Search results for: Hong Yang
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1410

Search results for: Hong Yang

210 2106 kA/cm² Peak Tunneling Current Density in GaN-Based Resonant Tunneling Diode with an Intrinsic Oscillation Frequency of ~260GHz at Room Temperature

Authors: Fang Liu, JunShuai Xue, JiaJia Yao, GuanLin Wu, ZuMaoLi, XueYan Yang, HePeng Zhang, ZhiPeng Sun

Abstract:

Terahertz spectra is in great demand since last two decades for many photonic and electronic applications. III-Nitride resonant tunneling diode is one of the promising candidates for portable and compact THz sources. Room temperature microwave oscillator based on GaN/AlN resonant tunneling diode was reported in this work. The devices, grown by plasma-assisted molecular-beam epitaxy on free-standing c-plane GaN substrates, exhibit highly repeatable and robust negative differential resistance (NDR) characteristics at room temperature. To improve the interface quality at the active region in RTD, indium surfactant assisted growth is adopted to enhance the surface mobility of metal atoms on growing film front. Thanks to the lowered valley current associated with the suppression of threading dislocation scattering on low dislocation GaN substrate, a positive peak current density of record-high 2.1 MA/cm2 in conjunction with a peak-to-valley current ratio (PVCR) of 1.2 are obtained, which is the best results reported in nitride-based RTDs up to now considering the peak current density and PVCR values simultaneously. When biased within the NDR region, microwave oscillations are measured with a fundamental frequency of 0.31 GHz, yielding an output power of 5.37 µW. Impedance mismatch results in the limited output power and oscillation frequency described above. The actual measured intrinsic capacitance is only 30fF. Using a small-signal equivalent circuit model, the maximum intrinsic frequency of oscillation for these diodes is estimated to be ~260GHz. This work demonstrates a microwave oscillator based on resonant tunneling effect, which can meet the demands of terahertz spectral devices, more importantly providing guidance for the fabrication of the complex nitride terahertz and quantum effect devices.

Keywords: GaN resonant tunneling diode, peak current density, microwave oscillation, intrinsic capacitance

Procedia PDF Downloads 139
209 A Topology-Based Dynamic Repair Strategy for Enhancing Urban Road Network Resilience under Flooding

Authors: Xuhui Lin, Qiuchen Lu, Yi An, Tao Yang

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As global climate change intensifies, extreme weather events such as floods increasingly threaten urban infrastructure, making the vulnerability of urban road networks a pressing issue. Existing static repair strategies fail to adapt to the rapid changes in road network conditions during flood events, leading to inefficient resource allocation and suboptimal recovery. The main research gap lies in the lack of repair strategies that consider both the dynamic characteristics of networks and the progression of flood propagation. This paper proposes a topology-based dynamic repair strategy that adjusts repair priorities based on real-time changes in flood propagation and traffic demand. Specifically, a novel method is developed to assess and enhance the resilience of urban road networks during flood events. The method combines road network topological analysis, flood propagation modelling, and traffic flow simulation, introducing a local importance metric to dynamically evaluate the significance of road segments across different spatial and temporal scales. Using London's road network and rainfall data as a case study, the effectiveness of this dynamic strategy is compared to traditional and Transport for London (TFL) strategies. The most significant highlight of the research is that the dynamic strategy substantially reduced the number of stranded vehicles across different traffic demand periods, improving efficiency by up to 35.2%. The advantage of this method lies in its ability to adapt in real-time to changes in network conditions, enabling more precise resource allocation and more efficient repair processes. This dynamic strategy offers significant value to urban planners, traffic management departments, and emergency response teams, helping them better respond to extreme weather events like floods, enhance overall urban resilience, and reduce economic losses and social impacts.

Keywords: Urban resilience, road networks, flood response, dynamic repair strategy, topological analysis

Procedia PDF Downloads 35
208 A Combination of Mesenchymal Stem Cells and Low-Intensity Ultrasound for Knee Meniscus Regeneration: A Preliminary Study

Authors: Mohammad Nasb, Muhammad Rehan, Chen Hong

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Background Meniscus defects critically alter knee function and lead to degenerative changes. Regenerative medicine applications including stem cell transplantation have showed a promising efficacy in finding alternatives to overcome traditional treatment limitations. However, stem cell therapy remains limited due to the substantially reduced viability and inhibitory microenvironment. Since tissue growth and repair are under the control of biochemical and mechanical signals, several approaches have recently been investigated (e.g., low intensity pulsed ultrasound [LIPUS]) to promote the regeneration process. This study employed LIPUS to improve growth and osteogenic differentiation of mesenchymal stem cells derived from human embryonic stem cells to improve the regeneration of meniscus tissue. Methodology: The Mesenchymal stromal cells (MSCs) were transplanted into the epicenter of the injured meniscus in rabbits, which were randomized into two main groups: a treatment group (n=32 New Zealand rabbits) including 4 subgroups of 8 rabbits in each subgroup (LIPUS treatment, MSC treatment, LIPUS with MSC and control), and a second group (n=9) to track implanted cells and their progeny using green fluorescence protein (GFP). GFP consists of the MSC and LIPUS-MSC combination subgroups. Rabbits were then subjected to histological, immunohistochemistry, and MRI assessment. Results: The quantity of the newly regenerated tissue in the combination treatment group that had Ultrasound irradiation after mesenchymal stem cells were better at all end points. Likewise, Tissue quality scores were also greater in knees treated with both approaches compared with controls and single treatment at all end points, achieving significance at twelve and twenty-four weeks [p < 0.05], and [p = 0.008] at twelve weeks. Differentiation into type-I and II collagen-expressing cells were higher in the combination group at up to twenty-four weeks. Conclusions: the combination of mesenchymal stem cells and LIPUS showed greater adhering to the sites of meniscus injury, differentiate into cells resembling meniscal fibrochondrocytes, and improve both quality and quantity of meniscal regeneration.

Keywords: stem cells, regenerative medicine, osteoarthritis, knee

Procedia PDF Downloads 119
207 A Furniture Industry Concept for a Sustainable Generative Design Platform Employing Robot Based Additive Manufacturing

Authors: Andrew Fox, Tao Zhang, Yuanhong Zhao, Qingping Yang

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The furniture manufacturing industry has been slow in general to adopt the latest manufacturing technologies, historically relying heavily upon specialised conventional machinery. This approach not only requires high levels of specialist process knowledge, training, and capital investment but also suffers from significant subtractive manufacturing waste and high logistics costs due to the requirement for centralised manufacturing, with high levels of furniture product not re-cycled or re-used. This paper aims to address the problems by introducing suitable digital manufacturing technologies to create step changes in furniture manufacturing design, as the traditional design practices have been reported as building in 80% of environmental impact. In this paper, a 3D printing robot for furniture manufacturing is reported. The 3D printing robot mainly comprises a KUKA industrial robot, an Arduino microprocessor, and a self-assembled screw fed extruder. Compared to traditional 3D printer, the 3D printing robot has larger motion range and can be easily upgraded to enlarge the maximum size of the printed object. Generative design is also investigated in this paper, aiming to establish a combined design methodology that allows assessment of goals, constraints, materials, and manufacturing processes simultaneously. ‘Matrixing’ for part amalgamation and product performance optimisation is enabled. The generative design goals of integrated waste reduction increased manufacturing efficiency, optimised product performance, and reduced environmental impact institute a truly lean and innovative future design methodology. In addition, there is massive future potential to leverage Single Minute Exchange of Die (SMED) theory through generative design post-processing of geometry for robot manufacture, resulting in ‘mass customised’ furniture with virtually no setup requirements. These generatively designed products can be manufactured using the robot based additive manufacturing. Essentially, the 3D printing robot is already functional; some initial goals have been achieved and are also presented in this paper.

