3,443 research outputs found
Development of a Long-Period Torsion Balance for Tests of Einstein\u27s Equivalence Principle and a Search for Normal Mode Torsional Oscillations of the Earth
This thesis describes the development of a torsion balance experiment designed to test Einstein\u27s equivalence principle with unprecedented sensitivity, while also taking a novel approach to directly observe the normal mode torsional oscillations of the Earth. Accordingly, a model of the signal expected from a potential equivalence principle violation has been developed, as well as a multi-slit auto-collimating optical lever which possesses a resolution on the order of a nanoradian and a range of observation of 10 milliradians and is used to monitor the torsion balance. A torsion balance with a natural torsional frequency of ~104 Hz, signi_cantly below the frequency of the longest of the Earth\u27s normal modes, was designed, built, and operated in a remote laboratory at Washington University\u27s Tyson Research Center. More than 1800 hours of data was collected and used to evaluate the performance of this prototype instrument and characterize the conditions in the Tyson laboratory
Industry-Government Collaboration: Queensland \u27s IT&T Strategy and the Information Industries Board
This paper presents a field study of the Queensland Information Technology and Telecommunications Industry Strategy (QITIS), and of the Information Industries Board (IIB), a joint industry-state government body established in 1992 to oversee the implementation of that strategy for the development of the IT&T Industry in Queensland. The aim of the study was to analyse differing stakeholder perspectives on the strategy and on its implementation by the IIB. The study forms part of a longer-term review which aims to develop methodologies for the selection of appropriate strategies for the IT&T Industry, and for the evaluation of outcomes of strategy
Managing for change: October 11, 1989
Bi-weekly newsletter of University Hospital's Change Project, provided to managers at the hospital
Using mixed methods for analysing culture : The Cultural Capital and Social Exclusion project
This paper discusses the use of material generated in a mixed method investigation into cultural tastes and practices, conducted in Britain from 2003 to 2006, which employed a survey, focus groups and household interviews. The study analysed the patterning of cultural life across a number of fields, enhancing the empirical and methodological template provided by Bourdieu’s Distinction. Here we discuss criticisms of Bourdieu emerging from subsequent studies of class, culture and taste, outline the arguments related to the use of mixed methods and present illustrative results from the analysis of these different types of data. We discuss how the combination of quantitative and qualitative methods informed our analysis of cultural life in contemporary Britain. No single method was able to shed light on all aspects of our inquiry, lending support to the view that mixing methods is the most productive strategy for the investigation of complex social phenomena
Very bright orange fluorescent plants: endoplasmic reticulum targeting of orange fluorescent proteins as visual reporters in transgenic plants
Background
The expression of fluorescent protein (FP) genes as real-time visual markers, both transiently and stably, has revolutionized plant biotechnology. A palette of colors of FPs is now available for use, but the diversity has generally been underutilized in plant biotechnology. Because of the green and far-red autofluorescent properties of many plant tissues and the FPs themselves, red and orange FPs (RFPs, and OFPs, respectfully) appear to be the colors with maximum utility in plant biotechnology. Within the color palette OFPs have emerged as the brightest FP markers in the visible spectra. This study compares several native, near-native and modified OFPs for their “brightness” and fluorescence, therefore, their usability as marker genes in transgenic plant tissues. Results
The OFPs DsRed2, tdTomato, mOrange and pporRFP were all expressed under the control of the CaMV 35S promoter in agroinfiltration-mediated transient assays in Nicotiana benthamiana. Each of these, as well as endoplasmic reticulum (ER)-targeted versions, were stably expressed in transgenic Nicotiana tabacum and Arabidopsis thaliana. Congruent results were observed between transient and stable assays. Our results demonstrated that there are several adequate OFP genes available for plant transformation, including the new pporRFP, an unaltered tetramer from the hard coral Porites porites. When the tandem dimer tdTomato and the monomeric mOrange were targeted to the ER, dramatic, ca. 3-fold, increase in plant fluorescence was observed. Conclusions
From our empirical data, and a search of the literature, it appears that tdTomato-ER and mOrange-ER are the two highest fluorescing FPs available as reporters for transgenic plants. The pporRFP is a brightly fluorescing tetramer, but all tetramer FPs are far less bright than the ER-targeted monomers we report here
Local seismicity around the Chain Transform Fault at the Mid-Atlantic Ridge from OBS observations
Summary
Seismicity along transform faults provides important constraints for our understanding of the factors that control earthquake ruptures. Oceanic transform faults are particularly informative due to their relatively simple structure in comparison to their continental counterparts. The seismicity of several fast-moving transform faults has been investigated by local networks, but as of today there been few studies of transform faults in slow spreading ridges. Here we present the first local seismicity catalogue based on event data recorded by a temporary broadband network of 39 ocean bottom seismometers located around the slow-moving Chain Transform Fault (CTF) along the Mid-Atlantic Ridge (MAR) from March 2016 to March 2017. We locate 972 events in the area by simultaneously inverting for a 1-D velocity model informed by the event P- and S-arrival times. We refine the depths and focal mechanisms of the larger events using deviatoric moment tensor inversion. Most of the earthquakes are located along the CTF (700) and Romanche transform fault (94) and the MAR (155); a smaller number (23) can be observed on the continuing fracture zones or in intraplate locations. The ridge events are characterised by normal faulting and most of the transform events are characterised by strike slip faulting, but with several reverse mechanisms that are likely related to transpressional stresses in the region. CTF events range in magnitude from 1.1 to 5.6 with a magnitude of completeness around 2.3. Along the CTF we calculate a b-value of 0.81 ± 0.09. The event depths are mostly shallower than 15 km below sea level (523), but a small number of high-quality earthquakes (16) are located deeper, with some (8) located deeper than the brittle-ductile transition as predicted by the 600˚C-isotherm from a simple thermal model. The deeper events could be explained by the control of seawater infiltration on the brittle failure limit
