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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Antioxidant properties of spaghetti and infant cereals and characterization of major phenolic compounds by LC/MS analysis

Hirawan, Rhanissa 08 April 2011 (has links)
The present study investigated the antioxidant properties of commercial regular- and whole- wheat spaghetti. The antioxidant properties comprise the total phenolic content, DPPH radical scavenging activity, oxygen radical absorbance capacity. The contents of ferulic acid, C-glycosyl flavones and SDG were measured by using LC/MS techniques. Whole wheat spaghetti showed significantly higher TPC and ORAC. The contents of ferulic acid, C-glycosyl flavones and SDG were significantly higher in whole wheat spaghetti. The TPC was found to decrease 48 – 78% after cooking. The results showed that consumption of whole grain is strongly recommended. The present study also compared the antioxidant properties of commercial infant cereals. Purple wheat and red rice were used in making home-made and lab-made infant cereals. Pigmented infant cereals showed higher TPC, total anthocyanin content (TAC) and ORAC then brown rice and commercial ones. Anthocyanins were found only in purple wheat while a C-glycosyl flavone was found at higher levels in purple wheat than in red rice samples. Home-made samples did not show significant differences in TPC, TAC and ORAC with lab-made ones; however, the contents of anthocyanins and C-glycosyl flavones were significantly different. Home-made purple wheat infant cereals showed higher cellular antioxidant activity (CAA) than lab-made purple wheat, red rice and commercial ones. Whole purple wheat holds potential to improve the antioxidant properties of infant cereals.
72

Identification and Antioxidant Properties of Phenolic Compounds during Production of Bread from Purple Wheat Grains and Investigation of Bread Extracts after Simulated Gastrointestinal Digestion

Yu, Lilei 27 October 2014 (has links)
Content of free- (FPC) and bound- phenolics (BPC) significantly (p<0.05) increased during mixing, fermenting and baking. Bread crust and crumb contained the highest FPC and BPC, respectively. Antioxidant activities (AOA) followed the trends of their respective phenolic contents. HPLC analysis demonstrated that different phenolic acids showed various responses to the bread-making process. Total anthocyanin content (TAC) was significantly (p<0.05) reduced through mixing and baking, but fermentation elevated the levels. Anthocyanin extract of purple wheat exerted higher AOA than those of common wheat. Digested purple wheat extracts after in-vitro digestion demonstrated significantly (p<0.05) higher AOA than common wheat. During in-vitro testing, extracts exhibited concentration-dependent effects, while the use of different cell lines exhibited varying levels of cellular antioxidant and pro-oxidant properties. Purple wheat demonstrated higher cytoprotectivity and cellular AOA than those of common wheat. Our findings suggest that purple wheat has the potential to act as functional food in bakery products.
73

Antioxidant properties of spaghetti and infant cereals and characterization of major phenolic compounds by LC/MS analysis

Hirawan, Rhanissa 08 April 2011 (has links)
The present study investigated the antioxidant properties of commercial regular- and whole- wheat spaghetti. The antioxidant properties comprise the total phenolic content, DPPH radical scavenging activity, oxygen radical absorbance capacity. The contents of ferulic acid, C-glycosyl flavones and SDG were measured by using LC/MS techniques. Whole wheat spaghetti showed significantly higher TPC and ORAC. The contents of ferulic acid, C-glycosyl flavones and SDG were significantly higher in whole wheat spaghetti. The TPC was found to decrease 48 – 78% after cooking. The results showed that consumption of whole grain is strongly recommended. The present study also compared the antioxidant properties of commercial infant cereals. Purple wheat and red rice were used in making home-made and lab-made infant cereals. Pigmented infant cereals showed higher TPC, total anthocyanin content (TAC) and ORAC then brown rice and commercial ones. Anthocyanins were found only in purple wheat while a C-glycosyl flavone was found at higher levels in purple wheat than in red rice samples. Home-made samples did not show significant differences in TPC, TAC and ORAC with lab-made ones; however, the contents of anthocyanins and C-glycosyl flavones were significantly different. Home-made purple wheat infant cereals showed higher cellular antioxidant activity (CAA) than lab-made purple wheat, red rice and commercial ones. Whole purple wheat holds potential to improve the antioxidant properties of infant cereals.
74

