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BackgroundIncreased success in the treatment of hematological cancers contributed to the increase of 5-year survival for most adolescent and young adults (AYAs) with these tumours. However, as 5-year survival increased, it became clear that AYA long-term survivors were at increased risk for severe late effects. Moreover, limited information on long-term cancer impact is available for AYAs, since most studies focused on children and adolescents. We aimed to assess various long-term outcomes on AYA survivors of hematological cancers.MethodsWe selected patients diagnosed with a first primary hematological cancer between 1997 and 2006, in the Italian nationwide population-based cohort of AYA cancer survivors (i.e. alive at least 5 years after cancer diagnosis). Long-term outcomes of interest were: second malignant neoplasms (SMNs), hospitalizations and overall mortality. We calculated standardized incidence ratios (SIRs), standardized hospitalization rate ratios (SHRs) and standardized mortality rate ratios (SMRs). To study morbidity patterns over time, we modeled observed incidence rates by fitting flexible parametric models for nonlinear patterns and we used linear regression for linear patterns.ResultsThe study cohort included 5,042 AYA hematological cancer survivors of which 1,237 and 3,805 had a leukaemia and lymphoma diagnosis, respectively. AYA survivors were at substantially increased risk for SMN (SIR=2.1; 95%CI=1.7; 2.6), hospitalisation (SHR=1.5; 95%CI=1.5; 1.6), and mortality (SMR=1.4; 95%CI=1.2; 1.6) with differences between leukaemia and lymphoma survivors. The highest excess risks of hospitalisations were for infectious diseases, respiratory diseases, and diseases of blood and blood-forming organs. The morbidity pattern differs over time by morbidity type.ConclusionsOur results support the need for strict follow-up plans for survivors, and call for further study to better personalised follow-up plans for AYA cancer survivors.

Mu2e at Fermilab will search for charged lepton flavor violation via the coherent conversion process mu- N --> e- N with a sensitivity approximately four orders of magnitude better than the current world's best limits for this process. The experiment's sensitivity offers discovery potential over a wide array of new physics models and probes mass scales well beyond the reach of the LHC. We describe herein the conceptual design of the proposed Mu2e experiment. This document was created in partial fulfillment of the requirements necessary to obtain DOE CD-1 approval, which was granted July 11, 2012., 562 pages, 339 figures

We propose a phase-field model for ductile fracture in a single crystal within the kinematically linear\ud regime, by combining the theory of single crystal plasticity as formulated in Gurtin et al. (2010) and\ud the phase-field formulation for ductile fracture proposed by Ambati et al. (2015) . The model introduces\ud coupling between plasticity and fracture through the dependency of the so-called degradation function\ud from a scalar global measure of the accumulated plastic strain on all slip systems. A viscous regularization\ud is introduced both in the treatment of plasticity and in the phase-field evolution equation. Testing of\ud the model on two examples for face centred cubic single crystals indicates that fracture is predicted to\ud initiate and develop in the regions of the maximum accumulated plastic strain, which is in agreement\ud with phenomenological observations. A rotation of the crystallographic unit cell is shown to affect the\ud test results in terms of failure pattern and corresponding global and local response.

Milan, Italy. I. Crivelli-Visconti Ed.

Singapore. K.H. Tan Ed.

The penalty method for the solution of contact problems yields an approximate satisfaction of the contact constraints. Augmentation schemes, which can be adopted to improve the solution, either include the contact forces as additional unknowns or are strongly affected by the penalty parameter and display a poor conver- gence rate. In a previous investigation, an unconventional augmentation scheme was proposed, on the basis of estimating the ‘exact’ values of the contact forces through linear interpolation of a database extracted by the previous converged states. An enhanced version of this method is proposed herein. With respect to the original method, the enhanced one eliminates some numerical problems and improves the regularity of the convergence path by carrying out the estimate through linear regression methods. The resulting convergence rate is superlinear, and the method is quite insensitive to the penalty parameter. The main underlying con- cept is that, within the iterative solution of a non-linear problem, linear regression techniques may be used as a tool to ‘shoot’ faster to the final solution, on the basis of a set of intermediate data. The generality of this concept makes it potentially applicable to contact problems in more general settings, as well as to other categories of non-linear problems.

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This paper focuses on the application of NURBS-based isogeometric analysis to Coulomb frictional contact problems between deformable bodies, in the context of large deformations. A mortar-based approach is presented to treat the contact constraints, whereby the discretization of the continuum is performed with arbitrary order NURBS, as well as C0-continuous Lagrange polynomial elements for comparison purposes. The numerical examples show that the proposed contact formulation in conjunction with the NURBS discretization delivers accurate and robust predictions. Results of lower quality are obtained from the Lagrange discretization, as well as from a different contact formulation based on the enforcement of the contact constraints at every integration point on the contact surface. © 2011 John Wiley & Sons, Ltd.

In this paper we focus on the prediction of mode-I debonding for a double cantilever beam (DCB). Among the various modeling approaches available, the Cohesive Crack Model (CCM) and Finite Fracture Mechanics (FFM) are selected for the analytical investigation, due to their ability to reconcile the stress- and energy-based approaches. The specimen is considered as an assemblage of two identical beams partly bonded together by an initially elastic interface. After the elastic stage, according to the CCM approach, it is assumed that, ahead of the physical crack tip, there exists a cohesive zone where the interface behavior is described by a stress-separation law. The interfacial stresses and length of the process zone are determined in closed form, along with the global load-displacement response. The method is first compared to the simple beam theory (SBT) and the enhanced beam theory (EBT) approaches, which are found to provide larger values of the debonding load; the difference between predictions of CCM and SBT/EBT is more pronounced for less brittle interfaces, i.e. for larger process zones. Then the analytical solution obtained by means of FFM is presented, which, despite being simply based on the elastic foundation model, closely matches the CCM results. Finally a numerical solution is achieved by a finite element analysis where generalized zero-thickness contact interface elements are adopted. An excellent agreement with these results confirms the good performance of the proposed CCM and FFM approaches.