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The necrotrophic pathogen Sclerotinia sclerotiorum is one of the most damaging and economically important plant pathogens. Pydiflumetofen, which was developed by Syngenta Crop Protection, has already been registered in China for the management of Sclerotinia stem rot, which was caused by S. sclerotiorum in oilseed rape. In an attempt to preempt and forestall the development of resistance to this useful fungicide, the current study was initiated to investigate the potential mechanism of resistance in laboratory mutants. Five pydiflumetofen-resistant S. sclerotiorum mutants were successfully generated by repeated exposure to the fungicide under laboratory conditions. Although the mutants had greatly reduced sensitivity to pydiflumetofen, they were also found to have significantly (P < 0.05) reduced fitness, exhibiting reduced mycelial growth and sclerotia formation on potato dextrose agar medium. However, three of the four mutants had significantly (P < 0.05) increased pathogenicity on detached soybean leaves compared with their respective parental isolates, indicating a moderate to high level of fungicide resistance risk according to the criteria of the Fungicide Resistance Action Committee. Sequence analysis of four succinate dehydrogenase (Sdh) target genes identified several nucleotide changes in the sequences of the pydiflumetofen-resistant mutants, most of which were synonymous and caused no changes to the predicted amino acid sequences. However, all of the pydiflumetofen-resistant mutants had two amino acid point mutations (A11V and V162A) in their predicted SsSdhB sequence. No similar changes were found in the SsSdhA, SsSdhC, and SsSdhD genes of any of the mutants tested. In addition, there was a positive cross-resistance between pydiflumetofen and boscalid, and no cross-resistance between pydiflumetofen and other commonly used fungicides, including tebuconazole, fludioxonil, cyprodinil, dimethachlone, prochloraz, pyraclostrobin, fluazinam, procymidone, and carbendazim. These results indicate that pydiflumetofen has great potential as an alternative fungicide for the control of S. sclerotiorum, especially where resistance to other fungicides has already emerged. Mixing or alternate application with fludioxonil, prochloraz, and fluazinam could be used to limit the risk of resistance to pydiflumetofen.

Sclerotinia sclerotiorum is one of the most damaging and economically important necrotrophic plant pathogens, infecting more than 400 plant species globally. Although the phenylpyrrole fungicide fludioxonil has high activity against S. sclerotiorum, reports indicate that there is also substantial potential for the development of fungicide resistance. However, the current study investigating five fludioxonil-resistant laboratory mutants found a significant fitness cost associated with fludioxonil resistance resulting in significantly (P < 0.05) reduced mycelial growth and sclerotia formation on potato dextrose agar as well as significantly (P < 0.05) lower pathogenicity on detached tomato leaves, with one mutant, LK-1R, completely losing the capacity to cause infection. In addition, all of the fludioxonil-resistant mutants had significantly (P < 0.05) increased sensitivity to osmotic stress (0.5 M of potassium chloride and 1.0 M of glucose), which is consistent with the proposed fludioxonil target sites within the high osmolarity glycerol stress response mitogen-activated protein kinase (HOG1-MAPK) signaling transduction pathway. Sequence analysis of six genes from this two-component pathway, including SsHk, SsYpd, SsSk1, SsSk2, SsPbs, and SsHog, revealed several mutations that may be associated with fludioxonil resistance. For example, six separate point mutations were found in SsHk that led to changes in the predicted amino acid sequence, including A136G, F249V, G353A, E560K, M610K, and K727R. Similarly, SsPbs had three mutations (D34G, S46L, and L337E), SsSk1 and SsYpd had two (S53G and A795V for SsSk1, and E67G and Y141H for SsYpd), and SsHog and SsSk2 had one each (V220A and S763P, respectively). To our knowledge, these constitute the first reports of amino acid changes in proteins of the HOG1-MAPK pathway being associated with fludioxonil resistance in S. sclerotiorum. This study also showed a positive cross-resistance between fludioxonil and dimethachlone and procymidone, but none with tebuconazole or carbendazim, indicating that the inclusion of tebuconazole within an integrated pest management program could reduce the risk of fludioxonil resistance developing in field populations of S. sclerotiorum and ensure the sustainable production of soybeans in China into the future.

