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• 671. [Article] Investigation of a new resin as an exterior adhesive to bond high moisture content veneers

  A new carbohydrate-phenol based resorcinol resin (CPR resin) was synthesized by end capping a known carbohydrate-phenol based resole with resorcinol under basic reaction conditions. Synthetic parameters, ...

  Citation × Citation Citation Abstract Copy Title: Investigation of a new resin as an exterior adhesive to bond high moisture content veneers Author: Clark, Randy Jon A new carbohydrate-phenol based resorcinol resin (CPR resin) was synthesized by end capping a known carbohydrate-phenol based resole with resorcinol under basic reaction conditions. Synthetic parameters, such as duration of cook, pH, and the amount of resorcinol and formaldehyde were varied to produce resins with molecular weights (Mw) ranging from 1500 to 8000. These resins were tested for suitability as fast curing thermosetting adhesives to bond high moisture content veneers and as a cold-setting adhesive for producing glu-lam. The resin formulation which produced the best wood failure results was made with a glucose: urea: phenol: formaldehyde: resorcinol mole ratio of 1:0.75:1:2.0:1.3. When this resin (Mw 4776) was combined with liquid formaldehyde, paraformaldehyde, and walnut shell flour it exhibited a viscosity of 12,000 centipoise and a gel time of 35 minutes at room temperature. This adhesive was able to bond 18% moisture content veneers into 10" by 10" 3-ply plywood panels and lumber laminates into glu-lam panels. Plywood panels were produced with a glue spread ranging from 45 to 70 #/MDGL with pressing conditions of 175 psi and 285°F for 8 minutes. Microscopic observations of plywood gluelines showed severe wood fiber compression in the high moisture content veneers. Shear tests of specimens gave an average wood failure value of 85% after vacuum-pressure conditioning in water and a 75% average after boiling. The low value for the boil test seems to be related to the high moisture content of the veneers because cured adhesive samples were found to be insoluble in water. Wood failure values greater than 90% were obtained from shear specimens of the glu-lam panels for three conditioning methods (dry, vacuum-pressure, and boil). Carbon-13 NMR spectra of the CPR resins synthesized in this study showed that the glucosyl moiety is still intact in the polymer, perhaps as a glucosylurea derivative. This result is in contrast to some previous work which suggested furan polymers would be formed under the conditions used here. These CPR resins show excellent potential for use in gluing high moisture content veneers and in glu-lam applications. Title: Investigation of a new resin as an exterior adhesive to bond high moisture content veneers Author: Clark, Randy Jon A new carbohydrate-phenol based resorcinol resin (CPR resin) was synthesized by end capping a known carbohydrate-phenol based resole with resorcinol under basic reaction conditions. Synthetic parameters, such as duration of cook, pH, and the amount of resorcinol and formaldehyde were varied to produce resins with molecular weights (Mw) ranging from 1500 to 8000. These resins were tested for suitability as fast curing thermosetting adhesives to bond high moisture content veneers and as a cold-setting adhesive for producing glu-lam. The resin formulation which produced the best wood failure results was made with a glucose: urea: phenol: formaldehyde: resorcinol mole ratio of 1:0.75:1:2.0:1.3. When this resin (Mw 4776) was combined with liquid formaldehyde, paraformaldehyde, and walnut shell flour it exhibited a viscosity of 12,000 centipoise and a gel time of 35 minutes at room temperature. This adhesive was able to bond 18% moisture content veneers into 10" by 10" 3-ply plywood panels and lumber laminates into glu-lam panels. Plywood panels were produced with a glue spread ranging from 45 to 70 #/MDGL with pressing conditions of 175 psi and 285°F for 8 minutes. Microscopic observations of plywood gluelines showed severe wood fiber compression in the high moisture content veneers. Shear tests of specimens gave an average wood failure value of 85% after vacuum-pressure conditioning in water and a 75% average after boiling. The low value for the boil test seems to be related to the high moisture content of the veneers because cured adhesive samples were found to be insoluble in water. Wood failure values greater than 90% were obtained from shear specimens of the glu-lam panels for three conditioning methods (dry, vacuum-pressure, and boil). Carbon-13 NMR spectra of the CPR resins synthesized in this study showed that the glucosyl moiety is still intact in the polymer, perhaps as a glucosylurea derivative. This result is in contrast to some previous work which suggested furan polymers would be formed under the conditions used here. These CPR resins show excellent potential for use in gluing high moisture content veneers and in glu-lam applications. Close

• 672. [Article] Growth and characterization of zinc ferrite thin films for high frequency applications

  Ferrites have been used for various high frequency applications as bulk materials. These applications, however, are limited to large dimension devices. In this thesis, thin film ferrites were deposited ...

