Identifying and characterization of novel broad-spectrum bacteriocins from the Shanxi aged vinegar microbiome: Machine learning, molecular simulation, and activity validation.

Shanxi aged vinegar microbiome encodes a wide variety of bacteriocins. The aim of this study was to mine, screen and characterize novel broad-spectrum bacteriocins from the large-scale microbiome data of Shanxi aged vinegar through machine learning, molecular simulation and activity validation. A total of 158 potential bacteriocins were innovatively mined from 117,552 representative genes based on metatranscriptomic information from the Shanxi aged vinegar microbiome using machine learning techniques and 12 microorganisms were identified to secrete bacteriocins at the genus level. Subsequently, employing AlphaFold2 structure prediction and molecular dynamics simulations, eight bacteriocins with high stability were further screened, and all of them were confirmed to have bacteriostatic activity by the Escherichia coli BL21 expression system. Then, gene_386319 (named LAB-3) and gene_403047 (named LAB-4) with the strongest antibacterial activities were purified by two-step methods and analyzed by mass spectrometry. The two bacteriocins have broad-spectrum antimicrobial activity with minimum inhibitory concentration values of 6.79 µg/mL-15.31 µg/mL against Staphylococcus aureus and Escherichia coli. Furthermore, molecular docking analysis indicated that LAB-3 and LAB-4 could interact with dihydrofolate reductase through hydrogen bonds, salt-bridge forces and hydrophobic forces. These findings suggested that the two bacteriocins could be considered as promising broad-spectrum antimicrobial agents.

Two cities, two stages in transforming society-a mixed methods study comparing doctors' adoption of mobile apps for communication with patients in Hangzhou and Yancheng, China.

Objectives: Mobile apps have become commonplace in doctor-patient communication over the last 20 years. Doctors mainly use two kinds of app, social networking apps (i.e., WeChat) and medical platform apps (i.e., Haodf). The purpose of this study was to investigate whether the attributes of social interaction in local society impact doctors' choice of mobile apps to communicate with patients. This article addresses two research questions: (a) To what degree do doctors' adoption patterns in different societies differ? (b) Why do doctors choose certain mobile apps to communicate with patients? Methods: This study employed a mixed methods research design to analyze doctor's adoption behavior patterns in two cities, Hangzhou (HZ) and Yancheng (YC), which represent two stages in transforming society. Various patterns, measured as the percentage of doctors who utilize the medical platform app of Haodf among all doctors and the average service counts per doctor, were compared in three groups of tertiary hospitals: the top ones in HZ, the average ones in HZ, and the average ones in YC. We also conducted thematic content analysis of qualitative data from semi-structured interviews with 20 purposely selected doctors in the two cities. Results: The percentages of doctors who have adopted the app of Haodf from the three groups of tertiary hospitals were 49.97%, 41.00%, and 32.03%, with an average service counts per doctor of 261, 182 and 39, respectively. According to the interviewees, doctors from YC are more likely to use social networking apps to communicate with patients than their HZ counterparts to maintain social connections with their relatives, friends, colleagues, and others. Conclusion: This study demonstrates that doctors' choices of mobile apps are dependent upon social context. In traditional society, where people have close ties, the logic of using social networking apps lies in doctors' need to maximize the utility of their knowledge by maintaining social connections with others. In modern society, where the close ties between people have gradually weakened, the logic of using medical platform apps lies in doctors' needs for reputation marketing, either for themselves or for institutions, their affiliated departments or hospitals.

Perforin-Mimicking Molecular Drillings Enable Macroporous Hollow Lignin Spheres for Performance-Configurable Materials.

Despite the first observations that the perforin can punch holes in target cells for live/dead cycles in the human immune system over 110 years ago, emulating this behavior in materials science remains challenging. Here, a perforin-mimicking molecular drilling strategy is employed to engineer macroporous hollow lignin spheres as performance-configurable catalysts, adhesives, and gels. Using a toolbox of over 20 molecular compounds, the local curvature of amphiphilic lignin is modulated to generate macroporous spheres with hole sizes ranging from 0 to 100 nm. Multiscale control is precisely achieved through noncovalent assembly directing catalysis, synthesis, and polymerization. Exceptional performance mutations correlate with the changes in hole size, including an increase in catalytic efficiency from 50% to 100%, transition from nonstick synthetics to ultrastrong adhesives (adhesion ≈18.3 MPa, exceeding that of classic epoxies), and transformation of viscous sols to tough nanogels. Thus, this study provides a robust and versatile noncovalent route for mimicking perforin-induced structural variations in cells, representing a significant stride toward the exquisite orchestration of assemblies over multiple length scales.

