Search results for: Ling Chen
1210 Alleviation of Endoplasmic Reticulum Stress in Mosquito Cells to Survive Dengue 2 Virus Infection
Authors: Jiun-Nan Hou, Tien-Huang Chen, Wei-June Chen
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Dengue viruses (DENVs) are naturally transmitted between humans by mosquito vectors. Mosquito cells usually survive DENV infection, allowing infected mosquitoes to retain an active status for virus transmission. In this study, we found that DENV2 virus infection in mosquito cells causes the unfolded protein response (UPR) that activates the protein kinase RNA-like endoplasmic reticulum kinase (PERK) signal pathway, leading to shutdown of global protein translation in infected cells which was apparently regulated by the PERK signal pathway. According to observation in this study, the PERK signal pathway in DENV2-infected C6/36 cells alleviates ER stress, and reduces initiator and effector caspases, as well as the apoptosis rate via shutdown of cellular proteins. In fact, phosphorylation of eukaryotic initiation factor 2ɑ (eIF2ɑ) by the PERK signal pathway may impair recruitment of ribosomes that bind to the mRNA 5’-cap structure, resulting in an inhibitory effect on canonical cap-dependent cellular protein translation. The resultant pro-survival “byproduct” of infected mosquito cells is undoubtedly advantageous for viral replication. This finding provides insights into elucidating the PERK-mediated modulating web that is actively involved in dynamic protein synthesis, cell survival, and viral replication in mosquito cells.Keywords: cap-dependent protein translation, dengue virus, endoplasmic reticulum stress, mosquito cells, PERK signal pathway
Procedia PDF Downloads 2601209 Surface Sensing of Atomic Behavior of Polymer Nanofilms via Molecular Dynamics Simulation
Authors: Ling Dai
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Surface-sensing devices such as atomic force microscope have been widely used to characterize the surface structure and properties of nanoscale polymer films. However, using molecular dynamics simulations, we show that there is intrinsic and unavoidable inelastic deformation at polymer surfaces induced by the sensing tip. For linear chain polymers like perfluoropolyether, such tip-induced deformation derives from the differences in the atomic interactions which are atomic specie-based Van der Waals interactions, and resulting in atomic shuffling and causing inelastic alternation in both molecular structures and mechanical properties at the regions of the polymer surface. For those aromatic chain polymers like epoxy, the intrinsic deformation is depicted as the intra-chain rotation of aromatic rings and kinking of linear atomic connections. The present work highlights the need to reinterpret the data obtained from surface-sensing tests by considering this intrinsic inelastic deformation occurring at polymer surfaces.Keywords: polymer, surface, nano, molecular dynamics
Procedia PDF Downloads 3471208 Nutrients Removal Control via an Intermittently Aerated Membrane Bioreactor
Authors: Junior B. N. Adohinzin, Ling Xu
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Nitrogen is among the main nutrients encouraging the growth of organic matter and algae which cause eutrophication in water bodies. Therefore, its removal from wastewater has become a worldwide emerging concern. In this research, an innovative Membrane Bioreactor (MBR) system named “moving bed membrane bioreactor (MBMBR)” was developed and investigated under intermittently-aerated mode for simultaneous removal of organic carbon and nitrogen. Results indicated that the variation of the intermittently aerated duration did not have an apparent impact on COD and NH4+–N removal rate, yielding the effluent with average COD and NH4+–N removal efficiency of more than 92 and 91% respectively. However, in the intermittently aerated cycle of (continuously aeration/0s mix), (aeration 90s/mix 90s) and (aeration 90s/mix 180s); the average TN removal efficiency was 67.6%, 69.5% and 87.8% respectively. At the same time, their nitrite accumulation rate was 4.5%, 49.1% and 79.4% respectively. These results indicate that the intermittently aerated mode is an efficient way to controlling the nitrification to stop at nitrition; and also the length of anoxic duration is a key factor in improving TN removal.Keywords: membrane bioreactor (MBR), moving bed biofilm reactor (MBBR), nutrients removal, simultaneous nitrification and denitrification
Procedia PDF Downloads 3401207 Impact of Education on Levels of Physical Activity and Depression in Taiwanese Vegetarians and Omnivores
Authors: Ya-Lin Chang, Chia Chen Chang, Yu-Ru Liang, Joyce Chen, You-Kang Chang, Tina Chiu
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Physical activity and mental health status are important for health. The purpose of this study was to examine levels of physical activities and depression in Taiwanese vegetarians (VEG) and omnivores (OMNI). Sixty-three vegetarians (20 males) and 56 omnivores (23 males) with an average age of 51 years were recruited for a food frequency validation study at Taipei Tzu Chi Hospital from July to September in 2016. Participants filled out a validated Chinese version international physical activity questionnaire-short-form (IPAQ), Beck Depression Inventory-II-Chinese version (BDI), food frequency questionnaire (FFQ) and a questionnaire on demographics and medical history upon recruitment. Total BDI scores were calculated for depression and the metabolic equivalent of task (MET) was calculated for physical activity levels. Mann-Whitney U tests and Chi-square test were used to compare demographics, physical activity levels and depression scores. VEG and OMNI did not differ significantly on MET (1441.9 ± 3387.3 vs. 1605.8 ± 2486.1. p=0.2652, respectively). VEG scored slightly lower on BDI compared to OMNI without statistical significance (5.6 ± 5.7 vs. 7.4 ± 6.3. p=0.06). In addition, we found that regardless of diet practice, those who held a college degree and above scored better on MET (1788.1 ± 2532.6 vs. 1215.5 ± 3425.5. p=0.0014) and BDI (5.2 ± 5.1 vs. 7.8 ± 6.7. p=0.03). In this cross-sectional study, Taiwanese vegetarians and omnivores scored comparatively on physical activity levels and depression. However, education is a significant determinant of physical activity and depression.Keywords: BDI, diet, education, physical activity
Procedia PDF Downloads 3841206 Effects of Cinnamon, Garlic, and Yucca Extracts on Growth Performance and Serum Biochemical Parameters in Broilers
Authors: Anguo Chen, Huajie Chen, Caimei Yang, Qihua Hong, Jun Feng
