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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

The balance between positive and negative interactions in a savanna

Batchelor, Margaret Elizabeth, Fowler, Norma L., January 2004 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2004. / Supervisor: Norma Fowler. Vita. Includes bibliographical references.
52

Einfluss von Live-Musikveranstaltungen auf den Tonträgerkonsum : eine explorative Studie

Fischer, Corinna January 2006 (has links)
Zugl.: Bielefeld, Fachhochsch., Diplomarbeit, 2006
53

Assessment of DNA degradation in live spermatozoon using laser tweezers Raman microspectrometry

Raheem-Kizchery, Ruby January 2014 (has links)
Purpose: Sperm nuclear proteins and DNA integrity have been implicated in infertility and treatment failures. High stallion to stallion variability is observed in sperm cryopreservation protocols. The cells are destroyed with harsh chemicals prior to using biochemical assays to test sperm DNA quality. The feasibility of using Raman spectrometry in combination with a laser trap for non-destructive micromanipulation and characterization of DNA damage in motile stallion and human sperm is experimentally investigated in this thesis. Methods: Live stallion sperms were subjected to controlled cellular damage: (a) four grades of chemically induced oxidative stress using Xanthine – Xanthine Oxidase (b) three grades of osmotic stress using PBS and (c) membrane damage using thermal shock. Live human sperm DNA disintegration with time and oxidative stress were explored on fresh, cryopreserved and swim-up categories. The specimens ranged from sub-fertile patients to fertile donors in a limited study. Post-treatment sperms resuspended in sperm media, placed on a quartz coverslip were trapped with a 785 nm, 25 mW laser, using a 1.4 NA, 60X, water immersion microscope objective. A Raman spectrum of a trapped cell was acquired for 20 – 30 seconds. The spectra from 20 – 40 cells from each specimen were analysed in the 630 cm-1 – 1630 cm-1 region using statistical variance and PCA. Results: The Raman spectra from trapped motile sperm head contain intense peaks that did not require smoothing prior to analysis. PCA of the Raman spectra could not resolve the different grades of applied osmotic and oxidative stress in stallion cells. PCA showed high variability between specimens from the same stallion and between stallions, with distinct clustering by ejaculate. Membrane damage study and spectra from extended trapping also showed distinct specimen to specimen difference within and between stallions. Specimen to specimen variability is observed in motility and viability tests on 1000s of stallion cells using CASA and flow cytometry. Human sperms showed some clustering by category, time, stress and motility and appeared more sensitive to the tests than stallion sperms. Conclusions: Raman spectra originate from the dense region of the trapped sperm head and resemble the fingerprint of dense calf thymus DNA. The cells show species specific response to the applied stress/damage. Stallion sperms show high variability between ejaculates that could not be differentiated by stallions. Human cells appear more sensitive to the applied processes. LTRS of live sperms needs further detailed research, cross correlated with other established complementary techniques, to identify spectral bands that are most sensitive to the various grades of induced DNA and membrane damage.
54

Computation of Live Load Deflections for a Composite, Steel-Girder Bridge

Jefferson, Thomas Seth 01 December 2016 (has links)
Current specifications of the American Association of State Highway and Transportation Officials (AASHTO) include restrictions on the live load deflections of highway bridge girders. Conventional practice, which utilizes hand calculations to estimate girder deflections, assumes that all girders of a highway bridge deflect to the same degree. In addition, the conventional equations do not account for AASHTO specifications requiring the evaluation of extreme force effects. As such, the accuracy of the conventional approach for calculating girder deflections is under question. The purpose of this study is, therefore, to check the accuracy of the conventional approach by testing the two aforementioned assumptions made by the equations. A composite steel girder bridge example has been selected from Design of Highway Bridges: An LRFD Approach, Third Edition by Richard M. Barker and Jay A. Puckett. The design example specifies the dimensions for all structural elements, as well as the girder type and spacing. The design example does not include specifications for the bridge bearings, and so bearing pads are designed according to the Illinois Department of Transportation (IDOT) Bridge Manual (2012). This study consists of two steps. First, a hand-calculated live load deflection for the bridge example is derived from the conventional approach (assuming all girders deflect to the same degree and without consideration for extreme force effects). Next, the finite element analysis software, NISA/Display IV, is utilized to model and analyze the real-world deflections of the bridge model. Three live loading conditions are applied to the finite element model, in accordance with AASHTO specifications. For first live load condition, the live loads are positioned at the center of each traffic lane. The second and third conditions apply extreme force effects to an interior girder and exterior girder, respectively. The results for each finite element analysis are then compared with the conventional, hand-calculated deflection. The results of this study contradict the two aforementioned assumptions made by the conventional equations for calculating girder deflections. Firstly, this study demonstrates that interior girders experience a significantly greater live load deflection than interior girders. More importantly, the results indicate that the conventional equations underestimate the live load deflection of an interior girder subjected to extreme force effects. None of the results, however, suggest that the bridge example is at risk of excessive deformation, and so the extent to which these drawbacks present a concern can be left to the discretion of the engineer.
55

