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2006

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Articles 2761 - 2790 of 3150

Full-Text Articles in Life Sciences

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 …

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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 …

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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.

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Rnf Genes In Purple Sulfur Bacterium Allochromatium Vinosum, H. Benan Di̇nçtürk, Volkan Demi̇r Jan 2006

Rnf Genes In Purple Sulfur Bacterium Allochromatium Vinosum, H. Benan Di̇nçtürk, Volkan Demi̇r

Turkish Journal of Biology

Allochromatium vinosum is a photosynthetic, diazotrophic purple sulfur bacterium that oxidizes reduced sulfur compounds hydrogen sulfide, elemental sulfur and thiosulfide. In this article, we report the presence of rnf genes in Allochromatium vinosum, some of which have been reported to take part in nitrogen fixation in some species.

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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 …

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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 …

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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 …

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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 …

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Antimicrobial Activities Of The Extracts Of Marine Algae From The Coast Of Urla (İzmir, Turkey), İnci̇ Tüney, Bi̇lge Hi̇lal Çadirci, Di̇lek Ünal, Atakan Sukatar Jan 2006

Antimicrobial Activities Of The Extracts Of Marine Algae From The Coast Of Urla (İzmir, Turkey), İnci̇ Tüney, Bi̇lge Hi̇lal Çadirci, Di̇lek Ünal, Atakan Sukatar

Turkish Journal of Biology

Methanol, acetone, diethyl ether, and ethanol extracts of 11 seaweed species from the coast of Urla were tested in vitro for their antimicrobial activities against Candida sp., Enterococcus faecalis, Staphylococcus aureus, Streptococcus epidermidis, Pseudomonas aeruginosa, and Escherichia coli with the disc diffusion method. Diethyl ether was the best solution for extracting the effective antimicrobial materials from the algae species used in this experiment, with the exception of D. linearis, for which ethanol was the most effective extraction solution. Diethyl ether extracts of fresh Cystoseira mediterranea, Enteromorpha linza, Ulva rigida, Gracilaria gracilis, and Ectocarpus siliculosus showed effective results against all test …

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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, …

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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 …

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Antibacterial Activity Of Four Plant Extracts Used In Palestine In Folkloric Medicine Against Methicillin-Resistant Staphylococcus Aureus, Bassam Abu-Shanab, Ghaleb Mohammad Adwan, Naser Jarrar, Awni Abu-Hijleh, Kamel Adwan Jan 2006

Antibacterial Activity Of Four Plant Extracts Used In Palestine In Folkloric Medicine Against Methicillin-Resistant Staphylococcus Aureus, Bassam Abu-Shanab, Ghaleb Mohammad Adwan, Naser Jarrar, Awni Abu-Hijleh, Kamel Adwan

Turkish Journal of Biology

Ethanolic and hot water extracts from 4 different plant species used in Palestine in popular medicine for the treatment of several ailments of microbial and non-microbial origin were evaluated for potential antimicrobial activity against methicillin-resistant Staphylococcus aureus (MRSA). Both water and ethanol extracts of Mentha longifolia, Melissa officinalis and Rosa damascena were effective on MRSA. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of the ethanolic extract of M. longifolia and M. officinalis were in the range of 3.125 to 12.50 mg/ml and 12.50 to 25.00 mg/ml, respectively. The ethanolic extract with the greatest antimicrobial activity was …

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Effectiveness Of The Entomopathogenic Nematodes Heterorhabditis Bacteriophora And Steinernema Feltiae Against Tenebrio Molitor (Yellow Mealworm) Larvae In Different Soil Types At Different Temperatures, Alper Susurluk Jan 2006

Effectiveness Of The Entomopathogenic Nematodes Heterorhabditis Bacteriophora And Steinernema Feltiae Against Tenebrio Molitor (Yellow Mealworm) Larvae In Different Soil Types At Different Temperatures, Alper Susurluk