The ankyrin-transmembrane (ANKTM) subfamily is the most abundant subgroup of the ANK superfamily, with critical roles in pathogen defense. However, the function of ANKTM proteins in wheat immunity remains largely unexplored. Here, a total of 381 ANKTMs were identified from five Triticeae species and Arabidopsis, constituting five classes. Among them, class a only contains proteins from Triticeae species and the number of ANKTM in class a of wheat is significantly larger than expected, even after consideration of the ploidy level. Tandem duplication analysis of ANKTM indicates that Triticum urartu, Triticum dicoccoides and wheat all had experienced tandem duplication events which in wheat-produced ANKTM genes all clustered in class a. The above suggests that not only did the genome polyploidization result in the increase of ANKTM gene number, but that tandem duplication is also a mechanism for the expansion of this subfamily. Micro-collinearity analysis of Triticeae ANKTMs indicates that some ANKTM type genes evolved into other types of ANKs in the evolution process. Public RNA-seq data showed that most of the genes in class d and class e are expressed, and some of them show differential responses to biotic stresses. Furthermore, qRT-PCR results showed that some ANKTMs in class d and class e responded to powdery mildew. Silencing of TaANKTM2A-5 by barley stripe mosaic virus-induced gene silencing compromised powdery mildew resistance in common wheat Bainongaikang58. Findings in this study not only help to understand the evolutionary process of ANKTM genes, but also form the basis for exploring disease resistance genes in the ANKTM gene family.

Leaves are the key organs of plants that produce photosynthates. Leaf senescence aids nutrient remobilization from source to sink tissues, which dramatically affects crop quality and yield. Although several senescence-associated genes (SAGs) have been recognized in cotton, the function of lipoic acid synthase in leaf senescence remains unclear. Therefore, we isolated a lipoic acid synthase gene named GhLIP1 from cotton (Gossypium hirsutum L.). Protein domain analysis revealed that GhLIP1 had a LIAS-N domain and an Elp3 domain, and yeast mutant complementation experiments demonstrated that GhLIP1 was a lipoic acid synthase. GhLIP1 expression pattern analysis showed that GhLIP1 was vastly expressed in fibres, and the phytohormone IAA (indole-3-acetic acid) induced its transcription. When GhLIP1 was transformed into Arabidopsis, the leaves of overexpression Arabidopsis exhibited a late leaf senescence phenotype compared to wild-type Arabidopsis, Col-0. Moreover, downregulation of GhLIP1 expression using virus-induced gene silencing (VIGS) technology resulted in early leaf senescence in cotton. qRT-PCR analyses revealed that two SAGs, GhWRKY53 and GhNAP, were upregulated in cotton plants with GhLIP1 knock-down. Cell ultrastructure observations found that chloroplasts were degraded in an orderly manner in cotton leaf cells with GhLIP1 knock-down. These results suggest that GhLIP1 plays a significant role in leaf senescence in cotton.

Background: Hypoxic pulmonary hypertension (HPH) is a challenging lung arterial disorder with remarkably high incidence and mortality, and so far patients have failed to benefit from therapeutics clinically available. Max interacting protein 1–0 (Mxi1-0) is one of the functional isoforms of Mxi1. Although it also binds to Max, Mxi1-0, unlike other Mxi1 isoforms, cannot antagonize the oncoprotein c-Myc because of its unique proline rich domain (PRD). While Mxi1-0 was reported to promote cell proliferation via largely uncharacterized mechanisms, it is unknown whether and how it plays a role in the pathogenesis of HPH.Methods: GEO database was used to screen for genes involved in HPH development, and the candidate players were validated through examination of gene expression in clinical HPH specimens. The effect of candidate gene knockdown or overexpression on cultured pulmonary arterial cells, e.g., pulmonary arterial smooth muscle cells (PASMCs), was then investigated. The signal pathway(s) underlying the regulatory role of the candidate gene in HPH pathogenesis was probed, and the outcome of targeting the aforementioned signaling was evaluated using an HPH rat model.Results: Mxi1 was significantly upregulated in the PASMCs of HPH patients. As the main effector isoform responding to hypoxia, Mxi1-0 functions in HPH to promote PASMCs proliferation. Mechanistically, Mxi1-0 improved the expression of the proto-oncogene c-Myc via activation of the MEK/ERK pathway. Consistently, both a MEK inhibitor, PD98059, and a c-Myc inhibitor, 10058F4, could counteract Mxi1-0-induced PASMCs proliferation. In addition, targeting the MEK/ERK signaling significantly suppressed the development of HPH in rats.Conclusion: Mxi1-0 potentiates HPH pathogenesis through MEK/ERK/c-Myc-mediated proliferation of PASMCs, suggesting its applicability in targeted treatment and prognostic assessment of clinical HPH.

