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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Proceso sobre la ordenación de la Iglesia valentina : entre los arzobispos de Toledo, Rodrigo Jiménez de Rada, y de Tarragona, Pedro de Albalat : 1238-1246 /

Castell Maiques, Vicente, January 1996 (has links)
Tesis doctoral--Alicante--Universidad, 1990. / Bibliogr. p. 59-76 (vol. 1). Index.
102

Automatické propojování lexikografických zdrojů a korpusových dat. / Automatic linking of lexicographic sources and corpus data

Bejček, Eduard January 2015 (has links)
Along with the increasing development of language resources - i.e., new lexicons, lexical databases, corpora, treebanks - the need for their efficient interlinking is growing. With such a linking, one can easily benefit from all their properties and information. Considering the convergence of resources, universal lexicographic formats are frequently discussed. In the present thesis, we investigate and analyse methods of interlinking language resources automatically. We introduce a system for interlinking lexicons (such as VALLEX, PDT-Vallex, FrameNet or SemLex) that offer information on syntactic properties of their entries. The system is automated and can be used repeatedly with newer versions of lexicons under development. We also design a method for identification of multiword expressions in a parsed text based on syntactic information from the SemLex lexicon. An output that verifies feasibility of the used methods is, among others, the mapping between the VALLEX and the PDT-Vallex lexicons, resulting in tens of thousands of annotated treebank sentences from the PDT and the PCEDT treebanks added into VALLEX. Powered by TCPDF (www.tcpdf.org)
103

Síntese e Caracterização do Composto Heterobimetálico trans-[(SO3)(cyclam)Co-NCS-Ru(NH3)4(NCS)](BF4) / Synthesis and characterization of heterobimetallic compound trans-[(SO3) (cyclam) Co-NCS-Ru (NH3) 4 (NCS)] (BF4)

