Spelling suggestions: "subject:"power"" "subject:"lower""
161 |
Likelihood-Based Modulation Classification for Multiple-Antenna ReceiversRamezani-Kebrya, Ali 21 September 2012 (has links)
Prior to signal demodulation, blind recognition of the modulation
scheme of the received signal is an important task for intelligent
radios in various commercial and military applications such as
spectrum management, surveillance of broadcasting activities and adaptive
transmission. Antenna arrays provide spatial diversity and increase channel
capacity. This thesis focuses on the algorithms and performance analysis of
the blind modulation classification (MC) for a multiple antenna receiver configuration.
For a single-input-multiple-output (SIMO) configuration with unknown channel amplitude, phase, and noise variance, we
investigate likelihood-based algorithms for linear digital MC. The existing
algorithms are presented and extended to SIMO. Using recently proposed blind estimates of the unknown parameters, a
new algorithm is developed. In addition, two upper bounds on the classification performance of MC
algorithms are provided. We derive the exact Cramer-Rao Lower Bounds (CRLBs) of joint estimates of the unknown parameters for one- and two-dimensional amplitude modulations. The asymptotic behaviors of the CRLBs are obtained for the high signal-to-noise-ratio (SNR) region. Numerical results demonstrate the accuracy of the CRLB expressions and confirm that the expressions in the literature are special cases of our results. The classification performance of the proposed algorithm is compared with the existing algorithm and upper bounds. It is shown that the proposed algorithm outperforms the existing one significantly with reasonable computational complexity.
The proposed algorithm in this thesis can be used in modern intelligent radios equipped with multiple antenna receivers
and the provided performance analysis, i.e., the CRLB expressions, can be employed to design practical systems involving estimation of the unknown parameters
and is not limited to MC. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2012-09-21 00:51:43.938
|
162 |
The relationship between knee pain and body weight in early onset knee osteoarthritisTakacs, Judit 14 July 2011 (has links)
Osteoarthritis (OA) is a group of diseases entailing degradation of joints, and has been designated as one of the key conditions for special attention during the World Health Organization’s Bone and Joint Decade (2000-2010) (Brooks & Hart, 2000).
Research has demonstrated that body weight is the number one modifiable risk factor associated with the onset and progression of knee OA (Felson, 1996). However, exercise programs that aim to initiate weight loss and improve pain and function in knee OA often increase loading on the knee joint, contributing to degeneration of the knee and progression of the disease (Miyazaki et al, 2002). The introduction of a new anti-gravity treadmill, which utilizes a technology called Lower Body Positive Pressure (LBPP), allows the examination of the relationship between weight, knee pain and knee loading via knee acceleration during exercise. The null hypothesis states that there will be no significant difference in knee pain, knee function and knee joint acceleration when comparing full weight bearing and LBPP treadmill walking exercise in a young knee OA population.
Twenty-two overweight/obese patients with mild or moderate early-onset knee OA were recruited to complete two 25 minute treadmill walking sessions (one full weight-bearing and one LBPP walking session) one week apart and two walkway walking sessions. Knee pain and knee acceleration were recorded. Paired t-tests and ANOVAs were used to compare conditions. On average, an LBPP of 12.3% body weight reduction reduced knee pain in our population. Knee pain was significantly lower during LBPP walking than during full weight-bearing walking. Knee acceleration decreased with increasing LBPP. Heel strike and toe-off data from walkway walking trials illustrated significantly different knee acceleration about the knee (slow walking loads were lower / fast walking were higher), as compared to treadmill walking sessions. This study illustrates that treadmill walking at a minimal level of LBPP can decrease knee pain and attenuate knee joint loads while allowing patients to complete exercise programs aimed at initiating weight loss and improving pain and function in knee OA. LBPP appears to be a promising tool for rehabilitation for those with painful knee OA and other lower body musculoskeletal conditions.
|
163 |
Managing knee osteoarthritis: the effects of anti-gravity treadmill exercise on joint pain and physical functionChristian, Mathew 28 August 2012 (has links)
Knee osteoarthritis (OA) is a degenerative joint condition characterized by progressive joint pain, swelling, and loss of muscle and joint function for which there is no known cure. Current research indicates that the most important modifiable risk factor for the development and progression of knee OA is obesity, a condition that is increasingly common in older adults. Established treatment guidelines for knee OA recommend regular exercise for disease management. However, for obese patients weight-bearing exercise elicits large joint forces that can exacerbate symptoms and influence disease progression. Using a new anti-gravity treadmill capable of generating a lifting force called lower body positive pressure (LBPP), obese patients with knee OA can engage in regular physical activity while minimizing joint loading. The aim of this study was to assess the effect of a 12-week, anti-gravity treadmill walking (AGTW) program on knee pain and function in obese older adults with knee OA. The alternate hypothesis was that there would be a difference between Knee Injury and Osteoarthritis Outcome Score (KOOS) results before and after the anti-gravity treadmill walking program.
