DYNAMIC MODELING OF BRAKE IN POWER-SPLIT DHT AND PRESSURE TRACKING CONTROL WITH SLIDING MODE VARIABLE STRUCTURE METHOD

Zhiguo Zhao,Mengna Li,Chen Wang,Lanxing Jiang,Maoyao Wang 한국자동차공학회 2019 International journal of automotive technology Vol.20 No.3

Since the mode transition performance of power-split DHT (Dedicated Hybrid Transmission) are directly influenced by torque dynamic characteristic of the brake, the brake pressure should be controlled accurately. In this paper, a dynamic model of brake and its pressure regulating system are established by considering system nonlinear characteristics and input disturbances, and a sliding mode variable structure controller is developed to track the brake pressure. First, the operation principle of DHT's pressure regulating system is introduced. Second, the dynamic models of solenoid proportional pressure valve, electromagnetic direction switching valve and brake are established with AMESim parametric plant model. Furthermore, a sliding mode variable structure controller for tracking pressure is designed based on MATLAB/Simulink. Finally, the AMESim parametric plant model is validated by measurements, and the proposed controller are verified by AMESim and Simulink co-simulation. The results show that the system dynamics can be well characterized by the AMESim parametric plant model. The target pressure can be tracked rapidly and accurately by using sliding mode variable structure controller and the controller has better robustness.

KH₂PO₄-aided soil washing for removing arsenic from water-stable soil aggregates collected in southern China

Ranran Zhao,Xiaojun Li,Zhiguo Zhang,Guanghui Zhao 대한환경공학회 2016 Environmental Engineering Research Vol.21 No.3

Removal of arsenic (As) from soil aggregates with particle sizes of > 2.0, 2.0-0.25, 0.25-0.053, < 0.053 mm by soil washing of KH₂PO₄ and the kinetics of As releasing from soil aggregates were investigated. Effects of KH₂PO₄ concentration, ratio of liquid/soil and washing duration on the removal were fully explored. The results showed that the high As removal was obtained in > 2 mm aggregates (48.56%) and < 0.053 mm aggregates (42.88%) under the optimum condition (KH₂PO₄ concentration of 0.1 mol/L, and liquid/soil ratio (10 mL/g) for 360 min). 62.82% of As was extracted from aggregates with size less than 0.25 mm. Only 11.88% was contributed by the large aggregates (> 2.0mm). Using KH₂PO₄ washing, it was also found that extracted As is mainly in form of either specifically sorbed As or As associated with oxides of Fe and Al. Elovich model can describe the removal process of As more precisely than Two-constant kinetic models. The optimum washing conditions and removal process is also applied to bulk soil. This technique in this study is reliable, cost-effective and offers a great potential for practical application in soil remediation.

Analytical Prediction for Tunnel-Soil-Pile Interaction Mechanics based on Kerr Foundation Model

Zhiguo Zhang,Chengping Zhang,Kangming Jiang,Zhiwei Wang,Yunjuan Jiang,Qihua Zhao,Minghao Lu 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.6

Existing analytical method to predict tunneling-induced pile deformation is generally based on the Winkler foundation model that neglects shear effects of soil, which is not sufficient for engineering practice. A simplified solution based on Kerr foundation model is presented in this study to investigate the tunnel-soil-pile interaction. In order to improve the accuracy of the prediction for tunneling-induced free-field movements, the cavity contraction theory is utilized in the first stage which received a higher accuracy than the previous solution. In the second stage, the soil free-field displacement is imposed on the existing pile, and the simplified solution for pile deformation governed by the disturbance of passive displacement is established based on the Kerr foundation model, which can take account of the soil shear effects. The applicability and accuracy of the simplified solution are then verified by several cases including the reported analytical solution, centrifuge modeling tests and observed data in situ. Good agreements are obtained in the comparative analyses, which demonstrates that the proposed solution can serve as an alternative approach for conservatively estimating tunneling-induced pile deformation in the preliminary design in clay. Furthermore, the parametric analysis associated with the pile deformation has also been performed. As a result, it is of primarily theoretical and practical significance to investigate the influence of soil shear effects on the tunnel-soil-pile interaction mechanics.

