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• 91. [Article] Determining the cost of old-growth set-asides on the OSU college forest

  The objectives for the use of the Oregon State University college forest include providing both facilities for research and teaching, and providing funding through timber harvest. The older age-classes ...

  Citation × Citation Citation Abstract Copy Title: Determining the cost of old-growth set-asides on the OSU college forest Author: Birch, Kevin R. The objectives for the use of the Oregon State University college forest include providing both facilities for research and teaching, and providing funding through timber harvest. The older age-classes of the forest are valuable for attaining both objectives. The opportunities and costs of removing acreage in the older age classes from the timber harvest base were examined. Harvest schedules were developed using a model II linear programming formulation with the OSU Forestry Model. The harvest schedules used the current management policies of the forest managers and different levels of set-asides with a non-declining even flow of volume constraining the harvest level. The current rotation age of 90 years was found to be constraining the harvest level in the first four decades, therefore a set of harvest scheduling runs using a 60 year rotation age were done. Using the existing management policies and a rotation age of 90 years, the managers of the college forest can set-aside the oldest 686 acres of the forest without reducing the current harvest level. The cost of the set-sides (calculated as the difference between present net values of 100 year harvest schedules with and without the acreage removed) was between $5500 and $4500 per acre depending on the amount of acreage removed. The change in rotation age produced only slight changes in the cost of set-asides. The current harvest level could be increased immediately to a level near long-term sustained yield by using a rotation age of 60 years. This would increase the present net value of the harvest schedule by about $5 million. By using a rotation age of 90, more age classes can be represented on the forest over time. After four decades the harvest volume can be increased to the long-term sustained yield level. At that time the harvest would be obtained from fewer acres than if the forest was on a 60 year rotation. Title: Determining the cost of old-growth set-asides on the OSU college forest Author: Birch, Kevin R. The objectives for the use of the Oregon State University college forest include providing both facilities for research and teaching, and providing funding through timber harvest. The older age-classes of the forest are valuable for attaining both objectives. The opportunities and costs of removing acreage in the older age classes from the timber harvest base were examined. Harvest schedules were developed using a model II linear programming formulation with the OSU Forestry Model. The harvest schedules used the current management policies of the forest managers and different levels of set-asides with a non-declining even flow of volume constraining the harvest level. The current rotation age of 90 years was found to be constraining the harvest level in the first four decades, therefore a set of harvest scheduling runs using a 60 year rotation age were done. Using the existing management policies and a rotation age of 90 years, the managers of the college forest can set-aside the oldest 686 acres of the forest without reducing the current harvest level. The cost of the set-sides (calculated as the difference between present net values of 100 year harvest schedules with and without the acreage removed) was between $5500 and $4500 per acre depending on the amount of acreage removed. The change in rotation age produced only slight changes in the cost of set-asides. The current harvest level could be increased immediately to a level near long-term sustained yield by using a rotation age of 60 years. This would increase the present net value of the harvest schedule by about $5 million. By using a rotation age of 90, more age classes can be represented on the forest over time. After four decades the harvest volume can be increased to the long-term sustained yield level. At that time the harvest would be obtained from fewer acres than if the forest was on a 60 year rotation. Close

• 92. [Article] Effects of maternal age on reproductive success in black rockfish, Sebastes melanops

  From 1996 through 1998 I collected mature female black rockfish off Oregon and examined ovaries and otoliths to estimate weekly, age-specific larval production. In all reproductive seasons, older black ...

  Citation × Citation Citation Abstract Copy Title: Effects of maternal age on reproductive success in black rockfish, Sebastes melanops Author: Bobko, Stephen J. From 1996 through 1998 I collected mature female black rockfish off Oregon and examined ovaries and otoliths to estimate weekly, age-specific larval production. In all reproductive seasons, older black rockfish extruded larvae earlier in the season, followed by progressively younger fish. Each year, beginning in May, I collected young-of-the-year (YOY) benthic juveniles that settled out in nearshore waters and determined their birthdates from counts of daily rings of lapillar otoliths. I compared the birthdate distribution of juvenile survivors to the age-specific temporal distribution of larval production to estimate the contribution of each adult female age group, ages 6-8, 9-11, 12-14, and 15+ to juvenile recruitment. The results from 1996 show a disproportionately greater contribution to benthic YOY recruitment by older fish. 1997 results show a relatively even contribution among maternal age groups. In 1998 most of the YOY recruits came from younger fish extruding larvae late in the season. I then examined larvae per recruit (LPR) models to evaluate the effects of fishing mortality on spawning potential of black rockfish, incorporating my estimates of age-specific maternal reproductive success. When it is evident that certain age groups are more successful at reproducing, as observed in black rockfish, changes in that population's age composition must be considered beyond simply reducing the estimate of total larval production. Title: Effects of maternal age on reproductive success in black rockfish, Sebastes melanops Author: Bobko, Stephen J. From 1996 through 1998 I collected mature female black rockfish off Oregon and examined ovaries and otoliths to estimate weekly, age-specific larval production. In all reproductive seasons, older black rockfish extruded larvae earlier in the season, followed by progressively younger fish. Each year, beginning in May, I collected young-of-the-year (YOY) benthic juveniles that settled out in nearshore waters and determined their birthdates from counts of daily rings of lapillar otoliths. I compared the birthdate distribution of juvenile survivors to the age-specific temporal distribution of larval production to estimate the contribution of each adult female age group, ages 6-8, 9-11, 12-14, and 15+ to juvenile recruitment. The results from 1996 show a disproportionately greater contribution to benthic YOY recruitment by older fish. 1997 results show a relatively even contribution among maternal age groups. In 1998 most of the YOY recruits came from younger fish extruding larvae late in the season. I then examined larvae per recruit (LPR) models to evaluate the effects of fishing mortality on spawning potential of black rockfish, incorporating my estimates of age-specific maternal reproductive success. When it is evident that certain age groups are more successful at reproducing, as observed in black rockfish, changes in that population's age composition must be considered beyond simply reducing the estimate of total larval production. Close

