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This study looks at wall partition panels with hollow core wood elements and gypsum board as protection in fire conditions. In addition to our previous research, this study on wall partitions considers the effect of steel screws in the assembly of the elements, as well as the filling of the cavity with insulating material. The goal of this work is to calculate the fire resistance time and compare the results using different numerical models. The discussion of the results analyzes the effect of steel screws and the introduction of insulating material inside the cavities. The steel screws are verified with and without threads. The numerical models are based on the finite element method, using thermal and transient analysis with nonlinear materials. The thermal insulation criterion for measuring fire resistance is referenced by the EN 1363-1:2020 standard. The steel screws allow more heat to be concentrated and, therefore, distribute it throughout the wooden wall partition members. Based on the results obtained, the use of steel screws reduces fire resistance by 71.75 min, regardless of whether the wall partition is filled with or without insulating material. [ABSTRACT FROM AUTHOR]

The present study is focused on wall panels exposed to fire, with the construction building elements we used being made of wood and gypsum board materials. This type of configuration forms hollow core wood due to the constructive process. The aim is to present a numerical study to approach the calculation of the temperature inside hollow core wood elements and measure their fire resistance. The temperature evolution inside the cavities will be obtained with recourses to obtain the heat effect by convection and radiation through the wall elements. A numerical model, previously validated by the authors, will be used to carry out this process. The methodology includes the use of the finite element method in thermal and transient analysis with nonlinear materials to calculate temperature. To measure the fire resistance of the constructive model, the thermal insulation criterion, defined by the EN 1363-1:2020 standard, will be applied. Different results will be presented to discuss and ensure the verification of these fire-resistant elements. [ABSTRACT FROM AUTHOR]

Liver resection is a suitable option for the treatment of certain hepatic conditions, particularly hepatocarcinomas, in patients with cirrhosis. However, this disease impairs liver regeneration, which increases the risk of liver failure and postoperative death. Supportive treatments for regeneration of the remaining liver may be useful for the recovery of these patients. We demonstrated that nutritional hepatotrophic factors (NHF) is an effective regenerative stimulus for cirrhotic livers in rats subjected to partial hepatectomy (PH). The rats with thioacetamide-induced cirrhosis were subjected to PH, and they were divided into 2 groups. One group received intraperitoneal administration of NHF, and the other group received saline solution. After 12 days, biometric data, collagen content, hepatocyte regeneration (proliferation cell nuclear antigen immunochemistry), and profibrotic gene expression (Collagen-α1, matrix metalloproteinase 2, tissue inhibitor of metalloproteinase 1, and transforming growth factor beta 1) were assessed. The results indicated that the rats treated with NHF after PH had an increased liver size, a reduced amount of collagen, and a higher hepatocyte proliferation index compared with the rats that underwent PH alone. In addition, collagen-α1 gene expression was decreased in the NHF-treated rats. Thus, postoperative improvement in the liver morphology following NHF treatment may cause a significant decrease in the risk of liver failure and mortality after hepatic resection. [ABSTRACT FROM PUBLISHER]