Potential of Smicronyx spp. (Coleoptera:Curculionidae) as biological control agents of Striga hermonthica (Del) Benth and Alectra vogelii Benth (Scrophulariaceae) in Burkina Faso (West Africa)

Otoidobiga, Lenli Claude. January 1997 (has links)
The potential of Smicronyx umbrinus Hustache and Smicronyx guineanus Voss (Coleoptera: Curculionidae) as biocontrol agents of Striga hermonthica (Del) Benth was investigated at both population levels of Striga and Smicronyx spp. in the field in Burkina Faso. High population levels of Smicronyx spp. resulted in higher percentages of seed-pod galls although the weevils' adult populations decreased during S. hermonthica seed capsule production. Smicronyx spp. were observed galling Striga aspera (Willd) Benth capsules ca. 60 days before S. hermonthica emerged in sorghum fields. The weevils also galled S. hermonthica stems at soil level and Sm. umbrinus was found to be the main species causing this symptom. Smicronyx spp. also galled Alectra vogelii Benth stems, Smicronyx dorsomaculatus Cox being the main species attacking this parasitic weed. Another Smicronyx species not yet described was collected on A. vogelii. Stem galls appeared to be more effective nutrient sinks than fruit galls. The weevils alone did not have sufficient impact to be considered successful biocontrol agents for S. hermonthica but they could contribute to an integrated control strategy against Striga. Smicronyx spp. have a good potential as biocontrol agents for A. vogelii.
75

An inaugural dissertation on the use of Digitalis purpurea, or purple foxglove, in the cure of diseases : submitted to the public examination of the faculty of physic under the authority of the trustees of Columbia College, in the State of New-York ; the Right Rev., Benjamin Moore, D.D. President ; for the degree of doctor of physic, on the 4th of May, 1802 /

Brower, Jacob Vredenburgh, Swords, James, Swords, Thomas, January 1802 (has links)
Thesis (Dr. of Physic)--Columbia College, 1802. / Signatures: [A]⁴ B-C⁴. Film 633 reel 16 is part of Research Publications Early American Medical Imprints collection (RP reel 16, no. 279). DNLM
76

Produção de biomassa por Rubrivivax gelatinosus em efluente de abatedouro avícola utilizando métodos industriais /

Paulino, Clariana Zanutto. January 2006 (has links)
Orientador: Elisa Helena Giglio Ponsano / Banca: Maria Josefa Santos Yabe / Banca: Manoel Garcia Neto / Resumo: Rubrivivax gelatinosus é uma Bactéria Púrpura Não Sulfurosa (BPNS) que apresenta a capacidade de realizar a biorremediação de águas residuárias e, ao mesmo tempo, produzir pigmentos carotenóides. Os objetivos desse estudo foram a caracterização da curva de crescimento da bactéria no efluente de abatedouro avícola em nível de 1% (v/v) de inóculo, a determinação da produtividade do processo de obtenção de biomassa e a avaliação da capacidade de remoção da Demanda Química Oxigênio do processo. R. gelatinosus apresentou maior crescimento no oitavo dia de cultivo (Absorvância = 1.177; peso-seco = 0.18 g l-1), produtividade de 0.085 g biomassa (massa seca) l-1 d-1 e uma redução de 91% na DQO do efluente de abatedouro avícola. / Abstract: Purple nonsulfur phototrophic bacterium Rubrivivax gelatinosus was used to promote the bioremediation of poultry slaugtherhouse wastewater. The aims of this study were to characterize the bacterium growth curve in that effluent at 1% (v/v) inoculum level, to determine the productivity of the biomass production process and to evaluate the Chemical Oxygen Demand removal activity of the process. R. gelatinosus showed the highest growth on the 8th day of cultivation (Absorbance = 1.177; Dry weight = 0.18 g l-1), productivity was around 0.085 g biomass (dry weight) l-1 d-1 and the COD of the poultry slaugtherhouse wastewater decreased in 91%. / Mestre
77

