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Morales, Kendrick Thomas. "Commitment and Radical Religious Sects:An Empirical Examination of the Roots of Terrorism." Miami University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=miami1415986828.
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Lü, Guanghua. "Chemical identification and quality assessment of Radix Angelicae sinensis (Danggui roots)." HKBU Institutional Repository, 2005. http://repository.hkbu.edu.hk/etd_ra/639.
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Rojas, Rosario. "Secondary metabolites of Vernonia gigantea roots : isolation, antimicrobial, chemical and biotransformation studies." Connect to resource, 2000. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1228166792.
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Liu, Jing. "Comparative study on the chemical constituents and bioactivity between radix astragali and radix hedysari." HKBU Institutional Repository, 2011. https://repository.hkbu.edu.hk/etd_ra/1401.
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Sohrabi, Reza. "Biochemical and Functional Characterization of Induced Terpene Formation in Arabidopsis Roots." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/74938.
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Plants have evolved a variety of constitutive and induced chemical defense mechanisms against biotic stress. Emission of volatile compounds from plants facilitates interactions with both beneficial and pathogenic organisms. However, knowledge of the chemical defense in roots is still limited. In this study, we have examined the root-specific biosynthesis and function of volatile terpenes in the model plant Arabidopsis. When infected with the root rot pathogen Pythium irregulare, Arabidopsis roots release the acyclic C11-homoterpene (E)-4,8-dimethylnona-1,3,7-triene (DMNT), which is a common constituent of volatile blends emitted from insect-damaged foliage. We have identified a single cytochrome P450 monooxygenase of the CYP705 family that catalyzes a root-specific oxidative degradation of the C30-triterpene precursor arabidiol thereby causing the release of DMNT and a C19-degradation product named arabidonol. We found that DMNT shows inhibitory effects on P. irregulare mycelium growth and oospore germination in vitro, and that DMNT biosynthetic mutant plants were more susceptible to P. irregulare infection. We provide evidence based on genome synteny and phylogenetic analysis that the arabidiol biosynthetic gene cluster containing the arabidiol synthase (ABDS) and CYP705A1 genes possibly emerged via local gene duplication followed by de novo neofunctionalization. Together, our studies demonstrate differences and plasticity in the metabolic organization and function of terpenes in roots in comparison to aboveground plant tissues.
Additionally, we demonstrated that the arabidiol cleavage product, arabidonol, is further modified by yet unknown enzymatic reactions into three products, which are found in root exudates. We suggested a pathway for their biosynthesis based on precursor feeding experiments and NMR analysis. Although DMNT biosynthetic genes are clustered on chromosome 4 along with several potential modification genes, we did not find a possible role of these genes in the derivatization of arabidonol. Preliminary experimental results using genetic and biochemical approaches for identifying genes involved in the modification steps are also presented. <br />In summary, this study demonstrates an alternative route for volatile terpene formation belowground different from aboveground plant tissues via triterpene degradation and provides evidence for an unexplored triterpene catabolism pathway in Arabidopsis.<br>Ph. D.
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Andersen, Angela Lyn. "Cem Evleri: An Examination of the Historical Roots and Contemporary Meanings of Alevi Architecture and Iconography." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1436301378.
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Johnson, Carter David. "Examination of lignocellulosic fibers for chemical, thermal, and separations properties addressing thermo-chemical stability issues /." [Ames, Iowa : Iowa State University], 2007.
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Faulkner, Briar Lee. "Chemical dependency treatment: An examination of following continuing care recommendations." CSUSB ScholarWorks, 2002. https://scholarworks.lib.csusb.edu/etd-project/2145.
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The purpose of this study was to determine what influence scheduled phone contacts would have on the extent of follow-through of continuing care recommednations by participants after treatment. Continuing care recommendations associated with ongoing sobriety include going to another level of care (individual therapy, group therapy, outpatient treatment), attending twelve-step meetings and communicating with a sponsor. Continuing care recommendations are typically written and referred to as a continuing care plan.
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Muchlinski, Andrew Joseph. "Identification, Characterization, and Functional Analysis of Terpenoid Specialized Metabolism in Switchgrass (Panicum virgatum) and Carrot (Daucus carota)." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/102778.
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Plants produce a large number of specialized or secondary compounds that aid in their reproduction and protection against biotic and abiotic stress. In this work I investigated the metabolism and function of terpenes, the largest class of specialized metabolites, in switchgrass and carrot. Switchgrass (Panicum virgatum L.), a perennial C4 grass of the Tallgrass Prairie, represents an important species in natural and anthropogenic grasslands of North America. Its natural resilience to abiotic and biotic stress has made switchgrass a preferred bioenergy crop. I have investigated the metabolism of terpenes in switchgrass leaves and roots in response to herbivory or defense hormone treatments and the application of drought. With a focus on volatile terpene metabolites, I functionally characterized over thirty genes (terpene synthases, TPSs), of which one third could be correlated with the production and release of volatile monoterpenes and sesquiterpenes that likely function in direct chemical defense or in the attraction of insect predators or parasitoids. Drought stress application caused switchgrass roots to accumulate a larger amount of oxygenated terpenes and presumably non-volatile terpenes, the function of which in direct or indirect drought stress protection requires further investigation. I also examined the metabolic dynamics and role of the monoterpene borneol, which accumulates at high concentrations in the roots of switchgrass and to a lower extent in the roots of the close relative Setaria viridis, in root microbe interactions. Although we demonstrated a successful RNAi based knock down of the borneol terpene synthase TPS04, we found no immediate evidence that borneol significantly modifies bacterial communities in the root. Further studies on Setaria and equivalent RNAi lines in switchgrass will provide more detailed and needed insight to decipher the role of monoterpene accumulation in grasses interactions with mutualists, pathogens, and pests.
In an applied project, I investigated terpene specialized metabolism in carrot (Daucus carota L.) to identify genetic determinants of carrot aroma and flavor. To determine central enzymes which contribute to the terpene component of carrot volatile blends, we first analyzed tissue specific expression patterns of carrot terpene synthase genes (TPS) in the genomic model carrot (cv. DH1) and in roots of four aromatically unique colored carrot genotypes (orange-4943B, red-R6637, yellow-Y9244A and purple-P7262). We selected nineteen key biosynthetic enzymes involved in terpene formation and compared in vitro products from recombinant proteins with native volatile profiles obtained from DH1 and colored carrot genotypes. We biochemically characterized several highly expressed TPSs with direct correlations to major compounds of carrot flavor and aroma including germacrene-D (DcTPS11), (DcTPS30) and -terpinolene (DcTPS03). Random forest analysis of colored carrot volatiles revealed that nine terpene compounds are sufficient for distinguishing the flavor and aroma of raw colored carrots. Interestingly, accumulation of specific terpene compounds rather than chemical diversity is responsible for differences in sensory quality traits in colored genotypes. As accumulations of specific terpene compounds can contribute to the undesired flavor in carrot, our report provides a detailed roadmap for future breeding efforts to enhance carrot flavor and aroma.<br>Doctor of Philosophy
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Sivananthan, Malini. "An examination of the relationship between NO, ABA and auxin in lateral root initiation and root elongation in tomato." Thesis, University of Canterbury. Biological Sciences, 2006. http://hdl.handle.net/10092/1375.
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The length of the primary root and the density of lateral roots determine the architecture of the root. In this thesis the effect of NAA, ABA and the NO donor SNP alone as well as the combination of ABA or NAA with SNP on lateral root development was investigated. The interaction between CPTIO, a NO scavenger, and NAA or SNP is also reported. Following preliminary experiments in which it was observed that the aerial part of the seedling influenced LR growth and that there was a possible inhibitory effect of light on cultured root tips, experiments were conducted with excised roots tips in the dark. NAA was shown to have the potential to initiate LRs across a wide concentration gradient with the total number of LRs and initiated lateral root primordia (LRP) remaining constant across the range of concentrations tested. Over the last decade, nitric oxide (NO), a bioactive molecule, has been reported to be involved in the regulation of many biological pathways. The presence of NO in the system provided via sodium nitroprusside (SNP), promoted LRP initiation based on the NAA concentration gradient; but without changing the total LR initiation, that is LRs plus primordia density remained constant along the concentration gradient of NAA. The absence of LR and LRP in the treatments of CPTIO (a NO scavenger) with SNP or NAA suggests that NO regulates LRP initiation triggered by NAA, which is in agreement with the recent paper published after the commencement of this study (Correa-Aragunde et al., 2006). In agreement with previous studies, ABA inhibited lateral root development by reducing LR density and the number of LRs. The experiments with fluridone, an ABA biosynthesis inhibitor, may indicate that endogenous ABA was at sufficient concentrations in the excised root tips to inhibit primordia initiation. In this study, evidence is presented for the first time to show that SNP can relieve the inhibitory effect of ABA on LR density and number of LRs suggesting the NO, released from SNP, acts downstream of ABA. Overall these data confirm a critical role for NO in LR initiation.
