Critical theory and tourism

La posición de la Teoría Crítica somete a juicio a las teorías y perspectivas que velan por lo dominador y la tendencia de explotar a otros como algo natural en los seres humanos. Para el turismo este tipo de teorías sirven para reflexionar no sólo sus contextos conflictivos, sino las tendencias alienantes y enajenadoras de la actualidad. La crítica no se conforma con determinados objetivos, es una “espiral” que no tiene fin, y que para los estudios del turismo esa espiral debe representar la crítica continua, siendo así un proyecto de transformación y cambio teóricoThe position of Critical Theory is against theories and perspectives that ensure the dominator and the tendency to exploit others as something natural in human beings. For tourism this type of theories are used to reflect not only their conflict contexts, but alienating and isolating trends of today. Criticism does not comply with agreed targets is a "spiral" that has no end, and that studies of tourism that should represent the critical spiral continues, making it a project of transformation and change theor

Genomic Characterization of the Guillain-Barre Syndrome-Associated Campylobacter jejuni ICDCCJ07001 Isolate

Campylobacter jejuni ICDCCJ07001 (HS:41, ST2993) was isolated from a Guillain-Barré syndrome (GBS) patient during a 36-case GBS outbreak triggered by C. jejuni infections in north China in 2007. Sequence analysis revealed that the ICDCCJ07001 genome consisted of 1,664,840 base pairs (bp) and one tetracycline resistance plasmid of 44,084 bp. The GC content was 59.29% and 1,579 and 37 CDSs were identified on the chromosome and plasmid, respectively. The ICDCCJ07001 genome was compared to C. jejuni subsp. jejuni strains 81-176, 81116, NCTC11168, RM1221 and C. jejuni subsp. doylei 269.97. The length and organization of ICDCCJ07001 was similar to that of NCTC11168, 81-176 and 81-116 except that CMLP1 had a reverse orientation in strain ICDCCJ07001. Comparative genomic analyses were also carried out between GBS-associated C. jejuni strains. Thirteen common genes were present in four GBS-associated strains and 9 genes mapped to the LOS cluster and the ICDCCJ07001_pTet (44 kb) plasmid was mosaic in structure. Thirty-seven predicted CDS in ICDCCJ07001_pTet were homologous to genes present in three virulence-associated plasmids in Campylobacter: 81-176_pTet, pCC31 and 81-176_pVir. Comparative analysis of virulence loci and virulence-associated genes indicated that the LOS biosynthesis loci of ICDCCJ07001 belonged to type A, previously reported to be associated with cases of GBS. The polysaccharide capsular biosynthesis (CPS) loci and the flagella modification (FM) loci of ICDCCJ07001 were similar to corresponding sequences of strain 260.94 of similar serotype as strain ICDCCJ07001. Other virulence-associated genes including cadF, peb1, jlpA, cdt and ciaB were conserved between the C. jejuni strains examined

Actuation system design with electrically powered actuators

This project addresses the actuation system architecture of future All-electric aircraft (AEA) with electrically powered actuators (EPA). Firstly, the information of EPAs is reviewed, and then an electro-hydrostatic actuator (EHA) and electro-mechanical actuator (EMA) are selected for further system research. The actuation system architecture of Boeing and Airbus is then presented as a conventional design where the new design concepts are also researched and the distributed architecture was proposed as another design trend. To find out which one is better, both of them are selected for further research. The easily available data makes the Flying Crane a better choice for the case study. Stall load, maximum rate and power are the main elements for electric actuator requirements and power consumption, weight, cost and safety are the most important aspects for civil aircraft actuation systems. The conventional and distributed flight actuation system design considered the redundancy of systems and actuators, and also the relationship of the power, control channel and actuator work mode. But only primary flight actuation control system specifications are calculated since this data has better precision and also the limited time has to be taken into consideration. Brief comparisons of the two system specifications demonstrate that the higher power actuator have has higher efficiency and distributed actuators could reduce the system weight through reduce the system redundancy with a power efficiency decline. The electrically powered actuation system for future aircraft design is a balance between actuator number, system weight and power consumption

Finite-Time Backstepping Control for Electro-Hydraulic Servo System via Extended State Observer with Perturbation Estimation Performance Improvement