Fusarium graminearum is the primary causal agent of Fusarium head blight (FHB) of wheat. The phenylpyrrole fungicide fludioxonil is not currently registered for the management of FHB in China. The current study assessed the fludioxonil sensitivity of a total of 53 F. graminearum isolates collected from the six most important wheat-growing provinces of China during 2018 and 2019. The baseline fludioxonil sensitivity distribution indicated that all of the isolates were sensitive, exhibiting a unimodal cure with a mean effective concentration for 50% inhibition value of 0.13 ± 0.12 μg/ml (standard deviation). Five fludioxonil-resistant mutants were subsequently induced by exposure to fludioxonil under laboratory conditions. Ten successive rounds of subculture in the absence of the selection pressure indicated that the mutation was stably inherited. However, the fludioxonil-resistant mutants were found to have reduced pathogenicity, higher glycerol accumulation, and higher osmotic sensitivity than the parental wild-type isolates, indicating that there was a fitness cost associated with fludioxonil resistance. In addition, the study also found a positive cross resistance between fludioxonil, procymidone, and iprodione, but not with other fungicides such as boscalid, carbendazim, tebuconazole, and fluazinam. Sequence analysis of four candidate target genes (FgOs1, FgOs2, FgOs4, and FgOs5) revealed that the HBXT2R mutant contained two point mutations that resulted in amino acid changes at K223T and K415R in its FgOs1 protein, and one point mutation at residue 520 of its FgOs5 protein that resulted in a premature stop codon. Similarly, the three other mutants contained point mutations that resulted in changes at the K192R, K293R, and K411R residues of the FgOs5 protein but none in the FgOs2 and FgOs4 genes. However, it is important to point out that the FgOs2 and FgOs4 expression of all the fludioxonil-resistant mutants was significantly (P < 0.05) downregulated compared with the sensitive isolates (except for the SQ1-2 isolate). It was also found that one of the resistant mutants did not have changes in any of the sequenced target genes, indicating that an alternative mechanism could also lead to fludioxonil resistance.

Background Virus-induced gene silencing (VIGS) is one of the most convenient and powerful methods of reverse genetics. In vitro-inoculation of plant virus is an important method for studying the interactions between viruses and plants. Agrobacterium-based infiltration has been widely adopted as a tool for VIGS and in vitro-inoculation of plant virus. Most agrobacterium-based infiltration methods applied to VIGS and virus inoculation have the characteristics of low transformation efficiencies, long plant growth time, large amounts of plant tissue, large test spaces, and complex preparation procedures. Therefore, a rapid, simple, economical, and highly efficient VIGS and virus inoculation method is in need. Previous studies have shown that the selection of suitable plant tissues and inoculation sites is the key to successful infection. Results In this study, Tobacco rattle virus (TRV) mediated VIGS and Tomato yellow leaf curl virus (TYLCV) for virus inoculation were developed in tomato plants based on the agrobacterium tumefaciens-based infiltration by injection of the no-apical-bud stem section (INABS). The no-apical-bud stem section had a “Y- type” asymmetric structure and contained an axillary bud that was about 1–3 cm in length. This protocol provides high transformation (56.7%) and inoculation efficiency (68.3%), which generates VIGS transformants or diseased plants in a very short period (8 dpi). Moreover, it greatly reduces the required experimental space. This method will facilitate functional genomic studies and large-scale disease resistance screening. Conclusions Overall, a rapid, simple, and highly efficient method for VIGS and virus inoculation by INABS was developed in tomato. It was reasonable to believe that it can be used as a reference for the other virus inoculation methods and for the application of VIGS to other crops (such as sweet potato, potato, cassava and tobacco) that develop axillary buds and can survive from cuttings.

Background The commonly used NEMA IEC Body phantom has a number of defects, hindering its application for detecting micro-lesions and measuring the performance parameters of computed tomography (CT). This study aimed to propose a PET/CT phantom designed by National Institute of Metrology (NIM), China, which is capable of simultaneously testing the performance of PET and CT systems, and to evaluate the quality of imaging. Methods The phantom developed in the present study, the NIM PET/CT phantom, is composed of a PET imaging module and a CT imaging module, and these modules are connected together through bolts, which can simultaneously measure the imaging performance of PET and CT systems. Hot spheres were filled with 4:1 sphere-to-background activity concentration using 18F-fluorodeoxyglucose (18F-FDG), and cold spheres were filled with non-radioactive water. We compared the results of imaging obtained from the NIM PET/CT phantom and the NEMA IEC Body phantom to assess their diagnostic efficacy. In order to evaluate the generalization ability of the NIM PET/CT phantom, three different PET/CT systems were used to scan on the same scanning protocol. To evaluate the effects of image reconstruction algorithms on image quality assessment, ordered subset expectation maximization (OSEM), OSEM-point-spread function (PSF), OSEM-TOF, and OSEM-PSF-TOF algorithms were employed. Results The imaging quality of the NIM PET/CT phantom and the NEMA IEC Body phantom was relatively consistent. The NIM PET/CT phantom could detect 7 mm spheres without influencing the imaging quality. It was found that PSF reconstruction exhibited to reduce the speed of convergence, the contrast and background variability of spheres (13–28 mm) were significantly improved after two iterations. In addition to improve the image contrast and background variability, TOF could markedly improve the overall image quality and instrument detection limit. TOF-PSF could noticeably reduce noise level, enhance imaging details, and improve quality of imaging. Conclusions The results showed that in comparison with the NEMA IEC Body phantom, the NIM PET/CT phantom outperformed in evaluating the PET image quality of micro-lesions and the performance parameters of CT.

