Southern Part Of Vietnam Research Articles

A new species of the genus Rambutanura Deharveng, 1988 from southern Vietnam (Collembola, Neanuridae)

Rambutanura oblita sp. nov. from the southern part of Vietnam is described and illustrated. It differs from all previously known species of the genus by the presence of only seven tubercles on the head (tubercle Cl undeveloped, vs present in all other known congeners), and of elongated digitate tubercles only on three last abdominal segments. In all other species such prolonged, finger-like tubercles are either present also on the head and thorax or completely undeveloped.

The effect of innovation on competitive advantage and SMEs performance in Vietnam: the moderating role of customer orientation

Purpose The purpose of this paper is to find out how absorptive capacity (AC), leadership capacity (LC) and government support (GS) affect small and medium enterprises (SMEs) innovation (product innovation [PDI], process innovation [PCI] and distribution channel innovation [DCI]), taking into consideration the role of innovation (PDI, PCI and DCI) on competitive advantage and SMEs performance and the moderating role of customer orientation (CO). Design/methodology/approach This study gives a theoretical model tested using structural equation modeling. The information used to test the hypotheses came from interviews with the top managers of Vietnam’s SMEs. The 633 survey respondents from the southern part of Vietnam were chosen for the study. The goal of the 47-item questionnaire is to look at how all variables relate to each other. Findings The results show that a firm’s LC has the most significant impact on innovation, followed by its AC and GS. According to the study, DCI does not lead to competitive advantage but improves SMEs’ performance. In addition, the study’s findings indicate that CO moderates the relationship between PDI – SMEs performance and DCI – SMEs performance. Research limitations/implications The classification of only three types of innovation (PDI, PCI and DCI) restricted the applicability of the research to other kinds of innovation in SMEs. Second, only AC, LC and GS are identified in this study as external factors that influence business innovation. In this study, the authors have not studied different business industries; the authors recommend that the research in the back on SMEs should investigate their classification into distinct industry groups, including agricultural, forestry and marine products; industry and construction; and commerce and services. Practical implications This study shows the importance of innovation senior management for innovation in SMEs. This study found that innovation, especially continuous innovation, increased competitive advantage and SMEs performance. Companies that wish to innovate must have access to external resources and support. Moreover, enterprises must comprehend their consumers’ wants to achieve innovation and better SMEs’ performance. Social implications This research significantly contributes to enterprise innovation and operational efficiency for the sustainable development of SMEs in Vietnam. It is expected to enhance employment opportunities, maintain social stability and expand Vietnam’s gross domestic product. Originality/value This study contributes to the growing knowledge of the indirect and direct effects, the mediating function of innovation (PDI, PCI and DCI) on competitive advantage and SMEs performance and the moderating effect of CO.

Reconsideration of importance of the point mutation L982W in the voltage-sensitive sodium channel of the pyrethroid resistant Aedes aegypti (L.)(Diptera: Culicidae) in Vietnam.

Pyrethroid resistance in Aedes aegypti is widespread in southern Vietnam because the photostable 2nd generation pyrethroids have been used in large amounts over extensive areas for malaria and dengue vector control. In our previous report in 2009, F1534C, one of the point mutations in the voltage-sensitive sodium channel (VSSC) in Ae. aegypti, was widespread at high frequency in south and central area. However, no significant correlation between the frequency of F1534C and pyrethroid susceptibility was detected primarily because the F1534C mutation frequency in the southern highland area was very low, despite that the bioassay indicated high pyrethroid resistance. The point mutation in the VSSC, L982W, which was not the target mutation in our previous study, was recently determined to be an important mutation causing high-pyrethroid resistance in Vietnamese Ae. aegypti. In the present study, a re-investigation of L982W in the mosquito samples collected in 2006-2008 revealed a greater distribution of this mutation (allelic percentage 59.2%) than F1534C (21.7%) and the greater proportion of homozygous L982W as compared to F1534C provided a plausible answer to the question concerning the unknown resistance factor in the southern highland area. L982W frequencies were uniformly higher in the southern part of Vietnam, including the highland area with a significantly high positive correlation with pyrethroid resistance in Ae. aegypti.

