Effects of the Slot Harmonics on the Stator Current in an Induction Motor with Bearing Fault

Bearing faults are the most frequent faults of induction motors. The current spectrum analysis is an easy and popular method for the monitoring and detection of bearing faults. After a presentation of the existing fault models, this paper illustrates an analytical approach to evaluate the effects of the slot harmonics on the stator current in an induction motor with bearing fault. Simple and clear theoretical analysis results in some new current characteristic frequencies. Experimental tests with artificial bearing outer raceway fault are carried out by measuring stator current signals. The experimental results by spectral analysis of the stator current agree well with the theoretical inference

Optimal Sprinkler Application Rate of Water–Fertilizer Integration Machines Based on Radial Basis Function Neural Network

The application rate for sprinkler irrigation of water–fertilizer integration machines is an important technical parameter for efficient operation. If the value is too large, the equipment will produce runoff; if it is too small, the equipment will run too long and waste energy. Therefore, it is necessary to provide a feasible scientific and theoretical basis for developing a reasonable application rate. In this study, a mathematical model of soil infiltration for sprinkler irrigation with water and fertilizer integration machines was developed. Soil water accumulation time for different soil’s initial water content, bulk density, sprinkler application rate and soil texture were derived by the finite element method, and these data were used as a training database for the neural network. To make the neural network convenient for predicting the optimal application rate of sprinkler irrigation (the maximum application rate of sprinkler irrigation without runoff) in practice, the time of waterlogging, was multiplied by the optimal application rate of sprinkler irrigation to obtain the total irrigation volume. The optimal application rate of the sprinkler irrigation prediction model of radial basis function (RBF) neural network was constructed with total irrigation water, soil bulk density, initial water content and soil texture as inputs and compared with BP neural network and generalized regression neural network. The highest prediction accuracy of RBF neural network was obtained, and its average relative error was 0.11. To verify the accuracy of the RBF neural network application rate of sprinkler irrigation prediction model in real life, a sprinkler experiment was conducted in the laboratory of Guangzhou University, and the collected soil and lawn of Guangzhou University were used to simulate the actual environment. The results showed that the relative error between the RBF neural network prediction results and the actual values was generally around 10%, while for a total irrigation volume of 58 mm, the optimal application rate of sprinkler irrigation calculated with the model was 42 (mm/h), which can save 70% of irrigation time compared to the case of using the stable infiltration rate of soil as the application rate of sprinkler irrigation without water and fertilizer. Water and fertilizer losses were not observed. This indicates that the model proposed in this study is of practical value in determining the optimum application rate of sprinkler irrigation for water–fertilizer integration machines

Imaging and pathological characteristics, treatment, and prognosis of pulmonary sequestration—A retrospective study of 13 cases

Abstract Objective This study aimed to summarize and analyze the characteristics of pulmonary sequestration to improve our understanding of this disease. Methods Between January 2019 and April 2023, the clinical data of 13 patients with pulmonary sequestration underwent surgical treatment at the First Affiliated Hospital of Gannan Medical University. Results The male‐to‐female ratio was 4:9, the age was 0.5 to 60 years, and the average age was 38 ± 19 years. There were 10 and 3 cases of intralobar and extralobar pulmonary sequestration, respectively. Chest enhanced computed tomography (CT) and three‐dimensional vascular reconstruction showed that the abnormal blood vessels were derived from the descending thoracic aorta in nine cases and from other blood vessels in four cases. Three patients underwent thoracoscopic lobectomy, two underwent thoracoscopic segmentectomy, and eight underwent thoracoscopic wedge resection. All the patients successfully completed the surgery and were discharged postoperatively. Conclusions Some patients with pulmonary sequestration exhibit no obvious symptoms. Patients with clinical symptoms are easily confused for pneumonia, bronchial cysts, lung abscesses, and lung tumors; therefore, patients with pulmonary sequestration are prone to missed diagnosis and misdiagnosis. Currently, enhanced chest CT combined with three‐dimensional vascular reconstruction can accurately show the course, branches, and relationship with the mass of the feeding artery. Routine pathological examination is helpful to further clarify the diagnosis of pulmonary sequestration. Minimally invasive thoracoscopic surgery is the preferred treatment for patients with pulmonary sequestration. Surgical resection is safe and feasible, and satisfactory results are typically obtained

