and fast way for the optimization of power transformers.

Cholesterol plays essential roles in animal development and disease progression. Here, we characterize the evolutionary pattern of the canonical cholesterol biosynthesis pathway (CBP) in the animal kingdom using both genome-wide analyses and functional experiments. CBP genes in the basal metazoans were inherited from their last common eukaryotic ancestor and evolutionarily conserved for cholesterol biosynthesis. The genomes of both the basal metazoans and deuterostomes retain almost the full set of CBP genes, while Cnidaria and many protostomes have independently experienced multiple massive losses of CBP genes that might be due to the geologic events during the Ediacaran period, such as the appearance of an exogenous sterol supply and the frequent perturbation of ocean oxygenation. Meanwhile, the indispensable utilization processes of cholesterol potentially strengthened the maintenance of the complete set of CBP genes in vertebrates. These results strengthen both biotic and abiotic roles in the macroevolution of a biosynthesis pathway in animals.

In order to study the coupling fluid and thermal problems of the local winding in oil-immersed power transformers, the least-squares finite element method (LSFEM) and upwind finite element method (UFEM) are adopted, respectively, to calculate the fluid and thermal field in the oil duct. When solving the coupling problem by sequential iterations, the effect of temperature on the material property and the loss density of the windings should be taken into account. In order to improve the computation efficiency for the coupling fields, an algorithm, which adopts two techniques, the dimensionless LSFEM and the combination of Jacobi preconditioned conjugate gradient method (JPCGM) and the two-side equilibration method (TSEM), is proposed in this paper. To validate the efficiency of the proposed algorithm, a local winding model of a transformer is built and the fluid field is computed by the conventional LSFEM, dimensionless LSFEM, and the Fluent software. While the fluid and thermal computation results of the local winding model of a transformer obtained by the two LSFEMs are basically consistent with those of the Fluent software, the stiffness matrix, which is formed by the dimensionless scheme of LSFEM and preconditioned by the JPCGM and TSEM, has a smaller condition number and a faster convergence rate of the equations. Thus, it demonstrates a broader applicability.

Pasteurella multocida, a Gram-negative nonmotile coccobacillus, is the causative agent of fowl cholera, bovine hemorrhagic septicemia, enzoonotic pneumonia and swine atropic rhinitis. Two filamentous hemagglutinin genes, fhaB1 and fhaB2, are the potential virulence factors. In this study, an inactivation fhaB1 mutant of P. multocida in avian strain C48-102 was constructed by a kanamycin-resistance cassette. The virulence of the fhaB1 mutant and the wild type strain was assessed in chickens by intranasal and intramuscular challenge. The inactivation of fhaB1 resulted in a high degree of attenuation when the chickens were challenged intranasally and a lesser degree when challenged intramuscularly. The fhaB1 mutant and the wild type strain were investigated their sensitivity to the antibody-dependent classical complement-mediated killing pathway in 90% convalescent chicken serum. The fhaB1 mutant was serum sensitive as the viability has reduced between untreated serum and heat inactivated chicken serum (P

Rabbit hemorrhagic disease virus (RHDV) causes haemagglutination and severe liver damage, with a high mortality rate. To develop a rapid and sensitive method for the surveillance of RHDV, a one-step reverse transcription-loop-mediated isothermal amplification (RT-LAMP) assay was established using a set of four primers specific for the VP60 gene segment of RHDV. The established assay was performed at 64°C for 40 min under isothermal conditions, and the results were visualized directly by electrophoresis or as fluorescent signals under ultraviolet light. The detection limit of the RT-LAMP assay was 10 copies of viral RNA per reaction, which was comparable to quantitative real-time RT-PCR, and 100-fold more sensitive than standard RT-PCR. Furthermore, seven viral RNAs of field isolates in China could be detected successfully using this assay. Overall, the newly established RT-LAMP assay indicates the potential usefulness of the technique as a simple, rapid and sensitive procedure, and can visually detect RHDV infection without the need for any specialized equipment.

