1,044 research outputs found

    Gamification in factory management education : A case study with Lego Mindstorms

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    Research oriented teaching in universities provides opportunities to support the student's desire to explore. A student's learning success can benefit from gamified project work, especially when students face self-guided learning processes in demanding educational activities. Gamification is defined as the use of game elements in a non-game context. Games offer the chance to improve the motivation of students, support group work, train communication skills and introduce the capacity for experimenting in safe environments. Therefore the learning effect of prospective engineers can be increased through the integration of Gamification into educational activities. This leads to higher student participation in university courses and encourages the development of the student's social, personal and technical competences. In this paper a game concept for teaching in universities is introduced focusing on the impartment of the state of the art on manufacturing for value creation, e.g. production planning and control. The concept covers a level based storyline with rules and goals using physical artefacts of Lego Mindstorms. Due to the modular characteristic of Lego, which supports creativity by having a high number of possible combinations, a “free playing space” for students is established. In groups, the students work in a highly problem oriented way, e.g. finding cost savings for their factory due to a changing market condition. Feedback in the sense of the success of student's strategies is given directly through the designed Lego model and its functionality

    Procedure for Experiential Learning to Conduct Material Flow Simulation Projects, Enabled by Learning Factories

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    Material flow simulation is a powerful tool to identify improvements in factory operation. For conducting simulation projects, experts are required who know how to prepare, execute and evaluate simulation studies. To date, training mostly focusses on textual case studies, whereby learners perform simulation studies based on a problem and data given in a description. However, this hardly reflects the ways engineers learn. They are mostly used to physically experiment based on their experience. In this paper, a procedure for experiential learning to conduct material flow simulation projects is elaborated, enabled by learning factories. A learning situation at Vietnamese-German University is described. Results indicate, that the students gain particular awareness about the challenges associated with the abstraction of the reality and the interpretation of the simulation outcomes

    Language independent transfer of assembly knowledge

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    Transferring assembly knowledge for workers with different cultural and linguistic background is challenging. The established solution of translating written instructions into multiple languages is mostly cost intensive, holds a potential for mistakes and the result might be hard to understand. To cope with this challenge, three different assembly instructions with language reduced or language independent content have been tested in a study with students in Vietnam and Germany. The types of instructions were interactive 3D-PDF, Utility-Film and illustrated manual. Assembly errors, assembly time, safety symbol awareness and assembly sequences understanding are compared and evaluated based on students’ technical pre-knowledge and experience. The 3D-PDF showed to be the best solution to be applied in this complex environment, because users were able to assemble the parts faster and experienced a higher degree of interactivity compared to the other instructions

    Towards resolving Lamiales relationships: insights from rapidly evolving chloroplast sequences

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    <p>Abstract</p> <p>Background</p> <p>In the large angiosperm order Lamiales, a diverse array of highly specialized life strategies such as carnivory, parasitism, epiphytism, and desiccation tolerance occur, and some lineages possess drastically accelerated DNA substitutional rates or miniaturized genomes. However, understanding the evolution of these phenomena in the order, and clarifying borders of and relationships among lamialean families, has been hindered by largely unresolved trees in the past.</p> <p>Results</p> <p>Our analysis of the rapidly evolving <it>trnK/matK</it>, <it>trnL-F </it>and <it>rps16 </it>chloroplast regions enabled us to infer more precise phylogenetic hypotheses for the Lamiales. Relationships among the nine first-branching families in the Lamiales tree are now resolved with very strong support. Subsequent to Plocospermataceae, a clade consisting of Carlemanniaceae plus Oleaceae branches, followed by Tetrachondraceae and a newly inferred clade composed of Gesneriaceae plus Calceolariaceae, which is also supported by morphological characters. Plantaginaceae (incl. Gratioleae) and Scrophulariaceae are well separated in the backbone grade; Lamiaceae and Verbenaceae appear in distant clades, while the recently described Linderniaceae are confirmed to be monophyletic and in an isolated position.</p> <p>Conclusions</p> <p>Confidence about deep nodes of the Lamiales tree is an important step towards understanding the evolutionary diversification of a major clade of flowering plants. The degree of resolution obtained here now provides a first opportunity to discuss the evolution of morphological and biochemical traits in Lamiales. The multiple independent evolution of the carnivorous syndrome, once in Lentibulariaceae and a second time in Byblidaceae, is strongly supported by all analyses and topological tests. The evolution of selected morphological characters such as flower symmetry is discussed. The addition of further sequence data from introns and spacers holds promise to eventually obtain a fully resolved plastid tree of Lamiales.</p