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Boyle, William Ronald. "Getting along with others : an examination of the ethnomethodological roots of preference organization and its relationship to complimenting." Thesis, Aston University, 1997. http://publications.aston.ac.uk/14831/.
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The well-established sociolinguistic literature on complimenting claims that compliments are formulaic (Manes and Wolfson 1981). The purpose of this thesis is to demonstrate that the claim is invalid, to describe an alternative approach to the study of compliments, and to draw on an extensive collection of compliments in order to show that complimenting is a diverse, interactive process. A prerequisite for such work is a means of deciding whether a given utterance is a compliment, but this issue is neglected in the literature. The conversation analytic notion of preference appeared capable of providing this criterion, but research revealed that it was too ill-defined to serve such a purpose. The thesis was, therefore, obliged to clarify the notion of preference before applying it to a study of compliments. The necessary clarification was found in the enthnomethodological roots of conversation analysis, and the thesis provides a clear and consistent means of determining whether utterances are preferred to dispreferred. The criteria used in the determination of preference are applied, in the final chapter, to the study of compliments. The results of the study contrast markedly with those of the sociolinguistic researchers, and they provide significant grounds for rejecting the claim that compliments are formulaic.
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Makame, James. "Sensory and nutritional quality of orange-fleshed sweet potato crisps from roots with varying physico-chemical properties." Diss., University of Pretoria, 2015. http://hdl.handle.net/2263/79276.
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The sensory and nutritional quality of orange-fleshed sweet potato (OFSP) crisps can be optimized by utilizing storage roots with suitable physical and chemical properties. Three root types from the OFSP cultivars Impilo, Bophelo and 199062.1 were evaluated for physico-chemical composition in both raw and deep-fat fried state. Frying significantly lowered the L*, a*, b*, E, h and C colour values for all three root types making the crisps darker compared to raw slices. The dry matter content (%) of Impilo, Bophelo and 199062.1 roots were 19.0, 23.1 and 27.2 respectively. The low dry matter Impilo tubers had the highest glucose content while the high dry matter 199062.1 roots had the lowest, with Bophelo roots intermediate for both the dry matter and glucose content.
Deep-fat frying significantly increased the oil content in the crisps. Crisps from high dry matter roots (199062.1) had significantly lower oil content (25.7 %) compared to those from medium dry matter roots (Bophelo) (32.6 %) and low dry matter roots (Impilo) (35.6 %). This reflects the influence of the physical and chemical properties of the root (e.g. dry matter content) on oil absorption. Medium to high dry matter root (Bophelo and 199062.1) crisps had higher stress and hardness values than low dry matter root (Impilo) crisps based on a compression test. High dry matter root (199062.1) crisps had significantly higher first fracture deformation values compared to low dry matter root (Impilo) crisps, with Bophelo root crisps intermediate.
Crisps prepared from roots of three OFSP cultivars (Impilo, Bophelo and 199062.1) and four other commercial crisp products (butternut, pumpkin, sweet potato and carrot) were further evaluated using Flash Profile (FP) sensory methodology. The sensory profiles of crisps from Bophelo and Impilo roots were more similar and were perceived as more orange and darker, harder, sweeter and less oily compared to 199062.1 crisps. The colour, appearance and flavour of OFSP crisps was influenced by the type and content of sugar in roots, with higher glucose and fructose content in Impilo tubers resulting in darker and sweeter flavoured crisps compared to crisps from Bophelo and 199062.1 roots. The higher β-carotene content of Bophelo roots produced crisps with more intense orange colour, while crisps from 199062.1 roots had the least intense orange colour. OFSP crisps were more orange and darker in colour, and were sweeter relative to commercial samples
High dry matter (199062.1) and high trans-β-carotene (Bophelo) roots can be used to produce value-added crisps with low oil, high trans-β-carotene content and with desirable textural and appearance properties for consumer acceptance. The physico-chemical variations of the OFSP storage root types affect the sensory and nutritional quality of deep-fat fried crisps and this could be exploited in crisp product diversification, in efforts to meet the varied and dynamic sensory expectations of consumers. Using roots with high dry matter (e.g. 199062.1), and high β-carotene content (e.g. Bophelo) in the production of OFSP crisps could optimize product texture, oil content, colour and β-carotene content when compared to root types of low dry matter content (e.g. Impilo). OFSP roots from 199062.1 cultivar may be an ideal choice for cost-effective low fat OFSP crisps with considerable β-carotene content. Low fat crisps would be in tandem with current nutritional thinking on the health benefits of low fat food.<br>Dissertation (MSc)--University of Pretoria, 2015.<br>Food Science<br>MSc<br>Unrestricted
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Huh, Jung-Hyun. "Biochemical, Molecular and Functional Analysis of Volatile Terpene Formation in Arabidopsis Roots." Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/77151.
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Plants produce secondary (or specialized) metabolites to respond to a variety of environmental changes and threats. Especially, volatile compounds released by plants facilitate short and long distance interaction with both beneficial and harmful organisms. Comparatively little is known about the organization and role of specialized metabolism in root tissues. In this study, we have investigated the root-specific formation and function of volatile terpenes in the model plant Arabidopsis.
As one objective, we have characterized the two root-specific terpene synthases, TPS22 and TPS25. Both enzymes catalyze the formation of several volatile sesquiterpenes with (E)-β-farnesene as the major product. TPS22 and TPS25 are expressed in the root in distinct different cell type-specific patterns and both genes are induced by jasmonic acid. Unexpectedly, both TPS proteins are localized to mitochondria, demonstrating a subcellular localization of terpene specialized metabolism in compartments other than the cytosol and plastids. (E)-β-Farnesene is produced at low concentrations suggesting posttranslational modifications of the TPS proteins and/or limited substrate availability in mitochondria. We hypothesize that the mitochondrial localization of TPS22 and TPS25 reflects evolutionary plasticity in subcellular compartmentation of TPS proteins with emerging or declining activity. Since (E)-β-farnesene inhibits Arabidopsis root growth in vitro, mitochondrial targeting of both proteins may fine tune (E)-β-farnesene concentrations to prevent possible autotoxic or inhibitory effects of this terpene in vivo.
We further investigated the role of volatile terpenes in Arabidopsis roots in interaction with the soil-borne oomycete, Pythium irregulare. Infection of roots with P. irregulare causes emission of the C11-homoterpene (or better called C4-norterpene) 4,8-dimethylnona-1,3,7-triene (DMNT), which is a common volatile induced by biotic stress in aerial parts of plants but was not previously known to be produced in plant roots. We demonstrate that DMNT is synthesized by a novel, root-specific pathway via oxidative degradation of the C30-triterpene, arabidiol. DMNT exhibits inhibitory effects on P. irregulare mycelium growth and oospore germination in vitro. Moreover, arabidiol and DMNT biosynthetic mutants were found to be more susceptible to P. irregulare infection and showed higher rates of Pythium colonization in comparison to wild type plants. Together, our studies demonstrate differences and plasticity in the metabolic organization and function of terpenes in roots in comparison to aboveground plant tissues.<br>Ph. D.
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Lee, Sangbeom. "Nondestructive examination of chemical vapor infiltration of 0°/90° SiC/Nicalon composites." Diss., Georgia Institute of Technology, 1993. http://hdl.handle.net/1853/19647.
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Richardson, Denisha. ""Getting to the roots" : a critical examination into the social construction of hair amongst Coloured women living in Cape Town." Master's thesis, University of Cape Town, 2013. http://hdl.handle.net/11427/11081.
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Includes bibliographical references.<br>The purpose of this study is to explore how the social construction of head-hair impacts the lived experiences of a small group of 'Coloured' women living in Cape Town. In the first part, the dissertation argues that colonialism stigmatized the bodies of 'non-whites' as inferior; establishing racist, sexist, and classist perceptions of the human body in comparison to a 'white' imagery. The Apartheid regime in South Africa, in part, heightened these beliefs through social and structural means. All though not static, the influences of these racist ideologies remain prevalent in 21st century South African society and are prevailing in perceptions of hair. The thesis then reviews literature from a Euro-American context –concentrating on the 'black' American experience; to display the ways, in which straight and coarse hair textures are imbued with racist, sexist, and classist perceptions and meanings.
