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Rockcastle, Siobhan Francois. "Daylight variability and contrast-driven architectural effect." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/65745.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2011.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 127-130).
Natural light is a dynamic and ephemeral tool for expressing the quality of architectural space. As a compliment to more traditional avenues of daylighting research that assess performance in terms of quantitative illuminance goals and glare-based discomfort, my thesis defines light variability and contrast as a finely tuned architectural effect. Under the rapidly growing context of energy conscious research, my thesis attempts to re balance our definition of "performance" to include those perceptual and aesthetic aspects of light that are often disregarded by the world of simulation. Contrast is important to the definition of space and it is essential in understanding how architecture is enhanced and transformed over time by the dynamic and variable characteristics of daylight. Through an analysis of contemporary architecture from around the world, this thesis has developed a new typological language that categorizes architectural space in terms of contrast and temporal variation. Using this system of categorization, my thesis proposes three new metrics for the quantification of contrast and light variability to provide a more holistic analysis of daylight performance.
by Siobhan Rockcastle.
S.M.
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Morton, Jane Elizabeth. "Order effects in auditors' internal control judgments: Belief perseverance versus the contrast effect." Diss., The University of Arizona, 1993. http://hdl.handle.net/10150/186314.
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Prior research suggests that beliefs are affected by the order in which information is processed. However, the empirical evidence with respect to this "order effect" is itself anomalous in that the direction of the bias is inconsistent across studies. This study examines and attempts to reconcile the theory of belief perseverance, which predicts primacy, and the contrast-effect theory, which predicts recency. An "integrated" theory of belief revision is presented which proposes that belief perseverance (the contrast effect) is an increasing (decreasing) function of confidence in beliefs. The theory is formalized by expanding Hogarth and Einhorn's (1992) belief-adjustment model to include the proposed effect of confidence on belief revision. The model's predictions were tested in a field experiment in which subjects received a series of information regarding a hypothetical audit client's internal controls and were asked to assess the likelihood that controls would prevent or detect material misstatement. Half of the information in each series was "positive" (describing internal control strengths), while the other half was "negative" (describing internal control weaknesses). The order of information presentation (positive-negative versus negative-positive) was manipulated between subjects. Confidence was manipulated by varying two factors: task experience and amount of information. The experiment was administered to 50 undergraduate auditing students at The University of Arizona and 85 experienced auditors from two of the Big-Six accounting firms. Half of the subjects in each experience-level group received a "short" series of information, while the other half received a "long" series. Confidence assessments were elicited from subjects in each of the four (experience-level/amount-of-information) subject groups and used to form predictions about order-effect differences between groups. The model's predictions were supported for inexperienced subjects but not for experienced subjects, suggesting that confidence affects the direction of order effects only when task experience is low. Furthermore, when order effects were present for experienced-subject groups, they were in the direction of recency. This suggests that increased task experience may lead to a decrease in belief-perseverance proneness.
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Donohoo, Daniel T. "Accomodation with displays having color contrast." Diss., Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/53872.
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Much concern has been expressed about the ability of the visual display terminal to provide adequate stimuli for accommodation. As a result it has been hypothesized that an observer may have to continually refocus to maintain accommodation on the display and this contributes to the visual fatigue experienced by VDT users. The increased use of multicolor CRTs in the workplace adds yet another factor, chromatic aberration, to affect the observers' accommodation to information presented on the CRT. Two experiments were run to determine the effect of viewing characters of one chromaticity and purity on a background of another chromaticity or purity or chromaticity and purity. The observer's accommodation response was continuously sampled throughout the presentation of each target/background combination. Mean accommodation response and the standard deviation of the mean accommodation response were then calculated to ascertain the effect the target background combination had on the observers' accommodation response. The observers' were also required to perform a visual performance task for each target/background combination.
The data collected indicate that chromatic characters when observed on chromatic background do not provide a strong stimulus for accommodation. Mean changes in the observers accommodation response were all within the depth of field except when characters were viewed on blue backgrounds. The variability in the observers accommodation response was not found to be a good predictor of image quality where only color contrast exists between foreground and surround. Task performance was highly correlated with effective contrast between the target and background as quantified by uniform color space modeling.Ph. D.
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Thomas, Kathleen Theresa. "Do colored overlays improve reading? : a test of the Irlen effect /." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-06162009-063332/.
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Johansson, Isabelle. "The Effect of Contrast Media on Several Common Laboratory Assays." Thesis, Uppsala universitet, Institutionen för kvinnors och barns hälsa, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-356300.
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Contrast media are commonly used as an enhancement in several diagnostic imaging methods, which in today’s healthcare often are combined with blood works in diagnostics and surgical preparations, as well as to follow up on the patient’s recovery. To save time and money for both the hospital and the patients themselves, the ability to carry out both the radiological examination and the blood works within the same hospital visit would be preferred. However, there have been indications of a potential interference from the contrast media used, and therefore a waiting period is in place. The aim of this study was therefore to see if that waiting period was warranted by testing if contrast media does cause a significant interference in the most common analyses. This was investigated by infusing pooled samples with either iohexol or gadoteric acid, the active components of the most common contrast agents, at either a full dosage or a half dosage. These samples were then run by standard protocol and the results compared to control samples. The results showed that while some analyses proved affected, others proved unaffected or only insignificantly so. Some of the affected analyses were sodium, activated partial thrombin time and hemoglobin. While some analyses such as prostate specific antigen and prothrombin time were unaffected. Analysis of more samples is necessary to confirm the results, but the overall consensus is that while most analyses are unaffected the effects are too large and uncertain to comfortably disregard the waiting time.
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Watson, Ian Martin Charles. "The effect of bilingualism on the acquisition of the voicing contrast." Thesis, University of Cambridge, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.625103.
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Griffiths, Stella N. "The effect of intraocular scattered light on the contrast sensitivity function." Thesis, Aston University, 1986. http://publications.aston.ac.uk/14587/.
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Intraocular light scatter is high in certain subject groups eg the elderly, due to increased optical media turbidity, which scatters and attenuates light travelling towards the retina. This causes reduced retinal contrast especially in the presence of glare light. Such subjects have depressed Contrast Sensitivity Functions (CSF). Currently available clinical tests do not effectively reflect this visual disability. Intraocular light scatter may be quantified by measuring the CSF with and without glare light and calculating Light Scatter Factors (LSF). To record the CSF on clinically available equipment (Nicolet CS2000), several psychophysical measurement techniques were investigated, and the 60 sec Method of Increasing Contrast was selected as the most appropriate. It was hypothesised that intraocular light scatter due to particles of different dimensions could be identified by glare sources at wide (30°) and narrow (3.5°) angles. CSFs andLSFs were determined for: (i) Subjects in young, intermediate and old age groups. (ii) Subjects during recovery from large amounts of induced corneal oedema. (iii) A clinical sample of contact lens (CL) wearers with a group of matched controls. The CSF was attenuated at all measured spatial frequencies with the intermediate and old group compared to the young group. High LSF values were found only in the old group (over 60 years). It was concluded that CSF attenuation in the intermediate group was due to reduced pupil size, media absorption and/or neural factors. In the old group, the additional factor was high intraocular light scatter levels of lenticular origin. The rate of reduction of the LSF for the 3.5° glare angle was steeper than that for the 30° angle, following induced corneal oedema. This supported the hypothesis, as it was anticipated that epithelial oedema would recover more rapidly than stromal oedema. CSFs and LSFs were markedly abnormal in the CL wearers. The analytical details and the value of these investigative techniques in contact lens research are discussed.
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Shoots-Reinhard, Brittany. "Not all contrast effects are created equal the effect of extent of processing on contrastive judgments /." Columbus, Ohio : Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1211542250.
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Dai, Zhijie. "Delay Discounting, Probability Discounting, Reward Contrast and Gambling: A Cross-Cultural Study." Thesis, University of Canterbury. Psychology, 2012. http://hdl.handle.net/10092/7128.
