The High-Temperature Proton Conductor Strontium Zirconate: Thermogravimetry of Water Uptake

The water uptake of nominally 5%-Yb-doped strontium zirconate (SrZr_0.95Yb_0.05O_3−α) was studied in situ by thermogravimetry at different temperatures and water vapor pressures. The process could be described in terms of an ideal solution behavior, showing a lower effective vacancy concentration than that expected from the nominal dopant content. The solution reaction was found to have ΔS°=−127 J/(mol·K) and ΔH°=−106 kJ/mol.     

Computer attitude in psychiatric inpatients

Negative computer attitude has been shown to be a possible co-variable in computerized examinations of psychiatric patients, affecting patient–computer interaction as well as reliability and validity of assessments.It remains still uncertain if the psychological construct of computer attitude can be dependably measured in acute psychiatric inpatients or whether it is impeded by the effects of mental illness. For that reason a German translation of the Groningen Computer Attitude Scale (GCAS) was evaluated in 160 acute psychiatric inpatients under naturalistic conditions.General test criteria (internal structure, item analysis, internal consistency, split half reliability) to a large extent corresponded to those formerly found in healthy subjects and psychiatric outpatients. The mean GCAS score was calculated as 56.2 ± 10.8 points and a significantly better computer attitude was found in male, better educated and younger patients. Some diverging correlation patterns were found in diagnostic subgroups, indicating a possible minor impact of mental disorder on computer attitude.Overall, the GCAS was found to be a suitable instrument for measuring computer attitude in acute psychiatric inpatients. It should be used in identifying patients with a negative attitude to computers in order to ensure reliability and validity of computerized assessment.     

Enterprise JavaBeans

Large web-based information systems make high demands on scalability, maintainability, reliability and security. In order to ease the development of such systems appropriate software architectures are needed. These architectures have to take into account business aspects as well as requisite tools and products. Such an architecture is offered by Sun Microsystems in the form of the Enterprise JavaBeans specification. Based on our experience from different projects we undertake a close examination of this architecture.     

Generation of the isoprostane 8-epi-prostaglandin F2alpha in vitro and in vivo via the cyclooxygenases

F2-isoprostanes are isomers of the prostaglandin PGF2alpha. At least one compound of this group, 8-epi-PGF2alpha, exhibits biological activity, and therefore special interest is focused on the mechanism of isoprostane formation: enzyme catalyzed or radical mediated. We analyzed the formation of isoprostanes in vitro and in vivo. In both systems, purified cyclooxygenase isoenzymes and cell models specific for the cyclooxygenase isoenzymes, 8-epi-PGF2alpha formation could be totally suppressed by cyclooxygenase inhibitors. Indomethacin inhibited concentration-dependent 8-epi-PGF2alpha formation in platelets stimulated with calcium ionophore, arachidonic acid or thrombin. Nordihydroguaiaretic acid, an antioxidant, blocked isoprostane formation with a similar IC50 value as thromboxane B2 synthesis, pointing toward cyclooxygenase as the primary target of inhibition. Based on the turnover number, cyclooxygenase-2 formed higher levels of 8-epi-PGF2alpha than cyclooxygenase-1. Endogenous 8-epi-PGF2alpha production in rat mesangial cells correlated well with the mRNA and protein expression of cyclooxygenase-2 during interleukin-1 induction. However, in contrast to human platelets, which produced different forms of isoprostanes, rat mesangial cells appeared to form only 8-epi-PGF2alpha. Further, this indicates that mesangial cells may represent a cellular origin for renal 8-epi-PGF2alpha formation. Next, we analyzed the formation of isoprostanes in humans. A direct correlation was observed between indomethacin treatment and the decrease in 8-epi-PGF2alpha and isoprostane levels, but compared with other prostanoids the inhibition was less pronounced. In summary, based on the in vitro studies, a clear cyclooxygenase-dependent formation of isoprostanes, especially 8-epi-PGF2alpha, was observed. However, in vivo additional formation via cyclooxygenase enzyme-independent mechanisms is likely.     

An Improved On-line Contingency Screening for Power System Transient Stability Assessment

This paper presents a contingency screening method and a framework for its on-line implementation. The proposed method carries out contingency screening and on-line stability assessment with respect to first-swing transient stability. For that purpose, it utilizes the single machine equivalent method and aims at improving the prior developed contingency screening approaches. In order to determine vulnerability of the system with respect to a particular contingency, only one time-domain simulation needs to be performed. An early stop criteria is proposed so that in a majority of the cases the simulation can be terminated after a few hundred milliseconds of simulated system response. The method’s outcome is an assessment of the system’s stability and a classification of each considered contingency. The contingencies are categorized by exploiting parameters of an equivalent one machine infinite bus system. A novel island detection approach, appropriate for an on-line application since it utilizes efficient algorithms from graph theory and enables stability assessment of individual islands, is also introduced. The New England and New York system as well as the large-scale model of the Continental-European interconnected system are used to test the proposed method with respect to assessment accuracy and computation time.     

