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Species Composition And Diversity Of Epipelic Algae In Çatal Lake (Şebinkarahisar-Giresun, Turkey), Bülent Şahi̇n Jan 2004

Species Composition And Diversity Of Epipelic Algae In Çatal Lake (Şebinkarahisar-Giresun, Turkey), Bülent Şahi̇n

Turkish Journal of Biology

The epipelic algae of Çatal Lake were studied between June and October 2002. Fifty-three taxa (39 belonging to Bacillariophyta, 8 to Chlorophyta, 5 to Cyanophyta and 1 to Euglenophyta) were determined. Based on the epipelic algal composition, Çatal Lake can be characterized as eutrophic.


In Vitro Antifungal Activity Of Strains Of Trichoderma Harzianum, Çi̇ğdem Küçük, Meri̇h Kivanç Jan 2004

In Vitro Antifungal Activity Of Strains Of Trichoderma Harzianum, Çi̇ğdem Küçük, Meri̇h Kivanç

Turkish Journal of Biology

Interactions between Trichoderma harzianum strains and some soilborne plant pathogens (Gaeumannomyces graminis var. tritici, Fusarium culmorum and F. moniliforme) were studied on PDA medium. All T. harzianum strains tested produced a metabolite that inhibited growth of plant pathogenic fungi on PDA medium. When grown in liquid cultures containing laminarin, chitin or fungal cell walls as sole carbon sources, 2 strains of T. harzianum produced 1,3-\beta-glucanase and chitinase in the medium. Higher levels of these enzymes were induced by T. harzianum T15.


Effect Of Radiation On The Persistent Length Of A Chain, B. L. Oksengendler, Ni̇gora Turaeva, I. N. Ruban, S. Sh. Rashidova Jan 2004

Effect Of Radiation On The Persistent Length Of A Chain, B. L. Oksengendler, Ni̇gora Turaeva, I. N. Ruban, S. Sh. Rashidova

Turkish Journal of Chemistry

The effect of radiation on the persistent length of a chain in a water solution of polymer is considered in the work. This effect is suggested to be related to the breaking of the hydrogen bonds in hydrate layers around the chain. The kinetic equation of the breakage of the hydrogen bonds is defined and the stationary solution is found with the help of the equation. The expression of average value of the persistent length of the chain at a fixed average number of broken bonds is determined by means of the Poisson distribution. We found that the persistent length …


^{1}H, ^{13}C, ^{119}Sn Nmr, Mass, Mössbauer And Biological Studies Of Tri-,Di- And Chlorodiorganotin(Iv) Carboxylates, Hajra Masood, Saqib Ali, Mohummad Mazhar, Saira Shahzadi, Khadija Shahid Jan 2004

^{1}H, ^{13}C, ^{119}Sn Nmr, Mass, Mössbauer And Biological Studies Of Tri-,Di- And Chlorodiorganotin(Iv) Carboxylates, Hajra Masood, Saqib Ali, Mohummad Mazhar, Saira Shahzadi, Khadija Shahid

Turkish Journal of Chemistry

The reaction of 2-[(2,3-dimethylphenyl)amino]benzoic acid (HL) with tri- and diorganotin(IV) chlorides yielded complexes of the type R_{3}SnL and R_{2}SnL_{2} (R = n-C_{4}H_{9}, C_{6}H_{5}, C_{6}H_{5}CH_{2}, n-C_{8}H_{17}). The compounds R_{2}SnClL were obtained by a redistribution reaction between R_{2}SnL_{2} and R_{2}SnCl_{2}. All the compounds were characterized by CHN analysis, infrared, multinuclear NMR, mass and Mössbauer spectroscopy. The possible mode of carboxylate group bonding in solid as well as in solution is proposed on the basis of infrared, Mössbauer and NMR (^{1}H, ^{13}C, ^{119}Sn) spectroscopy.


Cover And Contents Jan 2004

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.


Direct Dyes Derived From 4,4'-Diaminobenzanilide Synthesis, Characterization And Toxicity Evaluation Of A Disazo Symmetric Direct Dye, Georgeta Maria Simu, Sergiu Adrian Chicu, Nicole Morin, Walter Schmidt, Eugen Şişu Jan 2004

Direct Dyes Derived From 4,4'-Diaminobenzanilide Synthesis, Characterization And Toxicity Evaluation Of A Disazo Symmetric Direct Dye, Georgeta Maria Simu, Sergiu Adrian Chicu, Nicole Morin, Walter Schmidt, Eugen Şişu

Turkish Journal of Chemistry

The synthesis of a new symmetric disazo direct dye containing the non--carcinogenic 4,4'-diaminobenzanilide as the middle component and salicylic acid as the coupling component is presented. The synthesized dye is an analog of the benzidine based dye C. I. Direct Yellow 1 (C. I. 22,250) and was analyzed by thin layer chromatography (TLC), electronic spectra (VIS) and mass spectroscopy (FAB-MS). The coloristic and fastness properties of the synthesized dye were determined and compared with those of C. I. Direct Yellow 1. The toxicities of the dye and of its precursors were evaluated by biological tests, using the process of metamorphosis …


Cover And Contents Jan 2004

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.