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The experiment was conducted with 360 one-day-old Avian commercial broilers to study the effects of dietary cinnamon extract (CE), garlic extract (GE) and yucca extract (YE) on growth performance and serum biochemical parameters in broilers. The chickens were randomly divided equally into 4 treatment groups, each group with 3 replications, and received the same basal corn-bean diets included a starter from 1 d to 21 d and then a grower until 42 d, added with recommended dose 250 mg/kg CE, 25 mg/kg GE and 10 mg/kg YE to relevant group, respectively. The birds were kept in a stainless steel net coop each replication with 24 h light and were fed and drunk ad libitum. At 21 d and 42 d of age, 6 chicks were respectively picked out from every group and were bled to collect serum samples and intestinal samples for laboratory analysis. The results showed that the average daily gain (ADG) of CE, GE and YE group were increased by 7.20% (P<0.05), 3.43% (P>0.05) and 4.89% (P>0.05), feed gain ratio (F/G) was improved by 9.71% (P<0.05), 3.40% (P>0.05) and 3.40% (P>0.05) compared with the control, respectively. At 21 d of age, the content of serum urea nitrogen (SUN) and serum uric acid (SUA) and the activity of serum xanthine oxidase (SXO) in CE group were reduced by 35.17% (P<0.01), 13.73% (P<0.01) and 16.33% (P<0.05) compared with the control, respectively. At 42 d of age, SUN and SUA level and SXO activity were lowered by 24.35% (P<0.01), 15.49% (P<0.05) and 23.09% (P<0.01), respectively. The SXO activity in CE group was decreased by 14.86% (P<0.01) and 15.34%(P<0.01) compare with GE and YE group, respectively. Also, adding CE, GE and YE into broiler diets resulted in lower UN and UA level of intestinal contents. It is clear that CE was more significantly decreased the SXO activity and SUA levels than GE and YE, especially at the latter period, thereby it may play a more important role in improving the growth performance of broilers.Keywords: cinnamon extract, broiler, growth performance, serum uric acid, serum xanthine oxidase
Procedia PDF Downloads 4331205 Experimental Study on Performance of a Planar Membrane Humidifier for a Proton Exchange Membrane Fuel Cell Stack
Authors: Chen-Yu Chen, Wei-Mon Yan, Chi-Nan Lai, Jian-Hao Su
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The proton exchange membrane fuel cell (PEMFC) becomes more important as an alternative energy source recently. Maintaining proper water content in the membrane is one of the key requirements for optimizing the PEMFC performance. The planar membrane humidifier has the advantages of simple structure, low cost, low-pressure drop, light weight, reliable performance and good gas separability. Thus, it is a common external humidifier for PEMFCs. In this work, a planar membrane humidifier for kW-scale PEMFCs is developed successfully. The heat and mass transfer of humidifier is discussed, and its performance is analyzed in term of dew point approach temperature (DPAT), water vapor transfer rate (WVTR) and water recovery ratio (WRR). The DPAT of the humidifier with the counter flow approach reaches about 6°C under inlet dry air of 50°C and 60% RH and inlet humid air of 70°C and 100% RH. The rate of pressure loss of the humidifier is 5.0×10² Pa/min at the torque of 7 N-m, which reaches the standard of commercial planar membrane humidifiers. From the tests, it is found that increasing the air flow rate increases the WVTR. However, the DPAT and the WRR are not improved by increasing the WVTR as the air flow rate is higher than the optimal value. In addition, increasing the inlet temperature or the humidity of dry air decreases the WVTR and the WRR. Nevertheless, the DPAT is improved at elevated inlet temperatures or humidities of dry air. Furthermore, the performance of the humidifier with the counter flow approach is better than that with the parallel flow approach. The DPAT difference between the two flow approaches reaches up to 8 °C.Keywords: heat and mass transfer, humidifier performance, PEM fuel cell, planar membrane humidifier
Procedia PDF Downloads 3021204 A Ti₃C₂O₂ Supported Single Atom, Trifunctional Catalyst for Electrochemical Reactions
Authors: Zhanzhao Fu, Chongyi Ling, Jinlan Wang
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Water splitting and rechargeable air-based batteries are emerging as new renewable energy storage and conversion technologies. However, the discovery of suitable catalysts with high activity and low cost remains a great challenge. In this work, we report a single-atom trifunctional catalyst, namely Ti₃C₂O₂ supported single Pd atom (Pd1@Ti₃C₂O₂), for the hydrogen evolution reaction (HER), oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). This catalyst is selected from 12 candidates and possesses low overpotentials of 0.22 V, 0.31 V and 0.34 V for the HER, OER and ORR, respectively, making it an excellent electrocatalyst for both overall water splitting and rechargeable air-based batteries. The superior OER and ORR performance originates from the optimal d band center of the supported Pd atom. Moreover, the excellent activity can be maintained even if the single Pd atoms aggregate into small clusters. This work offers new opportunities for advancing the renewable energy storage and conversion technologies and paves a new way for the development of multifunctional electrocatalysts.Keywords: DFT, SACs, OER, ORR, HER
Procedia PDF Downloads 701203 Observation of the Orthodontic Tooth's Long-Term Movement Using Stereovision System
Authors: Hao-Yuan Tseng, Chuan-Yang Chang, Ying-Hui Chen, Sheng-Che Chen, Chih-Han Chang
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Orthodontic tooth treatment has demonstrated a high success rate in clinical studies. It has been agreed upon that orthodontic tooth movement is based on the ability of surrounding bone and periodontal ligament (PDL) to react to a mechanical stimulus with remodeling processes. However, the mechanism of the tooth movement is still unclear. Recent studies focus on the simple principle compression-tension theory while rare studies directly measure tooth movement. Therefore, tracking tooth movement information during orthodontic treatment is very important in clinical practice. The aim of this study is to investigate the mechanism responses of the tooth movement during the orthodontic treatments. A stereovision system applied to track the tooth movement of the patient with the stamp brackets. The system was established by two cameras with their relative position calibrate. And the orthodontic force measured by 3D printing model with the six-axis load cell to determine the initial force application. The result shows that the stereovision system accuracy revealed the measurement presents a maximum error less than 2%. For the study on patient tracking, the incisor moved about 0.9 mm during 60 days tracking, and half of movement occurred in the first few hours. After removing the orthodontic force in 100 hours, the distance between before and after position incisor tooth decrease 0.5 mm consisted with the release of the phenomenon. Using the stereovision system can accurately locate the three-dimensional position of the teeth and superposition of 3D coordinate system for all the data to integrate the complex tooth movement.Keywords: orthodontic treatment, tooth movement, stereovision system, long-term tracking
