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• 2641. [Article] Fisher Responses to Variability in the Bering Sea Pollock Fishery

  Pollock recruitment and biomass in the Bering Sea has fluctuated in concert with environmental changes since the early 2000s. As pollock spatial distributions, densities, and abundances varied, fishers ...

  Citation × Citation Citation Abstract Copy Title: Fisher Responses to Variability in the Bering Sea Pollock Fishery Author: Haynie, Alan, Watson, Jordan Pollock recruitment and biomass in the Bering Sea has fluctuated in concert with environmental changes since the early 2000s. As pollock spatial distributions, densities, and abundances varied, fishers have adjusted their fishing behavior. Utilizing ~30,000 trips made by Bering Sea pollock catcher vessels from 2003 – 2014, we found strong correlations between the distances that vessels traveled and both pollock survey abundance and bottom temperatures. During colder years when waters drove pollock populations north (during the summer B season) and closer to the edge of the Bering Sea shelf, many vessels traveled farther, following fish and maintaining high catch per unit effort (CPUE), despite low pollock abundance. The temperature and abundance relationships remain difficult to disentangle, however, as recent warm years have all occurred in concert with abundant pollock. Without low abundance warm years for comparison, it is difficult to project the impacts of warming. However, if warm waters yield predicted poor recruitment, then pollock may require more effort, even when closer to port. This increased effort (decreased CPUE) represents an additional cost to fishers because vessels use significantly more fuel while fishing than while transiting. Longer trips offer complicated trade-offs for fishers. The far-ranging trips overall had statistically similar net earnings as the shorter trips, suggesting that the higher CPUEs offset the costs, but many vessels are unable to profitably make these longer trips. As climate changes further and variability of pollock populations is predicted to increase, understanding the ability of different vessels to adapt is critical for efficient management.  Title: Fisher Responses to Variability in the Bering Sea Pollock Fishery Author: Haynie, Alan, Watson, Jordan Pollock recruitment and biomass in the Bering Sea has fluctuated in concert with environmental changes since the early 2000s. As pollock spatial distributions, densities, and abundances varied, fishers have adjusted their fishing behavior. Utilizing ~30,000 trips made by Bering Sea pollock catcher vessels from 2003 – 2014, we found strong correlations between the distances that vessels traveled and both pollock survey abundance and bottom temperatures. During colder years when waters drove pollock populations north (during the summer B season) and closer to the edge of the Bering Sea shelf, many vessels traveled farther, following fish and maintaining high catch per unit effort (CPUE), despite low pollock abundance. The temperature and abundance relationships remain difficult to disentangle, however, as recent warm years have all occurred in concert with abundant pollock. Without low abundance warm years for comparison, it is difficult to project the impacts of warming. However, if warm waters yield predicted poor recruitment, then pollock may require more effort, even when closer to port. This increased effort (decreased CPUE) represents an additional cost to fishers because vessels use significantly more fuel while fishing than while transiting. Longer trips offer complicated trade-offs for fishers. The far-ranging trips overall had statistically similar net earnings as the shorter trips, suggesting that the higher CPUEs offset the costs, but many vessels are unable to profitably make these longer trips. As climate changes further and variability of pollock populations is predicted to increase, understanding the ability of different vessels to adapt is critical for efficient management.  Close

• 2642. [Article] Vitamin B₆ retention in all-beef and beef-soy loaves processed by two simulated food-service systems

  The effect of 0% (all-beef) and 30% replacement of beef by hydrated soy protein concentrate (beef-soy) on vitamin B₆ retention in meat loaves was investigated. Vitamin B₆, moisture, fat and nitrogen contents were ...