The Synergistic Effects of Aminosilane Coupling Agent on the Adhesion Performance of Silane Primer for Silicone Resin Thermal Protection Coating.

As a bridge between the coating and the substrate, the primer has a direct impact on the adhesion performance of silicone resin thermal protection coating. In this paper, the synergistic effects of an aminosilane coupling agent on the adhesion performance of silane primer were investigated. The results show that silane primer containing N-aminoethyl-3-aminopropylmethyl-dimethoxysilane (HD-103) formed a continuous and uniform film on the surface of the substrate. Two amino groups of HD-103 were conducive to moderate and uniform hydrolysis of the silane primer system, and the introduction of dimethoxy groups was more conducive to the improvement of interfacial layer density and the formation of the planar surface structure, thus enhancing the bond strength at the interface. When the content was 13 wt%, it exhibited excellent synergistic effects on adhesive properties, and the adhesive strength reached 1.53 MPa. The possible morphology and composition of the silane primer layer were investigated by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). A thermogravimetric infrared spectrometer (TGA-IR) was used to analyze the thermal decomposition of the silane primer layer. The results showed that the alkoxy groups in the silane primer were first hydrolyzed to form Si-OH, and then the dehydration and condensation reactions between Si-OH and the substrate formed a firm network structure.

Fabrication of High Thermal Conductivity Nanodiamond/Aramid Nanofiber Composite Films with Superior Multifunctional Properties.

Polymer-based thermally conductive materials are preferred for heat dissipation owing to their low density, flexibility, low cost, and easy processing. Researchers have been trying to develop a polymer-based composite film with excellent thermal conductivity (TC), mechanical strength, thermal stability, and electrical properties. However, synergistically achieving these properties in a single material is still a challenge. To address the above requirements, we prepared poly(diallyldimethylammonium chloride)-functionalized nanodiamond (ND@PDDA)/aramid nanofiber (ANF) composite films using a self-assembly strategy. Owing to a strong interfacial interaction arising from electrostatic attraction, ND particles attract strongly along the ANF axis to form ANF/ND "core-sheath" arrangements. These assemblies self-construct three-dimensional thermally conductive networks through ANF gelation precipitation, which was analyzed as the key parameter for the realization of high thermal performances. The as-prepared ND@PDDA/ANF composite films exhibited high in-plane and through-plane TCs up to 30.99 and 6.34 W/m·K, respectively, at a 50 wt % functionalized ND loading, representing the optimal values among all previously reported polymer-based electrical insulating composite films. Furthermore, the nanocomposites also achieved other properties necessary for realistic applications, such as outstanding mechanical properties, excellent thermal stability, ultra-low thermal expansion coefficient, excellent electrical insulation, low dielectric constant, low dielectric loss, and outstanding flame retardancy. Thus, this excellent comprehensive performance enables the ND@PDDA/ANF composite films to be used as advanced multifunctional nanocomposites in thermal management, flexible electronics, and intelligent wearable equipment.

Institutional trust, scientific literacy, and information sources: What factors determine people's attitudes toward COVID-19 vaccines of different origins in China?

Objective: This study aimed to investigate the different attitudes of Chinese residents toward COVID-19 vaccines produced in China and the United States in an emergency context, and then explored possible explanations for these different attitudes. Methods: Using data collected online in May 2021, we compared Chinese citizens' attitudes toward vaccines originating from China and the US and then adopted ordered logistic models to examine how trust in institutions, scientific literacy, and information sources influence their attitudes toward different vaccines. Results: A total of 2038 respondents completed the survey. Participants reported very different levels of trust in Chinese and American vaccines. The main finding of this paper is that individuals who trust in Chinese institutions, especially those who trust in domestic scientists, typically feel encouraged to also place their trust in domestic vaccines and to distrust those from the US. These individuals' higher evaluation of Chinese government performance makes them more willing to vaccinate with domestic vaccines and less likely to seek US vaccines. Levels of scientific literacy, furthermore, seem to have little influence on attitudes toward different vaccines. Meanwhile, respondents who acquire health information from biomedical journals are more likely to hold a positive view of US vaccines, and these individuals contribute to bridging the gap between levels of trust in Chinese and US vaccines. Conclusions: In contrast with previous findings about Chinese attitudes toward imported vaccines, our respondents are more convinced of the safety and effectiveness of domestic vaccines than of US ones. This trust gap does not arise out of actual disparity in the quality and safety of the different vaccines per se. Instead, it is a cognition concern that is closely bound up with individuals' trust in domestic institutions. People's attitudes toward vaccines of different origins in an emergency context are more influenced by socio-political beliefs than by concern with objective information and knowledge.

