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Kunnil, Joseph. "Identification Studies of Bacillus Spores Using Fluorescence Spectroscopy." Thesis, University of Canterbury. Physics and Astronomy, 2005. http://hdl.handle.net/10092/1311.
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Fluorescence spectroscopy was examined as a potential technique for identifying aerosol particles like bacterial spores. This technique was used for laboratory measurements on some common biological agent simulants. We have measured the intrinsic steady-state fluorescence emission spectra as a function of the excitation wavelength for several bacterial spores (washed and unwashed) in dry and aqueous suspensions at room temperature using excitation wavelengths from 200 to 600 nm. These measurements were compared to those of common, naturally occurring biological components like fungal spores and pollen and non spore samples like ovalbumin. The spectra of samples were combined into fluorescence profiles or fluorescence fingerprints. Different substrates were used for collection and detection of spores. Each bacterium produces a unique in vitro fluorescence profile when measured in dried and aqueous suspension and exhibits a strong maximum in its fluorescence emission spectrum near 330-340 nm. The fluorescence profiles were reproducible. The complexity of microorganisms made the interpretation of their spectral signature a difficult task. Principal components analysis (PCA) and cluster analysis were done as a data reduction technique for detection and identification from different backgrounds. PCA illustrates that linear combination of detected fluorescence intensities, which are present in different ratios in each of samples studied, can be used to discriminate biological agent simulants from other biological samples. The hydration effects, washing effects and the role of tryptophan on spore fluorescence were also investigated. The emission spectra of the dried spores showed a maximum near 330 nm, suggesting a hydrophobic environment for its tryptophan residues. The aqueous solution of tryptophan showed fluorescence shifted to 360 nm and in ethanol solution the maximum was shifted to 340 nm, suggesting a rather more polar average location of the tryptophan. To find the limit of detection we measured the quantum efficiency (QE) of a few samples. We concluded that spectroscopy techniques coupled with effective interpretation models are applicable to biological simulants agents. Index Heading: Bacteria; Spores; Identification; Fluorescence; Fluorescence Quantum Efficiency; Principal Components Analysis; Cluster Analysis.
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Moor, Jaclyn Marie, and Jaclyn Marie Moor. "The Effect of Background Noise on Multitasking." Diss., The University of Arizona, 2017. http://hdl.handle.net/10150/625351.
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Multitasking in background noise may involve greater cognitive processing demands than multitasking in quiet due to an increase in perceptual demands (Rabbitt, 1968; Pichora-Fuller & Schneider, 2000). This study investigated the effect of background noise in the listening environment on the ability of young adults with normal hearing and older adults with sensorineural hearing loss to perceive speech while performing a secondary task. A dual task paradigm, which included word recognition and visual serial recall, was used to examine ability to divide limited processing resources between two tasks. The number of digits to be recalled was varied in order to test the hypothesis that background noise would degrade multitasking abilities to a greater degree than in quiet for more difficult tasks. Participants included 37 native English speakers between 19-25 years of age with pure-tone thresholds better than or equal to 20 dB HL and 10 English speakers between 58-85 years of age with pure-tone thresholds greater than or equal to 25 dB HL in both ears. The results showed that background noise can have negative effects on the ability to multitask for both younger adults with normal hearing and older adults with hearing loss; however, this effect was greater for the older adults with hearing loss, especially when task demands were increased.
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Ogden, Melinda Anne. "Two-photon total internal reflection microscopy for imaging live cells with high background fluorescence." Thesis, Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/34786.
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Fluorescence microscopy allows for spatial and temporal resolution of systems which are inherently fluorescent or which can be selectively labeled with fluorescent molecules. Temporal resolution is crucial for imaging real time processes in living samples. A common problem in fluorescence microscopy of biological samples is autofluorescence, fluorescence inherent to the system, which interferes with detection of fluorescence of interest by decreasing the signal to noise ratio.
Two current methods for improved imaging against autofluorescence are two-photon excitation and total internal reflection microscopy. Two-photon excitation occurs when two longer wavelength photons are absorbed quasi-simultaneously by a single fluorophore. For this to take place there must be a photon density on the order of 1030 photons/(cm2)(s), which is achieved through use of a femtosecond pulsed laser and a high magnification microscope objective. Two-photon excitation then only occurs at the focal spot, significantly reducing the focal volume and therefore background autofluorescence.
The second method, total internal reflection, is based on evanescent wave excitation, which decreases exponentially in intensity away from the imaging surface. This allows for excitation of a thin (~200 nm) slice of a sample. Since only a narrow region of interest is excited, an optical slice can be imaged, decreasing excitation of out-of-focus autofluorescence, and increasing the signal to noise ratio.
By coupling total internal reflection with two-photon excitation, an entire cell can be imaged while still maintaining the use of lower energy photons to irradiate the sample and achieve two-photon excitation along the length traveled by the evanescent wave. This system allows for more sensitive detection of fluorescence of interest from biological systems as a result of a significant decrease in excitation volume and therefore a decrease in autofluorescence signal. In the two-photon total internal reflection microscopy setup detailed in this work, an excitation area of 20 μm by 30 μm is achieved, and used to image FITC-stained actin filaments in BS-C-1 cells
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Dall'Aglio, Aldo. "Constraining the UV background with the proximity effect." Phd thesis, Universität Potsdam, 2009. http://opus.kobv.de/ubp/volltexte/2009/3871/.
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After the epoch of reionisation the intergalactic medium (IGM) is kept at a high photoionisation level by the cosmic UV background radiation field. Primarily composed of the integrated contribution of quasars and young star forming galaxies, its intensity is subject to spatial and temporal fluctuations. In particular in the vicinity of luminous quasars, the UV radiation intensity grows by several orders of magnitude. Due to an enhanced UV radiation up to a few Mpc from the quasar, the ionised hydrogen fraction significantly increases and becomes visible as a reduced level of absorption in the HI Lyman alpha (Ly-alpha) forest. This phenomenon is known as the proximity effect and it is the main focus of this thesis. Modelling the influence on the IGM of the quasar radiation, one is able to determine the UV background intensity at a specific frequency (J_nu_0), or equivalently, its photoionisation rate (Gamma_b). This is of crucial importance for both theoretical and observational cosmology. Thus far, the proximity effect has been investigated primarily by combining the signal of large samples of quasars, as it has been regarded as a statistical phenomenon. Only a handful of studies tried to measure its signature on individual lines of sight, albeit focusing on one sight line only. Our aim is to perform a systematic investigation of large samples of quasars searching for the signature of the proximity effect, with a particular emphasis on its detection on individual lines of sight.
We begin this survey with a sample of 40 high resolution (R~45000), high signal to noise ratio (S/N~70) quasar spectra at redshift 2.1
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Deigård, Daniel. "The Effect of Acute Background Noise on Recognition Tasks." Thesis, Stockholms universitet, Psykologiska institutionen, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-74415.
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Many studies have investigated the effects of background noise on cognitive functions, in particular memory and learning. But few studies have examined the effect of acute noise on the specific parts of the memory process. The purpose of the current study was to fill this gap in the research. Twenty-three students from Stockholm University were tested with two different semantic programming tasks during different white noise conditions. Working memory capacity and subjective sensitivity to noise was also tested. No significant effects were found on the participants’ recognition scores, but a significant main effect for noise during recognition, as well as a significant main effect of experimental group, was found on response times. The noise effect was positive, which puts the study in conflict with most previous ones. The results could perhaps be explained by the theory of Stochastic Resonance or the Yerkes-Dodson Effect. Other reaction-time related tasks are suggested as future topics of study.
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Khorsandi, Babak. "Effect of background turbulence on an axisymmetric turbulent jet." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=104661.
