A Study of the Rao-Blackwellised Particle Filter for Efficient and Accurate Vision-Based SLAM

With recent advances in real-time implementations of filters for solving the simultaneous localization and mapping (SLAM) problem in the range-sensing domain, attention has shifted to implementing SLAM solutions using vision-based sensing. This paper presents and analyses different models of the Rao-Blackwellised particle filter (RBPF) for vision-based SLAM within a comprehensive application architecture. The main contributions of our work are the introduction of a new robot motion model utilizing structure from motion (SFM) methods and a novel mixture proposal distribution that combines local and global pose estimation. In addition, we compare these under a wide variety of operating modalities, including monocular sensing and the standard odometry-based methods. We also present a detailed study of the RBPF for SLAM, addressing issues in achieving real-time, robust and numerically reliable filter behavior. Finally, we present experimental results illustrating the improved accuracy of our proposed models and the efficiency and scalability of our implementation.     

Development of an Elastoviscoplastic Microstructural-Based Continuum Model to Predict Permanent Deformation in Hot Mix Asphalt

Permanent deformation in hot mix asphalt is caused by a combination of densification (decrease in volume and hence increase in density) and shear deformation. The primary objective of this paper is to develop an elastoviscoplastic model that accounts for the influence of important microstructure properties such as anisotropy and damage on permanent deformation. The model incorporates a yield surface based on the Drucker-Prager function that is modified to capture the influence of stress state on the material response. Also, parameters that reflect the directional distribution of aggregates and damage density in the microstructure are included in this yield surface model. The elastoviscoplastic model is converted into a numerical formulation and is implemented in finite element (FE). The FE model is used in this study to simulate experimental measurements under different confining pressures and strain rates.     

Radiation down-regulates replication origin activity throughout the S phase in mammalian cells

An asynchronous culture of mammalian cells responds acutely to ionizing radiation by inhibiting the overall rate of DNA replication by approximately 50% for a period of several hours, presumably to allow time to repair DNA damage. At low and moderate doses, this S phase damage-sensing (SDS) pathway appears to function primarily at the level of individual origins of replication, with only a modest inhibition of chain elongation per se. We have shown previously that the majority of the inhibition observed in an asynchronous culture can be accounted for by late G1cells that were within 2-3 h of entering the S period at the time of irradiation and which then fail to do so. A much smaller effect was observed on the overall rate of replication in cells that had already entered the S phase. This raised the question whether origins of replication that are activated within S phase per se are inhibited in response to ionizing radiation. Here we have used a two-dimensional gel replicon mapping strategy to show that cells with an intact SDS pathway completely down-regulate initiation in both early- and late-firing rDNA origins in human cells. We also show that initiation in mid- or late-firing rDNA origins is not inhibited in cells from patients with ataxia telangiectasia, confirming the suggestion that these individuals lack the SDS pathway.     

Memory complaints and abilities among depressed older adults.

The relation between complaints of memory problems and memory test performance was examined among depressed (n?=?25) and nondepressed (n?=?25) adults over the age of 40 years. Depressed adults were diagnosed from interviews using Diagnostic and Statistical Manual of Mental Disorders (DSM-III) criteria and from responses to the Beck Depression Inventory. A dissociation between memory complaints and performance was observed. Depressed adults complained of greater problems in memory than nondepressed adults. However, the memory test performances of both groups were in the average-to-above-average range. These results are discussed in light of the role of self-deprecating cognitive distortions in the tendency of depressed individuals to negatively evaluate all their abilities, including their memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Factors Influencing the Adhesion of Microorganisms to Surfaces

Starvation, growth phase, and carbon source influenced bacterial cell surface hydrophobicity. Both the number and kind of microorganisms that colonized metal surfaces depended on the type of metal and the presence of an imposed electrical potential. No significant differences in attachment and growth of a pure culture were observed when metal surfaces were dipped in an exogenous energy source. The chemical composition of naturally occurring adsorbed organic films on metal surfaces was shown to be independent of surface composition and polarization.     

Atropine poisoning after drinking Indian tonic water

After 13.5 years in vivo a 2-0 Terylene frontalis loop was excised because of an insufficiency. Histology showed a persisting giant cell reaction while lymphocytes were almost totally absent. The fibrils of the suture seemed to be intact. However, they were separated by ingrowing connective tissue which, on theoretical grounds, should improve the function of the frontal muscle on the upper eyelid. Therefore, insufficiency of the loop was probably caused by the (subclinical) foreign body reaction or the long-lasting mechanical stress leading to tissue damage.     

Reduced performance of male and female athletes at 580 m altitude

Patients with craniocervical mandibular (TMD) disorders can present with tinnitus as a primary or secondary complaint. The embryology and functional anatomy of the middle ear, temporomandibular joint, muscles of mastication and associated tendons, ligaments, blood vessels, nerves and lymphatics was found to be helpful in establishing etiologic concepts which relate tinnitus to these temporomandibular disorders. In addition to etiologic concepts, treatment modalities are described. The authors relate their experiences as well as those of others with different patient populations.     

Predicting educational attainment, occupational achievement, intellectual skill, and personal adjustment among gifted men and women.

The cognitive potential of many gifted children goes unfulfilled. This study was designed to isolate factors, other than cognitive skill, that might predict adult achievements and personal adjustment among the gifted. Subjects were 1,069 gifted men (n?=?595) and women (n?=?474) who have been followed for 60 years as part of the Terman Genetic Studies of Genius. Childhood personality traits, parental education, and early home environment variables were examined as predictors of educational and occupational achievement among adults. The final model depicted five longitudinal relationships that predicted educational attainment, intellectual skill, and personal adjustment among both men and women. Two additional paths explained occupational achievement. The implications of this final model are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Human Adipose Tissue Conditioned Media from Lean Subjects Is Protective against H2O2 Induced Neurotoxicity in Human SH-SY5Y Neuronal Cells

Adipose tissue secretes numerous hormone-like factors, which are known as adipokines. Adipokine receptors have been identified in the central nervous system but the potential role of adipokine signaling in neuroprotection is unclear. The aim of this study is to determine (1) Whether adipokines secreted from cultured adipose tissue of lean humans is protective against oxidative stress-induced neurotoxicity in human SH-SY5Y neuronal cells; and (2) To explore potential signaling pathways involved in these processes. Adipose tissue conditioned media (ATCM) from healthy lean subjects completely prevented H₂O₂ induced neurotoxicity, while this effect is lost after heating ATCM. ATCM activated the phosphorylation of ERK1/2, JNK and Akt at serine 308 in SH-SY5Y cells. PD98059 (25 µM), SP600125 (5 µM) and LY29400 (20 µM) partially blocked the protective effects of ATCM against H₂O₂ induced neurotoxicity. Findings demonstrate that heat-sensitive factors secreted from human adipose tissue of lean subjects are protective against H₂O₂ induced neurotoxicity and ERK1/2, JNK, and PI3K signaling pathways are involved in these processes. In conclusion, this study demonstrates preliminary but encouraging data to further support that adipose tissue secreted factors from lean human subjects might possess neuroprotective properties and unravel the specific roles of ERK1/2, JNK and PI3K in these processes.