Depleting the curriculum: teaching digital platforms and curricular impoverishment

The paper aims at showing how curricular complexity tends to be depleted by the use of digital platforms based on the SCORM (Sharable Content Object Reference Model) standard, which was created with the main purpose of recycling content as it is supposed to be independent both from the context of learning and the supporting technology also deemed to be neutral, all surrounded by a rhetoric of innovation and “pedagogical” innovation. The starting point of the discussion is García Perez’s model of Traditional Didactics as a simple tool to show almost graphically that any ancient didactic model is far richer in terms of complexity than the linearity, in disguise most of the times but still visible under a not so sophisticated critical lens, of the interaction human-(reusable) content that is the basis of the SCORM standard. The paper also addresses some of the more common deliberate mix-ups related to those digital platforms, such as learning and teaching, content and learning object, systems of automatic teaching and learning management systems.

Gene delivery using dendrimer/pDNA complexes immobilized in electrospun fibers using the layer-by-layer technique

Tissue engineering is an important branch of regenerative medicine that uses cells, materials (scaffolds), and suitable biochemical and physicochemical factors to improve or replace specific biological functions. In particular, the control of cell behavior (namely, of cell adhesion, proliferation and differentiation) is a key aspect for the design of successful therapeutical approaches. In this study, poly(lactic-co-glycolic acid) (PLGA) fiber mats were prepared using the electrospinning technology (the fiber diameters were in the micrometer range). Furthermore, the electrospun fiber mats thus formed were functionalized using the layer-by- layer (LbL) technique with chitosan and alginate (natural and biodegradable polyelectrolytes having opposite charges) as a mean for the immobilization of pDNA/dendrimer complexes. The polyelectrolyte multilayer deposition was confirmed by fluorescence spectroscopy using fluorescent-labeled polyelectrolytes. The electrospun fiber mats coated with chitosan and alginate were successfully loaded with complexes of pDNA and poly(amidoamine) (PAMAM) dendrimers (generation 5) and were able of releasing them in a controlled manner along time. In addition, these mats supported the adhesion and proliferation of NIH 3T3 cells and of human mesenchymal stem cells (hMSCs) in their surface. Transfection experiments using a pDNA encoding for luciferase showed the ability of the electrospun fiber mats to efficiently serve as gene delivery systems. When a pDNA encoding for bone morphogenetic protein-2 (BMP-2) was used, the osteoblastic differentiation of hMSCs cultured on the surface of the mats was promoted. Taken together, the results revealed that merging the electrospinning technique with the LbL technique, can be a suitable methodology for the creation of biological active matrices for bone tissue engineering.