Models for biomass expansion factor of acacia hybrid (A. auriculiformis* A. mangium) plantations in the Southern region, Vietnam

Acacia hybrid is one of the favorably fast-growing species which is bring to potential benefits of agro-ecological and socio-economic sectors in Vietnam. The main objective of this study was to develop well-fitted models for estimating biomass expansion factor (BEF) for Acacia hybrid plantations. Fifty-four samples of Acacia hybrid trees from 2 to 10 years of age were collected from Acacia hybrid plantations in the Southern part of Vietnam. Total dry biomass including stems, branches and leaves were used to estimate an average value of BEF. The BEF value was calculated by taking the dry aboveground biomass (W) divided by the volume of merchantable tree woods over their barks (Vm). Twelve allometric equations were fitted by constructing regression models between BEF and inventory variables including diameter at breast height (DBH), height (H) and age (A). Consequently, the average value of BEF was 1.11 ton/m3. The BEF value had a strongly negative relationship with DBH, height and age in which the BEF value decreased as these three parameters increased. Two best fitted models for estimating a BEF value of Acacia hybrid (A. auriculiformis * A. mangium) plantations included: BEF = 1.99865 - 0.15400*DBH - 0.02123*H + 0.18210*A; and BEF = 3.01307 - 2.44459*ln(DBH) - 0.10171*DBH -2.06212*ln(H) + 1.54556*ln(DBH*H*A). Estimated values of above-ground biomass by utilizing the fitted BEF values from two these models were similar. Results of the study indicated that use of a fitted BEF model is fundamental to obtain reliable estimates of biomass and CO2 equivalent for Acacia hybrid plantations.

Machine learning models for estimating preliminary factory construction cost: case study in Southern Vietnam

Construction of industrial enterprises has become more necessary in recent years. It is critical for project managers to estimate the entire cost of a building project at this early stage. Existing approaches that use operator experience as a mathematical formula. Initial estimates are inaccurate due to the lack of available data points, which leads to overruns in project costs. This research utilizes different machine learning techniques to predict preliminary factory construction cost. Five popular numeric predictive techniques: support vector machine (SVM), artificial neural network (ANN), generalized linear regression (GENLIN), classification and regression-based techniques (CART), exhaustive chi-squared automatic interaction detection (CHAID) are used for baseline and ensemble models. A deep learning neural network (DLNN) is also utilized in this study. The machine learning model is trained and tested on actual data gathered in the southern part of Vietnam. Deep learning outperforms all other machine learning algorithms in this comparison, while the ensemble model of artificial neural networks and generalised linear regression also fared well. Cost estimators can quickly pick the best model for projecting the cost of constructing a preliminary factory by having access to a variety of estimate methodologies.

Seismic activity in the continental shelf of South-Central Vietnam and adjacent regions from 2005 to 2020

Since 2005, 10 seismic monitoring stations have been installed in the southern part of Vietnam. These stations can detail the earthquakes in the region and adjacent areas. In the past, there was an earthquake of magnitude 6.1 (1923) in the offshore South-Central Part related to the Hon Tro eruption, the largest observed earthquake magnitude in the 20th century. Between 2005 and 2020, 371 earthquakes were recorded with magnitudes ranging from 0.7 to 5.3. Most of events were distributed on some northeast-southwest direction faults in South Central offshore. The magnitude of the representative earthquake was relatively small, Mc = 2.2, so it is assumed that this research area was of weak activity. The epicenter is about < 20 km, and the majority concentration is at a relatively shallow depth of 5km and still located in the crust of Earth. The relationship between earthquake magnitude and frequency in this region is as follows: lgN = 4.063 – 0.694*M for the entire catalog of 371 events and lgN = 3.826 – 0.704*M after filtering 92 foreshocks and aftershocks of the earthquakes M = 5.3 on November 8th, 2005, and M = 5.2 on November 28th, 2007. So, the calculated average b-values before and after filtering foreshocks and aftershocks were approximately 0.7. These values are almost approximate to the b-value of 0.76 determined by Pham Van Thuc et al., (2004) based on the East Vietnam Sea earthquake catalog from 1903 to 2002 and smaller than the b-value of 0.92 for triggered earthquakes in the Song Tranh 2 hydropower region. In addition, oil and gas exploitation activities are still taking place in the South-Central continental shelf; it is necessary to continue collecting earthquake data to elucidate the causes of earthquakes in the study region.

