A computational framework for gradient‐enhanced damage

A gradient‐enhanced damage model is combined with finite viscoelasticity and implemented in an Abaqus user subroutine, exploiting the heat equation solution capabilities for the damage regularisation, in order to simulate soft polymers. This regularised damage approach provides the advantage of mesh independent results and avoids localisation effects. In this work, a self‐diagnostic poly(dimethylsiloxane) (PDMS) elastomer is chosen as an example. To this end, an efficient two‐step parameter identification framework is developed to calibrate the corresponding model parameters

Gradient-enhanced modelling of damage for rate-dependent material behaviour - a parameter identification framework

The simulation of complex engineering components and structures under loads requires the formulation and adequate calibration of appropriate material models. This work introduces an optimisation-based scheme for the calibration of viscoelastic material models that are coupled to gradient-enhanced damage in a finite strain setting. The parameter identification scheme is applied to a self-diagnostic poly(dimethylsiloxane) (PDMS) elastomer, where so-called mechanophore units are incorporated within the polymeric microstructure. The present contribution, however, focuses on the purely mechanical response of the material, combining experiments with homogeneous and inhomogeneous states of deformation. In effect, the results provided lay the groundwork for a future extension of the proposed parameter identification framework, where additional field-data provided by the self-diagnostic capabilities can be incorporated into the optimisation scheme

Kombination von Disinhibierungsprotokollen zur Erhöhung der kortikospinalen Erregbarkeit

Während der Vorstellung einer Bewegung (motor imagery, MI) erhöht sich die kortikospinale Erregbarkeit, d.h. die Muskelantwort nach einem externen Impuls über dem korrespondierenden motorischen Kortex. Diese erhöhte Erregbarkeit hält jedoch nicht nach der Bewegungsvorstellung an. In der vorliegenden Studie wurde MI mit transkranieller magnetischer Stimulation (TMS) des korrespondierenden motorischen Hirnareals kombiniert. Hierbei wurde ein spezielles Stimulationsmuster eingesetzt: Ein repetitives, disinhibierendes TMS-Protokoll (DIS) mit gepaarten Pulsen, die für jeden Probanden individuell angepasst wurden, um bestimmte Neuronen- Verbindungen zu aktivieren (short-interval intra-cortical facilitation, SICF) und andere zu disinhibieren (late cortical disinhibition, LCD). Insgesamt wurden bei 15 gesunde Probanden in randomisierter Reihenfolge vier verschiedene Interventionen an unterschiedlichen Tagen durchgeführt: Bewegungsvorstellung einer Handöffnung (MI), TMS über dem kortikalen Handareal (DIS) und zwei kombinierten MI/DIS-Interventionen mit einer unterschiedlichen Anzahl an Impulsen (48 vs. 480). Lediglich die beiden MI/DIS- Konditionen führten zu einer Erhöhung der kortikospinalen Erregbarkeit nach der Intervention, wobei die höhere Interventionsdosis anhaltende Effekte zeigte. Diese plastischen Effekte traten auf, ohne dass die Probanden aktive Bewegungen durchführen mussten. Deswegen sollte in zukünftigen Studien untersucht werden, ob diese Interventionsart auch als Therapie für Patienten in Frage kommt, bei denen aktive Bewegungen nicht mehr möglich sind, z.B. bei Schlaganfall-Patienten mit einer Lähmung der Hand

Does nasal colonization with Methicillin-resistant Staphylococcus aureus (MRSA) in pig farmers persist after holidays from pig exposure?

In Germany, it has been reported that up to 86% of pig farmers are colonized with Methicillin-resistant Staphylococcus aureus (MRSA) in the nares, at least intermittently. However, little is known about the long-term persistence of colonization, especially when the farmers do not have daily contact to pigs. Here, we analyzed whether an absence from work during the summer holidays had an impact on nasal MRSA colonization rates of pig farmers

Processes, Roles and Their Interactions

Taking an interaction network oriented perspective in informatics raises the challenge to describe deterministic finite systems which take part in networks of nondeterministic interactions. The traditional approach to describe processes as stepwise executable activities which are not based on the ordinarily nondeterministic interaction shows strong centralization tendencies. As suggested in this article, viewing processes and their interactions as complementary can circumvent these centralization tendencies. The description of both, processes and their interactions is based on the same building blocks, namely finite input output automata (or transducers). Processes are viewed as finite systems that take part in multiple, ordinarily nondeterministic interactions. The interactions between processes are described as protocols. The effects of communication between processes as well as the necessary coordination of different interactions within a processes are both based on the restriction of the transition relation of product automata. The channel based outer coupling represents the causal relation between the output and the input of different systems. The coordination condition based inner coupling represents the causal relation between the input and output of a single system. All steps are illustrated with the example of a network of resource administration processes which is supposed to provide requesting user processes exclusive access to a single resource.Comment: In Proceedings IWIGP 2012, arXiv:1202.422

Ground Truthing CALPUFF and AERMOD for Odor Dispersion from Swine Barns using Ambient Odor Assessment Techniques

