71 research outputs found

    20-SIM code generation for PC/104 target

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    From version 3.2, 20-Sim will contain a new tool, called C-code generation. With this tool it will be possible to generate C code from a 20-Sim model. This tool works on basis of templates. For each target, a target specific template has to be made.\ud The goal of this project was to write a new 20-Sim template for a PC/104 target, a embedded Intel 80486 pc on the mobile robot Arty. It should to be possible to control the robot with a 20-Sim model. The template had to be written using the Phar Lap TNT Toolsuite Lite, a toolsuite for real-time embedded development. The written template is working and to demonstrate this, a 20-Sim model that controls the robot is made.\ud Another goal of this project was testing the code generation tool and doing some recommendations for improvement. From this project it followed that this tool works good, but that the following points have to be improved:\ud · Controlling the target hardware from a 20-Sim model is possible but only via a time-consuming workaround route.\ud · The generated code is large, because it contains many not-used functions and redundant variables and equations.\ud · The Runge Kutta routines fail to work in the existing templates when a model has no states

    Concurrent Design of Embedded Control Software

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    Embedded software design for mechatronic systems is becoming an increasingly time-consuming and error-prone task. In order to cope with the heterogeneity and complexity, a systematic model-driven design approach is needed, where several parts of the system can be designed concurrently. There is however a trade-off between concurrency efficiency and integration efficiency. In this paper, we present a case study on the development of the embedded control software for a real-world mechatronic system in order to evaluate how we can integrate concurrent and largely independent designed embedded system software parts in an efficient way. The case study was executed using our embedded control system design methodology which employs a concurrent systematic model-based design approach that ensures a concurrent design process, while it still allows a fast integration phase by using automatic code synthesis. The result was a predictable concurrently designed embedded software realization with a short integration time

    GnRH - a Missing Link between Testosterone Concentrations in Yolk and Plasma and Its Intergenerational Effects

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    Despite the strong interest in hormone-mediated maternal effects two key questions concerning their mechanisms are as yet unanswered: First, whether the deposition of hormones in the egg yolk is coupled with the levels of these hormones in the maternal circulation, and second, whether epigenetic changes as induced by embryonic exposure to maternal yolk hormones impinge on yolk hormone deposition at adulthood. We investigated the responsiveness to gonadotropin-releasing hormone (GnRH) in female canaries whose embryonic exposure to yolk testosterone had been manipulated. This enabled us to study to what extent GnRH interlinks testosterone concentrations in female circulation and egg yolk as well as the intergenerational potential of hormone-mediated maternal effects. As expected, canary females responded to GnRH with a rise in plasma testosterone. The GnRH-responsiveness was positively correlated with the yolk testosterone content. Factors stimulating the release of GnRH will, therefore, lead to an increase of testosterone in both plasma and egg, posing a potential constraint on the yolk hormone deposition due to testosterone related trade-offs within the laying female. Exposure to elevated yolk testosterone levels as embryo reduced the GnRH-responsiveness in adulthood, potentially limiting environmental influences on yolk testosterone deposition, but the concentrations of yolk testosterone itself were not affected

    Communicating Process Architectures

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    Abstract. Most motion control systems for mechatronic systems are implemented on digital computers. In this paper we present an FPGA based solution implemented on a low cost Xilinx Spartan III FPGA. A Production Cell setup with multiple parallel operating units is chosen as a test case. The embedded control software for this system is designed in gCSP using a reusable layered CSP based software structure. gCSP is extended with automatic Handel-C code generation for configuring the FPGA. Many motion control systems use floating point calculations for the loop controllers. Low cost general purpose FPGAs do not implement hardware-based floating point units. The loop controllers for this system are converted from floating point to integer based calculations using a stepwise refinement approach. The result is a complete FPGA based motion control system with better performance figures than previous CPU based implementations

    Exploration speed in captivity predicts foraging tactics and diet in free-living red knots