  Citation × Citation Citation Abstract Copy Title: Growth and characterization of zinc ferrite thin films for high frequency applications Author: Hu, Jiqing Ferrites have been used for various high frequency applications as bulk materials. These applications, however, are limited to large dimension devices. In this thesis, thin film ferrites were deposited from a low temperature solution-based deposition process that is suitable for micro-scale high frequency applications. The low temperature nature of this deposition technique makes it an excellent back end process. In this work, a high rate deposition process for zinc ferrite thin films was established. A deposition rate of 0.2 μm/min was determined by the surface profiler. The deposited films have a plate-like morphology with fibrous texture. Zinc was uniformly incorporated into the ferrite film confirmed by the local chemical analysis by Energy Dispersive X-ray spectroscopy. The deposited films are polycrystalline with a typical cubic ferrite structure. The overall composition of the films was determined by Auger electron spectroscopy as Zn[subscript x]Fe[subscript y]O[subscript 4], x ranges from 0.25 to 0.55, and y ranges from 2.2 to 2.7. A model consisting of resistors, capacitors and inductors was constructed and used for the analysis of impedance spectroscopy. The dielectric properties of zinc ferrite thin films were obtained by fitting the data to the model. The results show that the dielectric constants are around 15 regardless of Zn/Fe ratio. This value is consistent with most of the reported values for bulk ferrite materials. The resistivity changes from 0.6 x 10[superscript 6] ohm.meter to 1.3 x 10[superscript 6] ohm.meter when Zn/Fe ratio varies from 0.06 to 0.14. A grounded coplanar waveguide structure was developed for microwave characterization of the thin film material to obtain the complex relative permittivity and the complex relative permeability. The method is based on conformal mapping and determination of filling factors for the coplanar waveguide configuration and is applicable to a wide range of dielectric as well as magnetic materials. The proposed approach was validated by determining the scattering parameters of a number of test structures using the 3D full-wave electromagnetic simulation. In all examples, the extracted parameters from the proposed technique resulted in values that are within 2% error. Title: Growth and characterization of zinc ferrite thin films for high frequency applications Author: Hu, Jiqing Ferrites have been used for various high frequency applications as bulk materials. These applications, however, are limited to large dimension devices. In this thesis, thin film ferrites were deposited from a low temperature solution-based deposition process that is suitable for micro-scale high frequency applications. The low temperature nature of this deposition technique makes it an excellent back end process. In this work, a high rate deposition process for zinc ferrite thin films was established. A deposition rate of 0.2 μm/min was determined by the surface profiler. The deposited films have a plate-like morphology with fibrous texture. Zinc was uniformly incorporated into the ferrite film confirmed by the local chemical analysis by Energy Dispersive X-ray spectroscopy. The deposited films are polycrystalline with a typical cubic ferrite structure. The overall composition of the films was determined by Auger electron spectroscopy as Zn[subscript x]Fe[subscript y]O[subscript 4], x ranges from 0.25 to 0.55, and y ranges from 2.2 to 2.7. A model consisting of resistors, capacitors and inductors was constructed and used for the analysis of impedance spectroscopy. The dielectric properties of zinc ferrite thin films were obtained by fitting the data to the model. The results show that the dielectric constants are around 15 regardless of Zn/Fe ratio. This value is consistent with most of the reported values for bulk ferrite materials. The resistivity changes from 0.6 x 10[superscript 6] ohm.meter to 1.3 x 10[superscript 6] ohm.meter when Zn/Fe ratio varies from 0.06 to 0.14. A grounded coplanar waveguide structure was developed for microwave characterization of the thin film material to obtain the complex relative permittivity and the complex relative permeability. The method is based on conformal mapping and determination of filling factors for the coplanar waveguide configuration and is applicable to a wide range of dielectric as well as magnetic materials. The proposed approach was validated by determining the scattering parameters of a number of test structures using the 3D full-wave electromagnetic simulation. In all examples, the extracted parameters from the proposed technique resulted in values that are within 2% error. Close

• 673. [Article] The effects of tillage systems and seeding dates on grain yields of wheat (Triticum aestivum Vill., Host) on the Anatolian Plateau of Turkey

  Wheat (Triticum aestivum) is the major food crop produced on the Anatolian Plateau of Turkey where due to limited rainfall the farmers follow the traditional system of fallow farming. They are presently ...

