Some general observations relating to tyre shear forces and road surfaces are followed by more specific considerations from circuit racing. The discussion then focuses on the mechanics of rubber ...friction. The classical experiments of Grosch are outlined and the interpretations that can be put on them are discussed. The interpretations involve rubber viscoelasticity, so that the vibration properties of rubber need to be considered. Adhesion and deformation mechanisms for energy dissipation at the interface between rubber and road and in the rubber itself are highlighted. The enquiry is concentrated on energy loss by deformation or hysteresis subsequently. Persson's deformation theory is outlined and the material properties necessary to apply the theory to Grosch's experiments are discussed. Predictions of the friction coefficient relating to one particular rubber compound and a rough surface are made using the theory and these are compared with the appropriate results from Grosch. Predictions from Persson's theory of the influence of nominal contact pressure on the friction coefficient are also examined. The extent of the agreement between theory and experiment is discussed. It is concluded that there is value in the theory but that it is far from complete. There is considerable scope for further research on the mechanics of rubber friction.
In order to investigate an almost pure extrinsic size effect we propose an experimental approach to investigate the deformation structure within single crystalline cross-sections of twisted ...bamboo-structured Au microwires. The cross-sections of individual 〈100〉 oriented grains of 25μm thick Au microwires have been characterized by Laue microdiffraction. The diffraction data were used to calculate the misorientation of each data point with respect to the neutral fiber in the center of the cross-section as well as the kernel average misorientation to map the global and local deformation structure as function of the imposed maximum plastic shear strain. The study is accompanied by crystal plasticity simulations which yield the equivalent plastic strain distributions in the cross-section of the wire. The global deformation structures are directly related to the activated slip systems, resulting from the real orientations of the investigated grains. When averaging the degree of deformation along ring segments, an almost continuous but non-linear increase of misorientation from the center toward the surface is observed, reflecting the overall strain gradient imposed by torsion. For the local deformation structure, pronounced and graded deformation traces are observed which often pass over the neutral fiber of the twisted wire and which are obviously reflecting domains of high geometrically necessary dislocations content.
Dynamic perception includes amodal and modal completion, along with apparent movement. It fills temporal gaps for single objects. In 2 experiments, using 6 stimulus presentation conditions involving ...3 sensory modalities, participants experienced 8–10 sequential stimuli (200 ms each) with interstimulus intervals (ISIs) of 0.25–7.0 s. Experiments focused on spatiotemporal completion (walking), featural completion (object changing), auditory completion (falling bomb), and haptic changes (insect crawling). After each trial, participants judged whether they experienced the process of “happening” or whether they simply knew that the process must have occurred. The phenomenon was frequency independent, being reported at short ISIs but not at long ISIs. The phenomenon involves dynamic modal completion and possibly also conceptual processes.
ABSTRACT
BACKGROUND AND PURPOSE
Susceptibility‐weighted magnetic resonance imaging (SWI) yields information regarding tumor biology (e.g., hemorrhage) of growing gliomas. SWI changes can also be ...observed as a consequence of treatment, for example radiation therapy. The aim of our study was to investigate how susceptibility changes occur during the time course after completion of standard treatment in newly diagnosed glioblastoma (GBM).
METHODS
Eighteen GBM patients were retrospectively analyzed. After completion of therapy, imaging was performed every 3 months. MRI was analyzed at the following time points: after the third and sixth cycle of adjuvant temozolomide chemotherapy, thereafter in 3 month intervals and at recurrence. The number of SWI positive tumor pixels was quantified and compared with progression as defined by the RANO criteria on T2‐ and contrast‐enhanced T1‐weighted MRI sequences (T1‐CE).
RESULTS
The MRI interval between completion of the sixth chemotherapy cycle and last MRI before progression was 390 ± 292 days. Between the last MRI before progression and at progression a significant increase in SWI positive tumor pixels was observed (P = .012), whereas tumor size remained unchanged (RANO T2: P = .385; RANO T1‐CE: P = .165). The number of SWI positive pixels remained unchanged between last MRI before progression until progression (P = .149), whereas RANO T2 and T1‐CE showed tumor progression (interval 128 ± 69 days).
CONCLUSIONS
SWI positive pixel count increases significantly prior to changes in tumor size (RANO). Our findings may be explained by microbleeds compatible with stimulation of angiogenesis and possibly serve as an early biomarker of tumor progression.
