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• 1431. [Article] The partial purification-characterization of bean yellow mosaic virus

  Factors limiting effective extraction and purification of bean yellow mosaic virus (BYMV) were investigated. Since the use of published techniques for purifying BYMV resulted in low yields of partially purified ...

  Citation × Citation Citation Abstract Copy Title: The partial purification-characterization of bean yellow mosaic virus Author: Chairez, Ruben, 1942-, Chairez, Ruben Factors limiting effective extraction and purification of bean yellow mosaic virus (BYMV) were investigated. Since the use of published techniques for purifying BYMV resulted in low yields of partially purified virus, an improved method for partial purification of this virus was developed. The following treatments of infectious crude extract decreased infectivity: (i) mechanical rupture of the chloroplasts, (ii) homogenization in anionic, nonionic, or cationic surfactants, (iii) addition of the organic solvents acetone, butanol, ethanol, methanol, petroleum ether, diethyl ether, toluene, and chloroform, (iv) centrifugation in high salt concentrations (KBr or CsCl), (v) zone electrophoresis, (vi) homogenization in ethylenedinitrila-tetra acetic acid (EDTA) or in thioglycollic acid. The following treatments increased infectivity of the crude extract when added to the homogenizing medium: (i) 0.1M KCI, (ii) beta-mercaptoethanol, (iii) urea. Chenopodium amarantciolor, a local lesion host of BYMV, yielded more virus than the systemically infected hosts evaluated. Virus los. by sedimentation occurred during initial low-speed centrifugation of the crude extract from systemically infected hosts. Relatively little infectivity was lost from C. amaranticolor crude extract during low-speed centrifugation. Of four severe BYMV isolates tested, isolate 724 yielded the highest amount of partially purified virus. Use of isolate 724 cultured in C. amaranticolor resulted in a high yield of extractable virus. The best buffer for homogenizing BYMV-infected C. amaranticolor tissue was 0. 05M diphosphate, 0.1M KC1 within the pH range 8.5-9.0. Re-extraction from pulp increased the total amount of virus extracted from C. amaranticolor by 30 percent. Preliminary clarification of crude extract was achieved by a low-speed centrifugation followed by a moderate-speed centrifugation. The following treatments decreased yield of partially purified virus: (i) heating or freezing of the crude extract, (ii) acidification (pH 3, 3.5, 4, 4.5, 5, 5.5, 6) of the crude extract, (iii) addition of 0.25 saturated (NH₄)₂SO₄ to the clarified supernatant, (iv) clarification by the ether-carbon tetrachloride method, and (v) homogenization of infected tissue in bentonite. Homogenization in 0.45-0.90M sucrose yielded an infectious high-speed pellet, and an infectious density-gradient fraction, but poor clarification. Absorbancy profiles and infectivity of density-gradient (DG) fractions showed that the polyethylene glycol (PEG) treatment yielded less host contaminants and better banding of partially purified virus in the DG column than did the bentonite, sucrose, or ether-carbon tetrachloride treatments. Sepharose gel filtration or zone electrophoresis of infectious, concentrated PEG extract did not result in further purification. Zonal rotor centrifugation of clarified supernatant resulted in a concentration of BYMV into a narrow band, but the virus sample was still impure. DG centrifugation of the infectious, concentrated PEG extract was the best purification method. The most highly purified fraction occurred 12-16 mm below the meniscus of the DG column. Electron microscopy showed that the modal length of the virus particles directly from local lesions was 750 nm, while the modal length of particles in the most purified DG fraction was 680 nm. The most highly purified BYMV preparation obtainable had an ultraviolet absorption spectrum typical of anisometric viruses and a 260/280 ratio of 1.152. The sedimentation coefficient of the most infectious DG fraction was 2050.5 S. This large value indicated that particle aggregation occurred. Title: The partial purification-characterization of bean yellow mosaic virus Author: Chairez, Ruben, 1942-, Chairez, Ruben Factors limiting effective extraction and purification of bean yellow mosaic virus (BYMV) were investigated. Since the use of published techniques for purifying BYMV resulted in low yields of partially purified virus, an improved method for partial purification of this virus was developed. The following treatments of infectious crude extract decreased infectivity: (i) mechanical rupture of the chloroplasts, (ii) homogenization in anionic, nonionic, or cationic surfactants, (iii) addition of the organic solvents acetone, butanol, ethanol, methanol, petroleum ether, diethyl ether, toluene, and chloroform, (iv) centrifugation in high salt concentrations (KBr or CsCl), (v) zone electrophoresis, (vi) homogenization in ethylenedinitrila-tetra acetic acid (EDTA) or in thioglycollic acid. The following treatments increased infectivity of the crude extract when added to the homogenizing medium: (i) 0.1M KCI, (ii) beta-mercaptoethanol, (iii) urea. Chenopodium amarantciolor, a local lesion host of BYMV, yielded more virus than the systemically infected hosts evaluated. Virus los. by sedimentation occurred during initial low-speed centrifugation of the crude extract from systemically infected hosts. Relatively little infectivity was lost from C. amaranticolor crude extract during low-speed centrifugation. Of four severe BYMV isolates tested, isolate 724 yielded the highest amount of partially purified virus. Use of isolate 724 cultured in C. amaranticolor resulted in a high yield of extractable virus. The best buffer for homogenizing BYMV-infected C. amaranticolor tissue was 0. 05M diphosphate, 0.1M KC1 within the pH range 8.5-9.0. Re-extraction from pulp increased the total amount of virus extracted from C. amaranticolor by 30 percent. Preliminary clarification of crude extract was achieved by a low-speed centrifugation followed by a moderate-speed centrifugation. The following treatments decreased yield of partially purified virus: (i) heating or freezing of the crude extract, (ii) acidification (pH 3, 3.5, 4, 4.5, 5, 5.5, 6) of the crude extract, (iii) addition of 0.25 saturated (NH₄)₂SO₄ to the clarified supernatant, (iv) clarification by the ether-carbon tetrachloride method, and (v) homogenization of infected tissue in bentonite. Homogenization in 0.45-0.90M sucrose yielded an infectious high-speed pellet, and an infectious density-gradient fraction, but poor clarification. Absorbancy profiles and infectivity of density-gradient (DG) fractions showed that the polyethylene glycol (PEG) treatment yielded less host contaminants and better banding of partially purified virus in the DG column than did the bentonite, sucrose, or ether-carbon tetrachloride treatments. Sepharose gel filtration or zone electrophoresis of infectious, concentrated PEG extract did not result in further purification. Zonal rotor centrifugation of clarified supernatant resulted in a concentration of BYMV into a narrow band, but the virus sample was still impure. DG centrifugation of the infectious, concentrated PEG extract was the best purification method. The most highly purified fraction occurred 12-16 mm below the meniscus of the DG column. Electron microscopy showed that the modal length of the virus particles directly from local lesions was 750 nm, while the modal length of particles in the most purified DG fraction was 680 nm. The most highly purified BYMV preparation obtainable had an ultraviolet absorption spectrum typical of anisometric viruses and a 260/280 ratio of 1.152. The sedimentation coefficient of the most infectious DG fraction was 2050.5 S. This large value indicated that particle aggregation occurred. Close

