Lower Extremity Strength and Mechanics During Jumping in Women With Patellofemoral Pain

Context: Lower extremity (LE) weakness might be associated with altered mechanics during weight bearing in subjects with patellofemoral pain syndrome (PFPS). Objective: To analyze LE strength, mechanics, and the association between these variables among women with and without PFPS during a simulated athletic task. Design: Case control. Setting: Motion-analysis laboratory. Subjects: 20 women with PFPS and 20 healthy women. Main Outcome Measures: Peak isometric lateral trunk-flexion, hipabduction, hip external-rotation, knee-flexion, and knee-extension strength, as well as hip- and knee-joint excursions and angular impulses during single-leg jumps. Results: PFPS subjects produced less hip-abduction, hip external-rotation, and trunk lateral- flexion force than the control group. The PFPS group also demonstrated greater hipadduction excursion and hip-abduction impulses. The association between the strength measurements and LE mechanics was low. Conclusions: Women with PFPS demonstrate specific weaknesses and altered LE mechanics. Weakness is not, however, highly correlated with observed differences in mechanics. ABSTRACT FROM AUTHO

Effects of Medially Wedged Foot Orthoses on Knee and Hip Joint Running Mechanics in Females With and Without Patellofemoral Pain Syndrome.

We examined the effects of medially wedged foot orthoses on knee and hip joint mechanics during running in females with and without patellofemoral pain syndrome (PFPS). We also tested if these effects depend on standing calcaneal eversion angle. Twenty female runners with and without PFPS participated. Knee and hip joint transverse and frontal plane peak angle, excursion, and peak internal knee and hip abduction moment were calculated while running with and without a 6° full-length medially wedged foot orthoses. Separate 3-factor mixed ANOVAs (group [PFPS, control] x condition [medial wedge, no medial wedge] x standing calcaneal angle [everted, neutral, inverted]) were used to test the effect of medially wedged orthoses on each dependent variable. Knee abduction moment increased 3% (P = .03) and hip adduction excursion decreased 0.6° (P < .01) using medially wedged foot orthoses. No significant group x condition or calcaneal angle x condition effects were observed. The addition of medially wedged foot orthoses to standardized running shoes had minimal effect on knee and hip joint mechanics during running thought to be associated with the etiology or exacerbation of PFPS symptoms. These effects did not appear to depend on injury status or standing calcaneal posture. ABSTRACT FROM AUTHO

Prey morphology constrains the feeding ecology of an aquatic generalist predator

Abstract. Resource availability and accessibility are primary factors guiding the distribution and abundance of organisms. For generalists, prey availability reflects both prey abundance and differences in quality among prey taxa. Although some aspects of prey quality, such as nutritional composition, are well studied, our understanding of how prey morphology contributes to overall prey quality is limited. Because snakes cannot reduce prey size by mastication, many aspects of their feeding ecology (e.g., maximum prey size, feeding performance, and the degree of postprandial locomotor impairment) may be affected by prey shape. We conducted a uniquely comprehensive comparison of prey quality for a generalist species, the banded watersnake (Nerodia fasciata), using prey that were similar in mass and presumably similar in nutritional composition but different in shape and habitat association. Specifically, we compared nutritional composition and shape of paedomorphic salamanders (Ambystoma talpoideum) and sunfish (Lepomis marginatus) and used a series of repeatedmeasures experiments to examine feeding performance (number of prey consumed, maximum prey size, and intra-oral transport time), digestive metabolism (specific dynamic action, SDA), and postprandial locomotor performance of snakes fed Ambystoma and Lepomis. Cost of digestion was similar between the prey types, likely reflecting their similar nutritional composition. However, snakes consumed larger Ambystoma than Lepomis and intra-oral transport time was much shorter for Ambystoma. Snakes fed Lepomis also suffered greater reduction in crawling speed than those fed Ambystoma. These differences highlight the need for behaviorally integrated approaches to understanding prey quality and support field observations of the importance of amphibian prey for juvenile watersnakes

Landscape-Scale Effects of Supra-Seasonal Drought on Semi-Aquatic Snake Assemblages

Climate change is predicted to alter the frequency and intensity of precipitation events, placing stress on freshwater aquatic ecosystems and their associated wildlife. Thus, understanding interspecific variation in drought sensitivity and the repeatability of those responses across heterogeneous landscapes is critical. Semi-aquatic snakes serve important roles within aquatic ecosystems and several species are threatened. Yet, little is known about the effects of drought on semi-aquatic snake populations or assemblages. We systematically trapped 20 isolated wetlands in South Carolina before (2006) and after (2013) a multi-year supra-seasonal drought to determine drought-induced shifts in occupancy and detection for five semi-aquatic snake species. Our results confirm that supra-seasonal drought differentially affects semi-aquatic snake species across landscape scales. Specifically, site occupancy decreased dramatically following drought for banded watersnakes (Nerodia fasciata) (0.95 to 0.69) and Florida green watersnakes (Nerodia floridana) (0.32 to 0.05), but was relatively unchanged for black swamp snakes (Seminatrix pygaea), mudsnakes (Farancia abacura) and glossy crayfish snakes (Regina rigida). Species lacking adaptations that make them resistant or resilient to drought may become locally extirpated if climate change projections are realized or landscapes are degraded or fragmented in ways that prevent drought recovery