VIETNAMESE LEARNERS’ ATTITUDES TOWARDS AMERICAN AND BRITISH ACCENTS

English possesses different varieties due to its worldwide usage which challenges the tendency of favorite accents among EFL classrooms in non-English speaking countries. However, learners show more positive familiarity and preference for General American English (GA) and British English, Received Pronunciation (RP) which are grouped as the inner-circle of English. This study investigated 53 students in a university in southern part of Vietnam. They were asked to complete an online questionnaire which examined their evaluations of two accents on different traits of status and solidarity, their preference and familiarity. A verbal guise technique is employed with two female native speakers. The data was analyzed by SPSS with different T-tests and ANOVA. The study revealed that the respondents showed greater recognition and evaluations for GA which associated with prestige, familiarity and social attractiveness. Nearly two-thirds of participants revealed a preference to the American speaker although more than half of them did not recognize where she was from.

Temporal patterns and space-time cluster analysis of foot-and-mouth disease (FMD) cases from 2007 to 2017 in Vietnam.

In Vietnam, Foot‐and‐mouth disease (FMD) is endemic, but no nationwide studies have been conducted to assess the monthly variations and space‐time clusters of FMD. The main objective was to identify the temporal patterns and space‐time clusters of FMD from 2007 to 2017 using national surveillance data in Vietnam. A total of 163,733 cases were reported from 2007 to 2017. Among them, the proportion of buffaloes (43.31% of total reported cases; 70,909 cases) was highest followed by cattle (30.11%; 49,306 cases), pigs (26.67%; 43,662 cases) and sheep/goats (0.41%; 675 cases). The serotype O was widely distributed across the country while serotype A was observed in Northeast, Central and Southern part of Vietnam while Asia 1 has been not identified since 2007. For monthly variations, most cases were observed during the dry season (from November to March) except Central Highlands. Under the spatial window was set at 50%, a total of seven clusters were identified. The primary cluster was observed from Dec 2009 to Dec 2010 in the northwest (radius: 101.67 km), showing a ratio of 3.75. The secondary cluster was detected in the northeast region (radius: 76.54 km) with a ratio of 3.53 in Feb 2017. The 3rd cluster was the largest with a radius of 176.69 km and located in the southern part of Vietnam. Interestingly, the most temporal clusters included between December and March during the study period. Our findings provide better insight into the temporal patterns and distribution of clusters of FMD in Vietnam. This study provides useful information to policymakers on the hotspot areas and timing of outbreaks. It also identifies when and where national surveillance and control programmes could be implemented more efficiently for the prevention and control of FMD.

1978년 난교(難僑)송환선 사건을 통해 본 중국과 베트남난민

The paper examines the affair of Vietnam Huaqiao repatriation ship in the spring and summer of 1978, and the controversies and conflicts over the Huaqiao in Vietnam including citizenship problem between China and Vietnam. It also sheds new light on the attitudes and policies of China on the Vietnamese refugees by clarifying the relationship between the affair of Vietnam Huaqiao repatriation ship and the large-scale eruption of the Vietnamese boat people. This study above all things focuses on the terminology, the issues raised, the reasoning and the silence expressed in the Peoples Daily (人民日報, Renmin Ribao), an official newspaper of the Central Committee of the Communist Party of China, on Vietnamese refugees for 20 years from 1975 to 1995. The affair of Vietnam Huaqiao passenger ships is not only worthy of reexamination itself, but also is of importance in the understanding of the conflict and war between China and Vietnam in 1978 and 1979. Due to its involvement in the Vietnam Huaqiao problem, China has become the largest Vietnamese refugee settlement nation in Asia and the next largest after the U. S. in the world. In addition, in early 1979 China launched an offensive in response to Vietnams allegedly anti-Chinese and anti-Overseas Chinese activities and attitude. At the same time, Vietnamese refugees erupted, which has been known as ‘Boat People Crisis.’With the incident, China became part of the international humanitarian order. In this article, we will identify how all these events are linked together and influenced by the affair of Vietnam Huaqiao repatriation ships. The combination of the three factors of 1978 and 1979, such as the pulling effort of China towards the overseas Chinese which was strongly exemplified in the affair of the Huaqiao repatriation ships, the release of the overseas Chinese by Vietnam and the intervention of international humanitarianism, led to the exodus of the overseas Chinese people from the southern part of Vietnam. In addition, as Vietnams relatives network of Vietnamese refugees who had left immediately before the fall of Saigon in April 1975, and the network of Southeast Asian Chinese overseas converged, the number of boat people rapidly increased, and the boat people crisis was created in the process. Finally, this paper is intended to reveal the causal link between the state involvement and the sudden increase in the number of boat people, so that the intentional involvement of the state on the foreign policy side can bring unexpected and expensive costs to refugee themselves.

