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1.  Fabrication of thickness controllable free-standing sandwich-structured hybrid carbon film for high-rate and high-power supercapacitor 
Scientific Reports  2014;4:7050.
Hybrid carbon films composed of graphene film and porous carbon film may give full play to the advantages of both carbon materials, and have great potential for application in energy storage and conversion devices. Unfortunately, there are very few reports on fabrication of hybrid carbon films. Here we demonstrate a simple approach to fabricate free-standing sandwich-structured hybrid carbon film composed of porous amorphous carbon film and multilayer graphene film by chemical vapor deposition in a controllable and scalable way. Hybrid carbon films reveal good electrical conductivity, excellent flexibility, and good compatibility with substrate. Supercapacitors assembled by hybrid carbon films exhibit ultrahigh rate capability, wide frequency range, good capacitance performance, and high-power density. Moreover, this approach may provide a general path for fabrication of hybrid carbon materials with different structures by using different metals with high carbon solubility, and greatly expands the application scope of carbon materials.
PMCID: PMC4231341  PMID: 25394410
2.  Plasmodium falciparum populations from northeastern Myanmar display high levels of genetic diversity at multiple antigenic loci 
Acta tropica  2012;125(1):53-59.
Levels of genetic diversity of the malaria parasites and multiclonal infections are correlated with transmission intensity. In order to monitor the effect of strengthened malaria control efforts in recent years at the China-Myanmar border area, we followed the temporal dynamics of genetic diversity of three polymorphic antigenic markers msp1, msp2, and glurp in the Plasmodium falciparum populations. Despite reduced malaria prevalence in the region, parasite populations exhibited high levels of genetic diversity. Genotyping 258 clinical samples collected in four years detected a total of 22 PCR size alleles. Multiclonal infections were detected in 45.7% of the patient samples, giving a minimum multiplicity of infection of 1.41. The majority of alleles experienced significant temporal fluctuations through the years. Haplotype diversity based on the three-locus genotypes ranged from the lowest in 2009 at 0.33 to the highest in 2010 at 0.80. Sequencing of msp1 fragments from 36 random samples of five allele size groups detected 13 different sequences, revealing an additional layer of genetic complexity. This study suggests that despite reduced prevalence of malaria infections in this region, the parasite population size and transmission intensity remained high enough to allow effective genetic recombination of the parasites and continued maintenance of genetic diversity.
PMCID: PMC3496066  PMID: 23000544
Plasmodium falciparum; antigenic diversity; border malaria; multiplicity of infection
3.  In Vitro Sensitivities of Plasmodium falciparum Isolates from the China-Myanmar Border to Piperaquine and Association with Polymorphisms in Candidate Genes 
The recent reports of resistance in Plasmodium falciparum to artemisinin derivatives and their partner drugs demand intensive studies toward understanding the molecular mechanisms of resistance. In this study, we examined the in vitro susceptibility of 63 P. falciparum field isolates collected from the China-Myanmar border area to chloroquine (CQ) and piperaquine (PPQ). Parasite isolates remained highly resistant to CQ, with the geometric mean 50% inhibitory concentration (IC50) of 252.7 nM and a range of 51.9 to 1,052.0 nM. In comparison, these parasites had a geometric mean IC50 of 28.4 nM for PPQ, with a fairly wide range of 5.3 to 132.0 nM, suggesting that certain parasite isolates displayed relatively high levels of resistance to PPQ. Interestingly, within the 4 years of study, the parasites exhibited a continuous decline in susceptibilities to both CQ and PPQ, and there was a significant correlation between responses to CQ and PPQ (Pearson correlation coefficient = 0.79, P < 0.0001). Consistent with the CQ-resistant phenotype, all parasites carried the pfcrt K76T mutation, and most parasites had the CVIET type that is prevalent in Southeast Asia. In contrast, pfmdr1 mutations were relatively rare, and no gene amplification was detected. Only the pfmdr1 N1042D mutation was associated with resistance to CQ. For the pfmrp1 gene, four substitutions reached relatively high prevalence of >22%, and the I876V mutation was associated with reduced sensitivity to CQ. However, we could not establish a link between PPQ responses and the polymorphisms in the three genes associated with quinoline drug resistance.
