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Minutes: Council Meeting Oct 2006

Minutes: Council Meeting

Virginia Journal of Science

Minutes of the VAS Council meeting Friday May 26, 2006, 8 - 9:40 AM, at Skelton Conference Center Inn, Virginia Tech, Blacksburg VA. Minutes were edited for publication.


Year-Round Diet Of The Marsh Rice Rat, Oryzomys Palustris, In Virginia Tidal Marshes, Robert K. Rose, Shannon W. Mcgurk Oct 2006

Year-Round Diet Of The Marsh Rice Rat, Oryzomys Palustris, In Virginia Tidal Marshes, Robert K. Rose, Shannon W. Mcgurk

Virginia Journal of Science

The marsh rice rat, Oryzomys palustris, is the dominant semi-aquatic rodent living in tidal marshes of the Virginia coastal plain. Described as highly carnivorous, this species is known to consume a range of animal foods, including crustaceans, mollusks, fish, and arthropods, as well as some plant foods. Analysis of stomach contents from rice rats collected from Eastern Shore tidal marshes throughout an annual cycle revealed that all 103 stomachs contained dicots, 82 percent had monocots, 61 percent had crabs and insects, and 38 percent had snails. Thirty-eight percent of stomachs contained foods in all five categories, no stomach was …


Remarks On The Stability Of Some Size-Structured Population Models I: Changes In Vital Rates Due To Population Only, Mohammed El-Doma Jun 2006

Remarks On The Stability Of Some Size-Structured Population Models I: Changes In Vital Rates Due To Population Only, Mohammed El-Doma

Applications and Applied Mathematics: An International Journal (AAM)

We consider a size-structured population model that has been studied in Calsina et al. (2003). We propose a different approach that provides direct stability results, and we correct a stability result given therein. In addition, we obtain global stability results that have not been given in Calsina et al. (2003).


Analysis Of An Sirs Age-Structured Epidemic Model With Vaccination And Vertical Transmission Of Disease, Mohammed El-Doma Jun 2006

Analysis Of An Sirs Age-Structured Epidemic Model With Vaccination And Vertical Transmission Of Disease, Mohammed El-Doma

Applications and Applied Mathematics: An International Journal (AAM)

An SIRS age-structured epidemic model for a vertically as well as horizontally transmitted disease under vaccination is investigated when the fertility, mortality and removal rates depend on age and the force of infection of proportionate mixing assumption type, and vaccination wanes over time. We prove the existence and uniqueness of solution to the model equations, and show that solutions of the model equations depend continuously on the initial age-distributions. Furthermore, we determine the steady states and obtain an explicitly computable threshold condition, in terms of the demographic and epidemiological parameters of the model; we then study the stability of the …


The Mayfly Newsletter, Peter M. Grant Feb 2006

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.


Acute Effects Of Trichloroacetic Acid On Serum Enzyme Levels And Erythrocyte Carbonic Anhydrase Activity In Rats, Hali̇t Demi̇r, İsmai̇l Çeli̇k Jan 2006

Acute Effects Of Trichloroacetic Acid On Serum Enzyme Levels And Erythrocyte Carbonic Anhydrase Activity In Rats, Hali̇t Demi̇r, İsmai̇l Çeli̇k

Turkish Journal of Biology

The aim of the present study was to investigate the effects of a sublethal dose of trichloroacetic acid (TCA) on serum enzyme levels and erythrocyte carbonic anhydrase (CA) activity in rats under laboratory conditions. Ten Sprague-Dawley albino rats were divided in 2 groups of 5 rats. A 200 mg/kg dose of TCA was administered intraperitoneally to the 5 rats in the treatment group. An equal amount of saline solution was injected into the control group. Serum enzyme levels and erythrocyte CA activity of the rats were measured 1, 3, and 6 h after treatment. According to the results, while the …


Food Restriction Affects Locomotor Activity In Mongolian Gerbils (Meriones Unguiculatus), Alper Karakaş, Erdi̇nç Seri̇n, Bülent Gündüz Jan 2006

Food Restriction Affects Locomotor Activity In Mongolian Gerbils (Meriones Unguiculatus), Alper Karakaş, Erdi̇nç Seri̇n, Bülent Gündüz