Isolation And Characterization Of Aerobic Denitrifiers From Agricultural Soil, Ebru Çelen, Mehmet Aki̇f Kiliç Jan 2004

Isolation And Characterization Of Aerobic Denitrifiers From Agricultural Soil, Ebru Çelen, Mehmet Aki̇f Kiliç

Turkish Journal of Biology

Denitrification is generally considered an anaerobic process. However, in recent years it has been shown that bacteria can also reduce nitrate to nitrite under aerobic conditions. The characterization of biologically available nitrogen forms and their biological cycling mechanisms is important for ecological and agricultural implications. In this study, aerobic nitrate reducers were isolated from greenhouse soil. Using a nitrate reduction assay, it was found that 39 out of 60 isolates can reduce nitrate to nitrite under aerobic conditions. Five of those 39 isolates were selected for further characterization of their aerobic nitrate reduction activity. Four of those 5 isolates were …


Cover And Contents Jan 2004

Cover And Contents

Turkish Journal of Biology

No abstract provided.


Evaluation Of Toxicity Of Tannery Effluent On Plankton Community Structure: A Multispecies Microcosm Study Ii, Yalavarthi Naga Koteswari, Ravichandran Ramanibai Jan 2004

Evaluation Of Toxicity Of Tannery Effluent On Plankton Community Structure: A Multispecies Microcosm Study Ii, Yalavarthi Naga Koteswari, Ravichandran Ramanibai

Turkish Journal of Biology

Laboratory experiments were conducted to evaluate the dose-dependent response of tannery effluents on plankton community structure using polyurethane foam (PF) as artificial substrate. Naturally derived planktonic communities on PF provided colonists for the development of new communities under stress conditions in the laboratory. Predictions of colonization rate, taxonomic richness and relative abundance in a series of microcosms dosed with a gradient of tannery effluent from 20% to 35% concentration were assessed after the initial dosage study (1% to 15%). Changes in taxonomic composition occur at high levels of stress. End points responding at increasing levels of stress are declines in …


Cover And Contents Jan 2004

Cover And Contents

Turkish Journal of Veterinary & Animal Sciences

No abstract provided.


Reproductive Biology In A Native European Catfish, Silurus Glanis L., 1758, Population In Menzelet Reservoir, Ahmet Alp, Cemi̇l Kara, Hakan Murat Büyükçapar Jan 2004

Reproductive Biology In A Native European Catfish, Silurus Glanis L., 1758, Population In Menzelet Reservoir, Ahmet Alp, Cemi̇l Kara, Hakan Murat Büyükçapar

Turkish Journal of Veterinary & Animal Sciences

The reproductive activities of Silurus glanis were investigated over 12 months in Menzelet Reservoir, in the East Mediterranean region of Turkey. Total length of the examined 245 S. glanis varied from 33.4 cm (220 g) to 195.0 cm (48,000 g), and age distribution ranged between 1 and 14. Observations on the seasonal distribution of the maturity stages and variations in the gonadosomatic index (GSI) confirmed that Silurus glanis has a prolonged spawning period extending from the beginning of June to August. The males mature earlier than the females, at a minimum size of 78.82 cm in total length and at …


Introducing A New Approach To Estimating Red Meat Production In Turkey, Fahri̇ Yavuz, Carl R. Zulauf Jan 2004

Introducing A New Approach To Estimating Red Meat Production In Turkey, Fahri̇ Yavuz, Carl R. Zulauf

Turkish Journal of Veterinary & Animal Sciences

A common concern with official estimates of red meat production in Turkey is that they underestimate the level of production. One of the frequently cited reasons is that unregulated slaughter is undercounted. This study uses an estimation method based on the biology of red meat production to examine the potential impact of this undercounting. The production estimates obtained for 1991-1998 using this biological-based method exceed the numbers estimated by official organizations, but fall within the range of estimates obtained from other proposed approaches to estimating red meat production.