  Citation × Citation Citation Abstract Copy Title: Vitamin B₆ retention in all-beef and beef-soy loaves processed by two simulated food-service systems Author: Li, Yu-tsuan The effect of 0% (all-beef) and 30% replacement of beef by hydrated soy protein concentrate (beef-soy) on vitamin B₆ retention in meat loaves was investigated. Vitamin B₆, moisture, fat and nitrogen contents were determined in raw meat loaf mixtures, as well as in freshly baked, held, chilled and microwave reheated all-beef and beef-soy loaves. Baking time, internal temperature, weight of the loaves, and volume and weight of the drip were recorded. Retention of vitamin B₆ and heating losses of the all-beef and beef-soy loaves were calculated, based on the raw meat loaf samples. The beef-soy loaves required less time than the all-beef ones to reach an internal temperature of 74°C in a 177°C oven. Compared to the all-beef loaves, the weight of the beef-soy loaves was higher (P<0.05) and the volume of the drip was lower (P<0.05). The all-beef and beef-soy loaves were similar in fat and nitrogen content. Microwave reheating lowered (P<0.05) moisture in both all-beef and beef-soy loaves. Retention of vitamin B₆ in the all-beef and beef-soy loaves was affected by treatment. In freshly baked loaves approximately 91% of the vitamin B₆ was retained in the all-beef loaf, and 97% in the beef-soy ones. Additional losses of vitamin B₆ occurred during holding at 95°C for one hour followed by 70°C for 15 minutes: all-beef and beef-soy loaves, respectively, retained 80 and 89%. For the all-beef and beef-soy loaves, respectively, 88 and 94% of the vitamin B₆ was retained after chilled storage at 2.8°C for 24 hours; and 89 and 98% with microwave reheating for four minutes. For the freshly baked and held all-beef loaves, 4.3 and 5.7% of the vitamin B₆, respectively, was transferred to the drip; and for the beef-soy loaves 0.6 and 0.8% of the vitamin B₆ was recovered in the drip. Title: Vitamin B₆ retention in all-beef and beef-soy loaves processed by two simulated food-service systems Author: Li, Yu-tsuan The effect of 0% (all-beef) and 30% replacement of beef by hydrated soy protein concentrate (beef-soy) on vitamin B₆ retention in meat loaves was investigated. Vitamin B₆, moisture, fat and nitrogen contents were determined in raw meat loaf mixtures, as well as in freshly baked, held, chilled and microwave reheated all-beef and beef-soy loaves. Baking time, internal temperature, weight of the loaves, and volume and weight of the drip were recorded. Retention of vitamin B₆ and heating losses of the all-beef and beef-soy loaves were calculated, based on the raw meat loaf samples. The beef-soy loaves required less time than the all-beef ones to reach an internal temperature of 74°C in a 177°C oven. Compared to the all-beef loaves, the weight of the beef-soy loaves was higher (P<0.05) and the volume of the drip was lower (P<0.05). The all-beef and beef-soy loaves were similar in fat and nitrogen content. Microwave reheating lowered (P<0.05) moisture in both all-beef and beef-soy loaves. Retention of vitamin B₆ in the all-beef and beef-soy loaves was affected by treatment. In freshly baked loaves approximately 91% of the vitamin B₆ was retained in the all-beef loaf, and 97% in the beef-soy ones. Additional losses of vitamin B₆ occurred during holding at 95°C for one hour followed by 70°C for 15 minutes: all-beef and beef-soy loaves, respectively, retained 80 and 89%. For the all-beef and beef-soy loaves, respectively, 88 and 94% of the vitamin B₆ was retained after chilled storage at 2.8°C for 24 hours; and 89 and 98% with microwave reheating for four minutes. For the freshly baked and held all-beef loaves, 4.3 and 5.7% of the vitamin B₆, respectively, was transferred to the drip; and for the beef-soy loaves 0.6 and 0.8% of the vitamin B₆ was recovered in the drip. Close

• 2643. [Article] Changes in raspberry pigments during processing and storage

  The retention of pigments in processed raspberries is a function of the process method and conditions of subsequent storage. The presence of sucrose and the nature of the headspace gas also influences ...