The Binh Chau Hot Spring Resort

Binh Chau Hot Spring is the only hot spring source available in the southern part of Vietnam, located approximately 125km away from Ho Chi Minh City. The hot spring was found in early 20th century by a French scientist and the Saigon Binh Chau Corporation has been developing the hot spring to the public for more than a decade now. In 2017, the number of visitors reached over 300,000 per year and in light with the increasing demand for wellness tourim, the corporation decided to substantially invest in a new development plan. Binh Chau Hot Spring aims to offer to its visitors a holistic experience of hydrotherapy within a preserved environment. The new Binh Chau Hot Spring will highlight its fantastic location between the sea and the forest and create a full range of activities around the hot spring and nature in general. Such activities will include a hot spring theme park, an ecological park (bamboo reserve, botanical garden...) and a 4-star international hotel. As far as hydrotherapy treatments are concerned, Binh Chau Hot Spring will provide both traditional and modern medicine. While the hot spring theme park will largely take its inspiration from the Japanese onsen, the treatments provided to the visitors will include a wide range of thalassotherapy techniques often used in Western countries and also traditional Vietnamese techniques (cupping, acupuncture...) that are well known among the Vietnamese public. Thanks to this unique positioning, Binh Chau Hot Spring aims at promoting the vertues of the hot spring and hydrotherapy to domestic and international visitors and consequently to become a major tourism attraction in the province of Ba Ria Vung Tau. In conclusion, it is a great honor and a high responsibility for Binh Chau Hot Spring to represent Vietnam and showcase our savoir faire to the world but we are deeply convinced of our mission and will devote all our best efforts in promoting FEMTEC and the benefits of hydrotherapy worldwide.

Notes on the butterflies of Thailand and southern part of Vietnam

Notes on the butterflies of Thailand and southern part of Vietnam

Dioxin contamination of bird eggs from different Vietnam provinces

This paper studies contamination by polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzo furans (PCDFs) of eggs of poultry and wild birds (chicken, duck, Streakeared Bulbul (Pycnonotus blanfordi), and Whiterumped Munia (Lonchura striata)) from ten provinces in the north and south of Vietnam. The concentrations of PCDDs/PCDFs had values from 0.4 to 107.6 pg WHOTEQ2005/g lipid and in the eggs of birds from the southern part of Vietnam they mostly exceeded concentrations in the eggs from the northern part.

HYDROGEOPHYSICS TECHNIQUES TO AQUIFER LOCATING AND MONITORING FOR INDUSTRIAL ZONE NORTH THANGLONG AND QUANGMINH, HANOI

HYDROGEOPHYSICS TECHNIQUES TO AQUIFER LOCATING AND MONITORING FOR INDUSTRIAL ZONE NORTH THANGLONG AND QUANGMINH, HANOI

One new genus and one new species of freshwater crabs (Decapoda, Brachyura, Potamidae) from the Southern part of Vietnam

