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INFORMATION TECHNOLOGY FOR NEXT-GENERATION OF SURGICAL ENVIRONMENTSCABAN, JESUS 01 January 2006 (has links)
Minimally invasive surgeries (MIS) are fundamentally constrained by image quality,access to the operative field, and the visualization environment on which thesurgeon relies for real-time information. Although invasive access benefits the patient,it also leads to more challenging procedures, which require better skills andtraining. Endoscopic surgeries rely heavily on 2D interfaces, introducing additionalchallenges due to the loss of depth perception, the lack of 3-Dimensional imaging,and the reduction of degrees of freedom.By using state-of-the-art technology within a distributed computational architecture,it is possible to incorporate multiple sensors, hybrid display devices, and3D visualization algorithms within a exible surgical environment. Such environmentscan assist the surgeon with valuable information that goes far beyond what iscurrently available. In this thesis, we will discuss how 3D visualization and reconstruction,stereo displays, high-resolution display devices, and tracking techniques arekey elements in the next-generation of surgical environments.
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SPATIAL PRIORITIZATION FOR INVASIVE PLANT MANAGEMENTLevin-Nielsen, Abraham Michael 01 January 2012 (has links)
Invasive exotic plant species have been recognized as serious threats to ecosystems. Extensive research on invasive exotic plant species has primarily focused on the impacts, characteristics, and potential treatments. Decision tools and management models that incorporate these findings often lack input from managers and have limited use in differing invasion scenarios. Therefore, in this study, I created a scientifically-driven framework that incorporates expert input to prioritize watersheds for management within the Inner Bluegrass region of Kentucky. The widely distributed invasive exotic plant Amur honeysuckle (Lonicera maackii) was used as an example species. The framework is built around the Analytic Hierarchy Process and highlights areas in most need of invasive exotic plant management by incorporating weighted landscape variables associated with the invasion process. Results of the prioritization provide useful information for natural resource managers by aiding in the development of control strategies while also creating a valuable framework that can be adapted to various invasive exotic plant species.
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EFFICACY OF DORMANT SEASON HERBICIDE APPLICATION ON CONTROL OF JAPANESE HONEYSUCKLE (<em>LONICERA JAPONICA</em>) FOR HABITAT RESTORATION IN KENTUCKYWeese, Jason L. 01 January 2015 (has links)
Kentucky’s disappearing native grassland communities provide habitat for native flora and fauna. A study was conducted to compare the efficacy of herbicides in control of the invasive Japanese honeysuckle (Lonicera japonica) applied at times when most native species are dormant. Six herbicide mixtures (glyphosate, glyphosate + imazapyr, glyphosate + imazapic, imazapyr, triclopyr + difluphenzopyr, and metsulfuron + difluphenzopyr) were applied in three seasons to assess the effect of application timing of each mixture on honeysuckle control. Herbicides were applied with a CO2 pressurized sprayer at three sites in a randomized complete block design. Pretreatment sampling indicated that Japanese honeysuckle constituted over 70% of plant cover at the study sites. Post-treatment sampling was conducted 60 days, 180 days, 420 days, and 540 days after the final application. All mixtures decreased percent cover of honeysuckle with varying effectiveness. Results indicate that the glyphosate, imazapyr, and metsulfuron + difluphenzopyr mixtures are particularly effective at controlling Japanese honeysuckle when applied at any time between October and April with suitable temperatures. Many native grasses and broadleaf forbs not found during pretreatment sampling also emerged post-treatment, either benefiting from application timing or indicating herbicide tolerance.
