Search

ObjectiveTo determine the pathogens and drug resistance in patients with bacterial diarrhea in Lishui City of Zhejiang Province from 2015 to 2019， and provide scientific evidence for prevention and treatment of bacterial diarrhea.MethodFecal specimens were collected from patients with diarrhea in the People’s Hospital of Lishui City from 2015 to 2019. Bacteria were identified by time-of-flight mass spectrometer and serum agglutination reaction. Drug sensitivity in the suspected bacteria was identified by VITEK 2 Compact system.ResultsA total of 2 937 fecal samples were tested from 2015 to 2019， of which 191 were positive for bacteria. The prevalence was 6.65% in male and 6.32% in female. It was highest in the age group 21‒30 years old， followed by the group 51‒60 years old. Summer was the season with the highest prevalence of bacteria. Furthermore，the bacterial species included salmonella （3.98%）， Vibrio parahaemolyticus （1.43%）， aeromonas （0.48%）， shigella （0.37%） and other bacteria （3.66%）. Salmonella had high resistance to cefuroxime and amikacin. Vibrio parahaemolyticus and shigella had high resistance to ampicillin. Aeromonas had high resistance to ampicillin and ampicillin/sulbactam.ConclusionPrevalence of bacteria differs by gender， age and seasons in patients with bacterial diarrhea in Lishui from 2015 to 2019. Salmonella is the principal pathogen in bacterial diarrhea. Additionally， multiple drug resistance is commonly identified. Therefore， it warrants strengthening the pathogenic surveillance on bacteria and drug resistance in bacterial diarrhea.

The effect of main chain modification during reversion on strain-induced crystallization (SIC) of unfilled natural rubber (NR) and synthetic polyisoprene rubber (IR) cured with a conventional vulcanization system has been investigated. To eliminate the interference of crosslink density, vulcanizates were prepared using different amounts of curatives, chosen to give mainly monosulfidic or carbon-carbon crosslinks, having similar crosslink densities to the conventional compound at different states of reversion. Crystallinity was characterized by the degree of stress softening, and the contents of irans-methine were qualitatively and quantitatively analyzed by Fourier transform infrared spectroscopy. It was found that crosslink density exerts much greater influence on crystallinity than crosslink structure. At the same crosslink density, SIC of NR vulcanizates after reversion is lower than that of samples cured with tetramethylthiuram disulfide or dicumyl peroxid to the optimum cure state, which might be attributed to molecular main chain modification during reversion. NR was found to have better reversion resistance than IR. KEYWORDS crosslink density and structure, reversion, strain-induced crystallization, stress softening, 1 | INTRODUCTION Natural rubber (NR) has been widely applied in tire industry due to its excellent performance, such as high tensile strength and good crack growth resistance, which are [...]

The volume of natural rubber vulcanizates varied slightly during stretching. Hydrostatic weighing method was adopted in this study to study the volume change. By measuring the volume change of natural rubber compounds filled with different grades and different loadings of carbon black during extension, the corresponding volume variation-elongation ([DELTA]V/V-[epsilon]) curves were created, and the differences of [DELTA]V/V-[epsilon] curves among different carbon black compounds were discussed. The stress differences between different samples were normalized and the [DELTA]V/(V[sigma])-[epsilon] curves were plotted. Scanning electron microscope was utilized to observe the emergence and variation process of cavities in various stretched states. X-ray diffraction was used to explore the change of crystallinity of the rubber after stretching to a certain elongation. Based on the experimental results, the damage at the filler-rubber matrix interface and within the fillers agglomerates would be discussed. KEYWORDS breakdown of agglomerates, cavity, polymer-filler interaction, strain-induced crystallization, volume change, 1 | INTRODUCTION Studies on volume change of vulcanizate during stretching began as early as the 1880s. [1] Schippel [1] reported in 1920 that the density of vulcanizates changed during [...]