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Jayaram, Saravana Kumar. "A comprehensive chemical examination of methylamphetamine produced from pseudoephedrine extracted from cold medication." Thesis, University of Strathclyde, 2012. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=18133.
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This research evaluates the ability of gas chromatography mass spectrometry (GCMS), isotope ratio mass spectrometry (IRMS) and inductively coupled plasma mass spectrometry (ICPMS) to characterize methylamphetamine hydrochloride synthesised from precursors extracted from proprietary cold medication using three different extraction solvents. Two clandestine routes were utilized in the synthetic phase of the research, (i) Moscow route and (ii) Hypophoshorous route (Hypo). Repetitive batches of samples were prepared and analysed by each analytical technique to provide a robust sample set for data interpretation. Organic impurity analysis was undertaken using a developed and validated GCMS impurity profiling method. The GCMS method discriminated the samples by synthetic route based on the presence of specific target impurities. Carbon, nitrogen and hydrogen stable isotope ratios facilitated the differentiation of samples by route, and precursor source with nitrogen and hydrogen isotopes providing the best results. Inorganic impurities present in the samples were analysed using inductively coupled plasma mass spectrometry (ICPMS). This technique provided meaningful discrimination according to the route and precursor utilized in the synthetic phase. Pattern recognition techniques were applied to the generated data (raw and pre processed) from each of the analytical technique both individually and in combination. Pearson's correlation coefficient, hierarchical cluster analysis, principal component analysis and artificial neural networks (self organizing feature maps) were used to investigate the separation of samples to the individual routes and precursor extracted from the individual solvent systems. The mathematical tools demonstrated that methylamphetamine profiling linking precursors sourced from proprietary grade materials extracted from different solvent systems and synthetic route employed was achievable.
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Vallance, Simon. "Microwave synthesis and mechanistic examination of the transition metal carbides." Thesis, University of Nottingham, 2009. http://eprints.nottingham.ac.uk/10548/.
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This thesis aims to describe the ultra-rapid synthesis of a number of important transition metal carbides as well as investigating their reaction mechanisms. 4 binary systems are discussed; Nb-C, Mo-C, Ta-C and W-C, and work carried out on the ternary system, Nb-Ta-C, is also evaluated. Carbide production was investigated from both the oxide and elemental precursors. Ultra-rapid synthesis has been achieved through the development of a reproducible experimental technique and the investigation into a plethora of reaction variables as well as microwave applicators and powers. This resulted in, specifically within the single mode cavity, the completion of the majority of reactions within 20 s. Further development was then built upon the direct relationship observed between phase fraction results (obtained from Powder X-ray Diffraction (PXD) data), in-situ temperature and ex-situ dielectric property measurements; allowing reaction profiles of the various carbides to be mapped, as well as a crucial understanding of the effects of microwave energy on materials at various temperatures. Powder Neutron Diffraction (PND) was also used to evaluate product purity and the C occupancy of the final products, revealing non-stoichiometry which relates directly to the Tc onset observed for the superconducting transition metal carbides. This, in turn, allowed the trends observed for the ternary carbides to be explained, a linear trend does not exist between Tc and C occupancy. In an effort to develop on the understanding of solid state microwave heating, in-situ reaction monitoring techniques were investigated. Through the use of thermal imaging and high speed photography, the W-C system was observed during the crucial initial stages of the reaction process. The information obtained both corroborated previously collected data and allowed a possible reaction mechanism to be alluded to. The observation of localised heating, prior to the beginning of carbide formation, suggests possible high temperatures far exceeding those observed by optical pyrometry. This could well explain the rapid reaction times as well as suggest an interaction mechanism between carbon, an efficient microwave absorber, and tungsten, a low dielectric loss metal.
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Vaughan, Martha Marie. "Molecular and Functional Characterization of Terpene Chemical Defense in Arabidopsis Roots in Interaction with the Herbivore Bradysia spp. (fungus gnat)." Diss., Virginia Tech, 2010. http://hdl.handle.net/10919/77974.
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Roots and leaves are integrated structural elements that together sustain plant growth and development. Insect herbivores pose a constant threat to both above- and belowground plant tissues. To ward off herbivorous insects, plants have developed different strategies such as direct and indirect chemical defense mechanisms. Research has primarily focused on visible aboveground interactions between plants and herbivores. Root-feeding insects, although often overlooked, play a major role in inducing physical and physiological changes in plants. However, little is known about how plants deploy chemical defense against root herbivores.
We have developed an Arabidopsis aeroponic culture system based on clay granulate, which provides access to root tissue and accommodates subterranean insect herbivores. Using this system, feeding performance and plant tissue damage by the root herbivore Bradysia (fungus gnat) were evaluated. Larval feeding was found to reduce Arabidopsis root biomass and water uptake.
Furthermore, we have characterized a root-specific terpene synthase AtTPS08, which is responsible for the constitutive formation of the novel volatile diterpene compound, rhizathalene, in Arabidopsis roots. Rhizathalene synthase is a class I diterpene synthase that has high affinity for the substrate geranylgeranyl diphosphate (GGPP) and is targeted to the root leucoplast. Expression of the β-glucuronidase (GUS) reporter gene fused to the upstream genomic region of AtTPS08 demonstrated constitutive promoter activity in the root vascular tissue and root tips. Using the established bioassay with Arabidopsis and Bradysia larvae, in aeroponic culture we could show that roots deficient in rhizathalene synthesis were more susceptible to herbivory. Our work provides in vivo-evidence that diterpene compounds are involved in belowground direct defense against root-feeding insects.
Future work is still required to improve our understanding of plant root defense. This study has provided a basis for future investigations on the biochemistry, molecular regulation and defensive function of Arabidopsis root chemicals in interaction with both above- and belowground herbivores (and pathogens).<br>Ph. D.
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Heeb, Thomas Gregory. "Examination of turbulent mixing with multiple second order chemical reactions by the statistical analysis technique /." The Ohio State University, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487267024995615.
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Sadik, Patrick. "Examination of ZnO, CuCrO₂, and CuScO₂ properties for use in transparent electronics and chemical sensors." [Gainesville, Fla.] : University of Florida, 2009. http://purl.fcla.edu/fcla/etd/UFE0024867.
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Bierwisch, Anne [Verfasser], and Franz [Akademischer Betreuer] Worek. "Examination of effectiveness of chemical scavengers as therapeutics in organophosphate poisoning / Anne Bierwisch ; Betreuer: Franz Worek." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2017. http://d-nb.info/1127527835/34.
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Bellamy, Brian Odem. "An examination of prevalent twenty-first century models of community engagement by the black churches." Thesis, University of Exeter, 2016. http://hdl.handle.net/10871/24285.
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This thesis examines three prevalent models of community engagement in the black churches in the United States of America since the year 2000. It will contribute to existing scholarship by identifying theological motivations for community engagement by the black churches, and assessing the extent to which the black churches address and fulfill criteria for advancing liberation delineated from three generations of scholarship in Black Theology. This shall provide theological insight into the continued social relevance of the black churches. Existing scholarship has shown that the black churches historically have engaged the oppressed communities they have served by addressing their secular and social needs in addition to their spiritual ones, with a sense of mission to affirm human dignity and advance social justice. This praxis of liberation through community engagement was necessitated by the oppressive contexts in which the black churches were founded, and has continued in varied ways in tandem with shifts in social location of black people in America. Black church community initiatives have also been marked among three generations of scholars in Black Theology, who have delineated imperatives for which the black churches might engage their communities to fully continue the praxis of liberation in the present. The interrelated aims of this thesis are to discover the theological motivations of black church community engagement agents, and, to consider the extent to which the community engagement initiatives of the black churches of the twenty-first century address critical theological criteria from Black Theology for advancing liberation; each of which will help to illuminate theological implications for the continued social relevance of the black churches. This project requires an examination of contemporary models of black church community engagement in their own social reality. The models of community engagement that are researched are grass-roots movements where black churchpersons use non-violent direct action to advance particular social justice causes, community development corporations where churches filter grant money from the government to create economic opportunities for their local communities, and megachurch initiatives where congregations use the revenue of their large memberships to effect positive change in their communities. Local examples of each model are examined from a grounded theory approach through interviews with clergy and community workers, observations of worship and program activities, and textual analysis of bulletins, websites, and brochures.
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Choi, Seong-Hyun. "Examination of the physio-chemical properties of the human lung surfactant proteins, SP-A and SP-D." Thesis, University of Oxford, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325307.