    A closer look at the binary content of NGC 1850

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    Studies of young clusters have shown that a large fraction of O-/early B-type stars are in binary systems, where the binary fraction increases with mass. These massive stars are present in clusters of a few Myr, but gradually disappear for older clusters. The lack of detailed studies of intermediate-age clusters has meant that almost no information is available on the multiplicity properties of stars with M &lt; 4 M☉. In this study we present the first characterization of the binary content of NGC 1850, a 100 Myr-old massive star cluster in the Large Magellanic Cloud, relying on a VLT/MUSE multi-epoch spectroscopic campaign. By sampling stars down to M = 2.5 M☉, we derive a close binary fraction of 24 ± 5 per cent in NGC 1850, in good agreement with the multiplicity frequency predicted for stars of this mass range. We also find a trend with stellar mass (magnitude), with higher mass (brighter) stars having higher binary fractions. We modelled the radial velocity curves of individual binaries using THE JOKER and constrained the orbital properties of 27 systems, ∼17 per cent of all binaries with reliable radial velocities in NGC 1850. This study has brought to light a number of interesting objects, such as four binaries showing mass functions f(M) &gt; 1.25 M☉. One of these, star #47, has a peculiar spectrum, explainable with the presence of two discs in the system, around the visible star and the dark companion, which is a black hole candidate. These results confirm the importance and urgency of studying the binary content of clusters of any age.</p

    Concomitant Carcinoma in situ in Cystectomy Specimens Is Not Associated with Clinical Outcomes after Surgery

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    Objective: The aim of this study was to externally validate the prognostic value of concomitant urothelial carcinoma in situ (CIS) in radical cystectomy (RC) specimens using a large international cohort of bladder cancer patients. Methods: The records of 3,973 patients treated with RC and bilateral lymphadenectomy for urothelial carcinoma of the bladder (UCB) at nine centers worldwide were reviewed. Surgical specimens were evaluated by a genitourinary pathologist at each center. Uni- and multivariable Cox regression models addressed time to recurrence and cancer-specific mortality after RC. Results: 1,741 (43.8%) patients had concomitant CIS in their RC specimens. Concomitant CIS was more common in organ-confined UCB and was associated with lymphovascular invasion (p < 0.001). Concomitant CIS was not associated with either disease recurrence or cancer-specific death regardless of pathologic stage. The presence of concomitant CIS did not improve the predictive accuracy of standard predictors for either disease recurrence or cancer-specific death in any of the subgroups. Conclusions: We could not confirm the prognostic value of concomitant CIS in RC specimens. This, together with the discrepancy between pathologists in determining the presence of concomitant CIS at the morphologic level, limits the clinical utility of concomitant CIS in RC specimens for clinical decision-making. Copyright (C) 2011 S. Karger AG, Base

    Long non-coding RNAs defining major subtypes of B cell precursor acute lymphoblastic leukemia

