3D Printed Functional and Biological Materials on Moving Freeform Surfaces

Conventional 3D printing technologies typically rely on open‐loop, calibrate‐then‐print operation procedures. An alternative approach is adaptive 3D printing, which is a closed‐loop method that combines real‐time feedback control and direct ink writing of functional materials in order to fabricate devices on moving freeform surfaces. Here, it is demonstrated that the changes of states in the 3D printing workspace in terms of the geometries and motions of target surfaces can be perceived by an integrated robotic system aided by computer vision. A hybrid fabrication procedure combining 3D printing of electrical connects with automatic pick‐and‐placing of surface‐mounted electronic components yields functional electronic devices on a free‐moving human hand. Using this same approach, cell‐laden hydrogels are also printed on live mice, creating a model for future studies of wound‐healing diseases. This adaptive 3D printing method may lead to new forms of smart manufacturing technologies for directly printed wearable devices on the body and for advanced medical treatments.     

Limit load and failure mechanisms of soda lime glass foam

Foamed glass is widely used in the industry as an insulating material. However, its mechanical properties are not well-investigated yet. Foamed glass is produced from glass waste that causes discrepancy in mechanical properties of the final product. This paper shows a way to increase the limit of the load capacity of foamed glass, which is very fragile and sensitive to mechanical and thermal loading conditions. In this paper, three different methods of load application on cellular glass structure (rough contact, resin and flour interfaces) and their influence on failure mechanisms were investigated in detail. The results of numerical analyses, based on finite elements method and compression strength tests using the digital image correlation method, indicate that the overall strength of the material is limited by boundary effects. A careful adjustment of the interface property is the main factor to draw useful conclusions and to extend load limits of cellular glass in engineering applications.     

Fabrication of buried microfluidic channels with observation windows using femtosecond laser photoablation and parylene-C coating

We developed an advanced method for fabricating microfluidic structures comprising channels and inputs/outputs buried within a silicon wafer based on single level lithography. We etched trenches into a silicon substrate, covered these trenches with parylene-C, and selectively opened their bottoms using femtosecond laser photoablation, forming channels and inputs/outputs by isotropic etching of silicon by xenon difluoride vapors. We subsequently sealed the channels with a second parylene-C layer. Unlike in previously published works, this entire process is conducted at ambient temperature to allow for integration with complementary metal oxide semiconductor devices for smart readout electronics. We also demonstrated a method of chip cryo-cleaving with parylene presence that allows for monitoring of the process development. We also created an observation window for in situ visualization inside the opaque silicon substrate by forming a hole in the parylene layer at the silicon backside and with local silicon removal by xenon difluoride vapor etching. We verified the microfluidic chip performance by forming a segmented flow of a fluorescein solution in an oil stream. This proposed technique provides opportunities for forming simple microfluidic systems with buried channels at ambient temperature.     

A feasibility study of using CeO2 as a surrogate material during the investigation of UO2 thermal conductivity enhancement

A possible substitution of UO₂ for research purposes is the cerium dioxide (CeO₂) owing to its chemical and physical properties. Neutronic properties are different and fission is absent in the case of CeO₂; however, similarities were studied recently to have a possibility to compare the neutronic influence of secondary additives into the matrix. This paper deals with increasing the thermal conductivity of UO₂ nuclear fuel on surrogate material (CeO₂); the main focus of the research is given on the sintering behaviour of CeO₂. The incorporation of highly thermally conductive material (SiC) is the investigated concept of thermal conductivity enhancement. Conventional sintering and spark plasma sintering (SPS) were applied to compare the behaviour of CeO₂ and UO₂ reported in the literature. High temperature thermal conductivity measurements did not confirm the positive influence of SiC additive inside the CeO₂ matrix mainly due to grain boundary disruptions. Similar behaviour was also previously reported for UO₂ pellets with SiC.     

Uncertainties in determination of 131I activity in thyroid gland

The values of the iodine (131)I uptake determined from the measurements with a NaI scintillation counter might be significantly influenced by the thyroid position in the human neck. It is shown that the ratio of the counting rate in the energy peak of 364 keV to the counting rate in the Compton scattering band can be used for the determination of the effective depth of the thyroid. The uncertainties of the standard method are discussed basing on results of calibration measurements. The investigations of 95 patients with different thyroid diseases showed that the measured iodine spectrum was considerably different from the standard for about 20% of them, indicating possible high uncertainties of the standard measurements, which assume a fixed thyroid depth of 20 mm.     

Tepotinib Inhibits Several Drug Efflux Transporters and Biotransformation Enzymes: The Role in Drug-Drug Interactions and Targeting Cytostatic Resistance In Vitro and Ex Vivo

Tepotinib is a novel tyrosine kinase inhibitor recently approved for the treatment of non-small cell lung cancer (NSCLC). In this study, we evaluated the tepotinib’s potential to perpetrate pharmacokinetic drug interactions and modulate multidrug resistance (MDR). Accumulation studies showed that tepotinib potently inhibits ABCB1 and ABCG2 efflux transporters, which was confirmed by molecular docking. In addition, tepotinib inhibited several recombinant cytochrome P450 (CYP) isoforms with varying potency. In subsequent drug combination experiments, tepotinib synergistically reversed daunorubicin and mitoxantrone resistance in cells with ABCB1 and ABCG2 overexpression, respectively. Remarkably, MDR-modulatory properties were confirmed in ex vivo explants derived from NSCLC patients. Furthermore, we demonstrated that anticancer effect of tepotinib is not influenced by the presence of ABC transporters associated with MDR, although monolayer transport assays designated it as ABCB1 substrate. Finally, tested drug was observed to have negligible effect on the expression of clinically relevant drug efflux transporters and CYP enzymes. In conclusion, our findings provide complex overview on the tepotinib’s drug interaction profile and suggest a promising novel therapeutic strategy for future clinical investigations.