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Based on the idea of nodal cavity method, the simulation platform of constant deceleration braking system is built in Simulink. According to JKMD 4.5 × 4 mine hoist and its matching E141A constant ...

With the continuous progress of modern industry, rotating machinery is gradually developing toward complexity and intelligence. The fault diagnosis technology of rotating machinery is one of the key means to ensure the normal operation of equipment and safe production, which has very important significance. Deep learning is a useful tool for analyzing and processing big data, which has been widely used in various fields. After a brief review of early fault diagnosis methods, this paper focuses on the method models that are widely used in deep learning: deep belief networks (DBN), autoencoders (AE), convolutional neural networks (CNN), recurrent neural networks (RNN), generative adversarial networks (GAN), and transfer learning methods are summarized from the two aspects of principle and application in the field of fault diagnosis of rotating machinery. Then, the commonly used evaluation indicators used to evaluate the performance of rotating machinery fault diagnosis methods are summarized. Finally, according to the current research status in the field of rotating machinery fault diagnosis, the current problems and possible future development and research trends are discussed.

The past few decades have seen major discoveries in the field of molecular plant-microbe interactions. As the result of technological and intellectual advances, we are now able to answer questions at a level of mechanistic detail that we could not have imagined possible 20 years ago. The MPMI Editorial Board felt it was time to take stock and reassess. What big questions remain unanswered? We knew that to identify the fundamental, overarching questions that drive our research, we needed to do this as a community. To reach a diverse audience of people with different backgrounds and perspectives, working in different areas of plant-microbe interactions, we queried the more than 1,400 participants at the 2019 International Congress on Molecular Plant-Microbe Interactions meeting in Glasgow. This group effort resulted in a list of ten, broad-reaching, fundamental questions that influence and inform our research. Here, we introduce these Top 10 unanswered questions, giving context and a brief description of the issues. Each of these questions will be the subject of a detailed review in the coming months. We hope that this process of reflecting on what is known and unknown and identifying the themes that underlie our research will provide a framework to use going forward, giving newcomers a sense of the mystery of the big questions and inspiring new avenues and novel insights.

[EN] Bromoviridae is a family of plant viruses with tri-segmented, positive-sense, single-stranded RNA genomes of about 8 kb in total. Genomic RNAs are packaged in separate virions that may also contain subgenomic, defective or satellite RNAs. Virions are variable in morphology (spherical or bacilliform) and are transmitted between hosts mechanically, in/on the pollen and non-persistently by insect vectors. Members of the family are responsible for major disease epidemics in fruit, vegetable and fodder crops such as tomato, cucurbits, bananas, fruit trees and alfalfa. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Bromoviridae, which is available at www.ictv.global/report/bromoviridae., Production of this summary, the online chapter and associated resources was funded by a grant from the Wellcome Trust (WT108418AIA). Members of the ICTV (10th) Report Consortium are Elliot J. Lefkowitz, Andrew J. Davison, Stuart G. Siddell, Peter Simmonds, Sead Sabanadzovic, Donald B. Smith, Richard J. Orton and F. Murilo Zerbini.

In this study, we demonstrate a novel pro-viral role for the Nicotiana benthamiana ARGONAUTE 1 (AGO1) in potyvirus infection. AGO1 strongly enhanced potato virus A (PVA) particle production and benefited the infection when supplied in excess. We subsequently identified the potyviral silencing suppressor, helper-component protease (HCPro), as the recruiter of host AGO1. After the identification of a conserved AGO1-binding GW/WG motif in potyviral HCPros, we used site-directed mutagenesis to introduce a tryptophan-to-alanine change into the HCPro (HCProAG) of PVA (PVAAG) and turnip mosaic virus (TuMVAG). AGO1 co-localization and co-immunoprecipitation with PVA HCPro was significantly reduced by the mutation suggesting the interaction was compromised. Although the mutation did not interfere with HCPro’s complementation or silencing suppression capacity, it nevertheless impaired virus particle accumulation and the systemic spread of both PVA and TuMV. Furthermore, we found that the HCPro-AGO1 interaction was important for AGO1’s association with the PVA coat protein. The coat protein was also more stable in wild type PVA infection than in PVAAG infection. Based on these findings we suggest that potyviral HCPro recruits host AGO1 through its WG motif and engages AGO1 in the production of stable virus particles, which are required for an efficient systemic infection., Author summary In the course of an infection viral proteins come regularly into contact with host factors. Knowledge of these virus-host interactions in plants is essential for understanding the progress of infections and for addressing challenges in the production of healthy plants, which is important for global food security. In this study we report that the potyviral Helper component proteinase (HCPro) recruits host ARGONAUTE1 protein and engages it in pro-viral functions. We found that the interaction of potato virus A HCPro with ARGONAUTE1 benefited the infection by promoting the stability and accumulation of virus particles. When HCPro was engineered to disrupt the interaction, we detected very few virus particles and observed that the mutated virus did not spread efficiently. Thus, we propose that the interaction between HCPro and ARGONAUTE1 has biological relevance as it is important for formation of stable particles and achieving optimal systemic infection.

