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51.
Broughton J 《Accident; analysis and prevention》2007,39(2):274-283
This paper examines the link between traffic offences and criminal offences in Great Britain statistically by linking offence data from two national sources: the Driving and Vehicle Licensing Agency (DVLA) and the Home Office. A stratified sample of over 52,000 drivers was selected from DVLA records and matched with the Home Office Offenders Index. The numbers of motoring and non-motoring offences committed by these drivers between 1999 and 2003 were compared at various levels of detail. The results demonstrate the strength of the relationship between the number of motoring and non-motoring offences committed. For example, men who committed between 4 and 8 non-motoring offences committed on average 21 times as many serious motoring offences as men who committed no non-motoring offences, and 3.9 times as many other motoring offences. The strongest relationship was found for the offence of driving while disqualified: on average, men who committed at least 9 non-motoring offences between 1999 and 2003 committed more than 100 times as many of these offences as men who committed no non-motoring offences. At the other extreme, the number of speeding offences was found to decrease with the number of non-motoring offences committed. 相似文献
52.
Kocer HB Cerkez I Worley SD Broughton RM Huang TS 《ACS applied materials & interfaces》2011,3(8):2845-2850
A new N-halamine copolymer has been prepared, characterized, and evaluated for antimicrobial efficacy, stability toward hydrolyses, and stability toward UVA degradation when covalently bound to cellulose fibers. A copolymer of 3-chloro-2-hydroxypropylmethacrylate and glycidyl methacrylate was coated onto cotton, and, after curing, was treated with an aqueous solution containing the potassium salt of 5,5-dimethylhydantoin to form a coating which became antimicrobial upon exposure to househod bleach (sodium hypochlorite). The coating inactivated S. aureus and E. coli O157:H7 within minutes of contact time and was quite stable toward washing and UVA photodegradation. 相似文献
53.
Kocer HB Cerkez I Worley SD Broughton RM Huang TS 《ACS applied materials & interfaces》2011,3(8):3189-3194
A series of copolymers containing units of a novel hydantoinylacrylamide and the sodium salt of 2-(acrylamido)-2-methylpropanesulfonic acid have been synthesized. The homopolymer of the hydantoinylacrylamide compound was insoluble in water, while the copolymers with the sulfonic acid sodium salt were water-dispersible/soluble, with the solution becoming completely transparent when the feed ratio for the copolymer contained 7 parts of the hydantoin moiety to 3 parts of the sodium sulfonate moiety. The polymers were added into a commercial water-based latex paint, and upon drying, the painted surfaces treated with the water-miscible copolymers were rendered antimicrobial following chlorination with dilute household bleach. The chlorinated homopolymer failed to provide an antimicrobial property for the paint because of its tendency to isolate into aggregates in the paint, while the completely miscible copolymers were capable of 6-log inactivation of Staphylococcus aureus and Escherichia coli O157:H7 within 5 min of contact time. 相似文献
54.
A new algorithm is presented which aims to solve problems from compressed sensing - under-determined problems where the solution vector is known a priori to be sparse. Upper bounds on the solution vector are found so that the problem can be reformulated as a box-constrained quadratic programme. A sparse solution is sought using a Barzilai-Borwein type projection algorithm. New insight into the choice of step length is provided through a study of the special structure of the underlying problem together with upper bounds on the step length. Numerical experiments are conducted and results given, comparing this algorithm with a number of other current algorithms. 相似文献
55.
Jian Lin Catherine Winkelman S. D. Worley R. M. Broughton J. F. Williams 《应用聚合物科学杂志》2001,81(4):943-947
The preparation of an antimicrobial nylon material and its properties are discussed. Biocidal cyclic N‐chloramine moieties were covalently bonded to Nylon 66. These moieties, which included hydantoins, oxazolidinones, and imidazolidinones, were stable during at least 3 months of dry storage, and their antimicrobial activities, once lost by reaction with reducing sodium thiosulfate, could be regenerated by exposure to free chlorine. Biocidal swatch tests showed that the nylon fabrics containing N‐chlorinated hydantoin functional groups provided a 7.2 log reduction of Staphylococcus aureus and a 7.1 log reduction of Escherichia coli at a contact time of only 10 min. Antimicrobial nylon should find a variety of important uses such as in clothing, carpets, sutures, brushes, and so forth. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 943–947, 2001 相似文献
56.