A group of 25 participants with a mean (SD) age of 64.2 (6.1) years and BMI of 33.0 (6.8) kg/m2 completed AGTW twice per week for 12 weeks at a body weight percentage that minimized knee pain. Knee symptoms and function (KOOS), knee pain during full weight-bearing treadmill walking (FTW), isokinetic quadriceps and hamstring muscle strength, cardiovascular fitness (YMCA submaximal cycle ergometer test), general health status (SF-12), and activity level (average daily pedometer readings) were assessed at baseline and following the completion of the 12-week program using paired t-tests and Wilcoxon signed rank sum tests (α = 0.05). Improvements between baseline and outtake were found in all KOOS subscales, as well as hamstring and quadriceps thigh muscle strength. Knee pain during full FWB and AGTW decreased following the 12-week program. No significant differences were found in cardiovascular fitness, SF-12 scores, or average daily pedometer readings.
The results of this study suggest that anti-gravity treadmill walking increases thigh muscle strength, reduces knee pain, and increases functional capacity during daily activities, including FTW in older, obese individuals with knee OA. Anti-gravity treadmill technology has the potential to improve the health and functional capacity of at-risk knee OA individuals, and advance current methods of rehabilitation and long-term management of chronic symptomatic knee OA.
|
164 |
The Lower Taylor Group: Taylor and Wright Valleys, southern Victoria Land, Antarctica; Paleoenvironmental Interpretations and Sequence StratigraphyO'Toole, Timothy Finn January 2010 (has links)
The Devonian Taylor Group (the lower Beacon Supergroup), in the Taylor and Wright Valleys, southern Victoria Land (SVL), Antarctica, is separated from basement by a regional nonconformity, the Kukri Erosion Surface. Thereafter the Taylor Group sediments, observed in this thesis, are affected by two localized unconformities; the Windy Gully Erosion Surface, separating the Terra Cotta Siltstone Formation (TCzst) and older units from the younger overlying New Mountain Sandstone; and the Heimdall Erosion Surface (HES), separating the New Mountain Sandstone Formation (NMSst) and older units from the overlying Altar Mountain Formation. The depositional environments of the Windy Gully Sandstone, New Mountain Sandstone and Altar Mountain Formations have long been under debate.
The Kukri Erosion Surface (KES) truncates the crystalline basement and separates the basement rock from the overlying Beacon Supergroup. Interpretation of the erosion surface characteristics and the directly overlying basal conglomerate lithofacies (WG-BCL) suggest a high relief rocky shore platform environment during a sustained and significant relative sea level fall. The environment has been suggested to be similar to what is currently seen on the West Coast, New Zealand today.
The Windy Gully Sandstone Formation directly overlies the KES and consists of a basal conglomerate (WG-BCL) followed by moderately to well sorted tabular and trough cross bedded felds- to subfeldsarenites. At one location an interbedded siltstone and cross bedded sandstone lithofacies was observed and interpreted as a tidal flat. Overall interpretation of the WGSst suggests continued progradation from a rocky shore platform (WG-BCL) to a series low angle beach, to shallow marine, and back to low angle beach environments. This occurred during a relative sea level rise. Shallowing of the water column produced a gradational relationship with the Terra Cotta Siltstone Formation (TCzst).. The fine to very fine sandy mottled, well laminated siltstones moving to very fine fissile dark siltstones suggest a progression from sandy estuarine to a mud flat environment. The Terra Cotta Siltsone is truncated by the Windy Gully Erosion Surface
The Windy Gully Erosion Surface is observed in the Handsley Valley by the presence of TCzst rip-up clasts in the directly overlying New Mountain Sandstone Formation. Elsewhere the horizon is either very sharp or has desiccation cracks present suggesting a cessation of deposition and subaerial exposure respectively. This suggests a small relative fall in sea level with only localized erosion.
