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Articles 33661 - 33690 of 39338
Full-Text Articles in Entire DC Network
Cultural Characteristics Of Morchella Esculentamycelium On Some Nutrients, Peri̇han Güler, Oğuz Arkan
Cultural Characteristics Of Morchella Esculentamycelium On Some Nutrients, Peri̇han Güler, Oğuz Arkan
Turkish Journal of Biology
The cultural characteristics of Morchella esculenta mycelium were investigated in potato dextrose agar, malt extract agar and complete medium yeast plates prepared with casein (cas), Casamino Acids (caa), peptone (p) and sodium nitrate (NaNO 3 ). Aerial and vegetative mycelium types were determined in the agar media with cas, caa and p. The third colonial characteristic was observed in the agar media with NaNO 3 . In this media, a colonization increase in circular forms spreading from the centre to the edges was determined. Mycelium colonization periods were 20-24 days in agar media with NaNO 3 .
Bacteriocin Typing Of Some Turkish Isolates Ofpseudomonas Syringae Pv. Phaseolicola, Kiymet Güven
Bacteriocin Typing Of Some Turkish Isolates Ofpseudomonas Syringae Pv. Phaseolicola, Kiymet Güven
Turkish Journal of Biology
Eighty-six Pseudomonas syringae pv. phaseolicola isolates collected from different bean growing areas in Eskişehir were typed for the production of bacteriocin.All the isolates tested produced bacteriocin and 24 bacteriosin groups were determined. No correlation was found between the bacteriocin groups and geographical origin. Authentic isolates of the bacterium representing 3 different races were also tested for bacteriocin production and bacteriocin types did not correlate with the races.
Availibility Of Use Of Total Extracellular Proteins Insds-Page For Characterization Of Gram-Positive Cocci, Sefa Can Saçilik, Özlem Osmanağaoğlu, Ufuk Gündüz, Cumhur Çökmüş
Availibility Of Use Of Total Extracellular Proteins Insds-Page For Characterization Of Gram-Positive Cocci, Sefa Can Saçilik, Özlem Osmanağaoğlu, Ufuk Gündüz, Cumhur Çökmüş
Turkish Journal of Biology
There are no reports in the literature dealing with gram-positive cocci typing by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of extracellular proteins. In this study, Staphylococcus aureus, Staphylococcus warneri, Staphylococcus chromogenes, Micrococcus lysodeikticus and Micrococcus ssp. of the Micrococcaceae family, and Pediococcus halophilus, Streptococcus ssp. and Enterococcus faecalis of the Streptococcaceae family were characterized by SDS-PAGE of whole cell proteins (WCPs) and total extracellular proteins (TEPs). Comparison of SDS-PAGE of WCP profiles with banding patterns produced by that of TEPs provided additional criteria and characteristic banding patterns for the study of the characterization of gram-positive cocci. This method was found …
The Possibility Of Using Crustacean Waste Products(Cwp) On Rainbow Trout ( Oncorhynchus Mykiss)Feeding, Yeşi̇m Özoğul
The Possibility Of Using Crustacean Waste Products(Cwp) On Rainbow Trout ( Oncorhynchus Mykiss)Feeding, Yeşi̇m Özoğul
Turkish Journal of Biology
Crustacean waste product (CWP) generated from the fishing industry could be used in diets for rainbow trout as an alternative animal protein. Some experiments have been undertaken with penaid species, showing that it is possible to partially replace fish meal with CWP in penaid feeds. This study has been designed to assess whether CWP could be used to partially replace fish meal in diets for rainbow trout. The results show that CWP improved the digestibility of the diet, yielding the highest performance, and also that the addition of large amounts of CWP to a low-protein diet did not depress appetite. …
Humerus Primer Ossification Zone Development In Rat Fetuses: A Histological And Histochemical Study, İsmai̇l Üstünel, Gökhan Akkoyunlu, Erdoğan Kocamaz, Ramazan Demi̇r
Humerus Primer Ossification Zone Development In Rat Fetuses: A Histological And Histochemical Study, İsmai̇l Üstünel, Gökhan Akkoyunlu, Erdoğan Kocamaz, Ramazan Demi̇r