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Problem and pathological gambling has become an increasing public health concern worldwide in recent years, and individuals from China and East Asian countries may be especially vulnerable. Knowledge of how individuals make choices between outcomes that are delayed or uncertain, and of potential differences in decision making across cultures, may contribute to our understanding of factors which increase the risk of problem gambling. Our research is based on a discounting perspective in which the value of a delayed or uncertain reward decreases according to the time until or the odds against its receipt, respectively. We use experimental procedures in which individuals make a series of hypothetical choices so as to estimate an indifference point – an amount of money available immediately or with certainty – that is equal in subjective value to a delayed or uncertain reward. Our starting point is the hypothesis that reward contrast – in which the subjective value of a reward varies inversely with amount of a prior reward – plays a role in choice between delayed or probabilistic outcomes and might contribute to problem gambling. This thesis describes four experiments which investigate these ideas. Experiments 1 and 2 establish that reward contrast is a reliable phenomenon in choice. Indifference points for an intermediate reward ($475/$525) varied as predicted if its subjective value was larger when the individual had previously been making choices with a smaller amount ($50) and smaller when previously making choices with a larger amount ($5,000). Reward contrast was obtained for both delayed and probabilistic choice, using between-subjects (Experiment 1) and within-subjects (Experiment 2) designs. Experiment 3 used a computerized Card Playing Game (CPG) as an analogue gambling task and also measured delay discounting using the same task as Experiment 2. Participants began with an initial stake and could win or lose 10% of the stake with each card that they played. The critical aspect of the procedure was that the probability of winning for each card decreased as more cards were played. Participants played the CPG four times with stakes of $50, $500, $5,000 and $500 (order of $50 and $5,000 was counterbalanced). Results showed that performance on the CPG improved over successive trials, suggesting that participants learned the contingencies in the task. Although this confounded our attempt to measure reward contrast within-subjects, participants who had a $50 stake in the first deck performed better in the second deck with a $500 stake than those who had a $5,000 stake in the first deck, consistent with reward contrast. Results from the delay discounting task were correlated with CPG performance, showing that participants who had lower reward contrast and discounting rates, and greater magnitude effects won more money on the CPG task. Experiment 4 used a larger sample (N = 182) with both Chinese and Caucasian (New Zealand European) participants and recruited individuals with gambling histories, and compared performance on delay and probability discounting tasks and the CPG. Results showed that Chinese participants had higher delay discounting rates and lower probability discounting rates when data were analyzed according to the area under the discounting curve (AUC). Gamblers (those participants with scores on the South Oaks Gambling Screen [SOGS; Lesieur & Blume, 1987] > 1) were less risk averse in probability discounting and had reduced magnitude effects in delay discounting and performed more poorly on the CPG. Closer analysis of the probability discounting data showed that compared with Caucasians, Chinese were more risk averse for high probabilities of reward outcome, and less risk averse for low probabilities. Although results do not suggest that individual differences in reward contrast, as measured using our within-subjects delay discounting task, play a significant role in the maintenance of gambling behavior, the cross-cultural differences in delay and probability discounting in Experiment 4 suggest some factors that might contribute to gambling. In the General Discussion, we propose an account of the probability discounting results in terms of a tendency toward dialectical thinking and emotions in Chinese culture. Based on this result and previous research, we propose a framework for the cross-cultural analysis of risky decision making, and consider some of its broader implications for both research in decision making and issues of globalization.
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Masson, Andrªe P. "The effect of aging and visual impairments on spatio-temporal contrast sensitivity." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq25919.pdf.
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Perron, Adena Marie. "The effect of vigabatrin treatment on contrast sensitivity in a pediatric population." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ63152.pdf.
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Dimitrakopoulos, Christos. "The contrast effect in judgments of physical attractiveness of self and others." Thesis, University College London (University of London), 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243370.
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Denison, Timothy Allman 1970. "Optical contrast between transparent materials through external modulation of the Faraday effect." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/49626.
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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1998.Includes bibliographical references (leaves 99-101).
/ Timothy Allman Denison.
M.S.
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Haigh, Julian Saunders. "Investigation in to the Effect of Spin Locking on Contrast Agent Relaxivity." PDXScholar, 2015. http://pdxscholar.library.pdx.edu/open_access_etds/2496.
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The current trend in magnetic resonance imaging (MRI) is towards higher external magnetic field strengths (B0) to take advantage of increased sensitivity and signal to noise ratio (SNR). Unfortunately, as (B0) increases the effectiveness (relaxivity) of clinical gadolinium (Gd3+)-based contrast agents (CAs) administered to enhance image contrast is significantly reduced. Excellent soft tissue contrast can be generated with current agents despite their non-optimum relaxivities but necessitates large doses. The limits of detection of a CA at high B0 fields can be lowered by recovering the lost relaxivity and is a pre-requisite to the goal of molecular imaging in which CAs are bound to biomarkers of pathology that exist at very low concentrations. Traditional methods for increasing the detectability of CAs have focused on optimizing critical parameters identified from the Solomon-Bloembergen-Morgan (SBM) theory that affect relaxivity. Gains in relaxivity with these methods to date have been modest and are far from the theoretical maximum possible. Although researchers continue to investigate novel complexes that provide improved relaxivities, any such complex would require a lengthy and costly approval process with the U.S. Food and Drug Administration (FDA). Therefore, a method that affords improved relaxivities of current clinically approved CAs, particularly at high B0 fields, that could be adopted into clinical practice rapidly, is of great interest.
Spin locking is a nuclear magnetic resonance (NMR) technique that was introduced for imaging in 1985, but has received very little attention in combination with Gd3+-based CAs. The technique employs a low power long duration radiofrequency (RF) pulse (B1) parallel to the net magnetization in the x,y-plane. This locks the magnetization into lower precessional frequencies around an "effective" field (Beff) that is reduced with respect to B0 but maintains the high field advantages required for imaging. When considered in the rotating frame, longitudinal relaxation of the magnetization against Beff exhibits shorter time constants (T1p) expected at these lower precessional frequencies. This leads to higher relaxivities, which has implications for increasing CA detectability.
The experiments described herein show that rotating frame longitudinal relaxivities (r1p) for current clinical Gd3+-based CAs are essentially independent of the strength of the spin lock pulse (yB1) as predicted by theory. This result is important because it allows the value of yB1 to be neglected when comparing r1p of Gd3+-based CAs across several B0 fields. The magnetic field dependence of r1p for all clinical agents showed that relaxivity, lost by moving to higher fields, could be "recovered" and that r1p was sensitive to the rotational correlation time constant (TR) of the agent. Using high molecular weight Nanoassembled capsules (NACs) containing a Gd3+-based CA to probe this finding further, we were able to generate relaxivities at high field up to an order of magnitude greater than clinical agents at current imaging fields. These are beyond anything previously reported, or likely to be, with current techniques. Finally, we demonstrated that by spin locking Mn2+ agents, relaxivities at high field increased by a factor of ~ 30 than without spin locking, due to their larger dependence on scalar coupling. These findings show the potential of spin locking to increase detection limits dramatically at high field and are an exciting development towards the goal of molecular imaging.
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Diamond, Mark R. "The effect of saccades on visual sensitivity and time perception /." Connect to this title, 2002. http://theses.library.uwa.edu.au/adt-WU2003.0038.
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Sharma, Saloni. "The effect of L-dopa on contrast sensitivity in normal subjects using functional magnetic resonance imaging." Morgantown, W. Va. : [West Virginia University Libraries], 2003. http://etd.wvu.edu/templates/showETD.cfm?recnum=2973.
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Thesis (M.S.)--West Virginia University, 2003.Title from document title page. Document formatted into pages; contains xi, 101 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 95-99).
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De, Wilde Els. "Attentional contrast during sequential judgments an explanation for the number-of-levels effect /." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0011080.
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Aloumi, Ahmad E. "The effect of colour contrast combinations on the simplicity and complexity of design." Thesis, Bournemouth University, 2013. http://eprints.bournemouth.ac.uk/20966/.
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A common goal for designers is to deliver an intentional message from the sender to the intended receivers via design. !e design can be constructed to be a crystal-clear and interesting model that viewers can easily and immediately understand. However, some designs are intricate, complex, and layered in detail, and these require more e"ort on the part of the viewer if they are to understand the design messages. During the design process, designers pass through several stages that a"ect the design outcome. One of these key stages is the colouring process. Colour has the power to make or break the design intention. In addition, colour can either add complexity to the design by the use of di"erent colour contrasts, or help simplify a complex design form. !is research investigates the e"ect of colour combinations on simple and complex design appearance, with regard to the e"ects of contrast when colours are juxtaposed in a design. !e aim of the research is to identify which colour contrast a"ects the simplicity and complexity of a design’s appearance. !e research demonstrates how design form could be evaluated di"erently in terms of the use of di"erent colour combinations. !e research uses applied experimental methods to analyze participant responses to colour combinations. It reveals the result of the study by describing the signs of simple and complex colour combinations and the e"ect of colour on di"erent designs. !e research also proposes methods for increasing or decreasing the level of complexity of a design solution by using di"erent colour combinations with their associated e"ects on the diversity of colour contrast. All of this information is used to create a design tool which will help designers and students to make colour choices which are more suited to the design solution.
