Lateral Buckling of Prismatic Members About an Imposed Axis of Rotation

This paper deals with the lateral buckling of prismatic members whose position of the axis of rotation is imposed by the conditions of lateral support. As a function of the type of connection with the lateral support, the rotation may be free or hindered (elastic end restraint). This may concern, for instance, the case of a purlin stabilized by a roof structure or of a column stabilized by an external cladding or by another type of efficient continuous bracing. Usually, the check of this type of instability is complex and leads to sophisticated and tedious computations. In order to avoid this inconvenience, approached solutions are often used. One of the most frequently used consists in calculating the compressed member as being fictitiously separated, submitted to lateral buckling in an elastic medium. The stiffness of this fictitious member is taken equal to its stiffness in lateral bending. The present paper proposes an improved behaviour model of members submitted to lateral buckling through which the stiffness of the fictitious member is determined by taking into account the torsional stiffness of the whole transverse section of the profile

A Non Linear Design Model for Continuous Multi-span Light Gauge Sheeting and Members

The calculation of profiled sheeting and members by using the post-critical stage in which a plastic hinge is originated at the internal support is possible provided that the relationships between the support moment, reaction and hinge rotation are known. There are two alternative procedures of testing for obtaining these data: double-span test or internal support test. In the second one, instead of a global behaviour, only the local relationships between the three above characteristics are determined. When calculating with the model proposed in Eurocode 3, Part 1.3, the above two different test procedures do not lead to close enough results. The present paper is aimed at both explaining the reasons of these differences and proposing consequently an improved approach to the behaviour at the internal support

Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field