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Correlations Between Changes In The Amount Ofendogenous Phytohormones And Flowering In Thesafflower ( Carthamus Tinctoriusl.), Hasan Baydar, Salih Ülger Jan 1998

Correlations Between Changes In The Amount Ofendogenous Phytohormones And Flowering In Thesafflower ( Carthamus Tinctoriusl.), Hasan Baydar, Salih Ülger

Turkish Journal of Biology

Changes in the amounts of endogenous gibberellic acid (GA 3 ), indole-3-acedic acid (IAA) and abscisic acid (ABA) during different growth periods of the safflower were studied by high-perfor-mance liquid chromatography (HPLC). A correlation was confirmed between low levels of GA 3 , as well as high levels of ABA, and the initia-tion of flowering. IAA reached its maximum level during bud formation, indicating that IAA might play an active role in the differentiation of bud formation. Changes in the amount of endogenous phytohormones in flower buds located in different parts of the plant indicate that ABA in particular plays …


A Study On The Phytoplankton Of Hasan Uğurludam Lake (Samsun-Turkey), Arif Gönülol, Olcay Obali Jan 1998

A Study On The Phytoplankton Of Hasan Uğurludam Lake (Samsun-Turkey), Arif Gönülol, Olcay Obali

Turkish Journal of Biology

The composition and seasonal variations of phytoplankton of Hasan UGURLU Dam Lake were studied using samples collected from two stations between July 1992 to December 1993. 57 taxa were identified belonging to the Bacillariophyta, Chlorophyta, Cyanophyta, Dinophyta and Euglenophyta divisions of phytoplankton. In the phytoplankton, Asterionella formosa, Cyclotella planc-tonica, Pediastrum simplex and Ceratium hirundinella caused water blooms in certain months. The light density and temperature affected the composition and seasonal variations in phytoplankton considerably. Nutrient levels in the lake did not limit the seasonal variations in phytoplankton. It was determined that Lake Hasan Ugurlu had mesotrophic characteristics because of the …


Contribution To The Geographic Distribution Ofrodent Species And Ecological Analyses Of Theirhabitats In Asiatic Turkey, Nuri Yi̇ği̇t, Ercüment Çolak Jan 1998

Contribution To The Geographic Distribution Ofrodent Species And Ecological Analyses Of Theirhabitats In Asiatic Turkey, Nuri Yi̇ği̇t, Ercüment Çolak

Turkish Journal of Biology

Rodent species in 17 selected localities were determined, and these localities were then compared with respect to rodent species composition. It was determined that a total of 27 rodent species are found in these localities, the number in each locality ranging from 6 to 12. Species previ-ously recorded in mixed and decidous forests in northern Asiatic Turkey, such as Glis glis, Muscardinus avellanarius, Microtus subterraneus and Clethrionomys glareolus, were found not to range across forested localities in west and south Asiatic Turkey in the dry summer season. It was also determined that rodents, which live in similar habitats in different …


Decolorization Of Orange Ii Dye With The Crudeculture Filtrate Of White Rot Fungus, Coriolusversi-Color, Özfer Yeşi̇lada, Birgül Özcan Jan 1998

Decolorization Of Orange Ii Dye With The Crudeculture Filtrate Of White Rot Fungus, Coriolusversi-Color, Özfer Yeşi̇lada, Birgül Özcan

Turkish Journal of Biology

Decolorization of Orange II dye was demonstrated with crude culture filtrate of white rot fungus, Coriolus versicolor. It was determined that the rate and extent of decolorization were depend-ent on the age (growth phase) of the crude culture filtrate (CCF). Dye decolorization abilities of the CCF of Funalia trogii, Pleurotus sajor-caju and Phanerochaete chrysosporium ME446, after incubation for 12 days, were also studied. Phanerochaete chrysosporium ME446 was observed to be unable to decolorize any of 4 dyes used. Cyanide and azide, which are known inhibitors of enzyme, inhibited dye decolorization ability of the CCF. Heat treatment terminated decolorization activity of …


