Satellite Images Show the Movement of Floating _Sargassum_ in the Gulf of Mexico and Atlantic Ocean

The question of the origin, distribution and fate of the floating seaweed _Sargassum_ has fascinated sailors and scientists from the time of Columbus. Observations from ships are hampered by the large and variable area over which _Sargassum_ is dispersed. Here we use satellite imagery to present the first mapping of the full distribution and movement of the population of _Sargassum_ in the Gulf of Mexico and western Atlantic in the years 2002 to 2008. For the first time, we show a seasonal pattern in which _Sargassum_ originates in the northwest Gulf of Mexico in spring of each year, is advected into the Atlantic in about July, appearing east of Cape Hatteras as a "Sargassum jet", and ending northeast of the Bahamas in February of the following year. This pattern appears consistent with historical surveys. Future satellite observations will show whether this pattern repeats in all or most years

Dynamic muscle quality of the plantar flexors is impaired in claudicant patients with peripheral arterial disease and associated with poorer walking endurance

Objective Peripheral arterial disease and intermittent claudication (PAD-IC) negatively affects physical activity and function. There is evidence for plantarflexor muscle dysfunction and weakness; however, the extent to which this dysfunction can be attributed to reduced muscle size or quality, or both, is not yet known. This study investigated whether in vivo plantarflexor muscle quality during static and dynamic contractions is altered by PAD-IC and whether such changes are associated with impaired walking endurance according to initial and absolute claudication distances. Methods The study recruited 22 participants, consisting of 10 healthy controls and 12 claudicant patients with occlusion of the superficial femoral artery (seven unilateral and five bilateral). Muscle quality of the combined gastrocnemius muscles during static contractions was calculated by normalizing the estimated maximal potential muscle force to the physiological cross-sectional area of the lateral and medial gastrocnemius. Muscle quality during dynamic contractions of the combined plantarflexor muscles was calculated as the ratio of peak voluntary concentric plantarflexor power and the summed volume of lateral and medial gastrocnemius. Results Dynamic muscle quality was 24% lower in the claudicating-limb and asymptomatic-limb groups compared with controls (P = .017 and P = .023). The differences were most apparent at the highest contraction velocity (180°/s). Dynamic muscle quality was associated with reduced walking endurance (R = 0.689, P = .006 and R = 0.550, P = .042 for initial and absolute claudication distance, respectively). The claudicating-limb group demonstrated a trend toward reduced static muscle quality compared with controls (22%, P = .084). The relative contribution of the soleus muscle to plantarflexion maximum voluntary contraction was significantly higher in the claudicating-limb and asymptomatic-limb groups than in controls (P = .012 and P = .018). Conclusions The muscle strength of the plantarflexors in those with PAD-IC appears to be impaired at high contraction velocities. This may be explained by some reduction in gastrocnemii muscle quality and a greater reliance on the prominently type I-fibered soleus muscle. The reduced dynamic capability of the plantarflexor muscles was associated with disease severity and walking ability; therefore, efforts to improve plantarflexor power through dynamic exercise intervention are vital to maintain functional performance

Adaptations in plantarflexor muscle-tendon properties and their impact on gait in claudicants with peripheral arterial disease

