SeaVipers - Computer Vision and Inertial Position Reference Sensor System (CVIPRSS)

This work describes the design and development of an optical, Computer Vision (CV) based sensor for use as a Position Reference System (PRS) in Dynamic Positioning (DP). Using a combination of robotics and CV techniques, the sensor provides range and heading information to a selected reference object. The proposed optical system is superior to existing ones because it does not depend upon special reflectors nor does it require a lengthy set-up time. This system, the Computer Vision and Inertial Position Reference Sensor System (CVIPRSS, pronounced \nickname), combines a laser rangefinder, infrared camera, and a pan--tilt unit with the robust TLD (Tracking--Learning--Detection) object tracker. In this work, a \nickname ~prototype is evaluated, showing promising results as viable PRS with research, commercial, and industrial applications

Observation of a two-dimensional electron gas at CaTiO3_3 film surfaces

The two-dimensional electron gas at the surface of titanates gathered attention due to its potential to replace conventional silicon based semiconductors in the future. In this study, we investigated films of the parent perovskite CaTiO$_3$, grown by pulsed laser deposition, by means of angular-resolved photoelectron spectroscopy. The films show a c(4x2) surface reconstruction after the growth that is reduced to a p(2x2) reconstruction under UV-light. At the CaTiO$_3$ film surface, a two-dimensional electron gas (2DEG) is found with an occupied band width of 400 meV. With our findings CaTiO$_3$ is added to the group of oxides with a 2DEG at their surface. Our study widens the phase space to investigate strontium and barium doped CaTiO$_3$ and the interplay of ferroelectric properties with the 2DEG at oxide surfaces. This could open up new paths to tailor two-dimensional transport properties of these systems towards possible applications

Monte Carlo model of electron energy degradation in a CO2 atmosphere

A Monte Carlo model has been developed to study the degradation of <1000 eV electrons in an atmosphere of CO2, which is one of the most abundant species in Mars' and Venus' atmospheres. The e-CO2 cross sections are presented in an assembled set along with their analytical representations. Monte Carlo simulations are carried out at several energies to calculate the "yield spectra", which embodied all the information related to electron degradation process and can be used to calculate "yield" (or population) for any inelastic process. The numerical yield spectra have been fitted analytically resulting in an analytical yield spectra (AYS). We have calculated the mean energy per ion pair and efficiencies for various inelastic processes, including the double and dissociative double ionization of \car\ and negative ion formation. The energy distribution of the secondary electrons produced per incident electron is also presented at few incident energies. The mean energy per ion pair for CO2 is 37.5 (35.8) eV at 200 (1000) eV, compared to experimental value 32.7 eV at high energies. Ionization is the dominant loss process at energies above 50 eV with contribution of ~50%. Among the excitation processes, 13.6 eV and 12.4 eV states are the dominant loss processes consuming ~28% energy above 200 eV. Around and below ionization threshold, 13.6 eV, 12.4 eV, and 11.1 eV, followed by 8.6 eV and 9.3 eV excitation states are important loss processes, while below 10 eV vibrational excitation dominates.Comment: 31 pages, 13 figure

Novel Human Rhinoviruses and Exacerbation of Asthma in Children1

To determine links between human rhinoviruses (HRV) and asthma, we used data from a case–control study, March 2003–February 2004, among children with asthma. Molecular characterization identified several likely new HRVs and showed that association with asthma exacerbations was largely driven by HRV-A and a phylogenetically distinct clade of 8 strains, genogroup C

Electronic and Structural Properties of a 4d-Perovskite: Cubic Phase of SrZrO3_3

First-principles density functional calculations are performed within the local density approximation to study the electronic properties of SrZrO$_3$, an insulating 4d-perovskite, in its high-temperature cubic phase, above 1400 K, as well as the generic 3d-perovskite SrTiO$_3$, which is also a d^0-insulator and cubic above 105 K, for comparison reasons. The energy bands, density of states and charge density distributions are obtained and a detailed comparison between their band structures is presented. The results are discussed also in terms of the existing data in the literature for both oxides.Comment: 5 pages, 2 figure

Comparative Study of Quality Characteristics of Korean Soy Sauce Made with Soybeans Germinated Under Dark and Light Conditions

