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1
Compton, Robert I. "Population fragmentation and white sucker introduction affect populations of bluehead suckers, flannelmouth suckers, and roundtail chubs in a headwater stream system, Wyoming." Laramie, Wyo. : University of Wyoming, 2007. http://proquest.umi.com/pqdweb?did=1404346401&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
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Tshireletso, Koketso. "Simulated Browsing Impacts On Aspen Suckers' Density, Growth, and Nutritional Responses." DigitalCommons@USU, 2008. https://digitalcommons.usu.edu/etd/133.
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Heavy and repeated ungulate browsing on reproductive suckers has limited trembling aspen (Populus tremuloides Michx.) regeneration on many Western landscapes. However, little is known about the specific effects of season and intensity of browsing. My objectives were to determine the effects of season and intensity of clipping (simulated browsing) on suckers’ (1) density and growth characteristics, and (2) nutritional quality and quantity.
Three randomly selected stands were clear-felled in mid-July, 2005, and fenced. Simulated browsing treatments of 0%, 20%, 40%, and 60% removal of current year’s growth were randomly applied in early, mid-, and late summers of 2006 and 2007. Sucker density, height, leader length, twig numbers, bud numbers, basal area, and biomass harvested were monitored in each quadrat. Harvested material was analyzed for crude protein and in vitro true dry matter digestibility.
Early summer clipped suckers suffered no winter mortality compared to mortalities of 41% and 42% for mid- and late summer clipped suckers, respectively. However, even at the highest mortality, there were still ample numbers of suckers for stand regeneration. Sucker height was restricted by all early summer treatments. Clipping at 20% and 40% in mid- and late summer, respectively, did not reduce sucker height, but suckers clipped 60% were ≤ 40 cm shorter than controls. Twig and bud density both declined with increasing intensity of clipping. By the study’s end, basal area of early summer clipped suckers was higher than for those clipped in late summer.
Crude protein of clipped biomass decreased with season’s advance and clipping intensity. Levels ranged from 12.8% to 22.9% and 10.6% to 16.5% in 2006 and 2007, respectively. Digestibility ranged from 80.1% to 93.4% and 75.2% to 90.7% in 2006 and 2007, respectively. Biomass (260 vs. 181 kg/ha) and total digestible dry matter (197 vs. 142 kg/ha) harvested were higher in mid-summer clipped plots in 2007 than in 2006, respectively. Apart from early summer, total nitrogen harvested was not affected differently by season of clipping.
Clear-felling programs that allow browsing of ≤ 40% in mid- and late summer would ensure sustained aspen stand density and growth.
(184 pages)
3
Thieme, Michele Lorraine 1971. "Movement and recruitment of flannelmouth suckers in the Paria and Colorado rivers, Arizona." Thesis, The University of Arizona, 1997. http://hdl.handle.net/10150/278647.
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Sonic-tagged flannelmouth suckers made long distance and local movements; 12.5% of fish moved ≥ 98 km downstream and 40% stayed within Glen Canyon. Motivation for long distance movements could be spawning or food related. A controlled flood of 1,274 m³/sec did not displace flannelmouth suckers downstream or interrupt spawning. The majority (62%) of fish moved into the impounded mouth of the Paria River. Spawning occurred as evidenced by capture of adults over spawning areas and collection of young-of-year (YOY) in spring and summer. From May-September 1996, YOY flannel mouth suckers were captured in the impounded mouth of the Paria River. Successful rearing of YOY fish was attributed to the presence of a warm, slackwater area in the mouth. Formation of this area is dependent upon antecedent Colorado and Paria river flows and their effect on sediment deposition in the mouth of the Paria River.
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Bonilla, Victoria. "The Succubus and the Suckers: the Soul-Siphoning Leeches in the Stories of Modernist Text." ScholarWorks@UNO, 2014. http://scholarworks.uno.edu/td/1851.
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This paper explores the various relationships found in John Steinbeck's "Of Mice and Men," Tennessee Williams's "A Streetcar Named Desire," Franz Kafka's "The Metamorphosis," and F. Scott Fitzgerald's "Tender is the Night." The exploration of each demonstrates the common theme of parasitic relations and the toll this dynamic takes on the persons involved.
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Delorme, Peter D. "The effects of toxaphene, chlordane and 2,3,4,7,8-pentachlorodibenzofuran on lake trout and white sucker in an ecosystem experiment and the distribution and effects of 2,3,4,7,8-pentachlorodibenzofuran on white suckers and broodstock rainbow trout in laboratory experiments." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1995. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq23595.pdf.
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Marcogliese, Lucian A. "Factors affecting length and age at the first maturity of white suckers, Catostomus commersoni, in lake trout lakes in the Haliburton Highlands, Ontario." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1996. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq21674.pdf.
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Albarracin, Maria Teresa. "Bottom-up and top-down effects on insects herbivores along a natural salinity gradient in a florida salt marsh." [Tampa, Fla.] : University of South Florida, 2005. http://purl.fcla.edu/fcla/etd/SFE0001002.
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Mitchell, Alison. "Habitat assessment of the invasive white sucker (Catostomus commersoni) and the native bluehead sucker (Catostomus discobolus) at multiple spatial scales." Connect to online resource, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1446109.
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Cole, David. "Ecomorphological and Genetic Investigations into the Utah Lake, UT Sucker Complex with Comparisons to the Jackson Lake, WY Sucker Complex." DigitalCommons@USU, 2014. https://digitalcommons.usu.edu/etd/2122.
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Ecomorphological specialization within Catostomidae in several large western North American lakes has produced populations including typical benthic suckers (Catostomus) and lakesuckers (Chasmistes), mid-water planktivores, with a continuum of morphologies existing between them. All extant lakesuckers are endangered, and population declines have been attributed in part to hybridization with sympatric Catostomus spp. Chapter 2 describes assessment for concordance of morphological and genetic variation in suckers in Utah Lake, Utah (June sucker, Chasmistes liorus; Utah sucker, Catostomus ardens; and suckers of intermediate morphology) by comparing a morphological analysis with amplified fragment length polymorphism and microsatellite analyses. Suckers were differentiated using characters associated with presumed feeding strategies: zooplanktivory (June sucker) and benthivory (Utah sucker). No molecular evidence was found for deep genetic divergence between morphs or for hybridization among ancient lineages. Slight population structuring accompanied substantial morphological variation. Chapter 3 describes the investigation of distribution and movement, spawning behavior, and diet of suckers in Utah Lake and their growth at different densities in a laboratory experiment. Acoustic / radio telemetry revealed little difference in movement and distribution of June sucker and Utah sucker or in timing of spawning runs. Stable isotopes analysis revealed that Utah sucker were enriched in 13C relative to June sucker as presumed diets would predict. Intermediate morphs were intermediate for δ13C and δ15N. Neither species nor density was a significant predictor of growth rate of June sucker or Utah sucker reared at different conspecific densities. Chapter 4 examines morphology, genetics, and diet of the sucker population inJackson Lake, Wyoming, once home of the extinct Snake River sucker, Chasmistes muriei, a lakesucker known from a single specimen. Currently, suckers in Jackson Lake are identified as Utah sucker; however, recently sampled individuals resemble lakesucker. No molecular evidence was found for deep genetic divergence between lakesucker and benthic morphs or for hybridization among ancient lineages. The benthic morph was significantly enriched in 13C relative to the lakesucker morph, consistent with presumed diets. Morphologically, the lone Snake River sucker holotype specimen grouped strongly with extant lakesucker morphs, suggesting that the status of the Snake River sucker be updated accordingly.
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Tshireletso, Koketso. "Simulated Browsing Impacts on Aspen Sucker's Survival and Growth." DigitalCommons@USU, 2005. https://digitalcommons.usu.edu/etd/6430.
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Western forests dominated by aspen (Populus tremuloides Michx.) are highly regarded by most resource managers for their ability to provide a variety of benefits (Bartos and Mueggler 1982, Mueggler 1988). They noted aspen to be beneficial for production of livestock forage, wildlife habitat, and scenic beauty, and they are a potentially valuable source of wood products. However, in the West, communities are concerned about the dwindling acreage of aspen. The decline of aspen has been partly attributed to excessive ungulate browsing (Smith et al. 1972, Collins and Urness 1983, Bartos and Campbell 1998). Long-term grazing exclosures have also revealed that browsing by native and domestic ungulates hindered aspen regeneration throughout south-central Utah, including changes in understory species composition ( e.g. Kay and Bartos 2000). However, though ungulate browsing is an established cause of poor success in aspen regeneration, beyond that fact, very little is known about the particulars of the response, especially how it is affected by time and intensity of browsing.
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NOGUEIRA, LOUISE DA SILVA DOURADO. "SUCKER`S LIFE: THE WORKERS EXIT OF LUMIÈRE`S." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2005. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=7667@1.
