Background: One of the goals of this study was to learn the coverage, safety and logistics of a mass vaccination campaign against typhoid fever in children and adults using locally produced typhoid Vi polysaccharide (PS) and group A meningococcal PS vaccines in southern China.

ZnO will become a new pattern optoelectronic material because of its many excellent properties. But the defects in ZnO crystal are the key factors for restricting the luminescence properties of the material. In this paper, we summarized the defect types that exist in ZnO thin films and reviewed on the relationship between the luminescence mechanism and the structure defects of ZnO thin films reported in recent years.

Cross-sectional TEM observation can be used as an important method in the microstructure investigation of thin films. However, the specimen preparation for cross-sectional TEM observation is generally regarded as a challenging task. In this paper, we discussed the preparation of TEM cross-sectional specimens. An example from GaN thin films grown on Si substrate was discussed correspondingly.