The New Mountain Sandstone Formation (NMSst) predominantly consists of a series of low angle tabular and higher angle trough cross beds. It has a subfeldsarenite base that progressively becomes a pure quartz arenites. Interpretation suggests an initial beach environment with rejuvenated sediments moving to quartzose shallow marine and back to beach environments. This represents a relative sea level rise with continued progradation
The NMSst is truncated in the north by the HES forming a characteristic saw tooth pattern in the cross bedded sandstones; elsewhere the HES is represented by a feldspathic influx moving into the Altar Mountain Formation. The HES was formed due to a significant relative sea level fall leading to exposure and erosion of lithified NMSst cross beds in the north but continuation of deposition in the south.
The Altar Mountain Formation consists of tabular and trough cross bedded subfields- to feldsarenites. The Odin Arkose Member directly overlying the HES is a granule to cobble conglomerate in the north where the HES is erosional and very coarse sand to granule feldsarenite in the south where the HES is conformable. This has been interpreted as a pebbly shore platform to coarse sandy to granular beach environment. The following Altar Mountain Formation is interpreted as a continuation of medium to coarse sandy beach environments with influxes of coarser sediments and possibly moving into shallow marine in places.
Sequence stratigraphy identifies three stratigraphic sequences: S1, the Windy Gully Sandstone and Terra Cotta Siltstone Formations; S2, the New Mountain Sandstone Formation; and S3, the Altar Mountain Formation. The first two sequences (S1&S2) show a clear progression through transgression to a high stand systems tract through regression to a low stand systems tract. The Altar Mountain Formation follows a very similar trend but due to the lack of time and data the above measures have been speculated.
Zircon age dating suggests the source of the sediments in the area come from the Neoproterozic Skelton Group and the DV2a Granite Harbour Intrusives, both directly underlying the sandstones but are exposed elsewhere in SVL. Laminated sandstone clasts within the New Mountain Basal Conglomerate Lithofacies (NM-BCL) are suggested to be sourced from recycled sediments directly below. Other exotic clasts are also observed in the lithofacies are of unknown origin.
|
165 |
Efficient Evaluation of Set ExpressionsMirzazadeh, Mehdi January 2014 (has links)
In this thesis, we study the problem of evaluating set expressions over sorted sets in the comparison model. The problem arises in the context of evaluating search queries in text database systems; most text search engines maintain an inverted list, which consists of a set of documents that contain each possible word. Thus, answering a query is reduced to computing the union, the intersection, or a more complex set expression over sets of documents containing the words in the query.
At the first step, for a given expression on a number of sets and the sizes of the sets, we investigate the worst-case complexity of evaluating the expression in terms of the sizes of the sets. We prove lower bounds and provide algorithms with the matching running time up to a constant factor. We then refine the problem further and design an algorithm that computes such expressions according to the degree by which the input sets are interleaved rather than only considering sets sizes. %We prove the running time of our algorithm is asymptotically optimal. We prove the optimality of our algorithm by way of presenting a matching lower bound sensitive to the interleaving measure.
The algorithms we present are different in the set of set operators they allow in input expressions. We provide algorithms that are worst-case optimal for inputs with union, intersection, and symmetric difference operators. One of the algorithms we provide also supports minus and complement operators and is conjectured to be optimal when an input is allowed to contain these operators as well. We also provide a worst-case optimal algorithm for the form of problem where the input may contain "threshold'" operators, which generalize union and intersection operators: for a number t, a t-threshold operator selects elements that appear in at least in t of the operand sets. Finally, the adaptive algorithm we provide supports union and intersection operators.
|
166 |
The influence of proprioception, balance and plyometric strength on the occurrence of lower leg injuries in schoolboy rugby players / Johannes Hendrik SerfonteinSerfontein, Johannes Hendrik January 2006 (has links)
Background: Rugby injuries are a common phenomenon. The aim of medical professionals is to treat these injuries to the best of their abilities, and if possible, to help prevent their occurrence. Bahr and Holme (2003) argue that sports participation carries with it a risk of injury, with the even more weighty issue that it might later even lead to physical disability. Junge, Cheung, Edwards and Dvorak (2004) recommends the development and implementation of preventative interventions to reduce the rate and severity of injuries in Rugby Union. The Medical and Risk Management Committee of USA Rugby (2003) also reports that the key to preventing injuries in any sport is identifying and addressing the risk factor associated with it. Various studies have identified weakness in plyometric strength, proprioception arid balance as - of lower leg and ankle injuries (Margison, Rowlands, Gleeson arid Eston, 2005; Stasiwpoulos, 2004; Verhagen, Van der Beck, Twisk, Bahr and Mechelen, 2004; Baltaci & Kohl, 2003; Mlophy, Conaoly and Beynnon, 2003; Moss, 2002; Anderson).
