Phan Thiet Research Articles

Morpho-anatomical characteristics and antimicrobial activity of crude extract of Tephrosia villosa (L.) Pers. growing on sandy soil of Phan Thiet City, Binh Thuan Province, Vietnam

Tephrosia villosa (L.) Pers. is an herb species distributed mainly in arid sandy lands of the South Central Coast of Vietnam, including Binh Thuan province. The existing Vietnamese folk remedies have mentioned the medicinal effects of this herb in the treatment of edema and diabetes. Documents available in Vietnam provided only basic information on the morphology of this species. Therefore, this study aimed to investigate the morphological and anatomical characteristics of stems, leaves and roots of the plants in the analysis of relation to climatic conditions of the region. Antibacterial activity was initially studied as a basis for subsequent pharmacological studies. The crude ethanolic extracts were tested for inhibitory against Pseudomonas aeruginosa and Staphylococcus aureus by agar well diffusion method. The results showed that the plants had formed the morpho-anatomical characteristics to adapt to strong wind, strong light, high temperature, and dry sandy soils of the region. The ability to inhibit the two mentioned bacteria via the diameters of the halo was 10.8 – 12.7 mm, respectively. The recommendation was to continue to study the anatomical characteristics of the primary roots to complete the data and further investigate the antibacterial and antifungal activities of extracts of Tephrosia villosa.

Morpho-anatomical characteristics and antimicrobial activity of crude extract of Tephrosia villosa (L.) Pers. growing on sandy soil of Phan Thiet City, Binh Thuan Province, Vietnam

Morpho-anatomical characteristics and antimicrobial activity of crude extract of Tephrosia villosa (L.) Pers. growing on sandy soil of Phan Thiet City, Binh Thuan Province, Vietnam

Geotourism Potential Of Phu Quy Island, Binh Thuan Province

Phu Quy island – Binh Thuan province, is 120 km southeast of Phan Thiet city, where the long – lasting destruction of waves, wind, and rain into oceanic volcanic materials formed four significant geomorphological heritages. These geomorphosites have scientific and additional values (cultural, aesthetic, and ecological values), of which mountain Cao Cat cinder cones deserves to be a South Central Coast geomorphosite; while mountain Cam volcano, Hang Cliff – Nho beach erosion coast and Tranh volcanic islet are proposed at a local level. The impressive cliffs exposed layers of coarse and steeply sloping sediments caused by blasting; erosion coastal terrain such as cliffs, rocky headlands, stacks, arch, islets, etc. all shapes and colors associated with landmarks such as Mong Tay tack, Gam inlet, Ban inlet, Xuong Ca headland, Phat inlet, Dried Squid pond, Den islet, Giua islet, Do islet... are outstanding scientific values. Furthermore, Sa Huynh cultural relics (2,500 – 3,000 years ago) discovered in mountain Cao Cat; Linh Son, and Linh Buu ancient pagodas; Phu Quy landscape viewpoints from mountain Cam Lighthouse or colorful coral reefs on Tranh islet... are additional values that increase the worth of Phu Quy island's geomorphosites. Interpreting the scientific and additional values of these geomorphosite with images, books, geometrically similar models, etc. would promote the geotourism – a niche of the sustainable tourism market that is developed along with Global Geoparks recognized by UNESCO.

The effectiveness of Topic-Based Writing on EFL Learners’ Writing Skill

Being accepted as out of the four essential language skills in the language learning process, writing seems to be difficult for numerous EFL learners. This research is an endeavor to explore if learners can grow out of the writing difficulties with topic-based writing activity. 78 third-year students at the Faculty of Foreign Languages of Phan Thiet University in Phan Thiet City, Binh Thuan Province participated in the study. These students were in the two writing classes, one class was treated as the experimental group (EG) and the other as the control group (CG). Research findings exposed the benefits of topic-based writing activity in nurturing learners' writing motivation and enhancing their writing skill. Furthermore, this activity gave students good chances to widen their knowledge on the topic, enrich their emotion on disadvantaged people, and build a friendly learning environment outside the classroom. The necessity and usefulness of the application of topic-based writing activity was predominantly recognized among students.