  Citation × Citation Citation Abstract Copy Title: Changes in raspberry pigments during processing and storage Author: Daravingas, George Vasilios The retention of pigments in processed raspberries is a function of the process method and conditions of subsequent storage. The presence of sucrose and the nature of the headspace gas also influences the retention of the pigment. The effect of some of the above variables on the pigments was investigated. Variables imposed were: (1) concentration of syrup, (2) headspace gas atmosphere, (3) temperature, and (4) time of storage. Separation of the pigment of Willamette red raspberries and black raspberries was made by column chromatography and the pigments were analyzed. spectrophotometrically. The results showed the following: 1. The pigments of Willamette red raspberries consisted of four separate cyanins as based on the R [subscript f] values and characteristic wavelengths of maximum absorption. The pigments of black raspberries consisted of three fractions. 2. On the basis of R [subscript f] values and wavelengths of maximum absorption only two of the constituent fractions were the same. 3. The wavelength of maximum absorption of all the anthocyanins shifted towards shorter wavelengths after the first month of storage. 4. Time and temperature of storage and their interaction each contributed significantly to the destruction of the cyanin pigments. An increase in either variable resulted in a greater destruction of the pigments. 5. As the concentration of the ingoing syrup was increased, the amount of individual cyanins decreased. 6. Oxygen in the headspace gas was shown to be detrimental to the retention of the cyanins I, II, and IV of the Willamette raspberries and to cyanins II and III of the black raspberries. 7. Changes in the total pigment concentration were greatly influenced by the cyanin in greatest concentration in the species. 8. Heat processing destroyed approximately 20 percent of the pigments of the raspberries. Title: Changes in raspberry pigments during processing and storage Author: Daravingas, George Vasilios The retention of pigments in processed raspberries is a function of the process method and conditions of subsequent storage. The presence of sucrose and the nature of the headspace gas also influences the retention of the pigment. The effect of some of the above variables on the pigments was investigated. Variables imposed were: (1) concentration of syrup, (2) headspace gas atmosphere, (3) temperature, and (4) time of storage. Separation of the pigment of Willamette red raspberries and black raspberries was made by column chromatography and the pigments were analyzed. spectrophotometrically. The results showed the following: 1. The pigments of Willamette red raspberries consisted of four separate cyanins as based on the R [subscript f] values and characteristic wavelengths of maximum absorption. The pigments of black raspberries consisted of three fractions. 2. On the basis of R [subscript f] values and wavelengths of maximum absorption only two of the constituent fractions were the same. 3. The wavelength of maximum absorption of all the anthocyanins shifted towards shorter wavelengths after the first month of storage. 4. Time and temperature of storage and their interaction each contributed significantly to the destruction of the cyanin pigments. An increase in either variable resulted in a greater destruction of the pigments. 5. As the concentration of the ingoing syrup was increased, the amount of individual cyanins decreased. 6. Oxygen in the headspace gas was shown to be detrimental to the retention of the cyanins I, II, and IV of the Willamette raspberries and to cyanins II and III of the black raspberries. 7. Changes in the total pigment concentration were greatly influenced by the cyanin in greatest concentration in the species. 8. Heat processing destroyed approximately 20 percent of the pigments of the raspberries. Close

• 2644. [Article] A model for waterside oxidation of zircaloy fuel cladding in pressurized water reactors

  A model has been developed to predict the long-term oxidation rate of Zircaloy-4 for ex-reactor (autoclave) and in-reactor (PWR) environments and operating conditions. A computer program has been written ...

  Citation × Citation Citation Abstract Copy Title: A model for waterside oxidation of zircaloy fuel cladding in pressurized water reactors Author: Almarshad, Abdullah I. A. A model has been developed to predict the long-term oxidation rate of Zircaloy-4 for ex-reactor (autoclave) and in-reactor (PWR) environments and operating conditions. A computer program has been written to solve the oxygen diffusion equation by employing a fully implicit finite difference method for a one dimensional cylindrical geometry. The moving boundary of the oxide is treated by deriving a time dependent relationship to control the speed of the interface motion. New diffusion coefficients for the oxygen in the oxide film have been developed. The proposed diffusion coefficients are a function of temperature and oxygen concentration gradient in the oxide and are derived for both the pre-transition and post-transition regions. To include the in-reactor corrosion behavior, additional factors have been considered, specifically the influence of the heat flux on the oxide-metal interface temperature, the fast neutron flux effect on the acceleration of the corrosion rate, and the effect of the lithium hydroxide concentration on the enhancement of the corrosion rate. This model allows the prediction of the long-term oxidation weight gain and the oxide thickness on Zircaloy-4 in operating conditions which simulate the PWR conditions. The results obtained for ex-reactor (autoclave) and in-reactor oxidation are compared with experimental data existing in the literature. The predictions are found to be in good agreement with the experimental data. Title: A model for waterside oxidation of zircaloy fuel cladding in pressurized water reactors Author: Almarshad, Abdullah I. A. A model has been developed to predict the long-term oxidation rate of Zircaloy-4 for ex-reactor (autoclave) and in-reactor (PWR) environments and operating conditions. A computer program has been written to solve the oxygen diffusion equation by employing a fully implicit finite difference method for a one dimensional cylindrical geometry. The moving boundary of the oxide is treated by deriving a time dependent relationship to control the speed of the interface motion. New diffusion coefficients for the oxygen in the oxide film have been developed. The proposed diffusion coefficients are a function of temperature and oxygen concentration gradient in the oxide and are derived for both the pre-transition and post-transition regions. To include the in-reactor corrosion behavior, additional factors have been considered, specifically the influence of the heat flux on the oxide-metal interface temperature, the fast neutron flux effect on the acceleration of the corrosion rate, and the effect of the lithium hydroxide concentration on the enhancement of the corrosion rate. This model allows the prediction of the long-term oxidation weight gain and the oxide thickness on Zircaloy-4 in operating conditions which simulate the PWR conditions. The results obtained for ex-reactor (autoclave) and in-reactor oxidation are compared with experimental data existing in the literature. The predictions are found to be in good agreement with the experimental data. Close