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FUNDAÇÃO DE APOIO À PESQUISA DO ESTADO DO RIO DE JANEIROVida de otário: A saída dos operários da fábrica de Lumière se constitui numa análise sobre as representações do trabalho no cinema brasileiro contemporâneo, à luz das mudanças ocorridas na esfera da cultura e da economia mundial ao longo da década de 90. As obras exibidas no início do século XXI são colocadas em diálogo com filmes nacionais dos anos 60, 70 e 80 a fim de verificar como o declínio das utopias, que inspiraram o projeto moderno, afetou o lugar ocupado pela figura do operário na fábrica de Lumière.
Vida de otário: A saída dos operários da fábrica de Lumière consists of the analysis of representations of labor within contemporary Brazilian cinema, considering the changes in the sphere of global culture and economy during the 1990s. Movies released in the beginning of the present century are contrasted with national films from the 1960s, 70s and 80s in order to verify how the fading of the idea of utopia which inspired the modern project has affected the place occupied by the figure of the laborer in Lumière`s factory.
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Ward, David Lance. "Effects of Reduced Water Temperature On Swimming Performance and Predation Vulnerability of Age-0 Flannelmouth Sucker (Catostomus latipinnis)." Thesis, The University of Arizona, 2001. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_2001_181_sip1_w.pdf&type=application/pdf.
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Laitnen, Nina Johanna. "The Phylogeography of the Mountain Sucker [Catostomus (Pantosteus) platyrhynchus]." BYU ScholarsArchive, 2012. https://scholarsarchive.byu.edu/etd/3148.
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Pantosteus, a subgenus of Catostomus, includes the mountain sucker (Catostomus playthyrnchus), whose speculated older origins in the Miocene/Pliocene can provide insight into the ancient geographical events of western North America. We believe that major geologic events influencing the diversification of mountain suckers include the rise of the Colorado Plateau, the connections between the ancient Snake River system and the Lahontan system and subsequently the connection of the Snake River system to the Columbia Basin, dispersal of mountain suckers across the continental divide, as well as the Pleistocene Bonneville flood. If this is true, we should see evidence of geologic separation and timing through studying the phylogenetics of the mountain sucker. In order to clarify relationships of the mountain sucker with respect to other Pantosteus species, we examined cytochrome b (cyt b) sequences for 144 mountain suckers, 24 other Pantosteus species, and ten outgroup species. Phylogenetic relationships among haplotypes were constructed based on maximum likelihood and Bayesian criterion. In an effort to provide better resolution at some nodes, we also sequenced additional mitochondrial genes (ND1, ND2, ATPase, ND4L, ND4, ND5, ND6, and cyt b) for a subset of 44 individuals taken from the major clades obtained from the cyt b phylogentic analyses. Trees from this data set were also constructed under maximum likelihood and Bayesian criterion. All phylogenetic analysis revealed that mountain sucker are paraphyletic, with two major clades of mountain suckers separated by other members of the subgenus Pantosteus. One clade included two sub-clades, one from the upper Snake River drainage/northern Bonneville/Green River drainage Basins and the other from the southern Bonneville Basin. The other major clade included sub-clades from the Lahontan Basin, Columbia River Basin, and Upper Missouri River Basin. Molecular clock analysis revealed that Pantosteus likely split from Catostomus during the Miocene and that major speciation events within Pantosteus occurred during the Pliocene and Pleistocene. Genetic structuring and gene flow estimates for mountain sucker populations, with groupings based on major drainage basins, were calculated with AMOVA and Fst estimates in Arlequin and revealed that most of the genetic structuring was explained by variation among drainage basins with limited gene flow occurring between drainage basins. Based on this study, the role of the Colorado Plateau's geologic history in the evolution of the mountain sucker remains unclear. However, all other geologic events as discussed in this study seem to have played a significant role in the evolution of the mountain sucker.
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Silva, Thaís Cristina Ribeiro da. "Cellular and molecular mechanisms underlying root sucker formation in Arabidopsis lyrata." Universidade Federal de Viçosa, 2017. http://www.locus.ufv.br/handle/123456789/16347.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico
A organogênese de brotos a partir de raízes (rootsuckers) permite a propagação vegetativa daArabidopsis lyrata, o parente mais próximo daArabidopsis thaliana. Utilizando um sistema in vitro, o presente estudo objetivou compreender melhor a propagação vegetativa nessa espécie modelo A. lyrata, no que se refere ao desenvolvimento morfológico de suckers, à capacidade de propagação vegetativa em diferentes condições de crescimento in vitro e à identificação de genes potencialmente envolvidos na formação do meristema apical dos brotos.O surgimentodos suckers ocorreu após 30 dias, mais freqüentemente na região axilar das raízes laterais. Os cortes transversais das raízes mostraram uma estrutura primária típica diarca e após cerca de 25 dias, pode-se observar o crescimento secundário da raiz, como indicado pela formação do câmbio. Conclui-se que a emergência do sucker assemelha-se à iniciação das raízes laterais a partir do periciclo, tecido que dá origem ao câmbio vascular durante o crescimento secundário. Em relação às condições de crescimento in vitro, a força total no meio MS induziu o maior número de suckers por planta, seguido por alta concentração de sacarose (3%).Exposição à luz e privação de sacarose não são estritamente necessários para a formação de suckers. Nossos dados também revelaram que a auxina promove a formação dos brotos. Máximas de auxina vascular são necessários para desencadear a iniciação da raiz lateral, sugerindo que a formação de suckers promovida por auxina ocorre provavelmente por mecanismos semelhantes. A avaliação de diferentes genes relacionados a meristema apical, demonstram que o gene STM pode ser um marcador para distinguir as células responsáveis pela formação de suckers. Arabidopsis lyrata provou ser um excelente modelo para estudos de organogênese em raíz e posteriores estudos usando esse sistema de reproduçãopara detectar marcadores epigenéticos através das várias gerações de propagação clonal.
Shoot organogenesis from roots (root suckers) allows vegetative propagation of Arabidopsis lyrata, the closest relative of Arabidopsis thaliana, in addition to sexual propagation and is an important trait associated with the root system. Using an in vitro system, we aimed to better understand the vegetative propagation in the model species A. lyrata, in what regards the morphological development of root suckers, the ability of vegetative propagation in different in vitro growth conditions, and identifying genes potentially involved in the formation of the new shoot apical meristem.Root sucker appearanceoccurred after30 days,most frequently in the axils of lateral roots. Root cross-sections showed a typical diarch primary structure and after 25 days, secondary root growth could be observed, as indicated by formation of the cambium. According to our data,root sucker emergence resembles the initiation of lateral roots from the pericycle, the tissue that gives rise to the vascular cambium during secondary growth. Regarding the in vitro growth conditions, full strength of MS induced the highest number of root suckers per plant, followed 3% of sucrose. However, light exposure and sucrose deprivation are not strictly required for sucker formation. Our data also revealed that auxin promotes root suckering. Vascular auxin response maxima are required to trigger lateral root initiation, suggesting that auxin- promoted sucker formation likely occurs by similar mechanisms. The evaluation of different shoot apical meristem related genes, suggests that the STM gene can be a potential marker to identify cells responsible in driving sucker formation. Arabidopsis lyrata proved to be an excellent model for further studies using root suckers, for example to study epigenetic marks throughout generations of clonal propagation.
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Buck, Chelsea. "Characterization and Functionalization of Suckerin-12 Protein Hydrogels." University of Dayton / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1542729200115677.
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Weiss, Steven Joseph 1958. "Spawning, movement and population structure of flannelmouth sucker in the Paria River." Thesis, The University of Arizona, 1993. http://hdl.handle.net/10150/278382.
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Spawning flannelmouth sucker, Catostomus latipinnis, in the Paria River averaged 478 mm (n = 246) total length (TL). This was 53 mm longer (p < 0.001) than the mean length of spawning fish taken from this same location in 1981 (425 mm, TL, n = 286). Sub adult flannelmouth were common in the Paria in 1981 but no post-larval fish < 379 mm, TL were caught in 1992 or 1993. There is no evidence that juvenile flannelmouth have reared in the Paria River/Glen Canyon Area in the last 12 years. However, some adult fish appear to enter the population from downstream locations. In 1992 and 1993, spawning occurred throughout the lower 10 kilometers of the Paria. Young-of-year were seen in 1992 but could not be found shortly after hatching. No young-of-year were seen in 1993. Growth of adult sized fish is very slow. Based on extrapolations from recaptures, longevity may approach 30 years. Recaptures from fish marked in other studies were originally tagged as far as 229 km downstream from the mouth of the Paria.
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Makatini, Gugulethu Joy. "The role of sucker wounds as portals for grapevine trunk pathogen infections." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86599.
