Refinement of eDNA as an early monitoring tool at the landscape-level: study design considerations.

Natural resource managers use data on the spatial range of species to guide management decisions. These data come from survey or monitoring efforts that use a wide variety of tools. Environmental DNA (eDNA) is a surveillance tool that uses genetic markers for detecting species and holds potential as a tool for large-scale monitoring programs. Two challenges of eDNA-based studies are uncertainties created by imperfect capture of eDNA in collection samples (e.g., water field samples) and imperfect detection of eDNA using molecular methods (e.g., quantitative PCR). Occurrence models can be used to address these challenges, thus we use an occurrence model to address two objectives: first, to determine how many samples were required to detect species using eDNA; second, to examine when and where to take samples. We collected water samples from three different habitat types in the Upper Mississippi River when both Bighead Carp and Silver Carp were known to be present based on telemetry detections. Each habitat type (backwater, tributary, and impoundment) was sampled during April, May, and November. Detections of eDNA for both species varied across sites and months, but were generally low, 0-19.3% of samples were positive for eDNA. Overall, we found that eDNA-based sampling holds promise to be a powerful monitoring tool for resource managers; however, limitations of eDNA-based sampling include different biological and ecological characteristics of target species such as seasonal habitat usage patterns as well as aspects of different physical environments that impact the implementation of these methods such as water temperature.

Effects of patella taping on patella position and perceived pain.

Anterior knee pain syndrome (AKPS) represents a significant challenge for the sports medicine clinician. One proposed etiological factor for AKPS is poor vastus medialis obliquus (VMO) control, resulting in lateral glide of the patella. Patella taping has been advocated to increase VMO control. The purpose of this study was to determine the effects of patella taping on patella position and perceived pain. Twelve subjects (age = 29 +/- 9 yr; weight = 70.9 kg +/- 17.8; height = 174.0 cm +/- 8.1) with AKPS currently using patella taping procedures with a decrease in their symptoms participated. Each subject had Merchant's view x-rays taken pre- and post-taping while performing an isometric quadriceps contraction to determine patella rotation and patella congruency angles. Subjects also completed a visual analog pain scale after performing a 0.2 m (8") step-down both pre- and post-taping. Paired t-tests revealed no significant change in patellofemoral congruency (P = 0.98) and patella rotation angles (P = 0.80). Significant reduction (50%) in subject pain level was revealed by the visual analog scale (t(15) = 4.99; P < 0.0005). Results demonstrate that patella taping significantly reduced the perceived pain levels during a 0.2-m step-down; however, this reduction in pain was not associated with patella position changes.