• 1432. [Article] An investigation into the electrochemical removal of unwanted residual material protrusions from parts

  Manuscript I: The removal of residual casting material from gating has traditionally been performed by abrasive grinding techniques. However, high amounts of belt wear can occur when working with high ...

  Citation × Citation Citation Abstract Copy Title: An investigation into the electrochemical removal of unwanted residual material protrusions from parts Author: Bingham, Bruce C. Manuscript I: The removal of residual casting material from gating has traditionally been performed by abrasive grinding techniques. However, high amounts of belt wear can occur when working with high strength alloys, especially those typically seen in the aerospace industry. An alternative machining process called electrochemical machining (ECM) uses electrolysis to precisely remove material at high rates. ECM has many advantages over conventional grinding: no tool wear, no induced mechanical or thermal stresses, and high removal rates independent of material hardness or strength. The industrial application of ECM to residual casting material removal can potentially realize large cost savings and decreased component processing time by eliminating belt wear and increasing material removal rates. The approach taken in this work is the design and fabrication of a laboratory apparatus for the purpose of testing the ECM of casting material. Commercial ECM machines, while more powerful, can be excessively large and cost prohibitive when performing an initial feasibility study. Many times these commercial machines are calibrated to mass produce a specific part, and do not have the level of variability desired for laboratory experimentation. The test apparatus presented provides a robust and relatively low cost method of investigating the applicability of ECM to this purpose. The device is comprised of an electrolyte filtration and delivery system, a stable machining enclosure, and a single axis computer controlled tool. The ECM variables that can be adjusted include electrolyte temperature, mass flow rate, applied voltage, tool feed rate, and electrode gap. Process data from these variables is collected via multiple sensors in the machine and provides real-time feedback to users. A universal tool connection and workpiece fixture allows for different experimental setups to be easily tested. From experimentation with this test apparatus, it will be possible to identify optimum methods for the ECM of these residual casting artifacts. Manuscript II: Rapid tool wear can occur during the removal of residual protrusions from high strength alloy parts. In this work, a new method of using electrochemical machining (ECM) capsules to remove protrusions without any tool wear is presented. An ECM capsule is an electrochemical cell that is placed on a part over a protrusion, and removes material through electrolysis. These capsules are advantageous due to their low cost and simplicity compared to conventional ECM equipment. The use of these capsules is demonstrated in two ways. First, a parameter optimization was performed on the material removal rates of Inconel 718 and Titanium 6-4 bar stock using a 2⁸⁻⁴ fractional factorial design of experiments. Then, using the optimized values, torch-cut protrusions were machined off of manufactured Titanium 6-4 parts. Inherent variability in the geometry of the protrusions rendered it difficult to completely remove the protrusions without cutting into the part. Surface scans of the parts showed that the capsules were able to successfully remove between 63% and 80% of each protrusion. Properly integrated into a protrusion removal operation, these ECM capsules could offer significant cost savings due to their ability to machine protrusions with no incurred tool wear. Title: An investigation into the electrochemical removal of unwanted residual material protrusions from parts Author: Bingham, Bruce C. Manuscript I: The removal of residual casting material from gating has traditionally been performed by abrasive grinding techniques. However, high amounts of belt wear can occur when working with high strength alloys, especially those typically seen in the aerospace industry. An alternative machining process called electrochemical machining (ECM) uses electrolysis to precisely remove material at high rates. ECM has many advantages over conventional grinding: no tool wear, no induced mechanical or thermal stresses, and high removal rates independent of material hardness or strength. The industrial application of ECM to residual casting material removal can potentially realize large cost savings and decreased component processing time by eliminating belt wear and increasing material removal rates. The approach taken in this work is the design and fabrication of a laboratory apparatus for the purpose of testing the ECM of casting material. Commercial ECM machines, while more powerful, can be excessively large and cost prohibitive when performing an initial feasibility study. Many times these commercial machines are calibrated to mass produce a specific part, and do not have the level of variability desired for laboratory experimentation. The test apparatus presented provides a robust and relatively low cost method of investigating the applicability of ECM to this purpose. The device is comprised of an electrolyte filtration and delivery system, a stable machining enclosure, and a single axis computer controlled tool. The ECM variables that can be adjusted include electrolyte temperature, mass flow rate, applied voltage, tool feed rate, and electrode gap. Process data from these variables is collected via multiple sensors in the machine and provides real-time feedback to users. A universal tool connection and workpiece fixture allows for different experimental setups to be easily tested. From experimentation with this test apparatus, it will be possible to identify optimum methods for the ECM of these residual casting artifacts. Manuscript II: Rapid tool wear can occur during the removal of residual protrusions from high strength alloy parts. In this work, a new method of using electrochemical machining (ECM) capsules to remove protrusions without any tool wear is presented. An ECM capsule is an electrochemical cell that is placed on a part over a protrusion, and removes material through electrolysis. These capsules are advantageous due to their low cost and simplicity compared to conventional ECM equipment. The use of these capsules is demonstrated in two ways. First, a parameter optimization was performed on the material removal rates of Inconel 718 and Titanium 6-4 bar stock using a 2⁸⁻⁴ fractional factorial design of experiments. Then, using the optimized values, torch-cut protrusions were machined off of manufactured Titanium 6-4 parts. Inherent variability in the geometry of the protrusions rendered it difficult to completely remove the protrusions without cutting into the part. Surface scans of the parts showed that the capsules were able to successfully remove between 63% and 80% of each protrusion. Properly integrated into a protrusion removal operation, these ECM capsules could offer significant cost savings due to their ability to machine protrusions with no incurred tool wear. Close

• 1433. [Article] Tidal-band and high-frequency internal variability on the central Oregon inner shelf

  Analogous to ocean surface waves, waves in the ocean interior also experience steepening, breaking, and dissipation as they approach the coastline. Much less is known about this internal beach. In this ...

