Time-Resolved Infrared Radiometry (Trir) for Characterization of Impact Damage in Composite Materials

A quantitative thermographie NDE technique for the characterization of impact damage in composite materials is under development along with supporting theoretical analysis. We have previously shown that the technique of time-resolved infrared radiometry (TRIR) is an effective method for quantitatively detecting coating thickness variations and for characterizing the degree of coating disbonding in terms of equivalent air gaps [1,2]. Here we extend the TRIR technique to the study of composite systems by applying the results of a multilayer analytical model [3]. Experimental results in both simple and hybrid composite systems are discussed. The depth and lateral extent of interlaminar separation in composites subjected to impact loading is presented and the use of lateral heat flow techniques to image defect structures is examined

Globalization and Health: developing the journal to advance the field

Founded in 2005, Globalization and Health was the first open access global health journal. The journal has since expanded the field, and its influence, with the number of downloaded papers rising 17-fold, to over 4 million. Its ground-breaking papers, leading authors -including a Nobel Prize winner- and an impact factor of 2.25 place it among the top global health journals in the world. To mark the ten years since the journal’s founding, we, members of the current editorial board, undertook a review of the journal’s progress over the last decade. Through the application of an inductive thematic analysis, we systematically identified themes of research published in the journal from 2005 to 2014. We identify key areas the journal has promoted and consider these in the context of an existing framework, identify current gaps in global health research and highlight areas we, as a journal, would like to see strengthened

Parallel Imaging of Thickness Variations and Disbonding of Thermal Barrier Coatings by Time-Resolved Infrared Radiometry (TRIR)

Pulsed photothermal radiometry has been shown to be a useful thermally-based nondestructive evaluation technique for various thin films and layered specimens [1,2]. In this method the time development of the surface temperature is studied for both heating and cooling, during and after the application of a step heating pulse of duration, T. In this paper, we show that the method gives quantitative information about layered materials including measurement of coating thickness and the detection and characterization of disbonding between layers. Since all times are monitored, it is not necessary to know the thickness of the coating provided the heating pulse is set longer than the thermal transit time of the coating. As a result, both coating thickness and the integrity of the coating-substrate bond can be determined simultaneously.</p

Time-Resolved Infrared Radiometry (Trir) for Characterization of Impact Damage in Composite Materials

A quantitative thermographie NDE technique for the characterization of impact damage in composite materials is under development along with supporting theoretical analysis. We have previously shown that the technique of time-resolved infrared radiometry (TRIR) is an effective method for quantitatively detecting coating thickness variations and for characterizing the degree of coating disbonding in terms of equivalent air gaps [1,2]. Here we extend the TRIR technique to the study of composite systems by applying the results of a multilayer analytical model [3]. Experimental results in both simple and hybrid composite systems are discussed. The depth and lateral extent of interlaminar separation in composites subjected to impact loading is presented and the use of lateral heat flow techniques to image defect structures is examined.</p

Determination of Degree of Thermal Barrier Coating Disbonding by Time-Resolved Infrared Radiometry (TRIR)

We have previously described the time-resolved infrared radiometry (TRIR) technique and demonstrated how both measurement of coating thickness and detection of coating disbonding can be made within the same measurement [1]. We have also reported indications of the sensitivity of the TRIR technique to differing degrees of coating disbonding [2]. In the present work we examine this question in detail and compare TRIR experimental results with both an analytical multilayer theory and a destructive analysis of the coating-substrate interface. While the material system studied in this work is a zirconia thermal barrier coating on a superalloy substrate, the methodology and analytical basis of the technique are applicable to a wide variety of materials and components including printed circuit boards and composite materials. The capability of the TRIR technique for characterization of these specific systems will depend on details of the thermal properties and layer thickness in these specimens.</p

Vitamin B5 supports MYC oncogenic metabolism and tumor progression in breast cancer.

Tumors are intrinsically heterogeneous and it is well established that this directs their evolution, hinders their classification and frustrates therapy1-3. Consequently, spatially resolved omics-level analyses are gaining traction4-9. Despite considerable therapeutic interest, tumor metabolism has been lagging behind this development and there is a paucity of data regarding its spatial organization. To address this shortcoming, we set out to study the local metabolic effects of the oncogene c-MYC, a pleiotropic transcription factor that accumulates with tumor progression and influences metabolism10,11. Through correlative mass spectrometry imaging, we show that pantothenic acid (vitamin B5) associates with MYC-high areas within both human and murine mammary tumors, where its conversion to coenzyme A fuels Krebs cycle activity. Mechanistically, we show that this is accomplished by MYC-mediated upregulation of its multivitamin transporter SLC5A6. Notably, we show that SLC5A6 over-expression alone can induce increased cell growth and a shift toward biosynthesis, whereas conversely, dietary restriction of pantothenic acid leads to a reversal of many MYC-mediated metabolic changes and results in hampered tumor growth. Our work thus establishes the availability of vitamins and cofactors as a potential bottleneck in tumor progression, which can be exploited therapeutically. Overall, we show that a spatial understanding of local metabolism facilitates the identification of clinically relevant, tractable metabolic targets