Search results for: B. Shen
86 Estimation of Respiratory Parameters in Pressure Controlled Ventilation System with Double Lungs on Secretion Clearance
Authors: Qian Zhang, Dongkai Shen, Yan Shi
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A new mechanical ventilator with automatic secretion clearance function can improve the secretion clearance safely and efficiently. However, in recent modeling studies on various mechanical ventilators, it was considered that human had one lung, and the coupling effect of double lungs was never illustrated. In this paper, to expound the coupling effect of double lungs, a mathematical model of a ventilation system of a bi-level positive airway pressure (BiPAP) controlled ventilator with secretion clearance was set up. Moreover, an experimental study about the mechanical ventilation system of double lungs on BiPAP ventilator was conducted to verify the mathematical model. Finally, the coupling effect of double lungs of the mathematical ventilation was studied by simulation and orthogonal experimental design. This paper adds to previous studies and can be referred to optimization methods in medical researches.Keywords: double lungs, coupling effect, secretion clearance, orthogonal experimental design
Procedia PDF Downloads 60885 Epigenetic Modification Observed in Yeast Chromatin Remodeler Ino80p
Authors: Chang-Hui Shen, Michelle Esposito, Andrew J. Shen, Michael Adejokun, Diana Laterman
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The packaging of DNA into nucleosomes is critical to genomic compaction, yet it can leave gene promoters inaccessible to activator proteins or transcription machinery and thus prevents transcriptional initiation. Both chromatin remodelers and histone acetylases (HATs) are the two main transcription co-activators that can reconfigure chromatin structure for transcriptional activation. Ino80p is the core component of the INO80 remodeling complex. Recently, it was shown that Ino80p dissociates from the yeast INO1 promoter after induction. However, when certain HATs were deleted or mutated, Ino80p accumulated at the promoters during gene activation. This suggests a link between HATs’ presence and Ino80p’s dissociation. However, it has yet to be demonstrated that Ino80p can be acetylated. To determine if Ino80p can be acetylated, wild-type Saccharomyces cerevisiae cells carrying Ino80p engineered with a double FLAG tag (MATa INO80-FLAG his3∆200 leu2∆0 met15∆0 trp1∆63 ura3∆0) were grown to mid log phase, as were non-tagged wild type (WT) (MATa his3∆200 leu2∆0 met15∆0 trp1∆63 ura3∆0) and ino80∆ (MATa ino80∆::TRP1 his3∆200 leu2∆0 met15∆0 trp1∆63 ura3∆0) cells as controls. Cells were harvested, and the cell lysates were subjected to immunoprecipitation (IP) with α-FLAG resin to isolate Ino80p. These eluted IP samples were subjected to SDS-PAGE and Western blot analysis. Subsequently, the blots were probed with the α-FLAG and α-acetyl lysine antibodies, respectively. For the blot probed with α-FLAG, one prominent band was shown in the INO80-FLAG cells, but no band was detected in the IP samples from the WT and ino80∆ cells. For the blot probed with the α-acetyl lysine antibody, we detected acetylated Ino80p in the INO80-FLAG strain while no bands were observed in the control strains. As such, our results showed that Ino80p can be acetylated. This acetylation can explain the co-activator’s recruitment patterns observed in current gene activation models. In yeast INO1, it has been shown that Ino80p is recruited to the promoter during repression, and then dissociates from the promoter once de-repression begins. Histone acetylases, on the other hand, have the opposite pattern of recruitment, as they have an increased presence at the promoter as INO1 de-repression commences. This Ino80p recruitment pattern significantly changes when HAT mutant strains are studied. It was observed that instead of dissociating, Ino80p accumulates at the promoter in the absence of functional HATs, such as Gcn5p or Esa1p, under de-repressing processes. As such, Ino80p acetylation may be required for its proper dissociation from the promoters. The remodelers’ dissociation mechanism may also have a wide range of implications with respect to transcriptional initiation, elongation, or even repression as it allows for increased spatial access to the promoter for the various transcription factors and regulators that need to bind in that region. Our findings here suggest a previously uncharacterized interaction between Ino80p and other co-activators recruited to promoters. As such, further analysis of Ino80p acetylation not only will provide insight into the role of epigenetic modifications in transcriptional activation, but also gives insight into the interactions occurring between co-activators at gene promoters during gene regulation.Keywords: acetylation, chromatin remodeler, epigenetic modification, Ino80p
Procedia PDF Downloads 17084 Hybrid Model for Measuring the Hedge Strategy in Exchange Risk in Information Technology Industry
Authors: Yi-Hsien Wang, Fu-Ju Yang, Hwa-Rong Shen, Rui-Lin Tseng
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The business is notably related to the market risk according to the increase of liberalization of financial markets. Hence, the company usually utilized high financial leverage of derivatives to hedge the risk. When the company choose different hedging instruments to face a variety of exchange rate risk, we employ the Multinomial Logistic-AHP to analyze the impact of various derivatives. Hence, the research summarized the literature on relevant factors affecting managers selected exchange rate hedging instruments, using Multinomial Logistic Model and and further integrate AHP. Using Experts’ Questionnaires can test multi-level selection and hedging effect of different hedging instruments in order to calculate the hedging instruments and the multi-level factors of weights to understand the gap between the empirical results and practical operation. Finally, the Multinomial Logistic-AHP Model will sort the weights to analyze. The research findings can be a basis reference for investors in decision-making.Keywords: exchange rate risk, derivatives, hedge, multinomial logistic-AHP