Peripheral arterial disease (PAD) is a chronic atherosclerotic disease, primarily affecting the lower limbs. The associated intermittent claudication (IC) is a muscle pain/cramping sensation in the legs, primarily brought on by physical activity, such as walking, which can negatively affect daily function and quality of life. Poorer levels of lower-limb muscle strength are strong predictors for mortality and the plantarflexor muscles in particular are a frequent site of claudication pain, with previous literature also indicating their dysfunction during level gait. However, little is known about the size and architecture of these muscles, the quality of the in-series Achilles tendon or the factors that contribute to voluntary joint moments and how these relate to physical function in this population. The aim of this thesis was to determine the functional properties of the gastrocnemii muscles and Achilles tendon in order to make evidence-based clinical recommendations for specific exercise interventions for claudicants.A total of 23 participants (13 claudicants and 10 controls) took part in the study. Muscle-tendon dimensions and architecture, tendon properties, activation patterns and muscle strength, power and quality (specific tension) were assessed be integrating ultrasound imaging, electromyography and dynamometry. Stair gait biomechanics were analysed using 3D motion capture as indicators of whole body physical function. Within the claudicant cohort, disease severity was determined using the ankle brachial pressure index and walking performance assessed by a modified six-minute walk test. Average post-exercise ankle brachial pressure index of the claudicating-limbs were 0.55±0.21 with initial (onset of claudication pain) and absolute (maximal claudication pain) walking distances of 105±45m and 265±136m, respectively.The first study investigated the relationships between the resting architecture of the gastrocnemii and functional properties of the Achilles tendon with disease severity and walking endurance. Worse disease severity was significantly associated with longer fascicle: tendon length ratios in both lateral (R=-.789, P=.001) and medial (R=-.828, P=<.001) gastrocnemius, and increased tendon hysteresis (R=-.740, P=.006). This suggests that the Achilles tendon has undergone deleterious changes and the muscle has adopted a structure designed to compensate for this. However, the concomitant associations with poorer walking endurance indicate this mechanism is not effective. Walking endurance could also be explained by lateral and medial gastrocnemius pennation angle, maximum tendon force, tendon hysteresis and disease severity (R2=~0.6). The direction of coefficients within these models suggests that improving tendon properties and increasing strength, but without increasing pennation angle, would be beneficial for walking endurance. Thus, eccentric resistance training may be an effective exercise intervention.The second study investigated relationships between static and dynamic muscle quality with disease severity and walking endurance. The power-producing capabilities of claudicants’ plantarflexors (both the claudicating/painful limb and asymptomatic limb) were impaired compared to healthy controls, particularly at high contraction velocities (24% difference at 180°/s). This could be explained by some reduction in gastrocnemii muscle quality and a greater reliance on the prominently type I fibred soleus muscle. As reduced dynamic capability of the plantarflexor muscles was associated with disease severity (R=.541, P=.037) and walking endurance (R=.689, P=.006), high velocity resistance training of the plantarflexor muscles appears important to maintain functional performance.The third and fourth studies investigated the functionally challenging daily tasks of stair ascent and stair descent, respectively. During stair ascent, plantarflexor moments were similar in claudicants compared to healthy controls, indicating the muscle could meet the strength demands of this task. We also observed that ankle angular velocity at the instant of peak moment, peak ankle power generation, as well as propulsive and vertical forces, were all reduced during forward continuance in the claudicating-limb group. It seems that claudicants possess adequate levels of strength when moving more slowly but are unable to remain strong when moving more quickly, therefore it could be suggested that the slower walking speed is a means to allow claudicants to operate within safer limits relative to their maximal strength capacity. This provides further evidence, in a functional context, of the velocity-dependent limitations of the plantarflexors detected in study two. During stair descent we hypothesised that the task demands would be redistributed away from the affected plantarflexors towards the muscles surrounding the hips and knees. Instead, the claudicants placed a greater reliance on the plantarflexors compared to healthy controls (40% vs 28% of plantarflexor contribution to peak support moment). Additionally, a unique hip extensor strategy was exposed during weight acceptance that was adopted by 73% of the claudicating-limb group, which was also associated with increased disease severity. However this was not a mechanism to reduce the functional demands on the plantarflexors but rather to reduce demands on the knee musculature. These data indicate the claudicants were relying heavily on the functionally limited plantarflexors to absorb the falling body mass during weight acceptance in stair descent, which may pose an increased risk of falling.This thesis has identified important changes in the structure and quality of the gastrocnemii muscles and the properties and function of the Achilles tendon, that appear to influence whole body function during demanding and risky physical activities (stair negotiation) that necessitate alternate strategies. Taken as a whole, it is clear that high-velocity and eccentric resistance training would likely improve the musculoskeletal characteristics of claudicants, increase walking endurance and facilitate safe stair negotiation

Paper 1 - An investigation into transfer provision for children and young people with Autistic Spectrum Disorders.Paper 2 - The effects of school transfer for children and young people with Autistic Spectrum Disorders, focussing on positive and negative emotions reported by parents, schools and pupils

