Psychometric evaluation of the early/late preferences scale.

This paper examines the psychometric quality of the Early/Late Preferences Scale (PS) relative to that of the Composite Morningness Scale (CS). Questionnaires were completed by 670 undergraduate students aged 16-37 years (mean 22.5), of whom 64% were female. Both scales displayed satisfactory inter-item correlations and similar total mean scores to those reported previously, although the CS had higher variability. Principal axis factor analysis produced single-factor solutions for both scales, although loadings for Items 7 and 9 on the PS were low. Internal consistencies for both scales were good (PS = 0.86, CS = 0.90) with only a small improvement achieved by deleting Items 7 and 9 from the PS. Test-retest reliability over 11 weeks was good for both scales (PS = 0.92, CS = 0.89). Differences between morning, evening and intermediate groups in self-rated alertness at different times of day, and significant correlations with other indices of morning-evening orientation, provided evidence of validity for both scales. These results indicate that PS is psychometrically comparable with CS. In view of its simpler format and lower cultural specificity, PS may be considered a preferable measure for most applications.     

Broadband coplanar waveguide-coplanar strip-fed spiral antenna

A novel broadband coaxial-coplanar waveguide-coplanar strip-fed spiral antenna is presented. The antenna has good radiation patterns and a return loss of better than 10 dB over a wide bandwidth from 0.4 to 3.6 GHz. A DC-3.7 GHz broadband balun was developed for the antenna feed     

Bio‐Derived Polymers for Sustainable Lithium‐Ion Batteries

Biologically derived organic molecules are a cost‐effective and environmentally benign alternative to the widely used metal‐based electrodes employed in current energy storage technologies. Here, the first bio‐derived pendant polymer cathode for lithium‐ion batteries is reported. The redox moiety is flavin and is derived from riboflavin (vitamin B₂). A semi‐synthetic methodology is used to prepare the pendant polymer, which is composed of a poly(norbornene) backbone and pendant flavin units. This semi‐synthetic approach reduces the number of chemical transformations required to form this new functional material. Lithium‐ion batteries incorporating this polymer have a 125 mAh g^?1 capacity and an ≈2.5 V operating potential. It is found that charge transport is greatly improved by forming hierarchical structures of the polymer with carbon black, and new insight into electrode degradation mechanisms is provided which should be applicable to polymer electrodes in general. This work provides a foundation for the use of bio‐derived pendant polymers in sustainable, high‐performance lithium‐ion batteries.     

Far infrared measurements of bulk and surface phonons in GaAs/AlAs superlattices

We have used far-infrared oblique-incidence reflection spectroscopy to study bulk phonon polaritons, and attenuated total reflection (ATR) spectroscopy to study surface phonon polaritons, in long-period GaAs/Al_xGa_1?xAs and short-period GaAs/AlAs superlattices. Results on the former are in good agreement with an effective-medium bulk-slab model of the dielectric tensor of the superlattice; results on the latter are analysed in terms of a model that contains dielectric-tensor contributions from the confined optic phonons.     

Novel bisquinoline antimalarials. Synthesis, antimalarial activity, and inhibition of haem polymerisation

We report the synthesis of two series of novel bisquinoline compounds that inhibit the growth of both chloroquine-sensitive and chloroquine-resistant strains of Plasmodium falciparum. To study the molecular basis of the action of these novel antimalarial drugs, we examined their ability to inhibit haem polymerisation in the presence and absence of parasite extracts. The level of antimalarial potency was correlated with the level of inhibition of haem polymerisation, suggesting that these bisquinolines exert their antimalarial activity by antagonising the sequestration of toxic haem moieties.     

Effect of radiation intensity on photo-oxidation of an air-blown bitumen

Xenon-arc irradiation was used to study the influence of a wide range of radiation intensity on the rate of photo-oxidation of a sample of air-blown bitumen as determined by infra-red spectroscopy. The xenon-arc was monitored to provide information on its rate of decay, and its range of intensity was compared with that of total solar radiation in Melbourne. Thermal (dark) oxidation rates were also determined at various temperatures. The information obtained is discussed in terms of the mechanism of photo-oxidation of bitumen and the relation to climatological data. Acceleration factors for oxidation of bitumen in the laboratory for prediction of durability were determined by applying the superposition principle to the data.     

HLA-DRB1 genes and disease severity in rheumatoid arthritis. The MIRA Trial Group. Minocycline in Rheumatoid Arthritis

OBJECTIVE: To examine the effect of alleles encoding the "shared"/"rheumatoid" epitope on rheumatoid arthritis (RA) disease severity in patients who participated in the minocycline in RA (MIRA) trial. METHODS: Of 205 patients with a week-48 visit, blood was available for typing of HLA-DRB1 and HLA-DQB1 in 174 (85%) and successfully completed in 169 (82%). Baseline erosions were used to assess disease severity and new erosions at the last visit served as a proxy for progression. RESULTS: At baseline, there was no association between the presence of erosive disease or rheumatoid factor status and the dose of rheumatoid epitope (homozygous, heterozygous, none) or the specific alleles identified. At the final visit, a gradient was observed for the 3 allelic subgroups (and their gene doses) in the occurrence of new erosions among the Caucasian placebo-treated, but not the minocycline-treated, patients. A treatment group/HLA-DR4 epitope interaction was demonstrated in multivariate analyses. Approximately two-thirds of African-American patients did not have the rheumatoid epitope. CONCLUSION: HLA-DRB1 oligotyping may be useful in predicting the progression of disease in some Caucasian patients. Our study corroborates the infrequency of the epitope among African-American patients with RA.     

Epoxidation catalysts derived from introduction of titanium centers onto the surface of mesoporous aluminophosphate: Comparisons with analogous catalysts based on mesoporous silica

Titanium/AlPO materials were prepared by grafting a titanium alkoxide (titanium isopropoxide) onto a mesoporous aluminophosphate. The structures of the surface-bound titanium species were investigated by UV–vis, FTIR, MAS NMR, and XANES/EXAFS spectroscopies. The titanium anchoring occurs by reaction between the alkoxide precursor and surface Al–OH and P–OH groups of the AlPO support. The titanium species exist in isolated tetrahedral coordination environments, and as oligomerized species. The catalysts prepared are selective and active for the liquid-phase epoxidation of cyclohexene in the presence of TBHP. The observed activities and selectivities were comparable with those obtained for similarly prepared titanium/SBA-15 samples of similar Ti content (but higher BET surface area).