Immunoregulatory Potential of Exosomes Derived from Cancer Stem Cells.

Head and neck squamous cell carcinomas (HNSCCs) are malignancies that originate in the mucosal lining of the upper aerodigestive tract. Despite advances in therapeutic interventions, survival rates among HNSCC patients have remained static for years. Cancer stem cells (CSCs) are tumor-initiating cells that are highly resistant to treatment, and are hypothesized to contribute to a significant fraction of tumor recurrences. Consequently, further investigations of how CSCs mediate recurrence may provide insights into novel druggable targets. A key element of recurrence involves the tumor's ability to evade immunosurveillance. Recent published reports suggest that CSCs possess immunosuppressive properties, however, the underlying mechanism have yet to be fully elucidated. To date, most groups have focused on the role of CSC-derived secretory proteins, such as cytokines and growth factors. Here, we review the established immunoregulatory role of exosomes derived from mixed tumor cell populations, and propose further study of CSC-derived exosomes may be warranted. Such studies may yield novel insights into new druggable targets, or lay the foundation for future exosome-based diagnostics

Beta Irradiation of a Geometrically Metastable Superconducting Strip Detector with a Magnetic Flux Penetration Read-Out

Geometrical metastability, observed in superconducting type I tin flat strips, has been previously proposed as a principle for particle detection. The energy deposition of an incoming beta-particle induces the rupture of the metastability and consequently the penetration of multiquantum flux tubes into a superconducting tin strip. We present here the first absorption spectra from two beta sources, which demonstrate the linearity and energy-resolution of these detectors (presented at the 6th International Workshop on Low Temperature Detectors for Dark Matter and Neutrinos (LTD-6), Interlaken, Switzerland, Sept. 1995)Comment: Compressed PostScript (filename.ps.Z), 8 pages, 2 figure

S-35 Beta Irradiation of a Tin Strip in a State of Superconducting Geometrical Metastability

We report the first energy loss spectrum obtained with a geometrically metastable type I superconducting tin strip irradiated by the beta-emission of S-35. (Nucl. Instr. Meth. A, in press)Comment: Compressed PostScript (filename.ps.Z), 9 pages, 2 figure

Elective Modernism and the Politics of (Bio) Ethical Expertise

In this essay I consider whether the political perspective of third wave science studies – ‘elective modernism’ – offers a suitable framework for understanding the policy-making contributions that (bio)ethical experts might make. The question arises as a consequence of the fact that I have taken inspiration from the third wave in order to develop an account of (bio)ethical expertise. I offer a précis of this work and a brief summary of elective modernism before considering their relation. The view I set out suggests that elective modernism is a political philosophy and that although its use in relation to the use of scientific expertise in political and policy-making process has implications for the role of (bio)ethical expertise it does not, in the final analysis, provide an account that is appropriate for this latter form of specialist expertise. Nevertheless, it is an informative perspective, and one that can help us make sense of the political uses of (bio)ethical expertise

On POD analysis of PIV measurements applied to mixing in a stirred vessel with a shear thinning fluid

P.O.D. technique is applied to 2D P.I.V. data in the field of hydrodynamics in a mixing tank with a Rushton turbine and a shear thinning fluid. Classical eigen-value spectrum is presented and phase portrait of P.O.D. coefficients are plotted and analyzed in terms of trailing vortices. A spectrum of dissipation rate of kinetic energy is introduced and discussed. Length scales associated to each P.O.D. modes are proposed

Effect of teeth micro-geometrical form modification on contact kinematics and efficiency of high performance transmissions

Light weight, compactness and efficiency are key objectives in high performance vehicular transmission systems, which are subject to large variations in torque and power. Pitch line velocities of up to 52 m/s and teeth pair contact pressures of up to 3 GPa are routinely encountered under race conditions. Contact patch asymmetry due to angular misalignments between input and output shafts leads to the generation of high edge stress discontinuities on gear flanks, inducing fatigue spalling which affects system durability. Crowning is widely used as a palliative measure to mitigate these undesired effects. These problems can be further exacerbated by contact footprint truncation. The paper presents a new approach to modelling the kinematics and contact micro-geometry of meshing conjunctions of involute spur gears with profile and lead modifications. A time-efficient analytical method is presented to accurately determine the contact footprint and kinematics, leading to the solution of highly loaded non-Newtonian mixed thermo-elastohydrodynamic contact under the extreme prevalent conditions of high performance vehicular transmissions. The effect of tooth form modification on contact footprint truncation, contact kinematics and generated frictional power loss is investigated. This approach has not hitherto been reported in literature

Who are these youths? Language in the service of policy

In the 1990s policy relating to children and young people who offend developed as a result of the interplay of political imperatives and populist demands. The ‘responsibilisation’ of young offenders and the ‘no excuses’ culture of youth justice have been ‘marketed’ through a discourse which evidences linguistic changes. This article focuses on one particular area of policy change, that relating to the prosecutorial decision, to show how particular images of children were both reflected and constructed through a changing selection of words to describe the non-adult suspect and offender. In such minutiae of discourse can be found not only the signifiers of public attitudinal and policy change but also the means by which undesirable policy developments can be challenged

Crack-Like Processes Governing the Onset of Frictional Slip

We perform real-time measurements of the net contact area between two blocks of like material at the onset of frictional slip. We show that the process of interface detachment, which immediately precedes the inception of frictional sliding, is governed by three different types of detachment fronts. These crack-like detachment fronts differ by both their propagation velocities and by the amount of net contact surface reduction caused by their passage. The most rapid fronts propagate at intersonic velocities but generate a negligible reduction in contact area across the interface. Sub-Rayleigh fronts are crack-like modes which propagate at velocities up to the Rayleigh wave speed, VR, and give rise to an approximate 10% reduction in net contact area. The most efficient contact area reduction (~20%) is precipitated by the passage of slow detachment fronts. These fronts propagate at anomalously slow velocities, which are over an order of magnitude lower than VR yet orders of magnitude higher than other characteristic velocity scales such as either slip or loading velocities. Slow fronts are generated, in conjunction with intersonic fronts, by the sudden arrest of sub-Rayleigh fronts. No overall sliding of the interface occurs until either of the slower two fronts traverses the entire interface, and motion at the leading edge of the interface is initiated. Slip at the trailing edge of the interface accompanies the motion of both the slow and sub-Rayleigh fronts. We might expect these modes to be important in both fault nucleation and earthquake dynamics.Comment: 19 page, 5 figures, to appear in International Journal of Fractur

Dissipation of vibration in rough contact

The relationship which links the normal vibration occurring during the sliding of rough surfaces and the nominal contact area is investigated. Two regimes are found. In the first one, the vibrational level does not depend on the contact area, while in the second one, it is propor- tional to the contact area. A theoretical model is proposed. It is based on the assumption that the vibrational level results from a competition between two processes of vibration damping, the internal damping of the material and the contact damping occurring at the interface