Vacuum moulding of a superplastic

The objective of this research is to develop a model for simulating the super-plastic forming process and for predicting the thickness distribution as well the minimum radius of curvature when the material has to fill a sharp corner. Other questions of interest are the deflection of the sheet as a function of pressure for a given mould opening, and the deflection as a function of mould diameter for a given pressure. Modeling based on shell theory is carried out for cylindrical, spherical and arbitrary-shape shells of uniform as well as non-uniform thick- nesses

Distribution of the spotted minnow (Galaxias maculatus (Jenyns, 1842)) (Teleostei: Galaxiidae) in Western Australia including range extensions and sympatric species

Galaxias maculatus was captured from a number of rivers outside its previously known range. In Western Australia, it was formerly only known from rivers and lakes between the Goodga River (Two People's Bay, 30 km east of Albany) and the Dailey River (50 km east of Esperance), with additional records from the Boat Harbour Lakes (Kent River). An intensive survey of the inland fishes in rivers and lakes along the south coast of Western Australia has extended its distribution east by 50 km (Thomas River), west by approximately 40 km (Walpole River) and north by 400 km (Harvey River). The Western Australian Museum also has a specimen from the Canning River, a further 100 km north. Field salinity tolerance of G maculatus was high, with fish found alive in 81 mScm 1 (-45 ppt). The freshwater piscifauna east of, and including, the Pallinup River is depauperate, with G. maculatusbeing the only freshwater species present. All sympatric teleosts are tolerant of salinity and, with the exception of the introduced Gambusia holbrooki, are estuarine, including Pseudogobius olorum, Leptatherina wallacei and Acanthopagrus butcheri

The genomic bases of morphological divergence and reproductive isolation driven by ecological speciation in Senecio(Asteraceae)

Ecological speciation, driven by adaptation to contrasting environments, provides an attractive opportunity to study the formation of distinct species, and the role of selection and genomic divergence in this process. Here, we focus on a particularly clear-cut case of ecological speciation to reveal the genomic bases of reproductive isolation and morphological differences between closely related Senecio species, whose recent divergence within the last ~200 000 years was likely driven by the uplift of Mt. Etna (Sicily). These species form a hybrid zone, yet remain morphologically and ecologically distinct, despite active gene exchange. Here, we report a high-density genetic map of the Senecio genome and map hybrid breakdown to one large and several small quantitative trait loci (QTL). Loci under diversifying selection cluster in three 5 cM regions which are characterized by a significant increase in relative (FST), but not absolute (dXY), interspecific differentiation. They also correspond to some of the regions of greatest marker density, possibly corresponding to ‘cold-spots’ of recombination, such as centromeres or chromosomal inversions. Morphological QTL for leaf and floral traits overlap these clusters. We also detected three genomic regions with significant transmission ratio distortion (TRD), possibly indicating accumulation of intrinsic genetic incompatibilities between these recently diverged species. One of the TRD regions overlapped with a cluster of high species differentiation, and another overlaps the large QTL for hybrid breakdown, indicating that divergence of these species may have occurred due to a complex interplay of ecological divergence and accumulation of intrinsic genetic incompatibilities

Ileus Management International (IMAGINE): protocol for a multicentre, observational study of ileus after colorectal surgery

AIM: The management of postoperative ileus following colorectal surgery remains controversial. It is the commonest complication after elective colorectal resection and is associated with an increased incidence of postoperative adverse events. The prevention and management of postoperative ileus remains unstandardized. This study aims to describe an international profile of gastrointestinal recovery after colorectal surgery and will assess the role of non-steroidal anti-inflammatory drugs, when used as postoperative analgesia, in expediting the return of gastrointestinal function. METHODS: A multicentre, student- and trainee-led, prospective cohort study will be conducted across both Europe and Australasia. Adult patients undergoing elective colorectal resection during 2-week data collection periods between January and April 2018 will be included. A site-specific questionnaire will capture compliance to Enhanced Recovery after Surgery components at participating centres. The primary outcome is time to gastrointestinal recovery, measured using a composite outcome of bowel function and oral tolerance. The impact of non-steroidal anti-inflammatory drugs on gastrointestinal recovery will be evaluated along with safety data with respect to anastomotic leak, acute kidney injury and complications within 30 days of surgery. DISCUSSION: This protocol describes the methodology of an international, observational assessment of gastrointestinal recovery after colorectal surgery. It discusses key challenges and describes how the results will impact on future investigation. The study will be conducted across a large student- and trainee-led collaborative network, with prospective quality assurance and data validation strategies

Isospectrality in Chaotic Billiards

We consider a modification of isospectral cavities whereby the classical dynamics changes from pseudointegrable to chaotic. We construct an example where we can prove that isospectrality is retained. We then demonstrate this explicitly in microwave resonators.Comment: 5 pages, 7 figure

Motion of spiral waves in the Complex Ginzburg-Landau equation

Solutions of the general cubic complex Ginzburg-Landau equation comprising multiple spiral waves are considered. For parameters close to the vortex limit, and for a system of spiral waves with well-separated centres, laws of motion of the centres are found which vary depending on the order of magnitude of the separation of the centres. In particular, the direction of the interaction changes from along the line of centres to perpendicular to the line of centres as the separation increases, with the strength of the interaction algebraic at small separations and exponentially small at large separations. The corresponding asymptotic wavenumber and frequency are determined. These depend on the positions of the centres of the spirals, and so evolve slowly as the spirals move