Survival and Capture Efficiency of River Otters in Southern Illinois

Rutter, Andrew U 01 December 2017 (has links)
River otter (Lontra canadensis) populations in Illinois have rebounded considerably after >80 years of harvest protection and a successful reintroduction program. However, few studies of river otter ecology exist in the Midwestern U.S. where river otter numbers have increased in recent decades. Capturing study animals safely and efficiently is a critical part of wildlife research, and difficulties associated with live capture of river otters have contributed to the dearth of research on the species. Furthermore, estimating survival rates and identifying causes of mortality are important in effectively managing river otters. To address these knowledge gaps, my objectives were determine survival rates and mortality causes for river otters in southern Illinois, and to measure injury rates of river otters captured using Comstock traps. During 2014-16, I captured 42 river otters 49 times at Crab Orchard National Wildlife Refuge (CONWR) in southern Illinois. Eight river otters (3 M, 5 F) were captured in foot-hold traps during 788 trap nights (1 capture/88 trap nights), and the remaining 34 (19 M, 15 F) were captured in Comstock traps during 2,540 trap nights (1 capture/64 trap nights). I detected no significant differences in efficiency or escape rate between the 2 trap types, but Comstock traps did have higher rates for both unavailability and non-target captures. Eleven of the 20 river otters inspected for injuries received some type of injury as a result of capture in a Comstock trap (55%). The most common injury was claw loss (45%), followed by tooth fracture (25%), and lacerations (10%). The ease of setting the Comstock traps and of releasing non-target captures made them a more appealing option than foot-hold traps; however, river otters have a propensity for doing permanent damage to their teeth when live captured in Comstock traps. My study provides information on the functionality and safety of a novel live capture method for river otters. Thirty-four (16 F, 18 M) river otters were successfully radio-marked and monitored for survival for a total of 8,235 radio-days (¯x days/river otter = 242.2 ± 20.6 [SE throughout]). Two river otters (2 M) died during the period of radio-telemetry monitoring: 1 was trapped during nuisance wildlife control activities at an adjacent fish hatchery, and the other died of unknown causes. Annual survival rates were 1.0 ± 0.00 (lower confidence bound = 0.83) and 0.85 ± 0.09 for females and males, respectively, and similar between sexes (χ_1^2 = 1.7, P = 0.19). Pooled-sex breeding season survival was 0.96 ± 0.04. Trapping was the primary source of mortality over the course of my study. After radio-telemetry ended, 2 river otters were harvested by recreational trappers, at 114 (1 M) and 120 (1 F) weeks post-capture, and 1 male was killed by a vehicle collision at 52 weeks post-capture. Primary mortality sources for river otters in southern Illinois are similar to those reported elsewhere (i.e., trapping and vehicle collisions). Although I found no significant difference in survival rates between sexes, the majority of otters that died during my study were male (4 M, 1 F). As river otters occupying CONWR are protected from harvest, males may be more likely to leave the confines of CONWR, thereby putting themselves at greater risk to recreational trapping mortality. My study provides useful demographic information for Illinois’ recently-recovered river otter population.
56

Hur ska vi spela in? : Tre olika inspelningsmetoder: för- och nackdelar vid studioinspelning

Åberg, William January 2018 (has links)
Jag har många gånger genom mitt liv stött på människor som menar att musik låter bättre live,när musiker spelar tillsammans, jämfört med inspelningar där musikerna har spelat tillklickspår.Syftet med detta arbete har varit att undersöka skillnaderna som uppstår beroende på vilkeninspelningsmetod som används.Genom att spela in tre olika låtar på olika vis har jag undersökt vilka skillnader som uppstår imusiken beroende på inspelningsmetoden. Varje låt har spelats in i tre versioner; live, livemed klick samt instrument för instrument med klick. Ensemblen som använts bestod avtrummor, bas, två gitarrister samt sångerska.Det finns inget som pekar på att en av dessa inspelningsmetoder alltid är att föredra, men mankan dra slutsatser kring vilka element som blir lättare respektive svårare att uppnå i enmusikproduktion. Exempelvis kan det vara lättare att göra naturliga dynamikrörelser närinstrumenten spelas in live. Samtidigt så får inspelningen ett mer städat sound närinstrumenten spelas in ett åt gången.
57

Interacting with the piano : absorbing technology into piano technique and collaborative composition : the creation of 'performance environments', pieces and a piano

