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Multipath2.0: Extending Multilayer Reproducible Pathway Models with Omics Data
Full text linkBackground
Biological systems are often perceived as independent and consequently analyzed individually. In the field of omics, multiple disciplines target the study of specific types of molecules, such as genomics. The support of more data sources in these analyses is becoming more crucial for understanding the interplay of biological systems. However, this requires integration of heterogeneous knowledge, which is considered highly challenging in bioinformatics and biomedicine. Therefore, the R package Multipath was developed to model biological pathways as multilayered graphs and integrate influencing knowledge including proteins and drugs. In its previous form, Multipath generated multilayer models of BioPAX-encoded pathways and included features to integrate drug and protein information from DrugBank and UniProtKB respectively. Although the model showed remarkable utility, including further data sources ensures enriching and expanding its capabilities.
Results
In this paper, a new version Multipath 2.0 is presented. The update additionally supports the two databases KEGG Genes and OMIM, which serve as the source for gene and disease entries and interactions. Information on the interactions between the previously and newly added nodes are extracted and integrated. The Multipath 2.0 offers features to update the original multilayer model and integrate the corresponding nodes and edges into two additional layers referring to KEGG Genes and OMIM. Furthermore, the embedded nodes are inter- and intra-connected using interactions from the original and newly supported data sources.
Conclusion
The R Package Multipath is presented with the main functions that are newly developed to support the integration of the databases KEGG Genes and OMIM. The model comprises multiple information relevant to the analysis of pathway data, and offers a reproducible and simplified view of complex, intertwined systems. Through the application of such highly integrated models the inference of new knowledge becomes easier and contributes to many fields such as drug repurposing and biomarker discovery
Formelsammlung Wirtschaftsstatistik: Wissen kompakt für Studierende und Praktiker
No full textDiese etablierte Formelsammlung enthält und erklärt statistische Formeln, wie sie in den Wirtschaftswissenschaften und in der wirtschaftswissenschaftlichen Praxis fundamental notwendig sind. Das Verständnis der Formeln und deren praktische Anwendung werden durch nützliche Hilfen und verständliche Beispiele sinnvoll unterstützt, so dass der Kontext wirtschaftsstatistischer Formeln klar und allgemein verständlich erklärt dargestellt wird. Diese Formelsammlung ist ein unverzichtbares Tool für Studierende der Wirtschaftswissenschaften, aber auch ein nützliches Nachschlagewerk für Verantwortliche aus Wirtschaft, Politik und Lehre. In der 6. Auflage wurden die Inhalte überarbeitet und ergänzt
Statistics for Business and Economics: Compendium of Essential Formulas
No full textThis 3rd edition compendium contains and explains essential statistical formulae in an economic context. The compendium has been enhanced with numerous additional practical examples to help readers better understand the formulas and their practical applications. The statistical formulary is presented in a practical, clear and understandable manner, as required for meaningful and relevant application in global business as well as in academic and business practice. New content includes explanations on the use of so-called dummy variables, which are useful because of their operational relevance in practice, especially in financial statistics
Vierte Änderungsordnung vom 08.04.2025 der Geschäftsordnung des Hochschulrats der Hochschule Bonn-Rhein-Sieg vom 08.12.2022
Full text linkDevelopment, optimisation, and pre-validation of a gas chromatography—Ion mobility spectrometry method with preliminary twofold enrichment for the sensitive detection of N Nitrosamines in drinking water
Full text linkN-Nitrosamines have long been identified as a relevant contaminant in potable water due to their identification as probable human carcinogens. Thus, highly sensitive detection of these pollutants in the ultra-trace range is imperative to comply with strict regulatory specifications. To this end, many institutions rely on mass spectrometry-based analysis methods, which have the disadvantage of being cost- and resource intensive. This study aims to develop, optimise, and evaluate a gas chromatography-drift tube-ion mobility spectrometry (GCIMS) based method with a twofold enrichment strategy consisting of solid phase extraction (SPE) followed by intube extraction (ITEX) of the eluate for nine different nitrosamines in drinking water in order to offer a sensitive alternative to the current state of the art. Optimisation of ITEX parameters was successfully performed using a simplex self-directing design approach, so that a calibration range between 5 and 50 ng/L could be achieved. The suitability of a linear regression model was demonstrated via analysis of variance (ANOVA) criteria. The analysis of different spiked drinking water samples allowed for the determination of the method's accuracy (27.3 - 114.5 % across different nitrosamine analytes and matrices, with most above 70 % recovery) and detection limits (1.12 - 12.48 ng/L across different nitrosamine analytes and matrices), which fall within the range of required limit values. Tested drinking waters show innate nitrosamine concentrations well below detection limits and can thus be deemed free from contaminants
Design, Fabrication and Verification of Microoptics for Illumination Beamshaping in Active Imaging Systems
Full text linkActive 3D-imaging systems are increasingly important in fields such as logistics, biometric authentication, and industrial safety because they enable precise three-dimensional measurements. Unlike passive systems, they generate their own illumination, allowing these systems to perform measurements independently of ambient light. The active modulation of the illumination also makes it possible to obtain additional information. Active 3D imaging systems require the use of precise, efficient, and compact illumination components. In this work, existing illumination solutions are reviewed, with particular emphasis on two approaches: randomized microlens arrays (rMLAs) and computer-generated holograms (CGHs). A robust development process for the design, fabrication and validation of rMLAs and CGHs is presented and demonstrated using the design of diffusers for time-of-flight (ToF) cameras as an example. These diffusers convert the circular output of an uncollimated array of vertical-cavity surface-emitting lasers (VCSELs) into a rectangular beam profile with higher intensity at the edges, known as a batwing profile, to compensate for vignetting in the ToF camera. Vignetting describes the drop-off in illumination at the edges of the image. Two different target batwing profiles are selected, and for each one CGH and one rMLA is designed. In addition to these four state-of-the-art designs, four novel diffusers are designed, which incorporate a collimating lens in the original diffuser surface.
