Balance ability in 7- and 10-year-old children:associations with prenatal lead and cadmium exposure and with blood lead levels in childhood in a prospective birth cohort study

OBJECTIVES: Most studies reporting evidence of adverse effects of lead and cadmium on the ability to balance have been conducted in high-exposure groups or have included adults. The effects of prenatal exposure have not been well studied, nor have the effects in children been directly studied. The aim of the study was to identify the associations of lead (in utero and in childhood) and cadmium (in utero) exposure with the ability to balance in children aged 7 and 10 years. DESIGN: Prospective birth cohort study. PARTICIPANTS: Maternal blood lead (n=4285) and cadmium (n=4286) levels were measured by inductively coupled plasma mass spectrometry in women enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC) during pregnancy. Child lead levels were measured in a subsample of 582 of ALSPAC children at age 30 months. MAIN OUTCOME MEASURES: Children completed a heel-to-toe walking test at 7 years. At 10 years, the children underwent clinical tests of static and dynamic balance. Statistical analysis using SPSS V.19 included logistic regression modelling, comparing categories of ≥ 5 vs <5 µg/dL for lead, and ≥ 1 vs <1 µg/L for cadmium. RESULTS: Balance at age 7 years was not associated with elevated in utero lead or cadmium exposure (adjusted OR for balance dysfunction: Pb 1.01 (95% CI 0.95 to 1.01), n=1732; Cd 0.95 (0.77 to 1.20), n=1734), or with elevated child blood lead level at age 30 months (adjusted OR 0.98 (0.92 to 1.05), n=354). Similarly, neither measures of static nor dynamic balance at age 10 years were associated with in utero lead or cadmium exposure, or child lead level. CONCLUSIONS: These findings do not provide any evidence of an association of prenatal exposure to lead or cadmium, or lead levels in childhood, on balance ability in children. Confirmation in other cohorts is needed.

Systematic and heuristic processing of majority and minority-endorsed messages:the effects of varying outcome relevance and levels of orientation on attitude and message processing

Two experiments investigated the conditions under which majority and minority sources instigate systematic processing of their messages. Both experiments crossed source status (majority vs. minority) with message quality (strong vs. weak arguments). In each experiment, message elaboration was manipulated by varying either motivational (outcome relevance, Experiment 1) or cognitive (orientating tasks, Experiment 2) factors. The results showed that when either motivational or cognitive factors encouraged low message elaboration, there was heuristic acceptance of the majority position without detailed message processing. When the level of message elaboration was intermediate, there was message processing only for the minority source. Finally, when message elaboration was high, there was message processing for both source conditions. These results show that majority and minority influence is sensitive to motivational and cognitive factors that constrain or enhance message elaboration and that both sources can lead to systematic processing under specific circumstances. © 2007 by the Society for Personality and Social Psychology, Inc.

Background levels of urban land contamination

The research work reported in this thesis is concerned with the development and application of an urban scale sampling methodology for measuring and assessing background levels of heavy metal soil contamination in large and varied urban areas. The policy context of the work is broadly the environmental health problems posed by contaminated land and their implications for urban development planning. Within this wider policy context, the emphasis in the research has been placed on issues, related to the determination and application of 'guidelines' for assessing the significance of contaminated land for environmental planning. In concentrating on background levels of land contamination, the research responds to the need for additional techniques which address both the problems of measuring soil contamination at the urban scale and which are also capable of providing detailed information for use in the assessment of contaminated sites. Therefore, a key component of the work has been the development of a land-use based sampling framework for generating spatially comprehensive data on heavy metals in soil. The utility of the information output of the sampling method is demonstrated in two alternative ways. Firstly, it has been used to map the existing pattern of typical levels of heavy metals in urban soils. Secondly, it can be used to generate both generalised data in the form of 'reference levels' from which the overall significance of .background contamination may be assessed and detailed data, termed 'normal limit levels' for use in the assessment of site specific investigation data. The fieldwork was conducted in the West Midlands Metropolitan County and surface soil has been sampled and analysed for a measure of plant-available' and 'total' lead cadmium, copper and zinc. The research contrasts with much of the previous work on contaminated land which has generally concentrated on either the detailed investigation of individual sites suspected of being contaminated or the appraisal of land contamination resulting from specific point sources.