• 93. [Article] An analysis of the attitudes of traditional-aged and non-traditional-aged females about computers in word processing classes at Oregon's community colleges

  Today's office worker is being expected to operate computers in order to increase office productivity. While learning the new technology is a positive challenge for most people, some students experience ...

  Citation × Citation Citation Abstract Copy Title: An analysis of the attitudes of traditional-aged and non-traditional-aged females about computers in word processing classes at Oregon's community colleges Author: Fletcher, Judith Ann Today's office worker is being expected to operate computers in order to increase office productivity. While learning the new technology is a positive challenge for most people, some students experience a negative computer attitude when faced with computer training. This study sought to determine if there were significant differences about computer attitudes among females enrolled in introductory computer word processing classes in Oregon's community colleges. A sample of 125 traditional-aged females and 125 non-traditional-aged females was surveyed using the Computer Attitude Scale (CAS) developed by Brenda Loyd and Clarice Gressard. A t-test was used to compare groups on the CAS total scale and four subscales. No significant difference at the .05 level was found between the two groups on the total scores in the CAS. No significant differences were found on the two subscales: Computer Confidence and Computer Usefulness. However, on the Computer Anxiety Subscale, the non-traditional-aged group scored significantly lower than the traditional-aged group. There was also a significant difference on the Computer Liking subscale with the traditional-aged group scoring lower than the non-traditional-aged group. The implications of the study resulted in the recommendations that the instructors be alert to students' attitudes about computers as they are exposed to new office technology and that those instructors who gather, design, and scientifically test successful strategies in relieving negative attitudes share their methods with other teachers. It was also recommended that a correlation study between computer attitudes and word processing performance be made. Further recommendations for scientific studies included students' attitudes about technology other than word processing, the affect of age difference on students' attitudes, the affect of the amount of time of previous employment of students' attitudes, and the affect of previous computer experience on students' attitudes. Title: An analysis of the attitudes of traditional-aged and non-traditional-aged females about computers in word processing classes at Oregon's community colleges Author: Fletcher, Judith Ann Today's office worker is being expected to operate computers in order to increase office productivity. While learning the new technology is a positive challenge for most people, some students experience a negative computer attitude when faced with computer training. This study sought to determine if there were significant differences about computer attitudes among females enrolled in introductory computer word processing classes in Oregon's community colleges. A sample of 125 traditional-aged females and 125 non-traditional-aged females was surveyed using the Computer Attitude Scale (CAS) developed by Brenda Loyd and Clarice Gressard. A t-test was used to compare groups on the CAS total scale and four subscales. No significant difference at the .05 level was found between the two groups on the total scores in the CAS. No significant differences were found on the two subscales: Computer Confidence and Computer Usefulness. However, on the Computer Anxiety Subscale, the non-traditional-aged group scored significantly lower than the traditional-aged group. There was also a significant difference on the Computer Liking subscale with the traditional-aged group scoring lower than the non-traditional-aged group. The implications of the study resulted in the recommendations that the instructors be alert to students' attitudes about computers as they are exposed to new office technology and that those instructors who gather, design, and scientifically test successful strategies in relieving negative attitudes share their methods with other teachers. It was also recommended that a correlation study between computer attitudes and word processing performance be made. Further recommendations for scientific studies included students' attitudes about technology other than word processing, the affect of age difference on students' attitudes, the affect of the amount of time of previous employment of students' attitudes, and the affect of previous computer experience on students' attitudes. Close

• 94. [Image] 1999 Klamath River fall chinook age composition

  	Title taken from subject line ; "February 9, 2000."
  	Citation × Citation Citation Abstract Copy Title: 1999 Klamath River fall chinook age composition Year: 2000, 2005 Title taken from subject line ; "February 9, 2000." Title: 1999 Klamath River fall chinook age composition Year: 2000, 2005 Title taken from subject line ; "February 9, 2000." Close

• 95. [Article] Histologic and Morphometric Evaluation of Testes of Feral Tom Kittens and Cats

  Background: Even with numerous successful Trap-Neuter-Release programs, feral cat populations continue to grow. Our laboratory is interested in determining if an underlying biological cause exists for ...