Silva, Maria Aparecida Santiago da January 2009 (has links)
SILVA, Maria Aparecida Santiago da. Síntese e Caracterização do Composto Heterobimetálico trans-[(SO3)(cyclam)Co-NCS-Ru(NH3)4(NCS)](BF4). 2009. 101 f. Dissertação (Mestrado em química)- Universidade Federal do Ceará, Fortaleza-CE, 2009. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-06-02T19:19:53Z No. of bitstreams: 1 2009_dis_massilva.pdf: 2887733 bytes, checksum: 595bebd5e087742ed6f88b835417ecf7 (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-07-20T19:55:07Z (GMT) No. of bitstreams: 1 2009_dis_massilva.pdf: 2887733 bytes, checksum: 595bebd5e087742ed6f88b835417ecf7 (MD5) / Made available in DSpace on 2016-07-20T19:55:07Z (GMT). No. of bitstreams: 1 2009_dis_massilva.pdf: 2887733 bytes, checksum: 595bebd5e087742ed6f88b835417ecf7 (MD5) Previous issue date: 2009 / Trans-[Co(cyclam)(SO3)(NCS)]·4H2O, trans-[Ru(NH3)4(NCS)(SO4)], and trans-[(SO3)(cyclam)Co−NCS−Ru(NH3)4(NCS)](BF4) complexes, where cyclam = 1,4,8,11-tetraazacyclotetradecane, were synthesized and characterized by X-ray difraction, vibrational and electronic (ultraviolet, visible and near infrared) spectroscopies, and electrochemical techniques. The electronic communication between Co and Ru metal centers of the binuclear complex was evaluated by electrochemistry and electronic spectrocopy in the near infrared region. Crystals suitable for X-ray studies were only isolated for the trans-[Co(cyclam)(SO3)(NCS)]·4H2O complex. The obtained results indicate a monoclic structure with cyclam ligand at the equatorial plane and SO32− and NCS− moieties occupying the axial positions being coordinated through, respectively, sulfur and nitrogen atoms. This result is reinforced by the observation, in the vibrational spectrum, of bands typically assigned to the cyclam ligand in a trans configuration. The cyclic voltammograms obtained for this compound indicate as Electrochemical-Chemical-Electrochemical mechanism. In fact, the spectroelectrochemical experiments obtained at -0.80 V vs Ag/AgCl show that this compound, upon reduction, suffers a substitution reaction in which the SO32− and NCS− moieties are replaced by solvent molecules (L) thus forming [Co(cyclam)(L)2]2+ type complexes. The observation in the vibrational spectrum of the trans-[Ru(NH3)4(NCS)(SO4)] complex of the 2132, 887 e 478 cm-1 bands assigned, respectively, to the νCN, νCS e δ(NCS) vibrational modes of the NCS− ligand indicates that this moiety is coordinated through the nitrogen atom. Electrochemical and spectroscopic studies of this compound in aqueous medium indicate that the reduction of the metal center induces the replacement of SO42− ligand by a water molecule. The synthesis of the binuclear compound, therefore, was made under reductive conditions aiming to produce the aquo-complex and, then, replace the water molecule by a coordination site of the trans-[Co(cyclam)(SO3)(NCS)]·4H2O complex. The results obtained for the isolated material hints that the binuclear complex is formed with the NCS− fragment as the bridge ligand. The acquired cyclic voltammogram presents two redox process with the half-wave formal potentials (E1/2) observed at −0.27 and 0.13 V vs Ag|AgCl and being assigned to the Co and Ru metal centers, respectively. In comparison to the monomers, the positive potential shift reflects the stabilization of the reduced state of the ruthenium metal atom (RuII) and the destabilization of the cobalt metal center (CoIII). This result is assigned to the coordination to an oxidated metal center, CoIII, whose effective nuclear charge increased the electronic delocalization increasing the withdrawing character of the NCS− bridge ligand. The comproportionation constant, Kc = 5.78 x 106, was calculated from the difference between the E1/2 values. The Kc value indicates a strong electronic communication between the metal atoms and classifies this binuclear complex as a mixed valence system of class II. / Os compostos trans-[Co(cyclam)(SO3)(NCS)]·4H2O, trans-[Ru(NH3)4(NCS)(SO4)] e trans-[(SO3)(cyclam)Co−NCS−Ru(NH3)4(NCS)](BF4), onde cyclam = 1,4,8,11-tetraazaciclotetradecano, foram sintetizados e caracterizados por difrações de raios-X, espectroscopias vibracional na região do infravermelho e eletrônica nas regiões do ultravioleta e visível (UV-Vis) e por técnicas eletroquímicas. O grau de comunicação eletrônica entre os átomos de Co e Ru do complexo binuclear foi avaliado por eletroquímica e espectroscopia eletrônica na região do infravermelho próximo. Apenas para o complexo trans-[Co(cyclam)(SO3)(NCS)]·4H2O foi possível a obtenção de cristais que permitiram a determinação estrutural. Os dados obtidos indicam estrutura monoclínica com o ligante cyclam no plano equatorial e os ligantes SO32− e NCS− ocupando posições trans e coordenados ao átomo de Co através, respectivamente, dos átomos de S e N. Este resultado é reforçado através da observação, no espectro vibracional, de bandas tipicamente atribuídas ao ligante cyclam quando este se encontra em uma geometria trans. Os resultados de voltametria cíclica deste composto indicam um mecanismo eletroquímico-químico-eletroquímico. De fato, os experimentos de espectroeletroquímica (potencial controlado em -0,80 V vs Ag/AgCl) indicam que este composto experimenta, após redução, reação de substituição das moléculas SO32− e NCS− por moléculas do solvente (L), formando compostos do tipo [Co(cyclam)(L)2]2+. A observação, no espectro vibracional do complexo trans-[Ru(NH3)4(NCS)(SO4)], das bandas em 2132, 887 e 478 cm-1, atribuídas aos modos de νCN, νCS e δ(NCS), respectivamente, do ligante NCS−, indica a coordenação deste grupo através do átomo de nitrogênio. Estudos eletroquímicos e de espectroscopia eletrônica deste composto em meio aquoso indicam que a redução do centro metálico induz a reação de substituição do ligante SO42− por uma molécula de H2O. A reação para formação do composto binuclear, portanto, foi realizada em condições redutoras a fim de induzir a formação do aquo-complexo de rutênio e, em seguida, a reação de substituição da molécula de H2O por um sítio de coordenação do monômero trans- [Co(cyclam)(SO3)(NCS)]·4H2O. Os resultados obtidos para o material isolado indicam que há a formação do complexo binuclear com o ligante NCS− ocupando a posição ponte. A curva voltamétrica obtida para este composto apresenta dois pares de ondas redox com potenciais formais de meia-onda (E1/2) em −0,27 e 0,13 V vs Ag|AgCl atribuídos, respectivamente, aos centros metálicos de Co e Ru. Comparativamente aos monômeros, há a observação de um deslocamento positivo de potencial o que reflete a estabilização do estado reduzido para o átomo de rutênio, RuII, e desestabilização do estado oxidado para o átomo de cobalto, CoIII. Este resultado é atribuído a coordenação a um centro oxidado, CoIII, cuja carga nuclear efetiva aumenta a deslocalização de densidade eletrônica aumentando o caráter retirador do ligante ponte NCS−. O valor da constante de comproporcionamento, Kc = 5,78 x 106, calculada a partir da diferença entre os valores de E1/2, indica um forte grau de comunicação entre os centros metálicos e classifica este complexo como um sistema de valência mista de classe II.
104