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Parrott, Danielle Elizabeth. "Signal in the Noise? The Effect of Non-Invasive Brain Stimulation on Contrast Perception." Doctoral thesis, Università degli studi di Trento, 2020. http://hdl.handle.net/11572/269602.
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A longstanding question in studies of cortical stimulation has been how does stimulation affect brain functioning and cognition, and what are its mechanisms of action. Brain stimulation has been traditionally seen either as a disrupting intervention or as a procedure to enhance cortical excitability and promote improvement in various modality from motor to visual performance. In vision, several hypotheses have been proposed and many experimental paradigms have been used to study how transcranial magnetic stimulation (TMS) and direct current stimulation, particularly transcranial random noise stimulation (tRNS) affect visual discrimination. Psychophysical paradigms are particularly useful to measure visual performance, whereby a stimulus is progressively changed from easy to difficult to perceive it, and accuracy threshold can be measured by titrating the stimulus discriminability. Stimuli that vary in contrast are typically used to study low-level visual functions and it is well known that neurons within the early visual areas in the brain, and primarily V1, are tuned to stimuli involved in contrast discrimination. Here we used an orientation discrimination task to study changes in contrast detection by varying stimulus contrast across different levels (Experiment 1, Chapter 2). We used neuro-navigated single-pulse TMS at different intensities to determine whether behavioral
response changed linearly as a function of stimulus discriminability independently of TMSintensity, or whether TMS affected behavior depending on TMS intensity and contrast level. Moreover, we tested whether TMS had an effect selective for the field contralateral to stimulation or whether effects could be seen across the entire visual field. Single pulse TMS was delivered to left V1 while participants performed a 2-alternative forced choice orientation discrimination (OD) of one of two Gabor patches presented on either side of fixation at 5 contrast levels and 4 TMS intensities. Participants' performance on OD increased at all contrast levels in the right visual field (contralateral to stimulation) at 80% of phosphene thresholds (PT, individually measured at baseline). Furthermore, when TMS was delivered at 60% of PT, we found improved performance in the right visual field that
was selective for the medium contrast, while performance increased at the highest contrast irrespective of TMS intensity, in the field ipsilateral to stimulation, thus both visual fields were affected by TMS, albeit differently. Since the improvement effects might be explained as the result of added noise to the system that paradoxically improves performance for justbelow threshold stimuli (middle contrasts), in Experiments 1 and 2 (Chapter 3) we used transcranial random noise stimulation, a neuromodulation procedure known to enhance cortical excitability when delivered at high frequencies, to further test the hypothesis that
brain stimulation might work through a mechanism of stochastic resonance, whereby adding noise to a nonlinear system, the brain in our case, might paradoxically promote better performance by enhancing stimulus discriminability. This might happen only for selective stimulus intensities and stimulation strength. Based on previous successful work, we tested contrast discrimination changes as a function of four different tRNS low intensity levels of stimulation, and we found a decrease in performance selective for the condition with subthreshold stimuli and at .750 mA stimulation intensity. This result might indicate
that low intensity stimulation is not enough to promote enhancement of stimuli under the stochastic mechanism effect, thereby suggesting that higher ranges of stimulation are necessary to create the optimal conditions for improvement.
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Kogan, Vita. "The Effect of First Language Perception on the Discrimination of a Non-native Vowel Contrast: Investigating Individual Differences." Doctoral thesis, Universitat de Barcelona, 2020. http://hdl.handle.net/10803/668736.
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Adult language learners often experience difficulty acquiring a new sound system. Empirical studies have shown that native phonetic categories function as a filter that removes specific acoustic cues for non-native sounds and causes “a perceptual accent”. Not being able to perceive contrastive segment categories that do not exist in learner’s native language result in production problems and accented speech. Yet, some individuals are remarkably successful at the task of non- native perception. Such instances demonstrate that perceptual ability is a subject of high variability. Whereas native language (L1) background has been the focus of much second language acquisition research to explain such variability, little attention has been paid to the role of individual differences within the same L1 perception. This dissertation seeks to fill this gap and investigate how individual differences in native perception affect the degree of perceived dissimilarity between two members of a novel contrast that does not exist in learners’ L1. We argue that not only individuals with various L1s are equipped differently for the task of non-native perception, but also individuals with the same L1 vary in how their native phonological categories are represented in the perceptual space. Such variability is observable in measures of compactness of L1 phonetic categories, and its effects on non-native perception can be assessed by relating the degree of compactness to the perceived dissimilarity between novel contrasting sounds. We hypothesized that compact L1 categories give an initial advantage in distinguishing non-native contrasts.
Sixty-eight Spanish monolinguals participated in the present study. The degree of compactness of their native category /i/ was measured through a goodness-of-fit rating task, where participants listened to synthesized variants of the Spanish /i/ vowel (differing in F1, F2 or both) and rated them as either good or bad exemplars of their internal representation of the category /i/ on an intuitive scale. These ratings provided an individual /i/ compactness index for each participant that was related to the individual perceived dissimilarity score for the novel Russian contrast /i - ɨ/. The results obtained confirmed the hypothesis. Even though L1-based individual differences in perception were small, compactness of the L1 category /i/ contributed significantly to the participants’ ability to perceive the acoustic distance between the Russian /i/ and /ɨ/. These findings suggest that having more compact vowel categories might facilitate the process of category formation for unfamiliar sounds.Los estudiantes adultos de idiomas a menudo experimentan dificultades para adquirir un nuevo sistema de sonido. Los estudios empíricos han demostrado que las categorías fonéticas nativas funcionan como un filtro que elimina las señales acústicas específicas de los sonidos no nativos y causan "un acento perceptivo". La impossibilidad de percibir categorías segmentales contrastivas que no existen en el idioma nativo del aprendiz correctamente ocasiona problemas en la producción de los fonemas conducentes a la presencia de acento extranjero en el habla. Sin embargo, algunos individuos son capaces de percibir fonemas no-nativos con notable éxito. Tales casos demuestran la gran variabilidad entre sujetos en cuanto a su capacidad perceptiva para los sonidos del lenguaje. . Dicha variabilidad se ha investigado extensamente a través numerosos estudios que se han focalizado en el factor de la lengua nativa (L1) como la principal causa. . No obstante, se ha prestado poca atención al papel potencial de las diferencias individuales en la percepción de la L1. Esta tesis pretende abordar esta cuestión empírica investigando hasta qué punto las diferencias individuales entre sujetos en la percepción de su lengua nativa afectan el grado de disimilitud perceptiva entre los miembros de un nuevo contraste fonológico inexistente en la L1 de los aprendices. Nuestra hipótesis plantea la idea de que no sólo los individuosde primeras lenguas diferentes están preparados de diferente forma para la percepción de los sonidos de una segunda lengua, sino que también los individuos que comparten una misma L1 presentan variabilidad en cómo representan sus categorías fonológicas en su espacio perceptivo, y ello puede también tener consecuencias para la percepción de los sonidos de una lengua no nativa. Partimos de la base de que la variabilidad inter-sujetos en la percepción de las categorias fonológicas nativas es observable a partir de medidas del grado de compactación de las categorías fonéticas en la L1. Los efectos del grado de compactación sobre la percepción no nativa pueden evaluarse relacionando el grado de compactación de una categoría fonológica nativa con el grado de disimilitud perceptiva observada en la percepción de contrastes fonológicos al inicio del proceso de adquisción de una nueva lengua. . Nuestra hipótesis es que aquellos individuos que presentan un mayor grado de compactación de las categorías fonológicas de la L1 obtienen una ventaja inicial en la distinción de contrastes fonológicos no nativos. Sesenta y ocho monolingües de español participaron en el presente estudio. El grado de compactación de su categoría nativa /i/ se midió a través de una tarea perceptiva donde los participantes escucharon variantes sintetizadas de la vocal española /i/ que presentaban diferèncias equidistantes en F1, F2 o ambos a la vez calificaron en una escala intuitiva como buenos o malos ejemplares de su representación interna de la categoría vocálica /i/. Esta tarea nos proporcionó un índice individual del grado de compactación de la vocal /i/ para cada participante, que relacionamos con la medida de disimilitud perceptiva individual que cada participante obtuvo para el contraste del ruso /i - ɨ/. Los resultados obtenidos confirmaron la hipótesis. Aunque las diferencias individuales en la percepción de la vocal /i/ del español observadas fueron de pequeña magnitud, el grado de compactación de /i/ contribuyó significativamente a la capacidad de los participantes de percibir la distancia acústica entre los fonemas vocálicos del ruso /i/ y /ɨ/. Estos resultados sugieren que tener categorías de vocales más compactas podría facilitar el proceso de formación de categorías fonológicas en la adquisición inicial de una nueva lengua.