Assessment Method of Slope Excavation Quality based on Point Cloud Data

Zhiguo Pan,Yihong Zhou,Chunju Zhao,Chao Hu,Huawei Zhou,Yong Fan 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.3

Slope excavation quality assessment is essential in water conservancy engineering. This study presents a quality assessment method to estimate the excavation quality of a slope based on point cloud data obtained from a 3D Terrestrial Laser Scanner (TLS). A data processing method, which includes coordinate registration, data partitioning, and noise removal, is proposed to organize raw data from the TLS and ensure accurate and available point cloud data of a slope surface. An excavation quality assessment method with seven indicators, namely, slope ratio, slope toe elevation, back break, volume of back break, remained semi-void rate, unevenness, and offset degree, is proposed to analyze the difference between a slope’s as-design excavation appearance and actual construction appearance. The as-design excavation appearance is expressed by the Building Information Modeling (BIM) model of a slope-excavation face, and it is a reference to assess the actual construction appearance. The slope excavation quality of a water conservancy project in southwest China is evaluated with the proposed method and the traditional method. The results demonstratethat the proposed method can estimate the slope excavation quality effectively, rapidly, and accuately, and can provide theoretical data support for subsequent work.

Interaction Analyses between Existing Pipeline and Quasi-Rectangular Tunneling in Clays

Zhiguo Zhang,Mengxi Zhang,Qihua Zhao,Lei Fang,Zhi Ding,Minzhi Shi 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.1

Previous researches about geoenvironmental disturbance caused by tunneling have mainly concentrated on the influences of circular tunnel construction, but minimal interesting is given to the quasi-rectangular shield tunneling. Considering the convergence deformation model for quasi-rectangular shield tunneling at excavation face, the simplified closed-form solution is put forward to evaluate the deformation behavior for underground pipeline caused by quasi-rectangular shield tunneling. Firstly, the free-field displacements induced by the quasi-rectangular shield excavation are estimated by the point source technique. Secondly, characterized by the Winkler foundation, the free-field displacements are applied to the pipeline structures and a simplified analytical solution is obtained for analyzing the deformation of adjacent pipeline induced by quasi-rectangular tunneling. Through the analyses of engineering cases, the comparison between analytical solution for the free-field deformation and measured data is conducted. Meanwhile, the numerical simulation technique and the physical modelling tests for the pipeline deformation are utilized to compare the simplified analytical results. In addition, the primary parameters are conducted for the interaction mechanics between quasi-rectangular tunneling and existing pipeline, such as the pipeline diameter, the geometry size and centerline depth of pipeline and tunnel, the structural physics modulus of pipeline, the compressive modulus of ground, and the ground loss parameter. The results of this study are of great significance for exploring the geomechanical effects induced by quasi-rectangular shield tunneling in clays.

Antioxidant Mechanism and Lipid Peroxidation Patterns in Leaves and Petals of Marigold in Response to Drought Stress

Zhiguo Tian,Fei Wang,Wene Zhang,Changming Liu,Xiuming Zhao 한국원예학회 2012 Horticulture, Environment, and Biotechnology Vol.53 No.3

