This investigation has determined the presence of biological nitrogen fixation in two reservoirs in the southwestern United States: Lake Arlington and Lake Ray Hubbard. Subsequent tests have gathered baseline data on the effects of various biological, chemical, and physical parameters on in situ nitrogen fixation in these reservoirs. Of specific importance is the relationship between nitrogen fixation arid occasional blooms of blue-green algae which produce such problems as testes and odors in these water-supply impoundments.

Master of Science / Food Science - Animal Sciences & Industry / Fadi Aramouni / Blue-green pigments have the ability to form in crushed and whole garlic cloves following a rapid series of enzymatic and non-enzymatic reactions. Economic losses associated with a reduction in organoleptic quality of garlic (Allium sativum L.) containing blue-green pigments can be incurred. Preventing blue-green pigment formation can mitigate potential financial and brand equity damages. To prevent pigment formation, inactivation of the enzyme which yields pigment substrates is essential. Two methods to inactivate the enzyme associated with pigment formation were explored: blanch treatment of whole garlic cloves (100°C, 5 min); and soaking of whole, non-blanched garlic cloves in low pH (<3.0) acetic or citric acid pickling solutions for seven days. The blanching treatment was effective in inactivating the enzyme as the pigment substrate decreased by approximately 99% as compared with pigment substrate concentrations in non-blanched garlic cloves. Soaking whole garlic cloves in low pH (<3.0) pickling solutions did not result in enzyme inactivation as pigments formed in cloves soaked in the acetic acid pickling solutions; however pigments did not form in cloves soaked in the citric acid pickling solution. This may be due to the different effect mono- and poly-carboxylic acids have on the permeability of garlic cell membranes. Blanching garlic cloves can be implemented as a processing step to prevent pigment formation. Soaking garlic in a low pH pickling solution comprised of a poly-carboxylic acid does not inactivate the enzyme associated with pigment formation but pigment formation can be prevented. Other methods presented in the literature to prevent pigment formation include controlling growth, harvest and storage conditions, as well as treating garlic clove homogenates with chemical additives.

Hypoxia or dissolved oxygen concentrations < 2 mg/L is a problem in estuaries worldwide. In Lake Pontchartrain, a 250 km2 de-faunated zone exists as a result of salinity stratification and episodic hypoxia. Mature common rangia clams (Rangia cuneata) are not found within this zone. Blue crabs (Callinectes sapidus) are important estuarine predators and may move in and out of the hypoxic zone to feed on hypoxia-stressed rangia clams. To test the effects of hypoxia on predation, rangia clams were exposed experimentally to severe hypoxic conditions (< 0.75 mg/l) for 72-hours and then presented to blue crabs. One hypoxic and one normoxic clam were added to each aquarium containing a blue crab for each trial, and crab feeding choices were observed and recorded. I found prey choice varied among crabs, but in general, the experimental data demonstrates that crabs chose to feed on hypoxia-stressed clams over clams kept under normoxic conditions.

As estrelas azuis tardias (blue straggler stars ou estrelas BS) são estrelas de sequência principal que apresentam um aparente atraso evolutivo em relação às suas vizinhanças. Elas foram identificadas inicialmente na sequência principal de aglomerados globulares acima do ponto de turnoff no diagrama HR. Desde então, têm sido encontradas em todos os ambientes estelares: aglomerados abertos e globulares, galáxias anãs próximas e entre as estrelas de campo na Galáxia. O principal objetivo deste trabalho é construir uma grande amostra de estrelas BS no campo galáctico. Para tanto, métodos de separação desses objetos de estrelas BHB foram comparados com critérios de seleção que envolvem parâmetros atmosféricos estimados pelo SEGUE Stellar Parameter Pipeline (SSPP). Tal procedimento permitiu incluir também estrelas com magnitudes g maiores que 18, antes excluídas pelos métodos tradicionais para objetos com razão sinal-ruído menores que 9. Os métodos apresentados neste trabalho permitiram a seleção de uma amostra de 8001 candidatas a estrelas BS que foram analisadas cinematicamente, através de suas velocidades radiais. Verificou-se que aproximadamente um quinto dessa amostra (cerca de 1500 objetos) possui características que a associa à corrente de Sagitário, sugerindo uma origem extragaláctica para tais objetos. / Blue straggler stars (BSSs) are main sequence stars that exhibit an apparent evolutionary delay over the region where they are found in the HR diagram. They were initially identified in the main sequence of globular clusters above the turnoff point. Since then, they have been found in many different stellar environments: globular and open clusters, near dwarf galaxies, and also in the field of the Galaxy. The main goal of this work is to build a large sample of BSSs in the galactic field region. In order to accomplish this task, classical methods of separation of BSS from BHB stars were compared with proposed restrictions based on their atmospheric parameters, which are estimated by the SEGUE Stellar Parameter Pipeline (SSPP). The latter procedure allowed to include stars with magnitudes g greater than 18, not handled by traditional methods when signal-noise ratio is smaller than 9. The selection methods gathered a sample of 8001 BS stars. These stars were kinematically analyzed through their radial velocities. The results suggest that many of them (about 1500) can have extragalactic origin, associated with Sagittarius stream.