Turkish Journal of Biology

The circadian rhythm of the locomotor activity is regulated by at least 2 external pacemakers, environmental photoperiod and food availability. In the present study, the effects of short-term (2 weeks) food restriction on locomotor activity rhythm in adult male and female Mongolian gerbils were investigated. Animals were fed ad libitum with no restriction during the first week of the experiment and their daily ad libitum food consumptions were determined. Then the food was restricted 40% of ad libitum for the next 2 weeks. At constant temperature, locomotor activity was monitored by running wheel in animals exposed to a long photoperiod …


Biological Activities Of The Essential Oil And Methanol Extract Of Achillea Biebersteinii Afan. (Asteraceae), Özlem Bariş, Medi̇ne Güllüce, Fi̇kretti̇n Şahi̇n, Hakan Özer, Hamdullah Kiliç, Hakan Özkan, Münevver Sökmen, Tüli̇n Özbek Jan 2006

Biological Activities Of The Essential Oil And Methanol Extract Of Achillea Biebersteinii Afan. (Asteraceae), Özlem Bariş, Medi̇ne Güllüce, Fi̇kretti̇n Şahi̇n, Hakan Özer, Hamdullah Kiliç, Hakan Özkan, Münevver Sökmen, Tüli̇n Özbek

Turkish Journal of Biology

The present work examined the in vitro antimicrobial and antioxidant activities of the essential oil and methanol extract from Achillea biebersteinii Afan. (Asteraceae). The essential oil exhibited antimicrobial activity against 8 bacteria, 14 fungi and the yeast C. albicans, whereas methanolic extract remained inactive. The antioxidative capacity of the samples was evaluated by using DPPH (2,2-diphenyl-1-picrylhydrazyl) and b-carotene/linoleic acid assays. In both assays, the extract showed better antioxidative capacity than the oil. The extract reduced the stable free radical DPPH with lower IC50 value (89.90 µg/ml) than the oil (8900 µg/ml). In the b-carotene/linoleic acid assay, the samples were not …


Evidence For The Presence Of A Second Electron Donor For The Cytoplasmic Thioredoxins In The Yeast Saccharomyces Cerevisiae, Ahmet Koç, Hüseyi̇n Ç. Karakaya, Ercan S. Ünlü Jan 2006

Evidence For The Presence Of A Second Electron Donor For The Cytoplasmic Thioredoxins In The Yeast Saccharomyces Cerevisiae, Ahmet Koç, Hüseyi̇n Ç. Karakaya, Ercan S. Ünlü

Turkish Journal of Biology

In yeast, the cytoplasmic thioredoxin system is composed of NADPH, thioredoxin reductase-1 (TRR1) and 2 thioredoxin genes (TRX1, TRX2). In this study, using yeast knockout mutants for TRR1, TRX1 and TRX2 genes, the role of the thioredoxin system in methionine sulfoxide reduction was investigated. Cells lacking both TRX1 and TRX2 genes simultaneously were not able to reduce methionine sulfoxides to methionine; however, mutants missing the TRR1 gene were able to reduce methionine sulfoxides to methionine, which showed that electrons could be transferred from NADPH to thioredoxins in the absence of TRR1. Similar results were observed for 3-phosphoadenosine 5-phosphosulfate reduction in …


Antioxidant And Free Radical Scavenging Properties Of Twelve Traditionally Used Indian Medicinal Plants, Farrukh Aqil, Iqbal Ahmad, Zafar Mehmood Jan 2006

Antioxidant And Free Radical Scavenging Properties Of Twelve Traditionally Used Indian Medicinal Plants, Farrukh Aqil, Iqbal Ahmad, Zafar Mehmood

Turkish Journal of Biology

The methanolic crude extracts of 12 traditionally used Indian medicinal plants were screened for their antioxidant and free radical scavenging properties using a-tocopherol and butylated hydroxy toluene (BHT) as standard antioxidants. Antioxidant activity was measured by ferric thiocyanate (FTC) assay and compared with the thiobarbituric acid (TBA) method. Free radical scavenging activity was evaluated using diphenyl picryl hydrazyl (DPPH) radicals. The overall antioxidant activity of Lawsonia inermis was the strongest, followed in descending order by Ocimum sanctum, Cichorium intybus, Piper cubeba, Punica granatum, Allium sativum, Delonix regia, Terminalia chebula, Terminalia bellerica, Mangifera indica, Camellia sinensis, and Trigonella foenum-graecum. Seven plants, …