Extending Spectrophotometric pHT Measurements in Coastal and Estuarine Environments

Douglas, Nora Katherine 06 April 2018 (has links)
Nearshore and estuarine environments play a vital role in the cycling of carbon, but the effects of ocean acidification in estuarine waters have not been studied as extensively as in the open ocean. One reason for this is the limitation of pH measurement capabilities in low-salinity waters. Typically, pH in these environments has been measured using potentiometric methods that are subject to uncertainties on the order of 0.01. Spectrophotometric methods for measuring pHT offer precision and accuracy superior to those of potentiometric methods. However, previous characterizations for purified sulfonephthalein indicators, used for marine spectrophotometric measurements, are not applicable to estuarine salinities. Some estuarine datasets using unpurified indicators exist, but the presence of dye impurities affects the accuracy of these characterizations. Colorimetric impurities are known to interfere with absorbance measurements and can cause errors in pH on the order of 0.02. In this work, a mathematical model has been developed to correct spectrophotometric pHT determined with unpurified m-Cresol Purple (mCP), the indicator used most widely for these measurements. The model accounts for absorbances of colorimetric impurities that interfere with absorbance by mCP. This corrective approach brings measurements made using unpurified mCP in synthetic solutions of 0.7 M NaCl into better agreement with those made using purified mCP: within ±0.004 pH units for all six indicators tested at pHT ≤ 8.0. The model is useful for both (a) research groups currently using unpurified mCP to measure pHT, and (b) retrospective correction of historic pHT datasets collected using unpurified mCP. The correction requires only that a small sample of the unpurified mCP is saved for a single-point test at high pHT (~12), and that historic absorbance measurements are archived for subsequent correction. The principles of the corrective model were applied to an historic calibration of the mCP dissociation constant (KI) at 0 ≤ S ≤ 40 and T = 298.15 K using unpurified indicator. After correction of absorbances for dye impurities, recalculation of KI was performed, and the recalculated values were combined with mCP KI data for freshwater and seawater. The combined dataset was then refitted as a function of S and T. The resulting model is representative of mCP behavior across 0 ≤ S ≤ 40 and 278.15 ≤ T ≤ 308.15 K and produces p(KIe2) values that are within ±0.004 of p(KIe2) values from previously published purified mCP calibrations. This refitting approach was also applied to pHT determinations made with Thymol Blue (TB) and Cresol Red (CR), two sulfonephthalein indicators that have been previously used in waters outside the indicating range of mCP. The models, which were of the same form as the estuarine p(KIe2) model for mCP, performed approximately as well as the mCP model: with the exception of one high-salinity, high-temperature TB datum, all residuals were within ±0.0043 of the previously published TB and CR calibrations. Finally, an internal consistency analysis was performed using carbon chemistry data collected during two recent coastal ocean acidification research cruises. For pHT measurements performed during both cruises, purified mCP was used, and corresponding measurements of total alkalinity (TA) and dissolved inorganic carbon (DIC) were conducted. Both cruises included excursions into the Columbia River, where low salinities prevent usage of the marine p(KIe2) model for purified mCP. The Columbia River samples provided the opportunity to evaluate the internal consistency of pHT measurements made in low-salinity waters using the refitted estuarine p(KIe2) model. Although internal consistency agreement in the estuarine range is poor compared to marine measurements, pHT calculated using the new estuarine model compared well with pHT calculated using the previously published estuarine mCP model. The poor internal consistency in the estuarine range, even when making state-of-the-art pH measurements, points toward the need for a more robust characterization of the carbonic acid dissociation constants in the estuarine salinity range. This characterization should take into account the contributions of organic acids to total alkalinity in nearshore waters.
78

Effects of photoperiod on molting in the brachyuran crabs, Hemigrapsus nudus (Dana, 1851) and Cancer magister (Dana, 1852)

