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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
271

The Effects of Whole Body Vibration Platform Training on Hamstring Flexibility

Epperson, Travis A. 04 August 2009 (has links) (PDF)
Introduction: Very few studies have looked at the effect of vibration on flexibility, and no studies exist that have looked at stretching concurrently with whole body vibration (WBV) training. Therefore, the purpose of this study was to determine if whole-body-vibration training (WBV) done concurrently with static stretch (SV) is more effective than static stretching alone (SS), and to see if WBV training independently (SQ) improves hamstring flexibility without stretching. A secondary purpose of this study is to determine if retention of flexibility gains are maintained. Methods: Forty-four subjects (31 men, 13 women) completed this study (age 22.5 ± 1.8 years; body mass 75.54 ± 13.18 kg; height 176.7 ± 8.06 kg). All subjects were randomly assigned to 1 of 5 groups: SV group (8 males, 3 females), SQ group (8 m, 4 f), SS group (8 m, 3 f), and the C group (7 m, 3 f). All subjects were measured bilaterally for hamstring flexibility using the lying passive knee extension test (LPKE) prior to group assignment. Subjects from each treatment group reported to lab 5 times per week for treatment. Subjects stood on the WBV platform for 5 repetitions of 30-seconds at with 30-seconds in between bouts. The SV group stretched hamstrings while standing on the WBV during the vibration bouts (at 26 Hz and 4 mm amplitude). The SS group did the same thing except the unit was not turned on. The SQ group stood on the WBV platform in a semi-squat position similar to most WBV training studies, without stretching, but with vibration. The C group stood on the WBV platform in a semi-squat without vibration. Analysis and Results: A mixed models analysis of covariance (ANCOVA) was used while blocking on subjects to analyze data using the statistical program SAS (version 9.1). A Bonferroni correction was used for significance on all post hoc tests (p<.0001). At baseline there were no significant differences between groups for flexibility (see Table 1), showing that each group was similar in flexibility to start. Throughout the treatment period (3 weeks of stretching) both the SS and SV groups had significant increases in flexibility compared to SQ and C. Analysis of the slopes (rate of change) for the treatment period was significantly different between the SV group and all other groups (p<.0001 for all comparisons), showing that the SV group had a greater rate of change than all other groups. For the retention period there was no significant difference between the SV and SS group (p=0.0455), but there was a significant difference between both the SV and SS groups and all other groups (p<.0001 for all comparisons). Conclusion: Stretching during WBV improves flexibility more than static stretching alone and at a faster rate. WBV on its own without stretching does not significantly improve hamstring flexibility.
272

The Effects of Whole Body Vibration on Dorsiflexion in Chronic Ankle Instability

Thalman, Lesley Abigail 09 December 2011 (has links) (PDF)
BACKGROUND: Whole body vibration (WBV) platforms are currently used as adjunctive training devices for exercise programs, and have been shown to facilitate flexibility. One of the biggest contributing factors to chronic ankle instability (CAI) is the lack of dorsiflexion after lateral ankle sprains and WBV may be an effective way to increase range of motion in this population. PURPOSE: Determine if WBV done concurrently with static stretching (SS) is more effective then SS alone in improving dorsiflexion ROM in subjects with CAI. METHODS: Subjects were divided into 3 groups (control, static stretch, and static stretch and vibrate). Subjects stretched 4 days/wk for 3 wks for 4 sets of 30 seconds alternating 2 different positions to stretch both the soleus and the gastrocnemius. Imposed vibration at 34 Hz 2mm during the stretches for the stretch group. ANALYSIS: Repeated measures ANOVA was performed using SPSS (version 19), with post-hoc Tukey tests as needed (p<.05). RESULTS: In both the straight and bent leg position, a significant group x time interaction was found for dorsiflexion range of motion. Post hoc tests revealed significance in the SV group between pre-tx and post-tx 1 and pre-tx and post-tx 2. No statistical significance was found between post-tx 1 and post-tx 2 in the SV group or at any time in the N or SS group. DISCUSSION: Static Stretching with vibration increases dorsiflexion ROM in subjects with CAI better than static stretching alone.
273

