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Decoding Fantasy Football : a Ludic Perspective
Full text linkFantasy sport has risen in popularity in the last decade with the advent of web 2.0. As people from around the world watch sporting events today, the internet has become an ideal site to instantly disseminate results and achievements for avid fans and followers. This paper is an attempt to position fantasy sports in the realm of game studies, drawing from the specific case of fantasy football (soccer in North America). Borrowing from and building on Roger Caillois classical game typology, this paper seeks to arrive at a nuanced understanding of both fantasy sport as a game and the experience it offers to participants. By using an ethnographic approach, based on in-depth interviews and co-playing sessions, this study closely observes participants in-game performances in the Fantasy Premier League. By stitching together information from the interviews with observation of participants approaches and preferences along with the performance of their teams, this paper identifies the key decisions and processes that a player of fantasy sport is part of. By situating fantasy sport in the ludic debate of preparation versus luck, this paper offers unique insights into the various ways that players exert effort to succeed at the game. The use of an approach that examines what players do to their fantasy teams enables this paper to examine players psyches and the interrelated elements of fandom, favoritism and loyalty. Analysis of the data offers insights in to the various practices and approaches of players as well as lays the foundation of new concept
Historical Development of Heavy Metal Input into Near-Coastal Areas : Reconstruction, Assessment & Ecological Response
Full text linkAnthropogenic influences on coastal marine ecosystems can date back several centuries or even millennia, however, with severely increasing impacts following the onset of the industrial revolution. Of particular interest is the release of contaminants, such as heavy metals, as they can have adverse effects on marine ecosystems. Monitoring programs record levels of heavy metals in coastal areas in order to assess the current degree of pollution and state of ecosystem health. To quantify the anthropogenic impact, heavy metal contents need to be compared to their naturally occurring background values. Near-coastal sediment cores have the potential to provide high-resolution archives to determine pristine background values, reconstruct the pollution history in sediments and evaluate its ecotoxicological effects. Therefore, this dissertation unravels the pollution history and elucidates natural background values in three study areas, the Firth of Thames (New Zealand), the Helgoland Mud Area (SE North Sea) and the Skagerrak (NE North Sea)
Large Scale Detailed Mapping of Dengue Vector Breeding Sites Using Street View Images
Full text linkTargeted environmental and ecosystem management remain crucial in control of dengue. But providing detailed environmental information on a large scale to effectively target dengue control efforts remains a challenge. In this paper we present the design and implementation of a pipeline to detect potential dengue vector breeding sites from geotagged images to create highly detailed container density maps at unprecedented scale. We implement the approach using Google Street View images which have the advantage of broad coverage and of being somewhat historical so that the data can be aligned with other types of data for analysis. Containers comprising eight of the most common breeding sites are detected in the images using convolutional neural network transfer learning. Over a test set of images the object recognition algorithm has an accuracy of 0.91 in terms of F-score. Container density counts are generated and displayed on a decision support dashboard. Extensive analyses of the approach is carried out over three provinces in Thailand. Results show that the container density counts agree well with manual container counts, with larval survey data, and with dengue case data. To delineate conditions under which the density counts are indicative of risk, a number of factors affecting agreement with larval survey and dengue case data are analyzed. We conclude that creation of container density maps from geotagged images is a promising approach to providing detailed risk maps at large scale. Ultimately, we intended to include our newly proposed index in the identification of dengue high-risk areas in Thailand
Automated analysis of necrosis and steatosis in histological images : Practical solutions for coping with heterogeneity and variability
