394 research outputs found

    Archaeological Reconnaissance of a Proposed Fill Site in Mitchell, Lawrence County, Indiana

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    Abstracts are made available for research purposes. To view the full report, please contact the staff of the Glenn A. Black Laboratory of Archaeology (www.gbl.indiana.edu).At the request of Burton Family Bus Sales (BFBS), the Glenn A. Black Laboratory of Archaeology, Indiana University (GBL) performed a cultural resources survey of the location for a proposed spoil dumping site in Mitchell, Lawrence County, Indiana. Specifically, the project area will be filled with broken pavement, large rocks, and clean fill resulting from construction of S. R. 37 through Mitchell. After highway construction is complete, the property will be graded for a new parking lot and a crushed stone surface will be laid. A total of approximately 12 acres was surveyed. The purposes of the survey were 1) to identify and document all of the cultural resources in the project area, 2) to evaluate any sites with regard to their eligibility for inclusion on the National Register of Historic Places (NRHP) and the Indiana Register of Historic Sites and Structures (IRHSS), and 3) to make recommendations for the protection of significant and potentially significant sites. Fieldwork was conducted July 1, 1999 by GBL archaeologist Patrick K. O'Brien. The entire project area had been previously used for many years as a parking lot for school buses. Approximately 4 acres along the west edge of the property is heavily eroded, with the terra rossa subsoil fully exposed in most places. About another 4 acres in the central portion of the project area can be characterized as a topographic low. At the time of fieldwork, much of this area contained standing water. The eastern edge and south end of the project area is perhaps the least disturbed area. However, the entire property has been covered with 20 cm to 30 cm of crushed stone and has undergone parking lot maintenance for at least two decades. Several probes through this parking surface revealed that it has been extremely compacted. No cultural materials were discovered during survey and there is little to no potential for intact subsurface cultural materials in the project area. Cultural resource clearance is recommended for the project area

    Active control of aircraft engine inlet noise using compact sound sources and distributed error sensors

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    An active noise control system using a compact sound source is effective to reduce aircraft engine duct noise. The fan noise from a turbofan engine is controlled using an adaptive filtered-x LMS algorithm. Single multi channel control systems are used to control the fan blade passage frequency (BPF) tone and the BPF tone and the first harmonic of the BPF tone for a plane wave excitation. A multi channel control system is used to control any spinning mode. The multi channel control system to control both fan tones and a high pressure compressor BPF tone simultaneously. In order to make active control of turbofan inlet noise a viable technology, a compact sound source is employed to generate the control field. This control field sound source consists of an array of identical thin, cylindrically curved panels with an inner radius of curvature corresponding to that of the engine inlet. These panels are flush mounted inside the inlet duct and sealed on all edges to prevent leakage around the panel and to minimize the aerodynamic losses created by the addition of the panels. Each panel is driven by one or more piezoelectric force transducers mounted on the surface of the panel. The response of the panel to excitation is maximized when it is driven at its resonance; therefore, the panel is designed such that its fundamental frequency is near the tone to be canceled, typically 2000-4000 Hz

    Active control of aircraft engine inlet noise using compact sound sources and distributed error sensors

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    An active noise control system using a compact sound source is effective to reduce aircraft engine duct noise. The fan noise from a turbofan engine is controlled using an adaptive filtered-x LMS algorithm. Single multi channel control systems are used to control the fan blade passage frequency (BPF) tone and the BPF tone and the first harmonic of the BPF tone for a plane wave excitation. A multi channel control system is used to control any spinning mode. The multi channel control system to control both fan tones and a high pressure compressor BPF tone simultaneously. In order to make active control of turbofan inlet noise a viable technology, a compact sound source is employed to generate the control field. This control field sound source consists of an array of identical thin, cylindrically curved panels with an inner radius of curvature corresponding to that of the engine inlet. These panels are flush mounted inside the inlet duct and sealed on all edges to prevent leakage around the panel and to minimize the aerodynamic losses created by the addition of the panels. Each panel is driven by one or more piezoelectric force transducers mounted on the surface of the panel. The response of the panel to excitation is maximized when it is driven at its resonance; therefore, the panel is designed such that its fundamental frequency is near the tone to be canceled, typically 2000-4000 Hz

    Hydrographic Changes in Nares Strait (Canadian Arctic Archipelago) in Recent Decades Based on δ18O Profiles of Bivalve Shells

