157 research outputs found
Social Networks along the Migration Cycle between Vietnam and Korea: Opportunities or Obstacles for Temporary Labour Migrants?
This thesis offers a comprehensive analysis of social networks applied to the specific case of temporary contract migration in an intra-regional (here, Asian) context. Although intra-Asian labour migration has been of increasing scholarly concern, the majority of such studies have focused on the economic and political aspects of migration, often in relation to development, to the exclusion of social networks for migrant workers. Given the significant impact of networks on the success of temporary migration for the individual migrants and their families, this thesis addresses important gaps in the study of international labour migration as well as the study of social networks. This thesis’ specific contribution is the provision of a comprehensive analysis of the roles and characteristics of social networks in relation to their spatiality and temporality, conceptually explored via social capital theory and network-based theory of social capital, and empirically informed via the case of temporary labour migration from Vietnam to South Korea. It approaches this topic by examining (1) how changes to the regulatory framework of contract labour migration between Vietnam and South Korea have resulted in the transformation of migrants’ agency, reflected in the forming and joining of different kinds of networks; (2) the advantages and downsides of the various types of networks involved at different stages of the ‘migration project’; (3) the complexity and changeability of networks engaged in assisting migrants along the entire migration cycle; and (4) the gendered aspects involved in these processes and dynamics. The study relies on a mix of qualitative methodologies in which individual migrant workers are the key units of analysis. The methods for data generation are in-depth interviews and participant observation from fieldwork conducted in Vietnam and South Korea in 2013 and 2015. The findings show that social networks of and for Vietnamese migrant workers, including interpersonal and institutional, are complex and varied. The fundamental purpose of migrant workers generally is to maximise their earnings during a short period of time; they attempt to seek support from different social networks during different phases of their migration. However, not all social networks are supportive and beneficial to the migrants. Some social networks provide opportunities for migrant workers to achieve their goals, while others might aim at exploiting these workers. In other words, assistance can be given free or bought at high costs. Trust and norms of reciprocity exist only among bonding ties, not on a larger scale such as among an entire co-ethnic migrant community. The study also points out that, due to gender segregation of the Korean labour market, men have more opportunities to find a job in this country by contract-based visas, while jobs for women are more limited than their male counterparts. This results in less access to institutional networks for female migrant workers. Since South Korea temporarily suspended contract-based migration from Vietnam, Vietnamese workers have moved to South Korea through other types of visas. The existence of alternative channels for migration to South Korea has gender implications with regard to the type of networks used: male prospective migrants tend to migrate to South Korea through overseas study or trading, whilst their female counterparts find it is easier to enter South Korea through sham marriages or cosmetic surgery. Finally, the study demonstrates the dynamism and the changing nature of social networks that migrants use throughout the migration cycle. Over time, migrants expand their networks locally and transnationally. In addition, the roles of the same networks and the position of migrant workers in these networks may change during different phases of migration. In the case of policies on recruitment of Vietnamese workers for the Korean labour market are often changed, the changing nature of networks also performs in the flexibility of formation of new networks serving for different channels of migration. This unique change of networks reflects is specific policy context of migration between Vietnam and South Korea for making money
E-GROCERY MARKET IN JAPAN: HOW SMALL NEW PLAYERS COMPETE WITH THE GIANTS A business model analysis of Honestbee
ROLE OF THE Na,K-ATPase IN POLYCYSTIC KIDNEY DISEASE
Autosomal dominant polycystic kidney disease (ADPKD) is the most common monogenic disease, and is characterized by multiple fluid-filled cysts that impair the organ, ultimately leading to renal failure. Formation and enlargement of the cysts require abnormal proliferation and cell death, as well as changes in the transport properties of the renal tubule epithelial cells. Because of its primary role in the vectorial movement of salt and water in the kidney, the Na,K-ATPase has been the focus of investigation to understand the pathophysiology of ADPKD. However, the precise role of the transporter has not been identified. In this dissertation, we describe studies designed to characterize the Na,K-ATPase in ADPKD, and examine the mechanisms underlying its role in the disease. The transport properties of the Na,K-ATPase is regulated by the hormone ouabain, which inhibits its movement of the cations. In addition, ouabain