  Citation × Citation Citation Abstract Copy Title: Tidal-band and high-frequency internal variability on the central Oregon inner shelf Author: Suanda, Sutara H. Analogous to ocean surface waves, waves in the ocean interior also experience steepening, breaking, and dissipation as they approach the coastline. Much less is known about this internal beach. In this work, extensive moored Acoustic Doppler Current Profiler and temperature/salinity data together with optical remote sensing are combined to describe and understand tidal-band and high-frequency internal wave propagation over the Oregon mid and inner shelf. Semidiurnal baroclinic velocity is dominated by the first mode at all locations, with larger velocities on the mid shelf and northern part of a large submarine bank. Mid-shelf sites have baroclinic ellipticity that is near the theoretical value for single, progressive internal tidal waves compared to more linearly polarized currents over the inner shelf. Temporal variability does not correspond to the spring-neap cycle and is overall uncorrelated between mooring locations due to variable along-shelf topography and stratification. An idealized model of two amplitude-modulated internal waves propagating from different directions reproduces some of the observed variability in inner-shelf semidiurnal ellipse parameters. Moored observations were combined with sea-surface imagery to describe the propagation of 11 bore-like internal waves across the inner shelf. The surface expression of these waves is identified by regions of increased pixel intensity during wind speeds between 2 - 5 m/s⁻¹. Optical measurements show that internal waves are refracted by bathymetry, and measured wave speed (~0.15 m/s) is higher than predicted by linear theory (< 0.1 m/s⁻¹). The number and strength of these high-frequency (15 minute period), highly nonlinear features are linked to regional-scale upwelling/downwelling as well as the phase of the mid-shelf internal tide. In general, both surface and bottom-trapped bores are observed on the inner shelf and their polarity can be predicted by the weakly nonlinear parameter of the Korteweg-de Vries wave propagation equation. These bores have different consequences for the amount of horizontal transport they accomplish and where in the water column this transport occurs. The transformation of the internal tide impacts the form of the nonlinear high-frequency oscillations observed on the inner shelf. The most efficient onshore transport of sub-thermocline water is observed during a shallow mid-shelf pycnocline with large mid-shelf semidiurnal displacement that results in only elevation waves onshore. Title: Tidal-band and high-frequency internal variability on the central Oregon inner shelf Author: Suanda, Sutara H. Analogous to ocean surface waves, waves in the ocean interior also experience steepening, breaking, and dissipation as they approach the coastline. Much less is known about this internal beach. In this work, extensive moored Acoustic Doppler Current Profiler and temperature/salinity data together with optical remote sensing are combined to describe and understand tidal-band and high-frequency internal wave propagation over the Oregon mid and inner shelf. Semidiurnal baroclinic velocity is dominated by the first mode at all locations, with larger velocities on the mid shelf and northern part of a large submarine bank. Mid-shelf sites have baroclinic ellipticity that is near the theoretical value for single, progressive internal tidal waves compared to more linearly polarized currents over the inner shelf. Temporal variability does not correspond to the spring-neap cycle and is overall uncorrelated between mooring locations due to variable along-shelf topography and stratification. An idealized model of two amplitude-modulated internal waves propagating from different directions reproduces some of the observed variability in inner-shelf semidiurnal ellipse parameters. Moored observations were combined with sea-surface imagery to describe the propagation of 11 bore-like internal waves across the inner shelf. The surface expression of these waves is identified by regions of increased pixel intensity during wind speeds between 2 - 5 m/s⁻¹. Optical measurements show that internal waves are refracted by bathymetry, and measured wave speed (~0.15 m/s) is higher than predicted by linear theory (< 0.1 m/s⁻¹). The number and strength of these high-frequency (15 minute period), highly nonlinear features are linked to regional-scale upwelling/downwelling as well as the phase of the mid-shelf internal tide. In general, both surface and bottom-trapped bores are observed on the inner shelf and their polarity can be predicted by the weakly nonlinear parameter of the Korteweg-de Vries wave propagation equation. These bores have different consequences for the amount of horizontal transport they accomplish and where in the water column this transport occurs. The transformation of the internal tide impacts the form of the nonlinear high-frequency oscillations observed on the inner shelf. The most efficient onshore transport of sub-thermocline water is observed during a shallow mid-shelf pycnocline with large mid-shelf semidiurnal displacement that results in only elevation waves onshore. Close

• 1434. [Article] Applied nitrogen effects on yellow mustard (Sinapis alba L.) production in the Willamette Valley

  Nitrogen management recommendations for yellow mustard (Sinapis alba L.) production in the high rainfall environment of Oregon's Willamette Valley (WV) are not available. The objectives of this investigation ...

