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Traits provide an informative approach to examine species-environment interactions. Often, species-by-species approaches are inefficient to generate generalizable ecological relationships and do not predict species responses to environmental changes based on specific traits species possess. Multiple lines of inquiry and multi-scale approaches are best for assessing environment-trait responses. This thesis examines important questions not specifically addressed before in traits-based research. Chapter one explores biological and ecological trait associations incorporating ontogenetic diet shifts for New River fishes. Niche shift analysis as a chapter one sub-objective quantitatively support where species-specific diet shifts likely occur. Strong biological-ecological trait associations, some intuitive and others not so intuitive, were found that relate biological structure to ecological function. Improved understanding of trait associations, including what factors influence others, supports inference of ecology of fishes. Chapters two and three examine spatial and intraspecific trait variability. Chapter two specifically examines large-scale life history trait variability along latitudinal gradients for twelve widely distributed fish species, including directionality of trait variation, and hypothesizing how optimal traits change with large-scale environmental factors. Strong positive and negative patterns found include average total length of newly hatched larvae, average total length at maturation, average spawning temperature, average egg diameter, and maximum length. These five traits are correlated with other adaptive attributes (i.e. growth rate, reproductive output, and longevity/population turnover rate). In contrast to latitudinal scale, Chapter three examines trait variability of white sucker (Catostomus commersonii) and fantail darter (Etheostoma flabellare) as a function of small-watershed scale spatial factors and anthropogenic disturbance. Toms Creek and Chestnut Creek white sucker and fantail darter displayed positive response to disturbance, contrary to past studies. Lower resource competition, and / or competitive exclusion of fishes with similar niche requirements are possible mechanisms. All three objectives support understanding of trait association and variability as a useful foundation in ecological applications and for formulating plans for conservation and management of species. / Master of Science

Le projet de thèse est divisé en deux parties. D’une part, la génération directionnelle et singulière de plasmons de surface (SPPs) par des ouvertures nanométriques a été réalisé et optimisé par le biais de microscopie de fuites radiatives (LRM). Nous démontrons expéri- mentalement qu’une structure plasmonique composée de nano-ouvertures en forme de T et Λ permet de contrôler le couplage unidirectionnel et radialdes SPPs grâce au spin de la lumière incidente. Pour confirmer nos résultats expérimentaux, nous développons un modèle analytique qui décrit les coupleurs plasmoniques constitués de nano-ouvertures par représentation multidipolaire, permettant ainsi une explication théorique de la directionalité et de la formation de vortex plasmonique. L’optimisation des paramètres géométriques tels que l’angle au sommet des ouvertures en forme de Λ montre la possibilité de maximiser la directivité et le taux d’extinction à la fois pour le couplage directionnel et la génération des vortex dans le champ lointain. Parailleurs, notre méthode basée sur la détection LRM, permet une analyse quantitative et est avérée être une technique de caractérisation sophistiquée pour cartographier le champ plasmonique. Il fournit également plusieurs nouvelles possibilités pour la focalisation de SPP contrôlée en polarisation.D’autre part,le couplage spin-orbite de la lumière dans un guide et son effet réciproque sont réalisées et confirmées expérimentalement et théoriquement. Les coupleurs et découpleurs réseaux sur le guide d’ondes sont d’abord développés et étudiés. La sortie parfaite de la lumière confinée par le découpleur nous offre la possibilité de détecter les ondes guidées. La fluorescence des nanocristaux déposés sur la surface de l’échantillon montre une autre possibilité de visualiser directement la propagation de la lumière dans le guide d’onde. Le couplage directionnel contrôlé par spin est réalisé par des antennes en forme de Λ et est confirmé par des images en champ sombre avec des découpleurs et des images de fluorescence. En outre, l’effet réciproque est observé avec une imperfection de polarisation de sortie qui est expliqué théoriquement par le fait que les ordres de diffraction par les antennes en forme de Λ influent sur les états de polarisation finaux. Ainsi, l’effet réciproque est parfaitement réalisé par la sélection d’une région spécifique de diffraction dans le plan de Fourier. La caractérisation quantitative des interactions spin-orbite nous permet d’envisager le développement de nouveaux coupleurs directionnels dans le domaine de la nanophotonique tels que le traitement quantique de l’information. / In this project, two contributions are reported. Firstly, the directional and singular generation of Surface Plasmon Polaritons (SPPs) in the nanoapertures is investigated using the Leakage Radiation Microscopy (LRM). We demonstrate experimentally spin-driven directional coupling as well as singularity (inward) and vortex (outward radial coupling) of SPPs by nanostructures built with T-shaped and Λ-shaped apertures.To support our experimental findings, we develop an analytical model based on a multidipolar representation of Λ- andT-shaped aperture plasmonic couplers, allowing a theoretical explanation of both directionality and singular SPP formation. The optimal apex angle of Λ-shaped apertures shows the possibility to maximize the directiviy and extinction ratio for both directional coupling and singular SPP generation in the far field. Besides, our method based on LRM detection, allows quantitative analysis and is proven to be a sophisticated characterization technique for mapping the SPP vortex field.It also provides several new possibilities for polarization-controlled SPP sub-wavelength focusing.Secondly, the spin-orbit coupling of light into a photonic waveguide and its reciprocal effect are realized and confirmed both experimentally and theoretically. Coupler and decoupler gratings on the waveguide are firstly developed and investigated. The radiation of the confined light from the decoupler provides us a possibility to detect the guided waves. The fluorescence of nanocrystals deposited on the sample surface shows another possibility to directly visualize the light propagation in the waveguide. The spin-driven directional coupling is achieved by Λ-shaped antennas and is certified by the dark field images with decouplers and the fluorescence images. Furthermore, the reverse effect is observed with an imperfection of output polarization which is explained that the diffraction orders by the Λ-shaped apertures influence the final polarization states based on an analytical model. Thus, the reciprocal effect is realized by selecting the specific diffraction region on the Fourier plane. We believe that the quantitative characterization of spin-orbit interactions will pave the way for developing new directional couplers in the field of nanophotonics such as quantum information processing and so forth.