Keywords: additive manufacturing, generative design, robot, sustainability

Procedia PDF Downloads 131
206 Iron Supplementation for Patients Undergoing Cardiac Surgery: A Systematic Review and Meta-Analysis of Randomized-Controlled Trials

Authors: Matthew Cameron, Stephen Yang, Latifa Al Kharusi, Adam Gosselin, Anissa Chirico, Pouya Gholipour Baradari

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Background: Iron supplementation has been evaluated in several randomized controlled trials (RCTs) for the potential to increase baseline hemoglobin and decrease the incidence of red blood cell (RBC) transfusion during cardiac surgery. This study's main objective was to evaluate the evidence for iron administration in cardiac surgery patients for its effect on the incidence of perioperative RBC transfusion. Methods: This systematic review protocol was registered with PROSPERO (CRD42020161927) on Dec. 19th, 2019, and was prepared as per the PRISMA guidelines. MEDLINE, EMBASE, CENTRAL, Web of Science databases, and Google Scholar were searched for RCTs evaluating perioperative iron administration in adult patients undergoing cardiac surgery. Each abstract was independently reviewed by two reviewers using predefined eligibility criteria. The primary outcome was perioperative RBC transfusion, with secondary outcomes of the number of RBC units transfused, change in ferritin level, reticulocyte count, hemoglobin, and adverse events, after iron administration. The risk of bias was assessed with the Cochrane Collaboration Risk of Bias Tool, and the primary and secondary outcomes were analyzed with a random-effects model. Results: Out of 1556 citations reviewed, five studies (n = 554 patients) met the inclusion criteria. The use of iron demonstrated no difference in transfusion incidence (RR 0.86; 95% CI 0.65 to 1.13). There was a low heterogeneity between studies (I²=0%). The trial sequential analysis suggested an optimal information size of 1132 participants, which the accrued information size did not reach. Conclusion: The current literature does not support the routine use of iron supplementation before cardiac surgery; however, insufficient data is available to draw a definite conclusion. A critical knowledge gap has been identified, and more robust RCTs are required on this topic.

Keywords: cardiac surgery, iron, iron supplementation, perioperative medicine, meta-analysis, systematic review, randomized controlled trial

Procedia PDF Downloads 131
205 The On-Board Critical Message Transmission Design for Navigation Satellite Delay/Disruption Tolerant Network

Authors: Ji-yang Yu, Dan Huang, Guo-ping Feng, Xin Li, Lu-yuan Wang

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The navigation satellite network, especially the Beidou MEO Constellation, can relay data effectively with wide coverage and is applied in navigation, detection, and position widely. But the constellation has not been completed, and the amount of satellites on-board is not enough to cover the earth, which makes the data-relay disrupted or delayed in the transition process. The data-relay function needs to tolerant the delay or disruption in some extension, which make the Beidou MEO Constellation a delay/disruption-tolerant network (DTN). The traditional DTN designs mainly employ the relay table as the basic of data path schedule computing. But in practical application, especially in critical condition, such as the war-time or the infliction heavy losses on the constellation, parts of the nodes may become invalid, then the traditional DTN design could be useless. Furthermore, when transmitting the critical message in the navigation system, the maximum priority strategy is used, but the nodes still inquiry the relay table to design the path, which makes the delay more than minutes. Under this circumstances, it needs a function which could compute the optimum data path on-board in real-time according to the constellation states. The on-board critical message transmission design for navigation satellite delay/disruption-tolerant network (DTN) is proposed, according to the characteristics of navigation satellite network. With the real-time computation of parameters in the network link, the least-delay transition path is deduced to retransmit the critical message in urgent conditions. First, the DTN model for constellation is established based on the time-varying matrix (TVM) instead of the time-varying graph (TVG); then, the least transition delay data path is deduced with the parameters of the current node; at last, the critical message transits to the next best node. For the on-board real-time computing, the time delay and misjudges of constellation states in ground stations are eliminated, and the residual information channel for each node can be used flexibly. Compare with the minute’s delay of traditional DTN; the proposed transmits the critical message in seconds, which improves the re-transition efficiency. The hardware is implemented in FPGA based on the proposed model, and the tests prove the validity.

Keywords: critical message, DTN, navigation satellite, on-board, real-time

Procedia PDF Downloads 343
204 The Development of Documentary Filmmaking in Early Independent India

Authors: Camille Deprez

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This paper proposes to present research findings of an ongoing Hong Kong government-funded project on ‘The Documentary Film in India (1948-1975)’ (GRF 1240314), for which an extensive research fieldwork has been carried out in various archives in India. This project investigates the role and significance of the Indian documentary film sector from the inauguration of the state-sponsored Films Division one year after independence in 1948 until the declaration of a ‘State of Emergency’ in 1975. The documentary film production of this first period of national independence was characterised by increasing formal experimentation and analytical social and political enquiry, and by a complex, mixed structure of state-sponsored monopoly and free-market operation. However, that production remains significantly under-researched. What were the main production, distribution and exhibition strategies over this period? What were the recurrent themes and stylistic features of the films produced? In the new context of national independence (in which the State considered film as means of mass persuasion), consolidation of the commercial film, and the emergence of television and art cinema, what role did official, professional and creative factors play in the development of the documentary film sector? What were the impact of such films and the challenges faced by the documentary film in India? Based upon the crossed-analysis of primary written research documents, interviews and relevant films, this study interweaves empirical study of the sector's financing, production, distribution and exhibition strategies, as well as the films' content and form, with the larger historical context of India over the period from 1948 to 1975. Whilst most of the films made within the sector explored social issues, they were rarely able to do so from an overtly critical perspective. However, this paper proposes to analyse the contribution of important filmmakers and producers, including Ezra Mir, Paul Zils, Jean Bhownagary, S. Sukhdev, S. N. S. Sastri, and P. Pati, to the development of the Indian documentary film sector and style within and outside the remits of Films Division. It will more specifically assess the extent to which they criticised the State, showed the inequalities in Indian society and explored film form.

Keywords: documentary film, film archives, film history, India

Procedia PDF Downloads 297
203 The Enhancement of Target Localization Using Ship-Borne Electro-Optical Stabilized Platform

Authors: Jaehoon Ha, Byungmo Kang, Kilho Hong, Jungsoo Park

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Electro-optical (EO) stabilized platforms have been widely used for surveillance and reconnaissance on various types of vehicles, from surface ships to unmanned air vehicles (UAVs). EO stabilized platforms usually consist of an assembly of structure, bearings, and motors called gimbals in which a gyroscope is installed. EO elements such as a CCD camera and IR camera, are mounted to a gimbal, which has a range of motion in elevation and azimuth and can designate and track a target. In addition, a laser range finder (LRF) can be added to the gimbal in order to acquire the precise slant range from the platform to the target. Recently, a versatile functionality of target localization is needed in order to cooperate with the weapon systems that are mounted on the same platform. The target information, such as its location or velocity, needed to be more accurate. The accuracy of the target information depends on diverse component errors and alignment errors of each component. Specially, the type of moving platform can affect the accuracy of the target information. In the case of flying platforms, or UAVs, the target location error can be increased with altitude so it is important to measure altitude as precisely as possible. In the case of surface ships, target location error can be increased with obliqueness of the elevation angle of the gimbal since the altitude of the EO stabilized platform is supposed to be relatively low. The farther the slant ranges from the surface ship to the target, the more extreme the obliqueness of the elevation angle. This can hamper the precise acquisition of the target information. So far, there have been many studies on EO stabilized platforms of flying vehicles. However, few researchers have focused on ship-borne EO stabilized platforms of the surface ship. In this paper, we deal with a target localization method when an EO stabilized platform is located on the mast of a surface ship. Especially, we need to overcome the limitation caused by the obliqueness of the elevation angle of the gimbal. We introduce a well-known approach for target localization using Unscented Kalman Filter (UKF) and present the problem definition showing the above-mentioned limitation. Finally, we want to show the effectiveness of the approach that will be demonstrated through computer simulations.