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    Nares Strait is one of three main passages of the Canadian Archipelago that channel relatively fresh seawater from the Arctic Ocean through Baffin Bay to the Labrador Sea. Oxygen isotopic profiles along the growth axis of bivalve shells, collected live over the 5 – 30 m depth range from the Greenland and Ellesmere Island sides of the strait, were used to reconstruct changes in the hydrography of the region over the past century. The variability in oxygen isotope ratios is mainly attributed to variations in salinity and suggests that the northern end of Nares Strait has been experiencing an increase in freshwater runoff since the mid 1980s. The recent changes are most pronounced at the northern end of the strait and diminish toward the south, a pattern consistent with proximity to the apparently freshening Arctic Ocean source in the north and mixing with Baffin Bay waters as the water progresses southward. This increasing freshwater signal may reflect changes in circulation and ice formation that favor an increased flow of relatively fresh waters from the Arctic Ocean into Nares Strait.Le détroit de Nares est l’un des trois principaux passages de l’archipel canadien qui canalise de l’eau de mer relativement fraîche de l’océan Arctique jusqu’à la mer du Labrador en passant par la baie de Baffin. Les profils de la composition isotopique de l’oxygène le long de l’axe de développement des coquillages bivalves recueillis en vie à une profondeur variant entre 5 à 30 m des côtés du détroit à la hauteur du Groenland et de l’île d’Ellesmere ont servi à reconstruire les changements ayant caractérisé l’hydrographie de la région au cours du dernier siècle. La variabilité en matière de ratio d’isotope de l’oxygène est principalement attribuable aux variations de salinité, ce qui laisse entendre que l’extrémité nord du détroit de Nares connaît une augmentation de l’écoulement d’eau douce depuis le milieu des années 1980. Les changements récents sont plus prononcés à l’extrémité nord du détroit et diminuent en arrivant vers le sud, ce qui constitue une tendance conforme à la proximité de la source de l’océan Arctique en dessalure apparente dans le nord et qui se mélange avec les eaux de la baie de Baffin au fur et à mesure que l’eau progresse vers le sud. Cette augmentation de la présence d’eau douce peut être le reflet de changements en matière de circulation et de formation de la glace qui favorisent un écoulement accru d’eaux relativement douces en provenance de l’océan Arctique et se jettent dans le détroit de Nares

    Primary care physicians’ perspectives on computer-based health risk assessment tools for chronic diseases: a mixed methods study

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    Background Health risk assessment tools compute an individual’s risk of developing a disease. Routine use of such tools by primary care physicians (PCPs) is potentially useful in chronic disease prevention. We sought physicians’ awareness and perceptions of the usefulness, usability and feasibility of performing assessments with computer-based risk assessment tools in primary care settings.Methods Focus groups and usability testing with a computer-based risk assessment tool were conducted with PCPs from both university-affiliated and community-based practices. Analysis was derived from grounded theory methodology.Results PCPs (n = 30) were aware of several risk assessment tools although only select tools were used routinely. The decision to use a tool depended on how use impacted practice workflow and whether the tool had credibility. Participants felt that embedding tools in the electronic medical records (EMRs) system might allow for health information from the medical record to auto-populate into the tool. User comprehension of risk could also be improved with computer-based interfaces that present risk in different formats.Conclusions In this study, PCPs chose to use certain tools more regularly because of usability and credibility. Despite there being differences in the particular tools a clinical practice used, there was general appreciation for the usefulness of tools for different clinical situations. Participants characterised particular features of an ideal tool, feeling strongly that embedding risk assessment tools in the EMR would maximise accessibility and use of the tool for chronic disease management. However, appropriate practice workflow integration and features that facilitate patient understanding at point-of-care are also essential.

    Evaluation of diffusion-weighted MRI and (18F) fluorothymidine-PET biomarkers for early response assessment in patients with operable non-small cell lung cancer treated with neoadjuvant chemotherapy

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    Objective: To correlate changes in the apparent diffusion coefficient (ADC) from diffusion-weighted (DW)-MRI and standardised uptake value (SUV) from fluorothymidine (18FLT)-PET/CT with histopathological estimates of response in patients with non-small cell lung cancer (NSCLC) treated with neoadjuvant chemotherapy and track longitudinal changes in these biomarkers in a multicentre, multivendor setting. Methods: 14 patients with operable NSCLC recruited to a prospective, multicentre imaging trial (EORTC-1217) were treated with platinum-based neoadjuvant chemotherapy. 13 patients had DW-MRI and FLT-PET/CT at baseline (10 had both), 12 were re-imaged at Day 14 (eight dual-modality) and nine after completing chemotherapy, immediately before surgery (six dual-modality). Surgical specimens (haematoxylin-eosin and Ki67 stained) estimated the percentage of residual viable tumour/necrosis and proliferation index. Results: Despite the small numbers,significant findings were possible. ADCmedian increased (p 30% reduction in unidimensional measurement pre-surgery), showed an increase at Day 14 in ADC75th centile and reduction in total lesion proliferation (SUVmean x proliferative volume) greater than established measurement variability. Change in imaging biomarkers did not correlate with histological response (residual viable tumour, necrosis). Conclusion: Changes in ADC and FLT-SUV following neoadjuvant chemotherapy in NSCLC were measurable by Day 14 and preceded changes in unidimensional size but did not correlate with histopathological response. However, the magnitude of the changes and their utility in predicting (non-) response (tumour size/clinical outcome) remains to be established. Advances in knowledge: During treatment, ADC increase precedes size reductions, but does not reflect histopathological necrosis
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