IMECE2008-66292 EXPERIMENTAL ANALYSIS OF VIBRATION OF MICROMACHINED RESONATORS

ABSTRACT Among many different mechanisms that are used for excitation and detection of vibration of micro-beam resonators, electrostatic comb-drives have the benefit of simplicity and large range of linear operation. The disadvantage of using comb-drives is the effect of added mass to the beam; however, the analytical model of the beam-mass system predicts that this shortcoming can be overcome by proper adjustment of the mass, rotary inertia, and location of the comb-drive. In addition, the analytical model can predict the effect of the axial force of the beam on the resonance frequencies. In this paper, the results of the experiments on two resonators are presented. These results are used to verify the validity of the analytical model and finding its parameters. Very close agreement between the theory and experiment is observed. The residual stress of the MEMS structural layer is measured using the calibrated analytical model parameters

Annual Feedback Is an Effective Tool for a Sustained Increase in Calcium Intake among Older Women

We aimed to optimize calcium intake among the 2,000+ older women taking part in the Vital D study. Calcium supplementation was not included in the study protocol. Our hypothesis was that annual feedback of calcium intake and informing women of strategies to improve calcium intake can lead to a sustained increase in the proportion of women who consume adequate levels of the mineral. Calcium intake was assessed on an annual basis using a validated short food frequency questionnaire (FFQ). Supplemental calcium intake was added to the dietary estimate. Participants and their nominated doctor were sent a letter that the participant’s estimated daily calcium intake was adequate or inadequate based on a cutoff threshold of 800 mg/day. General brief statements outlining the importance of an adequate calcium intake and bone health were included in all letters. At baseline, the median daily consumption of calcium was 980 mg/day and 67 percent of 1,951 participants had calcium intake of at least 800 mg per day. Of the 644 older women advised of an inadequate calcium intake at baseline (<800 mg/day), 386 (60%) had increased their intake by at least 100 mg/day when re-assessed twelve months later. This desirable change was sustained at 24 months after baseline with almost half of these women (303/644) consuming over 800 mg calcium per day. This study devised an efficient method to provide feedback on calcium intake to over 2,000 older women. The improvements were modest but significant and most apparent in those with a low intake at baseline. The decreased proportion of these women with an inadequate intake of calcium 12- and 24-months later, suggests this might be a practical, low cost strategy to maintain an adequate calcium intake among older women

Root canal morphology of primary maxillary second molars:a micro-computed tomography analysis

Aim Successful endodontic treatment of primary teeth requires comprehensive knowledge and understanding of root canal morphology. The purpose of this study was to investigate the root canal configurations of primary maxillary second molars using micro-computed tomography. Methods Extracted human primary maxillary second molars (n = 57) were scanned using micro-computed tomography and reconstructed to produce three-dimensional models. Each root canal system was analysed qualitatively according to Vertucci's classification. Results 22.8% (n = 13) of the sample presented with the fusion of the disto-buccal and palatal roots; of these, Type V was the most prevalent classification. For teeth with three separate roots (n = 44), the most common root canal type was Type 1 for the palatal canal (100%) and disto-buccal canal (77.3%) and Type V for the mesio-buccal canal (36.4%). Overall, 7% (n = 4) of mesio-buccal canals were 'unclassifiable'. Conclusion The root canal systems of primary maxillary second molars were not only complex but had a range of configurations that may contribute to unfavourable clinical outcomes after endodontic treatment

An exploration of knowledge, attitudes and advice given by health professionals to parents in Ireland about the introduction of solid foods. A pilot study