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Prabawani, Bulan. "An exploratory examination of the factors influencing Indonesian SME's sustainability practices in the textile and chemical industries." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2013. https://ro.ecu.edu.au/theses/576.
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All firms have an impact on the environment in which they operate, for example in the exploration and processing of environmental resources to make a profit. Manufacturing firms, in particular have the potential to pollute the environment with dangerous liquid and solid wastes. Small and medium sized enterprises (SMEs) make a significant contribution to the global economy in both developing and developed countries. Individually, SMEs appear to have little environmental impact, but accumulatively, they have a considerable impact, not only economically but also environmentally. However, managing environment impact is not usually core business for SMEs.
SMEs often suffer from a lack of internal resources and capabilities. For example they can have limited access to credit given their high risk, limited warranty, and lack of managerial experience or track record in managing aspects such as financial, production, and sales data. In terms of environmental issues, SMEs often attract little attention from the media, although government does support environmental management initiatives. Consequently, SME owner managers can be indifferent to, or unable to implement, sustainability practices. Thus, natural resources become objects of exploitation or over exploitation.
Although there are many differences in sustainability definitions, all definitions have at their heart the same objective, that is, how today‘s firms‘ needs are fulfilled such that they do not harm the future. This is evident in definition of sustainability in the business field as ―one that creates profits for its shareholders while protecting the environment and improving the lives of those with whom it interacts‖ (Savitz & Weber, 2006, p.x). Thus, the concept of sustainability is not one which is solely orientated to economic aspects or profit, but also to social and natural aspects, in terms of the triple bottom line (TBL) in undertaking business.
Indonesian SMEs in the manufacturing industry are a source of significant employment; however, they suffer a range of issues. The Asian Development Bank (2005) reported that industrial waste and pollution in Indonesia is out of control, while regulation and enforcement by government is completely inadequate. Studies have shown Indonesia‘s chemical based manufacturers contribute to air pollution, contamination of water sources, and depletion of groundwater through improper and illegal disposal of solid and hazardous waste.
The focus of this thesis is SMEs sustainability: perceived benefits, drivers for and barriers to sustainability. As such this is a study of the natural, social, and economic dimensions that make up the concept of sustainability in relation to Indonesian SMEs. The literature identifies a range of natural, social and economic factors influencing sustainability and these were collated into a model. Eight case studies of SMEs in the Central Java chemical and textile industries were undertaken to refine the measures in the model of sustainability. The overall sustainability of the case study firms was also assessed while hypotheses were constructed as to the relationships between constructs and firms sustainability practices based on firm types and size, as well as industry.
A survey of 215 chemical and textile SMEs was then undertaken to test the refined model and develop a final model. The model was developed using confirmatory factor analysis (CFA) or a measurement model, which included some second order factors for dependent latent variables, and then followed by a structural model which combined each final measurement model. The final model was found to have a high fit (.971 CFI,/df, .041 RMSEA, and .081 RMR) with efficiency as a critical factor influencing sustainability practices.
Overall the study found that sustainability practices were not first priority for these SMEs although they were more inclined towards the present interests in the Sustainable Value framework developed by Hart and Milstein (2003). Indonesian SMEs emphasised resource consumption and civil society issues. In terms of the level of sustainability this group of SMEs were found to have moved ‗beyond the level of legal compliance‘ in terms of their sustainability practices. While Hubbard‘s (2009) Sustainability Balanced Scorecard stresses a balance between the economic as well as the natural and social dimensions of sustainability, this balance was not evident for these Indonesian SMEs. The SME owner managers were also more concerned with the social dimension of sustainability and this was at odds with their perception of the government‘s concern being with the natural dimension of sustainability. However moral mandate was evident as a driver for the natural and social dimensions of sustainability as has been found in other studies of SMEs in developed countries such as New Zealand and the Netherland.
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Lukic, Veronika. "Examination of physiological and morphological parameters of a population of lodgepole pine, Pinus contorta Dougl. spp. latifolia, seedling roots in relation to first year seedling growth." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/mq22629.pdf.
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Barr, Christopher James. "Biochemical Saccharification of Ionic Liquid Pretreated Biomass: an Examination of Treatment Parameters and Enzyme Requirements." University of Toledo / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1372415335.
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Chand, H. R. "Approaches towards the synthesis of polyhydroxylated alkaloids and tetrahydropyrans using carbohydrate scaffolds; chemical transformations of abundant natural products and chemical examination of polyalthia longifolia var. pendula for bioactive molecules." Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 2016. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/2260.
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Hargarten, Paul. "A Cross-Sectional Analysis of Health Impacts of Inorganic Arsenic in Chemical Mixtures." VCU Scholars Compass, 2015. http://scholarscompass.vcu.edu/etd/3788.
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Drinking groundwater is the primary way humans accumulate arsenic. Chronic exposure to inorganic arsenic (iAs) (over decades) has been shown to be associated with multiple health effects at low levels (5-10 ppb) including: cancer, elevated blood pressure and cardiovascular disease, skin lesions, renal failure, and peripheral neuropathy. Using hypertension (or high blood pressure) as a surrogate marker for cardiovascular disease, we examined the effect of iAs alone and in a mixture with other metals using a cross-sectional study of adults in United States (National Health and Examination Survey, NHANES, 2005-2010) adjusting for covariates: urinary creatinine level (mg/dL), poverty index ratio (PIR, measure of socioeconomic status, 1 to 5), age, smoking (yes/no), alcohol usage, gender, non-Hispanic Black, and overweight (BMI>=25).
A logistic regression model suggests that a one-unit increase in log of inorganic arsenic increases the odds of hypertension by a factor of 1.093 (95% Confidence Interval=0.935, 1.277) adjusted for these covariates , which indicates that there was not significant evidence to claim that inorganic arsenic is a risk factor for hypertension. Biomonitoring data provides evidence that humans are not only exposed to inorganic arsenic but also to mixtures of chemicals including inorganic arsenic, total mercury, cadmium, and lead. We tested for a mixture effect of these four environmental chemicals using weighted quantile sum (WQS) regression, which takes into account the correlation among the chemicals and with the outcome. For one-unit increase in the weighted sum, the adjusted odds of developing hypertension increases by a factor of 1.027 (95% CI=0.882,1.196), which is also not significant after taking into account the same covariates. The insignificant finding may be due to the low inorganic arsenic concentration (8-620 μg /L) in US drinking water, compared to those in countries like Bangladesh where the concentrations are much higher. Literature provides conflicting evidence of the association of inorganic arsenic and hypertension in low/moderate regions; future studies, especially a large cohort study, are needed to confirm if inorganic arsenic alone or with other metals is associated with hypertension in the United States.
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Glaab, Fabian [Verfasser], and Werner [Akademischer Betreuer] Kunz. "In-situ examination of diffusion and precipitation processes during the evolution of chemical garden systems / Fabian Glaab. Betreuer: Werner Kunz." Regensburg : Universitätsbibliothek Regensburg, 2012. http://d-nb.info/1023312433/34.
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Hastings, Stephen. "Application of in-situ x-ray diffraction to the examination of the on-line processing of organic fine chemical products." Thesis, Heriot-Watt University, 1999. http://hdl.handle.net/10399/1994.
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Rios, JeÃson Barros. "Chemical study of the roots of Jatropha mollissima ( Pohl ) Baill; identification of phenolic compounds in four species of the genus Anthurium by Liquid Chromatography coupled to Mass Spectrometry." Universidade Federal do CearÃ, 2011. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=6336.
