Refine
Document Type
- Bachelor Thesis (41) (remove)
Language
- English (41) (remove)
Keywords
- Videospiel (4)
- Blockchain (3)
- Softwareentwicklung (3)
- Algorithmus (2)
- Bildgebendes Verfahren (2)
- Bildverarbeitung (2)
- Biomedizin (2)
- Biotechnologie (2)
- Graphentheorie (2)
- Künstliche Intelligenz (2)
Institute
- Angewandte Computer‐ und Biowissenschaften (41) (remove)
The loss of photoreceptors is a major course for visual impairment and blindness with no cure currently established. Photoreceptor replacement into mouse models of retinal degeneration is currently investigated as a potential future therapy. To evaluate visual function in mice before and after treatment two vision-based behavioral tests (optomotor tracking and the light/dark box) were investigated including their feasibility to distinguish between rod and cone photoreceptor function. Both methods turned out to be an objective and reliable readout for vision ability in wildtype mice and mice with vision impairment due to retinal degeneration. The capability of the methods to assess slight vision improvements have to be further evaluated.
Therefore options for improvement of the established tests and an idea for a new test paradigm have been introduced.
Genetic sex determination of ancient DNA samples based on one simple mathematical algorithm, which considers the number of mapped reads on autosomal, X, and Y chromosomes. The algorithm is implemented in one command line tool - SiD. SiD is used to deter-mine the sex of 16 samples, which have been shotgun sequenced and captured with a 1240k panel.
The following is a description and outline of the work done at the Cornell Lab of Ornithology developing Nation Feathers VR, a virtual reality game for learning about bird calls and songs. The goal was to develop a game which is intuitive, educational and entertaining. Furthermore, the software needed to be structured in a way that allows for feasible future expansion. This required careful data saving and retrieval. The game gives the player an opportunity to learn and apply that knowledge, all while maintaining a shorter runtime in order to reduce the total time spent in the virtual world. This is meant to prevent any discomfort to the player that may result from extended use of the VR headset.
Abstract nicht vorhanden
This thesis proposes a solution to the practical problem of supervising relatively basic mechanic processes in robotics by means of computervision. Supervision happens by comparing the tracked movement with a known, ideal recording of the movement that acts as a model.
First, this thesis analyzes possible approaches to the problem regarding data structures and representation, ways of extracting the data from the recording and ways to compare the data sets of two recordings. Then, a specific solution is implemented in C++ and explained.
The Blockchain is a technology which has the capabilities to change the way, the world operates. As promising as this may be, there are still many challenges which do not exist or are way simpler to solve in conventional software solutions. Services which are offered over the blockchain suffer from so called Block-confirmation-times where the customer simply has to wait till the transaction is confirmed. In this paper possible solutions to that problem will be examined and challenges that arise from the specific criteria of the Ethereum Blockchain will be analyzed.
Aminoacyl-tRNA synthetases (aaRSs) are key enzymes in the process of protein biosynthesis, charging tRNA molecules with their corresponding amino acid. Whereas adenosine phosphate fixation is common to all aaRSs, recognition of the respective amino acid to ensure correct translation poses a complex task, which is still not understood to its full extent. Using all aaRS structures in the Protein Data Bank (PDB), this thesis reveals further details about the specificitydetermining interactions of each aaRS. Moreover, inspection of the similarities between these enzymes using the structure-derived interaction data reinforces the sequence-based evolutionary trace of aaRSs to a certain degree: The concurrent development of two distinct Classes of aaRS is apparent at functional level, and previously determined evolutionary subclasses coincide altogether with specific aminoacyl recognition in each aaRS Type. Still, discrimination of amino acids in aaRSs involves a multitude of further relevant mechanisms. Eventually, analysis of specificity-relevant binding site interactions sheds light on how aaRS evolved to distinguish different amino acids.
In this work, the task is to cluster microarray gene expression data of the cyanobacterium Nostoc PCC 7120 for detection of messenger RNA (mRNA) degradation patterns. Searched are characteristic patterns of degradation which are caused by specific enzymes (ribonucleases) allowing a further biological investigation regarding biochemical mechanisms. The mRNA degradation is part of the regulation of gene expression because it regulates the amount and longevity of mRNA, which is available for translation into proteins. A particular class of RNA degrading enzymes are exoribonucleases which degrade the molecule from its ends, whereby a degradation from the 5’ end, the 3’ end or from both ends is theoretically possible.
In this investigation, the information about exoribonucleolytic degradation is given in a microarray data set containing gene expression values of 1,251 genes. The data set provides gene expression vectors containing the expression values of up to ten short distinct sections of a gene ordered from the genes 5’ end to its 3’ end. For each gene, expression vectors are available for both nitrogen fixing and non-nitrogen fixing conditions, which have to be considered separately due to biological reasons. Accordingly, after filtering and preprocessing, two datasets for clustering are obtained consisting of 133 ten-dimensional expression vectors. The similarity of the expression vectors is judged by a newly correlation based similarity measure and compared with the results obtained by use of the Euclidean distance. A non-linear transformation of the correlations was applied to obtain a dissimilarity measure. By choice of parameters within this transformation a user specific differentiation between negative and positive correlated gene expression vectors and an adequate adjustment regarding the noise level of gene expression values is possible.
Clustering was performed using Affinity Propagation (AP). The number of clusters obtained by AP depends on the so-called self-similarity for the data vectors. This dependence was used to identify stable cluster solutions by self-similarity control. To evaluate the clustering results, Median Fuzzy c-Means (M-FCM) was used. Further, several cluster validity measures are applied and visual inspections by t-distributed Stochastic Neighbor Embedding (t-SNE) as well as cluster visualization are provided for mathematical interpretation analysis of clusters.
To validate the clustering results biologically, the found data structure is checked for biological adequacy. A deeper investigation into the mechanisms behind mRNA-degradation was achieved by use of a RNA-Seq data set. Contained 40 (base pair) bp long reads for non-nitrogen fixing and nitrogen fixing conditions were assembled using bacteria-specific ab-initio assembly of Rockhopper. Thus, mRNA (transcript)-sequences of the clustered genes are obtained. A further investigation of the untranslated regions (UTRs) is performed here due to the assumption that exoribonucleases recognize specific transcript-sequences outside of the annotated gene regions as their binding sites. These UTRs need to be analyzed regarding sequence similarity using motif-finding algorithms.
In this work, we discuss the key role that “conflict minerals” (Gold, Coltan, Cobalt, Tin, Tungsten) play in global supply chains and high-technology industries, and the issues surrounding their extraction and trade in origin
countries, particularly in the African Congo Basin and the Great Lakes Region. We discuss ongoing international efforts to combat violence, child labour and human rights violations at mineral extraction areas, particularly in the Democratic Republic of the Congo (DRC), where very large mineral reserves have been discovered. We present the OECD Due Diligence Guidance for Responsible Supply Chains of Minerals from Conflict-Affected and High-Risk Areas, and the
GOTS MineralTrace mineral proof-of-origin and trade chain certification solution developed by ibes AG in Germany, which automates and simplifies the implementation of the OECD Guidance. We discuss a pilot project in DRC involving the GOTS GoldTrace application, based on the MineralTrace platform. We point out MineralTrace’s benefits and its limitations. We analyse possible solutions to said limitations, including an analysis of blockchain-based transactional information exchange and record keeping systems, and finally we propose a new MineralTrace Application Programming Interface (API) that solves current limitations, introduces configuration flexibility for client applications, introduces workflow flexibility to adapt MineralTrace to any country or region, and simplifies data export functionality.