Pomegranate (Punica granatum L.) is an economically important fruit of the Punicaceae family and widely cultivated in the world. In 2019 and 2020, pomegranate fruits showing rot symptoms initiating from seed were observed in different pomegranate-cultivated fields in Henan province of China. Bacteria as a potential pathogen were isolated from the rot tissue of pomegranate seeds, and its pathogenicity was confirmed. The bacterium was identified as Bacillus altitudinis based on morphology and sequence analysis on the 16S ribosomal DNA and the gyrB gene. This is the first report on Bacillus altitudinis causing seed rot of pomegranate.

The gray mold caused by Botrytis cinerea has a significant impact on tomato production throughout the world. Although the synthetic fungicide fludioxonil can effectively control B. cinerea, there have been several reports of resistance to this fungicide. This study indicated that all of the fludioxonil-resistant strains tested, including one field-resistant isolate and four laboratory strains, had reduced fitness relative to sensitive isolates. In addition to having reduced growth, sporulation, and pathogenicity, the resistant strains were more sensitive to osmotic stress and had significantly (P < 0.05) higher peroxidase activity. BOs1, a kinase in the high-osmolarity glycerol stress response signal transduction pathway, is believed to harbor mutations related to fludioxonil resistance. Sequence analysis of their BOs1 sequences indicated that the fludioxonil-resistant field isolate, XXtom1806, had four point mutations resulting in four amino acid changes (I365S, S531G, T565N, and T1267A) and three amino acids (I365S, S531G, and T565N) in the histidine kinases, adenylyl cyclases, methyl-accepting chemotaxis receptors, and phosphatases domain, which associated with fludioxonil binding. Similarly, two of the laboratory strains, XXtom-Lab1 and XXtom-Lab4, had three (Q846S, I1126S, and G415D) and two (P1051S and V1241M) point mutations, respectively. A third strain, XXtom-lab3, had a 52-bp insertion that included a stop codon at amino acid 256. Interestingly, the BOs1 sequence of the fourth laboratory strain, XXtom-lab5, was identical to those of the sensitive isolates, indicating that an alternative resistance mechanism exists. The study also found evidence of positive cross-resistance between fludioxonil and the dicarboximide fungicides procymidone and iprodione, but no cross-resistance was detected with any other fungicides tested, including boscalid, carbendazim, tebuconazole, and fluazinam.

Fusarium head blight (FHB), mainly caused by Fusarium graminearum, has become one of the most serious diseases that damage wheat. The TaPFT (pore-forming toxin-like) and TaHRC (histidine-rich calcium-binding protein) genes at the quantitative trait locus Fhb1 were identified to confer resistance to FHB in the wheat cultivar Sumai 3. In this study, a wheat ricin B-like lectin gene (designated TaRBL) that interacted with TaPFT was isolated by a yeast two-hybrid screen of a wheat cDNA library. A yeast two-hybrid and bimolecular fluorescence complementation study further verified that TaRBL interacted with TaPFT but not with TaHRC. Gene expression studies showed that upon F. graminearum infection, TaRBL expression was upregulated in resistant cultivars but downregulated in susceptible cultivars. Furthermore, knockdown of TaRBL expression by barley stripe mosaic virus-induced gene silencing significantly reduced the resistance of wheat to FHB in both the resistant cultivar Sumai 3 and the susceptible cultivar Jimai 22. Thus, we conclude that TaRBL encodes a ricin B-like lectin protein that interacts with TaPFT and is involved in resistance to FHB in wheat.

Autotoxicity is a serious problem for continuous cropping of cucumber, it can limit its own growth and that of nearby cucumber plants and decrease yield and quality. Cinnamic acid (CA) derivatives are a class of autotoxins that can mimic autotoxic effects in cucumber. We screened an Arabidopsis long hairpin RNA (lhRNA) library under CA-mimicked autotoxicity stress to obtain autotoxicity-resistant mutant lines. The glycerol-3-phosphate 2-O-acyltransferase 6 (GPAT6) gene was found to be silenced in one resistant mutant line, and GPAT6 homologous gene in cucumber was cloned and named CuGPAT6. To test gene function quickly, a new tobacco rattle virus (TRV)-mediated virus-induced gene silencing (VIGS) system was established in cucumber using a special agroinfiltration solution and whole cotyledonary nodes. Cucumber phytoene desaturase gene (CuPDS) and CuGPAT6 gene were successfully silenced with a newly established tobacco rattle virus (TRV)-mediated virus-induced gene silencing (VIGS) system in cucumber showing photobleaching and decreased CuPDS expression in leaves; and silencing of CuGPAT6 enhanced the tolerance to the autotoxin stress mimicked by CA in cucumber. It indicated that the alleviation of the damage caused by CA treatment was probably through maintaining the integrity of cellular structure, supporting cell vitality and promoting growth in roots, and increasing the integrate chloroplast and thylakoid numbers in leaves, which restored the growth and net photosynthesis rate of CA treated CuGPAT6 silenced plants to the similar level to those of control plants. The results also demonstrated that the newly established TRV mediated VIGS system is functional, rapid, convenient and highly efficient in cucumber.

