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In order to accurately monitor CO2 concentration based on the non-dispersive infrared technique, a novel flat conical chamber CO2 gas sensor is proposed and investigated by simulation analysis and experimental verification. First, the optical design software and computational fluid dynamics method are utilized to theoretically investigate the relationship between the energy distribution, absorption efficiency of infrared radiation, and chamber size. The simulation results show that the chamber length has an optimal value of 8 cm when the cone angle is 5° and the diameter of the detection surface is 1 cm, which makes infrared absorption efficiency optimal. Then, the flat conical chamber CO2 gas sensor system is developed, calibrated, and tested. The experimental results indicate that the sensor can accurately detect CO2 gas concentrations in the range of 0–2000 ppm at 25 °C. It is found that the absolute error of calibration is within 10 ppm, and the maximum repeatability and stability errors are 5.5 and 3.5%, respectively. Finally, the genetic neural network algorithm is presented to compensate for the output concentration of the sensor to solve the problem of temperature drift. Experimental results demonstrate that the relative error of the compensated CO2 concentration is varied from −0.85 to 2.32%, which is significantly reduced. The study has reference significance for the structural optimization of the infrared CO2 gas sensor and the improvement of the measurement accuracy.

As an important part of rural members, the success of returning migrant workers’ entrepreneurial activities is not only related to the realization of rural comprehensive revitalization strategy, but also related to the stability of national society. Based on the survey data of 962 returning entrepreneurial migrant workers, combined with social network theory and resource-based theory, based on the dual combined ambidexterity of knowledge resources and operation resources, this paper explores the influence mechanism of rural and urban social network embeddedness combined ambidexterity of returning migrant workers on their entrepreneurial performance. The results show that the embeddedness combined ambidexterity between rural and urban social networks is beneficial to the improvement of entrepreneurial performance of returning migrant workers, and the dual entrepreneurial resources combined ambidexterity of knowledge resources and operation resources play an intermediary role between dual social networks embeddedness combined ambidexterity and entrepreneurial performance. The resource integration ability of migrant workers has a positive moderating effect on the intermediary effect. The research results can provide a reference for the state and government to formulate policies and take measures to improve the entrepreneurial performance of returning migrant workers.

Modern sugarcanes are polyploid interspecific hybrids, combining high sugar content from Saccharum officinarum with hardiness, disease resistance and ratooning of Saccharum spontaneum. Sequencing of a haploid S. spontaneum, AP85-441, facilitated the assembly of 32 pseudo-chromosomes comprising 8 homologous groups of 4 members each, bearing 35,525 genes with alleles defined. The reduction of basic chromosome number from 10 to 8 in S. spontaneum was caused by fissions of 2 ancestral chromosomes followed by translocations to 4 chromosomes. Surprisingly, 80% of nucleotide binding site-encoding genes associated with disease resistance are located in 4 rearranged chromosomes and 51% of those in rearranged regions. Resequencing of 64 S. spontaneum genomes identified balancing selection in rearranged regions, maintaining their diversity. Introgressed S. spontaneum chromosomes in modern sugarcanes are randomly distributed in AP85-441 genome, indicating random recombination among homologs in different S. spontaneum accessions. The allele-defined Saccharum genome offers new knowledge and resources to accelerate sugarcane improvement.

The determination of specific IgE (sIgE) level is of great importance in IgE-mediated food allergies. Our aim was to develop a homogeneous immunoassay—light-initiated chemiluminescent assay (LICA)—for measuring allergen sIgE of a single component in egg white, thus evaluating the LICA-sIgE assay as a useful tool in the diagnosis of food allergy. The LICA-sIgE assay was performed by incubating serum sample with anti-human IgE antibody coated with chemiluminescer beads, streptavidin-coated sensitizer beads, and biotinylated antigens, which consist of four components in egg white. Serum samples from egg allergic patients (n = 70) and healthy volunteers (n = 30) were collected. For calibration, purified human IgE was used as the calibrator. Working conditions of this homogeneous immunoassay were optimized, analytical performance was determined, and correlation of the results between LICA and ImmunoCAP was evaluated. The assays were performed in 8-well plates with a sample volume diluted to 1:10 of 25 μl. Intra-assay precision (% coefficient of variation) ranged from 1.83 to 4.13%, and inter-assay precision ranged from 2.70 to 8.70%. It exhibited excellent sensitivity, which could distinguish between positive samples and negative samples even at a large dilution level. The sIgE-LICA and ImmunoCAP correlated well in patients allergic to single component (r 2 = 0.929). Also, the components ovomucoid and ovalbumin were best at predicting ImmunoCAP results, with the same area under the ROC curve (AUC) of 0.81, and a specificity of 90.0 and 93.3%, respectively. Our data show effective performance characteristics of LICA to detect sIgE in human serum based on component-resolved diagnostic tests (CRD). The homogeneous sIgE-LICA assay has the following key advantages: requires no washing, simplicity and rapidity, reproducibility, high-throughput, good performance in a liquid phase assay, and good suitability for sIgE diagnosis in food allergy based on CRD.