Characterization Of Rhizobium Sp. Isolated From Bean, Çi̇ğdem Küçük, Meri̇h Kivanç, Engi̇n Kinaci Jan 2006

Characterization Of Rhizobium Sp. Isolated From Bean, Çi̇ğdem Küçük, Meri̇h Kivanç, Engi̇n Kinaci

Turkish Journal of Biology

Thirty nodule isolates from bean (Phaseolus vulgaris L.) grown in Eskişehir were studied for their physiological and biochemical characteristics. Most isolates produced abundant extracellular polysaccharides, tolerated high salt concentration (5% NaCl), grew at a temperature of 42 °C, and synthesized melanin. They were able to grow at pHs ranging from 3.5 to 9.0. The majority of the isolates showed an intrinsic resistance to the antibiotics chloramphenicol (20 and 50 µg ml^{-1}), erythromycin (30 µg ml^{-1}), kanamycin (10 µg ml^{-1}), and streptomycin (40, 80, and 100 µg ml^{-1}). Plasmid DNA profiles of the isolates were identified and it was determined that …


The Efficacy Of Spinosad On Different Strains Of Spodoptera Littoralis (Boisduval) (Lepidoptera: Noctuidae), Hi̇lal Aydin, M. Oktay Gürkan Jan 2006

The Efficacy Of Spinosad On Different Strains Of Spodoptera Littoralis (Boisduval) (Lepidoptera: Noctuidae), Hi̇lal Aydin, M. Oktay Gürkan

Turkish Journal of Biology

The cotton leafworm, Spodoptera littoralis (Boisduval), was collected from commercial cotton production fields in Adana, Turkey, and tested for susceptibility to the insecticide spinosad. The susceptibility of the field strain was also compared to the susceptible strain (S) of S. littoralis. Lethal dose bioassays were performed with third instar larvae using the leaf dip method. The LC50 values for field and susceptible strains were 43.691 and 10.037 ppm, respectively. When LC50 values and 95% confidence intervals were compared with a susceptible laboratory reference strain, the field strain was approximately 4.4-fold less sensitive than the susceptible strain. The present study suggests …


Antimicrobial Properties Of Silene Multifida (Adams) Rohrb. Plant Extracts, Ömer Ertürk, Hati̇ce Kati, Nuretti̇n Yayli, Zi̇hni̇ Demi̇rbağ Jan 2006

Antimicrobial Properties Of Silene Multifida (Adams) Rohrb. Plant Extracts, Ömer Ertürk, Hati̇ce Kati, Nuretti̇n Yayli, Zi̇hni̇ Demi̇rbağ

Turkish Journal of Biology

Specimens of Silene multifida (Adams) Rohrb. were collected in the vicinity of Yomra, Trabzon, Turkey. The fresh plants were air-dried and chopped. This material was extracted with cold chloroform (CHCl3). The chloroform extract was dissolved in dimethyl sulphoxide (DMSO), and, following column chromatography, 6 fractions were obtained. The serial dilutions (0.5, 1, 2, 4 and 10 mg/ml) of these fractions were prepared in 5% Tween 20. The fractions were tested for antimicrobial activity using the agar diffusion technique against 6 bacteria, Bacillus subtilis, Staphylococcus aureus, Esherichia coli, Pseudomonas aeruginosa, Enterobacter cloacae and Proteus vulgaris, and 1 fungus, Candida albicans. Fractions …


Antifeedant And Toxicity Effects Of Some Plant Extracts On Thaumetopoae Solitaria Frey. (Lep.: Thaumetopoeidae), Ömer Ertürk Jan 2006

Antifeedant And Toxicity Effects Of Some Plant Extracts On Thaumetopoae Solitaria Frey. (Lep.: Thaumetopoeidae), Ömer Ertürk

Turkish Journal of Biology

The insecticidal and antifeedant activity of extracts derived from different plants of Aesculus hippocastanum L. (Hippocastanaceae), Viscum album L. (Loranthaceae), Sambucus nigra L. (Caprifoliaceae), Buxus sempervirens L. (Buxaceae), Diospyros kaki L. (Ebenaceae), Artemisia absinthum L. (Compositae), Alnus glutiosa Goertn. (Betulaceae), Origanum vulgare L., (Labiatae), Hypericum androsaemum L. (Hypericaceae) and Ocimum basilicum L. (Labiatae) are reported. The 95% ethanol extracts of plants were tested for toxicity against the third-fourth instar larvae of the Thaumetopoae solitaria Frey. (Lep.: Thaumetopoeidae). Antifeedant activity of the extracts was assessed through tests conducted on the larvae of T. solittaria by the feeding protection bioassay. In the …