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Skinner, Fiona K. "Dopamine and visual function in schizophrenia : a psychophysical investigation using the tilt after-effect and contrast sensitivity tests." Thesis, University of Aberdeen, 1994. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU068528.
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The study used a non-invasive technique, the Tilt Aftereffect (TAE) test, to investigate the visual changes influenced by dopamine (DA) in schizophrenia. One-third of forty five schizophrenic patients could not complete the TAE test and this group was found to have impaired sustained attention and to have different demographic and clinical characteristics from the schizophrenic patients who could complete the TAE test. TAE changes were found only in response to DA changes brought about by altering neuroleptic levels, e.g. 'before' compared with 'after' a depot injection. These changes were only found when gratings of 2 c/d were used and not for 10 c/d. No illness or drug effect was found using the TAE test. A similarity in the pattern of change over time was found for the TAE test using 2 c/d gratings and the peak spatial frequency (SF) from the Contrast Sensitivity (CS) test in response to changes in levels of DA. A decrease in DA caused a shift of the CS peak to lower SFs, with a decrease in sensitivity for mid to high SFs (3 - 10 c/d) and an increase in sensitivity for low SFs (0.5, 1 c/d). The findings suggest that both the TAE and CS tests are influenced by DA and that lateral inhibition alone cannot explain the production of the TAE since the influence of the orientation of the adapting gratings on the size of the TAE indicates that an adaptation process is involved. It is suggested that the transient system, which is sensitive to low spatial and high temporal frequencies, may be selectively affected by DA changes.
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Holroyd, Wayne. "The effect of simultaneous application of contrast temperature therapy and intermittent compression on recovery following exercise induced muscle damage." Master's thesis, University of Cape Town, 2011. http://hdl.handle.net/11427/11439.
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Objective: To determine the effects of the simultaneous application of contrast temperature therapy with intermittent compression as a recovery strategy for the quadriceps muscle following exercise induced muscle damage in moderately active adult males.
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Diamond, Mark R. "The effect of saccades on visual sensitivity and time perception." University of Western Australia. School of Psychology, 2003. http://theses.library.uwa.edu.au/adt-WU2003.0038.
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Considerable evidence indicates that visual sensitivity is reduced during saccadic eye movement. A central question has been whether saccadic suppression results from a non-visual central signal, or whether the obligate image motion that accompanies saccades is itself sufficient to mask vision. In the first of a series of experiments described here, the visual and non-visual effects of saccades were distinguished by measuring contrast sensitivity to luminance modulated low spatial frequency gratings, at 17 cd·m¯² and 0.17 cd·m¯², in saccade conditions and in conditions in which saccade-like image motion was produced by the rotation of a mirror but when observers’ eyes were kept still. The time course of suppression was examined by making measurements from well before image motion began until well after it had ended. A tenfold decrease in contrast sensitivity was found for luminance-modulated gratings with saccades, but little suppression was found with simulated saccades. Adding high contrast noise to the visual display increased the magnitude and the duration of the suppression during simulated saccades but had little effect on suppression produced by real saccades. At lower luminance, suppression was found to be reduced, and its course shallower than at higher luminance. Simulated saccades produced shallower suppression over a longer time course at both higher and lower luminance. In a second experiment the time course of contrast sensitivity to chromatically modulated gratings, at 17 cd·m¯², was examined. No suppression was found; rather there was some evidence of an enhancement of sensitivity, both before and after saccades, relative to fixation conditions. Differences in the effects of real and simulated saccades in the magnitude and time course of sensitivity loss with luminance modulated gratings suggest that saccadic suppression has an extraretinal component that acts on the magnocellular system; the pattern of enhancement found in the later experiment suggests a selective favouring of the parvocellular system both immediately prior to and immediately after saccades. The possibility that the degree of enhancement in sensitivity varies across the visual field was examined using spatially localized stimuli (either high spatial frequency chromatically modulated gratings or letter combinations). Sensitivity was found to decrease at the initial fixation point during the 75 ms prior to saccadic onset and simultaneously to improve at the saccadic target. In the immediate post-saccadic period, sensitivity at the saccadic target was found to exceed that which had been manifest at the initial fixation point prior to saccades, suggesting that post-saccadic enhancement may improve the temporal contrast between one fixation and the next. The final experiments investigated the possibility that our sense of continuity across saccades (as opposed to stability) is influenced by saccade-induced errors in locating events in time. The results of these experiments suggest that saccades can result in errors in judging (a) the time at which external events occur relative to saccadic onset, (b) the temporal order of visual events, and (c) the magnitude of temporal intervals. It is concluded that apparent time is generally foreshortened prior to saccades. This might be due to selective suppression of magnocellular activity and might function to hide saccades and their effects from our awareness. A speculative synthesis is presented based on the idea that recurrent feedback between the neocortical and cortical structures on the one hand, and the thalamic nuclei on the other, has special importance for perception around the time of saccades
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Fonseca, Cassiane Dezoti da. "Nefropatia induzida por contraste iodado e o diabetes mellitus: modelo experimental em ratos." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/7/7139/tde-12092014-121109/.
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A nefropatia induzida por contraste (NIC) é uma lesão renal aguda (LRA) tóxica, que consiste em vasoconstrição intra-renal, toxicidade tubular direta com liberação de espécies reativas de oxigênio (EROs). A NIC está diretamente associada a doenças crônicas que comprometem a oxigenação da região da medula renal, como a disfunção renal preexistente, o Diabetes Mellitus (DM) e insuficiência cardíaca congestiva. Esse estudo investigou os mecanismos fisiopatológicos que caracterizam a NIC em ratos diabéticos. Foram utilizados ratos Wistar, adultos e machos. No protocolo DM foi realizada a nefrectomia unilateral esquerda (Nefré) no 1º dia, para potencializar o efeito tóxico da hiperglicemia crônica no rim. O DM foi induzido pela administração intravenosa (i.v.) de 65 mg/kg de estreptozotocina (STZ, diluída com citrato) no 20º dia, e o contraste iodado (CI) ioxitalamato de meglumina, 6 ml/kg, foi administrado (intraperitoneal, i.p.) no 85º dia. Foram realizados os seguintes grupos: Citrato (controle); Nefré+Citrato; DM; Nefré+DM; DM+CI; Nefré+DM+CI. Foram avaliados parâmetros fisiológicos (ingestão de ração e água, peso, glicemia capilar, peso do rim e peso relativo do rim); a albuminúria (método de imunodifusão), a função renal (FR) (clearance de creatinina, método de Jaffé), a lesão oxidativa (peróxidos urinários-PU, FOX-2; substâncias reativas com o ácido tiobarbitúrico-TBARS, tióis no tecido renal) e análise histológica renal (lesão tubulointersticial). Observou-se que os grupos diabéticos apresentaram polifagia, polidipsia, hiperglicemia e redução do peso corporal (p<0,05), além de redução do clearance de creatinina com elevação de PU e TBARS, manutenção de tióis e elevação da albuminúria. O tratamento com CI nos animais diabéticos determinou redução da FR, elevação dos PU e TBARS e redução dos tióis. Quanto à histologia renal, demonstrou-se que apenas o grupo Nefré+DM+CI apresentou lesão tubulointersticial. Os achados dessa investigação confirmaram o efeito tóxico do CI dose única sobre a função renal de ratos com hiperglicemia crônica, pressupondo que o DM seja fator de risco para essa nefropatia.Contrast-Induced Nephropathy (CIN) is a toxic acute kidney injury (AKI) that consists in intrarenal vasoconstriction, direct tubular toxicity with generation of reactive oxygen species (ROS). The CIN is associated with the decreased tissue oxygen tension in renal medula in preexisting renal dysfunction, Diabetes Mellitus (DM) and congestive heart failure. This study investigated the pathophysiologic mechanisms in the CIN in diabetic rats. Adult, male, Wistar rats were used. It was performed left uninephrectomy (Nx) on the 1st day in the DM group to potentialize the toxic effect of the chronic hyperglycemia. The DM was induced by a single dose of intravenous streptozotocin (65mg/kg i.v.) in sodium citrate buffer, on the 20th day and the iodine contrast (IC) meglumine ioxithalamate 6 ml/kg was administrated (intraperitoneal, i.p.) on the 85th day. Animals were divided into the following groups: Citrate (control); Nx+Citrate; DM; Nx+DM; DM+IC; Nx+DM+IC. Physiological parameters (water and food intake, body weight, blood glucose, kidney weight and relative kidney weight); renal function (creatinine clearance, Jaffé method); urine albumin (imunodifusion method); oxidative injury (urinary peroxides, FOX-2, tiobarbituric acid reactive substances-TBARS and thiols in renal tissue) and kidney histological analysis (tubulointerstitial injury) were evaluated. In the diabetic groups, polyphagia, polydipsia, increased blood glucose and reduced body weight were observed (p<0.05). The relative kidney weight was increased in the Nx and IC animals (p<0.05). The renal function was reduced; urinary peroxides and TBARS were increased in the diabetic and IC animals. The decrease in thiols levels in the diabetic and IC groups demonstrated the endogenous substrate consumption. The Nx animals that received IC presented tubular cells vacuolization and edema with moderate injury. The data has described the pathophysiology of CIN in diabetic rats involving oxidative injury that resulted of association of chronic high blood glucose and IC toxicity, suggesting that DM can be pointed out as a risk factor for CIN.