  Citation × Citation Citation Abstract Copy Title: Histologic and Morphometric Evaluation of Testes of Feral Tom Kittens and Cats Author: Bohrer, Ellie R., Mihalyo, Anna Background: Even with numerous successful Trap-Neuter-Release programs, feral cat populations continue to grow. Our laboratory is interested in determining if an underlying biological cause exists for the exuberant reproductive success in this once domestic subspecies. An earlier age for developing reproductive capacity (onset of spermatogenesis in males) may be one factor. For domestic toms, puberty is reported to occur around 8 months of age. Previous work by our laboratory has shown that normal morphologic sperm are present in vas deferens secretions of feral toms before 6 months of age. Therefore, our hypothesis was that in feral toms the onset of spermatogenesis occurred before 6 months of age. The study objective was to histologically evaluate testes from weanling (2 months of age) through adulthood (24 months of age) to determine when the onset of spermatogenesis occurs in feral toms. Methods: Feral toms were presented for castration at a local Humane Society during August-October 2014. Age was determined by records provided from feral cat colony managers and confirmed with dental eruption patterns. The age groups were: 2-2.5 months (weanling; n=6), 3-4 months (juvenile; n=6), 5-6 months (pubertal; n=6), and 12-24 months (adult; n=6). General anesthesia was induced and a routine open castration was performed. Both testicles from each cat were hemi-sectioned, formalin-fixed, paraffin-embedded, cut into sections (6 µm), and stained with hematoxylin and eosin. The slides were evaluated by a single observer (EB) blinded to age group using bright field microscopy (200X). Evidence of spermatogenesis was determined on the basis of presence of spermatozoa in the seminiferous tubule lumen. In addition, perpendicular diameters measured from 5 tubules for each testis were averaged and mean ± SD was determined for each age group. Tubular diameter was compared using a Student’s t test where p < 0.05 was defined as significant. The presence of spermatozoa in the lumen was compared using a Chi-square test. Results: Evidence of spermatogenesis in weanling, juvenile, pubertal, and adult toms was 0%, 17%, 67%, and 100%, respectively (p < 0.05 between successive age groups). The seminiferous tubular diameter was significantly larger in each successive age group (weanlings 88.10 ± 10.88 µm; juveniles 109.8 ± 8.89 µm; pubertal 142.2 ± 16.89 µm; adult 237.90 ± 52.45 µm). Discussion: Juvenile feral toms in the current study had significantly wider tubular diameter than previously reported for domestic toms under 5 months of age (86 µm), which supports our hypothesis that spermatogenesis is occurring at an earlier age in ferals. However, the time of year the previous measurements in domestics was not reported. If these measurements were made outside of the breeding season, this may explain why the tubular diameters were smaller. Future studies are planned to determine if folliculogenesis occurs earlier in queens as well. Title: Histologic and Morphometric Evaluation of Testes of Feral Tom Kittens and Cats Author: Bohrer, Ellie R., Mihalyo, Anna Background: Even with numerous successful Trap-Neuter-Release programs, feral cat populations continue to grow. Our laboratory is interested in determining if an underlying biological cause exists for the exuberant reproductive success in this once domestic subspecies. An earlier age for developing reproductive capacity (onset of spermatogenesis in males) may be one factor. For domestic toms, puberty is reported to occur around 8 months of age. Previous work by our laboratory has shown that normal morphologic sperm are present in vas deferens secretions of feral toms before 6 months of age. Therefore, our hypothesis was that in feral toms the onset of spermatogenesis occurred before 6 months of age. The study objective was to histologically evaluate testes from weanling (2 months of age) through adulthood (24 months of age) to determine when the onset of spermatogenesis occurs in feral toms. Methods: Feral toms were presented for castration at a local Humane Society during August-October 2014. Age was determined by records provided from feral cat colony managers and confirmed with dental eruption patterns. The age groups were: 2-2.5 months (weanling; n=6), 3-4 months (juvenile; n=6), 5-6 months (pubertal; n=6), and 12-24 months (adult; n=6). General anesthesia was induced and a routine open castration was performed. Both testicles from each cat were hemi-sectioned, formalin-fixed, paraffin-embedded, cut into sections (6 µm), and stained with hematoxylin and eosin. The slides were evaluated by a single observer (EB) blinded to age group using bright field microscopy (200X). Evidence of spermatogenesis was determined on the basis of presence of spermatozoa in the seminiferous tubule lumen. In addition, perpendicular diameters measured from 5 tubules for each testis were averaged and mean ± SD was determined for each age group. Tubular diameter was compared using a Student’s t test where p < 0.05 was defined as significant. The presence of spermatozoa in the lumen was compared using a Chi-square test. Results: Evidence of spermatogenesis in weanling, juvenile, pubertal, and adult toms was 0%, 17%, 67%, and 100%, respectively (p < 0.05 between successive age groups). The seminiferous tubular diameter was significantly larger in each successive age group (weanlings 88.10 ± 10.88 µm; juveniles 109.8 ± 8.89 µm; pubertal 142.2 ± 16.89 µm; adult 237.90 ± 52.45 µm). Discussion: Juvenile feral toms in the current study had significantly wider tubular diameter than previously reported for domestic toms under 5 months of age (86 µm), which supports our hypothesis that spermatogenesis is occurring at an earlier age in ferals. However, the time of year the previous measurements in domestics was not reported. If these measurements were made outside of the breeding season, this may explain why the tubular diameters were smaller. Future studies are planned to determine if folliculogenesis occurs earlier in queens as well. Close

• 96. [Article] Capacitance-voltage analysis, SPICE modeling, and aging studies of AC thin-film electroluminescent devices

  Alternating-current thin-film electroluminescent (ACTFEL) devices are metal-insulator-semiconductorinsulator- metal (MISIM) structures which emit light under high field, pulsed excitation. One aspect of ...

