Hence the developmental systems model has a promising future. From a developmental perspective, adolescents within sellekchem their natural contexts need to be studied in tandem and over time. This requires more sophisticated research designs. With respect to the cultivation of resilience among adolescents, one implication is that as adolescents develop toward adulthood, adverse situations will change as will their need for competencies. Therefore, a good person-stage-environment fit is required to keep pace with these changing needs and situations so that intervention programs remain developmentally appropriate to the target population. Furthermore, protective factors operate across different levels. In order for research to be realistic and interventions to be effective, we must consider how individual capacity interplays with external protective factors.

There is a need for more research on the interactions among adversities, internal and external protective factors, and interventions.
Rapid prototyping is a manufacturing technology used in many industries to develop high fidelity three-dimensional structures from source image data. Medical applications have generally been within an academic centre or research environment, as support costs (expertise, software, and equipment) have been large. Applications within clinical practice include preoperative planning/conceptualisation, procedure rehearsal [1�C7], and educational tools for teaching [8] and patient communication [9].The idea of using computed tomography (CT) data to build physical models was put forward by Alberti in 1979 [10].

In 1979, a polystyrene model of a pelvis was constructed so that a custom-made metal implant could be designed for a patient with fibrosarcoma [11]. In the 1980s there was considerable progress in model building from CT data using polystyrene and then the stronger Cilengitide polyurethane foam [12]. Milled models were quite accurate for larger structures, for example, being subject to average deviation of only 1.6mm for distances between high-resolution structures [12, 13]. By 1985, 3D imaging had progressed to a level at which image fidelity was sufficient for more widespread clinical use at academic centres [14, 15] to plan for complex surgery, especially using computed tomography (CT) of the craniofacial and maxillofacial regions [6, 13, 16, 17]. In 1994, Zonneveld and Fukuta highlighted the difficulty in data conversion from that of standard ��slice-oriented�� segmented object files to formats used in model manufacture [15].