The endoplasmic reticulum (ER) endomembrane is a central site for protein synthesis. Perturbation of ER homeostasis can result in an accumulation of unfolded proteins within the ER lumen, causing ER stress and the unfolded protein response (UPR). In humans, ER stress and UPR are closely associated with a vast number of diseases, including viral diseases. In plants, two arms that govern the UPR signaling network have been described: one that contains two ER membrane–associated transcription factors (bZIP17 and bZIP28) and the other that encompasses a dual protein kinase (RNA-splicing factor IRE1) and its target RNA (bZIP60). Although early studies mainly focus on the essential roles of the UPR in abiotic stresses, the significance of UPR in plant diseases caused by virus infections has recently drawn much attention. This chapter summarizes the latest scenario of ER stress and UPR in virus-infected plant cells, highlights the emerging roles of the IRE1 pathway in virus infections, and outlines exciting future directions to spark more research interest in the UPR field in plants.

Plants have evolved sophisticated surveillance and defense mechanisms against constant attacks by different types of microbial pathogens including viruses. Nucleotide-based RNA silencing and receptor-based innate immunity constitute the primary plant defense to viral infection. To establish their infections, plant viruses have also evolved virulence strategies to suppress host defenses. This ever-lasting co-evolutionary arms race between the plant hosts and viruses has shaped today's multifaceted defense and counter-defense layout. A better understanding of this process will certainly assist in the development of new plant varieties with enhanced durable resistance and novel approaches to control viral pathogens for sustainable agriculture. In this addendum, we briefly review the current knowledge of the plant immune response to viral infection and discuss defense and counter-defense strategies.

Plant viral infection results in a multi-billion dollar economic loss worldwide each year. The use of genetic resistance is the most effective and sustainable approach to the control of plant viral diseases. However, owing to the lack of natural resistance genes, a single devastating viral pathogen often becomes a significant limiting factor in crop production. All plant viruses have a small viral genome that encodes a limited number of viral proteins. They must depend on host gene products (host factors) to complete their life cycle. Mutation, silencing or down-regulation of host factor gene(s) may lead to recessively inherited resistance to viruses. This is a major driving force for the molecular identification and functional characterization of host factors essential in virus infections. Potyviruses represent over 30% of all known plant viruses and constitute the largest plant virus group. Many agriculturally important viruses are potyviruses. In the last decade, several potyviral host factor genes including the well-known eIF4E or eIF(iso)4E gene have been molecularly identified. In this review, I will summarize research progress in molecular understanding of potyviral infection processes, and discuss manipulation of the identified host factors against potyviruses.

Cultured free round pearls are produced by implanting a spherical nucleus with a small piece of nacre-secreting mantle graft from a donor oyster into the gonad of a recipient oyster (host). To examine the possible contribution of host and donor oysters to the colouration of the harvested pearls, the CSE-1 Imaging and Color-Measuring System were used to quantitatively measure the L*a*b* values of donor and host shells and the produced pearls in Pinctada martensii. Results showed that the colour of pearls had significant positive correlation (r = 0.1–0.22, P = 0.00) with that of donors, but had no correlation with that of host oysters, thus convincingly confirmed the contribution of nacre colour of donor to the realization of pearl quality of colour. To further clarify the relationship between the donor and the pearl colour, the donors from pearls of good and poor colour quality were further compared and the results demonstrated the significant difference in L* values (P

Metformin is an effective insulin sensitizer treating type 2 diabetes mellitus. However, the functional consequences of metformin administration throughout pregnancy on gestational diabetes mellitus (GDM) with polycystic ovary syndrome (PCOS) have not been assessed. We therefore performed a meta-analysis and system review to determine the effect of metformin on GDM in PCOS. A meta-analysis was performed on the published studies before December, 2013. Meta-analysis examined whether metformin could reduce GDM occurrence in PCOS with a fixed effect model. The odds ratio (OR) with 95% confidence interval (95% CI) was calculated to estimate the strength of association. A total of 13 studies including 5 RCTs and 8 non-RCTs were enrolled. Ultimately, effectiveness analysis demonstrated that, in total, there was no significant availability of metformin on GDM in PCOS in contrast to placebo (OR = 1.07, 95% CI 0.60–1.92) in RCTs and significant availability of metformin on GDM (OR = 0.19, 95% CI 0.13–0.27) was indicated in non-RCTs. In summary, according to the results of our meta-analysis, strictly, metformin did not significantly effect on GDM with PCOS, though more multicenters RCTs still need to be investigated.

