Pacific herring, Clupea pallasi, recruitment in the Bering Sea and north-east Pacific Ocean, II: relationships to environmental variables and implications for forecasting

Previous studies have shown that Pacific herring populations in the Bering Sea and north-east Pacific Ocean can be grouped based on similar recruitment time series. The scale of these groups suggests large-scale influence on recruitment fluctuations from the environment. Recruitment time series from 14 populations were analysed to determine links to various environmental variables and to develop recruitment forecasting models using a Ricker-type environmentally dependent spawner–recruit model. The environmental variables used for this investigation included monthly time series of the following: southern oscillation index, North Pacific pressure index, sea surface temperatures, air temperatures, coastal upwelling indices, Bering Sea wind, Bering Sea ice cover, and Bering Sea bottom temperatures. Exploratory correlation analysis was used for focusing the time period examined for each environmental variable. Candidate models for forecasting herring recruitment were selected by the ordinary and recent cross-validation prediction errors. Results indicated that forecasting models using air and sea surface temperature data lagged to the year of spawning generally produced the best forecasting models. Multiple environmental variables showed marked improvements in prediction over single-environmental-variable models.     

Simulating landscape catena effects in no-till dryland agroecosystems using GPFARM

This study evaluated the site-specific applicability and efficacy of the GPFARM decision support system (DSS) based on underlying simulation model performance for dry mass grain yield, crop residue, total soil profile water content, and total soil profile residual NO₃-N across a landscape catena for dryland no-till experimental locations in eastern Colorado. Relative error of simulated mean, normalized objective function (root mean square error divided by the observed mean), and index of agreement evaluation statistics were calculated to compare modeled results to observed data. A one-way, fixed-effect ANOVA was also performed to determine differences among experimental locations and summit, sideslope, and toeslope landscape positions. GPFARM simulations matched observed data trends, with the model correctly distinguishing variations between the summit and toeslope landscape positions. In addition, experimental observations and GPFARM simulations both indicated that the toeslope landscape position was the most productive for grain yield and also exhibited higher amounts of crop residue, total soil profile water content, and total soil residual NO₃-N. The GPFARM crop model performed adequately but was inconsistent in simulating winter wheat, corn, and sorghum dry mass grain yield. GPFARM performance in simulating crop residue was poorer than for crop grain yield. GPFARM predicted mean total soil profile water content was generally within ±20% of the observed mean across locations and landscape positions, with the model somewhat biased towards overpredicting total soil profile water content at the summit and sideslope landscape positions. Total soil profile residual NO₃-N was underpredicted by GPFARM across all locations and landscape positions by an average of 30%. Although GPFARM appears to have reasonably simulated long-term output responses across a landscape catena for the eastern Colorado experimental locations (especially given the simplifying assumptions in many of the GPFARM simulation components and the inherent variability present at the experimental plot level), different interpretations of GPFARM performance can be made depending on the evaluation statistic of interest. Furthermore, the model cannot fully account for water and chemical movement across the landscape catena; simulation results suggest that addition of a spatially-distributed routing component should offer improvements in GPFARM prediction accuracy across a catena where surface runoff or lateral subsurface flow is occurring.     

Inhibition of Biofilm Formation by Modified Oxylipins from the Shipworm Symbiont Teredinibacter turnerae

The bioactivity-guided purification of the culture broth of the shipworm endosymbiont Teredinibacter turnerae strain 991H.S.0a.06 yielded a new fatty acid, turneroic acid (1), and two previously described oxylipins (2–3). Turneroic acid (1) is an 18-carbon fatty acid decorated by a hydroxy group and an epoxide ring. Compounds 1–3 inhibited bacterial biofilm formation in Staphylococcus epidermidis, while only 3 showed antimicrobial activity against planktonic S. epidermidis. Comparison of the bioactivity of 1–3 with structurally related compounds indicated the importance of the epoxide moiety for selective and potent biofilm inhibition.     

Nd:YAG Laser Treatment of a Vestibulovaginal Varicosity in a 15-Year-Old Pregnant Mare

A 15-year-old, pregnant Dutch Warmblood mare was exhibiting intermittent hemorrhage secondary to a large vestibulovaginal varicosity. The vessel was reduced with transendoscopic Nd:YAG laser photocoagulation. This technique is minimally invasive compared with traditional surgical ligation, and significantly decreases the risk of severe hemorrhage, especially with advancing pregnancy. One laser treatment resulted in complete reduction in vessel size and allowed the pregnancy to continue to term without incident or further vaginal hemorrhage.     

A Genome-Wide Association Study for Morphometric Traits in Quarter Horse

A genome-wide association study for morphometric traits was conducted in 184 Quarter Horses, 120 from a racing population, and 64 from a cutting population, which were genotyped using the Illumina EquineSNP50 chip. Association analysis was performed with 42,058 single-nucleotide polymorphisms (SNPs) (after quality control) using Qxpak5 software. The following traits were measured: weight (W), rump length (RL), and body length (BL). These morphometric traits are important for the best performance in race and cutting events. For weight, three SNPs associated (P < .0001) were found on chromosomes (Equus caballus autosomes [ECA]) 2 and 3. For rump length, eight SNPs associated (P < .0001) were found on ECA 2, 3, 6, 7, 9, 21, and 26. On ECA 3 and ECA 8, two SNPs were associated (P < .0001) with body length. So, a total of 13 important chromosomal regions were identified with Q values of 0.53 (SNPs for W), 0.40 (SNPs for RL), and 0.99 (SNPs for BL). Positional and functional candidate genes emerging from this study were WWOX and AAVPR1A. Further studies are required to confirm these associations in other populations.