Collision-free motion of two robot arms in a common workspace

Collision-free motion of two robot arms in a common workspace is investigated. A collision-free motion is obtained by detecting collisions along the preplanned trajectories using a sphere model for the wrist of each robot and then modifying the paths and/or trajectories of one or both robots to avoid the collision. Detecting and avoiding collisions are based on the premise that: preplanned trajectories of the robots follow a straight line; collisions are restricted to between the wrists of the two robots (which corresponds to the upper three links of PUMA manipulators); and collisions never occur between the beginning points or end points on the straight line paths. The collision detection algorithm is described and some approaches to collision avoidance are discussed

Bar-grid oscillators

Grid oscillators are an attractive way of obtaining high power levels from the solid-state devices, since potentially the output powers of thousands of individual devices can be combined. The active devices do not require an external locking signal, and the power combining is done in free space. Thirty-six transistors were mounted on parallel brass bars, which provide a stable bias and have a low thermal resistance. The output power degraded gradually when the devices failed. The grid gave an effective radiated power of 3 W at 3 GHz. The directivity was 11.3 dB, and the DC-to-RF efficiency was 22%. Modulation capabilities of the grid were demonstrated. An equivalent circuit model for the grid is derived, and comparison with experimental results is shown

Identification of Novel Retroid Agents in Danio rerio, Oryzias latipes, Gasterosteus aculeatus and Tetraodon nigroviridis

Retroid agents are genomes that encode a reverse transcriptase (RT) and replicate or transpose by way of an RNA intermediate. The Genome Parsing Suite (GPS) is software created to identify and characterize Retroid agents in any genome database (McClure et al. 2005). The detailed analysis of all Retroid agents found by the GPS in Danio rerio (zebrafish), Oryzias latipes (medaka), Gasterosteus aculeatus (stickleback) and Tetraodon nigroviridis (spotted green pufferfish) reveals extensive Retroid agent diversity in the compact genomes of all four fish. Novel Retroid agents were identified by the GPS software: the telomerase reverse transcriptase (TERT) in O. latipes, G. aculeatus and T. nigroviridis and a potential TERT in D. rerio, a retrotransposon in D. rerio, and multiple lineages of endogenous retroviruses (ERVs) in D. rerio, O. latipes and G. aculeatus

Neighborhoods, Daily Activities, and Measuring Health Risks Experienced in Urban Environments.

Studies of place and health often classify a subject\u27s exposure status according to that which is present in their neighborhood of residence. One\u27s neighborhood is often proxied by designating it to be an administratively defined unit such as census tract, to make analysis feasible. Although it is understood that residential space and actual lived space may not correspond and therefore exposure misclassification may result, few studies have the opportunity to investigate the implications of this issue concretely. A population-based case-control study that is currently underway provides one such opportunity. Adolescent victims of assault in Philadelphia, Pennsylvania, USA, and a control sample of adolescents drawn randomly from the community are being enrolled to study how alcohol consumption and time spent nearby alcohol outlets - individual-level and environmental-level risk factors for violence, respectively - over the course of daily activities relate to the likelihood of being assaulted. Data from a rapport-building exercise consist of hand-drawn sketches that subjects drew on street maps when asked to indicate the area considered their neighborhood. The main data consist of self-reported, detailed paths of the routes adolescents traveled from one location to the next over the course of one full day. Having noticed interesting patterns as the data collection phase proceeds, we present here an analysis conducted with the data of 55 control subjects between 15 and 19 years old. We found that hand-drawn neighborhoods and activity paths did not correspond to census tract boundaries, and time subjects spent in close proximity to alcohol outlets during their daily activities was not correlated with the prevalence of alcohol outlets in the census tract of their residence. This served as a useful example demonstrating how classifying subjects as exposed based solely on the prevalence of the exposure in the geographic area of their residence may misrepresent the exposure that is etiologically meaningful

Geophysical investigations of a geothermal anomaly at Wadi Ghadir, eastern Egypt

During regional heat flow studies a geothermal anomaly was discovered approximately 2 km from the Red Sea coast at Wadi Ghadir, in the Red Sea Hills of Eastern Egypt. A temperature gradient of 55 C/km was measured in a 150 m drillhole at this location, indicating a heat flow of approximately 175 mw/sqm, approximately four times the regional background heat flow for Egypt. Gravity and magnetic data were collected along Wadi Ghadir, and combined with offshore gravity data, to investigate the source of the thermal anomaly. Magnetic anomalies in the profile do not coincide with the thermal anomaly, but were observed to correlate with outcrops of basic rocks. Other regional heat flow and gravity data indicate that the transition from continental to oceanic type lithosphere occurs close to the Red Sea margin, and that the regional thermal anomaly is possibly related to the formation of the Red Sea

BIOCHEMICAL AND FUNCTIONAL CHARACTERIZATION OF A POTENTIAL 2’, 3’-CYCLIC-NUCLEOTIDE 3’-PHOSPHODIESTERASE (CNPASE) FOUND IN TUMORIGENIC FISH RETROVIRUSES

Tumorigenic retroviruses cause seasonal cancer in fish. Many of these retroviruses contain an interesting unknown gene of cellular origin. Computational programs predict that this gene encodes a CNPase (2’,3’-Cyclic-nucleotide 3’-phosphodiesterase). In mammals, the natural function of CNPase is unknown. The purpose of the experiment is to isolate and characterize the potential viral CNPase. Utilizing a vector from zebrafish endogenous retrovirus (ZFERV), the potential CNPase genetic sequence will be isolated and analyzed. Thereafter, the potential CNPase protein will be expressed and purified, and characterization will include enzymatic activity assays, inhibition activity studies, and NMR studies. Future studies involve functional characterization of the potential CNPase, including binding and transformation studies. Potential CNPase is predicted to function as an oncogene that promotes tumorigenesis in fish. Exploring this potential CNPase may aide in the treatment of affected fish as well as provide insight into the function of this enzyme in humans

Laboratory implementation of edge illumination X-ray phase-contrast imaging with energy-resolved detectors

Edge illumination (EI) X-ray phase-contrast imaging (XPCI) has potential for applications in different fields of research, including materials science, non-destructive industrial testing, small-animal imaging, and medical imaging. One of its main advantages is the compatibility with laboratory equipment, in particular with conventional non-microfocal sources, which makes its exploitation in normal research laboratories possible. In this work, we demonstrate that the signal in laboratory implementations of EI can be correctly described with the use of the simplified geometrical optics. Besides enabling the derivation of simple expressions for the sensitivity and spatial resolution of a given EI setup, this model also highlights the EI’s achromaticity. With the aim of improving image quality, as well as to take advantage of the fact that all energies in the spectrum contribute to the image contrast, we carried out EI acquisitions using a photon-counting energy-resolved detector. The obtained results demonstrate that this approach has great potential for future laboratory implementations of EI. © (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only

Identifying The Health Needs In Rural Appalachian Ohio: Outcomes Of A Rural Community-Academic Partnership

To identify health issues in two rural counties, a needs assessment was developed by health officials and researchers. Focus groups (n = 32) and interviews (n = 8) were conducted among community leaders and a modified BRFFS survey was completed by 399 community members. Results indicated the health of the participants was influenced by: 1) rural Appalachian culture, 2) geography and access to health care, and 3) lack of access/knowledge about preventive health behaviors. These issues likely contributed to 30% obesity prevalence among the sample, which was prioritized as the main health issue for both counties.