On the Effective Flexibility of Immersed Undulatory Swimmers

Labosky, Vincent J. 05 August 2022 (has links)
No description available.
274

Bioenergetic Implications of the AMPKg3 R225W Mutation in Human Muscle

Hadzimustafic, Nina 11 August 2020 (has links)
AMPK is a master regulator of cellular energy homeostasis. The gain-of-function AMPKg3 R225W mutation in human skeletal muscle increases resistance to fatigue during exercise, mitochondrial content, and glycogen storage. We demonstrate that primary myotubes exhibit increased OCR, decreased ECAR, increased FAO, and increased activities of several mitochondrial complexes. To examine whether functional effects are attributable to mitochondrial content, we inhibited AMPK; differences between R225W and control were diminished. Glycogen phosphorylase inhibition demonstrated normal respiration independent of glycogen. We examined markers of quality/quantity control of mitochondria. In R225W muscle, fusion markers increased, biogenesis markers remained unchanged, mTOR pathway was inhibited, and there was greater capacity for autophagic flux and mitophagy. We thus determine that bioenergetic effects of R225W are in part due to active AMPK, but also due to capacity for more robust mitochondria. Overall, R225W provides a model for evaluating effects of AMPK, and new avenues toward treatment of metabolic disease.
275

Inskolning i förskolan

Bugajski, Agnieszka January 2013 (has links)
No description available.
276

Mental Health Effects of Applied Mental Health Courses vs. Non-Course Controls on Depressive Symptoms and Psychological Flexibility

Diopulos, Madeline Jane Cope 14 August 2023 (has links) (PDF)
This study aims to evaluate the effectiveness of an applied mental health course in a university setting in reducing distress and symptoms of depression and increasing levels of psychological flexibility. As university psychological services are unable to meet the need of their students, other methods of treatment must be explored. Participants in the study are comprised of those who chose to enroll in a student development course aimed at increasing psychological flexibility and introducing basic psychoeducation as well as various university students who elected to participate. Depressive symptoms and psychological flexibility were measured pre-, mid-, and twice post-test in both the experimental and control groups. Split-plot Analysis of Variance and Covariance were conducted to explore outcomes. Results suggest that the psychoeducational course effectively reduces symptoms of depression and levels of psychological flexibility were increased for participants within the course. However, levels of distress were not significantly affected by the course. Further research to increase generalizability and affirm results is necessary.
277

Behavioral and Hormonal Flexibility Across Light Environments in Guppies (Poecilia reticulata)

Walz, Julia C 01 August 2014 (has links) (PDF)
Behavior may be dramatically influenced by changing environments, and differences in light intensity environments may have important behavioral consequences. One approach to understanding changes in behavior is by studying behavioral syndromes, suites of correlated behaviors reflecting between individual consistencies in behavior expressed within a behavioral situation (e.g., correlations between antipredator behaviors in different habitats), or across behavioral contexts (e.g., correlations among feeding, antipredator, or mating behavior) (Sih et al. 2004a). Guppies (Poecilia reticulata) provide a great model system to study behavior. Guppies are small, freshwater tropical fish that inhabit still pools in swift-flowing streams, and the backwaters of small rivers in mountain forest areas of Trinidad (Houde 1997; Magurran 2005). In this study I attempted to answer the following questions using three low predation populations of guppies : 1) Do guppies display a behavioral syndrome for aggression and/or courtship across light situations?; 2) Are there mean level changes in aggression or courtship across light situations?; 3) Are mean level changes influenced by differing social environments that include or lack sexually receptive females?; 4) Are there correlations between behavior and the androgen hormones testosterone and 11-ketotestosterone?; 5) Are there correlations between behavior and the stress hormone cortisol?; 6) Are there mean level changes in hormone release rates across light environments?; and 7) Is flexibility in hormone release rates influenced by social environments that include or lack sexually receptive females? Guppies exhibit behavioral syndromes for both aggression and courtship. Furthermore, guppies exhibit behavioral flexibility for both aggression and courtship, but only in social environments that include sexually receptive females. I found no correlations between behavior and androgen hormones. I also did not find any correlations between behavior and the stress hormone cortisol. Furthermore, I did not find any mean level changes in hormone release rates across light environments. Interestingly, cortisol levels were higher in social environments in which sexually receptive females were absent. Many studies have looked at how the environment influences courtship behavior in guppies, especially employing high predation populations, but few studies have examined aggressive behavior or behavior in general with low predation populations. Furthermore, few studies have determined the role social environments play, and how hormones may interact with behavior. This study is important because it helps illuminate how low predation populations deal with changes in light intensity environments, and adds to what we understand about guppy behavior in general.
278

