A Generalized Finite Element Method for polycrystals with discontinuous grain boundaries

We present a Generalized Finite Element Method for the analysis of polycrystals with explicit treatment of grain boundaries. Grain boundaries and junctions, understood as loci of possible displacement discontinuity, are inserted into finite elements by exploiting the partition of unity property of finite element shape functions. Consequently, the finite element mesh does not need to conform to the polycrystal topology. The formulation is outlined and a numerical example is presented to demonstrate the potential and accuracy of the approach. The proposed methodology can also be used for branched and intersecting cohesive cracks, and comparisons are made to a related approach (Int. J. Numer

Materials science experiments in space

The criteria for the selection of the experimental areas and individual experiments were that the experiment or area must make a meaningful contribution to the field of material science and that the space environment was either an absolute requirement for the successful execution of the experiment or that the experiment can be more economically or more conveniently performed in space. A number of experimental areas and individual experiments were recommended for further consideration as space experiments. Areas not considered to be fruitful and others needing additional analysis in order to determine their suitability for conduct in space are also listed. Recommendations were made concerning the manner in which these materials science experiments are carried out and the related studies that should be pursued

Clearing-induced tissue shrinkage:A novel observation of a thickness size effect

The use of clearing agents has provided new insights in various fields of medical research (developmental biology, neurology) by enabling examination of tissue architecture in 3D. One of the challenges is that clearing agents induce tissue shrinkage and the shrinkage rates reported in the literature are incoherent. Here, we report that for a classical clearing agent, benzyl-alcohol benzyl-benzoate (BABB), the shrinkage decreases significantly with increasing sample size, and present an analytical formula describing this

Isolated cerebellar metastasis from urothelial carcinoma:A case report of a rare phenomenon

Introduction: Although urothelial carcinoma (UC) generally is non-invasive, contrastingly in 25% of patients UC metastasizes. Isolated central nervous system (CNS) metastasis from UC without other distant metastases are considered rare. In this report we describe a patient with an isolated and solitary cerebellar metastasis from UC. Research question: In this case report we explore the value of histological analysis of CNS metastases, imaging, treatment options and survival. Material and methods: A rare case is presented of a patient diagnosed with an isolated CNS metastasis originating from UC. Through a systematic review of literature route of dissemination, current imaging and treatment options, and survival are discussed.Results: A 77-year-old male was diagnosed with a pT2N0M0 high-grade UC and treated with transurethral resection and chemoradiation therapy. Several months later, the patient presented with neurological symptoms, and radiological imaging revealed a solitary cerebellar mass. A body CT scan showed no other metastasis. After surgical resection, histology confirmed urothelial origin of the mass, matching his primary UC and the patient received post-operative stereotactic radiotherapy at the surgical site. Recurrence of the cerebellar mass occurred after 6 months for which the patient received re-resection. The patient died 5.5 months after re-resection. Discussion and conclusion: Isolated brain metastases without other distant metastases from UC are rare, so histologic confirmation of the brain metastasis is essential, particularly when the time interval between diagnosis of the UC and brain metastasis increases. Early brain CT is not recommended. PET CT may have additional value in detection of other distant metastases from UC. Despite advancements in treatments, prognosis for CNS metastasis from UC remains poor

Isolated cerebellar metastasis from urothelial carcinoma:A case report of a rare phenomenon

Introduction: Although urothelial carcinoma (UC) generally is non-invasive, contrastingly in 25% of patients UC metastasizes. Isolated central nervous system (CNS) metastasis from UC without other distant metastases are considered rare. In this report we describe a patient with an isolated and solitary cerebellar metastasis from UC. Research question: In this case report we explore the value of histological analysis of CNS metastases, imaging, treatment options and survival. Material and methods: A rare case is presented of a patient diagnosed with an isolated CNS metastasis originating from UC. Through a systematic review of literature route of dissemination, current imaging and treatment options, and survival are discussed.Results: A 77-year-old male was diagnosed with a pT2N0M0 high-grade UC and treated with transurethral resection and chemoradiation therapy. Several months later, the patient presented with neurological symptoms, and radiological imaging revealed a solitary cerebellar mass. A body CT scan showed no other metastasis. After surgical resection, histology confirmed urothelial origin of the mass, matching his primary UC and the patient received post-operative stereotactic radiotherapy at the surgical site. Recurrence of the cerebellar mass occurred after 6 months for which the patient received re-resection. The patient died 5.5 months after re-resection. Discussion and conclusion: Isolated brain metastases without other distant metastases from UC are rare, so histologic confirmation of the brain metastasis is essential, particularly when the time interval between diagnosis of the UC and brain metastasis increases. Early brain CT is not recommended. PET CT may have additional value in detection of other distant metastases from UC. Despite advancements in treatments, prognosis for CNS metastasis from UC remains poor