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Thesis (MScAgric)--Stellenbosch University, 2014.ENGLISH ABSTRACT: Grapevine trunk diseases are responsible for reduced wine and table grape production world-wide. Trunk disease infections are caused by xylem-inhabiting pathogens which include species of Botryosphaeriaceae, Diatrypaceae, Hymenochaetales and Diaporthales, as well as Phaeomoniella chlamydospora and Phaeoacremonium spp. Winter pruning wounds are regarded as the main infection-sites for trunk disease pathogens. However, the role of sucker wounds as portals of trunk disease infections has been minimally investigated. Knowledge of the potential role of grapevine trunk pathogen infections that occur through sucker wounds is important for better wound protection strategies. The aim of this study was to determine the role of grapevine sucker wounds as portals of entry for trunk disease pathogens and to assess the use of Trichoderma spp. for sucker wound protection. The susceptibility of sucker wounds to different trunk disease pathogens was assessed from natural as well as artificial infections. In addition the duration of sucker wound susceptibility in the field was also ascertained. Sucker wounds were sampled from three wine and two table grape vineyards during 2011 and 2012 in the Western Cape province of South Africa. Thereafter, fungal isolations were made from 161 sucker wounds and the cultures were identified based on cultural and morphological characteristics as well as the internal transcribed spacer regions and 5.8S ribosomal RNA gene. Sixty-two percent of the wounds were naturally infected by at least one of the trunk pathogens. Phomopsis (Po.) viticola (46%; 18%), Diplodia (D.) seriata (30%; 9%) and Phaeomoniella (Ph.) chlamydospora (27%; 5%) were the most predominant trunk disease pathogens isolated from sucker wounds of field wine and table grape cultivars, respectively. Lower incidences of Phaeoacremonium aleophilum (18%), Eutypella sp. (3%), Cryptovalsa ampelina (2%), Diplodia sp. (1%) and Neofusicoccum australe (1%) were obtained, however, only from wine grapes. Sucker wounds on 1-year-old potted grapevine plants of Chardonnay cultivar were inoculated with spore suspensions of Eutypa lata, N. parvum, Pa. aleophilum, Ph. chlamydospora and Po. viticola in the glasshouse. After 4 months all the inoculated pathogens could be re-isolated at the following incidences: N. parvum (85%), Ph. chlamydospora (75%), Po. viticola (65%), Pa. aleophilum (55%) and E. lata (45%). Sucker wound susceptibility was further ascertained under field conditions on 12-year-old Cabernet Sauvignon vines by artificial inoculation of the same pathogen species. After 5 months three pathogens could be re-isolated at the following incidences: Po. viticola (65%), N. parvum (32.5%) and Ph. chlamydospora (7.5%). The duration of susceptibility of field sucker wounds to Ph. chlamydospora was assessed for a period of 4 weeks. The wounds remained susceptible for 4 weeks with a decline in susceptibility after one week. This study showed that sucker wounds are susceptible to the major trunk disease pathogens and thus could play an important role in grapevine trunk disease epidemiology. In the second part of this thesis a possible management strategy to prevent infections of sucker wounds was investigated. The use of Trichoderma (T.) harzianum against two trunk pathogens on sucker wounds was tested in the field. Additionally the sensitivity of T. harzianum and T. atroviride was tested in vitro against 16 fungicides that are used to control powdery mildew, downy mildew, Botrytis rot and Phomopsis cane and leaf spot. In October 2012, sucker wounds were made on 1-year-old wood of Cabernet Sauvignon and spray-treated with Eco-77® immediately after desuckering, and then inoculated with spore suspensions of either Ph. chlamydospora or Po. viticola after 24 hours. After 5 months, isolations were made from the sucker wounds to evaluate the efficacy of the Trichoderma treatment. Trichoderma harzianum reduced the incidence of Ph. chlamydospora by 66.65%. Although the incidence of Po. viticola was reduced by 15.37%, it was not significantly different from the control treatment. The inhibition of mycelial growth and conidial germination of T. harzianum and T. atroviride were screened against 16 fungicides. The fungicides were applied at 0, 0.25, 0.5, 1 and 2 times the recommended dosages. Systemic fungicides boscalid, metrafenone and trifloxystrobin, as well as contact fungicides quinoxyfen and meptyldinocap were least toxic to Trichoderma spp. isolates. For the conidial germination assay, boscalid, trifloxystrobin, penconazole and metrafenone (systemic) plus quinoxyfen and folpet (contact) were compatible with Trichoderma spp. These fungicides were regarded as being compatible with Trichoderma spp. isolates because they gave mean percentage inhibitions of less than 50% at all the tested dosages. Spiroxamine and pyrimethanil gave the highest mean percentage inhibitions for both mycelial inhibition and conidial germination. The findings of this study showed that T. harzianum can protect sucker wounds against Ph. chlamydospora in the field. Furthermore, some fungicides applied for the control of powdery mildew and Phomopsis cane and leaf spot can be alternatively or simultaneously applied with T. harzianum and T. atroviride, however, this will have to be verified with field trials.
AFRIKAANSE OPSOMMING: Wingerd stamsiektes is wêreldwyd verantwoordelik vir verminderde wyn- en tafeldruif produksie. Stamsiektes word veroorsaak deur patogene wat in die xileem voorkom, insluitend verskeie spesies in die Botryosphaeriaceae, Diatrypaceae, Hymenochaetales en Diaporthales, asook Phaeomoniella chlamydospora en Phaeoacremonium spp. Winter snoeiwonde word beskou as die hoof bron van infeksies vir stamsiekte patogene. Die rol van suierwonde as poorte van infeksie vir stamsiektes is nog nie goed bestudeer nie. Kennis van die potensiële rol van wingerd stamsiekte patogeen infeksies wat deur suierwonde plaasvind is belangrik vir die formulasie van beter wondbeskerming strategieë. Die mikpunt van hierdie studie was om die rol van suierwonde as ingangsportale vir wingerd stamsiekte patogene te bepaal en om die gebruik van Trichoderma spp. vir suierwond beskerming te evalueer. Die vatbaarheid van suierwonde vir verskillende stamsiekte patogene is geëvalueer vanuit natuurlike, sowel as kunsmatige infeksies. Die duur van suierwond vatbaarheid in die veld is ook bepaal. Suierwonde is versamel vanuit drie wyn- en twee tafeldruif wingerde gedurende 2011 en 2012 in die Wes Kaap provinsie van Suid Afrika. Hierna is swam isolasies gemaak vanuit 161 suierwonde en die kulture is geïdentifiseer volgens kultuur en morfologiese kenmerke, sowel as die interne transkribeerde spasieerders en 5.8S ribosomale RNA geen. Twee-en-sestig persent van die wonde was geïnfekteer deur ten minste een van die stamsiekte patogene. Phomopsis (Po.) viticola (46%; 18%), Diplodia (D.) seriata (30%; 9%) en Phaeomoniella (Ph.) chlamydospora (27%; 5%) was die mees algemene stamsiekte patogene wat, respektiewelik, vanuit die wyn- en tafeldruif kultivars verky is. Laer hoeveelhede Phaeoacremonium aleophilum (18%), Eutypella sp. (3%), Cryptovalsa ampelina (2%), Diplodia sp. (1%) en Neofusicoccum australe (1%) is verkry, en slegs vanaf wyndruiwe. Suierwonde op 1-jaar oue Chardonnay wingerdplante in potte is in die glashuis geïnokuleer met spoorsuspensies van Eutypa lata, N. parvum, Pa. aleophilum, Ph. chlamydospora en Po. viticola. Na 4 maande kon al die geïnokuleerde patogene her-isoleer word teen die volgende hoeveelhede: N. parvum (85%), Ph. chlamydospora (75%), Po. viticola (65%), Pa. aleophilum (55%) en E. lata (45%). Suierwond vatbaarheid is verder geëvalueer onder veld kondisies op 12-jaar oue Cabernet Sauvignon plante deur kunsmatige inokulasie van die selfde patogeen spesies. Na 5 maande kon drie patogene her-isoleer word teen die volgende hoeveelhede: Po. viticola (65%), N. parvum (32.5%) en Ph. chlamydospora (7.5%). Die duur van vatbaarheid van suierwonde teen Ph. chlamydospora in die veld is geevalueer oor ‘n periode van 4 weke. Die wonde het vatbaar gebly vir 4 weke met ‘n afname in vatbaarheid na ‘n week. Hierdie studie demonstreer dat suierwonde vatbaar is vir die hoof wingerd stamsiektes en dus ‘n belangrike rol in die epidemiologie van wingerd stamsiektes kan speel. In die tweede deel van hierdie tesis is ‘n moontlike bestuurs-strategie ondersoek om infeksie van suierwonde te verhoed. Die gebruik van Trichoderma (T.) harzianum teen twee stampatogene op suierwonde is getoets in die veld. Verder is die in vitro sensitiwiteit van T. harzianum en T. atroviride getoets teen 16 fungisiedes wat gebruik word in die beheer van poeieragtige meeldou, donsskimmel, Botrytis vrot en Phomopsis streepvlek. Gedurende Oktober 2012 is suierwonde gemaak op 1-jaar oue hout van Cabernet Sauvignon en onmiddelik behandel met Eco-77® na suiering. Wonde is dan geïnokuleer met spoorsuspensies van óf Ph. chlamydospora óf Po. viticola na 24 uur. Na 5 maande is isolasies gemaak vanaf suierwonde om die doeltreffendheid van van die Trichoderma behandeling te evalueer. Trichoderma harzianum het die voorkoms van Ph. chlamydospora met 66.65% verminder. Alhoewel die voorkoms van Po. viticola verminder is met 15.37%, was dit nie ‘n beduidende verskil in vergelyking met die kontrole behandeling nie. Die inhibisie van miselium groei en konidia ontkieming van T. harzianum en T. atroviride is getoets teen 16 fungisiedes. Die fungisiedes is aangewend teen 0, 0.25, 0.5, 1 en 2 keer die aanbevole dosisse. Sistemiese fungisiedes boscalid, metrafenone en trifloxystrobin, sowel as kontak fungisiedes quinoxyfen en meptyldinocap was die minste toksies teen Trichoderma spp. Gedurende die konidia ontkiemingstoets was boscalid, trifloxystrobin, penconazole en metrafenone (sistemies) en quinoxyfen en folpet (kontak) versoenbaar met Trichoderma spp. Die fungisiedes is beskou as bruikbaar met Trichoderma spp. isolate omdat hulle gemiddelde persentasie inhibisies van minder as 50% teen al die getoetste dosisse gelewer het. Spiroxamine en pyrimethanil het die hoogste gemiddelde persentasie inhibisie gelewer vir beide die miselium inhibisie en konidia ontkieming. Die bevindings van hierdie studie het gewys dat T. harzianum suierwonde kan beskerm teen Ph. chlamydospora in die veld. Verder sou sommige fungisiedes wat aangewend word vir die bestuur van poeieragtige meeldou en streepvlek moontlik alternatiewelik of gelyktydig met T. harzianum en T. atroviride aangewend word, alhowel dit met veldproewe bevestig moet word.