Turkish Journal of Biology

The efficiency of the entomopathogenic nematodes Steinernema feltiae Tur-S3 and Heterorhabditis bacteriophora Tur-H2, isolated in Turkey, against larvae of Tenebrio molitor L. was investigated in different soil type and temperature conditions. Sterilized and non-sterilized silver sand, clay-loam soil, and compost soil were tested, each at 12, 18, and 24 ºC. Temperature had the greatest effect on the mortality of T. molitor larvae caused by both nematode species. The efficiency of the 2 nematodes was greater in sterile than in nonsterile conditions, and was greater in sandy soils than in clay soils. The results showed that Steinernema feltiae was more efficient …

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Isolation And Characterization Of Four Isoinhibitors From Cowpea (Vigna Unguiculata (L.) Walp.) Seeds, Reda Helmy Ahmed Sammour Jan 2006

Isolation And Characterization Of Four Isoinhibitors From Cowpea (Vigna Unguiculata (L.) Walp.) Seeds, Reda Helmy Ahmed Sammour

Turkish Journal of Biology

Four isoinhibitors of trypsin have been isolated from the cowpea, Vigna unguiculata (L.) Walp., in a highly purified state, as indicated by Urea-SDS-polyacrylamide gel electrophoresis, equilibrium chromatography, and amino acid analysis. The amino acid composition was characterized by the absence of free -SH groups, high half-cysteine, and the absence of tryptophan and methionine in isoinhibitors II and III. Isoinhibitor II contained 96 amino acid residues, whereas isoinhibitor III contained 80. Isoinhibitor II had lysine in the reactive site, while isoinhibitor III had arginine. Isoinhibitor IA inhibited trypsin only, while isoinhibitors IB, II, and III inhibited both trypsin and \alpha-chymotrypsin, indicating …

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The Relationship Between Seasonal Variation In Phytoplankton And Zooplankton Densities In Hirfanlı Dam Lake (Kırşehir, Turkey), Tülay Baykal, Selahatti̇n Salman, İlkay Açikgöz Jan 2006

The Relationship Between Seasonal Variation In Phytoplankton And Zooplankton Densities In Hirfanlı Dam Lake (Kırşehir, Turkey), Tülay Baykal, Selahatti̇n Salman, İlkay Açikgöz

Turkish Journal of Biology

Phytoplankton and zooplankton densities in Hirfanlı Dam Lake were studied between July 1999 and June 2000. In addition, phytoplankton biomass was measured using chlorophyll a concentration. The density of Cladocera at the surface and that of Rotifera at the bottom were low in the summer months. For phytoplankton, Cyclostephanos dubius (Fricke) Round was dominant. The variation in the density of organisms did not follow a known pattern. Species composition, seasonal distribution and species density variations show that the lake was advanced mesotrophic. The lake was alkaline and, from time to time, there was an odor in the littoral regions where …

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Chemical Composition Of The Essential Oil Of Salvia Aethiopis L., Medi̇ne Güllüce, Hakan Özer, Özlem Bariş, Di̇mi̇tra Daferera, Fi̇kretti̇n Şahi̇n, Moschos Polissiou Jan 2006

Chemical Composition Of The Essential Oil Of Salvia Aethiopis L., Medi̇ne Güllüce, Hakan Özer, Özlem Bariş, Di̇mi̇tra Daferera, Fi̇kretti̇n Şahi̇n, Moschos Polissiou

Turkish Journal of Biology

The chemical composition of the essential oil obtained by hydrodistillation from the aerial parts of Salvia aethiopis was analyzed by employing GC-MS. Thirty-two components (98.0% of the total oil) were identified in the essential oil of S. aethiopis. The main components of this oil were germacrene D (29.0%), \alpha-copaene (19.8%), \beta-cubebene + \beta-elemene (9.9%), bicyclogermacrene (9.3%), \delta cadinene (8.7%), and \beta-caryophyllene (7.3%).

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Karyological Observation Of Red Mullet (Mullus Barbatus Linnaeus, 1758), Serkan Saygun, İsmi̇han Karayücel, Recep Bi̇rcan Jan 2006

Karyological Observation Of Red Mullet (Mullus Barbatus Linnaeus, 1758), Serkan Saygun, İsmi̇han Karayücel, Recep Bi̇rcan

Turkish Journal of Biology

The number and structure of red mullet chromosomes (Mullus barbatus Linnaeus, 1758) were investigated and the species karyotype was analyzed. Specimens were obtained by trawl from the coast of Zonguldak, Turkey. A colchicine solution, 0.1 mg/g of body weight, was intramuscularly injected dorsally, and intraperitoneally injected ventrally. Slides were prepared from gill and fin epithelial tissues. Results of the conventional staining method showed that this species has 2n = 44 diploid chromosomes.

