How insects survive the cold: molecular mechanisms - a review

Insects vary considerably in their ability to survive low temperatures. The tractability of these organisms to experimentation has lead to considerable physiology-based work investigating both the variability between species and the actual mechanisms themselves. This has highlighted a range of strategies including freeze tolerance, freeze avoidance, protective dehydration and rapid cold hardening, which are often associated with the production of specific chemicals such as antifreezes and polyol cryoprotectants. But we are still far from identifying the critical elements behind over-wintering success and how some species can regularly survive temperatures below -20°C. Molecular biology is the most recent tool to be added to the insect physiologist’s armoury. With the public availability of the genome sequence of model insects such as Drosophila and the production of custom-made molecular resources, such as EST libraries and microarrays, we are now in a position to start dissecting the molecular mechanisms behind some of these well-characterised physiological responses. This review aims to provide a state of the art snapshot of the molecular work currently being conducted into insect cold tolerance and the very interesting preliminary results from such studies, which provide great promise for the future

Evaluating complementary currencies: from the assessment of multiple social qualities to the discovery of a unique monetary sociality

The phenomenon of complementary currencies has experienced in recent years a significant evolution both in terms of the sheer number of initiatives and in terms of their ability to attract the attention of academia, politics and media. The spread of these experiments and the increasing involvement of public institutions have led to a growing demand for evaluation procedures specifically targeted at CCs, both as economic experiments and as public policy initiatives. The task of evaluation confronts the peculiar multidimensional character of complementary currencies. One of the traits that is commonly recognized as a characteristic of CCs is indeed the presence, alongside more strictly economic dimensions, of multiple social dimensions and aims. Some evaluation models therefore attempt to measure—through the identification of multiple variables, and of corresponding indicators—the impacts of complementary currencies in terms of a wide range of expected social or economic objectives. This paper intends to question the sufficiency of similar approaches. We will argue that those approaches risk to overshadow a peculiar form of sociality which may emerge particularly in certain types of complementary currency experiments. The paper highlights the significance of this sociality and the relevance of its analysis for the advancement of evaluation practices in the field of monetary innovation