Graspar: a flexible, easily controllable robotic hand

With only one motor per finger and a simple, easy to maintain, mechanical structure, the Graspar robotic hand uses minimal computation to provide secure grasping of objects ranging from eggs and light bulbs to tennis rackets, coffee pots and stuffed toys. We first discuss currently developed hands, and show the motivation for our work. Next, we present the mechanical structure of our robotic hand and the antagonistic tendoning system. We then show how this structure moves and complies to the object surface. We discuss how we chose the pulley diameters for our tendoning system by maximizing the workspace of the fingers while mechanically insuring that the hand cannot collide with itself. Our control algorithm which uses simple mechanical switches is presented     

Characterisation of the Dynamic Interactions between Complex N-Glycans and Human CD22

CD22 (Siglec-2) is a B-cell surface inhibitory protein capable of selectively recognising sialylated glycans, thus dampening autoimmune responses against self-antigens. Here we have characterised the dynamic recognition of complex-type N-glycans by human CD22 by means of orthogonal approaches including NMR spectroscopy, computational methods and biophysical assays. We provide new molecular insights into the binding mode of sialoglycans in complex with h-CD22, highlighting the role of the sialic acid galactose moieties in the recognition process, elucidating the conformational behaviour of complex-type N-glycans bound to Siglec-2 and dissecting the formation of CD22 homo-oligomers on the B-cell surface. Our results could enable the development of additional therapeutics capable of modulating the activity of h-CD22 in autoimmune diseases and malignancies derived from B-cells.     

Lymphocyte blastogenesis inhibition by milk whey as an indicator of mastitis

Sixty milk whey samples prepared from quarters of five cows with a history of mastitis were tested for their ability to inhibit DNA synthesis in mitogen-stimulated lymphocytes. The inhibitory activity was compared with milk SCC, electrical conductivity, pH, and the number of colony-forming bacteria in the milk. Milk whey contained factors that inhibited DNA synthesis in cultured lymphocytes. Inhibition of mitogen-induced DNA synthesis increased with the clinical severity of mastitis and with increased values of indirect indicators of mastitis. The increases in inhibition and electrical conductivity were delayed past the increases in SCC. Milk whey (10 microliters) from quarters with clinical mastitis and from quarters with SCC greater than 900,000 inhibited 96 to 100%, 84 to 100%, and 69 to 100% of DNA synthesis in 3-d cultures of lymphocytes stimulated with Concanavalin A, phytohemagglutinin P, and pokeweed mitogen, respectively. The numbers of colony-forming bacteria correlated least with the inhibitory activity.     

Characterisation of n-channel germanium MOSFET with gate insulator formed by high-pressure thermal oxidation

N-channel Ge MOSFETs are fabricated with the use of a double-layer gate oxide consisting of electron beam evaporated SiO2 over a native GeO2 oxide, formed by highpressure thermal oxidation. Interface properties of the MOS structure, determined by capacitance/voltage and mobility measurements, are shown to be suitable for FET devices.     

Effect of aluminum doping on the high-temperature stability and piezoresistive response of indium tin oxide strain sensors

Ceramic strain sensors based on reactively sputtered indium tin oxide (ITO) thin films doped with aluminum are being considered to improve the high-temperature stability and response. Ceramic strain sensors were developed to monitor the structural integrity of components employed in aerospace propulsion systems operating at temperatures in excess of 1500 °C. Earlier studies using electron spectroscopy for chemical analysis (ESCA) studies indicated that interfacial reactions between ITO and aluminum oxide increase the stability of ITO at elevated temperature. The resulting ESCA depth files showed the presence of two new indium-indium peaks at 448.85 and 456.40 eV, corresponding to the indium 3d5 and 3d3 binding energies. These binding energies are significantly higher than those associated with stoichiometric indium oxide. Based on these studies, a combinatorial chemistry approach was used to screen large numbers of possible concentrations to optimize the stability and performance of Al-doped ceramic strain sensors. Scanning electron microscopy was used to analyze the combinatorial libraries in which varying amounts of aluminum were incorporated into ITO films formed by cosputtering from multiple targets. Electrical stability and piezoresistive response of these films were compared to undoped ITO films over the same temperature range.     

Headwater Streams of Florida: Types,Distribution and a Framework for Conservation

Using geographic information system and topographic maps, 5829 headwater streams in Florida were surveyed for several parameters including elevation, stream length, flow regime and surrounding geology, and vegetation. Each was assigned to one of four headwater types: wetland, seep, lake, and spring. Wetland headwaters were the most common and widespread followed by seeps, many displaying temporary flow, while springs were perennial and least numerous. Four groups of Florida rivers were identified through cluster analysis of drainage densities (number headwaters/km of river length). Group 1 consisted of six rivers with lowest drainage densities (0.30–1.39 streams/km main channel). All were coastal rivers of peninsular Florida and, with one exception, drain to the Gulf of Mexico. Seven of eight rivers (group 2) with intermediate drainage densities (1.77–3.04 streams/km main channel) were located in peninsular Florida. Only three of 12 rivers comprising the two groups (groups 3 and 4) with greatest drainage densities (5.16–9.37 and 15.49–16.96 streams/km main channel) were not located in the Florida panhandle. Stream conservation efforts should focus on both highly complex dendritic river networks of the panhandle and on the 7000 km² area in central Florida mostly lacking headwaters that may become a significant dispersal bottleneck for aquatic biota seeking refugia farther north from projected climate change. Copyright © 2014 John Wiley & Sons, Ltd.     

Free space measurements of negative refraction with varying angles of incidence

We report free space, microwave measurements with varying incidence angle on a material that exhibits a negative index of refraction. The experiments measure the index of refraction directly, for normal incidence, on prisms with three different apex angles. Snell's Law and the measured index are then used to verify refraction for off-normal incidence. The metamaterials used to construct the prisms are comprised of parallel metallic layers of posts and either "Greek key" spiral or split ring resonators. Despite this highly anisotropic composition, the measured refractive index was found to be nearly constant for exit angles up to 52/spl deg/ off the normal to the prism hypotenuse. In addition to being the first free space experimental verification of Snell's Law off the optical axis for this type of metamaterial, the measurements prove that the common parallel plate structures of negative index metamaterials are not acting as guided wave media.     

The Warp machine on Navlab

The authors review the history of the Carnegie-Mellon Warp machine on Navlab, an autonomous land vehicle, and describe three Navlab vision systems implemented on the Warp machine. They then critically evaluate components of Warp in light of this experience. The Warp machine was used to implement stereo vision for obstacle avoidance and color-based road-following systems. The stereo-vision system was FIDO, which is derived from some of the earliest work in vision-guided robot vehicle navigation. Two color-based road following systems were implemented; one adapted conventional vision techniques to the problem of road recognition and the other used a neural network-based technique to learn road following online. Finally, the authors discuss the value of applications integration with machine development, discuss the limitations of the attached processor model, and give recommendations for future systems     

Application of pattern recognition in arson investigation

The authors discuss the application of pattern recognition methods to the development of techniques for aiding the arson investigator in determining trends in incendiary and suspicious fires.