Combined enhancement of the propionyl-CoA metabolic pathway for efficient androstenedione production in Mycolicibacterium neoaurum.

BACKGROUND: The production of androstenedione (AD) from phytosterols by Mycolicibacterium neoaurum is a multi-step biotransformation process, which requires degradation of sterol side chains, accompanied by the production of propionyl-CoA. However, the transient production of large amounts of propionyl-CoA can accumulate intracellularly to produce toxic effects and severely inhibit AD production. RESULTS: In the present study, the intracellular propionyl-CoA concentration was effectively reduced and the productivity of the strain was improved by enhancing the cytosolic methyl-branched lipid synthesis pathway and increasing the expression level of nat operator gene, respectively. Subsequently, the application of a pathway combination strategy, combined and the inducible regulation strategy, further improved AD productivity with a maximum AD conversion rate of 96.88%, an increase of 13.93% over the original strain. CONCLUSIONS: Overall, we provide a new strategy for reducing propionyl-CoA stress during biotransformation for the production of AD and other steroidal drugs using phytosterols.

[Analysis on the Spatial Variability Mechanism of the Characteristic Water Quality Factors of Urban River Channel Reclaimed Water].

Due to the limitations of the treatment process of urban sewage treatment plants and the complexity of water sources, the rich inorganic nitrogen and trace persistent organic matter in the reclaimed water cause potential human health risks through lateral leakage or bioaccumulation during the replenishment process of rivers and lakes. Exploring the distribution law of different types of reclaimed water characteristic water quality factors and their formation in reclaimed water replenishment river channels is of great significance to river and lake management. This study takes the Beijing-Tianjin-Hebei section of the North Canal as the research area and explores the spatial variation characteristics of conventional physical parameters, full index, inorganic nitrogen, and salinity hydronium antibiotics in river water quality with the help of clustering, discrimination, principal components, and variance decomposition. The results showed that, although the spatial distribution patterns of different types of water quality factors were consistent, they all showed significant mid-upstream and downstream distribution; however, there were big differences in the degree of variation and the mechanism of variation. The spatial variation of inorganic nitrogen and antibiotics was the most obvious, whereas the variation in conventional physical parameters and the full index was the weakest, and the salinity hydronium showed moderate variation. The spatial variation mechanism of conventional physical parameters was mainly reflected in microbial degradation. The full index was the result of the combined effect of microorganisms, diffusion, the synergy of the two, and a certain degree of source-sink homogeneity. Diffusion was the main mechanism affecting the spatial variation in salinity hydronium. The spatial variation mechanism of inorganic nitrogen was mainly reflected in the source-sink homogenization and microbial degradation; as a secondary mechanism of the spatial variation of inorganic nitrogen, diffusion had a synergistic mode with microbial degradation. Antibiotics, which have great differences in chemical structural stability and biodegradability, showed high spatial variability and had the highest diffusion and microbial synergy mechanism. This research provides a quantitative analysis of the spatial variability mechanism of water quality based on variance decomposition, which has practical guiding significance for the causes of the spatial variability of river pollutants and river management.

[Analysis on Diversity of Plankton Microbial Community in the Beijing-Tianjin-Hebei Section of the North Canal River].