Procedia PDF Downloads 44283 Modeling of Digital and Settlement Consolidation of Soil under Oedomete
Authors: Yu-Lin Shen, Ming-Kuen Chang
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In addition to a considerable amount of machinery and equipment, intricacies of the transmission pipeline exist in Petrochemical plants. Long term corrosion may lead to pipeline thinning and rupture, causing serious safety concerns. With the advances in non-destructive testing technology, more rapid and long-range ultrasonic detection techniques are often used for pipeline inspection, EMAT without coupling to detect, it is a non-contact ultrasonic, suitable for detecting elevated temperature or roughened e surface of line. In this study, we prepared artificial defects in pipeline for Electromagnetic Acoustic Transducer Testing (EMAT) to survey the relationship between the defect location, sizing and the EMAT signal. It was found that the signal amplitude of EMAT exhibited greater signal attenuation with larger defect depth and length.. In addition, with bigger flat hole diameter, greater amplitude attenuation was obtained. In summary, signal amplitude attenuation of EMAT was affected by the defect depth, defect length and the hole diameter and size.Keywords: EMAT, artificial defect, NDT, ultrasonic testing
Procedia PDF Downloads 33382 The Sexual Knowledge, Attitudes and Behaviors of College Students from Only-Child Families: A National Survey in China
Authors: Jiashu Shen
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This study aims at exploring the characteristics of sexual knowledge, attitudes, and behaviors of Chinese college students from the 'one-child' families compared with those with siblings. This study utilized the data from the 'National College Student Survey on Sexual and Reproductive Health 2019'. Multiple logistic regression analyses were used to assess the association between the 'only-child' and their sexual knowledge, sexual attitudes, sexual behaviors, and risky sexual behaviors (RSB) stratified by sex and home regions, respectively. Compared with students with siblings, the 'only-child' students scored higher in sex-related knowledge (only-child students: 4.49 ± 2.28, students with siblings: 3.60 ± 2.27). Stronger associations between only-child and more liberal sexual attitudes were found in urban areas, including the approval of premarital sexual intercourse (OR: 1.51, 95% CI: 1.50-1.65) and multiple sexual partners (OR: 1.85, 95% CI: 1.72-1.99). For risky sexual behaviors, being only-child is more likely to use condoms in first sexual intercourse, especially among male students (OR: 0.68, 95% CI: 0.58-0.80). Only-child students are more likely to have more sexual knowledge, more liberal sexual attitude, and less risky sexual behavior. Further health policy and sex education should focus more on students with siblings.Keywords: attitudes and behaviors, only-child students, sexual knowledge, students with siblings
Procedia PDF Downloads 18281 A Study on the Influence of Pin-Hole Position Error of Carrier on Mesh Load and Planet Load Sharing of Planetary Gear
Authors: Kyung Min Kang, Peng Mou, Dong Xiang, Gang Shen
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For planetary gear system, Planet pin-hole position accuracy is one of most influential factor to efficiency and reliability of planetary gear system. This study considers planet pin-hole position error as a main input error for model and build multi body dynamic simulation model of planetary gear including planet pin-hole position error using MSC. ADAMS. From this model, the mesh load results between meshing gears in each pin-hole position error cases are obtained and based on these results, planet load sharing factor which reflect equilibrium state of mesh load sharing between whole meshing gear pair is calculated. Analysis result indicates that the pin-hole position error of tangential direction cause profound influence to mesh load and load sharing factor between meshing gear pair.Keywords: planetary gear, load sharing factor, multibody dynamics, pin-hole position error
Procedia PDF Downloads 57980 Post Occupancy Evaluation of the Green Office Building with Different Air-Conditioning Systems
Authors: Ziwei Huang, Jian Ge, Jie Shen, Jiantao Weng
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Retrofitting of existing buildings plays a critical role to achieve sustainable development. This is being considered as one of the approaches to achieving sustainability in the built environment. In order to evaluate the different air-conditioning systems effectiveness and user satisfaction of the existing building which had transformed into green building effectively and accurately. This article takes the green office building in Zhejiang province, China as an example, analyzing the energy consumption, occupant satisfaction and indoor environment quality (IEQ) from the perspective of the thermal environment. This building is special because it combines ground source heat pump system and Variable Refrigerant Flow (VRF) air-conditioning system. Results showed that the ground source heat pump system(EUIa≈25.6) consumes more energy than VRF(EUIb≈23.8). In terms of a satisfaction survey, the use of the VRF air-conditioning was more satisfactory in temperature. However, the ground source heat pump is more satisfied in air quality.Keywords: post-occupancy evaluation, green office building, air-conditioning systems, ground source heat pump system
