Growth Functions of Fr-sets

2010 Mathematics Subject Classification: 05C30, 20E08, 20F65.In this paper we consider an open problem from [1], regarding the description of the growth functions of the free group acts. Using the language of graphs, we solve this problem by providing the necessary and sufficient conditions for a function to be a growth function for a free group act

MUSCLE ACTIVATION PATTERNS DURING AN ICE HOCKEY SLAP SHOT

The ability to shoot the puck with maximum velocity and accuracy is one of the key components to optimal hockey performance. Of the many types of shots in hockey, the most powerful is the slap shot. A successful slap shot requires a combination of strength, speed, precise timing, and the proper stick choice (Pearsall et aI., 2000; Fergenbaum et aI., 2004). The slap shot consists of four key events -start, top of swing, impact and end. The muscle activation patterns during each of these phases are essential in designing training programs to improve shot velocity (Pan et aI., 1998) and may vary as a function of skill level (Woo, 2004). As such, the purpose of this study was to use three-dimensional kinematics and electromyography (EMG) to conduct a preliminary analysis of the muscle activation patterns during each phase of the slap shot in male, recreational and elite hockey players

Optimal ridge penalty for real-world high-dimensional data can be zero or negative due to the implicit ridge regularization

A conventional wisdom in statistical learning is that large models require strong regularization to prevent overfitting. Here we show that this rule can be violated by linear regression in the underdetermined $n\ll p$ situation under realistic conditions. Using simulations and real-life high-dimensional data sets, we demonstrate that an explicit positive ridge penalty can fail to provide any improvement over the minimum-norm least squares estimator. Moreover, the optimal value of ridge penalty in this situation can be negative. This happens when the high-variance directions in the predictor space can predict the response variable, which is often the case in the real-world high-dimensional data. In this regime, low-variance directions provide an implicit ridge regularization and can make any further positive ridge penalty detrimental. We prove that augmenting any linear model with random covariates and using minimum-norm estimator is asymptotically equivalent to adding the ridge penalty. We use a spiked covariance model as an analytically tractable example and prove that the optimal ridge penalty in this case is negative when $n\ll p$

An Update on the 2004 Pre-Feasibility Study for a Fixed Link between Labrador and the Island of Newfoundland

This study was intended as a follow‐up to a study originally undertaken by the Harris Centre back in 2004. The purpose of this current new study is, first, to determine to what extent new geological research, innovations intunneling technology, changes in labour costs, inflation or other factors may have an impact (positive or negative) on the original cost and time estimates. Secondly, the study aims to measure some possible impacts on the economy of the province overall and on those regions of the province that would be most affected by a change in traffic patterns

Report of an educational psychology internship at Harlow College, Harlow, England including a research report on how Harlow College can better meet the needs of women returners

To fulfill the requirements for the degree of Master of Education in School Counselling, this report provides an overview of the Author's internship experiences and research at Harlow College in Harlow, Essex, England. The report is divided into two sections: The Internship and the Research Component. The first section provides a rationale for an Internship in England, a description of the internship setting including: a brief history of Harlow Town; a description of Harlow College facilities; a discussion of experiences; and recommendations for future graduate students. The second section is a summary of the Author's research at Harlow College. This research examined how Harlow College can better meet the needs women returners or re-entry women, as commonly referred in the English literature. The results of this qualitative research suggest Harlow College is meeting many of the needs of women returners, however, there are still areas where improvements could be made. Some of the suggested recommendations include: affordable creche facility on campus; better lighting in the parking lot and on campus; a mandatory session with a careers guidance person for all women returners (full and part-time); an orientation session for all mature returners; scholarships for women returners; alternate teaching and evaluation methods; flexibility and accommodations to students who may have to miss time due to family commitments; support groups for mature students; and counselling services

Drawing lines at the sand: evidence for functional vs. visual reef boundaries in temperate Marine Protected Areas.