The use of genetic resistance is considered to be the most effective and sustainable approach to the control of plant pathogens. Although most of the known natural resistance genes are monogenic dominant R genes that are predominant against fungi and bacteria, more and more recessive resistance genes against viruses have been cloned in the last decade. Interestingly, of the 14 natural recessive resistance genes against plant viruses that have been cloned from diverse plant species thus far, 12 encode the eukaryotic translation initiation factor 4E (eIF4E) or its isoform eIF(iso)4E. This review is intended to summarize the current state of knowledge about eIF4E and the possible mechanisms underlying its essential role in virus infection, and to discuss recent progress and the potential of eIF4E as a target gene in the development of genetic resistance to viruses for crop improvement.

The end of fully mechanized caving face is keystone and difficulty on protecting and managing the top. The effect on supporting the end of work face is very importment to mechanical and electrical machine, and very importment to workers' safety. The text analyze the problem of supporting the end at present, and Aiming at these problem, reach and manufact the fully mechanized caving face supporting system, then introducing the system's whole structure and control mode and key components particularly.

The viral genome-linked protein, VPg, of potyviruses is a multifunctional protein involved in viral genome translation and replication. Previous studies have shown that both eukaryotic translation initiation factor 4E (eIF4E) and eIF4G or their respective isoforms from the eIF4F complex, which modulates the initiation of protein translation, selectively interact with VPg and are required for potyvirus infection. Here, we report the identification of two DEAD-box RNA helicase-like proteins, PpDDXL and AtRH8 from peach (Prunus persica) and Arabidopsis (Arabidopsis thaliana), respectively, both interacting with VPg. We show that AtRH8 is dispensable for plant growth and development but necessary for potyvirus infection. In potyvirus-infected Nicotiana benthamiana leaf tissues, AtRH8 colocalizes with the chloroplast-bound virus accumulation vesicles, suggesting a possible role of AtRH8 in viral genome translation and replication. Deletion analyses of AtRH8 have identified the VPg-binding region. Comparison of this region and the corresponding region of PpDDXL suggests that they are highly conserved and share the same secondary structure. Moreover, overexpression of the VPg-binding region from either AtRH8 or PpDDXL suppresses potyvirus accumulation in infected N. benthamiana leaf tissues. Taken together, these data demonstrate that AtRH8, interacting with VPg, is a host factor required for the potyvirus infection process and that both AtRH8 and PpDDXL may be manipulated for the development of genetic resistance against potyvirus infections.

Tomato ringspot nepovirus (TomRSV) encapsidates a bipartite, messenger sense RNA genome. RNA-1 is likely to encode all the viral proteins required for RNA replication. The expression and processing strategies of the RNA-1-encoded polyprotein (PI) were studied. It was found that PI is intramolecularly proteolytically processed by a virus-encoded protease at five cleavage sites to release six end products, i.e. XI, X2, NTB, VPg, Pro and Pol. All PI cleavage sites were identified. The genomic organization of TomRSV RNA-1 is distinct from that of the closely related comoviruses and of other nepoviruses. In TomRSV, two mature proteins (XI and X2) are released from the region upstream of NTB whereas only one mature protein is released from the corresponding region in all other characterized nepo- and comoviruses. Viral RNA replication is thought to be carried out by a replication complex which is secured on cellular membranes by a virus-encoded protein. To test if the NTB-VPg protein which contains a predicted trans-membrane domain is the anchor protein, association of this protein with microsomal membranes was studied in vitro. It was found that the NTB-VPg protein is an integral membrane protein and that the predicted transmembrane domain at the C-terminus of NTB is required for the membrane-association. The association of the NTB-VPg protein with microsomal membranes results in the generation of glycosylated and signal peptidase-processed proteins. The importance of these modifications for viral RNA replication needs to be elucidated. The molecular variability of the RNA-1-encoded replication-related viral proteins including VPg, Pro and Pol, and of the RNA-2-encoded coat protein among five TomRSV isolates was studied. It was found that the nucleotide sequences and the deduced amino acid sequences of RNA-1 were more conserved than those of RNA-2. Amino acid substitutions were not found in all conserved motifs identified previously in the protease and polymerase domains. Furthermore, the VPg amino acid sequence was identical in all isolates studied despite some variations at the nucleotide sequence level. The above results are discussed in light of the possible strategies for processing of the PI polyprotein and for the formation of the replication complex on cellular membranes.

Transient expression via agroinfiltration and/or viral vectors has quickly emerged as the preferred expression system for plant-made recombinant proteins. Transient expression can serve as a valuable research tool for finding optimal expression parameters before tedious and time-consuming production of stable transgenic plants or it can be scaled up to commercial production scale with vacuum infiltration. This technology is poised to compete with conventional production systems, large-scale production facilities are currently available and others are in the process of development. This chapter will introduce background and rationale in development of transient expression systems in plants and summarize the latest developments and examples in this area.