Aims: ThE aim of this study was to investigate the influence of proprioception, balance and plyometric strength on the occurrence of lower leg injuries in schoolboy rugby players. A further aim was to develop a preventative training programme to address these variables, should they prove to have an influence on lower leg injuries. The possible inclusion of these tests in talent identification test batteries will also be examined.
Design: A prospective cohort study.
Subjects: A group of 240 schoolboys in U/14, U/15, U/16 and U/18 age groups in two schools (Hoër Volkskool Potchefstroom ("Volkskool") and Potchefstroom Boys High School ("Boys High")) in the North West Province of South Africa was used as the test cohort.
Method: At the beginning of the 2006 rugby season all players were tested for proprioception, balance and plyometric strength. These tests were conducted using a computerised tilt board for proprioceptive testing; Star Excursion Balance Test for Balance and an electronic timing mat for plyometric strength. During the season, weekly injury clinics were held at both schools to document all injuries that occurred following the preceding weekend's matches. A statistical analysis was done on all the data collected from the test batteries and injury clinics. Descriptive statistics (means, standard deviation, minimum and maximum) were used as well as practical significant differences (d-values) (Cohen, 1988). The ratios for left and right leg plyometric strength to bilateral plyometric strength (L+R/Bil) and individual left and right leg plyometric strength to bilateral plyometric strength (L/Bil and R/Bil) were also calculated.
Results: A profile of proprioception, balance and plyometric strength was compiled for schoolboy rugby players using the test data The U/18 players generally bad the best test results of all the age groups, outperforming U/14, U/15 and U/16 players with most tests. U/15 players outperformed both U/14 and U/16 players. Backline players performed better than loose forwards and forwards in plyometric tests in most age groups. Loose-forwards also outperformed tight-forwards with plyometrics at most age groups. At U/15 and U/16 level, tight-forwards slightly outperformed loose-forwards with Star Excursion Balance Tests. Generally, A-teams performed better than B-teams with all the tests except L+R/Bil; L/Bil and R/BiI. The difference between the teams, however, only had a small to medium effect and cannot be considered practically significant. At U/14 and U/15 levels, there were more practically significant differences between the A- and B-teams, with A-teams outperforming B-teams. The tests could have some value for talent identification at this age level.
A rugby epidemiological study was done on the data collected in the weekly injury clinics. This study recorded 54 injuries at the two schools involved during the 2006 season from April to July. Two hundred and forty players were involved in 10890 hours of play. Eight thousand nine hundred and ten of these player hours were practices and 1980 were match hours. These injuries occurred at a prevalence rate of 4.96/1000 player hours. Match injuries accounted for 77.78% of all injuries with
training sessions resulting in the remaining 22.22% of injuries, with a match injury rate of 1 injury per individual player every 3.14 matches. U/14 players showed an overall match injury rate of 11.11/1000 match hours. U/15 players showed a rate of 2.47/1000 match hours. The low rate may be attributed to underreporting of injuries by the U/15 players. U/16 players showed a late of 22.33/1000 hours, while U/18 players showed an exceptionally high rate of 45/1000 match hours. The tackle situation was responsible for the highest percentage of injuries (57.14%). Boys High presented with more injuries (57.4%) than Volkskool at a higher prevalence rate (5.60/1000 player hours). In a positional group comparison, backline players presented with 51.85% of injuries. Since backline players only present 46.7% of players in a team, this shows that backline players have a higher risk of injury. A-team players presented with 66.6% of injuries at a prevalence rate of 6.37/1000 player hours. B-team players had an injury rate of 3.43/1000 player hours. The test values for the players suffering lower leg injuries were compared to those for uninjured players. There were eight players with nine lower leg injuries: one player had injuries of both legs. Six of the injuries were intrinsic of nature and two players had extrinsic injuries. Test values for all five tested players with intrinsic injuries were weaker by a high practically significant margin for the L+R/Bil ratio.
