The overall objective of this thesis was to improve our understanding of the light environment associated with two of the major deciduous competitors of commercial conifer seedlings in low elevation coastal British Columbia, and the physiological response of young conifers to specific environments and changes in the environment. Studies were conducted to investigate: 1) seasonal and herbicide-induced changes in the light regimes beneath the canopies of two brush species, 2) growth and physiology of seedlings of three conifer species in several different deciduous brush environments throughout the year, and 3) changes in the physiology and growth of suppressed conifer saplings when different methods and schedules were used to reduce shading from an overtopping red alder canopy. Seasonal changes in the light quantity and quality were documented within salmonberry (Rubus spectabilis Pursch) and below red alder (Alnus rubra Bong.) canopies. The prediction of light attenuation within salmonberry canopies using the Beer-Lambert law was good for foliated canopies using leaf area index, and defoliated canopies using stem area index. As salmonberry leaf area increased, the ratio of red to far-red light declined exponentially. Growth of grand fir (Abies qrandis (Dougl.) Forbes), western hemlock (Tsuga heterophylla (Raf.) Sarg.) and Douglas-fir (Pseudetsuga menziesii (Mirbel) Franco) seedlings decreased with increases in the canopy density of overtopping deciduous species. Physiological differences between conifer species and differences between overtopping canopy treatments declined in the autumn and winter. Based on the physiological measurements, suppression of the shade intolerant Douglas-fir seedlings was greatly reduced during the period that overtopping deciduous canopies were leafless. Animal damage reduces growth and probably increases the duration seedlings are under overtopping canopies. Suppressed Douglas-fir saplings released from overtopping by red alder canopies showed the greatest growth response when the alder canopies were removed in the spring; complete removal of the alder canopy during the summer had a predictably deleterious effect on the sapling physiology and growth. Herbicide injections resulted in a slower but predictable increase in conifer growth. / Forestry, Faculty of / Graduate

No description available.

Red interior lighting used to preserve dark-adaptation needs to be replaced in military applications by blue/green lighting which is not detectable by 3rd-generation image intensifiers. This study investigated the influence of blue/green as compared to red and white light of equal photopic intensity on subsequent visual acuity , contrast sensitivity and dark-adaptation. Male subjects (n = 90) were assigned to one of 15 treatment conditions (n = 6) as determined by the colour (blue/green, red or white) and intensity (0.1; 0.4; 1.6; 6.4 and 25.6 cd/m²) of the pre-adaptation stimuli. A modified Goldmann/Weekers adaptometer was used to present the preadaptation stimuli, test stimuli and record visual (luminance) thresholds of each subject. Blue/green lighting had the same affect on visual (photopic) acuity and contrast sensitivity as white and red lighting. Blue/green affected visual (absolute) threshold at the start and during the process of dark-adaptation in the same manner as white but not the same as red lighting. White and red lighting did not differ significantly (p < 0.01) at low intensities (mesopic range) but did at the higher intensities (photopic range). After exposure to blue/green and white light, it will take longer to reach the same level of dark-adaptation than after exposure to red. These time differences increase with" increased intensities. The brightness ratio between red and white lights to produce the same dark-adaptation increases with an increase in intensity. At the upper mesopic region the differences between the effects of white and red lighting on subsequent dark-adaptation become irregular due to the inability to accurately equate non-monochromatic lights in the mesopic range.

viii, 61 leaves : ill. ; 28 cm Typescript. (Another copy on microfilm is located in Archives) Thesis (M.S.)--University of Oregon Includes vita and abstract Bibliography: leaves 57-61 University of Oregon theses, Dept. of Biology, M.S., 1980