  Citation × Citation Citation Abstract Copy Title: Capacitance-voltage analysis, SPICE modeling, and aging studies of AC thin-film electroluminescent devices Author: Davidson, James D. (James Douglas), 1960- Alternating-current thin-film electroluminescent (ACTFEL) devices are metal-insulator-semiconductorinsulator- metal (MISIM) structures which emit light under high field, pulsed excitation. One aspect of ACTFEL operation that is not well understood is the aging of such devices with operating time. One of the primary goals of this thesis is to characterize the kinetics of ACTFEL aging and to determine the associated activation energy which is then used as an aid in identifying the physical mechanism responsible for aging. Toward this end a new method, the capacitance-voltage (C-V) technique, for electrical characterization of ACTFEL devices is developed and refined. The threshold voltage ,Vth, total capacitance Ctot, and the insulator capacitance, Cthg, as well as some information about the relative interface state density are available from C-V analysis. SPICE simulation and a discrete ACTFEL model are used to verify and refine the C-V technique. The heart of the SPICE model is the standard ACTFEL circuit model which consists of three capacitors representing the phosphor and two insulator layers and a pair of back-to-back Zener diodes which account for conduction in the phosphor above threshold. Model enhancements are the inclusion of five resistances which account for 1) the resistance of the transparent conducting layer, Rito, 2)and 3) the bulk insulator resistances, R1 and R2, 4) the phosphor layer bulk resistance, R, and 5) a diode resistance, Rd, which is in series with the back-to-back Zener diodes and is termed a hot electron resistor since it is associated with the emission of electrons from interface trap states. The refined SPICE equivalent circuit is found to give good agreement with experimental C-V curves and with C-V curves generated using a discrete ACTFEL model which is built using discrete capacitors and Zener diodes. Aging experiments are conducted using the C-V technique to monitor the threshold voltage as a function of aging time over a temperature range of -50 °C to 80 °C. An incubation period, in which the threshold voltage is constant, occurs for temperatures below 20 °C but no incubation period is observed for temperatures above 20 °C. After the incubation period, if any exists, the threshold voltage increases logarithmically with time to a saturated value which is temperature-dependent; logarithmic and saturated aging are collectively referred to as constituting short-term aging. Short-term aging is characterized by Ctot, C8, and phosphor threshold voltage which are independent of aging time, rigid shifts in the C-V transition to higher threshold voltages with aging time, and decreases in the conduction and polarization charges with aging time. A kinetic analysis of the variable-temperature ACTFEL aging characteristics results in an activation energy of 0.2 eV. Such experimental observations lead to a model for ACTFEL aging in which conduction electrons are trapped in deep level, fixed charge states which arise from atomic rearrangement at the interface. This trapped charge reduces the polarization charge with a corresponding increase in the threshold voltage. Title: Capacitance-voltage analysis, SPICE modeling, and aging studies of AC thin-film electroluminescent devices Author: Davidson, James D. (James Douglas), 1960- Alternating-current thin-film electroluminescent (ACTFEL) devices are metal-insulator-semiconductorinsulator- metal (MISIM) structures which emit light under high field, pulsed excitation. One aspect of ACTFEL operation that is not well understood is the aging of such devices with operating time. One of the primary goals of this thesis is to characterize the kinetics of ACTFEL aging and to determine the associated activation energy which is then used as an aid in identifying the physical mechanism responsible for aging. Toward this end a new method, the capacitance-voltage (C-V) technique, for electrical characterization of ACTFEL devices is developed and refined. The threshold voltage ,Vth, total capacitance Ctot, and the insulator capacitance, Cthg, as well as some information about the relative interface state density are available from C-V analysis. SPICE simulation and a discrete ACTFEL model are used to verify and refine the C-V technique. The heart of the SPICE model is the standard ACTFEL circuit model which consists of three capacitors representing the phosphor and two insulator layers and a pair of back-to-back Zener diodes which account for conduction in the phosphor above threshold. Model enhancements are the inclusion of five resistances which account for 1) the resistance of the transparent conducting layer, Rito, 2)and 3) the bulk insulator resistances, R1 and R2, 4) the phosphor layer bulk resistance, R, and 5) a diode resistance, Rd, which is in series with the back-to-back Zener diodes and is termed a hot electron resistor since it is associated with the emission of electrons from interface trap states. The refined SPICE equivalent circuit is found to give good agreement with experimental C-V curves and with C-V curves generated using a discrete ACTFEL model which is built using discrete capacitors and Zener diodes. Aging experiments are conducted using the C-V technique to monitor the threshold voltage as a function of aging time over a temperature range of -50 °C to 80 °C. An incubation period, in which the threshold voltage is constant, occurs for temperatures below 20 °C but no incubation period is observed for temperatures above 20 °C. After the incubation period, if any exists, the threshold voltage increases logarithmically with time to a saturated value which is temperature-dependent; logarithmic and saturated aging are collectively referred to as constituting short-term aging. Short-term aging is characterized by Ctot, C8, and phosphor threshold voltage which are independent of aging time, rigid shifts in the C-V transition to higher threshold voltages with aging time, and decreases in the conduction and polarization charges with aging time. A kinetic analysis of the variable-temperature ACTFEL aging characteristics results in an activation energy of 0.2 eV. Such experimental observations lead to a model for ACTFEL aging in which conduction electrons are trapped in deep level, fixed charge states which arise from atomic rearrangement at the interface. This trapped charge reduces the polarization charge with a corresponding increase in the threshold voltage. Close

• 97. [Article] Age-fecundity relationships in the striped seaperch Embiotoca lateralis from Yaquina Bay, Oregon

  A study was conducted at Yaquina Bay, Oregon, to determine the age-fecundity relationships in the striped seaperch Embiotoca lateralis. A questionnaire was sent to California, Oregon, and Washington to ...