Conclusion: L+R/Bil proved to be the test result with the most influence on the occurrence of intrinsic lower leg injuries. When the individual test results for the players with intrinsic injuries are compared to the percentiles for all players, it becomes visible that the injured players fall in the 20th percentile for both L+R/Bil and Injured leg/Bil ratios. These 20th percentile values could thus be used as a standard for determining the possible occurrence of intrinsic lower leg injuries. These 20th percentile values are 1.012 for R+L/Bil ratios; 0.483 for L/Bil ratios and 0.492 for R/Bil ratios.
This study shows that plyometric ratios for L+R/Bii, L/Bil and R/Bil have an influence on lower leg injuries in schoolboy rugby players. Proprioception and balance did not have any practically significant effects on the occurrence of these injuries. A preventative training programme was also designed following a study of the literature, combined with these results. The tests could also possibly be integrated in talent identification test batteries at U/14 and U/15 level. / Thesis (M.Ed.)--North-West University, Potchefstroom Campus, 2007
|
167 |
The relationship between knee pain and body weight in early onset knee osteoarthritisTakacs, Judit 14 July 2011 (has links)
Osteoarthritis (OA) is a group of diseases entailing degradation of joints, and has been designated as one of the key conditions for special attention during the World Health Organization’s Bone and Joint Decade (2000-2010) (Brooks & Hart, 2000).
Research has demonstrated that body weight is the number one modifiable risk factor associated with the onset and progression of knee OA (Felson, 1996). However, exercise programs that aim to initiate weight loss and improve pain and function in knee OA often increase loading on the knee joint, contributing to degeneration of the knee and progression of the disease (Miyazaki et al, 2002). The introduction of a new anti-gravity treadmill, which utilizes a technology called Lower Body Positive Pressure (LBPP), allows the examination of the relationship between weight, knee pain and knee loading via knee acceleration during exercise. The null hypothesis states that there will be no significant difference in knee pain, knee function and knee joint acceleration when comparing full weight bearing and LBPP treadmill walking exercise in a young knee OA population.
Twenty-two overweight/obese patients with mild or moderate early-onset knee OA were recruited to complete two 25 minute treadmill walking sessions (one full weight-bearing and one LBPP walking session) one week apart and two walkway walking sessions. Knee pain and knee acceleration were recorded. Paired t-tests and ANOVAs were used to compare conditions. On average, an LBPP of 12.3% body weight reduction reduced knee pain in our population. Knee pain was significantly lower during LBPP walking than during full weight-bearing walking. Knee acceleration decreased with increasing LBPP. Heel strike and toe-off data from walkway walking trials illustrated significantly different knee acceleration about the knee (slow walking loads were lower / fast walking were higher), as compared to treadmill walking sessions. This study illustrates that treadmill walking at a minimal level of LBPP can decrease knee pain and attenuate knee joint loads while allowing patients to complete exercise programs aimed at initiating weight loss and improving pain and function in knee OA. LBPP appears to be a promising tool for rehabilitation for those with painful knee OA and other lower body musculoskeletal conditions.
|
168 |
Managing knee osteoarthritis: the effects of anti-gravity treadmill exercise on joint pain and physical functionChristian, Mathew 28 August 2012 (has links)
Knee osteoarthritis (OA) is a degenerative joint condition characterized by progressive joint pain, swelling, and loss of muscle and joint function for which there is no known cure. Current research indicates that the most important modifiable risk factor for the development and progression of knee OA is obesity, a condition that is increasingly common in older adults. Established treatment guidelines for knee OA recommend regular exercise for disease management. However, for obese patients weight-bearing exercise elicits large joint forces that can exacerbate symptoms and influence disease progression. Using a new anti-gravity treadmill capable of generating a lifting force called lower body positive pressure (LBPP), obese patients with knee OA can engage in regular physical activity while minimizing joint loading. The aim of this study was to assess the effect of a 12-week, anti-gravity treadmill walking (AGTW) program on knee pain and function in obese older adults with knee OA. The alternate hypothesis was that there would be a difference between Knee Injury and Osteoarthritis Outcome Score (KOOS) results before and after the anti-gravity treadmill walking program.