青綠山水在中國繪畫史上歷史悠久，可追溯到魏晉時期（220-420），甚至更早，可謂中國山水畫科之始。然而，在經歷隋唐（581-907）的成熟和兩宋（960-1279）的高峰後，隨著水墨繪畫的興起，文人趣味的改變，加上材料技術的失傳，青綠山水在元代開始衰落。儘管這樣，還是有人致力於青綠創作，理想世界成為作品中時常表達的憧憬。 / 本文包含四個部分：「緒論」闡述青綠山水的定義，並回顧傳統青綠山水的沿革。第一章梳理傳統青綠山水對理想世界的描繪，把它分成「隱逸」、「桃源」和「仙境」三類，從技法和主題來分析作品背後的意涵。第二章先以近代畫壇大師為例，指出他們對青綠山水創作的重視既在於表達理想世界，更在於對傳統技法的保存和延續。而現當代的青綠創作雖形式繁雜，但至少有五種面貌。第三章則闡述個人如何參考傳統技法和風格為創作元素，展現對傳統和當下的思考。文章期能對青綠山水這一古老畫科與理想世界的關係作一探討，並為當代青綠山水的創作再添註釋。 / Regarded as the origin of the genre of landscape painting, blue-and-green landscape painting has a long history in China, dating from the Wei and Jin periods (220-420) and even earlier. It was developed in the Sui and Tang dynasties (581-907) and was at its glorious status in the Song dynasty (960-1279). However, a change in the taste of the literati class and the loss of the related techniques and materials gave rise to monochrome ink painting, and as a result, the blue-and-green tradition declined in the Yuan dynasty (1271-1368). Despite the prevailing trend of Chinese landscape painting, there are still people who devote themselves to the blue-and-green style and use it to depict an ideal world. / This thesis consists of four sections. In the Introduction, I formulate a definition for blue-and-green landscape painting and trace its development in the narratives of Chinese art. Chapter One straightens out the depictions of an ideal world in the blue-and-green tradition, dividing them into ‘recluse’, ‘peach blossom spring’ and ‘immortal land’, and deciphers the meaning of the works regarding their techniques and subjects. Chapter Two studies the masters of the modern and contemporary art world and their landscape views. The value of blue-and-green landscape painting is still highly regarded not only because it is used to depict an ideal world, but also seen as a means to preserve and continue the traditional painting techniques. The contemporary blue-and-green landscape paintings come in a variety of styles and yet there are at least five categories from my observation. The final chapter is my reflection on the Chinese tradition and on the presence as I express these by making reference to the traditional techniques and styles. In studying the close relationship between the primitive genre of blue-and-green landscape painting and an ideal world, this thesis intends to offer a new perspective in painting blue-and-green landscape in a modern context. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / 蔡德怡. / Parallel title from English abstract. / Thesis (M.Phil.) Chinese University of Hong Kong, 2015. / Includes bibliographical references (leaves 84-90). / Abstracts in English and Chinese. / Cai Deyi.

Programme evaluation research examined the criminological and socio-legal issues of a Claimant Fraud Investigation Program (CFIP) operating inside the workers' compensation system. Qualitative and quantitative methods were used to evaluate the programmes' choice of deterrence as an instrumental mechanism for achieving compliance. Key aspects of the programme were analysed from both criminological and socio-legal standpoints. Justice and liberty tensions were examined in reference to the programmes' deterrence mechanisms and the perceptions of fourteen participants' were thematically analysed. The study develops an analytically useful concept of light blue-collar crime that could be applied to other organisations and scenarios. The study concluded the programme is not effective and has more of a symbolic than instrumental value. It conducts itself ethically, however, there are problems with its' choice of deterrence and the study indicates there is a low probability for a deterrent effect. Recommendations are made for other actors and institutions to play non-deterrence based roles intended to achieve compliance.

