Fiber-metal laminates (FML) are the advanced materials that are developed to improve the high performance of lightweight structures that are rapidly becoming a superior substitute for metal structures. The reasons behind their emerging usage are the mechanical properties without a compromise in weight other than the traditional metals. The bond remains a concern. This thesis reviews the effect of pre-treatments, say heat, P2 etch and laser treatments on the substrate which modifies the surface composition/roughness to impact the bond strength. The constituents that make up the FMLs in our present study are the Aluminum 2024 alloy as the substrate and the carbon fiber prepregs are the fibers. These composite samples are manufactured in a compression molding process after each pre-treatment and are then subjected to different tests to investigate its properties in tension, compression, flexural and lap shear strength. The results indicate that heat treatment adversely affects properties of the metal and the joint while laser treatments provide the best bond and joint strength.

Call number: LD2668 .T4 1978 N57 / Master of Science

Background Long life does not inevitably mean more healthy years; older women have an increased risk of disabilities, diseases and adverse life events. Nevertheless, many older women experience health. This may be explained by possessing resources that promote health, despite adversities. Inner strength is seen as a resource as such. In this thesis inner strength is interpreted according to a theoretical model where inner strength comprises four interrelated and interacting dimensions: connectedness, creativity, flexibility and firmness, and being rated by the Inner Strength Scale (ISS). Aim and methods The overall purpose of this thesis was to explore inner strength as a health resource among older women. In study I six focus group interviews were performed with older women (66-84 years; n = 29) and the interviews were analysed by a concept driven approach and by means of qualitative content analysis. Studies II–IV had a quantitative, cross-sectional design. A questionnaire was sent to all older women (65 years and older) living in Åland, an autonomous island community in the Baltic Sea, and 1555 (57%) women responded. The data was analysed using descriptive and inferential statistics. Results In study I, exploring how inner strength and its dimensions can be identified in narratives of older women, connectedness was interpreted as a striving to be in communion, creativity as the ability to make the best of the situation, firmness as having a spirit of determination – “it is all up to you”, and flexibility as a balancing act. The results of study II showed that strong inner strength was associated with better mental health, but not physical health. In exploring factors associated with health-related quality of life, fewer symptoms of depressive disorders was the strongest explanatory variable, and together with not feeling lonely associated with better both physical health and mental health. Better physical health was also explained by not having a diagnosed disease, being of lower age and the opportunity to engage in meaningful leisure activities. Better mental health was additionally explained by having enough money for personal needs. In study III the result showed that non-depressed women were likely to have a strong inner strength, as well as never or seldom feeling lonely, taking fewer prescribed drugs, feeling needed and having the opportunity to engage in meaningful leisure activities. In study IV poorer mental health was associated with weaker inner strength in total, and in all four dimensions of inner strength. Symptoms of depressive disorders and feeling lonely were related to lower scores in three of the dimensions (except firmness and creativity, respectively) and poorer physical health was associated with lower scores in two of the dimensions (firmness and flexibility). Some other health threats were significantly associated with only one of the dimensions (connectedness or creativity), and others were not significantly associated at all. Conclusion The results add nuance to the notion of inner strength and deepen empirical knowledge about the phenomenon. It is elucidated that the ISS can be used not only to rate inner strength but also to offer guidance as to the areas (i.e. dimensions) in which interventions may be profitable. It is further shown that inner strengths can be identified in narratives of older women. Mental ill health has shown to have overall the strongest association with weakened inner strength among community-dwelling older women. The causality can, though, not be studied due to the cross-sectional design; therefore, longitudinal studies are recommended. Notwithstanding that limitation, the findings can be used as a knowledge base in further research within this field.

Thesis (M.Tech.: Chiropractic)- Dept. of Chiropractic, Durban University of Technology, 2008. x, 52 leaves, Appendices A-E, [25] leaves. / To determine whether a relationship exists between core stability and bowling speed in Action Cricket bowlers. Methods: Thirty asymptomatic indoor Action Cricket fast and fast-medium bowlers were divided into two groups of 15 each, with Group A having well-developed core stability and group B having poorly-developed core stability. The concept of matched pairs was used for age and cricket experience in order to maintain homogeneity between the groups. The core stability and bowling speed of each participant was measured using a pressure biofeedback unit (PBU) and speed sports radar respectively. SPSS version 15.0 was used to analyse the data.

