This study uses first-principles calculations to investigate the mechanical properties and effect of strain on the electronic properties of the 2D material 1H-PbX2 (X: S, Se). Firstly, the stability of the 1H Pb-dichalcogenide structures was evaluated using Born’s criteria. The obtained results show that the 1H-PbS2 material possesses the greatest ideal strength of 3.48 N/m, with 3.68 N/m for 1H-PbSe2 in biaxial strain. In addition, 1H-PbS2 and 1H-PbSe2 are direct semiconductors at equilibrium with band gaps of 2.30 eV and 1.90 eV, respectively. The band gap was investigated and remained almost unchanged under the strain εxx but altered significantly at strains εyy and εbia. At the fracture strain in the biaxial direction (19 %), the band gap of 1H-PbS2 decreases about 60 %, and that of 1H-PbSe2 decreases about 50 %. 1H-PbS2 and 1H-PbSe2 can convert from direct to indirect semiconductor under the strain εyy. Our findings reveal that the two structures have significant potential for application in nanoelectronic devices.

Avermectin produced by Streptomyces avermitilis is an anti-nematodal agent against the pine wood nematode Bursaphelenchus xylophilus. However, its potential usage is limited by its poor water solubility. For this reason, continuous efforts are underway to produce new derivatives that are more water soluble. Glycosylation is generally used to enhance the aqueous solubility and biological activity of natural compounds. Uridine diphosphate (UDP)-glycosyltransferase (BLC) from Bacillus licheniformis is involved in the biosynthesis of the bioactive compound by transferring UDP-activated sugar moieties to acceptor molecules. Here, the enzymatic glycosylation of avermectin was catalyzed by uridine diphosphate (UDP) glycosyltransferase from Bacillus licheniformis with various UDP-sugars. As a result, the following four avermectin B1a glycosides were produced: avermectin B1a 4’’-β-D-glucoside, avermectin B1a 4’’-β-D-galactoside, avermectin B1a 4’’-β-L-fucoside and avermectin B1a 4’’-β-2-deoxy-D-glucoside. The avermectin B1a glycosides were structurally analyzed based on HR-ESIMS, 1D and 2D nuclear magnetic resonance (NMR) spectra. The solubility of avermectin B1a4’’-β-D-glucoside and avermectin B1a4’’-β-D-galactoside in water are 49 and 21 times higher than that of avermectin B1a. Consistent with the improved water solubility of avermectin glycosides, the anti-nematodal effect of avermectin B1a4’’-β-D-glucoside was found to exhibit the highest activity,which was approximately 32 times greater than that of avermectin B1a, followed by avermectin B1a 4’’-β-2-deoxy-D-glucoside, avermectin B1a 4’’-β-L-fucoside, and avermectin B1a 4’’-β-D-galactoside. These results show that glycosylation of avermectinB1a effectively enhances itsin vitro anti-nematodal activity and that avermectin glycosides can be further applied for treating infestations of the pine wood nematode B. xylophilus.

Livelihood capitals have a clear influence on livelihood development. As for the livelihood results, it has been pointed out in the analysis of the poor households that the ability of people to escape poverty depends especially on the access to livelihood capitals. This study aims to analyze the impacts of livelihood capital on poverty among mountain people who depend on forests through human capital, social capital, natural capital, physical capital and financial capital. This research employs the model of binary regression function. Independent variables x1, x2, ..., xn are targets of livelihood strategy, vulnerability context, and livelihood capitals. These variables were selected to be included in the original model with dependent variable Y as poor and non-poor households. This study surveys households living in upland areas, near forests, and households of ethnic minorities. The results show that,out of the poor household rate, nearly 4% are newly-poor households or those falling back into poverty. Therefore, the government needs to pay more attention to this disadvantaged group and implements policies such as education and training policies, credit support policies, policies to support forest development, and payment for forest environmental services in the context of emerging countries like Vietnam.,