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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.
31

The role of abscisic acid in grape berry development.

Wheeler, Susan Faith. January 2007 (has links)
Hormones control plant development by coordinating changes in the expression of numerous genes at crucial times in a tissue and organ-specific manner. They have been implicated in controlling various aspects of grape berry development, in particular, the important process of ripening and are used in some crops to control growth and ripening. Abscisic acid (ABA), is associated in grapevine with the response to water stress but may also have a role in berry ripening. We have shown over three seasons that ABA levels in Cabernet Sauvignon berries increase dramatically at veraison, consistent with it being involved either as a trigger for ripening or as a response to the increase in sugars that occurs at this time. Net ABA accumulation doesn't occur until veraison, the decrease in ABA concentration in the first phase of berry development being due to berry expansion. The decrease in ABA that occurs later in development is likely to be due to a combination of catabolism and sequestration into the bound form. The genes crucial to ABA synthesis, 9-cis-epoxycarotenoid dioxygenase (NCED) and zeaxanthin epoxidase (ZEP), were expressed throughout berry development and no clear correlation was found between their levels and that of ABA. Laboratory studies have shown that isolated berries respond to the presence of sucrose through an increase in ABA biosynthesis pathway gene expression (NCED and ZEP). This resulted in de novo synthesis of ABA as inhibition of the carotenoid synthesis pathway by a phytoene desaturase inhibitor prevented ABA accumulation. Replicated field trials clearly showed that ABA treatments can be effective in significantly enhancing ripening when applied in at or near the end of the first period of berry expansion. Colour accumulation in the skins commenced earlier in ABA-treated fruit as did the increase in sugar levels. ABA treatment also advanced the timing of the second phase of berry expansion as it appeared to eliminate the lag phase of berry growth. Taken together these data demonstrate that ABA is likely to play some part in the control of berry ripening and can be used to advance the timing of ripening. Further investigation into the characteristics of ABA-treated fruit will be needed to investigate the compositional character of treated fruit and to gauge its suitability for winemaking. An ability to control the timing of ripening may provide considerable benefits to the wine industry in terms of wine style/quality and for winery scheduling. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1278807 / Thesis (Ph.D.) - The University of Adelaide, School of Agriculture, Food & Wine, 2007.
32

The role of abscisic acid in grape berry development.

Wheeler, Susan Faith. January 2007 (has links)
Hormones control plant development by coordinating changes in the expression of numerous genes at crucial times in a tissue and organ-specific manner. They have been implicated in controlling various aspects of grape berry development, in particular, the important process of ripening and are used in some crops to control growth and ripening. Abscisic acid (ABA), is associated in grapevine with the response to water stress but may also have a role in berry ripening. We have shown over three seasons that ABA levels in Cabernet Sauvignon berries increase dramatically at veraison, consistent with it being involved either as a trigger for ripening or as a response to the increase in sugars that occurs at this time. Net ABA accumulation doesn't occur until veraison, the decrease in ABA concentration in the first phase of berry development being due to berry expansion. The decrease in ABA that occurs later in development is likely to be due to a combination of catabolism and sequestration into the bound form. The genes crucial to ABA synthesis, 9-cis-epoxycarotenoid dioxygenase (NCED) and zeaxanthin epoxidase (ZEP), were expressed throughout berry development and no clear correlation was found between their levels and that of ABA. Laboratory studies have shown that isolated berries respond to the presence of sucrose through an increase in ABA biosynthesis pathway gene expression (NCED and ZEP). This resulted in de novo synthesis of ABA as inhibition of the carotenoid synthesis pathway by a phytoene desaturase inhibitor prevented ABA accumulation. Replicated field trials clearly showed that ABA treatments can be effective in significantly enhancing ripening when applied in at or near the end of the first period of berry expansion. Colour accumulation in the skins commenced earlier in ABA-treated fruit as did the increase in sugar levels. ABA treatment also advanced the timing of the second phase of berry expansion as it appeared to eliminate the lag phase of berry growth. Taken together these data demonstrate that ABA is likely to play some part in the control of berry ripening and can be used to advance the timing of ripening. Further investigation into the characteristics of ABA-treated fruit will be needed to investigate the compositional character of treated fruit and to gauge its suitability for winemaking. An ability to control the timing of ripening may provide considerable benefits to the wine industry in terms of wine style/quality and for winery scheduling. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1278807 / Thesis (Ph.D.) - The University of Adelaide, School of Agriculture, Food & Wine, 2007.
33

The role of abscisic acid in grape berry development.

