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Intensive water hammer can cause pipe collapse in long-distance water transfer pipeline systems. Pressure control facilities like surge tank have been widely applied to help control the extensive pressure fluctuations. In our previous work, a kind of spring self-adaptive auxiliary control (SAC) system was proposed and demonstrated to have a significant improvement on pressure control capacity of a normal surge tank. In this study, an additional solution, a partially expanded structural treatment, was introduced to a conventional SAC surge tank to further improve its functional ability. The 1D numerical model was established in our in-house codes on FORTRAN. The dominant geometrical parameters were identified and quantitatively studied with various cases. According to the effects of the geometrical parameters, a designing protocol for searching the optimal solutions of partially expanded SAC surge tank was concluded. With the obtained optimal solutions, the proposed partially expanded SAC surge tank can perform a much better pressure control performance dealing with valve closure induced water hammer, compared with a conventional SAC surge tank as well as a normal surge tank.

Microfluidic microparticle manipulation is currently widely used in environmental, bio-chemical, and medical applications. Previously we proposed a straight microchannel with additional triangular cavity arrays to manipulate microparticles with inertial microfluidic forces, and experimentally explored the performances within different viscoelastic fluids. However, the mechanism remained poorly understood, which limited the exploration of the optimal design and standard operation strategies. In this study, we built a simple but robust numerical model to reveal the mechanisms of microparticle lateral migration in such microchannels. The numerical model was validated by our experimental results with good agreement. Furthermore, the force fields under different viscoelastic fluids and flow rates were carried out for quantitative analysis. The mechanism of microparticle lateral migration was revealed and is discussed regarding the dominant microfluidic forces, including drag force, inertial lift force, and elastic force. The findings of this study can help to better understand the different performances of microparticle migration under different fluid environments and complex boundary conditions.

The use of supplementary cementitious materials (SCMs) to improve concrete performance has increased around the world in recent decades. Engineering practices demand a unified model for SCMs to predict and optimise the performance of blended concrete.DuCOM-COM3 is a multi-chemo-physical and multiscale analysis platform that can trace the whole-life behaviour and performance of reinforced concrete structures. However, the intrinsic heterogeneity and variability of SCMs present great challenges to the modelling of blended concrete. This paper first reviews the challenges and difficulties of current models of blended concrete. A multiphase modelling scheme based on DuCOM-COM3 analysis platform is introduced to consider different SCMs. Using the modelling scheme, a research road map for blended concrete modelling is introduced for future study. It is hoped that the roadmap will help to reveal the mechanism of SCM reactions and their effect on concrete performance.

Abstract Background Paddy soil dissolved organic matter (DOM) represents a major hotspot for soil biogeochemistry, yet we know little about its chemodiversity let alone the microbial community that shapes it. Here, we leveraged ultrahigh-resolution mass spectrometry, amplicon, and metagenomic sequencing to characterize the molecular distribution of DOM and the taxonomic and functional microbial diversity in paddy soils across China. We hypothesized that variances in microbial community significantly associate with changes in soil DOM molecular composition. Results We report that both microbial and DOM profiles revealed geographic patterns that were associated with variation in mean monthly precipitation, mean annual temperature, and pH. DOM molecular diversity was significantly correlated with microbial taxonomic diversity. An increase in DOM molecules categorized as peptides, carbohydrates, and unsaturated aliphatics, and a decrease in those belonging to polyphenolics and polycyclic aromatics, significantly correlated with proportional changes in some of the microbial taxa, such as Syntrophobacterales, Thermoleophilia, Geobacter, Spirochaeta, Gaiella, and Defluviicoccus. DOM composition was also associated with the relative abundances of the microbial metabolic pathways, such as anaerobic carbon fixation, glycolysis, lignolysis, fermentation, and methanogenesis. Conclusions Our study demonstrates the continental-scale distribution of DOM is significantly correlated with the taxonomic profile and metabolic potential of the rice paddy microbiome. Abiotic factors that have a distinct effect on community structure can also influence the chemodiversity of DOM and vice versa. Deciphering these associations and the underlying mechanisms can precipitate understanding of the complex ecology of paddy soils, as well as help assess the effects of human activities on biogeochemistry and greenhouse gas emissions in paddy soils.

