2,3,3 ',4 '-tetramethylbiphenyl

2,3,3',4'-Tetramethylbiphenyl, C<sub>16</sub>H<sub>18</sub>, was synthesized in a palladium-catalysed boronic acid cross-coupling reaction. In the solid state, these weakly interacting unsymmetrical molecules show an apparent dimerization of the ortho-dimethylphenyl groups, a packing motif that is seen in a significant number of other ortho-dimethylphenyl-containing compounds

Loggerhead turtle (Caretta caretta) nest predation at Cape Range National Park

Most of the existing sea turtle populations worldwide are in decline. In particular, loggerhead turtles (Caretta caretta) are listed as endangered and loggerhead nesting populations in Eastern Australia have declined by 86% since the 1970s. However, whilst Eastern Australian loggerhead populations have been extensively studied and monitored, not much is known about the Western Australian nesting population

Economic evaluation of a community based exercise programme to prevent falls

OBJECTIVE: To assess the incremental costs and cost effectiveness of implementing a home based muscle strengthening and balance retraining programme that reduced falls and injuries in older women. DESIGN: An economic evaluation carried out within a randomised controlled trial with two years of follow up. Participants were individually prescribed an exercise programme (exercise group, n=116) or received usual care and social visits (control group, n=117). SETTING: 17 general practices in Dunedin, New Zealand. PARTICIPANTS: Women aged 80 years and older living in the community and invited by their general practitioner to take part. MAIN OUTCOME MEASURES: Number of falls and injuries related to falls, costs of implementing the intervention, healthcare service costs resulting from falls and total healthcare service costs during the trial. Cost effectiveness was measured as the incremental cost of implementing the exercise programme per fall event prevented. MAIN RESULTS: 27% of total hospital costs during the trial were related to falls. However, there were no significant differences in health service costs between the two groups. Implementing the exercise programme for one and two years respectively cost $314 and$265 (1995 New Zealand dollars) per fall prevented, and $457 and$426 per fall resulting in a moderate or serious injury prevented. CONCLUSIONS: The costs resulting from falls make up a substantial proportion of the hospital costs for older people. Despite a reduction in falls as a result of this home exercise programme there was no significant reduction in healthcare costs. However, the results reported will provide information on the cost effectiveness of the programme for those making decisions on falls prevention strategies

Initial assessment of hot-melt extrusion for processing API with a wide range of physical properties to form consistent solid dispersion : HPMC-Affinisol paracetamol system

The aim of this work is to: (1) Determine the viable processing window of HPMC-Affinisol polymer to use in hot melt extrusion. (2) Use this polymer for oral formulations with Paracetamol over a wide range of physical grades and determine the effect of API particle size on the nature of the resulting formulated mixtures. (3) Assess if HME can be used to produce a consistent output with wide ranges in physical input API properties

Nanostructure and paramagnetic centres in diamond-like carbon: Effect of Ar dilution in PECVD process

Diamond-like carbon (DLC) films were deposited utilising plasma enhanced chemical vapour deposition (PECVD) with acetylene precursor, diluted with 0 – 45% argon. Electron paramagnetic resonance (EPR) measurements show the presence of one paramagnetic centre with no change in spin population over the range of film deposition conditions. However, the EPR linewidth decreases with increasing argon content of the precursor mix, suggesting an enhancement of motional narrowing due to an increase in electron delocalization, related to an increase in the sp2 cluster size. Atomic force microscopy (AFM) measurements indicate the surface of the DLC is formed of nanoscale asperities of material. With radii of tens of nanometres for films deposited with zero argon, the size of the features increases with the argon dilution of the acetylene. Energy dispersive x-ray analysis and electrical measurements further elucidate the changes in film structure

Risk-taking behaviour of Cape Peninsula high-school students. Part I. Introduction and methods

In this study, risk-taking behaviour of Cape Peninsula high-school students was investigated. Suicidal behaviour, cigarette smoking, alcohol consumption, drug use, road-related behaviour, violent behaviour and sexual behaviour were included. This article, the first in a series, describes the rationale and methodology of the project. Sixteen schools were selected so as to yield a representative sample of schools in the three major education departments in the Cape Peninsula (administered by the Department of Education and Training and the Houses of Assembly and Representatives). The final sample size was 7 340 school students. A self-administered questionnaire was completed in a normal school period. Estimates for each education department were weighted to produce an overall estimate. The results are presented by standard and home language(s), and gender. Limitations of the study include its cross-sectional nature; the possibility of under- and over-reporting; the exclusion of important groups of adolescents such as absentees and dropouts, and those attending specialised and private schools; and not being able to present the results separately for each education department