  Citation × Citation Citation Abstract Copy Title: Age-fecundity relationships in the striped seaperch Embiotoca lateralis from Yaquina Bay, Oregon Author: Swedberg, Stephen Ernferd A study was conducted at Yaquina Bay, Oregon, to determine the age-fecundity relationships in the striped seaperch Embiotoca lateralis. A questionnaire was sent to California, Oregon, and Washington to ascertain what regulations were in effect, and the value of the family Embiotocidae with regard to the sport and commercial harvest. The questionnaire revealed that no state maintained a systematic account of each species landed, and further life history data appeared desirable for sport and commercial species. Fish were collected from March 20 to August 21, 1960, with 140 females and 26 males being collected for analysis by hook and line or 125-foot experimental gill net. Scales were imprinted on cellulose acetate cards or mounted between glass slides, The catch was measured in centimeters of standard length and weighed in grams. From 123 females, 2, 654 embryos were obtained, and a maximum of 22 embryos per female was measured in millimeters of standard length. The estimated time of annulus formation in most scales was from March 15 to June 12. Second and third annuli were primarily laid down in March and April, with the probable peak of annulus formation for females of ages IV, V and VI in May. Length-frequencies were presented by age-class and sex. Eighty-one females of age-class III dominated the sample. Females of age-classes II and III attained greater average lengths than males. In age-class II, average weights for females were slightly greater than those for males. Both sexes generally mature for the first time in their third year of life. Length-weight, and length-number of embryos per female, for females of age-classes III-IV, were expressed by the regression equation Y[subscript c] = a+ b (X). High correlations for length-weight were ob- tained. Additional females were needed to evaluate that age when weights would digress. Females of age-class V produced the most embryos per unit increase in length; this rate declined in age-class VI. The largest number of embryos produced by an age class was 1, 431, in age-class III. The average number (in parentheses) of embryos produced per female of each age class, was: II ( 17); III (18); IV (21); V (30); VI (31) and VII (32). The most prolific female was seven years old and contained 45 embryos. Sixteen diminutive embryos were collected in 10 out of 128 mature females. Most older females were thought to have ovulated earlier than younger females, for their embryos were generally larger than embryos of younger females. However, embryos from younger females could reach the approximate mean size of embryos of older females, but at a later date. Birth of embryos began about June 12 and ended in late July. Embryos averaged about 50 mm in standard length at birth. Suggestions are given for management of the striped seaperch. Title: Age-fecundity relationships in the striped seaperch Embiotoca lateralis from Yaquina Bay, Oregon Author: Swedberg, Stephen Ernferd A study was conducted at Yaquina Bay, Oregon, to determine the age-fecundity relationships in the striped seaperch Embiotoca lateralis. A questionnaire was sent to California, Oregon, and Washington to ascertain what regulations were in effect, and the value of the family Embiotocidae with regard to the sport and commercial harvest. The questionnaire revealed that no state maintained a systematic account of each species landed, and further life history data appeared desirable for sport and commercial species. Fish were collected from March 20 to August 21, 1960, with 140 females and 26 males being collected for analysis by hook and line or 125-foot experimental gill net. Scales were imprinted on cellulose acetate cards or mounted between glass slides, The catch was measured in centimeters of standard length and weighed in grams. From 123 females, 2, 654 embryos were obtained, and a maximum of 22 embryos per female was measured in millimeters of standard length. The estimated time of annulus formation in most scales was from March 15 to June 12. Second and third annuli were primarily laid down in March and April, with the probable peak of annulus formation for females of ages IV, V and VI in May. Length-frequencies were presented by age-class and sex. Eighty-one females of age-class III dominated the sample. Females of age-classes II and III attained greater average lengths than males. In age-class II, average weights for females were slightly greater than those for males. Both sexes generally mature for the first time in their third year of life. Length-weight, and length-number of embryos per female, for females of age-classes III-IV, were expressed by the regression equation Y[subscript c] = a+ b (X). High correlations for length-weight were ob- tained. Additional females were needed to evaluate that age when weights would digress. Females of age-class V produced the most embryos per unit increase in length; this rate declined in age-class VI. The largest number of embryos produced by an age class was 1, 431, in age-class III. The average number (in parentheses) of embryos produced per female of each age class, was: II ( 17); III (18); IV (21); V (30); VI (31) and VII (32). The most prolific female was seven years old and contained 45 embryos. Sixteen diminutive embryos were collected in 10 out of 128 mature females. Most older females were thought to have ovulated earlier than younger females, for their embryos were generally larger than embryos of younger females. However, embryos from younger females could reach the approximate mean size of embryos of older females, but at a later date. Birth of embryos began about June 12 and ended in late July. Embryos averaged about 50 mm in standard length at birth. Suggestions are given for management of the striped seaperch. Close

• 98. [Article] Interactive video communication technology and successful aging in place : applying the selective optimization with compensation model

  This study utilized the theoretical framework of selective optimization with compensation (SOC) (Baltes, 1987; Baltes & Baltes, 1990) to interpret older adults' definitions about successful aging in place. ...