Due to the fact that many of the secondary school pupils who experience difficulty in choosing a career, also appear to have problems with their time perspective, an investigation into the possible link between these concepts was undertaken. A literature study was done where the major dimensions of time perspective were identified continuity/directionality and locus of control; optimism/pessimism; structure. Analyses were done on the principal factors influencing time perspective and career choice. A reliable measuring instrument was developed in order to measure the secondary school pupil's time perspective. The results of the empirical investigation indicated that time perspective does play a significant role in the career choice of secondary school pupils. Gender and intellectual potential do not appear to have a significant bearing on time perspective. The educational implications of the findings are discussed, and guidelines regarding methods of improving a child's time perspective are given to both teachers and parents. / Psychology of Education / M. Ed. (with specialisation in Guidance and Counselling (Psychology of Education))

This thesis investigates if Environmental, Social and Governance (ESG) investments can be considered as an independent asset class. As ESG and responsible investing has increased substantially in recent years, responsible investments have entered the portfolios with other asset classes too. Therefore, there is a need in studying ESG investment properties with other financial asset classes. By collecting daily price data from October 2007 to December 2018, we research the directionalities between ESG, ethical, conventional, commodities and currency. Initially, we employed a MODWT, multiscale investment horizon wavelet analysis transformation of the data. The decomposed wavelet data is then applied in pairwise linear and non-linear Granger causality estimations to study the directionality relationships dependent on investment horizon. Additionally, econometric filtering processes have been employed to study the effects of volatility on directionality relationships. The results mainly suggest significant directionality relationships between ESG and the other asset classes. On the medium-term investment horizon, almost all estimations indicate strict bidirectionality. Thus, on the medium-term, ESG can be said to be integrated with the other asset classes. For the long-term horizon, most relationships are still predominantly bidirectional between ESG and all other asset classes. The biggest differences are found on the short-term horizon, with no directionality found between ESG and commodities that cannot be explained by volatility. Furthermore, most directionality relationships also disappear when controlling for the volatility transmission between ESG and currency on the short-term horizon. Thus, our findings suggest significantly more integration between ESG and ethical and conventional as bidirectionality overwhelmingly prevails regardless of investment horizon. As previous research has found similarities between ethical and conventional as well as ESG having similar characteristics to commodities as conventional and ethical, we suggest that ESG should be considered as being integrated and having strong similarities with other equities. Thus, it should be treated as being part of the conventional equity asset class. Deviations from bidirectionality could be caused by ESG variable specific heterogeneity. However, despite our rejection of ESG as an independent asset class, it still carries significant potential as it excludes firms with climate-harming practices, thereby helping in combating climate-related as well as social and governance issues the world is facing.