Full text linkPathological examination of histological tissue sections is essential for the diagnosis of many life-threatening diseases. Demographic change and the growing importance of precision medicine require pathology to become more efficient, reproducible and quantitative. Automated histological image analysis is an important tool to meet these demands. This thesis is based on five research papers that consider specific problems in histological image analysis. The problems are related either to the quantification of necrosis or to the quantification of steatosis in histological sections of liver tissue. Both are typical applications in which tissue structures or cellular structures must be identified and quantitatively analyzed. In this context, the papers address important general challenges in histological image analysis and present broadly applicable solutions. One challenge is spatial heterogeneity of tissue properties, which can make their quantification sensitive to tissue sampling and image analysis errors. As a solution, the papers present novel scores that enable reliable measurement of heterogeneously distributed tissue properties. Another challenge is the huge variability of histological images, which can make machine learning-based analysis methods require large amounts of training data to work robustly. As a solution, the papers show how interactive training can produce accurate results with little training effort. Finally, a practical challenge is achieving a good trade-off between accuracy, efficiency, and simplicity. In this regard, the papers describe pragmatic approaches to enable accurate and fast analysis of gigapixel images on standard computers
Detailed analysis of MAX-DOAS measurements in Bremen : spatial and temporal distribution of aerosols, formaldehyde and nitrogen dioxide
Full text linkIn this thesis, spatial and temporal tropospheric inhomogeneities in the distribution of nitrogen dioxide (NO2), formaldehyde (HCHO) and aerosols are investigated. The analysis was done on a three years dataset (2015 - 2017) of ground-based multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurements in Bremen. MAX-DOAS measurements were investigated in three different azimuthal viewing directions in order to analyse lateral changes in the distribution of NO2 and HCHO in Bremen. A clear seasonality was found and explained by anthropogenic and biogenic emissions for NO2 and HCHO, respectively. While no significant azimuthal variability for HCHO was found, NO2 differs strongly for the westerly and southerly directions due to lateral inhomogeneities and a more frequent pointing towards the sun which has a strong impact on the results. In order to localize possible dominant emission sources of NO2 within the area of Bremen, the onion peeling approach was successfully applied by usage of the three fitting windows in the ultra-violet (UV) and visible (vis) spectral range. Strong emitters could be identified having a large impact on average NO2 results. A major challenge for the analysis of trace gases in the troposphere is the usually insufficient knowledge of aerosols, which might have a large impact on spectroscopic measurements. The novel MAX-DOAS profiling algorithm BOREAS was developed and its accuracy is validated with the help of synthetic data as well as ancillary measurements of the CINDI-2 field campaign (Cabauw, the Netherlands, 2016). In contrast to other algorithms, BOREASa aerosol information are retrieved by minimizing the difference of O4 optical depths of measurements and forward modelling calculations. The resulting aerosol extinction coefficient profiles were used for the retrieval of vertical trace gas concentration profiles. In this thesis, several retrieval modes and various ways of improving the regularization between measurement and a priori constraints as well as the selection of proper a priori profiles by use of a priori pre-scaling were investigated. The BOREAS algorithm was finally applied to the full MAX-DOAS dataset, and three years of aerosol and trace gas vertical profiles from the measurement location Bremen are presented and discussed with the help of in-situ as well as AERONET measurements. Seasonal, weekday and diurnal cycles for aerosols and NO2 were found which could be attributed to near surface emissions mainly from traffic and power plants. The seasonal cycle of HCHO is found to be dominated by biogenic emissions in summer, in addition to a smaller fraction of anthropogenic emissions in winter. While NO2 and aerosols are mainly focussed in layers close to the surface, larger HCHO concentrations could also be observed in the complete planetary boundary layer showing the need for the analysis of vertical concentration profiles of trace gases in the troposphere
Kommissionierung - Eine Analyse von aktuellen Kommissionierverfahren unter besonderer Berücksichtigung ihrer Effizienz
Full text linkEntwurf und Implementierung von digitalen Fehlerkorrekturverfahren für Mixed-Signal-Frontend-Schaltungen
Full text linkVarious non-ideal effects as well as environmental influences can affect the transfer characteristics of analog microelectronic circuits. In order to reduce the consequences of these effects, additional circuitry or different compensation techniques are usually used. Unfortunately, most of these methods have several drawbacks. They significantly increase the design time and costs of the circuit and lead to a higher consumption of energy and chip area. For this reason, an innovative method of error detection and correction is developed in this work, which is based on digital calibration and particularly well suited for the application in mixed-signal systems. With this approach, the error correction is no longer performed by complex, analog compensation techniques but by additional digital signal processing. First of all, a suitable test signal is fed into the analog