The wall shear stress produced by the normal impingement of a jet on a flat surface

A method for the theoretical determination of the wall shear stress under impinging jets of various congurations is presented. Axisymmetric and two-dimensional incompressible jets of a wide range of Reynolds numbers and jet heights are considered. Theoretical predictions from this approach are compared with available wall shear stress measurements. These data are critically evaluated based on the method of measurement and its applicability to the boundary layer under consideration. It was found that impingement-region wall shear stress measurements using the electrochemical method in submerged impinging liquid jets provide the greatest accuracy of any indirect method. A unique wall shear stress measurement technique, based on observing the removal of monosized spheres from well-characterized surfaces, was used to conrm the impinging jet analysis presented for gas jets. The technique was also used to determine an empirical relation describing the rise in wall shear stress due to compressibility eects in impinging high-velocity jets

A thematic analysis of messages posted by moderators within health-related asynchronous online support forums

Objective: To identify and describe the activities performed by online support community moderators. Methods: A total of 790 messages were downloaded for analysis. Messages were written by 59 moderators from 6 forums that represent a diverse range of conditions (arthritis, complex regional pain syndrome, Crohn’s disease, depression, diabetes and Huntington’s disease). Results:Thematic analysis revealed four themes: supportive tasks supportive tasks involve providing help to members, moderators sharing experiences shows how they use forums to fulfil their own personal support needs, making announcements about new discoveries and upcoming events, and administrative tasks such as enforcing rules and deleting spam. Conclusion: These results are consistent with the helper-therapy principle and provide a new insight into the diverse and varied range of activities carried out by moderators. Practice implications: Moderators perform many roles, including using forums for their own support needs

Genetic testing for Huntington’s disease: A thematic analysis of online support community messages

Huntington’s disease is a fatal late-onset genetic illness that causes motor, cognitive and psychiatric disorders. Individuals considering genetic testing may benefit from online social support. This study investigates how genetic testing is discussed within health forums. 337 messages written by 58 individuals were analysed using deductive thematic analysis. Discussions examined three themes: deciding to be tested (enquiring about symptoms, starting a new family), preparing for the test (information seeking, attending appointments), and receiving the results (positive results, negative results). Forums can reduce the uncertainty of ambiguous symptoms, and provide ongoing personalized support before, during and after a genetic test

Online social support for complex regional pain syndrome

Individuals living with Complex Regional Pain Syndrome (CRPS) often experience difficulties taking part in social and recreational activities, which can leave them with a greatly reduced social network and limited opportunities for obtaining social support. Online support communities may provide individuals with an alternative way of obtaining social support, but few studies have examined these communities in the context of CRPS. Furthermore, most online support community research has focussed on established communities, and little is known about how new communities become established. This thesis examines a bespoke CRPS online support community with two broad aims: to examine the development of online support processes in relation to the launch of a new online support community, and to investigate the provision of social support for CRPS within an online support community. The dataset comprised 221 messages posted by 23 participants. Study 1 used the full dataset to examine engagement with the online support community, focussing on the number of individuals who used the forum (membership growth), how they used it (header analysis) and how they introduced themselves (introductory messages). Study 2 used the full dataset to investigate how support processes became established, the support content of messages, and how this contributed to the CRPS ‘four pillars of intervention’. Study 3 used four longitudinal case studies from the dataset to conduct a linguistic analysis of messages, focussing on support providing behaviour and the number of replies received. The results indicate that support processes start almost immediately when a new online support community is launched, and membership growth is closely linked to promotional strategies. Online support may play an important role in CRPS self-management by contributing to the ‘four pillars of intervention’, and there is a possibility that diffusion of responsibility may occur in forums. The longitudinal case study approach may produce important new insights and suggests that the use of health words is unrelated to the number of replies received, the use of self and other-oriented messages may be linked to health status and support providing activities, and that the ratio of positive-to-negative words could potentially be used to identify individuals who might benefit from additional support

The Effective Use of Educational Television

It was the purpose of this study to (1) establish a need for developing utilization procedures for educational television, (2) determine materials needed for effective use, (3) point out ways to prepare the classroom for most effective reception, (4) show how to orient students, (5) suggest viewing procedures, (6) cite the need for follow-up and possible follow-up techniques, and (7) indicate possible methods of evaluation for both program and students

Towards decentralized biogas generation: building community scale biogas reactors

This paper describes effort on the newly funded British Council project “Community Scale, decentralised Anaerobic Digestion for energy and resource recovery”. The aim of the project is to establish a network of small, community scale digesters both in Thailand and UK, for decentralised biogas generation from locally available wastes. We are especially focusing on food waste. The pilot digesters are paired with instruments for remote autonomous monitoring of biogas quality and conditions within the reactor (pressure, humidity). The data from networked reactors are collected on a single web portal, enabling remote monitoring. This reduces the need for trained personnel to be present at all times at each site. Reactor design is also described and the potential benefits and challenges are discussed

Avian diversity of rice fields in Southeast Asia

The thesis investigated avian diversity within rice fields at three locations in the Philippines. From February 2012 until April 2014, avian community structure was recorded to determine the effect that different farming techniques have upon frequency and abundance within the habitat. Investigations were conducted to challenge the common misconception that all birds are a threat to crop yield, with detailed research into the life-cycle and diet of the Eurasian tree sparrow (Passer montanus). Twenty-seven continuous months of bird surveys were conducted to record annual, and temporal, changes in frequency and diversity. A total of 130 species were recorded, and explanations for abundance patterns discussed. Species biological richness scores indicated that time of year and field stage are important factors affecting diversity within rice fields. To investigate the effect different farming techniques have upon avian diversity, two largescale crop manipulations were investigated; fields under a water management technique (Alternate Wetting and Drying) and areas of accelerated rice production. Both investigations indicated that avian frequency and abundance were higher within manipulated fields when compared to control sites. Differences in community structure are discussed identifying a change under manipulated conditions. Artificial nest boxes were used to record breeding season and productivity, with biometric measurements, for the Eurasian tree sparrow sub-species‘saturatus’, which produced more eggs but successfully fledged fewer young, over a longer breeding period. A significant difference in wing formulae between sexes indicates a difference in life-style strategies. To determine diet, stable isotopic analysis of claws measured ratios of δ15N. Differences in δ15N were compared to a control group fed on a ‘pure’ diet. Results indicated a mixed diet when given free choice, but could not be identified within the current data set. Management strategies to reduce potential yield loss to birds, along with considerations for future work, are discussed

Industrial scale anaerobic digestion of brewery effluent

Unilever AD facilities process brewery effluent using EGSB. Here, we report operational experiences over the period of three years. The process performance and stability is closely monitored by a range of parameters, including COD, pH, and suspended solids. Ripley’s ratio and volatile fatty acids, are the most successful to control. The feed COD concentration averages 15000 mg/l and is reduced to 120 mg/l in the effluent (99.2% COD reduction). Suspended solids concentrations are reduced from 2400 mg/l in the effluent to 55 mg/l. Biogas is being produced at an average of 80 m3/h, with 70±9% methane content. We pay special attention to the issues of gas/liquid separation