Procedia PDF Downloads 19679 Design Study for the Rehabilitation of a Retaining Structure and Water Intake on Site
Authors: Yu-Lin Shen, Ming-Kuen Chang
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In addition to a considerable amount of machinery and equipment, intricacies of the transmission pipeline exist in Petrochemical plants. Long term corrosion may lead to pipeline thinning and rupture, causing serious safety concerns. With the advances in non-destructive testing technology, more rapid and long-range ultrasonic detection techniques are often used for pipeline inspection, EMAT without coupling to detect, it is a non-contact ultrasonic, suitable for detecting elevated temperature or roughened e surface of line. In this study, we prepared artificial defects in pipeline for Electromagnetic Acoustic Transducer testing (EMAT) to survey the relationship between the defect location, sizing and the EMAT signal. It was found that the signal amplitude of EMAT exhibited greater signal attenuation with larger defect depth and length. In addition, with bigger flat hole diameter, greater amplitude attenuation was obtained. In summary, signal amplitude attenuation of EMAT was affected by the defect depth, defect length and the hole diameter and size.Keywords: EMAT, artificial defect, NDT, ultrasonic testing
Procedia PDF Downloads 35078 China's Middle East Policy and the Competition with the United States
Authors: Shabnam Dadparvar, Laijin Shen
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This paper focuses on China’s policy in the Middle East and the rivalry with the U.S. The question is that what are the main factors on China’s Middle East policy and its competition with the U.S? The hypothesis regards to three effective factors: 'China’s energy dependency' on the Middle East, 'economy' and support for 'stability' in the Middle East. What is important in China’s competition with the U.S regarding to its Middle East policy is the substantial difference in ways of treating the countries of the region; China is committed to Westphalia model based on non-interference in internal affairs of the countries and respect the sovereignty of the governments. However, after 9/11, the U.S is seeking a balance between stability and change through intervention in the international affairs and in some cases is looking for a regime change. From the other hand, China, due to its dependency on the region’s energy welcomes America’s military presence in the region for providing stability. The authors by using a descriptive analytical method try to explain the situation of rivalry between China and the United States in Middle East. China is an 'emerging power' with high economic growth and in demand of more energy supply. The problem is that a rising power in the region is often a source of concern for hegemony.Keywords: China's foreign policy, energy, hegemony, the Middle East
Procedia PDF Downloads 35277 Photon Blockade in Non-Hermitian Optomechanical Systems with Nonreciprocal Couplings
Authors: J. Y. Sun, H. Z. Shen
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We study the photon blockade at exceptional points for a non-Hermitian optomechanical system coupled to the driven whispering-gallery-mode microresonator with two nanoparticles under the weak optomechanical coupling approximation, where exceptional points emerge periodically by controlling the relative angle of the nanoparticles. We find that conventional photon blockade occurs at exceptional points for the eigenenergy resonance of the single-excitation subspace driven by a laser field and discuss the physical origin of conventional photon blockade. Under the weak driving condition, we analyze the influences of the different parameters on conventional photon blockade. We investigate conventional photon blockade at nonexceptional points, which exists at two optimal detunings due to the eigenstates in the single-excitation subspace splitting from one (coalescence) at exceptional points to two at nonexceptional points. Unconventional photon blockade can occur at nonexceptional points, while it does not exist at exceptional points since the destructive quantum interference cannot occur due to the two different quantum pathways to the two-photon state not being formed. The realization of photon blockade in our proposal provides a viable and flexible way for the preparation of single-photon sources in the non-Hermitian optomechanical system.Keywords: optomechanical systems, photon blockade, non-hermitian, exceptional points
Procedia PDF Downloads 14076 Microstructural and Mechanical Characterization of a 16MND5 Steel Manufactured by Innovative WAAM SAW Process
Authors: F. Villaret, I. Jacot, Y. Shen, Z. Kong, T. XU, Y. Wang, D. Lu
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Wire Arc Additive Manufacturing (WAAM) allows the rapid production of large, homogeneous parts with complex geometry. However, in the nuclear field, parts can reach dimensions of ten to a hundred tons. In this case, the usual WAAM TIG or CMT processes do not have sufficient deposition rates to consider the manufacture of parts of such dimensions within a reasonable time. The submerged arc welding process (SAW, Submerged Arc Welding) allows much higher deposition rates. Although there are very few references to this process for additive manufacturing in the literature, it has been used for a long time for the welding and coating of nuclear power plant vessels, so this process is well-known and mastered as a welding process. This study proposes to evaluate the SAW process as an additive manufacturing technique by taking as an example a low-alloy steel of type 16MND5. In the first step, a parametric study allowed the evaluation of the effect of the different parameters and the deposition rate on the geometry of the beads and their microstructure. Larger parts were also fabricated and characterized by metallography and mechanical tests (tensile, impact, toughness). The effect of different heat treatments on the microstructure is also studied.Keywords: WAAM, low alloy steel, submerged arc, caracterization
