Mirroring clinical guidelines, recent Performance Validity Test (PVT) research emphasizes using ≥ 2 criterion PVTs to optimally identify validity groups when validating/cross-validating PVTs; ...however, even with multiple measures, the effect of
which
specific PVTs are used as criterion measures remains incompletely explored. This study investigated the accuracy of varying two-PVT combinations for establishing validity status and how adding a third PVT or applying more liberal failure cut-scores affects overall false-positive (FP)/-negative (FN) rates. Clinically referred veterans (
N
= 114; 30% clinically identified as invalid) completing a six-PVT protocol as during their evaluation were included. Concordance rates were calculated across all possible two-and three-PVT combinations at conservative and liberal cutoffs. Two-PVT combinations classified 72–91% of valid (0–4% FPs) and 17–74% of invalid (0–40% FNs) cases, and three-PVT combinations classified 67–86% of valid (0–6% FPs) and 57–97% of invalid (0–24% FNs) at conservative cutoffs. Liberal cutoffs classified 53–86% of valid (0–15% FPs) and 39–82% of invalid (0–30% FNs) cases for two-PVT combinations and 46–75% of valid (3–27% FPs) and 60–97% of invalid (0–17% FNs) cases for three-PVT combinations. Irrespective of whether a two-or three-PVT combination or conservative/liberal cutoffs were used, many valid and invalid cases failed only one PVT (3–68%).Two-PVT combinations produced high FNs and were less accurate than three-PVTs for detecting invalid cases, though variable accuracy was found within both types of combinations based on the specific PVTs in the combination. Thus, both PVT quantity
and
quality are important for accurate validity classification in research studies to ensure reliability and replicability of findings. Applying more liberal cutoffs yielded increased sensitivity, but with generally higher FPs yielding problematic specificity, particularly for three-PVT combinations.
•Calculated CFD fields to resolve the wind near overhead transmission lines.•A year of forecasted data from the HRRR model analyzed compared to weather stations.•HRRR model data used to in the CFD ...model to find local wind speeds over time.•Forecasted dynamic line rating shown to be advantageous to static ratings.
This study looks at forecasted dynamic line ratings in southern Idaho by using data from the high resolution rapid-refresh (HRRR) model for forecasted weather conditions. The HRRR model can provide accurate 18-h forecasts with a 15-min temporal resolution. Typical static ratings used for overhead transmission lines use overly conservative assumptions for local weather conditions, such as using the maximum solar irradiance and ambient temperature measured during the summer, combined with low wind speed for an entire season. The HRRR forecast model used here has high spatial resolution to provide local forecast conditions along the entire length of a transmission line. The area that is of interest in this study is in southern Idaho, spanning a total of 15,000 square kilometers. The forecasted weather data are coupled with a computational fluid dynamics (CFD) model of the wind in the region for fine-scale resolution of convective cooling rates on the midpoint of each individual transmission-line span. This high-fidelity approach can be used to find the minimum ampacity across all given midpoints of a transmission line to determine the limit to be used for the line rating. The ability to increase the overhead line rating above the conservative static approach with the forecasted weather data provides a large potential to alleviate congestion and provide data for utility-market transactions, as well as benefits for wind energy generation through concurrent cooling. This study shows that for the region of interest, using forecasted weather data coupled with CFD modeling can calculate DLR ampacity rating above static over 90% of the time, with a small relative error in the forecasted ampacity over time.