Dalatomon gen. nov. Dang et Ho Diagnosis: crab is small in size, the length (l) under 30 mm, carapace trapezoid form, flat, upper surface smooth. Ischium maxilliped rectangular, merus almost rectangular, exopod long, reaching to 1/3 merus external margin. Male terminal segment of abdomen equilateral triangular, low with round top, lateral border straight, moderately longer than VI segment. GO1 terminal segment in male with dorsal, broad semicircular fold, extending to 2/3 length of this segment. Etymology: this genus name is derived from its type locality at Dalat (Lamdong province, west highland of Vietnam), in combination with the genus name Potamon. The gender is neuter. Type species: Dalatomon soni sp. nov. Dalatomon soni sp. nov. Dang et Ho Holotype: 1 male; Allotype, 1 female, collected from the stream at Dalat city (Lamdong province), Vietnam. Coll. 3 July, 2005; Paratype: 2 males, collected from Dalat city (Lamdong province). Coll 3 July, 2005, deposited in the Zoological Museum, Institute of Ecology and Biological resources, Hanoi-Vietnam. Diagnosis: crab is small in size, carapace largely transverse trapezoid, flat, upper surface smooth. Epibranchial tooth small. Anterolateral tooth not developed. Frontal margin moderately concave, Antero-lateral angle rounded, lateral margin oblique. Postfrontal, postorbital cristae cleared, undulated down, reaching to the basis of the epibranchian tooth. Postfrontal and postorbital bilobed swollen. Semilunar, H-shaped grooves distinct. Ischium maxilliped rectangular with groove in middle, exopod straigth, reaching to 1/3 merus external margin. Merus rectangular, flagella long reaching over merus upper margin. Male terminal segment of abdomen equilateral triangular, low with round top, lateral border straight, longer than VI segment. Subterminal segment of GO1 in male with basal part narrowly elongated. Terminal segment with dorsal, broad semicircular fold, located in the first half part, extending to 2/3 of this segment. Distal part of terminal segment cylinder-shaped, curved down tip truncate with upper distal angle produced as sharp, small, transparent projection. G2 long, slender, distal segment shorter than basal segment. Ambulatory legs slender, long. Remarks: Dalatomon soni sp. nov. is firstly found in Dalat city (Lamdong province), southern Vietnam. This species distributed in streams of highland mountainous areas but with small quantities. This new species is closely related to others species belonging to genera Laevimon, Donopotamon, Thaipotamon, Pudaengon, Rathbulamon, Phaibulamon, Pilosamon that are found in the Catba island (northern Vietnam) and in the basin of the Mekong river of southern Vietnam, Laos and Thailand. These species has the same characteristics such as terminal segment in GO1 of male with dorsal, broad semicircular fold but this new species differs from others by small size of carapace, the location of semicircular fold, the form of distal part of terminal segment and several different features as well. Table 1 Comparison of principal characteristics of Dalatomon gen. nov. with Donopotamon Dang et Ho 2005 and Laevimon Yeo et Ng., 2005 Characteristics of male Dalatomon Donopotamon Laevimon Size of carapace Small, the length less than 30 mm Big, the length more than 40 mm, even to 70 mm. Big, the length more than 40 mm. Carapace form Largely transverse trapezoid, flat, upper surface smooth. Largely transverse trapezoid, flat, upper surface smooth Anterolateral region rugose and granulose. Carapace distinctly transverse, high; dorsal surface strong convex longitudinally and transversely; smooth. Postorbital cristae Not sharp moderately oblique. Slightly sharp, horizontally straight. Uncleared. GO1 Subterminal segment with basal elongated. Terminal segment long 1/2 times length of subterminal segment, distal part curved down. Terminal segent with dorsal, broad semicircular fold, located in the first half part, extending to 2/3 of this segment. Terminal segment cylinder-shaped, tip truncate with upper distal angle produced as sharp, small, transparent projection. Subterminal segment with basal large, distal part narrow, neck-like. Terminal segment with dorsal, broad semicircular fold, occupying almost completely half distal part of this segment, establishing dove-head in shape. Subterminal segment with basal slender. Terminal segment short, about 1/3 times of subterminal segment. Terminal segment subcylindrical; tip truncate with inner distal angle produced as sharp, narrow projection. Hump-like, in proximal part, distinctly shorter than half length of terminal segment. Third maxilliped Ischium and merus rectangualar; exopod straight, reaching to 1/3 merus external margin. Flagellum long, reaching over merus upper margin; but shorter than merus width. Ischium rectangular; merus squarish; exopod straight, reaching to 1/3 merus external margin. Flagellum long, reaching over merus upper margin. Ischium broadly rectangular; merus squarish; upper angles rounded. Flagellum long, subequal to merus width. VII segment of the abdomen Equilateral triangular, low with round top, lateral border straight. Triangular; lateral border concave. Narrowly triangular; lateral border cocave at middle.

