Survey onYersinia Enterocolitica and related bacteria in shellfish

Results from examining shellfish collected from ‘safe’ (2–34Escherichia coli/100 mL) and ‘unsafe’ (> 34E. coli/100 mL) waters for the presence ofYersinia enterocolitica and related bacteria are reported. The recovery of these microorganisms was low in bivalve mollusks destined for food consumption, high in those derived from prohibited areas. No human pathogenic bio-serogroup f Yersinia was found during the entire survey.     

Photochlorination of organics by aqueous Cl− codissolved with anionic NO x Emphasis>/−

The dissipation of chemical elements from ash basin effluent was determined by use of neutron activation analysis of sediment, water, plant, invertebrate, and vertebrate samples taken from successive sites through the drainage system. Samples were tested for concentrations of 40 elements for a 12 mo period. Three different modes of dissipation were found. The major mechanism for removal of chemical elements from effluent was sedimentation into the benthic sediment. All biota had greater concentrations of chemicals than did water, with invertebrates having slightly higher levels than did plants and vertebrates. Ten elements were more concentrated in at least one biotic group than in the sediment. Concentrations of six elements in the drainage system exceeded the EPA recommended limits for surface waters. The observed modes of dissipation in this aquatic system emphasize the necessity for stable biotic communities present to permit cycling of chemical elements.     

Nature and domestic life in the Valle del Cuñapirú (Misiones, Argentina): Reflections on Mbyá-Guaraní ethnoecology

Through the ethnographic record of the subsistence activities partially or completely performed in the domestic sphere in two Mbyá-Guaraní settlements in Misiones (Argentina), we outline factors important in describing the local natural environment. Data was collected through systematic observation and also through semi-structured interviews. Analysis indicates that the natural environment of the area is characterized by the indigenous community in several different ways. Thus, local people view the environment as made up of different “micro-environments,” and they consequently think of the elements that compose these “micro-environments” as having different, distinct characteristics. In the context of their daily activities, both these “micro-environments” and the elements that compose them are regarded as resources, in that they are viewed in terms of what is in them relevant to the subsistence of these groups in the rainforest. It is the intention of this study to initiate the systematic recording and processing of information on how these indigenous communities know and manage the natural resources available to them in their daily life.     

An isomorphous heavy-atom derivative of crystaline formylmethionine transfer RNA

An isomorphous osmium derivative of crystalline yeast initiator transfer RNA has been prepared and interpreted to 6-angstrom resolution. The coordinates of the heavy atoms have been determined by Patterson and "direct" methods applied to the difference coefficients of the centric projections, followed by least-squares refinement. There is one dominant site per asymmetric unit, consistent with the finding by neutron-activation analysis that there is approximately one osmium atom per molecule of transfer RNA. The osmium derivative appears to be a normal substrate for enzymatic aminoacylation.     

Correction of ADA-SCID by stem cell gene therapy combined with nonmyeloablative conditioning

Hematopoietic stem cell (HSC) gene therapy for adenosine deaminase (ADA)-deficient severe combined immunodeficiency (SCID) has shown limited clinical efficacy because of the small proportion of engrafted genetically corrected HSCs. We describe an improved protocol for gene transfer into HSCs associated with nonmyeloablative conditioning. This protocol was used in two patients for whom enzyme replacement therapy was not available, which allowed the effect of gene therapy alone to be evaluated. Sustained engraftment of engineered HSCs with differentiation into multiple lineages resulted in increased lymphocyte counts, improved immune functions (including antigen-specific responses), and lower toxic metabolites. Both patients are currently at home and clinically well, with normal growth and development. These results indicate the safety and efficacy of HSC gene therapy combined with nonmyeloablative conditioning for the treatment of SCID.     

Dorid nudibranch elaborates its own chemical defense

A biosynthetic experiment with mevalonic acid labeled with carbon-14 showed that the nudibranch Dendrodoris limbata elaborates polygodial, a sesquiterpenoid dialdehyde stored in the mantle, which constitutes its chemical defense against predators. Previously described nudibranchs drew defensive chemicals from their preys.     

Magma ascent and the pressurization of Mount Etna's volcanic system

After a period of deflation during the 1991-1993 flank eruption, Mount Etna underwent a rapid inflation. Seismicity and ground deformation show that since 1994, a huge volume of magma intruded beneath the volcano, producing from 1998 onward a series of eruptions at the summit and on the flank of the volcano. The last of these, started on 27 October 2002, is still in progress and can be considered one of the most explosive eruptions of the volcano in recent times. Here we show how geodetic data and seismic deformation, between 1994 and 2001, indicate a radial compression around an axial intrusion, consistent with a repressurization of Mount Etna's plumbing system at a depth of 6 to 15 kilometers, which triggered most of the seismicity and provoked the dilatation of the volcano and the recent explosive eruptive activity.