Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
134
result(s) for
"Du, Xiang-yang"
Sort by:
Microstructure evolution of 7050 Al alloy fasteners during cold upsetting after equal channel angular pressing
by
He, Tao
,
Du, Xiang-yang
,
Vereshchaka, Aleksey
in
Accumulation
,
Aluminum base alloys
,
Banded structure
2023
The innovative combination of equal channel angular pressing (ECAP) and cold upsetting (CU) is significant for producing high-strength Al alloy fasteners with ultrafine grains. However, the relationship between microstructure evolution and mechanical strength during composite deformation remains unclear. In this study, using transmission electron microscopy, electron backscatter diffraction, and mechanical property tests, it is found that the mechanical strength increases with each step of composite forming operations due to the accumulation of dislocations. Forest dislocations also contribute to the generation of ultrafine grains within deformed grains, particularly in ECAP-CU processed grains. Moreover, we observe the formation of lamellar structures within the shear bands in the head of the ultrafine grain fastener after final composite deformation, which is full of dense dislocation walls and dislocation cells. The rearrangement of these fine grains and lamellar structures yield a strong (011) (brass) texture during composite deformation under the effect of shear force and accumulation of plastic strain. This study provides a theoretical reference for the manufacture of high-strength aluminum alloy fasteners through composite deformation and helps improve processing technology.
Journal Article
A High-Temperature Strain-Compensated Arrhenius-Type Constitutive Model and an Improved Avrami-Type Dynamic Recrystallization Model of 40CrNiMo
by
Yuan-ming, Huo
,
Chang-yuan, Jia
,
Tao, He
in
Characterization and Evaluation of Materials
,
Chemistry and Materials Science
,
Constitutive models
2024
The flow stress of a metallic material is one of the important parameters to measure the plastic deformability of a material. The quality of the microstructure reflects the forming quality and reliability of a part. Therefore, a high-quality flow stress and microstructure models are very important for the optimization of the process parameters. The flow stress and dynamic recrystallization (DRX) law of the 40CrNiMo axle steel were obtained by performing a thermal simulation compression test and metallography examination. The effects of deformation temperatures, strain rates, and initial grain sizes on the DRX and flow curves were discussed. A strain-compensated Arrhenius-type flow stress equation was established. Considering the influence of the deformation temperatures, strain rates, and initial grain sizes on DRX, a kinetic model and an average grain size evolution model for DRX were established. Statistical and finite element (FE) simulation methods were used to verify the predictability and validity of the flow stress and the microstructure models, which provides an important basis for the study of hot forming of the 40CrNiMo steel.
Journal Article
Test Point Switch in Low Voltage Electrical Transient Performances Detection Technical Improvement Methods
2013
This article introduces, in low voltage circuit breaker on the switch instantaneous performance detecting station, in order to adapt to the requirement of modern high-speed automated production test, the main factors affecting the detection speed - switch measurement point method is studied, the improvement, the existing method of \"contact switch\" to replace \"non-contact switch method, through theoretical derivation and experimental proof, proved that the new method is feasible and economical.
Journal Article
Spatial-temporal pattern changes of main agriculture natural disasters in China during 1990-2011
by
DU Xindong JIN Xiaobin YANG Xilian YANG Xuhong XIANG Xiaomin
in
Agricultural development
,
Agriculture
,
Disasters
2015
China is a disaster prone country, and a comprehensive understanding of change of disasters is very important for China's agricultural development. In this study, statistical tech niques and geographic information system tools are employed to quantify the main agricul ture disasters changes and effects on grain production in China during the period of 1990-2011. The results show that China's grain production was severely affected by disas ters including drought, flood, hail, frost and typhoon. The annual area covered by these dis asters reached up to 48.7x106 ha during the study period, which accounted for 44.8% of the total sown area, and about 55.1% of the per unit area grain yield change was caused by disasters. In addition, all of the disasters showed high variability, different changing trends, and spatial distribution. Drought, flood, and hail showed significantly decreasing trends, while frost and typhoon showed increasing trends. Drought and flood showed gradual changes and were distributed across the country, and disasters became more diversified from north to south. Drought was the dominated disaster type in northern China, while flood was the most important disaster type in the southern part. Hail was mainly observed in central and northern China, and frost was mainly distributed in southern China. Typhoon was greatly limited to the southeast coast. Furthermore, the resilience of grain production of each province was quite different, especially in several major grain producing areas, such as Shandong, Liaoning, Jilin and Jiangsu, where grain production was seriously affected by disasters. One reason for the difference of resilience of grain production was that grain production was marginalized in developed provinces when the economy underwent rapid development. For China's agricul tural development and grain security, we suggest that governments should place more em phasis on grain production, and invest more money in disaster prevention and mitigation, especially in the major grain producing provinces.
