Characterizing the multi-dimensional reaction dynamics of dihalomethanes using XUV-induced Coulomb explosion imaging.

Site-selective probing of iodine 4d orbitals at 13.1 nm was used to characterize the photolysis of CH2I2 and CH2BrI initiated at 202.5 nm. Time-dependent fragment ion momenta were recorded using Coulomb explosion imaging mass spectrometry and used to determine the structural dynamics of the dissociating molecules. Correlations between these fragment momenta, as well as the onset times of electron transfer reactions between them, indicate that each molecule can undergo neutral three-body photolysis. For CH2I2, the structural evolution of the neutral molecule was simultaneously characterized along the C-I and I-C-I coordinates, demonstrating the sensitivity of these measurements to nuclear motion along multiple degrees of freedom.

The EPIC nutrient database project (ENDB): a first attempt to standardize nutrient databases across the 10 European countries participating in the EPIC study.

OBJECTIVE: This paper describes the ad hoc methodological concepts and procedures developed to improve the comparability of Nutrient databases (NDBs) across the 10 European countries participating in the European Prospective Investigation into Cancer and Nutrition (EPIC). This was required because there is currently no European reference NDB available. DESIGN: A large network involving national compilers, nutritionists and experts on food chemistry and computer science was set up for the 'EPIC Nutrient DataBase' (ENDB) project. A total of 550-1500 foods derived from about 37,000 standardized EPIC 24-h dietary recalls (24-HDRS) were matched as closely as possible to foods available in the 10 national NDBs. The resulting national data sets (NDS) were then successively documented, standardized and evaluated according to common guidelines and using a DataBase Management System specifically designed for this project. The nutrient values of foods unavailable or not readily available in NDSs were approximated by recipe calculation, weighted averaging or adjustment for weight changes and vitamin/mineral losses, using common algorithms. RESULTS: The final ENDB contains about 550-1500 foods depending on the country and 26 common components. Each component value was documented and standardized for unit, mode of expression, definition and chemical method of analysis, as far as possible. Furthermore, the overall completeness of NDSs was improved (>or=99%), particularly for beta-carotene and vitamin E. CONCLUSION: The ENDB constitutes a first real attempt to improve the comparability of NDBs across European countries. This methodological work will provide a useful tool for nutritional research as well as end-user recommendations to improve NDBs in the future.

Mineral oil metal working fluids (MWFs)-development of practical criteria for mist sampling.

Not all mineral oil metalworking fluids (MWFs) in common use form stable airborne mists which can be sampled quantitatively onto a filter. This much has been known for some time but no simple method of identifying oils too volatile for customary filter sampling has been developed. Past work was reviewed and experiments were done to select simple criteria which would enable such oils to be identified. The sampling efficiency for a range of commercial mineral oil MWF were assessed by drawing clean air through spiked filters at 2 l. min(-1) for periods up to 6 h before analysis. The physical properties of MWF are governed by their composition and kinematic viscosity was found to be the most practical and easily available index of the potential for sample loss from the filter. Oils with viscosities greater that 18 cSt (at 40 degrees C) lost less than 5% of their weight, whereas those with viscosities less than 18 cSt gave losses up to 71%. The losses from the MWF were mostly aliphatic hydrocarbons (C(10)-C(18)), but additives such as alkyl benzenes, esters, phenols and terpene odorants were also lost. The main recommendation to arise from the work is that filter sampling can be performed on mineral oils with viscosities of 18 cSt (at 40 degrees C) or more with little evaporative losses from the filter. However, sampling oils with viscosities less than 18 cSt will produce results which may significantly underestimate the true value. Over a quarter of UK mineral oil MWFs are formulated from mineral oils with viscosities less than 18 cSt (at 40 degrees C). The problem of exposure under-estimation and inappropriate exposure sampling could be widespread. Further work is being done on measurement of mixed phase mineral oil mist exposure.

Play position is influenced by knowledge of SIDS sleep position recommendations.

OBJECTIVE: This study determined whether knowledge of sleeping in the prone position as a risk factor for sudden infant death syndrome (SIDS) influences caregivers' positioning of their infants for play and sleep. METHODOLOGY: One hundred caregivers attending Adelaide metropolitan Child Adolescent and Family Health Services (CAFHS) were surveyed by self-administered questionnaire. RESULTS: Ninety-three per cent of parents reported that their knowledge of SIDS influenced infant positioning for sleep and 84% reported they never put their infant in the prone position for sleep. Thirty-seven per cent reported that SIDS knowledge did influence play positioning and 26% reported never placing their infant prone for play. There was a significant association (P = 0.002) between the influence of SIDS knowledge on play positioning and avoidance of the prone position for play. CONCLUSIONS: Community educators may need to clarify that prone positioning for play is not a risk factor for SIDS and that it is desirable for infants to spend supervised wakeful time in the prone position.