Dissertation submitted in partial compliance with the requirements for the Master’s Degree in Technology: Chiropractic at the Durban University of Technology, 2009 / Objectives: When we consider the body position of a field hockey player, the lumbar spine is always in a flexed position, which combined with rotational movements during various hitting and pushing techniques, increases the strain upon the spine and surrounding muscles, thus leading to low back pain. To determine the relationship between core strength and trunk extensor endurance relating to the incidence of acute low back pain in field hockey players. Project Design: The research project was in the form of a quantitative cross-sectional study, using human subjects. Setting: The research project occurred during the field hockey season (2008) with players who had acute low back pain. The players were clinically assessed and subdivided into necessary groups at the Chiropractic Day Clinic at the Durban Institute of Technology. Subjects: Adult, male patients, aged between 18 and 30 years of age, playing premier field hockey. Out of the thirty players, 12 players have played in the National u/21 squad, 7 players have played in a Junior National team and 11 players have played senior provincial field hockey. Outcome measure: This included three tests. Firstly, the absolute difference of pressure from the reference value of 70mmHg (prone) and 40mmHg (supine) was used as the outcome measure on a Pressure Biofeedback Unit and length of time (in seconds), a correct contraction of the core stability muscles was maintained. Secondly, the length of time (in seconds) for Trunk Extensor Endurance. Thirdly, repeated measures for NRS-101 and Quebec Back Pain Disability Scale for the duration of the research period. v Results: It was found that there was no statistical evidence or convincing trend to show that the training programmes (core stability and trunk extensor endurance) increased the subjects’ core strength or trunk extensor endurance in the time allocated, although there seemed to be a placebo effect in the Trunk Extensor Group, which showed improvement in some of the core stability outcomes. There was statistical evidence that the intervention (training programmes) reduced pain, according to the Quebec Back Pain Disability Scale (Quebec) score over time, and a non-significant trend suggested this according to the Numerical Rating Scale-101 (NRS). Since both groups’ NRS and Quebec scores were not significantly different at baseline, the difference can be attributed to the effect of the intervention. Conclusions: The results of this study found that the Trunk Extensor Endurance Group, that performed the trunk extensor endurance training programme, yielded better results in core stability and trunk extensor endurance. However, the Core Stability Group, that performed the core stability training programme, showed a quicker reduction in pain levels during the three week intervention period. Therefore, by combining both training programmes, future rehabilitation of athletes suffering from acute low back pain will be more successful. Sport performance of the athletes (field hockey players), through the proponents of swiss ball training, will also improve.

Background: Strength training for children and adolescents was for a long time a controversial subject but is nowadays proven safe and beneficial and recommendations for children’s strength training have been put forward by scientific sports boards in several western countries. Despite that, in Sweden strength training is not very commonly applied in children and adolescent’s sport. Strength training has proven to increase the sports performance and decrease the risk of injuries both in adults and children and would therefore be a good additional training method to the sport-specific training at any age. Different types of strength training have in several studies shown to improve the jumping ability, sprint performance and several other aspects. Purpose: The aim of the present study was to investigate the differences between pre- and post-test for the physical performance test after the 8-week strength training intervention both for the whole training group together and divided by type of intervention. Method: Eighteen adolescent boys were divided in two strength training groups, a friction Flowin® training group (FTR) and a barbell training group (BTR). They were tested pre and post an eight weeks intervention for 5-10-30 m sprint, Agility zig-zag test and two different counter movement jump (CMJ) tests. Result: The 30 m sprint improved after 8 weeks intervention for both groups together (n=18) (p= 0.036). Splitting into groups based on intervention, only the BTR group improved their performance in 30 m sprint after 8 weeks intervention (p=0.036). Both the BTR and FTR decreased their performance in 5 m sprint after the 8-week intervention (BTR p=0.007, FTR p=0.014). There was no statistical significant difference between or within the groups regarding any other tests. Conclusion: Eight weeks of strength training can improve the 30m sprint performance for adolescent male soccer players after 8 weeks intervention. More research is needed to conclude whereas the increase and explosive performance for adolescents are more affected by the duration of strength training or the strength training methods. Keywords: Children, adolescent, strength training, Flowin, barbell, physical soccer performance

Purpose The purpose of this study was to describe the evidence-based research recommendations on injury prevention methods against hamstring injuries among Swedish men's elite team in football. The research-based recommendations was then to be compared with the way Swedish elite football teams work to prevent hamstrings injuries. Method First a literature search of PubMed and SPORTDiscuss was made to find the most evidence-based training methods to hamstring injuries. Then an Internet questionnaire regarding injury prevention training methods against hamstring injuries was sent to all Swedish elite football teams. The answers off the questionnaire was then compared with the research that had the most evidence based training methods to hamstring injuries. Results Research shows that the method with the most evidence is eccentric strength training. Flexibility, static stretch and core stability training is research methods that can be used to prevent hamstrings injuries but these methods lack a large validated research basis. 8 of 32 (25 %) teams answered the questionnaire. All teams indicated that they were working with injury prevention methods but the methods varied from the eccentric strength training to periodization and flexibility training. 2 of 8 teams indicated that they worked with eccentric strength training that is recommended by science as the most evidence-based training method. Conclusion The study shows that the teams partly work after what the research recommends as the most evidence-based training methods against hamstring injuries. However, the study lacks validity and further research is needed before definitive conclusions can be drawn. / Syfte Syftet med denna studie är att beskriva vilka evidensbaserade forskningsrekommendationer som finns kring skadeförebyggande träningsmetoder mot hamstringsskador hos svenska herrelitlag i fotboll. De forskningsbaserade rekommendationerna ska sedan jämföras med arbetssättet hos herrelitlagen i svensk fotboll. Metod Först gjordes en litteratursökning på databaserna PubMed och SPORTDiscuss för att hitta de mest evidensbaserade träningsmetoderna mot hamstringsskador. Sedan skickades en webbenkät angående skadeförebyggande träningsmetoder mot hamstringsskador ut till alla svenska herrelitfotbollslag. Svaren på enkäten speglades sedan mot vad forskningen rekommenderade som de mest effektiva träningsmetoderna mot hamstringsskador. Resultat Forskning visar att den metoden med mest evidens är excentrisk styrketräning. Rörelse/stretch samt bålstabilitetsträning är enligt forskningen metoder som kan användas för att förebygga hamstringsskador men dessa metoder saknar ett stort validerat forskningsunderlag. 8 av 32 (25%) föreningar besvarade enkäten. Alla föreningar angav att de arbetade med skadeförebyggande åtgärder men metoderna varierade från excentrisk styrketräning till periodisering och rörlighetsträning. 2 av 8 föreningar angav att de arbetade med excentrisk styrketräning som forskningen rekommenderar som den mest evidensbaserade träningsmetoden. Slutsats Studien visar att föreningarna delvis arbetar efter vad forskningen rekommenderar som evidensbaserade träningsmetoder mot hamstringsskador. Dock saknar studien validitet och ytterligare forskning behövs för att slutgiltiga slutsatser ska kunna dras.

