Nutritional status, dental caries and tooth eruption in children: a longitudinal study in Cambodia, Indonesia and Lao PDR

Background: Untreated dental caries is reported to affect children's nutritional status and growth, yet evidence on this relationship is conflicting. The aim of this study was to assess the association between dental caries in both the primary and permanent dentition and nutritional status (including underweight, normal weight, overweight and stunting) in children from Cambodia, Indonesia and Lao PDR over a period of 2 years. A second objective was to assess whether nutritional status affects the eruption of permanent teeth. Methods: Data were used from the Fit for School - Health Outcome Study: a cohort study with a follow-up period of 2 years, consisting of children from 82 elementary schools in Cambodia, Indonesia and Lao PDR. From each school, a random sample of six to seven-year-old children was selected. Dental caries and odontogenic infections were assessed using the World Health Organization (WHO) criteria and the pufa-index. Weight and height measurements were converted to BMI-for-age and height-for-age z-scores and categorized into weight status and stunting following WHO standardised procedures. Cross-sectional and longitudinal associations were analysed using the Kruskal Wallis test, Mann Whitney U-test and multivariate logistic and linear regression. Results: Data of 1499 children (mean age at baseline = 6.7 years) were analyzed. Levels of dental caries and odontogenic infections in the primary dentition were significantly highest in underweight children, as well as in stunted children, and lowest in overweight children. Dental caries in six to seven-year old children was also significantly associated with increased odds of being underweight and stunted 2 years later. These associations were not consistently found for dental caries and odontogenic infections in the permanent dentition. Underweight and stunting was significantly associated with a lower number of erupted permanent teeth in children at the age of six to seven-years-old and 2 years later. Conclusions: Underweight and stunted growth are associated with untreated dental caries and a delayed eruption of permanent teeth in children from Cambodia, Indonesia and Lao PDR. Findings suggest that oral health may play an important role in children's growth and general development. Trial registration: The study was restrospectively registered with the German Clinical Trials Register, University of Freiburg (trial registration number: DRKS00004485; date of registration: 26th of February, 2013)

Acquisition and Monitoring System for TEG Characterization

This paper presents an acquisition system for measuring and characterization of thermoelectric generators (TEGs) for energy harvesting purposes on wireless sensors networks (WSNs). This system can monitor and characterize up to three TEGs simultaneously and is comprised of two main electronic circuits: the first one is composed of 12 input channels being three for reading voltage, three for reading current by making use of instrumentation amplifiers (ACS712), and six thermocouples for signal reading (<400∘C). The second electronic circuit consists of a proportional-integral-derivative (PID) controller with two pulse width modulation (PWM) input channels for controlling the heat (thermoresistance) and cooling (controlled cooler) sources, respectively, following a predefined temperature gradient. The TEG measured data for the voltage, current, and temperature can be acquired in real-time with an application written on Delphi language and displayed both through a numeric and graphical display. In order to validate the precision and accuracy two commercial TEG modules (inbC1-127.08HTS) compatible with temperatures up to 200∘C without signal degradation were used in series.The functional prototype of the implemented system had a cost under ≈430 USD, making it suitable where a good knowledge of the electrical characteristics of TEGs is of major interest, especially on cogeneration systems