For unacceptable computational efficiency and accuracy on the probabilistic analysis of multi-component system with multi-failure modes, this paper proposed multi-extremum response surface method (MERSM). MERSM model was established based on quadratic polynomial function by taking extremum response surface model as the sub-model of multi-response surface method. The dynamic probabilistic analysis of an aeroengine turbine blisk with two components, and their reliability of deformation and stress failures was obtained, based on thermal-structural coupling technique, by considering the nonlinearity of material parameters and the transients of gas flow, gas temperature and rotational speed. The results show that the comprehensive reliability of structure is 0.9904 when the allowable deformations and stresses of blade and disk are 4.78×10–3 m and 1.41×109 Pa, and 1.64×10–3 m and 1.04×109 Pa, respectively. Besides, gas temperature and rotating speed severely influence the comprehensive reliability of system. Through the comparison of methods, it is shown that the MERSM holds higher computational precision and speed in the probabilistic analysis of turbine blisk, and MERSM computational precision satisfies the requirement of engineering design. The efforts of this study address the difficulties on transients and multiple models coupling for the dynamic probabilistic analysis of multi-component system with multi-failure modes.

Additional file 1: Table S1. Primers used for quantitative real-time fluorescence PCR (qRT-PCR).

Background: Recent years, PET/CT equipment has played an increasingly important role in the medical field, and its quality control and evaluation requirements have become more stringent. Correspondingly, the performance testing phantom used for PET/CT quality control needs to be upgraded and optimized to meet the requirement of equipment imaging quality testing. The commonly used NEMA IEC Body performance testing phantom has the defects that it cannot detect micro-lesion and cannot measure CT performance parameters. This article proposes a NIM PET/CT phantom capable of simultaneously testing the performance of PET and CT equipment, and evaluates its imaging quality.Methods: Compared with the NEMA IEC Body phantom, the PET performance testing module in the phantom has new balls with inner diameters of 4mm and 7mm. Combined with the CT performance testing module, it can be used for both PET and CT performance testing. The 28mm and 37mm balls are filled with pure water as a cold stove, and the remaining balls are filled with F-FDG solution as a hot stove. The activity concentration ratio of the hot ball to the background is 4:1. This study compares the imaging results of the NIM PET/CT phantom and the NEMA IEC Body phantom to verify its effectiveness; compares the imaging results of 3 different brands of PET/CT on the NIM phantom to verify that it is on different equipment The generalization ability of the system; apply PSF and TOF technology to the reconstruction algorithm and compare the improvement of the image quality; finally, the accuracy of the CT low-contrast module and the uniformity of the background are verified.Results: The imaging quality of the NIM PET/CT phantom and the NEMA IEC Body phantom is relatively consistent. The NIM phantom under different types of PET/CT scans can detect 7mm balls without affecting the imaging quality of other areas, which is better The device can detect 4mm small balls, which can clearly classify the ability of different devices to present images of small lesions; the integration of PSF technology into the reconstruction algorithm significantly improves the image resolution and hot bulb contrast, but the edges of the lesions are still blurred , TOF technology improves the detection limit of the equipment and improves the overall quality of the image. PSF&TOF technology combines the advantages of the two, significantly reducing image noise and strengthening image details, so that the image quality has been comprehensively improved; the measurement in the CT module The result is consistent with the true value, and the relative error is within ±5%. The CT value transition between the background and pure water area is smooth, and the background uniformity is good.Conclusion: NIM PET/CT Phantom and NEMA IEC Body phantom are comparability, and the former includes all the functions of the latter. In addition, the phantom can meet the testing requirement of different grades of PET/CT.

Whitefly-transmitted begomoviruses are economically important plant pathogens that cause severe problems in many crop plants, such as tomato, papaya, cotton, and tobacco. Tomato yellow leaf curl virus (TYLCV) is a typical monopartite begomovirus that has been extensively studied, but methods that can efficiently control begomoviruses are still scarce. In this study, we combined artificial microRNA (amiRNA)-mediated silencing technology and clay nanosheet-mediated delivery by spraying and developed a method for efficiently preventing TYLCV infection in tomato plants. We designed three amiRNAs that target different regions of TYLCV to silence virus-produced transcripts. Three plant expression vectors expressing pre-amiRNAs were constructed, and recombinant plasmid DNAs (pDNAs) were loaded onto nontoxic and degradable layered double hydroxide (LDH) clay nanosheets. LDH nanosheets containing multiple pDNAs were sprayed onto plant leaves. We found that the designed amiRNAs were significantly accumulated in leaves 7 days after spraying, while the pDNAs were sustainably detected for 35 days after the spray, suggesting that the LDH nanosheets released pDNAs in a sustained manner, protected pDNAs from degradation and efficiently delivered pDNAs into plant cells. Importantly, when the LDH nanosheets coated with pDNAs were sprayed onto plants infected by TYLCV, both the disease severity and TYLCV viral concentration in sprayed plants were significantly decreased during the 35 days, while the levels of H2O2 were significantly increased in those plants. Taken together, these results indicate that LDH nanosheets loaded with pDNAs expressing amiRNAs can be a sustainable and promising tool for begomovirus control.