The extended state observer (ESO) has been widely used in the state and perturbation estimation of the electro-hydraulic servo system. It was found that there was a controlled quantity in the transfer function between the perturbation estimation value and the disturbance. This indicates that the traditional linear ESO’s estimation of the disturbance is affected by the change in the control input. To solve this problem, a new structure ESO for a hydraulic system (LHYESO) was designed by introducing the hydraulic system’s load pressure and system model. The corresponding frequency domain analysis results show that it eliminates the control input in the transfer function and reduces the dependence of the high-frequency domain range of the perturbation estimation on the significant observer gain. To improve the estimation speed, a finite-time convergent ESO for hydraulic systems (FTHYESO) was proposed based on the structure of LHYESO, and it was proved that the observation error converged to a sufficiently small value during a finite time. Moreover, a finite-time backstepping controller has been designed by using the Lyapunov method to guarantee the rapidity and precise response of the hydraulic servo system. Finally, the experiment results show the effectiveness of the proposed method

Finite-Time Backstepping Control for Electro-Hydraulic Servo System via Extended State Observer with Perturbation Estimation Performance Improvement

The extended state observer (ESO) has been widely used in the state and perturbation estimation of the electro-hydraulic servo system. It was found that there was a controlled quantity in the transfer function between the perturbation estimation value and the disturbance. This indicates that the traditional linear ESO’s estimation of the disturbance is affected by the change in the control input. To solve this problem, a new structure ESO for a hydraulic system (LHYESO) was designed by introducing the hydraulic system’s load pressure and system model. The corresponding frequency domain analysis results show that it eliminates the control input in the transfer function and reduces the dependence of the high-frequency domain range of the perturbation estimation on the significant observer gain. To improve the estimation speed, a finite-time convergent ESO for hydraulic systems (FTHYESO) was proposed based on the structure of LHYESO, and it was proved that the observation error converged to a sufficiently small value during a finite time. Moreover, a finite-time backstepping controller has been designed by using the Lyapunov method to guarantee the rapidity and precise response of the hydraulic servo system. Finally, the experiment results show the effectiveness of the proposed method

Proteomic and transcriptomic studies of BGC823 cells stimulated with Helicobacter pylori isolates from gastric MALT lymphoma.

BackgroundThe correlation between the infection of H. pylori and the occurrence of gastric MALT lymphoma (GML) has been well documented. However, the mechanism of how GML is caused by this bacterium is not well understood, although some immunologic mechanisms are thought to be involved.Materials and methodsIn this study, we performed both transcriptomic and proteomic analyses on gastric cancer cells infected by H. pylori isolates from GML patients and the gastric ulcer strain 26695 to investigate the differentially expressed molecular signatures that were induced by GML isolates.ResultsTranscriptomic analyses revealed that the differentially expressed genes (DEGs) were mainly related to binding, catalytic activity, signal transducer activity, molecular transducer activity, nucleic acid binding transcription factor activity, and molecular function regulator. Fifteen pathways, including the Wnt signaling pathway, the mTOR signaling pathway, the NOD-like receptor signaling pathway and the Hippo signaling pathway, were revealed to be related to GML isolates. Proteomic analyses results showed that there were 116 differentially expressed proteins (DEPs). Most of these DEPs were associated with cancer, and 29 have been used as biomarkers for cancer diagnosis. We also found 63 upstream regulators that can inhibit or activate the expression of the DEPs. Combining the proteomic and transcriptomic analyses revealed 12 common pathways. This study provides novel insights into H. pylori-associated GML. The DEPs we found may be good candidates for GML diagnosis and treatment.ConclusionsThis study revealed specific pathways related to GML and potential biomarkers for GML diagnosis

First report of macrolide-resistant and -susceptible Mycoplasma pneumoniae clinical strains isolated from a single case

Objectives: The aim of this study was to investigate the biological characteristics and effect of antibiotic treatment for different Mycoplasma pneumoniae isolates co-infecting the same patient. Methods: Two throat swab specimens from a single patient, on the day of admission (Sp01) and discharge (Sp13), were liquid cultured and subcultured on agar medium to obtain M. pneumoniae monoclones. The 23S rRNA gene of 50 monoclones from specimens Sp01 and Sp13 were analysed. Real-time PCR assay was used for detection of mutations and genotyping. Two typical monoclones were isolated for antimicrobial susceptibility testing. Results: Genotype 1 monoclones accounted for 70.8% (34/48) in Sp01 and 95.7% (44/46) in Sp13. All genotype 1 monoclones were of the 4-5-7-2 multilocus variable-number tandem-repeat analysis (MLVA) type, while all genotype 2 monoclones were 3-5-6-2 MLVA type. The genotype 1 monoclone, which harboured the A2063G mutation in 23S rRNA gene, was resistant to erythromycin and azithromycin in vitro, whilst genotype 2, which did not carry the mutation, was susceptible to macrolides. The proportion of macrolide-resistant M. pneumoniae monoclones in the specimen cultures collected rose from 70.8% to 95.7% at the time of discharge. Conclusion: This is the first report on the isolation of macrolide-resistant and -susceptible strains of M. pneumoniae from the same patient. After treatment, the proportion of macrolide-resistant M. pneumoniae increased, but the patient still carried viable macrolide-susceptible strains, meaning that the macrolide-susceptible strains did not disappear completely

