| 1. |
- Hertzberg, Joachim, et al.
(författare)
-
The RACE Project : Robustness by Autonomous Competence Enhancement
- 2014
-
Ingår i: Künstliche Intelligenz. - : Springer Berlin/Heidelberg. - 0933-1875 .- 1610-1987. ; 28:4, s. 297-304
-
Tidskriftsartikel (refereegranskat)abstract
- This paper reports on the aims, the approach, and the results of the European project RACE. The project aim was to enhance the behavior of an autonomous robot by having the robot learn from conceptualized experiences of previous performance, based on initial models of the domain and its own actions in it. This paper introduces the general system architecture; it then sketches some results in detail regarding hybrid reasoning and planning used in RACE, and instances of learning from the experiences of real robot task execution. Enhancement of robot competence is operationalized in terms of performance quality and description length of the robot instructions, and such enhancement is shown to result from the RACE system.
|
|
| 2. |
- Mohagheghiyan, Kiana, et al.
(författare)
-
Gelatin-coated mesoporous forsterite scaffold for bone tissue engineering
- 2024
-
Ingår i: Ceramics International. - : Elsevier. - 0272-8842 .- 1873-3956. ; 50:8, s. 13526-13535
-
Tidskriftsartikel (refereegranskat)abstract
- This study aims to develop a mesoporous forsterite spheres-based scaffold for bone tissue regeneration. To achieve this goal, mesoporous forsterite spheres were fabricated using alginate (gel-forming agent) and activated charcoal (porogen). The impact of carbon concentration (2, 5, 10, and 20 wt %) and sintering temperature (1100 and 1200 °C) on the structural properties of mesoporous forsterite spheres was investigated. Additionally, gelatin coatings were applied to modify these spheres. Forsterite microspheres with a particle size of 2.43 ± 0.22 mm were successfully produced, exhibiting varying pore sizes based on the sintering temperature and carbon content. Notably, mesoporous forsterite spheres synthesized using 5 wt% carbon and sintered at 1200 °C displayed uniform morphology, a minor average diameter (2.4 ± 0.3 mm(, and an average pore size of 2.7 ± 0.9 μm. These optimized forsterite spheres exhibited mesoporous structures with superior surface area (2.93 m2g-1) and pore volume (0.009–0.048 cm3g-1). Furthermore, the gelatin coating, with an average thickness of 160 μm, was effectively applied to the forsterite spheres. The gelatin coating reduced the surface area (1.40 m2g-1), pore volume (0.003 cm3g-1), and average pore diameter to 9.26 nm, maintaining the mesoporous structure. Both mesoporous forsterite spheres successfully induced bone-like apatite formation in vitro during a 21-day immersion in simulated body fluid. Moreover, while both forsterite-based spheres exhibited cytocompatibility with MG63 cells (cell viability >80 %), the gelatin coating significantly enhanced osteogenic differentiation (1.29 times). In conclusion, gelatin-coated mesoporous forsterite spheres exhibit promising potential as bioactive filling scaffolds for bone tissue regeneration.
|
|
| 3. |
- Mokhtari, Hamidreza, et al.
(författare)
-
Recent Advances in Chemically-Modified and Hybrid Carrageenan-Based Platforms for Drug Delivery, Wound Healing, and Tissue Engineering
- 2021
-
Ingår i: Polymers. - : MDPI. - 2073-4360. ; 13:11
-
Forskningsöversikt (refereegranskat)abstract
- Recently, many studies have focused on carrageenan-based hydrogels for biomedical applications thanks to their intrinsic properties, including biodegradability, biocompatibility, resembling native glycosaminoglycans, antioxidants, antitumor, immunomodulatory, and anticoagulant properties. They can easily change to three-dimensional hydrogels using a simple ionic crosslinking process. However, there are some limitations, including the uncontrollable exchange of ions and the formation of a brittle hydrogel, which can be overcome via simple chemical modifications of polymer networks to form chemically crosslinked hydrogels with significant mechanical properties and a controlled degradation rate. Additionally, the incorporation of various types of nanoparticles and polymer networks into carrageenan hydrogels has resulted in the formation of hybrid platforms with significant mechanical, chemical and biological properties, making them suitable biomaterials for drug delivery (DD), tissue engineering (TE), and wound healing applications. Herein, we aim to overview the recent advances in various chemical modification approaches and hybrid carrageenan-based platforms for tissue engineering and drug delivery applications.
|
|
| 4. |
- Tavakoli, Shima, et al.
(författare)
-
Fine-tuning Dynamic Cross-linking for Enhanced 3D Bioprinting of Hyaluronic Acid Hydrogels
- 2024
-
Ingår i: Advanced Functional Materials. - : Wiley-VCH Verlagsgesellschaft. - 1616-301X .- 1616-3028. ; 34:4
-
Tidskriftsartikel (refereegranskat)abstract
- 3D bioprinting of stem cells shows promise for medical applications, but the development of an efficient bioink remains a challenge. Recently, the emergence of dynamically cross-linked hydrogels has advanced this field to obtain self-healing materials. However, more advanced bioinks are needed that display optimum gelling kinetics, viscoelasticity, shear-thinning property, structural fidelity, and hold the printed structures sufficiently long enough that allow maturation of the new tissue. Here, a novel extracellular matrix-based bioink for human mesenchymal stem cells (hMSCs) is presented. Hyaluronic acid (HA) is modified with cysteine and aldehyde functional groups, creating hydrogels with dual cross-linking of disulfide and thiazolidine products. The investigation demonstrates that this cross-linking significantly improves hydrogel stability and biological properties. The bioink exhibits fast gelation kinetics, shear-thinning, shape-maintaining properties, high cell survival after printing with >2-fold increase in stemness marker (OCT3/4 and NANOG), and supports cell proliferation and migration. Disulfide cross-linking contributes to self-healing and cell migration, while thiazolidine cross-linking reduces gelation time, enhances long-term stability, and supports cell proliferation. Overall, the HA-based bioink fulfills the requirements for successful 3D printing of stem cells, providing a promising solution for cell therapy and regenerative medicine.
|
|