Current Status of the Occurrence and Farmer Perceptions of Rice Planthopper in Cambodia

This study aims to clarify the current status of rice plant damage caused by the brown planthopper (BPH) in Cambodia through semi-structured interviews with government officials and rice farmers from the main rice-producing province. BPH is known to cause serious damage to rice crops in many Southeast Asian countries. However, few studies exist on the damage caused by BPH in Cambodia and information on effective pest-control management remains limited. Interviews with provincial government officials revealed that BPH infestation had been recorded in 6 of 8 target provinces located near the border with the southern part of Vietnam. Of these, Takeo province was selected for a more detailed survey using semi-structured interviews with district government officials and workshop-style interviews with 416 farmers from 3 communes. These interviews indicated that damage by BPH in Cambodia was possibly attributable to BPH occurrence in the Mekong Delta of Vietnam.

Identification of colonial economic heritage in the southern part of Vietnam

As the first mass of land in Vietnam becoming a French colony, Nam Ky – the Southern part of Vietnam (currently renamed Nam Bo – the South of Vietnam) was affected, earliest and hardest, by the consequences of colonialism. Brutal governance mechanism; plundering ruses to fully exploit profit; policies of enslavement, for obscurantism, and cultural intoxication; etc. are all sinful acts and evil nature of colonialism which the Vietnamese people as well as the entire advanced humankind have fought against and eradicated. However, it would be full of prejudices, non-objective and one-sided to totally deny important impacts for the evolutional process of the nation’s history in a number of economic sectors that the colonial exploitation has brought, if temporarily excluding its driving force and purpose. Therefore, study of the process, characteristics and consequences of the policy to exploit colonies in the Southern part of Vietnam is to contribute to sound recognition of historical heritages during colonial times, also to better understand our socio-economic starting point 100 years, more or less, ago; so as to reach proper selection and inheritance in the mission of fostering industrialization and modernization for and towards today’s sustainable development strategy.

The process of community construction and organization, and social management in southern Vietnam: advantages and challenges in integration context

Southern region of Vietnam is located in the crossroad of different cultures. Historical and ethnic process as well as cultural acculturation is diverse, multifaceted and complicated due to the presence of many ethnic groups in the area. Diversity in ethnic structure leads to cultural diversity which reflects all aspects of life such as economy and socio-culture of the peoples. Community construction and organization and social management in southern Vietnam go hand in hand with the process of land reclaimation, settlement establishment, and sovereignty claiming, expanding and practicing. Although the ethnic peoples migrated to the region at different times, they all equally contributed to the exploration and development of this highly potential region and to the constitution of “Van Minh Miet Vuon” – literally, the civilization of orchard regions. However, each ethnic group obviously has their own cultural traditions which, when combined together, create a mosaic culture of the whole region. Despite commonality in the process of community construction and organization and social management, distinctiveness of each group still exists. Contemporarily, when integration and development are considered both common aims and motivations, advantages of each cultural tradition should be explored while its limitations, at the same time, should be identified in order to overcome disadvantages for good. As a result, scientific conceptualization about the process of construction and development of the region obviously contributes to maintaining and reinforcing ethnic solidarity for the cause of national building and developing. This paper, based on research outcomes of previous studies and field data in southern region in recent years, presents the process of community construction and organization and social management, both historically and contemporarily. Also, the author aims at identifying advantages and challenges of traditional culture (in this case, traditional social structure) in the current integration process in the southern part of Vietnam.

Southern of Vietnam in the context of international integration era

The Southern part of the country is located directly in the Mekong sub-region with 3-side sea-contact. The location of the area can be considered the “heartland” of Southeast Asia which is very convenient for international trading activities of different countries, especially those from ASEAN including main land and maritime countries. The potentials of the area mentioned above have shown that the Southern part of Vietnam embraces strong geographical, biological and human resources as important conditions for the development of the country. The Southern part has long become great commodity economy area of the country which strongly focusing on exporting as well as contacting and integrating internationally at very early era. In the first decade of the 21st century, the Southern part of Vietnam still plays an important role in the context of international integration and development of the country in the era of industrializing and modernizing. This paper focuses on describing the process of integration of the Southern part of Vietnam in the context of industrialization and modernization era in Vietnam. Consequently, the paper concludes particular traits and foreseen issues regarding the development of the Southern part of Vietnam. Moreover, the role and contribution of this Southern part will be clarified during the common process of industrialization, modernization nation-wide in the new era.