  Citation × Citation Citation Abstract Copy Title: The effects of tillage systems and seeding dates on grain yields of wheat (Triticum aestivum Vill., Host) on the Anatolian Plateau of Turkey Author: Zinn, Thomas G. Wheat (Triticum aestivum) is the major food crop produced on the Anatolian Plateau of Turkey where due to limited rainfall the farmers follow the traditional system of fallow farming. They are presently producing an average of 1.15 tons of grain per hectare during the crop year. This rate of production does not meet the needs of the country and during the last 15-20 years Turkey has frequently had to import wheat. The present fallow system permits extensive livestock grazing during the late fall and winter months in the noncrop year. Spring tillage practices are delayed to permit weed growth for additional foraging by livestock during the early and late spring period. This delayed spring tillage, using wooden or steel plows, leaves the soil loose and subject to rapid drying. Little plant residue is left on the surface to protect the soil and maintain water infiltration rates. The farmer also must cultivate several times before planting in order to prepare a satisfactory seedbed. Under these conditions Turkish farmers have learned that seed planted early in the fall in dry, warm soil may be germinated by light rain, subsequently dry out and then die. Thus, they have over time adopted the practice of delaying planting until late fall when temperatures are cooler and frequent rains more certain. Under these conditions the crop is largely dependent upon late spring and early summer rains for satisfactory grain production. Climate in dryland regions of Oregon and Washington are similar to those in the Anatolian Plateau. Previous research conducted on the Anatolian Plateau indicated that modified technology from Oregon and Washington could be adopted to Turkish conditions resulting in substantial increases in grain yield. The objective of this study was to compare three fallow-tillage systems for moisture conservation and early vs. late seeding dates on subsequent grain yield of wheat. The tillage treatments were (1) a fall chisel operation followed by a spring chisel tillage, (2) chiselling twice in the spring in perpendicular directions, and (3) moldboard plowing in the spring. All three systems received subsequent tillages with a sweep-harrow combination as required to maintain a weedfree fallow and uniform seedbed. The amount of moisture conserved was not affected by the three tillage systems employed and grain yield was not different due to tillage method. All of the systems conserved sufficient water to allow early seeding into residual moisture with a deep furrow drill. A 94 per cent stand emerged within 15 days. At a later sowing date wheat was seeded into dry soil using a double disc drill. Emergence was delayed due to late rains. After 56 days an 89 per cent stand had emerged. In this experiment a 36 per cent grain yield increase resulted from early seeding; 3.79 tons per hectare compared to 2.79 tons per hectare from the late seeded plots, a highly significant difference. The 3.79 tons per hectare is 2.64 tons per hectare more than the average yield from local farms, where a traditional fallow system is followed. The major components contributing to the yield increases from early seeding were (1) more plants and heads per unit area, (2) more kernels per head and to a lesser degree (3) kernel weight. This study suggests that if Turkish farmers adopt improved summer fallow systems, wheat yields can be increased significantly; thus, reducing or perhaps eliminating the need for importing wheat. However, the loss of grazing land under a clean fallow system for livestock will need to be evaluated in terms of the total economic and social conditions to determine if the increased wheat yields warrant the change in farming practices. It is anticipated that the loss of forage during the fallow period would be offset by the increase of stubble and cereal aftermath as a result of grain yield increase during the cropping sequence. Title: The effects of tillage systems and seeding dates on grain yields of wheat (Triticum aestivum Vill., Host) on the Anatolian Plateau of Turkey Author: Zinn, Thomas G. Wheat (Triticum aestivum) is the major food crop produced on the Anatolian Plateau of Turkey where due to limited rainfall the farmers follow the traditional system of fallow farming. They are presently producing an average of 1.15 tons of grain per hectare during the crop year. This rate of production does not meet the needs of the country and during the last 15-20 years Turkey has frequently had to import wheat. The present fallow system permits extensive livestock grazing during the late fall and winter months in the noncrop year. Spring tillage practices are delayed to permit weed growth for additional foraging by livestock during the early and late spring period. This delayed spring tillage, using wooden or steel plows, leaves the soil loose and subject to rapid drying. Little plant residue is left on the surface to protect the soil and maintain water infiltration rates. The farmer also must cultivate several times before planting in order to prepare a satisfactory seedbed. Under these conditions Turkish farmers have learned that seed planted early in the fall in dry, warm soil may be germinated by light rain, subsequently dry out and then die. Thus, they have over time adopted the practice of delaying planting until late fall when temperatures are cooler and frequent rains more certain. Under these conditions the crop is largely dependent upon late spring and early summer rains for satisfactory grain production. Climate in dryland regions of Oregon and Washington are similar to those in the Anatolian Plateau. Previous research conducted on the Anatolian Plateau indicated that modified technology from Oregon and Washington could be adopted to Turkish conditions resulting in substantial increases in grain yield. The objective of this study was to compare three fallow-tillage systems for moisture conservation and early vs. late seeding dates on subsequent grain yield of wheat. The tillage treatments were (1) a fall chisel operation followed by a spring chisel tillage, (2) chiselling twice in the spring in perpendicular directions, and (3) moldboard plowing in the spring. All three systems received subsequent tillages with a sweep-harrow combination as required to maintain a weedfree fallow and uniform seedbed. The amount of moisture conserved was not affected by the three tillage systems employed and grain yield was not different due to tillage method. All of the systems conserved sufficient water to allow early seeding into residual moisture with a deep furrow drill. A 94 per cent stand emerged within 15 days. At a later sowing date wheat was seeded into dry soil using a double disc drill. Emergence was delayed due to late rains. After 56 days an 89 per cent stand had emerged. In this experiment a 36 per cent grain yield increase resulted from early seeding; 3.79 tons per hectare compared to 2.79 tons per hectare from the late seeded plots, a highly significant difference. The 3.79 tons per hectare is 2.64 tons per hectare more than the average yield from local farms, where a traditional fallow system is followed. The major components contributing to the yield increases from early seeding were (1) more plants and heads per unit area, (2) more kernels per head and to a lesser degree (3) kernel weight. This study suggests that if Turkish farmers adopt improved summer fallow systems, wheat yields can be increased significantly; thus, reducing or perhaps eliminating the need for importing wheat. However, the loss of grazing land under a clean fallow system for livestock will need to be evaluated in terms of the total economic and social conditions to determine if the increased wheat yields warrant the change in farming practices. It is anticipated that the loss of forage during the fallow period would be offset by the increase of stubble and cereal aftermath as a result of grain yield increase during the cropping sequence. Close

• 674. [Article] Nutrient Profile and Nursery Feeding Damage of Halyomorpha halys (Hempitera: Pentatomidae)

  Halyomorpha halys Stål, brown marmorated stink bug or BMSB, is now present in 43 US states. A native of eastern Asia, this pest can feed on ~200 different plant species damaging bark, leaves, buds, stems, ...