<p>Abstract</p> <p>Background</p> <p>For the purposes of this paper "weaning is defined as the introduction of the first solid foods to infants". Global recommendations by the World Health Organisation (WHO) recommend that all infants be exclusively breast-fed for the first six months of life. No global recommendations have been made for formula fed infants. In Europe it is recommended that weaning foods should be introduced between 18 weeks and 26 weeks regardless of whether infants are breast or formula fed. In the United Kingdom it is recommended that solids be introduced at around six-months for both breast and formula fed infants. In Ireland official guidelines recommend that breast fed infants should be introduced solids at 6 months of age while for formula fed infants the recommendation is for 4 months. The disparity between these global, European, UK and local recommendations may be a source of confusion for parents and health care professional based in Ireland. Emerging evidence suggests that babies in Ireland are given solid foods before the recommended age but there has been little investigation of the weaning advice provided by health professionals. Since community health professionals have routine parent interactions in the pre-weaning and early-weaning period and hence are in a unique position to positively influence parental weaning decisions, this study aimed to explore their knowledge, attitudes and advice practices about weaning.</p> <p>Methods</p> <p>A mixed-methods approach was used for the research, commencing with a multi-disciplinary focus group to guide and develop a questionnaire. Questionnaires were then distributed in a postal survey to General Practitioners (GPs) (<it>n </it>179), Practice Nurses (PNs) (<it>n </it>121), Public Health Nurses (PHNs) (<it>n </it>107) and Community Dieticians (CDs) (<it>n </it>8).</p> <p>Results</p> <p>The results indicate varying levels of knowledge of official weaning recommendations and a variety of advice practices. CDs and PHNs acknowledged a clear role in providing weaning advice while demonstrating high confidence levels in providing this advice. However, 19% of PNs and 7% of GP respondents did not acknowledge that they have a role in providing weaning advice to parents; even though Health Service Executive (HSE) written literature given to parents states that they should seek information from PNs and GPs.</p> <p>Conclusion</p> <p>Small pockets of misinformation about the introduction of solid foods persist amongst health professionals which may lead to inconsistent advice for parents. Further research is needed.</p

The stone adze and obsidian assemblage from the Talasiu site, Kingdom of Tonga

Typological and geochemical analyses of stone adzes and other stone tools have played a significant role in identifying directionality of colonisation movements in early migratory events in the Western Pacific. In later phases of Polynesian prehistory, stone adzes are important status goods which show substantial spatial and temporal variation. However, there is a debate when standardisation of form and manufacture appeared, whether it can be seen in earliest populations colonising the Pacific or whether it is a later development. We present in this paper a stone adze and obsidian tool assemblage from an early Ancestral Polynesian Society Talasiu site on Tongatapu, Kingdom of Tonga. The site shows a wide variety of adze types; however, if raw material origin is taken into account, emerging standardisation in adze form might be detected. We also show that Tongatapu was strongly connected in a network of interaction to islands to the North, particularly Samoa, suggesting that these islands had permanent populations

Seroprevalence of human herpesvirus-8 (HHV-8) in countries of Southeast Asia compared to the USA, the Caribbean and Africa

Seroprevalence of HHV-8 has been studied in Malaysia, India, Sri Lanka, Thailand, Trinidad, Jamaica and the USA, in both healthy individuals and those infected with HIV. Seroprevalence was found to be low in these countries in both the healthy and the HIV-infected populations. This correlates with the fact that hardly any AIDS-related Kaposi’s sarcoma has been reported in these countries. In contrast, the African countries of Ghana, Uganda and Zambia showed high seroprevalences in both healthy and HIV-infected populations. This suggests that human herpes virus-8 (HHV-8) may be either a recently introduced virus or one that has extremely low infectivity. Nasopharyngeal and oral carcinoma patients from Malaysia, Hong Kong and Sri Lanka who have very high EBV titres show that only 3/82 (3.7%) have antibody to HHV-8, demonstrating that there is little, if any, cross-reactivity between antibodies to these two gamma viruses. © 1999 Cancer Research Campaig

The NOURISH randomised control trial: Positive feeding practices and food preferences in early childhood - a primary prevention program for childhood obesity