Keywords: target localization, ship-borne electro-optical stabilized platform, unscented kalman filter

Procedia PDF Downloads 520
202 The Influence of Family of Origin on Children: A Comprehensive Model and Implications for Positive Psychology and Psychotherapy

Authors: Meichen He, Xuan Yang

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Background: In the field of psychotherapy, the role of the family of origin is of utmost importance. Over the past few decades, both individual-oriented and family-oriented approaches to child therapy have shown moderate success in reducing children's psychological and behavioral issues. Objective: However, in exploring how the family of origin influences individuals, it has been noted that there is a lack of comprehensive measurement indicators and an absence of an exact model to assess the impact of the family of origin on individual development. Therefore, this study aims to develop a model based on a literature review regarding the influence of the family of origin on children. Specifically, it will examine the effects of factors such as education level, economic status, maternal age, family integration, family violence, marital conflict, parental substance abuse, and alcohol consumption on children's self-confidence and life satisfaction. Through this research, we aim to further investigate the impact of the family of origin on children and provide directions for future research in positive psychology and psychotherapy. Methods: This study will employ a literature review methodology to gather and analyze relevant research articles on the influence of the family of origin on children. Subsequently, we will conduct quantitative analyses to establish a comprehensive model explaining how family of origin factors affect children's psychological and behavioral outcomes. Findings: the research has revealed that family of origin factors, including education level, economic status, maternal age, family integration, family violence, marital conflict, parental drug and alcohol consumption, have an impact on children's self-confidence and life satisfaction. These factors can affect children's psychological well-being and happiness through various pathways. Implications: The results of this study will contribute to a better understanding of the influence of the family of origin on children and provide valuable directions for future research in positive psychology and psychotherapy. This research will enhance awareness of children's psychological well-being and lay the foundation for improving psychotherapeutic methods.

Keywords: family of origion, positive psychology, developmental psychology, family education, social psychology, educational psychology

Procedia PDF Downloads 164
201 Rethinking Confucianism and Democracy

Authors: He Li

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Around the mid-1980s, Confucianism was reintroduced into China from Taiwan and Hong Kong as a result of China’s policies of reform and openness. Since then, the revival of neo-Confucianism in mainland China has accelerated and become a crucial component of the public intellectual sphere. The term xinrujia or xinruxue, loosely translated as “neo-Confucianism,” is increasingly understood as an intellectual and cultural phenomenon of the last four decades. The Confucian scholarship is in the process of restoration. This paper examines the Chinese intellectual discourse on Confucianism and democracy and places it in comparative and theoretical perspectives. With China’s rise and surge of populism in the West, particularly in the US, the leading political values of Confucianism could increasingly shape both China and the world at large. This state of affairs points to the need for more systematic efforts to assess the discourse on neo-Confucianism and its implications for China’s transformation. A number of scholars in the camp of neo-Confucianism maintain that some elements of Confucianism are not only compatible with democratic values and institutions but actually promote liberal democracy. They refer to it as Confucian democracy. By contrast, others either view Confucianism as a roadblock to democracy or envision that a convergence of democracy with Confucian values could result in a new hybrid system. The paper traces the complex interplay between Confucianism and democracy. It explores ideological differences between neo-Confucianism and liberal democracy and ascertains whether certain features of neo-Confucianism possess an affinity for the authoritarian political system. In addition to printed materials such as books and journal articles, a selection of articles from the website entitled Confucianism in China will be analyzed. The selection of this website is due to the fact that it is the leading website run by Chinese scholars focusing on neo-Confucianism. Another reason for selecting this website is its accessibility and availability. In the past few years, quite a few websites, left or right, were shut down by the authorities, but this website remains open. This paper explores the core components, dynamics, and implications of neo-Confucianism. My paper is divided into three parts. The first one discusses the origins of neo-Confucianism. The second section reviews the intellectual discourse among Chinese scholars on Confucian democracy. The third one explores the implications of the Chinese intellectual discourse on neo-Confucianism. Recently, liberal democracy has entered more conflict with official ideology. This paper, which is based on my extensive interviews in China prior to the pandemic and analysis of the primary sources in Chinese, will lay the foundation for a chapter on neo-Confucianism and democracy in my next book-length manuscript, tentatively entitled Chinese Intellectual Discourse on Democracy.

Keywords: China, confucius, confucianism, neo-confucianism, democracy

Procedia PDF Downloads 81
200 Impact of Relaxing Incisions on Maxillofacial Growth Following Sommerlad–Furlow Modified Technique in Patients with Isolated Cleft Palate: A Preliminary Comparative Study

Authors: Sadam Elayah, Yang Li, Bing Shi

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Background: The impact of relaxing incisions on maxillofacial growth during palatoplasty remains a topic of debate, and further research is needed to understand its effects fully. Thus, the current study is the first long-term study that aimed to assess the maxillofacial growth of patients with isolated cleft palate following the Sommerlad-Furlow modified (S.F) technique and to estimate the impact of relaxing incisions on maxillofacial growth following S.F technique in patients with isolated cleft palate. Methods: A total of 85 participants, 55 patients with non-syndromic isolated soft and hard cleft palate underwent primary palatoplasty with our technique (30 patients received the Sommerlad-Furlow modified technique without relaxing incision (S.F+RI group), and 25 received Sommerlad-Furlow modified technique without relaxing (S.F-RI group) with no significant difference found between them regarding the cleft type, cleft width, and age at repair. While the other 30 were normal participants with skeletal class I pattern (C group). The control group was matched with the study group in number, age, and sex. All the study variables were measured using stable landmarks, including 12 linear and 10 angular variants. Results: The mean ages at collection of cephalograms were 6.03±0.80 in the S.F+RI group, 5.96±0.76 in the S.F-RI group, and 5.91±0.87 in the C group. Regarding cranial base, the results showed no statistically significant differences between the three groups in S-N and S-N-Ba. The S.F+R.I group had a significantly shorter S-Ba than the S.F-R.I & C groups (P= 0.01). However, there was no statistically significant difference between the S.F-R.I & C groups (P=0.80). Regarding the skeletal maxilla, there was no significant difference between the S.F+R.I and S.F-R.I groups in all linear measurements (N-ANS, S- PM & SN-PP ) except Co-A, the S.F+R.I group had significantly shorter Co-A than the S.F-R.I & C groups (P= <0.01). While the angular measurement, S.F+R.I group had significantly less SNA angle than the S.F-R.I & C groups (P= <0.01). Regarding mandibular bone, there were no statistically significant differences in all linear and angular mandibular measurements between the S.F+R.I and S.F-R.I groups. Regarding intermaxillary relation, the S.F+R.I group had significant differences in Co-Gn - Co-A and ANB compared to the S.F-R.I & C groups (P= <0.01). There was no statistically significant difference in PP-MP among the three groups. Conclusion: As a preliminary report, the Sommerlad-Furlow modified technique without relaxing incisions was found to have good maxillary positioning in the face and a satisfactory intermaxillary relationship compared to the Sommerlad-Furlow modified technique with relaxing incisions.

Keywords: relaxing incisions, cleft palate, palatoplasty, maxillofacial growth

Procedia PDF Downloads 111
199 Knowledge Loss Risk Assessment for Departing Employees: An Exploratory Study

Authors: Muhammad Saleem Ullah Khan Sumbal, Eric Tsui, Ricky Cheong, Eric See To

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Organizations are posed to a threat of valuable knowledge loss when employees leave either due to retirement, resignation, job change or because of disabilities e.g. death, etc. Due to changing economic conditions, globalization, and aging workforce, organizations are facing challenges regarding retention of valuable knowledge. On the one hand, large number of employees are going to retire in the organizations whereas on the other hand, younger generation does not want to work in a company for a long time and there is an increasing trend of frequent job change among the new generation. Because of these factors, organizations need to make sure that they capture the knowledge of employee before (s)he walks out of the door. The first step in this process is to know what type of knowledge employee possesses and whether this knowledge is important for the organization. Researchers reveal in the literature that despite the serious consequences of knowledge loss in terms of organizational productivity and competitive advantage, there has not been much work done in the area of knowledge loss assessment of departing employees. An important step in the knowledge retention process is to determine the critical ‘at risk’ knowledge. Thus, knowledge loss risk assessment is a process by which organizations can gauge the importance of knowledge of the departing employee. The purpose of this study is to explore this topic of knowledge loss risk assessment by conducting a qualitative study in oil and gas sector. By engaging in dialogues with managers and executives of the organizations through in-depth interviews and adopting a grounded methodology approach, the research will explore; i) Are there any measures adopted by organizations to assess the risk of knowledge loss from departing employees? ii) Which factors are crucial for knowledge loss assessment in the organizations? iii) How can we prioritize the employees for knowledge retention according to their criticality? Grounded theory approach is used when there is not much knowledge available in the area under research and thus new knowledge is generated about the topic through an in-depth exploration of the topic by using methods such as interviews and using a systematic approach to analyze the data. The outcome of the study will generate a model for the risk of knowledge loss through factors such as the likelihood of knowledge loss, the consequence/impact of knowledge loss and quality of the knowledge loss of departing employees. Initial results show that knowledge loss assessment is quite crucial for the organizations and it helps in determining what types of knowledge employees possess e.g. organizations knowledge, subject matter expertise or relationships knowledge. Based on that, it can be assessed which employee is more important for the organizations and how to prioritize the knowledge retention process for departing employees.