  Citation × Citation Citation Abstract Copy Title: Applied nitrogen effects on yellow mustard (Sinapis alba L.) production in the Willamette Valley Author: DuVal, Alyssa Susan Nitrogen management recommendations for yellow mustard (Sinapis alba L.) production in the high rainfall environment of Oregon's Willamette Valley (WV) are not available. The objectives of this investigation were: (i) to determine the effect of applied nitrogen (N) on seed yield and yield components in yellow mustard, and (ii) to ascertain the effect of applied N on dry matter partitioning and oil production characteristics in yellow mustard. Field trials were conducted over a two-year period at Corvallis, Oregon, USA on 'IdaGold' yellow mustard with five N application rates: 0, 56, 112, 168, and 224 kg N ha⁻¹. Although rainfall differed greatly between the two years, the effect of applied N on seed yield and yield components were similar. Seed yield was increased by 15%-85% with applied N, primarily as a result of N-induced increases in seed weight and number. Yield ranged from 1,080 kg ha⁻¹ with 0 kg N ha⁻¹ to 2,580 kg ha⁻¹ with 224 kg N ha⁻¹. Primary racemes plant⁻¹ was positively associated with increased N; however, secondary racemes plant⁻¹ was not consistently related to N. Siliques plant-1 increased in proportion to N rate and was the result of greater numbers of siliques main stem⁻¹ and siliques primary raceme⁻¹. The relationship of applied N and siliques plant⁻¹ was manifested in seed yield, and as an example, the 224 kg N ha⁻¹ rate yielded 95% and 172% more seeds than 0 kg N ha⁻¹ in 2013 and 2014, respectively. Contributions to yield among main stem and branches varied: the main stem raceme contributed 63-66%, primary branch racemes contributed 33-36%, and secondary branch racemes accounted for the remainder. Seeds on main stems were on average 2.4% heavier than seeds on primary branch racemes within N rates. Nevertheless, N rate differentially affected seed weight as main stem seed weight was increased by 11% with 168 and by 5% with 56 kg N ha⁻¹ in 2013 and 2014, respectively. No effect of N fertilizer on primary branch seed weight was evident in 2013, but 168 and 224 kg N ha⁻¹ increased seed weight in 2014. Stand density, plant height, and above-ground biomass were determined at three developmental stages (stem elongation - BBCH 30, inflorescence emergence - BBCH 50, and harvest - BBCH 87) while leaf area index (LAI) and tissue N content were measured at BBCH 30 and BBCH 50. Applied N affected most dry matter partitioning and oil production characteristics with the exception of stand density, harvest index (HI), and seed protein concentration. Plant height, biomass, LAI, and tissue N concentration at BBCH 30 and 50 as well as crop growth rate (CGR) from BBCH 30 to 87 were related to the rate of applied N. Applied N increased plant height by 24 to 105%. Although lodging occurred in both years at the highest N rates, lodging did not negatively influence plant growth and seed yield development, nor total oil yield. As a measure of stand photosynthetic capacity, LAI was lowest across developmental stages with 0 kg N ha⁻¹ in 2013, and in the 0 and 56 kg N ha⁻¹ treatments in 2014. Increases in CGR by applied N ranged from 8 to 44% in 2013 and from 27 to 109% in 2014. Biomass N content at BBCH 30 was increased by all rates of applied N, but by BBCH 50, biomass N was only elevated over the control by rates ≥168 and ≥112 kg N ha-1 in 2013 and 2014, respectively. The rate of applied N incrementally decreased N use efficiency (NUE) with reductions ranging from 29% to 71% with only 56 kg N ha⁻¹. Seed oil concentration was generally inversely related to applied N rate; but highest oil yields were observed with 224 kg N ha⁻¹. Optimum yellow mustard plant growth, seed yield, and oil yield were found with 168-224 kg N ha⁻¹ under WV conditions. The results of this study improves our understanding of yellow mustard production in response to applied N in a high