  Citation × Citation Citation Abstract Copy Title: Interactive video communication technology and successful aging in place : applying the selective optimization with compensation model Author: Yamamoto, Toshiko This study utilized the theoretical framework of selective optimization with compensation (SOC) (Baltes, 1987; Baltes & Baltes, 1990) to interpret older adults' definitions about successful aging in place. Factors contributing to successful aging in place, including the importance of social interaction and perceptions of the usefulness of interactive video communication technology (IVC) for achieving optimal levels of social interaction and successful aging in place, were also determined. Data were collected using a questionnaire, home-observation checklist, seven-day social interaction diary, and in-depth interviews. The sample consisted of 14 women and four men who were over 75 years of age and living in their own homes. The participants were predominantly white, educated, mobile, and in good health. All participants declared that they would like to continue living in their own homes as long as possible. More than two-thirds had lived for over 30 years in their homes. Three major themes emerged from this study: successful aging in place, social interaction, and usefulness of IVC for aging in place. Participants' definitions of successful aging in place included factors related to health, mobility, independence, control, solitude, affordability, comfort, and social interactions. Social interactions represented, in the respondents' opinions, a major factor for successful aging in place. The participants had an active social life, employing a variety of social communication means, from face-to-face interactions and telephone to computers. Their social activities included club memberships, church activities, informal interactions with family members and friends, and formal interactions, especially with health care providers. The participants in this study did not perceive the IVC technology as important for their aging in place in their current situations. However, the participants admitted that the IVC could be a useful tool for people with limited health and mobility to allow them to maintain social interactions and successfully age in place. The interpretation of the findings is as follows: at their actual level of activity and mobility, the participants selected particular ways of communication and optimized these means. The IVC was perceived as a compensation mechanism to be used when other communication means fail due to health and mobility problems. Title: Interactive video communication technology and successful aging in place : applying the selective optimization with compensation model Author: Yamamoto, Toshiko This study utilized the theoretical framework of selective optimization with compensation (SOC) (Baltes, 1987; Baltes & Baltes, 1990) to interpret older adults' definitions about successful aging in place. Factors contributing to successful aging in place, including the importance of social interaction and perceptions of the usefulness of interactive video communication technology (IVC) for achieving optimal levels of social interaction and successful aging in place, were also determined. Data were collected using a questionnaire, home-observation checklist, seven-day social interaction diary, and in-depth interviews. The sample consisted of 14 women and four men who were over 75 years of age and living in their own homes. The participants were predominantly white, educated, mobile, and in good health. All participants declared that they would like to continue living in their own homes as long as possible. More than two-thirds had lived for over 30 years in their homes. Three major themes emerged from this study: successful aging in place, social interaction, and usefulness of IVC for aging in place. Participants' definitions of successful aging in place included factors related to health, mobility, independence, control, solitude, affordability, comfort, and social interactions. Social interactions represented, in the respondents' opinions, a major factor for successful aging in place. The participants had an active social life, employing a variety of social communication means, from face-to-face interactions and telephone to computers. Their social activities included club memberships, church activities, informal interactions with family members and friends, and formal interactions, especially with health care providers. The participants in this study did not perceive the IVC technology as important for their aging in place in their current situations. However, the participants admitted that the IVC could be a useful tool for people with limited health and mobility to allow them to maintain social interactions and successfully age in place. The interpretation of the findings is as follows: at their actual level of activity and mobility, the participants selected particular ways of communication and optimized these means. The IVC was perceived as a compensation mechanism to be used when other communication means fail due to health and mobility problems. Close

• 99. [Article] Endocrinology of sex-linked-recessive dwarf White Leghorn chickens, Gallus Domesticus, with special reference to the thyroid

  A comparison of the various endocrine glands, in addition to other anatomical measurements, was made on 19 normal and 21 dwarf 2-3-month-old females and 20 normal and 20 dwarf 7-13-month-old females of ...