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    1. Variation in foraging tactics and diet is usually attributed to differences in morphology, experience and prey availability. Recently, consistent individual differences in behaviour (personality) have been shown to be associated with foraging strategies. Bolder or more exploratory individuals are predicted to have a faster pace‐of‐life and offset the costs of moving more or in risky areas, with higher energetic gains by encountering profitable foraging opportunities and prey. However, the relationship between personality, foraging and diet is poorly understood. 2. We investigated how exploratory behaviour in red knots Calidris canutus is associated with foraging tactics and diet by combining laboratory experiments, field observations and stable isotope analysis. First, we developed a mobile experimental arena to measure exploration speed in controlled settings. We validated the method by repeated testing of individuals over time and contexts. This setup allowed us to measure exploratory personality at the field site, eliminating the need to bring birds into captivity for long periods of time. After releasing birds within days of their capture, we asked whether exploration speed was associated with differences in foraging tactics and diet in the wild. 3. We found that tactile foraging red knots mainly caught hard‐shelled prey that are buried in the sediment, whereas visual foraging knots only captured soft preys located close to or on the surface. We also found that faster explorers showed a higher percentage of visual foraging than slower explorers. By contrast, morphology (bill length and gizzard size) had no significant effect on foraging tactics. Diet analysis based on δ(15)N and δ(13)C stable isotope values of plasma and red blood cells confirmed our field observations with slower explorers mainly consumed hard‐shelled prey while faster explorers consumed more soft than hard‐shelled prey. 4. Our results show that foraging tactics and diet are associated with a personality trait, independent of morphological differences. We discuss how consistent behaviour might develop early in life through positive feedbacks between foraging tactics, prey type and foraging efficiency

    Effects of experimentally sustained elevated testosterone on incubation behaviour and reproductive success in female great tits (Pants major)

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    n many seasonally breeding birds, female and male testosterone (T) levels peak at the start of the breeding season, coinciding with pair bonding and nesting activities. Shortly after the onset of egg laying, T levels slowly decline to baseline levels in both sexes, but more rapidly so in females. During this period, T in males may still function to facilitate territorial behaviour, mate guarding and extra pair copulations, either via short lasting peaks or elevated basal levels of the hormone. In some species, however, males become insensitive to increased T after the onset of egg laying. It has been postulated that in these species bi-parental care is essential for offspring survival, as T is known to inhibit paternal care. However, only very few studies have analysed this for females. As females are heavily involved in parental care, they too might become insensitive to T after egg laying. Alternatively, because territorial defence, mate guarding and extra pair copulations are expected to be less important for females than for males, they may not have had the need to evolve a mechanism to become insensitive to T during the period of maternal care, because their natural T levels are never elevated during this part of the breeding season anyway. We tested these alternative hypotheses in female great tits (Parus major). Male great tits have previously been shown to be insensitive to T after egg laying with regard to nestling feeding behaviour (but not song rate). When females had started nest building, we experimentally elevated their T levels up to the nestling feeding phase, and measured incubation behaviour (only females incubate) and reproductive success. T did not significantly affect nest building or egg laying behaviour, although egg laying tended to be delayed in T females. Females with experimentally enhanced T maintained lower temperature during incubation but did not spend less time incubating. This might explain the reduced hatching success of their eggs, smaller brood size and lower number of fledglings we found in this study. As in this species T-dependent behaviour by females during the phase of parental care is not needed, the results support the hypothesis that in this species the need for selection in favour of T-insensitivity did not occur

    Comparative analysis of the human hepatic and adipose tissue transcriptomes during LPS-induced inflammation leads to the identification of differential biological pathways and candidate biomarkers

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    <p>Abstract</p> <p>Background</p> <p>Insulin resistance (IR) is accompanied by chronic low grade systemic inflammation, obesity, and deregulation of total body energy homeostasis. We induced inflammation in adipose and liver tissues <it>in vitro </it>in order to mimic inflammation <it>in vivo </it>with the aim to identify tissue-specific processes implicated in IR and to find biomarkers indicative for tissue-specific IR.</p> <p>Methods</p> <p>Human adipose and liver tissues were cultured in the absence or presence of LPS and DNA Microarray Technology was applied for their transcriptome analysis. Gene Ontology (GO), gene functional analysis, and prediction of genes encoding for secretome were performed using publicly available bioinformatics tools (DAVID, STRING, SecretomeP). The transcriptome data were validated by proteomics analysis of the inflamed adipose tissue secretome.</p> <p>Results</p> <p>LPS treatment significantly affected 667 and 483 genes in adipose and liver tissues respectively. The GO analysis revealed that during inflammation adipose tissue, compared to liver tissue, had more significantly upregulated genes, GO terms, and functional clusters related to inflammation and angiogenesis. The secretome prediction led to identification of 399 and 236 genes in adipose and liver tissue respectively. The secretomes of both tissues shared 66 genes and the remaining genes were the differential candidate biomarkers indicative for inflamed adipose or liver tissue. The transcriptome data of the inflamed adipose tissue secretome showed excellent correlation with the proteomics data.</p> <p>Conclusions</p> <p>The higher number of altered proinflammatory genes, GO processes, and genes encoding for secretome during inflammation in adipose tissue compared to liver tissue, suggests that adipose tissue is the major organ contributing to the development of systemic inflammation observed in IR. The identified tissue-specific functional clusters and biomarkers might be used in a strategy for the development of tissue-targeted treatment of insulin resistance in patients.</p
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