Hysteresis in a system driven by either generalized force or displacement variables: martensitic phase transition in single-crystalline Cu-Zn-Al

We report on experiments aimed at comparing the hysteretic response of a Cu-Zn-Al single crystal undergoing a martensitic transition under strain-driven and stress-driven conditions. Strain-driven experiments were performed using a conventional tensile machine while a special device was designed to perform stress-driven experiments. Significant differences in the hysteresis loops were found. The strain-driven curves show reentrant behavior yield point which is not observed in the stress-driven case. The dissipated energy in the stress-driven curves is larger than in the strain-driven ones. Results from recently proposed models qualitatively agree with experiments.

Monitoring tumor antigen specific T-cell responses in cancer patients and phase I clinical trials of peptide-based vaccination.

Numerous phase I and II clinical trials testing the safety and immunogenicity of various peptide vaccine formulations based on CTL-defined tumor antigens in cancer patients have been reported during the last 7 years. While specific T-cell responses can be detected in a variable fraction of immunized patients, an even smaller but significant fraction of these patients have objective tumor responses. Efficient therapeutic vaccination should aim at boosting naturally occurring antitumor T- and B-cell responses and at sustaining a large number of tumor antigen specific and fully functional effector T cells at tumor sites. Recent progress in our ability to quantitatively and qualitatively monitor tumor antigen specific CD8 T-cell responses will greatly help in making rapid progress in this field.

PRECISION V: Randomisierte Phase II-Studie mit Drug Eluting Beads (DEB) zur Behandlung des hepatozelluläre Karzinoms (HCC) mittels transarterieller Chemoemblisation [PRECISION V: Randomized Phase II-Study with Drug Eluting Beads (DEB) for the Treatment of Hepatocellular cancer (HCC) using transarterial Chemoemblisation.]

Zielsetzung: Vergleich von Drug Eluting Bead (DEB)-TACE mit konventioneller TACE bei der Behandlung von ,,intermediate stage-HCC bei Patienten mit Zirrhose. Material und Methodik: 212 Patienten (185 ♂, 27 ♀; mittleres Alter, 67 Jahre) mit Child-Pugh A oder B Leberzirrhose und großem und/oder multinodulärem, irresektablen HCC wurden randomisiert, um das Therapieansprechen nach der Behandlung mit DEB (DC Bead; Biocompatibles, UK) beladen mit Doxorubicin oder konventioneller TACE mit Doxorubicin zu vergleichen. Die Randomisierung wurde nach Child-Pugh Status (A oder B), Performance Status (ECOG 0 oder 1), bilobärer Erkrankung (ja/nein) und frühere kurative Behandlung (ja/nein) stratifiziert. Der primäre Studienendpunkt war das 6-Monats-Tumoransprechen. Eine unabhängige verblindete MRT-Studie wurde durchgeführt, um das Tumoransprechen nach den RECIST Kriterien zu beurteilen. Ergebnisse: DEB-TACE mit Doxorubicin zeigte eine höhere Rate an komplettem Tumoransprechen, objektivem Ansprechen und Tumorkontrolle im Vergleich zur konventionellen TACE (27% vs 22%; 52% vs 44%; and 63% vs 52%; P>0.05). Patienten mit Child-Pugh B Zirrhose, ECOG 1 Performance Status, bilobärer Erkrankung und Rezidiven nach kurativer Behandlung zeigte einen signifikanten Anstieg des objektiven Ansprechens (p = 0.038) im Vergleich zur Kontrollgruppe. Bei Patienten, die mit DEB-TACE behandelt wurden, konnte eine deutliche Reduktion der gravierenden Lebertoxizität erreicht werden. Die Doxorubicin-Nebenwirkungsrate war in der DEB-TACE Gruppe deutlich geringer (p = 0.0001) als in der konventionellen TACEGruppe. Schlussfolgerung: DEB-TACE mit Doxorubicin ist sicher und effektiv in der Behandlung von ,,intermediate-stage HCC und bietet einen signifikanten Vorteil bei Patienten mit fortgeschrittener Erkrankung.