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Hoover, Hannah. "From Byronic to Gothic Blood Sucker: Subversion toward a Non-Gendered Identity." Digital Commons @ East Tennessee State University, 2021. https://dc.etsu.edu/etd/3886.
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Analyzing Emily Bronte’s Wuthering Heights and linking trends of the Byronic hero that have merged into a variety of genres reveal that the hero is a mode of subversive gender expression, which has evolved within the Gothic through feminine desire. Delving into Bram Stoker’s Dracula will provide unique insight into the audience’s desires/expressions of gender. Finding the transition point from the monster vampire of Dracula to Stephanie Meyer’s desirous, sparkling boy-next-door in Twilight will track the trajectory of gender and sexual norms through time. From the foundational adaptation of the Byronic hero in Wuthering Heights to the repressed vampiric desire of Dracula, to queer desire/domestication within Anne Rice’s Interview with the Vampire, ending with sparkling vampires of Twilight, we can invite the Byronic hero, which already supports rejection of societal expectations, into a genderless space, becoming a champion of desire absent from the constraints of gender and sexuality conformity.
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Winters, Nathan S. "Schoolgirls with Katanas: Appropriating Japaneseness and the Postmodern Cool in Sucker Punch." Bowling Green State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1335535261.
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Barreto, Filho Manuel de Almeida. "Estimation of average reservoir pressure and completion skin factor of wells that produce using sucker rod pumping /." Full text (PDF) from UMI/Dissertation Abstracts International, 2001. http://wwwlib.umi.com/cr/utexas/fullcit?p3008273.
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Huntley, Selene J. "Longitudinal studies of intramammary infection in suckler ewes." Thesis, University of Warwick, 2013. http://wrap.warwick.ac.uk/57216/.
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Four longitudinal studies were conducted. The first study investigated the longitudinal pattern of udder half somatic cell count (HSCC) and intramammary infection (IMI) in 48 UK suckler ewes over the first 10 weeks of lactation. This was the first study to demonstrate that HSCC of suckler ewes followed a quadratic and cubic relationship with days in lactation over the first 10 weeks of lactation. Udder half somatic cell count was also explained by presence of bacteria. Ewes older than 6 years of age had significantly higher HSCC than younger ewes. The second study investigated the relationships between udder conformation, SCC and lamb weight. Whilst accounting for lamb age and birth weight, significantly lower lamb weight was associated with a ewe SCC of >400,000 cells/ml (-1.7 kg), a traumatic teat lesion (bite, tear or chapping) 2 weeks previously (-1.1 kg), and a ewe body condition score (BCS) of <2.5 before lambing (-1.3kg). Higher HSCCs were observed in ewes with a lower suspended udder, and older ewes in poorer body condition. The findings from this study make an important contribution to the knowledge of the impact of udder health of suckler ewes by demonstrating that udder conformation is associated with IMI and that IMI and teat damage are negatively associated with lamb weight. The third study investigated the effect of dry cow therapy (DCT) on subclinical mastitis in a lowland flock with a low incidence of clinical mastitis by recording HSCC and lamb weights in the following lactation. To the author’s knowledge, there are no published reports of the effect of broad spectrum DCT on subclinical mastitis in suckler ewes in the literature. No significant effect was found between the use of DCT and HSCC or lamb weight in the subsequent lactation. The fourth study was a randomised controlled trial to assess the effect of DCT on clinical mastitis in a suckler flock with a high level of clinical mastitis. Dry cow treatment significantly reduced the incidence of clinical mastitis over one year, with a 70% reduction of clinical mastitis in ewes that received treatment from 6.2% to 1.8%. This was the first field trial to investigate and demonstrate the clinical benefit of the use of a broad spectrum DCT in suckler ewes. These studies have enhanced our knowledge of longitudinal patterns of infection and demonstrated the importance of udder health for optimising production of suckler ewes. Factors to control for when using SCC as a tool to measure intramammary infection were described.
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Dion, René. "Resource partitioning in a spring spawning freshwater fish assemblage dominated by catostomids (Catostomus commersoni, C. catostomus)." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60700.
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For three consecutive years, I monitored the spring stream residency and spawning of five species of fishes using a tributary stream of the Gouin Reservoir (north central Quebec). Timing of spawning of the distantly related species was different whereas the spawning activity of the closely related suckers overlapped in time and space. Intra- and inter-specific egg predation by the two sucker species was observed as well as predation by lake whitefish (Coregonus clupeaformis) on sucker eggs. Synchronisation of the spawning of the suckers may allow them to "swamp" egg predators with drifting eggs. Abundance of spawning fish was affected by water management practices in the reservoir. When water levels were low, fewer fish of all species had access to the stream possibly because of the development of rapids.The courtship behavior of the two sucker species was described and compared in the same period, to determine if behavioral isolating mechanisms which prevented hybridization existed.
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Bottcher, Jared L. "Maintaining Population Persistence in the Face of an Extremely Altered Hydrograph: Implications for Three Sensitive Fishes in a Tributary of the Green River, Utah." DigitalCommons@USU, 2009. https://digitalcommons.usu.edu/etd/496.
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The ability of an organism to disperse to suitable habitats, especially in modified and fragmented systems, determines individual fitness and overall population viability. The bluehead sucker (Catostomus discobolus), flannelmouth sucker (Catostomus latipinnis), and roundtail chub (Gila robusta) are three species native to the upper Colorado River Basin that now occupy only 50% of their historic range. Despite these distributional declines, populations of all three species are present in the San Rafael River, a highly regulated tributary of the Green River, Utah, providing an opportunity for research. Our goal was to determine the timing and extent of movement, habitat preferences, and limiting factors, ultimately to guide effective management and recovery of these three species. In 2007-2008, we sampled fish from 25 systematically selected, 300-m reaches in the lower 64 km of the San Rafael River, spaced to capture the range of species, life-stages, and habitat conditions present. We implanted all target species with a passive integrated transponder (PIT) tag, installed a passive PIT tag antennae, and measured key habitat parameters throughout each reach and at the site of native fish capture. We used random forest modeling to identify and rank the most important abiotic and biotic predictor variables, and reveal potential limiting factors in the San Rafael River. While flannelmouth sucker were relatively evenly distributed within our study area, highest densities of roundtail chub and bluehead sucker occurred in isolated, upstream reaches characterized by complex habitat. In addition, our movement and length-frequency data indicate downstream drift of age-0 roundtail chub, and active upstream movement of adult flannelmouth sucker, both from source populations, providing the lower San Rafael River with colonists. Our random forest analysis highlights the importance of pools, riffles, and distance-to-source populations, suggesting that bluehead sucker and roundtail chub are habitat limited in the lower San Rafael River. These results suggest management efforts should focus on diversifying habitat, maintaining in-stream flow, and removing barriers to movement.