PMCID: PMC3623367  PMID: 23357760
4.  Genetic Diversity and Lack of Artemisinin Selection Signature on the Plasmodium falciparum ATP6 in the Greater Mekong Subregion 
PLoS ONE  2013;8(3):e59192.
The recent detection of clinical Artemisinin (ART) resistance manifested as delayed parasite clearance in the Cambodia-Thailand border area raises a serious concern. The mechanism of ART resistance is not clear; but the P. falciparum sarco/endoplasmic reticulum Ca2+-ATPase (PfSERCA or PfATP6) has been speculated to be the target of ARTs and thus a potential marker for ART resistance. Here we amplified and sequenced pfatp6 gene (∼3.6 Kb) in 213 samples collected after 2005 from the Greater Mekong Subregion, where ART drugs have been used extensively in the past. A total of 24 single nucleotide polymorphisms (SNPs), including 8 newly found in this study and 13 nonsynonymous, were identified. However, these mutations were either uncommon or also present in other geographical regions with limited ART use. None of the mutations were suggestive of directional selection by ARTs. We further analyzed pfatp6 from a worldwide collection of 862 P. falciparum isolates in 19 populations from Asia, Africa, South America and Oceania, which include samples from regions prior to and after deployments ART drugs. A total of 71 SNPs were identified, resulting in 106 nucleotide haplotypes. Similarly, many of the mutations were continent-specific and present at frequencies below 5%. The most predominant and perhaps the ancestral haplotype occurred in 441 samples and was present in 16 populations from Asia, Africa, and Oceania. The 3D7 haplotype found in 54 samples was the second most common haplotype and present in nine populations from all four continents. Assessment of the selection strength on pfatp6 in the 19 parasite populations found that pfatp6 in most of these populations was under purifying selection with an average dN/dS ratio of 0.333. Molecular evolution analyses did not detect significant departures from neutrality in pfatp6 for most populations, challenging the suitability of this gene as a marker for monitoring ART resistance.
PMCID: PMC3608609  PMID: 23555629
5.  Factors associated with willingness to participate in free HIV test among general residents in Heilongjiang, Northeast China 
BMC Infectious Diseases  2012;12:256.
The human immunodeficiency virus (HIV) is spreading from high-risk groups, such as men who have sex with men (MSM) and sex workers, to the general population in China. This study examined the willingness of general residents in Heilongjiang, Northeast China, to participate in free HIV testing in the nearest health care setting, and the factors that may affect participation, including demographic characteristics, HIV-related knowledge, and stigma.
A cross-sectional study was conducted in Heilongjiang Province. All residents aged 15–69 years in two communities in urban areas (September 2007) and four villages in rural areas (April 2008) were recruited using stratified cluster sampling. A total of 4050 residents were interviewed using an anonymous questionnaire. Univariate and multivariate log-binomial regression were used to analyze factors affecting willingness to undergo HIV testing.
The proportions of participants who were willing to participate in free HIV testing was 73.0% in urban residents and 78.8% in rural residents. Multivariate regression analysis among urban participants showed that greater knowledge of HIV transmission misconceptions (relative risk (RR) = 1.02, 95% confidence interval (CI): 1.00–1.04, P = 0.021) and the awareness that an apparently healthy person can be an HIV carrier (RR = 1.12, 95%CI: 1.03–1.21, P = 0.007) was significantly associated with greater willingness to participate in free HIV testing. Among rural participants, greater knowledge of HIV transmission modes (RR = 1.03, 95%CI: 1.01–1.06 P = 0.001) and the awareness that an apparently healthy person can be an HIV carrier (RR = 1.07; 95%CI: 1.01–1.13 P = 0.019) was significantly associated with greater willingness to participate.
The overall level of willingness to accept free HIV testing is high, and is higher in rural residents than in urban residents in Heilongjiang. knowledge of HIV transmission misconceptions and that an apparently healthy person can be a carrier for HIV were associated with willingness to accept free HIV testing among urban residents, while knowledge of HIV transmission modes and that an apparently healthy person can be a carrier for HIV were associated with willingness to accept free HIV testing among rural residents.
PMCID: PMC3482579  PMID: 23057556
HIV; Knowledge; Public stigma; Willingness; General individuals

Results 1-5 (5)