Safety and Mobility Impacts of Winter Weather – Phase I, August 2011

Highway agencies spend millions of dollars to ensure safe and efficient winter travel. However, the effectiveness of winter weather maintenance practices on safety and mobility are somewhat difficult to quantify. Phase I of this project investigated opportunities for improving traffic safety on state-maintained roads in Iowa during winter weather conditions. The primary objective was to develop several preliminary means for the Iowa Department of Transportation (DOT) to identify locations of possible interest systematically with respect to winter weather-related safety performance based on crash history. Specifically, metrics were developed to assist in identifying possible habitual, winter weather-related crash sites on state-maintained rural highways in Iowa. In addition, the current state of practice, for both domestic and international highway agency practices, regarding integration of traffic safety- and mobility-related data in winter maintenance activities and performance measures were investigated. This investigation also included previous research efforts. Finally, a preliminary work plan, focusing on systematic use of safety-related data in support of winter maintenance activities and site evaluation, was prepared.

Delta(1232) isobar excitations in nuclear many-body systems from varios NN interactions.

Delta isobar components in the nuclear many-body wave function are investigated for the deuteron, light nuclei (16O), and infinite nuclear matter within the framework of the coupled-cluster theory. The predictions derived for various realistic models of the baryon-baryon interaction are compared to each other. These include local (V28) and nonlocal meson exchange potentials (Bonn2000) but also a model recently derived by the Salamanca group accounting for quark degrees of freedom. The characteristic differences which are obtained for the NDelta and Delta Delta correlation functions are related to the approximation made in deriving the matrix elements for the baryon-baryon interaction.

Delta(1232) isobar excitations and the ground state of nuclei

The influence of Delta isobar components on the ground-state properties of nuclear systems is investigated for nuclear matter as well as finite nuclei. Many-body wave functions, including isobar configurations and binding energies, are evaluated employing the framework of the coupled-cluster theory. It is demonstrated that the effect of isobar configurations depends in a rather sensitive way on the model used for the baryon-baryon interaction. As examples for realistic baryon-baryon interactions with explicit inclusion of isobar channels we use the local (V28) and nonlocal meson-exchange potentials (Bonn2000) but also a model recently developed by the Salamanca group, which is based on a quark picture. The differences obtained for the nuclear observables are related to the treatment of the interaction, the pi-exchange contributions in particular, at high momentum transfers.

Liquid-gas phase transition in nuclear matter from realistic many-body approaches

The existence of a liquid-gas phase transition for hot nuclear systems at subsaturation densities is a well-established prediction of finite-temperature nuclear many-body theory. In this paper, we discuss for the first time the properties of such a phase transition for homogeneous nuclear matter within the self-consistent Green's function approach. We find a substantial decrease of the critical temperature with respect to the Brueckner-Hartree-Fock approximation. Even within the same approximation, the use of two different realistic nucleon-nucleon interactions gives rise to large differences in the properties of the critical point.

p21 as a transcriptional co-repressor of S-phase and mitotic control genes.

It has been previously described that p21 functions not only as a CDK inhibitor but also as a transcriptional co-repressor in some systems. To investigate the roles of p21 in transcriptional control, we studied the gene expression changes in two human cell systems. Using a human leukemia cell line (K562) with inducible p21 expression and human primary keratinocytes with adenoviral-mediated p21 expression, we carried out microarray-based gene expression profiling. We found that p21 rapidly and strongly repressed the mRNA levels of a number of genes involved in cell cycle and mitosis. One of the most strongly down-regulated genes was CCNE2 (cyclin E2 gene). Mutational analysis in K562 cells showed that the N-terminal region of p21 is required for repression of gene expression of CCNE2 and other genes. Chromatin immunoprecipitation assays indicated that p21 was bound to human CCNE2 and other p21-repressed genes gene in the vicinity of the transcription start site. Moreover, p21 repressed human CCNE2 promoter-luciferase constructs in K562 cells. Bioinformatic analysis revealed that the CDE motif is present in most of the promoters of the p21-regulated genes. Altogether, the results suggest that p21 exerts a repressive effect on a relevant number of genes controlling S phase and mitosis. Thus, p21 activity as inhibitor of cell cycle progression would be mediated not only by the inhibition of CDKs but also by the transcriptional down-regulation of key genes.