Reclaimed water plays an important role in alleviating the shortage of urban water resources; however, the trace pollutants and pathogens in reclaimed water have an effect on the plankton community in the receiving water. This study investigated the spatial variation mechanism of microbial community diversity in the Beijing-Tianjin-Hebei reach of the Nordkanal River based on the OTUs and phylum level fragment number and fragment abundance data matrix. The results showed that the physical and chemical disturbance caused by the frequent inflow of reclaimed water changed the hydrology and water quality of the water body, and the plankton community could be divided into two different groups along the geographical scale:the medium and upstream clustering (MUC) and the downstream clustering (DC). The analysis of diversity index based on the OTUs data matrix showed that the species diversity of the DC group was significantly higher than that of the MUC group, and the abundance distribution and evenness showed the opposite trend. The species richness was mainly determined by the fragment diversity of the occasional microflora; the evenness was mainly determined by the variation of the abundance of the dominant microflora; the sensitivity of the subcommunity structure with different abundance levels to spatial change was in the order of non-dominant microflora > occasional microflora > dominant microflora. The diversity analysis of the data matrix based on phylum level also showed that the species diversity of the DC group was significantly higher than that of the MUC group, and the change trend of abundance was the opposite; the most sensitive microflora group was the non-dominant phyla, followed by the occasional phyla, and the dominant phyla group was the least sensitive. The data matrix based on the number of level segments of the gate was more sensitive to environmental changes than the multi-degree data matrix based on the level of the gate. The environmental factors significantly related to microbial community were turbidity; permanganate index; oxidation-reduction potential (ORP); macrolide (MLs); tetracycline antibiotic (TCs); and regional response factors of salt ions, carbon, and inorganic nitrogen. In the aspect of abundance and diversity, these phylas that the DC group was significantly more than the MUC group were more significantly negatively correlated with MLs, whereas they were positively correlated with TCs, and these phylas that the MUC group was significantly more than the DC group was more significantly positively correlated with MLs. The research results can provide a theoretical basis and technical guidance for the ecological rehabilitation of urban river courses with reclaimed water as their main water supply source.

Which urban communities are susceptible to COVID-19? An empirical study through the lens of community resilience.

BACKGROUND: After the lockdown of Wuhan on January 23, 2020, the government used community-based pandemic prevention and control as the core strategy to fight the pandemic, and explored a set of standardized community pandemic prevention measures that were uniformly implemented throughout the city. One month later, the city announced its first lists of "high-risk" communities and COVID-19-free communities. Under the standardized measures of pandemic prevention and mitigation, why some communities showed a high degree of resilience and effectively avoided escalation, while the situation spun out of control in other communities? This study investigated: 1) key factors that affect the effective response of urban communities to the pandemic, and 2) types of COVID-19 susceptible communities. METHODS: This study employs the crisp-set qualitative comparative analysis method to explore the influencing variables and possible causal condition combination paths that affect community resilience during the pandemic outbreak. Relying on extreme-case approach, 26 high-risk communities and 14 COVID-19 free communities were selected as empirical research subjects from the lists announced by Wuhan government. The community resilience assessment framework that evaluates the communities' capacity on pandemic prevention and mitigation covers four dimensions, namely spatial resilience, capital resilience, social resilience, and governance resilience, each dimension is measured by one to three variables. RESULTS: The results of measuring the necessity of 7 single-condition variables found that the consistency index of "whether the physical structure of the community is favorable to virus transmission" reached 0.9, which constitutes a necessary condition for COVID-19 susceptible communities. By analyzing the seven condition configurations with high row coverage and unique coverage in the obtained complex solutions and intermediate solutions, we found that outbreaks are most likely to occur in communities populated by disadvantaged populations. However, if lacking spatial-, capital-, and governance resilience, middle-class and even wealthy communities could also become areas where COVID-19 spreads easily. CONCLUSIONS: Three types of communities namely vulnerable communities, alienated communities, and inefficient communities have lower risk resilience. Spatial resilience, rather than social resilience, constitutes the key influencing factor of COVID-19-susceptible communities, and the dual deficiencies of social resilience and governance resilience are the common features of these communities.

Investigating the Relationships Between Public Health Literacy and Public Trust in Physicians in China's Control of COVID-19: A Cross-Sectional Study.