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Ekure, Edgar. "Global summation of radial frequency patterns and the effect of sudden onset glare on shape discrimination." Thesis, NSUWorks, 2014. https://nsuworks.nova.edu/hpd_opt_stuetd/10.
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ABSTRACT Global summation of radial frequency patterns and the effect of sudden onset glare on shape discrimination The purpose of this study was to provide evidence of global pooling around the circumference of the Radial frequency (RF) pattern, and to study the effect of sudden onset glare on shape discrimination. The RF stimuli were generated by the amplitude modulation of the radius of a circle which deforms them from circularity, while the cross sectional luminance profile was the fourth derivative of Gaussians (D4). The amplitude of the stimuli determines how distinct the pattern is and thus measures the degree of sensitivity while the radial frequency determines the number of lobes the pattern has. In the first part of the study, whole RF patterns (RF3 to RF16) and open component fractions (0.125, 0.25, 0.5, 0.75), which are incomplete sectors of the whole, were tested against their respective reference unmodulated patterns. Subjects were tasked with discriminating minute deviations from their reference patterns. In the second part of the study, high contrast (20 X detection threshold) RF3 and RF4 contours and equivalent low contrast (5 X detection threshold) RF3 and RF4 contours were used as stimuli. Shape discrimination threshold for the high contrast target was determined with and without sudden onset glare. The result of the first part of the study showed that threshold decreased significantly as larger component RF patterns were tested (p < 0.05). The decrease could not be accounted for by the probabilistic sampling of local filters (probability summation). The result of the second part of the study showed that shape discrimination threshold increased with sudden onset glare. The increase was even more pronounced with lower mean luminance and when smaller fractions of the contours were tested. Shape discrimination threshold was significantly higher with high contrast contours in the presence of glare than equivalent low contrast contours, indicating that the veiling luminance model alone could not account for a decrease in visual performance in this shape discrimination task.
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Rear, Roger. "The effect of remote ischaemic preconditioning on contrast induced nephropathy in the clinical setting of coronary angiography and percutaneous coronary intervention." Thesis, University College London (University of London), 2017. http://discovery.ucl.ac.uk/10034058/.
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Contrast Induced Nephropathy (CIN) is a common and serious iatrogenic complication resulting from the use of intravascular iodinated contrast media in routine investigations such as coronary angiography. Patients with impaired renal function are particularly at risk of CIN and a number of well recognised clinical and procedural risk factors exist which can be integrated into several risk scoring models. The principal pathophysiological mechanism for CIN consists of a renal ischaemia reperfusion injury (IRI) induced by the physico-chemical properties of contrast media in susceptible individuals. Remote ischaemic preconditioning (RIPC) is a novel intervention that involves cycles of non-injurious limb ischaemia, achieved via repeated inflation and deflation of a blood pressure cuff, prior to the onset of injurious organ ischaemia. A number of clinical studies have demonstrated that RIPC safely confers a short term protective effect against subsequent injurious IRI at a remote site such as the heart or kidney. The clinical trial ERICCIN, presented within this manuscript, was a multi centre double-blinded randomised controlled study investigating whether RIPC could safely reduce the incidence of CIN in 100 patients with impaired renal function undergoing elective or emergency coronary angiography or PCI at three cardiac centres in south east England in 2015/16. Both study and sham groups received optimal prophylactic measures against CIN. The RIPC/sham procedure was delivered by a novel automated device developed specifically for the study, with RIPC therapy being well tolerated and no complications were reported. The primary outcome measure was reduction in the incidence of CIN at 48 hours, defined as serum creatinine elevation >25% or 0.5g/dl (44μmol/l) above baseline. The secondary outcome measures included changes from baseline in serum serum creatinine/eGFR, urine albumi at 48 hours and at 3 months as well as cardio-renal endpoints. The study was inadvertently underpowered and no difference in primary or secondary outcome measures was demonstrated between RIPC and sham groups, although a trend towards benefit was seen in the RIPC group. Subgroup analysis suggested significant abrogation in acute microalbuminuria in participants with pre-exisiting heart failure receiving RIPC, although the small number of participants meant no conclusions could be drawn this may be hypothesis forming for future studies. The study included a comprehansive audit cycle, local education programme and participant feedback group meetings which are presented withtin the manuscript. The study mandated 100% compliance with optimal prophylactic stategies against CIN resulting in significantly reduced incidence of CIN from 15% to 5%, which was an unexpected but welcome finding which justifies full implementation of current clinical guidance in this field of practice.
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Charbonnel, Lionel. "La hiérarchie des normes conventionnelles : contribution à l’analyse normativiste du contrat." Thesis, Avignon, 2010. http://www.theses.fr/2010AVIG2023/document.
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La hiérarchie des normes est une notion commune du langage juridique. Les conventions, à l’instar de la Constitution à l’égard de la loi, peuvent-elle entretenir entre elles des relations hiérarchiques ? Trois éléments feraient obstacle à cette hypothèse. L’effet relatif des conventions, l’identité de nature juridique de ces actes et, enfin, le fait que les conventions ne soient pas des règles de Droit mais des actes d’exécution du droit.Lever un à un ces obstacles qui ne sont pas rédhibitoires et démontrer que le contrat est une règle de Droit, autorise alors à admettre théoriquement cette hypothèse. L’étude du droit positif permet ensuite de confirmer que des conventions peuvent entretenir des rapports hiérarchiques. Tel est le cas du contrat de société à l’égard des conventions de la société contractante ou bien encore du mandat à l’égard du contrat projeté.Il est alors possible d’étudier les conditions dans lesquelles un lien de nature hiérarchique peut apparaître. Les conditions préalables à cette mise en ordre supposent une pluralité d’actes et la nature conventionnelle de ceux-ci. Les « éléments constitutifs » du lien hiérarchique supposent eux que la convention qui occupe la place de norme supérieure soit impérative à l’égard des parties à la seconde conventionThe hierarchy of norms is a common notion of juridical language. Can contracts, like the Constitution regarding law, organize into a hierarchy? Three elements would put an obstacle in the way of this assumption. The relative effect of contracts, the juridical identity of theses acts and, finally, the fact that contracts are not rules of law but acts of law enforcement.Raising these obstacles one by one, obstacles that are not totally unacceptable, and demonstrating that the contract is a rule of law, allows then to theoretically admit this possibility. The study of substantive law confirms afterwards that cont can be organized into a hierarchy. This is the case of the society contract regarding the conventions of the contracting society, and of the mandate with the contract that is planned.It is then possible to study the conditions under which a hierarchical link can appear. The prerequisites for this hierarchical organization require a plurality of acts and their contractual nature. The "making up elements" of the hierarchical link are based on the assumption that the contract that holds the higher norm is with regard to the parties of the second contract
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Webber, Emily S. "Reward Comparison in the Striatum." Bowling Green State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1370269518.
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Kabir, Amin. "Phase coherent photorefractive effect in II-VI semiconductor quantum wells and its application for optical coherence imaging." University of Cincinnati / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1282315981.
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Mathias, Amber R. "The Effect of Bioptic Telescopic Spectacles Use on Sign Identification, Velocity, and Lane Deviation in a Driving Simulator with Central Vision Impairment." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu152303259493087.
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Rana, Omar. "The effect of insulin-induced hypoglycaemia on myocardial blood flow reserve in patients with Type 1 Diabetes and healthy humans : a study using myocardial contrast echocardiography." Thesis, University of Southampton, 2011. https://eprints.soton.ac.uk/362525/.
