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Autophagy is an evolutionarily conserved degradation pathway of lysosomes (in mammals) and vacuoles (in yeasts and plants) from lower yeasts to higher mammals. It wraps unwanted organelles and damaged proteins in a double-membrane structure to transport them to vacuoles for degradation and recycling. In plants, autophagy functions in adaptation to the environment and maintenance of growth and development. This review systematically describes the autophagy process, biological functions, and regulatory mechanisms occurring during plant growth and development and in response to abiotic stresses. It provides a basis for further theoretical research and guidance of agricultural production. [ABSTRACT FROM AUTHOR]

This paper proposes a new rolling bearing fault diagnosis method based on adaptive multiscale fuzzy entropy (AMFE) and support vector machine (SVM). Unlike existing multiscale Fuzzy entropy (MFE) algorithms, the scales of AMFE method are adaptively determined by using the robust Hermite-local mean decomposition (HLMD) method. AMFE method can be achieved by calculating the Fuzzy Entropy (FuzzyEn) of residual sums of the product functions (PFs) through consecutive removal of high-frequency components. Subsequently, the obtained fault features are fed into the multi-fault classifier SVM to automatically fulfill the fault patterns recognition. The experimental results show that the proposed method outperforms the traditional MFE method for the nonlinear and non-stationary signal analysis, which can be applied to recognize the different categories of rolling bearings. [ABSTRACT FROM AUTHOR]

Local mean decomposition (LMD) is a novel adaptive time-frequency analysis method, which is widely used in reciprocating compressor fault diagnosis. However, LMD decomposition results method is sensitive to noise. In order to eliminate influence of noise, cascaded bistable stochastic resonance (CBSR) is introduced and a new fault diagnosis method based on CBSR denoising and LMD is proposed in this paper. Firstly, CBSR is employed as the pretreatment to remove noise in vibration signals, and then the denoised signal is decomposed by LMD method. Finally, the fault frequency of reciprocating compressor is found through the envelope spectrum analysis of the first PF component. The effectiveness of the proposed method is verified by the simulation data and the practical reciprocating compressor fault diagnosis. [ABSTRACT FROM AUTHOR]

Empirical mode decomposition (EMD), a self-adaptive time-frequency analysis methodology, is particularly suitable for processing the nonlinear and non-stationary time series, which can decompose a complicated signal into a series of intrinsic mode functions. Although it has the attractive features, the approach to construct the envelop-line in EMD has obvious shortcomings. A suggested improvement to EMD by adopting the optimized rational Hermite interpolation is proposed in this paper. In the proposed method, it adopts rational Hermite interpolation to compute the envelope-line, which has a shape controlling parameter compared with the cubic Hermite interpolation. In the meantime, one parameter determining criterion is introduced to guarantee the shape controlling parameter selection performs optimally. Besides the empirical envelope demodulation (EED) is introduced and utilized to analyze the IMFs derived from the improved EMD method. Hence, a new time-frequency method based on the optimized rational Hermite-based EMD combined with EED is proposed and the effectiveness was validated by the numerical simulations and an application to the reciprocating compressor fault diagnosis. The contributions of this paper are three aspects: Firstly, the definition of the best envelope is non-existent, some light is given about which envelope maybe better in this paper. Secondly, the optimal shape controlling parameter selection combined with rational Hermite interpolation is developed, leading to the significant performance enhancement. Thirdly, little research has been carried out on the fault diagnosis of the reciprocating compressor using EMD, the proposed method is a good start. [ABSTRACT FROM AUTHOR]

Since the vibration signals of gearbox are non-linear and non-stationary, it is difficult to accurately evaluate the working conditions. Therefore, a fault feature extraction technique based on intrinsic characteristic-scale decomposition (ICD) and multi-scale entropy (MSE) is presented in this paper. The measured signals are firstly decomposed into a series of product components (PCs) by ICD. Secondly, the main product component is selected, and then MSE is used to extract the feature vectors from the selected PCs. Finally, the obtained feature vectors of gearbox with different scale factors are adopted as inputs of support vector machine (SVM) to fulfill the fault patterns identification. The superiority of the proposed technique is verified through comparing with three other methods. [ABSTRACT FROM AUTHOR]

This paper presents a fault diagnosis method for gearbox based on local mean decomposition (LMD), permutation entropy (PE) and extreme learning machine (ELM). LMD, a new self-adaptive time-frequency analysis method, is applied to decompose the vibration signal into a set of product functions (PFs). Then, PE values of the first five PFs (PF-PE) are calculated to characterize the complexity of the vibration signal. Finally, for the purpose of less time-consuming and higher accuracy, ELM is used to identify and classify of gearbox in different fault types. The experimental results demonstrate that the proposed method is effective in diagnosing and classifying different states of gearbox in short time. [ABSTRACT FROM AUTHOR]