Can We Use Vitamin E As An Anti-Tumoral Agent For The Treatment Of Tumors In Fish?, Olcay Hi̇sar Jan 2004

Can We Use Vitamin E As An Anti-Tumoral Agent For The Treatment Of Tumors In Fish?, Olcay Hi̇sar

Turkish Journal of Veterinary & Animal Sciences

No abstract provided.


The Reproductive Biology Of The Tench (Tinca Tinca L., 1758) In Kayaboğazı (Kütahya, Turkey) Dam Lake, Ali̇ Alaş, Kemal Solak Jan 2004

The Reproductive Biology Of The Tench (Tinca Tinca L., 1758) In Kayaboğazı (Kütahya, Turkey) Dam Lake, Ali̇ Alaş, Kemal Solak

Turkish Journal of Veterinary & Animal Sciences

This study was carried out between January 1996 and December 1997 in Kayaboğazı Dam Lake. During this period 424 specimens were examined. The age of females and males ranged from I to VII. The fork length and weight of females and males were 102-277 mm and 15-377.02 g and 125-274 mm and 27-369.02 g, respectively. There was no statistically significant difference between females and males in terms of body length and weight.The sex ratio (male:female) was 0.947:1. Gonadosomatic index values varied from 1.40 to 10.19. The sexual maturity age for males and females was III and IV, respectively. The spawning …


The Effect Of Gnrh Administration On Plasma Progesterone And Reproductive Performance In Ewes, Mehmet Aki̇f Çam, Mehmet Kuran, Erdoğan Selçuk Jan 2004

The Effect Of Gnrh Administration On Plasma Progesterone And Reproductive Performance In Ewes, Mehmet Aki̇f Çam, Mehmet Kuran, Erdoğan Selçuk

Turkish Journal of Veterinary & Animal Sciences

Two experiments were carried out to investigate the effect of GnRH administration at mating and on day 12 post-mating on the reproductive performance of Karayaka and Sakız x Karayaka (F_2) crossbred sheep. In the first experiment, ewes were allocated into a control group (K, n = 27), and groups administered 4 µg GnRH at mating (A, n = 27), on day 12 post-mating (AS, n = 30) and both at mating and on day 12 post-mating (AAS, n = 30). GnRH administration in the A and AS groups increased plasma progesterone concentrations (P < 0.01). The pregnancy rate at first mating in the AS group (86.7%) was higher than those in the ASS (66.7%), A (51.9%) and K (51.9%) groups (P < 0.01). There was no difference between the treatment groups in terms of litter sizes (1.31, 1.21, 1.21 and 1.20 for AS, K, A and ASS, respectively). In the second experiment, ewes were allocated into 2 groups, a control group (K, n = 70) and a group administered 4 µg GnRH on day 12 post-mating (AS, n = 73). The pregnancy rate at first mating was 71.4% and 80.8% (P > 0.05) and litter size was 1.24 and …


Recent Developments In International Biological Nomenclature, Werner Greuter Jan 2004

Recent Developments In International Biological Nomenclature, Werner Greuter

Turkish Journal of Botany

After a period of several decades of general neglect, biological systematics and taxonomy are again surfacing to the awareness of the scientific community and of policy makers. This we owe to the fact that they are the core disciplines of biodiversity research, now perceived to be a priority task in view of the impending threat of loss through extinction of a great number of species, and the wholesale destruction of ecosystems. Yet the renaissance of systematics and taxonomy is hampered by the inadequacy of the traditional rules governing the formation and use of scientific names of organisms. Names are a …


The High Mountain Vegetation Of Turkey - A State Of The Art Report, Including A First Annotated Conspectus Of The Major Syntaxa, Gerald Parolly Jan 2004

The High Mountain Vegetation Of Turkey - A State Of The Art Report, Including A First Annotated Conspectus Of The Major Syntaxa, Gerald Parolly

Turkish Journal of Botany

This contribution spotlights the present research on the (oreal) subalpine to subnival mountain vegetation of Turkey. It concisely compiles our present knowledge, which is very heterogeneous in geographical terms. The situation is comparatively good in NW and W Anatolia and the western half of the Taurus range, from where a first consolidation stage can be reported. By contrast, the E Taurus remains a largely unexplored area. The Pontic chains have hitherto attracted a few local researchers only, and those important pioneering accounts cover less than half of the vegetation types actually present. The results of the last years' field work …


Biology Of The Central Desert Of Oman, Shahina A. Ghazanfar Jan 2004

Biology Of The Central Desert Of Oman, Shahina A. Ghazanfar

Turkish Journal of Botany

A biological survey of the central desert of Oman was done using long distance transects. Vegetation was sparse and consisted of 200+ plant species, 22 species of mammals, 17 species of reptiles and amphibians, and more than 50 species of birds (migratory and resident). Three main vegetation types were identified based on ground substrate and the dominance of species. These were communities with Acacia Willd., Zygophyllum L., and open woodlands of Prosopis cineraria (L.) Druce. Over-grazing and development in the central desert has led to concerns over the conservation of the desert ecosystem in Oman.