  Citation × Citation Citation Abstract Copy Title: Endocrinology of sex-linked-recessive dwarf White Leghorn chickens, Gallus Domesticus, with special reference to the thyroid Author: Mirosh, Larry Wayne A comparison of the various endocrine glands, in addition to other anatomical measurements, was made on 19 normal and 21 dwarf 2-3-month-old females and 20 normal and 20 dwarf 7-13-month-old females of the White Leghorn breed. At both ages, dwarfs weighed significantly less and had significantly shorter shanks than normals. Comb weight and comb area (L X H) were significantly larger in normals than in dwarfs 7-13 months of age, but no significant difference was found in the 2-3 month age group. Ovaries in the 2-3 month age group were heavier in normals than in dwarfs, due to greater gonadotropin secretion in relation to body size. The divergent results in weight of the hypophyses on an absolute and a relative-to-body-weight basis may be attributed to the algebraic sum of synthesis storage and liberation of hormones by this gland. Also, absolute and relative weights of the adrenals did not always coincide in both age groups, which may be attributed to environmental factors influencing the release of ACTH from the hypophysis. The normals had significantly heavier thyroids than dwarfs. on an absolute and on a relative weight basis at both ages, which does not necessarily indicate a hyper- or hypothyroid condition in the latter group of birds. Normals secreted significantly more thyroxine than dwarfs at 7-13 months of age; whereas, no significant difference was found between these two types of chickens at 2-3 months of age, as determined by epithelial cell height. The significantly smaller colloid and follicle diameter found in thyroids of dwarfs than of normals may be attributed to the lower gland weights in the former group. Bioassay of the hypophyses from these chickens was conducted in immature, hypophysectomized, female rats. Dwarfs did not differ significantly from normals in STH activity, according to the tibia test, body weight gain and tail length. Greater epiphyseal plate responses were obtained from hypophyses of growing chickens. Thymus weight varied with dosage, which is attributed to several hormones acting on this gland. The normals had a significantly higher hypophyseal ACTH content than dwarfs 2-3 months of age, which is believed to be due to the hormone content of the hypophyses at the time of removal, rather than to dwarfism. Also, the younger birds were observed to have a higher ACTH content than older birds, which may be due to storage of this hormone in the hypophysis during the growing period. Dwarfs did not differ significantly from normals in gonadotropic activity at both ages, as evaluated by ovary, oviduct and uterus weight response in the assay rats. However, the older birds were observed to have higher gonadotropic activity than younger birds, as determined by ovary, oviduct and uterine weight and vaginal openings in the rats. No significant difference in FSH content of the hypophyses of dwarfs and normals of both ages was found, using ovarian follicle diameter. Observation of the interstitial cells in the rat ovaries revealed no difference between dwarfs and normals at both age classifications in ICSH content. No significant difference in TSH activity between dwarfs and normals within each age group was found, based on thyroid weight in the rats. Also, dwarfs did not appear to differ from normals of both ages in measurements on epithelial cell height and colloid and follicle diameter. Lack of appreciable differences between the treated rats and the controls in these measurements on the thyroids would indicate that rats did not respond to avian TSH. Title: Endocrinology of sex-linked-recessive dwarf White Leghorn chickens, Gallus Domesticus, with special reference to the thyroid Author: Mirosh, Larry Wayne A comparison of the various endocrine glands, in addition to other anatomical measurements, was made on 19 normal and 21 dwarf 2-3-month-old females and 20 normal and 20 dwarf 7-13-month-old females of the White Leghorn breed. At both ages, dwarfs weighed significantly less and had significantly shorter shanks than normals. Comb weight and comb area (L X H) were significantly larger in normals than in dwarfs 7-13 months of age, but no significant difference was found in the 2-3 month age group. Ovaries in the 2-3 month age group were heavier in normals than in dwarfs, due to greater gonadotropin secretion in relation to body size. The divergent results in weight of the hypophyses on an absolute and a relative-to-body-weight basis may be attributed to the algebraic sum of synthesis storage and liberation of hormones by this gland. Also, absolute and relative weights of the adrenals did not always coincide in both age groups, which may be attributed to environmental factors influencing the release of ACTH from the hypophysis. The normals had significantly heavier thyroids than dwarfs. on an absolute and on a relative weight basis at both ages, which does not necessarily indicate a hyper- or hypothyroid condition in the latter group of birds. Normals secreted significantly more thyroxine than dwarfs at 7-13 months of age; whereas, no significant difference was found between these two types of chickens at 2-3 months of age, as determined by epithelial cell height. The significantly smaller colloid and follicle diameter found in thyroids of dwarfs than of normals may be attributed to the lower gland weights in the former group. Bioassay of the hypophyses from these chickens was conducted in immature, hypophysectomized, female rats. Dwarfs did not differ significantly from normals in STH activity, according to the tibia test, body weight gain and tail length. Greater epiphyseal plate responses were obtained from hypophyses of growing chickens. Thymus weight varied with dosage, which is attributed to several hormones acting on this gland. The normals had a significantly higher hypophyseal ACTH content than dwarfs 2-3 months of age, which is believed to be due to the hormone content of the hypophyses at the time of removal, rather than to dwarfism. Also, the younger birds were observed to have a higher ACTH content than older birds, which may be due to storage of this hormone in the hypophysis during the growing period. Dwarfs did not differ significantly from normals in gonadotropic activity at both ages, as evaluated by ovary, oviduct and uterus weight response in the assay rats. However, the older birds were observed to have higher gonadotropic activity than younger birds, as determined by ovary, oviduct and uterine weight and vaginal openings in the rats. No significant difference in FSH content of the hypophyses of dwarfs and normals of both ages was found, using ovarian follicle diameter. Observation of the interstitial cells in the rat ovaries revealed no difference between dwarfs and normals at both age classifications in ICSH content. No significant difference in TSH activity between dwarfs and normals within each age group was found, based on thyroid weight in the rats. Also, dwarfs did not appear to differ from normals of both ages in measurements on epithelial cell height and colloid and follicle diameter. Lack of appreciable differences between the treated rats and the controls in these measurements on the thyroids would indicate that rats did not respond to avian TSH. Close

• 100. [Article] The use of time by homemakers with children

  The purpose of the study was to find out how a group of faculty wives with children used their time and to investigate some factors in housing and equipment which might influence how they used their time. ...