Turkish Journal of Biology
In this investigation of the primary ossification zones of 14-18 day-old fetal rat humeri by histological, histochemical and histoenzymatical methods, 30 rat fetuses of the species Rattus norvegicus were used. The humeral diaphysis samples of the fetuses were subjected to alcian blue-heamatoxylin, periodic acid Schiff (PAS)-heamatoxylin, alcian blue-PAS-heamatoxylin, alizarin red and toluidine blue, alkaline phosphatase (ALP), adenosine triphosphatase (ATPase) and acid phophatase (ACP) staining techniques. The results can be summarized as follows: On day 14, no ossification signs were evident yet, whereas on day 15, the initiation of degenerations in some chondrocyte cytoplasms and the formation of osteoblastic cells on …
Determination Of Organophosphate Resistance-Dependent Over-Produce Esterase Allel Type With Electrophoresis In The Malaria Vector Species Anopheles Sacharovi And Culex Pipiens (Diptera: Culicidae), Ümi̇t Lüleyap, Davut Alpteki̇n, Hali̇l Kasap, Mülki̇ye Kasap
Determination Of Organophosphate Resistance-Dependent Over-Produce Esterase Allel Type With Electrophoresis In The Malaria Vector Species Anopheles Sacharovi And Culex Pipiens (Diptera: Culicidae), Ümi̇t Lüleyap, Davut Alpteki̇n, Hali̇l Kasap, Mülki̇ye Kasap
Turkish Journal of Biology
In this study, over-produce esterase allele types dependent on organophosphate resistance in mosquitoes were determined by cellulose acetate gel electrophoresis in the human malaria vector species Anopheles sacharovi and Culex pipiens in Çukurova (Adana). We found A_2 and A_5 allele bands with some unknown and unidentified gel bands in some An. sacharovi field samples, of which some bands seemed to match with over-produce esterase. We identified A_2-B_2 allele types for all the Cx. pipiens samples collected in this study.
Effects Of Endosulfan On The Isolated Sciatic Nerve Of The Frog, Ülkü Çömelekoğlu, Belgi̇n Büyükakilli, Aynur Avci Özge
Effects Of Endosulfan On The Isolated Sciatic Nerve Of The Frog, Ülkü Çömelekoğlu, Belgi̇n Büyükakilli, Aynur Avci Özge
Turkish Journal of Biology
The purpose of this study was to investigate the effect of endosulfan on the isolated sciatic nerve of the frog. The nerve was exposed to 0.5 ppm endosulfan for 60 min and then compound action potentials were recorded extracellulary. The latencies, amplitudes, durations of depolarization and repolarization and threshold voltage were measured (n=30). Conduction velocities were calculated using the nerve lengths and latency values of each nerve. It was observed that values of amplitude and duration of repolarization were significantly higher (p
Effect Of Spaceflight On The Isotonic Contractile Properties Of Single Skeletal Muscle Fibers In The Rhesus Monkey, Robert H. Fitts, Janell R. Romatowski, Cynthia A. Blaser, Lourdes J. De La Cruz, Gwen J. Gettelman, Jeffrey J. Widrick
Effect Of Spaceflight On The Isotonic Contractile Properties Of Single Skeletal Muscle Fibers In The Rhesus Monkey, Robert H. Fitts, Janell R. Romatowski, Cynthia A. Blaser, Lourdes J. De La Cruz, Gwen J. Gettelman, Jeffrey J. Widrick
Biological Sciences Faculty Research and Publications
No abstract provided.
Effect Of Spaceflight On The Maximal Shortening Velocity, Morphology, And Enzyme Profile Of Fast- And Slow-Twitch Skeletal Muscle Fibers In Rhesus Monkeys, Robert H. Fitts, Janell Romatowski, Lourdes De La Cruz, Jeffrey J. Widrick, Dominique Desplanches
Effect Of Spaceflight On The Maximal Shortening Velocity, Morphology, And Enzyme Profile Of Fast- And Slow-Twitch Skeletal Muscle Fibers In Rhesus Monkeys, Robert H. Fitts, Janell Romatowski, Lourdes De La Cruz, Jeffrey J. Widrick, Dominique Desplanches
Biological Sciences Faculty Research and Publications
No abstract provided.
Threatened Fishes Of The World: Chasmistes Liorus Jordan, 1878 (Catostomidae), Mike Whitney, Mark C. Belk
Threatened Fishes Of The World: Chasmistes Liorus Jordan, 1878 (Catostomidae), Mike Whitney, Mark C. Belk
Faculty Publications
Common name: June sucker.