Marine Protected Areas (MPAs) can either protect all seabed habitats within them or discrete features. If discrete features within the MPA are to be protected humans have to know where the boundaries are. In Lyme Bay, SW England a MPA excluded towed demersal fishing gear from 206 km(2) to protect rocky reef habitats and the associated species. The site comprised a mosaic of sedimentary and reef habitats and so 'non reef' habitat also benefited from the MPA. Following 3 years protection, video data showed that sessile Reef Associated Species (RAS) had colonised sedimentary habitat indicating that 'reef' was present. This suggested that the functional extent of the reef was potentially greater than its visual boundary. Feature based MPA management may not adequately protect targeted features, whereas site based management allows for shifting baselines and will be more effective at delivering ecosystem goods and services

Acute effects of walking with Nordic poles in persons with mild to moderate low-back pain

International Journal of Exercise Science 9(4): 507-513, 2016. Regular walking with or without Nordic poles is effective over time at reducing discomfort in individuals with chronic low back pain (LBP). Nordic pole use increases balance and stability, distributes weight through the arms and torso, and decreases loading of the spine and lower limbs. The purpose of this study was to determine if Nordic poles would reduce perceived acute discomfort while self-paced walking in individuals with LBP. We also examined whether walking with or without poles increased heart rate (HR) and ratings of perceived exertion (RPE) or speed of movement. Subjects included 20 adults (12 males, 8 females; mean age of 45.1±16.3) who were experiencing LBP of at least six months’ duration (Oswestry Disability Index (ODI): mean 17 ± 8%, range 6-36% indicating minimal to moderate disability) with no current active flare-up. Participants walked a predetermined dirt-path course (805 m or 0.5 mi) with and without poles in randomized order. Data were analyzed using a 2 X 2 repeated measures ANOVA (Condition X Time), where Condition was poles vs no poles and Time was pre- and post-walk. HR and RPE increased significantly from walking the course, whereas pain did not change. There were also no differences between walking with or without poles for pain (ODI Sec #1: 0.2 points, p=0.324), HR (4 bpm, p=0.522) and RPE (0 points, p=0.759). The mean course time (sec) was slower with poles: 617±87 vs 566±65 (p\u3c0.001). Unexpectedly, there was a noticeable drop in pain following the warm up which was done using poles (0.9 points, p\u3c0.001). Nordic pole use is well tolerated in those with current back pain and can be encouraged, however it cannot be recommended as a superior method of addressing acute symptoms when walking

Balamory revisited: An evaluation of the screen tourism destination-tourist nexus

Post-print version previously archived in Stirling University archive. Final version published by Elsevier; available online at http://www.journals.elsevier.com

C mobilisation in disturbed tropical peat swamps: old DOC can fuel the fluvial efflux of old carbon dioxide, but site recovery can occur

Southeast-Asian peat swamp forests have been significantly logged and converted to plantation. Recently, to mitigate land degradation and C losses, some areas have been left to regenerate. Understanding how such complex land use change affects greenhouse gas emissions is essential for modelling climate feedbacks and supporting land management decisions. We carried out field research in a Malaysian swamp forest and an oil palm plantation to understand how clear-felling, drainage, and illegal and authorized conversion to oil palm impacted the C cycle, and how the C cycle may change if such logging and conversion stopped. We found that both the swamp forest and the plantation emit centuries-old CO2 from their drainage systems in the managed areas, releasing sequestered C to the atmosphere. Oil palm plantations are an iconic symbol of tropical peatland degradation, but CO2 efflux from the recently-burnt, cleared swamp forest was as old as from the oil palm plantation. However, in the swamp forest site, where logging had ceased approximately 30 years ago, the age of the CO2 efflux was modern, indicating recovery of the system can occur. 14C dating of the C pool acted as a tracer of recovery as well as degradation and offers a new tool to assess efficacy of restoration management. Methane was present in many sites, and in higher concentrations in slow-flowing anoxic systems as degassing mechanisms are not strong. Methane loading in freshwaters is rarely considered, but this may be an important C pool in restored drainage channels and should be considered in C budgets and losses