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Distribution and environmental associations throughout southwestern Manitoba and southeastern Saskatchewan for the cattail species Typha latifolia, and T. angustifolia, and for the hybrid, T. x glaucaWasko, Jennifer 23 April 2014 (has links)
Cattails (Typha spp.) are invasive and tend to decrease the biodiversity and area of open water of marshes, particularly where the natural hydrological cycles have been altered, as in Delta Marsh, Manitoba. Understanding the distribution of T. latifolia L., T. angustifolia L., their hybrid, T. x glauca Godr., and the environmental variables associated with their habitats, may give valuable insight for managing cattails. The distribution of these cattail species and hybrid were surveyed in 2011 in prairie pothole and roadside ditch marshes across southwestern Manitoba and southeastern Saskatchewan. Plants were identified by analysis of microscopic leaf-lamina margin characteristics. T. x glauca was most widespread, followed by T. latifolia, whereas T. angustifolia was rare and only found as far west as central Manitoba. Current understanding of the correlations between cattail invasions and their environment is conflicting and largely based on lacustrine wetland studies. A generalized linear model was developed. The model explained approximately 40% of the variation in T. x glauca distribution in the prairie potholes and ditches. The model included the environmental variables of sediment Olsen-P, sediment nitrate-N, water pH, litter depth, surrounding land use, and the interaction between Olsen-P and nitrate-N. Olsen-P was the most important of these variables, because its removal from the model significantly reduced the residual deviance of the model (P=0.05). In a survey of 13 transects throughout Delta Marsh in 2009, hybrid cattail, T. x glauca, was dominant, T. angustifolia was rare, and T. latifolia was absent. ANOVA linear regression (P=0.05) revealed that above-ground biomass was correlated with mean cattail ramet height, cattail ramet density, and standing litter biomass. Cattail ramet density was negatively correlated with sampling date and positively correlated with standing litter biomass. Mean cattail height was correlated with fallen litter biomass. One-way ANOVA (P=0.05) revealed that fallen litter biomass was lowest in quadrats closer to the open water, and mean cattail height was greatest at the quadrats closest to the open water. While mean cattail height differed depending on whether the cattail stand was a hybrid monoculture or a mixed stand of T. x glauca and T. angustifolia, no other cattail population variables were correlated with stand type. As revealed by one-way ANOVA (P=0.05), water conductivity, sediment texture, total-N, nitrate-N, Olsen-P, and organic-C were not important variables in the distributions of T. x glauca or T. angustifolia at Delta Marsh. Therefore, managing the nutrient levels at Delta Marsh would not likely be important for limiting the distribution of the cattails at this marsh. However, reducing the P concentration in pothole and ditch marshes may limit cattails in those environments.
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Evaluation of treatment cycles on Verbascum thapsus l. (common mullein) at Lava Beds National Monument, CaliforniaRickleff, Heather D. January 2006 (has links)
Common mullein (Verbascum thapsus) is a non-native plant threatening the integrity of natural ecosystems throughout California. Mechanical, chemical, and biological methods have been utilized for control of common mullein. The objective of this study was to determine which of the following treatment cycles is most effective to reduce populations of common mullein at Lava Beds National Monument: annual (once per year), biennial (once every two years), or no treatment. Vegetation type, natural features, site characteristics, and human disturbance were factors considered when analyzing common mullein distribution and abundance. Forty-five pre-existing plots with populations of common mullein were visited during summer 2005. The interrelationship of common mullein with the surrounding high-desert plant communities was assessed by three vegetation sampling methods. Density, cover, and common mullein stages were measured by point-intercept transects, belt transects, and circular macroplots. Simple linear regressions were performed using common mullein density as the dependent variable with multiple independent variables such as shrub, rock, soil, and grass cover. Analysis of variance test showed no significant relationship between density of common mullein and the three treatment cycles (p > 0.05). However, trends observed imply that annual treatment reduces the population of large rosettes and reproductive stalks over no-treatment and biennial treatment. A bivariate correlation test found the circular macroplot to be similar to belt transects for measuring common mullein density (r = 0.84). / Department of Natural Resources and Environmental Management
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Invazinių ir polinozes sukeliančių augalų paplitimo analizė ir tvarkymas Pakruojyje / Analysis of Distribution and Management of Invasive and Pollinosis Causing Plants in PakruojisSutkevičiūtė, Rasma 17 July 2014 (has links)
Miestų žalieji plotai – urbanizuotos gamtinės sistemos, vis labiau kelia
mokslininkų ir teritorijų valdytojų susirūpinimą dėl jų alergeninio potencialo ir užterštumo
invazinėmis rūšimis, kurios visokeriopai kenkia žmogui ir gamtai ir plinta iš miestų įsiliedamos
į mažiau antropogenizuotas gamtines sistemas. Šiame darbe aprašyti dėsningumai ir pateikti
duomenys naudingi Pakruojo miesto gyventojams ir mokslininkams.
Darbo tikslas – ištirti kokie, invaziniai ir polinozes sukeliantys augalai aptinkami
ir kaip jie paplitę Pakruojyje; nustatyti invazinių ir polinozes sukeliančių augalų ir jų sąžalynų
paplitimo vietas; atlikti žaliųjų plotų šienavimo darbų įvertinimą Pakruojo mieste; parengti
rekomendacijas, remiantis tyrimų rezultatais, kaip tvarkytis su invaziniais ir polinozes
sukeliančiais augalais Pakruojo mieste.
Išanalizavus invazinių augalų paplitimą Pakruojo mieste 2013 m.- paaiškėjo, jog
Pakruojo mieste dažniausiai aptinkami iš Šiaurės Amerikos atkeliavę augalai: (Acer negundo
L.) 64 radimvietės, (Solidago canadensis L.) 32 radimvietės, (Echinocystis lobata Mi- chx.) 11
radimviečių, (Phalacroloma septentrionale Fern. et Wieg.) 22 radimvietės, (Solidago altissima
L).