Journal Article
Inhibition of soluble epoxide hydrolase attenuates renal tubular mitochondrial dysfunction and ER stress by restoring autophagic flux in diabetic nephropathy
2020
Diabetic nephropathy (DN) is the leading cause of end-stage renal disease (ESRD), and renal tubular cell dysfunction contributes to the pathogenesis of DN. Soluble epoxide hydrolase (sEH) is an enzyme that can hydrolyze epoxyeicosatrienoic acids (EETs) and other epoxy fatty acids (EpFAs) into the less biologically active metabolites. Inhibition of sEH has multiple beneficial effects on renal function, however, the exact role of sEH in hyperglycemia-induced dysfunction of tubular cells is still not fully elucidated. In the present study, we showed that human proximal tubular epithelial (HK-2) cells revealed an upregulation of sEH expression accompanied by the impairment of autophagic flux, mitochondrial dysfunction, ubiquitinated protein accumulation and enhanced endoplasmic reticulum (ER) stress after high glucose (HG) treatment. Furthermore, dysfunctional mitochondria accumulated in the cytoplasm, which resulted in excessive reactive oxygen species (ROS) generation, Bax translocation, cytochrome c release, and apoptosis. However,
t
-AUCB, an inhibitor of sEH, partially reversed these negative outcomes. Moreover, we also observed increased sEH expression, impaired autophagy flux, mitochondrial dysfunction and enhanced ER stress in the renal proximal tubular cells of db/db diabetic mice. Notably, inhibition of sEH by treatment with
t
-AUCB attenuated renal injury and partially restored autophagic flux, improved mitochondrial function, and reduced ROS generation and ER stress in the kidneys of db/db mice. Taken together, these results suggest that inhibition of sEH by
t
-AUCB plays a protective role in hyperglycemia-induced proximal tubular injury and that the potential mechanism of
t
-AUCB-mediated protective autophagy is involved in modulating mitochondrial function and ER stress. Thus, we provide new evidence linking sEH to the autophagic response during proximal tubular injury in the pathogenesis of DN and suggest that inhibition of sEH can be considered a potential therapeutic strategy for the amelioration of DN.
Journal Article
CD147-spike protein is a novel route for SARS-CoV-2 infection to host cells
2020
In face of the everlasting battle toward COVID-19 and the rapid evolution of SARS-CoV-2, no specific and effective drugs for treating this disease have been reported until today. Angiotensin-converting enzyme 2 (ACE2), a receptor of SARS-CoV-2, mediates the virus infection by binding to spike protein. Although ACE2 is expressed in the lung, kidney, and intestine, its expressing levels are rather low, especially in the lung. Considering the great infectivity of COVID-19, we speculate that SARS-CoV-2 may depend on other routes to facilitate its infection. Here, we first discover an interaction between host cell receptor CD147 and SARS-CoV-2 spike protein. The loss of CD147 or blocking CD147 in Vero E6 and BEAS-2B cell lines by anti-CD147 antibody, Meplazumab, inhibits SARS-CoV-2 amplification. Expression of human CD147 allows virus entry into non-susceptible BHK-21 cells, which can be neutralized by CD147 extracellular fragment. Viral loads are detectable in the lungs of human CD147 (hCD147) mice infected with SARS-CoV-2, but not in those of virus-infected wild type mice. Interestingly, virions are observed in lymphocytes of lung tissue from a COVID-19 patient. Human T cells with a property of ACE2 natural deficiency can be infected with SARS-CoV-2 pseudovirus in a dose-dependent manner, which is specifically inhibited by Meplazumab. Furthermore, CD147 mediates virus entering host cells by endocytosis. Together, our study reveals a novel virus entry route, CD147-spike protein, which provides an important target for developing specific and effective drug against COVID-19.
Journal Article
Scavenger receptor-A is a biomarker and effector of rheumatoid arthritis: A large-scale multicenter study
2020
Early diagnosis is critical to improve outcomes in rheumatoid arthritis (RA), but current diagnostic tools have limited sensitivity. Here we report a large-scale multicenter study involving training and validation cohorts of 3,262 participants. We show that serum levels of soluble scavenger receptor-A (sSR-A) are increased in patients with RA and correlate positively with clinical and immunological features of the disease. This discriminatory capacity of sSR-A is clinically valuable and complements the diagnosis for early stage and seronegative RA. sSR-A also has 15.97% prevalence in undifferentiated arthritis patients. Furthermore, administration of SR-A accelerates the onset of experimental arthritis in mice, whereas inhibition of SR-A ameliorates the disease pathogenesis. Together, these data identify sSR-A as a potential biomarker in diagnosis of RA, and targeting SR-A might be a therapeutic strategy.
Scavenger receptor-A (SR-A) is mostly expressed by myeloid cells and has been attributed a variety of biological functions. Here the authors assess SR-A as a biomarker for diagnosis of rheumatoid arthritis (RA) using large-scale training and validation cohorts and show that modulating SR-A levels can alter progression of collagen-induced arthritis in mice.