Keywords: knowledge loss, risk assessment, departing employees, Hong Kong organizations

Procedia PDF Downloads 408
198 Study on the Voltage Induced Wrinkling of Elastomer with Different Electrode Areas

Authors: Zhende Hou, Fan Yang, Guoli Zhang

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Dielectric elastomer is a promising class of Electroactive polymers which can deform in response to an applied electric field. Comparing general smart material, the Dielectric elastomer is more compliance and can achieve higher energy density, which can be for diverse applications such as actuators, artificial muscles, soft robotics, and energy harvesters. The coupling of the Electroactive polymers and the electric field is that the elastomer is sandwiched between two compliant electrodes and when the electrodes are subjected to a voltage, the positive and negative charges on the two electrodes compress the polymer, so that the polymer reduces in thickness and expands in area. However, the pre-stretched dielectric elastomer film not only can achieve large electric-field induced deformation but also is prone to wrinkling, under the interaction of its own strain energy and the applied electric field energy. For a uniaxially pre-stretched dielectric elastomer film, the electrode area is an important parameter to the electric-field induced deformation and may also be a key factor affecting the film wrinkling. To determine and quantify the effect experimentally, VHB 9473 tapes were employed and compliant electrodes with different areas were pant on each of them. The tape was first tensed to a uniaxial stretch of 8. Then a DC voltage was applied to the electrodes and increased gradually until wrinkling occurred in the film. Then, the critical wrinkling voltages of the film with different electrode areas were obtained, and the wrinkle wavelengths were obtained simultaneously for analyzing the wrinkling characteristics. Experimental results indicate when the electrode area is smaller the wrinkling voltage is higher, and with the increases of electrode area, the wrinkling voltage decreases rapidly until a specific area. Beyond that, the wrinkling voltage becomes larger gradually with the increases of the area. While the wrinkle wavelength decreases gradually with the increase of voltage monotonically. That is, the relation between the critical wrinkling voltage and the electrode areas is U-shaped. Analysis believes that the film wrinkling is a kind of local effect, the interaction and the energy transfer between electrode region and non-electrode region have great influence on wrinkling. In the experiment, very thin copper wires are used as the electrode leads that just contact with the electrodes, which can avoid the stiffness of the leads affecting the wrinkling.

Keywords: elastomers, uniaxial stretch, electrode area, wrinkling

Procedia PDF Downloads 248
197 Anticoccidial Effects of the Herbal Mixture in Boilers after Eimeria spp. Infection

Authors: Yang-Ho Jang, Soon-Ok Jee, Hae-Chul Park, Jeong-Woo Kang, Byung-Jae So, Sung-Shik Shin, Kyu-Sung Ahn, Kwang-Jick Lee

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Introduction: Antibiotics have been used as feed additives for the growth promotion and performance in food-producing animals. However, the possibility of selection of antimicrobial resistance and the concerns of residue in animal products led to ban the use of antibiotics in farm animals at 2011 in Korea. This strategy is also adjusted to anticoccidial drugs soon but these are still allowed for the time being to use in a diet for the treatment and control for the enteric necrosis in poultry. Therefore substantial focus has been given to find alternatives to antimicrobial agents. Several phytogenic materials have been reported to have positive effects on coccidiosis. This study was to evaluate the effects on anti-coccidial effect of oregano oil based herb mixture on Eimeria spp. in poultry. Materials and Methods: A total of one day-old boiler chickens divided into six groups (each group=30 chkckens) were used in this study. The herbal mixture was fed with water freely as follows: two groups, one infected with Eimeria spp. and the other group served as controls without herbal mixture respectively; 0.2ml/L of oregano oil; 0.2ml/L of oregano oil and Sanguisorbae radix; 0.2ml/L of Sanguisorbae radix; last group was fed with dichlazuril diet as positive control. Sporulated Eimeria spp. was infected at 14 day-old. Following infection, survival rate, bloody diarrhea, OPG (oocyst per gram) and feed conversion ratios were determined. The experimental period was lasted for 4 weeks. Results: Herbal mixture feeding groups (Group 3,4,5) showed low feed conversion ratio comparing with negative control. Oregano oil group and positive control group recorded the highest survival rate. The grade of bloody diarrhea was scored 0 to 5. Herbal mixture feeding groups showed 2, 3 and 1 score respectively however, group 2 (infection and no-treatment) showed 4. OPG results in herbal mixture feeding group were 3 to 4 times higher than diclazuril diet feeding group. Conclusions: These results showed that oregano oil and Sanguisorbae radix mixture may have an anti-coccidial effect and also affect chick performance.

Keywords: anticoccidial effects, oregano oil based herb mixture, herbal mixture, antibiotics

Procedia PDF Downloads 554
196 Development of a Sprayable Piezoelectric Material for E-Textile Applications

Authors: K. Yang, Y. Wei, M. Zhang, S. Yong, R. Torah, J. Tudor, S. Beeby

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E-textiles are traditional textiles with integrated electronic functionality. It is an emerging innovation with numerous applications in fashion, wearable computing, health and safety monitoring, and the military and medical sectors. The piezoelectric effect is a widespread and versatile transduction mechanism used in sensor and actuator applications. Piezoelectric materials produce electric charge when stressed. Conversely, mechanical deformation occurs when an electric field is applied across the material. Lead Zirconate Titanate (PZT) is a widely used piezoceramic material which has been used to fabricate e-textiles through screen printing, electro spinning and hydrothermal synthesis. This paper explores an alternative fabrication process: Spray coating. Spray coating is a straightforward and cost effective fabrication method applicable on both flat and curved surfaces. It can also be applied selectively by spraying through a stencil which enables the required design to be realised on the substrate. This work developed a sprayable PZT based piezoelectric ink consisting of a binder (Fabink-Binder-01), PZT powder (80 % 2 µm and 20 % 0.8 µm) and acetone as a thinner. The optimised weight ratio of PZT/binder is 10:1. The components were mixed using a SpeedMixer DAC 150. The fabrication processes is as follows: 1) Screen print a UV-curable polyurethane interface layer on the textile to create a smooth textile surface. 2) Spray one layer of a conductive silver polymer ink through a pre-designed stencil and dry at 90 °C for 10 minutes to form the bottom electrode. 3) Spray three layers of the PZT ink through a pre-designed stencil and dry at 90 °C for 10 minutes for each layer to form a total thickness of ~250µm PZT layer. 4) Spray one layer of the silver ink through a pre-designed stencil on top of the PZT layer and dry at 90 °C for 10 minutes to form the top electrode. The domains of the PZT elements were aligned by polarising the material at an elevated temperature under a strong electric field. A d33 of 37 pC/N has been achieved after polarising at 90 °C for 6 minutes with an electric field of 3 MV/m. The application of the piezoelectric textile was demonstrated by fabricating a pressure sensor to switch an LED on/off. Other potential applications on e-textiles include motion sensing, energy harvesting, force sensing and a buzzer.

