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Soil microbial biomass C and N changes in relation to forest conversion in the northwestern Turkey

Kara Ö. | Bolat I.

Article | 2008 | Land Degradation and Development19 ( 4 ) , pp.421 - 428

Tree species differ in their effect on soil development and nutrient cycling. Conversion of beech coppice to pine plantations can alter soil physical and chemical properties, which in turn may have significant impacts on soil microbial biomass C and N (Cmic, Nmic). The major objective of this study was to evaluate soil quality changes associated with the forest conversion in humid NW Turkey. Results from this study showed that levels of soil organic carbon (Corg), total nitrogen (Nt), moisture, Cmic and Nmic, under beech coppice were consistently higher but levels of pH, CaCO3 and EC were lower compared to pine plantation. Differenc . . .es between the forest stands in Cmic and Nmic were mainly related to the size of the Corg stores in soil and to tree species. In addition, high level of CaCO3 is likely to reduce pools of soil organic C and possibly even microbial biomass C and N in pine forests. The average Cmic:Nmic ratios were higher in soils under beech coppice than pine plantation, while Cmic:Corg and Nmic:Nt, percentages were similar in both forest types. These results revealed the differences in microbial community structure associated with different tree species and the complex interrelationships between microbial biomass, soil characteristics, litter quantity and quality. Copyright © 2008 John Wiley & Sons, Ltd Daha fazlası Daha az

Synthesis of water-soluble Mo(0) tetracarbonyl complexes containing nitrogen donor ligands and polymerization of methyl methacrylate

Menteş A. | Hanhan M.E.

Article | 2008 | Transition Metal Chemistry33 ( 1 ) , pp.91 - 97

Water-soluble Mo(0) tetracarbonyl complexes containing a ?-diimine ligand have been prepared. All the complexes were characterized by elemental, LC-MS (APCI), FT-IR, 1H-NMR, and 13C-NMR spectroscopy. The pH dependent phase transfer of these complexes was investigated. This pH dependent phase transfer was accomplished over 10 times with no evidence of complex decomposition. Their catalytic activities on methyl methacrylate polymerization were determined. © 2007 Springer Science+Business Media B.V.

Portföy Seçimi: Uluslararası Hisse Senetleri Portföylerine Uygulaması

Korkmaz, Tuhan | Birkan, Elif

Article | 2008 | İ M K B Dergisi10 ( 40 ) , pp.69 - 104

Bu çalışmada, küreselleşme ve teknolojik ilerlemeler sonucunda ekonomik entegrasyonun artmasına rağmen uluslararası çeşitlendirmede, gelişmekte olan ülkelerin yatırımcılara kayda değer bir çeşitlendirme faydası sunup sunmadığı incelenmiştir. Markowitz Ortalama-Varyans Modeline göre uluslararası alanda çeşitlendirilmiş portföyler oluşturulmuştur. Portföyler gelişmiş ülkelerin, gelişmekte olan ülkelerin ve gelişmiş ülkelerdeki küçük ölçekli firmaların hisse senedi endeks getirilerinden ve bunların karmasından meydana gelmiştir. Çalışmada, gelişmiş ülkelerin hisse senetleri ve ADR, gelişmekte olan ülkelerin hisse senetleri ve ADR ile g . . .elişmiş ülkelerdeki küçük ölçekli firmaların hisse senetleri ve ADR'lerin yer aldığı portföyler de oluşturulmuştur. Markowitz Ortalama-Varyans modeli ile oluşturulan uluslararası portföylerin performans değerlemesi yapılmış ve Riske Maruz Değerleri (RMD) hesaplanarak çeşitlendirmeden elde edilen tasarruflar sayısal olarak ifade edilmiştir. In this study, despite the increasing economic integration because of the globalization and technological improvement, whether emerging markets provides international diversification benefits to investors is examined. International diversified portfolios are created according to Markowitz's Mean-Variance Model. These portfolios consist of equity indices returns of developed markets, emerging markets and SMEs (small-medium enterprises) in developed markets. Also, portfolios consisting of ADR and equity indices returns of developed markets, emerging markets and SMEs are created. International diversified portfolios created with Markowitz's Mean-Variance Model are evaluated according to performance evalution criterions and VaR of these portfolios are calculated so that benefits of diversification are expressed quantitatively Daha fazlası Daha az

Strength functions for transfer of a neutron-proton pair on Se-82, Mo-96, Cd-116 and Te-128 nuclei

Aytekin, H. | Yilmaz, A.

