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Along with its unprecedented economic rise over the past several decades, debates about China's soft power push have become heated. Yet, consensus on what exactly constitutes China's soft power has not been reached. Findings of how resources of Chinese soft power play their roles in the national strategy for global rise are conflicting and lacking empirical rigor. In a much-altered context of China's recent grand initiatives, the prism of higher education and the region of Southeast Asia both are uniquely significant for interpreting soft power agenda of China. This article aims to capture the recent changes in China's soft power through a case study analysing the experiences and perceptions of Cambodian participants from China's higher education programs covering language training, educational development aid, student mobility, and institution/program partnerships. The evidence identifies four emerging resources of Chinese soft power: contemporary life appeal, advancement in science and technology, STEM (science, technology, engineering, and mathematics) education reputation, and economic development model. It further highlights the Belt and Road Initiative as a stimulus for amplifying the influence of the Chinese development model in Southeast Asia, whereas China's domestic coordination of different players and an ideal mix of soft power resources still have not been formulated.

Background: Anopheles maculatus, Anopheles minimus and Anopheles dirus are the major vectors of malaria transmission in the Greater Mekong Subregion (GMS). The malaria burden in this region has decreased significantly in recent years as all GMS countries progress towards malaria elimination. It is necessary to investigate the Anopheles diversity and abundance status and assess the Plasmodium infection rates to understand the malaria transmission potential of these vector species in GMS countries to guide the development of up-to-date vector control strategies and interventions. Methods: A survey of mosquitoes was conducted in Stung Treng, Sainyabuli and Phongsaly Provinces on the Cambodia-Laos, Thailand-Laos and China-Laos borders, respectively. Mosquito collection was done by overnight trapping at sentinel sites in each province. After morphological identification, the 18S rRNA-based nested-PCR was performed to detect malaria parasites in the captured Anopheles mosquitoes. Results: A total of 18 965 mosquitoes comprising of 35 species of 2 subgenera (Subgenus Anopheles and Subgenus Cellia) and 4 tribes (Tribes Culicini, Aedini, Armigerini and Mansoniini) were captured. Tribe Culicini accounted for 85.66% of captures, followed by Subgenus Anopheles (8.15%). Anopheles sinensis dominated the Subgenus Anopheles by 99.81%. Plasmodium-infection was found in 25 out of the 1 683 individual or pooled samples of Anopheles. Among the 25 positive samples, 19, 5 and 1 were collected from Loum, Pangkhom and Siem Pang village, respectively. Eight Anopheles species were found infected with Plasmodium, i.e., An. sinensis, Anopheles kochi, Anopheles vagus, An. minimus, Anopheles annularis, Anopheles philippinensis, Anopheles tessellatus and An. dirus. The infection rates of Plasmodium falciparum, Plasmodium vivax and mixture of Plasmodium parasite species were 0.12% (2/1 683), 1.31% (22/1 683) and 0.06% (1/1 683), respectively. Conclusions: Overall, this survey re-confirmed that multiple Anopheles species carry malaria parasites in the international border areas of the GMS countries. Anopheles sinensis dominated the Anopheles collections and as carriers of malaria parasites, therefore may play a significant role in malaria transmission. More extensive investigations of malaria vectors are required to reveal the detailed vector biology, ecology, behaviour, and genetics in GMS regions in order to assist with the planning and implementation of improved malaria control strategies. [ABSTRACT FROM AUTHOR]

Background: To develop an effective malaria vector intervention method in forested international border regions within the Greater Mekong Subregion (GMS), more in-depth studies should be conducted on local Anopheles species composition and bionomic features. There is a paucity of comprehensive surveys of biodiversity integrating morphological and molecular species identification conducted within the border of Laos and Cambodia. Methods: A total of 2394 adult mosquitoes were trapped in the Cambodia–Laos border region. We first performed morphological identification of Anopheles mosquitoes and subsequently performed molecular identification using 412 recombinant DNA–internal transcribed spacer 2 (rDNA-ITS2) and 391 mitochondrial DNA–cytochrome c oxidase subunit 2 (mtDNA-COII) sequences. The molecular and morphological identification results were compared, and phylogenetic analysis of rDNA-ITS2 and mtDNA-COII was conducted for the sequence divergence among species. Results: Thirteen distinct species of Anopheles were molecularly identified in a 26,415 km2 border region in Siem Pang (Cambodia) and Pathoomphone (Laos). According to the comparisons of morphological and molecular identity, the interpretation of local species composition for dominant species in the Cambodia–Laos border (An. dirus, An. maculatus, An. philippinensis, An. kochi and An. sinensis) achieved the highest accuracy of morphological identification, from 98.37 to 100%. In contrast, the other species which were molecularly identified were less frequently identified correctly (0–58.3%) by morphological methods. The average rDNA-ITS2 and mtDNA-COII interspecific divergence was respectively 318 times and 15 times higher than their average intraspecific divergence. The barcoding gap ranged from 0.042 to 0.193 for rDNA-ITS2, and from 0.033 to 0.047 for mtDNA-COII. Conclusions: The Cambodia–Laos border hosts a high diversity of Anopheles species. The morphological identification of Anopheles species provides higher accuracy for dominant species than for other species. Molecular methods combined with morphological analysis to determine species composition, population dynamics and bionomic characteristics can facilitate a better understanding of the factors driving malaria transmission and the effects of interventions, and can aid in achieving the goal of eliminating malaria. [ABSTRACT FROM AUTHOR]