  Citation × Citation Citation Abstract Copy Title: Nutrient Profile and Nursery Feeding Damage of Halyomorpha halys (Hempitera: Pentatomidae) Author: Skillman, Victoria P. Halyomorpha halys Stål, brown marmorated stink bug or BMSB, is now present in 43 US states. A native of eastern Asia, this pest can feed on ~200 different plant species damaging bark, leaves, buds, stems, and fruits. Many of these plant species include wild plants, ornamentals, and agricultural crops. BMSB has become a major pest for growers in different cropping systems from orchard to row crops. They are also a major nuisance for homeowners because they overwinter in high numbers in human structures, where they annoy occupants and can cause other problems. Currently, much research has focused on the control and biology of BMSB. This thesis focuses on areas of BMSB biology where there are substantial knowledge gaps: the nutritional ecology of wild BMSB, nutrient content of BMSB eggs, and how BMSB feeding affects nursery crop growth. Understanding of the nutritional profile of wild BMSB over the season can help us understand how BMSB behavior is driven by nutritional needs and can indicate periods when pest is nutrient-limited and potentially more susceptible to management. In Chapter 2, lipid, glycogen and sugar levels of wild adult BMSB populations were measured in the Willamette Valley of Oregon as they emerged from overwintering boxes from March through June and throughout the summer season from May to September. Emerging adults had lower nutrient levels than overwintering adults that remained in the shelter suggesting that nutrient limitation may drive adults to leave overwintering sites. Also, nutrient levels of emerging adults steadily declined over the months that they emerged. In the summer, nutrient levels of adults collected from holly host plants fluctuated, and a dip in nutrient levels was observed as the new generation of adults became abundant. In Chapter 3, the nutrient content of BMSB eggs were measured to describe what resources are provided to the progeny and to the natural enemies that feed on or develop within eggs. Also, various fresh and frozen egg masses are used for biological control studies, and nutrient comparisons were made between various egg masses to assess quality. BMSB eggs followed adult nutrient trends by having higher lipid levels compared to sugar and glycogen. Eggs did not vary in nutrient levels over the lifespan of the female suggesting that when supplied a consistent diet, females allocate a consistent amount of nutrient to their eggs as they age. Wild and colony egg clusters varied in lipid and sugar levels. The color change and age of the egg clusters did not influence the nutrient levels. The deployment length caused eggs to decrease in sugar and glycogen levels, however, temperature and deployment*temperature combinations did not. Eggs that were frozen at -80°C for 1-2 years were associated with declining lipid levels and increasing sugar levels. While BMSB has been reported to damage nursery crops, and especially fruit, their impact on plant growth has not been quantified. Experiments represented in Chapter 4 evaluated BMSB feeding damage to nursery plants by caging adults on established stock block trees in the field and young potted seedlings in the greenhouse. The impact appeared limited; the established trees and young seedlings mostly grew at similar rates to control plants. In addition to these three topics, four additional nutrient profiles studies and two studies on biological control are included in the Appendices. Baseline information on the nutrient levels of the general adult population of BMSB in Oregon (A.1), BMSB nymphs (A.3), and native stink bugs of Oregon (A.4) are provided. Nutrient comparisons in May-June revealed that BMSB collected from the host plant of holly had substantially higher nutrient reserves than BMSB just exiting overwintering (A.2). Methyl salicylate lures were tested in a nursery and found to have no significant effect on egg predation or parasitism (A.5). A commercially available entomopathogenic fungus was sprayed directly on BMSB nymphs; it induced 26% greater mortality than the controls over a 12-day period. Title: Nutrient Profile and Nursery Feeding Damage of Halyomorpha halys (Hempitera: Pentatomidae) Author: Skillman, Victoria P. Halyomorpha halys Stål, brown marmorated stink bug or BMSB, is now present in 43 US states. A native of eastern Asia, this pest can feed on ~200 different plant species damaging bark, leaves, buds, stems, and fruits. Many of these plant species include wild plants, ornamentals, and agricultural crops. BMSB has become a major pest for growers in different cropping systems from orchard to row crops. They are also a major nuisance for homeowners because they overwinter in high numbers in human structures, where they annoy occupants and can cause other problems. Currently, much research has focused on the control and biology of BMSB. This thesis focuses on areas of BMSB biology where there are substantial knowledge gaps: the nutritional ecology of wild BMSB, nutrient content of BMSB eggs, and how BMSB feeding affects nursery crop growth. Understanding of the nutritional profile of wild BMSB over the season can help us understand how BMSB behavior is driven by nutritional needs and can indicate periods when pest is nutrient-limited and potentially more susceptible to management. In Chapter 2, lipid, glycogen and sugar levels of wild adult BMSB populations were measured in the Willamette Valley of Oregon as they emerged from overwintering boxes from March through June and throughout the summer season from May to September. Emerging adults had lower nutrient levels than overwintering adults that remained in the shelter suggesting that nutrient limitation may drive adults to leave overwintering sites. Also, nutrient levels of emerging adults steadily declined over the months that they emerged. In the summer, nutrient levels of adults collected from holly host plants fluctuated, and a dip in nutrient levels was observed as the new generation of adults became abundant. In Chapter 3, the nutrient content of BMSB eggs were measured to describe what resources are provided to the progeny and to the natural enemies that feed on or develop within eggs. Also, various fresh and frozen egg masses are used for biological control studies, and nutrient comparisons were made between various egg masses to assess quality. BMSB eggs followed adult nutrient trends by having higher lipid levels compared to sugar and glycogen. Eggs did not vary in nutrient levels over the lifespan of the female suggesting that when supplied a consistent diet, females allocate a consistent amount of nutrient to their eggs as they age. Wild and colony egg clusters varied in lipid and sugar levels. The color change and age of the egg clusters did not influence the nutrient levels. The deployment length caused eggs to decrease in sugar and glycogen levels, however, temperature and deployment*temperature combinations did not. Eggs that were frozen at -80°C for 1-2 years were associated with declining lipid levels and increasing sugar levels. While BMSB has been reported to damage nursery crops, and especially fruit, their impact on plant growth has not been quantified. Experiments represented in Chapter 4 evaluated BMSB feeding damage to nursery plants by caging adults on established stock block trees in the field and young potted seedlings in the greenhouse. The impact appeared limited; the established trees and young seedlings mostly grew at similar rates to control plants. In addition to these three topics, four additional nutrient profiles studies and two studies on biological control are included in the Appendices. Baseline information on the nutrient levels of the general adult population of BMSB in Oregon (A.1), BMSB nymphs (A.3), and native stink bugs of Oregon (A.4) are provided. Nutrient comparisons in May-June revealed that BMSB collected from the host plant of holly had substantially higher nutrient reserves than BMSB just exiting overwintering (A.2). Methyl salicylate lures were tested in a nursery and found to have no significant effect on egg predation or parasitism (A.5). A commercially available entomopathogenic fungus was sprayed directly on BMSB nymphs; it induced 26% greater mortality than the controls over a 12-day period. Close

