An investigation into the effects of ion tracks on α-quartz

The passage of a swift heavy ion through a material can cause columnar, amorphous nano-structures known as ion tracks. Swift heavy ions are present in a number of applications ranging from nuclear reactors to nuclear waste storage and onboard spacecraft. The study of ion tracks has been ongoing since the late 1950s and has led to several technological advancements. In fact, ion beams have been used to enhance material properties and aid in the production of electrical components. Ion beams, and their resultant ion tracks, can therefore be seen as a method to purposefully alter material properties such as thermal diffusivity. One method through which ion tracks can alter material properties is through the alteration of phonon transport. It is expected that phonons are spatially confined between ion tracks. In this study, Z- and Y-cut α-quartz single crystalline samples were irradiated with 20 MeV nickel 6+ ions. These crystals were irradiated to nominal fluence values of 1.0x109, 1.0x1010, and 1.0x1012 ions cm-2. The crystals were irradiated with varying fluence values in order to understand how the spacing of ion tracks affects phonon transport. An Inelastic Thermal Spike model was also developed to model the track radii. The Thermal Spike model allows for the effects of track size to also be taken in to account. In addition, Raman spectroscopy was performed for each fluence value. The effects of ion tracks on phonon confinement were understood by examining how the peak parameters changed with increasing fluence and comparing the parameters to the phonon dispersion relations for α-quartz --Abstract, page iii

DNC / CRONOS Deployment 703040

KCP tested a classified DNC / CRONOS as a pilot project in FY06 in the Reservoir Machining area. The pilot proved as a successful way to distribute classified NC Programs to machines that run both classified and unclassified programs securely. This also allows for elimination of CREM for machines which had to swap out classified and unclassified hard drives previously. This project’s purpose is to rollout this technology to the remaining machining areas, predominately Department B, Department C and Department A. Associated with this activity is the modification of business practices in the Tool Room / Model Shop areas and to address licensing issues for MASTERCAM to incorporate DNC CRONOS

Self-Cleaning Surfaces Realized by Biologically Sized Magnetic Artificial Cilia

Magnetic artificial cilia (MAC) are small actuators inspired by biological cilia found in nature. In microfluidic chips, MAC can generate flow and remove microparticles, with applications in anti-fouling. However, the MAC used for anti-fouling in the current literature has dimensions of several hundred micrometers in length, which limits the application to relatively large length scales. Here, biologically-sized magnetic artificial cilia (b-MAC) which are only 45 micrometers long and that are randomly distributed on the surface, are used to remove microparticles. It is shown that microparticles with sizes ranging from 5 to 40 µm can be removed efficiently and the final cleanness ranges from 69% to 100%, with the highest cleanness for the highest actuation frequency applied (40 Hz). The lowest cleanness is obtained for microparticles with a size equal to the average pitch between the b-MAC. The randomness in cilia distribution appears to have a positive effect on cleanliness, compared with the authors’ earlier work using a regular cilia array. The demonstrated self-cleaning by the b-MAC constitutes an essential step toward efficient self-cleaning surfaces for real-life application in miniaturized microfluidic devices, such as lab-on-a-chip or organ-on-a-chip devices, as well as for preventing fouling of submerged surfaces such as marine sensors.</p

Self-Cleaning Surfaces Realized by Biologically Sized Magnetic Artificial Cilia

Magnetic artificial cilia (MAC) are small actuators inspired by biological cilia found in nature. In microfluidic chips, MAC can generate flow and remove microparticles, with applications in anti-fouling. However, the MAC used for anti-fouling in the current literature has dimensions of several hundred micrometers in length, which limits the application to relatively large length scales. Here, biologically-sized magnetic artificial cilia (b-MAC) which are only 45 micrometers long and that are randomly distributed on the surface, are used to remove microparticles. It is shown that microparticles with sizes ranging from 5 to 40 µm can be removed efficiently and the final cleanness ranges from 69% to 100%, with the highest cleanness for the highest actuation frequency applied (40 Hz). The lowest cleanness is obtained for microparticles with a size equal to the average pitch between the b-MAC. The randomness in cilia distribution appears to have a positive effect on cleanliness, compared with the authors’ earlier work using a regular cilia array. The demonstrated self-cleaning by the b-MAC constitutes an essential step toward efficient self-cleaning surfaces for real-life application in miniaturized microfluidic devices, such as lab-on-a-chip or organ-on-a-chip devices, as well as for preventing fouling of submerged surfaces such as marine sensors.</p