In this study, malondialdehyde (MDA), relative conductivity (RC), superoxide anion (O2・-), hydrogen peroxide (H2O2), superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX) as well as ascorbic acid (AsA), glutation (GSH) and carotenoid (Car) were analyzed in plants under drought condition to investigate the enzymatic and non-enzymatic antioxidant defense mechanisms of leaves and petals, respectively. Two different drought resistance marigold cultivars (Tagetes erecta L. cv. Chokdee and Tagetes erecta L. cv. Discovery)treated with 6-day drought stress were used at early flowering stage. Results indicated that drought treatment increased MDA, RC, O2・- and H2O2 contents in the two cultivars, especially in drought-sensitive cultivar ‘Discovery’. In contrast,‘Chokdee’ had higher level antioxidative enzyme activities and more non-enzymatic antioxidants than those in ‘Discovery’. SOD, POD, CAT, APX activities and non-enzymatic antioxidants (GSH and AsA) in the leaves and petals were increased at the beginning treatment, and decreased later. The activity of CAT in leaves and petals, APX in petals and AsA in petals on day 6 after treatment were lower than those in control, while Car in the two cultivars decreased consistently during drought stress treatment. In addition, all the antioxidant enzyme activities in the leaves were higher than those in petals, but AsA and GSH were accumulated at lower levels in leaves than those in petals of the both cultivars. Furthermore, significant linear relationships were found between antioxidative enzymes and reactive oxygen species (ROS), as well as in non-enzymatic antioxidants and ROS. In conclusion, drought tolerance of ‘Chokdee’ was correlated with eliminating the O2・- and H2O2 and maintaining lower lipid peroxidation as well as higher membrane stability by increasing activities of antioxidative enzymes and the amount of non-enzymatic antioxidants. Furthermore, different drought response mechanisms were involved in leaves and petals of marigold under drought stress.

Severe choline deficiency induces alternative splicing aberrance in optimized duck primary hepatocyte cultures

Zhao Lulu,Cai Hongying,Wu Yongbao,Tian Changfu,Wen Zhiguo,Yang Peilong 아세아·태평양축산학회 2022 Animal Bioscience Vol.35 No.11

Objective: Choline deficiency, one main trigger for nonalcoholic fatty liver disease (NAFLD), is closely related to lipid metabolism disorder. Previous study in a choline-deficient model has largely focused on gene expression rather than gene structure, especially sparse are studies regarding to alternative splicing (AS). In modern life science research, primary hepatocytes culture technology facilitates such studies, which can accurately imitate liver activity in vitro and show unique superiority. Whereas limitations to traditional hepatocytes culture technology exist in terms of efficiency and operability. This study pursued an optimization culture method for duck primary hepatocytes to explore AS in choline-deficient model. Methods: We performed an optimization culture method for duck primary hepatocytes with multi-step digestion procedure from Pekin duck embryos. Subsequently a NAFLD model was constructed with choline-free medium. RNA-seq and further analysis by rMATS were performed to identify AS events alterations in choline-deficency duck primary hepatocytes. Results: The results showed E13 (embryonic day 13) to E15 is suitable to obtain hepatocytes, and the viability reached over 95% by trypan blue exclusion assay. Primary hepatocyte retained their biological function as well identified by Periodic Acid-Schiff staining method and Glucose-6-phosphate dehydrogenase activity assay, respectively. Meanwhile, genes of alb and afp and specific protein of albumin were detected to verify cultured hepatocytes. Immunofluorescence was used to evaluate purity of hepatocytes, presenting up to 90%. On this base, choline-deficient model was constructed and displayed significantly increase of intracellular triglyceride and cholesterol as reported previously. Intriguingly, our data suggested that AS events in choline-deficient model were implicated in pivotal biological processes as an aberrant transcriptional regulator, of which 16 genes were involved in lipid metabolism and highly enriched in glycerophospholipid metabolism. Conclusion: An effective and rapid protocol for obtaining duck primary hepatocytes was established, by which our findings manifested choline deficiency could induce the accumulation of lipid and result in aberrant AS events in hepatocytes, providing a novel insight into various AS in the metabolism role of choline. Objective: Choline deficiency, one main trigger for nonalcoholic fatty liver disease (NAFLD), is closely related to lipid metabolism disorder. Previous study in a choline-deficient model has largely focused on gene expression rather than gene structure, especially sparse are studies regarding to alternative splicing (AS). In modern life science research, primary hepatocytes culture technology facilitates such studies, which can accurately imitate liver activity <i>in vitro</i> and show unique superiority. Whereas limitations to traditional hepatocytes culture technology exist in terms of efficiency and operability. This study pursued an optimization culture method for duck primary hepatocytes to explore AS in choline-deficient model.Methods: We performed an optimization culture method for duck primary hepatocytes with multi-step digestion procedure from Pekin duck embryos. Subsequently a NAFLD model was constructed with choline-free medium. RNA-seq and further analysis by rMATS were performed to identify AS events alterations in choline-deficency duck primary hepatocytes.Results: The results showed E13 (embryonic day 13) to E15 is suitable to obtain hepatocytes, and the viability reached over 95% by trypan blue exclusion assay. Primary hepatocyte retained their biological function as well identified by Periodic Acid-Schiff staining method and Glucose-6-phosphate dehydrogenase activity assay, respectively. Meanwhile, genes of <i>alb</i> and <i>afp</i> and specific protein of albumin were detected to verify cultured hepatocytes. Immunofluorescence was used to evaluate purity of hepatocytes, presenting up to 90%. On this base, choline-deficient model was constructed and displayed significantly increase of intracellular triglyceride and cholesterol as reported previously. Intriguingly, our data suggested that AS events in choline-deficient model were implicated in pivotal biological processes as an aberrant transcriptional regulator, of which 16 genes were involved in lipid metabolism and highly enriched in glycerophospholipid metabolism.Conclusion: An effective and rapid protocol for obtaining duck primary hepatocytes was established, by which our findings manifested choline deficiency could induce the accumulation of lipid and result in aberrant AS events in hepatocytes, providing a novel insight into various AS in the metabolism role of choline.

