3D printed Lego®-like modular microfluidic devices based on capillary driving.

The field of how to rapidly assemble microfluidics with modular components continuously attracts researchers' attention, however, extra efforts must be devoted to solving the problems of leaking and aligning between individual modules. This paper presents a novel type of modular microfluidic device, driven by capillary force. There is no necessity for a strict seal or special alignment, and its open structures make it easy to integrate various stents and reactants. The key rationale for this method is to print different functional modules with a low-cost three-dimensional (3D) printer, then fill the channels with capillary materials and assemble them with plugs like Lego® bricks. This rapidly reconstructed modular microfluidic device consists of a variety of common functional modules and other personalized modules, each module having a unified standard interface for easy assembly. As it can be printed by a desktop 3D printer, the manufacturing process is simple and efficient, with controllable regulation of the flow channel scale. Through diverse combinations of different modules, a variety of different functions can be achieved, without duplicating the manufacturing process. A single module can also be taken out for testing and analysis. What's more, combined with basic circuit components, it can serve as a low-cost Lego®-like modular microfluidic circuits. As a proof of concept, the modular microfluidic device has been successfully demonstrated and used for stent degradation and cell cultures, revealing the potential use of this method in both chemical and biological research.

Influencing factors on underweight and stunting among children aged 0-3 years in rural areas from ten provinces in China / 中华流行病学杂志

Objective To analysis the influencing factors on underweight and stunting among children aged 0-3 years in rural areas from ten provinces in China.Methods Children under study were identified by multi-stage stratified cluster from rural areas of ten provinces in China.The ascertainment methods mainly included questionnaire and anthropometric measurements.Results There were 58 926 children under investigation,with 50.91％ were boys.The overall rates on underweight and stunting were 5.05％ and 10.49％ respectively.The rate in the 6 month-olds (1.97％,3.79％ ) was the lowest,while the highest were in the 24 month-olds (7.80％) and the 36 month-olds (16.83％).Age,sex,birth weight,gestational weeks as well as maternal education and fathers' schooling were factors significantly related to childhood underweight and stunting (P＜0.0001).Conclusion The status of underweight and stunting among children aged 0-3 years in rural areas was impressive,with birth weight was the key factor influencing the growth of children.Perinatal health care should be improved to promote the growth of children.