Procedia PDF Downloads 4151202 The Association between Obstructive Sleep Apnea Syndrome and Driver Fatigue in North Taiwan Urban Areas
Authors: Cheng-Yu Tsai, Wen-Te Liu, Chen-Chen Lo, Yin-Tzu Lin, Kang Lo
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Background: Driving fatigue related to inadequate or disordered sleep accounts for a major percentage of traffic accidents. Obstructive sleep apnea syndrome (OSAS) is a common respiratory disorder during sleep. However, the effects of OSAS severity on driving drowsiness remain unclear. Objective: The aim of this study is to investigate the relationship between OSAS severity and driving fatigue. Methodologies: The physical condition while driving was obtained from the questionnaires to classify the state of driving fatigue. OSAS severity was quantified as the polysomnography, and the mean hourly number of greater than 3% dips in oxygen saturation during examination in a hospital in New Taipei City (Taiwan). The severity of OSAS was diagnosed by the apnea and hypopnea index (AHI) with the American Academy of Sleep Medicine (AASM) guideline. The logistic regression model was used to examine the associations after adjusted age, gender, neck circumstance, waist circumstance, and body mass index (BMI). Results: There were 880 subjects recruited in this study, who had been done polysomnography for evaluating severity for OSAS as well as completed the driver condition questionnaire. 752 subjects were diagnosed with OSA, and 484 subjects had fatigue driving behavior in the past week. Patients diagnosed with OSAS had a 9.42-fold higher odds ratio (p < 0.01, 95% CI = 5.41 – 16.42) of driving drowsiness for cohorts with a normal degree. Conclusion: We observe the considerable correlation between OSAS and driving fatigue. For the purpose of promoting traffic safety, OSAS should be monitored and treated.Keywords: obstructive sleep apnea syndrome, driving fatigue, polysomnography, apnea and hypopnea index
Procedia PDF Downloads 1241201 Spatial Rank-Based High-Dimensional Monitoring through Random Projection
Authors: Chen Zhang, Nan Chen
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High-dimensional process monitoring becomes increasingly important in many application domains, where usually the process distribution is unknown and much more complicated than the normal distribution, and the between-stream correlation can not be neglected. However, since the process dimension is generally much bigger than the reference sample size, most traditional nonparametric multivariate control charts fail in high-dimensional cases due to the curse of dimensionality. Furthermore, when the process goes out of control, the influenced variables are quite sparse compared with the whole dimension, which increases the detection difficulty. Targeting at these issues, this paper proposes a new nonparametric monitoring scheme for high-dimensional processes. This scheme first projects the high-dimensional process into several subprocesses using random projections for dimension reduction. Then, for every subprocess with the dimension much smaller than the reference sample size, a local nonparametric control chart is constructed based on the spatial rank test to detect changes in this subprocess. Finally, the results of all the local charts are fused together for decision. Furthermore, after an out-of-control (OC) alarm is triggered, a diagnostic framework is proposed. using the square-root LASSO. Numerical studies demonstrate that the chart has satisfactory detection power for sparse OC changes and robust performance for non-normally distributed data, The diagnostic framework is also effective to identify truly changed variables. Finally, a real-data example is presented to demonstrate the application of the proposed method.Keywords: random projection, high-dimensional process control, spatial rank, sequential change detection
Procedia PDF Downloads 2941200 Establishment of a Nomogram Prediction Model for Postpartum Hemorrhage during Vaginal Delivery
Authors: Yinglisong, Jingge Chen, Jingxuan Chen, Yan Wang, Hui Huang, Jing Zhnag, Qianqian Zhang, Zhenzhen Zhang, Ji Zhang
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Purpose: The study aims to establish a nomogram prediction model for postpartum hemorrhage (PPH) in vaginal delivery. Patients and Methods: Clinical data were retrospectively collected from vaginal delivery patients admitted to a hospital in Zhengzhou, China, from June 1, 2022 - October 31, 2022. Univariate and multivariate logistic regression were used to filter out independent risk factors. A nomogram model was established for PPH in vaginal delivery based on the risk factors coefficient. Bootstrapping was used for internal validation. To assess discrimination and calibration, receiver operator characteristics (ROC) and calibration curves were generated in the derivation and validation groups. Results: A total of 1340 cases of vaginal delivery were enrolled, with 81 (6.04%) having PPH. Logistic regression indicated that history of uterine surgery, induction of labor, duration of first labor, neonatal weight, WBC value (during the first stage of labor), and cervical lacerations were all independent risk factors of hemorrhage (P <0.05). The area-under-curve (AUC) of ROC curves of the derivation group and the validation group were 0.817 and 0.821, respectively, indicating good discrimination. Two calibration curves showed that nomogram prediction and practical results were highly consistent (P = 0.105, P = 0.113). Conclusion: The developed individualized risk prediction nomogram model can assist midwives in recognizing and diagnosing high-risk groups of PPH and initiating early warning to reduce PPH incidence.Keywords: vaginal delivery, postpartum hemorrhage, risk factor, nomogram
Procedia PDF Downloads 681199 Improvement of Ventilation and Thermal Comfort Using the Atrium Design for Traditional Folk Houses-Fujian Earthen Building
Authors: Ying-Ming Su