Biodegradation Of Heptachlor By Phanerochaetechrysosporium Me 446: The Toxic Effects Ofheptachlor And Its Metabolites On Mice, Münevver Arisoy, Nazif Kolankaya Jan 1998

Biodegradation Of Heptachlor By Phanerochaetechrysosporium Me 446: The Toxic Effects Ofheptachlor And Its Metabolites On Mice, Münevver Arisoy, Nazif Kolankaya

Turkish Journal of Biology

On the basis of degradation properties of Phanerochaete chroysosporiumME 446 found in white-rot fungi in respect of many organic compounds with toxic, mutagenic and carcinogenic charac-teristics, the physiological conditions effective for the degradation of heptachlor (1, 4, 5, 6, 7, 8, 8- heptachloro-3a, 4, 7, 7a-tetrahydro-4, 7-methanoindene), an organic chlorine used in insecticides Phanerochaete chrysosporium ME were determined. The potential toxic effects of heptachlor and metabolites on mice were also investigated. For the degradation of heptachlor, the optimum pH was found to be 5, incubation period 20 days, and incubation temperature, 30 o C-35 o C, while the optimum concentrations …


Tumor Necrosis Factor-\Alpha And Interleukin-6 Inperitoneal Adhesion Formation, Mahmut Başoğlu, Ahmet Kiziltunç, Fatih Akçay, Sait Keleş, Cemal Gündoğdu, Durkaya Ören Jan 1998

Tumor Necrosis Factor-\Alpha And Interleukin-6 Inperitoneal Adhesion Formation, Mahmut Başoğlu, Ahmet Kiziltunç, Fatih Akçay, Sait Keleş, Cemal Gündoğdu, Durkaya Ören

Turkish Journal of Medical Sciences

This study was carried out to assess the role of tumor necrosis factor (TNF-\alpha) and interleukin-6 (IL-6 ) in plasma and peritoneal fluid in higher rates of adhesion formation following standard bowel injury. Forty-five albino rabbits were divided into three equal groups. Blood was obtained from all the rabbits preoperatively. All the rabbits were subjected to a laparotomy. In group 1(control group), the peritoneal cavity was irrigated with normal saline. In group 2 the cecal serosa was abraded, while the rabbits in group 3 had a resection in small bowel of 2 cm. A peritoneal catheter was placed in all …


Glycoprotein Iib/Iiia Inhibitors In Acute Coronarysyndromes: A New Paradigm In Cardiology, Mehmet Ağirbaşli, David M. Kerins Jan 1998

Glycoprotein Iib/Iiia Inhibitors In Acute Coronarysyndromes: A New Paradigm In Cardiology, Mehmet Ağirbaşli, David M. Kerins

Turkish Journal of Medical Sciences

No abstract provided.


Sex Pheromones Of The Cereal Pest Eurygaster Inte-Gricepsputon (Heteroptera: Scutelleridae)- Atheoretical Study, Lemi Türker Jan 1998

Sex Pheromones Of The Cereal Pest Eurygaster Inte-Gricepsputon (Heteroptera: Scutelleridae)- Atheoretical Study, Lemi Türker

Turkish Journal of Biology

AM1-type molecular orbital calculations were performed on the geometry-optimized struc-tures of various 4-(1', 5' - dimethly -4' - heptenylidene) -1- methylcyclohexene isomers. It was found that the major component (4Z, 4'E isomer) of the sex pheromone of Eurygoaster integriceps is very dissimilar in chemical composition to the other isomers, although the stabilities and heats of the for-mation characteristics are comparable. However, some small molecules resembling only a part of the pheromone might exhibit some partial activity.