Made available in DSpace on 2014-11-10T11:09:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-02-18Bitstream added on 2014-11-10T11:57:30Z : No. of bitstreams: 1 000790208_20160218.pdf: 1204228 bytes, checksum: 10f416eb0759a57de353af13f253e5a5 (MD5) Bitstreams deleted on 2016-02-18T10:00:17Z: 000790208_20160218.pdf,. Added 1 bitstream(s) on 2016-02-18T10:01:03Z : No. of bitstreams: 1 000790208.pdf: 3676280 bytes, checksum: dafede75e9a0efb9c14bb464917e791b (MD5) / A produção de anticorpos monoclonais (mAbs) é de extrema importância na área médica, sendo considerada a grande inovação da indústria biotecnológica. O método descrito por Köhler e Milstein exige a seleção celular por vias bioquímicas através do meio HAT (meio com hipoxantina, aminopterina e timidina). Com o crescente emprego da luz na área médica este trabalho buscou avaliar o emprego do LED (abreviação de Light Emitting Diode) com comprimento de onda de 475nm na seleção das células envolvidas na produção de anticorpos monoclonais com vistas a oferecer uma nova opção na seleção de hibridomas. Culturas celulares de Mieloma Murino (NS1) e MRSA 3-75 e 4-27 em meio completo 10% SFB foram segregadas em seis grupos para cada tipo celular (12 amostras), sendo: G1: controle (não irradiado); G2: 1 J/cm2; G3: 3 J/cm2; G4: 5 J/cm2; G5: 10 J/cm2; G6: 20 J/cm2. Com vistas a determinar o comportamento das células frente ao efeito da luz, foram avaliadas a taxas de viabilidades das células por Citometria de fluxo e MTT (3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide), perfil secretor dos hibridomas por ELISA e nanodrop e taxa crescimento celular pela coloração de Azul de Tripan. Os resultados mostraram que houve bioinibição de NS1 e MRSA 3-75 e 4-27 em doses superiores a 5 J/cm2 promoveram aumento da morte por necrose e apoptose tardia com supressão da produção de anticorpos (hibridomas) em todos os grupos experimentais. Os Hibridomas MRSA 4-27 apresentaram bioestimulação quanto a produção de anticorpos em 31% na dose de 1 J/cm2 porém, o MRSA 3-75 não apresentou alteração no perfil secretor. O LED no comprimento de onda de 475nm não promoveu fotoseleção de mielomas e hibridomas após exposição à luz. Mas, bioestimulou o crescimento celular (NS1) e promoveu aumento da secreção de imunoglobulinas (MRSA 4-27), principal interesse dos laboratórios de bioengenharia que utilizam esta tecnologia / The production of monoclonal antibodies (mAbs) for medicine is highly important, being considered the greatest innovation of the biotechnologic industry over the years. The method described by Köhler e Milstein demands cellular selection through biochemistry ways using HAT (culture medium with hypoxanthine, aminopterin and tymidhine). By the increasing use of lights in the medical areas, this paper searches to evaluate the application of LED (Light Emitting Diode) - wave length of 475nm - in the selection of cells involved on monoclonal antibodies production, in order to offer a new option for hybridoma selection. Cell culture of Murine Myeloma (NS1) and MRSA 3-75 and 4-27 in complete culture medium with 10% of fetal bovine serum (FBS) were separated in six groups for each cellular type (12 samples), being: G1: control group (not irradiated), G2: 1 J/cm2; G3: 3 J/cm2; G4: 5 J/cm2; G5: 10 J/cm2; G6: 20 J/cm2. To determine the behavior of cells, the following tests were made: viability tests by Flow Cytometry and MTT (3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide), ELISA and Emission Spectrometry to check hydridomas’ secretory profile and Tripan blue stain to determine cellular growth rate. The results show that there were bioinstimualtion of NS1 and MRSA 3-75 and 4-27 in doses above of 5 J/cm2, which promoted the increase of death by necrosis and late apoptosis with the reduction of monoclonal antibodies production (hybridoma) in all experimental groups. The MRSA 4-27 hybridomas presented biostimulation as for the anitbodies production in 31% at the dose of 1 J/cm2, although the MRSA 3-75 didn’t present any alteration of secretory profile. The LED with wave length of 475nm didn’t promoted photoselection of hybridomas and myelomas after the exposure to light. However, it biostimulated the cellular growth (NS1) and the increased the secretion of immunoglobulins (MRSA 4-27), which is the main interest of ...