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Fujian earthen building which was known as a classic for ecological buildings was listed on the world heritage in 2008 (UNESCO) in China. Its design strategy can be applied to modern architecture planning and design. This study chose two different cases (Round Atrium: Er-Yi Building, Double Round Atrium: Zhen-Chen Building) of earthen building in Fu-Jian to compare the ventilation effects of different atrium forms. We adopt field measurements and computational fluid dynamics (CFD) simulation of temperature, humidity, and wind environment to identify the relationship between external environment and atrium about comfort and to confirm the relationship about atrium H/W (height/width). Results indicate that, through the atrium convection effect, it makes the natural wind guides to each space surrounded and keeps indoor comfort. It illustrates that the smaller the ratio of the H/W which is the relationship between the height and the width of an atrium is, the greater the wind speed generated within the street valley. Moreover, the wind speed is very close to the reference wind speed. This field measurement verifies that the value of H/W has great influence of solar radiation heat and sunshine shadows. The ventilation efficiency is: Er-Yi Building (H/W =0.2778) > Zhen-Chen Building (H/W=0.3670). Comparing the cases with the same shape but with different H/W, through the different size patios, airflow revolves in the atriums and can be brought into each interior space. The atrium settings meet the need of building ventilation, and can adjust the humidity and temperature within the buildings. It also creates good ventilation effect.Keywords: traditional folk houses, atrium, tulou, ventilation, building microclimate
Procedia PDF Downloads 4661198 Deep Reinforcement Learning for Optimal Decision-Making in Supply Chains
Authors: Nitin Singh, Meng Ling, Talha Ahmed, Tianxia Zhao, Reinier van de Pol
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We propose the use of reinforcement learning (RL) as a viable alternative for optimizing supply chain management, particularly in scenarios with stochasticity in product demands. RL’s adaptability to changing conditions and its demonstrated success in diverse fields of sequential decision-making makes it a promising candidate for addressing supply chain problems. We investigate the impact of demand fluctuations in a multi-product supply chain system and develop RL agents with learned generalizable policies. We provide experimentation details for training RL agents and statistical analysis of the results. We study the generalization ability of RL agents for different demand uncertainty scenarios and observe superior performance compared to the agents trained with fixed demand curves. The proposed methodology has the potential to lead to cost reduction and increased profit for companies dealing with frequent inventory movement between supply and demand nodes.Keywords: inventory management, reinforcement learning, supply chain optimization, uncertainty
Procedia PDF Downloads 1021197 Effects of GRF on CMJ in Different Wooden Surface Systems
Authors: Yi-cheng Chen, Ming-jum Guo, Yang-ru Chen
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Background and Objective: For safety and fair during basketball competition, FIBA proposes the definite level of physical functions in wooden surface system (WSS). There are existing various between different systems in indoor-stadium, so the aim of this study want to know how many effects in different WSS, especially for effects of ground reaction force(GRF) when player jumped. Materials and Methods: 12 participants acted counter-movement jump (CMJ) on 7 different surfaces, include 6 WSSs by 3 types rubber shock absorber pad (SAP) on cross or parallel fixed, and 1 rigid ground. GRFs of takeoff and landing had been recorded from an AMTI force platform when all participants acted vertical CMJs by counter-balance design. All data were analyzed using the one-way ANOVA to evaluate whether the test variable differed significantly between surfaces. The significance level was set at α=0.05. Results: There were non-significance in GRF between surfaces when participants taken off. For GRF of landing, we found WSS with cross fixed SAP are harder than parallel fixed. Although there were also non-significance when participant was landing on cross or parallel fixed surfaces, but there have test variable differed significantly between WSS with parallel fixed to rigid ground. In the study, landing to WSS with the hardest SAP, the GRF also have test variable differed significantly to other WSS. Conclusion: Although official basketball competition is in the WSS certificated by FIBA, there are also exist the various in GRF under takeoff or landing, any player must to warm-up before game starting. Especially, there is unsafe situation when play basketball on uncertificated WSS.Keywords: wooden surface system, counter-movement jump, ground reaction force, shock absorber pad
Procedia PDF Downloads 4371196 Rural-To-Urban Migrants' Experiences with Primary Care in Four Types of Medical Institutions in Guangzhou, China
Authors: Jiazhi Zeng, Leiyu Shi, Xia Zou, Wen Chen, Li Ling
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Background: China is facing the unprecedented challenge of rapidly increasing rural-to-urban migration. Due to the household registration system, migrants are in a vulnerable state when they attempt to access to primary care services. A strong primary care system can reduce health inequities and mitigate socioeconomic disparities in healthcare utilization. Literature indicated that migrants were more reliant on the primary care system than local residents. Although the Chinese government has attached great importance to creating an efficient health system, primary care services are still underutilized. The referral system between primary care institutions and hospitals has not yet been completely established in China. The general populations often go directly to hospitals instead of primary care institutions for their primary care. Primary care institutions generally consist of community health centers (CHCs) and community health stations (CHSs) in urban areas, and township health centers (THCs) and rural health stations (THSs) in rural areas. In addition, primary care services are also provided by the outpatient department of municipal hospitals and tertiary hospitals. A better understanding of migrants’ experiences with primary care in the above-mentioned medical institutions is critical for improving the performance of primary care institutions and providing indications of the attributes that require further attention. The purpose of this pioneering study is to explore rural-to-urban migrants’ experiences in primary care, compare their primary care experiences in four types of medical institutions in Guangzhou, China, and suggest implications for targeted