Sister Chromatid Exchange In Cultured Humanlymphocytes Treated With Carbosulfan, Ethlycarbamate And Ethly Methanesulfonat Separatelyand In Mixtures, Eyyüp Rencüzogullari, Mehmet Topaktas Jan 1998

Sister Chromatid Exchange In Cultured Humanlymphocytes Treated With Carbosulfan, Ethlycarbamate And Ethly Methanesulfonat Separatelyand In Mixtures, Eyyüp Rencüzogullari, Mehmet Topaktas

Turkish Journal of Biology

The aim of this study was to investigate the ability of Carbosulfan (the effective ingredient in Marshal, a carbamate insecticide/nematocide), Ethyl Carbamate (EC=carcinogen and Ethyl Methanesulfonat (EMS=mutagen) separately and in mixtures to induce sister chromatid exchange (SCE) in human lymphocytes and to nivestigate whether the test substances, as a mixture had any syn-ergistic or antogonistic effect. Carbosulfan separately weakly induced SCE during the 48 hour treat-ment. Although EC separately could not induce SCE, EMS separately induced dose-dependently SCE at 24 and 48 hour treatments. EC increased the RI, while Carbosulfan and EMS decreased it during the 48 hour treatment. The …


The Effects Of Vitamin E On Catalase Activies In Various Rat Tissues, Gülinnaz Alper, Mehtap Çinar, Cenk Can, Gülriz Menteş, Biltan Ersöz, Akgün Evinç Jan 1998

The Effects Of Vitamin E On Catalase Activies In Various Rat Tissues, Gülinnaz Alper, Mehtap Çinar, Cenk Can, Gülriz Menteş, Biltan Ersöz, Akgün Evinç

Turkish Journal of Medical Sciences

Vitamin E and other antioxidants prevent or minimize oxidative damage in biological systems. The level of antioxidant defense sufficient to protect the organism from high free radical concentrations is one of the new horizons for Vitamin E research. The role of Vitamin E as a protective agent aganist oxidative stress was evaluated by meas-uring the antioxidant enzyme catalase (CAT) activities in different tissues of Swiss male albino rats aged two months. In this study, rats were divided to three groups; control (n=10), E 1 (n=5) which received 25 mg/kg. per day of Vitamin E, IM. for 10 days and E …


The Pollen Collection Activity And Preference Of Honey Bees (Apis Mellifera) In The Natural Habitat Of Antalya And Some Morphological And Quality Properties Of Different Pollen Types, Hasan Baydar Jan 1998

The Pollen Collection Activity And Preference Of Honey Bees (Apis Mellifera) In The Natural Habitat Of Antalya And Some Morphological And Quality Properties Of Different Pollen Types, Hasan Baydar

Turkish Journal of Agriculture and Forestry

No abstract provided.


Cover And Contents Jan 1998

Cover And Contents

Turkish Journal of Earth Sciences

No abstract provided.


In Vitro Multiplication Of Salep Orchids, Growing Commonly In The Eastmediterranean Region Of Turkey By Embriyo Culture, Kadriye Çağlayan, Ayşe Özavci, Akif Eskalen Jan 1998

In Vitro Multiplication Of Salep Orchids, Growing Commonly In The Eastmediterranean Region Of Turkey By Embriyo Culture, Kadriye Çağlayan, Ayşe Özavci, Akif Eskalen

Turkish Journal of Agriculture and Forestry

Possiblities of in vitro multiplication of salep orchids, which have a great danger of extinction from nature, was investigated. Orchis anatolica Boiss, Orhcis coriophora L., Ophyrs bornumuelleri Schulz, Ophyrs phrigra Fleischm. et Borm., Serapias vomeracea and Himantoglossum affine, which are growing commonly in the East Mediterranean Area, were cultured in vitro by using embryo culture. In order to culture salep embryos, 14 different media were used. The highest average germination rate and plant formation from protocorm were found as 2.39% and 1.86%, respectively on Van Waes Debergh + Tomato Ekstract + Active Carbon (VW&D + TE + AC) media. The …


Cover And Contents Jan 1998

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.


Cover And Contents Jan 1998

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.