Tertiary English-majored Students’ Perceptions toward the Role of Pronunciation in English Language Learning and their Practicing Strategies

Accurate pronunciation has a vital role in English language learning as it can help learners to avoid misunderstanding in communication. However, EFL learners in many contexts, especially at the University of Phan Thiet, still encounter many difficulties in pronouncing English correctly. Therefore, this study endeavors to explore English-majored students’ perceptions towards the role of pronunciation in English language learning and examine their pronunciation practicing strategies (PPS). It involved 155 English-majored students at the University of Phan Thiet who answered closed-ended questionnaires and 18 English-majored students who participated in semi-structured interviews. The findings revealed that students strongly believed in the important role of pronunciation in English language learning; however, they sometimes employed PPS for their pronunciation improvement. Furthermore, the results showed that participants tended to use naturalistic practicing strategies and formal practicing strategies with sounds, but they overlooked strategies such as asking for help and cooperating with peers. Such findings could contribute further to the understanding of how students perceive the role of pronunciation and their PPS use in the research’s context and other similar ones. Received 10th June 2019; Revised 12th March 2020; Accepted 12th April 2020

Do wooden pile breakwaters work for community-based coastal protection?

In developing countries, coastal protection with wooden piles may be a low-cost and eco-friendly countermeasure option that can be readily implemented by local communities or even individuals. However, the effectiveness of these piles in a realistic environment has yet to be scientifically proven, and there have been no established design guidelines for this type of improvised coastal protection to date. This study focuses on Phan Thiet City, Vietnam, where local people are resorting to wooden piles to mitigate severe coastal erosion immediately in front of their houses. A 3D hydrodynamic modelling with irregular waves is applied to evaluate complex wave mechanisms and hydrodynamics around and between wooden piles. The complicated interaction mechanisms between incident and reflected waves cannot be adequately evaluated using a common 2D numerical model or mathematical analysis, demonstrating the benefit of using a 3D hydrodynamic model. The performance of wooden piles are simply assessed using two criteria: wave run-up and bending stress. The result shows that wooden piles installed at a severely eroded beach in Vietnam can reduce wave run-up on the beach slope to some extent. The reduction in wave run-up occurs because of the creation of turbulence and oscillation triggered by the partial reflection of waves on the piles, diverting water flows into various directions. A case study shows that wave pressure in the seaward direction is about a half of that in the shoreward direction. However, the pressure in the negative direction can be instantaneously increased due to a significant reflection from a steep shore. This paper discusses whether such a state-of-the art computational fluid dynamics model can contribute to the assessment of wooden pile breakwaters.

Assessing the competitive advantages of tourism potentials in Tuy Hoa city, Phu Yen province

This paper presents a Quantified SWOT (Strengths, Weaknesses, Opportunities and Threats) analytical method and an analytical hierarchy process method which provides more detailed and quantified information on tourism potential in Tuy Hoa city. Quantified SWOT analysis was used to assess the competing strength of Tuy Hoa’s tourism potential with other places. The results of the study presented that Tuy Hoa city has many advantages of beautiful natural landscapes, nature, rivers and mountains. The results of the comparing value of internal and external factors of Tuy Hoa’s tourism potential indicated it under high competitive pressure from neighbor destinations such as Phan Thiet, Hue, Nha Trang and Da Nang. Tuy Hoa’s tourism potential was lower than that of neighbor cities but it has more attractive tourism features.

Additions to the Gobioidei Fauna of Nha Trang and Phan Thiet Bays (South China Sea, Vietnam)

Information is provided on new specimens of the recently described Amblyeleotris memnonia species (Gobiidae), previously known only by its holotype. The absence of sufficient grounds for changing the generic affiliation of Navigobius khanhoa (Microdesmidae) is shown. The ontogenetic variability of some features of Oxymetopon curticauda (Microdesmidae) was clarified.