interventions to improve primary care for the migrants. Methods: This was a cross-sectional study conducted with 736 rural-to-urban migrants in Guangzhou, China, in 2014. A multistage sampling method was employed. A validated Chinese version of Primary Care Assessment Tool - Adult Short Version (PCAT-AS) was used to collect information on migrants’ primary care experiences. The PCAT-AS consists of 10 domains. Analysis of covariance was conducted for comparison on PCAT domain scores and total scores among migrants accessing four types of medical institutions. Multiple linear regression models were used to explore factors associated with PCAT total scores. Results: After controlling for socio-demographic characteristics, migrant characteristics, health status and health insurance status, migrants accessing primary care in tertiary hospitals had the highest PCAT total scores when compared with those accessing primary care THCs/ RHSs (25.49 vs. 24.18, P=0.007) and CHCs/ CHSs(25.49 vs. 24.24, P=0.006). There was no statistical significant difference for PCAT total scores between migrants accessing primary care in CHCs/CHSs and those in municipal hospitals (24.24 vs. 25.02, P=0.436). Factors positively associated with higher PCAT total scores also included insurance covering parts of healthcare payment (P < 0.001). Conclusions: This study highlights the need for improvement in primary care provided by primary care institutions for rural-to-urban migrants. Migrants receiving primary care from THCs, RHSs, CHSs and CHSs reported worse primary care experiences than those receiving primary care from tertiary hospitals. Relevant policies related to medical insurance should be implemented for providing affordable healthcare services for migrants accessing primary care. Further research exploring the specific reasons for poorer PCAT scores of primary care institutions users will be needed.Keywords: China, PCAT, primary care, rural-to-urban migrants
Procedia PDF Downloads 3481195 The Effect of Austenitization Conditioning on the Mechanical Properties of Cr-Mo-V Hot Work Tool Steel with Different Nitrogen Addition
Authors: Iting Chiang, Cheng-Yu Wei, Chin-Teng Kuo, Po-Sheng Hsu, Yo-Lun Yang, Yung-Chang Kang, Chien-Chon Chen, Chih-Yuan Chen
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In recent years, it is reported that microalloying of nitrogen atoms within traditional Cr-Mo-V hot work tool steels can achieve better high temperature mechanical properties, which thus leads to such metallurgical approach widely utilized in the several commercial advanced hot work tool steels. Although the performance of hot work tool steel can be improved better by alloy composition design strategy, the influence of processing parameters on the mechanical property, especially on the service life of hot work tool steel, is still not fully understood yet. A longer service life of hot work tool steel can decrease the manufacturing cost effectively and thus become a research hot spot. According to several previous studies, it is generally acknowledged the service life of hot work tool steels can be increased effectively as the steels possessing higher hardness and toughness due to the formation and propagation of microcracks within the steel can be inhibited effectively. Therefore, in the present research, the designed experiments are primarily to explore the synergistic effect of nitrogen content and austenitization conditioning on the mechanical properties of hot work tool steels has been conducted and analyzed. No matter the nitrogen content, the results indicated the hardness of hot work tool steels increased as the austenitization treatment executed at higher temperature. On the other hand, an optimum toughness of hot work tool steel can be achieved as the austenitization treatment performed at a suitable temperature range. The possible explanation of such metallurgical phenomenon has been also proposed and analyzed in the present research.Keywords: hot work tool steel, Cr-Mo-V, toughness, hardness, TEM
Procedia PDF Downloads 551194 Application of Metaverse Service to Construct Nursing Education Theory and Platform in the Post-pandemic Era
Authors: Chen-Jung Chen, Yi-Chang Chen
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While traditional virtual reality and augmented reality only allow for small movement learning and cannot provide a truly immersive teaching experience to give it the illusion of movement, the new technology of both content creation and immersive interactive simulation of the metaverse can just reach infinite close to the natural teaching situation. However, the mixed reality virtual classroom of metaverse has not yet explored its theory, and it is rarely implemented in the situational simulation teaching of nursing education. Therefore, in the first year, the study will intend to use grounded theory and case study methods and in-depth interviews with nursing education and information experts. Analyze the interview data to investigate the uniqueness of metaverse development. The proposed analysis will lead to alternative theories and methods for the development of nursing education. In the second year, it will plan to integrate the metaverse virtual situation simulation technology into the alternate teaching strategy in the pediatric nursing technology course and explore the nursing students' use of this teaching method as the construction of personal technology and experience. By leveraging the unique features of distinct teaching platforms and developing processes to deliver alternative teaching strategies in a nursing technology teaching environment. The aim is to increase learning achievements without compromising teaching quality and teacher-student relationships in the post-pandemic era. A descriptive and convergent mixed methods design will be employed. Sixty third-grade nursing students will be recruited to participate in the research and complete the pre-test. The students in the experimental group (N=30) agreed to participate in 4 real-time mixed virtual situation simulation courses in self-practice after class and conducted qualitative interviews after each 2 virtual situation courses; the control group (N=30) adopted traditional practice methods of self-learning after class. Both groups of students took a post-test after the course. Data analysis will adopt descriptive statistics, paired t-tests, one-way analysis of variance, and qualitative content analysis. This study addresses key issues in the virtual reality environment for teaching and learning within the metaverse, providing valuable lessons and insights for enhancing the quality of education. The findings of this study are expected to contribute useful information for the future development of digital teaching and learning in nursing and other practice-based disciplines.Keywords: metaverse, post-pandemic era, online virtual classroom, immersive teaching