There is ample evidence that climate change is impacting on phenology and it has been suggested that this may generate trophic mismatches. A key system for investigating phenology and trophic mismatch occurs in spring in temperate deciduous woodlands, where folivorous caterpillars and their predators, insectivorous passerines, are reliant upon ephemeral resources for reproductive success and survival. However, studies are primarily conducted within single-site, oak- (Quercus sp) dominated woodland and focus on a single caterpillar species, winter moth (Operophtera brumata), despite these passerines being habitat generalists with large geographic ranges. It remains to be seen whether insights gained from these studies can be generalised on the landscape scale across different habitats. In this thesis, I explore the extent to which geographic and habitat variation operates in this system and attempt to expand the system beyond a linear single-species food chain into a more biologically realistic multi-species food web. I also identify the most important environmental factors predicting the phenology of the passerines to allow better predictions of how their phenology could alter under future climate change scenarios. To address these questions, I established a novel 220km transect of Scotland incorporating 40 field sites that vary in elevation and the type of deciduous woodland habitat, monitoring six blue tit (Cyanistes caeruleus) nestboxes, tree and invertebrate phenology and abundance, at each site throughout the springs of 2014-16. Firstly, I assess how blue tit occupancy and productivity are affected by the variation in fine-scale woodland habitat, latitude, elevation and prey availability that exists along the transect (Chapter 2). I find that habitat variables strongly affect fledging success but not occupancy or clutch size, whilst occupancy exhibits biogeographic trends, revealing that the relationship between breeding decisions and outcomes differs among habitats and implies that it may be difficult to generalise results from one habitat to others. Next, I aim to identify the environmental aspects which play a role in regulating blue tit reproductive phenology by examining the ability of temperature, tree phenology, invertebrate prey abundance and photoperiod to predict nest initiation and laying dates (Chapter 3). I find that night-time temperature in early spring is the most important predictor of both nest initiation and lay date (slopes ~ -3days/°C) and I suggest that this supports the hypothesis that temperature acts as a constraint on timing rather than a cue. Invertebrate abundance is also a positive correlate of lay date, possibly allowing fine-tuning of timing. This knowledge provides clearer foundations from which to predict future phenological change and possible trophic mismatch in this system. There is the potential that the apparent effect of temperature on blue tit reproductive phenology is indirect and mediated by diet, which is largely undescribed in the period prior to breeding. Therefore, in Chapter 4 I examine how blue tit diet varies across habitat, geography and time, and whether there is a dietary cue utilised to initiate breeding phenology, using data from metabarcoding faeces collected from nestbox-roosting adults in early spring. Geographic variation in diet is substantial, with high site-to-site dietary turnover (β-diversity), as well as high turnover along the elevational and latitudinal gradients studied. Dietary α-diversity (richness) is unaffected by geographical variables, but increases over time, with significant pre-breeding dietary increases in Lepidoptera and Hemiptera signifying a possible cue. In addition, these data provide the most comprehensive next-generation insights into the diet of a wild bird to date and identify 432 prey taxa. Finally, I analyse how biogeographic and habitat variables affect the phenology, abundance and diversity of caterpillars (Chapter 5). Host tree species’ varied significantly in their likelihood of hosting a caterpillar, with oak and willow (Salix sp.) the most likely. Biogeography had less effect on the likelihood of caterpillar occurrence, but elevation delayed peak date by 3.7 days/100m increase. There was also support for the spring caterpillar peak being dominated by a few key species, with over half of all caterpillars identified being of just three of the 62 total species, including winter moth. These findings contribute to understanding how the temporal distribution of caterpillars varies across habitats on the landscape scale. Taken together, the findings of this thesis reveal considerable geographic and habitat variation throughout this system, in both the composition of the food web and the impacts on blue tit productivity, demonstrating why caution must be exercised when extrapolating findings from one location or habitat to others.

Book Summary: Breathtaking photographs and original essays illuminate this tribute to the natural wonders of the Blue Ridge Parkway. The 469 miles of the Parkway run through some of the most magnificent landscapes in the United States, connecting the Shenandoah National Park to the Great Smoky Mountains National Park and these photographs capture the unique beauty of the region. Accompanying the images are heartfelt writings of regional poets and essayists who celebrate their abiding love for the Blue Ridge Mountains.

Thesis (M.Sc.(Chemistry)) -- University of Limpopo, 2018. / Refer to the document / NRF-Sasol Inzalo Foundation

Volumetric muscle loss (VML) is a debilitating injury which results in full or partial loss of function. Current clinical options utilize tissue grafts and bracing to restore function. Tissue graft implantation oftentimes leads to serious complications, some of which end in graft rejection and thereby necessitate further surgeries and procedures. Polymeric scaffolds show promise as scaffolding systems due to their mechanical properties and overall degradation profiles. Scaffolds need appropriate mechanical properties, 10-60 kPa modulus, and overall degradation times, five days to two weeks, to initiate tissue regeneration. Poly(β-amino ester)s (PBAE), a class of synthetic polymers, act as a safe biocompatible material with overall degradation times that are suitable for healing; however, due to harmful ultraviolet light (UV) irradiation from common crosslinking methods, these scaffold systems cannot be synthesized in vivo. This research presents the development and characterization of blue light (BL) crosslinked PBAEs. BL PBAEs showed vastly higher swelling ratios, 300-400% increase; decreased mechanical strength, an average decrease of 877 kPa in compressive modulus and 431 kPa in tensile modulus; and prolonged degradation patterns, 22% average mass retention. BL PBAEs show mechanical properties and degradation profiles that could be used as a skeletal muscle scaffolds.