• 675. [Article] Cultural Behavior in Post-Urbanized Brazil: The Cordial Man and Intrafamilial Conflict

  Cultures, subcultures, and individuals occupy different positions in the low-context/individualistic and the high-context/collectivistic spectrum, and they shift due to factors such as urbanization, economic ...

  Citation × Citation Citation Abstract Copy Title: Cultural Behavior in Post-Urbanized Brazil: The Cordial Man and Intrafamilial Conflict Author: La Rosa, Thais Year: 2013 Cultures, subcultures, and individuals occupy different positions in the low-context/individualistic and the high-context/collectivistic spectrum, and they shift due to factors such as urbanization, economic development and cultural globalization. In this study, I examine Sérgio Buarque de Holanda's theory of the cordial man and how it illustrates qualities of the high-context Brazilian culture. Within the framework of grounded theory, these qualities are evaluated from the perspective of intergenerational dyads--fathers and sons--that have been exposed to an urbanized and globalized environment in order to determine whether and how a shift from high-context to low-context is occurring. The participants were interviewed to explore perception of self, upbringing, decision-making process within the family, father and son relationships, intrafamilial communication, ways to influence and be influenced, history of conflict, and urbanization and globalization. Their responses revealed the extent to which their values were individualistic or group-oriented and if the cordial man behavior was also present in the intimacy of their homes. In sum, I reach three conclusions: technological and cultural globalization propagates low-context values and behaviors; sons are in a transitional state, in which individual goals are relevant enough to challenge parental expectations, but still cause guilt when pursued; and, the cordial man still exists in the urban and globalized world. Implications for families, family therapists, counselors and mediators are discussed. Title: Cultural Behavior in Post-Urbanized Brazil: The Cordial Man and Intrafamilial Conflict Author: La Rosa, Thais Year: 2013 Cultures, subcultures, and individuals occupy different positions in the low-context/individualistic and the high-context/collectivistic spectrum, and they shift due to factors such as urbanization, economic development and cultural globalization. In this study, I examine Sérgio Buarque de Holanda's theory of the cordial man and how it illustrates qualities of the high-context Brazilian culture. Within the framework of grounded theory, these qualities are evaluated from the perspective of intergenerational dyads--fathers and sons--that have been exposed to an urbanized and globalized environment in order to determine whether and how a shift from high-context to low-context is occurring. The participants were interviewed to explore perception of self, upbringing, decision-making process within the family, father and son relationships, intrafamilial communication, ways to influence and be influenced, history of conflict, and urbanization and globalization. Their responses revealed the extent to which their values were individualistic or group-oriented and if the cordial man behavior was also present in the intimacy of their homes. In sum, I reach three conclusions: technological and cultural globalization propagates low-context values and behaviors; sons are in a transitional state, in which individual goals are relevant enough to challenge parental expectations, but still cause guilt when pursued; and, the cordial man still exists in the urban and globalized world. Implications for families, family therapists, counselors and mediators are discussed. Close

• 676. [Article] An Analysis of the Involvement of Ten High Schools in Scholastic Aptitude Testing Student Preparation

  The Scholastic Aptitude Test (SAT) is taken each year by two fifths of the high school graduates (Cameron, 1989). The perception that high SAT scores will either open the door of selective colleges and ...