The factors inducing normally innervated Schwann cells in peripheral nerve to divide are poorly understood. Transection of the fourth and fifth lumbar ventral roots (L4/5 ventral rhizotomy) of the rat is highly selective, sparing unmyelinated axons and myelinated sensory axons; Wallerian degeneration is restricted to myelinated efferent fibers. We found that L4/5 ventral rhizotomy prompted many normally innervated nonmyelinating (Remak) Schwann cells to enter cell cycle; myelinating Schwann cells of intact (sensory) axons did not. Three days after L4/5 ventral rhizotomy, [3H]thymidine incorporation into Remak Schwann cells increased 30-fold. Schwann cells of degenerating efferents and endoneurial cells also incorporated label. Increased [3H]thymidine incorporation persisted at least 10 d after ventral rhizotomy. Despite Remak Schwann cell proliferation, the morphology of unmyelinated nerve (Remak) bundles was static. Seven days after L5 ventral rhizotomy, Remak Schwann cells in the L5-predominant lateral plantar nerve increased slightly; endoneurial cells doubled. Terminal deoxynucleotidyl transferase-mediated biotinylated UTP nick end labeling-positive nuclei increased dramatically in peripheral nerve after L5 ventral rhizotomy; many of these were macrophage nuclei. In summary, we find that the degeneration of myelinated motor axons produced signals that were mitogenic for nonmyelinating Schwann cells with intact axons but not for myelinating Schwann cells with intact axons. [ABSTRACT FROM AUTHOR]

Tomato yellow leaf curl virus (TYLCV) responsible for tomato yellow leaf curl disease (TYLCD) causes a substantial decrease in tomato (Solanum lycopersicum L.) yield worldwide. The use of resistant variety as a sustainable management strategy has been advocated. Tremendous progress has been made in genetically characterizing the resistance genes (R gene) in tomato. Breeding tomato for TYLCV resistance has been based mostly on Ty-3 as a race-specific resistance gene by introgression originating from wild tomato species relatives. Improvement or development of a cultivar is achievable through the use of marker-assisted selection (MAS). Therefore, precise and easy use of gene-targeted markers would be of significant importance for selection in breeding programs. The present study was undertaken to develop a new marker based on Ty-3 gene sequence that can be used for MAS in TYLCV resistant tomato breeding program. The new developed marker was named ACY. The reliability and accuracy of ACY were evaluated against those of Ty-3 linked marker P6-25 through screening of commercial resistant and susceptible tomato hybrids, and genetic segregation using F2 population derived from a commercial resistant hybrid AG208. With the use of bioinformatics and DNA sequencing analysis tools, deletion of 10 nucleotides was observed in Ty-3 gene sequence for susceptible tomato variety. ACY is a co-dominant indel-based marker that produced clear and strong polymorphic band patterns for resistant plant distinguishing it from its susceptible counterpart. The obtained result correlates with 3:1 segregation ratio of single resistant dominant gene inheritance, which depicted ACY as gene-tag functional marker. This marker is currently in use for screening 968 hybrids varieties and one thousand breeding lines of tomato varieties stocked in Jiangsu Green Port Modern Agriculture Development Company (Green Port). So far, ACY has been used to identify 56 hybrids and 51 breeding lines. These newly detected breeding lines were regarded as potential source of resistance for tomato breeding. This work exploited the sequence of Ty-3 and subsequently contributed to the development of molecular marker ACY to aid phenotypic selection. We thus recommend this marker to breeders, which is suitable for marker-assisted selection in tomato. [ABSTRACT FROM AUTHOR]

Percussive-rotary drilling is an effective method for the hard rock drilling. As hydraulic and pneumatic hammers have many problems especially in the deep core drilling, a new electromagnetic hammer driven by a tube linear motor is introduced in this study. The study mainly covers the mechanical structure and electromagnetic design of the hammer, respectively. Due to the direct use of electric power, the electromagnetic hammer has the advantage of high efficiency while it must meet the minimal percussive energy requirement under the limitation of drill pipe diameter. In this study, the validity of electromagnetic design is verified through the finite-element analysis software Ansoft/Maxwell 2D and numerical calculation of electromagnetic force. The working temperature in deep down-hole is relatively high, the influence of high temperature in deep hole on the electromagnetic thrust of the linear motor is then analysed. A motion model of linear motor hammer is established to calculate and analyse the impact power and frequency under different conditions. The results show that the performance of linear motor hammer can reach or even exceed the one of same diameter hydraulic hammer, especially in the low-frequency range. The prototype test also confirms the validity of the design. [ABSTRACT FROM AUTHOR]

Abstract: Photocatalytic oxidation of dibenzothiophene (DBT) with hydrogen peroxide using TS-1 as photocatalyst at ultraviolet lamp irradiation has been studied. The result showed DBT was photooxidized successfully, regardless of steric limitations. Optimal reaction conditions were investigated in detail. Photooxidized products of DBT are DBT 5-oxide, DBT 5,5-dioxide and SO4 2− by mass spectrum. Kinetics parameters of the photocatalytic oxidation of DBT were measured and calculated. The kinetics of photocatalytic oxidation of DBT is fist-order. Mechanism of photocatalytic oxidation of DBT by TS-1 was analyzed. [Copyright &y& Elsevier]