Understanding dispersal and gene flow in human-modified landscapes is crucial for effective conservation. Seed dispersal governs colonization, recruitment, and distribution of plant species, whereas both pollen and seed dispersal determine gene flow among populations. This PhD thesis tests the effect of rotational shepherding on seed dispersal and gene flow in fragmented calcareous grasslands. Calcareous grasslands (Gentiano-Koelerietum pyramidatae vegetation) in Central Europe are semi-natural communities traditionally used for rotational grazing that experienced a decline of plant species during the 20th century due to abandonment of shepherding. This PhD profits from a management project started in 1989 in Bavaria, Germany to reconnect previously abandoned calcareous grasslands in three non-overlapping shepherding systems. Two vegetation surveys in 1989 and 2009 revealed colonizations in previously abandoned grasslands reconnected by shepherding. First, I propose a comprehensive approach to identify determinants of community-level patch colonization rates based on 48 habitat specialist plants by testing competing models of pre-dispersal and dispersal effects and accounting for post-dispersal effects. Mean source patch species occupancy in 1989, and structural elements in focal patches related to establishment explained community-level patch colonization rates. Secondly, by adapting the community analysis to all 31 individual species of the same community with sufficient data, I corroborate the role of shepherding to support dispersal for a range of species, even if they lack seed morphological traits related to zoochory. Thirdly, for the habitat specialist Dianthus carthusianorum, I genotyped 1,613 individuals from 64 populations at eleven microsatellites to test the effect of dispersal by sheep on spatial genetic structure at the landscape scale. Genetic distances between grazed patches of the same herding system were related to distance along herding routes, whereas ungrazed patches showed isolation by geographic distance. Lastly, within individual grassland patches, shepherding significantly decreases the degree of relatedness among neighboring individuals (kinship structure) and increases genetic diversity. My thesis contributes towards understanding the effects of zoochory on spatial dynamics in plant populations across scales.

The central purpose of this study is the integration of modem philosophical thinking with different chaos theory principles and definitions to form relational perspectives. Relations are used in different contexts to base the causes of deterministic chaos (chaost) in the laws of nature which constitutes order. The chaost-attractor is used as subjective conception to investigate the possibilities of hidden order in a seemingly chaotic state of the objective reality. Relevant definitions of the chaos theory were analysed methodically and transcendentally with the aid of concepts of order and relations. Attention is given to the broad associations and analogies from philosophy and other disciplines which relate to the connectivity of objects to form systems. Subjective model development was done which is used to consequentially analyse some statements from published research which applied principles of chaost. It is argued that: the intrinsic properties of objects determine the causality of forces which bind objects to compose systems; a web of interactive bonds functions subjective to laws of nature which determine whether a system is in a state of order, chaost or real chaos; a dynamical transfer of many intrinsic and asymmetric properties via internal bonds constitutes non-linear connectivity which causes a sensitivity for initial conditions. It is found that the chaost of the chaos theory is not the same as real, objective chaos. The random-like evolution of a dynamic system is determined by the occurrence of irregularities and uncertainties in its internal order. A web of interactive bonds distribute small changes self-similar and scale-relevant. The difficulty in describing and explaining the complex behaviour of composed entities is simplified by the proposed web-chaost model. / Thesis (M.A. (Philosophy))--North-West University, Potchefstroom Campus, 2006.

Understanding dispersal and gene flow in human-modified landscapes is crucial for effective conservation. Seed dispersal governs colonization, recruitment, and distribution of plant species, whereas both pollen and seed dispersal determine gene flow among populations. This PhD thesis tests the effect of rotational shepherding on seed dispersal and gene flow in fragmented calcareous grasslands. Calcareous grasslands (Gentiano-Koelerietum pyramidatae vegetation) in Central Europe are semi-natural communities traditionally used for rotational grazing that experienced a decline of plant species during the 20th century due to abandonment of shepherding. This PhD profits from a management project started in 1989 in Bavaria, Germany to reconnect previously abandoned calcareous grasslands in three non-overlapping shepherding systems. Two vegetation surveys in 1989 and 2009 revealed colonizations in previously abandoned grasslands reconnected by shepherding. First, I propose a comprehensive approach to identify determinants of community-level patch colonization rates based on 48 habitat specialist plants by testing competing models of pre-dispersal and dispersal effects and accounting for post-dispersal effects. Mean source patch species occupancy in 1989, and structural elements in focal patches related to establishment explained community-level patch colonization rates. Secondly, by adapting the community analysis to all 31 individual species of the same community with sufficient data, I corroborate the role of shepherding to support dispersal for a range of species, even if they lack seed morphological traits related to zoochory. Thirdly, for the habitat specialist Dianthus carthusianorum, I genotyped 1,613 individuals from 64 populations at eleven microsatellites to test the effect of dispersal by sheep on spatial genetic structure at the landscape scale. Genetic distances between grazed patches of the same herding system were related to distance along herding routes, whereas ungrazed patches showed isolation by geographic distance. Lastly, within individual grassland patches, shepherding significantly decreases the degree of relatedness among neighboring individuals (kinship structure) and increases genetic diversity. My thesis contributes towards understanding the effects of zoochory on spatial dynamics in plant populations across scales.