Identification and Characterization of miR164-NAC Regulatory Modules in Banana

【Objective】This study aims to understand the roles of MIR164, NAC gene families and miR164-NAC regulatory modules in banana ripening and response to low temperature stress, so as to provide a theoretical basis for banana variety improvement and molecular breeding.【Method】'Brazil banana' was used as test material. Through high-throughput sequencing and bioinformatics analysis using miRBase, NCBI database and Clustal, TBtools, MCScanX and iTOL softwares, miR164 and NAC family members in banana were characterized, including their chromosomal location, structure, physical/ chemical properties, phylogenetic relationships, etc. Multiple miR164-NAC regulatory modules in bananas were identified through degradome sequencing and experimental validation combining transcriptome data. Next, the expression patterns of miR164-NAC regulatory modules during ripening and under cold stress were analyzed by small RNA northern blot and qRT-PCR.【Result】A total of six miR164 family members were identified in banana, of which four were located within the coding genes and two in the intergenic region. Phylogenetic analysis showed that several banana MIR164 precursors with high abundance were clustered together with papaya, suggesting that the origin of banana MIR164 gene family was closer to dicotyledonous plants. The banana genome encodes a total of 222 NAC members, unevenly distributed across all 11 chromosomes. A total of 134 homologous gene pairs were identified in these banana NACs, including 4 tandem repeats and 130 segment-replicating repeats, indicating that the main driving force of banana NAC genes evolution came from segmentreplicating events. Comparative phylogenetic analysis of all NAC proteins in banana, Arabidopsis thaliana and Oryza sativa divided this family into 23 subgroups, and transcriptome data revealed extensive redundancy and expression specificity of banana NAC genes. Physicochemical analysis showed that almost all banana NAC proteins were hydrophilic, and less than 15% were stable proteins. The miR164-NAC176/165 regulatory module in banana was verified, and the accumulation of miR164 in banana was induced by ethylene and gradually increased with fruit ripening, while the expression of MaNAC176/165 negatively regulated by miR164 in this module was gradually decreased during fruit ripening. Under the cold stress, miR164 was also obviously induced, resulting in the downregulation of its targets MaNAC176 and MaNAC165.【Conclusion】This study suggested that MaNAC176 and MaNAC165 may be transcriptional repressors of banana fruit ripening, while miR164 promotes ripening by negatively regulating MANAC176/165. This module may also be a key regulatory pathway of banana chilling injury. This study identified key miR164-NAC candidate modules in banana fruit ripening and cold stress response, which laid a foundation for subsequent gene cloning and functional analysis

microRNA regulation of fruit development, quality formation and stress response

Fruits, as the reproductive organs of many higher plants, are an integral part of a balanced diet, providing rich nutrients and bioactive substances for our health. Over the years, the research on fruit development, quality formation and stress response has deepened, which sheds light on the regulatory mechanism and application of fruit quality improvement. Among the many regulatory factors, microRNAs (miRNAs) are a class of short non-coding RNAs, ranging from 20 to 24-nt, which post-transcriptionally regulate target gene expression. miRNAs and their functions have been extensively examined in plants especially in model species, and they play critical roles in the regulation of diverse biological processes in response to endogenous developmental signals and external environmental cues, respectively. In fruit crops, the function of miRNAs and their regulation have also been under intensive study. In particular, the novel roles of miRNAs that have not been revealed in the model annual species have been unraveling, which reflect the genetic, physiological, and developmental complexity of gene regulation in fruit crops. Here we review the current research progress achieved, specifically in fruit crops, with a focus on the function of miRNAs in the control of fruit development and quality as well as response to various stresses. The future prospects of miRNAs for quality-targeted fruit breeding are also discussed

A novel method to design Nb(W)–Ti–Co(Fe) alloy membrane with high hydrogen permeability and strong resistance to hydrogen embrittlement

A hydrogen permeable Nb43W5Ti27Co20Fe5 alloy membrane was designed and its microstructure and hydrogen transportation performances were systematically studied. W mainly dissolves into primary body-centered cubic (bcc)-(Nb) phases, while Fe is captured in eutectic structures. Substituting Nb with W leads to a substantial reduction in hydrogen solubility and substituting Co with Fe negligibly affects hydrogen solubility. The W and Fe substitutions contribute to an enhanced intrinsic hydrogen diffusion coefficient D∗. The designed Nb43W5Ti27Co20Fe5 alloy membrane exhibits lower hydrogen solubility and higher hydrogen permeability at temperatures below 623 K than that of the original Nb48Ti27Co25 alloy membrane. No hydrogen-induced failures were found for the designed Nb43W5Ti27Co20Fe5 alloy membrane during cooling to room temperature and under long-term hydrogen permeation at 673 K for 72 h, whereas the original alloy membrane failed at 444 K during cooling to room temperature and after 19 h during hydrogen permeation at 673 K. The designed Nb43W5Ti27Co20Fe5 alloy membrane exhibits high hydrogen permeability and strong resistance to hydrogen embrittlement

Quantitative and correlation analysis of the DNA methylation and expression of DAPK in breast cancer