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Antibacterial Effects Of Nutraceutical Plants Growing In Palestine On Pseudomonas Aeruginosa, Ghaleb Mohammad Adwan, Bassam Abu-Shanab, Kamel Adwan, Farah Abu-Shanab Jan 2006

Antibacterial Effects Of Nutraceutical Plants Growing In Palestine On Pseudomonas Aeruginosa, Ghaleb Mohammad Adwan, Bassam Abu-Shanab, Kamel Adwan, Farah Abu-Shanab

Turkish Journal of Biology

The antibacterial effects of single and combined plant extracts of water, ethanol and methanol for two nutraceuticals utilized in Palestine were studied against multiple drug resistances Pseudomonas aeruginosa using well diffusion method. These plants are Rhus coriaria and Thymus vulgaris. Combinations of these extracts showed an additive action against this pathogen.

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Functionality Of Different Surfactants And Ingredients In Frozen Dough, Ali Asghar, Faqir Muhammad Anjum, Masood Sadiq Butt, Shahzad Hussain Jan 2006

Functionality Of Different Surfactants And Ingredients In Frozen Dough, Ali Asghar, Faqir Muhammad Anjum, Masood Sadiq Butt, Shahzad Hussain

Turkish Journal of Biology

Surfactants are widely used in bakeries as dough strengtheners and dough improvers but there is a wide range of compounds available according to their mode of action that could potentially improve the quality of not only the simple breads and doughs but also of frozen dough. These types of product usually have a short shelf-life when compared with normal bakery products. With the increase in modernization and new trends in food products, consumers are becoming more and more aware and conscious about their diet and therefore their health as well. The quality of frozen dough bakery products could be improved …

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Screening For Cystic Fibrosis: The Importance Of Using The Correct Tools, Uzma Shah, Tariq Moatter Jan 2006

Screening For Cystic Fibrosis: The Importance Of Using The Correct Tools, Uzma Shah, Tariq Moatter

Department of Pathology and Laboratory Medicine

Background: Cystic Fibrosis (CF) is a potentially lethal genetic disorder. The most frequent mutation worldwide in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene is designated as the Delta F508 mutation. This mutation was found in only 33% of Pakistani patients studied. Since the common Pakistani mutations remain to be identified, appropriate screening tools are required to identify disease. Sweat chloride determinations remain the gold standard for diagnosing CF. This study was done to emphasize the importance of using the correct tests.
Methods: The study was conducted at the Aga Khan University Hospital. The CFTR delta F508 mutation was tested …

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M. Leprae Inhibits Apoptosis In Thp-1 Cells By Downregulation Of Bad And Bak And Upregulation Of Mcl-1 Gene Expression, Zahra Hasan, Mussarat Ashraf, Ali Tayyebi, Rabia Hussain Jan 2006

M. Leprae Inhibits Apoptosis In Thp-1 Cells By Downregulation Of Bad And Bak And Upregulation Of Mcl-1 Gene Expression, Zahra Hasan, Mussarat Ashraf, Ali Tayyebi, Rabia Hussain

Department of Pathology and Laboratory Medicine

Background: Virulent Mycobacterium leprae interfere with host defense mechanisms such as cytokine activation and apoptosis. The mitochondrial pathway of apoptosis is regulated by the Bcl-2 family of proteins. Expression of Fas ligand and apoptotic proteins is found in leprosy lesions and M. leprae has been shown to activate pro-apoptotic Bcl-2 genes, Bak and Bax. However, the mechanism by which M. leprae modulates apoptosis is as yet unclear. We investigated expression of apoptotic genes in THP-1 monocytes in response to infection by M. leprae and non-pathogenic M. bovis BCG.
Results: M. leprae did not induce apoptosis in THP-1 cells, while BCG …

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Tannerella Forsythia, A Periodontal Pathogen Entering The Genomic Era, Anne C. R. Tanner, Jacques Izard Jan 2006