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Background: Hypoglycaemia is associated with increased cardiovascular mortality (CVM) but the reason for this is poorly understood. We tested the hypothesis that the myocardial blood flow reserve (MFBR) is decreased during hypoglycaemia using myocardial contrast echo cardiography (MCE) in patients with type 1 diabetes mellitus (DM) and in healthy controls. Methods and Results: Twenty-eight volunteers with DM (patients with and without MVD) and 19 controls underwent hyperinsulinemic clamps with maintained sequential hyperinsulinemic euglycaemia (HE, plasma glucose 90 mg/dl, 5.0 mmollL) followed by hyperinsulinemic hypoglycaemia (HH, plasma glucose 50 mg/dl, 2.8 mmollL) for 60 minutes each. Low-power real-time MCE was performed with flash impulse imaging using low-dose dipyridamole stress, at baseline, and during HE and HH. In control subjects MBFR increased during HE by 0.57 units (22%) above baseline, (B coefficient 0.57, 95%CI 0.38, 0.75, p
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Bergström, Fredrik. "Hur människors begrepp om urbana platser relaterar till bedömning av platsernas estetik och mikroklimat." Thesis, Linköping University, Department of Computer and Information Science, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-2322.
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The objective of this study was to uncover what aspects of urban plazas and parks that are most important for users’ evaluations of places’ aesthetics and microclimate (the characteristic climate for a limited space). This was done by investigating people’s general ideas of plazas and parks (the prototypical concepts) and compare these with place users’ descriptions of four specific places. Interviews with two groups (31 and 24 persons respectively) were carried out in order to collect this information. Aspects commonly mentioned in the descriptions, but not included in the prototype, were considered salient and schema-irrelevant (perceived as outstanding but not needed as a defining attribute of the place). This part of the result was related to evaluations of aesthetics and microclimate of the specific places, as well as to subjects’ explanations of some of these evaluations. Evaluations were collected in 716 questionnaires and 1115 on-site interviews, and the explanations in the 24 persons interview concerning specific places. The results indicate that for urban places to be emotionally appreciated they have to manifest some kind of effect of contrast, i.e. they have to embrace some salient schema-irrelevant aspect outstanding enough to work as a centre of the total experience of the place. Furthermore, the results indicate that a separation between emotional and practical aspects of place experiences is needed. In view of that, for urban places to be practically useful, they have to have a prototypical character. For a plaza to be prototypical, it has to be experienced as an enclosed and mainly hard-grounded open square, with good opportunities for commerce and social life. A park has to be green and be able to house a range of activities such as relaxing, picnics and walking.
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Fucini, Elisabeth [Verfasser], Ernst J. [Akademischer Betreuer] Rummeny, and Konstantin [Akademischer Betreuer] Holzapfel. "The Effect of MR Contrast Agents on the Viability and Differentiation Capacity of Human Mesenchymal Stem Cells / Elisabeth Fucini. Gutachter: Konstantin Holzapfel ; Ernst J. Rummeny. Betreuer: Ernst J. Rummeny." München : Universitätsbibliothek der TU München, 2013. http://d-nb.info/1038050642/34.
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Sua, Mehmet. "Les effets des réseaux de distribution." Thesis, Montpellier 1, 2010. http://www.theses.fr/2010MON10064.
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L'analyse de la dimension collective des réseaux de distribution en droit turc permet de constater concrètement les effets juridiques induits entre les membres de réseau par l'entrelacement des contrats bilatéraux. Il est important de relever que le réseau n'est pas constitué par une simple addition de contrats mais par une composition de contrats dont leur entrelacement produit des effets juridiques à l'égard de tous les contractants. Cette recherche s'applique à mettre en lumière jusqu'où un réseau peut développer des obligations et des responsabilités pour ses membres et tend à systématiser les règles générales de réseau qui peuvent organiser ces effets induits tout en respectant les limites du droit commun des contrats. En l'absence d'une stipulation contractuelle, les règles de réseau pouvant être induites à la charge des adhérents sont très réduites par rapport à celles induites à la charge du promoteur, puisque les adhérents ne possèdent pas d'un pouvoir de direction de réseau comparable à celui du promoteur. D'une part, les adhérents du même réseau ne peuvent pas agir dans leur fonction de distributeur comme s'il n'appartenait pas au même réseau, en d'autres termes, chaque adhérent a le devoir de prendre en considération les autres adhérents dans l'accomplissement de ses obligations, dès qu'il s'agit des obligations dont l'inexécution affecte l'activité commerciale d'autres adhérents ou l'image commune du réseau, d'autre part, en tant que le fondateur et le directeur permanent d'un système contractuel, le promoteur a l'obligation d'assurer la cohérence du réseau et la cohésion du réseauThe analysis of the collective dimension of distribution networks in Turkish law reveals to observe in concrete the legal effects induced between the network members by the interlacing of bilateral contracts. It is important to note that the network is not formed by simple addition of contracts but with interlacing of contracts that produce legal effects for all contractors. This research applies to highlight how far a network can develop responsibilities and obligations to its members and aims to systematize the general rules of network which can organize these induced effects while respecting the limits of the law of contract. In the absence of a contractual provision, the network rules can be induced at the expense of the adherents are very small compared to those induced at the expense of the promoter, since the adherents do not have the power of directing the network comparable to the promoter's. On the one hand, adherents of the same network cannot act in their function as distributor as if he does not belong to the same network, in other words, each member has a duty to consider the other adherents in the accomplishment of its obligations, since it is about obligations where the non-execution affects the business of other members or the common image of the network, on the other hand, being the founder and permanent director of a contractual system, the promoter has the obligation to assure the coherence and cohesion of the network
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Pak, Sim Tess. "The moderating effects of causality orientations on psychological contract breach outcome relationship /." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B38587919.
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Chu, Huu Thang. "Effets du contrat d'entreprise : comparaison franco-vietnamienne." Thesis, Paris 2, 2017. http://www.theses.fr/2017PA020033/document.
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La thèse examine la comparaison des effets du contrat d’entreprise en droit français et en droit vietnamien. Au sein des contrats spéciaux, dans un monde d’économie de services accrue, le contrat d’entreprise joue désormais un rôle majeur. Ses multiples facettes pourraient d’emblée permettre de dresser une liste de métiers. Elle serait haute en couleur, puisque la plupart des prestations de services peuvent se couler dans le moule juridique du contrat d’entreprise, pour le quel se trouvent concernés artisans,artistes, professions libérales, etc. Synallagmatique, le contrat d’entreprise engendre des obligations réciproques à la charge de l’entrepreneur et du maître de l’ouvrage. Elle a permis de mettre en évidence les obligations qui constituent le droit commun du louage d’ouvrage, et de s’apercevoir que les obligations nées du contrat d’entreprise ainsi que ses effets revêtent des contours spécifiques qui s’expliquent par particularités de la convention. Ces particularités sont indéniables s’agissant des obligations principales et accessoires de l’entrepreneur à l’égard du maître de l’ouvrage et à l’inverse. Ces deux parties devraient être sanctionnées pour l’inexécution des obligations contractuelles et être exonérées de la responsabilité en justifiant les causes d’exonération. L’étude comparative de ces particularités en droit français et en droit vietnamien permettra de constater les similitudes et les divergences entre les deux systèmes juridiques. Les deux pays sont proches sur le plan juridique. Ainsi, la conclusion qui s’en dégage est que certaines dispositions du droit français pourraient utilement inspirer les législateurs vietnamiens et vice versaThe thesis examines the comparison of the effects of the contract of enterprise in Vietnamese law and French law. Within the special contracts, in a world of greater economy of services, the contract of enterprise plays from now on a major role with various operations. It would be with a ruddy complexion, because most of the services can steal into the legal mold of the contract of enterprise, thus that are concerned craftsmen, artists, medical services, liberal professions, etc. Synallagmatic, the contract of enterprise engenders mutual obligations chargeable to the contractor and the owner. The study allowed to point out the obligations that constitute the common rules of the contract of enterprise and, to notice that the obligations following the contract of enterprise are specific because of the particular aspects of this agreement.The particularities are undeniable with respect to the main and secondary obligations of the contractor towards his owner and on the contrary. Both parties should be sanctioned by the non-fulfillment of the contractual obligations and to be exempted from the responsibility by justifying the causes of exemption. Comparative studies of these particularities in French law and in Vietnamese law will allow to notice the similarities and the differences between both legal systems. The two countries are close on the legal plan. Thus, the conclusion that emerges is that certain provisions of the French law could usefully inspire the Vietnamese legislators and vice versa
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Samson, Deborah Christine Veronica. "Contrast effects in fear." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/31484.