rainfall environment. Title: Applied nitrogen effects on yellow mustard (Sinapis alba L.) production in the Willamette Valley Author: DuVal, Alyssa Susan Nitrogen management recommendations for yellow mustard (Sinapis alba L.) production in the high rainfall environment of Oregon's Willamette Valley (WV) are not available. The objectives of this investigation were: (i) to determine the effect of applied nitrogen (N) on seed yield and yield components in yellow mustard, and (ii) to ascertain the effect of applied N on dry matter partitioning and oil production characteristics in yellow mustard. Field trials were conducted over a two-year period at Corvallis, Oregon, USA on 'IdaGold' yellow mustard with five N application rates: 0, 56, 112, 168, and 224 kg N ha⁻¹. Although rainfall differed greatly between the two years, the effect of applied N on seed yield and yield components were similar. Seed yield was increased by 15%-85% with applied N, primarily as a result of N-induced increases in seed weight and number. Yield ranged from 1,080 kg ha⁻¹ with 0 kg N ha⁻¹ to 2,580 kg ha⁻¹ with 224 kg N ha⁻¹. Primary racemes plant⁻¹ was positively associated with increased N; however, secondary racemes plant⁻¹ was not consistently related to N. Siliques plant-1 increased in proportion to N rate and was the result of greater numbers of siliques main stem⁻¹ and siliques primary raceme⁻¹. The relationship of applied N and siliques plant⁻¹ was manifested in seed yield, and as an example, the 224 kg N ha⁻¹ rate yielded 95% and 172% more seeds than 0 kg N ha⁻¹ in 2013 and 2014, respectively. Contributions to yield among main stem and branches varied: the main stem raceme contributed 63-66%, primary branch racemes contributed 33-36%, and secondary branch racemes accounted for the remainder. Seeds on main stems were on average 2.4% heavier than seeds on primary branch racemes within N rates. Nevertheless, N rate differentially affected seed weight as main stem seed weight was increased by 11% with 168 and by 5% with 56 kg N ha⁻¹ in 2013 and 2014, respectively. No effect of N fertilizer on primary branch seed weight was evident in 2013, but 168 and 224 kg N ha⁻¹ increased seed weight in 2014. Stand density, plant height, and above-ground biomass were determined at three developmental stages (stem elongation - BBCH 30, inflorescence emergence - BBCH 50, and harvest - BBCH 87) while leaf area index (LAI) and tissue N content were measured at BBCH 30 and BBCH 50. Applied N affected most dry matter partitioning and oil production characteristics with the exception of stand density, harvest index (HI), and seed protein concentration. Plant height, biomass, LAI, and tissue N concentration at BBCH 30 and 50 as well as crop growth rate (CGR) from BBCH 30 to 87 were related to the rate of applied N. Applied N increased plant height by 24 to 105%. Although lodging occurred in both years at the highest N rates, lodging did not negatively influence plant growth and seed yield development, nor total oil yield. As a measure of stand photosynthetic capacity, LAI was lowest across developmental stages with 0 kg N ha⁻¹ in 2013, and in the 0 and 56 kg N ha⁻¹ treatments in 2014. Increases in CGR by applied N ranged from 8 to 44% in 2013 and from 27 to 109% in 2014. Biomass N content at BBCH 30 was increased by all rates of applied N, but by BBCH 50, biomass N was only elevated over the control by rates ≥168 and ≥112 kg N ha-1 in 2013 and 2014, respectively. The rate of applied N incrementally decreased N use efficiency (NUE) with reductions ranging from 29% to 71% with only 56 kg N ha⁻¹. Seed oil concentration was generally inversely related to applied N rate; but highest oil yields were observed with 224 kg N ha⁻¹. Optimum yellow mustard plant growth, seed yield, and oil yield were found with 168-224 kg N ha⁻¹ under WV conditions. The results of this study improves our understanding of yellow mustard production in response to applied N in a high rainfall environment. Close

