Bimetallic copper-aluminium tube by severe plastic deformation

A new process of joining tubes from different materials to a bimetallic tube based on a combination of large shear and high hydrostatic pressure is proposed. It results in improved mechanical locking of surface asperities, along with enhanced diffusivity owing to the ultrafine-grained microstructure produced. This is augmented by a temperature increase due to heat release associated with mechanical work. Electron microscopy characterization of the interface and the adjacent regions supports the hypothesis of enhanced interdiffusion.

A descriptive comparison of approaches to paediatric tube weaning across five countries

PURPOSE: Many children are requiring tube weaning intervention as a result of increased survival rates of high risk infants and the temporary use of feeding tubes. This study aimed to describe service delivery models and treatment approaches in a variety of paediatric feeding/tube weaning programs. METHOD: A questionnaire on tube weaning was formulated based on a literature review. Purposive maximum variation sampling was used to include feeding/ weaning programs operating in a variety of settings and countries. Eight feeding teams in Australia, Europe and the USA agreed to participate and completed the questionnaire. RESULT: All teams employed sensori-motor interventions, with the majority also offering psychological interventions. Six of eight teams utilised hunger induction during the initiation of tube weaning, and in many cases this preceded eating skill development or controlled sensory modulation. CONCLUSION: A multi-model tube weaning approach is commonly adopted by many centres worldwide. In many cases, psychological theory and theoretical orientation is fundamental to tube weaning practice. Further investigation regarding the efficacy and effectiveness of weaning interventions is recommended to ensure clinical practice is based on sound evidence. This may present as a challenge given many interventions occur concomitantly and the psychotherapeutic experience is difficult to evaluate.

Finite element modeling of tube deformation during cold pilgering

A three-dimensional finite element model of cold pilgering of stainless steel tubes is developed in this paper. The objective is to use the model to increase the understanding of forces and deformations in the process. The focus is on the influence of vertical displacements of the roll stand and axial displacements of the mandrel and tube. Therefore, the rigid tools and the tube are supported with elastic springs. Additionally, the influences of friction coefficients in the tube/mandrel and tube/roll interfaces are examined. A sensitivity study is performed to investigate the influences of these parameters on the strain path and the roll separation force. The results show the importance of accounting for the displacements of the tube and rigid tools on the roll separation force and the accumulative plastic strain.

"It's a tube up your bottom; it makes people nervous": the experience of anxiety in initial colonoscopy patients.

This study aimed to prospectively consider the effect of colonoscopy on patients' experiences of anxiety at 4 time points related to an initial colonoscopy, using a qualitative approach. The study involved a sample of 13 patients undergoing an initial colonoscopy at a public hospital and followed for 12 months. Four exploratory interviews were conducted with each participant: before the procedure, 1 week, 2 weeks, and 12 months after the procedure. Thematic analysis was conducted to summarize patients' responses. In these participants, colonoscopy was associated with stigma. The discussion of the procedure was perceived as stressful and embarrassing and led to anxiety. Irrational expectations regarding the procedure were also contributing to anxiety, as was a doctor-patient relationship based on unequal powers and lack of control. Before the procedure, fear of a serious diagnosis contributed to anxiety; however, postprocedure, an unclear or functional diagnosis also appeared to increase anxiety. Anticipating the preparation for the procedure was also reported as an important factor in preprocedure anxiety. A shift toward a biopsychosocial approach to healthcare, such as providing patients with a greater sense of control by participating in decision making, should be recommended as it may reduce anxiety.