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Treatment of injuries to bone structure represents a significant economic burden for health care institutions and systems worldwide. The development of tissue engineering scaffolds has expanded to include the incorporation of nanotechnology platforms such as liposomes for the efficient delivery of chemotherapeutic agents. Pyrroloquinoline quinone (PQQ) is a naturally occurring quinone with antioxidant and tissue regenerative properties. In this study, the liposome-based encapsulation of PQQ was achieved by studying the effect of different downsizing methods and lipid compositions. Liposomal sonication produced stable vesicles of sizes

Biodegradable materials such as WE43 magnesium are of great interest for bone tissue engineering applications. This research paper presents a novel manufacturing methodology (i.e., Joining Stacking based Laser Micro-Spot Welding (JS-LMSW)) for produce tubular WE43 Magnesium scaffolds. The proposed methodology consists of laser-cut tailored geometries joined and stacked using laser micro-spot welding to form a porous structure (scaffold). The relationship between microstructure and mechanical properties of the manufactured WE43 magnesium scaffolds is summarized in this paper. Additionally, the manufactured scaffolds were dimensionally and morphologically characterized, and the obtained results are close to the designed values (relative errors of ∼ 1.04%, 0.93%, 0.83%, and 1.53% for length, width, height, and interconnected porosity, respectively). Compressive testing was conducted on the scaffolds for axial and transversal loading conditions and, micro-hardness was evaluated in the micro spot welds. The obtained results indicated that the developed WE43 magnesium scaffold features bone-like mechanical properties. The elastic modulus range of cancellous bone is between 0.01 and 0.90 GPa compared to WE43 magnesium scaffold́s elastic modulus between 0.07 and 0.41 GPa for transversal and axial conditions, respectively. Hardness results showed values between 74 HV and 80 HV in the fusion zone and heat-affected zone, respectively. This novel methodology opens a new path for the construction of complex geometries such as scaffolds.

Objective: Summarize the effects of interventions designed to promote physical activity during elementary school recess in children between 5 and 10 years old. Effective school interventions for children can promote physical activity and healthy behaviors. Methods: PubMed, Scopus, Bireme, SciELO, Web of Science, PsychINFO, Proquest, Physical Education Index, Sports Discus, and Eric databases were included in the data search. Original intervention articles on physical activity that used regression methods, published between 2000 and 2019 in English, Portuguese and Spanish were analyzed. Analyses were performed in 2019. Outcomes were organized according to the direction of the association by independent variables. Ten articles were considered eligible for data extraction and evaluation. Results: Several strategies were used including playground markings, demarcation of physical activities zones, group activities, availability of sports equipment and facilities. Most of the studies were conducted in the United States. Recess periods ranged from 20–94 min per day and intervention time ranged from 6 weeks to 2 years. Recess duration and intervention effects were positively associated with physical activity. Gender (girls) and age (oldest) were negatively associated with physical activity during recess. Conclusions: Interventions based on modifications of school environment such as playground markings demarcation of physical activities zones, group activities, availability of sports equipment and facilities are cheap and cost-effective for increasing physical activity in school recess.