Subproteomic profiling from renal cortices in OLETF rats reveals mutations of multiple novel genes in diabetic nephropathy

Li Zhiguo,Shen Hong,Liu Yeqiang,Zhou Xuefeng,Yan Meihua,He Hailan,Zhao Tingting,Zhang Haojun,Li Ping 한국유전학회 2022 Genes & Genomics Vol.44 No.1

Background: Ovarian cancer is a common gynecological malignancy among female patients and poses a serious threat to women's health. Although it has been established that Fos-like antigen 2 (FOSL2) is linked to ovarian cancer (OC), its exact role in the development of OC remains unknown. Objective: This article aims to investigate the role of FOSL2 in ovarian cancer development. Methods: FOSL2 expression in ovarian carcinoma and adjacent tissues was assessed using real-time fluorescent quantitative PCR and western blot. We constructed OE/sh-FOSL2 plasmids and Caspase-1 specific inhibitors (Yvad-CMK) and transfected A 2780 cells with them to identify the relevant cell functions. Furthermore, we used western blot assay to determine the changes in expression of apoptosis-associated speck-like protein containing a CARD (ASC), cysteine aspartate-specific proteasezymogen procaspase 1 (pro-caspase-1), cysteinyl aspartate-specific proteinase-1 (caspase-1), interleukin-1β precursor (pro-IL-1β), interleukin-1β (IL-1β), interleukin-18 precursor (pro-IL-18), and interleukin-18 (IL-18). In addition, we measured the concentration of IL-1β and IL-18 using an enzyme-linked immunosorbent assay (ELISA). Moreover, Tthe level of lactate dehydrogenase (LDH) in the cell supernatant was measured by LDH release assay kit. Results: The expression of FOSL2 was significantly higher compared with the surrounding tissues. The proliferation, migration, and invasion of A2780 cells were enhanced after transfection with OE-FOSL2 plasmids; however, the cell apoptosis was significantly decreased. When FOSL2 was overexpressed, the inflammasome-associated proteins such as ASC, caspase-1, IL-1β, and IL-18 were downregulated. Furthermore, FOSL2 induced apoptosis and activated the production of inflammasomes in A2780 cells. Co-therapy with Yvad-CMK and substantially inhibited apoptosis and activation of inflammasomes. Conclusions: Inhibition of FOSL2 promotes the apoptosis of OC cells by mediating the formation of an inflammasome.

