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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.
1

A review of data bearing on the users role in industrial innovation

January 1978 (has links)
Eric von Hippel. / Includes bibliographical references.
2

Comparative Vegetative Anatomy Of The Tribe Triticeae Dumortier (poaceae) In Turkey

Mavi, Dudu Ozlem 01 September 2012 (has links) (PDF)
Triticeae Dumort. is a tribe within the Pooideae subfamily of Poaceae. Major crop genera found in this tribe include barley (Hordeum), wheat (Triticum) and rye (Secale) all of which are closely related to each other. In Turkey, with the several subgroups, this tribe is represented by 16 genera and 75 species, many of which have great economic values. The main objective of this research work is to determine the taxa of this tribe on the basis of their diagnostic anatomical characters of vegetative organs for the recognision of genera, sections, species, and infraspecific categories. By using both fresh and herbarium specimens, transverse sections of vegetative organs were obtained by using two different sectioning methods. This study covers both qualitative anatomical characters, such as sclerenchyma position, hair density and intercellular cavities of roots, shapes of leaves, presence of midrib, occurrence of leaf hairs, shapes of girders or strands, arrangement of sclerenchyma around vascular bundles and arrangement of epidermal cells, cell wall undulations, appearance of silica bodies, type of bulliform cells, arrangement of culm vascular bundles and their connections to the epidermis, hollowness of culms, as well as quantitative characters, such as sclerenchyma line number of roots, vascular bundle line numbers and diameters of culms, sclerenchyma line number of leaf margins, line numbers and sizes of all types of costal leaf hairs, stomata and interstomatal cell lines. In conclusion, all these properties are useful to understand both systematics and evolutionary relationships of the taxa. Moreover, the leaves of the tribe have the most numerous diagnostic characters. The roots do not have central metaxylem. The metaxylem elements are scattered in the vascular cylinder. The internodular parts of the culms may be hollowed or solid. However, the nodular parts of the culms generally have the same structure. Furthermore, there are two species which can be assigned as a subtribe.
3

Adapting And Testing A Community Classification System For Mediterranean Turkey Using Satellite Imagery

Zeydanli, Ugur 01 February 2007 (has links) (PDF)
Throughout the past century, vegetation scientists have been studying plant communities to develop classification standards for global mapping purposes. In Turkey, although there are several vegetation classification schemes in use by botanists, foresters or geographers, none is widely accepted by all for vegetation mapping. In this study, a hierarchical, ecologically meaningful, physiognomic-floristic classification system was adapted and developed for terrestrial vegetation in Turkey. The system has eight hierarchical levels, with the alliance and the association as its lowest two floristic levels, and the classes are designed to be easily detected in the field or indirectly through remote sensing. To test of its utility, a supervised vegetation classification of the whole Mediterranean Region of Turkey was carried out using Landsat ETM images. The accuracy of the classification ranged between 55% and 69% depending on the level of hierarchy. A further test for its ecological utility was carried out by comparing identified vegetation classes with breeding bird communities derived from data gathered through field observations at 193 ecological communities at 83 sites. The proposed classification scheme has proven to be reasonably accurate when widely available satellite imagery is used and ecologically meaningful as shown by a high concordance with observed bird community patterns. It is suggested that this new system can be safely applied to other regions of Turkey for purposes of vegetation mapping, species habitat modeling, and nature conservation if proper image set and ancillary data is used.
4

The Phylogenetic Analysis Of Liquidambar Orientalis Mill. Varieties By Comparing The Non-coding Trn Regions Of The Chloroplast Genome