Ecological tax reform in Germany: handling two hot potatoes at the same time

Combining environmental with employment objectives, ecological tax reform (ETR) envisages a double dividend. While research has mainly focused on the socio-economic and environmental impacts of ETR, there is less literature on the social responses. This paper gives an overview and history of German ETR as well as investigating the understanding of perceptions and attitudes towards ETR of those being “subject to tax”. The research is based on qualitative social research methods. As with the other PETRAS papers, interviews were conducted with policy-makers and business leaders and focus groups were formed with lay persons. The results show that responses of policy-makers and business leaders are modest. Although some criticisms about the specific design of the German ETR remain, complaints towards ETR are settled. Attitudes appear influenced by more fundamental convictions such as economic interest or altruistic views. In contrast, ETR appears to politicise common people. Attitudes are influenced by the overall comprehension of the ETR concept, the expected impacts, perceived information deficits, as well as a general distrust in politics. Our data show that the linking of environmental and employment objectives is not understood and not welcomed. In order to increase social acceptance, the paper discusses refocusing ETR on environmental objectives, modestly increasing the share of ETR revenue spent for environmental purposes, removing inconsistencies in the ETR design, and improving information policy.     

Query language-based inverses of schema mappings: semantics, computation, and closure properties

The inversion of schema mappings has been identified as one of the fundamental operators for the development of a general framework for metadata management. During the last few years, three alternative notions of inversion for schema mappings have been proposed (Fagin-inverse (Fagin, TODS 32(4), 25:1–25:53, 2007), quasi-inverse (Fagin et?al., TODS 33(2), 11:1–11:52, 2008), and maximum recovery (Arenas et?al., TODS 34(4), 22:1–22:48, 2009)). However, these notions lack some fundamental properties that limit their practical applicability: most of them are expressed in languages including features that are difficult to use in practice, some of these inverses are not guaranteed to exist for mappings specified with source-to-target tuple-generating dependencies (st-tgds), and it has been futile to search for a meaningful mapping language that is closed under any of these notions of inverse. In this paper, we develop a framework for the inversion of schema mappings that fulfills all of the above requirements. It is based on the notion of ${\mathcal{C}}$ -maximum recovery, for a query language ${\mathcal{C}}$ , a notion designed to generate inverse mappings that recover back only the information that can be retrieved with queries in ${\mathcal{C}}$ . By focusing on the language of conjunctive queries (CQ), we are able to find a mapping language that contains the class of st-tgds, is closed under CQ-maximum recovery, and for which the chase procedure can be used to exchange data efficiently. Furthermore, we show that our choices of inverse notion and mapping language are optimal, in the sense that choosing a more expressive inverse operator or mapping language causes the loss of these properties.     

Innervation of developing human taste buds. An immunohistochemical study

1. Vinorelbine produced a dominant metabolite (M1) after incubation with rat liver microsomes. 2. Several major metabolites other than M1 were identified by HPLC in bile and faeces of rat after intravenous administration. 3. The structures of the major metabolites were identified as 15,16-epoxyvinorelbine (M1), 11'-hydroxyvinorelbine (M2), 19'-hydroxyvinorelbine (M3a), 15,16-epoxy-10'-hydroxyvinorelbine (M3b) and 10'-hydroxyvinorelbine (M4) by comparison of HPLC retention times and by extensive analyses of two-dimensional NMR and hybrid MS/MS spectra.     

Gene expression of matrix metalloproteinases 1, 3, and 9 by chondrocytes in osteoarthritic human knee articular cartilage is zone and grade specific

OBJECTIVES: Matrix metalloproteinases (MMPs) are thought to be major mediators of cartilage destruction. Osteoarthritis (OA) is characterised by cartilage degradation. This study explores gene expression of three MMPs in articular chondrocytes during the histological development of the cartilage lesion of OA. METHODS: Biopsy specimens of human normal and OA cartilage, classified into four grades on the basis of histology, were probed for MMPs 1, 3, and 9 using 35S-labelled cDNA probes. The signal was measured at four different depths (zones) using an automated image analyser and compared with signal from sections probed with lambda DNA. Rheumatoid synovium was used as a positive control for MMP gene expression. RESULTS: Rheumatoid tissue contained mRNA for all three MMPs. Expression in chondrocytes varied with the depth of the chondrocyte in the cartilage and the histomorphological extent of the OA changes. There was no detectable mRNA signal for these three MMPs in normal cartilage. In general, in OA, MMP-1 gene expression was greatest in the superficial cartilage in established disease. By contrast mRNAs for MMP-3 and 9 were expressed deeper in the cartilage, MMP-9 early in disease and MMP-3 with a biphasic pattern in early and late stage disease, most pronounced in the latter. This was a consequence of differential expression in single cells and chondrocyte clusters in late disease. CONCLUSION: The data indicate that expression of genes for MMPs 1, 3, and 9 is differentially regulated in human articular chondrocytes and, in individual cells, is related to the depth of the chondrocyte below the cartilage surface and the nature and extent of the cartilage lesion.