Reduction of noise levels in vaccum cleaners

The work described in this thesis is directed towards the reduction of noise levels in the Hoover Turbopower upright vacuum cleaner. The experimental work embodies a study of such factors as the application of noise source identification techniques, investigation of the noise generating principles for each major source and evaluation of the noise reducing treatments. It was found that the design of the vacuum cleaner had not been optimised from the standpoint of noise emission. Important factors such as noise `windows', isolation of vibration at the source, panel rattle, resonances and critical speeds had not been considered. Therefore, a number of experimentally validated treatments are proposed. Their noise reduction benefit together with material and tooling costs are presented. The solutions to the noise problems were evaluated on a standard Turbopower and the sound power level of the cleaner was reduced from 87.5 dB(A) to 80.4 db(A) at a cost of 93.6 pence per cleaner.The designers' lack of experience in noise reduction was identified as one of the factors for the low priority given to noise during design of the cleaner. Consequently, the fundamentals of acoustics, principles of noise prediction and absorption and guidelines for good acoustical design were collated into a Handbook and circulated at Hoover plc.Mechanical variations during production of the motor and the cleaner were found to be important. These caused a vast spread in the noise levels of the cleaners. Subsequently, the manufacturing processes were briefly studied to identify their source and recommendations for improvement are made.Noise of a product is quality related and a high level of noise is considered to be a bad feature. This project suggested that the noise level be used constructively both as a test on the production line to identify cleaners above a certain noise level and also to promote the product by `designing' the characteristics of the sound so that the appliance is pleasant to the user. This project showed that good noise control principles should be implemented early in the design stage.As yet there are no mandatory noise limits or noise-labelling requirements for household appliances. However, the literature suggests that noise-labelling is likely in the near future and the requirement will be to display the A-weighted sound power level. However, the `noys' scale of perceived noisiness was found more appropriate to the rating of appliance noise both as it is linear and therefore, a sound level that seems twice as loud is twice the value in noys and also takes into consideration the presence of pure tones, which even in the absence of a high noise level can lead to annoyance.

ICT and internet use at the household levels:a melting pot of sub-optimum decision making in the case of E-Grocery shopping

Research shows that consumers are readily embracing the Internet to buy products. This paper proposes that, in the case of grocery shopping, this may lead to sub-optimal decisions at the household level. Decisions online on what, where and from who to buy are normally taken by one individual. In the case of grocery shopping, decisions, however, need to be ‘vetted’ by ‘other’ individuals within the household. The ‘household wide related’ decisions influence how information technologies and systems for commerce should be designed and managed for optimum decision making. This paper argues, unlike previous research, that e-grocery retailing is failing to grow to its full potential not solely because of the ‘classical’ hazards and perceived risks associated with doing grocery shopping online but because e-grocery retailing strategy has failed to acknowledge the micro-household level specificities that affect decision making. Our exploratory research is based on empirical evidence which were collected through telephone interviews. We offer an insight into how e-grocery ‘fits’ and is ‘disrupted’ by the reality of day to day consumption decision making at the household level. Our main finding is to advocate a more role-neutral, multi-user and multi-technology approach to e-grocery shopping which re-defines the concept of the main shopper/decision maker thereby reconceptualising the ‘shopping logic’ for grocery products.

Individual variability analysis of fluorescence parameters measured in skin with different levels of nutritive blood flow

Fluorescence spectroscopy has recently become more common in clinical medicine. However, there are still many unresolved issues related to the methodology and implementation of instruments with this technology. In this study, we aimed to assess individual variability of fluorescence parameters of endogenous markers (NADH, FAD, etc.) measured by fluorescent spectroscopy (FS) in situ and to analyse the factors that lead to a significant scatter of results. Most studied fluorophores have an acceptable scatter of values (mostly up to 30%) for diagnostic purposes. Here we provide evidence that the level of blood volume in tissue impacts FS data with a significant inverse correlation. The distribution function of the fluorescence intensity and the fluorescent contrast coefficient values are a function of the normal distribution for most of the studied fluorophores and the redox ratio. The effects of various physiological (different content of skin melanin) and technical (characteristics of optical filters) factors on the measurement results were additionally studied.The data on the variability of the measurement results in FS should be considered when interpreting the diagnostic parameters, as well as when developing new algorithms for data processing and FS devices.