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A study was conducted to examine the use of three landmarks for the triangulation of robot position. An algorithm which was based on position computation on the set of available landmarks was utilized for the automatic selection of optimal landmarks. Findings showed that that several issues influence the performance of a landmark triplet. Results also indicated that the algorithm supported more than one order of magnitude reduction in uncertainty.

An integrated navigation system for an autonomous mobile robot is provided data on its environment by a Laser Range Finder and focuses on the macroscopic motion guiding the robot. This enables the robot to move toward the set location of which the navigation system has no prior knowledge. Two-dimensional floor maps are based on laser range images. Results show that mobile robots can be provided with basic explorative and navigational abilitiesby integrating the environment modeler and path planner.

In humans, maternal hypercholesterolemia during pregnancy promotes microscopical fatty streaks in the children. The mechanism is unknown. Fatty streaks are clinically silent, and many of them regress and never develop into advanced atherosclerosis. The aim of this study was to investigate whether hypercholesterolemia in pregnant mice induced more advanced atherosclerosis in their adult progeny. Hypercholesterolemic (HC) apolipoprotein E knockout (apoE−/−) female mice were mated with normocholesterolemic (NC) wild-type (apoE+/+) males and vice versa. All parents were almost identical genetically except for apoE. Therefore, all progeny became genetically identical and heterozygous apoE+/−. They were born of either HC (i.e. apoE−/−) or NC (i.e. apoE+/+) mothers. The progeny were killed 6 months after birth and the amount of atherosclerosis in the aortic root was assessed. Females developed more atherosclerosis than males (P<0.001) but, regardless of sex, maternal hypercholesterolemia during pregnancy had no influence on the amount of atherosclerosis in adult progeny. Males of HC mothers had lower plasma cholesterol levels than males of NC mothers. Thus, in mice, maternal hypercholesterolemia during pregnancy does not promote the development of advanced atherosclerosis in their adult progeny. [Copyright &y& Elsevier]

• The speltoid mutant WCAD1267 has a Ala155→Thr amino acid substitution in Q. • The mutation show that the first APETALA2 like domain is indispensable for Q function. • The mutant was discovered by a forward genetic application of an in silico TILLING resource. The major wheat domestication allele Q (encoding an APETALA2 like transcription factor) is responsible for the free threshing and square-headed spikes of modern wheat. Wild type q and null q' alleles cause a reversal to the speltoid phenotype. Q pleiotropically affects additional yield and quality traits so genetic variation in Q and its interaction partners remain important for crop improvement. Here we report the discovery of a novel q' allele that contribute to the molecular characterization of Q. This induced mutation cause an Ala→Thr substitution at a highly conserved position in the first of two APETALA2 like domains of the Q protein. The mutation correlates with a speltoid phenotype as expected for a loss of Q function. Thus, it is demonstrated that the first APETALA2 like domain is essential for Q function. The phenotype was discovered in a mutant from an in silico TILLING population and the causative mutation could be identified in the existing sequence data. This report therefore provides an example of a forward genetic application of in silico TILLING. [ABSTRACT FROM AUTHOR]

Highlights • Barley varieties showed different inhibition of xylanase and protease activity. • Apparent digestibility in pigs of nutrients varied with barley variety. • Exogenous xylanase had no major effect on digestibility of the measured nutrients. • Protease increased total tract digestibility of crude protein. Abstract Xylanase and protease inhibitors in cereals may be a reason for the varying efficacy of exogenous xylanase and protease in pig diets. The present study was conducted to evaluate the effect of xylanase and protease on the digestibility in pigs fed three barley varieties selected to be high and low in inhibitors. The cv. Invictus (spring barley) was selected to be low in xylanase inhibitors and cv. Hejmdal (winter barley) to be low in protease inhibitors, while SJ115158 (winter barley) was high in both xylanase and protease inhibitors. Growing pigs (34 ± 3 kg) were surgically fitted with a T-cannula in the terminal ileum and allotted to a 7 × 6 Youden square design, where 7 animals were fed with 7 diets for 6 weeks. Ileal samples were collected for 8 h on day 5 and 7 of each experimental week and fecal samples were collected from the first feces excreted on the same collection days. Titanium dioxide was added to all diets as an indigestible solid phase marker for the calculation of apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD). There was no consistent effect of variety or enzymes on the viscosity of ileal digesta. The ATTD of dry matter and organic matter was higher (P < 0.05) for Invictus than SJ115158, which was higher (P < 0.05) than Hejmdal. For Hejmdal, the AID of dry matter and organic matter was also lower (P < 0.05) compared to SJ115158. Supplementation of exogenous xylanase increased AID of dry matter, whereas the other evaluated components were unaffected. The ATTD of crude protein was lower (P = 0.027) for Hejmdal than for SJ115158 and exogenous protease increased (P = 0.004) ATTD of crude protein in both SJ115158 and Hejmdal. In conclusion, this study shows differences in nutrient digestibility among barley varieties and low efficacies of the selected exogenous enzymes independent of barley variety. [ABSTRACT FROM AUTHOR]

The present study demonstrates the optimization of a heat pump for an application with a large temperature glide on the sink side and a smaller temperature glide on the source side. The study includes a numerical simulation of a heat pump cycle for binary mixtures based on a list of 14 natural refrigerants. This approach enables a match of the temperature glide of sink and source with the temperature of the working fluid during phase change and thus, a reduction of the exergy destruction due to heat transfer. The model was evaluated for four different boundary conditions. The exergy destruction due to heat transfer, which is solely caused by the fluid having a non-ideal temperature profile was quantified and an indicator describing the glide match was defined to analyze its influence on the performance. The results indicated, that a good glide match can contribute to an increased performance. The increase in performance was dependent on the boundary conditions and reached up to 20% for a simple cycle and up to 27% if the superheating can be avoided. The temperature glide match in the source was identified to have a higher influence on the performance than in the sink. [ABSTRACT FROM AUTHOR]

The barley aleurone layer is an established model system for studying phytohormone signalling, enzyme secretion and programmed cell death during seed germination. Most analyses performed on the aleurone layer are end-point assays based on cell extracts, meaning each sample is only analysed at a single time point. By immobilising barley aleurone layer tissue on polydimethylsiloxane pillars in the lid of a multiwell plate, continuous monitoring of living tissue is enabled using multiple non-destructive assays in parallel. Cell viability and menadione reducing capacity were monitored in the same aleurone layer samples over time, in the presence or absence of plant hormones and other effectors. The system is also amenable to transient gene expression by particle bombardment, with simultaneous monitoring of cell death. In conclusion, the easy to handle and efficient experimental setup developed here enables continuous monitoring of tissue samples, parallelisation of assays and single cell analysis, with potential for time course studies using any plant tissue that can be immobilised, for example leaves or epidermal peels. [ABSTRACT FROM AUTHOR]