No abstract

BackgroundOut of total 3,081 assembled expressed sequence tags (ESTs) sequences representing 6,815 high-quality ESTs identified in three cDNA libraries constructed with RNA isolated from the midgut of Spodoptera litura, 1,039 ESTs showed significant hits and 1,107 ESTs did not show significant hits in BLAST searches. It is of interest to clarify whether or not these ESTs that did not show hits function in S. Litura.ResultsTwenty “no-hit” ESTs containing at least one putative open reading frame were selected for further expression analysis. The results from northern blot analysis showed that six of the selected ESTs are expressed in the larval midgut of this insect at different levels, suggesting that these ESTs represent true mRNA products, whereas the other 14 ESTs could not be detected. Homologues of the four larval midgut-predominant genes (Slmg2, Slmg7, Slmg9 and Slmg17) were detected in the genomes of other lepidopteran insects but not in Drosophila melanogaster. A novel gene, Slmg7, is expressed at a high level specifically in the midgut during each of the larval stages. Slmg7 is a single copy gene and encodes a 143-amino acids protein. The SLMG7 protein was localized to the cytoplasm of Spli-221 cells.ConclusionsSix ESTs from the no hit list are transcribed into mRNA and are mainly expressed in the midgut of S. litura. Slmg7 is a novel gene that is localized to the cytoplasm.

Effectively prediction of the tourism demand is of great significance to rationally allocate resources, improve service quality, and maintain the sustainable development of scenic spots. Since tourism demand is affected by the factors of climate, holidays, and weekdays, it is a challenge to design an accurate forecasting model obtaining complex features in tourism demand data. To overcome these problems, we specially consider the influence of environmental factors and devise a forecasting model based on ensemble learning. The model first generates several sub-models, and each sub-model learns the features of time series by selecting informative sequences for reconstructing the forecasting input. A novel technique is devised to aggregate the outputs of these sub-models to make the forecasting more robust to the non-linear and seasonal features. Tourism demand data of Chengdu Research Base of Giant Panda Breeding in recent 5 years is used as a case to validate the effectiveness of our scheme. Experimental results show that the proposed scheme can accurately forecasting tourism demand, which can help Chengdu Research Base of Giant Panda Breeding to improve the quality of tourism management and achieve sustainable development. Therefore, the proposed scheme has good potential to be applied to accurately forecast time series with non-linear and seasonal features.

A fatty acid binding protein (FABP) gene (Slfabp1) was cloned from the midgut of Spodoptera litura larvae. The gene consists of four exons and three introns and encodes a peptide of 134 amino acid residues with a predicted molecular mass of 14.7 kDa, which was confirmed by in vitro protein expression. Northern blot and Western blot analyses indicated that both of Slfabp1 mRNA and protein were highly and specifically expressed in the midgut during the fifth and sixth instar feeding larval stages. In situ hybridization and immunohistochemistry analyses confirmed the midgut-specific localization of Slfabp1 mRNA and protein. The result of Western blot showed that expression of the protein was downregulated by starvation and upregulated by refeeding in sixth instar larvae. All of the results taken together suggest that the SlFABP1 plays important role(s) in FA uptake and transport in the midgut during the larval feeding stages of the insect.

In the post-epidemic era, the education of international students coming to China is encountering significant challenges. Based on the current situation of international students studying in China, this paper aims to explore the problems that China is facing up and the corresponding countermeasures to find a way in promoting the development of the work on international students coming to China, which will help cultivate a group of international students who know, love and care about China, and then introduce the Chinese culture to the world.