• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 606
  • 274
  • 176
  • 173
  • 157
  • 122
  • 77
  • 55
  • 43
  • 39
  • 30
  • 13
  • 13
  • 9
  • 9
  • Tagged with
  • 1983
  • 175
  • 138
  • 130
  • 123
  • 117
  • 116
  • 114
  • 113
  • 111
  • 109
  • 103
  • 98
  • 97
  • 97
  • 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.
671

Telemann’s Psalm 117, Laudate Jehovam omnes gentes, TWV 7:25

January 2019 (has links)
abstract: Abstract   Among Georg Philipp Telemann’s most-performed works is his setting of Psalm 117 (Psalm 116, Vulgate), Laudate Jehovam, TWV 7:25. There are three sources; Telemann’s autograph score (heavily marked and corrected by Telemann’s grandson, Georg Michael), a contemporary set of parts by a copyist, and another set of parts by Georg Michael Telemann based on his corrections to the autograph score. There are currently at least seven editions of this work readily available, none of which fully agrees with the autograph manuscript or original parts. The editions also differ substantially from one another: for example, two of them are in a different key from the others. This clearly points to the need for a new edition. Further, the additions and corrections by Georg Michael Telemann are interesting. These fall into several categories: changes made to correct errors or clarify ambiguities in Georg Philipp Telemann’s original, changes made to reflect performance practice that Georg Philipp might have assumed but that were no longer customary in Georg Michael’s time, adjustments to melody and rhythm that may reflect Georg Michael’s personal taste and preference, and the addition of parts for oboe and viola, along with significant changes to the second violin part that suggest that Georg Michael’s version was intended for performance by a chorus and orchestra, whereas Georg Philipp’s original could be performed as a chamber work, with one singer and instrumentalist per part, or by a larger ensemble. A discussion of the piece, along with scores of both the original version and Georg Michael’s version, provides both scholars and performers with greater insight into this brief but significant work. / Dissertation/Thesis / Doctoral Dissertation Music 2019
672

Interleukin-7 - mediated signaling and its role in the biology of T-cell acute lymphoblastic leukemia : potential targets for therapeutic intervention

Barata, João Taborda January 2002 (has links)
No description available.
673

Dimensionamento de estruturas de suporte flexíveis segundo o Eurocódigo 7

Vieira, Castorina Fernanda da Silva January 1997 (has links)
Dissertação apresentada para obtenção do grau de Mestre em Estruturas de Engenharia Civil, na Faculdade de Engenharia da Universidade do Porto, sob a orientação do Professor Doutor Manuel Matos Fernandes
674

In vitro evaluation of anticancer effect on momordica balsamina linn. leaf extract in human MCF-7 cancer cells

Boshielo, Itumeleng Tania January 2017 (has links)
Thesis (M.Sc. (Biochemistry)) --University of Limpopo, 2017 / Cancer is a broad group of various diseases characterised by unregulated cell proliferation which leads to the formation of tumours (Vickers, 2004). Some tumours remain confined to their site of origin while some gain the ability to spread to other parts of the body, a process known as metastasis (Weiss, 1990). The burden of cancer continues to rise, due to inefficient prevention strategies and serious side effects, as well as the cost of cancer regimens (Sondhi et al., 2010). Medicinal plants represent a reservoir of bioactive compounds that can be useful in the management of cancer with less or no side effects (Wong et al., 2012). The aim of this study was to investigate the anti-cancer effects of M. balsamina leaf extract in breast MCF-7 cancer cells. In this study, M. balsamina leaves powder was extracted using acetone. The biological effect of the extract was assessed on the viability of MCF-7 cells using the MTT assay. The extract’s ability to induce apoptosis was assessed using the Hoechst/propidium iodide dual staining method. Its anti-metastatic potential was investigated by determining its effect on MCF-7 cell migration, attachment and invasion using wound healing, adhesion, invasion assay, respectively. The human apoptosis antibody and human angiogenesis antibody array kits were used to determine the effect of the extract on the expression levels of proteins involved in apoptosis and metastasis, respectively. Treatment of MCF-7 cells with different concentrations of the extract showed a significant decrease in cell viability after 48 h incubation at 10 - 20 µg/ml. The decrease in cell viability was associated with the induction of apoptosis as seen by nuclear condensation and loss of membrane permeability in cells treated with the extract. Inhibition of migration, adhesion and invasiveness of the MCF-7 cells was seen in the treated cells. The extract also modulated proteins implicated in cell apoptosis, adhesion, migration and invasion such as Bcl-2 family of proteins, IGFBP, uPA, MMPs. In conclusion, based on the results, the extract show pro-apoptotic and anti-metastasis potential. Thus M. balsamina can be considered as a potential source of compounds with anti-cancer activity
675