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    BACKGROUND: Long non-coding RNAs (lncRNAs) have emerged as a novel class of RNA due to its diverse mechanism in cancer development and progression. However, the role and expression pattern of lncRNAs in molecular subtypes of B cell acute lymphoblastic leukemia (BCP-ALL) have not yet been investigated. Here, we assess to what extent lncRNA expression and DNA methylation is driving the progression of relapsed BCP-ALL subtypes and we determine if the expression and DNA methylation profile of lncRNAs correlates with established BCP-ALL subtypes. METHODS: We performed RNA sequencing and DNA methylation (Illumina Infinium microarray) of 40 diagnosis and 42 relapse samples from 45 BCP-ALL patients in a German cohort and quantified lncRNA expression. Unsupervised clustering was applied to ascertain and confirm that the lncRNA-based classification of the BCP-ALL molecular subtypes is present in both our cohort and an independent validation cohort of 47 patients. A differential expression and differential methylation analysis was applied to determine the subtype-specific, relapse-specific, and differentially methylated lncRNAs. Potential functions of subtype-specific lncRNAs were determined by using co-expression-based analysis on nearby (cis) and distally (trans) located protein-coding genes. RESULTS: Using an integrative Bioinformatics analysis, we developed a comprehensive catalog of 1235 aberrantly dysregulated BCP-ALL subtype-specific and 942 relapse-specific lncRNAs and the methylation profile of three subtypes of BCP-ALL. The 1235 subtype-specific lncRNA signature represented a similar classification of the molecular subtypes of BCP-ALL in the independent validation cohort. We identified a strong correlation between the DUX4-specific lncRNAs and genes involved in the activation of TGF-β and Hippo signaling pathways. Similarly, Ph-like-specific lncRNAs were correlated with genes involved in the activation of PI3K-AKT, mTOR, and JAK-STAT signaling pathways. Interestingly, the relapse-specific lncRNAs correlated with the activation of metabolic and signaling pathways. Finally, we found 23 promoter methylated lncRNAs epigenetically facilitating their expression levels. CONCLUSION: Here, we describe a set of subtype-specific and relapse-specific lncRNAs from three major BCP-ALL subtypes and define their potential functions and epigenetic regulation. The subtype-specific lncRNAs are reproducible and can effectively stratify BCP-ALL subtypes. Our data uncover the diverse mechanism of action of lncRNAs in BCP-ALL subtypes defining which lncRNAs are involved in the pathogenesis of disease and are relevant for the stratification of BCP-ALL subtypes

    Quantitative promoter methylation analysis of multiple cancer-related genes in renal cell tumors

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    <p>Abstract</p> <p>Background</p> <p>Aberrant promoter hypermethylation of cancer-associated genes occurs frequently during carcinogenesis and may serve as a cancer biomarker. In this study we aimed at defining a quantitative gene promoter methylation panel that might identify the most prevalent types of renal cell tumors.</p> <p>Methods</p> <p>A panel of 18 gene promoters was assessed by quantitative methylation-specific PCR (QMSP) in 85 primarily resected renal tumors representing the four major histologic subtypes (52 clear cell (ccRCC), 13 papillary (pRCC), 10 chromophobe (chRCC), and 10 oncocytomas) and 62 paired normal tissue samples. After genomic DNA isolation and sodium bisulfite modification, methylation levels were determined and correlated with standard clinicopathological parameters.</p> <p>Results</p> <p>Significant differences in methylation levels among the four subtypes of renal tumors were found for <it>CDH1 </it>(<it>p </it>= 0.0007), <it>PTGS2 </it>(<it>p </it>= 0.002), and <it>RASSF1A </it>(<it>p </it>= 0.0001). <it>CDH1 </it>hypermethylation levels were significantly higher in ccRCC compared to chRCC and oncocytoma (<it>p </it>= 0.00016 and <it>p </it>= 0.0034, respectively), whereas <it>PTGS2 </it>methylation levels were significantly higher in ccRCC compared to pRCC (<it>p </it>= 0.004). <it>RASSF1A </it>methylation levels were significantly higher in pRCC than in normal tissue (<it>p </it>= 0.035). In pRCC, <it>CDH1 </it>and <it>RASSF1A </it>methylation levels were inversely correlated with tumor stage (<it>p </it>= 0.031) and nuclear grade (<it>p </it>= 0.022), respectively.</p> <p>Conclusion</p> <p>The major subtypes of renal epithelial neoplasms display differential aberrant <it>CDH1</it>, <it>PTGS2</it>, and <it>RASSF1A </it>promoter methylation levels. This gene panel might contribute to a more accurate discrimination among common renal tumors, improving preoperative assessment and therapeutic decision-making in patients harboring suspicious renal masses.</p

    A Two-Dimensional Electron Gas as a Sensitive Detector for Time-Resolved Tunneling Measurements on Self-Assembled Quantum Dots

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    A two-dimensional electron gas (2DEG) situated nearby a single layer of self-assembled quantum dots (QDs) in an inverted high electron mobility transistor (HEMT) structure is used as a detector for time-resolved tunneling measurements. We demonstrate a strong influence of charged QDs on the conductance of the 2DEG which allows us to probe the tunneling dynamics between the 2DEG and the QDs time resolved. Measurements of hysteresis curves with different sweep times and real-time conductance measurements in combination with an boxcar-like evaluation method enables us to unambiguously identify the transients as tunneling events between the s- and p-electron QD states and the 2DEG and rule out defect-related transients
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