The parthogenesis of ulcerative colitis: The role of autoimmunity and microvascular injury.

Aims: To investigate the roles of autoimmunity and microvascular injury in the pathogenesis of ulcerative colitis. Background: The aetiology of ulcerative colitis is unknown. A putative mucosal autoantigen, (UCAg), had been identified as tropomyosin, the presence of ANCA in ulcerative colitis suggested involvement of vascular factors; and disease demarcation suggested vascular anatomical distribution of disease. Methods: Using the monoclonal antibody 7E12H12, cellular localisation of the target antigen, UCAg, was studied. Comparative immunohistochemical studies were made of the staining patterns of 7E12H12 and anti-tropomyosin antibodies. The nature of the UCAg was examined further using SDS-PAGE and Western blotting. A novel dot-blot technique examined potential binding between tropomyosin and 7E12H12. In-vitro angiography examined the relation between vascular factors and the distribution of disease. The frequency of ANCA and the target antigen(s) was examined in patients with inflammatory bowel disease. Results: Immunohistochemistry demonstrated plasma membrane localisation of UCAg and revealed additional supranuclear staining. Comparative immunostaining experiments failed to show a similar localisation pattern for tropomyosin. There was no relation between UCAg expression and disease activity. SDS-PAGE, Western blotting and dot-blot experiments confirmed the presence of UCAg and tropomyosin in colon protein extracts, but no reactivity between 7E12H12 and tropomyosin. In-vitro angiography of resected ulcerative colitis colon specimens revealed a consistent relationship between the marginal artery of the colon and disease extent. ANCA were found in 57% of patients with ulcerative colitis. Novel antigenic targets for ANCA were identified: ANCA directed against bactericidal/permeability increasing protein were found in 27% of patients. Conclusions: UCAg is not tropomyosin, but the nature of this antigen remains to be determined. Novel target antigens for ANCA, present in vasculitis, have been identified in ulcerative colitis. The extent of disease appears to be determined by the anatomy of the marginal artery. These data suggest a microvascular pathogenesis for ulcerative colitis

Optical properties of high quality Cu2ZnSnSe4 thin films

Cu2ZnSnSe4 thin films, fabricated on bare or molybdenum coated glass substrates by magnetron sputtering and selenisation, were studied by a range of techniques. Photoluminescence spectra reveal an excitonic peak and two phonon replicas of a donor-acceptor pair (DAP) recombination. Its acceptor and donor ionisation energies are 27 and 7 meV, respectively. This demonstrates that high-quality Cu2ZnSnSe4 thin films can be fabricated. An experimental value for the longitudinal optical phonon energy of 28 meV was estimated. The band gap energy of 1.01 eV at room temperature was determined using optical absorption spectr

Artificial molecular quantum rings: Spin density functional theory calculations

The ground states of artificial molecules made of two vertically coupled quantum rings are studied within the spin density functional theory for systems containing up to 13 electrons. Quantum tunneling effects on the electronic structure of the coupled rings are analyzed. For small ring radius, our results recover those of coupled quantum dots. For intermediate and large ring radius, new phases are found showing the formation of new diatomic artificial ring molecules. Our results also show that the tunneling induced phase transitions in the coupled rings occur at much smaller tunneling energy as compared to those for coupled quantum dot systems.Comment: 10 pages, 6 figure

Optimisation of the bidding strategy for wind power trading

The optimal bidding strategy for trading electricity from a wind farm is not always clear. This paper outlines a method for predicting whether the market will be long or short and uses this information to select the best quantile regression for the current market conditions. Results from a simulation with a 2.5MW turbine produced a savings of over £2,000 compared to using only a P50 forecaster

Population-weighted degree-days: The global shift between heating and cooling

Anthropogenic greenhouse gas emissions are driving global increases in temperature. This rise will likely lead to an increase in demand for cooling in the coming years. However, increasing temperatures are not the main explanatory factor for why the world is moving towards more cooling. This paper compares population and area-weighted cooling and heating degree-days derived using ERA5-Land reanalysis temperature, to show that population growth in warmer parts of the world drives cooling demand globally. The analysis shows that mean global area-weighted heating degree-days have fallen 8.46 °C days/year, whereas population-weighted heating degree-days have fallen by 12.5 °C days/year. At the same time, mean global area-weighted cooling degree-days have risen by 3.0 °C days/year, while population-weighted cooling degree-days have risen at 6.0 °C days/year. By using sub-country analysis, this paper shows that population-weighted degree-days can substantially differ from area-weighted degree-days. Finally, the findings highlight that the choice of heating and cooling degree-day base temperature is the most important parameter in the variability of degree-days and will need to be understood better in order to accurately account for future heating and cooling energy demand

Nondestructive Evaluation of Graphite/Epoxy Composite Damage

Ultrasonic and acoustic emission techniques were used to monitor and evaluate material damage in a graphite/epoxy laminate containing a machined hole as an initial flaw and subjected to fully reversed spectrum fatigue loading at room temperature. It was found that the flaw growth progressed radially around the initial hole at a uniform rate during cycling at the lower stress levels. At the higher levels, material damage accelerated dramatically, progressing faster in the transverse direction toward the free edges. By close examination of the A-scan and RF spectrum photographs, it was determined that damage modes could be defined as to their extent and relative location within the specimen. These conclusions were supported by photographs of the failed specimen

Phylogeny of the Hawkmoth tribe Ambulycini: mitogenomes from museum specimens resolve major relationships

Ambulycini are a cosmopolitan tribe of the moth family Sphingidae, comprised of ten genera, three of which are found in tropical Asia, four in the Neotropics, one in Africa, one in the Middle East and one restricted to the islands of New Caledonia. Recent phylogenetic analyses of the tribe have yielded conflicting results, and some have suggested a close relationship of the monobasic New Caledonian genus Compsulyx Holloway, 1979 to the Neotropical ones, despite being found on opposite sides of the Pacific Ocean. Here we investigate relationships within the tribe using full mitochondrial genomes, mainly derived from dry-pinned museum collections material. Mitogenomic data were obtained for 19 species representing nine of the ten Ambulycini genera. Phylogenetic trees are in agreement with a tropical Asian origin for the tribe. Furthermore, results indicate that the Neotropical genus Adhemarius Oiticica Filho, 1939 is paraphyletic and support the notion that Orecta Rothschild & Jordan 1903 and Trogolegnum Rothschild & Jordan, 1903 may need to be synonymized. Finally, in our analysis the Neotropical genera do not collectively form a monophyletic group, due to a clade comprising the New Caledonian genus Compsulyx and the African genus Batocnema Rothschild & Jordan, 1903 being placed as sister to the Neotropical genus Protambulyx Rothschild & Jordan, 1903. This finding implies a complex biogeographic history and suggests the evolution of the tribe involved at least two long-distance dispersal events