Pleasure and meaningful discourse: an overview of research issues
The concept of pleasure has emerged as a multi-faceted social and cultural phenomenon in studies of media audiences since the 1980s. In these studies different forms of pleasure have been identified as explaining audience activity and commitment. In the diverse studies pleasure has emerged as a multi-faceted social and cultural concept that needs to be contextualized carefully. Genre and genre variations, class, gender, (sub-)cultural identity and generation all seem to be instrumental in determining the kind and variety of pleasures experienced in the act of viewing. This body of research has undoubtedly contributed to a better understanding of the complexity of audience activities, but it is exactly the diversity of the concept that is puzzling and poses a challenge to its further use. If pleasure is maintained as a key concept in audience analysis that holds much explanatory power, it needs a stronger theoretical foundation. The article maps the ways in which the concept of pleasure has been used by cultural theorists, who have paved the way for its application in reception analysis, and it goes on to explore the ways in which the concept has been used in empirical studies. Central to our discussion is the division between the ‘public knowledge’ and the ‘popular culture’ projects in reception analysis which, we argue, have major implications for the way in which pleasure has come to be understood as divorced from politics, power and ideology. Finally, we suggest ways of bridging the gap between these two projects in an effort to link pleasure to the concepts of hegemony and ideology
Elastic deformation of a fluid membrane upon colloid binding
When a colloidal particle adheres to a fluid membrane, it induces elastic
deformations in the membrane which oppose its own binding. The structural and
energetic aspects of this balance are theoretically studied within the
framework of a Helfrich Hamiltonian. Based on the full nonlinear shape
equations for the membrane profile, a line of continuous binding transitions
and a second line of discontinuous envelopment transitions are found, which
meet at an unusual triple point. The regime of low tension is studied
analytically using a small gradient expansion, while in the limit of large
tension scaling arguments are derived which quantify the asymptotic behavior of
phase boundary, degree of wrapping, and energy barrier. The maturation of
animal viruses by budding is discussed as a biological example of such
colloid-membrane interaction events.Comment: 14 pages, 9 figures, REVTeX style, follow-up on cond-mat/021242
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Prototype Weigh-In-Motion Performance
Oak Ridge National Laboratory (ORNL) has developed and patented methods to weigh slowly moving vehicles. We have used this technology to produce a portable weigh-in-motion system that is robust and accurate. This report documents the performance of the second-generation portable weigh-in-motion prototype (WIM Gen II). The results of three modes of weight determination are compared in this report: WIM Gen II dynamic mode, WIM Gen II stop-and-go mode, and static (parked) mode on in-ground, static scales. The WIM dynamic mode measures axle weights as the vehicle passes over the system at speeds of 3 to 7 miles per hour (1.3 to 3.1 meters/second). The WIM stop-and-go mode measures the weight of each axle of the vehicle as the axles are successively positioned on a side-by-side pair of WIM measurement pads. In both measurement modes the center of balance (CB) and the total weight are obtained by a straight-forward calculation from axle weights and axle spacings. The performance metric is measurement error (in percent), which is defined as 100 x (sample standard deviation)/(average); see Appendix A for details. We have insufficient data to show that this metric is predictive. This report details the results of weight measurements performed in May 2005 at two sites using different types of vehicles at each site. In addition to the weight measurements, the testing enabled refinements to the test methodology and facilitated an assessment of the influence of vehicle speed on the dynamic-mode measurements. The initial test at the National Transportation Research Center in Knoxville, TN, involved measurements of passenger and light-duty commercial vehicles. A subsequent test at the Arrival/Departure Airfield Control Group (A/DACG) facility in Ft. Bragg, NC, involved military vehicles with gross weights between 3,000 and 75,000 pounds (1,356 to 33,900 kilograms) with a 20,000-pound (9,040 kilograms) limit per axle. For each vehicle, four or more separate measurements were done using each weighing mode. WIM dynamic, WIM stop-and-go, and static-mode scale measurements were compared for total vehicle weight and the weight of the individual axles. We made WIM dynamic mode measurements with three assemblages of weight-transducer pads to assess the performance with varying numbers (2, 4, and 6) of weigh pads. Percent error in the WIM dynamic mode was 0.51%, 0.37%, and 0.37% for total vehicle weight and 0.77%, 0.50%, and 0.47% for single-axle weight for the two-, four-, and six-pad systems, respectively. Errors in the WIM stop-and-go mode were 0.55% for total vehicle weight and 0.62% for single-axle weights. In-ground scales weighed these vehicles with an error of 0.04% (within Army specifications) for total vehicle weight, and an error of 0.86% for single-axle weight. These results show that (1) the WIM error in single-axle weight was less than that obtained from in-ground static scales; (2) the WIM system eliminates time-consuming manual procedures, human errors, and safety concerns; and (3) measurement error for the WIM prototype was less than 1% (within Army requirements for this project). All the tests were performed on smooth, dry, level, concrete surfaces. Tests under non-ideal surface conditions are needed (e.g., rough but level, sun-baked asphalt, wet pavement), and future work will test WIM performance under these conditions. However, we expect the performance will be as good as, if not better than, the present WIM performance. We recommend the WIM stop-and-go mode under non-ideal surface conditions. We anticipate no performance degradation, assuming no subsurface deformation occurs
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