In Chapters 1 and 2, we introduce the definition of interpolating refinable function vectors in dimension one and high dimensions, characterize such interpolating refinable function vectors in terms of their masks, and derive their sum rule structure explicitly. We study biorthogonal refinable function vectors from interpolating refinable function vectors. We also study the symmetry property of an interpolating refinable function vector and characterize a symmetric interpolating refinable function vector in any dimension with respect to certain symmetry group in terms of its mask. Examples of interpolating refinable function vectors with some desirable properties, such as orthogonality, symmetry, compact support, and so on, are constructed according to our characterization results. In Chapters 3 and 4, we turn to the study of general matrix extension problems with symmetry for the construction of orthogonal and biorthogonal multiwavelets. We give characterization theorems and develop step-by-step algorithms for matrix extension with symmetry. To illustrate our results, we apply our algorithms to several examples of interpolating refinable function vectors with orthogonality or biorthogonality obtained in Chapter 1. In Chapter 5, we discuss some possible future research topics on the subjects of matrix extension with symmetry in high dimensions and frequency-based non-stationary tight wavelet frames with directionality. We demonstrate that one can construct a frequency-based tight wavelet frame with symmetry and show that directional analysis can be easily achieved under the framework of tight wavelet frames. Potential applications and research directions of such tight wavelet frames with directionality are discussed. / Applied Mathematics

The vibration of and wave propagation in periodic cellular structures are analyzed. Cellular structures exhibit a number of desirable multifunctional properties, which make them attractive in a variety of engineering applications. These include ultra-light structures, thermal and acoustic insulators, and impact amelioration systems, among others. Cellular structures with deterministic architecture can be considered as example of periodic structures. Periodic structures feature unique wave propagation characteristics, whereby elastic waves propagate only in specific frequency bands, known as "pass band", while they are attenuated in all other frequency bands, known as "stop bands". Such dynamic properties are here exploited to provide cellular structures with the capability of behaving as directional, pass-band mechanical filters, thus complementing their well documented multifunctional characteristics. This work presents a methodology for the analysis of the dynamic behavior of periodic cellular structures, which allows the evaluation of location and spectral width of propagation and attenuation regions. The filtering characteristics are tested and demonstrated for structures of various geometry and topology, including cylindrical grid-like structures, Kagom and eacute; and tetrhedral truss core lattices. Experimental investigations is done on a 2-D lattice manufactured out of aluminum. The complete wave field of the specimen at various frequencies is measured using a Scanning Laser Doppler Vibrometer (SLDV). Experimental results show good agreement with the methodology and computational tools developed in this work. The results demonstrate how wave propagation characteristics are defined by cell geometry and configuration. Numerical and experimental results show the potential of periodic cellular structures as mechanical filters and/or isolators of vibrations.