binding to the Na,K-ATPase has been been found to activate a cascade of phosphorylating events, leading to cell growth. Interestingly, we have found a population of the Na,K-ATPase in human cystic epithelial cells to have a higher affinity for ouabain, at concentrations consistent with circulating levels of the hormone. Thus, nanomolar concentrations of ouabain that do not normally affect the activity of the Na,K-ATPase in the kidney partially inhibit the enzyme of cystic tissue and cells. The Na,K-ATPase has been found to interact with polycystin-1, and we have found this to association to increase the sensitivity of the enzyme to ouabain. Our hypothesis is that due to their increased sensitivity to the hormone in ADPKD, the cystic renal epithelium is more susceptible to the effects of endogenous ouabain. We found ouabain to stimulate both proliferation and apoptotic death of the ADPKD cells, causing a disbalance that favors increased cell growth. While the mitogenic effect of ouabain is mediated by activation of the epidermal growth factor receptor (EGFR), Src kinase and extracellular signal-regulated kinase (ERK) pathway, its apoptotic effect was found to be through activation of the intrinsic pathway of apoptotic cell death. We also found ouabain to exacerbate the development and growth of cysts, both in cultured human ADPKD cells and metanephric organ cultures from Pkd1m1Bei mice, a well characterized model of ADPKD. Collectively, these results demonstrate ouabain, acting through the Na,K-ATPase, is a novel agent that can adversely affect the progression of ADPKD
Innovations in Water Management for Sustainable Development of Higher Education Institutions: Experience from Ton Duc Thang University, Vietnam
Ton Duc Thang University (TDTU), which was established in 1997, is a fully autonomous public university in Vietnam. After over 22 years of development, TDTU is now the number one university in Vietnam for all aspects. In 2019, TDTU was ranked the 1st in Vietnam and ranked 165th in the world on sustainable development by UI GreenMetric World University Rankings (UI GreenMetric). Among six categories of UI GreenMetric, including: setting and infrastructure, energy and climate change, waste, water, transport, and education, the water category of TDTU achieved 725 points out of 1000 maximum points (72.50%). This paper presents water management of TDTU, focusing on water conservation, water recycling, the use of water efficient appliances and piped water consumption. Specifically, the paper highlights innovations in water management that TDTU has implemented during the past few years. The paper concludes that sustainable water management makes great contribution to sustainable development of a higher education institutio
FACTORS AFFECTING THE SHARE OF FAKE NEWS ABOUT COVID-19 OUTBREAK ON SOCIAL NETWORKS IN VIETNAM
In recent days in Vietnam, the amount of fake news spreading online about the Covid-19 epidemic has shown signs of increasing, causing information confusion and complicating the situation. This fact has received significant attention from scientists. To supplement the evidence of previous studies, enrich the research literature and make policy recommendations to the Government, this study explores the factors influencing the sharing of fake news on social networks. This study was conducted through a cross-sectional survey using an intentional sampling technique (n = 200) multivariate linear regression analysis technique was applied to prove the hypotheses. Research results show that the factors of altruism, entertainment, socialization, self-promotion, and instant information sharing have a positive and meaningful impact on sharing fake news about Covid_19 on social networks
Disturbance observer-based controller for inverted pendulum with uncertainties: Linear matrix inequality approach
A new approach based on linear matrix inequality (LMI) technique for stabilizing the inverted pendulum is developed in this article. The unknown states are estimated as well as the system is stabilized simultaneously by employing the observer-based controller. In addition, the impacts of the uncertainties are taken into consideration in this paper. Unlike the previous studies, the uncertainties in this study are unnecessary to satisfy the bounded constraints. These uncertainties will be converted into the unknown input disturbances, and then a disturbance observer-based controller will be synthesized to estimate the information of the unknown states, eliminate completely the effects of the uncertainties, and stabilize inverted pendulum system. With the support of lyapunov methodology, the conditions for constructing the observer and controller under the framework of linear matrix inequalities (LMIs) are derived in main theorems. Finally, the simulations for system with and without uncertainties are exhibited to show the merit and effectiveness of the proposed methods
Human exposure to radon radiation geohazard in Rong Cave, Dong Van Karst Plateau Geopark, Vietnam