  Citation × Citation Citation Abstract Copy Title: The use of time by homemakers with children Author: Meyer, Bonnie Martin The purpose of the study was to find out how a group of faculty wives with children used their time and to investigate some factors in housing and equipment which might influence how they used their time. A comparison was made between homemakers with two pre-school age children and homemakers with two school age children in the way they used their time. Following a letter of explanation of the study, the writer contacted the homemakers by phone to make an appointment to visit them. During this visit the writer obtained the information for the questionnaire and explained the time sheets. Twenty-four homemakers, 12 with pre-school children, and 12 with school-age children kept usable records for this study. The homemakers ranged in age from 21 to 62 years of age. All of the homemakers had attended college with 42 percent graduating and an additional 16.5 percent earning their master's degree. Two were registered nurses. Both groups averaged four years of work before marriage. The homemakers with pre-school children had been married an average of eight years while the homemakers with school age children had been married an average of 18 years. The children ranged in age from four months to 18 years old. The 12.5 percent of the families that did not own their own homes were all from the group with pre-school children. Although all of the homes were well equipped, the families that had been established the longest time had slightly more equipment. Half of the total group used time plans; the majority of the homemakers using time plans were homemakers with pre-school children. Homemakers in this study as well as previous studies most often listed food preparation as the homemaking activity they most enjoyed. Again, cleaning house was most often listed as the activity least enjoyed, followed by ironing. Improved housing, equipment, and methods have failed to change these attitudes in over a quarter of a century. The homemakers with pre-school children spent the greatest percentage of their time caring for children followed by meal preparation and clean-up; the homemakers with school age children spent the greatest percentage of their time on food preparation and clean-up. Both groups spent a little over two and a half hours on meal preparation and clean-up. Homemakers with school age children averaged 48 minutes a day on laundry, whereas homemakers with pre-school children averaged 70 minutes a day. Cleaning house averaged 63 minutes a day for homemakers with school age children and 45 minutes a day for homemakers with pre-school children. Homemakers with school age children averaged 39 minutes for shopping, whereas homemakers with pre-school children averaged 23 minutes. The homemakers with school age children averaged 8 hours and 45 minutes of rest per day, whereas the homemakers with pre-school children averaged 8 hours and 8 minutes. Homemakers with school age children spent more time eating meals, on personal care, and on entertaining and social activities, whereas homemakers with pre-school children derived much of their leisure time from unplanned coffee breaks and chatting with neighbors. Other than the great difference in the amount of time the two groups spent in caring for their children, (the homemakers with pre-school children spent 3 hours and 38 minutes while the homemakers with school age children spent 39 minutes), there was great similarity in the way the two groups used their time. Another finding is that there is little difference in the amount of time the homemaker spent on different homemaking activities at the time of this study in comparison to studies done during the past quarter of a century. Title: The use of time by homemakers with children Author: Meyer, Bonnie Martin The purpose of the study was to find out how a group of faculty wives with children used their time and to investigate some factors in housing and equipment which might influence how they used their time. A comparison was made between homemakers with two pre-school age children and homemakers with two school age children in the way they used their time. Following a letter of explanation of the study, the writer contacted the homemakers by phone to make an appointment to visit them. During this visit the writer obtained the information for the questionnaire and explained the time sheets. Twenty-four homemakers, 12 with pre-school children, and 12 with school-age children kept usable records for this study. The homemakers ranged in age from 21 to 62 years of age. All of the homemakers had attended college with 42 percent graduating and an additional 16.5 percent earning their master's degree. Two were registered nurses. Both groups averaged four years of work before marriage. The homemakers with pre-school children had been married an average of eight years while the homemakers with school age children had been married an average of 18 years. The children ranged in age from four months to 18 years old. The 12.5 percent of the families that did not own their own homes were all from the group with pre-school children. Although all of the homes were well equipped, the families that had been established the longest time had slightly more equipment. Half of the total group used time plans; the majority of the homemakers using time plans were homemakers with pre-school children. Homemakers in this study as well as previous studies most often listed food preparation as the homemaking activity they most enjoyed. Again, cleaning house was most often listed as the activity least enjoyed, followed by ironing. Improved housing, equipment, and methods have failed to change these attitudes in over a quarter of a century. The homemakers with pre-school children spent the greatest percentage of their time caring for children followed by meal preparation and clean-up; the homemakers with school age children spent the greatest percentage of their time on food preparation and clean-up. Both groups spent a little over two and a half hours on meal preparation and clean-up. Homemakers with school age children averaged 48 minutes a day on laundry, whereas homemakers with pre-school children averaged 70 minutes a day. Cleaning house averaged 63 minutes a day for homemakers with school age children and 45 minutes a day for homemakers with pre-school children. Homemakers with school age children averaged 39 minutes for shopping, whereas homemakers with pre-school children averaged 23 minutes. The homemakers with school age children averaged 8 hours and 45 minutes of rest per day, whereas the homemakers with pre-school children averaged 8 hours and 8 minutes. Homemakers with school age children spent more time eating meals, on personal care, and on entertaining and social activities, whereas homemakers with pre-school children derived much of their leisure time from unplanned coffee breaks and chatting with neighbors. Other than the great difference in the amount of time the two groups spent in caring for their children, (the homemakers with pre-school children spent 3 hours and 38 minutes while the homemakers with school age children spent 39 minutes), there was great similarity in the way the two groups used their time. Another finding is that there is little difference in the amount of time the homemaker spent on different homemaking activities at the time of this study in comparison to studies done during the past quarter of a century. Close