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The concrete composition of different pipelines varies greatly, and a comprehensive analysis of the impact of concrete design on pipeline corrosion is required. Developed an integrated model based on Scikit-Optimize, XGBoost and SHAP to analyze concrete's carbonation and sulfuric acid resistance from five aspects: binder type, supplementary cementitious material (SCM's), aggregate, admixture and w/b. Choose Scikit-Optimize for parameter optimization. As an explanation model, the SHAP model can perform analysis well and explain the analysis basis of the XGBoost training model. The established model can accurately predict the corrosion effect (R2 >0.987) without overfitting. Binder should be maintained at 380 to 400 (kg/m3). Water/binder and coarse aggregate/binder are the two main factors that influence the binder, and they should be maintained at a ratio of around 0.4 to 0.6 and 2.5, respectively. Fly ash (FA) should be SCM's used as at a range of 300 to 350 (kg/m3) to improve corrosion resistance. [ABSTRACT FROM AUTHOR]

This study investigated the effect of environmental parameters on microbial-induced concrete corrosion during three corrosion stages. The corrosion effects and influencing factors in three corrosion stages were deeply analyzed and predicted, and the mechanism of microbial corrosion was summarized. When the H2S concentration was lower than about 15.0 mg/m3, the corrosion was maintained in stage II, which greatly delays the intensification of corrosion. In stage III, the H2S concentration has the significantly accelerate the corrosion rate. Additionally, incorporating min, max and mean values of input parameters greatly improved the accuracy of machine learning predictions of corrosion rates (R2 >0.99). Acidithiobacillus was found to be dominant in the microbial community at H2S concentrations of 12.0–37.5 mg/m3, and increased temperature promoted the reproduction of Acidithiobacillus. [ABSTRACT FROM AUTHOR]

Cyanobacterial bloom elimination has become an urgent concern in aquatic environment protection. Allelopathic technology, however, is one of the potential effective approaches because of its exclusive and ecological safety protection. The potential application of chitosan fiber in the inhibition of Microcystis aeruginosa was explored for the first time. Results showed that the cell growth of M. aeruginosa was inhibited effectively by chitosan fibers. After 12 days of treatment, the inhibition rate (IR) of algal cells was above 78.9%; those of chlorophyll a and carotenoids in algal cells were 86.9% and 93.1%, respectively; those of phycocyanin, allophycocyanin and phycoerythrin in phycobiliproteins were all approximately 100%; those of soluble proteins and algal toxins were 88% and 100%, respectively; and those of superoxide dismutase and catalase activities were 68% and 74%, respectively. In addition, chitosan fiber effectively destroyed the structure of algal cells involved in the photosynthetic process, thereby destroying the metabolic activity of algal cells. This study provides a novel method utilizing a new allelopathic material.

(1) Background: Evidence suggests that aerobic exercise and high-intensity interval training (HIIT) might increase fat oxidation and reduce fat. However, limited research has examined the effects of combining progressive aerobic exercise and HIIT interventions in sedentary adults with overweight and obesity, and differences in its effects between men and women remain unclear. The purpose of this study was to investigate the effects of combined progressive aerobic exercise and HIIT (CAEH) on fat oxidation and fat reduction in sedentary Chinese adults and compare sex differences in sedentary adults after seven weeks. (2) Methods: Eighty-four sedentary obese adults were enrolled and allocated to two groups in baseline (experimental (EXP) group:42; control (CON) group:42), and fifty-six subjects (EXP:31; CON:25) completed the experiments and were included in the final analysis. Subjects in the EXP group performed CAEH three times per week for seven weeks. Subjects in the CON group were advised to continue with their normal daily activities. Anthropometric, lipid profile, cardiorespiratory fitness, and fat oxidation outcomes were assessed before and after the intervention. (3) Results: After seven weeks of the CAEH intervention, compared with the CON group, the EXP group showed significant increases in fat oxidation at rest (FO_rest) (+0.03 g/min, p < 0.01), maximal fat oxidation (MFO) (+0.05 g/min, p < 0.01), and maximal oxygen intake (VO2max) (+3.2 mL/kg/min, p < 0.01). The changes in the percentages of the FO_rest (+57%) and the VO2max (+16%) were significantly greater (+20%, +6%) in males than in females (p < 0.05, p < 0.05). The body mass index (BMI) (−1.2 kg/m2, p < 0.01), body fat percentage (−3.2%, p < 0.001), visceral fat area (−12.8 cm2, p < 0.001), and total cholesterol (TC) levels (−0.4 mmol/L, p < 0.05) were significantly decreased in the EXP group. (4) Conclusions: Seven weeks of the CAEH intervention effectively improved FO_rest, MFO, and VO2max in sedentary obese adults, and the improvements in FO_rest and VO2max were more pronounced in males than in females. CAEH also improved body composition and TC levels in sedentary obese adults. [ABSTRACT FROM AUTHOR]