Conservation tillage increases in soil water storage, soil animal populations, grain yield, and response to fertiliser in the semi-arid subtropics

We compared 4 tillage practices (traditional, stubble mulch, reduced, no tillage) during 10 years under rainfed conditions on an alluvial soil in the semi-arid subtropics of central Queensland. In the final 4 years, responses to applied fertiliser nitrogen (N), sulfur (S), and zinc (Zn) were determined. We measured soil water storage, soil nitrate accumulation, grain yield (sorghum, wheat), grain protein content, and populations of soil macrofauna, with the aim of identifying soil-conserving practices that also produce high yields of high quality grain. Stubble mulch, reduced tillage, and no tillage all outyielded traditional tillage when soil fertility was adequate. With applied N, S, and Zn, the mean wheat yields from traditional, stubble mulch, reduced, and no tillage were 2.44, 3.32, 3.46, and 3.64 t/ha, respectively. The yield responses to tillage practices were due to increases in storage of soil water or efficiency of crop water use or both. Populations of soil macrofauna averaged (per m2) 19 (traditional tillage), 21 (stubble mulch), 33 (reduced tillage), and 44 (no tillage). The effect of the tillage practices on soil animal populations may be a factor contributing to the measured differences in soil water storage and water use efficiency. We conclude that conservation tillage practices can greatly increase grain yields, provided crop and fallow management practices are appropriate. Potential yield advantages are realised if crop establishment, crop nutrition; and control of weeds, bests, and diseases are adequate

Risk-taking behaviour of Cape Peninsula high-school students. Part IV. Alcohol use

The prevalence of a wide range of risk-taking behaviour among high-school students in the Cape Peninsula, South Africa, was investigated. In this article, the results for alcohol use are presented. Cluster sampling techniques produced a sample of 7 340 students from 16 schools in the three major education departments. A self-administered questionnaire was completed in a normal school period. Estimates for each education department were weighted to produce an overall estimate. Of the sample, 53,2% reported ever using alcohol; 26,2% had used it recently and 15,4% reported episodes of binge drinking in the previous 14 days. Drinking patterns varied according to school standard, home language, and gender. Males reported higher rates of alcohol use and for both genders rates increased with age. Overall, the prevalence of drinking was highest among adolescents whose home language was English. The proportion of Xhosa-speaking females who drank was very low.The prevalence of binge drinking in particular was identified as being of concern. The findings indicate a need for preventive action and further local research in this area

Risk-taking behaviour of Cape Peninsula high-school students. Part VII. Violent behaviour

The prevalence of a wide range of risk-taking behaviour among high-school students in the Cape Peninsula, South Africa, was investigated. In this article, the results for violent behaviour are presented. Cluster sampling techniques produced a sample of 7 340 students from 16 schools in three major education departments. A self-administered questionnaire was completed in a normal school period. Estmates for each education department were weighted to produce an overall estimate. Of the total sample, 12,7%, 9,6% and 13,8% reported that they had been physically injured by another person at school, at home and in other settings, respectively; 11,0% had injured another person during the previous year; 5% had committed an act of vandalism and 9,8% of males and 1,3% of females had carried knives at school. Other trends according to gender, school standard, and home language were identified. Males were more likely to be the perpetrators and victims of violent behaviour; for both genders the extent of victimisation decreased with increasing standard; and fewer Xhosa-speaking students than students in other language groups perpetrated incidents of violent behaviour. The potential for intervention programmes is assessed in a context where much violence is detertnined by sociopolitical factors

Risk-taking behaviour of Cape Peninsula high-school students. Part V. Drug use

The prevalence of a wide range of risk-taking behaviour among high-school students in the Cape Peninsula, South Africa, was investigated. In this article, the results for drug use are presented. Cluster sampling techniques produced a sample of 7 340 students from 16 schools in the three major education departments. A self-administered questionnaire was completed in a normal school period. Estimates for each education departnlent were weighted to produce an overall estimate. Cannabis was the illicit drug most widely used; 7,5% had smoked cannabis, and 2,4% had done so in the previous 7 days. A small subgroup (1,6%) of students had smoked cannabis and methaqualone (Mandrax) together. Reported lifetime use of injectable drugs was 0,5%, and 10,9% had sniffed solvents, 2,6% having done so in the previous 7 days. There were different trends according to gender, standard, and language(s) spoken at home. Of particular note was the Small proportion of Xhosa-speaking females who were involved with drug use. The results suggest that the majority of drug use among school students is experimental. A small number of adolescents abuse drugs and are at risk for its associated problems; intervention is indicated for this group