Background. Handball is a fast paced sport, with high velocity movements performed in a predominantly unilateral plane. In order to make training as specific as possible to on court movements, resistance training programmes should involve exercises that reflect the speed and stance of how they will be performed during gameplay however, working velocities are rarely prescribed due to the lack of research in the area. Aim. The aim of this study was (1) to determine the effect of three different training modes; unilateral high velocity (UHV), bilateral high velocity (BHV) and bilateral slow velocity (BSV) on vertical loaded and unloaded jumps, sprint, agility and balance. (2) To determine if any of these interventions had more of an effect when compared to each other. Methods. 29 women from four teams in the Swedish Elitserien participated in a 16-week intervention study. Teams were assigned to either UHV, who performed unilateral exercises with a high intended movement velocity, BHV, bilateral exercises at a high intended movement velocity, or BSV, who continued their regular bilateral slow velocity training. Power was assessed pre- and post-intervention by loaded vertical squat jump and countermovement jump (CMJ) both unilaterally and bilaterally. Performance assessments were conducted through 20m Sprints, agility T-test and Y-balance test. Effect sizes were calculated to determine the magnitude of differences from pre- to post-intervention in three training modes. One-way ANOVA determined if the group interactions were significant. Results. All three training modes increased their power output to varying levels and effect sizes. The UHV group demonstrated large effect sizes for all improvements in power output, whilst the BHV and BSV groups ranged from trivial to large. UHV got significantly faster at reaching time to peak velocity in unilateral and bilateral measures compared to both BHV and BSV (p=<0.05). Conclusion. The results suggest that a 16-week resistance training intervention regardless of stance improves power however to varying magnitudes. The high velocity groups showed greater improvements in measures of power and performance. This study suggests that resistance training at a high intended movement velocity may be beneficial for improving power and performance in elite women’s handball players.

The aim of this study was to gain a deeper understanding of women’s motivation for strength training,how women's perceptions of gym surroundings have changed and the impact strength training had onwomen's wellbeing. The study was qualitative with eight semi-structured interviews of women betweenthe ages of 35-55 years. The results of the study showed that all the women had developed a differentand more positive view of gym surroundings today than they had when they started lifting weights.Most women also reported that they primarily trained with health in focus, a few described thatappearance was the main motive before but had now changed to health as the main motivation. Inrelation to the wellbeing the results showed that the strength training made the women feel better, feelmore alert and happier.

The common manufacturing process of prosthetic sockets is usually a time- and labor consuming activity. This project’s purpose was to look for alternative manufacturing methods that could speed up the process and enhance the experience for the patient for example make some personal design or make the socket lighter. The main goal was to investigate which properties could be achieved by applying Electron Beam Melting as an alternative manufacturing process for prosthetic sockets by applying an earlier developed methodology. An investigation of earlier scientific works with the keywords (additive manufacturing, free form fabrication, orthopedic, prosthetic sockets and rapid manufacturing) was done as well as gathering knowledge how to operate and handle the machines necessary to carry out the project. An updated version of the methodology was developed where the design was verified using finite element analysis. With the updated version the methodology contained nine steps, which in short was as follows. First apprehend an inner socket from an orthopedic clinic with a pattern drawn up on it, the pattern is then transferred to a computer environment and manipulated to the desired shape and thickness. A compressive strength test, both virtual and experimental, was designed by a modified version of the ISO-10328 standard and the virtual design was verified before the socket was manufactured in the Electron Beam Melting machine. The manufactured socket was tested in the experimental set-up to verify the virtual one. The result was a personal designed socket of Ti6Al4V including the male pyramid for connection and a suspension system, which consisted of an inner socket and a one-way valve. It was concluded that Electron Beam Melting could be used as an alternative manufacturing process of prosthetic sockets.