Regulating Working Memory In Emotionally-Laden Contexts

January 2015 (has links)
abstract: Individual differences in working memory capacity partly arise from variability in attention control, a process influenced by negative emotional content. Thus, individual differences in working memory capacity should be predictive of differences in the ability to regulate attention in emotional contexts. To address this hypothesis, a complex-span working memory task (symmetry span) was modified so that negative arousing images or neutral images subtended the background during the encoding phase. Across three experiments, negative arousing images impaired working memory encoding relative to neutral images, resulting in impoverished symmetry span scores. Additionally, in Experiment 3, both negative and arousing images captured attention and led to increased hit rates in a subsequent recognition task. Contrary to the primary hypothesis, individual differences in working memory capacity derived from three complex span tasks failed to moderate the effect of negative arousing images on working memory encoding across two large scale studies. Implications for theories of working memory and attention control in emotional contexts will be discussed. / Dissertation/Thesis / Masters Thesis Psychology 2015
105

How emotional videos influence motor timing and retrospective duration judgments.

Zhang, Anran January 2018 (has links)
An emotionally involved event may subsequently appear shorter than an event of relative indifference for people. How are time-related behaviors influenced while people are emotionally affected? The purpose of this study was to test if ongoing estimates and retrospective reports of duration are similarly affected by emotional states. To test, 30 s emotional video clips were rated for Valence and Arousal by six participants. The videos were then used in a timing experiment where a new set of participants (twenty-five persons) carried out a repetitive motor timing paradigm while watching the videos and subsequently reported the perceived duration of the clip. In each of ten trials, participants first synchronized to a 700 ms isochronous interval with their index finger, and then continued unsupported as five different video clips were played in sequence, with each clip lasting 30s. At the end of each trial, participants reported their retrospective duration judgment of every video clip, and rated every video chip for Valence and Arousal. Emotion ratings suggested that the videos affected the subjects’ emotional states. Repetitive motor timing was not reliably affected by emotional states. Instead, retrospective reports of durations were affected by emotional states such that the durations estimated under high arousal conditions were significantly longer than those under low arousal conditions. The difference in results between repetitive motor timing and retrospective reports may be accounted for by the interval of 700 ms being too short to be cognitive-related.
106

Molecular beam epitaxial growth and characterization of GaAs and GaAsBi based semiconductor devices