PC7 : une protéase sécrétoire énigmatique ayant une fonction de sheddase et un ciblage cellulaire unique

Durand, Loreleï 04 1900 (has links)
No description available.
676

Sediment budget closure during runoff-generated high flow events in the South Amana sub-watershed, Ia

Denn, Kevin Daniel 01 May 2010 (has links)
Event-based sediment budgets were developed in a small agricultural sub-watershed using radionuclide tracers in conjunction with traditional monitoring techniques. The result of these budgets quantified the flux of material from each sediment source in the sub-watershed. The first step in the study was to quantify the net flux of material through the watershed outlet for runoff events. Results indicated that a pronounced clockwise hysteresis effect occurred during all studied events. The cause of the hysteresis effect was attributed to exhaustion of the upland (i.e., hillslopes and floodplains) sediment source. The hysteresis effect was dampened during an extreme flash flood event that caused overbank flow. This dampening was attributed to an increase in upland sediment mobilization resulting from overbank flow. Results of the event-based monitoring were compared against a previously developed sediment rating curve that assumed a power-law relationship between suspended sediment transport and water flow rates. The results indicate that the power-law relationship grossly under predicted the sediment flux over each runoff event. A tracing technique was utilized to establish the relative contributions from the uplands and the stream channel (i.e., channel banks and bed). This technique used the relationship between the naturally occurring radionuclide tracers 7Be and 210Pbxs to differentiate eroded upland soils from channel-derived sediments in the suspended sediment loads. A simple two end-member unmixing model was used to determine the relative contribution from each source. Results indicate that the upland source was the dominant contributor to the suspended load early in the runoff events, but channel contributions were more prevalent at later stages, reinforcing the conclusion drawn from the hysteresis observation. Further analysis of the results indicated that the uplands contributed the majority of the material to the suspended load because the sediment transport rate during the early stages of the event was much larger than during the later stages. Therefore, watershed managers wishing to minimize non-point source pollution resulting from erosion should first focus their efforts on reducing erosion of upland soils.
677

A COMPARATIVE STUDY OF EQUIVALENT LATERAL FORCE METHOD AND RESPONSE SPECTRUM ANALYSIS IN SEISMIC DESIGN OF STRUCTURAL FRAMES

Shrestha, Santosh 01 August 2019 (has links)
Equivalent Lateral Force Method (ELF) and Response Spectrum Analysis (RSA) are the two most popular methods of seismic design of structures. This study aims to present a comparative study of the two methods using hand-calculated approach as well as computer analysis according to ASCE 7-10 Standards. The two methods have been compared in terms of base shear and story forces by analyzing various models for different number of stories and different support conditions. It was found that ELF gives conservative results in comparison to RSA. This result was more obvious in case of four-story frames. Hence, for structures of increased elevation, the analysis from ELF may not be sufficient.
678

Breeding for Tomato Resistance to Spider Mite <em>Tetranychus urticae</em> Koch (Acari: Tetranychidae)