• 1435. [Image] The Marysville, Montana Geothermal Project (Revised)

  	The object of the Marysville Geothermal Project is to investigate a region of abnormally high geothermal heat flow near Marysville, MT, about 20 miles northwest of Helena. The research should determine ...
  	Citation × Citation Citation Abstract Copy Title: The Marysville, Montana Geothermal Project (Revised) Author: McSpadden, W.R. Year: 1974 The object of the Marysville Geothermal Project is to investigate a region of abnormally high geothermal heat flow near Marysville, MT, about 20 miles northwest of Helena. The research should determine the nature and size of the resource, how the energy might be extracted, the potential monetary value of the energy, and how similar resources elsewhere might be located. The heat source was expected to be a granitic pluton or magmatic intrusion, 10,000 to 40,000 years old, with temperatures in the range of 300 to 500°C. Originally it was thought that the pluton was at relatively shallow depths, but at present its depth and exact location are unknown Title: The Marysville, Montana Geothermal Project (Revised) Author: McSpadden, W.R. Year: 1974 The object of the Marysville Geothermal Project is to investigate a region of abnormally high geothermal heat flow near Marysville, MT, about 20 miles northwest of Helena. The research should determine the nature and size of the resource, how the energy might be extracted, the potential monetary value of the energy, and how similar resources elsewhere might be located. The heat source was expected to be a granitic pluton or magmatic intrusion, 10,000 to 40,000 years old, with temperatures in the range of 300 to 500°C. Originally it was thought that the pluton was at relatively shallow depths, but at present its depth and exact location are unknown Close

• 1436. [Article] The Development of Embedded DRAM Statistical Quality Models at Test and Use Conditions

  Today, the use of embedded Dynamic Random Access Memory (eDRAM) is increasing in our electronics that require large memories, such as gaming consoles and computer network routers. Unlike external DRAMs, ...