All Doctoral Theses For DEdPsych are presented as 2 linked research papersPaper 1 - Abstract This study represents the wider perspective of a 2-stage study about school transfers, for children with Autistic Spectrum Disorders. The study used a mixed methodology to investigate the experiences of children moving schools, as reported by parents and schools. Pre-move general satisfaction and post-move success ratings were high. Transfer arrangements varied greatly. Many respondents despite being positive overall about the move reported difficulties and frustrations for themselves and the children making the move. Communication between all stakeholders was seen to be a main factor in improving transfers, with an emphasis on the Teaching Assistant role and a whole school ethos towards ASD. Although strategies and guidance are widely available to improve transfer for children, not all pupils with ASDs and their parents, had access to the same level of enhanced transfer arrangements within the county. Paper 2 - Abstract This paper represents the more focussed perspective of a 2- stage study about school transfers, for children with Autistic Spectrum Disorders, in mainstream education. The study used a mixed methodology to investigate the experiences of children moving schools, as reported by parents and schools, with all participants, and via child interviews with a smaller sample. School transfer (as part of a 2- or 3-tier education system) was identified as a time which can be especially challenging for children with ASDs in mainstream schools. Looking at the emotional effects of transfer, the study found parents and schools reported high levels of increased anxiety among transferring children with ASDs. Qualitative analysis identified a wide variety of triggers to anxiety, and strategies to reduce anxiety that are being used in school and at home. Positive emotions expressed about the move were also explored. This anxiety reduced post-move for some of the children, but was maintained for some. Parents perceived higher levels of anxiety in their children than schools did throughout the transfer period, despite many rating the move as successful overall. The experience of a school move was found to be a time parents, as well as children, need the information and reassurance of a well-planned transfer, with appropriate strategies in place for their child and effective, open communication between home and schools to reduce the negative emotions that can surround change for children with ASDs, and celebrate the positive

The less acceptable face of capitalism: a study of British documentary during the rise of Thatcherism

This thesis is a study of the oppositional documentary practices produced by the Left in Britain during the rise of the New Right (c1968-1997). By situating the issue of class at the centre of my study, I seek to challenge poststructuralist histories of this moment which, I suggest, inadvertently hastened the triumph of Thatcherism by foreclosing the production of, or the devotion of critical attention to, representations of class. One project forms the kernel of this inquiry. It is Exit Photography Group’s photobook Survival Programmes: In Britain’s Inner Cities (Milton Keynes: The Open University Press, 1982): a study in words and images of the those whom Exit designate ‘the less acceptable face of capitalism’. This thesis is a careful and sustained analysis of Survival Programmes and a select series of interrelated documentary projects, both photographic and filmic, with which I place the photobook in conversation. Through the prism of Exit’s project, I explore representations of class and how those representations intersect with questions of race and gender, as well as with concerns about the changing usages of, and connotations attached to, public and private space. My approach is informed by the contemporaneous writings of the cultural studies and media theorist Stuart Hall. His work provides a lens through which I interrogate how oppositional image makers have mobilised the camera as a prism through which to scrutinise Thatcherism, as well as the mass media institutions through which that ideology has been creatively mediated and mobilised. I ask if we can write social histories of documentary after 1979 without reverting to the duality between the naive celebration of so-called “community photography” on the one hand and, on the other, deterministic accounts of the inevitable critical and political failure of the documentary modality

Graduate Student Perceptions of the Use of Online Course Tools to Support Engagement

Graduate students in six online courses were asked to complete a questionnaire related to dimensions of engagement including participation and interaction, performance, studying, and relevance of material. Students were asked to indicate the importance of various online course features (e.g., online discussions) in enhancing their engagement in each dimension using a Likert scale. Twenty-six (29%) students completed the questionnaire. Students rated most course management system features as extremely important or very important. When the ratings for the four engagement areas were grouped by course site feature, the feature with the highest mean rating was “instructor feedback on assignments/assessments.” The feature with the lowest mean rating was “online chats with other students.” While the practices of the instructor in the courses studied may have influenced the students’ perceptions, it is clear that students especially value contact with the instructor

Increasing College-Going Rate, Parent Involvement, and Community Participation in Rural Communities

This study examined the perceptions of leaders of grant-supported projects aimed at increasing the college-going rate of high school students in rural Appalachian counties in Mississippi to determine which factors they felt most influenced the college-going rate, parental participation in school activities, and community participation. Analysis of the leaders’ responses to questions related to these items showed that college visits and ACT preparation workshops were perceived as having the greatest impact on increasing the college-going rate at the schools. No one factor was perceived as having the least impact on increasing the college-going rate at the schools. Factors influencing parental and community participation included events and workshops for parents, especially those which involved community members as mentors. Acknowledgement: This research was supported by Appalachian Regional Commission Grant MS-16115