High-fidelity intracranial electrode arrays for recording and stimulating brain activity have facilitated major advances in the treatment of neurological conditions over the past decade. Traditional arrays require direct implantation into the brain via open craniotomy, which can lead to inflammatory tissue responses, necessitating development of minimally invasive approaches that avoid brain trauma. Here we demonstrate the feasibility of chronically recording brain activity from within a vein using a passive stent-electrode recording array (stentrode). We achieved implantation into a superficial cortical vein overlying the motor cortex via catheter angiography and demonstrate neural recordings in freely moving sheep for up to 190 d. Spectral content and bandwidth of vascular electrocorticography were comparable to those of recordings from epidural surface arrays. Venous internal lumen patency was maintained for the duration of implantation. Stentrodes may have wide ranging applications as a neural interface for treatment of a range of neurological conditions.

The Defense Advanced Research Projects Agency (DARPA) has funded innovative scientific research and technology developments in the field of brain-computer interfaces (BCI) since the 1970s. This review highlights some of DARPA's major advances in the field of BCI, particularly those made in recent years. Two broad categories of DARPA programs are presented with respect to the ultimate goals of supporting the nation's warfighters: (1) BCI efforts aimed at restoring neural and/or behavioral function, and (2) BCI efforts aimed at improving human training and performance. The programs discussed are synergistic and complementary to one another, and, moreover, promote interdisciplinary collaborations among researchers, engineers, and clinicians. Finally, this review includes a summary of some of the remaining challenges for the field of BCI, as well as the goals of new DARPA efforts in this domain.

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Monthly inflow and outflow data were collected from three wet detention ponds in Wilmington, North Carolina, for a 29-mo period. Two ponds drained urban areas consisting primarily of residential, mixed services, and retail usage, while the third mainly drained residential and golf course areas. One of the urban ponds achieved significant reductions in total nitrogen, nitrate, ammonium, total phosphorus, orthophosphate, and fecal coliform bacterial counts. This pond was characterized by a high length to width ratio, with most inputs directed into the upper area, and extensive coverage by a diverse community of aquatic macrophyte vegetation. The second urban pond achieved significant reductions in turbidity and fecal coliform bacterial counts, but there were no significant differences between inflowing and outflowing water nutrient concentrations. There were substantial suburban runoff inputs entering the mid- and lower-pond areas that short-circuited pollutant removal contact time. The golf course pond showed significant increases in nitrate, ammonium, total phosphorus, and orthophosphate in the outflow relative to the inflow, probably as a result of course fertilization. However, nutrient concentrations in the outflow water were low compared with discharges from a selection of other area golf courses, possibly a result of the outflow passing through a wooded wetland following pond discharge. To achieve good reduction in a variety of pollutants, wet pond design should include maximizing the contact time of inflowing water with rooted vegetation and organic sediments. This can be achieved through a physical pond design that provides a high length to width ratio, and planting of native macrophyte species.

Water quality investigations were conducted at five golf courses in southeastern North Carolina to determine levels of pollutants contributed by the courses to adjacent coastal streams. In general, nitrate levels were greater in streams leaving the courses compared with streams entering the courses, but concentrations varied considerably among courses. Ammonium concentrations increased in passage through most of the courses. Orthophosphate concentrations were elevated on midcourse sites on two courses, but were low in the outflow water except at one course. The golf courses studied were not significant sources of fecal coliform bacteria to nearby waterways; in fact, passage through some courses served to reduce coliform loads entering from upstream suburbs. Recent rainfall and fertilization application influenced outfall nitrate concentrations only at some courses. Landscape management practices appeared to play a critical role in determining nutrient concentrations in the outfall and at midcourse sites. Nutrient addition bioassay experiments conducted in one of the coastal creeks receiving golf course effluent demonstrated that nutrient concentrations as low as 50 to 100 µg nitrate N L−1 were capable of causing significant phytoplankton biomass increases. Nitrate levels in the outflow streams were at or above concentrations causing significant increases in phytoplankton biomass in our bioassay experiments. These coastal creeks host spring and summer algal blooms; thus, some golf course discharge nutrient concentrations are at levels great enough to contribute to eutrophication problems in estuarine waters. Vegetated buffer zones, wet detention ponds, and wooded wetland areas led to considerably lower nutrient output than sites lacking such management practices and should be used whenever possible to protect nutrient‐sensitive receiving waters.