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The effect of background turbulence on a turbulent jet was investigated experimentally. The primary objective of this work was to study the effect of different levels of the background turbulence on the dynamics and mixing of an axisymmetric turbulent jet at different Reynolds numbers. The secondary objective, which arose during the experiments, was to improve the acoustic Doppler velocimetry measurements which were found to be inaccurate when measuring turbulence statistics. In addition to acoustic Doppler velocimetry (ADV), flying hot-film anemometry was employed in this study. To move the hot-film probe at constant speeds, a high precision traversing mechanism was designed and built. A data acquisition system and LabVIEW programs were also developed to acquire data and control the traversing mechanism. The experiments started by benchmarking the two measurement techniques in an axisymmetric turbulent jet. Comparing the results with those of the other studies validated the use of flying hot-film anemometry to estimate the mean and the root-mean square (RMS) velocities. The experiments also validated the use of ADV for measurement of the mean velocities (measured in three Cartesian directions) and the RMS velocity (measured in the z-direction only). RMS velocities measured by the ADV along the x- and y-direction of the probe were overestimated.Attempts to improve the turbulence statistics measured by the ADV using the post-processing and noise-reduction methods presented in the literature were undertaken. However, the RMS velocities remained higher than the accepted values. In addition, a noise-reduction method was presented in this study which reduced the RMS velocities down to the accepted values. It was also attempted to relate Doppler noise to current velocity, and thus improve the results by subtracting the Doppler noise from the measured RMS velocities in the jet. However, no relationship was found between the Doppler noise and the mean velocity. The effect of different levels of background turbulence on the dynamics and mixing of an axisymmetric turbulent jet at different Reynolds numbers was then investigated. The background turbulence was generated by a random jet array. To confirm that the turbulence is approximately homogeneous and isotropic and has a low mean flow, the background flow was first characterized. Velocity measurements in an axisymmetric jet issuing into two different levels of background turbulence were then conducted. Three different jet Reynolds numbers were tested (Re = UJD/ν, where UJ is the jet exit velocity, D is the exit diameter of the jet, and ν is the kinematic viscosity). The results showed that (compared to the jet in a quiescent ambient) the mean axial velocities decay faster in the presence of background turbulence, while the mean radial velocities increase, especially close to the edges of the jet. At lower Reynolds numbers, the jet structure was destroyed in the near-field of the jet. The increase in the level of the background turbulence resulted in a faster decay of the mean axial velocities. The RMS velocity of the jet issuing into the turbulent background also increased, indicating that the level of turbulence in the jet increases. In addition, the jet's width increased in the presence of the background turbulence. The mass flow rate of the jet decreased in the presence of the background turbulence from which it can be inferred that the entrainment into the jet is reduced. The effect of background turbulence on entrainment mechanisms – large-scale engulfment and small-scale nibbling – is discussed. It is concluded that in the presence of background turbulence, engulfment is expected to be the main entrainment mechanism.L'effet de la turbulence ambiante sur l'évolution d'un jet turbulent est étudié dans le cadre de cette recherche expérimentale. L'objectif primaire de ce travail est l'étude de l'effet de l'intensité de la turbulence ambiante sur l'évolution d'un jet turbulent, à trois nombres de Reynolds différents. L'objectif secondaire est l'amélioration des mesures de vélocimétrie acoustique Doppler qui se sont avérées inexactes au cours de ce travail. Un dispositif à anémométrie à fil chaud volant a aussi été développé pour effectuer des mesures dans le cadre de cette étude. A cette fin, un mécanisme de translation a été conçu pour déplacer la sonde à vitesse constante. Un système d'acquisition de données et des programmes LabVIEW ont été développés pour enregistrer les données et contrôler le mécanisme. De premières expériences (dans un jet turbulent axisymétrique en milieu tranquille) ont prouvé le bien-fondé i) des mesures de vitesses moyenne et moyenne quadratique par anémométrie à fil chaud volant, et ii) des mesures de vitesse moyenne (dans tous le sens) et de vitesse moyenne quadratique (dans le sens z) par vélocimétrie acoustique Doppler. Les mesures par vélocimétrie acoustique Doppler dans les sens x et y étaient surestimées. L'amélioration des mesures de vitesse moyenne quadratique par vélocimétrie acoustique Doppler a été tentée par moyen de techniques de réduction de bruit existantes. Néanmoins, les vitesses moyennes quadratiques restaient surestimées. Une nouvelle technique de réduction de bruit (qui avait pour résultat des vitesses moyennes quadratiques précises) a été proposée dans le cadre de cette étude. En outre, des expériences ayant pour but de quantifier le rapport entre le bruit Doppler et la vitesse de l'écoulement ont été entreprises (pour pouvoir soustraire le bruit Doppler des mesures de vitesses moyennes quadratiques). Cependant, celles-ci n'ont trouvé aucun rapport entre ces deux quantités. Par la suite, l'effet de l'intensité de la turbulence ambiante sur l'évolution d'un jet turbulent axisymétrique, à trois nombres de Reynolds différents, a été étudié. La turbulence ambiante a été produite par moyen d'une maille de jets aléatoires. La turbulence ambiante s'est avérée, par moyen de mesures d'anémométrie à fil chaud volant et de vélocimétrie acoustique Doppler, homogène est isotrope. L'évolution d'un jet turbulent (à trois nombres de Reynolds) émis en milieux turbulents (de deux intensités différentes) a ensuite été étudiée. Les mesures ont démontré que la turbulence ambiante i) réduisait la vitesse axiale moyenne du jet (en augmentant le taux de décroissance), et ii) augmentait la vitesse radiale moyenne du jet (surtout prés du bord du jet). Pour les jets à nombre de Reynolds bas, la structure du jet a été détruite dans le champ proche du jet. Les vitesses moyennes quadratiques du jet émis en milieu turbulent étaient plus grandes, indiquant une croissance du niveau de turbulence dans le jet. En outre, la demi-largeur du jet augmentait en milieu turbulent. Par contre, en environnement turbulent, le débit massique du jet émis a diminué, ce qui implique que le taux d'entraînement du jet est aussi réduit. L'effet de la turbulence ambiante sur les mécanismes de l'entraînement (par engloutissement à grande échelle ou par grignotage) est examiné. Il est conclu que, en environnement turbulent, l'engloutissement est le mécanisme d'entraînement principal.
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Clapham, Caroline Margaret. "The effect of background knowledge on EAP reading test performance." Thesis, Lancaster University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239069.
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Björkholm, Viktor. "Background scheduling in Android and its effect on battery usage." Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-217509.
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Background network communication is an important feature for applications running on smartphone devices. When using the network component on a smartphone, only a portion of the time that the component is awake is used for the transfer. The rest of the time when the component uses energy is known as tail energy. Tail energy can make up for a majority of the battery used for network communication. One approach to lower the overhead energy is to batch transfers instead of running them separately. Another way is to limit network access for applications who use it too often from the background. This thesis investigates improvements in Android from version 4.4 to 5.0 and 7.0 and the scheduling APIs AlarmManager and JobScheduler in how they handle background work. The two factors investigated are how well it batches pending tasks and how often applications in the background are allowed to access the network. The results show an advantage to JobScheduler over AlarmManager in how well it batches background work as well as an advantage to newer versions of Android over older. The results suggest an impact from tail energy and that it could be relevant to batch background work.Nätverkskommunikation i bakgrunden är en viktig funktionalitet för smartphone-applikationer. När nätverksmodulen på en smartphone används så går enbart en del av tiden som den är igång åt till kommunikationen. Resten av tiden när enheten använder energi kallas för ”tail energy”. ”Tail energy” kan utgöra en majoritet av energin som går åt till nätverkskommunikation. En metod för att minska den energiåtgången är att gruppera nätverksanrop för att minska den totala mängden overhead-energi. Ett annat sätt är att begränsa åtkomsten till nätverk för applikationer som använder det för ofta från bakgrunden. Den här rapporten undersöker förbättringar i Android från version 4.4 till 5.0 och 7.0 samt schemaläggnings-APIerna AlarmManager och JobScheduler sett till hur de hanterar bakgrundsarbete. De två faktorerna som avsågs var hur väl de grupperar anrop och hur ofta applikationer tilläts använda nätverksresurser från bakgrunden. Resultaten visar en fördel för JobScheduler över AlarmManager sett till hur väl de grupperar bakgrundsarbete. De visar även en fördel för nyare versioner av Android över äldre. Resultaten implicerar en påverkan av ”tail energy” och påvisar att det kan vara relevant att gruppera bakgrundsarbete.
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Guo, Yixing. "Fluorescence Detection of Biological Thiols." PDXScholar, 2012. https://pdxscholar.library.pdx.edu/open_access_etds/586.
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Glutathione (GSH) is an important biological thiol, it performs significant biological functions such as serving an antioxidant which protect cells from oxidative stress by trapping free radicals which damage DNA and RNA. It is known that abnormal plasma levels of GSH have been linked to various human diseases. Therefore, the rapid, sensitive and highly selective detection of GSH is of great importance for investigating its functions in diseases diagnosis. Interestingly, we found in cetyl trimethylammonium bromide (CTAB) medium, the resorufin-based probe shows an extremely fast, highly selective response to GSH. The result indicates that this dye can be employed to detect GSH in biological samples such as human plasma. Cysteine (Cys) is another important biological thiol which is involved in a variety of significant cellur functions, including protein synthesis, detoxication, and metabolic process, etc. Abnormal levels of Cys are related to many diseases, such as slowed growth, Alzheimer's disease and cardiovascular disease. Thus, the detection and quantification of Cys in physiological media is of great importance. In this thesis, I am going to present two organic fluorescent probes (Resorufin-based probe and SNF probe) for the detection and quantification of Cys. In addition, we prove that they can directly quantify Cys in human plasma. The chemical mechanisms involved in the detection of Cys are discussed.
