31 research outputs found
'Omic approaches to preventing or managing metastatic breast cancer
Early detection of metastasis-prone breast cancers and characterization of residual metastatic cancers are important in efforts to improve management of breast cancer. Applications of genome-scale molecular analysis technologies are making these complementary approaches possible by revealing molecular features uniquely associated with metastatic disease. Assays that reveal these molecular features will facilitate development of anatomic, histological and blood-based strategies that may enable detection prior to metastatic spread. Knowledge of these features also will guide development of therapeutic strategies that can be applied when metastatic disease burden is low, thereby increasing the probability of a curative response
Lawson criterion for ignition exceeded in an inertial fusion experiment
For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion
Harmful Elements in Estuarine and Coastal Systems
Estuaries and coastal zones are dynamic transitional systems which provide many economic and ecological benefits to humans, but also are an ideal habitat for other organisms as well. These areas are becoming contaminated by various anthropogenic activities due to a quick economic growth and urbanization. This chapter explores the sources, chemical speciation, sediment accumulation and removal mechanisms of the harmful elements in estuarine and coastal seawaters. It also describes the effects of toxic elements on aquatic flora and fauna. Finally, the toxic element pollution of the Venice Lagoon, a transitional water body located in the northeastern part of Italy, is discussed as a case study, by presenting the procedures adopted to measure the extent of the pollution, the impacts on organisms and the restoration activities
Cd and Mn in the Alboran Sea and adjacent North Atlantic: geochemical implications for the Mediterranean
Water flowing from the Mediterranean at the Strait of Gibraltar differs in oceanographic characteristics from inflowing Atlantic Ocean water because of the influence of climatic conditions in the Mediterranean Basin1. Little is known about how geochemical processes affect concentrations of trace metals during this transformation because there are very few accurate published data (other than some recent values2 for surface waters) for trace metals in the Mediterranean Sea, even though these are also required in assessing the impact of pollutant inputs. Here we present new data for the concentrations of dissolved Cd and Mn in the eastern Alboran Sea and the adjacent Atlantic Ocean and use them to estimate the flux of these metals through the Strait of Gibraltar. Although the Mediterranean is a source of Cd for the Atlantic Ocean, it acts as a sink for Mn entering in the inflowing Atlantic water
Upward fluxes of particulate organic matter in the deep North Pacific
The flux of particulate matter through the oceanic water column is a primary component in elemental cycling and is generally perceived as being in one direction: downward1,2. The organic matter constituting these particles is produced through photosynthesis in surface waters and either sinks directly as phytoplankton and products3,4 or undergoes various trophic transformations through the water column. A large proportion of the particulate organic matter produced in surface waters is regenerated in the euphotic zone5-7. A fraction of this organic matter, however, leaves the surface waters and settles through the water column, generally decreasing in quantity and changing in quality with increasing distance from the surface8-11. Although the net transport of organic matter must be downward to fuel the lower portions of the water column, there is also an upward component to transport. Positively buoyant particles, including lipid-rich eggs, larvae and, possibly, carcasses of deep-sea animals are examples of particles which undergo upward transport12,13. A previous attempt to quantify the upward mass flux indicated rates of 1-4% of the downward mass flux14. Here we report the first evidence that there is a significant upward flux of particulate organic matter, up to 66.7% of the concurrently measured downward flux, at two stations in the deep North Pacific. Given this magnitude, the previously ignored upward flux of such organic matter must be considered in models of carbon and nitrogen cycling in the open ocean. © 1989 Nature Publishing Group