circuit to make different errors visible. Subsequently, the test signal is evaluated in the digital part of the system by adaptive filters and appropriate algorithms to determine the kind and size of present errors. This information is used afterwards to eliminate any errors from the test and the useful signal. With this procedure, the disadvantages of analog compensation methods are removed with only a low overhead on digital circuitry. Furthermore, it is not only possible to correct static as well as time-variant errors but the circuit also gains the ability to monitor itself. As a result, the whole system becomes more reliable and robust. In order to demonstrate the performance of the introduced approach, it is used to correct different gain- and offset-errors in a generic sensor interface circuit. For this purpose, a simulation-based and a practical verification are performed to analyze various application and error cases. While a simulation model of the interface-circuit is used for the first task, a printed circuit board with electronic components is used for the second one. With both forms of verification, the successful application of the developed method can be shown
Carbohydrate-binding proteins from marine bacteria
No full textMarine phytoplankton is responsible for about half of the CO2 fixation on Earth. Algal photosynthesis results in the production of organic carbon, a substantial fraction of which is in the form of polysaccharides. Bacterial utilization of polysaccharides is a highly relevant process, which constitutes a major carbon and energy transfer in the ocean. Bacteroidetes, key marine polysaccharide degraders, are known to employ a complex protein system to bind, transport and digest polysaccharides. It was first characterized for the starch utilization system in Bacteroides thetaiotaomicron. In contrast to terrestrial or human gut microbes, polysaccharide degradation by marine bacteria remains largely unexplored. The main aim of my thesis was to investigate the molecular details of microbial polysaccharide utilization in the ocean. More specifically, during my Ph.D. thesis, I investigated carbohydrate-binding proteins involved in the recognition of substrates at the surface of bacterial cells. Based on the knowledge from homologous systems and bioinformatic predictions, we assumed that marine Bacteroidetes assemble outer membrane complexes composed of surface-glycan binding proteins to acquire polysaccharides. Previous experiments using fluorescently-labeled polysaccharides showed that marine Bacteroidetes take up polysaccharides in a selfish manner. These bacteria use surface-associated enzymes and binding proteins to partially degrade polysaccharides and minimize production of freely diffused hydrolysis products. For this approach, bacteria must have evolved a highly efficient and selective binding apparatus, which I studied in detail in this thesis. These in-depth analyses were necessary to evaluate the potential of carbohydrate-binding proteins as novel glycan probes. In the first manuscript, I present the characterization of GMSusD protein. We focused our analyses on proteins putatively specific to the highly abundant marine polysaccharide - laminarin. Biochemical and structural analyses on the GMSusD from Gramella sp. MAR 2010 102 revealed the predicted laminarin binding. Surprisingly, the protein was specific to a particular type of laminarin structure. There is a big discrepancy between vast a omicsa sequence data and functionally or structurally characterized proteins. To provide more accurate support for bioinformatic predictions we performed structure-guided alignment of metagenomes of global surface water datasets using the structure of GMSusD as a guide. We found SusD-like proteins with structurally conserved residues of the binding site in different locations in the ocean, suggesting a similar manner of laminarin recognition by these proteins. In the second manuscript, we identified two additional laminarin-binding proteins from the same planktonic bacteria. Upstream to the GMSusD, in the gene cluster called a Polysaccharide utilization locus, there were two genes encoded with previously unknown VI function. After excluding their enzymatic activity, we analyzed binding abilities. Based on the identified laminarin binding activity and predicted three-dimensional structures, we propose that these two proteins, GMSusE and GMSusF, belong to a highly unexplored group of SusEF- like binding proteins. Finally, I applied medium throughput expression of recombinant putative carbohydrate-binding proteins to investigate their potential as glycan probes. The field of marine glycobiology needs to be extended, since little is known about structures of polysaccharides present in the ocean. Thus, we proposed taking advantage of bacterial proteins, which are expressed in response to algal blooms in the North Sea. We investigated a library of forty-seven constructs resulting in the production of twelve soluble recombinant proteins, the binding of which was tested with environmental algal extracts and well-defined polysaccharide controls. These analyses allowed us to discover four novel carbohydrate- binding proteins specific to laminarin, a-mannan and b-mannan. However, we encountered some limitations of this approach, which are discussed in the third manuscript. The research performed in this thesis contributes to our greater quest to understand algal carbohydrate binding by marine microbes, which is a crucial mechanism for bacterial polysaccharide utilization and therefore key in the marine carbon cycle