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Peard, Robert, and mikewood@deakin edu au. "The Effect of social background on the development of probabilistic concepts." Deakin University, 1994. http://tux.lib.deakin.edu.au./adt-VDU/public/adt-VDU20050915.154933.
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This research explores how the social backgrounds of a group of students contributed to their intuitive knowledge in probabilistic reasoning, and influenced their processing of the associated mathematics. A group of Year 11 students who came from families for whom the phenomenon of track gambling formed an important part of their cultural background was identified. Another group consisting of students in the same mathematics course (Year 11 Maths in Society) but from families for whom the phenomenon of gambling in any form was totally absent from their social backgrounds was identified. Twenty students were selected from each group.
The research employed a qualitative methodology in which a phenomenographic approach was used to investigate the qualitatively different ways in which individuals within the two groups thought about concepts involving probabilistic reasoning, and processed the related mathematical skills and concepts. The cognitive processes involved in the applications of probabilistic and related mathematical concepts in a variety of both gambling and non-gambling situations were studied in order to determine whether this culturally based knowledge could be viewed as a type of ethnomathematics.
Data were obtained through individual structured interviews which enabled patterns of reasoning to be compared and contrasted. Analyses of these data enabled intuitive mathematical understandings possessed by the gamblers not only to be identified, but also to be linked with their social backgrounds. Also differences between how individuals in the two groups processed probabilistic and associated mathematical knowledge were determined. This research complements and extends existing knowledge and theories related to culturally-based mathematical knowledge. Implications for further research, for classroom teaching, and for curriculum development in the study of probability in senior secondary mathematics classes are discussed.
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Pearson, Danielle K. "Effect of language background on metalinguistic awareness and theory of mind." Thesis, University of Stirling, 2013. http://hdl.handle.net/1893/20994.
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Research has shown that theory of mind tends to develop in typically-developing children at about the age of 4 years. However, language appears to play a great role in this, particularly as deaf children, particularly those born to hearing parents, display extreme delays in theory of mind development, while bilinguals have been found to develop at a somewhat faster rate than monolinguals. Additionally, effects of culture on theory of mind development remain somewhat unclear, as there have been mixed results in past research. Theory of mind has also been correlated with metalinguistic ability and executive functioning skills, leading to multiple hypotheses regarding what drives theory of mind development. The aim of this doctoral thesis was to examine the relationships between theory of mind, metalinguistic awareness, and executive functioning, as well as to evaluate how language and culture play a role in these relationships. Four studies were conducted in an attempt to seek answers to six research questions surrounding this aim. Study1 evaluated theory of mind, metalinguistic awareness, and executive functioning among hearing nursery children in Central Scotland. Study 2 was aimed at evaluating these same skills among deaf children in the U.S. and U.K., as well as developing a scaling of theory of mind abilities among deaf children. Study 3 assessed these skills among deaf Ghanaian children, as well as evaluating theory of mind abilities among a group of hearing Ghanaian children. Finally, Study 4 compared monolingual and bilingual children on theory of mind, metalinguistic awareness, and executive functioning. Results show that there is a strong link between theory of mind and metalinguistic awareness among hearing children that is not explained by executive functioning skills. This relationship was not apparent among deaf children, who struggle more with theory of mind than metalinguistic awareness. The deaf children in Ghana were delayed compared to their Western peers; hearing Ghanaian children were delayed compared to their Western peers as well, but only slightly. Bilingual children and monolingual children performed similarly on false belief and set-shifting tasks; however, monolingual children outperformed bilinguals on metalinguistic awareness and inhibition tasks, possibly due to low verbal mental age among the monolinguals. Results of the four studies suggest that language does play a part in the relationship between theory of mind and metalinguistic awareness. Due to limited data, cultural effects remain unclear. It is proposed that deaf children’s struggle with theory of mind stems from their difficulty with abstract concepts.
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Aksoy, Fuat Yigit. "Interaction of Metal Nanoparticles with Fluorophores and Their Effect on Fluorescence." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2009. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1240302257150-32578.
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Metal nanoparticles have recently gained popularity in many research areas due to their nanosize-related properties. Depending on the size of the metal nanoparticle, their mode of interaction with electromagnetic radiation and the outcome of this interaction vary; in turn the effect exerted on a protein which is conjugated to a nanoparticle varies, because different sized nanoparticles demonstrate different modes of energy transfer with electromagnetic radiation and molecules conjugated to them. Very small cluster with sizes around 1 – 1.2 nm tend to get excited by incident light and emit fluorescence, whereas larger nanoparticles absorb the incoming light very strongly due to their LSPR. In this study we observed the outcomes of the interaction between two types of nanoparticles, namely gold and gold/silver alloyed nanoparticles with the fluorescence emission of two fluorophores, namely eGFP and rPhiYFP; and demonstrated a bioassay where the fluorescence modulation by gold nanoparticles can be used as the sensing strategy. Lastly, we demonstrated the potential of autofluorescent gold nanoparticles as intracellular reporters.
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Wade, Amanda. "Minimizing the Time of Day Effect Through the Use of Background Music." TopSCHOLAR®, 2004. http://digitalcommons.wku.edu/theses/537.
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The time of day effect has been said to be involved with optimal arousal levels during an individual's preferred time of day. In the present study, invigorating background music was used to increase the arousal level of older adults in the afternoon in order to minimize the time of day effect that can be seen in test performance. The results indicated that invigorating background music had no significant effect on scores of a memory recognition task for older or younger adults. However, younger adults performed better than older adults in all testing combinations, older adults had significantly more false alarms than younger adults, and both younger and older adults performed the recognition task at a faster pace when music was present in the background.
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Masters, Richard. "The effect of students' physics background on their understanding of linear algebra." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0015/MQ54288.pdf.
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Levin, Niva 1958. "THE EFFECT OF BACKGROUND KNOWLEDGE ON COMPREHENSION MONITORING OF LEARNING-DISABLED STUDENTS." Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/276472.
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The purpose of this study was to examine the effect of background knowledge on comprehension monitoring of learning disabled students when reading expository texts with inconsistencies and when topic interest was controlled. Eight fifth- and sixth-grade learning disabled students were asked to rate their levels of knowledge and interest for 30 topics and then answered a background knowledge survey to determine three high background knowledge and three low background knowledge topics, both of medium interest. An expository passage was adopted for each of the six topics, controlling for readability, length, and structure. Each passage contained inconsistencies in the main idea and in the details, and each was followed by ten probe questions. Responses to text inconsistencies were analyzed with percentages, and a non-parametric statistical method was performed on the use of strategies. The results from the study provided additional support for the conceptualization of learning disabled students as inactive learners.
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Allison, J. R. "Observations of the Sunyaev-Zel'dovich effect using the Cosmic Background Imager 2." Thesis, University of Oxford, 2010. http://ora.ox.ac.uk/objects/uuid:c6b10ecf-3b50-4c2a-9ee1-0fe8dd93e580.
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This thesis describes the analysis of pointed thermal Sunyaev-Zel'dovich (SZ) effect data from observations using the Cosmic Background Imager 2 (CBI2). CBI2 is an upgrade to the original Cosmic Background Imager, with antennas that have twice the effective collecting area, and hence provide greater sensitivity on longer baselines. Observations of the thermal SZ effect constrain the line-of-sight integrated gas pressure within clusters of galaxies and, when combined with X-ray data, provide an excellent tool for deriving the physical properties of these large structures. The CBI2 SZ data combine relatively low-resolution with a large field-of-view, and can therefore be used to constrain the gas properties of medium-redshift clusters out to the virial radius. By jointly fitting a suitable analytical model to SZ data and X-ray surface brightness data, it is possible to obtain constraints on the temperature and total mass of the cluster. For the analysis work presented in this thesis I choose to parametrise the gas based upon the known behaviour of the entropy, and the total mass by the Navarro, Frenk and White (NFW) prescription. This model is tested against Hydrodynamic/N-body simulations and is found to reproduce the radial behaviour of key cluster properties. The CBI2 observations presented in this work focus on the REFLEX-DXL clusters, an X-ray luminous sub-sample of the REFLEX survey at z ~ 0.3, which have previously published X-ray surface brightness data. The Bullet Cluster, a significant merger system, is a member of this sample and is presented here as a case study for use of the entropy-based model. The derived total mass and gas mass fraction of this cluster are found to be consistent with results from previous X-ray observations. The derived properties from the REFLEX-DXL sample are used to construct a preliminary set of SZ scaling relations out to the virial radius, and are found to be consistent with the self-similar model for massive clusters.
