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Solar energy has the potential to supply more than enough energy to meet humanity’s energy demands. Here, a method for thermochemical solar energy storage through fuel production is presented. A porous non-stoichiometric oxide, ceria, undergoes partial thermal reduction and oxidation with concentrated solar energy as a heat source, and water as an oxidant. The resulting yields for hydrogen fuel and oxygen are produced in two discrete steps, while the starting material maintains its original phase.Ordered porosity has been shown superior to random porosity for thermochemical fuel production applications, but stability limits for these structures are currently undefined. Ceria-based inverse opals are currently being investigated to assess the architectural influence on thermochemical hydrogen production. Low tortuosity and continuous interconnected pore network allow for facile gas transport and improved reaction kinetics. Ceria-based ordered materials have recently been shown to increase maximum hydrogen production over non-ordered porous ceria. Thermal stability of ordered porosity was quantified using quantitative image analysis. Fourier analysis was applied to SEM images of the material. The algorithm results in an order parameter gamma that describes the degree of long range order maintained by these structures, where γ>4 signifies ordered porosity. According to this metric, a minimum zirconium content of 20 atomic percent (at%) is necessary for these architectures to survive aggressive annealing up to 1000˚C. Zirconium substituted ceria (ZSC) with Zr loadings in excess of 20at% developed undesired tetragonal phases. Through gamma, we were able to find a balance between the benefit of zirconium additions on structural stability and its negative impact on phase. This work demonstrates the stability of seemingly delicate architectures, and the operational limit for ceria based inverse opals to be 1000˚C for 1µm pore size. Inverse opals having sub-micron pores did not sustain ordered structures after heating, and those larger than 1µm had reinforced structural stability. Furthermore, this analysis was applied to materials which underwent isothermal hydrogen/water redox cycles. ZDC20 inverse opals having 300, 650 and 1000nm pore sizes maintained ordered porosity at 800˚C, indicating a novel opportunity for use at higher temperatures.The mechanism of inverse opal degradation was investigated. Both in situ and ex situ electron microscopy studies were performed on inverse opals subjected to high temperatures. Coarsening by surface diffusion was found to be the dominant grain growth mechanism. The inverse opal grain growth mechanism was found to deviate from that of porous materials due to the high porosity and an upper limit to grain size caused by structural confinement. Furthermore, in situ experiments enabled correlation of nano-scale grain growth to micro-scale feature changes, resulting in an empirical relationship.Lastly, this dissertation presents an investigation of the effect of ordered porosity on hydrogen production rate and quantity. These results differ from those presented in literature, and an opportunity for further investigation is proposed.

Recurrent and locally advanced colorectal cancers frequently require en bloc resection of involved organs to achieve negative margins. The aim of this review is to evaluate the most current literature related to the surgical management of locally advanced and recurrent colorectal cancer. A literature review was performed on the electronic databases MEDLINE from PubMed, EMBASE and the Cochrane library for publications in the English language from January 1993 to July 2013. The MeSH search terms ‘locally advanced colorectal cancer’, ‘recurrent colorectal cancer’ and ‘surgical management’ were used. A total of 1,470 patients with recurrent or locally advanced primary colorectal cancer were included in 22 studies. Surgical removal of the tumour with negative margins (R0) offers the best prognosis in term of survival with a 5-year survival of up to 70 %. MVR is needed in approximately 10 % with the most commonly involved organ being the bladder. The mean post-operative morbidity is 40 %, mainly relating to superficial surgical site infection, pelvic collections and delayed wound healing. Most patients will undergo radiotherapy and/or chemotherapy pre- or post-operatively. The mean 5-year overall survival for R0 resection is 50 % for recurrent and locally advanced primary tumours while survival following R1 or R2 is 12 and

The incidence of locally advanced prostate cancer has decreased in the last few decades since the introduction of screening programmes. Despite earlier detection and treatment, there is still a proportion of late presentation and/or recurrences (around 10 %) of locally advanced prostate cancer. Additionally, sporadic reports of synchronous pelvic neoplasms have been published with various treatment strategies to optimize patient survival. Pelvic exenteration is a technically demanding surgical procedure that is performed for locally advanced, recurrent or synchronous pelvic malignancies. The role of pelvic exenteration in locally advanced prostate cancer has been controversial, as there is a lack of strong statistical evidence to support its role. Despite this, studies have outlined benefits of this procedure, especially in the presence of synchronous pelvic cancers or for palliative indications. Despite advances in surgical care and techniques, pelvic exenteration remains a high-risk procedure with troublesome complications. However, with better patient selection, multi-disciplinary team (tumour board) involvement and surgery being performed in specialist high volumes centres, rates of morbidity and mortality have substantially reduced.

Urea transporters (UTs) encoded by the Slc14a1 (UT-B) and Slc14a2 (UT-A) genes facilitate the movement of urea across plasma membranes. Urea flux into the gastrointestinal tract enhances the growth...

Rectal carcinoids are increasing in incidence worldwide. Frequently thought of as a relatively benign condition, there are limited data regarding optimal treatment strategies for both localized and more advanced disease. The aim of this study was to summarize published experiences with rectal carcinoids and to present the most current data.Following PRISMA guidelines, an electronic literature search performed of PubMed, Medline, Embase, and the Cochrane Library using the terms "rectum" or "rectal" AND "carcinoid" over a 20-year study period from January 1993 to May 2013. Non-English-language studies, animal studies, and studies of fewer than 100 patients were excluded. Study end points included demographic information, tumor features, intervention and outcomes. All included articles were quality assessed.Using the search parameters and exclusions as outlined above, a total of 14 articles were identified for detailed analysis. The quality of articles was low/moderate for all included scoring 9 to 17 of 27. The articles included 4,575 patients diagnosed with a rectal carcinoid. Approximately 80% of tumors were10 mm, 15% 11-20 mm, and 5%20 mm. Eight percent of patients presented with regional lymph node metastases, and 4% presented with distant metastases. Tumor size10 mm, and muscular and lymphovascular invasion are independently associated with an increased risk of metastases. The 5-year survival was 93% in patients presenting with localized disease and 86% overall.Small tumors up to 10 mm without any adverse features can be treated with endoscopic or local excision. The treatment of carcinoids between 10 and 20 mm is still contentious, but those up to 16 mm without adverse feature are suitable for local/endoscopic excision followed by careful histopathological assessment. Those20 mm or with adverse features require radical surgery with mesorectal clearance in suitable patients.

• 1 University of Auckland, School of Psychology, New Zealand Background: Long-term potentiation (LTP) is a form of synaptic plasticity involved in learning and memory. Abnormal levels of LTP have been suggested to contribute to symptoms in a number of disorders, and here we examined the extent to which LTP may be affected in autism spectrum disorders (ASD). While animal models of ASD have suggested LTP may be atypical, the results have been inconsistent in terms of the direction of abnormality. Methods: An EEG paradigm for non-invasively eliciting LTP in humans was applied to a group of adults with ASD and matched neurotypical (NT) controls. This paradigm uses high frequency visual stimulation as the LTP inducing stimulus, and the increase in amplitude of the visually-elicited N1b component of the visual evoked potential (VEP) is taken as the index of LTP. Results: It was found that the ASD group had a significantly larger LTP effect relative to the neurotypical control group. Discussion: These results provide support for the “Intense World” theory, in which hyper-plasticity is thought to underlie cognitive symptoms in ASD. This non-invasive paradigm for eliciting LTP has potential to be applied in a clinical setting as a neural marker for ASD.