Procedia PDF Downloads 8475 Investigating the Properties of Asphalt and Asphalt Mixture Based on the Effect of Waste Toner
Authors: Prince Igor Itoua, Daquan Sun, Shihui Shen
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This study aimed at investigating the properties of asphalt and mix asphalt based on the effects of waste toner sources (WT1 and WT2) with 8% dosage waste toner powders (WT). The test results included penetration, softening points, ductility, G*sinδ, G*/sinδ, Ideal cracking test(IDEAL-CT), and Ideal shear rutting test(IDEAL-RT). The results showed that the base binder with WT2 had a significantly higher viscosity value compared to the WT1 modified binder, and thus, higher energy for mixing and compaction is needed. Fur-thermore, the results of penetration, softening points, G*sinδ, and G*/sinδ were all affected by waste toner type. In terms of asphalt mixture, the IDEAL-RT test revealed that the addition of waste toner improved the rutting resistance of the asphalt mixture regardless of toner type. Further, CTindex values for waste toner-modified asphalt mixtures show no significant difference. Above all, WT-modified asphalt mixtures produced by the wet process have better rutting performance.Keywords: waste toner, waste toner modified asphalt, asphalt mixture properties, IDEAL-RT test, IDEAL-CT test
Procedia PDF Downloads 8774 A Global Fuel Combustion Data Product and Its Application
Authors: Shu Tao, Rong Wang, Huizhong Shen, Ye Huang
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High-resolution mapping of fuel combustion is essential for reducing uncertainties in assessments of greenhouse gases and air pollutant emissions. Such inventories provide valuable information for inferring carbon sinks, modeling pollutant transport, and developing control strategies. Previous inventories included only a few fuel types and were derived using national population proxies which may distort the geographical variation within countries. In this study, a global 0.1 degree by 0.1 degree geo-referenced inventory of fuel combustion (PKU-FUEL-2007) was developed for 64 fuel sub-types along with uncertainty analysis for the year 2007. Sub-national fuel consumption of large countries and major power-station locations were used. The disaggregation error can be reduced significantly by using the sub-nationally energy data, because the uneven distribution of per-capita fuel consumption within countries is taken into consideration. The PKU-FUEL was used to generate global emission inventories of CO2 (PKU-CO2-2007), polycyclic aromatic hydrocarbons (PKU-PAHs-2007), and black carbons (PKU-BC-2007). Atmospheric transport modeling and expsoure assessment were conducted for BC and PAHs based on the inventory.Keywords: fuel, emission, BC, PAHs, atmospheric transport, exposure
Procedia PDF Downloads 32973 Study of Electro Magnetic Acoustic Transducer to Detect Flaw in Pipeline
Authors: Yu-Lin Shen, Ming-Kuen Chang
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In addition to a considerable amount of machinery and equipment, intricacies of the transmission pipeline exist in Petrochemical plants. Long term corrosion may lead to pipeline thinning and rupture, causing serious safety concerns. With the advances in non-destructive testing technology, more rapid and long-range ultrasonic detection techniques are often used for pipeline inspection, EMAT without coupling to detect, it is a non-contact ultrasonic, suitable for detecting elevated temperature or roughened e surface of line. In this study, we prepared artificial defects in pipeline for Electro Magnetic Acoustic Transducer Testing (EMAT) to survey the relationship between the defect location, sizing and the EMAT signal. It was found that the signal amplitude of EMAT exhibited greater signal attenuation with larger defect depth and length.. In addition, with bigger flat hole diameter, greater amplitude attenuation was obtained. In summary, signal amplitude attenuation of EMAT was affected by the defect depth, defect length and the hole diameter and size.Keywords: EMAT, NDT, artificial defect, ultrasonic testing
Procedia PDF Downloads 47572 Towards a Biologically Inspired Supercritical Airfoil Adapted for Gliding Cross-Domain Vehicles
Authors: Hanyue Shen, Jiaying Zhang, Xingwei Kong
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Growing research on cross-domain vehicles (CDVs) has addressed the requirement to balance airfoil efficiency in air and water. No existing airfoil is specifically developed to adapt to the large Reynold’s number range CDVs operate in. This research proposes a supercritical airfoil biologically inspired by Atlantic Puffins. The initial airfoil is parameterized with the composite Karman-Trefftz method, optimized with a series of multi-stage gradient descend procedures, and compared with other airfoils with Xfoil. Results from Xfoil are also validated via Fluent and experiment considering curvatures on the designed airfoil might affect the accuracy of Xfoil. The results indicate that while CFD and Xfoil results closely align, Xfoil produces results closest to the experimental value. The bionic airfoil demonstrates superior performance in the range Re = 2·10⁴ to Re = 2·10⁵ compared to other studied airfoils, satisfying design requirements. This airfoil and its future counterparts are probable solutions to be implemented on fixed-wing CDVs desiring to glide in the given working conditions, providing an efficient and structurally simple pathway.Keywords: fluid dynamics, airfoil design, biomimicry, cross domain vehicle
Procedia PDF Downloads 5071 The Integrated Urban Strategies Based on Deep Urban History and Modern Technology Study: Tourism and Leisure Industries as Driving Force to Reactivate Historical Area