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CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior<br>This work aimed to study the chemical from the root of Jatropha mollissima (Euphorbiaceae), a plant native to northeastern Brazil. In this study we used chromatographic techniques in an attempt to isolate the chemical constituents of hexane and ethanol extracts of the root. Chromatographic treatment of extract allowed the isolation of a long aliphatic chain alcohol called triacontanol, a mixture of the steroids B-sitosterol and stigmasterol and a terpene latirano skeleton called jatrogrossidiona. Also in this work, we investigated the composition of phenolic compounds present in methanol extracts of leaves of four species of the genus Anthurium using HPLC - MS in which it was possible to identify eight phenolic compounds: 6- C- arabinosyl -8- C- glycosyl - apigenin in the leaves of A. lindmanianum; 8-O-ramnosyl-( 1-3)-C-glycosyl - acacetin and 7-O-[6-O-acetylglicosyl(1-2)]ramnosyl-( 1-6 )-glycosyl - acacetin in the leaves of A. andraeanum, 5- caffeoylquinic acid, vitexin, isovitexin and Orientin in the leaves of A. bonplandii and 6- O-ramnosyl-( 1-3)-C-glycosyl-acacetin in the leaves of A. plowmanii. The results for the inhibition of acetylcholinesterase enzyme showed that only the hexane extract of J. mollissima and methanol extract from the leaves of A. andraeanum showed anticholinesterase activity.<br>O presente trabalho teve como objetivo o estudo quÃmico da raiz de Jatropha mollissima (Euphorbiaceae), planta nativa do nordeste brasileiro. Nesse estudo utilizaram-se tÃcnicas cromatogrÃficas na tentativa de isolamento dos constituintes quÃmicos dos extratos hexÃnico e etanÃlico da raiz. O tratamento cromatogrÃfico do extrato hexÃnico possibilitou o isolamento de um Ãlcool de cadeia alifÃtica longa denominado triacontanol, uma mistura dos esteroides B-sitosterol e estigmasterol e um terpeno de esqueleto latirano denominado jatrogrossidiona. Ainda nesse trabalho, investigou-se a composiÃÃo de compostos fenÃlicos presentes nos extratos metanÃlicos das folhas de quatro espÃcies do gÃnero Anthurium atravÃs de CLAE-EM onde foi possÃvel a identificaÃÃo de oito compostos fenÃlicos: 6-C-arabinosil-8-C-glicosil-apigenina nas folhas de A. lindmanianum; 8-O-ramnosil-(1-3)-C-glicosil-acacetina e 7-O-[6-O-acetilglicosil(1-2)]ramnosil-(1-6)-glicosil-acacetina nas folhas de A. andraeanum; Ãcido 5-cafeoilquÃnico, vitexina, isovitexina e orientina nas folhas de A. bonplandii e 6-O-ramnosil-(1-3)-C-glicosil-acacetina nas folhas de A. plowmanii. Os resultados para o teste de inibiÃÃo da enzima acetilcolinesterase mostraram que apenas os extratos hexanico de J. mollissima e metanÃlico das folhas de A. andraeanum apresentaram atividade anticolinesterÃsica.
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Peixoto, Laisla Rangel. "Estudo fitoquímico e biológico da Tacinga palmadora (Britton & Rose) N.P. Taylor & Stuppy (cactaceae)." Universidade Estadual da Paraíba, 2018. http://tede.bc.uepb.edu.br/jspui/handle/tede/3127.
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Previous issue date: 2018-02-20<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES<br>The palmadora, belonging to the family Cactaceae, is a plant popularly known as Palmatoria, Palma or Quipá. The T. palmadora is widely distributed in areas of the Caatinga of the Northeast region of Brazil, the tea of its root being popularly used in the treatment of problems in the urethra. The present study aimed to isolate chemical compounds from the extracts and phases obtained, perform the physicochemical characterization of the plant drug, as well as to investigate biological activities of the roots of the species T. palmadora. After harvesting, the roots were dried and crushed to obtain the vegetable drug. The physicochemical characterization of the plant drug was used to determine the granulometry, density, ash content, moisture content, pH, microstructure (Scanning Electron Microscopy (SEM) and Dispersive Energy (EDS)), Infrared Region Spectroscopy with Fourier Transform (FTIR), Thermogravimetric Analysis (TG) and Differential Thermal Analysis (DTA). The crude ethanol extract (EEB), the nebulized hydroalcoholic extract (EHAN), and the hexane and hexane phases (Hex), Dichloromethane (CH 2 Cl 2), Ethyl Acetate (AcOEt) and Ethanolol (EtOH) were obtained from the root of T.palmadora. In addition, qualitative and quantitative phytochemical screening was performed. Isolation and identification of the chemical compounds were performed by chromatographic and spectroscopic methods, respectively. The toxicological activity against Artemia salina, Determination of Minimal Inhibitory Concentration (MIC) for bacteria and fungi, hemolytic tests and antioxidant activity, using the DPPH (2,2-diphenyl-1-picryl- hydrazyl), Total Antioxidant Activity (AAT) and the Ferric Thiocyanate method. The powder was classified as semi-thin, easy flow, low moisture content and average pH value of 5.58. The data obtained by qualitative phytochemical screening showed positive results for alkaloids and steroids / triterpenoids. TG analysis of the plant drug showed the occurrence of three stages of mass loss. The DTA analysis showed two endothermic and one exothermic events. The phytochemical study of T. palmadora roots resulted in the isolation of 4 compounds, an ester derived from caffeic acid, 5- hydroxy-4 ', 7-dimethoxyflavone, vanillic acid and ethyl palmitate. It was observed that the values of the Lethal Concentration (LC50) of the extracts showed little significant activity (LC50> 1000 μg.mL-1). The extracts AcOEt, EtOH and Hex showed antifungal activity against C. albicans, C. krusei and C. tropicalis. The EtOH extract showed the highest hemolytic activity. The antioxidant activity, as well as the capacity of sequestration of DPPH, the extract AcOEt obtained the best result, where in the concentration of 500 μg.mL-1 obtained an average of 76.44% and for the AAT, the extract AcOEt showed a better result, since the results were similar to the Quercetin standard. T.palmadora has been shown to be a promising species, due to the variety of isolated chemical compounds and important biological activities. Further chemical, pharmacological and toxicological studies should be done to promote knowledge about this plant.<br>Tacinga palmadora, pertencente à família Cactaceae, é uma planta conhecida popularmente como Palmatória, Palma ou Quipá. A T. palmadora é amplamente distribuída em áreas da Caatinga da região Nordeste do Brasil, sendo o chá de sua raiz utilizado popularmente no tratamento de problemas na uretra. O presente estudo teve por objetivo isolar compostos químicos dos extratos e fases obtidas, realizar a caracterização físico-química da droga vegetal, assim como investigar atividades biológicas das raizes da espécie T. palmadora. As raízes após coleta, passaram por processo de secagem e foram trituradas para a obtenção da droga vegetal. Foi realizada a caracterização físico-química da droga vegetal, para determinação da granulometria, densidade, teor de cinzas, teor de umidade, pH, microestrutura (Microscópia Eletrônica de Varredura (MEV) e Energia Dispersiva (EDS)), Espectroscopia na Região de Infravermelho com Transformada de Fourier (FTIR), Análise termogravimétrica (TG) e Análise Térmica Diferencial (DTA). Foi obtido da raiz da T.palmadora o Extrato Etanólico Bruto (EEB), o Extrato Hidroalcólico Nebulizado (EHAN) e os extatos e fases Hexânico (Hex), Diclorometano (CH2Cl2), Acetato de Etila (AcOEt) e Etanolólico (EtOH). Além disso, realizou-se o Screening fitoquímico qualitativo e quantitativo. O isolamento e a identificação dos compostos químicos foram realizados por métodos cromatográficos e espectroscópicos respectivamente. Realizou-se também a atividade toxicológica frente à Artemia salina, Determinação da Concentração Inibitória Mínima (CIM) para bactérias e fungos, testes hemolíticos e atividade antioxidante, utilizando o método de Sequestro do radical DPPH (2,2 -difenil -1- picril –hidrazil), Atividade Antioxidante Total (AAT) e o método de Tiocianato Férrico. O pó foi classificado como semi-fino, de fácil escoamento, baixo teor de umidade e valor médio do pH de 5,58. Os dados obtidos pelo Screening fitoquímico qualitativo mostrou resultado positivo para alcaloides e esteroides/triterpenoides. A análise do TG da droga vegetal mostrou a ocorrência de três etapas de perda de massa. A análise da DTA mostrou dois eventos endotérmicos e um exotérmico. O estudo fitoquímico das raízes de T. palmadora resultou no isolamento de 4 compostos, um éster derivado do ácido caféico, a 5- hidroxi-4',7-dimetoxiflavona, o ácido vanílico e o palmitato de etila.Observou-se que os valores da Concentração Letal Média (CL50) dos extratos apresentaram atividade pouco significante (CL50> 1000 µg.mL^-1 ). Os extratos AcOEt, EtOH e Hex mostraram atividade antifúngica contra á C. albicans, C. krusei e C. tropicalis. O extrato EtOH foi a que apresentou melhor atividade hemolítica. A atividade antioxidante, quanto a capacidade de sequestro do DPPH, o extrato AcOEt obteve o melhor resultado, onde na concentração de 500 µg.mL^-1 obteve uma média de 76,44% e quanto a AAT, o extrato AcOEt mostrou um melhor resultado, visto que os resultados foram semelhantes ao padrão Quercetina. A T.palmadora demonstrou ser uma espécie promissora, pela variedade de compostos químicos isolados e por ter apresentado importantes atividades biológicas. Mais estudos químicos, farmacológicos e toxicológicos devem ser feitos a fim de promover o conhecimento acerca desta planta.