Visceral white nodules disease (VWND) caused by Pseudomonas plecoglossicida is a common disease in cage-farmed large yellow croaker (Larimichthys crocea) in China. VWND usually occurred at water temperature of 16-19℃, resulting in high mortality in farmed large yellow croaker. Now, P. plecoglossicida as its pathogen has been considered nonpathogenic at 7-12℃. During February 2019, an infectious disease outbreak was observed in cage-farmed large yellow croaker at a water temperature of 12℃ in Ningde, China. This disease is characterized by white granulomatous lesions in internal organs of the diseased fish, which was similar with the symptoms of the VWND in large yellow croaker. Then, we isolated a bacterial strain named PQLYC4 from visceral lesions of the diseased fish. The experimental infection studies demonstrated that the strain PQLYC4 was the pathogen of the disease, which was further identified as P. plecoglossicida by the analysis of morphology, 16s rRNA gene homology and average nucleotide identity based on the whole genome sequence. Our results revealed that P. plecoglossicida strain PQLYC4 could cause the outbreak of the VWND at 12℃, a water temperature lower than that reported previously, thus providing new knowledges of prevalence and prevention of the VWND in large yellow croaker.

This study aimed to optimize the evaluation procedure of contrast to noise ratio (CNR) on low-contrast resolution (LCR) phantom images of computed tomography (CT). Axial CT images of phantom Catphan 600 which contained the low-contrast module CTP515 and the uniformity module CTP486 were acquired from five 64-slices spiral CT scanners with the same scanning parameters. Through conjoint analysis of images of CTP515 and CTP486, two steps of optimization were added to the evaluation procedure to get the optimized CNR results. Meanwhile, four experts were invited to perform the subjective evaluation of the same low-contrast images. With the method of normalization, results gained by optimized CNR and the experts' subjective evaluation were compared to investigate the consistency of the two evaluation methods. According to the comparison of the normalized values, the optimized CNR gained by the method of two-stage average could be used as basis to assist tester achieve similar result compared to that from experts' subjective evaluation.

Construct dielectric films with high energy density and efficiency are the key factor to fabricate high-performance dielectric film capacitors. In this paper, an all organic composite film was constructed based on high dielectric polymer and linear dielectric polymer. After the optimized polycondensation reaction of a linear dielectric polymer aromatic polythiourea (ArPTU), the proper molecular weight ArPTU was obtained, which was introduced into poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene) (PVDF-TrFE-CFE) terpolymer for a composite dielectrics. The results indicate that the addition of ArPTU molecules reduces the dielectric loss and improves the breakdown field strength of the PVDF-TrFE-CFE effectively. For the PVDF-TrFE-CFE/ArPTU (90/10) composite film, the maximum energy density about 22.06 J/cm3 at 407.57 MV/m was achieved, and high discharge efficiency about 72% was presented. This composite material can be casted on flexible substrate easily, and PVDF-TrFE-CFE/ArPTU organic composite films having high energy density, high breakdown field strength, low dielectric loss, and higher discharge efficiency are obtained. This is an unreported exploration about high energy density organic dielectric films based on PVDF-TrFE-CFE matrix and linear polymer dielectrics, and the findings of this research can provide a simple and scalable method for producing flexible high energy density materials for energy storage devices.

In order to more reasonable analyze the dynamic reliability of aero-engine blade with coupling failure mode. A fuzzy intelligent multiple extremum response surface method (FIMERSM) was proposed. Considering the coupling effect of temperature load and centrifugal load, the maximum stress point, the maximum strain point and the minimum life point on blade were found by deterministic analysis. Then, the density of blade, rotor speed, elastic modulus, blade-tip temperature, blade-root temperature, fatigue strength coefficient, fatigue strength exponent, fatigue ductility coefficient, fatigue ductility exponent, blade width, blade thickness, blade torsion angle, and blade height as input random variables. By using Latin hypercube sampling technique, the sample values of the input random variables were acquired and finite element basic equation was calculated for each samples which obtained the corresponding dynamic output response of their stress, strain, and low cycle fatigue life within the analysis time domain. By taking the entire maximum values of the dynamic output response in the analysis time domain as new output response, the fuzzy intelligent multiple extremum response surface function (FIMERSF) was established. Finally, the dynamic reliability of the blade structure were obtained by using the Monte Carlo method (MCM) large amount linkage sampling of the input random variables and take it into the FIMERSF to calculate the output response. The results imply that the comprehensive reliability of blade is 99.46%. Through the comparison of MCM, Multiple extremum response surface method (MERSM) and FIMERSM, the computational results show that the FIMERSM has high computational precision and computational efficiency.