Physical And Sensoric Attributes Of Flaxseed Flour Supplemented Cookies, Shahzad Hussain, Faqir Muhammad Anjum, Masood Sadiq Butt, Muhammad Issa Khan, Ali Asghar Jan 2006

Physical And Sensoric Attributes Of Flaxseed Flour Supplemented Cookies, Shahzad Hussain, Faqir Muhammad Anjum, Masood Sadiq Butt, Muhammad Issa Khan, Ali Asghar

Turkish Journal of Biology

Full fat flaxseed flour was supplemented with wheat flour @ 5, 10, 15, 20,25 and 30%. Cookies were prepared from composite flours. Cookies prepared without flaxseed flour were kept as control. The mean quality score of the cookies decreased with the increase in the level of the flaxseed flour supplementation. Colour and crispiness of the cookies showed a declining trend as compared to flavour and texture of cookies. Cookies containing 20% and lower level of the full fat flaxseed flour were acceptable in relation to their overall acceptability. Significant reduction in the spread factor of the cookies was observed. Addition …


Non-Histone Proteins And The Mediator Complex Are Essential For The Transcription Of Hxt2 And Hxt4 Genes In Saccharomyces Cerevisiae, Si̇nem Güzelvardar, Sezai̇ Türkel Jan 2006

Non-Histone Proteins And The Mediator Complex Are Essential For The Transcription Of Hxt2 And Hxt4 Genes In Saccharomyces Cerevisiae, Si̇nem Güzelvardar, Sezai̇ Türkel

Turkish Journal of Biology

Transcriptional activation of HXT2 and HXT4 genes require rapid reorganization of the chromatin structure on the promoter regions of these genes. In this study, it was found that the transcription of HXT2 and HXT4 genes decreased 4- to 7-fold in the yeast strain that does not contain the non-histone proteins 6A and 6B (Nhp6A/B). In addition, results of this research indicated that Nhp6A/B are required for the rapid derepression and activation of HXT2 and HXT4 transcription upon glucose signaling. Furthermore, it was found that Med2p, which provides the connection between the transcriptional activators and the basal transcription factors, is also …


Use Of Gamma Rays To Induce Mutations In Four Pea (Pisum Sativum L.) Cultivars, Cemaletti̇n Y. Çi̇ftçi̇, Asli Di̇vanli Türkan, Khalid Mahmood Khawar, Mehmet Atak, Sebahatti̇n Özcan Jan 2006

Use Of Gamma Rays To Induce Mutations In Four Pea (Pisum Sativum L.) Cultivars, Cemaletti̇n Y. Çi̇ftçi̇, Asli Di̇vanli Türkan, Khalid Mahmood Khawar, Mehmet Atak, Sebahatti̇n Özcan

Turkish Journal of Biology

The study reports a 3-step optimization to find out the effects of cytokinins BAP and TDZ on seed germination and g rays to induce mutations in 4 pea cultivars: Winner, Sprinter, Bolero and Karina. It was observed that germination was independent of the dose of g rays and was mainly affected by the germination capability of the genotypes and doses of BAP and TDZ in the germination medium. Seed germination was better on germination medium containing 50 µM BAP than 10 µM TDZ. Variable rooting was observed on shoots obtained from non-irradiated seeds germinated on MS medium containing 50 µM …


Biological Properties Of Chloro-Salicylidene Aniline And Its Complexes With Co(Ii) And Cu(Ii), Javed Iqbal, Syed Ahmad Tirmizi, Feroza Hamid Wattoo, Muhammad Imran, Muhammad H. Sarwar Wattoo, Shahida Sharfuddin, Shoomaila Latif Jan 2006

Biological Properties Of Chloro-Salicylidene Aniline And Its Complexes With Co(Ii) And Cu(Ii), Javed Iqbal, Syed Ahmad Tirmizi, Feroza Hamid Wattoo, Muhammad Imran, Muhammad H. Sarwar Wattoo, Shahida Sharfuddin, Shoomaila Latif

Turkish Journal of Biology

New complexes of chloro-salicylidene aniline with Co(II) and Cu(II) were synthesised and screened for antibacterial activity against several bacterial strains, namely Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. The metal complexes showed enhanced antibacterial activity compared to uncomplexed ligands.


