A mesoscale phytoplankton bloom in the polar Southern Ocean stimulated by iron fertilization

Changes in iron supply to oceanic plankton are thought to have a significant effect on concentrations of atmospheric carbon dioxide by altering rates of carbon sequestration, a theory known as the 'iron hypothesis'. For this reason, it is important to understand the response of pelagic biota to increased iron supply. Here we report the results of a mesoscale iron fertilization experiment in the polar Southern Ocean, where the potential to sequester iron-elevated algal carbon is probably greatest. Increased iron supply led to elevated phytoplankton biomass and rates of photosynthesis in surface waters, causing a large drawdown of carbon dioxide and macronutrients, and elevated dimethyl sulphide levels after 13 days. This drawdown was mostly due to the proliferation of diatom stocks. But downward export of biogenic carbon was not increased. Moreover, satellite observations of this massive bloom 30 days later, suggest that a sufficient proportion of the added iron was retained in surface waters. Our findings demonstrate that iron supply controls phytoplankton growth and community composition during summer in these polar Southern Ocean waters, but the fate of algal carbon remains unknown and depends on the interplay between the processes controlling export, remineralisation and timescales of water mass subduction.     

Identification of the familial cylindromatosis tumour-suppressor gene

Familial cylindromatosis is an autosomal dominant genetic predisposition to multiple tumours of the skin appendages. The susceptibility gene (CYLD) has previously been localized to chromosome 16q and has the genetic attributes of a tumour-suppressor gene (recessive oncogene). Here we have identified CYLD by detecting germline mutations in 21 cylindromatosis families and somatic mutations in 1 sporadic and 5 familial cylindromas. All mutations predict truncation or absence of the encoded protein. CYLD encodes three cytoskeletal-associated-protein-glycine-conserved (CAP-GLY) domains, which are found in proteins that coordinate the attachment of organelles to microtubules. CYLD also has sequence homology to the catalytic domain of ubiquitin carboxy-terminal hydrolases (UCH).     

Familial association in serum IgE levels

Summary The serum IgE levels measured by RIST correlated closely with those obtained by the single radioimmunodiffusion method. Values for husband and wife were closely related as were those between father and daughter but in contrast to previous observations no significant relationship existed between IgE levels for mother and son.Acknowledgments. The Busselton population studies, of which this paper forms part, have been supported by the University of Western Australia the Arnold Yeldham and Mary Raine Foundation, the National Heart Foundation of Australia, Royal Perth Hospital, State Health Laboratories (Western Australia), the National Health and Medical Research Council, Princess Margaret Children's Medical Research Foundation, various private donors, numerous volunteer workers, and the people of Busselton. The authors wish to personally acknowledge support from the Arnold Yeldham and Mary Raine Foundation, the National Health and Medical Research Council and the Asthma Foundation of Western Australia. We are indebted to Drs.K. J. Cullen andR. C. Godfrey for making available valuable material from the Busselton population survey.     

Thein vitro effect of various enzymes upon the mouse ascites tumor of ehrlich

Zusammenfassung Die Virulenz von Ehrlich-Ascitestumorzellen wurde durch Inkubation mit fünf Enzymenin vitro stark herabgesetzt. Zwölf andere Enzyme hatten keine Wirkung. Die morphologischen Kriterien für Zellschädigung werden erörtert.

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This work was supported in part by a grant from the American Cancer Society (Mass. Division) and in part by grants (C-3538 and CY-4018) from the U.S. Public Health Service, National Cancer Institute.