BACKGROUND This study investigated the cardioprotective effect of isosorbide dinitrate (ISDN) postconditioning against rat myocardial ischemia/reperfusion injury in vivo and provided a theoretical basis for clinical application. MATERIAL AND METHODS We randomly divided 32 Wistar rats into 4 groups: sham group, I/R (ischemia/reperfusion) group, I-PostC group (with 3 cycles of 30 s reperfusion and 30 s reocclusion applied at the onset of reperfusion), and P-PostC group (nitrate postconditioning: isosorbide dinitrate (5mg/kg) was given 1 min before reperfusion). The left anterior descending artery (LAD) was occluded for 40 min, followed by a 180-min reperfusion. Relevant indicators were tested. The LAD was occluded again, then we determined the myocardial infarct size. Paraffinized sections were prepared and TUNEL detection was performed. RESULTS There were no significant differences in ischemic sizes between different groups. Compared with the I/R group, the levels of cTnI and myocardial infarct size in the I-PostC group and P-PostC group were significantly decreased (p

To address the problem that SVM is sensitive to outliers and noise points, in order to improve the classification accuracy of SVM, this paper introduces fuzzy theory and intraclass dispersion theory, proposes an improved SVM classification algorithm, uses KFCM and LDA to filter the data set, and selects reasonable training samples, thereby reducing the number of wild points and noise points in the training sample, and thus reducing its impact on the classification effect of the classification model. Compared with the traditional SVM, the algorithm in this paper considers the impact of training samples on the classification effect, introduces fuzzy theory and intra-class dispersion, and eliminates the wild points and noise points in the training samples that affect the classification accuracy of the classification model. Experimental verification shows that the classification accuracy of the SVM classification model trained by the filtered training samples is higher than that of the SVM classification model without the trained training samples.

To find the reason for fermentation failure of surface Douchi during postfermentation, the microbial communities in undersurface and surface samples were investigated using cell counting method and denaturing gradient gel electrophoresis (DGGE). The results showed that the microbial biomass in surface Douchi was obviously different from that in undersurface Douchi even sampled from the same fermentation tanks, and a 10- to 100-fold reduction of microbial cell counts in undersurface had been observed. The bacterial DGGE profile and principal component analysis (PCA) results indicated that only Lactococcus lacts subsp. lactis and Bacillus thermoamylovorans were detected from surface Douchi, while Lactococcus lacts subsp. lactis, Staphylococcus lentus and 2 uncultured strains occupied the dominant positions in undersurface Douchi; when amplified using Bacillus-specific primers, Bacillus thermoamylovorans, Bacillus subtilis, and Enterobacter sp. were found in undersurface Douchi, while only Bacillus thermoamylovorans were detected from surface Douchi; compared to the bacteria and Bacillus, the DGGE profiles and PCA plot of fungi indicated that the fungal community between surface and undersurface Douchi was similar and mainly composed by yeasts. In this study, we detected the microbial biomass and species in postfermentation stage of Douchi, and the various microbial diversity in undersurface and surface samples might be the cause of the fermentation failure in surface fermentation tanks.

BACKGROUND: Douchi is a traditional Chinese soybean food which has been consumed for thousands years as an important protein source and flavouring ingredient. Studies have rarely been carried out to investigate its microbial composition and these are urgently required for the commercial labels and safety considerations. RESULTS: Microbial counts were statistically significant different among Douchi samples. Although the maximum diversity indexes of bacterial, bacillus and fungal polymerase chain reaction–denaturing gradient gel electrophoresis (PCR-DGGE) patterns were only 79%, 70% and 64%, some microorganisms, e.g. Bacillus subtilis, Bacillus amyloliquefaciens, Pseudomonas sp., Saccharomyces cerevisiae and Pichia farinose, were found to share dominant positions in most Douchi samples. In addition, some pathogens, e.g. Staphylococcus saprophyticus, Pantoea sp., Staphylococcus sciuri, Enterobacter sp. and Staphylococcus sp., were also identified. CONCLUSION: The PCR-DGGE technique was used for the first time as an effective method to assess the microbial communities in different Chinese Douchi samples. This information may be useful in improving the product quality, reformatting production methods, extending shelf life and scaling up the fermentation process. Copyright © 2012 Society of Chemical Industry