Rong Cave is one of the more important caves in northern Vietnam’s Dong Van Karst Plateau Geopark (part of the Global Geoparks Network), because its subterranean lake provides agricultural and domestic water for neighboring communities. Maintenance and utilization of Rong Cave’s water reservoir, as well as touristic cave use, require frequent human access to Rong Cave. Depending on the availability of seasonal drip water and the water level of the lake, the abundant clay-rich sediment in the back portion of Rong Cave and possible seepage of gas from deeper strata along geologic faults provide seasonally elevated concentrations of radon in cave air. Based on repeated measurements over 10 months in 2015 and 2016 of the concentrations of radon isotopes (222Rn and 220Rn, also called thoron) with a portable SARAD® RTM 2200 instrument (SARAD® GmbH, Germany), the human total annual inhalation dose was estimated according to the UNSCEAR (2000) algorithm. The result indicates that the radon-related radiation exposure is insignificant for short-term visitors but may reach ~1.8 mSv a-1 for tour guides and ~25 mSv a-1 for cave utility workers. The latter values exceed the IAEA-recommended safety threshold of 1 mSv a-1 (IAEA, 1996). We recommend radiation monitoring for cave utility workers and tour guides. Prolonged human presence in Rong Cave should be avoided during periods of seasonally elevated radon concentrations.References Cigna A.A., 2005. Radon in caves. Interna-tional Journal of Speleology 34(1-2), 1-18. Ha Giang Statistics Office (GSO), 2016. Statistical Yearbook of Ha Giang 2015, 404 pages, Ha Giang (in Vietnamese). Dumitru O.A., Onac B.P., Fornós J.J., Cosma C., Ginés A., Ginés J., Merino A., 2015. Radon survey in caves from Mallorca Island, Spain. Science of The Total Environment, 526, 196-203. Etiope G., Martinelli G., 2002. Migration of carrier and trace gases in the geosphere: An overview. 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International Commission on Radiological Protection (ICRP), 2010. Lung cancer risk from radon and progeny and Statement of radon. ICPR Pub. 115. Ann. ICPR 40(1). Markkanen M., Arvela H., 1992. Radon emanation from soils. Radiation Protection Dosimetry, 45(1-4), 269-272. Meisenberg O., Mishra R., Joshi M., Gierl S., Rout R., Guo L., Agaarwwal T., Kanse S., Irlinger J., Sapra B.K., Tschiersch J., 2017. Radon and thoron inhalation doses in dwellings with earthen architecture: Comparison of measurement methods. Science of The Total Environment, 579, 1855-1862. Morawska L., Phillips C.R., 1993. Depend-ence of the radon emanation coefficient on radium distribution and internal structure of the material, Geochimica et Cosmochimica Acta, 57(8), 1783-1797. Nguyen Thuy Duong, Nguyen Van Huong, Arndt Schimmelmann, Nguyen Thi Anh Nguyet, Dang Thi Phuong Thao, Ta Hoa Phuong, 2016. Radon concentrations in karst caves in Dong Van karst plat-eau. 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Soil-gas monitoring: A tool for fault delineation studies along Hsinhua Fault (Tainan), Southern Taiwan. Applied Geochemistry, 25(4), 602-607. Wang J., Meisenberg O., Chen Y., Karg E., Tschiersch J., 2011. Mitigation of radon and thoron decay products by filtration. Science of The Total Environment, 409(19), 3613-3619. World Health Organization (WHO), 2000. Air Quality Guidelines for Europe, (2nd edition). WHO Regional Publications, European Series, 91, Chapter 8.3 - Radon
Application of the cut-off projection to solve a backward heat conduction problem in a two-slab composite system
The main goal of this paper is applying the cut-off projection for solving one-dimensional backward heat conduction problem in a two-slab system with a perfect contact. In a constructive manner, we commence by demonstrating the Fourier-based solution that contains the drastic growth due to the high-frequency nature of the Fourier series. Such instability leads to the need of studying the projection method where the cut-off approach is derived consistently. In the theoretical framework, the first two objectives are to construct the regularized problem and prove its stability for each noise level. Our second interest is estimating the error in -norm. Another supplementary objective is computing the eigen-elements. All in all, this paper can be considered as a preliminary attempt to solve the heating/cooling of a two-slab composite system backward in time. Several numerical tests are provided to corroborate the qualitative analysis.Peer reviewe
Using learning games for fourth-grade students to teach Vietnamese lessons and teachers' perspectives on learning games
Students can learn in a meaningful way through the use of educational games. When students apply their skills and information in order to progress through a game, a huge degree of engagement is generated among them in the classroom as a result both their capabilities and their learning increase. 153 children from primary schools in Vietnam participated in this research. The children were split into two groups: an experimental and a control group. Both groups participated in two sessions of word and sentence practice as well as spelling instruction. According to the findings of the study, the educational outcomes of the students are greatly improved when games are used in their classrooms. In addition, research has shown that some teachers are against the use of games in the classroom since it makes it more difficult to prepare educational materials. Some educators believe that playing educational games is a more effective method of instruction as it allows for greater flexibility during the learning process. This makes a contribution to the theoretical framework that is necessary to guide educators and instructors in the process of improving learning game programs for children in primary schools and other learners
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