This study aimed to investigate the effects of dietary Bovine lactoferricin (LFcinB) on the growth performance and non-specific immunity in Macrobrachium rosenbergii. Five experimental diets were 1.0‰ Bovine lactoferricin (LCB1); 1.5‰ Bovine lactoferricin (LCB1.5); 2.0‰ Bovine lactoferricin (LCB2); 2.5‰ Bovine lactoferricin (LCB2.5); the control group, basal diet without Bovine lactoferricin. A total of 600 prawns were randomly assigned to 5 groups in triplicate in 15 tanks for an 8-week feeding trial. The results showed the final weight, weight gain rate, specific growth rate and survival rate of prawns in the treatment groups were significantly improved versus the control (P < 0.05). The feed conversion ratio was reduced significantly in treatment groups compared to the control (P < 0.05). Compared with the control, alkaline phosphatase (AKP), acid phosphatase (ACP), lysozyme (LZM), catalase (CAT), superoxide dismutase (SOD) activities in the hepatopancreas of the treatment groups were significantly enhanced, and malondialdehyde (MDA) content was reduced significantly (P < 0.05). Compared with the control, the relative expression levels of AKP, ACP, LZM, CAT, SOD, Hsp70, peroxiredoxin-5, Toll, dorsal and relish genes were significantly higher among treatment groups, except for the AKP gene in the LCB1 group and the Hsp70 gene in the LCB1.5 group (P < 0.05). Compared with the control, the relative expression levels of TOR, 4E-BP, eIF4E1α and eIF4E2 genes were significantly enhanced in the LCB1.5 group (P < 0.05). When resistance against Vibrio parahaemolyticus in prawn is considered, higher doses of Bovine lactoferricin show better antibacterial ability. The present study indicated that dietary Bovine lactoferricin could significantly improve the growth performance and improve the antioxidative status of M. rosenbergii. The suitable addition level is 1.5 g/kg. LFcinB has great potential as a new feed additive without the threat of drug resistance., Competing Interests: Declaration of competing interest No conflict of interest., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The present study evaluated the growth performance, digestive enzyme activity, non-specific immunity, immunity and growth genes in Penaeus vannamei fed diets supplemented with Bovine lactoferricin (the basal diet without Bovine lactoferricin, the control; 1.0‰ Bovine lactoferricin，LCB1; 1.5‰ Bovine lactoferricin，LCB1.5; 2.0‰ Bovine lactoferricin, LCB2; 2.5‰ Bovine lactoferricin, LCB2.5) for 56 days. The feeding trial showed that the final weight, weight gain rate, and specific growth rate of the shrimp were improved significantly, while the feed conversion ratio was reduced significantly in the LCB1.5 group compared to the control (P < 0.05). The challenge test of Vibrio parahaemolyticus showed that the cumulative mortalities of shrimp in the LCB1.5, LCB2 and LCB2.5 groups were significantly lower than that in the control (P < 0.05). Compared with the control, Lipase and Trypsin activities in the hepatopancreas of LCB1.5 and LCB2 groups were significantly enhanced (P < 0.05). Compared with the control, alkaline phosphatase, acid phosphatase activities in the hepatopancreas and the relative expression levels of Relish, Toll, JAK, STAT, TOR, Raptor, 4E-BP, eIF4E1α, eIF4E2 genes in the hepatopancreas of LCB1.5, LCB2 and LCB2.5 groups were all significantly enhanced (P < 0.05). These results suggested that dietary Bovine lactoferricin could improve the growth performance, digestive capacity and immune responses of shrimp. When resistance against Vibrio parahaemolyticus in shrimp is considered, high dosage of Bovine lactoferricin showed a better effect than low dosage of Bovine lactoferricin. However, high dosage of Bovine lactoferricin can have a negative impact on the growth performance of shrimp. Considering collectively the above, Bovine lactoferricin could improve the growth performance, digestive enzymes activities, immune responses and disease resistance of P. vannamei., (Copyright © 2022 Elsevier Ltd. All rights reserved.)