Speckle is an especially relevant issue as far as self-mixing interferometry works onto diffusive targets and for large displacements sensing. This article proposed a new signal processing technique, based on three envelope extraction transition detection algorithm, to correctly extract and processes self-mixing signals corrupted by speckle. The algorithm also discriminates the direction of the target movement for different self-mixing regimes. The validity of the proposed method was demonstrated by means of simulated signals and confirmed by several experimental measurements with envelope variation of a decade in amplitude. The use of this technique effectively removes the need for optical/electro-mechanical component and strict sampling number determination.

With the vigorous development of renewable energy, large-scale wind power is connected to the power grid. Compared with conventional energy sources, wind power generation has the stochastic and intermittent characteristics, which brings great challenges to the safe and stable operation of power grids. Forecasting is essential for the rational, safe and effective use of wind power. Thus, the ability to predict wind power in a timely and accurate manner is particularly significant.The short-term prediction error of wind power is mainly caused by inherent stochastic factors and extrinsic stochastic factors. The inherent stochastic factor refers to the defect or imperfection of the prediction system itself. The external stochastic factor refers to the imperfect data input by the system or the error of the input data. Artificial neural network (ANN) algorithms are supposed to be with better performance to solve such problems. This paper reviews the development of wind power generation and the research status of wind power prediction technology. On this basis, a wind power prediction model of convolutional neural network (CNN) and genetic algorithm (GA) is constructed to predict the short-term wind power. The learning accuracy, the number of hidden nodes, and the training function are discussed. The selection of the optimal neural network and GA prediction model are presented. The simulation results show that the prediction accuracy and stability of the proposed prediction system are improved, compared with the BP neural network and CNN.

The accurate estimation of patient’s exposure to the radiofrequency (RF) electromagnetic field of magnetic resonance imaging (MRI) significantly depends on a precise individual anatomical model. In the study, we investigated the applicability of an efficient whole-body individual modelling method for the assessment of MRI RF exposure. The individual modelling method included a deformable human model and tissue simplification techniques. Besides its remarkable efficiency, this approach utilized only a low specific absorption rate (SAR) sequence or even no MRI scan to generate the whole-body individual model. Therefore, it substantially reduced the risk of RF exposure. The dosimetric difference of the individual modelling method was evaluated using the manually segmented human models. In addition, stochastic dosimetry using a surrogate model by polynomial chaos presented SAR variability due to body misalignment and tilt in the coil, which were frequently occurred in the practical scan. In conclusion, the dosimetric equivalence of the individual models was validated by both deterministic and stochastic dosimetry. The proposed individual modelling method allowed the physicians to quantify the patient-specific SAR while the statistical results enabled them to comprehensively weigh over the exposure risk and get the benefit of imaging enhancement by using the high-intensity scanners or the high-SAR sequences.

The geometrical optics approximation (GOA) method is presented to measure atmospheric visibility of rainy day. The imaginary part of refractive complex has more influences on the extinction and absorption of raindrop, but has almost no influence on the scattering of raindrop. In rainy day, when the rainfall rate increases, the visibility curves of MIE and GOA are in good agreement, but the calculation speed in GOA is faster than Mie theory on the extinction coefficient of raindrop and visibility measurement in rainy day.

Diabetes mellitus is one of major of ill health in the world. One of the popular topics in biomedical optics applications is using the near infrared spectra for non-invasive blood glucose measurement. Nonetheless, the most researches of blood glucose concentration measurement focus on the diffuse reflection either in domestic or overseas, the research of transmission is rare. In this paper, by the transmission experiment setup of non-invasive blood glucose measurement in our lab, the experiments of glucose concentration in glucose aqueous solutions based on Lambert-Beer theory are discussed. First, the optimal waveband (1310nm) is chosen for the non-invasive blood glucose concentration measurement set-up. And then, the hardware system which including laser diode, photoelectric detector and data processing module of this experiment set-up has been designed and some relevant experiments about glucose measurement are carried out. Finally, the optimal finger position of hand for human blood glucose concentration measurement is chosen. In a word, after some transmission experiments on glucose sensing??we could conclude that near infrared 1310nm light is proper for glucose concentration sensing in glucose aqueous solution, the index finger of hand is proper as the non-invasive blood glucose measurement and the transmission experiment set-up could be used for human blood glucose concentration sensing experiment later.

Considering the issue of noise reduction associated with self-mixing interference (SMI), the paper presented an empirical mode decomposition (EMD) filter algorithm for SMI laser sensor that enables more accurate reconstruction of the displacement information from an SMI signal. The performance of the algorithm is studied. It is shown that the algorithm are capable of removing white noise and high frequency noise and so on. The phase unwrapping displacement reconstructions method based on this algorithm have been experimentally validated, with laser subject to the weak and moderate feedback regime, strong feedback regime. The experimental results shown that the method could reduce reconstruction error in simulations and experiments.