Authors: Cheng Li, Jie Shen, Yutian Tang
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Embracing the upcoming era of urbanization with the challenges of limitation of resources, disappearing cultural identities and conflicts among different groups of stakeholders, new integrated approaches are offered in our urban practice to help decision-makers and stakeholders frame and develop well-conceived, practical strategies for urban developing trajectories to approach urban-level sustainability in multiple social, cultural, ecological dimensions. Through bottom-up participation, we take advantage of tourism and leisure industries as driving forces for urbanization in China to promote integrated sustainable systems, with the hope of approaching both historical and ecological aspects of urban sustainability; and also thanks to top-down participation, we have codes, standards and rules established by the governments to strengthen the implementation of ecological urban sustainability. The results are monitored and evaluated experimentally and multidimensionally and the sustainable systems we constructed with local stakeholder groups turned out to be effective. The presentation of our selected projects would indicate our different focuses on urban sustainability.Keywords: urban sustainability, integrated urban strategy, tourism and leisure industries, history, modern technology
Procedia PDF Downloads 38170 Operator Optimization Based on Hardware Architecture Alignment Requirements
Authors: Qingqing Gai, Junxing Shen, Yu Luo
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Due to the hardware architecture characteristics, some operators tend to acquire better performance if the input/output tensor dimensions are aligned to a certain minimum granularity, such as convolution and deconvolution commonly used in deep learning. Furthermore, if the requirements are not met, the general strategy is to pad with 0 to satisfy the requirements, potentially leading to the under-utilization of the hardware resources. Therefore, for the convolution and deconvolution whose input and output channels do not meet the minimum granularity alignment, we propose to transfer the W-dimensional data to the C-dimension for computation (W2C) to enable the C-dimension to meet the hardware requirements. This scheme also reduces the number of computations in the W-dimension. Although this scheme substantially increases computation, the operator’s speed can improve significantly. It achieves remarkable speedups on multiple hardware accelerators, including Nvidia Tensor cores, Qualcomm digital signal processors (DSPs), and Huawei neural processing units (NPUs). All you need to do is modify the network structure and rearrange the operator weights offline without retraining. At the same time, for some operators, such as the Reducemax, we observe that transferring the Cdimensional data to the W-dimension(C2W) and replacing the Reducemax with the Maxpool can accomplish acceleration under certain circumstances.Keywords: convolution, deconvolution, W2C, C2W, alignment, hardware accelerator
Procedia PDF Downloads 10469 A Study on the Influence of Planet Pin Parallelism Error to Load Sharing Factor
Authors: Kyung Min Kang, Peng Mou, Dong Xiang, Yong Yang, Gang Shen
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In this paper, planet pin parallelism error, which is one of manufacturing error of planet carrier, is employed as a main variable to influence planet load sharing factor. This error is categorize two group: (i) pin parallelism error with rotation on the axis perpendicular to the tangent of base circle of gear(x axis rotation in this paper) (ii) pin parallelism error with rotation on the tangent axis of base circle of gear(y axis rotation in this paper). For this study, the planetary gear system in 1.5MW wind turbine is applied and pure torsional rigid body model of this planetary gear is built using Solidworks and MSC.ADAMS. Based on quantified parallelism error and simulation model, dynamics simulation of planetary gear is carried out to obtain dynamic mesh load results with each type of error and load sharing factor is calculated with mesh load results. Load sharing factor formula and the suggestion for planetary reliability design is proposed with the conclusion of this study.Keywords: planetary gears, planet load sharing, MSC. ADAMS, parallelism error
Procedia PDF Downloads 39968 Suppression of DMBA/TPA-Induced Skin Tumorigenesis by Menthol through Inhibition of Inflammation, NF-kappaB, Ras-Raf-ERK Pathway
Authors: Zhaoguo Liu, Cunsi Shen, Yin Lu
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Growing evidence has shown that menthol has potent anticancer activity in various human cancers. However, its effect on skin cancer remains largely unknown. In the present study, we investigated the chemopreventive potential of menthol against 7, 12-dimethylbenz[a] anthracene(DMBA)/12-O-tetradecanoylphorbol 13-acetate (TPA)-induced skin tumorigenesis in ICR mice. Our results showed that menthol significantly inhibited TPA-induced inflammatory responses and pro-inflammatory cytokine release. We also found that menthol treatment significantly inhibited TPA-induced lipid peroxidation (LPO), mouse UDP-glucumno-syltransferase (UGT), mouse NADH Dehydrogenase, Quinone 1 (NQO1) release. Furthermore, we found menthol treatment significantly inhibited the tumor incidence and number of tumors (P < 0.001). Interestingly, we observed that menthol treatment significantly inhibited TPA-induced altered activity of NF-κB in skin tumor. Consistently, menthol-treated tumors also showed significantly suppressed the Ras-Raf-ERK signaling pathway. Thus, our results suggest that menthol inhibits DMBA/TPA-induced skin tumorigenesis by attenuating the Ras and inhibiting NF-κB activity via inhibition of inflammation responses and pro-inflammatory cytokine release.Keywords: DMBA/TPA, NF-κB, Ras-Raf-ERK, skin tumorigenesis