Atlikus lauko tyrimus paaiškėjo, jog Pakruojo mieste aptinkamos polinozes
sukeliančios pievų žolių 13 atpažintų rūšių. Gausumu 80% pasižyminčios 2 rūšys: (Phalaris
arundinacea L.), (Lolium perenne L.).
Polinozes sukeliančių piktžolių tyrimas... [toliau žr. visą tekstą] / Urban green areas - urban natural systems are increasingly posing scientists and
land managers 'concerns about contamination of allergenic potential, and invasive species are
harmful to humans and the full nature and spread of urban tunes into less anthropogenic impact
on natural systems. This thesis describes the patterns and provide data useful Pakruojis
residents and scientists.
The aim - to explore how invasive and cause nasal plants are found and how they
are distributed Pakruojyje; identify invasive plants cause nasal and sprouts prevalence ; green
areas to make mowing work in assessment Pakruojis ; develop recommendations based on the
research results, how to deal with invasive plants and cause nasal Pakruojis city.
The analysis of the spread of invasive plants Pakruojis in 2013 years - It turned
out that in Pakruojis commonly found in North American plants arrived (Lat. Acer palmatum
L.) 64 original location (Lat. Solidago canadensis L.) 32 original location ( Lat. Echinocystis
lobata Mi - chx .) 11 location sites ( Lat. Phalacroloma septentrionale Fern . Wiegers et.) 22
original location ( Lat. Solidago altissima L ) .
After field studies showed that Pakruojis detected in nasal cause meadow grass 13
recognized species. Characterized by an abundance of 80% of the 2 species (Lat. Phalaris
arundinacea L.) (Lat. Lolium perenne L.) .
Nasal -causing weed survey was conducted in 2013. Pakruojo... [to full text]
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Woody plant species composition in forest fragments at Muscatatuck National Wildlife RefugeFribley, Laura A. January 2006 (has links)
Several invasive woody plants grow in forest fragments at Muscatatuck National Wildlife Refuge in Seymour, Indiana. The objective of this study was to determine what woody species were growing in two upland forests and to assess the level of dominance that invasive species had in these areas. The variables of depth into the forest and directional aspect were also considered. Thirty-two belt transects were sampled and 54 woody species were found, including six invasive species: Ailanthus altissima (tree-ofheaven), Berberis thunbergii (Japanese barberry), Elaeagnus umbellata (autumn olive), Lonicera japonica (Japanese honeysuckle), Lonicera maackii (amur honeysuckle), and Rosa multiflora (multiflora rose). Importance values were calculated as an indicator of relative species dominance. Detrended Correspondence Analysis and Cluster analysis suggested that the invasive species were grouped on the forest edge transects; aspect was not found to be a determinant in where invasive species grew. Correlation coefficients demonstrated a significant difference between transect depth and the following variables at both forests: woody species density per transect, invasive species dominance, Elaeagnus umbellata density per hectare, and Lonicera japonica dominance. Rosa multiflora was one of the three most dominant understory species in both forests; on the edge transect, it was one of the top two. Soil temperatures were also measured at each transect, but no consistent trends were found within the data. In light of resources available, it is suggested that land managers focus on controlling Rosa multiflora and Ailanthus altissima. / Department of Natural Resources and Environmental Management
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A Study of the Impact of an Introduced Herbivore on Pollinator-mediated Interactions and Female Fitness in 'Lythrum salicaria'Russell-Mercier, Jake L. 09 April 2013 (has links)
Herbivory can have many effects on plant fitness, including altering plant-pollinator interactions and sexual reproduction in angiosperms. Pollinator-mediated interactions may be impacted when herbivores alter plant traits, such as floral display size, that can influence pollinator visitation rates, and, ultimately, the reproductive component of plant fitness. Here I describe an investigation into the indirect effects of feeding by beetles released as a biological control agent, Galerucella calmariensis and G. pusilla, on plant-pollinator interactions and reproductive output in the invasive plant Lythrum salicaria L. (purple loosestrife). During the summer of 2011, three treatments (low, ambient and mechanical herbivory) were applied to 105 plants during the pre-flowering period of growth. At the onset of flowering, a series of pollinator observations were conducted over the course of approximately 1.5 weeks. Several aspects of floral display were affected by the herbivory treatments, including increased inflorescence and flower production in the ambient and mechanical herbivory treatments, relative to the low herbivory treatment. Treatment type did not have a significant effect on the number of pollinator foraging bouts, but had marginally significant effects on the number of flowers probed per pollinator foraging bout and per 30-minutes. Moreover, treatment had a significant effect on the number of switches among the inflorescences on a single plant. I discuss the possibility that the differences in pollinator visitation were mediated by differences in the architecture and the size of floral display. There were no detectable differences in fruit or seed production (i.e., female fitness) among treatments. However, as I discuss, differences in pollinator visitation may affect other unmeasured aspects of fitness, such as the level of inbreeding or the number of seeds sired through male function.