Effects Of Height And Vegetation On Success Of Bird Nests In Maritime Forests, Sharon M. Defalco
Effects Of Height And Vegetation On Success Of Bird Nests In Maritime Forests, Sharon M. Defalco
College of Graduate Studies: Theses & Dissertations (1964–2006)
Nest predation is an important source of mortality in songbirds and may contribute to declines in Neotropical migrants. I used artificial nests baited with fresh Japanese Quail and Zebra Finch eggs in conjunction with observations of natural nests to quantity the ettects ol nest height and vegetation on nest predation on St. Catherine's Island, a barrier island in southeast Georgia. Because of intense browsing by white-tailed deer. I predicted that lower, more exposed nests would be least successful. Artificial nests (n = 389) were placed in the field, and natural nests (n = 49) were observed, durintz April and May …
The Abundance And Distribution Of Arthropods From Sandstone Outcrops In Coffee County, Georgia, F. Michael Mcaloon
The Abundance And Distribution Of Arthropods From Sandstone Outcrops In Coffee County, Georgia, F. Michael Mcaloon
College of Graduate Studies: Theses & Dissertations (1964–2006)
Broxton Rocks Nature Preserve, a 1,233-hectare preserve containing late Pleistocene sandstone (Altamaha grit) outcrops of various sizes and topographies in a conifer-dominated loblolly pine - hardwood forest, represents a unique habitat to the coastal plain of Georgia. Using modified pitfall traps, I sampled arthropods in four subhabitats (bare rock, lichens, ecotone, wiregrass) at Broxton Rocks between January and November 1999. A total of 312,006 arthropods belonging to four classes (Arachnida, Diplopoda, Chilopoda, Insecta) represented by 24 orders was trapped. The numbers of arthropods varied among habitat types, and over the collection dates (P
Characterizing The Role Of Mapk Phosphates In Plants, Laura Asakura
Characterizing The Role Of Mapk Phosphates In Plants, Laura Asakura
Honors Theses
Mitogen Activated Protein Kinase (MAPK) pathways e ubiquitous ongst eukaryotes, involved in the signal transduction of various external stimuli to the nucleus. In plants, only MAPK pathways related to pathogen- and stress-related responses have been identified. It has been proposed that another MAPK pathway exists in plants, one that is similar to animal MAPK pathways and postulated to connect the regulation of cell growth and the actions of hormones auxin, cytokinin, and gibberellin. In order to establish whether a link exists between the MAPK pathway and hormone signaling in plants, the role of MAPK phosphatases (MKP) on hormone signaling was …
Temporal And Spatial Variations In Macrofouling Of Silicone Fouling-Release Coatings, Christina Darkangelo Wood, Kathryn Truby, Judith Stein, Deborah Wiebe, Eric Holm, Dean Wendt, Celia Smith, Christopher Kavanagh, Jean Montemarano, Geoff Swain, Anne Meyer
Temporal And Spatial Variations In Macrofouling Of Silicone Fouling-Release Coatings, Christina Darkangelo Wood, Kathryn Truby, Judith Stein, Deborah Wiebe, Eric Holm, Dean Wendt, Celia Smith, Christopher Kavanagh, Jean Montemarano, Geoff Swain, Anne Meyer
Biological Sciences
Nontoxic, low surface free energy silicone coatings having reduced biofouling adhesion strength have been developed as an alternative to antifouling paints. Silicone coatings permit macrofouling to adhere; however, fouling can be removed easily by water pressure or light scrubbing. One of the current methods used to evaluate the performance of non-toxic silicone fouling-release coatings relies heavily on fouling coverage. The organismal community structure as well as total coverage can affect the ease of fouling removal from these coatings. This paper explores fouling coverage and organismal adhesion over time. Long-term fouling coverage data were collected at four sites (in Massachusetts, Hawaii …
Dimensionless Invariants For The Optimal Size (Age) Of Sex Change, Eric Charnov, Unnur Skúladóttir
Dimensionless Invariants For The Optimal Size (Age) Of Sex Change, Eric Charnov, Unnur Skúladóttir
Biology Faculty & Staff Publications