Non-contact measurement has the characteristics of high speed and high efficiency, which fit the requirements of the measurement of engine blade. According to high-speed and efficient measurement in the condition of high precision, we design a point laser beam direction calibration method based on a standard ball by analysing the mathematical model. By experiment, it proves that the stability and accuracy can meet the requirements of blade measurement.

The different positions and angles of the optical sensor are calibrated before using the optical coordinate measuring system. In this paper, we analyze and optimize the common calibration process, reduce the unnecessary links, shorten the calibration time, and improve the efficiency of the optical coordinate measuring system by 50 percent.

Eye movements were recorded using infrared oculography in 17 patients with motor neurone disease (MND) and in 17 age-matched controls. Major findings were a marked reduction in pursuit gain for the severely affected patient group as target speed increased from 10 deg/sec to 20 deg/sec and asymmetric pursuit (leftward gain lower than rightward) in these patients. The authors’ study illustrates the effect of MND on the central pathways of the nervous system which control eye movements and shows that an association may exist between specific ocular motor defects and severity.

In traditional acupuncture, reinforcement and reduction are conducted to stimulate the channel Qi by puncturing or heating the points with specific manners so as to regulate the functional activities of the internal organs. Reinforcement and reduction manners played an important role in clinical practice of traditional Chinese medicine, especially in disease curing. And the non-invasive nature of laser acupuncture has made lasers an attractive alternative in Medical Acupuncture at the last 25 years. The objective of this paper was to introduce the methods to implement reinforcement and reduction in laser acupuncture. According to reinforcement and reduction of traditional acupuncture and the theory of laser optics, lifting and thrusting of acupuncture, twisting and twirling of acupuncture and sparrow-pecking moxibustion are implemented.

The non-invasive nature of laser biostimulation has made lasers an attractive alternative in medical acupuncture at the last 25 years. To get much better effect of laser acupuncture, the objective of this work was to design and build a low cost portable laser acupuncture instrument which can implement reinforcement and reduction of traditional acupuncture. According to reinforcement and reduction of traditional acupuncture and the theory of laser optics, lifting and thrusting of acupuncture, and twisting and twirling of acupuncture are implemented. The laser source is 30 mW AlGalnP laser diode with an emission wavelength of 650 nm. The MSP430 microcontroller system is used as the control center of the device.

Cardiac Diseases are very harmful to the human health. The application of electrocardiogram (ECG) is essential for the clinical diagnosis of cardiac diseases. The use of computers for accurately and quickly cardiac disease diagnosis has been a subject fervently pursued by both internal and external researchers. Therefore, it is great significant to explore even more accurate and higher-speed automatic ECG analysis method. Support Vector Machine (SVM) is a novel powerful machine learning method based on statistical learning theory, which is powerful for the characterization of small sample (nonlinearity, high dimension and local minima). In this paper, Clinical diagnosis of cardiac disease based on SVM is proposed. There are two input patterns of samples: 8-lead ECG in series and in parallel. All experiments are implemented on Pentium 350 MHz with 512 MB RAM. Matlab 6.5 is employ to solve the quadratic programming. Comparison in two input patterns based on SVM, the result shows that SVM method in parallel is highly reliable and accurate. It will have great potential application in clinical diagnosis.

With the increasing performance of computer, the virtual instrument technology has greatly advanced over the years, and then virtual medical instrument technology becomes available. This paper presents the virtual medical instrument, and then as an example, an application of a signal acquisition, processing and analysis system using LabVIEW is also given.

Laser acupuncture is defined as the stimulation of traditional acupuncture points with low-intensity, non-thermal laser irradiation. It has been well applied in clinic since the 1970s; however, some traditional acupuncture manipulating methods still cannot be implemented in the design of this kind of instruments, such as lifting and thrusting manipulating method, and twisting and twirling manipulating method, which are the essential acupuncture method in traditional acupuncture. The objective of this work was to design and build a low cost portable laser acupuncture therapeutic instrument, which can implement the two essential acupuncture manipulating methods. Digital PID control theory is used to control the power of laser diode (LD), and to implement the lifting and thrusting manipulating method. Special optical system is designed to implement twisting and twirling manipulating method. M5P430 microcontroller system is used as the control centre of the instrument. The realization of lifting and thrusting manipulating method and twisting and twirling manipulating method are technological innovations in traditional acupuncture coming true in engineering.

To cure brain paralysis this paper has briefly summarized the rudimentary knowledge of the ultrasonic therapy, and briefly introduced the methods of dolphin ultrasonic therapy, through the research of the dolphin ultrasonic therapy, the ultrasonic frequency chart wave band which is more efficient to the therapy of brain paralysis is measured, and one method of simulated dolphin therapy mechanism is found. Finally, one of the ultrasonic therapy instruments against brain paralysis is developed.