A collaborative research effort by several institutions investigated the dispersion of odors from a swine production facility. Trained human receptors measured downwind odor concentrations from four tunnel-ventilated swine finishing barns near Story City, Iowa, during twenty measurement events conducted between June and November 2004. Odor concentrations were modeled for short time steps using CALPUFF and AERMOD atmospheric dispersion models to compare predicted and measured odor levels. Source emission measurements and extensive micrometeorological data were collected along with ambient odor measurements using the Nasal Ranger® device (St. Croix Sensory, St. Paul MN), Mask Scentometer, odor intensity ratings, and air sample analysis by dynamic triangular forced-choice olfactometry (DTFCO). AERMOD predictions fit the odor measurements slightly better than CALPUFF with predicted concentrations being about half those predicted by CALPUFF. The Mask Scentometer and Nasal Ranger® measurements related best to the dispersion model output, and scaling factors of 3.0 for CALPUFF and 2.4 for AERMOD suggested for the Nasal Ranger® and 0.5 for the Mask Scentometer (both models). Measurements obtained using the Nasal Ranger®, Mask Scentometer, and odor intensity ratings correlated well to each other, had the strongest linear relationships, and provided slopes (measured: modeled) closest to 1.0. Converting intensity ratings to a dilution to threshold concentration did not correlate and relate as well, and this method was deemed less desirable for ambient odor assessment. Collection of ambient air samples for analysis in a olfactometry laboratory displayed poor correlations with other methods and should not be used to assess ambient odors

Improved general health of international adoptees, but immunization status still insufficient

We studied the demographic and clinical data from 495 adopted children seen between January 2002 and January 2007 to evaluate the medical condition and immunization status of international adoptees. The data of children from Chinese origin (53.5%) were compared to children arriving from other countries. Medical problems requiring treatment were present in 42.8% of the children. Parasitic gastrointestinal infection (22.0%) and skin abnormalities (22.4%) were diagnosed most often. Hepatitis B (1.2%) and tuberculosis (1%) were documented in some children; HIV, hepatitis C, and syphilis were not seen in any of the children. Antibody levels against diphtheria and tetanus were insufficient in about half of all children, particularly in those from China. In conclusion, most adoptive children had a good general health, with only a few having major medical problems. Many adoptive children had an inadequate immunization status

The harm in conflating aging with accessibility

Including older adults as full stakeholders in digital society. </p

Elimusertib has anti-tumor activity in preclinical patient-derived pediatric solid tumor models

The small molecule inhibitor of ataxia telangiectasia and Rad3-related protein (ATR), elimusertib, is currently being tested clinically in various cancer entities in adults and children. Its preclinical anti-tumor activity in pediatric malignancies, however, is largely unknown. We here assessed the preclinical activity of elimusertib in 38 cell lines and 32 patient-derived xenograft (PDX) models derived from common pediatric solid tumor entities. Detailed in vitro and in vivo molecular characterization of the treated models enabled the evaluation of response biomarkers. Pronounced objective response rates were observed for elimusertib monotherapy in PDX, when treated with a regimen currently used in clinical trials. Strikingly, elimusertib showed stronger anti-tumor effects than some standard of care chemotherapies, particularly in alveolar rhabdomysarcoma PDX. Thus, elimusertib has strong preclinical anti-tumor activity in pediatric solid tumor models, which may translate to clinically meaningful responses in patients

Multiproxy analysis of a new terrestrial and a marine Cretaceous–Paleogene (K–Pg) boundary site from New Zealand

Author Posting. © The Author(s), 2010. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Geochimica et Cosmochimica Acta 75 (2011): 657-672, doi:10.1016/j.gca.2010.10.016.An integrated study of palynology, Mössbauer spectroscopy, mineralogy and osmium isotopes has led to the detection of the first K-Pg boundary clay layer in a Southern Hemisphere terrestrial setting. The K-Pg boundary layer was independently identified at centimetre resolution by all the above mentioned methods at the marine K-Pg boundary site of mid-Waipara and the terrestrial site of Compressor Creek (Greymouth coal field), New Zealand. Mössbauer spectroscopy shows an anomaly of Fe-containing particles in both K-Pg boundary sections: jarosite at mid-Waipara and goethite at Compressor Creek. This anomaly coincides with a turnover in vegetation indicated by an interval dominated by fern spores and extinction of key pollen species in both sections. In addition to the terrestrial floristic changes, the mid-Waipara section reveals a turnover in the dinoflagellate assemblages and the appearance of global earliest Danian index species. Geochemical data reveal relatively small iridium enrichments in the boundary layers of 321 pg/g at mid-Waipara and 176 pg/g at Compressor Creek. Unradiogenic 187Os/188Os values of the boundary clay reveal the presence of a significant extraterrestrial component. We interpret the accumulation of Fe nano-phases at the boundary as originating from both the impactor and the crystalline basement target rock. The goethite and jarosite are interpreted as secondary phases formed by weathering and diagenesis. The primary phases were probably controlled by the initial composition of the vapor plume and condensation kinetics rather than condensation thermodynamics. This investigation indicates that identification of Fe in nano-phases by Mössbauer spectroscopy is an accurate and cost-effective method for identifying impact event horizons and it efficiently complements widely used biostratigraphic and geochemical methods.V. Vajda acknowledges the financial support provided by the Swedish Royal Academy of Sciences through the Knut & Alice Wallenbergs Foundation and from the Crafoord Foundation. P.S. Willumsen acknowledges financial support from the Carlsberg Foundation no.2008_01_0404