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This study conducted biostatistical multivariate analyses on 23 craniodental morphological measurements from 209 specimens to study interspecific variations amongst 15 bat species of the genus Myotis in Vietnam. Univariate and multivariate analyses demonstrated that the studied species can be divided into four groups as follows: extra-large-sized species (M. chinensis), large-sized species (M. pilosus, M. indochinensis and M. annectans), medium-sized species (M. altarium, M. hasseltii, M. montivagus, M. horsfieldii, M. ater, M. laniger and M. muricola) and small-sized species (M. annamiticus, M. aff. siligorensis, M. rosseti and M. alticraniatus). Our data revealed that the main craniodental features contributing to the variations in distinguishing Myotis species are the width of the anterior palatal, least height of the coronoid process, length of the upper and lower canine-premolar, zygomatic width and width across the upper canines and lower premolar-molar length. Based on patterns of morphological differences, we conducted comparisons between morphometrically closely resembling species pairs and further discussed additional characteristics that are expected to support the taxonomy and systematics of Vietnamese Myotis bats.

Although Blastocystis sp. is the most common enteric protozoan in human stools worldwide, various geographical areas remain to be investigated regarding the frequency and circulation of this parasite. Such is the case of some developing countries in Southeast Asia that exhibit a higher risk for parasitic infections due to unsanitary conditions. While several epidemiological surveys have been conducted, for instance, in Thailand, little or no data are available from neighboring countries, such as Vietnam. Therefore, in order to determine the prevalence and subtype (ST) distribution of Blastocystis sp. and to clarify the transmission of the parasite, the first molecular epidemiological survey ever conducted in this country was performed. For this purpose, a total of 310 stool specimens were collected from patients enrolled at the Family Hospital of Da Nang and then tested for the presence of Blastocystis sp. by real-time Polymerase Chain Reaction (qPCR), followed by subtyping of the isolates. The overall prevalence of the parasite reached 34.5% in this Vietnamese cohort. No significant association was found between parasite infection and gender, age, symptomatic status, contact with animals or source of drinking water. Out of the 107 positive patients, nearly half presented mixed infections. Therefore, some of the corresponding samples were reanalyzed by end-point PCR, followed by PCR products cloning and sequencing. Of the 88 total subtyped isolates, ST3 was predominant, followed by ST10, ST14, ST7, ST1, ST4, ST6 and ST8. Our study was, thus, the first to report ST8, ST10 and ST14 in the Southeast Asian population. The predominance of ST3 within this Vietnamese cohort, coupled with its low intra-ST genetic variability, reflected a large inter-human transmission, while ST1 transmission was suggested to be not only anthroponotic, but also likely correlated to animal or environmental sources. Strikingly, isolates considered of animal origin (ST6-ST8, ST10 and ST14) accounted for more than 50% of the subtyped isolates. These findings improved our knowledge of the epidemiology and circulation of Blastocystis sp. in Southeast Asia, and in particular, in Vietnam, and highlighted both a major burden of the parasite in this country and a high risk of zoonotic transmission, mainly from poultry and livestock.

Understanding the long-term dynamics of social-ecological systems is critical to better inform sustainable management. Since Holling's adaptive cycle heuristic, published in 2001, substantial progress has been made to explore historical changes in agricultural, pastoral, and forest systems. However, the application of this heuristic in coastal fishery systems has been relatively rare. Using the Tam Giang Lagoon in Vietnam as an example of a rapidly changing environment, we explore the historical behavior of this tropical coastal social-ecological system (SES), associated livelihood pathways, and possible challenges for future livelihood adaptations through the lens of the adaptive cycle metaphor. Our analysis demonstrates that the present lagoon SES condition is the result of a series of historical events and reorganization attempts through two complete adaptive cycles. The lagoon's future vulnerability is tied to the intensification of human uses, prolonged ecological degradation, and intensifying climatic hazards. We show how the evolution of the lagoon SES resulted in divergent livelihood pathways that bring benefits to some users but also cause persistent constraints and sometimes irreversible losses to other users in shared common pool resources. A one-size-fits-all fishery management approach is therefore ill-suited for improving diverse livelihoods. We recommend that fishery policies take seriously the heterogeneity in livelihood pathways for sustainable lagoon management. We end by reflecting on the usefulness of the adaptive cycle heuristic in systematically exploring historical dynamics and identifying underlying drivers and feedbacks between the social and ecological components of complex fishery systems. [ABSTRACT FROM AUTHOR]