Issues Related To Marketing And Extension For Sustainable Agricultural Production In Turkey, Sedef Akgüngör, Taner Kumuk Jan 1998

Issues Related To Marketing And Extension For Sustainable Agricultural Production In Turkey, Sedef Akgüngör, Taner Kumuk

Turkish Journal of Agriculture and Forestry

Sustainable agriculture, although a difficult term to define operationally, includes the practice of low input agricultural production technologies. An important condition to adopt these technologies is the access to markets for low input agricultural products. Ability to market these products at profitable prices would provide incentives for farmers to adopt the necessary methods. Contract farming is considered to be an effective means to introduce new production technologies to the farmers by providing assurance on prices and markets for agricultural products. Public extension agencies in developing countries may therefore be concerned to direct their efforts to introduce contract farming models to …


Response Of Apis Mellifera Syriacaand A. M. Armeniacatonectar Variations: Implications For Agriculture, İbrahim Çakmak, Harrington Wells, Çetin Firatli Jan 1998

Response Of Apis Mellifera Syriacaand A. M. Armeniacatonectar Variations: Implications For Agriculture, İbrahim Çakmak, Harrington Wells, Çetin Firatli

Turkish Journal of Agriculture and Forestry

The foraging ecology of Apis mellifera syriaca and A. m. armeniaca was studied using artificial flower patches consisting of blue, white, and yellow flowers. Two experiments were performed with each race. Experiment I examined forager response to differences in sucrose reward molarity (quality of reward) associated with flower colors. Experiment II varied the quantity of sucrose reward associated with flower colors. A. m. syriacaand A. m. armeniacaeach responded to quality and quantity differences between blue and white flowers. Prior studies show that A. m. caucasica and A. m. ligustica respond to reward quality difference, but they do not respond to …


Assessment Of Response To Drought Stress Of Chickpea(Cicer Arietinuml.) Lines Under Rainfed Conditions, Cengiz Toker, M. İlhan Çağirgan Jan 1998

Assessment Of Response To Drought Stress Of Chickpea(Cicer Arietinuml.) Lines Under Rainfed Conditions, Cengiz Toker, M. İlhan Çağirgan

Turkish Journal of Agriculture and Forestry

Totally sixty four chickpea lines were grown for assesment of response to drought stress in the stress and non-stress environments under rainfed conditions. The seed yield of the lines when grown under the non-stress condition increased at a rate of 53% over the in stress condition. The line, FLIP 92-154C, was determinated as the best tolerant line to drought stress environment under the field condition. Also, seed yield strongly correlated with biological yield, harvest index, mean productivity, tolerance to drought stress and drought susceptibility index in the stress environment.


Cover And Contents Jan 1998

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.


Heme Transfer Reactions: An Important Prerequisite For Synthetic Oxygen Carriers, Jan Paul, Wenhua Chen, Per-Ingvar Ohlsson, Michael Smith Jan 1998

Heme Transfer Reactions: An Important Prerequisite For Synthetic Oxygen Carriers, Jan Paul, Wenhua Chen, Per-Ingvar Ohlsson, Michael Smith

Turkish Journal of Chemistry

Electronic changes of iron- and metal free porphyrins are reviewed in light of their importance to modify the ferri/ferro reduction potential and energy dissipation between ligated carbon monoxide and the porphyrin chelate. Substitutions at positions 2 and 4 are effective ways to exercise this influence. Other measures include exposure to water and modifications of axial ligation, including the \lq three-ligand' case. These measures will also influence the stability of recombined hemin-protein entities, as apparent from the kinetics of heme-transfer from a modified donor protein to apomyoglobin, but the stability appears to be related to the bulkiness of 2,4-substitutional groups rather …


Cover And Contents Jan 1998

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.