Primary Structure Of The Carbohydrate-Binding Modules In Various Cellulolytic, Thermophilic, Anaerobic, Ethanol-Producing Isolates, Melek Özkan, Gülay Özcengi̇z Jan 2006

Primary Structure Of The Carbohydrate-Binding Modules In Various Cellulolytic, Thermophilic, Anaerobic, Ethanol-Producing Isolates, Melek Özkan, Gülay Özcengi̇z

Turkish Journal of Biology

In the present study, the carbohydrate-binding module (CBM) coding sequences of the cellulosomes of 13 thermophilic, cellulolytic, anaerobic, ethanol-producing bacterial isolates having some variations in their growth and cellulose degradation capacities were amplified by PCR and then sequenced. The sequence analysis of the amplicons revealed that CBMs of 7 of the isolates including the isolate 7-9-1 with the highest capacity of cellulose degradation in solid medium have 100% identity in both nucleotide and amino acid sequences to CipB of Clostridium thermocellum in the compared regions. On the other hand, CBM of the isolate 7-1-2, also having a high cellulolytic activity, …


Antimicrobial Activity Of Palustriella Commutata (Hedw.) Ochyra Extracts (Bryophyta), Semra İlhan, Fi̇li̇z Savaroğlu, Ferdağ Çolak, Cansu Fi̇li̇k İşçen, Fatma Zerri̇n Erdemgi̇l Jan 2006

Antimicrobial Activity Of Palustriella Commutata (Hedw.) Ochyra Extracts (Bryophyta), Semra İlhan, Fi̇li̇z Savaroğlu, Ferdağ Çolak, Cansu Fi̇li̇k İşçen, Fatma Zerri̇n Erdemgi̇l

Turkish Journal of Biology

The present study describes the antimicrobial activity of 2 extracts of Palustriella commutata (Hedw.) Ochyra, collected from the Sündiken Mountains, Eskişehir, Turkey. These extracts were first prepared with acetone and methanol solvents under reflux. The antimicrobial activity of the extracts was then assessed using the disc diffusion method against 11 bacteria, 1 yeast, and 8 moulds. The antimicrobial test results revealed that the acetone extract had a potential activity against 9 test bacteria. While some gram-positive bacteria tested were sensitive (Bacillus mycoides, B. cereus, B. subtilis, and Micrococcus luteus), all gram-negative bacteria tested (Klebsiella pneumoniae, Yersinia enterocolitica, Pseudomonas aeruginosa, Escherichia …


Hill Reaction, Photosynthesis And Chlorophyll Content In Non-Sugar-Producing (Turnip, Brassica Rapa L.) And Sugar-Producing (Sugar Beet, Beta Vulgaris L.) Root Crop Plants, Manzer H. Siddiqui, M.Masroor A. Khan, M. Nasir Khan, Firoz Mohammad, M. Naeem Jan 2006

Hill Reaction, Photosynthesis And Chlorophyll Content In Non-Sugar-Producing (Turnip, Brassica Rapa L.) And Sugar-Producing (Sugar Beet, Beta Vulgaris L.) Root Crop Plants, Manzer H. Siddiqui, M.Masroor A. Khan, M. Nasir Khan, Firoz Mohammad, M. Naeem

Turkish Journal of Biology

A pot experiment was conducted at the Botany Department, A.M.U., Aligarh, on 2 root crop plants, viz. turnip (Brassica rapa L.), non-sugar-producing and sugar beet (Beta vulgaris L.), sugar-producing, to compare their physiological activity (Hill activity, photosynthesis and chlorophyll content). The seeds of each plant were sown in 20 pots (80% soil + 20% FYM) separately. Two samplings were done at 125 and 140 days (after sowing). Hill activity was measured spectrophotometrically using DCPIP indicator and photosynthesis was assayed by LICOR-6200 Photosynthesis System. Sugar beet gave the maximum leaf-area, Chl a/b ratio, stomatal conductance and photosynthesis rate and Hill activity …


Distribution And Status Of The Southern Bog Lemming, Synaptomys Cooperi, In Southeastern Virginia, Robert K. Rose Jan 2006

Distribution And Status Of The Southern Bog Lemming, Synaptomys Cooperi, In Southeastern Virginia, Robert K. Rose