Despite the plethora of SLA research conducted on the acquisition of the definite marker in noun phrase configurations in L2 Arabic and English (e.g., Sarko, 2007; Master, 1997; Collier, 1987; Anderson, 1984; Kharma, 1981), there is as yet no definitive description of how noun phrases are acquired and why errors persist after advanced stages in L2 learning. Results, as shown by Butler (2002), are inconclusive, and the primary causes of difficulties in the acquisition of the definite marker in noun phrase configurations remain unclear. Recently, the internal syntax-semantics interface (Cuza & Frank, 2011; Montrul, 2010; Tsimpli & Sorace, 2006; Sorace, 2003, 2004) and the specificity-definiteness distinction (Ionin, 2003; Ionin et al., 2004; Ionin et al., 2008) have been considered as appropriate frameworks for exploring the acquisition of noun phrases and other structural features. The structure of noun phrase configurations in Arabic and English offers a complex interface between form and meaning for L2 learners with multiple cases of matches and mismatches between specificity and definiteness. In this three-article dissertation project, two of which were conducted in a bidirectional methodological framework with L1 Arabic-L2 English and L1 English-L2 Arabic learners, I explored the acquisition of three cases of noun phrase configurations. In the first study, I investigated the acquisition of plural noun phrase configurations that carry generic and specific readings at the initial state of L2 learning. Using three data collection instruments: written translation; error detection and correction; and forced choice elicitation, I tested the predictions made by the Interface Hypothesis (IH) and the Full Transfer (FT) Hypothesis. Results showed that L2 learners in both directions tend to transfer noun phrase configurations from L1 into L2, a result that I took to support the FT hypothesis. In addition, it took L1 English-L2 Arabic learners two years of instruction to recover from this L1 effect. The second study aimed at confirming the result of the first study, but in the acquisition of the definite marker in generic singular noun phrase configurations in the L1 English-L2 Arabic direction. The behavior of generic singular noun phrases in L2 Arabic offers a good testing ground since it has numerous similarities and differences with English. Two conditions were established: a matching condition and a mismatching condition. Both conditions were tested in the L1 English-L2 Arabic direction. Results showed a similar pattern to the one recorded in the first study. Typological proximity and distance were found to be important determiners of language acquisition of the in/definiteness configurations of singular noun phrases. In the third study, I shifted to the exploration of a more complex type of noun phrases; namely the definite Iḍāfah construction in Modern Standard Arabic (MSA) and its equivalent noun phrase configurations in English in the two directions. I started with a common difference between MSA and English. Whereas in MSA there is a canonical configuration in terms of head-complement ordering and head-complement definiteness, English is tolerant of more than one permissible configuration. I operationalized the acquisition of these noun phrases in terms of head-complement ordering and head-complement definiteness. Results showed a clear effect of L1 transfer in both directions; knowledge of L1 noun phrase configurations acts as the initial step in L2 learning. I concluded that both communities of L2 learners face problems that vary according to the L1 noun phrase configuration at hand. However, in the L1 English-L2 Arabic direction, learners reached a satisfactory level of performance in the Iḍāfah construction after two years of instruction. I approached this finding as a result of intensive Focus-on-Form Episodes (Loewn, 2005) that the Iḍāfah construction receives in MSA instruction. At the conclusion of this research project I highlighted some implications for the second language acquisition and teaching of noun phrases. The overall results were couched in a broader perspective that characterizes the initial state of L2 learning of noun phrases in + article and – article languages, the effects of typological proximity and distance, and the effects of Instructed SLA. For the pedagogical implications, I called for the integration of the semantics of the definite marker while presenting noun phrases in textbooks. I also recommended the use of explicit instruction and structured-input activities (VanPatten, 2004; Marsden & Chen, 2011) as effective pedagogical tools that foster form-meaning mapping in the acquisition of L2 Arabic and English noun phrases.

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Due to the fact that many of the secondary school pupils who experience difficulty in choosing a career, also appear to have problems with their time perspective, an investigation into the possible link between these concepts was undertaken. A literature study was done where the major dimensions of time perspective were identified continuity/directionality and locus of control; optimism/pessimism; structure. Analyses were done on the principal factors influencing time perspective and career choice. A reliable measuring instrument was developed in order to measure the secondary school pupil's time perspective. The results of the empirical investigation indicated that time perspective does play a significant role in the career choice of secondary school pupils. Gender and intellectual potential do not appear to have a significant bearing on time perspective. The educational implications of the findings are discussed, and guidelines regarding methods of improving a child's time perspective are given to both teachers and parents. / Psychology of Education / M. Ed. (with specialisation in Guidance and Counselling (Psychology of Education))