Journal Article
Association of socioeconomic and lifestyle factors with prevalence of diabetes in rural southwest China: a structural equation modelling approach
2024
ObjectivesThis study aimed to investigate the prevalence of diabetes using structural equation modelling (SEM) to examine the pathways and associations of socioeconomic and lifestyle factors on diabetes in rural southwest China.DesignData were collected from a cross-sectional health interview and examination survey among individuals aged ≥35 years in rural southwest China. Fasting blood glucose, blood pressure, height, weight and waist circumference (WC) were measured for each participant. SEM was employed to assess the relationships between demographic characteristics (sex, age and ethnicity), socioeconomic position (SEP; annual household income, education level and access to medical services), lifestyle factors (obesity status (body mass index and WC) and physical inactivity), hypertension, hyperlipidaemia and family history of diabetes.SettingThis study was conducted in rural Yunnan Province of China.Participants7536 individuals aged ≥35 years consented to participate in the study.ResultsThe overall prevalence of diabetes in the present study was 8.3%. Prevalence did not differ by gender (prevalence for both men and women was 8.3% (p>0.05)). The results of SEM indicated that SEP, age, ethnicity, obesity status and physical inactivity had both significant direct and indirect effects on diabetes, with total effect size of 0.091, 0.149, –0.094, 0.212 and 0.089, respectively (p<0.01). Family history of diabetes (0.128, p<0.01), hypertension (0.135, p<0.01) and hyperlipidaemia (0.137, p<0.01) were directly associated with diabetes.ConclusionsSocioeconomic and lifestyle factors have both direct and indirect effects on prevalence of diabetes in rural southwest China. Future efforts to implement comprehensive interventions to promote the prevention and control of diabetes should in particular focus on obese individuals.
Journal Article
Green pepper fruits counting based on improved DeepSort and optimized Yolov5s
2024
Green pepper yield estimation is crucial for establishing harvest and storage strategies.
This paper proposes an automatic counting method for green pepper fruits based on object detection and multi-object tracking algorithm. Green pepper fruits have colors similar to leaves and are often occluded by each other, posing challenges for detection. Based on the YOLOv5s, the CS_YOLOv5s model is specifically designed for green pepper fruit detection. In the CS_YOLOv5s model, a Slim-Nick combined with GSConv structure is utilized in the Neck to reduce model parameters while enhancing detection speed. Additionally, the CBAM attention mechanism is integrated into the Neck to enhance the feature perception of green peppers at various locations and enhance the feature extraction capabilities of the model.
According to the test results, the CS_YOLOv5s model of mAP, Precision and Recall, and Detection time of a single image are 98.96%, 95%, 97.3%, and 6.3 ms respectively. Compared to the YOLOv5s model, the Detection time of a single image is reduced by 34.4%, while Recall and mAP values are improved. Additionally, for green pepper fruit tracking, this paper combines appearance matching algorithms and track optimization algorithms from SportsTrack to optimize the DeepSort algorithm. Considering three different scenarios of tracking, the MOTA and MOTP are stable, but the ID switch is reduced by 29.41%. Based on the CS_YOLOv5s model, the counting performance before and after DeepSort optimization is compared. For green pepper counting in videos, the optimized DeepSort algorithm achieves ACP (Average Counting Precision), MAE (Mean Absolute Error), and RMSE (Root Mean Squared Error) values of 95.33%, 3.33, and 3.74, respectively. Compared to the original algorithm, ACP increases by 7.2%, while MAE and RMSE decrease by 6.67 and 6.94, respectively. Additionally, Based on the optimized DeepSort, the fruit counting results using YOLOv5s model and CS_YOLOv5s model were compared, and the results show that using the better object detector CS_YOLOv5s has better counting accuracy and robustness.
Journal Article
Exploration into Natural Variation Genes Associated with Determinate and Capitulum-like Inflorescence in Brassica napus
2023
Brassica napus is a globally important vegetable and oil crop. The research is meaningful for the yield and plant architecture of B. napus. In this study, one natural mutant line with determinate and capitulum-like inflorescence was chosen for further study. Genetic analysis indicated that the segregation patterns of inflorescences in the F2 populations supported a digenic inheritance model, which was further approved via the BSA-Seq technique. The BSA-Seq method detected two QTL regions on C02 (14.27–18.41 Mb) and C06 (32.98–33.68 Mb) for the genetic control of determinate inflorescences in MT plants. In addition, the expression profile in MT compared with WT was analyzed, and a total of 133 candidate genes for regulating the flower development (75 genes, 56.4%), shoot meristem development (29 genes, 21.8%), and inflorescence meristem development (13 genes, 9.8%) were identified. Then one joint analysis combing BSA-Seq and RNA-Seq identified two candidate genes of BnaTFL1 and BnaAP1 for regulating the MT phenotype. Furthermore, the potential utilization of the MT plants was also discussed.
Journal Article