The designed diffusers are first validated through simulations, and subsequently fabricated using a two-photon polymerization 3D printer. The beam profiles generated by the manufactured diffusers, when illuminated with a VCSEL array, are then investigated using a camera-based beam profile measurement setup.
The efficiency with which the fabricated diffusers direct light into the desired region is up to 81 %. The diffusers correctly illuminate the intended rectangular field of illumination (FOI), although minor errors in the FOI size are observed. The cause of these errors is shown in simulations and can be avoided in future work. The proposed integrated collimation successfully results in sharper and more efficient beam profilesAktive 3D-Bildgebungssysteme gewinnen in Bereichen wie der Logistik, der biometrischen Authentifizierung und der industriellen Sicherheit zunehmend an Bedeutung, da sie präzise dreidimensionale Messungen ermöglichen. Im Gegensatz zu passiven Systemen erzeugen sie ihre eigene Beleuchtung, wodurch diese Systeme unabhängig vom Umgebungslicht Messungen durchführen können. Die aktive Modulation der Beleuchtung ermöglicht es außerdem zusätzliche Informationen zu gewinnen. Aktive 3D-Bildgebungssysteme erfordern dabei den Einsatz von präzisen, effizienten und kompakten Beleuchtungskomponenten.
In dieser Arbeit werden bestehende Beleuchtungslösungen untersucht, wobei der Schwerpunkt auf zwei Ansätzen liegt: randomisierte Mikrolinsenarrays (rMLAs) und computergenerierte Hologramme (CGHs). Ein robuster Entwicklungsablauf für das Design, die Herstellung und die Valdidierung von rMLAs und CGHs wird vorgestellt und beispielhaft am Design von Diffusoren für Time-of-Flight (ToF) Kameras demonstriert. Die Diffusoren sind so konzipiert, dass sie die kreisförmige Ausgangsstrahlung eines unkolimierten Arrays von oberflächenemittierenden Lasern (VCSEL) in ein rechteckiges Strahlprofil umwandeln.
Dieses Strahlprofil weißt eine erhöhte Intensität an den Rändern auf, um den Randlichtabfall von Objektiven auszugleichen, und wird gemeinhin als batwing Profil bezeichnet. Zwei verschiedene batwing Profile werden als Ziele definiert, und für jedes davon wird jeweils ein CGH und ein rMLA entworfen. Aufbauend auf diesen vier Designs werden zusätzlich vier neuartige Diffusoren entwickelt, die eine kollimierende Linse in die ursprüngliche Diffusoroberfläche integrieren.
Die entworfenen Diffusoren werden zunächst durch Simulationen validiert. Anschließend werden sie mittels Zwei-Photonen-Polymerisation in einem 3D-Druckverfahren hergestellt. Die durch die gefertigten Diffusoren erzeugten Strahlprofile werden dann, bei Beleuchtung mit einem VCSEL-Array, mit einem kamerabasierten Strahlprofilmesssystem gemessen.
Die Effizienz mit der die gefertigten Diffusoren das von der Lichtquelle abgestrahle Licht in den gewünschten Bereich leiten, liegt bei bis zu 81 %. Die Diffusoren beleuchten das gewünschte rechteckige Beleuchtungsfeld mit der angestrebten Intensitätsverteilung. Die vorgeschlagene integrierte Kollimation sorgt erfolgreich für schärfere und effizientere Strahlprofile. Die Gründe für verbleibende Fehler im Strahlprofil werden durch Simulationen aufgezeigt, und können zukünftig vermieden werden
