No abstract

An air embolism is induced by intravascular bubbles that block the blood flow in vessels, which causes a high risk of pulmonary hypertension and myocardial and cerebral infarction. However, it is still unclear how a moving bubble is stopped in the blood flow to form an air embolism in small vessels. In this work, microfluidic experiments, in vivo and in vitro, are performed in small vessels, where bubbles are seen to deform and stop gradually in the flow. A clot is always found to originate at the tail of a moving bubble, which is attributed to the special flow field around the bubble. As the clot grows, it breaks the lubrication film between the bubble and the channel wall; thus, the friction force is increased to stop the bubble. This study illustrates the stopping process of elongated bubbles in small vessels and brings insight into the formation of air embolism.

Fluids containing high concentration polymers, sols, nanoparticles, etc., usually have high viscosities, and high-viscosity fluids are difficult to be encapsulated into uniform droplets. Here we report a surface-controlled breakup method to generate droplets directly from various aqueous and nonaqueous fluids with viscosities of 1.0 to 11.9 Pa s and a dispersed-to-continuous viscosity ratio up to 1000, whereas the volume fraction of droplets up to 50% can be achieved. It provides a straightforward method to encapsulate high viscosity fluids, in a well-controlled manner in the rapid developing droplet-based applications, including materials synthesis, drug delivery, cell assay, bioengineering, etc.

Aux/IAA gene family is a kind of transcription factors in plants, which plays a regulatory role in the process of auxin regulating plant growth. In this study, the structural characteristics and gene expression patterns of Aux/IAA transcription factors in maize (Zea mays L.) were analyzed by bioinformatics method, and 32 Aux/IAA genes from Arabidopsis and 40 Aux/IAA genes from maize were screened for phylogenetic evolution. It was inferred that the gene family was an ancient and huge gene family by evolutionary tree. The numbers of Aux/IAA genes distributed on chromosome 3 and 6 are the largest. Subcellular localization prediction indicated that the gene family mainly played a role in the nucleus. Thermogram analysis showed that a small number of genes were highly expressed in specific tissues. In addition, GRMZM2G115357 was highly expressed under the condition of high osmotic pressure, which might play a role in the process of resistance to high osmotic stress in maize. The results of this study promote the understanding of Aux/IAA family genes and lay a foundation for the functional study of Aux/IAA family genes at the molecular level.

By means of the concept DE we analyze the responses of a HH neuron to two types of spike-train inputs. Two characteristic quantities can be extracted, which can reflect partially the dynamical process of a HH neuron.