Cover And Contents Jan 2004

Cover And Contents

Turkish Journal of Botany

No abstract provided.


Cover And Contents Jan 2004

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.


Cover And Contents Jan 2004

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.


Density Of Centaurea Solstitialis L. And Its Natural Enemies Ceratapion Spp. In Southern Turkey, Si̇bel Uygur Jan 2004

Density Of Centaurea Solstitialis L. And Its Natural Enemies Ceratapion Spp. In Southern Turkey, Si̇bel Uygur

Turkish Journal of Agriculture and Forestry

Centaurea solstitialis L., yellow star thistle, is an annual weed that belongs to the family Asteraceae. In Turkey, this weed can be found in pasture areas, along roadsides, in cultivated areas and in field margins. Yellow star thistle is native to Mediterranean and western Asian countries. Alternative management strategies to chemical control have been and still are being studied; for example, management strategies to control this weed in the USA concentrate on the biological control approach. In addition, chemical control methods in pasture areas are banned in Turkey, which led us to carry out this field study. The average percentage …


Cover And Contents Jan 2004

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.


Soil Respiration In Young And Old Oriental Spruce Stands And In Adjacent Grasslands In Artvin, Turkey, Aydin Tüfekçi̇oğlu, Mehmet Küçük Jan 2004

Soil Respiration In Young And Old Oriental Spruce Stands And In Adjacent Grasslands In Artvin, Turkey, Aydin Tüfekçi̇oğlu, Mehmet Küçük

Turkish Journal of Agriculture and Forestry

Soil respiration is a good indicator of soil quality. In this study, the influence of species type and sampling time on soil respiration in young and old oriental spruce (Picea orientalis (L.) Link.) stands without understory and with a Rhododendron ponticum L. understory and in adjacent grasslands were investigated in Genya Mountain, Artvin, Turkey. Soil respiration was measured approximately monthly from May to October using the soda-lime technique. Mean daily soil respiration across all sites ranged from 0.26 to 2.66 g C m^{-2} d^{-1}. There were significant differences between grasslands and old forest sites, but no significant differences between young …


Synthesis Of Some New Substituted 1,2,4-Triazole And 1,3,4-Thiadiazole And Their Derivatives, Khosrow Zamani, Khalil Faghihi, M. Reza Sangi, Javad Zolgharnein Jan 2003

Synthesis Of Some New Substituted 1,2,4-Triazole And 1,3,4-Thiadiazole And Their Derivatives, Khosrow Zamani, Khalil Faghihi, M. Reza Sangi, Javad Zolgharnein

Turkish Journal of Chemistry

Several 5-(isomeric pyridyl)-4-aryl-1,2,4-triazole-3-thiol/yl-thiomethyl/yl-thioethyl/yl-thiobenzyl and yl-thioglycolic acids were prepared as possible biologically active agents. The infrared, nuclear magnetic resonance (^{1}H-NMR and ^{13}C-NMR), mass spectra and elemental analysis of these compounds are reported


Cover And Contents Jan 2003

Cover And Contents

Turkish Journal of Botany

No abstract provided.


Cover And Contents Jan 2003

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.


Cover And Contents Jan 2003

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.


Application Of A Three-Stage Sequential Extraction Procedure For The Determination Of Extractable Metal Contents In Highway Soils, Şeri̇fe Tokalioğlu, Şenol Kartal, Gökhan Bi̇rol Jan 2003

Application Of A Three-Stage Sequential Extraction Procedure For The Determination Of Extractable Metal Contents In Highway Soils, Şeri̇fe Tokalioğlu, Şenol Kartal, Gökhan Bi̇rol

Turkish Journal of Chemistry

A sequential extraction procedure, a three-step protocol proposed by the Standards, Measurements and Testing programme (SM & T--formerly BCR) of the European Union, was applied to soil samples for the determination of metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn). This procedure provides measurements of extractable metals from media such as acetic acid (0.11 mol L^{-1}), hydroxylammonium chloride (0.1 mol L^{-1}) and hydrogen peroxide (8.8 mol L^{-1}) plus ammonium acetate (1 mol L^{ - 1}), which are exchangeable, reducible and oxidisable metals, respectively. Analyses were carried out using flame atomic absorption spectrometry (FAAS). The results obtained from …