Article | 2008 | PHYSICA SCRIPTA78 ( 4 ) , pp.69 - 104

This study presents the calculation of strength functions for neutron-proton pair transfer on Se-82, Mo-96, Cd-116 and Te-128 even-even nuclei. We study 1(+) states, which are a part of the Gamow-Teller (GT) giant resonances in neighboring odd-odd nuclei, excited via the neutron-proton pair transfer on even-even parent nuclei. The main result of this work is to find these states using strength functions. Calculations have been made only in the particle-particle channel of charge-exchange spin-spin forces via the random phase approximation (RPA).

Expression of histamine receptors (H1, H2, and H3) in the rabbit endolymphatic sac: an immunohistochemical study

Dagli M. | Goksu N. | Eryilmaz A. | Mocan Kuzey G. | Bayazit Y. | Gun B.D. | Gocer C.

Article | 2008 | American Journal of Otolaryngology - Head and Neck Medicine and Surgery29 ( 1 ) , pp.20 - 23

Objective: The endolymphatic sac (ES) is part of the membranous labyrinth of the inner ear. Its central role in immunologic activity within the inner ear has been confirmed by numerous studies. The aim of this study was to investigate the expression of histamine receptors (H1, H2, H3) in the rabbit ES. Methods: A total of 10 healthy male New Zealand white rabbits weighing 2 to 3 kg were used in the experiments. For immunohistochemical studies, immunostaining was performed according to the avidin-biotin-peroxidase complex technique. Results: Serial sections of the ES of rabbits revealed the presence of H1, H2, and H3 receptor immunor . . .eactivity. Immunoreactive cells for all H1, H2, and H3 were found in the epithelial and subepithelial layers of the duct and the proximal ES. In conclusion, this study showed the immunohistochemical localization of H1, H2, and H3 receptors in the ES of rabbits. These receptors may be important in the homeostasis of the inner ear. In addition, they may be target receptors in the medical treatment of inner ear disorders such as endolymphatic hydrops. © 2008 Daha fazlası Daha az

Arazinin yanlış kullanımından kaynaklanan sorunlar: Bartın kenti örneği

Açıksöz, Sebahat | Topay, Mehmet | Yılmaz, Bülent

Article | 2008 | Süleyman Demirel Üniversitesi Orman Fakültesi Dergisi Seri: A0 ( 1 ) , pp.155 - 167

Arazinin yanlıs kullanımından kaynaklanan önemli sorunlardan biri toprak kaybıdır. Bu nedenle Dünya’da ve Türkiye’de büyük miktarda toprak kaybedilmektedir. Çalısmada, yanlıs arazi kullanımından kaynaklanan toprak kaybına iliskin sorunlar belirlenmis ve çözüm önerileri ortaya konulmustur. Bu bağlamda, Bartın Kent Merkezi arastırma alanı olarak seçilmistir. Arastırma alanında toprak özellikleri dikkate alındığında en önemli alan kullanım biçimlerinin tarım, yerlesim ve sanayi olduğu saptanmıstır. Tarım alanlarının %52’sinin IV. sınıf tarım arazisi üzerinde ve %83’ünün orta siddetli erozyon riski tasıyan bölgelerde; yerlesim alanının . . .%49’u ile sanayi bölgesinin %67’sinin ise I. sınıf tarım arazi üzerinde olduğu belirlenmistir. Because of inappropriate land uses, loses of soil is the one of the important problems. Therefore, a huge amount of soil has been lost in all over the world and Turkey. In the study, the problems related with the loses of soil occurring the inappropriate land uses were determined and the suggestions related with the solutions were put forward. In this context, the City of Bartın was selected as a case area. When the soil features took into consideration in there, the most important types of land use were determined as agriculture, settlement and industry. The 52 percent of the whole agriculture lands were located into the Class IV type farming land and the 83 percent of the total agriculture lands were on the region that has middle erosion risk. The 49 percent of settlement area and the 67 percent of industrial areas were on the Class I type farming land were determined Daha fazlası Daha az

Hygienic hand washing among nursing students in Turkey

Çelik S. | Koçaşli S.

Article | 2008 | Applied Nursing Research21 ( 4 ) , pp.207 - 211

The purpose of this study was to determine the application status of hand-washing information given within the context of infection control measures in practice areas among nursing students. This descriptive study was conducted with 430 students. A questionnaire was filled out by the students. In the statistical analysis, frequency, percentage, and ?2 values were measured for all the questions in the hand-washing questionnaire. We determined that students wash their hands before and after each clinical procedure at a rate of 80.2%. Most of the students (71.9%) reported that they wash their hands for 1 minute or longer. The students' . . . answers showed that the nursing education program, including hand-washing applications within the context of infection control measures, is updated but that the students neither practice what they have learned nor give adequate attention to the subject. © 2008 Elsevier Inc. All rights reserved Daha fazlası Daha az

A timelike Cauchy problem and an inverse problem for general hyperbolic equations

Amirov A. | Yamamoto M.