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The purpose of this research was to determine if fear is subject to the contrast effect that pervades psychophysical and other psychological phenomena. A contrast is said to occur when the judgement of a target stimulus is inversely related to the stimulus that preceded it; hence, it was expected that the response to a fearful stimulus should be inversely related to the response made to the preceding fear stimulus.
The occurrence and nature of contrast effects were investigated in two laboratory studies of fearful people. In the first experiment, sixty-five university students were exposed on separate occasions to two fearful stimuli (spiders and snakes). The first exposure session was manipulated so that experimental groups differed in the amount of fear evoked by the stimulus (high fear, moderate fear, and low fear). Exposure to the second animal was designed to produce a moderate level of fear in all subjects. During exposure to the animals, measures of subjective fear and heart rate were taken. Results suggested that a contrast effect had occurred. Compared to a control group of subjects who experienced moderate fear on two occasions, subjects who had a high fear response to the initial stimulus showed a decrease in fear to the second stimulus. Subjects who had a low fear response to the initial stimulus showed an increase in fear to the second stimulus. This increase in fear was evident in subjective and physiological indices. None of the effects was evident when participants were reassessed one week later, suggesting that the fear contrast effect is transient.
Four theories were evaluated with regard to their ability to
account for the above findings. None of the theories could sufficiently explain the results, suggesting that a combination of at least two is necessary.
The purpose of the second experiment was to replicate the above findings, and to investigate three additional aspects. These included: a) the participant's awareness of contrast effects, b) the role of perceived similarity of the context and target stimuli, and c) the interaction between mood states and prior context. A 2 by 3 factorial design was utilized with prior context (high fear, low fear) as the first factor, and mood induction (happy, sad and no mood induction) as the second factor. Subjective fear and heart rate were recorded during exposures to the feared stimuli. In addition, perceived similarity of the target and context was examined using three questionnaires, each assessing a different dimension of similarity. Awareness of contrasts was assessed with a post-experimental questionnaire. In the absence of mood induction, contrast effects occurred as they had in the first experiment. In the conditions involving mood induction, an interaction was evident. A happy mood blocked a low-to-moderate fear contrast, and a sad mood blocked a high-to-moderate fear contrast. Contrary to expectations, none of the similarity questionnaires was related to the magnitude of the contrast effect. Finally, subjects did not appear to be aware of their own experience of a fear contrast.Arts, Faculty of
Psychology, Department of
Graduate
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Carney, Melody Noelle. "The Impact of the Optical Phenomena of Color Adjustment Potential and Kubelka-Munk Layering of Dental Composite Resins on Modern Esthetic Dentistry." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1429403504.
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Ni, Zhifang. "Contrast effects on sequence assessments." Thesis, London School of Economics and Political Science (University of London), 2010. http://etheses.lse.ac.uk/267/.
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Loewenstein and his colleagues found divergent preferences for outcomes assessed in isolation versus those embedded in a sequence, i.e. discounting isolated future outcomes versus preferences for increasing and constant sequences. They also found long intervals (i.e. the difference between time delays) rather than long time delays (i.e. the temporal distance from the present) had a detrimental effect on preference for improvement. This thesis proposes a descriptive model of sequence preferences, namely the contrasts model, which acknowledges the difference between interval and delay. The idea is that delay and interval are two different kinds of variables. Delay is non-relational and describes characteristics of individual outcomes, whereas interval is relational and describes characteristics of outcomes in relation to one another. Built on this idea, the contrasts model assumes that the value of a sequence consists of a non-relational part (the endowment value), which is a function of delay and nominal value of the component outcomes and a relational part (the contrast value), which is a function of the signed value difference between the outcomes, their interval and domain relatedness (i.e. whether or not the outcomes share the same domain). Delay and interval influence the endowment and the contrast respectively. Empirical investigations provide evidence for the contrasts model. Decision makers are capable of distinguishing between influences of delay and interval even when the two coincide and exert conflicting influences. Experiments using both money and non-monetary outcomes also show that preferences for improvement can be made more pronounced by shortening intervals and/or enhancing relatedness between the outcomes.
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Massendari, Delphine. "La programmation des saccades oculaires chez l'homme : rôle et décours temporel des traitements visuels élémentaires." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM3023/document.
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Notre environnement visuel est riche en lumière, couleurs, traits, textures et formes. Pour appréhender cette richesse, nous déplaçons nos yeux tous les quarts de seconde à l'aide de mouvements très rapides appelés saccades. Une telle vision dite active a fait l’objet de multiples recherches, mais les interactions entre les systèmes visuel et oculomoteur ne sont pas clairement établies. Cette thèse vise à préciser ces interactions en étudiant si les délais temporels associés au traitement d'informations visuelles de plus en plus élaborées contraignent où et quand nos yeux bougent. Trois séries d'études comportementales menées chez l'homme et utilisant des paradigmes novateurs ont été réalisées. Elles nous ont permis de mettre en évidence que le traitement des contrastes d'orientation, tout comme le traitement des contrastes de luminance sont intégrés par le système saccadique. En effet, un stimulus (distracteur) différant d'un fond texturé par sa luminance ou son orientation dévie le regard de sa cible dans la même mesure, et ce, quelle que soit la latence des saccades. Néanmoins, le contraste de luminance conserve un rôle prédominant. Premièrement, il conduit au déclenchement plus précoce des saccades en comparaison avec le contraste d’orientation. Deuxièmement, dès lors qu'il entre en compétition avec des informations plus élaborées comme le contour, il suffit à déterminer la métrique des saccades. Ainsi, en accord avec l'architecture des systèmes visuel et oculomoteur, les traitements visuels influencent la programmation des saccades de manière ordonnéeOur environment is rich in light, color, features, textures, and shapes. To extract this information, we move our eyes four times per second with rapid eye movements called saccades. This so-called active vision has been studied extensively, but the interactions between the visual and oculomotor systems have not been fully characterized yet. This thesis aims to clarify these interactions by investigating whether the delays in processing visual information of increasing complexity determine where and when our eyes move. The present work focuses on three types of basic visual processing for which the neural substrates are well established and predict a specific order in the programming of saccades at the level of the superior colliculus. We conducted three series of behavioral studies with human participants using novel experimental paradigms. These studies showed that orientation-contrast processing as well as early luminance-contrast processing are integrated in the saccadic system to the same extent. When aiming for a target stimulus, the eyes deviate toward a distractor stimulus in equal measure, irrespective of whether the distractor differed in luminance or orientation from a texture background and irrespective of saccade latency. However, the role of luminance contrast remains dominant. Firstly, luminance contrast triggers faster saccades than orientation contrast. Secondly, when luminance contrast competes with more complex information such as contour, solely luminance contrast determines saccade metrics. Therefore, visual processes influence saccade programming in a specific order that is consistent with the architecture of the visual and oculomotor systems
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Christensen, My, and Johanna Pihlgren. "Typografiska riktlinjer och textframställning för smartphones." Thesis, Högskolan Dalarna, Grafisk teknologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:du-10724.
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Idag använder allt fler människor sina smartphones för att surfa och använda tjänster online. Detta innebär att en stor del text läses på små skärmar. Detta arbete handlar om hur text bäst utformas och struktureras för att enklast kunna läsas och uppfattas på en mobilskärm. Faktorer som berörs är typgrad, ljusrum, textlängd, teckensnittsklass, radlängd, bild i text och kontrastverkan. Arbetet utgår från en normativ, svensk person utan funktionsnedsättningar. Arbetet är grundat på litteratur, egna analyser, intervjuer med branschfolk, enkätundersökning och test med fokusgrupp. Resultatet blev att en text på smartphone bäst utformas med flera styckesindelningar i form av blankrader, med bilder där bilden tillför något i informativt syfte och textlängd baserat på ämneskategori. Bilden bör sättas ovanför brödtexten. Längre texter ska sättas med scrollfunktion. Kontrast har stor betydelse på mobiltelefoner, texter går bra att läsa även när de är satta negativt. Teckensnittsklass är enligt resultatet av denna rapport inte av betydelse. Både seriff och sanserif kan läsas utan problem på smartphones. Typgraden bör förstoras något i förhållande till telefonens default-inställningar. På grund av att text på skärm inte stödjer avstavningar rekommenderas korta ord där det är möjligt för att förhindra en allt för hackig högerkant.This research focuses on the issue of how to best structure text on a Smartphone screen. The factors involved in this research are text size, white space, text and line lengths, serif and sans serif fonts, pictures in text and contrast. The methodology of our research is based on a normative Swedish able-bodied person, as well as on relevant literature, personal analyses, interviews with people in the trade, an online survey, and a test performed with a focus group. The results are that a text written for Smartphones is best structured with: several paragraph divisions made with blank lines, with pictures where the picture has an informational purpose, and text length based on category of subject. The picture should be placed above the body text. Longer texts should be set with a scroll-function. Contrast is of great importance on mobile phones as texts can be read properly even when set in negative. In addition, using serif or sans serif is of no importance. According to the results both serif and sans serif can be read without difficulties on a Smartphone. Text size should be slightly enlarged in relation to the default settings on the mobile device. Since word division is not supported on screen, short words are recommended when possible to prevent a highly uneven right end.
