Application of the ratio of the radiopaque calcified area to the dental follicle (RCA/DF) for dental age assessment on orthopantomograms.

OBJECTIVES: This study aimed at exploring a new tooth development evaluation method for age assessment and investigating the dynamic alteration and potential trend of tooth development by orthopantomograms (OPGs), in order to provide references for tooth development prediction and forensic purpose. MATERIALS AND METHODS: A total of 132 OPGs of children aged 3-8 years were collected. The developmental stages of the permanent mandibular second molar (M2)were evaluated by experienced examiners according to the Nolla method and Mimics software, respectively. Quantitative analysis of the ratio of the radiopaque calcified area to the dental follicle (RCA/DF) in different stages, ages, sexes and quadrants were evaluated and compared via descriptive statistics and Spearman's correlation coefficient analysis. RESULTS: There was a strong, positive correlation between the examiners' evaluation and mimics analysis results. With the age increased, the Nolla stage of M2 observed by OPGs increased, and the RCA/DF showed increased trends both in males and females. There were significant differences of the RCA/DF of the M2 at various ages. The tooth calcification development of female was 9.08% earlier than that of male between 3 and 8 years old. However, teeth of male seemed to develop faster than that of female during this period. There was no significant difference between left and right quadrant either according to the Nolla stage or RCA/DF. CONCLUSIONS: The RCA/DF value obtained from OPGs of the developmental mandibular second permanent molars could be used as a reliable indicator for tooth maturity and age estimation in children aged 3-8 years. CLINICAL RELEVANCE: Age assessment based on radiographs is considered as a reliable and efficient indicator for judging different types of malocclusion, making suitable orthodontic treatment plan, deciding the extraction time of retained deciduous teeth in clinic practice.

Using expert decision-making to establish indicators of urban friendliness for walking environments: a multidisciplinary assessment.

BACKGROUND: Numerous studies have suggested that friendly walking environments positively affect physical activity and health. Creating friendly walking environments in urban areas is a complex and wide-ranging topic, and no study has yet established a set of assessment indicators by drawing on the expertise of various disciplines. This study uses a multiple-criteria decision-making technique to elucidate the environmental factors that affect the friendliness of the walking environment. METHODS: We conducted a two-phase expert questionnaire survey. Experts from the government sector, as well as the academic disciplines of urban planning, transportation, architecture, and landscape design, were recruited to establish a set of walking environment indicators; the degrees of importance assigned to these indicators by the experts were subsequently compared. In phase 1, the fuzzy Delphi method was used by 20 experts, whose responses were used to identify four dimensions and 22 indicators. In phase 2, an analytical network process approach was performed by 16 experts to determine the weights of the dimensions and indicators. RESULTS: The results revealed that all of the experts ranked the four dimensions in the order of safety > facilities > aesthetics > land use mix. Of the 22 indicators, land use-diversity, land use-access, sidewalk width, sidewalk continuity, and cleanliness were considered the most important. CONCLUSIONS: The results provide a reference for the management of walking environments by promoting pedestrian-oriented environments and public health.

Yeast Surface-Displayed H5N1 Avian Influenza Vaccines.

Highly pathogenic H5N1 avian influenza viruses pose a pandemic threat to human health. A rapid vaccine production against fast outbreak is desired. We report, herein, a paradigm-shift influenza vaccine technology by presenting H5N1 hemagglutinin (HA) to the surface of yeast. We demonstrated, for the first time, that the HA surface-presented yeast can be used as influenza vaccines to elicit both humoral and cell-mediated immunity in mice. The HI titer of antisera reached up to 128 in vaccinated mice. A high level of H5N1 HA-specific IgG1 and IgG2a antibody production was detected after boost immunization. Furthermore, we demonstrated that the yeast surface-displayed HA preserves its antigenic sites. It preferentially binds to both avian- and human-type receptors. In addition, the vaccine exhibited high cross-reactivity to both homologous and heterologous H5N1 viruses. A high level production of anti-HA antibodies was detected in the mice five months after vaccination. Finally, our animal experimental results indicated that the yeast vaccine offered complete protection of mice from lethal H5N1 virus challenge. No severe side effect of yeast vaccines was noted in animal studies. This new technology allows for rapid and large-scale production of influenza vaccines for prepandemic preparation.

Cash incentives improve participation rate in a face-to-face survey: an intervention study.

OBJECTIVES: Our study examined the effect of a ChinaYuan (CNY) 10 cash incentive on the participation rate in a face-to-face health survey among the general Chinese population. STUDY DESIGN AND SETTING: Subjects older than 15 years of age and had been living in the two selected districts for more than 6 months were selected using multistage random sampling. Participants from only one district received a cash incentive (CNY 10) for completing the survey. RESULTS: The participation rates in the nonincentive and incentive groups were 39.9% and 61.2%, respectively, P < 0.01. In the nonincentive group, the 65-74 years age group had the highest participation rate (54.4%); no significant difference was found between men (39.4%) and women (40.5%), P = 0.59. In the incentive group, the highest participation rate was observed in the ≥75 years (78.1%) age group. The cost for a completed interview was CNY 34.5 in the incentive group and CNY 35.8 in the nonincentive group. CONCLUSION: Cash incentives might increase participation rates in face-to-face surveys in China. The absolute cost was higher for the incentive group, whereas cost for a completed interview was actually the lowest. Furthermore, participation rate did not differ between men and women, but elders were more likely to participate in health surveys.