A low-carbohydrate, high-fat (LCHF) diet has been proposed to enhance the fat utilization of muscle and the aerobic capacity of endurance athletes, thereby improving their exercise performance. However, it remains uncertain how the macronutrient intake shift from carbohydrate to fat affects endurance exercise training and performance. This study performed a systematic review and meta-analysis to explore the effects of a ketogenic low-carbohydrate, high-fat (K-LCHF) diet on aerobic capacity and exercise performance among endurance athletes. Searches were carried out in five electronic databases, and we followed the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. The search included studies using an LCHF diet as an intervention protocol and compared data on factors such as maximum oxygen uptake (VO2max) and rating of perceived exertion (RPE) from the graded exercise test. In this case, 10 studies met the criteria and were included in the meta-analysis. We did not find a significant effect of K-LCHF diet interventions on VO2max, time to exhaustion, HRmax or RPE. However, a significant overall effect in the substrate oxidation response to respiratory exchange rate was observed. The meta-analysis showed that K-LCHF diets did not affect aerobic capacity and exercise performance. Therefore, high-quality interventions of a K-LCHF diet are needed to illustrate its effect on various endurance training programs. [ABSTRACT FROM AUTHOR]

Zeolite imidazole framework materials (ZIFs) are a new type of antibacterial material with high chemical and thermal stability, and good antibacterial effect. However, powder ZIFs materials have the disadvantages of difficult separation and easy aggregation, which limit their application. In this work, ZIFs and chitosan (CS) were compounded by in-situ growth method to prepare a new antibacterial agent. The synergism of CS and ZIFs can effectively promote antibacterial effect compared with CS and pristine ZIFs, and CS/ZIF-67(1:6) has the best antibacterial activity, and its inhibitory rate (in 15 h) of E. coli is 96.75%, and the inhibitory rate of S. aureus reaches as high as 100%. This composites can effectively cause bacterial cell membrane rupture and leakage of internal nucleic acid and protein, leads to achieve antibacterial effect, and also exhibit excellent long-term (at least 5 days) antibacterial properties, the leaching of cobalt is below than 0.5 mg·L−1, and this composites are with excellent bio-compatibility. • Chitosan and ZIFs are compounded by in-situ synthesis. • Chitosan could well disperse ZIFs. • Chitosan promotes ZIF to perform better antibacterial activity. [ABSTRACT FROM AUTHOR]

Abstract The starch-palmitic acid complex was prepared by the reaction of different concentrations (0.1%–5.0%) of palmitic acid and yam starch. In order to find out the effects of concentration of palmitic acid on the properties of the complex, the physicochemical properties, morphological properties, freeze-thaw stability, antioxidant activity and bile acid binding capacity of complexes were studied. It was found that with the increase of palmitic acid concentration, the complex index of starch-fatty acid increased first and then decreased. When the concentration of palmitic acid was 2%, the complex index was the highest (26.39%). The crystal type has gradually changed from Ca type into mixtures of V-type pattern and B-type pattern when introduced palmitic acid. The water binding capacity, solubility, swelling power and paste clarity were decreased, while the content of resistant starch and freeze-thaw stability were obviously increased. Compared with the native starch, the antioxidant activity and bile acid binding capacity of the complex were significantly increased. All the result showed that the concentration of palmitic acid has a great influence on the physicochemical properties of modified starch and the starch-palmitic acid complexes have higher ability of controlling cholesterol and improving the anti-oxidant activity than native yam. Highlights • Different concentration of palmitic acid-yam starch complexes were prepared. • When the concentration of palmitic acid was 2%, the complex index was the highest. • The palmitic acid-yam starch complex exhibited significant antioxidant activity and bile acid binding capacity. • 2% should be the optimum concentration of palmitic acid combined with yam starch. [ABSTRACT FROM AUTHOR]

With its advantages of ecological safety, environmental affinity, and high selectivity, allelopathic technology has been widely developed for algae inhibition. However, obtaining effective allelochemicals and realizing their mechanism are difficult. In this paper, a Chinese herbal medicine, namely, Rheum palmatum L. (Chinese rhubarb), was utilized as a source of allelopathic substances for the first time. Four units of rhubarb organic extracts were collected to study the inhibition of growth, photosynthesis, proteins, and algal toxin of Microcystis aeruginosa. Results showed that the ethyl acetate, n-butanol, and aqueous phases of the rhubarb extracts have notable inhibitory effects. After a 16-day treatment, the four extracts reduced M. aeruginosa by 64.1%, 59.3%, 61.9%, and 7.2% with disruption of algal photosynthesis and protein synthesis and reduction of algal toxin.