To track changes in dynamic microbial communities during post-fermentation process, traditional culture method, and denaturing gradient gel electrophoresis (DGGE) were used to study the number and species of dominant microorganisms in douchi. The result of culturedependent method showed that the microbial number changed slightly since the 4th day while the DGGE indicated that the really steady-state was achieved from the 10th day. In addition, Lactococcus lactis subsp., Staphylococcus lentus, and 2 uncultured bacterium were identified to occupy the dominant positions in bacterial DGGE pattern, and Bacillus thermoamylovorans, Bacillus subtilis, Enterobacter spp., and Absidia corymbifera, Pichia guilliermondii, Pichia farinose were also detected from Bacillus and fungal DGGE patterns, respectively. In conclusion, some pathogenic microorganisms involving in the douchi fermentation had been detected throughout the post-fermentation process, and the combination of culturedependent and -independent method was proved to be effective in profiling microbial diversity.

A rapid microbial screening method was developed based on denaturing gradient gel electrophoresis (DGGE). To evaluate the repeatability and reliability of this system, three DGGE markers were used. Then, the feasibility of DGGE method was verified by microbial screenings in viili (a traditional fermented dairy product originated from Scandinavia) and sourdoughs. The results suggested that, this method could efficiently classify the duplicate strains isolated from the complex environment and identify their dominance in microbial ecology if the corresponding environment samples had been provided. This paper proposed the application of polymerase chain reaction (PCR)-DGGE method in reducing the complicated work in microorganism identifications or even directly identified the target strains if a proper DGGE marker had been applied. Key words: Denaturing gradient gel electrophoresis (DGGE), microbial screening, bacteria, fungi, Lactobacillus, bifidobacteria, sourdoughs, viili.

Douchi as a traditional fermentation soyfood with an acquired taste had been appreciated by consumers for thousands of years in China and few Asian countries. Unfortunately, few studies had been conducted on the changes of microbial community during the koji-making process, and whether the pathogenic microorganisms involving the fermentation process is still unclear. Therefore, the PCR-denaturing gradient gel electrophoresis (DGGE) targeting the 16S and 18S rRNA genes was applied to characterise the dynamic changes of Bacteria, Bacilli and Fungi during koji-making process. The results of DGGE showed that eleven species of bacteria, nine species of bacilli and seven species of Fungi had been detected during the koji-making progress, of which the Bacillus subtilis and Aspergillus oryzae belonged to the dominant microorganisms. Also, eleven strains were isolated from Koji-making samples and were identified as B. subtilis, Bacillus amyloliquefaciens, A. oryzae, Brachybacterium sp., Aspergillus niger, Staphylococcus saprophyticus, Micrococcus sp., Staphylococcus gallinarum, Absidia corymbifera, Saccharomyces cerevisiae, Malassezia sp.; Our results revealed that pathogenic microorganisms were involved in the koji-making process, but the probiotic microorganisms occupied the dominant position of community in the koji-making process.

In the version of this article originally published, the accession codes listed in the data availability section were incorrect and the section was incomplete. The text for this section should have read "The genome assembly and gene annotation have been deposited in the NCBI database under accession number QVOL00000000, BioProject number PRJNA483885 and BioSample number SAMN09753102. The data can also be downloaded from the following link: http://www.life.illinois.edu/ming/downloads/Spontaneum_genome/ ." The errors have been corrected in the HTML and PDF versions of the article.