A Multidisciplinary Approach for Evaluating Spatial and Temporal Variations in Water Quality

The primary goal of this study is to investigate the classification capability of several artificial intelligence techniques, including the decision tree (DT), multilayer perceptron (MLP) network, Naïve Bayes, radial basis function (RBF) network, and support vector machine (SVM) for evaluating spatial and temporal variations in water quality. The application case is the Song Quao-Ca Giang (SQ-CG) water system, a main domestic water supply source of the city of Phan Thiet in Binh Thuan province, Vietnam. To evaluate the water quality condition of the source, the government agency has initiated an extensive sampling project, collecting samples from 43 locations covering the SQ reservoir, the main canals, and the surrounding areas during 2015–2016. Different classifying models based on artificial intelligence techniques were developed to analyze the sampling data after the performances of the models were evaluated and compared using the confusion matrix, accuracy rate, and several error indexes. The results show that machine-learning techniques can be used to explicitly evaluate spatial and temporal variations in water quality.

Public perception of biofuel usage in Vietnam

ABSTRACTThis paper examines public perception of biofuels in southern Vietnam through a questionnaire survey administered to the general public in two cities in the country (Ho Chi Minh City and Phan Thiet) and experts in the field, in an attempt to understand the demand side motivations of biofuel usage. The survey enquired about the awareness of biofuel availability in Vietnam, motivations for using biofuel, and willingness to purchase biofuel. It was found that awareness was positively correlated with higher education levels, and that all groups were encouraged by the perceived environmental friendliness of biofuel. In terms of willingness to purchase, there was a clear difference in the perception of the appropriate pricing policy for biofuels between the public groups and the experts, with the former preferring higher prices and the latter lower prices. The study then concludes by discussing policy recommendations for improving consumer demand for biofuels in Vietnam and presents suggestions for future research, if the Vietnamese government decides that it is in its interest to pursue biofuels in the future.

Determination of Cobalt in Seawater Using Neutron Activation Analysis after Preconcentration by Adsorption ontoγ-MnO2Nanomaterial

Theγ-MnO2nanomaterial has been used to adsorb cobalt in the seawater at Phan Thiet City, Binh Thuan Province, Vietnam. Its concentration is determined by using the neutron activation analysis (NAA) method at the Dalat nuclear research reactor. Factors affecting the uptake of cobalt on theγ-MnO2material such as the pH, adsorption time, and initial cobalt(II) concentration are investigated. The irradiated experiment data are calculated using the K0-Dalat program. The results obtained show that the trace dissolved cobalt in Phan Thiet seawater is found equal to 0.25 ± 0.04 μg/L (n=5,P=95%) with the adsorption efficiency being higher than 95% (n=4,P=95%).

