Scale size of magnetic turbulence in tokamaks probed with 30-MeV electrons

Measurements of synchrotron radiation emitted by 30-MeV runaway electrons in the TEXTOR-94 tokamak show that the runaway population decays after switching on neutral beam injection (NBI). The decay starts only with a significant delay, which decreases with increasing NBI heating power. This delay provides direct evidence of the energy dependence of runaway confinement, which is expected if magnetic modes govern the loss of runaways. Application of the theory by Mynick and Strachan [Phys. Fluids 24, 695 (1981)] yields estimates for the "mode width" (delta) of magnetic perturbations: delta<0.5 cm in Ohmic discharges, increasing to delta = 4.4 cm for 0. 6 MW NBI.     

Synthesis of [1,2,4]triazoloquinazolinones and imidazoquinazolinones

4-Quinazolinones have been cyclised to [1,2,4]triazoloquinazolinones and to imidazoquinazolinones. The direction of cyclisation has been proved by the unambiguous synthesis of their ethylation products.     

A substrate-free activity-based protein profiling screen for the discovery of selective PREPL inhibitors

Peptidases play vital roles in physiology through the biosynthesis, degradation, and regulation of peptides. Prolyl endopeptidase-like (PREPL) is a newly described member of the prolyl peptidase family, with significant homology to mammalian prolyl endopeptidase and the bacterial peptidase oligopeptidase B. The biochemistry and biology of PREPL are of fundamental interest due to this enzyme's homology to the biomedically important prolyl peptidases and its localization in the central nervous system. Furthermore, genetic studies of patients suffering from hypotonia-cystinuria syndrome (HCS) have revealed a deletion of a portion of the genome that includes the PREPL gene. HCS symptoms thought to be caused by lack of PREPL include neuromuscular and mild cognitive deficits. A number of complementary approaches, ranging from biochemistry to genetics, will be required to understand the biochemical, cellular, physiological, and pathological mechanisms regulated by PREPL. We are particularly interested in investigating physiological substrates and pathways controlled by PREPL. Here, we use a fluorescence polarization activity-based protein profiling (fluopol-ABPP) assay to discover selective small-molecule inhibitors of PREPL. Fluopol-ABPP is a substrate-free approach that is ideally suited for studying serine hydrolases for which no substrates are known, such as PREPL. After screening over 300,000 compounds using fluopol-ABPP, we employed a number of secondary assays to confirm assay hits and characterize a group of 3-oxo-1-phenyl-2,3,5,6,7,8-hexahydroisoquinoline-4-carbonitrile and 1-alkyl-3-oxo-3,5,6,7-tetrahydro-2H-cyclopenta[c]pyridine-4-carbonitrile PREPL inhibitors that are able to block PREPL activity in cells. Moreover, when administered to mice, 1-isobutyl-3-oxo-3,5,6,7-tetrahydro-2H-cyclopenta[c]pyridine-4-carbonitrile distributes to the brain, indicating that it may be useful for in vivo studies. The application of fluopol-ABPP has led to the first reported PREPL inhibitors, and these inhibitors will be of great value in studying the biochemistry of PREPL and in eventually understanding the link between PREPL and HCS.     

DSC investigations on condensation polymers—I. Analysis of the curing process

Curing reactions in thermosetting resins and resin-composite systems have been examined using differential scanning calorimetry. In particular, phenol-formaldehyde and melamine-formaldehyde systems have been investigated using small pressure-sealed capsules. Curing exotherms obtained from a single temperature scan have been analysed to give reaction kinetic parameters associated with the overall cure process. The reproducibility of the derived parameters, their variation with scan speed and the absolute values of reaction rate constants obtained, are discussed. The kinetic values are shown to be reasonably reliable when used to calculate extents of cure resulting from thermal curing cycles.     

Stock management after catastrophe the economics of hold or destroy

The problem of stock control after a dramatic decrease in demand is considered. This paper presents cash flow models of hold or destroy which are appropriate in such a situation. Certain assumptions are made which enable a simple model to be produced which takes into account the effects of inflation and incorporates cash-flow discounting. The results from this are then compared with some common heuristics and are found to have lower costs in every case.     

The use of alpha 2HS-glycoprotein and group specific component in typing forensic blood samples for discriminative and investigative purposes

Methods are described for phenotyping alpha 2HS-glycoprotein (A2HS) and group specific component (GC) in plasma and blood-stains. The methods have been developed to be sensitive, to provide unequivocal results and to give maximal information from minimal amounts of sample. In attempting to fulfill the last criterion, a new method is described for the simultaneous typing of alpha 2 HS-glycoprotein and group-specific component from serum or plasma samples. The use of these proteins in determining the racial origin of a blood sample is also discussed.     

Ionization energies and electronic structure of N3P3Cl6 as determined by UV photoelectron spectroscopy and the Xα scattered wave method

Ionization energies have been measured for N₃P₃Cl₆ by He I photoelectron spectroscopy and they are compared with values calculated with the overlapping-spheres version of the Xα scattered wave method; the average discrepancy is less than 0.4 eV. The wavefunctions and associated charge distributions are used for assessing models of ring π bonding, and comparisons are made with previous calculations for N₃P₃F₆ and N₄P₄F₈. The calculated charge distributions are related to trends in measured core electron binding energies, and have important implications for the interpretation of Faraday effect measurements on cyclic phosphazenes.