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Chijoke-Mgbame, Aruoriwo Marian. "The effect of CEO background risks on risk taking and firm performance." Thesis, Middlesex University, 2016. http://eprints.mdx.ac.uk/21274/.
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The motivation for this thesis is founded on the increasing studies on executive compensation as it relates to risk taking and firm performance which has resulted in inconclusive results. A large number of the empirical studies on executive pay have focused on agency theory alone to examine its effect on risk taking behaviour and firm performance. The purpose of this research is to contribute to existing knowledge on executive compensation by incorporating background risk theory as a means through which an understanding of executive compensation and its effects on risk taking and firm performance can be analysed. The background risk theory, suggest that the introduction of an additional risk when one has been committed to result in risk aversion. The study employs data from the London Stock Exchange with a sample of FTSE350 non-financial firms for the period 1997-2010. To achieve the objective of the study, the thesis is divided into three independent but related empirical chapters. The first examines the link between background risk and executive compensation-risk taking relationship. The second empirical chapter examines the effect of background risk on the relationship between executive compensation and firm performance. Lastly, the third empirical chapter examines some determinants of CEO background risk with a particular focus on CEO employment risk. The findings of the first empirical chapter provide strong support for the background risk theory. The study finds that the presence of background risk results in lower risk taking by CEOs. In addition, the study provides instances where background risk combined with the risk in the compensation package leads to risk aversion and less risk taking by the CEO. The second empirical chapter finds that even though compensation may result in better firm performance, the presence of additional risk known as background risk alters the relationship between compensation and firm performance. Specifically, the presence of background risk leads to a negative relationship between compensation and firm performance. The findings of the first two empirical studies inspired further research on the determinants of CEO background risk. The findings reveal that large boards and independent boards, increase the likelihood of CEO employment risk. However, CEO network size reduces the likelihood of employment risk.
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Berry, Danica. "Effect of oral cavity loci and cultural background on responses to capsaicin." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1586358754553389.
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Hiraumi, Harukazu. "Effect of amplitude modulation of background noise on auditory-evoked magnetic fields." Kyoto University, 2009. http://hdl.handle.net/2433/124337.
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Calyjur, Priscila Clara. "Efeitos da mutação mdx no background 129/Sv." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/41/41131/tde-17072015-142001/.
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O camundongo mdx, modelo murino para a Distrofia Muscular de Duchenne (DMD) possui uma mutação de ponto no gene da distrofina que resulta na ausência da proteína no músculo, porém seu fenótipo é brando o que o torna um bom modelo genético e molecular, mas não um bom modelo funcional. Esperando obter um modelo para DMD que tivesse um fenótipo mais fiel ao apresentado pelos pacientes humanos, optou-se por transferir a mutação mdx para o background 129/Sv. Através de cruzamentos sucessivos foram obtidas 3 gerações de animais mdx com background 129/Sv (mdx129) e cada geração foi avaliada funcionalmente por 6 meses. Desde a primeira geração é possível observar que os animais mdx129 são mais fortes do que os mdx originais em background C57BL (mdxC57BL), sendo o oposto do esperado no início dos experimentos. O estudo então foi redirecionado para tentar entender o motivo dessa melhora. Em relação ao padrão histológico, em geral há diferenças entre o mdxC57BL e mdx129. Observa-se também que os animais mdx129 entram no processo de degeneração mais tardiamente que os animais mdxC57BL e seu processo de regeneração se estende por mais tempo. Através de estudos de microarray foi possível observar que os animais 129/Sv apresentam poucos genes diferencialmente expressos (GDEs) em relação aos animais C57BL, portanto os dois backgrounds são muito semelhantes. O mdxC57BL apresenta muito mais GDEs em relação ao seu selvagem (C57BL) do que o mdx129 em relação ao 129/Sv, entretanto, ambos os modelos apresentam mais genes superexpressos do que subexpressos, indicando que as alterações distróficas e regenerativas estão mais associadas com a ativação do que a repressão de genes. Quando os GDEs de ambos os modelos de mdx são distribuídos em categorias funcionais, há o predomínio de genes ligados ao sistema imune e quando essa categoria é omitida para melhor visualização das restantes, observa se que ambos os modelos apresentam categorias funcionais semelhantes, porém com proporções diferentes. No modelo mdx129 se destaca a diminuição da participação da categoria de rota endo/exocítica (tráfego de vesículas) e homeostase e aumento da participação das categorias de matiz extracelular e atividade enzimática. Cada modelo apresenta genes exclusivos, destacando os genes SPP1 e IL1RN na comparação 129/Sv x mdx129F3. O gene SPP1 codifica a proteína osteopontina (OPN) e o polimorfismo rs28357094 neste gene é utilizado como biomarcador de prognóstico para DMD. O papel da OPN na progressão da distrofia não é bem conhecido. Alguns estudos afirmam que a ausência dessa proteína melhora a força muscular de camundongos mdx, enquanto outros apontam que sua participação é necessária para a regeneração muscular. Assim sendo, mais estudos serão necessários para verificar qual seria a via responsável pela melhora fenotípica do modelo mdx129. Já o gene IL1RN codifica a proteína IL-1Ra, a qual é um antagonista de interleucina 1 (citocina pró-inflamatória e pró fibrótica). Portanto o aumento da expressão do gene de seu antagonista sugere que os animais mdx129F3 podem estar mais protegidos do processo inflamatório causado por essas moléculas. Quando analisadas as listas filtradas para músculo esquelético das comparações C57BL x mdxC57BL e 129/Sv x mdx129F3 para a formação de vias metabólicas, foi gerada apenas uma via em ambas as comparações com número relevante de moléculas. A via gerada pela análise da lista C57BL x mdxC57BL possui mais moléculas do que a via gerada pela analise da lista 129/Sv x mdx129F3, porém, todas as moléculas presentes nesta via, estão presentes na via C57BL x mdxC57BL, indicando que mesmo com número diferente de moléculas envolvidas, os genes participam das mesmas vias. Tanto a comparação de cada geração de mdx129 com o 129/Sv como a comparação das gerações entre si mostram que os efeitos da mudança de background estão presentes desde a primeira geração e não se alteram significativamente com os cruzamentos sucessivos.The mdx mouse, murine model for Duchenne Muscular Dystrophy (DMD) has a point mutation in the dystrophin gene that results in the absence of the protein in the muscle, however its phenotype is mild, which makes it a good genetic and molecular model, but not a good functional model. Hoping to obtain a model for DMD with a phenotype that is more similar the patients\', it was chosen to transfer the mdx mutation to the 129/Sv background. Through successive breedings, 3 generations of mdx animals with 129/Sv background were obtained and each generation was functionally evaluated for 6 months. Since the first generation it is possible to observe that the mdx129 animals are stronger than the original mdx with C57BL background. The results were the opposite of what was expected in the beginning of the experiments, therefore the study was redirectioned to try to understand the reason of the improved phenotype. About the general histological pattern, there are differences between mdxC57BL and mdx129. It can be observed that the mdx129 animals enter the degenerative process later than the mdxC57BL animals and the regenerative process lasts longer. Through microarray studies it was possible to observe that the 129/Sv animals present few differentially expressed genes (DEGs) in comparison to the C57BL animals; therefore both backgrounds are very similar. The mdxC57BL presents many more DEGs in comparison to C57BL than mdx129 in comparison to 129/Sv, however both models present more super expressed genes than sub expressed, indicating that the dystrophic and regenerative alterations are more associated to the activation rather than the repression of genes. When the DEGs of both mdx models are distributed in functional categories, there is the predominance of genes related to the immune system and when this category is omitted for the better visualization of the remaining, it can be observed that both models present similar functional categories, but with different proportions. In the mdx129 model we can highlight the decrease in participation of the endo/exocytic pathway (vesicle traffic) and homeostasis categories, and increase in participation of the extracellular matrix and enzymatic activity categories. Each model presents exclusive genes, highlighting SPP1 and IL1RN in the comparison 129/Sv x mdx129F3. SPP1 encodes the protein osteopontina (OPN) and the polymorphism rs28357094 in this gene is used as a DMD prognostic biomarker. The role of OPN in the dystrophy progression is not well known. Some studies claim that the absence of OPN increases the muscle strength of the mdx mouse, while others indicate that its participation is necessary to muscle regeneration. More studies are needed to ascertain what pathway is responsible for the phenotypic improvement of the mdx129 model. The IL1RN gene encodes the protein IL-1Ra, and interleukin 1 antagonist, which is a pro-inflammatory and pro-fibrotic cytokine. Therefore, the increase in the expression of its antagonist suggests that the mdx129F3 animals may be more protected from the inflammatory process caused by these molecules. When the filtered lists for skeletal muscle of the comparisons C57BL x mdxC57BL e 129/Sv x mdx129F3 were analyzed for the formation of metabolic pathways, only one pathway was generated in both comparisons. The pathway generated in the analysis C57BL x mdxC57BL has more molecules that the one generated by the 129/Sv x mdx129F3 list, but all molecules present in the latter are also present in the former, indicating that even with different numbers of molecules involved, the genes participate in the same pathways. The comparisons of each generation of mdx129 with the 129/Sv and the comparison of the generations among each other show that the effects of the background change are present since the first generation and are not altered with the successive breedings.
