3D printed lattice metal structures for enhanced heat transfer in latent heat storage systems

The low thermal conductivity of Phase Change Materials (PCMs), e.g., paraffin waxes, is one of the main drawbacks of latent heat storage, especially when fast charging and discharging cycles are required. The introduction of highly conductive fillers in the PCM matrix may be an effective solution; however, it is difficult to grant their stable and homogeneous dispersion, which therefore limits the resulting enhancement of the overall thermal conductivity. Metal 3D printing or additive manufacturing, instead, allows to manufacture complex geometries with precise patterns, therefore allowing the design of optimal paths for heat conduction within the PCM. In this work, a device-scale latent heat storage system operating at medium temperatures (similar to 90 celcius) was manufactured and characterized. Its innovative design relies on a 3D Cartesian metal lattice, fabricated via laser powder bed fusion, to achieve higher specific power densities. Numerical and experimental tests demonstrated remarkable specific power (approximately 714 +/- 17 W kg-1 and 1310 +/- 48 W kg-1 during heat charge and discharge, respectively). Moreover, the device performance remained stable over multiple charging and discharging cycles. Finally, simulation results were used to infer general design guidelines to further enhance the device performance. This work aims at promoting the use of metal additive manufacturing to design efficient and responsive thermal energy storage units for medium-sized applications, such as in the automotive sector (e.g. speed up of the engine warm up or as an auxiliary for other enhanced thermal management strategies)

The effectiveness of computerized clinical guidelines in the process of care: a systematic review

<p>Abstract</p> <p>Background</p> <p>Clinical practice guidelines have been developed aiming to improve the quality of care. The implementation of the computerized clinical guidelines (CCG) has been supported by the development of computerized clinical decision support systems.</p> <p>This systematic review assesses the impact of CCG on the process of care compared with non-computerized clinical guidelines.</p> <p>Methods</p> <p>Specific features of CCG were studied through an extensive search of scientific literature, querying electronic databases: Pubmed/Medline, Embase and Cochrane Controlled Trials Register. A multivariable logistic regression was carried out to evaluate the association of CCG's features with positive effect on the process of care.</p> <p>Results</p> <p>Forty-five articles were selected. The logistic model showed that Automatic provision of recommendation in electronic version as part of clinician workflow (Odds Ratio [OR]= 17.5; 95% confidence interval [CI]: 1.6-193.7) and Publication Year (OR = 6.7; 95%CI: 1.3-34.3) were statistically significant predictors.</p> <p>Conclusions</p> <p>From the research that has been carried out, we can conclude that after implementation of CCG significant improvements in process of care are shown. Our findings also suggest clinicians, managers and other health care decision makers which features of CCG might improve the structure of computerized system.</p

Stereoselective synthesis and conformational analysis of unnatural tetrapeptides. Part 2

Stereoselective synthesis of unnatural tetrapeptides containing two L-valine units and two unnatural alpha-amino acids (ornithine and modified aspartic acid), has been accomplished starting from a L-valine derived chiral synthon. Structural investigations of these non-proteinogenic peptides have been carried out on the acetamido derivatives using 1H-NMR, IR spectroscopic techniques and a conformational analysis based on molecular dynamics (MD) and cluster analysis