Simon Creak. Embodied Nation: Sport, Masculinity, and the Making of Modern Laos

Embodied Nation: Sport, Masculinity, and the Making of Modern Laos Simon Creak Honolulu: University of Hawai'i Press, 2015, xvi+337p.This book is a welcome addition to the literature on under-studied country, Laos, on also under-studied topic, sport in relation to nationalism and masculinity.Before looking at the evolution of sport and masculinity from a chronological perspective, Simon Creak reviews in the Introduction numerous theories and concepts related to physicality and masculinity-from Ana Maria Alonso's idea that physical practice strengthens national consciousness to Clifford Geertz's view of power in a theatre state exercised through spectacle, for instance-as a to present his overall argument that sport is the most significant means of substantializing notions of the body, masculinity, and the in modern societies (p. 12), since at the center of the book is empire building, making, and socialist construction.The first chapter discusses the case study of the indigenous game tikki, which resembles field hockey, and how French travelers' accounts transformed the game into a crucial element of what it meant to be truly Lao. Such accounts served the French colonial state's aim to differentiate the Lao territories and people from Siam and the Siamese. Indeed, the traveler-writers, young Lao researchers, and Ecole francaise d'Extreme-Orient scholars Paul Levy and Charles Archiambault, by writing about tikki a tradition and ritual, helped in creating an idea of Laos, justifying its constitution a French colony and later a distinct and independent nation (p. 50).Advancing through the French colonial period, chapter 2 presents the Vichy-era Lao Nhay cultural renovation movement (1941-45). While reading this chapter discovered that it was built a critique of my own work on the Lao Nhay movement and sports in Laos during the Vichy era (Raffin, 2005). The author contests my argument that sport development was secondary to the promotion of the Lao Nhay movement, whose function was to nurture a cultural and linguistic nationalism in response to the threat of Thai irredentism in Laos. Creak contends that both were important and complemented one another (p. 53). Although rightfully underlining that did not look at Lao-language sources, his own argument is based mostly on French sources. Adding a few examples from Lao-language sources on sport, a Lao-language novel by P. S. Nginn (who was a Lao Nhay member), a short excerpt of the memoir of Governor Jean Decoux stating that I decided to rely on Sports-Youth activities in this country to launch 'le movement lao' (p. 66), and mentioning the creation of sport clubs without talking about their activities, membership, etc. does not provide enough evidence to convince me that the colonial state's politics at the time promoted both sport and the Lao Nhay movement on equal footing and that subsequently the Lao Nhay movement was as much a physical awakening it was a mental or cultural one in Laos, too (p. 64).Overall, through this chapter the author stresses how the male body was the primary agent of Philippe Petain's National Revolution in the metropole and in Indochina, and how racial and right-wing ideologies well militarism shaped sport policies in Indochina. Such a militarization of society was carried out in the 1950s, with the National Youth and Physical Education Cadre School, or ENCJEP, being molded after the Vichy-era schools in Phan Thiet and Vientiane (p. 95).This leads to chapter 3, which discusses the militarization of masculinity in independent Laos during the 1950s. Projects are usually not carried out in a vacuum; hence, the sport policies of the 1950s show quite a few continuities with the World War II period, from the military-style choreography of human bodies to adapted Vichy-era uniforms for ENCJEP instructors and trainees and the use of the natural method for trainee parachutists. …

ENSO and anthropogenic impacts on phytoplankton diversity in tropical coastal waters

16-year phytoplankton data were analysed to assess ENSO and anthropogenic impacts on biodiversity and community structure at 3 locations (Nha-Trang and Phan-Thiet Bays and near Phu-Qui Island) in South Centre Viet Nam to understand (1) the primary scales of change in phytoplankton community structure, and traditional and taxonomic diversity indices; (2) the significance of environmental changes and/or climate variability on phytoplankton diversity; and (3) the usefulness of these long-term data for analysing future impacts of anthropogenic and climate changes. Traditional and taxonomic diversity indices were compared and tested in linkage with environmental conditions and ENSO. Nutrient data indicated stronger environmental impacts in Phan-Thiet Bay, milder in Nha-Trang Bay and less noticeable near Phu-Qui Island. There were measurable impacts of both anthropogenic and ENSO on phytoplankton at different locations in various parameters, e.g. species number, diversity and community structures. The lowest diversity was recorded in the most anthropogenically impacted site, Phan-Thiet Bay. Although a stronger impact on phytoplankton was recorded in ENSO year in Phan Thiet Bay, quantitative separation between anthropogenic and ENSO impacts using phytoplankton biodiversity indices was impossible. In the waters with less anthropogenic impacts, ENSO effects on taxonomic diversity was better indicated by negative phytoplankton responses to the ONI index (Nha-Trang Bay) and recovery of phytoplankton after the ENSO events (near Phu-Qui Island). Among the diversity indices, the taxonomic diversity indices (e.g. Δ+ and Λ+) better described impacts of ENSO than the traditional ones.