The aim of the present study was to outline any predisposing factors and clinical and radiological features of post-infectious bronchiolitis obliterans (PIBO) in pediatric patients, and to determine the effect of long-term azithromycin treatment on these factors. In total, 16 cases of children with PIBO were retrospectively reviewed. Adenovirus and Mycoplasma pneumoniae were the most common etiological agents (12/16) in the children with PIBO. The patients presented with persistent dyspnea, a chronic cough, sputum production and wheezing following the initial lung infection. Chest X-rays indicated pulmonary overinflation and patchy ground-glass opacity. In addition, high-resolution computed tomography (HRCT) scans revealed patchy ground-glass opacity, bronchiectasis, bronchial wall thickening and mosaic perfusion in all 16 cases. A unilateral hyperlucent lung was observed in two cases. All the patients underwent treatment with low-dose azithromycin and prednisone. Follow-up examinations of the 16 cases, varying in duration between 7 and 31 months, showed that the disease condition had improved in 10 cases. However, no significant improvements were identified from the HRCT scans or were observed in the patient condition in the additional six cases. The diagnosis of BO is primarily based on a typical clinical presentation and HRCT observations. Therefore, a typical clinical history and patchy ground-glass opacity features on HRCT scans are screening indices that predict BO development. Steroids are the cornerstone of BO treatment; however, long-term azithromycin treatment can improve the condition of the patients. In summary, PIBO is a disease with a high morbidity rate and should be treated by a multidisciplinary team. Patients should receive follow-up examination for an extended period. Patchy ground-glass opacity features on HRCT scans indicate that clinical suspicion of BO is necessary in children with persistent and severe wheezing.

To find the reason for fermentation failure of surface Douchi during postfermentation, the microbial communities in undersurface and surface samples were investigated using cell counting method and denaturing gradient gel electrophoresis (DGGE). The results showed that the microbial biomass in surface Douchi was obviously different from that in undersurface Douchi even sampled from the same fermentation tanks, and a 10- to 100-fold reduction of microbial cell counts in undersurface had been observed. The bacterial DGGE profile and principal component analysis (PCA) results indicated that only Lactococcus lacts subsp. lactis and Bacillus thermoamylovorans were detected from surface Douchi, while Lactococcus lacts subsp. lactis, Staphylococcus lentus and 2 uncultured strains occupied the dominant positions in undersurface Douchi; when amplified using Bacillus-specific primers, Bacillus thermoamylovorans, Bacillus subtilis, and Enterobacter sp. were found in undersurface Douchi, while only Bacillus thermoamylovorans were detected from surface Douchi; compared to the bacteria and Bacillus, the DGGE profiles and PCA plot of fungi indicated that the fungal community between surface and undersurface Douchi was similar and mainly composed by yeasts. In this study, we detected the microbial biomass and species in postfermentation stage of Douchi, and the various microbial diversity in undersurface and surface samples might be the cause of the fermentation failure in surface fermentation tanks.

Viili, also known as viilia, is a traditional fermented dairy product, which is popular in Finland. However, little research has been conducted on organisms’ isolation and their interaction during milk fermentation. In this study, culture-dependent and independent methods had been used to identify isolates. Also, their synergistic effects on milk curd and exopolysaccharides (EPSs) yield was evaluated. When Lactobacillus plantarum, Streptococcus thermophilus, Lactobacillus paracasei, Bacillus cereus and Lactobacillus delbrueckii were successfully separated and screened from viili by using the combination of conventional microbiological cultivation with polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE), they were individually inoculated into sterilized skimmed milk or combined as co-cultures to determine the curd time and the yield of EPSs. Results show that L. delbrueckii presented the strongest curding capability at 5 h and combination of L. paracasei, B. cereus and L. plantarum brought the highest yields of EPSs (186.71 mg/L). Moreover, it suggested that the synergistic effects among the isolates had shortened the curding time and increased the production of EPSs. Key words : Viili, PCR-DGGE, exopolysaccharides, lactic acid bacteria.

Douchi is a traditional Chinese soybean food which has been consumed for thousands years as an important protein source and flavouring ingredient. Studies have rarely been carried out to investigate its microbial composition and these are urgently required for the commercial labels and safety considerations.Microbial counts were statistically significant different among Douchi samples. Although the maximum diversity indexes of bacterial, bacillus and fungal polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) patterns were only 79%, 70% and 64%, some microorganisms, e.g. Bacillus subtilis, Bacillus amyloliquefaciens, Pseudomonas sp., Saccharomyces cerevisiae and Pichia farinose, were found to share dominant positions in most Douchi samples. In addition, some pathogens, e.g. Staphylococcus saprophyticus, Pantoea sp., Staphylococcus sciuri, Enterobacter sp. and Staphylococcus sp., were also identified.The PCR-DGGE technique was used for the first time as an effective method to assess the microbial communities in different Chinese Douchi samples. This information may be useful in improving the product quality, reformatting production methods, extending shelf life and scaling up the fermentation process.