In the context of continuous innovations in information and communication technology (ICT) and its impact on higher education, this descriptive study explores the state of instructional technology (IT) integration by university lecturers in pre-service secondary school teacher education programs in Zimbabwe. Specifically, the study examines how the lecturers conceptualize IT integration, how they integrate IT into their instruction, the support given by their institutions, and the constraints they face. The qualitative methodology used is basic or generic in nature (Merriam, 1998). Twenty-one lecturers in the colleges of education at 3 universities participated. The 3 data collection methods used are questionnaires, interviews and analysis of documents. Analysis of data was inductive and Miles and Huberman’s (1994) interactive data analysis model was employed. Findings show that the conceptualization of IT and its integration by the majority of the lecturers was largely as hardware in nature, with focus put on viewing technological tools as audiovisual aids. Lecturers with qualifications in educational technology (ET) viewed IT and its integration from what Schiffman (1995) calls a narrow systems view. Most of the lecturers used technological tools for illustrating key points in their lecture delivery and lecturers who used computers used these for lecture preparation. Lecturers’ computer proficiency and competencies were at the basic level in Internet usage, with little confidence shown in basic productivity software skills and in IT integration tasks and processes. The lecturers’ integration of IT was at the Entry and Adoption stages (Dwyer, Ringstaff and Sandholtz, 1991). Institutional support was characterized by poor availability and access to appropriate technological tools by both lecturers and students, and in the context of a hyper-inflationary operating environment, constraints ranged from lack of institutional funding, to the absence of an IT integration policy framework, and lack of appropriate initial and continuous staff development. This study is part of the genesis of instructional technology research in the Zimbabwean context. It is hoped that insights gleaned will influence policy, practice and future research. From a global perspective, this study will add to the limited knowledge and literature on instructional technology integration in “developing” and/or low-income countries like Zimbabwe.

Diplominiame darbe nagrinėjamas specialusis atraminių elementų erdvės atvejis, kai atraminis elementas yra II – os eilės viršvektorius ( p = 2 ). Pirmieji du darbo paragrafai yra referatyvinio pobūdžio. Pirmajame paragrafe gautos diferencijuojamos daugdaros struktūrinės lygtys, pateikiamos kai kurių diferencialinių geometrinių objektų ( skaliarinės funkcijos, tenzorinio lauko, viršvektorinio lauko ir afiniosios sieties objekto ) diferencialinės lygtis. Antrajame paragrafe afiniųjų ir tenzorinių siečių pagalba apibrėžta tenzoriaus invariantinio diferencijavimo operacija ir surastos tenzoriaus kovariantinės išvestinės. Surastos sąlygos kada tenzoriaus kovariantinės išvestinės, apibrėžto afiniosios sieties pagalba sutampa su šio tenzoriaus kovariantinėmis išvestinėmis, apibrėžtomis tenzorinės sieties pagalba. Trečiajame paragrafe apibrėžiama antros eilės atraminių viršvektorių erdvė, surastos šios erdvės struktūrinės lygtys ir ištirta liečiamosios ir koliečiamosios erdvių struktūra. Ketvirtajame paragrafe nagrinėjamos koliečiamosios erdvės normalizacijos. Tiesinės sieties pagalba kolie���iamojoje erdvėje išskiriami du invariantiniai poerdviai. Iš tiesinės sieties komponenčių ir jų pirmojo tęsinio sukonstruotos šios erdvės nepilna afinioji ir nepilna tenzorinė sietys, surasti šių siečių tarpusavio ryšiai, surastos pakankamos sąlygos, kad nepilnoji afinioji sietis sutaptų su nepilnosios tenzorinės sieties indukuota afiniąja sietimi. Čia tai pat surastos erdvės su nepilnąja... [toliau žr. visą tekstą] / In work it is examined special case of spaces support elements, when support elements are the super – vectors of the second order ( p = 2 ). The space of the second order support super – vectors is certain, the structural equations of this space are found and the structure tangential and cotangential spaces is researched. Further it is examined to space tangential spaces normalization. By means of linear connectivity in tangential space are detach two invariant subspaces. By means of components of linear connectivity and their first continuation are designed incomplete affine and incomplete tensors connectivity of this space, also connection between them is found. Further by means of linear connectivity natural normalization of space is examined, it is proved that the object of linear connectivity and its first continuation induces incomplete super – vector connectivity of this space. The structural equations of space with incomplete super – vector and complete super – vector connectivity are found. As operation of invariant differentiation of a super - vector field is certain, analogues of Richi and Bianca identities are received.

