Effects of a Pseudomonas H6 surfactant on rainbow trout and Ichthyophthirius multifiliis: In vivo exposure

The Pseudomonas H6 lipopeptide is a surfactant, which is able to eliminate various parasitic pathogens including the ciliate Ichthyophthirius multifiliis in vitro. This suggests an application for aquaculture purposes. However, further information on efficacy of the compound and possible immune modulation of surfactant-exposed fish should be gathered before usage at farm level is considered. We performed an in vivo infection experiment using rainbow trout fry (mean weight 4.6 g, mean length 7.6 cm) as hosts and I. multifiliis theronts as the parasitic pathogen. We compared infection level, immune gene regulation and immune cell density in gills of 1) no exposed control fish, 2) parasite exposed but untreated fish, 3) surfactant treated fish without parasite exposure, and 4) fish exposed both to parasites and surfactant. The surfactant concentration was 10 mg/L, the infection dosage 1000 theronts/fish and the exposure period 6 h. The parasite infection was recorded and samples were taken from rainbow trout gills at day 0 and 10 post-exposure. We performed an immunohistochemical investigation (detecting cells positive for MHC II, SAA, CD8, IgM, IgT and IgD) and measured the expression of genes encoding cathelidin-1, CD8, hepcidin, IFN γ, IgDs, IL-1β, IL-6 and SAA. Theront exposed fish (without surfactant treatment) became heavily infected whereas concomitant surfactant treatment (10 mg/l), along with parasite exposure, could prevent infection. A significant inflammation (upregulation of il-1β, il6, ifn γ, cathelicidin, hepcidin) was elicited in non-treated and parasite exposed fish but it was prevented by the surfactant treatment. When investigated 10 days after treatment no immune gene regulation was seen in fish exposed to surfactant only. The therapeutic effect may be due to a direct parasitical action of the surfactant, but it cannot be excluded that a modulation of the host immune reaction may influence the infection success

Genetic diversity of norovirus in Shenzhen Based on continuous surveillance from 2016 to 2022

IntroductionNorovirus is a key pathogen of acute gastroenteritis and poses a significant burden on both the economy and public health. This study focuses on continuous monitoring of norovirus in Shenzhen, China, from 2016 to 2022, aiming to analyze the epidemic characteristics and genetic diversity of norovirus in the context of global sequence data.MethodsThe study was based on data collected from local sentinel hospitals. It involved analyzing the demographic, spatial, and temporal distribution of norovirus infections. Phylogenetic analysis was conducted, and genotype dynamics were compared across geographic levels. Mutations affecting protein stability were evaluated, and recombination analysis was performed to identify critical breakpoints and fragments for norovirus.ResultsThe study found that norovirus primarily infected infants under 3 years old, with epidemics occurring in winter and concentrated in developed districts. Phylogenetic analysis revealed both similarities and differences in the evolutionary patterns of various genotypes at different geographical levels. Mutations in the VP1 protein, based on the protein structure of GII.4_Sydney[P31], provided insights into the evolutionary trends of key genotypes. Additionally, recombination analysis identified important breakpoints and fragments for norovirus.DiscussionThe findings offer valuable insights to evolution and transmission of norovirus. These results can serve as a reference for future research, and they may aid in vaccine development efforts aimed at controlling norovirus outbreaks

The application of compaction device for highway structural layer in the road construction of Yun-Mao Highway

The compaction device for highway structural layer is the hinge connection of the end of the hydraulic breaker rod of a conventional excavator and the base of a compaction device. During operation, the steel panel of the compaction device is positioned on top of the construction area, which is then compacted by controlling the hydraulic breaker of the excavator. This device can quickly and effectively solve the common quality issues such as the insufficient compactness of the earth shoulder in highway construction projects.</jats:p

The application of simultaneous paver liquid cement sprinkling system in the road construction of Yun-Mao Highway

The simultaneous paver liquid cement sprinkling system is the combination of a conventional paver and a simultaneous liquid cement sprinkler. During operation, the cement sprinkler can be installed onto a paver with the use of connectors. When paving the stabilization aggregate mixture, this system sprinkles liquid cement on the working surface. This device can effectively solve the common quality issues such as the formation of cement isolation layer and road pollution, as a result of premature hardening of the pre-sprinkled liquid cement during road construction in high-temperature environments.</jats:p

The application of simultaneous paver liquid cement sprinkling system in the road construction of Yun-Mao Highway

The simultaneous paver liquid cement sprinkling system is the combination of a conventional paver and a simultaneous liquid cement sprinkler. During operation, the cement sprinkler can be installed onto a paver with the use of connectors. When paving the stabilization aggregate mixture, this system sprinkles liquid cement on the working surface. This device can effectively solve the common quality issues such as the formation of cement isolation layer and road pollution, as a result of premature hardening of the pre-sprinkled liquid cement during road construction in high-temperature environments

The application of compaction device for highway structural layer in the road construction of Yun-Mao Highway

The compaction device for highway structural layer is the hinge connection of the end of the hydraulic breaker rod of a conventional excavator and the base of a compaction device. During operation, the steel panel of the compaction device is positioned on top of the construction area, which is then compacted by controlling the hydraulic breaker of the excavator. This device can quickly and effectively solve the common quality issues such as the insufficient compactness of the earth shoulder in highway construction projects

Comparative Analysis of Sugar Production Cost in Guangxi and World Major Producing Countries

Guangxi is the largest sugar producing area in China and shoulders heavy responsibilities for the development of China’s sugar industry. In recent years, China’s sugar industry has been greatly impacted by the foreign low-cost sugar industry, and the planting area of ​​sugarcane has been declining. The development foundation of the sugar industry is the sugarcane seed industry. Under the impact of foreign low-price sugar, China’s sugarcane industry is under greater pressure for development, and the sugarcane seed industry shoulders more arduous responsibilities. In order to cope with international competition, the development of Guangxi's sugarcane industry urgently needs to establish a development model oriented towards improved varieties, scale and mechanization of sugarcane, so as to promote the high-quality development of Guangxi's sugarcane industry and effectively respond to the pressure of competition in the international sugarcane industry

How the Crosslinking Agent Influences the Thermal Stability of RTV Phenyl Silicone Rubber

In this work, a thermal degradation mechanism of room temperature vulcanized (RTV) phenyl silicone rubber that was vulcanized by different crosslinking agents was discussed. Firstly, RTV phenyl silicone rubber samples were prepared by curing hydroxyl-terminated polymethyldiphenylsiloxane via three crosslinking agents, namely, tetraethoxysilane (TEOS), tetrapropoxysilane (TPOS), and polysilazane. Secondly, the ablation properties of RTV phenyl silicone rubber were studied by the muffle roaster test and FT-IR. Thirdly, thermal stability of the three samples was studied by thermogravimetric (TG) analysis. Finally, to explore the thermal degradation mechanism, the RTV phenyl silicone rubber vulcanized by different crosslinking agents were characterized by TG analysis-mass spectrum (TG-MS) and pyrolysis gas chromatogram-mass spectrum (pyGC-MS). Results showed that the thermal stability of RTV phenyl silicone rubber is related to the amount of residual Si&ndash;OH groups. The residual Si&ndash;OH groups initiated the polysiloxane chain degradation via an &lsquo;unzipping&rsquo; mechanism