Foraging habitat selection of shrubland bird community in tropical dry forest

Habitat loss due to increasing anthropogenic disturbance is the major driver for bird population declines across the globe. Within the Eastern Ghats of India, shrubland bird communities are threatened by shrinking of suitable habitats due to increased anthropogenic disturbance and climate change. The development of an effective habitat management strategy is hampered by the absence of data for this bird community. To address this knowledge gap, we examined foraging sites for 14 shrubland bird species, including three declining species, in three study areas representing the shrubland type of forest community in the Eastern Ghats. We recorded microhabitat features within an 11 m radius of observed foraging points and compared these data with similar data from random plots. We used chi-square to test the association between plant species and bird species for sites where they were observed foraging. We observed significant differences between foraging sites of all the study species and random plots, thus indicating selection for foraging habitat. Using linear discriminant analysis, we found that the microhabitat features important for the bird species were shrub density, vegetational height, vertical foliage stratification, grass height, and percent rock cover. Our results show that diet guild and foraging strata influence the foraging microhabitat selection of a species (e.g., ground-foraging species differed significantly from other species). Except for two species, all focal birds were associated with at least one plant species. The plant-bird association was based on foraging, structural, or behavioral preferences. Several key factors affecting foraging habitat such as shrub density can be actively managed at the local scale. Strategic and selective harvesting of forest products and a spatially and temporally controlled livestock grazing regime may allow regeneration of scrubland and create conditions favorable to birds

Can invasive Burmese pythons inhabit temperate regions of the southeastern United States?

Abstract Understanding potential for range expansion is critical when evaluating the risk posed by invasive species. Burmese pythons (Python molurus bivittatus) are established in southern Florida and pose a significant threat to native ecosystems. Recent studies indicate that climate suitable for the species P. molurus exists throughout much of the southern United States. We examined survivorship, thermal biology, and behavior of Burmese pythons from South Florida in a semi-natural enclosure in South Carolina, where winters are appreciably cooler than in Florida, but within the predicted region of suitable climate. All pythons acclimated to the enclosure, but most died after failing to seek appropriate refugia during sub-freezing weather. The remaining snakes used refugia but died during an unusually cold period in January 2010. Although all snakes died during the study, most survived extended periods at temperatures below those typical of southern Florida and none exhibited obvious signs of disease. Our study represents a first step in evaluating the results of climate matching models and we address factors that may affect range expansion in this invasive species

Remote Ischaemic Conditioning Combined With Bimanual Task Training to Enhance Bimanual Skill Learning and Corticospinal Excitability in Children With Unilateral Cerebral Palsy: A Study Protocol of a Single Centre, Phase Ii Randomised Controlled Trial

INTRODUCTION: Children with unilateral cerebral palsy (UCP) have difficulty in bimanual coordination that restricts the child\u27s independence in daily activities. Although several efficacious interventions to improve bimanual coordination exist, these interventions often require higher training doses and have modest effect sizes. Thus, there is a critical need to find an effective priming agent that, when paired with task-specific training, will facilitate neurobiological processes to enhance the magnitude of training effects and subsequently improve functional capabilities of children with UCP. The aim of this study is to determine the effects of a novel priming agent, remote ischaemic conditioning (RIC), combined with bimanual training on bimanual skill learning and corticospinal excitability in children with UCP. METHODS AND ANALYSES: 46 children, aged 8-16 years, will be randomly assigned to receive RIC or sham conditioning combined with 5 days of bimanual skill (cup stacking) training (15 trials per session). RIC or sham conditioning will be performed with a standard conditioning protocol of five cycles of alternative inflation and deflation of a pressure cuff on the affected arm with the pressure of at least 20 mm Hg above systolic blood pressure for RIC and 25 mm Hg for sham conditioning. Primary outcomes will be movement time and corticospinal excitability measures determined with a single-pulse transcranial magnetic stimulation (TMS). Secondary outcomes include Assisting Hand Assessment, spatio-temporal kinematic variables and paired pulse TMS measures. All measures will be conducted before and immediately after the intervention. A mixed model analysis of variance will test the group×time interaction for all outcomes with group (RIC and sham) as between-subject and time (preintervention, postintervention) as within-subject factors. ETHICS AND DISSEMINATION: The study has been approved by the University Medical Centre Institutional Review Board (UMCIRB #21-001913). We will disseminate the study findings via peer-reviewed publications and presentations at professional conferences. TRIAL REGISTRATION NUMBER: NCT05777070