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Context: Athletes who have undergone an anterior cruciate ligament reconstruction often demonstrate more pronounced interlimb knee kinetic symmetry in comparison with uninjured athletes, even after they have completed rehabilitation. Part of the reason for the persistent asymmetry may be that sports medicine professionals are typically not able to assess knee joint kinetics within the clinic setting. Developing measures to assess knee joint kinetic symmetry could help to augment current rehabilitation practices. Objective: The purpose of this study was to explore the extent to which interlimb vertical ground reaction force (GRF) symmetry can predict knee kinetic symmetry during a drop landing task. Design: Cross-sectional study. Setting: Motion analysis laboratory. Participants: A total of 21 uninjured subjects (9 males and 12 females). Protocol: Three-dimensional kinematic data were collected using a multicamera system while subjects performed double-leg drop landings. GRF data were collected synchronously using 2 adjacent force plates. Main Outcome Measures: Knee joint moments and power were calculated for both limbs during the landing trials. An interlimb symmetry index (dominant/nondominant limb) was calculated for both the peak knee joint moment and power variables, as well as for the peak vertical GRFs. Linear regression analyses were performed to determine if the degree of symmetry in the peak vertical GRFs predicted the degree of symmetry for the kinetic variables. Results: The symmetry index for the vertical GRFs was a significant predictor of the symmetry indices for the knee joint moments (r =.81; P <.001) and power (r =.88; P <.001). Conclusion: Interlimb symmetry in the peak vertical GRFs can be used to predict knee joint kinetic symmetry during a double-leg drop landing task. [ABSTRACT FROM AUTHOR]

Predicting species' range shifts under future climate is a central goal of conservation ecology. Studying populations within and beyond multiple species' current ranges can help identify whether demographic responses to climate change exhibit directionality, indicative of range shifts, and whether responses are uniform across a suite of species.We quantified the demographic responses of six native perennial prairie species planted within and, for two species, beyond their northern range limits to a 3‐year experimental manipulation of temperature and precipitation at three sites spanning a latitudinal climate gradient in the Pacific Northwest, USA. We estimated population growth rates (λ) using integral projection models and tested for opposing responses to climate in different demographic vital rates (demographic compensation).Where species successfully established reproductive populations, warming negatively affected λ at sites within species' current ranges. Contrarily, warming and drought positively affected λ for the two species planted beyond their northern range limits. Most species failed to establish a reproductive population at one or more sites within their current ranges, due to extremely low germination and seedling survival. We found little evidence of demographic compensation buffering populations to the climate treatments.Synthesis. These results support predictions across a suite of species that ranges will need to shift with climate change as populations within current ranges become increasingly vulnerable to decline. Species capable of dispersing beyond their leading edges may be more likely to persist, as our evidence suggests that projected changes in climate may benefit such populations. If species are unable to disperse to new habitat on their own, assisted migration may need to be considered to prevent the widespread loss of vulnerable species. [ABSTRACT FROM AUTHOR]

Background and Purpose: The aim of this study was to evaluate an automatic multi-atlas-based segmentation method for generating prostate, peripheral (PZ), and transition zone (TZ) contours on MRIs with and without fat saturation (±FS), and compare MRIs from different vendor MRI systems.Methods: T2-weighted (T2) and fat-saturated (T2FS) MRIs were acquired on 3T GE (GE, Waukesha, WI, USA) and Siemens (Erlangen, Germany) systems. Manual prostate and PZ contours were used to create atlas libraries. As a test MRI is entered, the procedure for atlas segmentation automatically identifies the atlas subjects that best match the test subject, followed by a normalized intensity-based free-form deformable registration. The contours are transformed to the test subject, and Dice similarity coefficients (DSC) and Hausdorff distances between atlas-generated and manual contours were used to assess performance.Results: Three atlases were generated based on GE_T2 (n = 30), GE_T2FS (n = 30), and Siem_T2FS (n = 31). When test images matched the contrast and vendor of the atlas, DSCs of 0.81 and 0.83 for T2 ± FS were obtained (baseline performance). Atlases performed with higher accuracy when segmenting (i) T2FS vs. T2 images, likely due to a superior contrast between prostate vs. surrounding tissue; (ii) prostate vs. zonal anatomy; (iii) in the mid-gland vs. base and apex. Atlases performance declined when tested with images with differing contrast and MRI vendor. Conversely, combined atlases showed similar performance to baseline.Conclusion: The MRI atlas-based segmentation method achieved good results for prostate, PZ, and TZ compared to expert contoured volumes. Combined atlases performed similarly to matching atlas and scan type. The technique is fast, fully automatic, and implemented on commercially available clinical platform. [ABSTRACT FROM AUTHOR]

Background: Intravenous dihydroergotamine (DHE) has well‐established efficacy for the acute treatment of migraine, but its use is limited by the need for in‐hospital administration and the nausea/vomiting associated with a high maximum plasma concentration (Cmax). Inhalation is an alternative to intravenous dosing. The surface area of the lung allows for rapid absorption of a self‐administered dose. Objective: This study evaluated the safety, tolerability, and systemic pharmacokinetics (PK) of a dry powder formulation (PUR3100) DHE when delivered via inhalation compared to intravenous delivery. Method s : In this double‐blind, double‐dummy Phase 1 study, healthy volunteers (N = 26) were randomized (1:1:1:1) to one of four groups: orally inhaled placebo plus intravenous DHE 1.0 mg or orally inhaled PUR3100 (0.5, 1.0, or 1.5 mg) plus intravenous placebo. Blood samples were drawn pre‐dose and at time points post‐dose over 48 h. Standard PK and safety parameters were assessed and values for Cmax and area under plasma concentration time curve (AUC) were used to assess comparative exposures of PUR3100 versus intravenous DHE. Results: All doses of PUR3100 were associated with a lower incidence of nausea (21% vs. 86%), vomiting (0% vs. 29%), and headache (16% vs. 57%) compared to intravenous DHE. The PK profile of PUR3100 versus intravenous DHE was characterized by a similar mean time to Cmax (5 vs. 5.5 min), with reduced AUC0–2h (1120–4320 vs. 6340), and a lower Cmax (3620–14,400 vs. 45,000). Compared to intravenous DHE 1.0 mg, the highest nominal PUR3100 dose (1.5 mg), which delivers a fine‐particle dose of approximately 0.9 mg to the lungs, had a geometric mean ratio percentage (90% confidence interval [CI]) for Cmax of 32% [17.2, 59.6] and AUC0–inf of 93% (62.9, 138.5), the latter of which was not significantly different. Conclusions: Inhaled PUR3100 is associated with rapid systemic PK within the therapeutic window and an improved safety profile relative to intravenous DHE. Plain Language Summary: Intravenous dihydroergotamine (DHE) works for the acute treatment of migraine; however, it must be given in a hospital or clinic and has side‐effects including nausea and vomiting. A dry powder formulation of DHE (PUR3100) delivered by oral inhalation had fewer side‐effects than intravenous DHE in healthy volunteers. The pharmacokinetics (the amount of the study drug in blood) showed that inhaled PUR3100 was associated with rapid absorption of DHE into the blood within the desired range associated with pain relief. [ABSTRACT FROM AUTHOR]