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Ramirez, Cadavid David A. "Development of Processes for the Extraction of Industrial Grade Rubber and Co-Products from the Roots of Taraxacum kok-saghyz (TK)." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1512060296142347.
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Ohanian, Nicholas. "The Examination of Fiber and Breaker Effects on the Rheological and Settling Rate Characteristics of Hydraulic Fracturing Fluids." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1417610323.
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Zhang, Baofang. "Examination Of The Solution Behaviors Of The Giant Inorganic-Organic Amphiphilic Hybrids." University of Akron / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=akron1460369559.
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Ralphs-Thibodeau, Sylvia. "An examination of the impact of Ontario's Patient Restraint Minimization Act, 2001 on the use of physical and chemical restraints among elderly clients in complex continuing care facilities." Thesis, University of Ottawa (Canada), 2007. http://hdl.handle.net/10393/27910.
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In 2001, the Ontario provincial government passed an act to minimize the use of physical and chemical restraints in hospitals. This study utilized data from the Ontario Chronic Care Patient System (OCCPS) from April 1998 to March 2004. Data were analyzed using a simple interrupted time series design with visual and ITSACORR analysis to evaluate whether the act has resulted in a change in prevalence rates of physical restraints among elderly patients in Ontario's complex continuing care beds, both province wide and by facility type (i.e., rural, urban, small, large, private or public).
Provincial legislation to minimize the use of physical restraints was not effective. ITSACORR analysis coupled with visual analysis can be a useful combination of instruments to assess brief interrupted time series although neither method alone is without limitations.
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Williamson, Rhett J. "Qualitative Analysis for the Characterization and Discrimination of Printing Inks." FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/3055.
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Improvements in printing technology and the wide accessibility of advanced printers has resulted in an increase in counterfeiting. Of particular interest to forensic document examiners, ink analysis of security documents has emerged as an important tool for the analysis, comparison, and association of inks to a potential production source. In this study, methods were developed for Py-GC/MS, ATR-FTIR, DART-MS, and MALDI-MS analyses of printing inks of four classes: 78 inkjet inks, 76 toners, 79 offset inks, and 86 intaglio inks in order to generate information on the organic chemical characterization of the inks to determine the ability to associate and discriminate the inks for uses in security document examinations. The suite of analytical techniques evaluated in the study focused on having the following analytical characteristics: 1) rapid analysis time, 2) little-to-no sample preparation, 3) minimal destructiveness to the sample, 4) allow for association of inks with the same source of origin as well as discrimination of inks originating from different sources. As a result of this study, a novel searchable library database of inks was developed for use with each analytical chemical method that allows for data fusion.
Py-GC/MS analysis was used to achieve >63% discrimination of toner inks on the basis of the characterization of polymer degradation products. The combination of a protocol implementing first ATR-FTIR and subsequently DART-MS analysis resulted in >96% discrimination for toners, 95% for inkjet, >92% for offset, and >54% for intaglio. In addition, a case study was performed using DART-MS to illustrate its utility as a tool for ink analysis in document examination. The results of MALDI-MS analyses from two different instruments resulted in >90% discrimination of a subset of all inks by characterizing the colorant molecules present in ink formulations. A study characterizing luminescent compounds present in the formulation of inks in crossed-line intersections was performed using a combination of MALDI-MS, LC-MS, and TLC. Overall, it was shown that the combination of analytical techniques included within this dissertation can provide information on the organic chemical composition of four classes of printing inks, which is useful for the future of document examination.
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Silva, Vinicius Evangelista. "Atributos do solo e desenvolvimento radicular em plantações de eucalipto no Brasil /." Ilha Solteira, 2019. http://hdl.handle.net/11449/182207.
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Orientador: Salatier Buzetti<br>Resumo: O desenvolvimento radicular em plantações de eucalipto tem sido apontado como uma das estratégias cruciais para sua adaptação e crescimento, em especial, em condições tropicais, que possuem solos pobres em nutrientes. Neste contexto, torna-se extremamente importante avaliar o perfil do solo nestas plantações, a luz de uma perspectiva de fornecimento de nutrientes e água para as plantações de eucalipto. Tendo isto em vista, especificamente nesta tese, dois trabalhos foram conduzidos para avaliar os atributos do solo e o desenvolvimento radicular em plantações de eucalipto no brasil, a saber: 1) Disponibilidade de Água no Solo em Plantios de Eucalipto em uma Cronossequência, e suas Relações com a Produtividade e Densidade Básica da Madeira e suas Estimativas Através de Redes Neurais Artificiais no Brasil; 2) Padrões e Distribuição Vertical dos Atributos do Solo na Plantação de Eucalipto no Brasil. A rede experimental completa possui 34 experimentos plantados em um gradiente climático no Brasil e 2 locais no Uruguai, com 36 locais experimentais no total. Avaliaram-se sítios desde baixo incremento médio anual (13,7 m³ ha-1 ano-1, 61% abaixo da média nacional de produtividade), até sítios com elevada produtividade com IMA de 67,2 m³ há-1 ano-1 (92% acima da média nacional de produção de madeira). No trabalho 1, avaliaram-se14 experimentos, e no trabalho 2, 4 experimentos, todos eles ao longo de um forte gradiente climático no Brasil. No caso do trabalho 1 foram avaliados atributos... (Resumo completo, clicar acesso eletrônico abaixo)<br>Abstract: The root development in eucalyptus plantations has been pointed out as one of the crucial strategies for their adaptation and growth, especially in tropical conditions, which have nutrient poor soils. In this context, it is extremely important to evaluate the soil profile in these plantations, considering a nutrient and water supply perspective for eucalyptus plantations. With this in mind, specifically in this thesis, two studies were conducted to evaluate soil attributes and root development in eucalyptus plantations in Brazil, namely: 1) Availability of Soil Water in Eucalyptus Plantations in a Chronosequence, and their Relationships with the Productivity and Basic Density of Madeira and its Estimates through Artificial Neural Networks in Brazil; 2) Patterns and Vertical Distribution of Soil Attributes in Eucalyptus Plantation in Brazil. The complete experimental network has 34 experiments planted in a climatic gradient in Brazil and 2 sites in Uruguay, with 36 experimental sites in total. Sites were evaluated from low average annual increment (13.7 m³ ha-1 year-1, 61% below the national average of productivity), to sites with high productivity with an IMA of 67.2 m³ ha-1 year -1 (92% above the national average of wood production). In work 1, 14 experiments were evaluated, and in the work 2, 4 experiments, all of them along a strong climatic gradient in Brazil. In the case of work 1, physical attributes of the soils (clay, silt, total sand, field capacity, permanent wiltin... (Complete abstract click electronic access below)<br>Doutor
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Peccoux, Anthony. "Molecular and physiological characterization of grapevine rootstock adaptation to drought." Thesis, Bordeaux 2, 2011. http://www.theses.fr/2011BOR21864/document.