Virginia Journal of Science

The Dismal Swamp subspecies of the Southern bog lemming, Synaptomys cooperi helaletes, was named based on specimens collected during the 1895-1898 biological surveys conducted in the Dismal Swamp by the US Department of Agriculture. Unknown in the 20th Century until re-discovered in 1980, this small boreal rodent was believed to be restricted to the Great Dismal Swamp of Virginia and North Carolina where the cool damp conditions had permitted it to survive during the Holocene. However, field studies conducted since 1980 have revealed southern bog lemmings to be widespread throughout southeastern Virginia, with populations encompassing an area of more …


Effect Of Gibberellic Acid Spray On Performance Of Tomato, M.Masroor A. Khan, Champa Gautam, Firoz Mohammad, Manzer H. Siddiqui, M. Naeem, M. Nasir Khan Jan 2006

Effect Of Gibberellic Acid Spray On Performance Of Tomato, M.Masroor A. Khan, Champa Gautam, Firoz Mohammad, Manzer H. Siddiqui, M. Naeem, M. Nasir Khan

Turkish Journal of Biology

A pot experiment was performed according to a factorial randomized design at Aligarh to study the effect of 4 levels of gibberellic acid spray (0, 10-8, 10-6 and 10-4 M GA3) on the growth, leaf-NPK content, yield and quality parameters of 2 tomato cultivars (Lycopersicon esculentum Mill.), namely Hyb-SC-3 and Hyb-Himalata. Irrespective of its concentration, spray of gibberellic acid proved beneficial for most parameters, especially in the case of Hyb-SC-3.


Isolation And Characterization Of Lactobacillus Bulgaricus And Lactobacillus Casei From Various Foods, Özlem Turgay, Feryal Erbi̇li̇r Jan 2006

Isolation And Characterization Of Lactobacillus Bulgaricus And Lactobacillus Casei From Various Foods, Özlem Turgay, Feryal Erbi̇li̇r

Turkish Journal of Biology

The aim of this study was to determine Lactobacillus bulgaricus and Lactobacillus casei isolated from yoghurt, different kinds of cheese and a traditional food named 'tarhana' (a fermented food made of a mixture of cereal, yoghurt and thyme), and to determine the antimicrobial activity and antibiotic resistance of these isolates. The identity of the culture was based on characteristics of the strains of Lactobacillus spp. as presented in Bergey's Manual of Determinative Bacteriology, carrying out microscopy (morphology), Gram straining, growth at 15 and 45 °C, and fermentation of different carbon sources and growth in 7.5% NaCl. On the basis of …


Identification Of A Lactic Bacterium Strain Used For Obtaining A Pollen-Based Probiotic Product, Adrian Vamanu, Emanuel Vamanu, Manuel Drugulescu, Ovidiu Popa, Gheorghe Campeanu Jan 2006

Identification Of A Lactic Bacterium Strain Used For Obtaining A Pollen-Based Probiotic Product, Adrian Vamanu, Emanuel Vamanu, Manuel Drugulescu, Ovidiu Popa, Gheorghe Campeanu

Turkish Journal of Biology

This study concerns the identification of a Lactobacillus acidophilus strain by conventional taxonomic techniques (cultivation at different temperatures, different pH values, use of different carbon sources, development on different media and determination of antibioresistance) and by molecular genetic techniques (determination of G and C content). The strain is used for inoculation in media with ground or unground pollen and honey, in order to obtain a probiotic product. Over 72 h the glucid consumption, cell viability and acid production is measured.


Colchicine-Induced Tetraploidy And Changes In Allele Frequencies In Colchicine-Treated Populations Of Diploids Assessed With Rapd Markers In Gossypium Arboreum L., Saeed Rauf, Iftikhar Ahmad Khan, Faroog Ahmad Khan Jan 2006

Colchicine-Induced Tetraploidy And Changes In Allele Frequencies In Colchicine-Treated Populations Of Diploids Assessed With Rapd Markers In Gossypium Arboreum L., Saeed Rauf, Iftikhar Ahmad Khan, Faroog Ahmad Khan

Turkish Journal of Biology

Two cultivars of cotton G. arboreum L. cv. FDH-228 and HK-113 were treated with colchicine solution (1%) with 3 methods of application. Colchicine application at the seedling stage on shoot apex was successful. Tetraploid plants of arboreum (4x = 2n = 52) had larger vegetative, reproductive parts, but less frequent stomata and higher optical density of DNA than their normal diploid counterparts (2n = 26). Results also showed that individuals that escaped the duplicating effects of colchicine although treated, presented significant point mutagenic effects. Randomly Amplified Polymorphic DNA markers were used to evaluate diversity and similarities in populations treated with …