This study was conducted to evaluate the effects of germinating soybeans under dark and light conditions on the quality characteristics of Korean soy sauce made with germinated soybeans. The germination rate of soybeans germinated under dark conditions (GSD) was higher than that of soybeans germinated under light conditions (GSL), whereas the lengths of sprouts and relative weights of GSL did not differ from those of GSD. The L, a, b, and ΔT values of GSL were significantly lower than GSD. The color of GSD remained yellow, while GSL changed to a green color due to photosynthesis by chlorophyll. The total amino acid contents in soy sauce fermented with soybeans germinated under dark conditions (SSGD) and soy sauce fermented with soybeans germinated under light conditions (SSGL) were lower than in soy sauce fermented with non-germinated soybeans (SNGS). The levels of isoflavone content in SSGD and SSGL were significantly increased compared to the SNGS. In conclusion, the germination of soybeans under dark and light conditions is not only an increasing organoleptic preference, but also has implications for the health benefits of Korean soy sauce

Experimental Helicobacter marmotae infection in A/J mice causes enterohepatic disease

Helicobacter marmotae has been identified in the inflamed livers of Eastern woodchucks (Marmota monax) infected with woodchuck hepatitis virus (WHV), as well as from the livers of WHV-negative woodchucks. Because the majority of WHV-positive woodchucks with hepatic tumours were culture or PCR positive for this helicobacter, and WHV-negative woodchucks with H. marmotae had hepatitis, the bacterium may have a role in tumour promotion related to chronic inflammation. In this study, the type strain of H. marmotae was inoculated intraperitoneally into 48 male and female A/J mice, a strain noted to be susceptible to Helicobacter hepaticus-induced liver tumours. Sixteen mice served as mock-dosed controls. At 6, 12 and 18 months post-inoculation (p.i.), there were statistically significant (P<0.05) differences in mean inflammation scores for the caecum and proximal colon between experimentally infected and control mice. Differences in hepatic inflammation were significant (P<0.05) at 6 and 12 months p.i. between the two groups but not at the 18 month time point. Two infected male mice had livers with severe hepatitis, and the liver samples were culture positive for H. marmotae. Serum IgG levels in the mice dosed with H. marmotae were elevated for the duration of the study. These results demonstrate that the woodchuck helicobacter can successfully colonize mice and cause enterohepatic disease. In the future, a mouse-adapted strain of H. marmotae could be selected to maximize colonization and lesion development. Such a woodchuck helicobacter-infected mouse model could be used to dissect potential mechanisms of microbial co-carcinogenesis involved in tumour development in woodchucks with WHV and in humans with hepatitis B virus

Pathogenic Intestinal Bacteria Enhance Prostate Cancer Development via Systemic Activation of Immune Cells in Mice

A role for microbes has been suspected in prostate cancer but difficult to confirm in human patients. We show here that a gastrointestinal (GI) tract bacterial infection is sufficient to enhance prostate intraepithelial neoplasia (PIN) and microinvasive carcinoma in a mouse model. We found that animals with a genetic predilection for dysregulation of wnt signaling, Apc[superscript Min/+] mutant mice, were significantly susceptible to prostate cancer in an inflammation-dependent manner following infection with Helicobacter hepaticus. Further, early neoplasia observed in infected Apc[superscript Min/+] mice was transmissible to uninfected mice by intraperitoneal injection of mesenteric lymph node (MLN) cells alone from H. hepaticus-infected mutant mice. Transmissibility of neoplasia was preventable by prior neutralization of inflammation using anti-TNF-α antibody in infected MLN donor mice. Taken together, these data confirm that systemic inflammation triggered by GI tract bacteria plays a pivotal role in tumorigenesis of the prostate gland.RO1CA108854National Institute of Environmental Health Sciences (Massachusetts Institute of Technology. Center for Environmental Health Sciences Pilot Project Award P30-ES002109

Nanostructuring perovskite oxides: The impact of SrTiO3 nanocubes 3D self-assembly on thermal conductivity.

Nanostructuring the perovskite oxide SrTiO3 via 3D assemblage of nanocubes is shown to lower the thermal conductivity over a broad range of temperatures. This is particularly valuable in thermoelectric material applications. The assemblages are composed of pristine perovskite grain interiors confined by SrO or TiO2-rich interfaces resembling Ruddlesden Popper and Magneli phases. The optimum performance in terms of the thermoelectric device applications are predicted to come from SrTiO3 nanocubes synthesised in a Sr-rich environment, although TiO2-rich nanocubes would have an increased strength. The vibrational fingerprint of the assemblages, characterized by a combination of lattice and molecular dynamics, display the characteristic modes of the perovskite structure and significant interface vibrational modes, some at very low frequency. TiO2-rich assemblages display splitting of the active modes similar to anatase providing a way to distinguish them from SrO-rich assemblages. Finally, we show that the IR active low vibrational frequencies are sensitive to the structure and stacking of the nanocubes indicating that it could be an efficient experimental route for identifying and characterizing the material with very low thermal conductivity