Computer integrated laboratory testing

The objective is the integration of computers into the Engineering Materials Science Laboratory course, where existing test equipment is not computerized. The first lab procedure is to demonstrate and produce a material phase change curve. The second procedure is a demonstration of the modulus of elasticity and related stress-strain curve, plastic performance, maximum and failure strength. The process of recording data by sensors that are connected to a data logger which adds a time base, and the data logger in turn connected to a computer, places the materials labs into a computer integrated mode with minimum expense and maximum flexibility. The sensor signals are input into a spread sheet for tabular records, curve generation, and graph printing

Testing cosmological defect formation in the laboratory

Topological defects such as cosmic strings may have been formed at early-universe phase transitions. Direct tests of this idea are impossible, but the mechanism can be elucidated by studying analogous processes in low-temperature condensed-matter systems. Experiments on vortex formation in superfluid helium and in superconductors have so far yielded somewhat confusing results. I shall discuss their possible interpretation.Comment: 10 pages. Text of an invited lecture, to be published in Proceedings of the Second European Conference on Vortex Matter in Superconductors, Crete, 15-25 September 2001. Uses elsart.cls style fil

Automation software for a materials testing laboratory

A comprehensive software system for automating much of the experimental process has recently been completed at the Lewis Research Center's high-temperature fatigue and structures laboratory. The system was designed to support experiment definition and conduct, results analysis and archiving, and report generation activities. This was accomplished through the design and construction of several software systems, as well as through the use of several commercially available software products, all operating on a local, distributed minicomputer system. Experimental capabilities currently supported in an automated fashion include both isothermal and thermomechanical fatigue and deformation testing capabilities. The future growth and expansion of this system will be directed toward providing multiaxial test control, enhanced thermomechanical test control, and higher test frequency (hundreds of hertz)

Acute flaccid paralysis with anterior myelitis - California, June 2012-June 2014.

In August 2012, the California Department of Public Health (CDPH) was contacted by a San Francisco Bay area clinician who requested poliovirus testing for an unvaccinated man aged 29 years with acute flaccid paralysis (AFP) associated with anterior myelitis (i.e., evidence of inflammation of the spinal cord involving the grey matter including anterior horn cell bodies) and no history of international travel during the month before symptom onset. Within 2 weeks, CDPH had received reports of two additional cases of AFP with anterior myelitis of unknown etiology. Testing at CDPH's Viral and Rickettsial Disease Laboratory for stool, nasopharyngeal swab, and cerebrospinal fluid (CSF) did not detect the presence of an enterovirus (EV), the genus of the family Picornaviridae that includes poliovirus. Additional laboratory testing for infectious diseases conducted at the CDPH Viral and Rickettsial Disease Laboratory did not identify a causative agent to explain the observed clinical syndrome reported among the patients. To identify other cases of AFP with anterior myelitis and elucidate possible common etiologies, CDPH posted alerts in official communications for California local health departments during December 2012, July 2013, and February 2014. Reports of cases of neurologic illness received by CDPH were investigated throughout this period, and clinicians were encouraged to submit clinical samples for testing. A total of 23 cases of AFP with anterior myelitis of unknown etiology were identified. Epidemiologic and laboratory investigation did not identify poliovirus infection as a possible cause for the observed cases. No common etiology was identified to explain the reported cases, although EV-D68 was identified in upper respiratory tract specimens of two patients. EV infection, including poliovirus infection, should be considered in the differential diagnosis in cases of AFP with anterior myelitis and testing performed per CDC guidelines

Validation of a laboratory method for evaluating dynamic properties of reconstructed equine racetrack surfaces.

BackgroundRacetrack surface is a risk factor for racehorse injuries and fatalities. Current research indicates that race surface mechanical properties may be influenced by material composition, moisture content, temperature, and maintenance. Race surface mechanical testing in a controlled laboratory setting would allow for objective evaluation of dynamic properties of surface and factors that affect surface behavior.ObjectiveTo develop a method for reconstruction of race surfaces in the laboratory and validate the method by comparison with racetrack measurements of dynamic surface properties.MethodsTrack-testing device (TTD) impact tests were conducted to simulate equine hoof impact on dirt and synthetic race surfaces; tests were performed both in situ (racetrack) and using laboratory reconstructions of harvested surface materials. Clegg Hammer in situ measurements were used to guide surface reconstruction in the laboratory. Dynamic surface properties were compared between in situ and laboratory settings. Relationships between racetrack TTD and Clegg Hammer measurements were analyzed using stepwise multiple linear regression.ResultsMost dynamic surface property setting differences (racetrack-laboratory) were small relative to surface material type differences (dirt-synthetic). Clegg Hammer measurements were more strongly correlated with TTD measurements on the synthetic surface than the dirt surface. On the dirt surface, Clegg Hammer decelerations were negatively correlated with TTD forces.ConclusionsLaboratory reconstruction of racetrack surfaces guided by Clegg Hammer measurements yielded TTD impact measurements similar to in situ values. The negative correlation between TTD and Clegg Hammer measurements confirms the importance of instrument mass when drawing conclusions from testing results. Lighter impact devices may be less appropriate for assessing dynamic surface properties compared to testing equipment designed to simulate hoof impact (TTD).Potential relevanceDynamic impact properties of race surfaces can be evaluated in a laboratory setting, allowing for further study of factors affecting surface behavior under controlled conditions