Reactions Of 4-Amino-4,5-Dihydro-1h-1,2,4-Triazol-5-Ones And 4-Amino-4h-1,2,4-Triazoles With Some Carboxylic Acid Anhydrides, Şule Bahçeci̇, Nurhan İnce, Asun İki̇zler Jan 1998

Reactions Of 4-Amino-4,5-Dihydro-1h-1,2,4-Triazol-5-Ones And 4-Amino-4h-1,2,4-Triazoles With Some Carboxylic Acid Anhydrides, Şule Bahçeci̇, Nurhan İnce, Asun İki̇zler

Turkish Journal of Chemistry

3-Alkyl(Aryl)-4-tetrachlorophthalimido-4,5-dihydro-1H-1,2,4-triazol-5-ones (2) and 3-alkyl(aryl)-4-(1,8-naphthalimido)-4,5-dihydro-1H-1,2,4-triazol-5-ones (3) were synthesized from the reactions of 3-alkyl(aryl)-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones (1) with tetrachlorophthalic anhydride and 1,8-naphthalic anhydride, respectively. In addition, the reactions of 4-amino-4H-1,2,4-triazoles (4) with succinic anhydride and phthalic anhydride were studied.


Determination Of Structure-Toxicity Relationship Of Amphiprotic Compounds By Means Of The Inhibition Of The Dehydrogenase Activity Of Pseudomonas Putida, Ş. Gül, D. Öztürk Jan 1998

Determination Of Structure-Toxicity Relationship Of Amphiprotic Compounds By Means Of The Inhibition Of The Dehydrogenase Activity Of Pseudomonas Putida, Ş. Gül, D. Öztürk

Turkish Journal of Chemistry

Aliphatic and aromatic alcohols are amphiprotic compounds which have both polar and nonpolar parts in their structure. These compounds were studied with respect to the nonreactive toxic effects on the microorganism {\it Pseudomonas putida}. The toxicity of these chemicals to aerobic bacterium {\it P. putida} was measured in terms of inhibition of dehydrogenase activity. The test results, expressed as concentration of chemicals 50\% effective in inhibition (IC$_{50}$), were correlated with their physicochemical properties such as aqueous solubility (S) and octanol-water partition coefficient (P).


Comparison Of Different Production Processes For Bioethanol, B. Çaylak, Fazilet Vardar Sukan Jan 1998

Comparison Of Different Production Processes For Bioethanol, B. Çaylak, Fazilet Vardar Sukan

Turkish Journal of Chemistry

In this study, ethanol was produced with the microorganism {\em Saccharomyces cerevisiae} by using sucrose as a substrate. Batch processes were tested by using the same substrate, microorganism and medium composition. {\em Saccharomyces cerevisiae}, used in the free form in the first group of experiments, was immobilized by different methods. In the second group of experiments agar, sponge and a natural material called luffa cylindrica fiber were used as support materials. The batch processes with free and immobilized microorganisms were compared with respect to efficiency and yield.


Kinetic Studies Of The Thermal Decomposition Of Di- And Tri-Organotin Derivatives Of 1-Nitroso-2-Naphthol, Saqib Ali, Moazzam H. Bhatti, Sohail Mahmood, Muhammad Mazhar, M. Saleem Khalid, Nazar Hussain Jan 1998

Kinetic Studies Of The Thermal Decomposition Of Di- And Tri-Organotin Derivatives Of 1-Nitroso-2-Naphthol, Saqib Ali, Moazzam H. Bhatti, Sohail Mahmood, Muhammad Mazhar, M. Saleem Khalid, Nazar Hussain

Turkish Journal of Chemistry

The di- and tri-organotin complexes of general formula R$_2$SnL$_2$ and R$_3$SnL where R = C$_4$H$_9$, C$_6$H$_5$, C$_6$H$_5$CH$_2$, C$_6$H$_{11}$ and L=1-nitroso-2-naphthol, were subjected to thermal decomposition by means of thermogravimetry (TG). The decomposition occurred in steps and the kinetics of every set of reactions were determined using the method described by Coats and Redfern. These results were analysed to establish the decomposition kinetics and hence to calculate activation energies. The activation energies were also determined by applying the method described by Horowitz, which yielded comparable results.


Cover And Contents Jan 1998

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.