An almost unbroken fringing reef runs along the east coast of Africa, the lagoon inside the reef is the foundation of almost all artisanal fisheries. It is a low-tech fishery conducted by many people. Some areas can have up to 19 fishermen per square kilometer. High fishing pressures, coupled with declining fish stocks has led to changes in mean size and reproductive age of many exploited species. There is a vital and urgent need for scientifically based management systems, including the utilization of genetic information to guide management practices. This thesis aims to investigate the presence of genetic structures in the western Indian Ocean. In order to do that we first investigated the historical patterns of connectivity throughout the region (paper I). In papers II and III we focused on local scale connectivity in Kenya and Tanzania and finally in paper IV we investigate the large-scale contemporary gene flow throughout the Western Indian Ocean. In paper III we also investigate the temporal genetic variation at one site and compare it to the small-scale genetic variation along a stretch of the Kenyan coastline. Some overall conclusions that can be drawn from my body of work are: there are genetic structures present in the western Indian Ocean even though the apparent lack of physical barriers. Major oceanic currents aid evolutionary dispersal patterns. A single geographic site need not be genetically homogenous or temporally stable. Island sites are genetically more homogenous than mainland sites. In conclusion, there are clear and distinct genetic structures present especially in Siganus sutor, the most targeted fish for the artisanal fishery in East Africa. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.</p>

Business organizations rely on exploitation and efficiency to provide short-term results and on exploration and innovation for their future viability. The ability to simultaneously exploit and explore has been termed organizational ambidexterity. Front-line managers who are able to encourage both exploitation and exploration from their employees should therefore be quite successful, but this is not an easy task. Managerial interventions seek to align the employees’ interests with the manager’s interests and therefore can be perceived as more controlling than enabling, thereby negatively impacting ambidexterity. This case study uses agency theory as a theoretical lens to understand managerial interventions that could focus attention on individual employees’ actions that are both exploitative and explorative in an enabling fashion to allow for success. The study advances managerial practice, addresses gaps in the literature on ambidexterity, and advocates development of a new management theory by recommending that managers focus their interactions into three sets of tasks, 1) those that connect the employee to the organization, 2) those that connect the manager to the employee, and 3) those that enable the employee to go forward and own their decisions, within these connections. We argue, this combination of interventions work together to encourage an environment of both exploitation and exploration, or contextual ambidexterity, with the opportunity to be successful in both the short-term and into the future.

<p>Diffusion tensor imaging (DTI) has emerged as a unique method to characterize brain tissue microstructure non-invasively. DTI typically provides the ability to study white matter structure with a standard voxel resolution of 8&mu;L over imaging field-of-views of the extent of the human brain. As such, it has long been recognized as a promising tool not only in clinical research for the diagnostic and monitoring of white matter diseases, but also for investigating the fundamental biological principles underlying the organization of long and short-range cortical networks. However, the complexity of brain structure within an MRI voxel makes it difficult to dissociate the tissue origins of the measured anisotropy. The tensor characterization is a composite result of proton pools in different tissue and cell structures with diverse diffusion properties. As such, partial volume effects introduce a strong bias which can lead to spurious measurements, especially in regions with a complex tissue structure such as interdigitating crossing fibers or in convoluted cortical folds near the grey/white matter interface.</p><p>This dissertation focuses on the design and development of acquisition and image reconstruction strategies to improve the spatial resolution of diffusion imaging. After a brief review of the theory of diffusion MRI and of the basic principles of streamline tractography in the human brain, the main challenges to increasing the spatial resolution are discussed. A comprehensive characterization of artifacts due to motion and field inhomogeneities is provided and novel corrective methods are proposed to enable the acquisition of diffusion weighted data with 2D mulitslice imaging techniques with full brain coverage, increased SNR and high spatial resolutions of 1.25&times;1.25&times;1.25 mm<super>3</super> within an acceptable scan time. The method is extended to a multishot k_{_z}-encoded 3D multislab spiral DTI and evaluated in normal human volunteers.</p><p>To demonstrate the increased SNR and enhanced resolution capability of the proposed methods and more generally to assess the value of high-spatial resolution in diffusion imaging, a study of cortical depth-dependence of fractional anisotropy was performed at an unprecedented <italic>in-vivo</italic> inplane resolution of 0.390&times;0.390&mu;m<super>2</super> and an investigation of the trade-offs between spatial resolution and cortical specificity was conducted within the connectome framework.</p> / Dissertation