Wheeler, Susan Faith. January 2007 (has links)
Hormones control plant development by coordinating changes in the expression of numerous genes at crucial times in a tissue and organ-specific manner. They have been implicated in controlling various aspects of grape berry development, in particular, the important process of ripening and are used in some crops to control growth and ripening. Abscisic acid (ABA), is associated in grapevine with the response to water stress but may also have a role in berry ripening. We have shown over three seasons that ABA levels in Cabernet Sauvignon berries increase dramatically at veraison, consistent with it being involved either as a trigger for ripening or as a response to the increase in sugars that occurs at this time. Net ABA accumulation doesn't occur until veraison, the decrease in ABA concentration in the first phase of berry development being due to berry expansion. The decrease in ABA that occurs later in development is likely to be due to a combination of catabolism and sequestration into the bound form. The genes crucial to ABA synthesis, 9-cis-epoxycarotenoid dioxygenase (NCED) and zeaxanthin epoxidase (ZEP), were expressed throughout berry development and no clear correlation was found between their levels and that of ABA. Laboratory studies have shown that isolated berries respond to the presence of sucrose through an increase in ABA biosynthesis pathway gene expression (NCED and ZEP). This resulted in de novo synthesis of ABA as inhibition of the carotenoid synthesis pathway by a phytoene desaturase inhibitor prevented ABA accumulation. Replicated field trials clearly showed that ABA treatments can be effective in significantly enhancing ripening when applied in at or near the end of the first period of berry expansion. Colour accumulation in the skins commenced earlier in ABA-treated fruit as did the increase in sugar levels. ABA treatment also advanced the timing of the second phase of berry expansion as it appeared to eliminate the lag phase of berry growth. Taken together these data demonstrate that ABA is likely to play some part in the control of berry ripening and can be used to advance the timing of ripening. Further investigation into the characteristics of ABA-treated fruit will be needed to investigate the compositional character of treated fruit and to gauge its suitability for winemaking. An ability to control the timing of ripening may provide considerable benefits to the wine industry in terms of wine style/quality and for winery scheduling. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1278807 / Thesis (Ph.D.) - The University of Adelaide, School of Agriculture, Food & Wine, 2007.
34

Ecological and economic services provided by birds on Jamaican Blue Mountain coffee farms /

Kellermann, Jherime L. January 1900 (has links)
Thesis (M.S.)--Humboldt State University, 2007. / Includes bibliographical references (leaves 27-31). Also available via Humboldt Digital Scholar.
35

George Sand et le Berry : paysages champêtres et romanesques /

Caors, Marielle, January 1999 (has links)
Texte remanié de: Th. 3e cycle--Litt.--Paris 4, 1986. Titre de soutenance : Le Berry de George Sand : géographie imaginaire. / Bibliogr. p. 283-288.
36

Embedded Within Landscapes: Agrarian Philosophy and Sustainable Agriculture

Leonard, Evan 08 1900 (has links)
Small-scale, conservation-based agrarianism provides a model for sustainable human habitation within heterogeneous landscapes. Thoreau's Transcendentalism and the historical roots of American Agrarianism are explored as influences for wilderness preservation and the New Agrarian movement. Idealizing a distant wilderness too often means overlooking the ecological and socio-economic environment where people live. Middle landscapes between nature and culture, or between wilderness and cities, can either increase or reduce ecological and social functioning within the landscape matrix. Managing middle landscapes by agrarian principles helps move both nature and culture towards ecological, economic, and social sustainability. This thesis ends with a discussion of agrarian themes, such as supporting decentralized local economies and increasing community connectivity, applied in urban, rural, and wilderness landscapes.
37

Aspects of the biology of the sepiolid squid Rossia Pacifica Berry

Brocco, Steven L. 01 December 2020 (has links)
Aspects of the biology of the sepiolid squid Rossia pacifica Berry were studied from specimens obtained by otter trawling at Cape Lazo Gully and Saanich Inlet, British Columbia. Temperature, salinity, and sediment size at Cape Lazo Gully varied from 7.18°C to 11.00°C, 28.01 °/oo to 30.21 °/oo, and from less than l00μd to over 250μd respectively. Living specimens in the laboratory exhibited color changes from dark red-brown to opalescent grey-green. They did not mimic the color of the substrate. Comparisons of the morphometric indices of R. pacifica with other species of this genus showed differences in some indices but not in others. The arm formula is inconsistent, the most common being 3>2>4>1 and 3>2=4>1. The lower beak differs from that of R. maarosoma by having a "tooth" on its shoulder. In an aquarium Rossia spent most of its time resting on the bottom either in a horizontal position or with the anterior end elevated. The squid usually formed a depression in the sandy bottom to rest in. In some instances they threw sand onto their backs. Fish were caught with the tentacles and held with the arms while being eaten. Stomach analysis revealed that crustacea were present in 86.6% of the stomachs that contained food, while fish were present in 16.6%. Shrimp formed the largest portion of the crustacea in the diet. Bivalve molluscs, squid, and ostracods were occasionally found. Proportions of crustacea to fish in the diet were higher in smaller squid and decreased in larger animals. Seasonal variations in the diet were correlated with the biomass of shrimp in the area where the squid were collected; when a low biomass of shrimp was present the squid had a higher proportion of fish in their diet. The female R. pacifica are slightly larger than the males of the same age and grow to a larger size than do the males. The male and female reproductive systems are described. Gonad indices show that the ovaries and nidamental glands begin to mature when the females have a dorsal mantle length of approximately 24.0 mm. Spermatophores were not found in males smaller than 22 mm mantle length. The proportion of males containing spermatophores was 9% at 22 mm and increased through 17% at 24 mm, 50% at 26 mm to 90% at 28 mm. During mating the male attaches to the female from below by means of his second, third, and fourth pairs of arms. Spermatophores are transferred into the dorsal region of the female's pallial cavity by his dorsal, hectocotylized arms. The sex ratio of males to females found at Cape Lazo Gully was 1.2:1.0. Spawning occurs in the fall with the most active period occurring from August through October. This may be correlated with an increase in the water temperature, during this time. The squid have a life span of one year, at the end of which they mate, spawn, and die. / Graduate
38