• 2645. [Article] Impact of Climate and Disturbance on the Formation of Earlywood and Latewood in Douglas-fir at the Salal Fields Study Site

  Wood density is controlled to a large extent by the relative widths of earlywood and latewood in the stem, but the mechanisms controlling these amounts are poorly understood in coastal Douglas-fir. To ...

  Citation × Citation Citation Abstract Copy Title: Impact of Climate and Disturbance on the Formation of Earlywood and Latewood in Douglas-fir at the Salal Fields Study Site Author: Gourley, Derek M. F. Wood density is controlled to a large extent by the relative widths of earlywood and latewood in the stem, but the mechanisms controlling these amounts are poorly understood in coastal Douglas-fir. To understand the role of climatic factors, one hundred and thirty-six increment cores were collected and measured from the Salal Fields study site located in Western Oregon. Increment cores were collected from the four following heights on 38 Douglas-fir trees representing differing social positions: 1.37, 2.44, 4.88, and 7.01 m. A master chronology was constructed using the median earlywood and latewood time series for all of the increment cores collected. Statistical models indicated that earlywood growth was impacted most by temperature, while latewood growth was impacted most by the amount of summer precipitation. The site experienced disturbance events, which impacted earlywood growth in 1980 and latewood growth in 1983. The majority of variation in the master chronologies of both earlywood and latewood for this site can be explained by changes in climate and the presence of disturbance events. Title: Impact of Climate and Disturbance on the Formation of Earlywood and Latewood in Douglas-fir at the Salal Fields Study Site Author: Gourley, Derek M. F. Wood density is controlled to a large extent by the relative widths of earlywood and latewood in the stem, but the mechanisms controlling these amounts are poorly understood in coastal Douglas-fir. To understand the role of climatic factors, one hundred and thirty-six increment cores were collected and measured from the Salal Fields study site located in Western Oregon. Increment cores were collected from the four following heights on 38 Douglas-fir trees representing differing social positions: 1.37, 2.44, 4.88, and 7.01 m. A master chronology was constructed using the median earlywood and latewood time series for all of the increment cores collected. Statistical models indicated that earlywood growth was impacted most by temperature, while latewood growth was impacted most by the amount of summer precipitation. The site experienced disturbance events, which impacted earlywood growth in 1980 and latewood growth in 1983. The majority of variation in the master chronologies of both earlywood and latewood for this site can be explained by changes in climate and the presence of disturbance events. Close

• 2646. [Article] Ecological relationships among western Ephemerellidae : growth, life cycles, food habits, and habitat relationships

  The purpose of this study was to describe the life cycles, feeding ecology, and habitat use of western species in the mayfly family Ephemerellidae. Data were used to compare the ecological relationships ...