The use of transgenic crops as feeds for ruminant animals has prompted study of the possible uptake of transgene fragments by ruminal micro-organisms and/or intestinal absorption of fragments ...surviving passage through the rumen. The persistence in buffered ruminal contents of seven different recombinant DNA fragments from GM rapeseed expressing the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) transgene was tracked using PCR. Parental and transgenic (i.e. glyphosphate-tolerant; Roundup Ready, Monsanto Company, St Louis, MO, USA) rapeseed were incubated for 0, 2, 4, 8, 12, 24 and 48 h as whole seeds, cracked seeds, rapeseed meal, and as pelleted, barley-based diets containing 65 g rapeseed meal/kg. The seven transgene fragments ranged from 179 to 527 bp and spanned the entire 1363 bp EPSPS transgene. A 180 bp ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) small subunit fragment and a 466 bp 16S rDNA fragment were used as controls for endogenous rapeseed DNA and bacterial DNA respectively. The limit of detection of the PCR assay, established using negative controls spiked with known quantities of DNA, was 12.5 pg. Production of gas and NH3 was monitored throughout the incubation and confirmed active in vitro fermentation. Bacterial DNA was detected in all sample types at all time points. Persistence patterns of endogenous (Rubisco) and recombinant (EPSPS) rapeseed DNA were inversely related to substrate digestibility (amplifiable for 48, 8 and 4 h in whole or cracked seeds, meal and diets respectively), but did not differ between parental and GM rapeseed, nor among fragments. Detection of fragments was representative of persistence of the whole transgene. No EPSPS fragments were amplifiable in microbial DNA, suggesting that transformation had not occurred during the 48 h incubation. Uptake of transgenic DNA fragments by ruminal bacteria is probably precluded or time-limited by rapid degradation of plant DNA upon plant cell lysis.
The location (proximal vs. distal) of elbow medial ulnar collateral ligament (MUCL) tears impacts clinical outcomes of non-operative treatment. The purposes of our study were to i) determine whether ...selective releases of the MUCL could be performed under ultrasound guidance without disrupting overlying soft tissues, ii) assess the difference in medial elbow stability for proximal and distal releases of the MUCL using stress ultrasound and a robotic testing device, and iii) elucidate the flexion angle that resulted in the greatest amount of medial elbow laxity after MUCL injury.
Sixteen paired, fresh-frozen elbow specimens were utilized. Valgus laxity was evaluated with both ultrasound (US) and robotic-assisted measurements before and after selective MUCL releases. A percutaneous ultrasound-guided technique was utilized to perform proximal MUCL releases in 8 elbows and distal MUCL releases in their matched pairs. The robot was used to determine the elbow flexion angle at which the maximum valgus displacement occurred for both proximally and distally released specimens. Open dissection was then performed to assess the accuracy of the percutaneous releases.
Percutaneous ultrasound-guided releases were successfully performed in 15 of 16 specimens. The proximal release resulted in greater valgus angle displacement (11° ± 2°) than the distal release (8° ± 2°) between flexion angles of 30° and 70° (p<0.0001 @30˚, p<0.0001 @40˚, p=0.001 @50˚, p=0.005 @60˚ and p=0.020 @70˚). Valgus displacement between release locations did not reach statistical significance between 80° and 120° (p=0.051 @80˚, p=0.131 @90˚, p=0.245 @100˚, p=0.400 @110˚ and p=0.532 @120˚). When comparing the values for mean increase in US delta gap (stressed - supported state) from pre- to post-MUCL release, the proximally released elbows had larger increases than the distally released elbows (5.0 mm proximal vs. 3.7 mm distal, p = 0.032). After MUCL release, maximum mean valgus displacement occurred at 49° of flexion.
Ultrasound-guided selective releases of the MUCL can be performed reliably without violating the overlying musculature. Valgus instability is not of greater magnitude for distal releases when compared to proximal. This suggests there must be alternative factors to explain the difference in clinical prognosis between distal and proximal tears. The observed flexion angle for maximum valgus laxity could have important implications for elbow positioning during ultrasound or fluoroscopic stress examination as well as surgical repair/reconstruction of the MUCL.
Manual wheelchair users exhibit pain related to repetitive and demanding shoulder activities of daily living. Wearable sensing systems like force measurement gloves can provide insights about upper ...extremity loading in the community and home environments. We calibrated and evaluated the accuracy of a novel force measurement glove with a body-worn data logger. The device was calibrated with loads of 0-800N applied to the palmar surface of the glove. Calibration conditions were tested that varied the stiffness of the material in the glove, the temperature, and the curvature of the force applicator. Calibration equations from each condition were evaluated by comparing the glove's force prediction with the output of an instrumented wheelchair rim during propulsion and weight relief exercises. The force measurement glove detected 72.7% of 355 propulsion peaks and had a strong linear correlation with the instrumented rim force measurements (r=0.80). The most accurate calibration equation was constructed using data from all conditions, with an RMS force measurement error of 64.7 N and 31.7 N for weight relief exercise and propulsion, respectively. The force measurement glove design described here may serve as a useful tool for detection of loading events and relative magnitude changes.