Factors related to dysmenorrhea among Vietnamese and Vietnamese marriage immigrant women in South Korea

ObjectiveTo find factors associated with dysmenorrhea, we surveyed the obstetric and gynecologic histories as well as socioeconomic factors of Vietnamese female residents in Can Tho (southern part of Vietnam) and Bavi (northern part of Vietnam) and Vietnamese female marriage immigrants living in South Korea.MethodsFrom March 2010 to March 2011, 3,017 Vietnamese women aged 17 to 42 years (mean, 25.5 years) were recruited. Socioeconomic factors as well as baseline characteristics, including gynecologic history and menstrual patterns, were collected using questionnaires. The relationships between these factors and dysmenorrhea were analyzed using chi-square test, independent t-test and logistic regression analysis.ResultsDysmenorrhea was found in 58.8% of all women. The mean age and the age at menarche were younger in the women with dysmenorrhea. A longer duration of menstrual flow and severe menstrual volume increased the risk of dysmenorrhea. The prevalence of dysmenorrhea was lower in women who had experienced pregnancy, term delivery and breastfeeding. The prevalence of dysmenorrhea in Vietnamese women was also different according to their educational status. When participants were divided according to their religious preferences, atheist women showed a lower prevalence with 55%, and women who were religious had a higher prevalence of dysmenorrhea. The body mass index, menstrual cycle length, monthly income, and duration of residency in Korea were not related with the prevalence of dysmenorrhea.ConclusionSocioeconomic factors as well as age, menstrual pattern and obstetric history were related with dysmenorrhea in Vietnamese women.

Hepatitis C Virus in Vietnam: High Prevalence of Infection in Dialysis and Multi-Transfused Patients Involving Diverse and Novel Virus Variants

Hepatitis C virus (HCV) is a genetically diverse pathogen infecting approximately 2–3% of the world's population. Herein, we describe results of a large, multicentre serological and molecular epidemiological study cataloguing the prevalence and genetic diversity of HCV in five regions of Vietnam; Ha Noi, Hai Phong, Da Nang, Khanh Hoa and Can Tho. Individuals (n = 8654) with varying risk factors for infection were analysed for the presence of HCV Ab/Ag and, in a subset of positive specimens, for HCV RNA levels (n = 475) and genotype (n = 282). In lower risk individuals, including voluntary blood donors, military recruits and pregnant women, the prevalence of infection was 0.5% (n = 26/5250). Prevalence rates were significantly higher (p<0.001) in intravenous drug users (IDUs; 55.6%, n = 556/1000), dialysis patients (26.6%, n = 153/575) commercial sex workers (CSWs; 8.7%, n = 87/1000), and recipients of multiple blood transfusions (6.0%, n = 32/529). The prevalence of HCV in dialysis patients varied but remained high in all regions (11–43%) and was associated with the receipt of blood transfusions [OR: 2.08 (1.85–2.34), p = 0.001], time from first transfusion [OR: 1.07 (1.01–1.13), p = 0.023], duration of dialysis [OR: 1.31 (1.19–1.43), p<0.001] and male gender [OR: 1.60 (1.06–2.41), p = 0.026]. Phylogenetic analysis revealed high genetic diversity, particularly amongst dialysis and multi-transfused patients, identifying subtypes 1a (33%), 1b (27%), 2a (0.4%), 3a (0.7%), 3b (1.1%), 6a (18.8%), 6e (6.0%), 6h (4.6%), 6l (6.4%) and 2 clusters of novel genotype 6 variants (2.1%). HCV genotype 1 predominated in Vietnam (60%, n = 169/282) but the proportion of infections attributable to genotype 1 varied between regions and risk groups and, in the Southern part of Vietnam, genotype 6 viruses dominated in dialysis and multi-transfused patients (73.9%). This study confirms a high prevalence of HCV infection in Vietnamese IDUs and, notably, reveals high levels of HCV infection associated with dialysis and blood transfusion.