Mahtab, Mahsa 22 December 2020 (has links)
GaAs(1-x)Bi(x) (x = 0 to 17%) optical properties were investigated by spectroscopic ellipsometry (in energy ranges of 0.37–9.0 eV). Optical features in the dielectric function, known as the critical points, were distinguished and modeled using standard analytic line shapes. The energy dependence of the critical points energies was thoroughly investigated as a function of Bi content and thin film strain. Critical points analysis in the Brillion zone showed that the top of the valence band is most strongly dependent on Bi content compared to other parts of the band structure. In addition, an interesting new critical point was observed that is attributed to alternative allowed optical transitions made possible by changes to the top of the valence band caused by resonant interactions with Bi orbitals. Several of the critical points were extrapolated to 100% Bi and showed reasonable agreement with the calculated band structure of GaBi. GaAs(1-x)Bi(x) (x= 03, 0.7 and 1.1%) based p+/n and n+/p heterostructure photovoltaic performance was characterized through IV and CV measurement. By introduction of Bi into GaAs, a non-zero EQE below the GaAs band edge energy was observed while the highest efficiency was obtained by ~ 0.7% Bi incorporation. EQE spectrum was modeled to find the minority carrier diffusion lengths of ~ Ln = 1600 and Lp = 140 nm for p-doped and n-doped GaAs92Bi08 in the doping profile of 10^15 - 10^16 cm^-3. Analysis of the CV measurement confirmed the background n-doping effect of Bi atom and the essential role of the cap layer to reduce multi-level recombination mechanisms at the cell edge to improve ideality factor. Low temperature grown GaAs was optimized to be used as photoconductive antenna in THz time-domain spectroscopy setup. The As content was investigated to optimize photo-carrier generation using 1550 nm laser excitation while maintaining high mobility and resistivity required for optical switching. A barrier layer of AlAs was added below the LT-GaAs to limit carrier diffusion into the GaAs substrate. Moreover, LT-GaAs layer thickness and post-growth annealing condition was optimized. The optimized structure (2-µm LT-GaAs on 60-nm AlAs, under As2:Ga BEP of ~7, annealed at 550°C for 1 minute) outperformed a commercial InGaAs antenna by a factor of 15 with 4.5 THz bandwidth and 75 dB signal-to-noise ratio at 1550 nm wavelength. / Graduate
107

Effect of Positive and Negative Emotion on Naming Accuracy in Adults with Aphasia

Nielsen, Courtney Paige 12 June 2020 (has links)
This is a preliminary study investigating the effects of emotion on a confrontational naming task in people with aphasia (PWA). Previous research investigating the effects of emotion on various language tasks in PWA has produced mixed findings with some suggesting a facilitative effect and others an inhibitory effect. Participants included 9 adults with aphasia as the result of a stroke, resulting in the presence of word-finding deficits (i.e., anomia). Participants named images in positive, negative, and neutral conditions. Responses were scored as either correct or incorrect; incorrect responses were coded further to illustrate individual error patterns. The majority of participants demonstrated a decrease in naming accuracy in the negative condition compared to the preceding and subsequent neutral conditions. The results of this study suggest that negative emotional arousal may cause PWA to devote attentional resources to emotional regulation and away from the linguistic task, thus interfering with language performance. Further research is needed to support these preliminary findings.
108

Effects of Positive and Negative Emotional Valence on Response TimeDuring a Confrontational Naming Task: Findings from People with Aphasia and Young Adults

Loveridge, Corinne Jones 17 June 2020 (has links)
The purpose of the current study was to determine the effect of emotional arousal and valence on linguistic processing of adults with aphasia and neurotypical young adults. Nine people with aphasia (at least 6 months left hemisphere stroke and presenting with word retrieval deficits) and 20 young adults (reporting no evidence of neurological injury) participated. All participants completed a confrontational naming task during three conditions that were manipulated according to emotional arousal and valence: positive (high arousal, positive valence), negative (high arousal, negative valence), and neutral (low arousal, neutral valence). Average response time was measured for pictures named accurately within each condition. In general, participants with aphasia named pictures more slowly than young adult participants. Neither participant group had significant differences in response time across conditions. Individual participants varied in how emotional valence affected their response times. Further research is needed to identify what factors lead to differing responses to the high-arousal conditions.
109

Valence-specific Enhancements in Visual Processing Regions Support Negative Memories:

Kark, Sarah Marie January 2019 (has links)
Thesis advisor: Elizabeth A. Kensinger / Research in four parts examines the effects of valence on the neural processes that support emotional memory formation and retrieval. Results show a consistent valence-specific enhancement of visuocortical engagement along the ventral visual stream and occipital cortex that supports negative memories to a greater extent than positive memories. Part I investigated the effects of valence on the interactions between trial-level physiological responses to emotional stimuli (i.e., heart rate deceleration) during encoding and subsequent memory vividness. Results showed that negative memory vividness, but not positive or neutral memory vividness, is tied to arousal-related enhancements of amygdala coupling with early visual cortex during encoding. These results suggest that co-occurring parasympathetic arousal responses and amygdala connectivity with early visual cortex during encoding influence subsequent memory vividness for negative stimuli, perhaps reflecting enhanced memory-relevant perceptual enhancements during encoding of negative stimuli. Part II examined links between individual differences in post-encoding increases is amygdala functional connectivity at rest and the degree and direction of emotional memory biases at retrieval. Results demonstrated that post-encoding increases in amygdala resting state functional connectivity with visuocortical and frontal regions predicted the degree of negative memory bias (i.e., better memory for unpleasant compared to pleasant stimuli) and positive memory bias, respectively. Further, the effect of amygdala-visuocortical post-encoding coupling on behavioral negative memory bias was completely mediated by greater retrieval-related activity for negative stimuli in visuocortical areas. These findings suggest that those individuals with a negative memory bias tend to engage visual processing regions across multiple phases of memory more than individuals with a positive memory bias. While Parts I-II examined encoding-related memory processes, Part III examined the effects of valence on true and false subjective memory vividness at the time of retrieval. The findings showed valence-specific enhancements in regions of the ventral visual stream (e.g., inferior temporal gyrus and parahippocampal cortex) support negative memory vividness to a greater extent than positive memory vividness. However, activation of the parahippocampal cortex also drove a false sense of negative memory vividness. Together, these findings suggest spatial overlap in regions that support negative true and false memory vividness. Lastly, Part IV utilized inhibitory repetitive transcranial magnetic stimulation (rTMS) to test if a portion of occipito-temporal cortex that showed consistent valence-specific effects of negative memory in Parts I-III was necessary for negative memory retrieval. Although some participants showed the hypothesized effect, there was no group-level evidence of a neuromodulatory effect of occipito-temporal cortex rTMS on negative memory retrieval. Together, the results of the current dissertation work highlight the importance of valence-based models of emotional memory and consistently implicated enhanced visuosensory engagement across multiple phases of memory. By identifying valence-specific effects of trial-level physiological arousal during encoding, post-encoding amygdala coupling during early consolidation, and similarities and differences between true and false negative memories, the present set of work has important implications for how negative and positive memories are created and remembered differently. / Thesis (PhD) — Boston College, 2019. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Psychology.
110

How different pay-for-performance remuneration plans affect executive performance

Bouwmeester, Michael Paul 10 June 2012 (has links)
Orientation: The design of remuneration plans and pay-for-performance is recognised as a long-standing management practice. Almost all remuneration plans include incentive and bonus schemes in order to motivate the desired performance of individuals by rewarding them based on performance.Research purpose: The primary aim of the study was to assess how different pay-for-performance remuneration plans affect performance.Motivation for the study: Research and literature indicates that pay-forperformance can indeed influence employee performance; however there are instances where there are negative effects associated with pay-forperformance. Pay-for-performance is in instances considered controversial owing to the large remuneration packages that executives in particular receive.Research design, approach and method: The research methodology that was utilised was a quantitative study, by undertaking a structured cross sectional survey of executives and managers. The survey was distributed to 201 potential respondents and the results of 118 respondents were utilised in the data analysis. Four different types of pay-for-performance plans were assessed, namely Merit Pay, Bonus Pay, Full Shares, and Share Appreciation Rights. Expectancy Theory was utilised as a basis in an attempt to explain the motivation of executives and managers with respect to the influence that different types of pay-for-performance plans have on performance.Main findings/results: All of the pay-for-performance plans were found to have a positive effect on the motivation of employees; however it was found that the most significant factor relating to motivation of employees was expectancy as opposed to the preference of the type of reward (valence). The rewards preferences, as determined by this study, in order of preference were Merit Pay, Full Shares, Bonus Pay, and Share Appreciation Rights.Practical/Managerial implications: This study confirms that it is more important to understand individuals and what motivates them than the actual rewards offered. Different rewards have different motivational effects, however the reward itself is not the dominant determinant with regards to motivational as a whole.Contribution/value-add: This study further clarifies the influence that different pay-for-performance remuneration plans have on the future performance of executives and managers. / Dissertation (MBA)--University of Pretoria, 2011. / Gordon Institute of Business Science (GIBS) / unrestricted

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