Understory restoration in Hamilton urban forests

Research was undertaken to determine how the understory vegetation of Hamilton urban forests compares with reference old-growth forests in rural locations, identify causes for differences, and develop methods to enhance species diversity. Understory vegetation was measured in five rural old-growth forests and compared with 20 urban forests, categorised into four age groups, to assess differences in richness, composition and density. Environmental profiling quantified soil type, nutrient levels, pH, moisture content, understory light transmittance, temperature and vapour pressure deficit of selected forests to identify variation across the forest categories and determine if environmental conditions were the chief cause for vegetative differences. Three native species (Melicytus micranthus, Hedycarya arborea and Coprosma arborea), absent from or less abundant in urban forests, were reintroduced into forest sites to assess their growth, survival and potential for becoming a prominent component in Hamilton City forests. Urban forests displayed reduced native understory diversity comprising only 61.5% of the native understory species found in the rural old-growth forests. Native understory species richness and density decreased from the rural old-growth forest category to the youngest urban forest group. Rural old-growth forests averaged 7.96 species and 41.28 stems per 50 m² compared to 2.68 species and 8.20 stems per 50 m² in the youngest urban forests. The exotic understory stem density trend was reverse. Reduced understory diversity in second-growth and urban forests is widely reported overseas but has not been quantified in New Zealand previously. Soil nutrients and acidity increased from the youngest to the oldest urban forest category. Light transmittance into the understory decreased with forest age from 18.43% in the youngest urban forest group to 4.17% in the rural old-growth forest category during winter and spring. Buffering patterns were evident in rural oldgrowth forests with higher temperatures and vapour pressure deficits outside the forests by as much as 3 ºC and 0.3 kPa respectively during the day, compared to the forest interior. Similar patterns were evident in urban forests during spring but the interior temperatures and vapour pressure deficits were not as low, compared to the rural forests. Environmental profiling proved there were significant differences in environmental conditions between the forest categories and that these were within the range of values reported elsewhere in New Zealand. Survival and growth rates between 77.8 to 100% and 2.7 to 12.1 cm respectively, for the three translocated species over the measured seven months were on par with other New Zealand trials and suggest the selected species can grow and establish viable populations within urban forests. The reintroduction success further indicates that the reduced diversity of urban forests is likely to result from the effects of fragmentation and isolation and urban pressures. Active reintroduction of missing or less abundant native understory species is the best method to improve diversity in Hamilton urban forests. The species experimented with should be included in forest enrichment planting plans as early as 5 to 15 years. Management plans should address active removal of exotic species including methods for manipulation of developing vegetation to favour enhancement of native understory diversity in urban forests

Can a single-legged squat provide insight into movement control and loading during dynamic sporting actions in athletic groin pain patients?

Context: Chronic athletic groin pain (AGP) is common in field sports and has been associated with abnormal movement control and loading of the hip and pelvis during play. A single-legged squat (SLS) is commonly used by clinicians to assess movement control but whether it can provide insight into control during more dynamic sporting movements in AGP patients is unclear. Objective: To determine the relationships between biomechanical measures in a SLS and these same measures in a single-legged drop landing, single-legged hurdle hop and a cutting manoeuvre in AGP patients. Design: Cross-sectional study. Setting: Biomechanics laboratory. Patients: Forty recreational field sports players diagnosed with AGP. Intervention: A biomechanical analysis of each individual’s SLS, drop-landing, hurdle hop and cut was undertaken. Main Outcome Measures: Hip, knee and pelvis angular displacement, and hip and knee peak moments. Pearson product moment correlations were used to examine relationships between SLS measures and equivalent measures in the other movements. Results: There were no significant correlations between any hip or pelvis measure in the SLS with these same measures in the drop landing, hurdle hop or cut (r range = 0.03 - 0.43, P > 0.05). Knee frontal and transverse plane angular displacement were related in the SLS and drop landing only, while knee moments were related in the SLS, drop-landing and hurdle hop (r range = 0.50 - 0.67, P < 0.05). Conclusion: For AGP patients, a SLS did not provide a meaningful insight into hip and pelvis control or loading during sporting movements that are associated with injury development. The usefulness of a SLS test in the assessment of movement control and loading in AGP patients is thus limited. The SLS provided a moderate insight into knee control while landing and therefore may be of use in the examination of knee injury risk