The superfamily of the protein kinase C (PKC) comprises ten isozymes and is widely known for its key role in signal transduction. Protein kinase Cε (PKCε) is known to play key roles in tumor ...suppression. PKCε requires activation to interact with RACK2, and the adaptor protein then translocates activated PKCε to subcellular sites within the proximity of their substrates. An EAVSLKPT peptide interferes with the interaction of PKCε and its adaptor protein RACK2. Since signaling in the malignant cells are sufficiently changed then the scope and limitations of PKCe as a anticancer drug target has to be estimated more clearly. Acquiring isozyme-selective inhibitors is a difficult task due to the high sequence similarity within the ten PKCs. Small molecule-disruptors of the PKCε/RACK2 protein–protein interaction could suppress PKCε signaling and reduce malignant properties. The EAVSLKPT peptide was used as a base of a pharmacophore model. Thieno2,3-bquinolines as a wide cluster of specific small-molecule inhibitors of the PKCε/RACK2 protein–protein interaction and PKCε signaling were revealed. The structural features of active thieno2,3-bquinolines were expanded on the basis of this pharmacophore model. The interaction between PKCε and RACK2 was measured using an ELISA-based assay. It was found that
N
-(4-acetylphenyl)-3-amino-6,7-ethelendioxy-thieno2,3-bquinoline-2-carboxamide (
1b
) shows promising inhibitory activities on the interaction of PKCε with its adaptor protein, the receptor for activated C-kinase 2 (RACK2), hence interfering with PKCε signaling. Both
1a
and
1b
did not show some cytotoxic properties on susceptible PC-3 cell line but both active compounds showed a significant antisprouting activity. The quinolines without thiophene ring as “open” analogs of
1b
were inactive in primary assays. A structural isomer of (
1a
meta-acetyl), compound (
1b
para
-acetyl) was found to exhibit, in addition to strong inhibitory activity on PKCε signaling with an IC
50
of 4.25 µM, also anti-angiogenic activities. Thus thieno2,3-bquinolines
1a
and
1b
could be reliable and selective biochemical tools to investigate of PKCe/RACK2 effects.
Introduction
Diversity has become a key-strategic element of success in various political and economic fields. The European Society of Intensive Care Medicine (ESICM) decided to make diversity a key ...strategic priority for the future and appointed a Task-Force on this topic.
Methods
In a consensus process, three Working-Groups, nominated by Task-Force members, developed statements on strategic future topics. In addition, diversity-related data available from the membership database have been analyzed and reported in aggregated form.
Results
The Task-Force decided to nominate working groups on (1) “sex, gender identity and sexual orientation”, (2) “ethnicity, culture and socio-economic status”, and (3) “multiprofessionalism”. These are the first prioritized topics for the near future. The first diversity-report shows targetable items in all three domains.
Conclusion
The diversity Task-Force defined actionable items for a one- and three-year plan that are especially aiming at the identification of potential gaps and an implementation of concrete projects for members of the ESICM.
Built to Grow Imhof, Barbara; Gruber, Petra
2016, 2015, 2016-01-15
eBook
Built to Grow investigates patterns of growth and dynamics in nature with the aim of creating a new "living architecture" that can be applied to architectonic designs. It examines biological ...processes to identify basic principles of growth and translate them into exemplary architectonic ideas and visions. The project brings together experts from the fields of architecture, biology, art, mechatronics, and robotics.
Currently, the standard method of programming industrial robots is to perform it manually, which is cumbersome and time-consuming. Thus, it can be a burden for the flexibility of inspection systems ...when a new component with a different design needs to be inspected. Therefore, developing a way to automate the task of generating a robotic trajectory offers a substantial improvement in the field of automated manufacturing and quality inspection. This paper proposes and evaluates a methodology for automatizing the process of scanning a 3D surface for the purpose of quality inspection using only visual feedback. The paper is divided into three sub-tasks in the same general setting: (1) autonomously finding the optimal distance of the camera on the robot’s end-effector from the surface, (2) autonomously generating a trajectory to scan an unknown surface, and (3) autonomous localization and scan of a surface with a known shape, but with an unknown position. The novelty of this work lies in the application that only uses visual feedback, through the image focus measure, for determination and optimization of the motion. This reduces the complexity and the cost of such a setup. The methods developed have been tested in simulation and in real-world experiments and it was possible to obtain a precision in the optimal pose of the robot under 1 mm in translational, and 0.1
∘
in angular directions. It took less than 50 iterations to generate a trajectory for scanning an unknown free-form surface. Finally, with less than 30 iterations during the experiments it was possible to localize the position of the surface. Overall, the results of the proposed methodologies show that they can bring substantial improvement to the task of automatic motion generation for visual quality inspection.
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