A portable load cell for in-situ ore impact breakage testing

This paper discusses the design and characterisation of a short, and hence portable impact load cell for in-situ quantification of ore breakage properties under impact loading conditions. Much literature has been published in the past two decades about impact load cells for ore breakage testing. It has been conclusively shown that such machines yield significant quantitative energy-fragmentation information about industrial ores. However, documented load cells are all laboratory systems that are not adapted for in-situ testing due to their dimensions and operating requirements. The authors report on a new portable impact load cell designed specifically for in-situ testing. The load cell is 1.5 m in height and weighs 30 kg. Its physical and operating characteristics are detailed in the paper. This includes physical dimensions, calibration and signal deconvolution. Emphasis is placed on the deconvolution issue, which is significant for such a short load cell. Finally, it is conclusively shown that the short load cell is quantitatively as accurate as its larger laboratory analogues

The L1157-B1 astrochemical laboratory: testing the origin of DCN

L1157-B1 is the brightest shocked region of the large-scale molecular outflow, considered the prototype of chemically rich outflows, being the ideal laboratory to study how shocks affect the molecular gas. Several deuterated molecules have been previously detected with the IRAM 30m, most of them formed on grain mantles and then released into the gas phase due to the shock. We aim to observationally investigate the role of the different chemical processes at work that lead to formation the of DCN and test the predictions of the chemical models for its formation. We performed high-angular resolution observations with NOEMA of the DCN(2-1) and H13CN(2-1) lines to compute the deuterated fraction, Dfrac(HCN). We detected emission of DCN(2-1) and H13CN(2-1) arising from L1157-B1 shock. Dfrac(HCN) is ~4x10$^{-3}$ and given the uncertainties, we did not find significant variations across the bow-shock. Contrary to HDCO, whose emission delineates the region of impact between the jet and the ambient material, DCN is more widespread and not limited to the impact region. This is consistent with the idea that gas-phase chemistry is playing a major role in the deuteration of HCN in the head of the bow-shock, where HDCO is undetected as it is a product of grain-surface chemistry. The spectra of DCN and H13CN match the spectral signature of the outflow cavity walls, suggesting that their emission result from shocked gas. The analysis of the time dependent gas-grain chemical model UCL-CHEM coupled with a C-type shock model shows that the observed Dfrac(HCN) is reached during the post-shock phase, matching the dynamical timescale of the shock. Our results indicate that the presence of DCN in L1157-B1 is a combination of gas-phase chemistry that produces the widespread DCN emission, dominating in the head of the bow-shock, and sputtering from grain mantles toward the jet impact region.Comment: Accepted for publication in A&A. 7 pages, 5 Figures, 1 Tabl

Frequency of instrument, environment, and laboratory technologist contamination during routine diagnostic testing of infectious specimens

ABSTRACT Laboratory testing to support the care of patients with highly infectious diseases may pose a risk for laboratory workers. However, data on the risk of virus transmission during routine laboratory testing conducted using standard personal protective equipment (PPE) are sparse. Our objective was to measure laboratory contamination during routine analysis of patient specimens. Remnant specimens were spiked with the nonpathogenic bacteriophage MS2 at 1.0 × 10 7 PFU/ml, and contamination was assessed using reverse transcriptase PCR (RT-PCR) for MS2. Specimen containers were exteriorly coated with a fluorescent powder to enable the visualization of gross contamination using UV light. Testing was performed by two experienced laboratory technologists using standard laboratory PPE and sample-to-answer instrumentation. Fluorescence was noted on the gloves, bare hands, and laboratory coat cuffs of the laboratory technologist in 36/36 (100%), 13/36 (36%), and 4/36 (11%) tests performed, respectively. Fluorescence was observed in the biosafety cabinet (BSC) in 8/36 (22%) tests, on test cartridges/devices in 14/32 (44%) tests, and on testing accessory items in 29/32 (91%) tests. Fluorescence was not observed on or in laboratory instrumentation or adjacent surfaces. In contrast to fluorescence detection, MS2 detection was infrequent (3/286 instances [1%]) and occurred during test setup for the FilmArray instrument and on FilmArray accessory equipment. The information from this study may provide opportunities for the improvement of clinical laboratory safety practices so as to reduce the risk of pathogen transmission to laboratory workers. </jats:p