  Citation × Citation Citation Abstract Copy Title: Ecological relationships among western Ephemerellidae : growth, life cycles, food habits, and habitat relationships Author: Hawkins, Charles Patrick The purpose of this study was to describe the life cycles, feeding ecology, and habitat use of western species in the mayfly family Ephemerellidae. Data were used to compare the ecological relationships and strategies among species and to examine patterns of adaptive radiation within the family. Data were further used to develop hypotheses describing the general importance of food, temperature, habitat, and season in affecting the development and organization of benthic invertebrate communities in stream ecosystems. Growth rate and length of growth period were examined in nine species. Growth rates of most species were related to temperature, but little evidence was found that implicated food as an important factor affecting individual growth in the field. Growth period and final size were most clearly related to specialization of different species for habitats that differ in duration of stability. Both food specialists and generalists were found among 20 species examined for gut contents. Proportion of detritus, diatoms, animal matter, and moss ingested varied among species. Within a species, diet varied with both locality and habitat, but these differences were not sufficient to mask differences in diet among species. Among 14 species, taxa varied in their distribution along a stream continuum (2nd to 7th order) and in their preference for gravel, cobble, boulder, or moss substrates. Most species were habitat specialists and occurred on only one or two substrate types and at only a few stations. When four niche dimensions were considered, overlap between species was found to be least for station, followed by substrate type, season, and food. Complementarity in niche overlaps between niche axes was found for species in the genus Drunella but not among species in the family as a whole. From this study I inferred that stream insects show similar patterns of resource use as do animals in other ecosystems, although evidence for a discrete guild substructure was not strong. I conclude by stressing the need for further research that examines how the multiple and interacting factors in stream ecosystems have shaped both the ecology of single species and the structure of entire communities. Title: Ecological relationships among western Ephemerellidae : growth, life cycles, food habits, and habitat relationships Author: Hawkins, Charles Patrick The purpose of this study was to describe the life cycles, feeding ecology, and habitat use of western species in the mayfly family Ephemerellidae. Data were used to compare the ecological relationships and strategies among species and to examine patterns of adaptive radiation within the family. Data were further used to develop hypotheses describing the general importance of food, temperature, habitat, and season in affecting the development and organization of benthic invertebrate communities in stream ecosystems. Growth rate and length of growth period were examined in nine species. Growth rates of most species were related to temperature, but little evidence was found that implicated food as an important factor affecting individual growth in the field. Growth period and final size were most clearly related to specialization of different species for habitats that differ in duration of stability. Both food specialists and generalists were found among 20 species examined for gut contents. Proportion of detritus, diatoms, animal matter, and moss ingested varied among species. Within a species, diet varied with both locality and habitat, but these differences were not sufficient to mask differences in diet among species. Among 14 species, taxa varied in their distribution along a stream continuum (2nd to 7th order) and in their preference for gravel, cobble, boulder, or moss substrates. Most species were habitat specialists and occurred on only one or two substrate types and at only a few stations. When four niche dimensions were considered, overlap between species was found to be least for station, followed by substrate type, season, and food. Complementarity in niche overlaps between niche axes was found for species in the genus Drunella but not among species in the family as a whole. From this study I inferred that stream insects show similar patterns of resource use as do animals in other ecosystems, although evidence for a discrete guild substructure was not strong. I conclude by stressing the need for further research that examines how the multiple and interacting factors in stream ecosystems have shaped both the ecology of single species and the structure of entire communities. Close

• 2647. [Article] Characterization of Oregon-derived malo-lactic bacteria : fermentation properties and storage stability

  Gram positive cocci isolated from Oregon wines were characterized and their relative malate fermentation abilities compared. They were heterofermentative, catalase negative, and facultatively anaerobic. ...

