Chris Preston

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or<lb>171<lb>algebra<lb>12, 25<lb>adapted to typed set<lb>150<lb>associated<lb>37, 43, 150, 152<lb>bottomed<lb>58<lb>category-based<lb>126<lb>containing a typed set<lb>37<lb>disjoint from a typed set<lb>46<lb>extension of<lb>46<lb>free<lb>37<lb>functionally free<lb>145, 147<lb>functional<lb>145, 147<lb>ground(More)
These notes present an approach to obtaining the basic properties of the natural numbers in terms of the properties of finite sets (which are introduced independently of the natural numbers). The role played by the usual recursion theorem is taken over by a construction which can be regarded as a recursion theorem for finite sets.
  • Chris Preston
  • Nursing standard (Royal College of Nursing (Great…
  • 1994
We have all either heard it or had it said to us. As she prepares to inject, Julie, the nurse, says: Don't worry, this won't hurt a bit'. Suitably reassured, John, the patient offers an arm and... ouch. Julie lied.
Analysis of Artemisia annua extracts by liquid chromatographic methods has traditionally been complicated by the presence of significant quantities of impurities. It has been observed that these impurities often remain as a solid residue after sample reconstitution, but the possibility of artemisinin remaining entrained within this waxy layer has not been(More)
OBJECTIVES Cleaning verification is a scientific and economic problem for the pharmaceutical industry. A large amount of potential manufacturing time is lost to the process of cleaning verification. This involves the analysis of residues on spoiled manufacturing equipment, with high-performance liquid chromatography (HPLC) being the predominantly employed(More)
The set-up we work with here consists of non-empty sets S and X, a mapping f : S × X → X and an element x0 ∈ X. The mapping f will also be regarded as a family of mappings {fs}s∈S, where fs : X → X is given by fs(x) = f(s, x) for all x ∈ X. A subset X ′ of X is said to be f -invariant if f(S ×X ) ⊂ X , i.e., if fs(X ) ⊂ X ′ for each s ∈ S, and the mapping f(More)