  Citation × Citation Citation Abstract Copy Title: An Analysis of the Involvement of Ten High Schools in Scholastic Aptitude Testing Student Preparation Author: Drakulich, Elaine Year: 1993 The Scholastic Aptitude Test (SAT) is taken each year by two fifths of the high school graduates (Cameron, 1989). The perception that high SAT scores will either open the door of selective colleges and generate scholarships or that low SAT scores will close off opportunities for the rest of one’ life, makes virtually every student who invests the three hours of time required to take the test extremely anxious about doing as well as possible (Whitla, 1988). Significant relationships between identified preparation techniques and the perceived effectiveness of those techniques by students and staff can be very useful information for educators when counseling and/or assisting students who want to improve their performance on the SAT. This study describes perceptual opinions from students, teachers, counselors, and administrators from 10 Portland, Oregon metropolitan area schools about the effectiveness of three SAT preparation techniques. The following research questions were examined: 1. What is the perceived effectiveness of three SAT preparation techniques: SAT computer programs, SAT preparation classes, and specific SAT information taught in general classes? 2. Are students who regard the SAT as important more likely to know about, use, and perceive effective the three preparation techniques than students who do not? 3. Are students who regard the SAT as important more likely to perceive their teachers or administrators as valuing the SAT than students who do not? 4. Are students who perceive that their teachers or administrators regard the SAT as important more likely to perceive the preparation techniques effective than students who do not? The results of this study indicated some specific groups of students and teachers did perceive one preparation technique to be effective. Their perceptions validated belief in specific SAT information taught in general classes as an effective preparation technique. It also revealed that there was lack of awareness, use, and perceived effectiveness of both SAT computer programs and SAT preparation classes. Lastly, the study showed that both students and teachers who perceived the SAT to be important, agreed that their administrators valued the SAT. Title: An Analysis of the Involvement of Ten High Schools in Scholastic Aptitude Testing Student Preparation Author: Drakulich, Elaine Year: 1993 The Scholastic Aptitude Test (SAT) is taken each year by two fifths of the high school graduates (Cameron, 1989). The perception that high SAT scores will either open the door of selective colleges and generate scholarships or that low SAT scores will close off opportunities for the rest of one’ life, makes virtually every student who invests the three hours of time required to take the test extremely anxious about doing as well as possible (Whitla, 1988). Significant relationships between identified preparation techniques and the perceived effectiveness of those techniques by students and staff can be very useful information for educators when counseling and/or assisting students who want to improve their performance on the SAT. This study describes perceptual opinions from students, teachers, counselors, and administrators from 10 Portland, Oregon metropolitan area schools about the effectiveness of three SAT preparation techniques. The following research questions were examined: 1. What is the perceived effectiveness of three SAT preparation techniques: SAT computer programs, SAT preparation classes, and specific SAT information taught in general classes? 2. Are students who regard the SAT as important more likely to know about, use, and perceive effective the three preparation techniques than students who do not? 3. Are students who regard the SAT as important more likely to perceive their teachers or administrators as valuing the SAT than students who do not? 4. Are students who perceive that their teachers or administrators regard the SAT as important more likely to perceive the preparation techniques effective than students who do not? The results of this study indicated some specific groups of students and teachers did perceive one preparation technique to be effective. Their perceptions validated belief in specific SAT information taught in general classes as an effective preparation technique. It also revealed that there was lack of awareness, use, and perceived effectiveness of both SAT computer programs and SAT preparation classes. Lastly, the study showed that both students and teachers who perceived the SAT to be important, agreed that their administrators valued the SAT. Close

• 677. [Article] Turkish Student Teachers' Early Experiences in Schools: Critical Incidents, Reflection, and a New Teacher Education Program

  In Turkey there is an old saying about how parents feel about the role of schools: "The bones are mine, but the flesh is yours." Turkish parents want schools to not only educate but to mold and shape the ...

