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Skeptics of Programme for International Student Assessment (PISA) and Trend for International Math and Science Study (TIMSS) argue that while US elementary and high school students are behind their peers in other nations, the US workforce is still excellent because of the high quality post-secondary educational institutions in the US. However, the Programme for the International Assessment of Adult Competencies (PIAAC) indicates that US adults are in fact far behind their international peers in literacy, numeracy, and technology-based problem solving. Through the use of data mining, this study explored the possible association between PIAAC scores and several constructs. Since the US, Canada, and New Zealand were considered culturally similar nations, according to cluster analysis, patterns between PIAAC scores and selected constructs were analyzed by a variety of big data analytical methods, including cluster analysis, bootstrap forest, boosted tree, and data visualization. Given that PIAAC used multiple computerized adaptive testing, the consequential plausible values were randomly selected when the ensemble approach was used. Additionally, model comparison was utilized to decide between bagging and boosting in order to select the optimal model for each sample. In these samples, cultural engagement, readiness to learn, and social trust, respectively emerged as strong predictors for learning outcomes as they were assessed by PIAAC.

Purpose: Advances in the design and manufacturing of novel synthetic bioactive scaffolds as bone substitute in bone reconstruction are at the forefront of orthopedic study due to their excellent biological performances. However, fabricating bioactive scaffolds with similar osteogenic and mechanical properties of a natural bone still remains a challenge. Our aim was to produce functional bioactive scaffolds with biologically interactive ions, microstructure for cell proliferation and a suitable biodegradation rate in critical-size bone defect. Methods: A homogenous strontium-doped calcium silicate (Sr-CaSi) bioactive granule with interconnected porous network was fabricated. Critical-size bone defect (Ø ~6.5 × 8.5 mm) was created at the distal femur of New Zealand rabbit and the animals were divided into two groups (blank group and implanted/Sr-CaSi group). The blank had no granules while the implanted group was grafted with Sr-CaSi granules at the defect. Bone repair was assed using investigations of micro-CT, 3D argumentation and histological evaluations. Results: The Sr-CaSi group had complete bone healing and reconstruction. The granule showed physiochemical tolerance and was able to biodegrade enhancing the formation of new bone matrix and remodeling. However, the blank group had limited proliferation and osteogenic differentiation of new bone tissue, hence there was retarded ingrowth of new bone tissues. Conclusion: The Sr-CaSi group saw excellent bone mineralization due to biostimulation effect of the bioceramic granules. The extensive stimulation and osteogenic factors in bone healing by the novel Sr-CaSi shows it is indispensable in bone tissue engineering and regenerative medicine. [ABSTRACT FROM AUTHOR]

Abstract: Flexible electronics have enabled catheter-based intravascular sensing. However, real-time interrogation of unstable plaque remains an unmet clinical challenge. Here, we demonstrate the feasibility of stretchable electrochemical impedance spectroscopy (EIS) sensors for endoluminal investigations in New Zealand White (NZW) rabbits on diet-induced hyperlipidemia. A parylene C (PAC)-based EIS sensor mounted on the surface of an inflatable silicone balloon affixed to the tip of an interrogating catheter was deployed (1) on the explants of NZW rabbit aorta for detection of lipid-rich atherosclerotic lesions, and (2) on live animals for demonstration of balloon inflation and EIS measurements. An input peak-to-peak AC voltage of 10mV and sweeping-frequency from 300kHz to 100Hz were delivered to the endoluminal sites. Balloon inflation allowed EIS sensors to be in contact with endoluminal surface. In the oxidized low-density-lipoprotein (oxLDL)-rich lesions from explants of fat-fed rabbits, impedance magnitude increased significantly by 1.5-fold across the entire frequency band, and phase shifted ~5° at frequencies below 10kHz. In the lesion-free sites of the normal diet-fed rabbits, impedance magnitude increased by 1.2-fold and phase shifted ~5° at frequencies above 30kHz. Thus, we demonstrate the feasibility of stretchable intravascular EIS sensors for identification of lipid rich lesions, with a translational implication for detecting unstable lesions. [Copyright &y& Elsevier]