Culture-Independent Detection and Genotyping of Mycoplasma pneumoniae in Clinical Specimens from Beijing, China.

A duplex real-time PCR assay was designed for simultaneous detection and genotyping of Mycoplasma pneumoniae (M. pneumoniae). The detection/typing performance of this duplex PCR method, targeting specific genes for M. pneumoniae type 1 (mpn 459) and type 2 (mpna 5864), was compared to that of the previously published MpP1 real-time PCR assay and the genotyping method for the adhesin P1 gene (mpn 141). A total of 1,344 throat swab specimens collected from patients in Beijing, China were tested for M. pneumoniae by bacterial culture, MpP1 real-time PCR assay, and our duplex PCR assay, and positive detection rates of 26.9%, 34.4%, and 33.7%, respectively, were obtained. The duplex PCR method demonstrated high sensitivity and accuracy for detecting and genotyping M. pneumoniae, and significant differences in genotyping ability were observed when compared to the conventional P1 gene-based method. M. pneumoniae type 1 was the predominate genotype from 2008 to 2012 in Beijing, and a shift from type 1 to type 2 began to occur in 2013. To our knowledge, this is the first reported incidence of a type shift phenomenon of M. pneumoniae clinical isolates in China. These genotyping results provide important information for understanding recent changes in epidemiological characteristics of M. pneumoniae in Beijing

The comparable structural, elastic anisotropic and thermophysical properties of advanced U–Si fuel to baseline UO

Based on a few assumptions regarding crystal construction, the structural, elastic anisotropic and thermophysical properties of advanced U–Si system and baseline UO2 have been investigated through a first-principles density functional theory (DFT) method. The calculated lattice constants are in good agreement with the previous experimental and theoretical values. The elastic properties, including bulk modulus, shear modulus, Young’s modulus, Pugh’s B/G ratio, Poisson’s ratio and elastic anisotropy are derived from the elastic data $${C}_{ij}$$. The calculation results show that the U3Si2 and β-U3Si materials are brittle, while single-crystal UO2 is ductile. Based on Poisson’s ratio, the advanced U–Si compounds and the baseline UO2 compound will have the different elastic deformations. Moreover, the U3Si2 and β-U3Si have elastic anisotropy behavior, while the UO2 with an elastic isotropic characteristic mainly. Finally, Debye temperature, melting point, Voight harness and the hoop stress are predicted through different empirical formulas. The hoop stress of UO2 is larger than that for U3Si2 and β-U3Si. There will be highlight implications of these calculated data for future U–Si fuel pellets’ design and preparation

Fusion of infrared and visible images with Gaussian smoothness and joint bilateral filtering iteration decomposition

Edge‐preserving filters have been applied to Multi‐Scale Decomposition (MSD) for fusion of infrared and visible images. Traditional edge‐preserving MSDs may hardly make satisfied structural separation from details to cause fusion performance degradation. To suppress this challenge, the authors propose a novel fusion of infrared and visible images with Gaussian smoothness and joint bilateral filtering iteration decomposition (MSD‐Iteration). This method consists of three steps. First, source images are decomposed by the Gaussian smoothness and joint bilateral filtering iteration. The implementation includes the fine‐scale detail removal with Gaussian filtering, edge and structure extraction with joint bilateral filtering iteration, and detail obtaining at multi‐scales. The decomposition has edge‐preserving and scale‐aware properties to improve detail acquisition. Second, rules are designed to conduct the layer combination. For the rule of base layers, saliency maps are constructed by Laplacian and Gaussian low‐pass filters to calculate initial weight maps. A guided filter is further applied to determine final weight maps for the combination. Meanwhile, they use the regional average energy weighting to obtain decision maps at multi‐scales by constructing intensity deviation to combine detail layers. Third, they implement the reconstruction with the combined layers. Sufficient experiments are presented to evaluate MSD‐Iteration, and experimental results validate the superiority of the authors’ method