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The direct estimation of heritability from genome-wide common variant data as implemented in the program Genome-wide Complex Trait Analysis (GCTA) has provided a means to quantify heritability attributable to all interrogated variants. We have quantified the variance in liability to disease explained by all SNPs for two phenotypically-related neurobehavioral disorders, obsessive-compulsive disorder (OCD) and Tourette Syndrome (TS), using GCTA. Our analysis yielded a heritability point estimate of 0.58 (se = 0.09, p = 5.64e-12) for TS, and 0.37 (se = 0.07, p = 1.5e-07) for OCD. In addition, we conducted multiple genomic partitioning analyses to identify genomic elements that concentrate this heritability. We examined genomic architectures of TS and OCD by chromosome, MAF bin, and functional annotations. In addition, we assessed heritability for early onset and adult onset OCD. Among other notable results, we found that SNPs with a minor allele frequency of less than 5% accounted for 21% of the TS heritability and 0% of the OCD heritability. Additionally, we identified a significant contribution to TS and OCD heritability by variants significantly associated with gene expression in two regions of the brain (parietal cortex and cerebellum) for which we had available expression quantitative trait loci (eQTLs). Finally we analyzed the genetic correlation between TS and OCD, revealing a genetic correlation of 0.41 (se = 0.15, p = 0.002). These results are very close to previous heritability estimates for TS and OCD based on twin and family studies, suggesting that very little, if any, heritability is truly missing (i.e., unassayed) from TS and OCD GWAS studies of common variation. The results also indicate that there is some genetic overlap between these two phenotypically-related neuropsychiatric disorders, but suggest that the two disorders have distinct genetic architectures.

In June 1984 a series of experiments was conducted in which the drift predictions of the Coast Guard's operational search planning computer model (CASP) were evaluated. Three satellite-tracked drift buoys and a life raft were released and tracked for two 3-day periods at the New England Shelf/Slope Front. Their movement was compared with CASP drift predictions for simulated PIW's and a life raft for two sets of environmental data: historical currents and large-scale winds versus locally measured data. For the historical data, the observed drift errors were two to four times larger than drift errors calculated by CASP. The use of on-scene environmental data improved the predictions for PIW's to near the CASP-calculated drift errors, but not for the life raft. Significant differences in the surface currents occurred over 20 nautical miles and 3 to 5 days, which were not accounted for by the historical surface current files, and therefore increased the error in the drift prediction of CASP. Keywords: Probability of detection; Ocean surface currents; Search and rescue; Fronts; Satellite-tracked buoys; Ocean circulation; Drift prediction; CASP(Computer Assisted Search Planning); Continental Shelves; Continental slope; PIW(Persons in Water).

Trajectories of five free-drifting satellite-tracked buoys released during the summer of 1979 in open water in the Beaufort Sea north of the Tuktoyaktuk Peninsula indicate a pronounced east-to-west near-surface flow along the northern Alaskan coast. The direction of the buoy movement is in general agreement with the direction of the flow in the southern portion of the Beaufort Sea Gyre as previously calculated from dynamic topography. The buoy tracks and speeds differ from the surface circulation calculated from the dynamic topography in two respects. First, the average buoy speeds (approx. 20 cm/s) were approximately 3 times larger than calculated surface currents. Second, three of the buoys moved onto the Chukchi Sea shelf near Wrangel Island instead of turning to the northwest near Point Barrow with the Beaufort Sea Gyre. The remaining two buoys stopped transmitting before reaching Point Barrow. Analysis of the available wind data suggests that the surface currents as indicated by the motions of the buoys were strongly influenced by the local wind. For surface wind speeds, or = 5 m/s the buoys moved 22 deg to the right of the wind at 3.8% of the wind speed. (Author)

During the period of 1979 through 1981 the USCG Research and Development Center conducted several experiments in which the drift predictions of the computerized Search and Rescue Planning System (SARP) were compared with the movement of satellite-tracked drift-buoys released in the Gulf Stream east of Florida. Buoy positions at specific times were used as the last known position and incident date-time-group of a simulated search and rescue (SAR) incident; subsequent buoy positions were used to test the accuracy of 24, 48, 72, 96, and 120 hour drift predictions. Of the 680 drift predictions evaluated, in only 41 cases (6.0%) was the interpolated buoy position within the SARP-predicted search area. The accuracy of the drift predictions degraded with increasing prediction time; There was no discernible difference between the predicted (forecast) and analysis (observed) wind results; If the effect of wind is not included in the drift prediction the result is a larger relative drift error; The sea current files used in the SARP drift predictions contain some systematic errors which adversely affect system performances; and The drift error factor presently in use seriously underestimates the total drift error.