733
Preliminary studies along this line can be found in Refs.. iii ) Topological design of the lattice structures that can be easily produced by AM and exhibit anisotropic mechanical properties similar to human bones is another promising direction , despite that the fact that there has been extensive research on topology optimization based on continuum models .
 material: be; engineering feature: Topological design; engineering feature: lattice structures; material: be; manufacturing process: AM; machanical property: anisotropic; concept or principle: properties; concept or principle: research; engineering feature: topology optimization; concept or principle: continuum models
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: manufacturing standard, machanical property, manufacturing process, material, engineering feature, process parameter, machine or equipment, application, process characterization, enabling technology, biomedical, concept or principle 
Text: {0} 
Answer:
 material: be; engineering feature: Topological design; engineering feature: lattice structures; material: be; manufacturing process: AM; machanical property: anisotropic; concept or principle: properties; concept or principle: research; engineering feature: topology optimization; concept or principle: continuum models