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Human vagus nerve branching in the cervical regionHammer, Niels, Glätzner, Juliane, Feja, Christine, Kühne, Christian, Meixensbeger, Jürgen, Planitzer, Uwe, Schleifenbaum, Stefan, Tillmann, Bernhard N., Winkler, Dirk 25 February 2015 (has links) (PDF)
Background: Vagus nerve stimulation is increasingly applied to treat epilepsy, psychiatric conditions and potentially chronic heart failure. After implanting vagus nerve electrodes to the cervical vagus nerve, side effects such as voice alterations and dyspnea or missing therapeutic effects are observed at different frequencies. Cervical vagus nerve branching might partly be responsible for these effects. However, vagus nerve branching has not yet been described in the context of vagus nerve stimulation. Materials and methods: Branching of the cervical vagus nerve was investigated macroscopically in 35 body donors (66 cervical sides) in the carotid sheath. After X-ray imaging for determining the vertebral levels of cervical vagus nerve branching, samples were removed to confirm histologically the nerve and to calculate cervical vagus nerve diameters and cross-sections. Results: Cervical vagus nerve branching was observed in 29%of all cases (26% unilaterally, 3% bilaterally) and proven histologically in all cases. Right-sided branching (22%) was more common than left-sided branching (12%) and occurred on the level of the fourth and fifth vertebra on the left and on the level of the second to fifth vertebra on the right side. Vagus nerves without branching were significantly larger than vagus nerves with branches, concerning their diameters (4.79mm vs. 3.78mm) and cross-sections (7.24 mm2 vs. 5.28mm2). Discussion: Cervical vagus nerve branching is considerably more frequent than described previously. The side-dependent differences of vagus nerve branching may be linked to the asymmetric effects of the vagus nerve. Cervical vagus nerve branching should be taken into account when identifying main trunk of the vagus nerve for implanting electrodes to minimize potential side effects or lacking therapeutic benefits of vagus nerve stimulation.
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Analysis of Secondary Metabolites from Aspergillus fumigatus and Penicillium nalgiovense : Antimicrobial Compounds from Filamentous Fungi Isolated from Extreme EnvironmentsSvahn, Stefan January 2015 (has links)
This thesis describes the cultivation and extraction of filamentous fungi isolated from extreme environments in the search for new antibiotic compounds. Filamentous fungi are a rich source of medicines including antibiotics, and it is believed that many currently unknown fungal species and bioactive fungal metabolites remain to be discovered. Aspergillus fumigatus and Penicillium nalgiovense strains were isolated from an antibiotic-contaminated riverbed near Hyderabad, India, and soil taken from a penguin’s nest on Paulete Island, Antarctica, respectively. It was anticipated that the extreme conditions within these environments would exert unusual selective pressures on their filamentous fungi, possibly causing the secretion of new bioactive compounds. The cultivation, extraction and analysis of metabolites from the A. fumigatus strain resulted in the isolation of the antimicrobial substance gliotoxin. Subsequent investigations revealed that this strain’s secretion of gliotoxin was increased by as much as 65 % when it was cultivated in the presence of pathogen-associated molecular patterns. These results indicate the existence of a fungal receptor/signaling system for detecting nearby bacteria. The scope for using gliotoxin and the related metabolite bis(methyl)gliotoxin as biomarker metabolites for diagnosing the lethal pulmonary condition invasive aspergillosis was also investigated. Bronchoalveolar lavage fluid from 42 patients with and without possible invasive aspergillosis was extracted and analyzed. The results obtained suggest that gliotoxin and bis(methyl)gliotoxin are not suitable markers for diagnosing invasive aspergillosis. Studies on the P. nalgiovense strain from Antarctica resulted in the isolation of the antifungal agent amphotericin B. The secretion of this compound increased when P. nalgiovense was cultured on a potato-dextrose agar enriched with coconut flakes rather than liquid RPMI 1640 medium. This was the first time amphotericin B was isolated from any organism other than the bacterium Streptomyces nodosus. The results presented in this thesis will be useful in the continuing search for novel bioactive compounds, the diagnosis of fungal infections, and as a source of insight into the interactions between microorganisms. Moreover, they show that even extensively studied fungal genera such as Aspergillus and Penicillium are not completely understood and may produce unexpected or previously unknown bioactive metabolites under appropriate conditions.
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