Analysis Of The Effects Of Chromatin Modifying Complexes On The Transcription Of Retrotransposon Ty2-917 In Saccharomyces Cerevisiae, Sezai̇ Türkel, Bükay Yeni̇ce Jan 2006

Analysis Of The Effects Of Chromatin Modifying Complexes On The Transcription Of Retrotransposon Ty2-917 In Saccharomyces Cerevisiae, Sezai̇ Türkel, Bükay Yeni̇ce

Turkish Journal of Biology

Transcription of the yeast retrotransposon Ty2-917 is regulated by a complex set of regulatory regions located both upstream and downstream of the transcription initiation site. In this study, it was found that certain chromatin modifying factors are essential for the transcriptional regulation of Ty2-917. Among the chromatin binding factors tested in this research, non-histone proteins Nhp6A/B have the largest effect on the transcription of Ty2-917. In Dnhp6A/B double mutant yeast strain transcription of Ty2 decreased 20-fold, indicating that these non-histone proteins are essential for the transcription of Ty2-917. Furthermore, it was also shown that the transcription of Ty2-917 decreased by …


Antifungal Activity Of Clerodendrum Inerme (L). And Clerodendrum Phlomidis (L)., Rajasekaran Anitha, Ponnusamy Kannan Jan 2006

Antifungal Activity Of Clerodendrum Inerme (L). And Clerodendrum Phlomidis (L)., Rajasekaran Anitha, Ponnusamy Kannan

Turkish Journal of Biology

The ethyl acetate and hexane extracts of leaves and stems of Clerodendrum inerme and Clerodendrum phlomidis (Verbenaceae) were screened for antifungal activity. Both ethyl acetate and hexane extracts of C. phlomidis stem and leaf exhibited appreciable inhibition on all the studied plant and human pathogenic fungi. However, leaf hexane extract (1 mg/ml) of C. inerme inhibited the plant pathogenic fungi better than the human dermatophytes.


Effects Of Sequential Sub-Culturing On The Survival And Enzyme Activity Of Neocallimastix Hurleyensis, Mehmet Sai̇t Eki̇nci̇, Emi̇n Özköse, İsmai̇l Akyol Jan 2006

Effects Of Sequential Sub-Culturing On The Survival And Enzyme Activity Of Neocallimastix Hurleyensis, Mehmet Sai̇t Eki̇nci̇, Emi̇n Özköse, İsmai̇l Akyol

Turkish Journal of Biology

This study investigated the long-term adaptation of a rumen anaerobic fungus, Neocallimastix hurleyensis, grown on each of 3 different substrates as the sole energy source. The rumen anaerobic fungus was cultivated on Avicel, Xylan and glucose for up to 31 subcultures, and its survival and enzymatic activity were monitored. The fungus was able to survive on each of these substrates. Significant increases in the xylanase, avicelase and carboxymethylcellulase (CMCase) activities of N. hurleyensis were observed after 31 subcultures on Avicel and Xylan. However, there was a significant decrease in these enzyme activities after 31 consecutive subcultures of the N. hurleyensis …


Biochemical Responses Of Dimorphic Seeds Of Arthrocnemum Indicum Willd. During Germination, Inhibition, And Alleviation Under Saline And Non-Saline Conditions, Zamin Shaheed Siddiqui Jan 2006

Biochemical Responses Of Dimorphic Seeds Of Arthrocnemum Indicum Willd. During Germination, Inhibition, And Alleviation Under Saline And Non-Saline Conditions, Zamin Shaheed Siddiqui

Turkish Journal of Biology

Dimorphic seeds of Arthrocnemum indicum (a halophytic shrub) exhibit diverse germination responses following salinity treatment and subsequent exposure to growth regulators by adjusting their physiological and biochemical processes. The present study examined the effects of 24-h and 72-h NaCl treatment on germination, germination velocity, and the associated biochemical changes in protein and RNA contents of 2 seed morphs, and compared these effects after transfer into distilled water or 10 mM thiourea solution. Treatment for 24 and 72 h in NaCl solution induced a significant reduction in the rate of germination and final percent germination of both seed morphs. No germination …