NGHIÊN CỨU CHẾ ĐỘ DÒNG CHẢY TẠI VỊNH PHAN THIẾT BẰNG MÔ HÌNH BA CHIỀU PHI TUYẾN VỚI PHƯƠNG PHÁP PHẦN TỬ HỮU HẠN

Different types of currents (residual-, tidal-, wind- and general currents, etc.) in Phan Thiet bay have been studied using 3D nonlinear finite element method (FEM). The studied results showed the applicability of FEM for simulation of current regime in waters with complex topography and large liquid boundary. To evaluate the applicability of the model, we calculated separately the 5 main current constituents M2, S2, K1, O1, N2 of tidal currents. Then the harmonic constants of these current constituents were compared with data collected from Phan Thiet water level station. According to the comparison results, the absolute differences are as follows: the amplitude was max 3.1 cm (constituent M2), min 0.0 cm (exact constituent S­2), the tidal phase was max 13.90(constituent K1) and min 3.80 (constituent S2). In the surface layer, during northeast monsoon period, the horizontal wind currents may reach its max speed of 85.3cm/s, direction 185.70 around the position (108.05540E; 10.70140N); but the peak horizontal speed of the general currents can reach 60.6cm/s, direction 209.60, around position (108.08200E; 10.70150N). During southwest monsoon period, max speed of the horizontal wind currents reaches 53.0cm/s, direction 10.30; position (108.1086E; 10.70150N), whereas, general current was 36.6cm/s, direction 23.80; position (108.03550E; 10.70540N). These study results are the first 3D nonlinear calculation results for the currents in Phan Thiet bay. These results have shown the possibility of detailed study of current distribution and finding out positions with particular current distribution in this area, providing scientific base and reliable information for a reasonable development planning.

TÍNH TOÁN THỬ NGHIỆM LAN TRUYỀN VẬT CHẤT CHO VỊNH PHAN THIẾT (BÌNH THUẬN)

Từ kết quả nghiên cứu của đề tài cấp Nhà nước KC.09.24/06 -10, chúng tôi giới thiệu một số kết quả tính toán thử nghiệm từ chương trình “Phan Thiet ver 1.0”. Trong chương trình tính toán cấu trúc dòng chảy (dòng triều và dòng dư được xét đến) bằng mô hình thủy động lực ba chiều phi tuyến được giải bằng phương pháp phần tử hữu hạn, Mô hình phân tán dựa trên kỹ thuật theo dõi dấu vết chuyển động của các hạt (particles-tracking), được phân tích một cách độc lập. Các quá trình lan truyền và phân tán các chất gây ô nhiễm có thể được mô phỏng (với các đặc điểm về lý-hóa có được từ thực nghiệm) theo phương pháp ngẫu nhiên - phương pháp Monte Carlo. Các hạt chất điểm (5.000 chất điểm) không biến đổi và tương tác sinh - lý – hóa trong quá trình chuyển động dưới tác động của triều kết hợp với hai chế độ gió mùa Đông Bắc và Tây Nam. Các tính toán ban đầu tập trung ở lớp nước bề mặt (từ 0-30m). Trong tương lai chương trình sẽ phát triển theo hướng có thể mô phỏng tốt hơn (các hạt vật chất sẽ thực hơn) các hiện tượng có ảnh hưởng và tác động tới môi trường như rác thải trôi dạt, phân tán các vật liệu, chất gây ô nhiễm, lan truyền màng dầu, … Summary: Based on the research results of National project KC09-24/06-10, in this paper we would like to present our experimental calculation results - a program called Phan Thiet Ver. 1.0 - obtained from a physical model with simplified conditions to calculate and predict material (particles) transport in Phan Thiet bay. In the our first version process of particules transport is simulated in the good mixing layer from 30 meters depth to the surface. Our computed model includes two parts: + Dynamical model: The 3D nonlinear model was solved by finite element method, simulating the resultant current (tidal currents, residual current) during the two main south-west and north-east monsoons. + Transport model: Monte Carlo (incidental) method was used for calculation of about 5,000 elements located at arbitrary positions (particles-tracking), in the study area. We did not include the biological, physical, chemical and interaction processes into the calculation of the movement of the elements. The initial computed results allow us to identify the places where environmental hazards may occur, and its development and occurrence time as well.