During normal development, face processing involves a gradual shift from a featurally oriented style to a mature configural style by adolescence. This shift may coincide with increased right hemispheric dominance for faces supporting configural processing. Previous studies suggest that individuals diagnosed with ASD continue to process faces using individual parts and features into adulthood. This continued bias may be due to deficits in configural processing abilities. The current study investigated measures of functional connectivity during featural and configural processing of faces in broad autism phenotype sibling (ASD-sibs) children compared to age, sex, and handedness matched normal developing (ND) controls and in children diagnosed with an Autism Spectrum Disorder compared to ASD-matched ND controls. Results indicate that children with ASD and ASD-sibs were capable of performing configural processing tasks at similar performance levels to those of ND children. Additionally, patterns of functional network connectivity for configural processing in ASD-sibs were similar to those observed in ND controls. Few network-wide hemispheric differences emerged between groups. While behavioral performance and overall network-wide patterns of connectivity suggest a face processing network that is capable of supporting configural processing in ASD and ASD-sibs, abnormalities were observed in specific regions. The amygdala and fusiform face area showed fewer interactions with the rest of the face processing network in ASD children compared to ND during configural, but not featural processing. Additionally, hemispheric comparisons show greater differences between ASD and ND controls in the right fusiform face area. The ability of these regions to communicate with other regions in the face network could be important for social motivation and attention during configural processing. Interestingly, network connectivity in ASD children during passive viewing of faces, objects, and textures without featural or configural manipulations showed a more functionally integrated, and less segregated network with a lower “wiring cost” during non-face conditions compared to ND children. ASD-sibs may demonstrate a similar milder pattern.

Network resiliency pertains to the vulnerability of telecommunication networks in the case of failures and malicious attacks. With the increasing capacity catering of network for the booming multi-services in Next Generation Networks (NGNs), reducing recovery time and improving capacity efficiency while providing high quality and resiliency of services has become increasingly important for the future network development. Providing network resiliency means to rapidly and accurately reroute the traffic via diversely routed spare capacity in the network when a failure takes down links or nodes in the working path. Planning and optimization for NGNs require an efficient algorithm for spare capacity allocation (SCA) that assures restorability with a minimum of total capacity. This dissertation aims to understand and advance the state of knowledge on spare capacity allocation in network resiliency for telecommunication core networks. Optimal network resiliency design for restorability requires considering: network topology, working and protection paths routing and spare capacity allocation. Restorable networks should be highly efficient in terms of total capacity required for restorability and be able to support any target level of restorability. The SCA strategy is to decide how much spare capacity should be reserved on links and to pre-plan protection paths to protect traffic from a set of failures. This optimal capacity allocation problem for survivable routing is known as NP-complete. To expose the problem structure, we propose a model of the SCA problem using a matrix-based framework, named Distributed Resilience Matrix (DRM) to identify the dependencies between the working and protection capacities associated with each pair of links and also to capture the local capacity usage information in a distributed control environment. In addition, we introduce a novel ant-based heuristic algorithm, called Friend-or-Foe Resilient (FoF-R) ant-based routing algorithm to find the optimal protection cycle (i.e., two node-disjoint paths between a source-destination node pair) and explore the sharing ability among protection paths using a capacity headroom-dependent attraction and repulsion function. Simulation results based on the OMNeT++ and AMPL/CPLEX tools show that the FoF-R scheme with the DRM structure is a promising approach to solving the SCA problem for survivable routing and it gives a good trade off between solution optimality and computation speed. Furthermore, for the SCA studies of survivable networks, it is also important to be able to differentiate between network topologies by means of a robust numerical measure that indicates the level of immunity of these topologies to failures of their nodes and links. Ideally, such a measure should be sensitive to the existence of nodes or links, which are more important than others, for example, if their failure causes the network’s disintegration. Another contribution in this dissertation is to introduce an algebraic connectivity metric, adopted from the spectral graph theory, namely the 2nd smallest eigenvalue of the Laplacian matrix of the network topology, instead of the average nodal degree, to characterize network robustness in studies of the SCA problem. Extensive simulation studies confirm that this metric is a more informative parameter than the average nodal degree for characterizing network topologies in network resiliency studies.