Calibrating a 4-wheel mobile robot

When a mobile robot is constructed the odometry must be calibrated. Calibrating a 4-wheel robot requires the accurate measurement of steering angle as well as translation and rotation. Some measurements are made with a tape measure and some with ultrasonic sensors. The measurements are used to determine the parameters of the odometry calibration matrix and the steering kinematic model. A procedure for calibrating a 4-wheel robot is discussed

<i>Schistosoma mansoni</i> cercariae experience influx of macromolecules during skin penetration

We have observed that when cercariae penetrate the skin of mice, there is influx into their tissues of Lucifer Yellow and certain labelled molecules of up to 20 kDa molecular weight. This observation was made using a variety of fluorescent membrane-impermeant compounds injected into the skin before the application of cercariae. This unexpected phenomenon was investigated further by transforming cercariae in vitro in the presence of the membrane-impermeant compounds and examining the distribution by microscopy. In schistosomula derived from this procedure, the nephridiopore and surface membrane were labelled while the pre- and post-acetabular glands were not labelled. The region associated with the oesophagus within the pharyngeal muscle clearly contained the fluorescent molecules, as did the region adjacent to the excretory tubules and the germinal mass. We used cercariae stained with carmine to aid identification of regions labelled with Lucifer Yellow. Although the mechanism of this influx is unclear, the observation is significant. From it, we can suggest an hypothesis that, during skin penetration, exposure of internal tissues of the parasite to external macromolecules represents a novel host-parasite interfac

‘Flex Your Power’: Energy crises and the shifting rhetoric of the grid

In response to widespread power outages, rolling blackouts, and ubiquitous energy debates, this essay considers our relation to energy and the grid that produces it. First, we investigate California\u27s multimedia Flex Your Power campaign, which defines consumers as nodes of the grid to emphasize their responsibility to maintain a stable energy supply. Second, we examine state and national responses to the 2003 blackout in the Northeastern United States, attending to three strategies through which grid administrators sought to impose order, enact hierarchy, and deindividuate power. We propose that the grid invokes personalization at the local level and abstraction at the national level. These contradictory (but overlapping) narratives show a complex, nuanced set of relations between human society and mechanized processes of power distribution

TLTF in cerebrospinal fluid for detection and staging of T. b. gambiense infection

Background: Trypanosome-derived lymphocyte triggering factor (TLTF) is a molecule released by African trypanosomes that interacts with the host immune system, resulting in increased levels of IFN-c production. Methodology/Principal findings: TLTF and anti-TLTF antibodies were assessed in sera and cerebrospinal fluid (CSF) from patients infected with Trypanosoma brucei gambiense (T. b. gambiense) in an attempt to identify alternative markers for diagnosis and stage determination of human African trypanosomiasis or sleeping sickness. Seventy-four serum and sixtyone CSF samples from patients with parasitologically confirmed infection and known disease stage along with 13 sera and CSF from uninfected controls were tested. In serum the levels of anti-TLTF antibodies were unrelated to the disease stage. In contrast, levels of anti-TLTF antibodies in CSF were higher in intermediate/late stages than in early stage disease patients. Specificity of the detected antibodies was assessed by inhibition of TLTF bioactivity as represented by its ability to induce IFN-c production. Additionally, TLTF was detected in CSF from late stage patients by Western blotting with the anti-TLTF specific monoclonal antibody MO3. Conclusions/Significance: These findings suggest a new possibility for disease diagnosis with focus on involvement of the CNS through detection of TLTF and anti-TLTF antibodies in the CSF