Effects of residents' tourism development expectation and tourism impacts perception on their attitude towards tourism in natural tourist destination: A Comparative study between China's Jiuzhaigou and the UK's New Forest National Parks

Local residents' perception of tourism impacts in tourist destinations has been found to affect their attitude towards tourism; however, there have been relatively few studies on the influence of residents' tourism development expectation on their attitude towards tourism. With the utilization of SPSS16.0 software, this paper, taking China's Jiuzhaigou and the UK's New Forest National Parks as case study areas, makes a comparative study on the influence of local residents' tourism development expectation and touirism impacts perception on their attitude towards tourism. And potentially possible reasons for the influence and the differences between these two cases have been conducted with a qualitative analysis. Some conclusions can be obtained as follows. (1) Local residents' tourism impacts perception, especially tourism benefit perception, directly influences their support of tourism development. (2) Tourism development expectation of local residents directly influences their tourism impacts perception, espetially their tourism benefit perception, and indirectly influences their attitude towards tourism development in the parks via the medium of tourism benefit perception. (3) Residents in both destinations hold positive tourism development expectation with minor differences between the two cases due to cultural differences. Tourism benefit perception of local residents in the two national parks is less and worse than their tourism development expectation, indicating that there is a great gap between their tourism development expectation and tourism impacts perception in these two case study areas. But the majority of local residents in these two parks still hold no negative attitude towards local tourism development in spite of the existing gap

Simultaneous Quantification of Multiple Licorice Flavonoids in Rat Plasma

Flavonoids are important naturally occurring polyphenols with antioxidant properties. In this study, we report the development of a liquid chromatography tandem mass spectrometry (LC–MS/MS)–based method capable of simultaneously quantifying multiple active licorice flavonoids (including liquiritin apioside, liquiritin, liquiritigenin, isoliquiritin apioside, isoliquiritin, and isoliquiritigenin) in plasma. Electrospray ionization was used to efficiently generate precursor deprotonated molecules of all the analytes and the [M–H]− ions were used to produce characteristic product ions for MS/MS analysis. We found that inclusion of a very low concentration of HCOONH4 (0.01‰) in the LC mobile phase dramatically improved the detection limit for the tested flavonoids and decreased the interference by matrix effects, which have been referred to as “LC-electrolyte effects.” Liquid–liquid extraction with ethyl acetate was effective for isolation of all the analytes and resulted in the lowest matrix effects of several tested sample cleanup methods. This bioanalytical method showed good linearity between 0.32 ng/mL and 1 μg/mL analyte in 50-μL plasma samples. The accuracy and precision at different analyte concentrations varied from 85 to 110% and from 0.8 to 8.8%, respectively. Finally, we demonstrated the applicability of this method in a pilot pharmacokinetic study of rats receiving an oral dose of Xiaochaihu-tang, an important Chinese herbal remedy for chronic hepatitis. The use of a low concentration of HCOONH4 in the LC mobile phase could be used to improve LC–mass spectroscopy- or LC–MS/MS-based methods

Induction de l'expression génique par des petits ARN dans des cellules de mammifère