  Citation × Citation Citation Abstract Copy Title: Turkish Student Teachers' Early Experiences in Schools: Critical Incidents, Reflection, and a New Teacher Education Program Author: Stevens, Dannelle D., Sarigul, Serap, Deger, Hulya Year: 2002 In Turkey there is an old saying about how parents feel about the role of schools: "The bones are mine, but the flesh is yours." Turkish parents want schools to not only educate but to mold and shape the values of their children in ways that the educators think appropriate. Ever since Turkey became a republic in 1923 under the leadership of Mustafa Kemal Ataturk, education has been highly valued. In 1924, Ataturk invited John Dewey to assess and report on the situation in Turkish schools. In Turkish villages, anyone with an education was highly respected. Old people stood up out of respect when a student returned to the village with a high school diploma or even better, a college degree. The saying echoes this blind trust in the ultimate authority and responsibility of schools to educate children. The primary purpose of this article is to report how Turkish student teachers identify and reflect on the "critical incidents" of schooling that they bring as they enter a new teacher education program. "Critical incidents" are descriptions of incidents in one's past that are viewed as significant in one's learning and development. The secondary purpose of this article is to analyze these incidents to inform the first author's teaching and field supervision. In this way, this study is an action research project designed to be a systematic study of her own practice of assessing the nature of students' background knowledge of teaching. Title: Turkish Student Teachers' Early Experiences in Schools: Critical Incidents, Reflection, and a New Teacher Education Program Author: Stevens, Dannelle D., Sarigul, Serap, Deger, Hulya Year: 2002 In Turkey there is an old saying about how parents feel about the role of schools: "The bones are mine, but the flesh is yours." Turkish parents want schools to not only educate but to mold and shape the values of their children in ways that the educators think appropriate. Ever since Turkey became a republic in 1923 under the leadership of Mustafa Kemal Ataturk, education has been highly valued. In 1924, Ataturk invited John Dewey to assess and report on the situation in Turkish schools. In Turkish villages, anyone with an education was highly respected. Old people stood up out of respect when a student returned to the village with a high school diploma or even better, a college degree. The saying echoes this blind trust in the ultimate authority and responsibility of schools to educate children. The primary purpose of this article is to report how Turkish student teachers identify and reflect on the "critical incidents" of schooling that they bring as they enter a new teacher education program. "Critical incidents" are descriptions of incidents in one's past that are viewed as significant in one's learning and development. The secondary purpose of this article is to analyze these incidents to inform the first author's teaching and field supervision. In this way, this study is an action research project designed to be a systematic study of her own practice of assessing the nature of students' background knowledge of teaching. Close

• 678. [Article] A study of deshive refining and its effects on high yield kraft pulp

  High yield unbleached kraft pulp for linerboard and bag paper was deshived in a PFI mill and a Bauer model 187 double disk refiner. Levels of plate gap, specific energy consumption, throughput rate, and ...

  Citation × Citation Citation Abstract Copy Title: A study of deshive refining and its effects on high yield kraft pulp Author: Knutsen, Daniel Peter High yield unbleached kraft pulp for linerboard and bag paper was deshived in a PFI mill and a Bauer model 187 double disk refiner. Levels of plate gap, specific energy consumption, throughput rate, and stock consistency were varied to control PFI mill and Bauer 187 deshive refining. Shive content reductions were accurately monitored with the von Alf than shives analyzer. Mathematical models expressing post-treatment von Alf than values in terms of the four control variables were proposed for both refining machines. The PFI mill was an effective deshive refiner, but a poor modeling base due to the insensitive response of shive content to changes in processing conditions. The Bauer 187 performed well as a deshive refiner and model base. A strong relationship was found between post-treatment von Alfthan values and Bauer 187 control variables. A best model of Bauer 187 deshive refining was selected by the total square error criterion. That model involves a complex relationship of plate gap, stock consistency, and throughput rate, but, in general, reducing plate gap and increasing stock consistency reduces post-treatment shive contents. Conditions which optimized the efficiency of Bauer 187 deshive refining depended upon the desired shive content of processed pulp. Shive contents typical of industrially deshived pulp were most efficiently obtained by Bauer 187 deshive refining at 1.5 mm plate gap, 1.2 kg/minute throughput rate, and 12 percent consistency. The effects of deshive refining on pulp washing and strength development potential were also investigated. Chemical recovery from high yield kraft pulp was improved by Bauer 187 deshive refining. Washing improvements became more pronounced as pulp yield was increased. Pulp strength at common levels of CSF and sheet bulk generally benefited from Bauer 187 deshive refining. Strength differences between deshived and undeshived pulps were attributable to differences in the amount of strength development beating necessary to achieve specified bulks and freenesses. Title: A study of deshive refining and its effects on high yield kraft pulp Author: Knutsen, Daniel Peter High yield unbleached kraft pulp for linerboard and bag paper was deshived in a PFI mill and a Bauer model 187 double disk refiner. Levels of plate gap, specific energy consumption, throughput rate, and stock consistency were varied to control PFI mill and Bauer 187 deshive refining. Shive content reductions were accurately monitored with the von Alf than shives analyzer. Mathematical models expressing post-treatment von Alf than values in terms of the four control variables were proposed for both refining machines. The PFI mill was an effective deshive refiner, but a poor modeling base due to the insensitive response of shive content to changes in processing conditions. The Bauer 187 performed well as a deshive refiner and model base. A strong relationship was found between post-treatment von Alfthan values and Bauer 187 control variables. A best model of Bauer 187 deshive refining was selected by the total square error criterion. That model involves a complex relationship of plate gap, stock consistency, and throughput rate, but, in general, reducing plate gap and increasing stock consistency reduces post-treatment shive contents. Conditions which optimized the efficiency of Bauer 187 deshive refining depended upon the desired shive content of processed pulp. Shive contents typical of industrially deshived pulp were most efficiently obtained by Bauer 187 deshive refining at 1.5 mm plate gap, 1.2 kg/minute throughput rate, and 12 percent consistency. The effects of deshive refining on pulp washing and strength development potential were also investigated. Chemical recovery from high yield kraft pulp was improved by Bauer 187 deshive refining. Washing improvements became more pronounced as pulp yield was increased. Pulp strength at common levels of CSF and sheet bulk generally benefited from Bauer 187 deshive refining. Strength differences between deshived and undeshived pulps were attributable to differences in the amount of strength development beating necessary to achieve specified bulks and freenesses. Close