CD69 is a TGF-β/1α,25-dihydroxyvitamin D3 target gene in monocytes

CD69 is a transmembrane lectin that can be expressed on most hematopoietic cells. In monocytes, it has been functionally linked to the 5-lipoxygenase pathway in which the leukotrienes, a class of highly potent inflammatory mediators, are produced. However, regarding CD69 gene expression and its regulatory mechanisms in monocytes, only scarce data are available. Here, we report that CD69 mRNA expression, analogous to that of 5-lipoxygenase, is induced by the physiologic stimuli transforming growth factor-β (TGF-β) and 1α,25-dihydroxyvitamin D3 (1α,25(OH)2D3) in monocytic cells. Comparison with T- and B-cell lines showed that the effect was specific for monocytes. CD69 expression levels were increased in a concentration-dependent manner, and kinetic analysis revealed a rapid onset of mRNA expression, indicating that CD69 is a primary TGF-β/1α,25(OH)2D3 target gene. PCR analysis of different regions of the CD69 mRNA revealed that de novo transcription was initiated and proximal and distal parts were induced concomitantly. In common with 5-lipoxygenase, no activation of 0.7 kb or ~2.3 kb promoter fragments by TGF-β and 1α,25(OH)2D3 could be observed in transient reporter assays for CD69. Analysis of mRNA stability using a transcription inhibitor and a 3′UTR reporter construct showed that TGF-β and 1α,25(OH)2D3 do not influence CD69 mRNA stability. Functional knockdown of Smad3 clearly demonstrated that upregulation of CD69 mRNA, in contrast to 5-LO, depends on Smad3. Comparative studies with different inhibitors for mitogen activated protein kinases (MAPKs) revealed that MAPK signalling is involved in CD69 gene regulation, whereas 5-lipoxygenase gene expression was only partly affected. Mechanistically, we found evidence that CD69 gene upregulation depends on TAK1-mediated p38 activation. In summary, our data indicate that CD69 gene expression, conforming with 5-lipoxygenase, is regulated monocyte-specifically by the physiologic stimuli TGF-β and 1α,25(OH)2D3 on mRNA level, although different mechanisms account for the upregulation of each gene

Post-transcriptional control during chronic inflammation and cancer: a focus on AU-rich elements

A considerable number of genes that code for AU-rich mRNAs including cytokines, growth factors, transcriptional factors, and certain receptors are involved in both chronic inflammation and cancer. Overexpression of these genes is affected by aberrations or by prolonged activation of several signaling pathways. AU-rich elements (ARE) are important cis-acting short sequences in the 3′UTR that mediate recognition of an array of RNA-binding proteins and affect mRNA stability and translation. This review addresses the cellular and molecular mechanisms that are common between inflammation and cancer and that also govern ARE-mediated post-transcriptional control. The first part examines the role of the ARE-genes in inflammation and cancer and sequence characteristics of AU-rich elements. The second part addresses the common signaling pathways in inflammation and cancer that regulate the ARE-mediated pathways and how their deregulations affect ARE-gene regulation and disease outcome

Rapid Response Small Machining NNR Project 703025

This project was an effort to develop a machining area for small sized parts that is capable of delivering product with a quick response time. This entailed focusing efforts on leaning out specific work cells that would result in overall improvement to the entire machining area. This effort involved securing the most efficient available technologies for these areas. In the end, this incorporated preparing the small machining area for transformation to a new facility

Isconf: Theory, Practice, and Beyond

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