Hochschule Bonn-Rhein-Sieg
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Phenotypic expansion of the BPTF-related neurodevelopmental disorder with dysmorphic facies and distal limb anomalies
No full textNeurodevelopmental disorder with dysmorphic facies and distal limb anomalies (NEDDFL), defined primarily by developmental delay/intellectual disability, speech delay, postnatal microcephaly, and dysmorphic features, is a syndrome resulting from heterozygous variants in the dosage-sensitive bromodomain PHD finger chromatin remodeler transcription factor BPTF gene. To date, only 11 individuals with NEDDFL due to de novo BPTF variants have been described. To expand the NEDDFL phenotypic spectrum, we describe the clinical features in 25 novel individuals with 20 distinct, clinically relevant variants in BPTF, including four individuals with inherited changes in BPTF. In addition to the previously described features, individuals in this cohort exhibited mild brain abnormalities, seizures, scoliosis, and a variety of ophthalmologic complications. These results further support the broad and multi-faceted complications due to haploinsufficiency of BPTF
Photonic NO2 Gas Sensing with Binaphthyl‐Based Dopants
No full textA series of reactive binaphthyl‐diimine‐based dopants is prepared and investigated with respect to their potential for the chiral induction of structural coloration in nematic liquid crystal mixture E7 and the selective photonic sensing of nitrogen dioxide (NO2). Studies of the helical twisting power (HTP) in 4‐cyano‐4′‐pentylbiphenyl (5CB) reveal HTP values as high as 375 µm‐1 and the tremendous impact of structural compatibility and changes of the dihedral binaphthyl angle on the efficiency of the chiral transfer. Detailed investigation of the sensing capabilities of the systems reveals an extraordinarily high selectivity for NO2 and a response to concentrations as low as 100 ppm. The systems show a direct response to the analyte gas leading to a concentration‐dependent shift of the reflectance wavelength of up to several hundred nanometers. Incorporation of copper ions remarkably improves the sensor's properties in terms of sensitivity and selectivity, enabling the tailored tweaking of the system's properties
Universities, Entrepreneurship and Enterprise Development in Africa – Conference Proceedings 2020: International Conference
No full textThese proceedings are the outcome of the 8th annual joint conference on "Universities Entrepreneurship and Enterprise Development in Africa" between the University of Cape Coast, Ghana and Hochschule Bonn-Rhein-Sieg University of Applied Sciences, Germany, held on 19-20 February 2020 on Campus Sankt Augustin, Hochschule Bonn-Rhein-Sieg University of Applied Sciences
Africa Aviation: Challenges and Opportunities
No full textThis study sought to apply the Structure Conduct Performance paradigm to Africa´s air transport landscape in general. To do that, it examines the past, present, and future expectations of four of Sub-Saharan Africa’s biggest aviation economies, namely South Africa, Kenya, Ethiopia, and Nigeria. Secondary data containing historical passenger traffic was analysed, and predictions for growth in the next ten years were proposed. The findings suggest that the experience of the existing liberalization initiatives, such as the Yamoussoukro Declaration (YD), has produced less than expected benefits. However, the future of aviation in Africa is somewhat positive, with a growth trajectory expected to follow a linear and gradual path supported by various initiatives, including the Single African Air Transport Market (SAATM) and the African Continental Free Trade Area (AFCTA). The study’s contribution is to illuminate the current discourse on the aviation sector in Africa through the Structure-Conduct-Performance theory paradigm and suggests a conceptual model that could be applied to future studies relating to aviation in Africa
The Role of Social Entrepreneurship in Achieving Sustainable Rural Development
No full textRural Social Entrepreneurship (RSE) is considered an essential factor for achieving Sustainable Rural Development (SRD) and improving rural people's socio-economic status through increasing production, productivity, reducing unemployment, and accelerating the progress in achieving SDGs. The paper aims at examining the role of social entrepreneurship in achieving (SRD) in Sudan with reference to Wad Balal Project for investment and rural development in Gezira State, which established in 2005 in small villages in Gezira State through mobilizing of local savings and resources for creating job opportunities, sponsoring poor households, improving the infrastructures, and reducing poverty. The study depends on cross-sectional data collected through a questionnaire and focus group discussion from 100 head of households in the village under research. A questionnaire is internally consistent, and its questions are stable. Frequencies and percentages have been used for describing the basic characteristics of the respondents. Statistical t-test was adopted to test the opinions of respondents about the role of the project based on the Likert scale. The results revealed that the project has significantly increased the opportunities of job and training as well as household income, the results also confirmed that the project has improved the status of education and health services in the village. The project has extended and established many branches; the project also diversified its investment to cover more kinds of investments, the project reinvested 50% of its profits and directed the rest to charity, and social services in the village, many lessons can be learned from the project story. The research recommended that a similar social entrepreneurship project can be generalized to more villages in Sudan and other developing countries to accelerate sustainable rural development. Local communities have to support similar initiatives for developing their villages
Fast and interactive ray-based rendering
No full textDespite their age, ray-based rendering methods are still a very active field of research with many challenges when it comes to interactive visualization. In this thesis, we present our work on Guided High-Quality Rendering, Foveated Ray Tracing for Head Mounted Displays and Hash-based Hierarchical Caching and Layered Filtering. Our system for Guided High-Quality Rendering allows for guiding the sampling rate of ray-based rendering methods by a user-specified Region of Interest (RoI). We propose two interaction methods for setting such an RoI when using a large display system and a desktop display, respectively. This makes it possible to compute images with a heterogeneous sample distribution across the image plane. Using such a non-uniform sample distribution, the rendering performance inside the RoI can be significantly improved in order to judge specific image features. However, a modified scheduling method is required to achieve sufficient performance. To solve this issue, we developed a scheduling method based on sparse matrix compression, which has shown significant improvements in our benchmarks. By filtering the sparsely sampled image appropriately, large brightness variations in areas outside the RoI are avoided and the overall image brightness is similar to the ground truth early in the rendering process. When using ray-based methods in a VR environment on head-mounted display de vices, it is crucial to provide sufficient frame rates in order to reduce motion sickness. This is a challenging task when moving through highly complex environments and the full image has to be rendered for each frame. With our foveated rendering sys tem, we provide a perception-based method for adjusting the sample density to the user’s gaze, measured with an eye tracker integrated into the HMD. In order to avoid disturbances through visual artifacts from low sampling rates, we introduce a reprojection-based rendering pipeline that allows for fast rendering and temporal accumulation of the sparsely placed samples. In our user study, we analyse the im pact our system has on visual quality. We then take a closer look at the recorded eye tracking data in order to determine tracking accuracy and connections between different fixation modes and perceived quality, leading to surprising insights. For previewing global illumination of a scene interactively by allowing for free scene exploration, we present a hash-based caching system. Building upon the concept of linkless octrees, which allow for constant-time queries of spatial data, our frame work is suited for rendering such previews of static scenes. Non-diffuse surfaces are supported by our hybrid reconstruction approach that allows for the visualization of view-dependent effects. In addition to our caching and reconstruction technique, we introduce a novel layered filtering framework, acting as a hybrid method between path space and image space filtering, that allows for the high-quality denoising of non-diffuse materials. Also, being designed as a framework instead of a concrete filtering method, it is possible to adapt most available denoising methods to our layered approach instead of relying only on the filtering of primary hitpoints