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Dans le contexte du changement climatique, les prédictions réalisées mettent en évidence une altération de la disponibilité en eau dans de nombreuses régions viticoles ; ce qui, conjointement à l’augmentation de la population mondiale et la diminution des terres agricoles, va accroître la compétition pour l’utilisation des ressources hydriques. Par conséquent, améliorer l'adaptation à la sécheresse de la vigne est un des enjeux majeurs des prochaines années. Pour cela, une adaptation des pratiques culturales peut être proposée, en particulier le choix pertinent du matériel végétal et notamment du porte-greffe.Dans ce travail, le rôle du porte-greffe vis-à-vis de la réponse de la vigne greffée à la contrainte hydrique a été étudié, en utilisant des approches écophysiologiques, moléculaires et de modélisation. Des expériences ont été réalisées en conditions contrôlées afin d’étudier l’effet du déficit hydrique à court et long terme sur les réponses de différents porte-greffes greffés avec le même scion.Le modèle écophysiologique a démontré que les porte-greffes affectent l'ouverture stomatique du greffon par des processus coordonnés incluant les caractéristiques racinaires, les signaux hydrauliques et les signaux chimiques lors d’un déficit hydrique à court terme. La conductance stomatique, le taux de transpiration et la conductance hydraulique des feuilles ont été plus élevés en conditions irriguées et de stress hydriques modérés chez le génotype résistant à la sécheresse (110 Richter) par rapport au génotype sensible à la sécheresse (Vitis riparia cv. Gloire de Montpellier). Nous avons identifié plusieurs paramètres génétiques impliqués dans le contrôle de la régulation stomatique. Des différences d’architecture racinaire et de conductivité hydraulique des racines ont été identifiées entre les porte-greffes.Le déficit hydrique à long terme a entrainé des réponses adaptatives différentes entre les porte-greffes. Le génotype tolérant la sécheresse a induit une modification du diamètre des vaisseaux du xylème de la partie apicale de la racine en réponse au déficit hydrique modéré tandis que le génotype sensible n'a pas présenté de différence par rapport au contrôle. L’analyse transcriptomique des racines a identifié des gènes spécifiques aux différents génotypes, qui sont régulés en fonction du niveau de déficit hydrique. La comparaison entre les niveaux de stress et les génotypes a identifié 24 gènes intervenant dans l’interaction « traitement × génotype ». Ces gènes sont majoritairement impliqués dans le métabolisme des lipides et de la paroi cellulaire. Des courbes de réponse au déficit hydrique spécifiques aux différents génotypes ont été observées. La protection contre les dommages liés aux stress oxydatifs induits par le stress hydrique semble être un mécanisme important chez le porte-greffe résistant à la sécheresse. Le génotype sensible semble répondre au déficit hydrique par une modification des propriétés de la paroi cellulaire de la racine<br>Climate change raises concerns about temporal and spatial water availability in many grape growing countries. The rapidly increasing world population and the scarcity of suitable land for agricultural food production, together with a changing climate, will increase competition with grape-producing areas for the use of land and resources. Consequently, other practices that can potentially improve water management of vineyards and water acquisition by grapevines need to be considered. Aside from canopy systems and their management, the choice of plant material is a key issue. Therefore, in the present work, the role of different rootstocks, regarding their tolerance to drought, was investigated for their potential effects on i) water uptake, ii) water transport and iii) shoot water use, using a combination of ecophysiological, modelling and transcriptomic approaches. Experiments were conducted under controlled conditions to decipher short and long term responses to drought of different rootstocks grafted with the same scion. An ecophysiological model was used to investigate the roles of rootstock genotypes in the control of stomatal aperture. Long-term steady state water-deficit conditions were used to examine the responses of i) whole plant growth, root anatomy and hydraulic properties and ii) transcriptome remodelling in the roots.Our model showed that rootstock affect stomatal aperture of the grafted scion via coordinated processes between root traits, hydraulic signals and chemical signals. Stomatal conductance, transpiration rate and leaf-specific hydraulic conductance were higher and better maintained under well-watered and moderate water-deficit conditions in the drought-tolerant genotype (110 Richter) compared to the drought-sensitive one (Vitis riparia cv. Gloire de Montpellier). We identified several genotype-specific parameters which play important roles, like root-related parameters, in the control of stomatal regulation. Additionally, root system architecture and root hydraulic properties are important constitutive traits identified between rootstocks.Long-term water-deficit induced genotype adaptive responses in the roots were evaluated. The drought-tolerant genotype exhibited a substantial shift in root tips xylem conduit diameter under moderate water-deficit while the drought-sensitive genotype did not respond. Transcriptomic analysis identified genotype-specific transcripts that are regulated by water-deficit levels. The comparison between stress levels and genotypes identified 24 significant genes in “treatment×genotype” interactions, most of them were involved in lipid metabolism and cell wall processes. These genes displayed genotype-specific water-deficit response curves. Protection against drought-induced oxidative damage was found to be an important mechanisms induced by the drought-tolerant rootstock, while the drought-sensitive one responds to water-deficit by modification of cell wall properties
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Le, Calvar Marc. "Contribution de la spectrométrie photoélectronique (X. P. S. ) et de spectroscopies optiques (50000-400 cm(-1)) à l'étude de l'oxydation du nickel, du chrome et d'un alliage nickel-chrome." Rouen, 1989. http://www.theses.fr/1989ROUES012.
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Aspects théoriques et expérimentaux de la diffusion et de la réflexion spéculaire de la lumière dans le cas des systèmes oxydes de nickel/nickel et oxydes de chrome/chrome. Développement dans le domaine infrarouge d'un modèle de calcul permettant d'interpréter les spectres (variation des paramètres: épaisseur de la couche d'oxyde, angle d'incidence). Application a un alliage Ni 80-Cr 20 de ces techniques de spectrométrie optiques ainsi que de la spectrométrie de photoélectrons en association avec l'érosion ionique pour l'analyse de la composition des couches oxydées et l'étude du mécanisme d'oxydation
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Drhourhi, Allal. "Croissance en phase vapeur par flux force : application aux depots de monocristaux de tib::(2) en systeme ouvert et films de ni en systeme ferme." Clermont-Ferrand 2, 1986. http://www.theses.fr/1986CLF21036.
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Elaboration par depot chimique et transport chimique en phase vapeur des monocristaux tib::(2). Comparaison entre les deux methodes. Developpement d'un plan de travail pour obtenir des depots reproductibles. Etude du systeme ni/nio::(4) en tube scelle. Comparaison avec le systeme ouvert. Analyse du transport des flux. Elaboration du modele du transport des flux
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Diemer, Étienne. "Intensification du procédé d’extraction, de purification et de fonctionnalisation des acides caféoylquiniques à partir de coproduits de la culture de l’endive." Electronic Thesis or Diss., Compiègne, 2024. http://www.theses.fr/2024COMP2821.
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La racine forcée d’endive est un coproduit de la culture de l’endive, produit caractéristique du Nord de la France, de la Belgique et des Pays-Bas. Actuellement sous utilisé en méthanisation ou en alimentation animale, ce coproduit contient pourtant des molécules d’intérêts à haute valeur ajoutée : les acides caféoylquiniques. Ces molécules possèdent des activités antioxydantes, anti-inflammatoires et permettent de limiter les maladies du désordre métabolique. Ce travail de thèse vise à intensifier le prétraitement, l’extraction, la purification et la fonctionnalisation des acides caféoylquiniques à partir des racines forcées pour développer de nouvelles molécules bioactives biosourcées potentiellement intéressantes pour le secteur cosmétique et nutraceutique. Une dernière partie de la thèse porte sur l’étude technico-économique du procédé pour estimer sa rentabilité économique en fonction du secteur d’application visé. La première partie porte sur l’effet des prétraitements conventionnels (découpe et séchage) ainsi que l’effet d’un prétraitement électrique par champs électriques pulsés sur les teneurs en acides caféoylquiniques dans la biomasse. L’effet de l’ajout d’une solution antioxydante lors de l’extraction est également étudié. Dans un deuxième temps, une optimisation de l’extraction est réalisée à partir de biomasse sèche et fraiche. L’influence de facteurs tels que la température, le ratio solide/liquide, ainsi que la nature du solvant a été étudiée. De plus, des cinétiques d’extraction ont été tracées pour étudier les paramètres cinétiques à l’aide d’un modèle empirique. La pureté de l’extrait obtenu étant faible, des étapes de purification sont donc nécessaires. Par la suite, les travaux se sont portés sur la purification de l’extrait brut à l’aide de résines macroporeuses ainsi que par extraction liquide/liquide. Pour la purification par résine, un screening de résines est réalisé suivi d’une optimisation des conditions opératoires de purification avec la résine choisie. Des modélisations des phénomènes d’adsorption sont réalisées pour déterminer les étapes limitantes ainsi que la capacité maximale d’adsorption. Pour l’extraction liquide/liquide, un screening de solvants verts est effectué à partir d’un milieu aqueux et hydro-éthanolique puis une optimisation des conditions opératoires avec le meilleur solvant est réalisée. La pénultième partie de la thèse cherche à fonctionnaliser par estérification les acides caféoylquiniques à partir d’une solution modèle puis d’un extrait réel. Les conditions d’estérification sont optimisées pour augmenter la vitesse de réaction ainsi que le taux de conversion. Des esters avec différentes longueurs de chaine sont obtenus et l’activité antioxydante ainsi que les propriétés anti-UV sont étudiées. La fonctionnalisation est par la suite effectuée sur un extrait réel. Une étude technico-économique conclut la thèse permettant d’ouvrir sur des perspectives quant aux conditions nécessaires à l’industrialisation du procédé de valorisation des racines forcées d’endive<br>Forced chicory root is a by-product of Belgian endive culture, a typical crop of northern France, Belgium and the Netherlands. Currently under-utilized in methanation or animal feed, this by-product contains molecules of interest: caffeoylquinic acids. These molecules have antioxidant and anti-inflammatory properties, and a potential for reducing metabolic disorders. This thesis aims to intensify the pre-treatment, extraction, purification and functionalization of caffeoylquinic acids from forced chicory roots to develop new bioactive biosourced molecules of potential interest to the cosmetics and nutraceutical sectors. The final part of the thesis deals with a technico-economical study of the process to estimate its economic profitability in relation to the targeted application sector. The first part focuses on the effect of conventional pretreatments (cutting and drying) and the effect of pulsed electric field pretreatment on caffeoylquinic acid content in biomass. The effect of adding an antioxidant solution during extraction is also investigated. Secondly, extraction optimization is carried out using dry or fresh biomass. The influence of factors such as temperature, solid/liquid ratio and solvent type were studied. In addition, extraction kinetics were performed to study kinetic parameters using empirical models. As the purity of the extract obtained is low, purification steps are needed. The thesis then focused on purifying the crude extract obtained using macroporous resins and liquid/liquid extraction. For resin purification, resin screening was carried out, followed by optimization of the purification operating conditions with the chosen resin. Models of adsorption phenomena are carried out to identify the limiting stages and the maximum adsorption capacity. For liquid/liquid extraction, green solvent screening is carried out on aqueous and hydro-ethanolic media, followed by optimization of operating conditions with the best solvent. The penultimate part of the thesis seeks to functionalize caffeoylquinic acids by esterification, starting with a model solution and then a real extract. Esterification conditions are optimized to increase both reaction speed and conversion rate. Esters with different chain lengths were obtained, and biological activities such as antioxidant activity and anti-UV properties were studied. Functionalization is also performed with real extract. A technico-economic study concludes the thesis, opening up prospects for the industrialization of the forced chicory roots valorization process
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Gougeon, Gilles. "Etude par analyse automatique d'images de la forme de la texture d'alliages al-si." Caen, 1988. http://www.theses.fr/1988CAEN2001.