Nicolls, Sarah Louise January 2010 (has links)
This thesis explores the expansion of the piano performance environment, using technology to augment the sound, the playing area of the piano and its surroundings, and/or the performer's own body in controlling electronic elements of the music. In particular I examine the extension of piano technique and how this is affected by adding technology. I also discuss collaborative compositional processes in creating co-authored musical works and have given a critical appraisal of the different technological systems used in all of these pieces. I have also introduced ideas about developing the structure of the piano to better suit contemporary techniques and the addition of technological elements in piano playing. These ideas are represented by my own "Inside-out Piano", illustrated within the thesis. Throughout this work many new pieces for piano and live electronics have been generated and I hope these may also be useful as a resource for other pianists exploring their own interactions with the piano.
58

Performance of wit(h)nessing : trauma and affect in contemporary live art

Kuburović, Branislava January 2011 (has links)
This thesis investigates traumatic affectivity and a complex mesh of artistic strategies in contemporary live art and performance that allow a certain material renegotiation and transformation of social and personal traumatic histories. These strategies are analysed not as means of interpersonal transmission of experience through narrative capture and consolation, but of a transmission of affect, where the sense of affective sharing, of ‘wit(h)nessing’ and ‘transmissibility’ of (traumatic) affect is distinguished from the idea of identification, of mirroring, of emotional identification that in fact subsumes the other to the same, to a life as we can readily articulate and regulate it without needing to acknowledge the violence inherent in such articulations. The thesis also explores how the notion of dramaturgy changes when observed from the perspective of trauma. Dramaturgy is here understood as ‘the text (the weave) of the performance’, where performance is seen to encompass a wide range of artistic practices which involve some element of live or recorded performed action. Such definition of dramaturgy becomes especially significant when this text/weave is marked by a traumatic occurrence, which by definition damages, tears down its integrating fabric. How can we address the difficulty, physically and philosophically, of accessing a destructive event through a creative act? As one possible answer, the thesis proposes the notion of ‘dramaturgies of loss’, of a certain ‘melancholy’ or ‘traumatic’ text as a creative answer to the forces of violence. It argues that an awkward, uncomfortable presence of certain misplaced, ‘emptied’ mimetic forms of contemporary dance and performance can be seen to create a parallel topography that can retroact on accepted notions of culture and render what belongs inside or outside of the cultural sphere indeterminate and thus potentially open to change.
59

Development of a microfluidic device for single cell analysis using FT-IR microscopy

Ball, Francis John January 2013 (has links)
Prostate cancer is the second most common cause of cancer fatalities in males in the UK (2006) [1]. Therefore any advances in the diagnosis or screening for this form of cancer will yield significant benefits in the treatment of this disease. FT-IR has already been successfully used to assess and grade prostate biopsies by Gazi et al 2006 [2]. The collection of prostate biopsy is however a highly invasive procedure and as current screening methods are highly sensitive, but not very specific, large numbers of patients are referred for biopsy procedures that later come back as negative for prostate cancer [3]. Harvey et al used Raman spectroscopy to classify live cells of a number of prostate cell lines as a first step towards a possible urine screening protocol for prostate cancer [3]. Due to the complementary nature of Raman and FT-IR spectroscopy a similar live cell study should be possible using FT-IR and the combination of this technique with a high-throughput microfluidic device could lead to a useful screening tool for prostate cancer.The aim of the project was therefore to develop a microfluidic system which would enable higher through-put FT-IR analysis of live single cells in an aqueous carrier solution such as PBS or urine than has been previously possible. The design of the microfluidic device must also account for the fact that the materials used to produce the analysis chamber must be highly transparent to mid-IR radiation. The microfluidic device and peripheral systems must be easily transportable as it will be necessary to perform experiments in multiple locations. A design and manufacturing protocol for such a device has been developed.The development of a spectral contribution removal algorithm for the aqueous carrier fluid will also be necessary in order to allow the accurate interpretation of the IR data obtained. A least squares fitting based spectral subtraction algorithm was developed and validated for this purpose.Although it did not prove possible during the project to investigate the possible application of this device to a prostate cancer screening protocol other applications in cell line classification and drug cell interaction studies were performed and yielded encouraging results.
60

Pilot - Streaming for beginners : How can we make it easier for people to start streaming? / Pilot - Streaming för nybörjare

Blomqvist, Viggo January 2019 (has links)
To broadcast live media to the viewer, more known as streaming, has grown in popularity a tremendous amount the last few years. Despite the large viewerbase and people’s dreams to share their creation with the world it’s still quite difficult to get started as a streamer. How can we make it easier for people to start streaming? This project includes the thought and design process of the development of a new product linefor streamers. The product’s purpose is to offer the correct functions that makes it possible, but also easy for anyone to share their passion with the entire world. Letting anyone in the world not just watch you, but also be a part of the experience. The project resulted in a conceptual starter kit for streaming. The kit includes products that cooperate with each other, giving the user a personal and positive experience when starting out with streaming.

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