Procedia PDF Downloads 31367 An Improved Method on Static Binary Analysis to Enhance the Context-Sensitive CFI
Authors: Qintao Shen, Lei Luo, Jun Ma, Jie Yu, Qingbo Wu, Yongqi Ma, Zhengji Liu
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Control Flow Integrity (CFI) is one of the most promising technique to defend Code-Reuse Attacks (CRAs). Traditional CFI Systems and recent Context-Sensitive CFI use coarse control flow graphs (CFGs) to analyze whether the control flow hijack occurs, left vast space for attackers at indirect call-sites. Coarse CFGs make it difficult to decide which target to execute at indirect control-flow transfers, and weaken the existing CFI systems actually. It is an unsolved problem to extract CFGs precisely and perfectly from binaries now. In this paper, we present an algorithm to get a more precise CFG from binaries. Parameters are analyzed at indirect call-sites and functions firstly. By comparing counts of parameters prepared before call-sites and consumed by functions, targets of indirect calls are reduced. Then the control flow would be more constrained at indirect call-sites in runtime. Combined with CCFI, we implement our policy. Experimental results on some popular programs show that our approach is efficient. Further analysis show that it can mitigate COOP and other advanced attacks.Keywords: contex-sensitive, CFI, binary analysis, code reuse attack
Procedia PDF Downloads 32366 Enhanced High-Temperature Strength of HfNbTaTiZrV Refractory High-Entropy Alloy via Al₂O₃ Reinforcement
Authors: Bingjie Wang, Qianqian Qang, Nan Lu, Xiubing Liang, Baolong Shen
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Novel composites of HfNbTaTiZrV refractory high-entropy alloy (RHEA) reinforced with 0-5 vol.% Al₂O₃ particles have been synthesized by vacuum arc melting. The microstructure evolution, compressive mechanical properties at room and elevated temperatures, as well as strengthening mechanism of the composites, are analyzed. The HfNbTaTiZrV RHEA reinforced with 4 vol.% Al₂O₃ displays excellent phase stability at elevated temperatures. A superior compressive yield strength of 2700 MPa at room temperature, 1392 MPa at 800 °C, and 693 MPa at 1000 °C has been obtained for this composite. The improved yield strength results from multiple strengthening mechanisms caused by Al₂O₃ addition, including interstitial strengthening, grain boundary strengthening, and dispersion strengthening. Besides, the effects of interstitial strengthening increase with the temperature and is the main strengthening mechanism at elevated temperatures. These findings not only promote the development of oxide-reinforced RHEAs for challenging engineering applications but also provide guidelines for the design of light refractory materials with multiple strengthening mechanisms.Keywords: Al₂O₃-reinforcement, HfNbTaTiZrV, refractory high-entropy alloy, interstitial strengthening
Procedia PDF Downloads 11465 The Associations of Family Support with Sexual Behaviour and Repeat Induced Abortion among Chinese Adolescents
Authors: Jiashu Shen
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Background: The abortion rate has increased significantly, which is harmful especially to adolescents, making repeat induced abortion (RIA) among adolescents a social problem. This study aims to investigate the associations of family support with sexual behavior and repeat induced abortion among Chinese adolescents Methods: This study based on a national hospital-based sample with 945 girls aged 15-19 who underwent induced abortion in 43 hospitals. Multivariate logistic regressions were performed to estimated odds ratio for the risk factors. Results: Adolescences living with parents were less inclined to undergo RIA, especially if they were rural (adjusted odds ratio=0.48 95%CI 0.31-0.72) and local (adjusted odds ratio =0.39 95%=0.23-0.66). Those with parental financial support were likely to have less sexual partnersand take contraceptives more regularly. Those with higher self-perceived importance in family were more likely to take contraceptives during the first sexual intercourse in higher age, and with higher first abortion age and less sexual partners. Conclusion: In mainland China, living with parents, parental financial support, high self-perceived importance in family and adequate family sexuality communications may contribute to lower incidence of RIA.Keywords: Chinese adolescent, family support, repeat induced abortion, sexual behavior
Procedia PDF Downloads 12064 Commodification of the Chinese Language: Investigating Language Ideology in the Chinese Complementary Schools’ Online Discourse
Authors: Yuying Liu
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Despite the increasing popularity of Chinese and the recognition of the growing commodifying ideology of Chinese language in many contexts (Liu and Gao, 2020; Guo, Shin and Shen 2020), the ideological orientations of the Chinese diaspora community towards the Chinese language remain under-researched. This research contributes seeks to bridge this gap by investigating the micro-level language ideologies embedded in the Chinese complementary schools in the Republic of Ireland. Informed by Ruíz’s (1984) metaphorical representations of language, 11 Chinese complementary schools’ websites were analysed as discursive texts that signal the language policy and ideology to prospective learners and parents were analysed. The results of the analysis suggest that a move from a portrayal of Chinese as linked to student heritage identity, to the commodification of linguistic and cultural diversity, is evident. It denotes the growing commodifying ideology among the Chinese complementary schools in the Republic of Ireland. The changing profile of the complementary school, from serving an ethnical community to teaching Chinese as a foreign language for the wider community, indicates the possibility of creating the a positive synergy between the Complementary school and the mainstream education. This study contributes to the wider discussions of language ideology and language planning, with regards to modern language learning and heritage language maintenance.Keywords: the Chinese language;, Chinese as heritage language, Chinese as foreign language, Chinese community schools