A group of 25 participants with a mean (SD) age of 64.2 (6.1) years and BMI of 33.0 (6.8) kg/m2 completed AGTW twice per week for 12 weeks at a body weight percentage that minimized knee pain. Knee symptoms and function (KOOS), knee pain during full weight-bearing treadmill walking (FTW), isokinetic quadriceps and hamstring muscle strength, cardiovascular fitness (YMCA submaximal cycle ergometer test), general health status (SF-12), and activity level (average daily pedometer readings) were assessed at baseline and following the completion of the 12-week program using paired t-tests and Wilcoxon signed rank sum tests (α = 0.05). Improvements between baseline and outtake were found in all KOOS subscales, as well as hamstring and quadriceps thigh muscle strength. Knee pain during full FWB and AGTW decreased following the 12-week program. No significant differences were found in cardiovascular fitness, SF-12 scores, or average daily pedometer readings.
The results of this study suggest that anti-gravity treadmill walking increases thigh muscle strength, reduces knee pain, and increases functional capacity during daily activities, including FTW in older, obese individuals with knee OA. Anti-gravity treadmill technology has the potential to improve the health and functional capacity of at-risk knee OA individuals, and advance current methods of rehabilitation and long-term management of chronic symptomatic knee OA.
|
169 |
Back to the future, for better or worse? Meanings of marriage for young women in the Lower Hunter Region, AustraliaKirby, Emma January 2009 (has links)
Research Doctorate - Doctor of Philosophy (PhD) / Why do young women still choose to marry in the new millennium? Although conjugal diversity in Australia has increased and crude marriage rates have decreased, the majority of young women still desire marriage. Marriage clearly remains important. The institution of marriage, despite high divorce rates, continues to exist as the most powerful and widely acknowledged form of social contract. Few empirical studies have focused on the meanings young women ascribe to marriage. Rather, marriage tends to be regarded as a stable concept around which to research and investigate. The meanings and definitions of marriage, particularly how young people identify marriage within their wider identity, has been ignored in much of the literature. This acceptance of marriage and its meaning within existing literature universalises and reinforces marriage as a dominant social and societal norm, whereby prestige is attached across cultures and through time. Marriage has sustained its centrality within social science research, yet without justification or adequate problematising. Meanwhile, in gender studies there is a tendency to assume that marriage is an outdated concept which has been superseded by the sexual revolution and by second wave feminism. As a result, feminist studies have not addressed the apparent persistence of marriage as a goal for young women. This thesis project contributes to filling that identified gap by addressing the apparent persistence of marriage as a goal for young women in Australia. This mixed methods study maintains a focus on qualitative methodologies and feminist epistemologies, aiming to provide rich subjective accounts of marriage. The study comprises data from 225 surveys. It also includes data from in-depth semi-structured interviews and focus group discussions with 75 of the survey participants. All three kinds of data collection asked about the meanings of marriage for young women. The participants were women aged 18 to 35 years, of various relationship statuses, from the Newcastle and Lower Hunter region of New South Wales, Australia. Participants were purposefully sampled to allow a spread of age and relationship status. Although this was not specifically intended, as a cohort they can be described as predominantly white and middle class. A grounded theory approach in line with Glaser and Strauss (1967) was employed to uncover subjective narratives that revealed attitudes and feelings towards the place of marriage and intimate relationships in the young women’s life trajectories. The findings of this study result from descriptive statistical analysis of survey data, and from content and discourse analysis of interviews and focus groups that indicate participants’ discursive constructions of marriage. The study finds that participants position marriage as a marker of status, as important for child bearing, as well as the major factor in achieving a competent and legitimate mature feminine identity. This study presents an overview of young Australian women’s aspirations for, and experiences of marriage and intimate relationships. It offers fresh insights into the ways these women imagine marriage and the marital relationship within their life trajectory. An integrated account of feminist critiques of marriage, and theorising on individualization and detraditionalization, allows us to see how gender inequalities are maintained in marital relationships under the discourse of individualization. This study offers evidence that emphasises the need for continuing feminist critiques of marriage and the family. The findings of this study suggest that the neo-liberal discourse of individualization has encouraged of the idea of gender neutrality, equality and autonomy within the marital relationship. At the same time the young women indicate that they expect to put the interests and wishes of a future husband ahead of their own. High levels of personal compromise are foreshadowed. Yet their imagined futures include more than marriage. They do wish for self-fulfilment and many want careers. However, marriage is constructed as the anchoring status and identity that makes those goals legitimate and achievable. The study finds evidence of both detraditionalization and retraditionalization trends in the aspirations, expectations and lived realities of the young women interviewed. It is argued that attitudes towards marriage reflect the detraditionalization process to some extent, yet concurrently indicate the retraditionalization process; for example in the desire for full church weddings and in the defence of women taking responsibility for housework and raising children.