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Ivanyi, Craig Stephen 1960. "Selected aspects of the natural history of the desert sucker (Catostomus (Pantosteus) clarkii)." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/276993.
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Selected aspects of the life history of desert suckers were examined in four southeastern Arizona streams. Diet, age class structure, reproduction, and habitat use were analyzed from field data obtained from April 1987 through October 1988. Adults fed primarily on plant matter, while fry fed almost exclusively on diatoms. Aging of suckers by scales was not possible and length frequencies were too evenly distributed to determine age class structure. In 1988, ovary and teste development occurred from late January through April, with spawning commencing in May. Suckers primarily used pools with high water flow and significant (∼80%) cover formed by tree limbs, branches, leaves, and other debris. Deterioration or loss of suitable habitat is reducing the range of the sucker due to reductions in and manipulations of surface waters.
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Mullins, Anna C. C. "Sucker Punch and the Political Problem of Fantasy to Female Representation." Bowling Green State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1363533555.
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Ulibarri, Roy M. "Habitat Suitability Criteria for Zuni Bluehead Sucker Catostomus discobolus yarrowi and Navajo Nation Genetic Subunit Bluehead Sucker Catostomus discobolus and Comparing Efficiency of AFS Standard Snorkeling Techniques to eDNA Sampling Techniques." Thesis, The University of Arizona, 2016. http://hdl.handle.net/10150/604876.
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I quantified habitat selection for the endangered Zuni Bluehead Sucker Catostomus discobolus yarrowi and the Navajo Nation Genetic Subunit (NNGS) Bluehead Sucker Catostomus discobolus - a recent taxon described from genetic information. Both taxa are found in northern Arizona and New Mexico border regions. I examined fish [≥50 millimeters (mm) total length (TL)] selection of microhabitat conditions (i.e., water velocity, substrate size, overhead cover, water depth, instream cover, and mesohabitat conditions [i.e., pool, run riffle], during summer base flow conditions for NNGS Bluehead Suckers, and during both summer base flow and high spring flow conditions for Zuni Bluehead Suckers in six streams). Electrofishing, seining, and snorkeling were used to evaluate fish occupancy. From this information, I developed stream specific habitat suitability criteria (HSC) and then generalized HSC for each taxon, and tested transferability of the generalized HSC to individual streams. Zuni Bluehead Suckers and NNGS Bluehead Suckers occupied similar habitats: low velocity pools; sand, silt, and pebble substrate; high percent of instream cover; and water temperatures ranging from 2-21°C. However, Zuni Bluehead Suckers selected for low (0-25%) overhead cover where as NNGS Bluehead Sucker selected for high (0-75%) overhead cover. This was likely due to the source of instream cover–aquatic macrophytes that required sunlight in the Zuni Bluehead Sucker streams, and large woody debris falling from overhead branches in the NNGS Bluehead Sucker streams. Suggestions for managers includes maintaining existing cover or artificially construct additional instream cover; promote overhead cover (e.g., maintaining large trees along streams) and pool mesohabitats. In addition to this work I also tested the new method of environmental DNA (eDNA) to further help conservation efforts for these taxa. Environmental DNA has typically been used to detect invasive species in aquatic environments through water samples. I compared the efficacy of eDNA methodology to American Fisheries Society standard snorkeling surveys to detect presence of a rare fish species. My study site included three streams on the Navajo Nation in northern Arizona and northern New Mexico containing Navajo Nation Genetic Subunit Bluehead Sucker Catostomus discobolus and the Zuni Bluehead Sucker Catostomus discobolus yarrowi. To determine sample sites, I first divided entire wetted area of streams into 100-m consecutive reaches. I systematically selected 10 of those reaches for snorkel and eDNA surveys. Water samples were taken in 10-m sections within each 100-m reach, and fish presence via snorkeling was noted in each 10-m section as well. Water samples were collected at the downstream starting point of each reach, and continued upstream in each section 5 to 8 m ahead of the snorkeler. A qPCR was run on each individual water sample in quadruplicate to test for sucker presence or absence. I was able to positively detect both species with eDNA sampling techniques in two out of three streams. Snorkeling resulted in positive detections of both species in all three streams. In streams where fish were detected with eDNA sampling, snorkeling detected fishes at 11-29 sites per stream, where as eDNA detected fish at 3-12 sites per streams. My results suggested that AFS standard snorkeling was more effective at detecting target fish species than eDNA. To improve eDNA sampling, the amount of water collected and tested should be increased. Additionally, filtering water on site may improve eDNA techniques for detecting fish. Future research should focus on standardizing eDNA sampling to provide a widely operational sampling tool similar to electrofishing, netting, and hydroacoustics.
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Sonnenberg, Helga E. "Extractable organochlorine, EOCl, in white sucker, Catostomus commersoni, exposed to bleached kraft mill effluents." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0022/MQ33275.pdf.
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Burns, J. Bracken. "Basic morphological and histological characterizations of the brain of the white sucker, catostomus commersoni." Virtual Press, 1997. http://liblink.bsu.edu/uhtbin/catkey/1048372.
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The white sucker, Catostomus commersoni, is among the many fishes classified as minnows (order Cypriniformes). Minnows are a morphologically diverse teleost (bony fish) group whose brains have been examined previously in both a morphological and experimental context. Two species of minnows, goldfish (Carasius auratus) and European carp (Cyprinus carpio) have been commonly used as model systems for experimental neuroanatomical studies.The purpose of this present study is to catalog the brain of the white sucker for its use in future studies and as a comparative reference for the study of other catostomids. In particular, the neuronal connections of the cranial nerves could be explored once the brain has been characterized. This species was chosen because of its position as the outgroup for all other members of the genus Catostomus, and the fact that it is relatively easy to obtain. This study focuses on two areas: descriptions of the gross morphology of the brain of the white sucker, and histological characterizations of the nuclei of the brain of the white sucker.Department of Physiology and Health Science
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Schalau, Jeff. "Cut Stump Application of Herbicides to Manage Woody Vegetation." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2006. http://hdl.handle.net/10150/144792.
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2 pp.Persistent woody plants can sometimes conflict with gardening and landscape goals. In many cases, plant removal becomes necessary. This may be accomplished through manual stump removal or the use of herbicides. With some knowledge of the life history of the target plant, cut stumps can be safely and effectively treated with herbicides to prevent regrowth. Species lists, safety tips, examples, photos, and non-herbicide alternatives are provided to ensure optimum stump killing success.
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Schalau, Jeff. "Cut Stump Application of Herbicides to Manage Woody Vegetation." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2011. http://hdl.handle.net/10150/239596.
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Brown, Richard S. "Winter ecology of brown trout, white sucker and common carp in the Grand River, Ontario." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0027/NQ51182.pdf.
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Downing, Kevin Francis. "Biostratigraphy, taphonomy, and paleoecology of vertebrates from the Sucker Creek Formation (Miocene) of southeastern Oregon." Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/185976.
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The Sucker Creek Formation exposures at Devils Gate in southeastern Oregon have yielded a significant small mammal fauna of at least thirty small mammal taxa from five stratigraphic horizons. The mammal-bearing portion of the Devils Gate section is more than 200 m thick. Fossil mammals occur in lacustrine and marginal lacustrine deposits lower in the section and occur in overbank and paleosol deposits higher in the section. ⁴⁰Ar/³⁹Ar single-crystal laser-fusion dates on three Devils Gate ashes shows that the age of the mammal-bearing sequence at Devils Gate spans the late early Barstovian land-mammal age with possible overlap into the late Barstovian, as currently defined. Duration of the entire mammal-bearing portion of the Devils Gate section was less than a million years. Both a new ash date from the type section and biostratigraphic correlations between Devils Gate and the type section support considerable temporal overlap between the two exposures. The Devils Gate Local Fauna includes several new taxa: a phyllostomatid bat; two "flying squirrels", Petauristodon sp. A and Petauristodon sp. B; and an eomyid rodent, Leptodontomys sp. A. Several fossil occurrences represent the first record of a taxon in the northern Great Basin and/or in the Barstovian land-mammal age, including: Blackia sp., Schaubeaumys grangeri, Protospermophilus quatalensis, and Pseudadjidaumo stirtoni. The Stagestop locality produced two new taxa, Copemys sp. aff C. esmeraldensis and Mystipterus sp. The Stagestop local fauna is Clarendonian in age. Concretions are an important source of fossil mammals in exposures of the Sucker Creek Formation. Geochemical analyses show that concretions formed through a complex interaction between bone and surrounding volcaniclastic material. Although some superficial bone was consumed during concretion diagenesis, concretion development reduced the chance of prolonged chemical and physical destruction of bone during later soil development. The broad ecological diversity of small mammals recovered from Devils Gate supports an interpretation of the local paleoecology as a mosaic of grassland, forest, and pond/lake-bank environments. Sequential small mammal faunas across a prominent ash event show a generally stable composition with no pronounced ecomorphic differences in pre- and post-volcanic disturbance intervals. Therefore, small mammals do not show analogous ecological patterns to disturbance-driven plant successions in the Sucker Creek Formation. I infer that the local ecosystem recovered from volcanic blasts at a temporal scale below the resolution of time-averaged, post-disturbance paleosols.