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Nepal, Suman. "Temperature Dependence of Fluorescence Spectra in Some Common Polymers." University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1502107649096441.
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McCutcheon, James Edgar. "Genetic background influences the effect of neurokinin-1 receptor "knockout" in the mouse." Thesis, University College London (University of London), 2007. http://discovery.ucl.ac.uk/1444819/.
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Strains of mice used in laboratory research differ markedly at a molecular, anatomical and behavioural level. Genetic manipulation in mice has become a widely used tool for the selective study of single genes and has also produced a great diversity of phenotypes. However, the interaction between manipulated genes and background strain has been less well examined. Here, the effect of neurokinin-1 (NK1) receptor disruption is shown to depend heavily on the genetic background of the mouse that it is studied in. NK1_/_ mice have previously been shown to display an anxiolytic and antidepressant-like phenotype, as well as having reduced sensitivity to the rewarding properties of the opiates. Here, after being transferred onto a C57BL/6 (B6) background, the anxiolytic effect of the mutation is lost, as is the differential response to morphine's locomotor stimulating properties. When the mutation is transferred onto a mixed C57BL/6 x 129/sv (B6:129) background the NK1 /_ mouse becomes more sensitive to morphine than wildtype counterparts, although no difference in anxiolysis is evident between the genotypes. Examination of the HPA axis in these animals revealed that B6:129 animals had higher levels of stress-induced corticosterone release than B6. Furthermore, NK1 /_ animals on the B6:129 background expressed higher levels of hippocampal glucocorticoid receptor and exhibited more neurogenesis in the hippocampus than wildtype. No differences in these parameters were observed for the genotypes in the B6 strain. Comparison of CRF and cFos mRNAs did not reveal any differences between genotypes in either strain. These results show that there are important epistatic interactions between genetic background and the NK1 receptor. These findings may be relevant for the treatment of anxiety disorders and opiate addiction in the genetically heterogeneous patient population.
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Liu, Jinjun. "Laser-induced fluorescence spectroscopy of the alkoxy radicals." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1169752930.
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Visscher, Arne. "Fluorescence Studies of Amine-substituted Azaanthracene Metal Complexes." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2016. http://hdl.handle.net/11858/00-1735-0000-0028-87CC-A.
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Brown, Angela Carin Wrenn Steven Parker. "The effect of lipid composition on cholesterol-rich domain size in model membranes /." Philadelphia, Pa. : Drexel University, 2008. http://hdl.handle.net/1860/2809.
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Boggs, Bryan. "An Erbium-Doped 1-D Fiber-Bragg Grating and Its Effect Upon Er3+ Radiative Spontaneous Emission." Thesis, University of Oregon, 2013. http://hdl.handle.net/1794/12949.
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Spontaneous atomic emission is not a process of the isolated atom but rather a cooperative effect of the atom and the vacuum field. It is now well established that spontaneous radiative decay rates can be enhanced or suppressed through the effect of cavities comprising various types of discrete, reflective-mirror type, boundaries. The cavity effect is generally understood in terms of a cavity-induced modification of the vacuum spectral energy density. Recently, interest has grown in the possibility that systems characterized by distributed periodic boundary conditions, such as a spatially varying index of refraction, might be effective in controlling radiative atomic processes.
A semi-classical theory is given that enables an estimate of the size of the lifetime modification of a two-level radiator contained within a three-dimensionally incomplete photonic bandgap structure called a fiber-Bragg grating. Following this is an exploration of a specific system and its effect upon radiative spontaneous emission. It is found through fluorescence line narrowing and frequency hole burning measurements that the observation of lifetime modification of the specific system is complicated due to intra and inter Stark energy migration. A lifetime modification measurement then shows that no change in lifetime is observed beyond the error bars on the measurement results.
The tuning and coherence properties of a short-external-cavity diode laser that may be useful for future time-dependent spectroscopic measurements are examined using a fiber-based, self-heterodyne technique. Coherence properties during active frequency scans are characterized through analysis of time-dependent heterodyne beat signals at the output of a fiber interferometer.
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Falcetta, Dorene E. "The effect of background music on second-grade children's rhythmic and tonal pattern recognition." Thesis, Boston University, 2014. https://hdl.handle.net/2144/10986.
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Thesis (D.M.A.)--Boston UniversityThe purpose of this study was to examine the effects of background music on second-grade students' rhythmic and tonal pattern recognition. As no locatable research has examined the effects of passive listening on the tonal and rhythmic pattern recognition skills of second-grade students, this investigation sought to answer the following research questions: 1) What is the extent ofthe relationship between exposure to repetitive background music and music pattern recognition scores among second-grade children; and 2) What is the extent ofthe relationship between musical preference and music pattern recognition scores among second-grade children? This study was conducted over a period of fourteen weeks. Sixty second-grade students comprised the sample used in this investigation. The participants were randomly assigned to one of two groups: the treatment group, which heard a continuous collection of classical background music every day for a total of sixty minutes per day, five days per week, and the control group, which received no treatment. The standardized test employed in this study was Edwin Gordon's Primary Measures ofMusic Audiation (PMMA), intended for children from kindergarten to grade 3. Additionally, a survey addressing the issue of preference was distributed at the end of the fourteen weeks to the students in the treatment group. All participants were administered the PMMA at the end ofthe fourteen-week testing period. The data gathered in this investigation were analyzed via a two-way Repeated Measures ANOVA. Analysis ofthe PMMA scores revealed statistically significant differences between the control group and the treatment group in the subset of participants with low-to-average music aptitude on the rhythm test. Statistically significant differences were also found between the composite percentile, rhythm raw and rhythm percentile scores of those participants in the treatment group who liked the music versus those who disliked the music. The significant results of this study include: a) those participants who possessed low-to-average music aptitude benefited from the background music program in the area ofrhythmic discriminatory skills; and b) those participants who liked the music performed better on the rhythm test of the PMMA than did those participants who disliked the music.
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Hofmekler, Jonathan. "Investigating the effect of membrane anchoring on photoinduced electron transfer pyrazoline based fluorescent probes." Thesis, Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/42896.
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Fluorescence microscopy is a powerful analytical tool for visualizing biological processes at the subcellular level. In this regard, 1,3,5-triarylpyrazoline based fluorescent probes which act as "turn-on" probes, have been extensively researched. These probes achieve their fluorescence "turn-on" response by inhibition of fluorescence quenching by acceptor-excited photoinduced electron transfer upon binding of an analyte. It has been recently shown that some fluorescent probes used in biological research form colloids composed of nanoparticles, due to their hydrophobic character. This hydrophobic character can also lead to partitioning of the probe into cellular membranes. Colloid formation and membrane partitioning may affect the probes' photophysical properties such as absorption and emission wavelength and quantum yields. Recently, a series of 1,3,5-triarylpyrazolines synthesized in our group by M. T. Morgan, showed no formation of aggregates in aqueous buffer. Surprisingly, these probes increased their fluorescence intensity in the presence of liposomes. The photoinduced electron transfer process is greatly affected by the polarity of the medium in which the probe is used. In this study, the effect of membrane proximity on the photoinduced electron transfer process for pyrazoline based "turn-on" probes has been investigated. A series of water soluble 1,3,5-triarylpyrazolines have been synthesized in which a N,N-dialkylaniline moiety acts as an electron donor and a proton acceptor and an alkylated sulfonamide moiety acts as a molecular anchor for interaction with neutral and anionic liposomes.
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Kadiri, Youssef. "Soil Penetrometer with Ramon Sampling, Fluorescence and Reflected Light Imaging: A Feasibility Study." Thesis, Montana State University, 2005. http://etd.lib.montana.edu/etd/2005/kadiri/KadiriY0505.pdf.