  Citation × Citation Citation Abstract Copy Title: Characterization of Oregon-derived malo-lactic bacteria : fermentation properties and storage stability Author: Dohman, Thomas Philip Gram positive cocci isolated from Oregon wines were characterized and their relative malate fermentation abilities compared. They were heterofermentative, catalase negative, and facultatively anaerobic. Glucose, fructose, cellobiose, maltose, ribose, trehalose, salicin and esculin were fermented by all strains. Arabinose was fermented weakly but lactose, raffinose, sucrose, xylose, rhamnose, mannose and glycerol were not fermented. Dextran was not produced from sucrose nor ammonia from arginine. The isolates grew well in a tomato/vegetable juice medium and fermented malate to lactate as detected by chromatography. Optimum growth temperatures ranged between 28 and 31 °C and generation times between 5.2 and 18.7 were observed at pH 5.5. The PH optimum ranged between 4.5 and 5.75. Growth was obtained in artificial media containing 14% ethanol and at pH values lower than 3.3. These malo-lactic bacteria were considered to be strains of Leuconostoc oenos. Malate fermentation rates indicated that these isolates effected a more rapid and complete malo-lactic fermentation than reference Leuconostoc strains. This was found in both artificial media at pH 3.5 and in Pinot Noir wine, pH 3.45. Levels of 30 ppm free sulfur dioxide and 0.6 g/L fumaric acid were observed to inhibit growth. Stability of cryopreserved cultures were studied over extended storage. Following 3 months storage of frozen concentrates at -20 and -40°C, survival rates of 70 to 80% were achieved using a modified Rogosa medium plus 15% glycerol. Following 2 months storage of lyophilized concentrates at room temperature, survival rates of 35 to 60% were achieved in milk (11% solids). Title: Characterization of Oregon-derived malo-lactic bacteria : fermentation properties and storage stability Author: Dohman, Thomas Philip Gram positive cocci isolated from Oregon wines were characterized and their relative malate fermentation abilities compared. They were heterofermentative, catalase negative, and facultatively anaerobic. Glucose, fructose, cellobiose, maltose, ribose, trehalose, salicin and esculin were fermented by all strains. Arabinose was fermented weakly but lactose, raffinose, sucrose, xylose, rhamnose, mannose and glycerol were not fermented. Dextran was not produced from sucrose nor ammonia from arginine. The isolates grew well in a tomato/vegetable juice medium and fermented malate to lactate as detected by chromatography. Optimum growth temperatures ranged between 28 and 31 °C and generation times between 5.2 and 18.7 were observed at pH 5.5. The PH optimum ranged between 4.5 and 5.75. Growth was obtained in artificial media containing 14% ethanol and at pH values lower than 3.3. These malo-lactic bacteria were considered to be strains of Leuconostoc oenos. Malate fermentation rates indicated that these isolates effected a more rapid and complete malo-lactic fermentation than reference Leuconostoc strains. This was found in both artificial media at pH 3.5 and in Pinot Noir wine, pH 3.45. Levels of 30 ppm free sulfur dioxide and 0.6 g/L fumaric acid were observed to inhibit growth. Stability of cryopreserved cultures were studied over extended storage. Following 3 months storage of frozen concentrates at -20 and -40°C, survival rates of 70 to 80% were achieved using a modified Rogosa medium plus 15% glycerol. Following 2 months storage of lyophilized concentrates at room temperature, survival rates of 35 to 60% were achieved in milk (11% solids). Close

• 2648. [Article] Selected life history aspects of American shad (Alosa sapidissima) and predation on young-of-the-year shad in Lake Umatilla of the Columbia River

  Selected life history aspects of American shad, Alosa sapidissima, collected in Lake Umatilla of the Columbia River during 1980 and 1981 were examined and compared to other shad populations. Mean fork ...

