Effects of thermal annealing on the morphology of the AlxGa(1x)N films

Cataloged from PDF version of article.Effects of thermal annealing on the morphology of the AlxGa(1-x)N films with two different high Al-contents (x=0.43 and 0.52) have been investigated by atomic force microscopy (AFM). The annealing treatments were performed in a nitrogen (N-2) gas ambient as short-time (4 min) and long-time (30 min). Firstly, the films were annealed as short-time in the range of 800-950 degrees C in steps of 50-100 degrees C. The surface root-mean-square (rms) roughness of the films reduced with increasing temperature at short-time annealing (up to 900 degrees C), while their surface morphologies were not changed. At the same time, the degradation appeared on the surface of the film with lower Al-content after 950 degrees C. Secondly, the Al0.43Ga0.57N film was annealed as long-time in the range of 1000-1200 degrees C in steps of 50 degrees C. The surface morphology and rms roughness of the film with increasing temperature up to 1150 degrees C did not significantly change. Above those temperatures, the surface morphology changed from step-flow to grain-like and the rms roughness significantly increased. (C) 2009 Elsevier Ltd. All rights reserved

Antioxidant capacity and fatty acid profile of <i>Centaurea kotschyi</i> (Boiss. & Heldr.) Hayek var. <i>persica</i> (Boiss.) Wagenitz from Turkey

The antioxidant capacity of the methanolic extract and the fatty acid composition of <i>C. kotschyi</i> var. <i>persica</i> were investigated. Six different chemical methods were used to determine the antioxidant capacity. The fatty acid composition was analyzed using gas chromatography. The IC50 value of the extract was determined as 37.09 μg/ml (in the DPPH assay). In the β-carotene/linoleic acid system, the extract exhibited 65.22% inhibition against linoleic acid oxidation. The amount of total phenolic content and total antioxidant capacity were detected as 36.52 mg gallic acid equivalent (GAE)/g and 74.93 mg ascorbic acid equivalent (AE)/g, respectively. The major fatty acid in the composition of <i>C. kotschyi</i> var. <i>persica</i> was found to be C 18:3 ω3 (α-linolenic acid) by GC analysis. The results presented here indicate that <i>C. kotschyi</i> var. <i>persica</i> possess strong antioxidant properties. Therefore, the species can be used as a natural additive in food, cosmetic and pharmaceutical industries.<br><br>La capacidad antioxidante de extractos metanólicos y composición de ácidos grasos de <i>C. kotschyi</i> var. <i>pérsica</i> fueron investigados. Seis métodos químicos diferentes fueron realizados para la determinación de la capacidad antioxidante. La composición de ácidos grasos fue analizada por cromatografía de gases. Los valores de IC50 de los extractos fueron 37.09 μg/ml (en el ensayo con DPPH). En el sistema β-carotene/ácido linoleico, el extracto mostró un 65.22% de inhibición frente a la oxidación del ácido linoleico. La cantidad total de contenido fenólico y capacidad antioxidante total fueron 36.52 mg equivalentes de ácido gallico (GAE)/g y 74.93 mg equivalentes de ácido ascórbico (AE)/g, respectivamente. El principal ácidos graso encontrado, por análisis de CG, en <i>C. kotschyi</i> var. <i>pérsica</i> fue el C 18:3 ω3 (ácido α-linolenico). Los resultados presentados aquí indican que <i>C. kotschyi</i> var. <i>pérsica</i> posee unas fuertes propiedades antioxidantes. Además, las especies pueden ser usadas como aditivos naturales en los alimentos, en cosmética y en industria farmacéutica

Plot by plot: plotting urbanism as an ordinary process of urbanization

With this paper, we analyse an ordinary urban process, which has received little attention so far and propose a new concept to take account of it: plotting urbanism. It is usually subsumed under terms like “urban informality” or “incremental urbanism” and not studied as a distinct process. In comparing Lagos, Istanbul and Shenzhen we captured four defining features of plotting urbanism: first, it unfolds in a piecemeal fashion with limited comprehensive planning. Second, it emerges from conflicts between multiple overlapping modes of territorial regulation, land tenure and property rights, which result in specific territorial compromises. Third, plotting is based on commodification of housing and land, which might accentuate socio-economic differentiations between property-owners, who often live in the same area, and their tenants. The term “plotting” highlights the key role of the plot in the process. It also alludes to strategic acts of collaboration for individual and collaborative benefit

Branch Retinal Vein Occlusion: Pathogenesis, Visual Prognosis, and Treatment Modalities

In branch retinal vein occlusion (BRVO), abnormal arteriovenous crossing with vein compression, degenerative changes of the vessel wall and abnormal hematological factors constitute the primary mechanism of vessel occlusion. In general, BRVO has a good prognosis: 50–60% of eyes are reported to have a final visual acuity (VA) of 20/40 or better even without treatment. One important prognostic factor for final VA appears to be the initial VA. Grid laser photocoagulation is an established treatment for macular edema in a particular group of patients with BRVO, while promising results for this condition are shown by intravitreal application of steroids or new vascular endothelial growth factor inhibitors. Vitrectomy with or without arteriovenous sheathotomy combined with removal of the internal limiting membrane may improve vision in eyes with macular edema which are unresponsive to or ineligible for laser treatment

Endemic plants and wild Allium species in Turkey

7th International Symposium on Edible Alliaceae -- MAY 21-25, 2015 -- Nigde, TURKEYWOS: 000392629000046The beginning of agricultural plant domestication dates back to as early as humanity. There have been many reports on the total number of plant species, each with varying numbers depending on the specific classification they used. The total number of plants is estimated to be about 400,000 species. Turkey has a broad biodiversity due to numerous microclimates because of its geomorphological structure causing diverse ecology. About 12,000 species are known to exist in Turkey including about 4,000 endemic species, both more than that of European countries. Regarding Nigde and its neighboring provinces, endemic species are reported to be 726 in Konya, 543 in Kayseri, 507 in Nigde, and 100 in Nevsehir. Some of these endemic species are classified as critically endangered (CR). Most of the endemic plants with narrow occurrence in steppe ecosystems fall into CR group. Turkey has numerous endemic plants, but some of them are endangered. About 600 endemic species in Turkey are classified in the CR group and about 700 in the group of Endangered (EN). As in some other countries, numerous endemic plant species were collected between 1992 and 1997, and conserved at the Gene Bank of Menemen, Turkey. The In-situ Conservation of Plant Genetic Diversity National Plan was implemented to employ in-situ conservation of the species that are imperative for agriculture, food, economy and culture. Endemic plant species should be conserved to have them in the future generation not only in Turkey, but also in other countries on the Globe. Therefore, multinational genetic resources programs are still needed, especially for conserving wild plant species. Wild plant species are used by varying communities on the Globe. Plant breeders all over the world use wild types or relatives as germplasm for economically important traits to improve the cultivated species. Allium is one of the most significant types of plants used in the manufacture of curatives in Asia Minor. Because of their flavor, aroma and taste, Allium species are used in food as seasonings, and in folk remedy.Int Soc Hort Sc