The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)

Interactions among water content, rapid (nonequilibrium) cooling to -196 degrees C, and survival of embryonic axes of Aesculus hippocastanum L. seeds.

This study investigated the interactions among water content, rapid (nonequilibrium) cooling to -196 degrees C using isopentane or subcooled nitrogen, and survival of embryonic axes of Aesculus hippocastanum. Average cooling rates in either cryogen did not exceed 60 degrees C s(-1) for axes containing more than 1.0 g H(2)O g(-1)dw (g g(-1)). Partial dehydration below 0.5 g gg(-1) facilitated faster cooling, averaging about 200 and 580 degrees C s(-1) in subcooled nitrogen and isopentane, respectively. The combination of partial drying and rapid cooling led to increased survival and reduced cellular damage in axes. Electrolyte leakage was 10-fold higher from fully hydrated axes cooled in either cryogen than from control axes that were not cooled. Drying of axes to 0.5 g g(-1), reduced electrolyte leakage of cryopreserved axes to levels similar to those of control material. Axis survival was assayed by germination in vitro. Axes with water contents greater than 1.0 g g(-1), did not survive cryogenic cooling. Between 1.0 and 0.75 g g(-1), axes survived cryogenic exposure but developed abnormally. The proportion of axes developing normally after being cooled in isopentane increased with increasing dehydration below 0.75 g g(-1), reaching a maximum between 0.5 and 0.25 g g(-1) after being cooled at > or =300 degrees C s(-1). Cooling rates attained in subcooled nitrogen did not exceed 250 degrees C s(-1), and normal development of axes was observed only at < or =0.4 g g(-1). These results support the hypothesis that rapid cooling enhances the feasibility of cryopreservation of desiccation-sensitive embryonic axes by increasing the upper limit of allowable water contents and overall survival.[1]


WikiGenes - Universities