Or, Melis 01 August 2007 (has links) (PDF)
Liquidambar L. genus are represented with four species in the world and one of these species, Turkish sweet gum (Liquidambar orientalis Miller) is naturally found only in southwestern Turkey with limited distribution in Mugla Province. The presence of increasing threats to its genetic resources signifies the importance of studying the phylogenetic relationships and genetic diversity in this relict endemic species. In this study, 18 different populations were sampled throughout the species range and noncoding transfer ribonucleic acid (trn) region of chloroplast DNA was studied to asses the phylogenetic relationships and genetic diversity. Experimental studies included the extraction of DNA, amplification and sequencing of the trn region of the chloroplast DNA. Molecular evolutionary analysis was done by using MEGA version 3.1 and Arlequin 2.000 softwares. Sequences from six other species of Liquidambar (L. styraciflua from USA, L. macrophylla from Mexico, L. formosana from Vietnam, L. acalycina from China, L. formosana from China and L. acalycina from USA) in the database were also included in the analysis. Moleculer diversity results show that population located in Mugla-Yatagan district has the highest number of polymorphic sites among the other populations of Turkish sweet gum. Population located in Marmaris-G&uuml / nn&uuml / cek has an average genetic distance value of 0.0032 within population, being the highest within the studied populations of Turkish sweet gum. The average genetic distance within variety orientalis (0.0011) was the greatest among all the varieties, but the most separated or divergent populations were members of variety integriloba. For both varieties and geographic groups, average diversity within was found to be the greatest portion (greater than 80%) of the total sequence diversity. The geographic groups located in Denizli and Mugla-Yatagan showed the highest average genetic distances within location, with a value of 0.0014. The genetic distance between the closest neighbor of Turkish sweet gum, American L. styraciflua was 0.0002, whereas the genetic distance between the most distant neighbors (Vietnamese L. formosana, Chinese L. acalycina and L. formosana) was 0.0051. Based on the molecular diversity analysis, seven populations were found to be important for conservation issues and two of them located in Marmaris have the highest priority. The most variant geographic groups are located in Denizli and Mugla-Yatagan districts. These populations could be considered as good candidates for future in-situ or ex-situ conservation programs
5

Population Status, Threats And Conservation Approaches For A Highly Threatened Endemic Plant, Centaurea Tchihatcheffii Fisch. &amp / Mey

Erguner Baytok, Yasemin 01 October 2008 (has links) (PDF)
Centaurea tchihatcheffii Fisch. &amp / Mey. is a critically endangered annual endemic plant found only in Ankara. This study aimed to determine its distributional range, metapopulation status, the effects of agricultural activities, and assess conservation options. Occurrences and population size estimates were carried out by ground surveys. Two adjacent subpopulations were intensively studied during 2004-2008. Plant and seed demographic data were collected in the field and by laboratory tests. Field experiments simulated the effects of agricultural practices. Risks of extinction and possible impacts of different management actions were investigated through a population viability analysis (PVA) by constructing a two-stage stochastic model. Six scenarios involving different management actions were run with 10,000 replications each using RAMAS Metapop. A total of 14 patchily distributed subpopulations were found to have an extent of occurrence of &gt / 700 km2. Herbicide applications caused extreme mortality and reduced germination success, and were shown to be the major anthropogenic threat against long-term survival of C. tchihatcheffii. Tillage led to an increase in density and reproductive success in the following year. PVA simulations for most scenarios predicted extinction of both subpopulations within 4 to 95 years, but a conservation management scenario involving delayed tillage ensured viable populations with a combined size of 21 million individuals. PVA results demonstrated that timing and frequency of tillage is crucial. Therefore, we propose tillage to be carried out after seed set every other year for protected subpopulations to ensure their long term persistence. Alternatively, unprotected subpopulations elsewhere can benefit from organic or nature-friendly farming.
6

Revision Of The Genus Salvia L. (labiatae) In The Mediterranean And The Aegean Geographic Regions Of Turkey