Procedia PDF Downloads 601193 Performance Investigation of Silica Gel Fluidized Bed
Authors: Sih-Li Chen, Chih-Hao Chen, Chi-Tong Chan
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Poor ventilation and high carbon dioxide (CO2) concentrations lead to the formation of sick buildings. This problem cannot simply be resolved by introducing fresh air from outdoor environments because this creates extra loads on indoor air-conditioning systems. Desiccants are widely used in air conditioning systems in tropical and subtropical regions with high humidity to reduce the latent heat load from fresh air. Desiccants are usually used as a packed-bed type, which is low cost, to combine with air-conditioning systems. Nevertheless, the pressure drop of a packed bed is too high, and the heat of adsorption caused by the adsorption process lets the temperature of the outlet air increase, bringing about an extra heat load, so the high pressure drop and the increased temperature of the outlet air are energy consumption sources needing to be resolved. For this reason, the gas-solid fluidised beds that have high heat and mass transfer rates, uniform properties and low pressure drops are very suitable for use in air-conditioning systems.This study experimentally investigates the performance of silica gel fluidized bed device which applying to an air conditioning system. In the experiments, commercial silica gel particles were filled in the two beds and to form a fixed packed bed and a fluidized bed. The results indicated that compared to the fixed packed bed device, the total adsorption and desorption by amounts of fluidized bed for 40 minutes increased 20.6% and 19.9% respectively when the bed height was 10 cm and superficial velocity was set to 2 m/s. In addition, under this condition, the pressure drop and outlet air temperature raise were reduced by 36.0% and 30.0%. Given the above results, application of the silica gel fluidized bed to air conditioning systems has great energy-saving potential.Keywords: fluidized bed, packed bed, silica gel, adsorption, desorption, pressure drop
Procedia PDF Downloads 5271192 Relationships of Driver Drowsiness and Sleep-Disordered Breathing Syndrome
Authors: Cheng-Yu Tsai, Wen-Te Liu, Yin-Tzu Lin, Chen-Chen Lo, Kang Lo
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Background: Driving drowsiness related to inadequate or disordered sleep accounts for a major percentage of traffic accidents. Sleep-disordered breathing (SDB) syndrome is a common respiratory disorder during sleep. However, the effects of SDB syndrome on driving fatigue remain unclear. Objective: This study aims to investigate the relationship between SDB pattern and driving drowsiness. Methodologies: The physical condition while driving was obtained from the questionnaires to classify the state of driving fatigue. SDB syndrome was quantified as the polysomnography, and the air flow pattern was collected by the thermistor and nasal pressure cannula. To evaluate the desaturation, the mean hourly number of greater than 3% dips in oxygen saturation was sentenced by reregistered technologist during examination in a hospital in New Taipei City (Taiwan). The independent T-test was used to investigate the correlations between sleep disorders related index and driving drowsiness. Results: There were 880 subjects recruited in this study, who had been done polysomnography for evaluating severity for obstructive sleep apnea syndrome (OSAS) as well as completed the driver condition questionnaire. Four-hundred-eighty-four subjects (55%) were classified as fatigue group, and 396 subjects (45%) were served as the control group. Significantly higher values of snoring index (242.14 ± 205.51 /hours) were observed in the fatigue group (p < 0.01). The value of respiratory disturbance index (RDI) (31.82 ± 19.34 /hours) in fatigue group were significantly higher than the control group (p < 0.01). Conclusion: We observe the considerable association between SDB syndrome and driving drowsiness. To promote traffic safety, SDB syndrome should be controlled and alleviated.Keywords: driving drowsiness, sleep-disordered breathing syndrome, snoring index, respiratory disturbance index.
Procedia PDF Downloads 1341191 A Simple Device for in-Situ Direct Shear and Sinkage Tests
Authors: A. Jerves, H. Ling, J. Gabaldon, M. Usoltceva, C. Couste, A. Agarwal, R. Hurley, J. Andrade
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This work introduces a simple device designed to perform in-situ direct shear and sinkage tests on granular materials as sand, clays, or regolith. It consists of a box nested within a larger box. Both have open bottoms, allowing them to be lowered into the material. Afterwards, two rotating plates on opposite sides of the outer box will rotate outwards in order to clear regolith on either side, providing room for the inner box to move relative to the plates and perform a shear test without the resistance of the surrounding soil. From this test, Coulomb parameters, including cohesion and internal friction angle, as well as, Bekker parameters can be inerred. This device has been designed for a laboratory setting, but with few modications, could be put on the underside of a rover for use in a remote location. The goal behind this work is to ultimately create a compact, but accurate measuring tool to put onto a rover or any kind of exploratory vehicle to test for regolith properties of celestial bodies.Keywords: simple shear, friction angle, Bekker parameters, device, regolith
Procedia PDF Downloads 5021190 Syntactic Errors in Written Assessments of Non-Native English-Speaking Undergraduate Students and Pedagogical Implications in Correcting Grammatical Mistakes
Authors: Cheng Shuk Ling
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This paper examines the English syntactic errors and their patterns in the written assignments of a General Education course at City University of Hong Kong. Subjects are 60 local and non-local (exchange) undergraduate students who are all EFL learners and L2 users with diversified education and disciplinary background (i.e. their major of study), which are unrelated to English language studies. The objective of this paper brings to the foreground a broad discussion of EFL/L2 undergraduate learners’ average syntactic ability in terms of written assessment. This paper is an attempt in classifying the patterns and categories of syntactic errors committed by students who were brought up and educated in non-native English-speaking countries. Thus, pedagogical recommendations are offered for both EFL/L2 learners and educators in tertiary education settings in such ways as to calibrate how and in what manner English language as the medium of instruction can lead to more enduring effects in learners within non-native English-speaking countries.Keywords: syntactic errors, english as a foreign language, second language users, pedagogy