Keywords: piezoelectric, PZT, spray coating, pressure sensor, e-textile

Procedia PDF Downloads 465
195 Effect of Mindfulness Training on Psychological Well-Being: An Experimental Study Using a Mobile App as Intervention

Authors: Beeto W. C. Leung, Nicole C. Y. Lee

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It was well known that college students experienced a high level of stress and anxiety. College athletes, a special group of college students, may even encounter a higher level of pressure and distress due to their dual endeavors in academic and athletic settings. Due to the high demands and costs of mental health services, easily accessible, web-based self-help interventions are getting more popular. The aim of the present experimental study was to examine the potential intervention effect of a mindfulness-based self-help mobile App, called 'Smiling Mind', on mindfulness and psychological well-being. Forty-six college athletes, recruited from athletic teams of two local universities in Hong Kong, were randomly assigned to the Mindfulness App Group (MAG) and the Control Group (CG). All participants were administered the Mindful Attention Awareness Scale, Geriatric Depression Scale, and Perceived Stress Scale-10 before the study (Time 1, T1) and after the 4-week intervention (Time 2, T2). MAG was requested to use the app and follow the instructions every day for at least 5 days per week. Participants were also asked to record their daily app usage time. Results showed that, for MAG, from T1 to T2, mindfulness has been increased from 3.25 to 3.92; depressive symptoms and stress has been significantly decreased from 8.6 to 5.1 and 24.8 to 13.5 respectively while for the CG, mindfulness has been decreased slightly from 3.29 to 3.13; depressive symptoms and stress has been slightly increased from 7.1 to 7.3 and 24.1 to 27.1 respectively. Three mixed-design ANOVAs with time (T1, T2) as the within-subjects factor and intervention group (MAG, CG) as the between-subjects factor revealed a main effect of time on mindfulness, F(1, 41) = 10.28, p < 0.01, depressive symptoms, F(1, 41) = 6.55, p < 0.02 and stress, F(1, 41) = 16.96, p < 0.001 respectively. Both predicted interaction between time and intervention group on mindfulness, F(1, 41) = 26.6, p < 0.001, ηp 2 =0.39, depressive symptoms, F(1, 41) = 8.00, p < 0.01, ηp 2 =0.16 and Stress F(1, 41) = 49.3, p < 0.001, ηp 2 =0.55 were significant meaning that participants using the Mindfulness Mobile App in the intervention did experienced a significant increase in mindfulness and significant decrease in depressive symptoms and perceived level of stress after the 4-week intervention when compared with the control group. The present study provided encouraging empirical support for using Smiling Mind, a self-help mobile app, to promote mindfulness and mental health in a cost-effective way. Further studies should examine the potential use of Smiling Mind in different samples, including children and adolescence, as well as, investigate the lasting effects of using the app on other psychosocial outcomes such as emotional regulations.

Keywords: college athletes, experimental study, mindfulness mobile apps, psychological well-being

Procedia PDF Downloads 117
194 Advancing Healthcare Excellence in China: Crafting a Strategic Operational Evaluation Index System for Chinese Hospital Departments amid Payment Reform Initiatives

Authors: Jing Jiang, Yuguang Gao, Yang Yu

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Facing increasingly challenging insurance payment pressures, the Chinese healthcare system is undergoing significant transformations, akin to the implementation of DRG payment models by the United States' Medicare. Consequently, there is a pressing need for Chinese hospitals to establish optimizations in departmental operations tailored to the ongoing healthcare payment reforms. This abstract delineates the meticulous construction of a scientifically rigorous and comprehensive index system at the departmental level in China strategically aligned with the evolving landscape of healthcare payment reforms. Methodologically, it integrates key process areas and maturity assessment theories, synthesizing relevant literature and industry standards to construct a robust framework and indicator pool. Employing the Delphi method, consultations with 21 experts were conducted, revealing a collective demonstration of high enthusiasm, authority, and coordination in designing the index system. The resulting model comprises four primary indicators -technical capabilities, cost-effectiveness, operational efficiency, and disciplinary potential- supported by 14 secondary indicators and 23 tertiary indicators with varied coefficient adjustment for department types (platform or surgical). The application of this evaluation system in a Chinese hospital within the northeastern region yielded results aligning seamlessly with the actual operational scenario. In conclusion, the index system comprehensively considers the integrity and effectiveness of structural, process, and outcome indicators and stands as a comprehensive reflection of the collective expertise of the engaged experts, manifesting in a model designed to elevate the operational management of hospital departments. Its strategic alignment with healthcare payment reforms holds practical significance in guiding departmental development positioning, brand cultivation, and talent development.

Keywords: Chinese healthcare system, Delphi method, departmental management, evaluation indicators, hospital operations, weight coefficients

Procedia PDF Downloads 66
193 Effects of Subsidy Reform on Consumption and Income Inequalities in Iran

Authors: Pouneh Soleimaninejadian, Chengyu Yang

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In this paper, we use data on Household Income and Expenditure survey of Statistics Centre of Iran, conducted from 2005-2014, to calculate several inequality measures and to estimate the effects of Iran’s targeted subsidy reform act on consumption and income inequality. We first calculate Gini coefficients for income and consumption in order to study the relation between the two and also the effects of subsidy reform. Results show that consumption inequality has not been always mirroring changes in income inequality. However, both Gini coefficients indicate that subsidy reform caused improvement in inequality. Then we calculate Generalized Entropy Index based on consumption and income for years before and after the Subsidy Reform Act of 2010 in order to have a closer look into the changes in internal structure of inequality after subsidy reforms. We find that the improvement in income inequality is mostly caused by the decrease in inequality of lower income individuals. At the same time consumption inequality has been decreased as a result of more equal consumption in both lower and higher income groups. Moreover, the increase in Engle coefficient after the subsidy reform shows that a bigger portion of income is allocated to consumption on food which is a sign of lower living standard in general. This increase in Engle coefficient is due to rise in inflation rate and relative increase in price of food which partially is another consequence of subsidy reform. We have conducted some experiments on effect of subsidy payments and possible effects of change on distribution pattern and amount of cash subsidy payments on income inequality. Result of the effect of cash payments on income inequality shows that it leads to a definite decrease in income inequality and had a bigger share in improvement of rural areas compared to those of urban households. We also examine the possible effect of constant payments on the increasing income inequality for years after 2011. We conclude that reduction in value of payments as a result of inflation plays an important role regardless of the fact that there may be other reasons. We finally experiment with alternative allocations of transfers while keeping the total amount of cash transfers constant or make it smaller through eliminating three higher deciles from the cash payment program, the result shows that income equality would be improved significantly.

Keywords: consumption inequality, generalized entropy index, income inequality, Irans subsidy reform

Procedia PDF Downloads 235
192 Genetic Improvement Potential for Wood Production in Melaleuca cajuputi

Authors: Hong Nguyen Thi Hai, Ryota Konda, Dat Kieu Tuan, Cao Tran Thanh, Khang Phung Van, Hau Tran Tin, Harry Wu

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Melaleuca cajuputi is a moderately fast-growing species and considered as a multi-purpose tree as it provides fuelwood, piles and frame poles in construction, leaf essential oil and honey. It occurs in Australia, Papua New Guinea, and South-East Asia. M. cajuputi plantation can be harvested on 6-7 year rotations for wood products. Its timber can also be used for pulp and paper, fiber and particle board, producing quality charcoal and potentially sawn timber. However, most reported M. cajuputi breeding programs have been focused on oil production rather than wood production. In this study, breeding program of M. cajuputi aimed to improve wood production was examined by estimating genetic parameters for growth (tree height, diameter at breast height (DBH), and volume), stem form, stiffness (modulus of elasticity (MOE)), bark thickness and bark ratio in a half-sib family progeny trial including 80 families in the Mekong Delta of Vietnam. MOE is one of the key wood properties of interest to the wood industry. Non-destructive wood stiffness was measured indirectly by acoustic velocity using FAKOPP Microsecond Timer and especially unaffected by bark mass. Narrow-sense heritability for the seven traits ranged from 0.13 to 0.27 at age 7 years. MOE and stem form had positive genetic correlations with growth while the negative correlation between bark ratio and growth was also favorable. Breeding for simultaneous improvement of multiple traits, faster growth with higher MOE and reduction of bark ratio should be possible in M. cajuputi. Index selection based on volume and MOE showed genetic gains of 31 % in volume, 6 % in MOE and 13 % in stem form. In addition, heritability and age-age genetic correlations for growth traits increased with time and optimal early selection age for growth of M. cajuputi based on DBH alone was 4 years. Selected thinning resulted in an increase of heritability due to considerable reduction of phenotypic variation but little effect on genetic variation.