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This thesis describes the feasibility and capabilities of a Fluorescence Imaging and Raman Probe (FIRP). This miniature instrument will combine reflected light and fluorescence imaging and Raman spectroscopy for potential exobiology or terrestrial environmental use. With the help of a penetrometer, the probe might be used to assess the presence of life on Mars and gain an understanding of Martian soil. Furthermore, this thesis will delineate how this penetrometer may be used to detect underground constituents and pollutants present on our own planet. The proposed FIRP will be incorporated into a penetrometer that will go several meters below the surface seeking bio-signatures and information about soil composition. Microscopic imaging with reflected light will provide morphological context, fluorescence imaging can provide biomass detection, and Raman spectrometry can provide chemical identification of imaged material. The fluorescence technique will mainly depend on the performance of a non-cooled low-noise monochrome imaging camera, optical filters, and high efficiency light emitting diodes in the UV and visible. This miniature instrument will be connected by optical fiber to a surface platform that will host the Raman spectrometer and Raman laser excitation source. This thesis will show the experimental results of a bench-top proof of concept system. Images and spectra were collected and analyzed. Important choices and characteristics of the optical design are discussed relative to Raman and fluorescence detection. Finally, the thesis will propose a prototype of a compact device that combines both sensing methods and is compatible with a penetrometer platform.
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Dunbar, Laura L. "The Effect of Music on Impulsivity in College Undergraduate Students with Attention Deficits." Diss., The University of Arizona, 2014. http://hdl.handle.net/10150/322986.
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The purpose of this study was to investigate the effect of music listening on impulsivity as judged by the Conners' Continuous Performance Test (CPT) II v. 5. College undergraduate students were recruited into one of two groups and were administered a computer task (CPT) to complete in an initial condition, a music condition, and a silence condition. One group of participants had no diagnosed history of ADHD while the other participant group had a history of ADHD. The initial condition served as an opportunity for each participant to take the CPT with the researcher present to allow each participant to ask questions before taking the test alone; each participant was then taken to a separate testing room. As all participants were tested in all three conditions, the remaining two (music and silence) were randomly assigned to control for order effect. The music condition involved taking the CPT alone in the testing room with "In a Mello Tone" by Count Basie playing in the background during the test administration. The piece was manipulated to have a tempo of mm = 124 and looped to last the entirety of the CPT (14 minutes). Each participant was administered the CPT in a silence condition, in which the participant was alone in the testing room without other provided stimuli. The final sample was N = 51 with n = 26 enrolled in the typical group and n = 25 enrolled in the group with attention deficits. A significant main effect difference was found by group: the typical group exhibited lower impulsivity levels as compared to the ADHD group based on Commission mean scores. Additionally, significant main effect differences were found by condition (initial, music, and silence). Both the factors of group and condition appear to be independent as no interaction was found. Implications and suggestions for future research were discussed.
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Alexander, Lindsey Sharone. "The effect of genetic background on phosphorus utilization for growth and bone integrity in pigs." [Ames, Iowa : Iowa State University], 2007.
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Udomprasert, Patricia Simcoe Lange Andrew E. "H₀o from Cosmic Background Imager observations of the Sunyaev-Zeldovich effect in nearby clusters /." Diss., Pasadena, Calif. : California Institute of Technology, 2004. http://resolver.caltech.edu/CaltechETD:etd-05132004-184937.
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Rätzel, Dennis. "Tensorial spacetime geometries and background-independent quantum field theory." Phd thesis, Universität Potsdam, 2013. http://opus.kobv.de/ubp/volltexte/2013/6573/.
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Famously, Einstein read off the geometry of spacetime from Maxwell's equations. Today, we take this geometry that serious that our fundamental theory of matter, the standard model of particle physics, is based on it. However, it seems that there is a gap in our understanding if it comes to the physics outside of the solar system. Independent surveys show that we need concepts like dark matter and dark energy to make our models fit with the observations. But these concepts do not fit in the standard model of particle physics. To overcome this problem, at least, we have to be open to matter fields with kinematics and dynamics beyond the standard model. But these matter fields might then very well correspond to different spacetime geometries. This is the basis of this thesis: it studies the underlying spacetime geometries and ventures into the quantization of those matter fields independently of any background geometry.
In the first part of this thesis, conditions are identified that a general tensorial geometry must fulfill to serve as a viable spacetime structure. Kinematics of massless and massive point particles on such geometries are introduced and the physical implications are investigated. Additionally, field equations for massive matter fields are constructed like for example a modified Dirac equation.
In the second part, a background independent formulation of quantum field theory, the general boundary formulation, is reviewed. The general boundary formulation is then applied to the Unruh effect as a testing ground and first attempts are made to quantize massive matter fields on tensorial spacetimes.Bekanntermaßen hat Albert Einstein die Geometrie der Raumzeit an den Maxwell-Gleichungen abgelesen. Heutzutage nehmen wie diese Geometrie so ernst, dass unsere fundamentale Materietheorie, das Standardmodell der Teilchenphysik, darauf beruht. Sobald es jedoch um die Physik außerhalb des Sonnensystems geht, scheinen einige Dinge unverstanden zu sein. Unabhängige Beobachtungsreihen zeigen, dass wir Konzepte wie dunkle Materie und dunkle Energie brauchen um unsere Modelle mit den Beobachtungen in Einklang zu bringen. Diese Konzepte passen aber nicht in das Standardmodell der Teilchenphysik. Um dieses Problem zu überwinden, müssen wir zumindest offen sein für Materiefelder mit Kinematiken und Dynamiken die über das Standardmodell hinaus gehen. Diese Materiefelder könnten dann aber auch durchaus zu anderen Raumzeitgeometrien gehören. Das ist die Grundlage dieser Arbeit: sie untersucht die zugehörigen Raumzeitgeometrien und beschäftigt sich mit der Quantisierung solcher Materiefelder unabhängig von jeder Hintergrundgeometrie. Im ersten Teil dieser Arbeit werden Bedingungen identifiziert, die eine allgemeine tensorielle Geometrie erfüllen muss um als sinnvolle Raumzeitgeometrie dienen zu können. Die Kinematik masseloser und massiver Punktteilchen auf solchen Raumzeitgeometrien werden eingeführt und die physikalischen Implikationen werden untersucht. Zusätzlich werden Feldgleichungen für massive Materiefelder konstruiert, wie zum Beispiel eine modifizierte Dirac-Gleichung. Im zweiten Teil wird eine hintergrundunabhängige Formulierung der Quantenfeldtheorie, die General Boundary Formulation, betrachtet. Die General Boundary Formulation wird dann auf den Unruh-Effekt angewendet und erste Versuche werden unternommen massive Materiefelder auf tensoriellen Raumzeiten zu quantisieren.
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Kotwal, Shernaz. "The effects of background music on the learning of a motor skill." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=35201.
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The purpose of this study was to investigate the effects of easy listening popular music on the learning of a perceptual motor task by elementary school aged children. Specifically, forty nine grade four children were analyzed on learning five variables of a dribbling task either with or without background music.The students' social behaviour for the nonmusic and music groups was also observed and analyzed. Finally, the subjects completed a written questionnaire which helped determine their personal preferences with respect to learning with background music.
A Group (2) by Trial (2) by Dribbling Variables (5) ANOVA with repeated measures on Trial was conducted on the dribbling performance scores. Results showed that there was no significant difference between the nonmusic and the music groups on these dribbling performances for four out of the five dribble variables. However, scores of the music group increased more than those of the nonmusic group for three of the five variables. Subjects in the music group demonstrated a more desirable social behaviour than the subjects in the nonmusic group. In addition, the subjects' responses to the questionnaire showed that an overwhelming number of subjects in both groups preferred to have background music played during activity. Therefore, background music may have an important place in the learning environment in terms of behaviour and attitude, which might ultimately enhance learning.
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Kennedy, James 1983. "The APEX-SZ experiment : observations of the Sunyaev Zel'dovich effect." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=116109.
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The Sunyaev Zel'dovich effect (SZE) is a secondary distortion of the cosmic microwave background (CMB) spectrum produced by galaxy clusters that allows for measurements of intra-cluster gas properties. Current experiments are using large arrays of multiplexed transition-edge sensor bolometers to achieve the sensitivities required for SZE cluster surveys and targeted cluster SZE observations. This thesis describes the APEX-SZ experiment, the first instrument to produce scientific results from observations with such an array. The scientific motivation for the APEX-SZ experiment is discussed, followed by a description of the APEX-SZ experiment and frequency domain multiplexing technologies. We have developed a custom data reduction pipeline for the experiment which uses a variety of filters, both in the temporal and spatial domain to produce 1' resolution maps of the SZE at 150GHz. The results of data analysis for the Bullet cluster (lE0657-56) and Abell 2204 (A2204) are presented. Both clusters are assumed to be isothermal and in hydrostatic equilibrium, allowing a fit to an isothermal beta-model and subsequent mass fraction estimates. The maximum likelihood parameters and constant likelihood 68% confidence intervals are estimated using a Markov-Chain Monte Carlo method to sample the beta-model parameter space. We measure cluster gas mass fractions with r 2500 to be 0.140 +/- 0.035 and 0.058 +/- 0.035 for the Bullet cluster and A2204 respectively. The Bullet gas mass fraction is consistent with previous results from X-ray analysis. The gas mass fraction for A2204 does not agree well with other A2204 observations, however the large scatter in the gas mass fractions determined from previous X-ray and SZE analyses indicates that a more complex density model may be appropriate for this cluster.