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Strohm, Deanna. "Matching Watershed and Otolith Chemistry to Establish Natal Origin of an Endangered Desert Lake Sucker." DigitalCommons@USU, 2015. https://digitalcommons.usu.edu/etd/4416.
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Like many native endemic desert freshwater fish species, the June Sucker (Chasmistes liorus) is currently listed as endangered. Managers have increasingly turned to habitat restoration as a key component to recovery plans. For endangered species, one of the primary outcomes of habitat restoration is that it should result in successful reproduction and recruitment of individuals into the adult population. Confirmation of natural recruitment as a function of habitat restoration can only be achieved by establishing natal origins.
Recent research has proven the validity of otolith microchemistry, a technique that analyzes small quantities of elements, to trace potamodromous fish to their natal tributaries. Previous studies have documented that localized habitats in terms of microchemistry are reflected in otolith composition, thereby potentially making this a valuable way of determining fish origins. The primary goal of this study is to use otolith microchemistry to establish natal origins of June Sucker, ultimately in order to evaluate whether tributary habitat restoration results in natural recruitment. To accomplish this I first determined if the water chemistry among the three main spawning tributaries differed from one another. Second, I determined if the otolith chemistry reflected the otolith chemistry. Lastly, I developed a statistical model capable of classifying fish to their respective tributary based the element:calcium ratios in the otolith microchemistry.
Water chemistry differed significantly among all three spawning tributaries, and I observed a strong and significant relationship between otolith chemistry and water chemistry. The classification models based on otolith element:Ca signatures were capable of accurately classifying individual fish to their natal tributary (classification tree 89% accuracy; random forest model 91% accuracy), increasing the ability to determine if the fish’s origin is wild vs. hatchery. The data obtained from this study will advance the current understanding of the June sucker recruitment dynamics and result in a fundamental improvement in our ability to determine where natural recruitment into the adult spawning population is occurring. In addition, this knowledge may help evaluate factors limiting recruitment in Utah Lake tributaries, identify future restoration localities, and assist effectiveness monitoring of spawning habitat restoration efforts.
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Maloney, Bryan C. "Evaluating Habitat-based Niche Requirements and Potential Recruitment Bottlenecks for Imperiled Bluehead Sucker (Catostomus discobolus)." DigitalCommons@USU, 2017. https://digitalcommons.usu.edu/etd/6325.
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Changes to rivers that alter physical and thermal habitat may cause fish population abundance to decline, due to fewer individuals maturing and entering the adult population. The Weber River has become highly degraded with many dams and diversions altering fish habitat, river volume, velocity, and temperature, and limiting movement between reaches. Bluehead suckers (Catostomus discobolus) occupy only 47% of their historical range and the genetically-distinct Weber River (northern UT) population is declining and contains few young, juvenile fish. My objectives were to determine whether spawning and rearing habitat available in the Weber River may be limiting bluehead sucker reproductive success and population growth. I used reach-based surveys to locate and quantify spawning habitat in the Weber River and Ferron Creek (central Utah), a relatively unaltered river for comparison. I sampled slow-water backwaters near (< 1 km) spawning reaches for juvenile sucker and surveyed habitat characteristics. I conducted laboratory experiments to evaluate the effect different temperature and velocity treatments (12-19°C, 0.004-0.18 m/s) have on juvenile bluehead sucker growth. In the Weber River and Ferron Creek, reaches with gravel (4-64 mm diameter), cobble (64-256 mm diameter), and pools (6-26 pools/km) were used by spawning bluehead sucker. In Weber River backwaters, deeper backwaters contained significantly more juvenile sucker (18-378 sucker; range: 19-87 cm max depth).
Laboratory results indicated that juvenile bluehead sucker growth was greatest in the cooler temperature and slower velocity treatments. Collectively these results suggest spawning habitat is limited by the availability of small, rocky substrate and pools and rearing habitat is limited by the availability of deep, slow backwaters at the optimal temperature. By evaluating factors that may limit bluehead sucker population growth, this study will provide a template for future restoration efforts directed at recovering this imperiled population.
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Hines, Brian A. "Relative Importance of Environmental Variables for Spawning Cues and Tributary Use by an Adfluvial Lake Sucker." DigitalCommons@USU, 2011. https://digitalcommons.usu.edu/etd/1088.
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The federally endangered June sucker (Chasmistes liorus mictus), which is endemic to Utah Lake, UT, historically spawned in all significant tributaries flowing into Utah Lake. However, due to a variety of anthropogenic changes, June sucker spawning is now primarily restricted to the Provo River, the largest tributary to Utah Lake. The purpose of this study was to gain a better understanding of the spawning and early life history of the June sucker. My specific objectives were to determine (1) what environmental factors attract or deter June suckers to certain Utah Lake tributaries for spawning; (2) what cues June suckers to migrate upstream to spawn; (3) if June suckers use more than one tributary for spawning; and (4) what limiting factors exist in these smaller tributaries. I performed weekly trap-netting surveys and installed passive integrated transponder tag interrogation systems into five Utah Lake tributaries during the spring of 2008 to determine if suckers were using multiple tributaries for spawning and to determine the timing and number of fish migrating upstream to spawn. I coupled the trap-netting data (staging) and migration data (tributary use) with a suite of biotic and abiotic environmental variables in a random forest model to establish the strongest relationships that exist between fish migration and environmental factors. I found that June sucker were present at the mouths of all tributaries sampled and migrated up three of the five tributaries during the spawning season. The Provo River was the tributary most used. Evidence of reproduction was found in four of the five tributaries by the presence of larval June sucker. The random forest model, for staging, indicated that lower total dissolved solids of the tributaries influenced higher catch per unit effort at the mouths of the tributaries, but explained only 33% of the variance. The random forest model, for tributary use, performed very well, explaining 85% of the variance and indicated discharge was the most important variable for upstream migration. Specifically, the ascending limb of the hydrograph appeared to cue migration and the descending limb cue spawning. I also found the most likely limiting factors in the smaller tributaries are degraded water quality and available spawning habitat. Results from this study show fish are selecting less degraded streams for spawning. Stream restoration projects, in the smaller tributaries, would likely increase the spawning habitat for June suckers and aid their recovery.
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Kraft, Stephanie A. "Naive Prey versus Nonnative Predators: A Role for Behavior in Endangered Species Conservation." DigitalCommons@USU, 2009. https://digitalcommons.usu.edu/etd/442.
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Fish are one of the most imperiled groups of vertebrates worldwide. Threats to fish fall into one of four general categories: physical habitat loss or degradation, chemical pollution, overfishing, and nonnative species introductions. Nonnative predatory fish often have a devastating impact on native prey, especially with endemic fish, whose restricted distribution and often limited evolutionary history with predators make them particularly susceptible to nonnative predators. One reason nonnative fish are often so efficient predators is that the native fish do not recognize the predator as a threat. Although many studies have examined the role of predator odor recognition, no fish have been shown to possess an innate recognition of the odor of predators unless they share a close co-evolutionary history. Many fish learn to identify novel predators through exposure to a predator's odor in conjunction with a conspecific alarm cue. Alarm cues are substances that are stored in the epidermis of many fish and are released when skin cells are broken. Exposure to novel predator odor in conjunction with alarm cue does not necessarily require a fish to survive a close encounter with a predator to be able to learn to recognize the predator. Here I show that it is possible to train hatchery-raised fish (June sucker, Chasmistes liorus) to recognize a nonnative predator odor (largemouth bass, Micropterus salmoides) through exposure to the odor of a predator that has eaten June sucker. I also show that this training can translate into higher survival in subsequent encounters with predators. I propose that training hatchery-raised fish prior to stocking may increase survival of hatchery-raised fish through anti-predator behavior.