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Analyse de l'evolution de la macrostruture et de la microstruture des alliages de fonderie aluminium-silicium as7g en fonction de la composition, des conditions de solidification et des traitements thermiques. L'etude de la macrostruture s'est faite a partir de la reconstruction des zones eutectiques en utilisant des transformations morphologiques et en respectant les conditions de la connaissance locale simple. Quantification de la macrostructure a partir des analyses granulometriques et stereologiques. L'analyse de la microstructure est realisee a partir d'une etude globale de la forme des particules, de silicium. Mise au point et etude critique des procedures d'analyse automatique d'images
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Benkaddour, Abdelkhalek. "Proprietes des defauts d'irradiation dans des alliages austenitiques fer-chrome-nickel et des alliages ferritiques fer-chrome : influence de la teneur en chrome." Paris 6, 1987. http://www.theses.fr/1987PA066144.
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Etude par mesure de resistivite electrique, de l'influence de la teneur en chrome sur la production et la migration des defauts ponctuels dans les alliages fe-25%ni-8 a 16%cr(% en poids) et fe-5 a 15%atcr soumis a une irradiation par electrons a 21k. Influence d'un recuit sur ces defauts d'irradiation. Interpretation des resultats par un modele de restauration
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Berroudji, Sid-Ahmed. "Cinétiques de mise en ordre à courte distance et caractéristiques des lacunes et des autointerstitiels dans des alliages [gamma]-FeNiCr." Grenoble 1, 1988. http://www.theses.fr/1988GRE10095.
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Etude des cinetiques de mise en ordre dans les alliages fe::(59)ni::(25)cr::(16) et fe::(9)ni::(75)cr::(16) par mesure de resistivite electrique. Determination des caracteristiques des lacunes et autointerstitiels par les techniques de trempe a l'helium liquide, de mesure de resistivite lors des cycles alternes de chauffage et de trempe ou lors de cycles continus. Evaluation des enthalpies de formation, de migration et d'autodiffusion. Influence de la composition. Analyse des sursaturations dynamiques de defauts lors de l'irradiation. Determination des frequences de saut des autointerstitiels et de leur enthalpie en fonction de la composition chimique
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Renaud, Gilles. "Ordre chimique et désordre topologique dans les solutions solides AuNi : étude par résistivité et par absorption et diffusion du rayonnement synchrotron X." Grenoble 1, 1988. http://www.theses.fr/1988GRE10134.
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Caracterisation precise de la tendance a l'ordre a courte distance dans le monocristal au::(80) ni::(20): l'alliage est aleatoire en premier voisin, mais il existe une faible tendance a l'homocoordination en second voisin. Determination dans tout le domaine de composition des valeurs des trois distances moyennes partielles ainsi que de la largeur et de l'asymetrie de leur distribution. Mesure de l'effet de coeur dans les alliages dilues. Simulation par ordinateur des distorsions du reseau. Evaluation selon un modele harmonoque de l'energie elastique
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Chung, Shih-Hui, and 鍾世惠. "Chemical constituents from the roots of Cinnamomum subavenium." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/53433290352521734696.
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碩士<br>高雄醫學大學<br>藥學研究所<br>97<br>Lauraceae was obtained in cold methanol extract of the roots of Cinnamomum subavenium Miq. The filtrate was concentrated in vacuum to remove solvent. Then the extract was applied to TLC (thin layer chromatography), for purification to give pure compounds. The nuclear magnetic resonance experimental analysis was used to identify its components. We isolated seven compounds from the roots of Cinnamomum subavenium. including isoobtusilactone A (1)、obtusilactone A (2)、eugenol (3)、myristicin (4)、1-methoxy-2,3-methylenedioxycinnamyl alcohol (5)、β-sitosterol (6) and stigmasterol (7).
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CHEN, HUEI-CHING, and 陳惠卿. "Chemical Constituents from the Roots of Michelia Crassipes." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/wm9k7z.
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碩士<br>輔英科技大學<br>保健營養系碩士班<br>107<br>Michelia crassipes belongs Magnoliaceae species, which is an evergreen small tree or shrub with a height of 2-5 meters and a bark gray-brown. The place of originating in northern Guangdong, southern Hunan, and northeastern Guangxi. It was introduced from the southern part of mainland China in 1661, mostly concentrated in northern Taiwan or Yilan. The flowers in the four seasons are open, smelling like wine or apple fragrance, and the color of the flowers is purple-red, which makes people feel very comfortable and can increase people's visual effects. Mature flower buds can be refined into essential oils. In this study, the composition from the roots of the M. crassipes was studied by column chromatography. There are six compounds was isolated from the methanol extract of M. crassipes: Costunolide (1), 11,13-Dehydrolanuginolide (2), Liriodenine (3), (+)-Pinitol (4), β-Sitosterol (5) and Stigmasterol (6). Those were isolated from the plant for the first time. All of the above compounds were identify by nuclear magnetic resonance spectroscopy its composition and structure.
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Chang, Ning-Shin, and 張寧馨. "Chemical and Bioactive Constituents from the Roots of Solanum erianthum." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/hggp5v.
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Chen, Yu-Wei, and 陳昱緯. "Chemical and Cytototoxic Constituents from Roots of Formosan Cryptocarya concinna." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/68248671618861464085.
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碩士<br>高雄醫學大學<br>天然藥物研究所碩士班<br>94<br>Abstract
Cryptocarya concinna Hance (syn.: Cryptocarya konishii Hayata ex Kawakami; Lauraceae) are medium-sized evergreen trees, which distributed in South China and Taiwan. In a series of cytotoxic screening-program study on Formosan plants, C. concinna was one of the active species. The bioassay-directed fractionation of the active chloroform-soluble part from its roots led to the isolation of seventeen compounds, including five chalcones: cryptocaryone (1), infectocaryone (2), infectocaric acid (135), 2`,4`-dihydroxy-6`-methoxychalcone (143), kuzichalcolactone (18), eight flavanones: the mixture of cryptocaryanone A (3) and cryptocaryanone B (4), 7,8-dihydro-7-hydroxycryptocaryanone (136), 7,8-dihydro-7-methoxycryptocaryanone (137), cryptoconcinic acid (138), kurzichalcolactone A (14), chalcocaryanone C (11), pinocembrin (133); one phenylpropanoid: cinnamic acid (139), one trans-stilbene: pinosylvin (140), one aliphatic acid: lauric acid (141); one steroid: ??-sitosterol (142), respectively. The structures of these compounds were elucidated by spectroscopic interpretations.
Among these isolates, infectocaric acid (135), 7,8-dihydro-7- hydroxycryptocaryanone (136), 7,8-dihydro-7-methoxycryptocaryanone (137) and cryptoconcinic acid (138) are new compounds. Furthermore, cryptocaryone (1), the mixture of cryptocaryanone A (3) and cryptocaryanone B (4) showed significant cytotoxicity against MCF-7, NCI-H460 and SF-268 cancer cell lines, respectively.