Habitat loss and fragmentation drives the current extinction crisis. The processes through which it affects biodiversity, however, are complex and poorly understood. This is especially true for spatially complex regions that comprise a mosaic of land-use types, which often range from protected areas to dense human settlements. In such human-modified landscapes, it is important to determine the extent and impact of changing land-use patterns on biodiversity if we are to meet conservation targets or regain ecosystem services. My analyses of coastal forests in KwaZulu-Natal suggest that extensive loss of forests (82%) incurred an extinction debt, modelled to match the 11 bird species now listed as threatened locally. Forest fragments are now also smaller, fewer, further apart and more encroached by human land uses than in the past. Yet, species interactions with the gradient of habitat conditions that now surround forest fragments may have forestalled the realisation of predicted extinctions. I found that natural matrix habitats adjacent forest fragments (e.g. grasslands and woodlands) may facilitate dispersal, enable species spillover from forest fragments, and buffer forest interiors from changes in abiotic conditions associated with high contrast matrix habitats (e.g. agricultural plantations). However, when natural matrix habitats were transformed, these processes were disrupted, which suggest that the effect of landscape change on coastal forest diversity may stretch beyond forest loss per se and the deterministic extinctions predicted by conventional species-area relationships. Next, I determined that the response of different bird species to habitat fragmentation parameters (i.e. area, connectivity and matrix habitats), depended on life-history traits such as body size, feeding guild and habitat specialization. Extinction risk was, however, not a function of species traits or the fragmentation parameter species responded to. This means that a conservation approach that only focuses on restoring a single fragmentation parameter (e.g. area) may not be successful in halting predicted extinctions, simply because multiple factors may determine extinction risk in coastal forests. The interpretation of biodiversity patterns in fragmented landscapes may, however, also be influenced by spatial scale. I therefore used a fractal-based sampling design to test how sampling at fine, intermediate and coarse scales influences (1) beta diversity of and (2) inferences from the modelled contribution of niche- versus dispersal-based assembly processes in structuring tree and bird assemblages. I showed that inferences from beta diversity are scale dependent. As a result, studies with similar sampling effort and temporal sampling protocol, but with different sampling grains are likely to report dissimilar ecological patterns, which may ultimately lead to inappropriate conservation strategies. This thesis provides information of how land-use changes impact on biodiversity patterns and derived processes in a human-modified landscape. It also highlights some conservation opportunities in the coastal forest landscape mosaic, where conservation and restoration actions should focus on both forest fragments and on the surrounding matrices. The conservation of natural matrices may buffer forest communities from impacts associated with high contrast habitat edges, enhance natural plant regeneration through species spillover, provide important linkages between forest fragments, boost regional diversity and allow coastal forests to track environmental change under changing climatic conditions. / Thesis (PhD)--University of Pretoria, 2014. / tm2015 / Zoology and Entomology / PhD / Unrestricted

Mass spectrometry with electrospray ionization is an excellent method for structural analysis of coordination compounds with outstanding sensitivity and selectivity. However, it fails to detect some low-polar rhenium complexes. This master thesis describes derivatization method of non-ionizable rhenium complexes with 1,2-dihydroxybenzene and 2,3- dihydroxytoluenene. Fragmentation mechanisms and structure of prepared complexes was studied using high resolution mass spectrometry and collision-induced dissociation (CID). Furthermore, density functional theory (DFT) computational method was used for prediction of bond cleavage based on bond lengthening.

Parallel double-station video observations paired with spectroscopic video observations are a good way to study millimetre-sized meteoroids. Almost two decades of video observations of meteors at the Ondřejov observatory give us broad database to study large quantities of meteoroids and their properties. In this work we combined spectral video observations and results of the modelling of the fragmentation of meteoroids. Along with complex infor- mation about meteoroid's trajectories and orbits, this can give us better understanding about origin, internal structure etc. of these millimetre-sized interplanetary bodies. Meteoroids that contained small grains tend to release the sodium early. Since there is a smaller amount of sodium for Na depleted meteoroids, the sodium was released earlier than it was released for meteoroids with same grain sizes and without the sodium depletion. Overall, meteoroids with sodium depletion showed different composition: they were composed of stronger material without very small grains and they did not showed very bright wakes. Two iron meteoroids on Halley type orbits were observed. They are probably remnants of complicated early years of our solar system. The dis- tribution of grain sizes of Jupiter-family members was in a good agreements with results from the COSIMA...