Vibration Measurement Based Damage Identification for Structural Health Monitoring

Bisht, Saurabh Singh 14 January 2011 (has links)
The focus of this research is on the development of vibration response-based damage detection in civil engineering structures. Modal parameter-based and model identification-based approaches have been considered. In the modal parameter-based approach, the flexibility and curvature flexibility matrices of the structure are used to identify the damage. It is shown that changes in these matrices can be related to changes in stiffness values of individual structural members. Using this relationship, a method is proposed to solve for the change in stiffness values. The application of this approach is demonstrated on the benchmark problem developed by the joint International Association of Structural Control and American Society of Civil Engineers Structural Health Monitoring task group. The proposed approach is found to be effective in identifying various damage scenarios of this benchmark problem. The effect of missing modes on the damage identification scheme is also studied. The second method for damage identification aims at identifying sudden changes in stiffness for real time applications. It is shown that the high-frequency content of the response acceleration can be used to identify the instant at which a structure suffers a sudden reduction in its stiffness value. Using the Gibb's phenomenon, it is shown why a high-pass filter can be used for identifying such damages. The application of high-pass filters is then shown in identifying sudden stiffness changes in a linear multi-degree-of-freedom system and a bilinear single degree of freedom system. The impact of measurement noise on the identification approach is also studied. The noise characteristics under which damage identification can or cannot be made are clearly identified. The issue of quantification of the stiffness reduction by this approach is also examined. It is noted that even if the time at which the reduction in stiffness happens can be identified, the quantification of damage requires the knowledge of system displacement values. In principle, such displacements can be calculated by numerical integration of the acceleration response, but the numerical integrations are known to suffer from the low frequency drift error problems. To avoid the errors introduced due to numerical integration of the acceleration response, an approach utilizing the unscented Kalman filter is developed to track the sudden changes in stiffness values. This approach is referred to as the adaptive unscented Kalman filter (AUKF) approach. The successful application of the proposed AUKF approach is shown on two multi-degree of freedom systems that experience sudden loss of stiffness values while subjected to earthquake induced base excitation. / Ph. D.
279

The Nexus Between Cognitive Flexibility and Prejudicial Attitudes in Younger and Older Adults

Germosen, Yerika 01 January 2019 (has links)
The mutability of prejudicial attitudes can be elucidated by taking into account the declines in cognition that tend to emerge as we age. This study aimed to assess whether there is a relationship between prejudice towards different ethnic groups and cognitive flexibility throughout adulthood. Ninety-five older adults and 118 younger adults were asked to complete an electronic survey encompassing measures of cognitive flexibility, social desirability, personality, optimism, empathy, ethnic attachment and prejudice. It was hypothesized that older adults would report lower levels of cognitive flexibility and higher levels of ethnic attachment in comparison to younger adults, which would in turn make the inverse relationship between cognitive flexibility and prejudice stronger in older participants. The results did not support the hypotheses predicting that there would be cohort differences in cognitive flexibility and ethnic attachment. As expected, there was a negative correlation between prejudice and cognitive flexibility, but it was only significant in younger adults before controlling for the influence of social desirability. Additionally, regression models predicting prejudice based on cognitive flexibility and ethnic attachment were significant before and after controlling for social desirability, but only in younger adults. Exploratory analyses indicate that the strength of the correlations between all study variables were generally lower in older adults. The findings presented here raise an argument for evaluating how the interplay between prejudice and cognitive flexibility may change in the later stages of life.
280

Dynamic substructuring by the boundary flexibility vector method of component mode synthesis

Abdallah, Ayman Ahmed January 1990 (has links)
No description available.

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