THE EFFECTS OF AN EXERCISE INTERVENTION ON THE BIOMECHANICS OF AN ATHLETIC GROIN PAIN COHORT DURING THE LATERAL HURDLE HOP

The purpose of this study was to determine the kinematic and kinetic variables that may be of importance in the investigation of athletic groin pain (AGP). This was achieved by examining the 3D kinematics and kinetics of 70 AGP patients, recorded during a lateral hurdle hop, pre and post a successful exercise rehabilitation program. Results from the Copenhagen Hip and Groin Outcome Score questionnaire demonstrated significant improvements in 5 out of the 6 subscales. Analysis of characterising phases was used to examine kinematic and kinetic changes. Multiple significant changes were identified in both angles at the pelvis, hip and thorax and moments at the hip. Findings of this study provide an insight into the kinematic and kinetic variables of importance in AGP

CHANGES IN HIP FORCE VECTOR AFTER ATHLETIC GROIN PAIN REHABILITATION DURING A RUNNING CUT

The purpose of this study was to examine changes in hip force vectors after successful athletic groin pain rehabilitation. Forty athletes with athletic groin pain that underwent a rehabilitation intervention participated in this study. Hip force magnitude, direction and their combination were examined using a continuous waveform analysis. Hip posterior and medial force at the start and end of the movement decreased following rehabilitation, while superior forces increased (over most of the movement cycle). Findings suggest that athletes with groin pain benefit from a rehabilitation intervention that decreases posterior and medial hip joint forces

Fat quantification in MRI-defined lumbar muscles

Some studies suggest fat infiltration in the lumbar muscles (LM) is associated with lower back pain (LBP) in adults. Usually fat in MRI-defined lumbar muscles is qualitatively valuated by visual grading via a 3 point scale, whereas a quantitative continuous (0 - 100%) approach may provide a greater insight. In this paper, we propose a method to precisely quantify the fat content / infiltration in a user-defined region of the lumbar muscles, which may aid better diagnosis. The key steps are segmenting the region of interest (ROI) from the lumbar muscles, identifying the fatty regions in the segmented region based on the selected threshold and softness levels, computing the parameters (such as total and region-wise fat content percentage, total-cross sectional area (TCSA), functional cross- sectional area (FCSA)) and exporting the computations and associated patient information from the MRI, into a atabase. A standalone application using MATLAB R2010a was developed to perform the required computations along with an intuitive GUI

The delay-reward heuristic: What do people expect in intertemporal choice tasks?

Recent research has shown that risk and reward are positively correlated in many environments, and that people have internalized this association as a "risk-reward heuristic": when making choices based on incomplete information, people infer probabilities from payoffs and vice-versa, and these inferences shape their decisions. We extend this work by examining people's expectations about another fundamental trade-off-that between monetary reward and delay. In 2 experiments (total N = 670), we adapted a paradigm previously used to demonstrate the risk-reward heuristic. We presented participants with intertemporal choice tasks in which either the delayed reward or the length of the delay was obscured. Participants inferred larger rewards for longer stated delays, and longer delays for larger stated rewards; these inferences also predicted people's willingness to take the delayed option. In exploratory analyses, we found that older participants inferred longer delays and smaller rewards than did younger ones. All of these results replicated in 2 large-scale pre-registered studies with participants from a different population (total N = 2138). Our results suggest that people expect intertemporal choice tasks to offer a trade-off between delay and reward, and differ in their expectations about this trade-off. This "delay-reward heuristic" offers a new perspective on existing models of intertemporal choice and provides new insights into unexplained and systematic individual differences in the willingness to delay gratification

CHANGES IN THE BIOMECHANICS OF A REACTIVE CUTTING MANOEUVRE IN AN ATHLETIC GROIN PAIN COHORT FOLLOWING A SUCCESSFUL REHABILITATION INTERVENTION

Athletic groin pain (AGP) is prevalent in field sports that require rapid changes of direction. The purpose of this study was to investigate the kinetic and kinematic changes that occurred in an unplanned reactive cutting manoeuvre following a successful rehabilitation intervention. Kinematics and kinetics were analysed using statistical parametric mapping in 23 patients before and after an exercise intervention programme. Significant improvements were found in all subscales of the Copenhagen Hip and Groin Outcome Score and biomechanical changes were identified at the pelvis, knee and ankle. These findings provide insight into mechanical variables of potential importance in AGP as identified during a manoeuvre based on a common sporting task