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Pak, Sim Tess, and 白嬋. "The moderating effects of causality orientations on psychological contract breach: outcome relationship." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B38587919.
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Berne, de la Calle Cédric. "Le contentieux de la résolution du contrat au regard de l'article 1184 du Code civil : éléments pour une stratégie du créancier." Thesis, Aix-Marseille, 2014. http://www.theses.fr/2014AIXM1027.
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La stratégie du créancier face à l'inexécution est une réalité masquée par les théories, elle est tacite dans les analyses. Les éléments qui la composent sont étudiés tour à tour de façon à découvrir une institution qui est composée de mécanismes interdépendants ayant chacun son propre ressort. À partir de l'article 1184 du Code civil, il a fallu saisir l'esprit de la résolution, des qualifications qu'elle comprend, expressément et tacitement, dans l'optique de vérifier les connaissances présentés comme certaines afin de projeter l'institution dans une perspective d'avenir.À travers huit thématiques constitutives de la résolution, il est question d'opérer un tri dans les connaissances relatives au domaine de l'action, à la disqualification de la force majeure, à l'inexécution du contrat par le débiteur dûment constatée par une mise en demeure. Le juge une fois saisi, le créancier bénéficie ainsi de l'option entre résolution ou exécution forcée conférée par l'article 1184 alinéa 2, amenant au caractère judiciaire - fort discuté - de l'action. Enfin, la résolution produit des effets apparents sur le contrat : la rétroactivité mais surtout des effets caractéristiques : l'extinction et les restitutions qui sont issues de la décision judiciaire de résolution.Si le concept de résolution a été étudié à travers son fondement, son histoire ou encore ses formes diverses, il restait à explorer l'envers de cette théorie dans une relecture critique rappelant sa fonction première : permettre au créancier de protéger le contrat face au phénomène d'inexécutionCreditor's strategy in case of breach of contract is often avoided because of full theories.It could be described as a tacit phenomenon. Elements of judicial dissolution are studied in a way to discover a legal institution made by independent mechanisms which each have their own spring. Starting with article 1184 of French Civil Code, the aim of the study was to grasp the spirit of "judicial dissolution" of contract, also the legal institutions it contains, formally or tacitly, checking all the law doctrinal knowledge, supposed to be certain and proposing a perspective for this particular judicial termination of contract.Judicial dissolution composed of eight themes is a study trying to share into a mass knowledge relative to the action's area, the fortuitous event (irresistible force), the breach of contract itself, which is officially established into a formal notice. When the judge is seized, the creditor has a legal option between dissolution or enforced performance offered by article 1184 paragraph 2, which leads to the question of judicial characteristic - involving an important argument - of the dissolution.Finally, judicial dissolution causes apparent consequences : retrospective effect on contract but, overall, there are specific effects : termination of contract involving return of goods, values and performances between parties coming from the judicial decision.If dissolution's concept had been studied before into its fundamentals, its story or its diverse forms, it allows to explore the reverse side of this theory into as a new critical reading which recalls the original function of this legal action : to permit creditor to defend in case of breach of contract
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Pontes, Marcos Cesar. "Polarization effects on infrared target contrast." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1998. http://handle.dtic.mil/100.2/ADA353099.
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Thesis (M.S. in Systems Engineering) Naval Postgraduate School, September 1998.Thesis advisor(s): Alfred W. Cooper, David D. Cleary. "September 1998." Includes bibliographical references (p. 173-174). Also available online.
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Gaffaney, Tyler. "An Analysis of the Contract Year Phenomenon in the NBA: Do Players Perform Better or Worse." Scholarship @ Claremont, 2013. http://scholarship.claremont.edu/cmc_theses/768.
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The present study uses a novel measure of over performance (percent deviation from career average) to analyze the contract year phenomenon in the NBA. Historically, the literature has pointed toward over performance across almost all statistical measures of performance. However, previous research has assumed that all players are universally affected by the presence of a contract year in the same manner. The present study finds significant results that contradict previous research by dividing the sample of players into subgroups by age, career PER and position. Furthermore, the results of this paper’s statistical analysis illustrate the first examples of systematic underperformance in a contract year. More specifically, this study finds that for certain subsets of players, shooting percentage, usage percentage and field goal attempts decrease in the presence of a contract year.
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Drew, Derek Stephen. "The effect of contract type and size on competitiveness in construction contract bidding." Thesis, University of Salford, 1994. http://usir.salford.ac.uk/14717/.
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Flanagan and Norman (1982b) examined the bidding performances of three contractors. In developing this study, the aim of this research is to demonstrate through statistical modelling that, in terms of competitiveness, competing contractors are influenced, to varying degrees, by contract type and size and that a competitiveness relationship exists between contractor size and contract size. Bidding behaviour between construction firms is regarded as the outcome of strategic management decisions undertaken in an economic setting. Contractors are seen to compete for construction work in a competitive environment made up of a series of market sectors, each containing an amalgam of contract types and sizes, while clients are viewed as initiators of the whole contracting process. Contractors are shown to respond to client demands by deciding on a strategic domain within which to operate, which contracts to bid for and, if opting to bid, the appropriate bid level. Two approaches to modelling competitiveness are offered. The first approach examines the relationship between competitiveness and variability in bidding and a four-way classification system of bidder behaviour is developed. The main goal of this work, however, is contained in the second approach, which uses multiple regression to construct a competitiveness model - a prediction equation relating bidder competitiveness (the dependent variable) to the independent variables of bidder (analysed individually and also grouped according to size), contract type and contract size. The regression model shows that differences in competitiveness are greater for different contract sizes than different contract types. The most competitive contractors appear to be those with a preferred contract size range. The results are inconclusive in providing evidence that large bidders are more competitive on larger contracts and vice versa.
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Garrido, Huidobro Mattias. "Unfair Contract Terms in European Contract Law : Legal consequences for and beyond Swedish Contract Law." Thesis, Uppsala universitet, Juridiska institutionen, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-229817.
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Recent case law from the ECJ on one of the most important EU contract law legislation has left questions open about the compatibility of Swedish contract law with the Unfair Contracts Term Directive. The case law on Article 6 (1) in the directive seem to have changed the view on how to deal with the legal consequence of an unfair term in consumer contracts; namely that unfair terms cannot be adjusted but need to be declared invalid. This essay examines how the effects from the ECJ case law provide new light upon Swedish contract law. The effect creates a clash of ideas and rationalities between Union law and Swedish contract law. Unfair terms cannot be adjusted as the relevant Swedish legislation provides. An unfair term needs to be invalid, and if necessary, such an unfair term can in certain circumstances be complemented with default rules from national contract law. This does not only seem to change the interpretation and application of the Swedish law, but it also form an underlying tension between the instrumental market-functional Union law and the more justice oriented Swedish private law. Furthermore, as we move towards a new European civil code, perhaps these tensions and clashes may say something about where the discipline of European Private Law is headed.
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Barten, Peter G. J. "Contrast sensitivity of the human eye and its effects on image quality." Bellingham, Wash. (1000 20th St. Bellingham WA 98225-6705 USA) : SPIE, 1999. http://dx.doi.org/10.1117/3.353254.
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Thesis (doctoral)--Technische Universiteit Eindhoven, 1999."SPIE digital library." Originally published: Knegsel : HV Press, 1999. Includes bibliographical references and index. Also available in print version.
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Morrison, Jeffrey Glenn. "The effects of hue and contrast on binary classification." Thesis, Georgia Institute of Technology, 1987. http://hdl.handle.net/1853/28758.
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Wu, Ray-chin. "Simultaneous contrast effects in luminous and non-luminous colour." Thesis, Heriot-Watt University, 2005. http://hdl.handle.net/10399/115.
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