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Schirber, Michael Robert. "Sources, sinks and scatterers of the ultra-violet background." The Ohio State University, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=osu1072842778.
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Emsley, Maletsema Ruth. "The effect of cultural background on comprehension of English texts by second language learners of English." Thesis, University of Limpopo, 2011. http://hdl.handle.net/10386/577.
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Thesis (M.Ed. (Language Education)) --University of Limpopo, 2011.This study investigated the effect of cultural background on comprehension of English texts by second language learners. The study specifically aimed at determining whether cultural background had any effect on comprehension of English texts by second language learners and whether the second language learners’ cultural background could help them comprehend unfamiliar texts. The background of the study in this mini dissertation was followed by the discussion on the literature available on this topic. This study followed a case study design which utilized 89 respondents from the Further Education and Training band of a rural secondary school in the north of Limpopo province. Data was obtained through the completion of questionnaires and answering of questions from a comprehension test based on English culture. The findings showed that there was no total comprehension of the text by learners who use English as a second language. Learners of English as a second language need to possess specific cultural schemata to comprehend texts that are unfamiliar to them. This study was informed by the schema theory. There is a significant effect of cultural background on the comprehension of English text by second language learners. KEY WORDS: Schema theory. Culture Comprehension. Cultural background
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Pang, Shuo. "Fluorescence Optofluidic Microscopy and Fluorescence Microscopy Based on the Talbot Effect." Thesis, 2013. https://thesis.library.caltech.edu/7614/1/Pang_Shuo_Thesis.pdf.
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Light microscopy has been one of the most common tools in biological research, because of its high resolution and non-invasive nature of the light. Due to its high sensitivity and specificity, fluorescence is one of the most important readout modes of light microscopy. This thesis presents two new fluorescence microscopic imaging techniques: fluorescence optofluidic microscopy and fluorescent Talbot microscopy. The designs of the two systems are fundamentally different from conventional microscopy, which makes compact and portable devices possible. The components of the devices are suitable for mass-production, making the microscopic imaging system more affordable for biological research and clinical diagnostics.
Fluorescence optofluidic microscopy (FOFM) is capable of imaging fluorescent samples in fluid media. The FOFM employs an array of Fresnel zone plates (FZP) to generate an array of focused light spots within a microfluidic channel. As a sample flows through the channel and across the array of focused light spots, a filter-coated CMOS sensor collects the fluorescence emissions. The collected data can then be processed to render a fluorescence microscopic image. The resolution, which is determined by the focused light spot size, is experimentally measured to be 0.65 μm.
Fluorescence Talbot microscopy (FTM) is a fluorescence chip-scale microscopy technique that enables large field-of-view (FOV) and high-resolution imaging. The FTM method utilizes the Talbot effect to project a grid of focused excitation light spots onto the sample. The sample is placed on a filter-coated CMOS sensor chip. The fluorescence emissions associated with each focal spot are collected by the sensor chip and are composed into a sparsely sampled fluorescence image. By raster scanning the Talbot focal spot grid across the sample and collecting a sequence of sparse images, a filled-in high-resolution fluorescence image can be reconstructed. In contrast to a conventional microscope, a collection efficiency, resolution, and FOV are not tied to each other for this technique. The FOV of FTM is directly scalable. Our FTM prototype has demonstrated a resolution of 1.2 μm, and the collection efficiency equivalent to a conventional microscope objective with a 0.70 N.A. The FOV is 3.9 mm × 3.5 mm, which is 100 times larger than that of a 20X/0.40 N.A. conventional microscope objective. Due to its large FOV, high collection efficiency, compactness, and its potential for integration with other on-chip devices, FTM is suitable for diverse applications, such as point-of-care diagnostics, large-scale functional screens, and long-term automated imaging.
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Hsieh, Yi-Ying, and 謝逸瑩. "The effect on brand memory of ambient odor, background music and background picture." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/85030050091321841301.
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碩士國立中央大學
企業管理研究所
95
There are lots of scholar’s studies interested in the effect on atmosphere of the environment to brand memory gradually in recent years. Do people change the degree of brand memory when their five main sense functions affected by stimuli from the environment? This research discusses the effect on brand memory of three kinds of stimulus which include the sense of olfactory, visual, and aural. We talk about the ambient odor by independent variables (the good and bad smell), the background music (lyrics and no lyrics music), and the background picture (happy and disgusting pictures) affect brand recall, brand recognition, and brand familiarity by dependent variables. The data adopt anova variation analysis and also explain the result of experiment group and contrast group. The subjects are mainly graduated students and university students of national central university. The whole experiment proceeds in a fixed room in the management institute. The result shows that the ambient odor is statistically significant on brand recall, brand recognition, and brand familiarity.The outcome in the good smell is better than bad. The background music is statistically significant on brand recall and brand recognition, but not statistically significant on brand familiarity. However the outcome in background music with words is better than background music with no words. The background picture is statistically significant on brand recall, brand recognition, and brand familiarity. The result in the happy pictures is better than disgusting. In addition, the interaction of ambient odor and background music is statistically significant on brand recall and brand recognition. But the interaction outcome is not statistically significant on brand familiarity. The interaction of ambient odor and background picture is statistically significant on brand recall and brand recognition. But the interaction result is not statistically significant on brand familiarity. The interaction of background music and background picture is statistically significant on brand recall and brand recognition. But the interaction result is not statistically significant on brand familiarity.
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Wang, Fu-Cheng. "Gravitational Lensing Effect on Cosmic Microwave Background." 2004. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-2807200418390300.
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Wang, Fu-Cheng, and 王富正. "Gravitational Lensing Effect on Cosmic Microwave Background." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/78094111841396231865.
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碩士國立臺灣大學
物理研究所
92
Matter distribution in the Universe can cause the gravitational lensing effect, which would contaminate the cosmic microwave background (CMB) pattern we have observed today. So we did the N-body simulation as the matter distribution in the Universe, combined with the ray-tracing method to simulate the gravitational lensing effect. From observation we have found the anisotropy of temperature distribution, which means that there could be anisotropy of energy distribution on the last scattering surface. This implies that there are opportunities to find polarization in cosmic microwave background. Thus we also simulate the temperature, and polarization distribution pattern of cosmic microwave background with the help of the simulation code of my advisor. Add the gravitational lensing effect into the cosmic microwave background pattern, we found from the results that the CMB temperature and polarization are affected mainly in small scale.
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Guan-WeiChen and 陳冠瑋. "Background Noise Cancellation of Temporal Focusing-based Multiphoton Excited Fluorescence Images by Structured Illumination." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/sw6j2x.
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Cournoyer, Lemaire Elise. "The effect of background music on episodic memory." Thèse, 2017. http://hdl.handle.net/1866/20332.
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Boyce, Susan J. "The effect of background information on object identification." 1987. https://scholarworks.umass.edu/theses/2123.
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Mao, Xiaopan. "Surface Roughness Effect on Inverse Partial Fluorescence Yield." Thesis, 2013. http://hdl.handle.net/10012/7838.
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Recently a new x-ray absorption spectroscopy (XAS) called inverse partial fluorescence yield (IPFY) has been developed that is bulk sensitive and free of saturation effects, which also provides a direct measure of total absorption coefficient. However, IPFY was originally formulated for smooth bulk samples, but XAS is often performed on rough samples. To test the applicability of IPFY on rough surfaces, a model is presented and the calculations based on this model are compared to the experimental results measured on NdGaO3. It is shown that the correspondence between calculated and experimental intensities of IPFY is sufficient to corroborate this model a means of estimating the maximum allowable surface roughness size and the optimal detection geometry.
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Wu, Jing-Fen, and 吳靜芬. "Effect of a commercial fluorescence liquid on the color, fluorescence, and surface microstructure of 3Y-TZP." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/18224766657086806899.