Procedia PDF Downloads 13563 Numerical Study on the Performance of Upgraded Victorian Brown Coal in an Ironmaking Blast Furnace
Authors: Junhai Liao, Yansong Shen, Aibing Yu
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A 3D numerical model is developed to simulate the complicated in-furnace combustion phenomena in the lower part of an ironmaking blast furnace (BF) while using pulverized coal injection (PCI) technology to reduce the consumption of relatively expensive coke. The computational domain covers blowpipe-tuyere-raceway-coke bed in the BF. The model is validated against experimental data in terms of gaseous compositions and coal burnout. Parameters, such as coal properties and some key operational variables, play an important role on the performance of coal combustion. Their diverse effects on different combustion characteristics are examined in the domain, in terms of gas compositions, temperature, and burnout. The heat generated by the combustion of upgraded Victorian brown coal is able to meet the heating requirement of a BF, hence making upgraded brown coal injected into BF possible. It is evidenced that the model is suitable to investigate the mechanism of the PCI operation in a BF. Prediction results provide scientific insights to optimize and control of the PCI operation. This model cuts the cost to investigate and understand the comprehensive combustion phenomena of upgraded Victorian brown coal in a full-scale BF.Keywords: blast furnace, numerical study, pulverized coal injection, Victorian brown coal
Procedia PDF Downloads 24362 Anti-Obesity Effect of Cordyceps militaris Fermented Black Rice
Authors: Chih-Hung Liang, Jung-Jung Chen, Shen-Shih Chiang
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Obesity is defined as abnormal or excessive fat accumulation that presents a risk to health, which are major risk factors for a number of chronic diseases, including diabetes, cardiovascular diseases and cancer. Cordyceps militaris (CM) is a well-known traditional medicine in Asian countries and a rich source of biologically active components. Black rice (Oryza sativa L.) is a special cultivar of rice that contains rich anthocyanins and regarded as a health-promoting food in China and other Eastern. The aim of this study was to investigate the anti-obesity effect of Cordyceps militaris fermented black rice (CB) on HFD-induced BALB/c mice model. The results indicated that administration of low and high dosage of CB powder significantly reduced the body weights (7.38% and 7.78%), body fat ratio (2.37% and 2.78%), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels compared to the HF group (p<0.05). Histopathological analysis showed that the score of fatty liver in HF group (5.0) was significantly higher than CB groups (2.1 and 3.6) (p<0.05). In conclusion, Cordyceps militaris fermented black rice can reduce the body weight via inhibition of the fat accumulation in liver and body and possess the anti-obesity potency.Keywords: Cordyceps militaris, black rice, obesity, HFD-induced mice
Procedia PDF Downloads 31061 Self-Attention Mechanism for Target Hiding Based on Satellite Images
Authors: Hao Yuan, Yongjian Shen, Xiangjun He, Yuheng Li, Zhouzhou Zhang, Pengyu Zhang, Minkang Cai
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Remote sensing data can provide support for decision-making in disaster assessment or disaster relief. The traditional processing methods of sensitive targets in remote sensing mapping are mainly based on manual retrieval and image editing tools, which are inefficient. Methods based on deep learning for sensitive target hiding are faster and more flexible. But these methods have disadvantages in training time and cost of calculation. This paper proposed a target hiding model Self Attention (SA) Deepfill, which used self-attention modules to replace part of gated convolution layers in image inpainting. By this operation, the calculation amount of the model becomes smaller, and the performance is improved. And this paper adds free-form masks to the model’s training to enhance the model’s universal. The experiment on an open remote sensing dataset proved the efficiency of our method. Moreover, through experimental comparison, the proposed method can train for a longer time without over-fitting. Finally, compared with the existing methods, the proposed model has lower computational weight and better performance.Keywords: remote sensing mapping, image inpainting, self-attention mechanism, target hiding
Procedia PDF Downloads 13660 Synergy and Complementarity in Technology-Intensive Manufacturing Networks
Authors: Daidai Shen, Jean Claude Thill, Wenjia Zhang