Tannerella Forsythia, A Periodontal Pathogen Entering The Genomic Era, Anne C. R. Tanner, Jacques Izard

Department of Food Science and Technology: Faculty Publications

Several questions need to be addressed to evaluate whether Tannerella forsythia is to be considered a periodontal pathogen. T. forsythia has been detected in periodontal health and disease, so could it be a pathogen? The species was not detected in many studies despite finding other putative pathogens, so could it be important in pathogenicity? The challenges of working with T. forsythia include its fastidious and anaerobic growth requirements for cultural detection. Thus, studies associating T. forsythia with periodontal and other oral infections have used noncultural approaches (immunoassays and DNA-based assays) in addition to cultural approaches. We feel …

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Gelatinization And Solubility Of Corn Starch During Heating In Excess Water: New Insights, Wajira S. Ratnayake, David S. Jackson Jan 2006

Gelatinization And Solubility Of Corn Starch During Heating In Excess Water: New Insights, Wajira S. Ratnayake, David S. Jackson

Department of Food Science and Technology: Faculty Publications

Starch gelatinization is associated with the disruption of granular structure causing starch molecules to disperse in water. This study was designed to examine starch granules as they were heated in water, and their resulting morphological, structural, and solubility traits. The results indicate that starch gelatinization is a more complex process than the previously suggested order-to-disorder transition. The energy absorbed by the granules facilitates the rearrangement or formation of new bonds among molecules prior to the temperatures normally associated with the melting of amylopectin crystallites during gelatinization. It is also evident that amylose plays an important role during the initial stages …

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Estrogenic Activity In The Environment: Municipal Wastewater Effluent, River, Ponds, And Wetlands, Nancy W. Shappell Jan 2006

Estrogenic Activity In The Environment: Municipal Wastewater Effluent, River, Ponds, And Wetlands, Nancy W. Shappell

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Estrogenic activity of regional water samples was evaluated. Samples obtained from wetlands and ponds involved in various agricultural land uses, from three river sites over four seasons, and from municipal wastewater effluent held in storage lagoons were evaluated. The estrogen- responsive cell line MCF-7 BOS was used in the E-screen assay to determine 17β-estradiol equivalents (E2 Eq) of water samples extracted by solid-phase extraction. Estrogenic activity in surrounding wetlands and ponds from different land uses was not different, with 10-12 M E2 Eq (0.3 ppt). Estrogenic activity of Red River samples was within the same range as wetland–pond …

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Net Global Warming Potential And Greenhouse Gas Intensity In Irrigated Cropping Systems In Northeastern Colorado, Arvin R. Mosier, Ardell D. Halvorson, Curtis A. Reule, Xuejun J. Liu Jan 2006

Net Global Warming Potential And Greenhouse Gas Intensity In Irrigated Cropping Systems In Northeastern Colorado, Arvin R. Mosier, Ardell D. Halvorson, Curtis A. Reule, Xuejun J. Liu

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The impact of management on global warming potential (GWP), crop production, and greenhouse gas intensity (GHGI) in irrigated agriculture is not well documented. A no-till (NT) cropping systems study initiated in 1999 to evaluate soil organic carbon (SOC) sequestration potential in irrigated agriculture was used in this study to make trace gas flux measurements for 3 yr to facilitate a complete greenhouse gas accounting of GWP and GHGI. Fluxes of CO2, CH4, and N2O were measured using static, vented chambers, one to three times per week, year round, from April 2002 through October 2004 …

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Movements Of European Starlings Captured At A Winter Roost In Omaha, Nebraska, H. Jeffrey Homan, George M. Linz, Garrett W. Unrein, James R. Thiele, John M. Hobbs Jan 2006

Movements Of European Starlings Captured At A Winter Roost In Omaha, Nebraska, H. Jeffrey Homan, George M. Linz, Garrett W. Unrein, James R. Thiele, John M. Hobbs

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

European starlings (Sturnus vulgaris) were using downtown Omaha, Nebraska, as a winter roosting site. We used radio telemetry and leg streamers to track birds in this roost. Between late December 2005 and March 2006, we radio tagged 57 starlings and located them 432 times. We attached leg bands and colored leg streamers to over 1,300 starlings captured at trapping sites within 7 km (4 mi) of the downtown roost. These techniques yielded data on previously unknown sites where starlings gathered to forage, stage, and roost. The maximum distance that a marked bird was observed from the downtown roost …