  Citation × Citation Citation Abstract Copy Title: The Development of Embedded DRAM Statistical Quality Models at Test and Use Conditions Author: Suzuki, Satoshi Year: 2010 Today, the use of embedded Dynamic Random Access Memory (eDRAM) is increasing in our electronics that require large memories, such as gaming consoles and computer network routers. Unlike external DRAMs, eDRAMs are embedded inside ASICs for faster read and write operations. Until recently, eDRAMs required high manufacturing cost. Present process technology developments enabled the manufacturing of eDRAM at competitive costs. Unlike SRAM, eDRAM exhibits retention time bit fails from defects and capacitor leakage current. This retention time fail causes memory bits to lose stored values before refresh. Also, a small portion of the memory bits are known to fail at a random retention time. At test conditions, more stringent than use conditions, if all possible retention time fail bits are detected and replaced, there will be no additional fail bits during use. However, detecting all the retention time fails requires long time and also rejects bits that do not fail at the use condition. This research seeks to maximize the detection of eDRAM fail bits during test by determining effective test conditions and model the failure rate of eDRAM retention time during use conditions. Title: The Development of Embedded DRAM Statistical Quality Models at Test and Use Conditions Author: Suzuki, Satoshi Year: 2010 Today, the use of embedded Dynamic Random Access Memory (eDRAM) is increasing in our electronics that require large memories, such as gaming consoles and computer network routers. Unlike external DRAMs, eDRAMs are embedded inside ASICs for faster read and write operations. Until recently, eDRAMs required high manufacturing cost. Present process technology developments enabled the manufacturing of eDRAM at competitive costs. Unlike SRAM, eDRAM exhibits retention time bit fails from defects and capacitor leakage current. This retention time fail causes memory bits to lose stored values before refresh. Also, a small portion of the memory bits are known to fail at a random retention time. At test conditions, more stringent than use conditions, if all possible retention time fail bits are detected and replaced, there will be no additional fail bits during use. However, detecting all the retention time fails requires long time and also rejects bits that do not fail at the use condition. This research seeks to maximize the detection of eDRAM fail bits during test by determining effective test conditions and model the failure rate of eDRAM retention time during use conditions. Close

• 1437. [Article] Intaglio printmaking in the secondary school

  There is a wealth of printed material on intaglio printmaking techniques and history, but there is relatively little printed material or work directed towards the inclusion of intaglio printmaking in the ...

  Citation × Citation Citation Abstract Copy Title: Intaglio printmaking in the secondary school Author: Wylder, James Lester Year: 1968 There is a wealth of printed material on intaglio printmaking techniques and history, but there is relatively little printed material or work directed towards the inclusion of intaglio printmaking in the secondary school art curriculum. It is my basic assertion in this thesis that intaglio printmaking can be taught with success at the secondary level. The thesis consists of three chapters. The first chapter is concerned with the purpose, value, and application of intaglio printmaking in a secondary school art program. The second chapter identifies the materials, the cost of materials, and the sources of supply. Chapter three deals with the organization of materials in the classroom. Photographs of intaglio prints comprise the visual aspect of the thesis and supplement the text in some instances. I have supplemented the photographs of my own work with original prints by high school students, which should give some idea of the student's competence. Photographs of some of the paintings and drawings that I completed during the Master of Science inTeaching program are in the appendix. This will provide a record or my work for the art department and is intended as a supplement to the thesis. Title: Intaglio printmaking in the secondary school Author: Wylder, James Lester Year: 1968 There is a wealth of printed material on intaglio printmaking techniques and history, but there is relatively little printed material or work directed towards the inclusion of intaglio printmaking in the secondary school art curriculum. It is my basic assertion in this thesis that intaglio printmaking can be taught with success at the secondary level. The thesis consists of three chapters. The first chapter is concerned with the purpose, value, and application of intaglio printmaking in a secondary school art program. The second chapter identifies the materials, the cost of materials, and the sources of supply. Chapter three deals with the organization of materials in the classroom. Photographs of intaglio prints comprise the visual aspect of the thesis and supplement the text in some instances. I have supplemented the photographs of my own work with original prints by high school students, which should give some idea of the student's competence. Photographs of some of the paintings and drawings that I completed during the Master of Science inTeaching program are in the appendix. This will provide a record or my work for the art department and is intended as a supplement to the thesis. Close

• 1438. [Article] Self-Management and Social Skills Training for Persons With Developmental Disabilities: Tools for the Rehabilitation Counselor to Facilitate Success in Community Settings: A Literature Review

  People with developmental disabilities often display deficiencies in self-management and social skills in community based settings. Difficulties with self-management and social skills tend to pose particular ...

  Citation × Citation Citation Abstract Copy Title: Self-Management and Social Skills Training for Persons With Developmental Disabilities: Tools for the Rehabilitation Counselor to Facilitate Success in Community Settings: A Literature Review Author: Anctil, Tina M., Degeneffe, Charles Edmund Year: 2003 People with developmental disabilities often display deficiencies in self-management and social skills in community based settings. Difficulties with self-management and social skills tend to pose particular difficulties for performing valued adult roles. Tools from behavior therapy have the potential to assist rehabilitation counselors in their work with consumers with developmental disabilities to overcome the negative impacts of functional limitations on expressing behaviors needed for success in community-based settings. This article presents a review of the behavior therapy literature regarding self-management and social skills training techniques rehabilitation counselors can use in their work with consumers with developmental disabilities in areas including high school transition and supported employment. Title: Self-Management and Social Skills Training for Persons With Developmental Disabilities: Tools for the Rehabilitation Counselor to Facilitate Success in Community Settings: A Literature Review Author: Anctil, Tina M., Degeneffe, Charles Edmund Year: 2003 People with developmental disabilities often display deficiencies in self-management and social skills in community based settings. Difficulties with self-management and social skills tend to pose particular difficulties for performing valued adult roles. Tools from behavior therapy have the potential to assist rehabilitation counselors in their work with consumers with developmental disabilities to overcome the negative impacts of functional limitations on expressing behaviors needed for success in community-based settings. This article presents a review of the behavior therapy literature regarding self-management and social skills training techniques rehabilitation counselors can use in their work with consumers with developmental disabilities in areas including high school transition and supported employment. Close

