With the acceleration of urbanization and industrialization, the migration of rural labor force has led to the decline of rural industries and communities. As one important way to adjust the rural ...industrial structure and revitalize rural culture, rural tourism has developed through the rural revitalization strategy and the leisure tourism transformation. In this context, with the use of idle housing resources, homestay inns are meeting consumers' increasing demand for leisure, while also improving facility capability regarding rural tourism, maintaining local landscape, and becoming an important industry for rural tourism. Thus, we took southern Jiangsu and northern Zhejiang, which have strong economic power and close regional cooperation, as examples, and used the location retrieval service in the Baidu Map API to obtain information on homestay inns. Then, we analyzed the spatial distribution characteristics of homestay inns with the help of ArcGIS, and Geodetector was used to further analyze the influencin
Interleukin-8 (IL-8) functions as a major chemoattractant and plays pivotal roles in the initiation and development of chronic obstructive pulmonary disease (COPD), and tobacco smoke is a most risk ...factor contributing to the development of COPD. Hence, we have screened some of the tobacco smoke-derived chemical compounds that potentially induce the production of IL-8 in human bronchial epithelium, 16HBE cells.
Twenty-eight hazardous smoke components belonging to 9 classes including nicotine, ammonia, aromatic amines, polycyclic aromatic hydrocarbons, phenols, carbonyls, hydrocyanic acid, nitrosamines and other volatile organics were used in the experiments. Proliferation of 16HBE cells was determined by cell counting kit-8 kit, luciferase activity was measured in IL-8 reporter gene-expressing 16HBE cells, and IL-8 levels in culture supernatants were quantified by enzyme-linked immunosorbent assay.
At the non-toxic dosages, chemical compounds belonging to nicotine, aromatic amines, benzopyrene, phenols, aldehydes, and some other volatile organics dose-dependently increased IL-8 reporter gene expression. Consistently, the representative compounds belonging to nicotine, aromatic amines, benzopyrene, phenols, aldehydes, and some other volatile organics significantly and dose-dependently increased IL-8 levels in the culture supernatants of 16HBE cells, among these compounds, benzopyrene is a most potent stimulator for inducing IL-8 production.
The present study has identified particular tobacco smoke constituents responsible for inducing the IL-8 production in human bronchial epithelium, which might help shed light on the pathogenesis of tobacco smoke-induced COPD.
Pre-processing of near-infrared (NIR) spectral data has become a necessary part of chemometrics modeling and is widely used in many practical applications. The objective of the pre-processing is to ...remove physical phenomena in the spectra in order to improve subsequent qualitative or quantitative analysis. Herein, a localized version of standard normal variate (SNV) is proposed, in which the correction parameters are estimated from local spectral areas. The method of determining the optimal spectral segmentation is also presented. Compared with full range methods, the local method demonstrates advantages in spectral linearity correction, model interpretation and prediction accuracy. Several benchmark NIR data sets were studied in our experiments; the proposed method achieved comparable performance against proven full range methods, with the reduction of prediction errors being statistically significant in many cases.
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•A local pre-processing algorithm is proposed for near-infrared spectra.•The optimal segmentation of local areas can be automatically determined by a cross validation scheme.•Experiments show that the proposed local method outperformed the full range pre-processing methods.•The proposed method has no manual parameter and can be easily used in many applications.
Two mutants of
E. coli with deletion of
sdhAB and
ackA-pta genes respectively and their wild-type strains were subjected to gas chromatography-flame-ionization detection (GC-FID) and gas ...chromatography-mass spectrometry (GC–MS) metabolomics analysis. Intracellular metabolites of the three strains were profiled by GC-FID firstly. Methodological evaluation of the employed platform indicated that the limit of detection ranges were from 0.2 to 12.5
ng for some representative metabolites and the corresponding recoveries were varied from 68.7 to 122.7%. Secondly, multivariable data analysis was applied to the acquired data sets. As expected, the three phenotypes could be easily differentiated, and the perturbed metabolite pools in the genetically modified strains were screened. Lastly, the metabolites playing key roles in the differentiation were further identified by GC–MS. It was confirmed that succinic acid and aspartic acid were similarly affected in the modified strains. But proline content was altered contrarily. Additionally, deletion of
sdhAB gene also affected the growth property of relevant mutant greatly. The potential mechanism was postulated accordingly.
Global climate change is one of the most pressing issues in today's world and all countries are concerned with reducing carbon dioxide emissions. Carbon dioxide emissions from tourism transport have ...to be monitored to enable sustainable tourism development in the 21st century, particularly as fossil-fuel energy sources are becoming scarce. We use the substitutional bottom-up analysis method to calculate the carbon dioxide emissions from tourism transport in the the Yangtze River Delta area. This analysis method is used for the first time. Based on a region's per capita GDP, per capita income and transport route distance per vehicle, we calculated that the daily tourism distances per person in Jiangsu Province, Zhejaing Province, and Shanghai were 3.43, 3.61 and 5.12 km in 2011, respectively. Our results indicate that tourism catchment area is an important factor and this needs to be balanced with convenient transport links, residents' tourism preferences, and the distribution of tourism destinations in each province.
