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This paper presents an enhanced algorithm for matching laser scan maps using histogram correlations. The histogram representation effectively summarizes a map's salient features such that pairs of maps can be matched efficiently without any prior guess as to their alignment. The histogram matching algorithm has been enhanced in order to work well in outdoor unstructured environments by using entropy metrics, weighted histograms and proper thresholding of quality metrics. Thus our large-scale scan-matching SLAM implementation has a vastly improved ability to close large loops in real-time even when odometry is not available. Our experimental results have demonstrated a successful mapping of the largest area ever mapped to date using only a single laser scanner. We also demonstrate our ability to solve the lost robot problem by localizing a robot to a previously built map without any prior initialization.

We examined the effects of two African herbal medicines recommended for HIV/AIDS patients on antiretroviral metabolism. Extracts from Hypoxis and Sutherlandia showed significant effects on cytochrome P450 3A4 metabolism and activated the pregnane X receptor approximately twofold. P-glycoprotein expression was inhibited, with Hypoxis showing 42-51% and Sutherlandia showing 19-31% of activity compared with verapamil. Initiating policies to provide herbal medicines with antiretroviral agents may put patients at risk of treatment failure, viral resistance or drug toxicity.

We examined the effects of two African herbal medicines recommended for HIV/AIDS patients on antiretroviral metabolism. Extracts from Hypoxis and Sutherlandia showed significant effects on cytochrome P450 3A4 metabolism and activated the pregnane X receptor approximately twofold. P-glycoprotein expression was inhibited, with Hypoxis showing 42-51% and Sutherlandia showing 19-31% of activity compared with verapamil. Initiating policies to provide herbal medicines with antiretroviral agents may put patients at risk of treatment failure, viral resistance or drug toxicity.

The paper presents a biologically-inspired perception-action scheme for robots interacting with real-world environments, grounded in the broad hypothesis that, like in humans, perception and action are improved in speed and accuracy by expectation mechanisms: perception crucially involves comparison processes between incoming stimuli and expected perceptions (EPs). In the proposed approach, EPs are built on the basis of previous perceptions, current motor commands, proprioception, and internal models of the robot and the environment. In contrast to pure reactive approaches, background knowledge plays here a helpful role, as it reduces the computational burden of perception and motor coordination tasks, in partially structured environments. In the work presented here, an EP mechanism has been applied in the visuo-motor coordination of an anthropomorphic 8 d.o.f. robotic manipulator equipped with a vision system, in order to validate the viability and effectiveness of the initial hypothesis.

The paper presents a biologically-inspired perception-action scheme for robots interacting with real-world environments, grounded in the broad hypothesis that, like in humans, perception and action are improved in speed and accuracy by expectation mechanisms: perception crucially involves comparison processes between incoming stimuli and expected perceptions (EPs). In the proposed approach, EPs are built on the basis of previous perceptions, current motor commands, proprioception, and internal models of the robot and the environment. In contrast to pure reactive approaches, background knowledge plays here a helpful role, as it reduces the computational burden of perception and motor coordination tasks, in partially structured environments. In the work presented here, an EP mechanism has been applied in the visuo-motor coordination of an anthropomorphic 8 d.o.f. robotic manipulator equipped with a vision system, in order to validate the viability and effectiveness of the initial hypothesis.

Hydrotalcite-like compounds were prepared using MgSO4 solution obtained from the H2SO4 dissolution of serpentinite in order to investigate a useful application of the ore. The ion exchange of sulphate ions for carbonate ions was studied., Hydrotalcite-like compounds were prepared using MgSO4 solution obtained from the H2SO4 dissolution of serpentinite in order to investigate a useful application of the ore. The ion exchange of sulphate ions for carbonate ions was studied.

High-purity silica (SiO2 content above 99.5%) was obtained by acid leaching of serpentinite from the Hidaka district with 6 M HCl at 100 degrees C for 12 hours. The microtexture of the silica retained the morphology of the original chrysotile serpentine, each fibrous aggregate consisting of fibres about 0.07 micrometers in diameter. Specific surface area varied from 5 m2/g for the original material up to 400 m2/g for acid leached material containing 10% MgO. The surface area of amorphous silica was maintained at 150 m2/g in the temperature range up to 800 degrees C but decreased to 40 m2/g at 1 000 degrees C. The high silica content, large specific area and high reactivity were very suitable for industrial applications. This was shown by the synthesis of ZSM-5 zeolite, calcium silicate hydrate, silicon carbide and fluor-mica., High-purity silica (SiO2 content above 99.5%) was obtained by acid leaching of serpentinite from the Hidaka district with 6 M HCl at 100 degrees C for 12 hours. The microtexture of the silica retained the morphology of the original chrysotile serpentine, each fibrous aggregate consisting of fibres about 0.07 micrometers in diameter. Specific surface area varied from 5 m2/g for the original material up to 400 m2/g for acid leached material containing 10% MgO. The surface area of amorphous silica was maintained at 150 m2/g in the temperature range up to 800 degrees C but decreased to 40 m2/g at 1 000 degrees C. The high silica content, large specific area and high reactivity were very suitable for industrial applications. This was shown by the synthesis of ZSM-5 zeolite, calcium silicate hydrate, silicon carbide and fluor-mica.

Experimental studies of the solubilities of nickel and iron in hydroxides, oxides, laterites and garnieritic ores in the sodium dithionite-citrate solution were carried out to obtain fundamental data on the mineralogical state of nickel and iron in nickeliferous laterite deposits. The solubilities of nickel and iron in the artificial reagents increased with leaching time and temperature and the weight of reducing reagent, reaching 95.5-98.0% when leaching for 10 minutes at 70 degree C with 1g of reagent. When examining laterite ore profiles from Pulot, Philippines, the solubility of nickel and iron tended to increase with depth until the upper part of the garnierite layer was reached., Experimental studies of the solubilities of nickel and iron in hydroxides, oxides, laterites and garnieritic ores in the sodium dithionite-citrate solution were carried out to obtain fundamental data on the mineralogical state of nickel and iron in nickeliferous laterite deposits. The solubilities of nickel and iron in the artificial reagents increased with leaching time and temperature and the weight of reducing reagent, reaching 95.5-98.0% when leaching for 10 minutes at 70 degree C with 1g of reagent. When examining laterite ore profiles from Pulot, Philippines, the solubility of nickel and iron tended to increase with depth until the upper part of the garnierite layer was reached.