Keywords: acoustic velocity, age-age correlation, bark thickness, heritability, Melaleuca cajuputi, stiffness, thinning effect

Procedia PDF Downloads 182
191 Exo-III Assisted Amplification Strategy through Target Recycling of Hg²⁺ Detection in Water: A GNP Based Label-Free Colorimetry Employing T-Rich Hairpin-Loop Metallobase

Authors: Abdul Ghaffar Memon, Xiao Hong Zhou, Yunpeng Xing, Ruoyu Wang, Miao He

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Due to deleterious environmental and health effects of the Hg²⁺ ions, various online, detection methods apart from the traditional analytical tools have been developed by researchers. Biosensors especially, label, label-free, colorimetric and optical sensors have advanced with sensitive detection. However, there remains a gap of ultrasensitive quantification as noise interact significantly especially in the AuNP based label-free colorimetry. This study reported an amplification strategy using Exo-III enzyme for target recycling of Hg²⁺ ions in a T-rich hairpin loop metallobase label-free colorimetric nanosensor with an improved sensitivity using unmodified gold nanoparticles (uGNPs) as an indicator. The two T-rich metallobase hairpin loop structures as 5’- CTT TCA TAC ATA GAA AAT GTA TGT TTG -3 (HgS1), and 5’- GGC TTT GAG CGC TAA GAA A TA GCG CTC TTT G -3’ (HgS2) were tested in the study. The thermodynamic properties of HgS1 and HgS2 were calculated using online tools (http://biophysics.idtdna.com/cgi-bin/meltCalculator.cgi). The lab scale synthesized uGNPs were utilized in the analysis. The DNA sequence had T-rich bases on both tails end, which in the presence of Hg²⁺ forms a T-Hg²⁺-T mismatch, promoting the formation of dsDNA. Later, the Exo-III incubation enable the enzyme to cleave stepwise mononucleotides from the 3’ end until the structure become single-stranded. These ssDNA fragments then adsorb on the surface of AuNPs in their presence and protect AuNPs from the induced salt aggregation. The visible change in color from blue (aggregation stage in the absence of Hg²⁺) and pink (dispersion state in the presence of Hg²⁺ and adsorption of ssDNA fragments) can be observed and analyzed through UV spectrometry. An ultrasensitive quantitative nanosensor employing Exo-III assisted target recycling of mercury ions through label-free colorimetry with nanomolar detection using uGNPs have been achieved and is further under the optimization to achieve picomolar range by avoiding the influence of the environmental matrix. The proposed strategy will supplement in the direction of uGNP based ultrasensitive, rapid, onsite, label-free colorimetric detection.

Keywords: colorimetric, Exo-III, gold nanoparticles, Hg²⁺ detection, label-free, signal amplification

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190 Liver Regeneration of Small in situ Injury

Authors: Ziwei Song, Junjun Fan, Jeremy Teo, Yang Yu, Yukun Ma, Jie Yan, Shupei Mo, Lisa Tucker-Kellogg, Peter So, Hanry Yu

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Liver is the center of detoxification and exposed to toxic metabolites all the time. It is highly regenerative after injury, with the ability to restore even after 70% partial hepatectomy. Most of the previous studies were using hepatectomy as injury models for liver regeneration study. There is limited understanding of small-scale liver injury, which can be caused by either low dose drug consumption or hepatocyte routine metabolism. Although these small in situ injuries do not cause immediate symptoms, repeated injuries will lead to aberrant wound healing in liver. Therefore, the cellular dynamics during liver regeneration is critical for our understanding of liver regeneration mechanism. We aim to study the liver regeneration of small-scale in situ liver injury in transgenic mice labeling actin (Lifeact-GFP). Previous studies have been using sample sections and biopsies of liver, which lack real-time information. In order to trace every individual hepatocyte during the regeneration process, we have developed and optimized an intravital imaging system that allows in vivo imaging of mouse liver for consecutive 5 days, allowing real-time cellular tracking and quantification of hepatocytes. We used femtosecond-laser ablation to make controlled and repeatable liver injury model, which mimics the real-life small in situ liver injury. This injury model is the first case of its kind for in vivo study on liver. We found that small-scale in situ liver injury is repaired by the coordination of hypertrophy and migration of hepatocytes. Hypertrophy is only transient at initial phase, while migration is the main driving force to complete the regeneration process. From cellular aspect, Akt/mTOR pathway is activated immediately after injury, which leads to transient hepatocyte hypertrophy. From mechano-sensing aspect, the actin cable, formed at apical surface of wound proximal hepatocytes, provides mechanical tension for hepatocyte migration. This study provides important information on both chemical and mechanical signals that promote liver regeneration of small in situ injury. We conclude that hypertrophy and migration play a dominant role at different stages of liver regeneration.

Keywords: hepatocyte, hypertrophy, intravital imaging, liver regeneration, migration

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189 Detecting Impact of Allowance Trading Behaviors on Distribution of NOx Emission Reductions under the Clean Air Interstate Rule

Authors: Yuanxiaoyue Yang

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Emissions trading, or ‘cap-and-trade', has been long promoted by economists as a more cost-effective pollution control approach than traditional performance standard approaches. While there is a large body of empirical evidence for the overall effectiveness of emissions trading, relatively little attention has been paid to other unintended consequences brought by emissions trading. One important consequence is that cap-and-trade could introduce the risk of creating high-level emission concentrations in areas where emitting facilities purchase a large number of emission allowances, which may cause an unequal distribution of environmental benefits. This study will contribute to the current environmental policy literature by linking trading activity with environmental injustice concerns and empirically analyzing the causal relationship between trading activity and emissions reduction under a cap-and-trade program for the first time. To investigate the potential environmental injustice concern in cap-and-trade, this paper uses a differences-in-differences (DID) with instrumental variable method to identify the causal effect of allowance trading behaviors on emission reduction levels under the clean air interstate rule (CAIR), a cap-and-trade program targeting on the power sector in the eastern US. The major data source is the facility-year level emissions and allowance transaction data collected from US EPA air market databases. While polluting facilities from CAIR are the treatment group under our DID identification, we use non-CAIR facilities from the Acid Rain Program - another NOx control program without a trading scheme – as the control group. To isolate the causal effects of trading behaviors on emissions reduction, we also use eligibility for CAIR participation as the instrumental variable. The DID results indicate that the CAIR program was able to reduce NOx emissions from affected facilities by about 10% more than facilities who did not participate in the CAIR program. Therefore, CAIR achieves excellent overall performance in emissions reduction. The IV regression results also indicate that compared with non-CAIR facilities, purchasing emission permits still decreases a CAIR participating facility’s emissions level significantly. This result implies that even buyers under the cap-and-trade program have achieved a great amount of emissions reduction. Therefore, we conclude little evidence of environmental injustice from the CAIR program.

Keywords: air pollution, cap-and-trade, emissions trading, environmental justice

Procedia PDF Downloads 150
188 Cyclic Etching Process Using Inductively Coupled Plasma for Polycrystalline Diamond on AlGaN/GaN Heterostructure

Authors: Haolun Sun, Ping Wang, Mei Wu, Meng Zhang, Bin Hou, Ling Yang, Xiaohua Ma, Yue Hao

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Gallium nitride (GaN) is an attractive material for next-generation power devices. It is noted that the performance of GaN-based high electron mobility transistors (HEMTs) is always limited by the self-heating effect. In response to the problem, integrating devices with polycrystalline diamond (PCD) has been demonstrated to be an efficient way to alleviate the self-heating issue of the GaN-based HEMTs. Among all the heat-spreading schemes, using PCD to cap the epitaxial layer before the HEMTs process is one of the most effective schemes. Now, the mainstream method of fabricating the PCD-capped HEMTs is to deposit the diamond heat-spreading layer on the AlGaN surface, which is covered by a thin nucleation dielectric/passivation layer. To achieve the pattern etching of the diamond heat spreader and device preparation, we selected SiN as the hard mask for diamond etching, which was deposited by plasma-enhanced chemical vapor deposition (PECVD). The conventional diamond etching method first uses F-based etching to remove the SiN from the special window region, followed by using O₂/Ar plasma to etch the diamond. However, the results of the scanning electron microscope (SEM) and focused ion beam microscopy (FIB) show that there are lots of diamond pillars on the etched diamond surface. Through our study, we found that it was caused by the high roughness of the diamond surface and the existence of the overlap between the diamond grains, which makes the etching of the SiN hard mask insufficient and leaves micro-masks on the diamond surface. Thus, a cyclic etching method was proposed to solve the problem of the residual SiN, which was left in the F-based etching. We used F-based etching during the first step to remove the SiN hard mask in the specific region; then, the O₂/Ar plasma was introduced to etch the diamond in the corresponding region. These two etching steps were set as one cycle. After the first cycle, we further used cyclic etching to clear the pillars, in which the F-based etching was used to remove the residual SiN, and then the O₂/Ar plasma was used to etch the diamond. Whether to take the next cyclic etching depends on whether there are still SiN micro-masks left. By using this method, we eventually achieved the self-terminated etching of the diamond and the smooth surface after the etching. These results demonstrate that the cyclic etching method can be successfully applied to the integrated preparation of polycrystalline diamond thin films and GaN HEMTs.