Electronic and Transport Properties of Weyl Semimetals

McCormick, Timothy M. 09 October 2018 (has links)
No description available.
39

Evaluation of Berry Extracts on Intestinal Digestive Enzymes and Sugar Transporters

Ohrenberger, Jungbae 11 July 2017 (has links) (PDF)
T2DM is a chronic disease characterized by postprandial hyperglycemia. One of the therapeutic approaches to attenuate hyperglycemia is to inhibit intestinal ɑ-glucosidase enzyme and/or suppress glucose transporters that regulate intestinal glucose transporters such as SGLT1 & GLUT2. Berries rich in polyphenol antioxidants have various health benefits. Although the antidiabetic effects of various berry extracts or berry mixture in pre-clinical and clinical studies, the underlying pathways at the molecular level is still unclear. In this study, we investigated antioxidant and antidiabetic effects of selected berry extracts by determining free radical scavenging activates, Caco-2 intestinal ɑ-glucosidase activity, glucose uptake and the gene expression of ɑ-glucosidase and glucose transporters in Caco-2 cells. Total phenolic contents of berry extracts varied from 28.55 ± 0.06 to 56.15 ± 1.08 gallic acid equivalent (GAE μg/mL) and correlated with antioxidant capacities. Both cranberry extract (CBE) and blackberry extract (BBE) at 200 μg/mL concentration significantly decreased glucose uptake in Caco-2 cells. While mRNA expression and activity of ɑ-glucosidase were inhibited by CBE and BBE, mRNA expression of SGLT1 and GLUT2 was only inhibited by CBE. Moreover, CBE and BBE significantly decreased glucose uptake in the presence of sucrose and AS. Our data suggest that CBE and BBE have different molecular mechanisms in suppressing hyperglycemia and their effects are mediated by inhibiting carbohydrate digestion and absorption.
40

The Impact of Prohexadione-calcium on Grape Vegetative and Reproductive Development and Wine Chemistry

Lo Giudice, Danielle 23 May 2002 (has links)
Prohexadione-calcium (P-ca), as ApogeeTM, was evaluated in 2000 and 2001 for impact to grape vegetative and reproductive development. In 2000, P-ca (250 mg/L) was applied to Seyval, Cabernet Sauvignon, and Cabernet franc (125, 250, and 375 mg/L). P-ca reduced primary shoot growth for all cultivars and decreased cane pruning weight of Seyval. P-ca (375 mg/L) increased Cabernet franc canopy gaps but increased Cabernet Sauvignon lateral leaf area and leaf layer number. P-ca reduced components of yield for all cultivars. In 2001, P-ca (250 mg/L) was applied singularly at weekly intervals to Cabernet Sauvignon clusters and pre and post-bloom to Cabernet franc and Chardonnay canopies. Application at E-L stages 21 and 23 decreased Cabernet Sauvignon fruit set whereas application at E-L stages 26, 27, and 29 reduced berry weight without impacting fruit set. Berry weight reduction correlated to higher color intensity (420+520 nm), anthocyanins, total phenols and phenol-free glycosyl-glucose (PFGG). Cabernet franc vegetative and reproductive development was generally not affected yet treatment increased absorbance at 280, 420, and 520 nm, color intensity, anthocyanins and total phenols. Pre-bloom applications inhibited Chardonnay vegetative development, and reduced components of yield, and fruit chemistry values: hydroxycinnamates, total phenols, flavonoids, PPFG and absorbance at 280 and 320 nm. Post-bloom applications did not affect Chardonnay vegetative or reproductive development, yet increased PFGG. Treatment did not affect Chardonnay wine chemistry but two post-bloom applications increased Cabernet franc wine anthocyanins and total phenols. Wine aroma and flavor triangle difference tests did not indicate significant treatment differences. / Master of Science

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