Optimization models have been widely and successfully used in evolutionary ecology to predict the attributes of organisms; perhaps the greatest quantitative success is in the area of sex allocation (sex ratio, sperm versus eggs for hermaphrodites, time as a male [female] for a sex changer), where the fact of having only one mother and one father makes Darwinian fitness a simple product of gain-via-male times gain-via-female. Previous work on sex change used the maximization of this male—female product to successfully predict the direction and age (size) for sex change, and that age has been shown to imply a breeding sex …
Phenotypic Effects Of Leptin In An Ectotherm: A New Tool To Study The Evolution Of Life Histories And Endothermy?, Peter H. Niewiarowski
Phenotypic Effects Of Leptin In An Ectotherm: A New Tool To Study The Evolution Of Life Histories And Endothermy?, Peter H. Niewiarowski
Biology Faculty Research
Leptin is a hormone that regulates energy expenditure and body mass in mammals, and it has attracted considerable attention because of its potential in treating human obesity. Comprehensive data from both pathological and non-pathological systems strongly support a role for leptin in regulating energy metabolism, in thermoregulation and in regulating the onset of puberty. We report here that daily injections of recombinant murine leptin in fence lizards (Sceloporus undulatus) produce phenotypic effects similar to those observed when leptin injections are given to mice, Lizards injected with leptin had body temperatures 0.6 degrees C higher, ate 30 % less food and …
Dg93, A Nodule-Abundant Mrna Of Datisca Glomerata With Homology To A Soybean Early Nodulin Gene, Nancy Fujishige
Dg93, A Nodule-Abundant Mrna Of Datisca Glomerata With Homology To A Soybean Early Nodulin Gene, Nancy Fujishige
Biology Faculty Works
We have isolated a 590-bp full-length cDNA clone designated Dg93, an mRNA that is highly expressed in symbiotic root nodules of the actinorhizal host Datisca glomerata. Dg93 mRNA encodes a deduced polypeptide of 105 amino acids with significant identity (74%) to the soybean (Glycine max) early nodulin (ENOD) gene GmENOD93 (Kouchi and Hata, 1993). Dg93 mRNA is abundant in nodules at 4 weeks post inoculation, the earliest time assayed, and steady-state mRNA levels remain elevated 11 weeks after inoculation. Spatial patterns of Dg93 mRNA expression are complex, with transcript accumulation in the nodule lobe meristem, early infection zone, periderm, and …
Detoxification Of 4-Nitroquinoline 1-Oxide And Benzo(A)Pyrene-4,5-Oxide By Myristicin Induced Glutathione S-Transferase In A/J Mouse Livers, Eduardo Saldivar
Detoxification Of 4-Nitroquinoline 1-Oxide And Benzo(A)Pyrene-4,5-Oxide By Myristicin Induced Glutathione S-Transferase In A/J Mouse Livers, Eduardo Saldivar
Theses and Dissertations - UTB/UTPA
The activities of mouse liver glutathione S-transferases (GSTs) induced by myristicin, the active compound in parsley leaf oil, against the carcinogens 4-nitroquinoline 1-oxide (4NQO) and benzo(a)pyrene-4,5-oxide (BP-4,5-oxide) were studied. A/J mice were treated with three 20 mg doses (one dose every other day) by gavage. Affinity purified liver GST samples from treated animals showed a 7.2-fold increase in activity toward 4NQO when compared with equal amounts of liver samples prepared from the control group. Activity against BP-4,5-oxide was increased 1.8-fold in the experimental group. Experimental samples also showed a significant increase in activity toward the substrates 1-chloro-2,4-dinitrobenzene (CDNB), 2,4-dichloronitrobenzene (DCNB), …
Responses Of Cam Species To Increasing Atmospheric Co2 Concentrations, Philippa M. Drennan
Responses Of Cam Species To Increasing Atmospheric Co2 Concentrations, Philippa M. Drennan
Biology Faculty Works
Crassulacean acid metabolism (CAM) species show an average increase in biomass productivity of 35% in response to a doubled atmospheric CO2 concentration. Daily net CO2 uptake is similarly enhanced, reflecting in part an increase in chlorenchyma thickness and accompanied by an even greater increase in water-use efficiency. The responses of net CO2 uptake in CAM species to increasing atmospheric CO2 concentrations are similar to those for C3 species and much greater than those for C4 species. Increases in net daily CO2 uptake by CAM plants under elevated atmospheric CO2 concentrations reflect increases in both Rubisco-mediated daytime CO2 uptake and phosphoenolpyruvate …
