820 research outputs found
The Tuza–Vestergaard Theorem
No full textThe transversal number τ(H) of a hypergraph H is the minimum number of vertices that intersect every edge of H. A 6-uniform hypergraph has all edges of size 6. On 10 November 2000 Tuza and Vestergaard [Discuss. Math. Graph Theory, 22 (2002), pp. 199-210] conjectured that if H is a 3-regular 6-uniform hypergraph of order n, then τ(H) ≤ 1/4n. In this paper we prove this conjecture, which has become known as the Tuza-Vestergaard conjecture.</p
Cut-elimination, substitution and normalisation
No full textDate of Acceptance: 01/2015We present a proof (of the main parts of which there is a formal version, checked with the Isabelle proof assistant) that, for a G3-style calculus covering all of intuitionistic zero-order logic, with an associated term calculus, and with a particular strongly normalising and confluent system of cut-reduction rules, every reduction step has, as its natural deduction translation, a sequence of zero or more reduction steps (detour reductions, permutation reductions or simplifications). This complements and (we believe) clarifies earlier work by (e.g.) Zucker and Pottinger on a question raised in 1971 by Kreisel.Peer reviewe
Surfactant protein D in atopic dermatitis and psoriasis
No full textThe collectin surfactant protein-D (SP-D) shows antimicrobial and immuno-regulatory properties and has recently been detected in the basal layers of normal human skin. This molecule potentially plays an important role in inflammatory skin diseases and therefore SP-D content and location was examined using immunohistochemistry on skin biopsies from patients with the two major dermatologic diseases, psoriasis and atopic dermatitis. SP-D was located in the stratum basale of all biopsies with similar intense staining in both diseased and normal skin. Differences were detected in stratum spinosum where involved psoriatic skin showed intense staining through the entire region significantly different from uninvolved and normal skin. Lesional atopic skin showed moderate staining extending through the basal three-fourths of stratum spinosum. Using real time polymerase chain reaction analysis, no substantial up-regulation of SP-D mRNA was detected in lesional psoriatic skin, and a comparison of serum levels of SP-D between patients with atopic dermatitis or psoriasis and a group of age matched healthy controls did not show significant differences. In conclusion SP-D was significantly more abundant in the stratum spinosum of lesional psoriatic and atopic skin due to more cells producing the molecule rather than up-regulation of production in single cells of diseased skin. Further studies are needed to show if SP-D plays a role in the protection against skin infections or modulation of the inflammatory process in these common skin diseases
THE DEVELOPMENT OF A METHODOLOGY FOR THE COST JUSTIFICATION OF NEW MANUFACTURING INVESTMENTS
No full textThis work addresses the problems faced by small and medium manufacturing enterprises (SME\u27s) in cost justifying new investments in tools, techniques and technologies, and presents a methodology which significantly improves on current cost justification techniques. The methodology provides a structured approach which leads a company through a series of workshops, which assist a company in establishing the full company wide benefits and costs associated with new manufacturing investment. A model, in the form of a workbook and the specification for a prototype computer based tool, of the tasks necessary in cost justification is presented. The model is used to structure the decisions relating to possible investments. The research work described involved two distinct stages. The first stage included a fifteen month involvement in the Finjust project - a financial justification project sponsored by the DTI, in collaboration with Quintec Applied Systems, Mundy Johnson, Entrepreneurial Technologies and the University of Plymouth, where the author\u27s individual contribution was for the identification of the links between business needs and technologies and specifying the benefits of the investments. The author\u27s involvement in the project allowed the strategy to be tested in the collaborating companies. In the second stage, the major contribution of the research lies in the development of a new methodology, which whilst based on some of the principles of the Finjust project, incorporates many new ideas which significantly improve its value to SME\u27s. Through the use of this work SME\u27s are encouraged to improve ownership and commitment to the manufacturing solutions identified by fully involving relevant company personnel in the identification of business needs, the generation of solutions and the financial justification of proposed investments. This work also provides a mechanism to facilitate management development and training in financial justification by providing rationales for each activity, forms for the collection of data and tool kits to assist in the completion of specific tasks. The results of this work have provided the data necessary for the specification and building of an improved methodology in the form of a workbook
Museums Education - Opportunities and challenges in the collaboration between school and museum
No full text- …