Current perspectives on minimal cerebral dysfunction.

Children with minimal cerebral dysfunction (MCD) are a large client group for many paediatric physiotherapists. The increasing number of research papers published in the area of MCD are often complex and difficult to interpret because the children to whom they refer do not form an easily definable, homogeneous group and their prognosis is unclear. This review presents a summary of current findings about MCD and poses a number of questions about physiotherapy intervention. The need for physiotherapists to validate their role in the management of children with MCD is emphasised.

Parent satisfaction with the Minimal Motor Dysfunction Unit: a survey.

This study investigated parent satisfaction with the Minimal Motor Dysfunction Unit (MMDU), a service for clumsy children based in Adelaide. A questionnaire was developed and mailed to 102 parents whose children had attended the MMDU between 1991 and 1993. The response rate was 76 per cent. The level of parent satisfaction with the overall MMDU service was 86 per cent. Parents rated the processes of service delivery and the resulting outcomes as more important to them than structural aspects of the service. Based on parent comments, recommendations were made to assist in further improving the quality of the MMDU service. Parent satisfaction should be investigated as an outcome measure for other paediatric physiotherapy services.

Non-specific prolongation of the effects of general depressants by pyrazole and 4-methylpyrazole.

The liver alcohol dehydrogenase inhibitors, pyrazole and 4-methylpyrazole, have been tested for their ability to prolong drug-induced sleep times in mice. Both drugs (at 1 mmol kg-1 i.p.) prolonged the duration of loss of righting reflex following chloral hydrate, pentobarbitone, barbitone, temazepam and halothane, but not diethyl ether. This suggests that the effects of these pyrazoles are not specific to the inhibition of liver alcohol dehydrogenase.

Ethanol preference in mice following acute or chronic ethanol administration.

C57Bl mice, unlike LACG or BALB mice, show a significant preference for 12% (w/v) ethanol solution compared to water. C57Bl mice which have been rendered tolerant to but not dependent upon ethanol by a programme of enforced ethanol drinking lose this preference on withdrawal of compulsory ethanol. Loss of preference also occurs following one or more acute injections of ethanol ( 4ml /kg) and persists in mice 12 weeks following withdrawal. It is suggested that this long-lasting loss of preference has a CNS basis and is not due merely to taste aversion.

The role of the blood glucose level in determining voluntary ethanol consumption in the LACG and diabetogenic C57BL strains of mice.

The influence of the blood glucose level (BGL) on the voluntary consumption of ethanol by two strains of mice has been investigated. LACG mice show an aversion towards ethanol whereas C57BL mice which are mildly hyperglycaemic show a preference for ethanol. Chronic compulsory ethanol drinking produced hypoglycaemia only in C57BL mice. The oral antidiabetic drugs phenformin and glibenclamide lowered the BGL of C57BL mice which then showed an aversion to ethanol. Raising the BGL of LACG mice by acute alloxan or streptozotocin treatment did not reduce ethanol aversion significantly, but alloxan significantly increased total fluid intake. Diazoxide chronically increased the BGL and slightly increased ethanol consumption in LACG mice. It is concluded that the BGL in C57BL mice may be a factor in determining their innate preference for alcohol. The relationship between alcoholism and diabetes is discussed.

Voluntary ethanol consumption after ethanol and acetaldehyde treatment in alcohol-preferring C57BL mice.

C57BL mice normally show a preference for alcohol solutions compared with water. The effect of chronic ethanol treatment sufficient to produce behavioural tolerance on the voluntary ethanol consumption of C57BL mice was compared with the effect of acute ethanol and acute and chronic administration of acetaldehyde. Chronic treatment with ethanol caused a loss of preference which lasted more than 12 weeks after withdrawal from the treatment. The acute ethanol treatment and the acute and chronic acetaldehyde treatments only produced a transient loss of preference which returned to normal within 1 week of cessation of treatment. The effect of these drugs on liver alcohol dehydrogenase (LAdH) was also examined. Changes in LAdH activity did not correlate with alcohol preference. Possible reasons for the different effects of the drug treatments on alcohol preference are discussed.