Sidi, Claude Elie, 1953- 06 1900 (has links)
viii, 61 leaves : ill. ; 28 cm Typescript. (Another copy on microfilm is located in Archives) Thesis (M.S.)--University of Oregon Includes vita and abstract Bibliography: leaves 57-61 University of Oregon theses, Dept. of Biology, M.S., 1980
79

Competitive interactions among three crab species in the intertidal zone

Daly, Gregory Pattengell, 1949- 03 1900 (has links)
xi, 153 leaves : ill. Typescript. (Another copy on microfilm is located in Archives) Thesis (PhD.) -- University of Oregon Includes vita and abstract Bibliography: leaves 145-153 University of Oregon theses, Dept. of Biology, Ph.D., 1981
80

Viabilidade do controle da mancha púrpura e efeitos nos aspectos físicos, químicos e biológicos do solo e na produção do alho pelos microrganismos eficazes

Verzignassi, Jaqueline Rosemeire [UNESP] 01 June 2000 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2000-06-01Bitstream added on 2014-06-13T19:05:00Z : No. of bitstreams: 1 verzignassi_jr_dr_botfca.pdf: 678064 bytes, checksum: 1a9c22b2b6f4814a330b0bfcccb5c204 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Com o objetivo da redução da aplicação de fungicidas na produção de alho, foram estudados os efeitos dos Microrganismos Eficazes (E.M.-4 e E.M.-5) sobre o controle da mancha púrpura, a produção da cultura e as propriedades físicas, químicas e biológicas do solo. Os experimentos foram conduzidos, em condições de campo, por dois e três anos, na Fazenda de Ensino, Pesquisa e Produção da Unesp em São Manuel, SP. O E.M. foi aplicado nos bulbilhos de alho antes do plantio, adicionado ao material orgânico incorporado ao solo e pulverizado nas plantas após incubação ou não com melaço. A utilização do E.M. + melaço (não incubado) não proporcionou controle da doença nos experimentos. No entanto, com a incubação do E.M. + melaço houve redução na severidade da mancha púrpura em um experimento e incremento na emergência e número de folhas verdes por planta em ambos os experimentos. A altura das plantas, superbrotamento, produção, bulbos de maior valor comercial (classes 5+6+7) e as propriedades físicas (densidade do solo, condutividade hidráulica, estabilidade dos agregados, resistência à penetração e infiltração de tinta), químicas e biológicas do solo (conteúdo de polissacarídeos, carbono da biomassa microbiana do solo e atividade da desidrogenase) não foram alteradas pela utilização do E.M. A adição de material orgânico ao solo promoveu maior agregação do solo (estabilidade dos agregados), independentemente dos tratamentos empregados. No entanto, a densidade do solo, a condutividade hidráulica e a resistência à penetração não sofreram alterações com a adição do material orgânico. / With the purpose to reduce fungicides application for garlic production, the effects of Effective Microorganisms (E.M.-4 and E.M.-5) were studied on the control of garlic purple blotch, garlic yield and physical, chemical and biological properties of the utilized planting soil. Experiments were carried out under field conditions, for two and three years, an experimental farm, belonging to São Paulo State University, located in São Manuel, São Paulo, Brazil. E.M. was applied on garlic cloves before planting, additioned to the incorporated organic matter and sprayed on garlic aerial part after incubation or not with molasse. When E.M. plus molasse (not incubated) was utilized the control of purple blotch was not observed in two experiments. However, with the incubation of E.M. with molasse, the results showed a reduction of purple blotch severity in one experiment as well as an increment of seedling emergency and number of green leaves per plant in two experiments. Plant height, bulbil sprouting, yield, bulbs with higher market grades (classes 5+6+7) and soil physical (bulk density, hidraulic conductivity, stable soil aggregates, resistance to soil penetration and tint infiltration) chemical and biological (polyssacharides, carbon of microbial biomass and dehydrogenase content) proprieties were not affected by E.M. utilization. Organic matter addition promoted soil agreggation in all treatments, however, soil bulk density, hidraulic conductivity and resistance to soil penetration was not changed by organic matter addition.

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