Late spring coldness (LSC) is the main limiting factor threatening wheat yield and quality stability. Optimal nutrient management is beneficial in mitigating the harms of LSC by improving wheat root physiology. This study proposed a nutrient management strategy that postponed the application of phosphorus (P) and potassium (K), effectively strengthening wheat's defense against LSC. This experiment used the winter cultivar "Yannong19" (YN 19) as plant material for two consecutive years (2021–2022 and 2022–2023). Two fertilizer treatments were used: traditional P and K fertilizers application (R1: base fertilizer: jointing fertilizer = 10:0) and postponed P and K fertilizers application (R2: base fertilizer: jointing fertilizer = 5:5); wheat plants at the anther connective formation stage shifted to temperature-controlled phytotrons for normal (T0, 11 °C/4 h) and low temperatures (T1, 4 °C/4 h; T2, −4 °C/4 h) as treatments of LSC. The results showed that under low temperature (LT) treatment, compared with R1, the R2 treatment increased the concentrations of osmotic adjustment substances (soluble sugars and soluble protein contents by 6.2–8.7% and 3.0–8.9%), enhanced activities of antioxidant enzymes (superoxide dismutase, peroxidase and catalase activities by 2.2–9.1%, 6.2–9.7% and 4.2–8.4%), balanced the hormone concentrations (increased IAA and GA3 contents by 2.8–17.5% and 10.4–14.1% and decreased ABA contents by 7.2–14.3%), and reduced the toxicity (malondialdehyde, hydrogen peroxide content and O2·− production rate by 5.7–12.4%, 17.7–22.8% and 19.1–19.1%) of the cellular membranes. Furthermore, the wheat root physiology in R2 significantly improved as the root surface area and dry weight increased by 5.0–6.6% and 4.7–6.6%, and P and K accumulation increased by 7.4–11.3% and 12.2–15.4% compared to R1, respectively. Overall, the postponed application of P and K fertilizers enhanced the physiological function of the root system, maintained root morphology, and promoted the accumulation of wheat nutrients under the stress of LSC. [ABSTRACT FROM AUTHOR]

ChatGPT has gained increased attention as an artificial intelligence (AI)‐based tool in the field of tourism and hospitality education in recent years. This study investigates the impact of perceived ease of use, perceived usefulness and authenticity on student attitude and intention to use ChatGPT by incorporating the concept of authenticity into the technology acceptance model (TAM) theoretical framework in tourism and hospitality education. This study found that authenticity had the strongest indirect effect on student intention to use ChatGPT compared with perceived ease of use and perceived usefulness. This study broadens the applicability of TAM theory in ChatGPT and provides practical insights into its application. [ABSTRACT FROM AUTHOR]

We extracted Sal B and TIIA from Salvia miltiorrhiza using enzymatic-assisted ethanol extraction. ACONN predicted optimal process conditions. Enzymolysis and alcohol extraction were used, optimizing conditions and evaluating antioxidant activity. ACONN analyzed data and ACO optimized conditions. Lab verification comprehensively evaluated the conditions. The correlation between Sal B, TIIA, and their antioxidant activities was examined. Weights of 0.5739 and 0.4260 evaluated Sal B and TIIA. ACONN had a 97.46% fitting degree. Optimized extraction conditions improved yield and quality, yielding a comprehensive evaluation value of 27.69 with 4.46% average errors. This approach enhances extraction and compound quality. Antioxidant activity strongly correlated with component yield, influenced by extraction conditions. ACONN-optimized extraction improved Sal B and TIIA yield and quality, with potential as natural antioxidants. Integrating machine learning and optimization algorithms in industrial extraction enhances efficiency and environmental preservation. [ABSTRACT FROM AUTHOR]

Firstly, the relationship between the accuracy of low altitude aerial photogrammetry and the field angle of camera is made by a quantitative analysis from the theory. The conclusion that the low altitude photogrammetry should use wide-angle camera as much as possible is done. Then, the limitation of the single lens camera to expand field angle and the combined wide-angle camera existing on the market not suitable for light load of low altitude UAV(Unmanned Aerial Vehicle) due to excessive weight are pointed out. The characteristics of combined wide-angle low altitude light camera with self-calibration and self-stabilization developed by the author are described, especially the principle of self-calibration for the combination of static error and dynamic error. Based on the practice of large scale mapping, a technical procedure in aerial photography by taking with wide-angle camera and large overlap simultaneously for improving the accuracy of low altitude photogrammetry is proposed. The typical engineering produced data is used to verity the above theoretical analysis. A technical route for increasing accuracy of low altitude photogrammetry with combined wide-angle camera is expounded.