Coastal vulnerability assessment: a case study in Kien Giang, western part of the Mekong River Delta in Vietnam

Climate change, particularly sea-level rise, threatens low-lying coastal systems, such as small islands on coral atolls, and deltas where millions of people are living. The Mekong River Delta is considered especially at risk. Although most of the delta is only a few metres above sea level, there have been few assessments of vulnerability at local scale. The aim of this thesis is to provide quantitative and qualitative information to guide the process of adaptation and provide visualisations that will enhance local authority’s decision making to adapt to climate change, particularly sea-level rise. It focuses on the seven coastal districts within Kien Giang province in the western, micro-tidal section of the delta. A framework is adopted that integrates biophysical effects and socioeconomic stressors for the case study area and consists of three main components of vulnerability: exposure, sensitivity, and adaptive capacity. The analytical hierarchical process (AHP) method of multi-criteria decision making was integrated directly into a geographic information system (GIS) to derive a composite vulnerability index that indicated areas or hotspots most likely to be vulnerable to sea-level rise. The hierarchical structure comprised three components: exposure, sensitivity and adaptive capacity (level 1); and eight sub-components (level 2): seawater incursion, flood risk, shoreline change, population characteristics, landuse, as well as socioeconomic, infrastructure, and technological capability. The Digital Shoreline Analysis System (DSAS) tool was used to calculate rates of shoreline change along the Kien Giang coast over time in order to derive the shoreline change sub-component that contributed to the exposure component. Beyond this, a further 22 variables (level 3) and 24 sub-variables (level 4) related to vulnerability were also mapped. Based on the weights of variables derived from AHP pair-wise comparisons, a final map was generated to visualise areas reported into five categories of relative vulnerability; very low, low, moderate, high to very high vulnerability. Several regional patterns emerged. Relatively high exposure to seawater incursion, flood risk, and moderate loss of mangroves characterised the coastal fringe of each district. Those areas found to be most sensitive tended to have moderate population density, generally with a large rural population and high proportions of ethnic households with limited availability of agricultural land. Many aspects of adaptive capacity could only be represented at district scale, with the least adaptable areas consisting of large proportions of poor households, low income, and moderate densities of transport, irrigation, and drainage systems. Finally, most coastal districts were determined to be of moderate to relatively high vulnerability, with scattered hotspots along the Kien Giang coast, which coincided with settlement areas. The results obtained, enable identification and prioritisation of the areas, or hotspots most likely to be vulnerable, for which site-specific assessments might further assist the local authorities and communities in better coastal management and conservation. However, the limitations of data accessible at an entire district can influence the outcome. Social vulnerability remains a challenge because it is changing over time and space

STAKEHOLDER INVOLVEMENT IN DESTINATION MARKETING: A NETWORK ANALYSIS OF TWO DESTINATIONS IN VIETNAM

Purpose –This paper aims to identify the stakeholders involved in tourism destination marketing networks. The involvement and collaboration of multiple individuals and organisations is widely recognised in destination marketing to promote a destination. Internal stakeholders of a destination and their collaboration are frequently studied in destination marketing research, but little attention is paid to the involvement of external stakeholders. Design/Methodology/Approach – Quantitative social network analysis is an important approach to understanding stakeholder connections and roles in tourism destinations. In this paper, this analysis was conducted using primary data collected from social network surveys in Da Nang and Hue, two local destinations in central Vietnam. Sixty-nine questionnaires were collected in Da Nang, and 60 questionnaires in Hue. The network data were each analysed separately using UCINET software. Findings – The results show the involvement of different stakeholders in marketing activities in these local destinations. Most of the marketing networks of Da Nang and Hue consist of business units. While the Da Nang marketing network focuses on critical stakeholders and fundamental business firms with strong financial resources and big brands, the Hue marketing network includes more diverse stakeholders and more significant participation of small and medium local firms. Originality of research – This research found the participation of national and international stakeholders located outside the two destinations studied in their marketing network. Their involvement was identified through their collaborative relationships with the DMOs and internal stakeholders of the two destinations to promote the destinations nationally and internationally

Detection of Luminescence Centers in Colloidal Cd0.3_{0.3}Zn0.7_{0.7}S Nanocrystals by Synchronous Luminescence Spectroscopy

With the advantages of selectivity, spectral resolution and reduction of interference on account of light scattering, synchronous luminescence spectroscopy (SLS) is successfully applied to analyze complex mixtures with overlapped emission and/or excitation spectra. In fact, it is difficult to clearly distinguish the contributions of various luminescence centers to low-energy band of semiconductor nanocrystals (NCs). Herein, we report the application of SLS method to detect luminescence centers in colloidal Cdsub0.3/subZnsub0.7/subS NCs. Their conventional luminescence and synchronous luminescence spectra were comparatively investigated. Differently from conventional luminescence spectrum, the emission peaks at 460 and 515 nm were found using SLS method. They are attributed to the emission transitions related to sulfur and zinc/cadmium vacancies. The obtained results are useful to clarify the nature of luminescence centers as well as relaxation mechanism in Cdsubx/subZnsub1-x/subS NCs