Chez la plupart des eucaryotes, la présence d ARN double brin induit la mise en place de mécanismes qui peuvent inhiber l expression de gènes sur la base d une complémentarité de séquence. L exemple le mieux connu est le cas de l interférence par l ARN telle qu elle a été décrite initialement chez C. elegans, où les ARN double brin génèrent une endonucléase spécifique de séquence qui dégrade tout ARN parfaitement complémentaire du petit ARN guide contenu dans le complexe RISC. En plus de cette activité post-transcriptionnelle, il a été observé chez de nombreux eucaryotes l existence de mécanismes apparentés à l interférence par l ARN et qui inhibent la transcription en agissant au niveau de la chromatine. Si ces mécanismes ont été clairement mis en évidence chez les plantes et les champignons il n existe que quelques exemples de ce type de régulation chez les mammifères. De manière inattendue, le fait de cibler le promoteur d un gène avec de petits ARN double brin peut conduire à une augmentation de son expression. Cette réponse paradoxale n a été observée jusqu à présent que dans des cellules de mammifère, et si elle suscite un intérêt en particulier pour stimuler l expression de gènes suppresseurs de tumeurs, son mécanisme est encore inconnu.Mes travaux ont porté sur l étude de l induction de l expression par des petits ARN. Ils reposent tout d abord sur le développement d une approche expérimentale qui permet de suivre l activité du promoteur du gène ciblé. Pour cela, j ai utilisé des constructions indicatrices organisées autour d un promoteur bidirectionnel qui contrôle l expression de deux protéines fluorescentes. Lorsque l on cible le messager de l une de ces protéines, l expression de l autre est augmentée et j ai pu montrer que ceci corrèle avec la quantité d ARN messager et de polymérase II présente sur le promoteur bidirectionnel. Ainsi, l utilisation d un promoteur bidirectionnel permet effectivement de suivre le niveau de transcription du gène ciblé par le petit ARN.Cette induction de l expression détectée de manière controlatérale n est pas due à un effet hors cible des petits ARN car elle nécessite la présence de la séquence cible sur l un des transcrits de la construction indicatrice. L induction peut être observée avec de nombreux petits ARN différents, y compris s ils interagissent comme des micro ARN. Les constructions indicatrices que j ai développées sont donc biaisées en faveur d une réponse de type induction transcriptionnelle enréponse à un silencing. L utilisation d un promoteur bidirectionnel est probablement à l origine de ce biais à travers la possibilité d induire une transcription convergente sur les plasmides lorsqu ils sont circulaires. De fait, la linéarisation de la construction indicatrice supprime l induction, du moins pour les constructions les plus simples.Si le coeur du complexe RISC, la protéine Ago2, est nécessaire au silencing et à l induction, j ai pu montrer que dans le deuxième cas c était en fait pour guider le complexe RISC sur les transcrits et non pas pour les couper. En effet, le silencing des protéines TNRC6A et B diminue fortement l induction sans toucher au silencing s il procède en mode siRNA. De plus l ancrage sur le transcrit EGFP induit une réponse de même type que le petit ARN (silencing et induction). Cette approche d ancrage m a permis d identifier les domaines nécessaires au silencing et à l induction et de montrer qu ils sont distincts.Ce travail permet donc de mettre en évidence que l induction transcriptionnelle observée sur nos constructions indicatrices est due à une activité des partenaires des protéines Argonaute, la famille GW182/TNRC6. Cette observation ouvre la voie à une caractérisation du mécanisme de cette induction en montrant qu elle relève d une activité spécifique du complexe RISC.In the majority of the eucaryote, the presence of double-strands RNA induce the inhibition of gene expression base on the complementary of sequence. The best known example is the case of RNA interference in C. elegans which is the first model described, in which the double-strands RNA generate an specific endonuclease who degrade all RNA complementary perfectly to the small RNA guide included in the complex RISC. In addition to this post-transcriptional activity, it has been observed in many eukaryotes the existence of mechanisms related to RNA interference and it inhibit transcription by acting at the chromatin. If these mechanisms have been clearly demonstrated in plants, fungi, there are only several examples of this type of regulation in mammals. Unexpectedly, the targeting the promoter of a gene with small double-stranded RNA can lead to increased expression. This paradoxical response has not been observed so far in mammalian cells, but it raises interest particularly to stimulate the expression of tumor suppressor genes, unfortunely the mechanism is still unknown.My work has focused on studying the induction of expression by small RNAs. They are based first on the development of an experimental approach that allows to monitor the promoter activity of the targeted gene. To do this I used indicator constructions organized around a bidirectional promoter that controls the expression of two fluorescent proteins. When targeting the messenger of one of these proteins, the expression of the other is increased and I was able to show that thisincrease correlates with the amount of RNA messenger polymerase II presented on the bidirectional promoter. Thus, the use of a bidirectional promoter can effectively monitor the level of transcription of the gene targeted by the small RNA. This induction of expression detected in a "contralateral" is not due to an off-target effect of siRNA because it requires the presence of the target sequence on one of the transcripts of the construction indicator. The induction can be observed with many different small RNAs, including the interact as micro RNA. Thus the construction indicator that I developed are biased in an induction response transcriptionally in response to a silencing. The use of a bidirectional promoter is probably the origin of this bias through the possibility of inducing a convergent transcription when the plasmids are circular. In fact, the linearization of the construction indicator removes the induction, at least for the simplest constructions. If the heart of the complex RISC is the protein Ago2, is necessary for the silencing and the induction, I was able to show that in the second case Ago2 was in fact to guide the RISC complex on the transcripts but not to cut it. Indeed, the silencing of proteins TNRC6A and B reduces induction significantly without affecting the silencing if it processe in the siRNA model. Also anchoring the transcript EGFP induces a response similar to the small RNA (silencing and induction). This anchor approach allowed me to identify domaines necessary for silencing and induction and show that they are distinct. This work makes it possible to demonstrate that the transcriptional induction observed in our constructions indicator is due to a activity partner ofArgonaute proteins, the GW182/TNRC6 family. This observation open the way for characterization of the mechanism of this induction by showing that it belongs to a specific activity of the RISC complex.PARIS11-SCD-Bib. électronique (914719901) / SudocSudocFranceF

Bird watching in China reveals bird distribution changes

This article describes the development of the China Bird Watching Database and its use to understand bird distribution changes

Electromagnetic Source Imaging via a Data-Synthesis-Based Convolutional Encoder-Decoder Network

Electromagnetic source imaging (ESI) requires solving a highly ill-posed inverse problem. To seek a unique solution, traditional ESI methods impose various forms of priors that may not accurately reflect the actual source properties, which may hinder their broad applications. To overcome this limitation, in this paper a novel data-synthesized spatio-temporally convolutional encoder-decoder network method termed DST-CedNet is proposed for ESI. DST-CedNet recasts ESI as a machine learning problem, where discriminative learning and latent-space representations are integrated in a convolutional encoder-decoder network (CedNet) to learn a robust mapping from the measured electroencephalography/magnetoencephalography (E/MEG) signals to the brain activity. In particular, by incorporating prior knowledge regarding dynamical brain activities, a novel data synthesis strategy is devised to generate large-scale samples for effectively training CedNet. This stands in contrast to traditional ESI methods where the prior information is often enforced via constraints primarily aimed for mathematical convenience. Extensive numerical experiments as well as analysis of a real MEG and Epilepsy EEG dataset demonstrate that DST-CedNet outperforms several state-of-the-art ESI methods in robustly estimating source signals under a variety of source configurations.Comment: 15 pages, 14 figures, and journa