Data Mining in a Multidimensional Environment

Data Mining and Data Warehousing are two hot topics in the database research area. Until recently, conventional data mining algorithms were primarily developed for a relational environment. But a data warehouse database is based on a multidimensional model. In our paper we apply this basis for a seamless integration of data mining in the multidimensional model for the example of discovering association rules. Furthermore, we propose this method as a userguided technique because of the clear structure both of model and data. We present both the theoretical basis and efficient algorithms for data mining in the multidimensional data model. Our approach uses directly the requirements of dimensions, classifications and sparsity of the cube. Additionally we give heuristics for optimizing the search for rules

Benchmarking Big Data Technologies for Energy Procurement Efficiency

The electrical power industry is undergoing radical change due to the push for renewable energy that makes energy supply less predictable. Smart meters along with analytics software can grant insights into customer-specific consumption and thereby enable a better match between the demand and supply side for an electric utility. However, the vast amount of allocatable smart metering data and complexity of analytics pose challenges to database system. We address the implementation of an analytics ap-proach to optimize customer portfolios, eventually preventing excess energy procurement. Using real-world and simulated data, we test the suitability of big data approaches as well as traditional relational database technology. Furthermore, we present solutions based on big data platforms and demonstrate their cost effectiveness and performance. Our findings suggest economic feasibility of big data solutions for large utilities. Small and medium-sized utilities are advised to invest in more cost-effective solutions such as cluster-based systems

CIS: A Web-Based Course Information System

This report surveys the design and implementation of CIS, a web-based Course Information System. CIS has been developed for the Computer Science I/II courses held between 2000 and 2003 by Prof. Dr. R. Loos, which were attended by 300 to 450 students. It maintains and presents each student's submissions and grades and holds related information such as worksheet texts, submission deadlines and the assignment of students to teaching assistents. In short, it covers most of the administrative data that comes up in regular university courses. CIS is designed to be used by first-year students conveniently. It aims at modelling real-world procedures, so that the system behaviour can be explained in well-known analogies. It is minimalistic, in the sense that it only takes on the routine work, while leaving the teacher free in any questions of structuring the contents of the course. Our problem statement and analysis focuses to two aspects: The requirements on the central data base and the interfaces for three groups of users: Students, teaching assistants, and teachers/adminis-trators. The actual implementation is straightforward, and we only mention particular decisions taken herein. CIS has been in use at the Wilhelm-Schickard Institut for three years, in courses organized both by the authors and others. The experiences indicate that the system can be considered reliable and mature. As the effort of setting up CIS is small, it has become feasible to employ it for several advanced courses with fewer than 20 students

Rechtsextremismus: Digitale Hasskulturen und ihre Folgen

Wie verändert digitale Kommunikation den Rechtsextremismus? Zu den auffälligen Entwicklungen gehören zweifellos Hasskulturen, die sich über soziale Medien ausbreiten. Über sie formieren sich neue, virtuelle Allianzen, die rechtsextreme Ideologien und Gewaltrhetorik effektiv in die öffentliche Debatte transportieren. Hass und Hetze in den sozialen Medien gehen mit Gewalt und Terror in der realen Welt einher. Insbesondere im rechtsextremen Spektrum sind Akte der politischen Gewalt mit interaktiver Kommunikation im Internet verzahnt. Sie entspringen einer virtuellen Gemeinschaft, die mit ihren politischen Gegnern abrechnet - online und offline

Long-term psychodynamic psychotherapy in a face-to-face versus videoconferencing setting: A single case study.

OBJECTIVE Due to the coronavirus pandemic and crisis, psychotherapists around the world were forced to switch to video- or tele-based treatments overnight. To date, only a few studies on the effectiveness of video-based psychodynamic psychotherapy via the Internet exist. Therefore, the goal of the present study was to examine symptom improvement, therapeutic relationship, nonverbal synchrony processes, and intersession processes within a systematic single case design and compare face-to-face to video-based approaches in long-term psychodynamic-oriented psychotherapy. METHODS We examined 85 sessions of a client with major depression whose psychodynamic psychotherapy changed from a face-to-face setting to a video-based setting. Video recordings were analyzed using motion energy analysis, and nonverbal synchrony was computed using a surrogate synchrony approach. Time series analyses were performed to analyze changes in symptom severity, therapeutic relationship, and intersession processes. RESULTS The results showed that symptom severity improved descriptively, but not significantly, across the entire course of psychotherapy. There were significant differences, however, in the therapeutic relationship, intersession experiences, and synchronous behavior between the face-to-face and video-based settings. CONCLUSION The results indicate that the presented methodology is well situated to investigate the question whether psychodynamic psychotherapy in video-based setting works in the sameway as in a face-to-face setting

Who punishes the leader? Leader culpability and coups during civil war

Who punishes leaders via coups during civil war? By distinguishing between different types of internal audiences within the government and their attempts to remove a leader forcefully, I illuminate the mechanisms that explain variation in who punishes the leader during wartime. I claim that whether leaders are culpable for the initiation of the war has an important implication for whether they are punished by members of the ruling coalition (i.e., those with access to decision-making and political power), or by those outside the ruling coalition. Empirical evidence supports my hypotheses: (i) culpable leaders are more likely to experience coup attempts led by those outside the leaders' ruling coalition, should the war go poorly; and (ii) nonculpable leaders are more likely to experience coups executed by members of their ruling coalition. The findings have important implications for how leaders respond to audience pressures as they consider whether to fight or settle