Background: Few studies have been conducted to investigate the distribution of mosquito vectors and the population structure of secondary vectors in the border region of Cambodia-Laos. The aim of this work was to study the mosquito diversity and molecular phylogeny of secondary vectors, i.e., Anopheles nivipes in this area. Methods: 1440 adult mosquitoes were trapped in the Cambodia-Laos border. mtDNA-COII were amplified and sequenced from 53 An. nivipes DNA samples. Together with COII sequences deposited in GenBank, a total of 86 COII sequences were used for examining population variations, genetic differentiation, spatial population structure, population expansion, and gene flow patterns. Results: The adult mosquitoes were classified into 5 genera and 27 species in this border region. The predominant genera were Culex (60.07%, 865/1440) and Anopheles (31.25%, 450/1440), and the major Anopheles species were An. nivipes (73.56%, 331/450) and Anopheles maculatus (14.22%, 64/450). Based on sequences analysis of COII, a high level of genetic differentiation was reported in two Northwest India (Cheema and Bathinda, Punjab) and Cambodia-Laos (Siem Pang, Stung treng) populations (FST = 0.97824, 0.97343, P < 0.05), as well as lower gene flow (Nm = 0.01112, 0.01365) in the An. nivipes populations. Phylogenetic analysis and SAMOVA revealed a gene barrier restricting gene flow among three An. nivipes populations. Mantel test suggested a significant correlation between geography and gene distance in all An. nivipes populations (Z = 44,983.1865, r = 0.5575, P = 0.0070). Neutrality test and Mismatch distribution revealed a recent population expansion of An. nivipes in the Cambodia-Laos population. Conclusions: Anopheles nivipes was one of the major Anopheles species in the Cambodia-Laos border. Based on sequences analysis of COII, a genetic barrier between Cambodia-Laos and two Indian populations was found, and a recent population expanding or selecting of An. nivipes occurred in the Cambodia-Laos population, suggesting that COII might be an effective marker for describing the molecular phylogeny of An. nivipes. Further investigation and continuous surveillance of An. nivipes are warranted in this region. [ABSTRACT FROM AUTHOR]

Background: Vector control is still a pivotal method for preventing malaria, and its potency is weakened by the increasing resistance of vectors to chemical insecticides. As the most abundant and vital malaria vector in Southeast Asia, the chemical insecticide resistance status in Anopheles sinensis remains elusive in Laos, which makes it imperative to evaluate the true nature of chemical insecticide resistance-associated genetic mutations in An. sinensis in Laos., Methods: Adult An. sinensis were collected from three border regions in Laos. DNA was extracted from individual mosquitoes. PCR amplification and DNA sequencing of a fragment containing codon 1014 of the voltage-gated sodium channel (vgsc) gene were completed to study the kdr allele frequency distribution, kdr intron polymorphism, population genetic diversity, and the evolutionary status of the kdr codon. The mitochondrial cytochrome c oxidase subunit II gene (COII) was amplified and sequenced to examine population variations, genetic differentiation, spatial population structure, population expansion, and gene flow patterns., Results: Nine wild kdr haplotypes of the vgsc gene were detected in this study, and eight of them, namely 1014L1, 1014L2, 1014L4, 1014L7, 1014L9, 1014L10, 1014L11, and 1014L21, were discovered in the China-Laos border (northern Laos), while 1014L3 was only detected in the Thailand-Laos border (northwestern Laos) and Cambodia-Laos border (southern Laos). The newly identified haplotype, 1014L21, was uniquely distributed in the China-Laos border and was not identified in other countries. Based on sequence analysis of the mitochondrial COII genes, significant genetic differentiation and limited gene flow were detected between the China-Laos and Cambodia-Laos An. sinensis populations, which suggested that those two regions were genetically isolated. The distinct distribution of the kdr haplotype frequencies is probably the result of geographical isolation in mosquito populations., Conclusions: Lack of kdr mutations in the vgsc gene was probably due to genetic isolation and the absence of intense selection pressure in the three border regions of Laos. This study reveals that pyrethroid-based chemical insecticides are still appropriate for battling An. sinensis in parts of Laos, and routine monitoring of chemical insecticide resistance should be continuously implemented and focused on more restricted areas as part of chemical insecticide resistance management., (© 2022. The Author(s).)