|
170 |
Anti-pronation tape: Initial effects on neuromotor control of gait, foot posture and foot mobility and the influence of continual useMelinda Franettovich Unknown Date (has links)
Anti-pronation taping is commonly used by clinicians in the management of lower limb musculoskeletal pain and injury. Despite its frequent use in the clinical setting the mechanism(s) underlying its efficacy is not completely understood. For example, there is evidence that anti-pronation taping produces a biomechanical effect, but there has been little investigation of other mechanisms such as neurophysiological or psychological effects. Additionally, studies to date have been performed in mostly asymptomatic populations and have focused on the initial effect of tape (i.e. immediately following application and through a short duration of activity). Improved understanding of the underlying physiological mechanism(s) of anti-pronation tape is likely to facilitate improved knowledge of the technique, which may optimise its clinical application and contribute to clinical selection guidelines. The aims of this thesis were developed to address several of the limitations in the current anti-pronation taping literature. To facilitate an investigation of the comparative initial physiological effect of anti-pronation tape in a symptomatic and asymptomatic population, the first aim of this thesis was to compare neuromotor control (control of muscle activation and movement patterns) of gait, foot posture and foot mobility between asymptomatic individuals and individuals with a history of exercise related leg pain. The second aim of this thesis was to investigate the initial physiological effects of anti-pronation tape, specifically its neurophysiological (i.e. effect on muscle activation patterns) and biomechanical (i.e. effect on movement patterns, foot posture, foot mobility) effects. Thirdly this thesis aimed to investigate the duration of these initial physiological effects following tape removal. The fourth and fifth aims were to investigate the long term biomechanical and neurophysiological effects of anti-pronation taping i.e. following continual use over a clinically relevant period. In the first instance our aim was to investigate the effect of continual use on neuromotor control of gait, foot posture and foot mobility, and secondly to investigate the effect of continual use on the technique’s initial neurophysiological and biomechanical effects. Individuals with exercise related leg pain demonstrated lower activation of gluteus medius and lateral gastrocnemius during gait, but we observed no differences in lower limb movement patterns or foot posture and foot mobility between the two groups. The initial effect of tape was similar in individuals with and without exercise related leg pain. Specifically application of tape produced a reduction in activation of tibialis posterior, tibialis anterior and medial gastrocnemius, and increased activation of peroneus longus. There was a reduction in foot mobility, ankle plantarflexion and abduction excursion and an increase in ankle dorsiflexion and adduction excursion. Reduced muscle activation and increased motion was also observed at more proximal segments (knee, hip, pelvis), but were of smaller magnitude than at the foot and ankle. Changes in foot mobility, ankle kinematics and leg muscle activity did not continue following the removal of tape, but at more proximal segments (i.e. pelvis, hip and knee) small changes in kinematics and muscle activity were observed following the removal of tape. In regards to long term effects, continual use of tape for approximately 12 days produced a small increase in arch height when compared to a control. We did not observe a change in muscle activation or motion patterns, nor did continual use of the technique influence its initial neurophysiological or biomechanical effects (i.e. reduction in muscle activity, reduction in foot mobility, altered lower limb motion). The studies from this thesis provide evidence that anti-pronation tape should be considered in the management of individuals where reduced midfoot mobility, control of ankle motion or reduced activation of the leg muscles is desired, regardless of symptomatic status. When applied for approximately 12 days, anti-pronation tape produced a small increase in arch height ratio, but no alteration in neuromotor control. We are not aware of any definitive data on what constitutes a clinically meaningful increase in arch height, but results from a published case series suggests that our findings of a small increase in arch height may be clinically relevant for the treatment of lower extremity overuse injuries. Continual use of tape for a clinically relevant period does not alter its initial effects on foot posture and mobility or neuromotor control during gait. It would appear that the initial effects of anti-pronation tape are robust even after continuous use over a period of 11 days.
|
Page generated in 0.0472 seconds