Control of phase formation of (AlxGa1 - X)2O3thin films on c-plane Al2O3

In this paper, the growth of orthorhombic and monoclinic (Al x Ga1 - x )2O3 thin films on (00.1) Al2O3 by tin-assisted pulsed laser deposition is investigated as a function of oxygen pressure p(O2) and substrate temperature Tg. For certain growth conditions, defined by Tg = 580°C and p(O2) = 0.016 mbar, the orthorhombic ?-polymorph is stabilized. For Tg = 540°C and p(O2) = 0.016 mbar, the ?-, and the ß-, as well as the spinel ?-polymorph coexist, as illustrated by XRD 2?-?-scans. Further employed growth parameters result in thin films with a monoclinic ß-gallia structure. For all polymorphs, p(O2) and Tg affect the formation and desorption of volatile suboxides, and thereby the growth rate and the cation composition. For example, low oxygen pressures lead to low growth rates and enhanced Al incorporation. This facilitates the structural engineering of polymorphic, ternary (Al,Ga)2O3 via selection of the relevant process parameters. Transmission electron microscopy (TEM) studies of a ? - (Al0.13Ga0.87)2O3 thin film reveal a more complex picture compared to that derived from x-ray diffraction measurements. Furthermore, this study presents the possibility of controlling the phase formation, as well as the Al-content, of thin films based on the choice of their growth conditions. © 2020 The Author(s). Published by IOP Publishing Ltd

Ion channels in control of pancreatic stellate cell migration

Pancreatic stellate cells (PSCs) play a critical role in the progression of pancreatic ductal adenocarcinoma (PDAC). Once activated, PSCs support proliferation and metastasis of carcinoma cells. PSCs even co-metastasise with carcinoma cells. This requires the ability of PSCs to migrate. In recent years, it has been established that almost all “hallmarks of cancer” such as proliferation or migration/invasion also rely on the expression and function of ion channels. So far, there is only very limited information about the function of ion channels in PSCs. Yet, there is growing evidence that ion channels in stromal cells also contribute to tumor progression. Here we investigated the function of K(Ca)3.1 channels in PSCs. K(Ca)3.1 channels are also found in many tumor cells of different origin. We revealed the functional expression of K(Ca)3.1 channels by means of Western blot, immunofluorescence and patch clamp analysis. The impact of K(Ca)3.1 channel activity on PSC function was determined with live-cell imaging and by measuring the intracellular Ca2(+) concentration ([Ca(2+)](i)). K(Ca)3.1 channel blockade or knockout prevents the stimulation of PSC migration and chemotaxis by reducing the [Ca(2+)](i) and calpain activity. K(Ca)3.1 channels functionally cooperate with TRPC3 channels that are upregulated in PDAC stroma. Knockdown of TRPC3 channels largely abolishes the impact of K(Ca)3.1 channels on PSC migration. In summary, our results clearly show that ion channels are crucial players in PSC physiology and pathophysiology

Thin-film calorimetry: analytical tool for in-situ characterization of lithium ion batteries

Thin-Film Calorimetry (TFC) as presented in this work is a novel analytical tool to determine phase transformation temperatures and enthalpies of thin films and thin-film sequences. The key component is a high-temperature stable piezoelectric langasite (La3Ga5SiO14) resonator serving as a highly sensitive planar temperature sensor. Deviations in its frequency are related to temperature fluctuations caused by phase transformations and used to calculate the related enthalpies. Temperature ramps from room temperature up to 1000°C are applied to perform calorimetric thin-film investigations. Thereby, the atmosphere can be controlled. To the best of our knowledge, the presented TFC is the only existing technique combining the aspects “thin films” and “high-temperature calorimetry.” The first part of this article describes the newly developed TFC system. The second part presents TFC investigations on lithium manganese oxide (LMO) thin films. Measurements are carried out in ambient air and in 0.5 %H2/Ar. In air three phase transformations appear (at 330, 410 and 600°C) while in 0.5 %H2/Ar four phase transformations are observed (at 389, 471, 730 and 758°C). Their progression and related enthalpies are discussed. To determine the associated crystallographic phases, X-ray diffraction and Raman spectroscopy are performed

A Novel NHE1-Centered Signaling Cassette Drives Epidermal Growth Factor Receptor–Dependent Pancreatic Tumor Metastasis and Is a Target for Combination Therapy

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers principally because of early invasion and metastasis. The epidermal growth factor receptor (EGFR) is essential for PDAC development even in the presence of Kras, but its inhibition with erlotinib gives only a modest clinical response, making the discovery of novel EGFR targets of critical interest. Here, we revealed by mining a human pancreatic gene expression database that the metastasis promoter Na+/H+ exchanger (NHE1) associates with the EGFR in PDAC. In human PDAC cell lines, we confirmed that NHE1 drives both basal and EGF-stimulated three-dimensional growth and early invasion via invadopodial extracellular matrix digestion. EGF promoted the complexing of EGFR with NHE1 via the scaffolding protein Na +/H + exchanger regulatory factor 1, engaging EGFR in a negative transregulatory loop that controls the extent and duration of EGFR oncogenic signaling and stimulates NHE1. The specificity of NHE1 for growth or invasion depends on the segregation of the transient EGFR/Na +/H + exchanger regulatory factor 1/NHE1 signaling complex into dimeric subcomplexes in different lipid raftlike membrane domains. This signaling complex was also found in tumors developed in orthotopic mice. Importantly, the specific NHE1 inhibitor cariporide reduced both three-dimensional growth and invasion independently of PDAC subtype and synergistically sensitized these behaviors to low doses of erlotinib