Orientador: Elenice Deffune / Banca: Marjorie de Assis Golim / Banca: Natalia Mayumi Inada / Resumo: A produção de anticorpos monoclonais (mAbs) é de extrema importância na área médica, sendo considerada a grande inovação da indústria biotecnológica. O método descrito por Köhler e Milstein exige a seleção celular por vias bioquímicas através do meio HAT (meio com hipoxantina, aminopterina e timidina). Com o crescente emprego da luz na área médica este trabalho buscou avaliar o emprego do LED (abreviação de Light Emitting Diode) com comprimento de onda de 475nm na seleção das células envolvidas na produção de anticorpos monoclonais com vistas a oferecer uma nova opção na seleção de hibridomas. Culturas celulares de Mieloma Murino (NS1) e MRSA 3-75 e 4-27 em meio completo 10% SFB foram segregadas em seis grupos para cada tipo celular (12 amostras), sendo: G1: controle (não irradiado); G2: 1 J/cm2; G3: 3 J/cm2; G4: 5 J/cm2; G5: 10 J/cm2; G6: 20 J/cm2. Com vistas a determinar o comportamento das células frente ao efeito da luz, foram avaliadas a taxas de viabilidades das células por Citometria de fluxo e MTT (3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide), perfil secretor dos hibridomas por ELISA e nanodrop e taxa crescimento celular pela coloração de Azul de Tripan. Os resultados mostraram que houve bioinibição de NS1 e MRSA 3-75 e 4-27 em doses superiores a 5 J/cm2 promoveram aumento da morte por necrose e apoptose tardia com supressão da produção de anticorpos (hibridomas) em todos os grupos experimentais. Os Hibridomas MRSA 4-27 apresentaram bioestimulação quanto a produção de anticorpos em 31% na dose de 1 J/cm2 porém, o MRSA 3-75 não apresentou alteração no perfil secretor. O LED no comprimento de onda de 475nm não promoveu fotoseleção de mielomas e hibridomas após exposição à luz. Mas, bioestimulou o crescimento celular (NS1) e promoveu aumento da secreção de imunoglobulinas (MRSA 4-27), principal interesse dos laboratórios de bioengenharia que utilizam esta tecnologia / Abstract: The production of monoclonal antibodies (mAbs) for medicine is highly important, being considered the greatest innovation of the biotechnologic industry over the years. The method described by Köhler e Milstein demands cellular selection through biochemistry ways using HAT (culture medium with hypoxanthine, aminopterin and tymidhine). By the increasing use of lights in the medical areas, this paper searches to evaluate the application of LED (Light Emitting Diode) - wave length of 475nm - in the selection of cells involved on monoclonal antibodies production, in order to offer a new option for hybridoma selection. Cell culture of Murine Myeloma (NS1) and MRSA 3-75 and 4-27 in complete culture medium with 10% of fetal bovine serum (FBS) were separated in six groups for each cellular type (12 samples), being: G1: control group (not irradiated), G2: 1 J/cm2; G3: 3 J/cm2; G4: 5 J/cm2; G5: 10 J/cm2; G6: 20 J/cm2. To determine the behavior of cells, the following tests were made: viability tests by Flow Cytometry and MTT (3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide), ELISA and Emission Spectrometry to check hydridomas' secretory profile and Tripan blue stain to determine cellular growth rate. The results show that there were bioinstimualtion of NS1 and MRSA 3-75 and 4-27 in doses above of 5 J/cm2, which promoted the increase of death by necrosis and late apoptosis with the reduction of monoclonal antibodies production (hybridoma) in all experimental groups. The MRSA 4-27 hybridomas presented biostimulation as for the anitbodies production in 31% at the dose of 1 J/cm2, although the MRSA 3-75 didn't present any alteration of secretory profile. The LED with wave length of 475nm didn't promoted photoselection of hybridomas and myelomas after the exposure to light. However, it biostimulated the cellular growth (NS1) and the increased the secretion of immunoglobulins (MRSA 4-27), which is the main interest of ... / Mestre