AL-Bayati, Ammar Sami 01 January 2019 (has links)
Cultivated tomato plants are extremely susceptible to the two-spotted spider mite Tetranychus urticae Koch. Selection for pest resistance is usually a crucial step required to achieve successful genetic resistance transfer from wild into cultivated tomato genotypes. S. habrochaites LA2329, a wild relative of tomato, is highly resistant to arthropods. Its resistance has been attributed to the presence of a high density of type IV and type VI trichomes and abundant production of 7-epi-zingiberene, a sesquiterpene hydrocarbon. The interspecific backcross hybrids used in this research were derived from the cross between the wild relative tomato, S. habrochaites LA2329, and the cultivated tomato, S. lycopersicum ‘Zaofen 2’ (ZH2). This population has been directly selected for type IV trichome density and zingiberene. The arthropod resistance status of the backcross hybrids was unknown when this research was initiated. Thus, the main objective of the research was to verify the transfer of arthropod resistance from S. habrochaites to cultivated tomato. The effects of glandular trichome densities and leaf zingiberene contents on spider mite behavior and biology were also explored. Also, the chemical composition of the trichome secretions in the wild tomato donor is segregating for presence and abundance of sesquiterpenoids related to zingiberene. The bioactivity of these sesquiterpenoids was explored in this research. To evaluate the relative bioactivities of zingiberene alcohol and 7-epizingiberene, extracted from glandular trichomes of Solanum habrochaites accession LA2329, as well as alpha-zingiberene obtained from ginger oil, these were purified by silica gel chromatography and bioassayed with two-spotted spider mites, Tetranychus urticae Koch (Acari: Tetranychidae) using a bean leaf disc bioassay. Zingiberene alcohol was most efficacious and alpha-zingiberene, was least efficacious, while the efficacy of 7-epizingiberene was intermediate. Thus, tomato breeders should consider introgression of the genes responsible for the oxidation of 7-epizingiberene into zingiberene alcohol to potentially improve the spider mite resistance of cultivated tomato. Also, it is possible that this compound may be exploited as eco-biopesticide approach for integrated pest management against a broad spectrum of herbivorous pests. To verify transfer of arthropod resistance, a bioassay utilizing whole leaves was employed. Nine hybrids (BC3F3 and BC3F4) were chosen for this bioassay, based on variation of type IV trichome density and zingiberene concentration among the hybrids. The experiment also included three susceptible and three resistant control plants. Mite responses on some of the hybrids were similar to those on the resistant wild donor parent, S. habrochaites, as indicated by number of leaflet surfaces infested by mites, degree of mite webbing and feeding damage. Egg density on four backcross hybrids was similar to that on the S. habrochaites resistant controls. Based these results, we concluded that resistance had been successfully transferred from the wild accessions to the hybrids by deployment of backcrossing and indirect selection. There was a significant negative correlation of almost all mite behavioral and biological responses with Type IV trichome density and zingiberene content. This bioassay illuminated behavioral variations of mites associated with presence or absence of leaf compounds and glandular trichome densities. Also, the results support the idea that introgression of type IV trichomes and zingiberene has led to effective spider mite resistance. In another bioassay-based experiment to verify transfer of resistance, seven interspecific backcross hybrids (BC3F2), the resistant parent LA2329, and two susceptible cultivated tomato lines, the recurrent parent ZH2 and ‘Small Roma’, were used in thumbtack bioassays. Mite movement was measured by imaging bioassayed leaves at 15, 20, 30, 45, and 60 min intervals. In addition to confirming transfer of spider mite resistance, other objectives included determination of the relative contributions of type IV and VI trichome densities and leaf compounds to mite behavior over time intervals. Our findings confirmed the transfer of mite repellency from the wild resistant parent to advanced backcross hybrids. Several backcross hybrids performed similarly to the wild donor parent, displaying shorter distances traveled on the leaves after 15 and 30 min. The type IV and type VI trichome densities as well as zingiberene contents had a significant positive correlation with the number of spider mites remaining on tack. There was a significant negative correlation of type IV density and zingiberene concentration with the total distance travelled by mites for both the abaxial and adaxial surfaces across most time intervals. Stepwise multiple regression analysis showed that the type IV trichome density was the most critical factor, and zingiberene content was a secondary factor across over most time intervals. T. urticae remained longer on the thumbtack heads and traveled shorter distances on the leaf surface of the wild donor parent LA2329 and the interspecific hybrids compared to S. lycopersicum leaves. These results indicated that introgression of genetic resistance, especially repellence, against spider mite from the wild relative into cultivated tomato varieties has been successfully achieved. In conclusion, trichome type IV and/or zingiberene content has been successfully transferred from the wild relative into interspecific tomato hybrids, and the hybrids show significant adverse impact on spider mite behavior and/or biology in whole leaf and thumbtack bioassays. Type IV trichome density is the most crucial factor in mite deterrence while zingiberene seemed to be a second key factor across most of time durations for both surfaces. Collectively, several backcross hybrids had similar leaf characteristics to the S. habrochaites LA2329, also may be a potential source of resistance to other insect pests.
679