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碩士國立臺灣大學
臨床牙醫學研究所
102
Background 3％ mol yttrium-stabilized tetragonal zirconia poly-crystal (3Y-TZP) is becoming one of the most promising restorative materials. To mimic the photoluminescence of natural teeth, manufactories provide a fluorescent liquid applied on the 3Y-TZP. However, there is no document about the capacity of the fluorescent agent to regulate the photoluminescence intensity of 3Y-TZP, the photoluminescence expression, and the effect on the color and microstructure of 3Y-TZP. Purpose The purpose of this study was to explore if using a commercial fluorescent agent was able to regulate the photoluminescence intensity of 3Y-TZP, and to analyze the difference of photoluminescence expression between dyed 3Y-TZP and natural teeth. The color, crystallographic forms, surface morphology, and mean grain size of dyed 3Y-TZP were recorded and the results were compared to undyed 3Y-TZP. Materials and methods Zirconia sample was milled to disc form. Shading process was prior to sintering and the commercial fluorescent agent was applied by dipping and brushing methods. The discs were divided into 3 groups: the undyed control group; the dipping groups; the brushing groups. The dipping groups- F(5)、F(60)、F(600) were immersed in the commercial fluorescent agent for 5 sec., 1 and 10 min., respectively. The brushing groups- F1、F4 were tinted with the commercial fluorescent agent by 1 or 4 strokes respectively. This study was divided into 3 parts: (1) The photoluminescence excitation was observed by naked eyes under UV lamp and measured by photoluminescence spectrophotometer. (2) CIE L*, a*, b* values of various group were measured by digital colorimeter. Color change (&;#8710;E) of various groups was compared to &;#8710;E=3.7. Student t test was performed to detect the difference (at a significance difference of p ≦ 0.05). One-way ANOVA tests (at a significance difference of p ≦ 0.05) were used to evaluate the difference of mean L*, a*, b*, &;#8710;E values among various groups. (3) The crystallographic shapes of C、F(600)、F4 were measured by X-ray powder diffractometer (XRD). Surface structural and chemical differences among C、F(600)、F4 were evaluated using scanning electron microscopy (SEM) and energy dispersive analysis (EDS). The mean grain size was calculated. One-way ANOVA were used to detect the difference (at a significance difference of p ≦ 0.05). Results The results were listed below: (1) The photoluminescence excitation of dyed 3Y-TZP differed from a natural tooth. Their spectra were more concentrated than a natural tooth’s spectra, and the peaks were left-shifted. (2) The color of the photoluminescence of dyed 3Y-TZP was blue-shifted. (3) The commercial fluorescent agent could regulate the photoluminescence intensity of dyed 3Y-TZP by immersion time, and the intensity increased as immersion time increased. The difference of the photoluminescence intensity among F(5), F(60) and F(600) was not detected by naked eyes. (4) The commercial fluorescent agent could regulate the photoluminescence intensity of dyed 3Y-TZP by the number of strokes applied, and the intensity increased as strokes increased. The difference of the photoluminescence intensity between F1 and F4 could be detected by naked eyes. (5) The commercial fluorescent agent changed the color. The commercial fluorescent agent made L* value decreased, and a* and b* values increased. Even these samples with the shortest immersion time or the least applied stroke produced color change detectable by naked eyes, ΔE >3.7 ( p < 0.05). (6) The commercial fluorescence agent led to more color change than light-colored A1 agent (p<0.05). (7) The dipping groups caused more notable color change than the brushing groups as the photoluminescence intensity achieved the same level. (8) Undyed C and F4, F(600) samples were composed mainly of t-ZrO2, and a small quantity of m-ZrO2 content. (9) Different shading methods made microstructure distinct, such as the distribution of coloring pigment, homogeneity of grain size, and mean grain size. The dipping group F(600) had a significantly larger grain size than the control group C and the brushing group F4 ( p < 0.05). Conclusion The commercial fluorescent agent can regulate the photoluminescence intensity by immersion time and the number of the strokes applied. However, the increase of the photoluminescence intensity accompanies with color change. The color change is detectable by naked eyes and even more obvious than light-colored dye agent’s. The brushing method cause less color change than the dipping method as the photoluminescence intensity at the same level. Besides, the brushing method compared to the dipping method can maintain even and adequate grain size, which is thought as a key factor to avoid the low temperature degradation. These results show the brushing method more practical clinically than the dipping method.
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Dall'Aglio, Aldo [Verfasser]. "Constraining the UV background with the proximity effect / Aldo Dall'Aglio." 2009. http://d-nb.info/999955713/34.
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Hsiu-Tsung, Lo, and 羅秀聰. "The effect of background music on the perceived waiting time." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/46050793638197658591.
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碩士輔仁大學
企業管理學系管理學碩士班
99
Waiting is a typical part of our lives; however, in the service industry, waiting usually leads to negative consumer perception, which compounds even more the longer a customer is being placed on hold. Customer satisfaction thus plunges, severely lowering customer loyalty. When financial institutions are unable to eliminate this problem, how they utilize a spectrum of stimuli to minimize the highly subjective consumer perception and emotion thus becomes critical. Music throughout the history has been proven to be effective, especially when it comes to comforting and making people relaxed. Further, research in the past has also shown that music tunes can influence one’s both physical and emotional conditions. The main purpose of this research is to probe into how music presence, as well as what types of music such as pop or classic music, in fact changes overall consumer perceived waiting time, satisfaction, and emotions, if any. This research takes a bank’s customer service representatives as the sample size. The experiment takes place with different kinds of music tunes like pop and classic music being played and with questionnaires surveying how consumers perceive their waiting time, satisfaction and emotions vary in different scenarios. As a result, the experiments have shown clear correlation between music and consumer perceived waiting time and satisfaction; pop music has the most significant positive impact. While waiting, customers actually do feel better listening to pop music as the background music. Thus pop music is the most suitable type of tunes to play to reduce negative consumer emotions and perceptions. Further tests were also conducted to see if familiarity with music tunes, regardless of music types, is closely related to minimizing negative customer perception. The results turn out that no clear relationships existed. Playing the “right” music that sounds nice to consumer reduces their perceived waiting times, that has been shown to be shorter than the actual time waited. Consumers are the source from which financial institutions gain profit. When consumers have to wait, they usually become less satisfied, thus their emotions make their perceived waiting time to be longer than their actual waiting time. Therefore it is highly recommended to those who are especially in the service industry, to play pop music to consumers who are placed on hold. This at least can alleviate their negative feelings and hopefully increase their satisfaction and loyalty.
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Wu, Jhen-Yi, and 吳貞儀. "MEF (Metal-enhanced fluorescence) effect offluorophore based on metal nanoparticles." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/69396303871684462408.
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碩士國立中興大學
生醫工程研究所
102
The main purpose of the thesis is to build the novel fluorescence-detection platform based on the MEF(Metal-enhanced fluorescence) effect between silver nanoparticles and fluorophores. At first stage, the silver nanoparticle was synthesized by a simple reductive step and then modified with four species of organic stabilizers, respectively.(became NP1~NP4) And then, the interactions (fluorescence enhancement, complexation ratio, coordinated orientation) between fluorophores and nanoparticles were investigated by means of spectral diversities from spectromicroscopy. Finally, we built a MEF-sensor platform and then to compare with FON (Fluorescent Organic Nanoparticle).Based on our results, the PVP40000 (polyvinylpyrrole) surface-modified silver nanoparticle (NP2) is the most suitable matrix for MEF platform. Moreover, the MEF effect is molecular-axis (coordinated orientation) dependent. Most important, we can not only build an aqueous fluorescence-detection platform, but also can regulate the fluorescence enhancement pathways between MEF and FON, which can expand the detection range and sensitivity.
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Chia, Chi Chiang, and 蔣佳綺. "Effect of Placement Point of Background Music on Shopping Websites Browsing." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/57217171058482724713.
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碩士國立勤益科技大學
流通管理系
99
Shopping website has attracted a great deal of attention in recent years due to the rapid developing of Internet. In the past, researches of online shopping website have focused on the design of website structure and interface from visual stimulus, few carried on the discussion from the auditory stimulus. Recently some websites start to place background music on online store to attract browsers’ attention. A few researches start to explore the effects of background music of online store on consumer response. These researches supposed that background music exist inevitably. However, this premise is not necessarily to be tenable. Browser masters the broadcast of background music of online website. He or she may stop broadcast momentarily. Then the effects of background music have on way to begin with. It is necessary to enable browsers to accept the existence of background music first before discussing of the effect of background music of online store. This study adopted a laboratory experiment to explore the effects of background music placement point on Shopping Websites browsing. Independent variable where music points place into(entirety off, play wholeness, play at 2 min., play at 4 min., play at 6 min). Dependent variables including EEG record, subjective time perception, memory measure, emotional response and cognitive responses. The results shows, after background music play, the Alpha wave power of channel Fp1, Fp2, F8, T4 and Cz would effected intensity obviously lower than before. It can be seen as a response to higher auditory areas. Subjects whom receive music, most feel pleasure and arouse emotions higher than subjects without music. Nevertheless there's no difference at the placement point. Viewer may regard music play wholeness as a distraction that might results negative feelings, further, adjust volume down or turn off. Therefore, this study suggests shopping sites that could avoid music play at begining to decrease viewer produce negative feelings and possibility of turn off sites.