Celep, Ferhat 01 October 2010 (has links) (PDF)
A revision of the Mediterranean and the Aegean geographic regions of Turkey of Salvia L. (Labiatae) is presented. According to the results, the study area has 60 taxa, 32 of which are endemic (mainly local endemics), 5 of which are non-endemic rare, and the remaining 23 taxa are widely distributed. The rate of endemism is 53% in the area. At the beginning of the thesis, history and worldwide distribution of the family and the genus are briefly given. Phylogenetic studies and infrageneric grouping of the genus are discussed. As well as, recent studies on the genus such as taxonomical, morphological, micromorphological and karyological are provided. Geographic, phytogeographic, topographic, and climatic features of the area are explained. Since 2005, about 2000 specimens have been collected and examined as the research materials. In addition, a large number of specimens have been seen and studied in ANK, AEF, BM, E, ERCIYES, G, GAZI, HUB, K, KNYA, LE, ISTE and ISTF herbaria. Digital photos of some specimens including type specimens have been seen from B, W and A herbaria. In the field when the specimens were detected geographical location (including GPS), habitat, phenological data and relevant field observations were all recorded. In the study, comparative morphological characters and their variations are discussed Anatomical features, such as root, stem, leaf and petiole, micromorphological properties, such as trichome, pollen and nutlet, of the species are comprehensively studied and their taxonomic implications are discussed. According to field studies and literature surveys, endemism, pyhtogeography, habitat, phenology, chorology, new distribution areas and conservation status of the species are determined. Infrageneric delimitation of the species using multivariety analysis is performed. In addition, first sectional key and sectional grouping of the species are made. As well as, identification key of the species is given. At the end of the thesis, expanded and corrected description, address, photographs and some notes on taxonomy of the species are given. The taxonomic studies revealed one new species, Salvia marashica, two new varieties, S. sericeo-tomentosa var. hatayica, S. cadmica var. bozkiriensis, one new combination, S. aucheri subsp. canescens and one new record, S. viscosa. As well as, S. sericeo-tomentosa and S. quezelii are rediscovered.
7

The Staminal Lever Mechanism And Floral Diversity Of Some Bee-pollinated Salvia L. (lamiaceae) Species

Atalay, Zeynep 01 July 2011 (has links) (PDF)
The characteristic staminal lever mechanism is defined as a functional unit including the modification of stamens into lever-like structures, their reversible movement and the organisation with the remaining floral structures and they are involved in the process of pollen transfer. The staminal levers play a major role in the process of pollen deposition on the pollinators&rsquo / body and their proportion and interaction with pollinators may have significant consequences for the pollination system in Salvia. In this study, staminal lever mechanism and floral diversity of bee pollinated species including Salvia absconditiflora, Salvia aethiopis, Salvia russellii, Salvia tchihatcheffii which grow sympatrically are investigated in the campus flora of Middle East Technical University. The functioning of the staminal lever mechanism is tested and pollinators of the Salvia species are observed by field investigations. Special attention is given to species-specific patterns of pollen deposition on the pollinators&rsquo / body. Floral diversity of the Salvia species such as corolla shape, size, colour, stamen type are studied. Floral and pollinator structures are measured morphometrically by laboratory investigations. Moreover, the isolation mechanism among the co-occuring Salvia species are investigated by field observations. All field observations are backed by photos and video recordings. Field and laboratory investigations revealed that co-occuring Salvia species are reproductively isolated by several means and the diversity of floral constructions and staminal lever mechanism increases the mechanical isolation by attracting different pollinators and by loading pollen on different parts of their bodies.
8

A Phenetics Study For Infrageneric Grouping Of Limonium Mill. Genus (plumbaginaceae) In Turkey

Fazlioglu, Fatih 01 October 2011 (has links) (PDF)
In this study, current infrageneric taxonomic status of Limonium Mill. in Turkey was assessed by using numerical taxonomy (phenetics) method. Herbarium materials belong to 21 species of Limonium Mill., collected all around Turkey, and were examined. In order to evaluate the infrageneric status, 52 characters based on ecological and morphological features of the genus were determined and recorded to construct a data matrix which was analyzed by MultiVariate Statistical Package (MVSP) and Statistica software with Unweighted Pair Group Method with Arithmetic Mean (UPGMA) method to construct phenograms. Then, by assesing the phenograms, an overall comparison of Limonium Mill. species were made and infrageneric taxonomic status of the genus was discussed. The result of this study indicated that 5 sections of the genus are represented in phenograms which was a compatible result with theoretical information written in 7th Volume of &ldquo / Flora of Turkey&rdquo / . Moreover, in UPGMA trees, a new section (belonging Section Limonium) is observed. Section nova species live only near seashore and distinctively separated from other Section Limonium species in phenograms and Principle Component Analysis (PCA). PCA was carried out to indicate most important characters used in this study. In addition, in this study, a dichotomous key comprising all the species of Limonium Mill. in Turkey was also presented. In appendix part, brief information about each species such as distribution, habitat, conservation status, habit, endemism ratio, flowering period, IUCN categories was given to review all Limonium Mill. species in Turkey.
9