Background Primary prevention of childhood overweight is an international priority. In Australia 20-25% of 2-8 year olds are already overweight. These children are at substantially increased the risk of becoming overweight adults, with attendant increased risk of morbidity and mortality. Early feeding practices determine infant exposure to food (type, amount, frequency) and include responses (eg coercion) to infant feeding behaviour (eg. food refusal). There is correlational evidence linking parenting style and early feeding practices to child eating behaviour and weight status. A focus on early feeding is consistent with the national focus on early childhood as the foundation for life-long health and well being. The NOURISH trial aims to implement and evaluate a community-based intervention to promote early feeding practices that will foster healthy food preferences and intake and preserve the innate capacity to self-regulate food intake in young children. Methods/Design This randomised controlled trial (RCT) aims to recruit 820 first-time mothers and their healthy term infants. A consecutive sample of eligible mothers will be approached postnatally at major maternity hospitals in Brisbane and Adelaide. Initial consent will be for re-contact for full enrolment when the infants are 4-7 months old. Individual mother- infant dyads will be randomised to usual care or the intervention. The intervention will provide anticipatory guidance via two modules of six fortnightly parent education and peer support group sessions, each followed by six months of regular maintenance contact. The modules will commence when the infants are aged 4-7 and 13-16 months to coincide with establishment of solid feeding, and autonomy and independence, respectively. Outcome measures will be assessed at baseline, with follow up at nine and 18 months. These will include infant intake (type and amount of foods), food preferences, feeding behaviour and growth and self-reported maternal feeding practices and parenting practices and efficacy. Covariates will include sociodemographics, infant feeding mode and temperament, maternal weight status and weight concern and child care exposure. Discussion Despite the strong rationale to focus on parents’ early feeding practices as a key determinant of child food preferences, intake and self-regulatory capacity, prospective longitudinal and intervention studies are rare. This trial will be amongst to provide Level II evidence regarding the impact of an intervention (commencing prior to age 12 months) on children’s eating patterns and behaviours. Trial Registration: ACTRN1260800005639

Association of food security status with overweight and dietary intake: exploration of White British and Pakistani-origin families in the Born in Bradford cohort.

BACKGROUND: Food insecurity has been associated with dietary intake and weight status in UK adults and children although results have been mixed and ethnicity has not been explored. We aimed to compare prevalence and trajectories of weight and dietary intakes among food secure and insecure White British and Pakistani-origin families. METHODS: At 12 months postpartum, mothers in the Born in Bradford cohort completed a questionnaire on food security status and a food frequency questionnaire (FFQ) assessing their child's intake in the previous month; at 18 months postpartum, mothers completed a short-form FFQ assessing dietary intake in the previous 12 months. Weights and heights of mothers and infants were assessed at 12-, 24-, and 36-months postpartum, with an additional measurement of children taken at 4-5 years. Associations between food security status and dietary intakes were assessed using Wilcoxon-Mann-Whitney for continuous variables and χ2 or Fisher's exact tests for categorical variables. Quantile and logistic regression were used to determine dietary intakes adjusting for mother's age. Linear mixed effects models were used to assess longitudinal changes in body mass index (BMI) in mothers and BMI z-scores in children. RESULTS: At 12 months postpartum, White British mothers reported more food insecurity than Pakistani-origin mothers (11% vs 7%; p < 0.01) and more food insecure mothers were overweight. Between 12 and 36 months postpartum, BMI increased more among food insecure Pakistani-origin mothers (β = 0.77 units, [95% Confidence Interval [CI]: 0.40, 1.10]) than food secure (β = 0.44 units, 95% CI: 0.33, 0.55). This was also found in Pakistani-origin children (BMI z-score: food insecure β = 0.40 units, 95% CI: 0.22, 0.59; food secure β = 0.25 units, 95% CI: 0.20, 0.29). No significant increases in BMI were observed for food secure or insecure White British mothers while BMI z-score increased by 0.17 (95% CI: 0.13, 0.21) for food secure White British children. Food insecure mothers and children had dietary intakes of poorer quality, with fewer vegetables and higher consumption of sugar-sweetened drinks. CONCLUSIONS: Food security status is associated with body weight and dietary intakes differentially by ethnicity. These are important considerations for developing targeted interventions