PREPARATION AND FTIR STUDIES OF PMMA/PVC POLYMER BLENDS, PVC-g-PMMA GRAFT COPOLYMERS AND EVALUATING GRAFT CONTENT

This study presents the qualitative and quantitative analyses of Fourier Transform Infrared (FTIR) spectra of poly(methyl methacrylate)/poly(vinyl chloride) blends (PMMA/PVC), as well as PVC-g-PMMA graft copolymers. Graft copolymerizations of methyl mathacrylate (MMA) onto PVC macromolecules were carried out mixture of cyclohexanone/N,N-dimethylformamide as solvents, dibenzoyl peroxide as initiator and nitrogen medium. FTIR spectra of PMMA/PVC blends showed that there were molecular interactions between C=O groups of PMMA and C-Cl groups of PVC. Assignments of infrared absorption bands for specific groups of PMMA/PVC blends have been contributed. Using regression method, linear calibration curve between PMMA mole content and peak areas of C=O groups in FTIR spectra of the blends has been found when C=O peak areas were multiplied by an appropriate factor. PMMA grafted content and total PMMA formed content in PVC-g-PMMA graft copolymers have been evaluated. The results showed that grafted PMMA content was increased since PVC was initiatly dechlorinated by NaOH solution. The grafted PMMA content and total formed PMMA content were 5.05 wt.% and 11.25 wt.% respectively when MMA monomers were grafted onto neat PVC and modified PVC molecules

Simple thermal-electrical model of photovoltaic panels with cooler-integrated sun tracker

This paper presents a simple thermal-electrical model of a photovoltaic panel with a cooler-integrated sun tracker. Based on the model and obtained weather data, we analyzed the improved overall efficiency in a year as well as the performance in each typical weather case for photovoltaic panels with fixed-tilt systems with a tilt angle equal to latitude, fixed-tilt systems with cooler, a single-axis sun tracker, and a cooler-integrated single-axis sun tracker. The results show that on a sunny summer day with few clouds, the performance of the photovoltaic panels with the proposed system improved and reached 32.76% compared with the fixed-tilt systems. On a sunny day with clouds in the wet, rainy season, because of the low air temperature and the high wind speed, the photovoltaic panel temperature was lower than the cooler’s initial set temperature; the performance of the photovoltaic panel with the proposed system improved by 12.55% compared with the fixed-tilt system. Simulation results show that, over one year, the overall efficiency of the proposed system markedly improved by 16.35, 13.03, and 3.68% compared with the photovoltaic panel with the fixed-tilt system, the cooler, and the single-axis sun tracker, respectively. The simulation results can serve as a premise for future experimental models

Biosafety knowledge and perception among medical laboratory students: a cross-sectional study at a medical university in Vietnam

Introduction: Medical students have to deal with biohazards in laboratories during undergraduate studies and intensive practice in hospitals. Unsafe operators can result in an outbreak of biohazardous pathogens to healthcare workers, the community, and the environment. However, the most common risk factors for laboratory accidents are a lack of perception and knowledge of biosafety and laboratory safety management. This study aimed to assess knowledge and factors influencing the biosafety practices of medical students at Hanoi Public Health University, Vietnam Methods: A cross-sectional study was conducted to assess the biosafety knowledge of all 286 students majoring in a medical laboratory at HUPH from December 2021 to February 2022. Ethical clearance was obtained from the Ethics Committee of Hanoi University of Public Health. The questionnaire has been created based on WHO biosafety guidelines with some modifications according to the local context. The data were collected by face-to-face interviews Results:: Out of the 286 students invited to complete a biosafety questionnaire, 68.6% of students recognized the fundamental principles of biosafety. Additionally, 76.2% and 91% of students correctly identified risk factors and danger signs in the laboratory, respectively. Furthermore, 79.8% of students provided accurate answers to biosafety laboratory troubleshooting questions. Notably, academic performance, students’ year of study, and average scores in biosafety courses had significantly related to the biosafety knowledge. Gender factors and academic performance were related to the rate of obtaining precise knowledge about incident handling and preventing risk factors in the laboratory. Conclusion: The passed rate of biosafety knowledge among medical laboratory students at the University of Public Health was 68.6%. Factors such as the student's school year, academic performance, average score in the biosafety course number of internships in hospitals significantly affected their biosafety and troubleshooting knowledge in the laboratory