Procedia PDF Downloads 761189 Finite Element Analysis of the Lumbar Spine after Unilateral and Bilateral Laminotomies and Laminectomy
Authors: Chih-Hsien Chen, Yi-Hung Ho, Chih-Wei Wang, Chih-Wei Chang, Yen-Nien Chen, Chih-Han Chang, Chun-Ting Li
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Laminotomy is a spinal decompression surgery compatible with a minimally invasive approach. However, the unilateral laminotomy for bilateral side decompression leads to more perioperative complications than the bilateral laminotomy. Although the unilateral laminotomy removes the least bone tissue among the spinal decompression surgeries, the difference of spinal stability between unilateral and bilateral laminotomy and laminectomy is rarely investigated. This study aims to compare the biomechanical effects of unilateral and bilateral laminotomy and laminectomy on the lumbar spine by finite element (FE) simulation. A three-dimensional FE model of the lumbar spine (L1–L5) was constructed with the vertebral body, discs, and ligaments, as well as the sacrum was constructed. Three different surgical methods, namely unilateral laminotomy, bilateral laminotomy and laminectomy, at L3–L4 and L4–L5 were considered. Partial pedicle and entire ligamentum flavum were removed to simulate bilateral decompression in laminotomy. The entire lamina and spinal processes from the lower L3 to upper L5 were detached in the laminectomy model. Then, four kinds of loadings, namely flexion, extension, lateral bending and rotation, were applied on the lumbar with various decompression conditions. The results indicated that the bilateral and unilateral laminotomy both increased the range of motion (ROM) compared with intact lumbar, while the laminectomy increased more ROM than both laminotomy did. The difference of ROM between the bilateral and unilateral laminotomy was very minor. Furthermore, bilateral laminotomy demonstrated similar poster element stress with unilateral laminotomy. Unilateral and bilateral laminotomy are equally suggested to bilateral decompression of lumbar spine with minimally invasive technique because limited effect was aroused due to more bone remove in the bilateral laminotomy on the lumbar stability. Furthermore, laminectomy is the last option for lumbar decompression.Keywords: minimally invasive technique, lumbar decompression, laminotomy, laminectomy, finite element method
Procedia PDF Downloads 1801188 Polypharmacy Overdose: Case Report on Mixed Overdose of Ramipril, Quetiapine, Lercanidipine and Duloxetine
Authors: Chui Ling Teng, R. Matsa
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We report a case with combined overdose of Lercanidipine (non-dihydropyridine calcium channel blocker), Quetiapine (Atypical antipsychotic), Ramipril and Duloxetine. A 66-year old male presented to the Emergency Department 12-hours after the ingestion of 1.2g Lercanidipine, 3g Quetiapine, 280mg of Ramipril and 420mg of Duloxetine. He describes lethargic, drowsiness and was unable to pass any urine since overdosed. He was found to be bradycardic, hypotensive and anuric. He had refractory hypotension and anuric despite fluid resuscitation, glucagon therapy and intravenous naloxone. His care was escalated to Intensive care, requiring noradrenaline, adrenaline, vasopressin, and hyperinsulinaemic euglycaemia therapy. He achieved haemodynamic stability and kidney function improved gradually with the support received. The total length of therapy lasted for 30 horus in which individual therapy was weaned down based on the requirement. He was then transferred to medical ward for further psychiatric assessment. This is a the first repored case of mixed overdose with lercanidipine, Quetiapine, Rampmipril and Duloxetine.Keywords: calcium channel blocker, hyperinsulinaemic Euglycaemia therapy, lercanidipine, overdose
Procedia PDF Downloads 3171187 Maximum Induced Subgraph of an Augmented Cube
Authors: Meng-Jou Chien, Jheng-Cheng Chen, Chang-Hsiung Tsai
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Let maxζG(m) denote the maximum number of edges in a subgraph of graph G induced by m nodes. The n-dimensional augmented cube, denoted as AQn, a variation of the hypercube, possesses some properties superior to those of the hypercube. We study the cases when G is the augmented cube AQn.Keywords: interconnection network, augmented cube, induced subgraph, bisection width
Procedia PDF Downloads 3981186 Nanoindentation Behaviour and Microstructural Evolution of Annealed Single-Crystal Silicon
Authors: Woei-Shyan Lee, Shuo-Ling Chang
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The nanoindentation behaviour and phase transformation of annealed single-crystal silicon wafers are examined. The silicon specimens are annealed at temperatures of 250, 350 and 450ºC, respectively, for 15 minutes and are then indented to maximum loads of 30, 50 and 70 mN. The phase changes induced in the indented specimens are observed using transmission electron microscopy (TEM) and micro-Raman scattering spectroscopy (RSS). For all annealing temperatures, an elbow feature is observed in the unloading curve following indentation to a maximum load of 30 mN. Under higher loads of 50 mN and 70 mN, respectively, the elbow feature is replaced by a pop-out event. The elbow feature reveals a complete amorphous phase transformation within the indented zone, whereas the pop-out event indicates the formation of Si XII and Si III phases. The experimental results show that the formation of these crystalline silicon phases increases with an increasing annealing temperature and indentation load. The hardness and Young’s modulus both decrease as the annealing temperature and indentation load are increased.Keywords: nanoindentation, silicon, phase transformation, amorphous, annealing
Procedia PDF Downloads 3601185 Optimal Placement and Sizing of Energy Storage System in Distribution Network with Photovoltaic Based Distributed Generation Using Improved Firefly Algorithms
Authors: Ling Ai Wong, Hussain Shareef, Azah Mohamed, Ahmad Asrul Ibrahim
