Laser-generated spark morphology and temperature records from emission and Rayleigh scattering studies

Using both Rayleigh scattering and time-resolved emission spectroscopy, we have recorded the spatial and temporal evolution of laser-generated sparks in argon from changes during the first ten of nano-seconds to complete dissipation, which occurs in a time span of approximately 5 ms. Maps of either emission intensity or argon density spanning the entire region affected by the energy deposited by the laser show the dissipation of the spark in detail. Immediately after ignition, the argon plasma occupies an ellipsoidal volume of roughly 3-mm vertical (axial) length. After approximately 20-40 micros, the spark region has transformed into a toroidal shape in a plane perpendicular to the vertical axis, with a radius of approximately 1.5 mm. The torus rises slowly up and expands noticeably in the radial direction. A record of peak temperatures of the spark ranging from approximately 10,000 K at 60-micros delay time to approximately 450 K at 4-ms delay time indicate cooling rates from approximately 100 to 1 K/micros at these times.     

Effects of atmospheric ozone on microarray data quality

A data anomaly was observed that affected the uniformity and reproducibility of fluorescent signal across DNA microarrays. Results from experimental sets designed to identify potential causes (from microarray production to array scanning) indicated that the anomaly was linked to a batch process; further work allowed us to localize the effect to the posthybridization array stringency washes. Ozone levels were monitored and highly correlated with the batch effect. Controlled exposures of microarrays to ozone confirmed this factor as the root cause, and we present data that show susceptibility of a class of cyanine dyes (e.g., Cy5, Alexa 647) to ozone levels as low as 5-10 ppb for periods as short as 10-30 s. Other cyanine dyes (e.g., Cy3, Alexa 555) were not significantly affected until higher ozone levels (> 100 ppb). To address this environmental effect, laboratory ozone levels should be kept below 2 ppb (e.g., with filters in HVAC) to achieve high quality microarray data.     

Robust dimensions of anxiety sensitivity: Development and initial validation of the Anxiety Sensitivity Index-3.

Accumulating evidence suggests that anxiety sensitivity (fear of arousal-related sensations) plays an important role in many clinical conditions, particularly anxiety disorders. Research has increasingly focused on how the basic dimensions of anxiety sensitivity are related to various forms of psychopathology. Such work has been hampered because the original measure--the Anxiety Sensitivity Index (ASI)--was not designed to be multidimensional. Subsequently developed multidimensional measures have unstable factor structures or measure only a subset of the most widely replicated factors. Therefore, the authors developed, via factor analysis of responses from U.S. and Canadian nonclinical participants (n = 2,361), an 18-item measure, the ASI-3, which assesses the 3 factors best replicated in previous research: Physical, Cognitive, and Social Concerns. Factorial validity of the ASI-3 was supported by confirmatory factor analyses of 6 replication samples, including nonclinical samples from the United States and Canada, France, Mexico, the Netherlands, and Spain (n = 4,494) and a clinical sample from the United States and Canada (n = 390). The ASI-3 displayed generally good performance on other indices of reliability and validity, along with evidence of improved psychometric properties over the original ASI. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

GENETIC ALGORITHM APPROACH TO A LUMBER CUTTING OPTIMIZATION PROBLEM

Genetic algorithms are a technique for search and optimization based on the Darwinian principle of natural selection. They are iterative search procedures that maintain a population of candidate solutions. The best or most fit solutions in that population are then used as the basis for the next generation of solutions. The next generation is formed using the genetic operators reproduction, crossover, and mutation. Genetic algorithms have been successfully applied to engineering search and optimization problems. This paper presents a discussion of the basic theory of genetic algorithms and presents a genetic algorithm solution of a lumber cutting optimization problem. Dimensional lumber is assigned a grade that represents its physical properties. A grade is assigned to every board segment of a specific length. The board is then cut in various locations in order to maximize its value, A genetic algorithm was used to determine the cutting patterns that would maximize the board value.     

Why are rocks pointy? Children's preference for teleological explanations of th natural world.

Teleological explanations are based on the assumption that an object or behavior exists for a purpose. Two studies explored the tendency of adults and first-, second-, and fourth-grade elementary-school children to explain the properties of living and nonliving natural kinds in teleological terms. Consistent with the hypothesis that young children possess a promiscuous teleological tendency, Study 1 found that children were more likely than adults to broadly examine the properties of both living and nonliving natural kinds in teleological terms, although the kinds of functions that they endorsed varied with age. Study 2 was an attempt to reduce children's broad teleological bias by introducing a pretrial that described, in nonteleological terms, the physical process by which nonliving natural kinds form. In spite of this attempt, Study 2 replicated the effects of Study 1, with only fourth graders showing any shift in preference for teleological explanation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparison of the reinforcing and anxiogenic effects of intravenous cocaine.

People report that ethanol improves the experience produced by cocaine. This effect may be attributable to cocaethylene (CE), a cocaine metabolite formed only in the presence of ethanol. To test this, rats were trained to run an alley for a single intravenous dose of either cocaine (0.5–2.0 mg/kg) or an equimolar dose of CE (0.75–2.88 mg/kg). The rats' start latency and running speed measured the reinforcing effects of the drugs and the number of times rats approached but failed to enter the goal box (i.e., approach-avoidance retreats) indexed anxiety. Rats reinforced with CE had shorter start latencies and faster running speeds and exhibited fewer "retreats" than cocaine-reinforced rats. These results suggest that CE is more reinforcing and less anxiogenic than cocaine and hence may account for the combined effects of cocaine and ethanol in humans. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Performance Measurement of Training in Engineering Organizations

This work introduces a new training program performance assessment methodology for engineering organizations that is based upon needs assessment, types of training, and training effectiveness measures. The methodology checks whether predefined objectives of a company are identified through a needs assessment. Effectiveness is judged on whether the types of training and coursework content are formulated to fulfill the needs assessment objectives, whether the coursework is available to the proper employees, whether the courses are attended and understood by the employees, and whether the coursework content is utilized in the work place to meet the needs assessment objectives of the company. A case study of three training programs conducted within a public sector engineering organization is included to demonstrate the methodology and evaluate both the three programs and the methodology effectiveness. Conclusions suggest improvements to future training programs for the public sector engineering organization, as well as describe potential enhancements to the effectiveness measures of the methodology that can be recognized through further study of existing training programs.     

Nature and nature in psychology.

This article explores the meanings of nature, and examines how understandings of this term inform the field of psychology. In this period of high, late, or post-modernity, many of the "givens" become contested, and perhaps nothing has become more contested than nature itself. There is a threefold purpose to this paper. This first goal is to unravel two types of nature in psychology, to be distinguished as nature and Nature. The second aim is to discuss how these types of nature/Nature have been distinguished epistemologically, ontologically and methodologically within the field. The final purpose is to suggest points of unity within nature and Nature in psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Self-help Housing as a Flexible Instrument of State Control in 20th-century South Africa

There is a long and varied usage of self-help housing policy in South Africa, dating from colonial times when Africans were dumped in locations and left to build their own housing, to the present post apartheid reconstruction. The paper documents and periodises the adoption of self-help strategies for housing the African population of South African cities throughout the 20th century. Exploration of the practice of self-help housing practices in Johannesburg suggests that owner construction is a prevailing method of social engineering, whose acceptance or rejection reflects perceived political and economic advantages for the state and the private sector, and is not a simple response to a shortage of affordable shelter among the poor.