Review and Evaluation of Agricultural Policies in Years 2015-2017

This journal article describes main results of the OECD Annual Report published in 2018, titled “Review and evaluation of agricultural policy in 2017” for 51 selected countries in the world, including Vietnam. The report is closely prepared by MARD and OECD experts. The journal article emphasizes more on Vietnam by updating and adjusting data, information and policies in 2017 and 2018. The description presents the changing trend of agricultural policies applied in the world, considering whether this trend is in the direction of achieving sustainable productivity growth, environmental protection, and adaptation to climate change. On average in the last 20 years, trend of world policies has been better but far to catch above purposes. The development of international trade has made the commodity movement more freely and price gaps narrowed between countries and regions. This trend made agricultural markets developed more toward reflecting the scarcity of good and services. Average level of total agricultural supports has been reducing. Consequently, the world price indices and the total support have been converted between countries and commodities. However, the total agricultural support reduction is mainly in developed countries like OECD countries. Emerging and developing countries have increased their agricultural supports. Relative to GDP, the level of the total agriculture support in Vietnam has been reducing.Inside the total agricultural support, producer supports accounted 78% while general service support accounted only for 14%. Inside the producer support, market price support accounted for more than 50% in many countries. Payments based on outputs and inputs also accounted more than 50% in many countries. In Vietnam, the producer support is very small, negative level in 2015 and 2016 and became positive in 2017 and 2018. The agricultural producer support in 2017 is about 900 million USD. In the overall service support, many countries mainly invest in infrastructure construction, for example in Japan and Vietnam over 70%, while investments in other items are too small, for example that in Vietnam is only about 16%.In conclusion, OECD suggests that market price support should be reduced and finally eliminated. Similarly, output and input payments should be reduced and eliminated. Future policies should focus on general support service that helps producers to achieve sustainable productivity growth in the context of a changing and uncertain climate. OECD especially emphasizes on appropriate investments in research, together with efforts to ensure that the outputs of this research reach farmers. OECD also emphasizes on research that help producers to better manage risks including business risk, weather risk, and climate changes. Agricultural production and climate changes are strongly interacted. Future research should be the better co-operation between public and private sectors with the leading role of public sector. The future research should be co-operated more strongly between countries and regions because of the differences in histories, cultures, geology and climate

Red light emission of Mn doped beta-tricalcium phosphate -Ca3(PO4)2

This paper is the first report on the red light emission of manganese (Mn) doped beta-tricalcium phosphate (b-Ca3(PO4)2, TCP) synthesis by co-precipitation method followed by thermal annealing. The annealed Mn doped TCP phosphor showed dominant spheres with a diameter of about 500 nm. The influences of the Mn concentration, annealing temperature, and atmospheres on the photoluminescence intensities of the phosphors were investigated and the results indicate that the annealing temperatures and Mn concentrations are the main factors. The phosphor showed visible emission peaks appeared at about 660 nm and 580 nm results in from the 4T1-6A1 transitions within Mn2+ ion. The Mn-TCP phosphor may serve as a candidate for light-emitting diode application in agriculture lighting. Keywords. Hydroxyapatite; manganese; luminescence; tricalcium phosphate

Risk factors of dengue fever in an urban area in Vietnam: a case-control study

BackgroundDengue is a mosquito-borne flavivirus present in many metropolitan cities of tropical countries.MethodsDuring and after the dengue season (September 2018 to January 2019), we conducted a case-control study in order to determine the risk factors for dengue fever in Hanoi city, Vietnam. 98 dengue patients and 99 patients with other acute infections, such as Hepatitis B virus infection, were recruited at Department of Infectious Disease of Bach Mai national hospital in Hanoi. Patients were interviewed using a structured questionnaire covering demographic, housing, environmental factors and knowledge, attitude, and practice on dengue prevention and control. Univariate analysis and multivariable logistic regression were used to determine the risk factors of dengue status.ResultsThe mean score of knowledge items and practice items was only 7.9 out of total 19 points and 3.9 out of total 17 points, respectively. While the mean score of attitude items was 4.8 out of total 6 points. Multivariable logistic regression indicated that older patients had lesser risk of getting dengue infection as compared to younger adults aged 16-30, and patients living in peri-urban districts were less likely to suffer of dengue fever than patients living in central urban districts (OR=0.31; 95% CI 0.13-0.75). This study could not find any association with occupation, water storage habit, knowledge, attitude, or practice on dengue prevention.ConclusionsAll patients had a relatively low level of knowledge and practice on dengue prevention and control. However, the attitude of the participants was good. We found that age group and living district were the risk factors correlated with the dengue status. Communication programs on raising dengue awareness should be repeated all year round and target particular groups of adolescents, younger adults, landlords and migrants from other provinces to improve their knowledge and encourage them to implement preventive measures against dengue fever

Information searching behaviors among Vietnamese students during first wave of the COVID-19 pandemic

This study aims to describe the COVID-19 related information searching behaviors and the relationship between those behaviors and the satisfaction with the COVID-19 related information searched on the Internet among university students during first wave of the COVID-19 pandemic in Vietnam