Do managed clinical networks improve quality of diabetes care? : Evidence from a retrospective mixed methods evaluation

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Design and development of a peristaltic pump for constant flow applications

In wide-ranging areas, including hydraulics, biomedical, automotive, and aerospace, there is often a need to move a fluid with a constant flow rate. This is difficult to achieve with any type of pump and usually other elements are inserted to regularize the output. This study focused on the peristaltic pump because there are few studies on it and it has some interesting features, such as extreme simplicity, a small number of components, and the extreme compactness of the whole system. The first part of this study is focused on analyzing the classical geometry of the peristaltic pump to understand the origin of the discontinuity in the flow rate; the second part proposes a new geometry that mitigates the flow irregularity by more than 200%. In this way, it is possible to use it in all the sectors where a constant flow rate is required but where insulation between the fluid and the machine is required. Together with the flow study, an analysis of how the main geometric parameters affect the operation of the pump is provided, complete with explanatory graphs and tables. A prototype made through additive manufacturing technologies is also proposed

Interfacing Sca-1pos Mesenchymal Stem Cells with Biocompatible Scaffolds with Different Chemical Composition and Geometry

An immortalized murine mesenchymal stem cell line (mTERT-MSC) enriched for Linneg/Sca-1pos fraction has been obtained through the transfection of MSC with murine TERT and single-cell isolation. Such cell line maintained the typical MSC self-renewal capacity and continuously expressed MSC phenotype. Moreover, mTERT-MSC retained the functional features of freshly isolated MSC in culture without evidence of senescence or spontaneous differentiation events. Thus, mTERT-MSC have been cultured onto PLA films, 30 and 100 μm PLA microbeads, and onto unpressed and pressed HYAFF-11 scaffolds. While the cells adhered preserving their morphology on PLA films, clusters of mTERT-MSC were detected on PLA beads and unpressed fibrous scaffolds. Finally, mTERT-MSC were not able to colonize the inner layers of pressed HYAFF-11. Nevertheless, such cell line displayed the ability to preserve Sca-1 expression and to retain multilineage potential when appropriately stimulated on all the scaffolds tested

Multiscale three-dimensional scaffolds for soft tissue engineering via multimodal electrospinning

A novel (scalable) electrospinning process was developed to fabricate bio-inspired multiscale three-dimensional scaffolds endowed with a controlled multimodal distribution of fiber diameters and geared towards soft tissue engineering. The resulting materials finely mingle nano- and microscale fibers together, rather than simply juxtaposing them, as is commonly found in the literature. A detailed proof of concept study was conducted on a simpler bimodal poly(ε-caprolactone) (PCL) scaffold with modes of fiber distribution at 600 nm and 3.3 μm. Three conventional unimodal scaffolds with mean diameters of 300 nm and 2.6 and 5.2 μm, respectively, were used as controls to evaluate the new materials. Characterization of the microstructure (i.e. porosity, fiber distribution and pore structure) and mechanical properties (i.e. stiffness, strength and failure mode) indicated that the multimodal scaffold had superior mechanical properties (Young's modulus ∼40 MPa and strength ∼1 MPa) in comparison with the controls, despite the large porosity (∼90% on average). A biological assessment was conducted with bone marrow stromal cell type (mesenchymal stem cells, mTERT-MSCs). While the new material compared favorably with the controls with respect to cell viability (on the outer surface), it outperformed them in terms of cell colonization within the scaffold. The latter result, which could neither be practically achieved in the controls nor expected based on current models of pore size distribution, demonstrated the greater openness of the pore structure of the bimodal material, which remarkably did not come at the expense of its mechanical properties. Furthermore, nanofibers were seen to form a nanoweb bridging across neighboring microfibers, which boosted cell motility and survival. Lastly, standard adipogenic and osteogenic differentiation tests served to demonstrate that the new scaffold did not hinder the multilineage potential of stem cells. © 2009 Acta Materialia Inc

Uav Photogrammetry: Block Triangulation Comparisons

UAVs systems represent a flexible technology able to collect a big amount of high resolution information, both for metric and interpretation uses. In the frame of experimental tests carried out at Dept. ICA of Politecnico di Milano to validate vector-sensor systems and to assess metric accuracies of images acquired by UAVs, a block of photos taken by a fixed wing system is triangulated with several software. The test field is a rural area included in an Italian Park ("Parco Adda Nord"), useful to study flight and imagery performances on buildings, roads, cultivated and uncultivated vegetation. The UAV SenseFly, equipped with a camera Canon Ixus 220HS, flew autonomously over the area at a height of 130 m yielding a block of 49 images divided in 5 strips. Sixteen pre-signalized Ground Control Points, surveyed in the area through GPS (NRTK survey), allowed the referencing of the block and accuracy analyses. Approximate values for exterior orientation parameters (positions and attitudes) were recorded by the flight control system. The block was processed with several software: Erdas-LPS, EyeDEA (Univ. of Parma), Agisoft Photoscan, Pix4UAV, in assisted or automatic way. Results comparisons are given in terms of differences among digital surface models, differences in orientation parameters and accuracies, when available. Moreover, image and ground point coordinates obtained by the various software were independently used as initial values in a comparative adjustment made by scientific in-house software, which can apply constraints to evaluate the effectiveness of different methods of point extraction and accuracies on ground check points

Locally linear embedding-based prediction for 3D holoscopic image coding using HEVC

Holoscopic imaging is a prospective acquisition and display solution for providing true 3D content and fatigue-free 3D visualization. However, efficient coding schemes for this particular type of content are needed to enable proper storage and delivery of the large amount of data involved in these systems. Therefore, this paper proposes an alternative HEVC-based coding scheme for efficient representation of holoscopic images. In this scheme, some directional intra prediction modes of the HEVC are replaced by a more efficient prediction framework based on locally linear embedding techniques. Experimental results show the advantage of the proposed prediction for 3D holoscopic image coding, compared to the reference HEVC standard as well as previously presented approaches in this field.info:eu-repo/semantics/submittedVersio