Photosynthetic organisms exhibit a variety of responses to changes in light intensity, including differential biosynthesis of chlorophyll-protein complexes. Cultures of Rhodobacter capsulatus grown anaerobically with a low intensity of light (2 W/m²) contained about four times as much B800-850 light harvesting complex as cells grown under high light intensity (140 W/m²). The mRNA transcripts encoding B800-850 beta and alpha peptides were analyzed by Northern blot, S1 nuclease protection and capping with guanylyl transferase. It was found that the steady-state levels of B800-850 mRNAs in high light-grown cultures was about four times as great as in cells grown under low light intensity. Therefore the lesser amounts of mature B800-850 peptide gene products found in cells grown with high light intensity were the result of a posttranscriptional regulatory process. It was also found that there were two polycistronic messages encoding the B800-850 peptides. These messages shared a common 3' terminus but differed in their 5' end segments as a result of transcription initiation at two discrete sites. Moreover the half life of B800-850 mRNAs was about 10 minutes in cells grown with high light and approximately 19 minutes in low light-grown cultures. Transcriptional and translational fusions were constructed between the B800-850 transcription initiation region (from this point on referred to as the puc transcription initiation region; see Fig. 1) and the Escherichia coli lacZ gene. From these studies it was concluded that the rates of transcription initiation of the puc (B800-850) genes was higher in cells grown with high light illumination than in low light-grown cultures, and that the relative amount of B800-850 complexes under these conditions was controlled by a translational or a posttranslational mechanism. The translational and transcriptional fusions were also used for examination of oxygen regulated expression of the puc genes. / Science, Faculty of / Microbiology and Immunology, Department of / Graduate

The marine cyanobacterium Synechococcus WH7803 adapts to changes in light intensity by changing its photosynthetic physiology. This work is a study o f the rate o f photoadaptation of Synechococcus WH7803 in laboratory cultures. Cultures were shifted from constant 8 µEm-2s-1 light to constant 80 µEm-2s-1 light, from constant 80 µEm-2s-1 light to 8 µEm-2s-1 light and from different light regimes to a single fluctuating light regime. The response of high iron cultures grown in modified aquil culture medium at 5*10-6M Fe was compared with the response of low iron cultures grown in modified aquil medium at 1*10-6M Fe. Cultures were assayed every 2 days for at least 10 days, assaying cell population density by fluorescence microscopy, chlorophyll a by spectrophotometry of acetone extracts, total protein by the bicinchoninic acid method, and photosynthesis vs. irradiance (P vs. I) response by H14CO3 uptake at 10 light intensities. Iron nutrition did not strongly affect the rate of photoadaptation as determined from the slopes of P vs. I curves as light approaches zero (the parameter called alpha). The rate of chlorophyll a synthesis was the parameter most strongly affected by iron nutrition, slowing in restricted iron medium. Based on alpha per cell, the adaptation time to the shift from constant 8 µEm-2s -1 light to constant 80 µEm-2s -1 light was less than 2 days. Based on other culture parameters the time to complete adaptation may be closer to 8 days. Based on alpha per cell, the adaptation time to the shift from constant 80 µEm-2s -1 light to constant 8 µEm-2s -1 light was on the order of 2 days. Based on other culture parameters the time to complete adaptation may exceed 10 days.

This study was designed to determine the effect of environmental lighting on growth, reproduction and behavior in turkeys. During the growth phase a Large White and a Medium White line of turkeys were reared on an intermittent (2L:2D) or a diurnal (12L:l2D) light regimens under white, red (650 nm) or blue (450 nm) light environments. The turkeys grew faster under blue light than under red or white light up to 16 weeks of age. However, by 24 weeks of age, the rates of gain were significantly greater under the white and red lights. Growth rates were significantly greater under the intermittent regimen as compared to the diurnal regimen for both lines and sexes. The greatest acceleration in growth rate was observed from 4 to 10 weeks of age with this advantage still evident at 24 weeks of age. There were no significant differences in feed efficiency due to regimen or color. Early mortality was highest under blue light but late mortality was greater under red and white light. Mortality was higher for the LW than MW birds. Live grades were unaffected by light regimen or color but feather condition was poorest for birds reared under white diurnal regimen. The light color and regimen had no significant effect on the histological and physiological parameters measured. However, measurements of sexual development tended to be lower in both sexes for birds reared under blue light. Turkeys growing under the blue light regimens were the most placid while those reared under the white diurnal regimen were the most nervous. In the reproductive phase, medium white turkeys from each growth phase regimen and color combination were placed into white, red and blue light pens. Mating behavior measures were higher under red and white light than under blue light. In addition, rearing of turkeys under blue lights appeared to reduce sexual behavior in Experiment 2. For most mating behavior measures, the optimum light color combination appeared to be the white growth-white reproductive light program. While all mating behavior measures were continually lower for turkeys reared under intermittent light than those reared under a diurnal regimen, these differences were not significantly different. Turkeys exhibited two types of agonistic behavior. Fights between toms and hens occurred regularly in the blue reproductive light pens and rarely in the others. The majority of the fights occurred among hens and toms reared under red light. Toms from blue growth phase pens and subsequently placed in the red reproductive light environments, exhibited a super-aggressive behavior towards any human entering those pens. Egg production and semen volume measures were significantly greater for turkeys in the red and white reproductive pens than for those under the blue light conditions. The hens in the red and white growth pens came into egg production prematurely at 27 weeks of age when maintained on an intermittent light regimen during the growth phase. / Ph. D.