Spatial fluctuations in transient creep deformation

We study the spatial fluctuations of transient creep deformation of materials as a function of time, both by Digital Image Correlation (DIC) measurements of paper samples and by numerical simulations of a crystal plasticity or discrete dislocation dynamics model. This model has a jamming or yielding phase transition, around which power-law or Andrade creep is found. During primary creep, the relative strength of the strain rate fluctuations increases with time in both cases - the spatially averaged creep rate obeys the Andrade law $\epsilon_t \sim t^{-0.7}$, while the time dependence of the spatial fluctuations of the local creep rates is given by $\Delta \epsilon_t \sim t^{-0.5}$. A similar scaling for the fluctuations is found in the logarithmic creep regime that is typically observed for lower applied stresses. We review briefly some classical theories of Andrade creep from the point of view of such spatial fluctuations. We consider these phenomenological, time-dependent creep laws in terms of a description based on a non-equilibrium phase transition separating evolving and frozen states of the system when the externally applied load is varied. Such an interpretation is discussed further by the data collapse of the local deformations in the spirit of absorbing state/depinning phase transitions, as well as deformation-deformation correlations and the width of the cumulative strain distributions. The results are also compared with the order parameter fluctuations observed close to the depinning transition of the 2$d$ Linear Interface Model or the quenched Edwards-Wilkinson equation.Comment: 27 pages, 18 figure

878-6 Stenting under intravascular ultrasound guidance of coronary bifurcation lesions with a new device allowing provisional side branch treatment

Vallmitjana Barbany, Venanci (escultor)Gran pla general de la font del 1919. Construida en marbre blanc, mesura 6,53 x 4,14 x 4,14 metres

Forces acting on the maxillary incisor teeth during laryngoscopy using the Macintosh laryngoscope

We determined the forces on the maxillary incisors during routine laryngoscopy in 65 adult patients. The forces were measured by a strain gauge based sensor positioned between the handle and the blade of the laryngoscope. The mean maximal force acting on the maxillary incisors was 49 N. In patients without maxillary incisors, the force acting on the gums was significantly lower at 21N (p < 0.001). These results suggest that, despite traditional advice to the contrary, a levering movement of the laryngoscope, using the maxillary incisors (or gums) as a fulcrum, is common practice. Biomechanical analysis revealed that, although levering is not the preferred movement, it is an efficient way of bringing the glottis into view. These results may have implications for future laryngoscope design

Microarray-based transcriptional profiling of Eimeria bovis-infected bovine endothelial host cells

Within its life cycle Eimeria bovis undergoes a long lasting intracellular development into large macromeronts in endothelial cells. Since little is known about the molecular basis of E. bovis-triggered host cell regulation we applied a microarray-based approach to define transcript variation in bovine endothelial cells early after sporozoite invasion (4 h post inoculation (p.i.)), during trophozoite establishment (4 days p.i.), during early parasite proliferation (8 days p.i.) and towards macromeront maturation (14 days p.i.). E. bovis infection led to significant changes in the abundance of many host cell gene transcripts. As infection progressed, the number of regulated genes increased such that 12, 45, 175 and 1184 sequences were modulated at 4 h, 4, 8 and 14 days p.i., respectively. These genes significantly interfered with several host cell functions, networks and canonical pathways, especially those involved in cellular development, cell cycle, cell death, immune response and metabolism. The correlation between stage of infection and the number of regulated genes involved in different aspects of metabolism suggest parasite-derived exploitation of host cell nutrients. The modulation of genes involved in cell cycle arrest and host cell apoptosis corresponds to morphological in vitro findings and underline the importance of these aspects for parasite survival. Nevertheless, the increasing numbers of modulated transcripts associated with immune responses also demonstrate the defensive capacity of the endothelial host cell. Overall, this work reveals a panel of novel candidate genes involved in E. bovis-triggered host cell modulation, providing a valuable tool for future work on this topic