Group A rotaviruses (RVAs) are major pathogens associated with acute gastroenteritis in young children and in a wide variety of domestic animals. The full-length genome of a rabbit RVA strain, RVA/Rabbit-tc/CHN/N5/1992/G3P[14], showed a G3-P[14]-I17-R3-C3-M3-A9-N1-T1-E3-H2 genomic configuration. A novel VP6 genotype, I17, was confirmed by the Rotavirus Classification Working Group. Phylogenetic analyses revealed that strain N5 possessed VP1–3, VP7, NSP1–2 and NSP4 genes closely related to those of the simian strain TUCH, NSP3 and NSP5 genes closely related to the human strains Wa and 69M, and a VP4 gene closely related to the rabbit strain 30/96 and sheep strain OVR762. The RRV and TUCH shared their ancestry with canine/feline RVAs and showed a close relationship to the human T152/feline-like RVAs. Comparison with the genotypes of the simian strains TUCH and RRV, canine strains A79-10, CU-1, K9, feline strains Cat2 and Cat97, and human strains T152 and 69M showed that RVA/Rabbit-tc/CHN/N5/1992/G3P[14] was possibly of feline/canine origin, or was a multiple reassortment involving canine, feline and human rotaviruses. The sequencing and phylogenetic analyses of rotavirus genomes is critical to the elucidation of the patterns of virus evolution.

Pasteurella multocida, a Gram-negative nonmotile coccobacillus, is the causative agent of fowl cholera in poultry, hemorrhagic septicemia in cattle, atropic rhinitis in swine, and snuffles in rabbits. The differentially expressed gene profile of P. multocida in infected rabbit livers was identified and compared with that from in vitro culture by selective capture of transcribed sequences. A total of 31 genes were identified, of which 28 encoded enzymes for amino acid biosynthesis and metabolism, intermediary metabolism, and energy metabolism, or proteins for regulatory adaptive responses, general microbial stress response, transport proteins, and secreted proteinases. Three were unknown, novel genes. Five genes representing different categories were chosen randomly and verified by real-time reverse transcriptase-polymerase chain reaction analysis. All were upregulated by P. multocida in infected rabbit livers, with changes ranging from 1.61- to 13.55-fold when compared with in vitro cultures. This study has identified genes of P. multocida that are upregulated during infection of rabbit livers when compared with in vitro growth conditions. The genes will provide a molecular basis for further study of the pathogenesis of P. multocida.

We constructed Pasteurella multocida strain C51-17 aroA mutant and characterized its virulence.Suicide recombinant plasmid of pBC-aroA-Tn903 was constructed with kanamycin gene and transformed into Pasteurella multocida by electroporation. aroA mutant strain of P. multocida was screened by kanamycin resistance and chloromycetin sensitivity and identified by PCR. Virulence of aroA mutant strain was tested in mice by intraperitoneal injection.The aroA mutant strain of P. multocida C51-17 was successfully constructed. Growth rate of aroA mutant strain was slower within the first 6 hour and similar to the wild-type strain in vitro. The virulence test indicated that aroA mutant strain was significant attenuated and no death was found in mice even inoculated at a dosage of 1.0 x 10(6) CFU.The virulence of aroA mutant strain of P. multocida was highly attenuated in mice. The results of this study will contribute to a better understanding of pathogenesis of P. multocida.

Rabbit hemorrhagic disease (RHD) is a contagious disease in adult rabbits, with high mortality, that occurs throughout the world. The VP60 protein has been implicated as main protein antigen in virus diagnosis and vaccine design. In this report, we describe the construction of a novel DNA vaccine (pcDNA-VP60) expressing the RHDV capsid protein (VP60), and the expression of the recombinant protein was identified through indirect immunofluorescence assay (IFA) and Western blot assay. VP60 protein self-assembled to form virus-like particles (VLPs) observed by electron microscopy were morphologically similar to native virions. For the evaluation of vaccine efficacy, rabbits were inoculated with PBS, pcDNA3.1 (+) , pcDNA-VP60 or RHDV inactive vaccine. They were challenged with RHDV-TP isolate four weeks after last boost immunization. In all cases, the rabbits immunized with pcDNA-VP60 developed high level of RHDV-specific antibodies and cellular immune response. The rabbits injected with DNA vaccine were completely protected against RHDV challenge like commercial RHDV inactive vaccine, moreover, RHDV viral load was significantly reduced in the liver samples from immunized rabbits. The recombinant DNA vaccine may provide a novel strategy for the immunization of rabbits for the control of RHDV.