Twenty-four early-lactation primiparous and multiparous Holstein cows, beginning 5 weeks postpartum, were used for 4 weeks to investigate the effects of feeding rumen-protected choline (RPC) or vitamin E on milk yield, dry matter intake (DMI), blood metabolites and plasma enzymes. Cows were randomly assigned to one of the following treatments: no supplement (control), 90 g/day of RPC, or 4400 IU/day of vitamin E. Treatments did not affect milk yield, DMI, plasma glucose, non-esterified fatty acids, blood urea nitrogen, aspartate aminotransferase or total bilirubin, whereas feeding RPC affected cholesterol, plasma albumin, and alkaline phosphatase (ALP). Feeding vitamin E affected triglyceride, cholesterol, β-hydroxy butyric acid, gamma-glutamyl transferase and alanine aminotransferase, and highly affected plasma albumin and ALP. There was a tendency for vitamin E supplementation to increase plasma total protein concentration. The results of this study suggest that supplemental vitamin E may improve liver function in dairy cows in early lactation.

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Some materials, due to their inherent properties, can be used as shock and wave absorbers. These materials include foam and porous materials, in this study, specimens were made by casting aluminum on porous mineral pumice. Which can replace aluminum foam in some applications with lesser cost, at first, the material is compared with aluminum foam using compression test and quasi-static loading diagram. Which compares the diagrams of these two materials showing the similarity of their behavior in quasi-static loading. Initially, the elastic bending of the walls causes an elastic region in the stress-strain curve of the material. Then, the plastic collapsing of the cells forms a large and relatively smooth region along the elastic and after the plastic collapse of the cells, the area known as foam densification begins where the density of the foam closer to the density of its constituent material causes a sudden increase in the stress level in the specimen. These steps have also been seen in the quasi-static loading of aluminum foam. Then, by using numerical simulations with ANSYS AUTODYN and the shock tube test the ability of these specimens were investigated to reduce the shock wave. The behavior of the material in this case is also very similar to the results of previous studies on aluminum foam.

In this paper, the vibrations and dynamic response of an orthotropic thin-walled composite cylindrical shell with epoxy graphite layers reinforced with carbon nanotubes under heat shock and heat field loading are investigated. the carbon nanotubes were uniformly distributed along the thickness of the composite layer. The problem is that at first there is a temperature change due to the thermal field in the cylinder and the cylinder is coincident with the thermal field, then the surface temperature of the cylinder rises abruptly. Partial derivative equations of motion are coupled to heat equations. The differential quadrature method (DQM) is used to solve the equations. In this study, the effects of length, temperature, thickness and radius parameters on the natural frequencies and mid-layer displacement are investigated. The results show that increasing the outside temperature reduces the natural frequency and increases the displacement of the system. Radial displacement results were also compared with previous studies and were found to be in good agreement with previous literature. Increasing the percentage of carbon nanotubes also increased the natural frequency of the system and decreased the mobility of the middle layer.

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