Revision Of Vicia L. (leguminosae) In Central Anatolia, Turkey

Binzat, Okan Kaan 01 October 2012 (has links) (PDF)
In this revisional study based on the the genus Vicia in Central Anatolia large quantities of data have been compilled from specimens representing the group of the taxa being studied. These data were then synthesized to make taxon descriptions, keys, geographical distributions and ecological preferences. Since 2009, about 700 specimens have been collected from Central Anatolia and examined as the research materials. In addition, a large number of specimens have also been studied in the following herbaria ANK, GAZI, MUG, HUB and E. According to the Flora of Turkey (Davis 1985), there were 16 species found in Central Anatolia. But this study has shown that genus Vicia covers 22 species (V. noeana, V. anatolica, V. pannonica, V. hybrida, V. sericocarpa, V. narbonensis, V. galilaea, V. ervilia, V. caesarea, V. cracca, V. villosa, V. monantha, V. canescens, V. cappadocica, V. articulata, V. cassubica, V.peregrina, V. truncatula, V. grandiflora, V. lathyroides, V. cuspidata, V sativa) in this region. v Some morphological characters were used to understand whether they have a diagnostic value or not. These characters, which include habit, leaf, stem, inflorescence, calyx, corolla and style properties, were compared at infrageneric level and species level. Systematic value of pollen micromorphology, trichome micromorphology and petal epidermal micromorphology of Vicia in Central Anatolia were observed. Pollen grains equatorial view, polar view and exine ornamentations, trichome types of calyces and leaves can be useful for separating the species in sectional level. Geographical and ecological distributions maps were updated. In addition to this, the conservation status of the genus Vicia in Cental Anatolia was reassessed at regional level. The threat categories include 2 taxa DD, 1 taxon CR, 7 taxa EN, 1 taxon VU, 1 taxon NT and 14 taxa LC. The main threat categories for this genus are identified as overgrazing, constructions, land clearing and urbanizations. The infrageneric delimitations were performed by the use of multivariate analysis. Identification keys for sections and species were also given. Synonym, species updated descriptions, phenology, habitat, distribution in Central Anatolia, distribution in Turkey and general distribution, phytogeograpy, endemism, specimen citations photographs of species and distribution maps were also indicated.
10

Detection Of Genetically Modified Potatoes By The Polymerase Chain Reaction

Muwonge, Abubaker 01 January 2005 (has links) (PDF)
Quite a number of important crops have been genetically modified with genes for agronomically important traits, such as insect and viral resistance. As the numbers of genetically modified foods continue to increase on the market, the need for rapid development of GMO detection methods is indispensable. This study was carried out to detect if genetically modified potatoes exist on food market in Turkey. Thirty samples from different places were collected. Using a DNA based PCR method, potato samples were examined for the presence of 35S promoter, Nos terminator, neomycin phosphotransferase (nptII) genes, and synthetic cry3A gene which is the general transgene in all approved Newleaf transgenic potato lines. The experimental design of this study was to detect Newleaf insect resistant lines. In 11 samples at least one genetic element was detected. Sample R from Ankara has shown to be belonging to Newleaf insect resistant lines. Since 35S promoter was not detected in samples M3, 14 and F1, it is proposed that they are belonging to Newleaf virus and insect resistant lines (Newleaf plus or Newleaf Y). Although Nos terminator was not detected in samples H2, Z2 and D, cry3A fragments amplified in those samples have been verified that they are from the synthetic cry3A regions of Newleaf lines. The detected synthetic cry3A gene in GM potatoes was amplified by specific primers, which cannot amplify Bacillus thuringiensis tenebrionis natural cry3A gene. In addition, the authenticity of the synthetic cry3A PCR products were confirmed by both sequencing and restriction digestions. Our results showed that genetically modified Newleaf potatoes exist in food market in Turkey. Further studies by accredited laboratories are strongly recommended.

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