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In order to match the color difference between black asphalt mixture and light-colored cement grouting paste in semiflexible pavement, carbon black (CB) with four mass ratios (i.e., 2, 4, 6, and 8%) was incorporated into a rapid-hardening cement grouting paste. The fluidity, color difference, spectrum reflectance, thermal conductivity, and flexural and compressive strength of the aforementioned cement pastes were experimentally investigated. The results show that the mass ratios of the component in cement paste could ensure the good fluidity of cement grouting paste. Three parameters such as thermal conductivity, flexural strength, and compressive strength all reduced, compared with control paste. However, the compressive strength of the 8% CB paste was still much higher than that of the asphalt mixture. According to the color difference results, CB significantly improved the black color of cement paste, of which the black color of the asphalt mixture was between that of 6 and 8% CB cement paste. Besides, the spectrum reflectance of all the pastes reduced, especially the average reflectance of 2% CB cement paste was 51.7% lower than that of control paste. The findings in this study are expected to help design more advanced cement grouting materials to improve the optical and mechanical performances of semiflexible asphalt pavement.

Simple Summary: Eggshell quality is an important factor affecting the egg production industry. Organic trace elements have been proven to delay egg spoilage. However, the potential mechanism of organic trace elements is still unclear. This study investigated the effects of different doses of organic trace elements supplementation in the diet on eggshell quality in the late phase of the laying hens. The results showed that 30–40% organic trace elements supplementation improved the eggshell quality via regulating enzymes and genes of eggshell formation. The quality of eggshells is critical to the egg production industry. The addition of trace elements has been shown to be involved in eggshell formation. Organic trace elements have been found to have higher biological availability than inorganic trace elements. However, the effects of organic trace elements additive doses on eggshell quality during the laying period of commercial laying hens required further investigation. This experiment aims to explore the potential mechanisms of different doses of organic trace elements replacing inorganic elements to remodel the eggshell quality of egg-laying hens during the laying period. A total of 360 healthy hens (Lohmann Pink, 45-week-old) were randomly divided into four treatments, with six replications per treatment and 15 birds per replication. The dietary treatments included a basal diet supplemented with inorganic iron, copper, zinc and manganese at commercial levels (CON), a basal diet supplemented with organic iron, copper, zinc and manganese at 20% commercial levels (LOT), a basal diet supplemented with organic iron, copper, zinc and manganese at 30% commercial levels (MOT), and a basal diet supplemented with organic iron, copper, zinc and manganese at 40% commercial levels (HOT). The trial lasted for 8 weeks. The results of the experiment showed that the replacement of organic trace elements did not significantly affect the production performance of laying hens (p > 0.05). Compared with inorganic trace elements, the MOT and HOT groups improved the structure of the eggshells, enhanced the hardness and thickness of the eggshells, increased the Haugh unit of the eggs, reduced the proportion of the mammillary layer in the eggshell, and increased the proportion of the palisade layer (p < 0.05). In addition, the MOT and HOT groups also increased the enzyme activity related to carbonate transport in the blood, the expression of uterine shell gland-related genes (CA2, OC116, and OCX32), and the calcium and phosphorus content in the eggshells (p < 0.05). We also found that the MOT group effectively reduced element discharge in the feces and enhanced the transportation of iron (p < 0.05). In conclusion, dietary supplementation with 30–40% organic micronutrients were able to improve eggshell quality in aged laying hens by modulating the activity of serum carbonate transport-related enzymes and the expression of eggshell deposition-related genes. [ABSTRACT FROM AUTHOR]

Rhynocoris fuscipes and Arma chinensis are two important predatory natural enemies that can control Spodoptera litura. To investigate cannibalism and intraguild predation (IGP) between these two predatory bugs, experiments were conducted to evaluate R. fuscipes and A. chinensis under laboratory conditions. The results showed that the cannibalism effects of both species increased with insect instar, and the cannibalism effect of R. fuscipes was more severe than that of A. chinensis. Both predatory bugs had an IGP effect at all nymphal and adult stages, but few eggs were preyed upon. The survival rate of R. fuscipes was higher than that of A. chinensis at each developmental stage, especially the survival rate of 1st instar nymphs of R. fuscipes was significantly higher than that of 1st instar nymphs of A. chinensis. When S. litura was provided as prey, the IGP effects of R. fuscipes and A. chinensis at different stages were significantly reduced. These results indicated that R. fuscipes was an intraguild predator (IG-predator) and A. chinensis was an intraguild prey (IG-prey) . The combined predation effect of two predators on S. litura was significantly higher than that of a single predator. [ABSTRACT FROM AUTHOR]

To screen for effective Myzus persicae control agents that are safe for Rhynocoris fuscipes in tobacco fields, the toxicity of nine common insecticides against M. persicae and 2nd instar nymphs of R. fuscipes was tested using the leaf-dip method and the insecticide residual in glass tube method. Drug safety for R. fuscipes was evaluated, and plot experiments were conducted in tobacco fields. The results showed that the LC50 of the nine agents for M. persicae were acetamidine 44.311 mg/L, fludizonitrile 46.696 mg/L, rotenone 71.499 mg/L, eucalyptol 77.538 mg/L, dipropirenol 139.697 mg/L, pyrazidone 175.142 mg/L, pyrethrin 427.589 mg/L, veratrine 322.856 mg/L, and metarium anisopliae (CQMa421)205.921 cfu/mL, respectively. The highest and lowest LC50 for the 2nd instar nymphs of R. fuscipes were rotenone 139.596 mg/L and metartaria anisopliae(CQMa421)1 599.419 cfu/mL. The analysis of safety coefficient and benefit-to-harm toxicity ratio suggested that eucalyptol, metarhizium anisopliae, acetamiprid, pyrzidone, and metarhizium anisopliae(CQMa421)had good control effects on M. persicae, and had less toxicity on the 2nd instar nymphs of R. fuscipes. The plot experiments showed that the control effects of eucalyptol, pyrzidone, and metartaria anisopliae (CQMa421) combined with R. fuscipes were 93.14%, 91.22%, and 91.00%, respectively, which were better than using eucalyptol or R. fuscipes alone. [ABSTRACT FROM AUTHOR]