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This study explores the dynamics of synergy and complementarity within city networks, specifically focusing on the headquarters-subsidiary relations of firms. We begin by defining these two types of networks and establishing their pivotal roles in shaping city network structures. Utilizing the mesoscale analytic approach of weighted stochastic block modeling, we discern relational patterns between city pairs and determine connection strengths through statistical inference. Furthermore, we introduce a community detection approach to uncover the underlying structure of these networks using advanced statistical methods. Our analysis, based on comprehensive network data up to 2017, reveals the coexistence of both complementarity and synergy networks within China’s technology-intensive manufacturing cities. Notably, firms in technology hardware and office & computing machinery predominantly contribute to the complementarity city networks. In contrast, a distinct synergy city network, underpinned by the cities of Suzhou and Dongguan, emerges amidst the expansive complementarity structures in technology hardware and equipment. These findings provide new insights into the relational dynamics and structural configurations of city networks in the context of technology-intensive manufacturing, highlighting the nuanced interplay between synergy and complementarity.Keywords: city system, complementarity, synergy network, higher-order network
Procedia PDF Downloads 4359 Male Versatile Sexual Offenders in Taiwan
Authors: Huang Yueh Chen, Sheng Ang Shen
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Purpose: Sexual assault has always been a highly anticipated crime in Taiwan. People assume that the career of sexual offenders tends to be highly specialized. This study hopes to analyze the crime career and risk factors of offenders by means of another classification. Methods: A total of 145 sexual offenders were sentenced on the parole or expiration date from 2009 to 2011, through analysis of official existing documents such as ‘Re-infringement risk assessment report’ and ‘case assessment report’. Results: The section ‘Various Types of Crimes ‘ of criminal career is analyzed. The highest number of ‘ versatile sexual offender’ followed by ‘adult sexual offender’ is about 2.5, representing more than 1.5 kinds of non-sex crimes besides sexual crimes. Different specialized sexual offenders have had extensive experience in the ‘Sexual Assault Experiences in Children and School’, ‘Static 99 Levels’, ‘Pre-Commuted Substance Use’, ‘Excited Deviant Sexual Behavior’, ‘Various Types of Crimes,’ and ‘Sexual Crime in Forerunner’ , ‘Type of Index Crime’ and other projects to achieve significant differences. Conclusions: Resources continue to be devoted to specialized offenders, the character of first-time sexual offender depends on further research and makes the public aware of the different assumptions of diversified offenders from traditional professional offenses that reduce unnecessary panic in society.Keywords: versatile sexual offender, specialized sexual offender, criminal career, risk factor
Procedia PDF Downloads 16658 Effect of the Tooling Conditions on the Machining Stability of a Milling Machine
Authors: Jui-Pui Hung, Yong-Run Chen, Wei-Cheng Shih, Shen-He Tsui, Kung-Da Wu
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This paper presents the effect on the tooling conditions on the machining stabilities of a milling machine tool. The machining stability was evaluated in different feeding direction in the X-Y plane, which was referred as the orientation-dependent machining stability. According to the machining mechanics, the machining stability was determined by the frequency response function of the cutter. Thus, we first conducted the vibration tests on the spindle tool of the milling machine to assess the tool tip frequency response functions along the principal direction of the machine tool. Then, basing on the orientation dependent stability analysis model proposed in this study, we evaluated the variation of the dynamic characteristics of the spindle tool and the corresponding machining stabilities at a specific feeding direction. Current results demonstrate that the stability boundaries and limited axial cutting depth of a specific cutter were affected to vary when it was fixed in the tool holder with different overhang length. The flute of the cutter also affects the stability boundary. When a two flute cutter was used, the critical cutting depth can be increased by 47 % as compared with the four flute cutter. The results presented in study provide valuable references for the selection of the tooling conditions for achieving high milling performance.Keywords: tooling condition, machining stability, milling machine, chatter
Procedia PDF Downloads 43157 Electronic/Optoelectronic Property Tuning in Two-Dimensional Transition Metal Dichalcogenides via High Pressure
Authors: Juan Xia, Jiaxu Yan, Ze Xiang Shen
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The tuneable interlayer interactions in two-dimensional (2D) transition metal dichlcogenides (TMDs) offer an exciting platform for exploring new physics and applications by material variety, thickness, stacking sequence, electromagnetic filed, and stress/strain. Compared with the five methods mentioned above, high pressure is a clean and powerful tool to induce dramatic changes in lattice parameters and physical properties for 2D TMD materials. For instance, high pressure can strengthen the van der Waals interactions along c-axis and shorten the covalent bonds in atomic plane, leading to the typical first-order structural transition (2Hc to 2Ha for MoS2), or metallization. In particular, in the case of WTe₂, its unique symmetry endows the significant anisotropy and the corresponding unexpected properties including the giant magnetoresistance, pressure-induced superconductivity and Weyl semimetal states. Upon increasing pressure, the Raman peaks for WTe₂ at ~120 cm⁻¹, are gradually red-shifted and totally suppressed above 10 GPa, attributed to the possible structural instability of orthorhombic Td phase under high pressure and phase transition to a new monoclinic T' phase with inversion symmetry. Distinct electronic structures near Fermi level between the Td and T' phases may pave a feasible way to achieve the Weyl state tuning in one material without doping.Keywords: 2D TMDs, electronic property, high pressure, first-principles calculations
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