Attention-dependent processing of motion in middle temporal area and striate cortex and its relation to behavioral detection speed
Full text linkThis cumulative thesis comprises of two published articles, a manuscript and two additional chapters serving as introduction and complementary section. In the reported studies the influence of covert attention onto the processing of motion in the middle temporal area and primary cortex of the macaque monkey brain is investigated. In the first part, evidence for a novel form of visual attention that is based on the class of the attended image properties is documented. In the second study a neural mechanism that is correlative of the subject's reaction time is identified and discussed. This findings deepen the insight on how oscillations of neural groups between brain areas interact and how this interaction might contribute to the observed reaction times. Finally an investigation that contributes to the analytical toolset needed for neuroscientific signal processing is reported
Design of a Biosensor for Detection of Bacteria in Water, by means of a Microfluidic System
No full textIn the context of the continuous growth of the worldwide population and the rapid ongoing urbanization around the globe, the need for affordable and effective systems to detect hazardous substances and pathogens in water has gained importance. In order to address this need, multi-disciplinary research efforts from the fields of micro-technology and micro-biology have led to the emergence of microfluidic devices in the form of Lab-on-a-Chip (LoC) and Micro Total Analysis (µTAS) devices, which are capable to host analytical and biorecognition assays, previously restricted to laboratory environments. Traditionally, the development of these devices had benefited from the microelectronics fabrication techniques, and afforded the replication of sub-micrometer channels and structures, as well as the implementation of functional materials to integrate diverse types of sensors (e.g. temperature, pressure, etc) in the same microfluidic device. Nevertheless, the reduction of the fabrication cost has become a persistent goal in order to popularize their utilization. This has urged the application of alternative materials like thermoplastics and large batch production techniques such as injection molding and hot embossing, at the same time to have set new challenges to their reliable and reproducible integration as analytical devices. The present report describes the design, development and testing of a microfluidic device for biosensing of bacteria, by means of RNA hybridization and fluorescence detection. The device consits in a fully Cyclo-Olefin Copolymer (COC) microfluidic chip, in size of 25,5 x 37,75 mm, structured by hot embossing. The microfluidic channels and cavities sum up a fluid volume of about 139 µL, comprising a heating chamber, temperature sensor chambers, cooling channel and reaction chamber. The device layout includes 7 inlets for the sample fluid and diverse reagents plus 1 outlet. On-chip assay starts with the intake of a volume of 1 mL of water sample. The sample fluid is pumped through the heater chamber, where heat from a screen printed heater is applied to lyse the bacteria and release their RNA content to the running flow. Following the same stream, the fluid with released RNA flows across the cooling channel until the reaction chamber. The reaction chamber bottom surface, previously functionalized with capture oligomers complementary to the RNA target sequences, hosts hybridization reactions to capture the target RNA. The captured RNA is later tagged with a fluorescence molecule in a second hybridization. After washing off unbound analytes, the overall fluorescence emission is collected, filtered and quantified. The net fluorescence intensity measurement is then interpreted as an indicator of the concentration of the viable bacteria presented in the sample. The microfluidic chip was tested in a custom testbench that included particle filtering and pre-concentration of bacteria from raw samples, and fluorescence detection system that performed a limit of detection of 18 fmol, with a sensitivity of 63,08 photon count per fmol. Theoretical evaluation of the microfluidic chip at 0,1 mL/min predicted a mass transport and heat transport efficiency of 68,57% and 67,27%, respectively. Experimentally, the microfluidic device in the biosensing system completed successful detection of bacteria from raw water in less than 1 hour. Fluorescence detection was completed from hybridized bacterial RNA, that was retrieved in the same chip by heat lysis on a dilution of 2x10^8 of E. coli. Theoretical limit of detection of 24,87x10^3 CFU/mL was calculated. The microfluidic chip, integrated with the fluorescence detection system, proved its functionality as biosensing system for on-site applications, as well as its potential as a reference of a low-cost, disposable device for real-time monitoring and control of bacteria pollution