Objective: Public trust in physicians and public health literacy (HL) are important factors that ensure the effectiveness of health-care delivery, particularly that provided during the SARS-CoV-2 pandemic. This study investigates HL as a predictor of public trust in physicians in China's ongoing efforts to control COVID-19. Methods: Data were gathered in February 2020 during the peak of the disease in China. Based on Nutbeam's conceptualization of HL, we measure HL vis-à-vis COVID-19 by using a six-item scale that includes two items each for functional, interactive, and critical HL. Trust in physicians was measured by assessing physicians' capability to diagnose COVID-19. A rank-sum test and ordinal logit regression modeling were used to analyze the data. Results: Two key findings: (a) trust in physician handling of treatment for COVID-19 is reported by about 74% of respondents; and (b) five of the six HL measures are positive predictors of public trust in physician treatment of the disease, with functional HL1 having the highest level of such association (coefficient 0.285, odds ratio 1.33%, p < 0.01). Conclusions: Improving public HL is important for better public-physician relationships, as well as for nations' efforts to contain the pandemic, serving as a possible behavioral, non-clinical antidote to COVID-19. Being confronted with the unprecedented virus, humans need trust. Health education and risk communication can improve public compliance with physicians' requirements and build a solid foundation for collective responses.

Constructing a Novel Xylan-Based Film with Flexibility, Transparency, and High Strength.

Xylan-based films have great potential to replace petroleum-based polymers used for packaging and coatings due to their excellent biocompatibility, biodegradability, and good gas barrier properties. However, fabricating a xylan-based film with flexible, transparent, water-proof, and excellent mechanical properties is an enormous challenge. Herein, we manufactured a series of degradable films with adjustable properties via solution-casting using a water-soluble xylan derivative. This is the first report of a pure xylan-based film with high performance, requiring no additives. The tensile strength of the xylan-based film could be controlled by adjusting the aldehyde content, which varied from 105.0 to 132.6 MPa. The smallest initial water contact angle of the xylan-based films is 93.26°, indicating that these films are hydrophobic. This work shows a simple and viable route toward manufacturing xylan-based films with high tensile strength, flexibility, and transparency, which can be used for packaging materials and coatings.

Rapid fabrication of xylan-based hydrogel by graft polymerization via a dynamic lignin-Fe3+ plant catechol system.

Traditional preparation methods of the hydrogel are not only tedious but also requiring external stimuli. Here, a plant catechol-inspired self-catalytic system (sulfonated lignin and iron ion) has been introduced to rapidly trigger the graft polymerization of vinyl monomers on the carboxymethyl xylan (CMX) at room temperature, generating an elastic, UV-shield, and conductive hydrogel. The rapid preparation process can be finished at room temperature in 5 min without the removal of oxygen. The hydrogel shows charming extension ratio (up to 460%) and tensile stress (up to 23 kPa), which can be ascribed to the double network structure constructed from Fe3+ and CMX. The hydrogel exhibits great transparency (up to 85.37%), fascinating UV-blocking (up to 99%), and conductive features, thereby serving as potential human body sensors. The rapid preparation of xylan-derived hydrogels via dynamic lignin catechol chemistry may open up a new approach to high-valued utilization of biomass.

Probiotics: their action against pathogens can be turned around.

Probiotics when applied in complex evolving (micro-)ecosystems, might be selectively beneficial or detrimental to pathogens when their prophylactic efficacies are prone to ambient interactions. Here, we document a counter-intuitive phenomenon that probiotic-treated zebrafish (Danio rerio) were respectively healthy at higher but succumbed at lower level of challenge with a pathogenic Vibrio isolate. This was confirmed by prominent dissimilarities in fish survival and histology. Based upon the profiling of the zebrafish microbiome, and the probiotic and the pathogen shared gene orthogroups (genetic niche overlaps in genomes), this consequently might have modified the probiotic metabolome as well as the virulence of the pathogen. Although it did not reshuffle the architecture of the commensal microbiome of the vertebrate host, it might have altered the probiotic-pathogen inter-genus and intra-species communications. Such in-depth analyses are needed to avoid counteractive phenomena of probiotics and to optimise their efficacies to magnify human and animal well-being. Moreover, such studies will be valuable to improve the relevant guidelines published by organisations such as FAO, OIE and WHO.

[Analysis of the Spatial Changes in Bacterial Communities in Urban Reclaimed Water Channel Sediments: A Case Study of the North Canal River].