The role of light and temperature on flowering of South African Watsonia species were evaluated to assess the potential for this genus as a commercial flower crop. Species were selected that represent different climatic regions of South Africa, with the aim of understanding how ecologically distinct species perform under cultivation. The four selected species were W. borbonica and W. tabularis (winter-rainfall area), W. angusta (shared rainfall) and W. pillansii (summer-rainfall area). In order to establish the optimum temperature required for flowering, plants were exposed for 12 weeks to three temperature regimes (12/7 °C, 21/15 °C and 29/21 °C) after attaining their first and/or second leaves. A temperature shift of 12/7 °C was used to assess if the plants had a vemalisation requirement. Controls were maintained under 25 % shade under natural conditions, with an average temperature of 24/7 °C. An elevated temperature of 29/21 °C was detrimental to plant growth. Moderate temperatures of 21/15 °C significantly (P<0.001) increased the height and the number of leaves produced per plant relative to the 12/7 °C treatment. These temperatures significantly (P<0.001) increased the total number of flowers produced per plant compared to low temperatures. However, flowering percentage and quality of flowers were reduced. A low temperature regime of 12/7 °C was efficient in satisfying vernalisation requirements and inducing flowering in four selected species. However, the total number of leaves produced per plant was signifcantly reduced. The summer-rainfall species, W pillansii, displayed a qualitative response to vernalisation, as no flowering was observed in non-vernalised plants. Two winter-rainfall species, W borbonica and W. tabularis, demonstrated a quantitative response to vernalisation. These species flowered at non-vernalising temperatures. W angusta behaved like the winter-rainfall species in terms of flowering. Overall, a vernalisaton treatment marginally reduced days to flower while flowering percentage was increased compared to other temperature regimes. However, there was no increase in the total number of flowers produced per plant. Low temperatures were not only effective for flower induction, but also for releasing corm dormancy, thus synchronising growth. Storing corms at either 4 or 10 QC resulted in 100 % sprouting within 4-6 weeks. The role of daylength in flowering of Watsonia plants was established by subjecting plants to long days (LO) of 16 h light and 8 h dark and to short days (SO) of 8 h light and 16 h dark. The number of leaves and flowering were significantly (P<0.01) promoted under the LO regime. However, there was strong temperature and daylength interaction in terms of flowering potential, as at low temperatures flowering was induced irrespective of daylength. In W. pillansii, flowering was obtained under both regimes (LO and SO) applied at the second leaf stage. Flowering in W. borbonica and W. tabularis was only observed under the LO regime at the second leaf stage. In both species, flowering was also obtained in SD-treated plants, provided treatment occurred after the formation of the third leaf. However, the total number and quality of flowers were reduced. To examine the effect of light intensity on flowering, plants at different developmental stages (first and/or second or beyond the third leaf stage) were exposed to photosynthetically active radiation (PAR) of 150 jJmol m-2s-1 or 39.5 jJmol m-2s-1 for 7 weeks. Exposure to low light intensity at either developmental stage compromised leaf quality. No flowering was observed following low light intensity treatment during the first to third leaf stages, even though plants were exposed to low temperature and LO regimes, both of which promoted flowering. Observation of the shoot apical meristem revealed that the second leaf stage was critical as the anatomical transition to flowering occurred at this level. When beyond the third leaf stage, low light intensity did not prevent flowering. However, the number of flowers produced per plant was reduced compared to plants maintained at 150 jJmol m-2s-1. Thus, light intensity played a role in both plant morphogenesis and flowering. LDs were effective in promoting vegetative growth whereas high light intensity and low temperature regimes played pivotal roles in flower induction. This makes them useful horticulture tools to produce desirable Watsonia plants for commercialisation. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.