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The installation of photovoltaic based distributed generation (PVDG) in active distribution system can lead to voltage fluctuation due to the intermittent and unpredictable PVDG output power. This paper presented a method in mitigating the voltage rise by optimally locating and sizing the battery energy storage system (BESS) in PVDG integrated distribution network. The improved firefly algorithm is used to perform optimal placement and sizing. Three objective functions are presented considering the voltage deviation and BESS off-time with state of charge as the constraint. The performance of the proposed method is compared with another optimization method such as the original firefly algorithm and gravitational search algorithm. Simulation results show that the proposed optimum BESS location and size improve the voltage stability.Keywords: BESS, firefly algorithm, PVDG, voltage fluctuation
Procedia PDF Downloads 3171184 Eight Weeks of Suspension Systems Training on Fat Mass, Jump and Physical Fitness Index in Female
Authors: Che Hsiu Chen, Su Yun Chen, Hon Wen Cheng
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Greater core stability may benefit sports performance by providing a foundation for greater force production in the upper and lower extremities. Core stability exercises on instability device (such as the TRX suspension systems) were found to be able to induce higher core muscle activity than performing on a stable surface. However, high intensity interval TRX suspension exercises training on sport performances remain unclear. The purpose of this study was to examine whether high intensity TRX suspension training could improve sport performance. Twenty-four healthy university female students (age 19.0 years, height 157.9 cm, body mass 51.3 kg, fat mass 25.2 %) were voluntarily participated in this study. After a familiarization session, each participant underwent five suspension exercises (e.g., hip abduction in plank alternative, hamstring curl, 45-degree row, lunge and oblique crunch). Each type of exercise was performed for 30 seconds, followed by 30 seconds break, two times per week for eight weeks while each exercise session was increased by 10 seconds every week. The results showed that the fat mass (about 12.92%) decreased significantly, sit and reach test (9%), 1 minute sit-up test (17.5%), standing broad jump (4.8%), physical fitness index (10.3%) increased significantly after 8-week high intensity TRX suspension training. Hence, eight weeks of high intensity interval TRX suspension exercises training can improve hamstring flexibility, trunk endurance, jump ability, aerobic fitness and fat mass percentage decreased substantially.Keywords: core endurance, jump, flexibility, cardiovascular fitness
Procedia PDF Downloads 4041183 Daily Dietary Intake and Cognitive Functioning among Population in Malaysia
Authors: Khor Khai Ling, Vashnarekha A/P Kumarasuriar, Tan Kok Wei, Ooi Pei Boon
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The food pyramid had been stressed for years and used to promote a healthy diet. Recently, the Ministry of Health in Malaysia has changed the food pyramid structure. They moved fruits and vegetables to the bottom layer and encouraged citizens to consume more fruits and vegetables. Past research has shown that the amount of vegetables and fruits consumption has associated with cognitive health. However, Malaysians have yet to achieve the amount of fruit and vegetable intake as per recommendation. Thus, this study aims to investigate Malaysian’s habitual diet and cognitive functioning via a cross-sectional study. One hundred and ninety-three participants will be recruited via convenient sampling. A Food Frequency Questionnaire (FFQ) measures the habitual diet, and an online cognitive test measures attention, executive functioning, and memory objectively. The collected one hundred samples to the date of abstract submission, and the data collection is still in progress. This study will provide an insight to Malaysian about the diet pattern and its relationship with cognitive performance.Keywords: attention, cognitive, executive functioning, habitual diet, memory
Procedia PDF Downloads 1951182 Using the Transtheoretical Model to Investigate Stages of Change in Regular Volunteer Service among Seniors in Community
Authors: Pei-Ti Hsu, I-Ju Chen, Jeu-Jung Chen, Cheng-Fen Chang, Shiu-Yan Yang
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Taiwan now is an aging society Research on the elderly should not be confined to caring for seniors, but should also be focused on ways to improve health and the quality of life. Senior citizens who participate in volunteer services could become less lonely, have new growth opportunities, and regain a sense of accomplishment. Thus, the question of how to get the elderly to participate in volunteer service is worth exploring. Apply the Transtheoretical Model to understand stages of change in regular volunteer service and voluntary service behaviour among the seniors. 1525 adults over the age of 65 from the Renai district of Keelung City were interviewed. The research tool was a self-constructed questionnaire and individual interviews were conducted to collect data. Then the data was processed and analyzed using the IBM SPSS Statistics 20 (Windows version) statistical software program. In the past six months, research subjects averaged 9.92 days of volunteer services. A majority of these elderly individuals had no intention to change their regular volunteer services. We discovered that during the maintenance stage, the self-efficacy for volunteer services was higher than during all other stages, but self-perceived barriers were less during the preparation stage and action stage. Self-perceived benefits were found to have an important predictive power for those with regular volunteer service behaviors in the previous stage, and self-efficacy was found to have an important predictive power for those with regular volunteer service behaviors in later stages. The research results support the conclusion that community nursing staff should group elders based on their regular volunteer services change stages and design appropriate behavioral change strategies.Keywords: seniors, stages of change in regular volunteer services, volunteer service behavior, self-efficacy, self-perceived benefits
Procedia PDF Downloads 4251181 The Empirical Analysis and Comparisons Using TAIEX Derivatives
Authors: Pao-Peng Hsu, Ying-Hsiu Chen
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Historical data shows that there were high correlations among TAIEX Futures, Electronic Sector Index Futures, Finance Sector Index Futures and Taiwan Top 50 ETF. The performance under various futures is also discussed. We found that the worst portfolio is consisted of T50-ETF and T50-ETF futures and best portfolio is consisted of T50-ETF and TF. It implies that the annual return of a portfolio increases if a portfolio’s risk diversifies.Keywords: arbitrage opportunities, ETF, futures, TAIEX
Procedia PDF Downloads 375