• 679. [Article] 1/f noise of GaAs resistors on semi-insulating substrates, and 1/f noise due to temperature fluctuations in heat conduction

  This research work focuses on the mechanism of 1/f noise in GaAs resistors on semi-insulating substrates and 1/f noise due to temperature fluctuations in heat conduction in resistors, diodes, and bipolar ...

  Citation × Citation Citation Abstract Copy Title: 1/f noise of GaAs resistors on semi-insulating substrates, and 1/f noise due to temperature fluctuations in heat conduction Author: Choi, Mun-Seork, 1960- This research work focuses on the mechanism of 1/f noise in GaAs resistors on semi-insulating substrates and 1/f noise due to temperature fluctuations in heat conduction in resistors, diodes, and bipolar transistors. The goal of this research is to generate accurate models to explain physical origin of 1/f noise in semi-insulating substrate and semiconductor devices dissipating high power. The model is based on a distributed equivalent circuit representation of the substrate, and shows that 1/f noise bulk phenomena associated with high resistivity substrates. One consequence of the theory is that in this particular instance Hooge's parameter is given by a formula and it is not an empirical parameter. Power dissipation at high currents and voltages in semiconductor devices results in significant heat generation and heat conduction towards the heat sink. The device temperature is only an average value and there are as a consequence of the diffusion equation for heat flow itself temperature fluctuations about this average value. It will be shown that these temperature fluctuations can result in 1/f noise at moderately low frequencies where these frequencies are determined by the physical dimensions over which the heat flows and the diffusion transit time. The results are then related to the shot noise or white noise due to the collector current allowing a determination of the 1/f noise corner frequency. Title: 1/f noise of GaAs resistors on semi-insulating substrates, and 1/f noise due to temperature fluctuations in heat conduction Author: Choi, Mun-Seork, 1960- This research work focuses on the mechanism of 1/f noise in GaAs resistors on semi-insulating substrates and 1/f noise due to temperature fluctuations in heat conduction in resistors, diodes, and bipolar transistors. The goal of this research is to generate accurate models to explain physical origin of 1/f noise in semi-insulating substrate and semiconductor devices dissipating high power. The model is based on a distributed equivalent circuit representation of the substrate, and shows that 1/f noise bulk phenomena associated with high resistivity substrates. One consequence of the theory is that in this particular instance Hooge's parameter is given by a formula and it is not an empirical parameter. Power dissipation at high currents and voltages in semiconductor devices results in significant heat generation and heat conduction towards the heat sink. The device temperature is only an average value and there are as a consequence of the diffusion equation for heat flow itself temperature fluctuations about this average value. It will be shown that these temperature fluctuations can result in 1/f noise at moderately low frequencies where these frequencies are determined by the physical dimensions over which the heat flows and the diffusion transit time. The results are then related to the shot noise or white noise due to the collector current allowing a determination of the 1/f noise corner frequency. Close

• 680. [Article] MONTE CARLO SIMULATION OF ORANGE JUICE PECTINMETHYLESTERASE (PME) INACTIVATION BY COMBINED PROCESSES OF HIGH HYDROSTATIC PRESSURE (HHP) AND TEMPERATURE

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Universidad Autónoma Metropolitana Unidad Iztapalapa and can be found at: http:...

  Citation × Citation Citation Abstract Copy Title: MONTE CARLO SIMULATION OF ORANGE JUICE PECTINMETHYLESTERASE (PME) INACTIVATION BY COMBINED PROCESSES OF HIGH HYDROSTATIC PRESSURE (HHP) AND TEMPERATURE Author: Welti-Chanes, J., Torres, J. A., Serment-Moreno, V., Mujica-Paz, H. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Universidad Autónoma Metropolitana Unidad Iztapalapa and can be found at: http://www.redalyc.org/revista.oa?id=620. Title: MONTE CARLO SIMULATION OF ORANGE JUICE PECTINMETHYLESTERASE (PME) INACTIVATION BY COMBINED PROCESSES OF HIGH HYDROSTATIC PRESSURE (HHP) AND TEMPERATURE Author: Welti-Chanes, J., Torres, J. A., Serment-Moreno, V., Mujica-Paz, H. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Universidad Autónoma Metropolitana Unidad Iztapalapa and can be found at: http://www.redalyc.org/revista.oa?id=620. Close