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Ceylan, Sevil Ezgi. "Design And Economical Evaluation Of Sucker Rod And Electrical Submesible Pumps: Oil Wells In A Field, Turkey." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605416/index.pdf.
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There are some alternatives of artificial lift methods to increase the production of oil well or to keep it producing. Sucker rod pumping (SRP) and electrical submersible pumping (ESP) systems are selected for the design and economical evaluation of thirteen oil wells of R field. Although selected wells are already producing artificially, they are redesigned for SRP and ESP. LoadCalC software developed by Lufkin and SubPUMP developed by DSSC are used for SRP and ESP designs respectively. For economic evaluation, the rate of return (ROR) of each design is calculated for ten year period. In technical comparison, advantage of higher production ability with lower power consumption was observed in ESP applications. In wells which have lower production than 100 bpd, SRP takes the advantage as it has the ability of low volume lifting. In economical comparison it was observed that using both methods together was given better result. By increasing the number of wells that were applied ESP, 3.61% of increment in ROR was obtained relative to the present status.
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Barrett, Paul James. "Spatial habitat preference of smallmouth bass (Micropterus dolomieui), roundtail chub (Gila robusta), and razorback sucker (Xyaurchen texanus)." Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/185772.
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Instream Flow Incremental Methodology (IFIM) and Habitat Evaluation Procedure (HEP), require the use of habitat preference curves to model the habitat requirements of fish. The accuracy of these curves has been questioned, particularly when they are applied outside the geographic area for which they were developed. Depth, velocity, substrate, and cover preference curves were developed for adult and juvenile smallmouth bass (Micropterus dolomieui) in Wet Beaver Creek, Arizona, and were compared to those from previous habitat preference studies in Virginia, Oklahoma, and Arizona. Curves for fishes in Wet Beaver Creek also were compared to curves developed using information from the scientific literature. Additionally, curves were developed for adult and subadult roundtail chub (Gila robusta) in Wet Beaver Creek, and adult roundtail chub and razorback sucker (Xyrauchen texanus) in Fossil Creek. The curves for adult roundtail chub were compared between these two locations. Velocity and depth preference curves, for both adult and juvenile smallmouth bass, appeared transferrable among locations. Minor differences between the depth curves were attributable to sampling techniques. Substrate preference curves were not transferrable; smallmouth bass seemed to use whatever substrates were locally available. No conclusion concerning the transferability of cover curves could be made because the definitions used for cover varied widely among investigators. Depth, velocity and substrate preferences of roundtail chub differed between the two streams studied, even though these streams were in the same drainage. The differences may have been related to the presence of smallmouth bass in Wet Beaver Creek; smallmouth bass were not present in Fossil Creek. Habitat preference curves based on depth, velocity, substrate, and cover parameters were developed for razorback suckers in Fossil Creek. No curves have been developed previously for razorback suckers in the lower Colorado River Basin; therefore, no comparisons were possible. This species was probably introduced into Fossil Creek and the habitat preference defined in this study may not represent razorback suckers throughout their range. Razorback suckers do not appear to have successfully spawned in Fossil Creek. This lack of success may reflect the absence of suitable habitat or simply indicate the fish have not reached sexual maturity.
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Callister, Eric V. "A Three-Dimensional, Time-Dependent Circulation Model of Utah Lake." DigitalCommons@USU, 2008. https://digitalcommons.usu.edu/etd/86.
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Spatial and temporal variations of Utah Lake’s flow field were modeled using the Estuary Lake and Computer Model from the Centre for Water Research (CWR-ELCOM) at the University of Western Australia as part of an effort to increase understanding of the lake’s natural processes in order to restore the lake to its pristine, clear-water state and preserve the habitat of the June sucker, an endangered species. The model was validated using temperature measurements taken by sensors in 2007. The water temperature was a strong function of air temperature and incident short wave radiation, and was influenced to a lesser degree by wind speed, wind direction, relative humidity, and cloud cover. The water currents were affected most strongly by wind speed and wind direction. The model also predicted the free drifting paths of June sucker larvae entering Utah Lake through the Provo and Spanish Fork Rivers between mid-April and July.
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Telford, David James. "The potential impact of sexed semen on suckler beef production in the UK." Thesis, University of Newcastle Upon Tyne, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.399561.
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Kreitzer, Joshua Daniel. "Landscape-scale and Macrohabitat-scale Variation in Growth and Survival of Young June Sucker (Chasmistes liorus) in Utah Lake." BYU ScholarsArchive, 2010. https://scholarsarchive.byu.edu/etd/2186.
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The spatial scales at which ecological phenomena are viewed constrain the results of interactions between species and their environments. In lake ecosystems, important dynamics have been identified at the landscape scale and the macrohabitat scale. To determine if landscape-scale effects and macrohabitat-scale effects are important in survival and growth of young June suckers, we compared variation among sites in Utah Lake. Large semi-permeable cages were used to house June suckers in situ at five sites representing landscape-scale variation and two sites representing macrohabitat-scale variation in Utah Lake. We compared survival and growth among sites and related it to resource availability (zooplankton abundances), temperature, and disturbance regime to determine if these were possible drivers of variation. Provo Bay had the highest mean survival and high survival in all four cages. Growth differed among sites: Provo Bay and the northwest site had the highest and lowest mean growth rates, respectively. Survival was higher in vegetated water than open water, whereas growth was significantly higher in open water. Zooplankton densities were highest in Provo Bay and the open water habitat, suggesting a positive relationship between food abundance and growth. Temperature patterns were not consistent with differences in growth among sites. Disturbance was greater in the open lake, which may partly explain the higher survival rates in Provo Bay.
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Singer, Carey. "Student Perception of Social Loafing in University Teamwork." Master's thesis, Faculty of Commerce, 2019. http://hdl.handle.net/11427/31263.
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This study investigated perceptions of social loafing in undergraduate student teams at a South African university. Student participants, randomly assigned to teams, received coursework instruction about team dynamics (including social loafing) and worked together for 12 weeks on a team assignment that was graded at the end of the semester. Students (n = 243) wrote individual reflections on the reasons for social loafing in student teams. Some (n = 24) also participated in an experiential social loafing exercise. These two sources of qualitative data were used in the development of a survey questionnaire, which was completed by 229 students. Fifty-four percent of the student participants (n = 229) perceived social loafing to have occurred in their teams. Four components of perceived social loafing behaviour were identified using factor analysis: unavailability, poor work quality, tech loafing and discussion non-contribution. Loafer apathy (a general lack of care or interest) predicted significant variance in each of the four loafing behaviours and social compensation. Team performance (assignment grades) was not related to the perceived presence social loafing in a team. Rather than reducing effort in response to perceived social loafing (the sucker effect), a social compensation effect occurred in the perceived presence of poor work quality. Effective leadership moderated the relationship between loafer apathy and tech loafing as well as loafer apathy and social compensation. Practical implications and recommendations for future research are presented.
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Thompson, Leslie. "Efficacy of Sucker Control Method and Effect of Topping Height on Axillary Bud Growth in Dark Fire-Cured Tobacco." TopSCHOLAR®, 2001. http://digitalcommons.wku.edu/theses/640.
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The removal of terminal buds (topping) and sucker control are two practices that have an impact on yield and quality of dark tobacco (Nicotiana tabacum L.). Topping breaks apical dominance and encourages the growth of axillary buds (suckers). Following topping, growth regulator chemicals known as suckercides are commonly used to prevent axillary bud growth. Research has demonstrated that topping time, height, and sucker control method influence the quality and yield of the final product. Delaying topping past a critical developmental stage has been shown to reduce leaf yield. Topping height varies among geographical regions with most dark tobacco producers topping to a height of 12 to 16 leaves. Previous studies indicate that plants topped to 16 leaves had higher leaf yields than those topped to 12 leaves if late-season soil moisture was adequate. The opposite effect was observed when late-season soil moisture was below average because the small upper leaves on plants topped to 16 leaves did not receive the moisture needed for proper development. The moisture they did receive could have been diverted to improve the yield and quality of the larger, more valuable leaves if the smaller ones had been removed. Several options exist for chemical control of tobacco axillary buds ranging from contact to systemic materials. Performance of these materials is influenced by several factors including environmental conditions prior to and following application. Research plots were established at Western Kentucky University's Agricultural Research and Education Complex in Bowling Green, Kentucky to evaluate the efficacy of various sucker control methods and evaluate the effect of topping height on axillary bud growth. Data collection was completed in the summer of 2000. Three sucker control methods and three topping heights were investigated. The first sucker control method was a single application of a local systemic suckercide at topping. The second method was a sequential application using a contact suckercide at topping followed by a local systemic applied seven days later. The third method, which served as the control, was topping the plants but not applying any suckercides. The experiment utilized a split-plot design with 9 treatments and 4 replications. The plots consisted of two 7 m rows per plot, with 102 cm row spacing and 89 cm in-row spacing. Data collected include number of suckers per plant and kilograms of sucker biomass per plant. Statistical analysis indicated no sucker control method by topping height interaction; thus sucker control and height data are discussed separately. Suckers per plant and sucker biomass per plant did not differ among those plots receiving a suckercide application. Topping height did not influence sucker number or biomass.