  Citation × Citation Citation Abstract Copy Title: Selected life history aspects of American shad (Alosa sapidissima) and predation on young-of-the-year shad in Lake Umatilla of the Columbia River Author: Stainbrook, Cris Eric Selected life history aspects of American shad, Alosa sapidissima, collected in Lake Umatilla of the Columbia River during 1980 and 1981 were examined and compared to other shad populations. Mean fork lengths of adult shad captured in 1981 were 405-, 415- and 423-mm for age III, IV and V males; 425-, 444- and 457-mm for age III, IV and V females. The mean age at maturity was determined to be 3.2 years for males and 3.5 years for females while the rate of repeat spawning was 36% and 45% for males and females, respectively. Four-year-old shad accounted for 58.5% of the spawning adults in the two years. Absolute fecundity ranged from 97,168 to 284,240 eggs with a mean of 193,074 eggs per female. Young-of-the-year shad were more abundant in 1980 than in 1981. In both years, the tail-race zone was the most important spawning area and the island zone the most important rearing area for young-of-the-year shad in the reservoir. Growth of young shad in Lake Umatilla was similar in all sampled macrohabitats and appears to be dependent on year class strength, water temperature and water flow. Out-migrating young-of-the-yetar shad passing through John Day Dam were significantly largjer than young-of-the-year shad in reservoir habitats indicating size, as well as temperature, influences the timing of downstream migration. Predation on young shad by resident predator fish species was variable and appeared to be dependent on the Abundance of young-of-the-year shad. Title: Selected life history aspects of American shad (Alosa sapidissima) and predation on young-of-the-year shad in Lake Umatilla of the Columbia River Author: Stainbrook, Cris Eric Selected life history aspects of American shad, Alosa sapidissima, collected in Lake Umatilla of the Columbia River during 1980 and 1981 were examined and compared to other shad populations. Mean fork lengths of adult shad captured in 1981 were 405-, 415- and 423-mm for age III, IV and V males; 425-, 444- and 457-mm for age III, IV and V females. The mean age at maturity was determined to be 3.2 years for males and 3.5 years for females while the rate of repeat spawning was 36% and 45% for males and females, respectively. Four-year-old shad accounted for 58.5% of the spawning adults in the two years. Absolute fecundity ranged from 97,168 to 284,240 eggs with a mean of 193,074 eggs per female. Young-of-the-year shad were more abundant in 1980 than in 1981. In both years, the tail-race zone was the most important spawning area and the island zone the most important rearing area for young-of-the-year shad in the reservoir. Growth of young shad in Lake Umatilla was similar in all sampled macrohabitats and appears to be dependent on year class strength, water temperature and water flow. Out-migrating young-of-the-yetar shad passing through John Day Dam were significantly largjer than young-of-the-year shad in reservoir habitats indicating size, as well as temperature, influences the timing of downstream migration. Predation on young shad by resident predator fish species was variable and appeared to be dependent on the Abundance of young-of-the-year shad. Close

• 2649. [Article] Pheromone-mediated behavior of adult Douglas-fir tussock moths, Orgyia pseudotsugata (McD.) (Lepidoptera: Lymantriidae)

  The sinuous flight behavior of male Douglas-fir tussock moths, Orgyia pseudotsugata, (McD.), is characterized by positive anemotaxis and positive chemoklinotaxis and varies depending on distance from the ...

  Citation × Citation Citation Abstract Copy Title: Pheromone-mediated behavior of adult Douglas-fir tussock moths, Orgyia pseudotsugata (McD.) (Lepidoptera: Lymantriidae) Author: Swaby, James Archie The sinuous flight behavior of male Douglas-fir tussock moths, Orgyia pseudotsugata, (McD.), is characterized by positive anemotaxis and positive chemoklinotaxis and varies depending on distance from the pheromone source, population density, and time of day. Visual cues play a minor role in close-range orientation to a pheromone source, but males do respond to heat energy equivalent to the internal body temperature of the females. A female may be simultaneously courted by two or more males, and a male may remain by the female after mating. Males and females can mate more than once, and there appears to be a minimum time-span which must elapse between consecutive matings by the same male. This probably limits males to one mating per evening. Egg viability is the same for single and multiple matings. Mated females wait for a period of time before laying their eggs and may interrupt oviposition to mate again. An unmated female may lay a portion of her eggs before mating or complete oviposition without copulating. Comparisons of average elapsed courtship, copulation, preoviposition (the period between copulation and egg laying) and oviposition times for laboratory-reared and wild New Mexico moths revealed that pre-oviposition is longer in laboratory moths; but courtship, copulation, and oviposition are the same. Under the prevailing field study conditions, females lived up to seven days but their ability to attract males dropped after three days and the probability that they would mate dropped after two days. Attractancy of male flight is also influenced by temperature and the inhibitory effect of rainy weather. The decline in attractancy is due to a reduction in the amount of pheromone present and a loss of the ability to release the pheromone. Furthermore, at least 20% of the unmated females were not attractive. Title: Pheromone-mediated behavior of adult Douglas-fir tussock moths, Orgyia pseudotsugata (McD.) (Lepidoptera: Lymantriidae) Author: Swaby, James Archie The sinuous flight behavior of male Douglas-fir tussock moths, Orgyia pseudotsugata, (McD.), is characterized by positive anemotaxis and positive chemoklinotaxis and varies depending on distance from the pheromone source, population density, and time of day. Visual cues play a minor role in close-range orientation to a pheromone source, but males do respond to heat energy equivalent to the internal body temperature of the females. A female may be simultaneously courted by two or more males, and a male may remain by the female after mating. Males and females can mate more than once, and there appears to be a minimum time-span which must elapse between consecutive matings by the same male. This probably limits males to one mating per evening. Egg viability is the same for single and multiple matings. Mated females wait for a period of time before laying their eggs and may interrupt oviposition to mate again. An unmated female may lay a portion of her eggs before mating or complete oviposition without copulating. Comparisons of average elapsed courtship, copulation, preoviposition (the period between copulation and egg laying) and oviposition times for laboratory-reared and wild New Mexico moths revealed that pre-oviposition is longer in laboratory moths; but courtship, copulation, and oviposition are the same. Under the prevailing field study conditions, females lived up to seven days but their ability to attract males dropped after three days and the probability that they would mate dropped after two days. Attractancy of male flight is also influenced by temperature and the inhibitory effect of rainy weather. The decline in attractancy is due to a reduction in the amount of pheromone present and a loss of the ability to release the pheromone. Furthermore, at least 20% of the unmated females were not attractive. Close