Keywords: AlGaN/GaN heterojunction, O₂/Ar plasma, cyclic etching, polycrystalline diamond

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187 Molecular Alterations Shed Light on Alteration of Methionine Metabolism in Gastric Intestinal Metaplesia; Insight for Treatment Approach

Authors: Nigatu Tadesse, Ying Liu, Juan Li, Hong Ming Liu

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Gastric carcinogenesis is a lengthy process of histopathological transition from normal to atrophic gastritis (AG) to intestinal metaplasia (GIM), dysplasia toward gastric cancer (GC). The stage of GIM identified as precancerous lesions with resistance to H-pylori eradication and recurrence after endoscopic surgical resection therapies. GIM divided in to two morphologically distinct phenotypes such as complete GIM bearing intestinal type morphology whereas the incomplete type has colonic type morphology. The incomplete type GIM considered to be the greatest risk factor for the development of GC. Studies indicated the expression of the caudal type homeobox 2 (CDX2) gene is responsible for the development of complete GIM but its progressive downregulation from incomplete metaplasia toward advanced GC identified as the risk for IM progression and neoplastic transformation. The downregulation of CDX2 gene have promoted cell growth and proliferation in gastric and colon cancers and ascribed in chemo-treatment inefficacies. CDX2 downregulated through promoter region hypermethylation in which the methylation frequency positively correlated with the dietary history of the patients, suggesting the role of diet as methyl carbon donor sources such as methionine. However, the metabolism of exogenous methionine is yet unclear. Targeting exogenous methionine metabolism has become a promising approach to limits tumor cell growth, proliferation and progression and increase treatment outcome. This review article discusses molecular alterations that could shed light on the potential of exogenous methionine metabolisms, such as gut microbiota alteration as sources of methionine to host cells, metabolic pathway signaling via PI3K/AKt/mTORC1-c-MYC to rewire exogenous methionine and signature of increased gene methylation index, cell growth and proliferation in GIM, with insights to new treatment avenue via targeting methionine metabolism, and the need for future integrated studies on molecular alterations and metabolomics to uncover altered methionine metabolism and characterization of CDX2 methylation in gastric intestinal metaplasia for potential therapeutic exploitation.

Keywords: altered methionine metabolism, Intestinal metaplesia, CDX2 gene, gastric cancer

Procedia PDF Downloads 86
186 The Morphological Changes of POV in Diabetic Patients and Its Correlation with Changes in Corneal Epithelium, Corneal Nerve, and the Fundus in Using Vivo Confocal Microscopy

Authors: Ji Jiazheng, Wang Jingrao, Jin Xin, Zhang Hong

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Diabetes mellitus is a metabolic disease characterized by high blood sugar. A long-standing hyperglycemic state can lead to various tissue damage. Diabetic retinopathy is the most common and widely studied ocular complication and has become the leading cause of blindness in my country. At the same time, diabetes has profound clinically relevant effects on the cornea, leading to keratopathy and vision-threatening. The cornea is an avascular tissue and is sensitive to hyperglycemia, Keratopathy caused by diabetes is usually chronic, they are called diabetic keratopathy or diabetic neurotrophic keratopathy, leading to several diabetic corneal complications including delayed epithelial wound healing, recurrent erosions, neuropathy, loss of sensitivity. Corneal stem cell dysfunction in diabetic patients as an important influencing factor of diabetic keratopathy. The consequences of this condition are often underestimated. The limbus is located between the cornea and the sclera tissue. The limbal stroma consists of a series of radial elevations with fibrovascular centers known as palisades of Vogt (POV). Previous studies have shown that palisades of Vogt (POV), as the main site of limbal stem cells, plays an important role in the homeostasis of the corneal epithelium. Therefore, POV plays a vital role in the healing of corneal epithelial surgery and postoperative evaluation. IVCM can observe the condition of the corneal epithelium at the cellular level. It has profound significance and guidance for the evaluation of limbal and limbal stem cells. We have previously observed structural changes in POV in HSK and HZO patients on IVCM. At present, there have been reports involving limbal stem cell dysfunction in diabetic patients, but the specific pathogenesis is still unclear. However, there are no studies on POV morphological changes in patients with DM. Therefore, we performed statistics and compared the correlation between POV morphological changes and corneal epithelial basal cell density, corneal nerves, and length of disease in DM patients and normal humans using IVCM studies. At the same time, fundoscopy was used to observe the correlation between the thickness of RNFL and the thickness of GCC and POV in diabetic patients. And to observe the correlation between SVD, DVD and POV for research.

Keywords: confocal microscopy, fundus, limbal stem cells, diabetes

Procedia PDF Downloads 83
185 The Preceptorship Experience and Clinical Competence of Final Year Nursing Students

Authors: Susan Ka Yee Chow

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Effective clinical preceptorship is affecting students’ competence and fostering their growth in applying theoretical knowledge and skills in clinical settings. Any difference between the expected and actual learning experience will reduce nursing students’ interest in clinical practices and having a negative consequence with their clinical performance. This cross-sectional study is an attempt to compare the differences between preferred and actual preceptorship experience of final year nursing students, and to examine the relationship between the actual preceptorship experience and perceived clinical competence of the students in a tertiary institution. Participants of the study were final year bachelor nursing students of a self-financing tertiary institution in Hong Kong. The instruments used to measure the effectiveness of clinical preceptorship was developed by the participating institution. The scale consisted of five items in a 5-point likert scale. The questions including goals development, critical thinking, learning objectives, asking questions and providing feedback to students. The “Clinical Competence Questionnaire” by Liou & Cheng (2014) was used to examine students’ perceived clinical competences. The scale consisted of 47 items categorized into four domains, namely nursing professional behaviours; skill competence: general performance; skill competence: core nursing skills and skill competence: advanced nursing skills. There were 193 questionnaires returned with a response rate of 89%. The paired t-test was used to compare the differences between preferred and actual preceptorship experiences of students. The results showed significant differences (p<0.001) for the five questions. The mean for the preferred scores is higher than the actual scores resulting statistically significance. The maximum mean difference was accepted goal and the highest mean different was giving feedback. The Pearson Correlation Coefficient was used to examine the relationship. The results showed moderate correlations between nursing professional behaviours with asking questions and providing feedback. Providing useful feedback to students is having moderate correlations with all domains of the Clinical Competence Questionnaire (r=0.269 – 0.345). It is concluded that nursing students do not have a positive perception of the clinical preceptorship. Their perceptions are significantly different from their expected preceptorship. If students were given more opportunities to ask questions in a pedagogical atmosphere, their perceived clinical competence and learning outcomes could be improved as a result.