During decision making, neurons in multiple brain regions exhibit responses that are correlated with decisions. However, it remains uncertain whether or not various forms of decision-related activity ...are causally related to decision making. Here we address this question by recording and reversibly inactivating the lateral intraparietal (LIP) and middle temporal (MT) areas of rhesus macaques performing a motion direction discrimination task. Neurons in area LIP exhibited firing rate patterns that directly resembled the evidence accumulation process posited to govern decision making, with strong correlations between their response fluctuations and the animal's choices. Neurons in area MT, in contrast, exhibited weak correlations between their response fluctuations and choices, and had firing rate patterns consistent with their sensory role in motion encoding. The behavioural impact of pharmacological inactivation of each area was inversely related to their degree of decision-related activity: while inactivation of neurons in MT profoundly impaired psychophysical performance, inactivation in LIP had no measurable impact on decision-making performance, despite having silenced the very clusters that exhibited strong decision-related activity. Although LIP inactivation did not impair psychophysical behaviour, it did influence spatial selection and oculomotor metrics in a free-choice control task. The absence of an effect on perceptual decision making was stable over trials and sessions and was robust to changes in stimulus type and task geometry, arguing against several forms of compensation. Thus, decision-related signals in LIP do not appear to be critical for computing perceptual decisions, and may instead reflect secondary processes. Our findings highlight a dissociation between decision correlation and causation, showing that strong neuron-decision correlations do not necessarily offer direct access to the neural computations underlying decisions.
Wetland emissions remain one of the principal sources of uncertainty in the global atmospheric methane (CH4) budget, largely due to poorly constrained process controls on CH4 production in ...waterlogged soils. Process-based estimates of global wetland CH4 emissions and their associated uncertainties can provide crucial prior information for model-based top-down CH4 emission estimates. Here we construct a global wetland CH4 emission model ensemble for use in atmospheric chemical transport models (WetCHARTs version 1.0). Our 0.5° × 0.5° resolution model ensemble is based on satellite-derived surface water extent and precipitation reanalyses, nine heterotrophic respiration simulations (eight carbon cycle models and a data-constrained terrestrial carbon cycle analysis) and three temperature dependence parameterizations for the period 2009–2010; an extended ensemble subset based solely on precipitation and the data-constrained terrestrial carbon cycle analysis is derived for the period 2001–2015. We incorporate the mean of the full and extended model ensembles into GEOS-Chem and compare the model against surface measurements of atmospheric CH4; the model performance (site-level and zonal mean anomaly residuals) compares favourably against published wetland CH4 emissions scenarios. We find that uncertainties in carbon decomposition rates and the wetland extent together account for more than 80 % of the dominant uncertainty in the timing, magnitude and seasonal variability in wetland CH4 emissions, although uncertainty in the temperature CH4 : C dependence is a significant contributor to seasonal variations in mid-latitude wetland CH4 emissions. The combination of satellite, carbon cycle models and temperature dependence parameterizations provides a physically informed structural a priori uncertainty that is critical for top-down estimates of wetland CH4 fluxes. Specifically, our ensemble can provide enhanced information on the prior CH4 emission uncertainty and the error covariance structure, as well as a means for using posterior flux estimates and their uncertainties to quantitatively constrain the biogeochemical process controls of global wetland CH4 emissions.
Neurons in the macaque lateral intraparietal (LIP) area exhibit firing rates that appear to ramp upward or downward during decision-making. These ramps are commonly assumed to reflect the gradual ...accumulation of evidence toward a decision threshold. However, the ramping in trial-averaged responses could instead arise from instantaneous jumps at different times on different trials. We examined single-trial responses in LIP using statistical methods for fitting and comparing latent dynamical spike-train models. We compared models with latent spike rates governed by either continuous diffusion-to-bound dynamics or discrete "stepping" dynamics. Roughly three-quarters of the choice-selective neurons we recorded were better described by the stepping model. Moreover, the inferred steps carried more information about the animal's choice than spike counts.
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