• 2650. [Article] Design, fabrication, and characterization of the laser-imaged natural circulation (LINC) facility

  Currently there is a great amount of interest in the phenomena of natural circulation as a cooling mechanism for normal operation as well as emergency conditions in nuclear reactors and spent fuel pools. ...

  Citation × Citation Citation Abstract Copy Title: Design, fabrication, and characterization of the laser-imaged natural circulation (LINC) facility Author: Goodrich, Sam S. Currently there is a great amount of interest in the phenomena of natural circulation as a cooling mechanism for normal operation as well as emergency conditions in nuclear reactors and spent fuel pools. In order to better understand this phenomena for the specific geometry of vertical, heated rods in water, an experimental facility was designed and constructed at Oregon State University. This facility, named the Laser-Imaged Natural Circulation (LINC) facility, consists of a water tank capped with a custom cooling plate through which two heated rods pass into the tank. The LINC facility enables flow patterns in the channel between the heated rods to be imaged and quantified using particle image velocimetry (PIV). This paper presents the reasoning and theory behind the design of the LINC facility, as well as a characterization of the thermodynamics, boundary layer thickness and velocity profile progression of the system. The thermodynamic analysis consists of bulk equilibrium temperatures and heat removal rates for 3 cases where the two heater rods have equal power levels (dubbed "symmetrical heating"). The boundary layer thickness analysis consists of a test matrix of 5 test cases including symmetrical and asymmetrical heating in which the thickness of the boundary layer is measured using the velocity field between the heater rods. The velocity profile analysis centered on an effective vertical length of 100 mm along the entrance region between the two rods at one symmetrical rod power. In addition to these experiments, additional synthesis of data regarding the dependence of the Nusselt number on the Rayleigh number along with temperature profile of the boundary layer were collected and presented. Title: Design, fabrication, and characterization of the laser-imaged natural circulation (LINC) facility Author: Goodrich, Sam S. Currently there is a great amount of interest in the phenomena of natural circulation as a cooling mechanism for normal operation as well as emergency conditions in nuclear reactors and spent fuel pools. In order to better understand this phenomena for the specific geometry of vertical, heated rods in water, an experimental facility was designed and constructed at Oregon State University. This facility, named the Laser-Imaged Natural Circulation (LINC) facility, consists of a water tank capped with a custom cooling plate through which two heated rods pass into the tank. The LINC facility enables flow patterns in the channel between the heated rods to be imaged and quantified using particle image velocimetry (PIV). This paper presents the reasoning and theory behind the design of the LINC facility, as well as a characterization of the thermodynamics, boundary layer thickness and velocity profile progression of the system. The thermodynamic analysis consists of bulk equilibrium temperatures and heat removal rates for 3 cases where the two heater rods have equal power levels (dubbed "symmetrical heating"). The boundary layer thickness analysis consists of a test matrix of 5 test cases including symmetrical and asymmetrical heating in which the thickness of the boundary layer is measured using the velocity field between the heater rods. The velocity profile analysis centered on an effective vertical length of 100 mm along the entrance region between the two rods at one symmetrical rod power. In addition to these experiments, additional synthesis of data regarding the dependence of the Nusselt number on the Rayleigh number along with temperature profile of the boundary layer were collected and presented. Close