A Call to Arms: Revisiting Database Design

Good database design is crucial to obtain a sound, consistent database, and - in turn - good database design methodologies are the best way to achieve the right design. These methodologies are taught to most Computer Science undergraduates, as part of any Introduction to Database class. They can be considered part of the "canon", and indeed, the overall approach to database design has been unchanged for years. Moreover, none of the major database research assessments identify database design as a strategic research direction. Should we conclude that database design is a solved problem? Our thesis is that database design remains a critical unsolved problem. Hence, it should be the subject of more research. Our starting point is the observation that traditional database design is not used in practice - and if it were used it would result in designs that are not well adapted to current environments. In short, database design has failed to keep up with the times. In this paper, we put forth arguments to support our viewpoint, analyze the root causes of this situation and suggest some avenues of research.Comment: Removed spurious column break. Nothing else was change

Magnetic Properties of TbNi1 xAuxIn Compounds

Polycrystalline samples of $TbNi_{1-x}Au_{x}In$ for x = 0.1, 0.2, 0.4, 0.6 and 0.8 were prepared and studied by powder X-ray and neutron diffraction and ac magnetic susceptibility measurements. These compounds crystallize in the hexagonal ZrNiAl-type structure. With increasing Au content a change in the magnetic structure is observed. For x = 0.1, 0.2 and 0.4 the magnetic order is described by the propagation vector k = (1/2, 0, 1/2) while for x = 0.8 by k = (0, 0, 1/2). Between 1.5 K and the Néel temperature the magnetic order is stable

Using Forensics to Introduce IR Spectroscopy & Molecular Modeling

A student activity is reported that analyzes “medical evidence” with experimental and computational methods. The lesson demonstrates benefits of solving practical problems with integrated tools

The Titration Olympics

The “Titration Olympics” is the capstone experiment at the end of the Spring semester’s Advanced Chemistry Acid-Base-Buffer unit. In this lab exercise, students compete to determine the concentration of an unknown acid solution using a sodium hydroxide solution they prepare and standardize using KHP. The winner is determined using a rubric that accounts for (a) overall lab time, (b) preparation and general lab technique, (c) data table, (d) quality of the phenolphthalein endpoints, (e) accuracy of the unknown acid’s molarity, (f) use of significant figures, and (g) clean up skills. Students enjoy the competitive spirit of the experiment and realize the importance of meticulous technique to produce an effective and efficient titration. You will perform the student activity using the lab handout in this session. Challenge yourself to outperform our students

Mouse models for preeclampsia: disruption of redox-regulated signaling

The concept that oxidative stress contributes to the development of human preeclampsia has never been tested in genetically-defined animal models. Homozygous deletion of catechol-Omethyl transferase (Comt-/-) in pregnant mice leads to human preeclampsia-like symptoms (high blood pressure, albuminurea and preterm birth) resulting from extensive vasculo-endothelial pathology, primarily at the utero-fetal interface where maternal cardiac output is dramatically increased during pregnancy. Comt converts estradiol to 2-methoxyestradiol 2 (2ME2) which counters angiogenesis by depleting hypoxia inducible factor-1 alpha (HIF-1 alpha) at late pregnancy. We propose that in wild type (Comt++) pregnant mice, 2ME2 destabilizes HIF-1 alpha by inhibiting mitochondrial superoxide dismutase (MnSOD). Thus, 2ME2 acts as a pro-oxidant, disrupting redox-regulated signaling which blocks angiogenesis in wild type (WT) animals in physiological pregnancy. Further, we suggest that a lack of this inhibition under normoxic conditions in mutant animals (Comt-/-) stabilises HIF-1 alpha by inactivating prolyl hydroxlases (PHD). We predict that a lack of inhibition of MnSOD, leading to persistent accumulation of HIF-1 alpha, would trigger inflammatory infiltration and endothelial damage in mutant animals. Critical tests of this hypothesis would be to recreate preeclampsia symptoms by inducing oxidative stress in WT animals or to ameliorate by treating mutant mice with Mn-SOD-catalase mimetics or activators of PHD

Diammonium potassium citrate, (NH4)2KC6H5O7

The crystal structure of di­ammonium potassium citrate, 2NH(4) (+)·K(+)·C(6)H(5)O(7) (3−), has been solved and refined using laboratory X-ray powder diffraction data and optimized using density functional theory. The KO(7) coordination polyhedra are isolated. The ammonium cations and the hydro­phobic methyl­ene sides of the citrate anions occupy the spaces between the coordination polyhedra. Each hydrogen atom of the ammonium ions acts as a donor in a charge-assisted N—H⋯O, N—H⋯(O,O) or N—H⋯(O,O,O) hydrogen bond. There is an intra­molecular O—H⋯O hydrogen bond in the citrate anion between the hydroxide group and one of the terminal carboxyl­ate groups. [Image: see text

A Framework for Online Conformance Checking

Conformance checking – a branch of process mining – focuses on establishing to what extent actual executions of a process are in line with the expected behavior of a reference model. Current conformance checking techniques only allow for a-posteriori analysis: the amount of (non-)conformant behavior is quantified after the completion of the process instance. In this paper we propose a framework for online conformance checking: not only do we quantify (non-)conformant behavior as the execution is running, we also restrict the computation to constant time complexity per event analyzed, thus enabling the online analysis of a stream of events. The framework is instantiated with ideas coming from the theory of regions, and state similarity. An implementation is available in ProM and promising results have been obtained.Peer ReviewedPostprint (author's final draft