Cancer is the second leading cause of death worldwide and affects millions of people every year. Furthermore, the available treatments often lead to severe side effects, thus improving radiation treatment is meaningful. Photoactivation therapy seeks to build in heavy atoms into the DNA of cancer cells, as markers, then activating them to cause secondary radiation that damages the DNA of the targeted cells only. This has been suggested but is not well understood. Hence this study seeks to investigate how a reduced model system of iodine-marked DNA is fragmented due to ionization. Computer simulations with eleven separate starting configurations of the molecule 5-iodocytidine were analyzed, for ionization levels from an average 0.03 up to 0.33 electrons removed per atom (e/N), during 200 femtoseconds (fs). A Python program was written in order to estimate bond sensitivities and identify fragments. While 5-iodocytidine resembles an iodized DNA-base it is still a rather simple model system, far from a double stranded DNA chain, and the simulations were limited to non-targeted ionization and an isolated environment. Results of this thesis include that the sugar ”backbone” of 5-iodocytidine seems to be most sensitive to ionization, fragmenting in several pieces after 150-200 fs at ionization levels of 0.30-0.33 e/N, while the rest of the molecule mostly remained intact. These results appear promising since back bone fragmentation is crucial for disrupting cancer cell growth. / Cancer är den näst största dödsorsaken i världen och påverkar miljontals människor varje år. Dessutom leder tillgängliga behandlingar ofta till allvarliga bieffekter, därför är det meningsfullt att förbättra strålbehandling. Fotoaktiveringsterapi går ut på att bygga in tunga atomer i cancercellernas DNA, som markörer, och därefter aktivera dem för att orsaka sekundär strålning vilket endast skadar de fokuserade cellerna. Detta har studerats men processerna är inte fullt klarlagda, därför ämnar denna studie att undersöka hur ett förenklat modelsystem av jod-märkt DNA fragmenteras till följd av jonisering. Datorsimuleringar för elva olika begynnelsevillkor av molekylen 5-iodocytidine analyserades, för joniseringsnivåer från ett genomsnitt 0.03 upp till 0.33 borttagna elektroner per atom (e/N), under 200 femtosekunder (fs). Ett Pythonprogram skrevs i syfte att uppskatta bindningarnas känslighet och identifiera fragment. Även om 5-iodocytidine liknar en jodiserad DNA-bas så är det fortfarande ett tämligen enkelt modelsystem, långt ifrån två sammanbunda DNA-strängar. Simuleringarna var dessutom avgränsade till icke-fokuserande jonisering och en isolerad omgivning. Resultat från den här avhandlingen innefattar att socker-”ryggraden” av 5-iodocytidine verkar vara mest känslig för jonisering, och fragmenteras i flera bitar efter 150-200 fs vid joniseringnivåer 0.30-0.33 e/N, medan resten av molekylen oftast förblir intakt. Dessa resultat ser lovande ut eftersom fragmentering av ryggraden är särskilt viktig för att hämma tillväxten av cancerceller.

El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / This study aims to propose a new alternative to optimize drilling and blasting processes from the mathematical and geological viewpoint using simulation software. The main objective is to design a systematic model of steps that can generate a simulation through JkSimBlast. This simulation must represent the best alternative for the design of drilling mesh and explosive selection to be implemented in the field. To achieve this goal, a seven-step process diagram was proposed, including geology, design aspects (burden and spacing across the areas of influence algorithm), analysis of physical parameters such as detonation rate, drill-mesh design, explosives selection and fragmentation analysis, simulation tests that could represent the field designs, and selection of the most optimal simulation. For the collection of parameters in the field, we have used MicroTrap Software and WipFrag, which have allowed the design of a mesh according to the needs of the rocky massif. The most optimal simulation was implemented at Caravelí Mining Company-Estrella Unit and had a positive impact on the optimization of drilling and blasting, as the costs of these processes were reduced by 14.6%. Specifically, the costs of explosives were reduced by 2.6% and the costs of drilling steels by 10.4%. The performance of the loading machine advance/shot increased by 13.2% and 15.6%, respectively. Copyright 2019.

South Africa is the third most biologically diverse country in the world and has developed advanced biodiversity legislation and policies to protect its natural environment. Biodiversity is the natural wealth of all living things on earth, from which a multitude of ecosystem services that sustain life emanate. The dramatic shift towards urban living however, places tremendous pressure on these biological resources. Local government has received international recognition as the level of government that is key to securing long-term global sustainability. The cities of Cape Town and Durban in South Africa have each developed their own biodiversity and open space conservation systems to conserve and protect the remaining biodiversity and open spaces within their respective municipal boundaries. The aim of this research was to explore the local biodiversity and open space conservation strategies in these two cities, with a view to understanding: (1) the informants, and emerging form, of urban conservation strategies in these two cities in light of their variable biophysical templates and histories; and (2) the physical landscape pattern in each city, and from this information, infer likely ecological outcomes, for these two cities. The study made use of both qualitative and quantitative research methods. The results reveal that while both cities are facing similar issues in terms of biodiversity loss and natural habitats becoming increasingly fragmented, the way in which these issues manifest in these different cities is unique. The City of Cape Town is highly developed and fragmented but has more land secured under its conservation plan compared to the City of Durban. Durban however, has a large rural land component which remains under the governance of traditional leaders. The study reveals that there are many factors that play a role in the development and success of conservation plans, including: the local context, biophysical templates, city histories, social informants of how these plans emerge and evolve, contemporary governance structures as well as local pressures. Biodiversity conservation in South African cities still faces many challenges which need to be overcome in the near future. These solutions will need to be city specific.

Practices of land use in Utah show need for community action aimed at more adequate utilization of land and water resources. Use of land for crop production in Utah is limited by topography, soil type, elevation, climate, and moisture. Because of limitations imposed, only a small portion of the land area may be used for cultivated farming. As a rule, large land holdings in Utah are not regularly tilled but are used as range for raising livestock.

My thesis project is attempting to investigate the notion of estrangement as a qualitative effect and discover various strategies and technics of estrangement in the field of architecture.These investigations will aim to design a cultural center as an institute for discovering more about the displaced situation of mankind in the twenty-first century, producing a defamiliarized aesthetic that is both alien and strangely contextual to our new cultural identity which embraces the concepts of disorientation and otherness. This center will be designed as a public exhibition and community building, integrating a high variety of programs and functions for attracting people of all ages and backgrounds, addressing the instability and fragility of our environment.Architecture is always incomplete and reliant on multiple layers of interaction and engagement, I aim to produce spaces that are challenging, lacking clear boundaries or hierarchies which demand new forms of interaction between architecture and subject, and offer a new understanding of space and material.

京都大学 / 新制・課程博士 / 博士(医学) / 甲第24475号 / 医博第4917号 / 新制||医||1062(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 生田 宏一, 教授 竹内 理, 教授 上野 英樹 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

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