Article | 2008 | Applied Mathematics Letters21 ( 9 ) , pp.885 - 891

We prove a Carleman estimate for hyperbolic equations with variable principal parts and present applications to the unique continuation and an inverse problem. Our Carleman estimate covers cases which the existing Carleman estimates do not treat. © 2007 Elsevier Ltd. All rights reserved.

Evaluation of adjuvant chemotherapy-induced anemia in colon cancer patients (pts)

Engin, H. | Sokmen, F. C. | Akoz, A. G. | Ustunda, Y. | Ankaral, H.

Conference Object | 2008 | JOURNAL OF CLINICAL ONCOLOGY26 ( 15 ) , pp.885 - 891

WOS: 000208457403448

Use of luteal estrogen supplementation in normal responder patients treated with fixed multidose GnRH antagonist: a prospective randomized controlled study

Ceyhan S.T. | Basaran M. | Kemal Duru N. | Yilmaz A. | Göktolga U. | Baser I.

Article | 2008 | Fertility and Sterility89 ( 6 ) , pp.1827 - 1830

To evaluate the effect of luteal estrogen supplementation on pregnancy rates in normal responder IVF patients treated with recombinant FSH and fixed multidose GnRH antagonist, patients were randomized into two groups to receive vaginal 600 mg/d micronized progesterone for luteal phase supplementation with or without transdermal estrogen supplementation (100 µg/d). Because pregnancy rates and ongoing pregnancy rates were similar with and without estrogen supplementation (50.0% vs. 55.2% and 36.6% vs. 34.4%, respectively), we concluded that luteal estrogen supplementation in fixed multidose GnRH antagonist cycles did not change the pr . . .egnancy rates significantly. © 2008 American Society for Reproductive Medicine Daha fazlası Daha az

Flotation of bituminous coal slimes in the Cyclojet cell and a comparison of Cyclojet cell and Jameson cell in terms of their flotation performance [Siklojet hücresinde bitümlü şlam kümü rün flotasyonu ve Jameson hücresi jle flotasyon performanslarinin karşilaştirilmasi]

Hacifazlioglu H. | Toroglu I.

Article | 2008 | Madencilik47 ( 1 ) , pp.3 - 12

This study is aimed at describing in detail the working principle of a Cyclojet cell developed by the Department of Mining Engineering of Zonguldak Karaelmas University, Turkey, and testing it to find out whether it can be used in cleaning bituminous coal slimes. 80% of the bituminous coal slime used in the tests was finer than 53 µrn and it had an ash content of approximately 49%. By using the Cyclojet, the coal slimes yielded clean coal products having 11,32% ash content with 72,80% combustible matter recovery. Tests conducted in the Jameson cell with the same coal slimes produced clean coals having an ash content of 14,40% with 7 . . .3,82% combustible matter recovery. A release test was also applied to the coal slimes in a mechanical cell in order to assess the flotation performance of the Cyclojet cell and compare it with that of Jameson cell. In conclusion, it has been established that the Cyclojet cell produces cleaner products than the Jameson cell with approximately the same flotation yields. The underlying reason is the cyclonic jet action (by centrifugal forces) occurring in the Cyclojet cell and a vortex flow on the cell surface Daha fazlası Daha az

Ligand effects in palladium-catalyzed Suzuki and Heck coupling reactions

Hanhan M.E.

Article | 2008 | Applied Organometallic Chemistry22 ( 5 ) , pp.270 - 275

A range of sterically hindered diimine ligands and their palladium (II) complexes were synthesized. These compounds were fully characterized by elemental analysis, 1H and 13C-NMR spectroscopy. The use of the palladium complexes as catalysts for Suzuki and Heck coupling has been studied in an attempt to demonstrate the effect of side groups on catalytic activity. It was clearly seen that the location of side -CH3 groups which bound to benzene ring had little effect on catalytic activity. Interestingly when we changed these -CH3 groups with -Cl groups the activity of the complexes increased. On the other hand, side groups which bound . . .to imine nitrogen also had a large effect on catalytic activity. Copyright © 2008 John Wiley & Sons, Ltd Daha fazlası Daha az

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