First normal stress difference and crystallization in a dense sheared granular fluid

The first normal stress difference (${\mathcal N}_1$) and the microstructure in a dense sheared granular fluid of smooth inelastic hard-disks are probed using event-driven simulations. While the anisotropy in the second moment of fluctuation velocity, which is a Burnett-order effect, is known to be the progenitor of normal stress differences in {\it dilute} granular fluids, we show here that the collisional anisotropies are responsible for the normal stress behaviour in the {\it dense} limit. As in the elastic hard-sphere fluids, ${\mathcal N}_1$ remains {\it positive} (if the stress is defined in the {\it compressive} sense) for dilute and moderately dense flows, but becomes {\it negative} above a critical density, depending on the restitution coefficient. This sign-reversal of ${\mathcal N}_1$ occurs due to the {\it microstructural} reorganization of the particles, which can be correlated with a preferred value of the {\it average} collision angle $\theta_{av}=\pi/4 \pm \pi/2$ in the direction opposing the shear. We also report on the shear-induced {\it crystal}-formation, signalling the onset of fluid-solid coexistence in dense granular fluids. Different approaches to take into account the normal stress differences are discussed in the framework of the relaxation-type rheological models.Comment: 21 pages, 13 figure

Subclone eradication analysis identifies targets for enhanced cancer therapy and reveals L1 retrotransposition as a dynamic source of cancer heterogeneity

Treatment-eradicated cancer subclones have been reported in leukemia and have recently been detected in solid tumors. Here we introduce Differential Subclone Eradication and Resistance Analysis (DSER), a method developed to identify molecular targets for improved therapy by direct comparison of genomic features of eradicated and resistant subclones in pre- and post-treatment samples from a patient with BRCA2-deficient metastatic prostate cancer. FANCI and EYA4 were identified as candidate DNA repair-related targets for converting subclones from resistant to eradicable, and RNAi-mediated depletion of FANCI confirmed it as a potential target. The EYA4 alteration was associated with adjacent L1 transposon insertion during cancer evolution upon treatment, raising questions surrounding the role of therapy in L1 activation. Both carboplatin and enzalutamide turned on L1 transposon machinery in LNCaP and VCaP but not in PC-3 and 22Rv1 prostate cancer cell lines. L1 activation in LNCaP and VCaP was inhibited by the antiretroviral drug azidothymidine. L1 activation was also detected post-castration in LuCaP 77 and LuCaP 105 xenograft models and post-chemotherapy in previously published time-series transcriptomic data from SCC25 head and neck cancer cells. In conclusion DSER provides an informative intermediate step toward effective precision cancer medicine and should be tested in future studies, especially those including dramatic but temporary metastatic tumor regression. L1 transposon activation may be a modifiable source of cancer genomic heterogeneity, suggesting the potential of leveraging newly discovered triggers and blockers of L1 activity to overcome therapy resistance

Pharmacological prevention of type 2 diabetes.

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Shur algebras, combinatorics, and cohomology

SIGLEAvailable from British Library Document Supply Centre- DSC:D96482 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Revising the paradigm of control in repetitive production

SIGLEAvailable from British Library Document Supply Centre- DSC:DX180381 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Conformance Checking of Dynamic Access Control Policies

The capture, deployment and enforcement of appropriate access control policies are crucial aspects of many modern software-based systems. Previously, there has been a significant amount of research undertaken with respect to the formal modelling and analysis of access control policies; however, only a limited proportion of this work has been concerned with dynamic policies. In this paper we explore techniques for the modelling, analysis and subsequent deployment of such policies - which may rely on external data. We use the Alloy modelling language to describe constraints on policies and external data; utilising these constraints, we test static instances constructed from the current state of the external data. We present Gauge, a constraint checker for static instances that has been developed to be complementary to Alloy, and show how it is possible to test systems of much greater complexity via Gauge than can typically be handled by a model finder. © 2011 Springer-Verlag