Background Death-associated protein kinase 1 (DAPK) is an important tumor suppressor kinase involved in the regulation of multiple cellular activities such as apoptosis and autophagy. DNA methylation of DAPK gene was found in various types of cancers and often correlated with the clinicopathological characteristics. However, the mRNA and protein expression of DAPK in the same sample was rarely measured. Thus, it was unclear if the correlation between DAPK gene methylation and clinicopathological parameters was due to the loss of DAPK expression. Methods In this study, the DNA methylation rate, mRNA and protein expression of DAPK was quantitatively detected in 15 pairs of breast cancer patient samples including tumor (T) and adjacent non-tumor (N) tissues. Results The correlation between DNA methylation rate and mRNA expression, together with the correlation between mRNA and protein expression, was calculated. No correlation was observed between any levels using either the measurement value of each sample or the T/N ratio of each pair. Discussion These data suggested that the DNA methylation status of DAPK did not correlate well with its mRNA or protein expression. Extra caution is needed when interpreting the DNA methylation data of DAPK gene in clinical studies

Wear and corrosion resistance of Al1.2CoCrFeNiScx high entropy alloys with scandium addition

The present study focuses on investigating the microstructure, hardness, wear, and corrosion resistance of Al1.2CoCrFeNiScx high entropy alloys, where the Sc content (x) varies between 0, 0.1, 0.2, and 0.3. The results indicate that the addition of Sc promotes the formation of the FCC phase and improves the hardness and wear resistance, but reduces the corrosion resistance of the alloy. The alloy's evolution can be observed as a transition from a single BCC phase to a combination of Fe, Cr-rich BCC phase, Al, Co, Ni-rich BCC phase, and Ni, Sc-rich FCC phase. As the Sc content increases from 0 to 0.3, the hardness increases from 438 HV to 581 HV, representing a 32.6 % increment. This increase can be mainly attributed to grain size strengthening and solid solution strengthening. Additionally, the average friction coefficient experiences a notable reduction from 0.999 to 0.574, indicating a 42.5 % decrease. With respect to wear resistance, the Al1.2CoCrFeNiSc0.3 alloy exhibits superior performance, demonstrated by its lower friction coefficient, reduced wear rate, and smaller volume, width and depth of wear marks. Furthermore, the addition of Sc to the Al1.2CoCrFeNiScx alloys leads to an overall decrease in corrosion potential, accompanied by an increase in corrosion current density, suggesting that Sc has a detrimental effect on the corrosion resistance of the alloy. Moreover, the Al1.2CoCrFeNi alloy displays pitting corrosion, while the Al1.2CoCrFeNiScx alloys demonstrate intercrystalline corrosion, which preferentially occurs on the Ni, Sc-rich phase due to the high electrochemical activity and low equivalent chemical potential

Quantitative and correlation analysis of the DNA methylation and expression of DAPK in breast cancer

Background Death-associated protein kinase 1 (DAPK) is an important tumor suppressor kinase involved in the regulation of multiple cellular activities such as apoptosis and autophagy. DNA methylation of DAPK gene was found in various types of cancers and often correlated with the clinicopathological characteristics. However, the mRNA and protein expression of DAPK in the same sample was rarely measured. Thus, it was unclear if the correlation between DAPK gene methylation and clinicopathological parameters was due to the loss of DAPK expression. Methods In this study, the DNA methylation rate, mRNA and protein expression of DAPK was quantitatively detected in 15 pairs of breast cancer patient samples including tumor (T) and adjacent non-tumor (N) tissues. Results The correlation between DNA methylation rate and mRNA expression, together with the correlation between mRNA and protein expression, was calculated. No correlation was observed between any levels using either the measurement value of each sample or the T/N ratio of each pair. Discussion These data suggested that the DNA methylation status of DAPK did not correlate well with its mRNA or protein expression. Extra caution is needed when interpreting the DNA methylation data of DAPK gene in clinical studies

Comprehensive Evaluation of Quality Traits of Hovenia acerba Germplasm Resources in Fujian Province

Hovenia acerba is a precious medicinal and edible tree. We assessed the genetic variation of H. acerba quality traits and conducted a comprehensive germplasm resource evaluation to provide a theoretical basis for breeding edible, medicinal, and edible/medicine combination varieties. We evaluated 31 H. acerba germplasm resources, including 12 infructescence and 8 fruit quality traits using correlation, principal component, and cluster analyses. The results showed that there were significant differences in all quality traits, with an average coefficient of variation greater than 0.20, an average genetic diversity greater than 1.80, and an average repeatability greater than 0.90. The average genetic variation and repeatability of quality traits in infructescence were higher than fruit. Infructescence K, Ca, Mn, Mg, and reducing sugar contents are important indicators in evaluating infructescence and fruit quality traits, and infructescence K, Mg, and reducing sugar contents are also quality innovation indices of H. acerba germplasms. Tannin, protein, and soluble sugar were the most suitable quality components for screening, followed by reducing sugar, starch, fat, total saponins, and total flavones. According to principal component factor scores and cluster analysis results, specific genotypes were selected as breeding materials for infructescence protein, tannin, flavone, reductive sugar, fruit tannin, fat, flavonoid, saponin, protein, and starch. The correlation analysis with environmental factors showed that the total amount of applied water could influence H. acerba infructescence and fruit quality. In conclusion, the variability of H. acerba germplasm resources was rich, and selection potential is large, which is beneficial to germplasm quality innovation and breeding