A full orthotropic bond-based peridynamic formulation for linearly elastic solids

An original full orthotropic model for in-plane linear elasticity is proposed in the micropolar peridynamic analysis framework. The analytical formulation is derived from the definition of a specific microe-lastic energy function for micropolar nonlocal lattices which allows to obtain, for the first time, an orthotropic bond-based model characterized by four independent elastic moduli. An important feature of the model is that the bond properties, i.e. the elastic constants, are continuous functions of the bond orientation in the principal material axes. The introduction of the bond shear stiffness and the definition of a bond shear deformation measure which accounts for particle’s rotation, on one hand eliminates the restriction of two independent constants that affects other bond-based orthotropic peridynamic formulations, and on the other makes the model suitable in predicting the mechanical behavior of a wide variety of Cauchy orthotropic materials undergoing homogeneous and non-homogeneous deformations. The accuracy of the proposed model in linear elasticity has been verified through simulating uniaxial extension test of a composite lamina with a central circular hole and natural frequency analyses considering different orientations of the principal material reference system

Are mycotoxins relevant to be studied in health care environments?

Project EXPOsE, nº 23222 (02/SAICT/2016)Mycotoxins are fungi metabolites produced by specific fungal genera and although the reported evidence about the health effects there is still a gap about data in health care environments. This study aimed to investigate if mycotoxins presence should be monitored in health care facilities by searching for studies that reported fungal contamination by toxigenic fungi in different health care environments. The study involved a systematic search of available information/data published on PubMed during the period of 2010 until 31st December 2018. Among the 26 papers analyzed, only in two the Aspergillus genera were not reported as the most prevalent. Additionally, other genera also with toxigenic potential were observed, namely Fusarium and Penicillium. The information gathered with this review allowed to conclude about the importance to assess mycotoxins in health care environments. Moreover, the analytical methods used should allow detecting low concentrations and multiple mycotoxins.info:eu-repo/semantics/publishedVersio