Phanerochaete Chrysosporium And Funalia Trogii For The Degradation Ofcotton Stalk And Their Laccase, Peroxidase, Ligninase And Cellulaseenzyme Aktivities Under Semi-Solid State Conditions, Sibel Şik, Ali Ünyayar Jan 1998

Phanerochaete Chrysosporium And Funalia Trogii For The Degradation Ofcotton Stalk And Their Laccase, Peroxidase, Ligninase And Cellulaseenzyme Aktivities Under Semi-Solid State Conditions, Sibel Şik, Ali Ünyayar

Turkish Journal of Biology

The potential of white rot fungi, namely Phanerochaete chrysosporium ME 446 and Funalia trogii for the degradation of lignocellulosics and their ligninolytic enzyme activities under semi-solid state conditions has been studied. In this study, cotton plant stalk which is an agrowaste, is used as lignocellulosics material. It's very good source of fibrous raw material for the manufacture of pulp and paper industry, and also is available abundantly. In this study, proportion of lignin and cellulose is in cotton stalk 23±2 % and 40±3 % respectively. Degradation of lignin and cellulose by P. chrysosporium and F. trogii under semi-solid state were …


Combined Effects Of Endosulfan, Dimethoate And Carbaryl On Serumcalcium Levels And Heart Muscle Of Rats, Güldeniz Özmen, E. Arzu Elcüman Jan 1998

Combined Effects Of Endosulfan, Dimethoate And Carbaryl On Serumcalcium Levels And Heart Muscle Of Rats, Güldeniz Özmen, E. Arzu Elcüman

Turkish Journal of Biology

In this study, combination of low [acceptable daily intake (ADI)] and high (10xADI) doses of endosulfan, dimethoate and carbarly were administrated orally to the male rats for 3.5 months. Serum calcium levels of rats in all groups were determined. At the same time, whether or not there was calcification in heart muscle of rats in all groups were investigated histochemically. Serum calcium levels of rats treated with high dose of endosulfan+carbaryl and dimethoate+carbaryl mixture decreased significantly in comparison with controls. Calcification was not found in heart muscle tissues of the rats in all groups according to the results of histochemical …


Fatty Acid Composition In Phospholipid And Triacylglycerol Fractions Ofmelanogryllus Desertuspall. (Orthoptera: Gryllidae), Mehmet Başhan Jan 1998

Fatty Acid Composition In Phospholipid And Triacylglycerol Fractions Ofmelanogryllus Desertuspall. (Orthoptera: Gryllidae), Mehmet Başhan

Turkish Journal of Biology

In this study, the fatty acid compositions in phospholipid and triacylglycerol factions of ten-day- old adults of both sexes of Melanogryllus desertusreared on stock culture medium under labora-tory conditions, and the total fatty acid composition of the stock culture medium were analysed sep-arately by gas chromatography. Quantitative analysis of both fractions and the stock culture medium showed that oleic, palmitic and linoleic acids constituted the major part of the fatty acid compositions. The fatty acid compositions of the phospholipid and triaclglycerol fractions were quantitatively different. Moreover, a polyunsaturat-ed fatty acid. linolenic acid and eicosapentaenoic acids which is the precursor of …


Detection Of Crown Gal Agent ( Agrobacterium Tumefaciens) Ingrapevine Propagating Material, Kemal Benli̇oğlu, Meriç Özakman Jan 1998

Detection Of Crown Gal Agent ( Agrobacterium Tumefaciens) Ingrapevine Propagating Material, Kemal Benli̇oğlu, Meriç Özakman

Turkish Journal of Agriculture and Forestry

Polyclonal antiserum produced against Agrobacterium tumefaciens (biovar 3) reacted in immunofluorescent test with biovar 3 strains of A.tumefaciens,causal agent of crown gal, from Central Anatolia. The antiserum did not react with A.tumefaciens biovar 1 (except for 1/200 dilution), biovar 2, other plant pathogens and symbionts. Vacuum extraction procedure were applied to recover A.tumefaciens from xylem vessels of one year old dormant grape cuttings. IFAS and selective media were used to detect bacteria. A.tumefaciens (biovar 3) was recovered from six cuttings of 8 infected vines and seven of 150 apparently healthy vines in Central Anatolia. The sensitivity thershold of the vacuum …