Two new species of fishes from families Muraenidae (Anguilliformes) and Mugiloididae (Perciformes) from the Waters of Vietnam

New species of the genera Gymnothorax (fam. Muraenidae) and Parapercis (fam. Mugiloididae) are described from coastal waters of central Vietnam. G. emmae sp. n. is a common species all along the coast from the Van Phong Bay to the Phan Thiet Bay and differs from other species of this genus in characters of coloration, dentition, and the vertebral formula. P. bicoloripes sp. n. is common in the Phan Thiet Bay and is also know from one specimen from the Nha Trang Bay; from other species of the genus, it differs in coloration and meristic characters.

Dengue Dynamics in Binh Thuan Province, Southern Vietnam: Periodicity, Synchronicity and Climate Variability

BackgroundDengue is a major global public health problem with increasing incidence and geographic spread. The epidemiology is complex with long inter-epidemic intervals and endemic with seasonal fluctuations. This study was initiated to investigate dengue transmission dynamics in Binh Thuan province, southern Vietnam.MethodologyWavelet analyses were performed on time series of monthly notified dengue cases from January 1994 to June 2009 (i) to detect and quantify dengue periodicity, (ii) to describe synchrony patterns in both time and space, (iii) to investigate the spatio-temporal waves and (iv) to associate the relationship between dengue incidence and El Niño-Southern Oscillation (ENSO) indices in Binh Thuan province, southern Vietnam.Principal FindingsWe demonstrate a continuous annual mode of oscillation and a multi-annual cycle of around 2–3-years was solely observed from 1996–2001. Synchrony in time and between districts was detected for both the annual and 2–3-year cycle. Phase differences used to describe the spatio-temporal patterns suggested that the seasonal wave of infection was either synchronous among all districts or moving away from Phan Thiet district. The 2–3-year periodic wave was moving towards, rather than away from Phan Thiet district. A strong non-stationary association between ENSO indices and climate variables with dengue incidence in the 2–3-year periodic band was found.ConclusionsA multi-annual mode of oscillation was observed and these 2–3-year waves of infection probably started outside Binh Thuan province. Associations with climatic variables were observed with dengue incidence. Here, we have provided insight in dengue population transmission dynamics over the past 14.5 years. Further studies on an extensive time series dataset are needed to test the hypothesis that epidemics emanate from larger cities in southern Vietnam.

EXTRACTING THE WATERLINE FROM LANDSAT IMAGES

Remote sensing technology nowadays is one of the most useful tools for scientific research in general and for oceanography in particular. From satellite images, the useful information such as waterline images can be extracte for a large region simultaneously. After tidal adjustments, the waterlines can be used as the observed shorelines which are important inputs for estimating shoreline changes by either using the integration of remote sensing and GIS or using numerical models. Based on the spectral bands of various Landsat images, the paper presents the methods to detect the waterlines in Phan Thiet region in the 40 years period using the images of 1973, 1976, 1990, and 2002 respectively. The extracted results relatively agree with the information of waterline from the images.

Rural Labour Distribution in a Dynamic Agricultural Region: The case of Phan Thiet, Vietnam

ABSTRACTThis article presents a case study challenging the dominant view that diversification out of agriculture brings higher household incomes in rural areas. In the area around Phan Thiet City in Vietnam, daily wages for casual agricultural labour are comparable to those for unqualified non-agricultural labour; in some cases, the former can even be higher. These facts can be explained by the dynamism of the agricultural sector in the area, the small size of household plots, the importance of cash crops in the production system, the adequacy of access to markets and the general use of cash for all transactions.

Thermoluminescence ages for a reworked coastal barrier, southeastern Vietnam: a preliminary report

Thermoluminescence dating of quartz sand (90–125μm) from the coastal barrier successions between Phan Thiet and Tuy Phong, southeastern Vietnam, reveals that a substantial component was deposited during the last interglacial sensu lato (Oxygen Isotope Stage 5) between 108 and 85ka. The barrier successions have subsequently, in places, experienced multiple phases of aeolian reworking during the last glacial cycle, and in particular between 62 and 19ka, possibly related to reduced vegetation cover and landscape instability caused by climatic change. The difficulties of applying the thermoluminescence (TL) method in areas of intense tropical weathering are also examined.