JQ Liu T Kurihara S Ichiyama M Miyagi S Tsunasawa H Kawasaki K Soda N Esaki 《Canadian Metallurgical Quarterly》1998,273(47):30897-30902
Fluoroacetate dehalogenase (EC 3.8.1.3) catalyzes the dehalogenation of fluoroacetate and other haloacetates. The amino acid sequence of fluoroacetate dehalogenase from Moraxella sp. B is similar to that of haloalkane dehalogenase (EC 3.8.1.5) from Xanthobacter autotrophicus GJ10 in the regions around Asp-105 and His-272, which correspond to the active site nucleophile Asp-124 and the base catalyst His-289 of the haloalkane dehalogenase, respectively (Krooshof, G. H., Kwant, E. M., Damborsky, J., Koca, J., and Janssen, D. B. (1997) Biochemistry 36, 9571-9580). After multiple turnovers of the fluoroacetate dehalogenase reaction in H218O, the enzyme was digested with trypsin, and the molecular masses of the peptide fragments formed were measured by ion-spray mass spectrometry. Two 18O atoms were shown to be incorporated into the octapeptide, Phe-99-Arg-106. Tandem mass spectrometric analysis of this peptide revealed that Asp-105 was labeled with two 18O atoms. These results indicate that Asp-105 acts as a nucleophile to attack the alpha-carbon of the substrate, leading to the formation of an ester intermediate, which is subsequently hydrolyzed by the nucleophilic attack of a water molecule on the carbonyl carbon atom. A His-272 --> Asn mutant (H272N) showed no activity with either fluoroacetate or chloroacetate. However, ion-spray mass spectrometry revealed that the H272N mutant enzyme was covalently alkylated with the substrate. The reaction of the H272N mutant enzyme with [14C]chloroacetate also showed the incorporation of radioactivity into the enzyme. These results suggest that His-272 probably acts as a base catalyst for the hydrolysis of the covalent ester intermediate. 相似文献
57.
58.
59.
ML Schmidt VM Lee M Forman TS Chiu JQ Trojanowski 《Canadian Metallurgical Quarterly》1997,151(1):69-80
Methionine metabolism and transmethylation are central to the metabolism and differentiation of all known cells. In enkaryotic organisms, methionine metabolism and transmethylation are of paramount importance in modification and regulation of proteins, lipids, and nucleic acids. The differential methylation of genes regulates their expression in the myriad of cells in eukaryotic organisms. Disruption and abnormalities in methionine metabolism and transmethylation seems to be associated with the major diseases of mankind, including cancer, heart disease, aging, obesity, and Parkinson's disease. In this review, we describe how aberrant and abnormal methionine metabolism and transmethylation are related to these major diseases. Most importantly, we review and hypothesize how the developing therapeutic recombination methioninase (rMETase) can be utilized to cure or prevent all of these diseases. 相似文献
60.
A Ozarowski JQ Wu SK Davis CY Wong MR Eftink AH Maki 《Canadian Metallurgical Quarterly》1998,37(25):8954-8964
Phosphorescence and optically detected magnetic resonance (ODMR) measurements are reported on the triplet states of the tryptophan analogues, 7-azatryptophan (7AW), 5-hydroxytryptophan (5HW), and 4-, 5-, and 6-fluorotryptophan (4FW, 5FW, 6FW), when incorporated at position 140 of wild-type Staphylococcal nuclease (7AW-nuclease, etc. ), positions 66 and 140 of its V66W mutant (7AW-V66W, etc.), and the deletion fragment of the latter, Delta 137-149 (7AW-V66W', etc.). These measurements point to the retention of protein structure at position 140 in each of the wild-type nuclease analogues. Substitution of the analogue at both tryptophan sites of V66W leads to structured sites with differentiated triplet-state properties for all analogues except 7AW-V66W, whose structure is destabilized. 5HW-V66W' is the only fragment that apparently lacks structure at position 66. All other V66W' analogues exhibit a structured environment at position 66 (4FW-V66W' was not studied), but in each case this site can be differentiated readily from the corresponding site in intact V66W. 7AW-V66W' is resolved by ODMR into two discrete structures with slightly differing zero field splittings (ZFS). Interaction of the protein with 5HW at position 66 of 5HW-V66W induces a 2-fold increase in the ZFS E parameter, which is reduced to its normal value upon formation of the fragment, 5HW-V66W'. Analogous effects occur for 5FW, but on a smaller scale. 相似文献