Keywords: clinical preceptor, clinical competence, clinical practicum, nursing students

Procedia PDF Downloads 127
184 Understanding the Basics of Information Security: An Act of Defense

Authors: Sharon Q. Yang, Robert J. Congleton

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Information security is a broad concept that covers any issues and concerns about the proper access and use of information on the Internet, including measures and procedures to protect intellectual property and private data from illegal access and online theft; the act of hacking; and any defensive technologies that contest such cybercrimes. As more research and commercial activities are conducted online, cybercrimes have increased significantly, putting sensitive information at risk. Information security has become critically important for organizations and private citizens alike. Hackers scan for network vulnerabilities on the Internet and steal data whenever they can. Cybercrimes disrupt our daily life, cause financial losses, and instigate fear in the public. Since the start of the pandemic, most data related cybercrimes targets have been either financial or health information from companies and organizations. Libraries also should have a high interest in understanding and adopting information security methods to protect their patron data and copyrighted materials. But according to information security professionals, higher education and cultural organizations, including their libraries, are the least prepared entities for cyberattacks. One recent example is that of Steven’s Institute of Technology in New Jersey in the US, which had its network hacked in 2020, with the hackers demanding a ransom. As a result, the network of the college was down for two months, causing serious financial loss. There are other cases where libraries, colleges, and universities have been targeted for data breaches. In order to build an effective defense, we need to understand the most common types of cybercrimes, including phishing, whaling, social engineering, distributed denial of service (DDoS) attacks, malware and ransomware, and hacker profiles. Our research will focus on each hacking technique and related defense measures; and the social background and reasons/purpose of hacker and hacking. Our research shows that hacking techniques will continue to evolve as new applications, housing information, and data on the Internet continue to be developed. Some cybercrimes can be stopped with effective measures, while others present challenges. It is vital that people understand what they face and the consequences when not prepared.

Keywords: cybercrimes, hacking technologies, higher education, information security, libraries

Procedia PDF Downloads 134
183 Randomized Trial of Tian Jiu Therapy in San Fu Days for Patients with Chronic Asthma

Authors: Libing Zhu, Waichung Chen, Kwaicing Lo, Lei Li

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Background: Tian Jiu Therapy (a medicinal vesiculation therapy according to traditional Chinese medicine theory) in San Fu Days (the three hottest days in a year is calculated by the Chinese ancient calendar) is widely used by patients with chronic asthma in China although from modern medicine perspective there is insufficient evidence of its effectiveness and safety issues. We investigated the efficacy and safety of Tian Jiu Therapy compared with placebo in patients with chronic asthma. Methods: Patients with chronic asthma were randomly assigned to Tian Jiu treatment group (n=165), placebo control group (n=158). Registered Chinese Medicine practitioners, in Orthopedics-Traumatology, Acupuncture, and Tui-na Clinical Centre for Teaching and Research, School of Chinese Medicine, The University of Hong Kong, administered Tian Jiu Therapy and placebo treatment in 3 times over 2 months. Patients completed questionnaires and lung function test before treatment and after treatment, 3, 6, 9, and 11 months, respectively. The primary outcome was the no of asthma-related sub-healthy symptoms and the percentage of patients with twenty-three symptoms. Results: 451 patients were recruited totally, 111 patients refused or did not participate according the appointment time and 17 did not meet the inclusion criteria. Consequently, 323 of eligible patients were enrolled. There was nothing difference between Tian Jiu Therapy group and placebo control group at the end of all treatments neither primary nor secondary outcomes. While Tian Jiu Therapy as compared with placebo significantly reduced the percentage of participants who are susceptible waken up by asthma symptoms from 27% to 14% at 2nd follow-up (P < 0.05). Similarly, Tian Jiu Therapy significantly reduced the proportion of participants who had the symptom of running nose and sneezing before onset from 18% to 8% at 2nd follow-up (P < 0.05). Additionally, Tian Jiu Therapy significantly reduced the level of asthma, the proportion of participants who don’t need to processed during asthma attack increased from 6% to 15% at 1st follow-up and 0% to 7% at 3rd follow-up (P < 0.05). Improvements also occurred with Tian Jiu Therapy group, it reduced the proportion of participants who were spontaneously sweating at 3rd follow up and diarrhea after intake of oily food at 4th follow-up (P < 0.05). Conclusion: When added to a regimen of foundational therapy for chronic asthma participants, Tian Jiu Therapy further reduced the need for medications to control asthma, improved the quality of participants’ life, and significantly reduced the level of asthma. What is more, this benefit seems to have an accumulative effect over time was in accordance with the TCM theory of 'winter disease is being cured in summer'.

Keywords: asthma, Tian Jiu Therapy, San Fu Days, triaditional Chinese medicine, clinical trial

Procedia PDF Downloads 314
182 The Risk and Prevention of Peer-To-Peer Network Lending in China

Authors: Zhizhong Yuan, Lili Wang, Chenya Zheng, Wuqi Yang

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How to encourage and support peer-to-peer (P2P) network lending, and effectively monitor the risk of P2P network lending, has become the focus of the Chinese government departments, industrialists, experts and scholars in recent years. The reason is that this convenient online micro-credit service brings a series of credit risks and other issues. Avoiding the risks brought by the P2P network lending model, it can better play a benign role and help China's small and medium-sized private enterprises with vigorous development to solve the capital needs; otherwise, it will bring confusion to the normal financial order. As a form of financial services, P2P network lending has injected new blood into China's non-government finance in the past ten years, and has found a way out for idle funds and made up for the shortage of traditional financial services in China. However, it lacks feasible measures in credit evaluation and government supervision. This paper collects a large amount of data about P2P network lending of China. The data collection comes from the official media of the Chinese government, the public achievements of existing researchers and the analysis and collation of correlation data by the authors. The research content of this paper includes literature review; the current situation of China's P2P network lending development; the risk analysis of P2P network lending in China; the risk prevention strategy of P2P network lending in China. The focus of this paper is to try to find a specific program to strengthen supervision and avoid risks from the perspective of government regulators, operators of P2P network lending platform, investors and users of funds. These main measures include: China needs to develop self-discipline organization of P2P network lending industry and formulate self-discipline norms as soon as possible; establish a regular information disclosure system of P2P network lending platform; establish censorship of credit rating of borrowers; rectify the P2P network lending platform in compliance through the implementation of bank deposition. The results and solutions will benefit all the P2P network lending platforms, creditors, debtors, bankers, independent auditors and government agencies of China and other countries.

Keywords: peer-to-peer(P2P), regulation, risk prevention, supervision

Procedia PDF Downloads 166
181 Understanding the Coping Experience of Mothers with Childhood Trauma Histories: A Qualitative Study

Authors: Chan Yan Nok

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The present study is a qualitative study based on the coping experiences of six Hong Kong Chinese mothers who had childhood trauma from their first-person perspective. Expanding the perspective beyond the dominant discourse of “inter-generation transmission of trauma”, this study explores the experiences and meanings of child trauma embedded in their narratives through the process of thematic analysis and narrative analysis. The interviewees painted a nuanced picture of their process of coping and trauma resolution. First, acknowledgement; second, feel safe and start to tell the story of trauma; third, feel the feelings and expression of emotions; fourth, clarifying and coping with the impacts of trauma; fifth, integration and transformation; and sixth, using their new understanding of experience to have a better life. It was seen that there was no “end” within the process of trauma resolution. Instead, this is an ongoing process with positive healing trajectory. Analysis of the stories of the mothers revealed recurrent themes around continuous self-reflective awareness in the process of trauma coping. Rather than being necessarily negative and detrimental, childhood trauma could highlight the meanings of being a mother and reveal opportunities for continuous personal growth and self-enhancement. Utilizing the sense of inadequacy as a core driver in the trauma recovery process while developing a heightened awareness of the unfinished business embedded in their “automatic pattern” of behaviors, emotions, and thoughts can help these mothers become more flexible to formulate new methods in facing future predicaments. Future social work and parent education practices should help mothers deal with unresolved trauma, make sense of their impacts of childhood trauma and discover the growth embedded in the past traumatic experience. They should be facilitated in “acknowledging the reality of the trauma”, including understanding their complicated emotions arising from the traumatic experiences and voicing their struggles. In addition, helping these mothers to be aware of short-term and long-term trauma impacts (i.e., secondary responses to the trauma) and explore their effective coping strategies in “overcoming secondary responses to the trauma” are crucial for their future positive adjustment and transformation. Through affirming their coping abilities and lessons learnt from past experiences, mothers can reduce feelings of shame and powerlessness and enhance their parental capacity.

Keywords: childhood trauma, coping, mothers, self-awareness, self-reflection, trauma resolution

Procedia PDF Downloads 165