Sediment bacteria have attracted much attention because of their important roles in energy flow and pollutant cycle transformation. The changes in the spatial distribution pattern of bacteria are the basis for research on the biodiversity generation and maintenance mechanisms. However, there are few studies on the spatial variation in benthic microorganisms and its biogeographic models. The highly artificial North Canal River across the Beijing-Tianjin-Hebei area was chosen as the research area in this study. The spatial variation in the different classification levels of the Kingdom, Phylum, Class, Order, Family, Genus, Species, and operational taxonomic units and their diversity formation mechanisms were analyzed. The results showed that the samples at different classification levels had a more homogeneous distribution pattern. There were clearer distribution boundaries at the low classification levels than at the high classification levels. The significance of the bacterial community variation increased as the classification level of the bacterial community decreased. Furthermore, the difference between groups increased and the similarities within groups decreased as the classification level of the bacterial community decreased. The typical rhizosphere microorganisms represented by Frankiales and Rhodobacterales showed significant enrichment in the upstream samples, followed by the midstream samples and a significant decrease in the downstream samples. Microorganisms related to the carbon, nitrogen, and sulfur cycles represented by Anaerolineales and Desulfobacterales showed significant enrichment in the midstream, followed by the downstream and a significant reduction in the upstream. The genus Phenylobacterium was significantly enriched in the upstream followed by the midstream, and was significantly reduced in the downstream. The pathogenic bacteria represented by Clostridium_gasigenes and Moraxella_osloensis showed a significant enrichment pattern in the midstream. The contents of Ca2+, SO42-, and total organic carbon (TOC) in the downstream samples were significantly higher than those in the upstream and midstream samples. The discharge of untreated wastewater downstream increased the salt and TOC contents in the sediment. The ecological restoration project in the sediment of the riparian zone decreased the salt and TOC contents in the upstream and midstream samples. Environmental selection was the main driving factor of the pattern of spatial variation in the bacterial communities in the sediments of the North Canal River.

Research in porous structure of cellulose aerogel made from cellulose nanofibrils.

In this study, a simple strategy to fabricate the cellulose aerogel with homogeneous porous structure and good compression strength properties has been demonstrated. The cellulose aerogel was simply prepared by adding styrene acrylic emulsion (SAE) to the TEMPO-oxidized cellulose nanofibrils (CNF), followed by freeze-drying and oven-heating, in which covalent bond between CNF and SAE was confirmed by FT-IR. Meanwhile, the regulation process of porous structure of cellulose aerogels was investigated by varying the properties of CNF, and the addition of carboxymethyl cellulose (CMC) and SAE. The results demonstrated that the porous structure of cellulose aerogel was gradually improved with increasing carboxyl content of CNF. CMC could effectively increase in specific surface area of cellulose aerogel, achieving a more preferred porous structure due to the elimination of hornification. SAE could highly enhance the uniformity of structure with specific surface area up to 184 m2/g, porosity up to 99%, and successfully improve the strength properties, showing the fabricated cellulose aerogel as a potential cushion packaging material.

Cold-tolerant introgression line construction and low-temperature stress response analysis for bell pepper.

We aimed to screen cold-tolerant introgression lines (ILs) of bell pepper and investigate stress responses of these bell peppers under low temperature. Seedlings of cold-resistant wild-type bell pepper CA157, cultivated bell pepper CA52, and their ILs were evaluated for their tolerance to low temperature. Electrical conductivity measurement was performed on ILs and two parents. Then, contents of physiological and biochemical indexes including malondialdehyde (MDA), proline, and soluble sugar content were examined. Moreover, the superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and peroxidase (POD) activities were further investigated. Finally, the chlorophyll fluorescence (PSII) parameters in all pant leaves were examined.A total of 22 IL plants showed better resistance than their recurrent parent CA52. CL122 was one of the most outstanding plants in ILs that had similar performance with wild bell pepper CA157. Cold resistance analysis based on physiological and biochemical indexes showed that factors such as electrical conductivity, MDA, and PSII were closely related to cold resistance among CA157, CA52, and CL122 under low-temperature stress. In conclusion, ILs constructed in the current study might be used for cold resistance gene introgression between wild and cultured species. Moreover, CL122 might be a novel bridge material for understanding low-temperature response in bell pepper. Furthermore, electrical conductivity, MDA, and PSII might be used to identify the low-temperature resistance of bell pepper plants in a period of obvious differentiation.

