A Laplace pressure based microfluidic trap for passive droplet trapping and controlled release

Here, we present a microfluidic droplet trap that takes advantage of the net Laplace pressure force generated when a droplet is differentially constricted. Mathematical simulations were first used to understand the working range of the component; followed by finite element modeling using the CFD software package to further characterize the behavior of the system. Controlled release of the trapped droplets is also demonstrated through both a mechanical method and a chemical method that manipulates the total pressure exerted on the trapped droplet. The unique design of this trapping device also provides the capability for selection of a single droplet from a train, as well as droplet fusion.     

Concept drift detection and adaptation with hierarchical hypothesis testing

A fundamental issue for statistical classification models in a streaming environment is that the joint distribution between predictor and response variables changes over time (a phenomenon also known as concept drifts), such that their classification performance deteriorates dramatically. In this paper, we first present a hierarchical hypothesis testing (HHT) framework that can detect and also adapt to various concept drift types (e.g., recurrent or irregular, gradual or abrupt), even in the presence of imbalanced data labels. A novel concept drift detector, namely Hierarchical Linear Four Rates (HLFR), is implemented under the HHT framework thereafter. By substituting a widely-acknowledged retraining scheme with an adaptive training strategy, we further demonstrate that the concept drift adaptation capability of HLFR can be significantly boosted. The theoretical analysis on the Type-I and Type-II errors of HLFR is also performed. Experiments on both simulated and real-world datasets illustrate that our methods outperform state-of-the-art methods in terms of detection precision, detection delay as well as the adaptability across different concept drift types.     

Emotion dialogues between mothers and children at 4.5 and 7.5 years: relations with children's attachment at 1 year

It was examined whether secure infant-mother attachment contributes to emotionally congruent and organized mother-child dialogues about emotions in later years. The attachment of 99 children was assessed using the Strange Situation at the age of 1 year and their emotion dialogues with their mothers were assessed at the ages of 4.5 and 7.5 years. Dialogues were about past emotional events and separation of a child from parents, and were classified into an emotionally matched group or 1 of 3 non-emotionally matched groups. Security in infancy was associated with emotionally matched dialogues at the age of 4.5; there was moderate stability in dialogues between 4.5 and 7.5 years; and infant attachment predicted dialogues at 7.5 beyond the prediction offered by age 4.5 dialogues.