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Grant, Marcus T. "Biomimetic Production Techniques for Mechanical and Chemical Characterization of Sucker Ring Teeth Isoform-12 From the Dosidicus Gigas Squid." Wright State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=wright1484614367176197.
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Gonzalez, David Barrett. "Density Effects on Growth, Survival and Diet of June sucker (Chasmistes liorus): A Component Allee Effect in an Endangered Species." BYU ScholarsArchive, 2004. https://scholarsarchive.byu.edu/etd/707.
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Density-dependence is considered one of the most important regulators of population growth, and it has been documented across a wide variety of species. Typically, population growth rate and components thereof decline with increasing density (i.e., negative density-dependence); however, in species that exhibit high population densities and social behavior, positive density-dependence (i.e., Allee effect) may occur at low density. June sucker, a federally endangered lake sucker endemic to Utah Lake, Utah, USA, occurred historically at high density, and it exhibits coordinated feeding behavior. These characteristics indicate a potential for the existence of an Allee effect at current low population densities. To determine effects of density on growth, survival, and diet, I experimentally manipulated density of young June sucker in replicated enclosures in a natural environment. Larval June sucker were placed in enclosures at four different densities, and growth, survival, and diet of fish, and availability of prey (to determine selectivity) were measured at two time intervals. Both individual growth and survival were significantly lower at the lowest density compared to higher densities, indicative of a component Allee effect. Diets of individuals at low densities were more selective than diets of individuals at intermediate and high densities, suggesting a change in feeding strategy with density. Reduced growth and survival at low density suggests that corresponding, highly selective, feeding strategies may be less efficient than feeding strategies employed at higher densities. Allee effects appear to be an important consideration for recovery of this endangered species, and such effects may be common in historically abundant, but currently rare species.
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Suckart, Isabel [Verfasser], and Daniel [Akademischer Betreuer] Chappell. "Akute Schädigung der endothelialen Glykokalyx bei Kindern während kardiochirurgischen Eingriffen / Isabel Suckart ; Betreuer: Daniel Chappell." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2017. http://d-nb.info/1148276548/34.
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Varo, Barbudo Antonio. "An economic evaluation of the main causes of infertility in the Scottish beef suckler herd." Thesis, University of Aberdeen, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.420120.
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In this study, a Markov chain model based on the cow’s reproductive cycle, and a financial model were developed to study the variation in profitability in Scottish beef suckler herds resulting from the effect on fertility of disease and/or the employment of alternative management practices. The factors affecting fertility to be economically evaluated were chosen based on the results of the regression analysis combined with the recommendations from the literature. The selected factors were: LBS, feeding management, bull management, the effect of animal disease, i.e. BVDV, and restricted suckling. Feeding management was found to be the most important factor diminishing the financial performance of suckler herds. The total gross margin (GM) was found to diminish by 25% between the optima as a result of the application of a poor and a moderate feeding regimes combined with alternatives lengths of breeding season (LBS) ranging from 42 to 147 days. There were also interactions between the effect of poor bull performance and the LBS so that the effect of poor bull performance is markedly increased by the employment of a short LBS. The losses produced by a BVDV infection varied depending on the proportion of animals of the herd infected by this virus, which varies over time. This aspect was estimated using the model of Gunn et al. (2004), which then provided inputs for the estimation of reproductive performance and gross margins using the models reported here. It was found that BVDV drops profitability of Scottish beef suckler herds by up to 23%. Finally, when restricted suckling was applied for alternative LBS and compared with the economic performance as a result of the application of ad libitum suckling, it was found that profitability was improved by 14% between the two optima.
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Earnshaw, Staberg Julia. "“I heard gunfire, thought you might need some help” : En semiotisk studie av tre samtida actionhjältinnor." Thesis, Södertörns högskola, Institutionen för kultur och lärande, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-22059.
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Denna undersökning berör de genuskonstruktioner som finns i skapandet av actionhjältinnor. Jag har valt att undersöka Salt (2010) Sucker Punch (2011) samt Resident Evil:Retribution (2012) Undersökningens frågeställningar är, Hur motiveras användande av våld då det utförs av kvinnliga actionhjältinnor? Vilka arketyper går att urskilja i representationerna av kvinnliga actionhjältinnors våldsutövande? Vilka symboler går att urskilja i kvinnliga actionhjältinnors utövande av våld? Min undersökning grundar sig i teorier om genus med utgångspunkt i Raewyn Connel, för att vidare knyta det samman till Stuart Halls representationsteorier samt stereotypifiering. Teoriavsnittet avslutas sedan med kvinnlig medieforskning från Liesbeth Van Zoonen samt Laura Mulvey. Min tidigare forskning grundar sig i en förklaring till hur den manlige hjälten genom tiden har representeras och vad som är representativt för denne. Den andra delen som utgör min tidigare forskning berör Rikke Schubarts forskning om genomgående arketyper som kvinnliga actionhjältinnor genom tiden blivit porträtterade som, detta för att kunna undersöka huruvida dessa även i samtiden finns kvar i skapandet av kvinnliga actionhjältinnor. I min undersökning har jag kunnat framställa att motivet till våld faller tillbaka på de representationer som finns av kvinnor respektive män, våra förutfattade meningar och stereotypa bilder om vad som är manligt och vad som är kvinnligt. Kvinnliga actionhjältinnor porträtteras även i samtida filmer i form av genomgående arketyper, och de symboler som går att urskilja i våldet är rotade i manligheten.
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Guelbenzu, Gonzalo Maria del Pilar. "Benchmarking and control of bovine viral diarrhoea (BVD) in dairy and suckler herds in Northern Ireland." Thesis, Queen's University Belfast, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.695360.
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Bovine viral diarrhoea (BVD) is a highly significant endemic disease of cattle caused by bovine viral diarrhoea virus (BVDV). Infections with BVDV cause substantial economic losses brought about by its effects on reproduction and exacerbation of concurrent bacterial or viral infections. Since this disease was first described in 1946, diagnostic tools and disease control strategies have evolved considerably. Within Europe, an increasing number of countries have been implementing successful systematic control programmes, highlighting the feasibility and benefits of BVDV control. With its focus on the Northern Ireland industry, this thesis aims to identify and address important knowledge gaps in relation to BVD control in order to implement a systematic disease control programme. Diagnostic tools were reviewed by comparing and validating reverse transcription polymerase chain reaction (RT-PCR) methods, evaluating the testing of serum pools for antibody and by comparing commercial enzyme-linked immunosorbent assay (ELlSA) kits. A non-random survey for antibodies and virus indicated widespread seropositivity to BVDV and bovine herpesvirus type 1 in bulk tank milk samples from 181 dairy herds based across the country. It was followed by a cross-sectional study of dairy and suckler herds, including a risk factor analysis, which looked for evidence of viral circulation in the young stock cohort. It found an overall true seroprevalence of 58.7% (95% Cl: [54.7-62.70/0]). Finally, a genetic typing study in bovine samples collected between 1999 and 2011 did not detect any evidence of BVDV-2 or border disease virus. The analysis indicated that the predominant subtype circulating in Northern Ireland is BVDV-1a and described for the first time the detection of BVDV-1b. Results obtained have been employed to inform decisions on the most appropriate BVD control programme for Northern Ireland, to generate data on available diagnostic investigation tools and to provide a benchmark to assess the success of such a programme.
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Lins, Filipe Campos de Alcantara. "Modelagem e simula??o de um sistema de bombeio mec?nico em po?os direcionais utilizando par?metros concentrados." Universidade Federal do Rio Grande do Norte, 2010. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12939.
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Previous issue date: 2010-05-07This work aims presenting the development of a model and computer simulation of a sucker rod pumping system. This system take into account the well geometry, the flow through the tubing, the dynamic behavior of the rod string and the use of a induction motor model. The rod string were modeled using concentrated parameters, allowing the use of ordinary differential equations systems to simulate it s behavior
Este trabalho visa apresentar a modelagem e a simula??o computacional de um sistema de eleva??o de petr?leo por bombeio mec?nico. Tal sistema leva em considera??o a geometria do po?o, o escoamento do fluido na coluna de produ??o, o comportamento din?mico da coluna de hastes e o uso de um modelo para o motor de indu??o. A coluna de hastes foi modelada de forma a utilizar par?metros concentrados, permitindo o uso de sistemas de equa??es diferenciais ordin?rias na simula??o do comportamento da mesma