Study on Rheological Behavior and Surface Properties of Epoxy Resin Chemical Grouting Material Considering Time Variation.

Epoxy resins are widely used for repairing cracks in stone, mortar and masonry. A main factor that influences the grouting quality is the permeability of grout. However, the permeability will deteriorate over time because of the reaction of chemical grouting materials, which will greatly affect the results of grouting. To the best of our knowledge, there are few reports that focus on the time-varying properties of viscosity and affinity of epoxy resins grouting material. In this paper, we investigate the changing rules of viscosity and affinity with time by studying the viscosity, surface tension and contact angle of the epoxy grouting material. We establish the mathematical model for the time-dependent properties of CW epoxy resin on viscosity and affinity with experimental verification. Moreover, we make a detailed discussion on the modeling of viscosity variation considering both time and temperature. The results show important guiding significance and application value for judging the grout irrigability in the construction process.

Clinical diagnostic value of digestive endoscopic narrow-band imaging in early esophageal cancer.

Clinical diagnostic value of digestive endoscopic narrow-band imaging in early esophageal cancer (EC) and benign lesions was explored. Retrospective analysis was carried out on the clinical data of 186 patients with early EC and benign lesions diagnosed by the Department of Gastroenterology in Cangzhou Central Hospital from February 2011 to April 2018. Among them, 102 patients examined by Narrow Band Imaging (NBI) were regarded as the research group. Eighty-four patients examined by conventional white light staining endoscopy were regarded as the control group. The lesion boundary definition, image clarity, sensitivity, specificity, positive predictive value, negative predictive value, diagnostic compliance rate, detection rate of lesions and adverse reactions were compared between the groups after examination. The results showed that the lesion boundary definition in the research group was higher than that in the control group (P<0.05). The 4-points of image clarity in the research group was higher than that in the control group (P<0.05). The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic compliance rate of the early EC and benign lesions in the research group were higher than those in the control group (P<0.05). The detection rate of the upper, middle and lower segments of lesions in the research group was higher than that in the control group. In conclusion, NBI has higher sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic compliance rate for the diagnosis of early EC and benign lesions. Also it has more accuracy in the detection of lesions and fewer adverse reactions, the screening of early EC and benign lesions is effective, and worth promoting clinically.

Semi-Rational Screening of Probiotics from the Fecal Flora of Healthy Adults against DSS-Induced Colitis Mice by Enhancing Anti-Inflammatory Activity and Modulating the Gut Microbiota.

Ulcerative colitis (UC), a chronic inflammatory bowel disease, substantially impacts patients' health-related quality of life. In this study, an effective strategy for discovering high-efficiency probiotics has been developed. First, in order to survive in the conditions of the stomach and intestine, high bile salt-resistant and strong acid-resistant strains were screened out from the fecal flora of healthy adults. Next, the probiotic candidates were rescreened by examining the induction ability of IL-10 (anti-inflammatory factor) production in dextran sodium sulfate (DSS)-induced colitis mice, and Lactobacillus sakei 07 (L07) was identified and selected as probiotic P. In the end, fourteen bifidobacterium strains isolated from stools of healthy males were examined for their antimicrobial activity. Bifidobacterium bifidum B10 (73.75% inhibition rate) was selected as probiotic B. Moreover, the colonic IL-6 and TNF-α expression of the DSSinduced colitis mice treated with L. sakei 07 (L07) - B. bifidum B10 combination (PB) significantly decreased and the IL-10 expression was up-regulated by PB compared to the DSS group. Furthermore, Bacteroidetes and Actinobacteria decreased and Firmicutes increased in the DSS group mice, significantly. More interestingly, the intestinal flora biodiversity of DSS colitis mice was increased by PB. Of those, the level of B. bifidum increased significantly. The Bacteriodetes/Firmicutes (B/F) ratio increased, and the concentration of homocysteine and LPS in plasma was down-regulated by PB in the DSS-induced colitis mice. Upon administration of PB, the intestinal permeability of the the DSS-induced colitis mice was decreased by approximately 2.01-fold. This method is expected to be used in high-throughput screening of the probiotics against colitis. In addition, the L. sakei 07 - B. bifidum B10 combination holds potential in UC remission by immunomodulatory and gut microbiota modulation.