• 1439. [Article] Analytical Modeling of Cake Filtration

  The specific resistance model of cake filtration is based on the assumption that the average cake resistance is constant over time. This implies also that the spatially average values of porosity and pressure ...

  Citation × Citation Citation Abstract Copy Title: Analytical Modeling of Cake Filtration Author: Wells, Scott A. Year: 1999 The specific resistance model of cake filtration is based on the assumption that the average cake resistance is constant over time. This implies also that the spatially average values of porosity and pressure differential are also constant over time since specific resistance is a function of both parameters. An analytical cake filtration model based on Tiller (1975) was derived using constitutive properties of kaolin suspensions in distilled water. Constitutive properties were determined by experiments performed using high-energy X-rays and porewater pressure probes to determine the spatial and temporal distributions of porosity and porewater pressure. Using these constitutive properties, predictions were made of porewater pressure and porosity distributions using the analytical model. Porosity data were used to compare to the analytical model predictions assuming that porosity and pressure were functions only of fractional cake position. Title: Analytical Modeling of Cake Filtration Author: Wells, Scott A. Year: 1999 The specific resistance model of cake filtration is based on the assumption that the average cake resistance is constant over time. This implies also that the spatially average values of porosity and pressure differential are also constant over time since specific resistance is a function of both parameters. An analytical cake filtration model based on Tiller (1975) was derived using constitutive properties of kaolin suspensions in distilled water. Constitutive properties were determined by experiments performed using high-energy X-rays and porewater pressure probes to determine the spatial and temporal distributions of porosity and porewater pressure. Using these constitutive properties, predictions were made of porewater pressure and porosity distributions using the analytical model. Porosity data were used to compare to the analytical model predictions assuming that porosity and pressure were functions only of fractional cake position. Close

• 1440. [Article] Analysis of the Impacts of Transit Signal Priority on Bus Bunching and Performance

  Efficient and reliable public transit systems provide opportunities to reduce congestion, emissions in urban areas and provide access and mobility to residents. Headway, or the time difference between ...

  Citation × Citation Citation Abstract Copy Title: Analysis of the Impacts of Transit Signal Priority on Bus Bunching and Performance Author: Albright, Eric, Figliozzi, Miguel Andres Year: 2012 Efficient and reliable public transit systems provide opportunities to reduce congestion, emissions in urban areas and provide access and mobility to residents. Headway, or the time difference between departing or arriving vehicles, is a useful measure to gauge bus transit performance; because short headways can lead to bus bunching incidents that quickly degrade transit level of service. While Transit Signal Priority (TSP) has been shown to decrease travel time and delay experienced by buses, little work has shown how TSP may affect bus bunching. This research attempts to understand the characteristics of bus trips, especially TSP, that prevent or promote short headways, or bus bunching. A study of two transit routes in SE Portland is presented. High values of negative serial correlation were observed among consecutive headway observations. A regression model is used to analyze factors (boardings, alightings, stops, lift usage, Transit Signal Priority and direction of travel) that may influence bus headways. Priority requests are shown to have a significant effect on headways. Title: Analysis of the Impacts of Transit Signal Priority on Bus Bunching and Performance Author: Albright, Eric, Figliozzi, Miguel Andres Year: 2012 Efficient and reliable public transit systems provide opportunities to reduce congestion, emissions in urban areas and provide access and mobility to residents. Headway, or the time difference between departing or arriving vehicles, is a useful measure to gauge bus transit performance; because short headways can lead to bus bunching incidents that quickly degrade transit level of service. While Transit Signal Priority (TSP) has been shown to decrease travel time and delay experienced by buses, little work has shown how TSP may affect bus bunching. This research attempts to understand the characteristics of bus trips, especially TSP, that prevent or promote short headways, or bus bunching. A study of two transit routes in SE Portland is presented. High values of negative serial correlation were observed among consecutive headway observations. A regression model is used to analyze factors (boardings, alightings, stops, lift usage, Transit Signal Priority and direction of travel) that may influence bus headways. Priority requests are shown to have a significant effect on headways. Close