Regulation of cancer-specific miRNAs by MDA-7/IL-24

Scheunemann, Danielle 01 January 2019 (has links)
Melanoma differentiation associated gene 7/Interleukin-24 (MDA-7/IL-24) is a secreted cytokine which acts as a tumor suppressor. It is capable of selectively killing cancer cells, regardless of anatomic origin, while sparing normal cells. miRNAs are master regulators of gene expression that can play two roles in cancer: tumor-suppression and oncogenesis. We identified a number of miRNAs that are regulated by MDA-7/IL-24 using a PCR plate array containing probes for miRNAs known to play a role in prostate cancer. We independently validated the array with qRT-PCR to identify three miRNAs which are downregulated by MDA-7/IL-24 treatment in DU145, PC3, and PC3ML prostate cancer lines. These miRNAs were miR-125a, miR-145, and miR-23b. Their gene targets were identified using TargetScan and confirmed to be regulated in our prostate cancer model. NLRC5, KLF4, and KLF15, respectively, were upregulated after treatment with MDA-7/IL-24. We focused on NLRC5 as a novel target of MDA-7/IL-24, which plays a role in immune evasion by cancer cells. NLRC5 is upregulated following inhibition of miR-125a. It is not downregulated by overexpression of miR-125a which suggests that more than one miRNA may be acting to regulate its expression. Finally, we determined that miR-125a is downregulated by MDA-7 through DICER, an important processing enzyme for miRNA biogenesis.
680

Random Forests Applied as a Soil Spatial Predictive Model in Arid Utah

Stum, Alexander Knell 01 May 2010 (has links)
Initial soil surveys are incomplete for large tracts of public land in the western USA. Digital soil mapping offers a quantitative approach as an alternative to traditional soil mapping. I sought to predict soil classes across an arid to semiarid watershed of western Utah by applying random forests (RF) and using environmental covariates derived from Landsat 7 Enhanced Thematic Mapper Plus (ETM+) and digital elevation models (DEM). Random forests are similar to classification and regression trees (CART). However, RF is doubly random. Many (e.g., 500) weak trees are grown (trained) independently because each tree is trained with a new randomly selected bootstrap sample, and a random subset of variables is used to split each node. To train and validate the RF trees, 561 soil descriptions were made in the field. An additional 111 points were added by case-based reasoning using aerial photo interpretation. As RF makes classification decisions from the mode of many independently grown trees, model uncertainty can be derived. The overall out of the bag (OOB) error was lower without weighting of classes; weighting increased the overall OOB error and the resulting output did not reflect soil-landscape relationships observed in the field. The final RF model had an OOB error of 55.2% and predicted soils on landforms consistent with soil-landscape relationships. The OOB error for individual classes typically decreased with increasing class size. In addition to the final classification, I determined the second and third most likely classification, model confidence, and the hypothetical extent of individual classes. Pixels that had high possibility of belonging to multiple soil classes were aggregated using a minimum confidence value based on limiting soil features, which is an effective and objective method of determining membership in soil map unit associations and complexes mapped at the 1:24,000 scale. Variables derived from both DEM and Landsat 7 ETM+ sources were important for predicting soil classes based on Gini and standard measures of variable importance and OOB errors from groves grown with exclusively DEM- or Landsat-derived data. Random forests was a powerful predictor of soil classes and produced outputs that facilitated further understanding of soil-landscape relationships.

Page generated in 0.0391 seconds