Analyzing tourists’ perceptions of air quality is of great significance to the study of tourist experience satisfaction and the image construction of tourism destinations. In this study, using the ...web crawler technique, we collected 27,500 comments regarding the air quality of 195 of China’s Class 5A tourist destinations posted by tourists on Sina Weibo from January 2011 to December 2017; these comments were then subjected to a content analysis using the Gooseeker, ROST CM (Content Mining System) and BosonNLP (Natural Language Processing) tools. Based on an analysis of the proportions of sentences with different emotional polarities with ROST EA (Emotion Analysis), we measured the sentiment value of texts using the artificial neural network (ANN) machine learning method implemented through a Chinese social media data-oriented Boson platform based on the Python programming language. The content analysis results indicated that in the adaption stage in Sina Weibo, tourists’ perceptions of air quality were mainly positive and had poor air pollution crisis awareness. Objective emotion words exhibited a similarly high proportion as subjective emotion words, indicating that taking both objective and subjective emotion words into account simultaneously helps to comprehensively understand the emotional content of the comments. The sentiment analysis results showed that for the entire text, sentences with positive emotions accounted for 85.53% of the total comments, with a sentiment value of 0.786, which belonged to the positive medium level; the direction of the temporal “up-down-up” changes and the spatial pattern of high in the south and low in the north (while having little difference between the east and the west) were basically consistent with reality. A further exploration of the theoretical basis of the semi-supervised ANN approach or the introduction of other machine learning methods using different data sources will help to analyze this phenomenon in greater depth. The paper provides evidence for new data and methods for air quality research in tourist destinations and provides a new tool for air quality monitoring.
The study of constraints in the leisure and tourism context has been a growing research theme during the past four decades. This article focused on participants' constraints that inhibit an ...experience of Chinese calligraphic landscapes. The purpose of this study was to determine whether three types of constraints existed in the context of a calligraphic landscape experience. A confirmatory factor analysis confirmed the fitness of the collected data for the hierarchical constraints model. This study also extended this hierarchical model to prove that some constraint dimensions do influence tourists' preference, participation and satisfaction. This research concluded that intrapersonal constraints had a negative influence on preference, while neither interpersonal nor structural dimension influenced tourists' participation or satisfaction.
► Our study focuses on the special culture landscape: Chinese calligraphic landscape. ► Constraints to calligraphic landscape experience is defined. ► We developed a measurement scale of constraints in such context. ► The hierarchical structure of constraints is confirmed in such context. ► Constraints do not all affect preference, participation and satisfaction.
Extracting experimental stimulus reviews that contain complete information can provide a new research perspective for comparing the usefulness of reviews from different platforms. Using the tourism ...reviews from Sina Weibo and Ctrip, which represent community-based and transactional platform reviews, respectively, as source materials, a set of extracted reference standards was first developed, and an extended information adoption model was constructed to explore the influence of review type and review quality on usefulness. The results showed that the usefulness of transactional reviews was significantly higher than that of community-based reviews, that the perception of affective information and the cognitive aspect of the perception of price information played a partial mediating role in the process of review type influencing usefulness, and that the value of frugality moderated the main effect. This study enriches the connotation of the information adoption model and has great reference value for information search and related marketing efforts.
Kawasaki disease (KD), as one of the most common vascular diseases in children, will cause the risk of coronary artery lesions (CAL) without treatment. This study is to explore the expression of ...procalcitonin (PCT), brain natriuretic peptide (BNP), tumor necrosis factor-α (TNF-α), C-reactive protein (CRP) and interleukin-6 (IL-6) in children with KD and their correlation with CAL.
86 KD children in Baoding Hospital of Beijing Children's Hospital were selected as the study subjects from January 2020 to June 2021. According to whether CAL occurred, they were divided into the CAL group (n=30) and NCAL group (n=56). The clinical data of the two groups were collected from the medical record system. The levels of PCT and BNP were detected by chemiluminescence microparticle assay, the CRP level was detected by immunoturbidimetry, and the levels of TNF-α and IL-6 were detected by flow immunofluorescence method. The relationship of PCT, BNP, and inflammatory factors with CAL in KD children was explored by Pearson correlation analysis.
The comparative result of clinical data showed no overt difference in gender, disease types, age and blood routine indexes between the two groups, except for coronary artery diameter (P >.05). The levels of PCT, BNP, CRP, TNF-α and IL-6 in CAL group were (1.70±0.39) μg/L, (289.21±29.78) ng/L, (83.16±17.35) mg/L, (9.38±1.23) pg/mL and (59.97±0.97) ng/mL, respectively. The levels of PCT, BNP, CRP, TNF-α and IL-6 in NCAL group were (1.04±0.18) μg/L, (170.85±23.58) ng/L, (69.70±16.64) mg/L, (6.32±0.73) pg/mL and (44.16±11.97) ng/mL, respectively. The levels of each index in the CAL group were notably higher than in the NCAL group (P < .001). Pearson correlation analysis revealed that PCT, BNP, CRP, TNF-α and IL-6 were positively correlated with CAL in KD children (r=0.829, 0.865, 0.823, 0.894, 0.784, P < .001).
The increase of PCT, BNP, and inflammatory factors has a certain warning effect on CAL in KD children. In clinical practice, health care professionals should strengthen the detection of PCT, BNP and inflammatory factors in KD children, carry out early monitoring of CAL in children with high expression of biomarkers, and formulate personalized preventive intervention based on the disease progress, so as to reduce the risk of cardiovascular disease. However, due to the limitations of research conditions and methods, the sample size of this study is small, which may affect the reliability and representativeness of the conclusion. In order to provide a new direction for the clinical prevention and treatment of the disease, future work will improve the research design, expand the sample size, and carry out more in-depth exploration on the prediction of CAL in KD children.
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