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Nutrient Uptake Of Maize Affected By Nitrogen And Potassium Fertility In A Humid Subtropical Environment, H. Arnold Bruns, M. Wayne Ebelhar Jan 2006

Nutrient Uptake Of Maize Affected By Nitrogen And Potassium Fertility In A Humid Subtropical Environment, H. Arnold Bruns, M. Wayne Ebelhar

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Nitrogen (N) and potassium (K) fertility management of maize (Zea mays L.) in the humid subtropical Mississippi Delta may differ from a temperate climate because of its use in rotation with cotton (Gossypium hirsutum L.), soil temperatures rarely falling to 0 °C, and heavy winter rains that facilitate nutrient losses. An experiment to determine the [N] (concentration = [ ]), phosphorus [P], [K], calcium [Ca], magnesium [Mg], iron [Fe], manganese [Mn], zinc [Zn], and copper [Cu] and their total contents plant-1 of maize grown in rotation with cotton, using N fertility levels of (134, 179, 224, 269, …

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Effect Of Foliar Applied Plant Elicitors On Microbial And Nematode Populations In The Root Zone Of Potato, H. P. Collins, D. A. Navare, E. Riga, F. J. Pierce Jan 2006

Effect Of Foliar Applied Plant Elicitors On Microbial And Nematode Populations In The Root Zone Of Potato, H. P. Collins, D. A. Navare, E. Riga, F. J. Pierce

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Systemic acquired resistance (SAR) is a process whereby a plant that successfully
resists a pathogen becomes highly resistant to subsequent infection not only by the original pathogen but also by a wide variety of pathogens. Most SAR research has focused on resistance in leaves, so much less is known about the effectiveness of foliar applications of SAR compounds in the protection of plant roots and associated microorganisms in soil. This study was conducted to determine if foliar SAR-inducing applications (BTH or harpin) negatively impact the potato root system beneficial rhizosphere microbial populations and activity or influence pathogenic nematode populations. Foliar …

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Un-Ionized Ammonia Exposure In Nile Tilapia: Toxicity, Stress Response, And Susceptibility To Streptococcus Agalactiae, Joyce J. Evans, David J. Park, Gregg C. Brill, Phillip H. Klesius Jan 2006

Un-Ionized Ammonia Exposure In Nile Tilapia: Toxicity, Stress Response, And Susceptibility To Streptococcus Agalactiae, Joyce J. Evans, David J. Park, Gregg C. Brill, Phillip H. Klesius

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

A series of experiments were conducted to determine the toxicity, behavior, blood glucose stress response, and disease susceptibility in Nile tilapia Oreochromis niloticus following un-ionized ammonia (UIA) exposure. The acute toxicity of un-ionized ammonia to Nile tilapia was measured in a 96-h static test. The median lethal concentration (LC50) was 1.46 mg/L UIA at 24 and 48 h postexposure, 1.33 mg/ L at 72 h postexposure, and 0.98 mg/L at 96 h postexposure. No mortalities were noted in unexposed (0 mg/ L) control fish or fish exposed to 0.5 mg/L UIA. However, 93–100% mortalities were observed within 24 h among …

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International Shipping Of Fumonisins From Maize Extracts On C18 Sorbent, R. T. Riley, O. A. Torres, E. Palencia Jan 2006

International Shipping Of Fumonisins From Maize Extracts On C18 Sorbent, R. T. Riley, O. A. Torres, E. Palencia

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Fumonisins are mycotoxins found in maize. In developing countries, the resources required for analysis are often lacking, and the shipping of maize between countries can be difficult since the importation of plant materials requires permits/ inspection to prevent the entry of pests that frequently infest maize. A simple, safe and legal method for shipping maize extracts to the USA was needed to conduct a survey of fumonisins in Central America. The objective was to develop a method for isolating and shipping maize extracts for fumonisin analysis so as to facilitate a survey of fumonisin exposure. The results indicate that fumonisins …

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