362 research outputs found
Making a Living between Crises and Ceremonies in Tana Toraja
Making a Living between Crisis and Ceremonies offers an account on the practice of everyday life of the Torajan people both in the highlands of Tana Toraja (South Sulawesi, Indonesia) and elsewhere (Makassar, Jakarta, Maleisië).; Readership: All concerned with the fields of livelihoods, migration, transnationalism, decentralization, economic crisis, and anyone interested in an ethnography of a Southeast Asian highland community: the Toraja
G23 peptide-mediated delivery of biodegradable nanocarriers across an in vitro blood-brain barrier model
The blood-brain barrier (BBB) consists of brain endothelial cells that prevent the passage of potentially harmful compounds from the blood into the brain. As a consequence, the BBB greatly hampers the treatment of brain diseases by limiting the entry of therapeutics into the brain. The effective treatment of brain diseases is further precluded by the enzymatic degradation of therapeutic molecules in the blood. Applying polymersomes for the transport of a therapeutic agent across the BBB seems a promising strategy for its delivery to the brain. Drugs can be encapsulated in these spherical nanoparticles composed of polymers in order to protect the therapeutics from degradation during circulation in the blood. The surface of polymersomes can be decorated with a ligand that stimulates the uptake of the drug-loaded nanoparticle by brain endothelial cells. This thesis described the design of biodegradable polymersomes that were decorated with the G23 peptide, which is a ligand that was shown to promote the transport of different types of nanoparticles across the BBB. A filter-free BBB model was developed in order to demonstrate the distinctive capacity of the G23 peptide to transport the biodegradable polymersomes across the BBB. The results of this study suggest that G23 polymersomes have the potential to become nanocarriers that enable effective treatment of brain diseases
On the complexity of hierarchical problem solving
Competent Genetic Algorithms can efficiently address problems in which the linkage between variables is limited to a small order k. Problems with higher order dependencies can only be addressed efficiently if further problem properties exist that can be exploited. An important class of problems for which this occurs is that of hierarchical problems. Hierarchical problems can contain dependencies between all variables (k = n) while being solvable in polynomial time. An open question so far is what precise properties a hierarchical problem must possess in order to be solvable efficiently. We study this question by investigating several features of hierarchical problems and determining their effect on computational complexity, both analytically and empirically. The analyses are based on the Hierarchical Genetic Algorithm (HGA), which is developed as part of this work. The HGA is tested on ranges of hierarchical problems, produced by a generator for hierarchical problems
Making a Living between Crises and Ceremonies in Tana Toraja
Making a Living between Crisis and Ceremonies offers an account on the practice of everyday life of the Torajan people both in the highlands of Tana Toraja (South Sulawesi, Indonesia) and elsewhere (Makassar, Jakarta, Maleisië).; Readership: All concerned with the fields of livelihoods, migration, transnationalism, decentralization, economic crisis, and anyone interested in an ethnography of a Southeast Asian highland community: the Toraja
Sparse signal processing on estimation grid with constant information distance applied in radar
Radar obtains its parameters on a grid whose design supports resolution of underlying radar processing. Existing radar exploits a regular grid although the resolution changes with stronger echoes at shorter ranges. We compute the radar resolution from the intrinsic geometrical structure of data models that is characterized in terms of the Fisher information metric. Based on the information-based approach, we design an estimation grid whose cells have a constant Fisher information distance. In addition, we explore how this information-based grid can suit radar processing in practice and propose information-based processing on such an irregular estimation grid by applying the sparse signal processing from compressive sensing. Accordingly, the grid was adjusted to the sensing incoherence needed in sparse signal processing by setting a lower bound for the cell size. Our approach enables an adaptive estimation grid that can be adjusted with respect to the available resolution, the desired sensing incoherence, available computational power, and required operational priorities. The information-based design and processing are illustrated in a one-dimensional case of range estimation
The dependence on temperature and salinity of dissolved
Recurring latitudinal patterns of the dissolved inorganic carbon (DIC) content and the fugacity of CO2 (fCO2) were observed in East Atlantic surface waters with strong gradients at hydrographic fronts. The dissolved inorganic carbon chemistry clearly displayed the effects of oceanic circulation and of persistent surface water processes. In two cases inorganic carbon components could be used as an indicator of the origin of hydrographic features. Surface water fCO2 below the atmospheric value, low DIC and low salinity north of the equator were ascribed to a combination of high rainfall and low wind speed in the Intertropical Convergence Zone and of biological uptake of CO2. Low surface water DIC and salinity delineated the Congo outflow. Along the cruise tracks calculated titration alkalinity (TA) had an almost linear relationship with salinity, while DIC had an apparent dependence on temperature and salinity. The latter dependence was tested by comparing observed DIC to DIC estimated from fCO2 and a reference value of TA normalised to salinity. Different scenarios of temperature, salinity, fCO2 and nutrient contents were applied. Changes of DIC were found to be indeed related to both temperature and salinity. The latitudinal distribution of DIC could be inferred with an accuracy of 17 μmol kg−1 and a standard deviation of 13 μmol kg−1 from in situ salinity, in situ temperature and the reference values of TA and nutrient contents normalised to in situ salinity (scenario D). The applied technique of estimating DIC from temperature and salinity is a powerful diagnostic tool to evaluate the spatial distribution of DIC.
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