Environmental factors have a strong impact on the composition and diversity of the gut bacterial community of Chinese black honeybees

Yazhou Zhao,Yanping Chen,Zhiguo Li,Wenjun Peng 한국응용곤충학회 2018 Journal of Asia-Pacific Entomology Vol.21 No.1

Acetylcholinesterase (AChE) plays a pivotal role in synaptic transmission by hydrolyzing the neurotransmitteracetylcholine. In addition to the classical function of AChE in synaptic transmission, various non-classicalfunctions have been elucidated. Unlike vertebrates possessing a single AChE gene (ace), invertebrates (nematodes,arachnids, and insects) have multiple ace loci, encoding diverse AChEs with a range of different functions. In the field of toxicology, AChE with synaptic function has long been exploited as the target of organophosphorusand cabarmate pesticides to control invertebrate pests for the past several decades. However, many aspects of theevolution and non-classical roles of invertebrate AChEs are still unclear. Although currently available informationon invertebrate AChEs is fragmented, we reviewed the recent findings on their evolutionary status,molecular/biochemical properties, and deduced non-classical (non-neuronal) functions. The Chinese black honeybees is an ecotype of the European honeybee that is formed by the natural hybridizationof Apis mellifera mellifera and A. m. carnica. It is distributed in nature reserves in North China and has been animportant breeding resource for disease resistance and other desirable traits. Compared to the areas outside ofreserves, the nature reserves offer significant biodiversity benefits not only to the Chinese black honey bees butalso to the other valuable plants and animals. In recent years there has been growing evidence that environmentalfactors including food choices play an important role in shaping the composition and activity of gutmicrobiota, which in turn can impact host health. In the previous studies on Chinse black honeybees, littleattention has been paid to the diverse population of microbes in the gut that play a vital role in host health. Inorder to achieve a better understanding on the role of environmental factors in diversity and composition of gutmicrobiota of honey bees, in the present study, we analyzed the gut bacterial communities of Chinese blackhoneybees using terminal restriction fragment length polymorphism (T-RFLP). The results showed that thesamples from the national nature reserves that are protected and managed so as to preserve and enrich theirnatural condition and resources for Chinese black honeybees had higher variety and richness of gut bacteria thanthat collected from unreserved regions that also harbor populations of Chinese black honeybees. The fourterminal restriction fragments (T-RFs), 201, 223, 247 and 320 bp, were identified to be the dominant bacteria ofChinese black honeybees. Of which 247 and 320 bp had greater differences between bee groups sampled indifferent regions and therefore could be used as genetic markers to separate samples collected from the nationalnature reserves to samples collected from unreserved regions. The results clearly indicate that national naturereserve protects biological diversity and ecological and evolutionary processes which have had a significantinfluence on the diversity of gut bacteria of Chinese black honeybees. The ubiquity of gut symbiotic bacteriaidentified in Chinese black honeybee suggests that environmental factors could play an important role in diversityand composition of gut bacteria and warrant further investigation into the functional significance of thesegut bacteria for the honeybee health.

High expression of RAD51 promotes DNA damage repair and survival in KRAS-mutant lung cancer cells

( Jinfang Hu ),( Zhiguo Zhang ),( Lei Zhao ),( Li Li ),( Wei Zuo ),( Lei Han ) 생화학분자생물학회(구 한국생화학분자생물학회) 2019 BMB Reports Vol.52 No.2

RAD51 recombinase plays a critical role in homologous recombination and DNA damage repair. Here we showed that expression of RAD51 is frequently upregulated in lung cancer tumors compared with normal tissues and is associated with poor survival (hazard ratio (HR) = 2, P = 0.0009). Systematic investigation of lung cancer cell lines revealed higher expression of RAD51 in KRAS mutant (MT) cells compared to wildtype (WT) cells. We further showed that MT KRAS, but not WT KRAS, played a critical role in RAD51 overexpression via MYC. Moreover, our results revealed that KRAS MT cells are highly dependent on RAD51 for survival and depletion of RAD51 resulted in enhanced DNA double strand breaks, defective colony formation and cell death. Together, our results suggest that mutant KRAS promotes RAD51 expression to enhance DNA damage repair and lung cancer cell survival, suggesting that RAD51 may be an effective therapeutic target to overcome chemo/radioresistance in KRAS mutant cancers. [BMB Reports 2019; 52(2): 151-156]