Respiration And Heart Rate At The Surface Between Dives In Northern Elephant Seals, Burney J. Le Boeuf, Daniel E. E. Crocker, Jason Gedamke, J. Grayson, Paul M. Webb, Susanna B. Blackwell, Daniel P. Costa
Respiration And Heart Rate At The Surface Between Dives In Northern Elephant Seals, Burney J. Le Boeuf, Daniel E. E. Crocker, Jason Gedamke, J. Grayson, Paul M. Webb, Susanna B. Blackwell, Daniel P. Costa
Arts & Sciences Faculty Publications
All underwater activities of diving mammals are constrained by the need for surface gas exchange. Our aim was to measure respiratory rate (fb) and heart rate (fh) at the surface between dives in free-ranging northern elephant seals Mirounga angustirostris. We recorded fb and fh acoustically in six translocated juveniles, 1.8-2. 4 years old, and three migrating adult males from the rookery at Ano Nuevo, California, USA. To each seal, we attached a diving instrument to record the diving pattern, a satellite tag to track movements and location, a digital audio tape recorder or acoustic datalogger with an external hydrophone to …
Plant Quality And Spider Predation Affects Grasshoppers (Acrididae): Food-Quality-Dependent Compensatory Mortality, Mark A. Oedekoven, Anthony Joern
Plant Quality And Spider Predation Affects Grasshoppers (Acrididae): Food-Quality-Dependent Compensatory Mortality, Mark A. Oedekoven, Anthony Joern
School of Biological Sciences: Faculty Publications
For insect herbivores, population responses reflect interactions among multiple factors, including abiotic conditions, food plant availability, and biotic interactions guided by food limitation and natural enemies. In this set of field experiments, we evaluated the interactive, dynamic effects of limited food supply and predation from wolf spiders (Lycosidae) on mortality in Ageneotettix deorum, a common grasshopper (Acrididae) from North American sandhills grasslands. We attempted to determine whether the combined effects of food availability and spider predation on mortality were (1) noncompensatory, with the effects of each factor summing to determine ultimate population size, or (2) compensatory, where the effect …
Multiplex Pcr Detection Of Aac(3)Via And Aac(3)Iia Gentamicin Resistance Genes In Bacteria Isolated From Turtle Farms, Hilary Haines
Multiplex Pcr Detection Of Aac(3)Via And Aac(3)Iia Gentamicin Resistance Genes In Bacteria Isolated From Turtle Farms, Hilary Haines
Honors Capstones
No abstract provided.
Reproduction Partitioning In Polygyne Nests Of The Yellowjacket Vespula Squamosa, Stephanie A. Stewart
Reproduction Partitioning In Polygyne Nests Of The Yellowjacket Vespula Squamosa, Stephanie A. Stewart
Masters Theses
No abstract provided.
Richard Goldschmidt And The Crossing-Over Controversy, Michael Dietrich, Marsha Richmond
Richard Goldschmidt And The Crossing-Over Controversy, Michael Dietrich, Marsha Richmond
Dartmouth Scholarship
This book, Perspectives on Genetics, collects more than 100 of these essays, which cumulatively are a history of modern genetics research and its continuing evolution.
From Gene To Genetic Hierarchy: Richard Goldschmidt And The Problem Of The Gene, Michael Dietrich
From Gene To Genetic Hierarchy: Richard Goldschmidt And The Problem Of The Gene, Michael Dietrich
Dartmouth Scholarship
No abstract provided.
An American Obsession: Science, Medicine, And Homosexuality In Modern Society, Michael Dietrich
An American Obsession: Science, Medicine, And Homosexuality In Modern Society, Michael Dietrich
Dartmouth Scholarship
Book review of An American Obsession: Science, Medicine, and Homosexuality in Modern Society by Jennifer Terry, 1999.
Unifying Biology: Evolutionary And Molecular Biology: Science Perspectives On Divine Action, Michael Dietrich
Unifying Biology: Evolutionary And Molecular Biology: Science Perspectives On Divine Action, Michael Dietrich
Dartmouth Scholarship
Book Review of Evolutionary and Molecular Biology: Science Perspectives on Divine Action by Robert J. Russell, William R. Stoeger, SJ and Francisco J. Ayla.
Mechanisms Of Convergence And Extension By Cell Intercalation, Maxellende Ezin
Mechanisms Of Convergence And Extension By Cell Intercalation, Maxellende Ezin
Biology Faculty Works
The cells of many embryonic tissues actively narrow in one dimension (convergence) and lengthen in the perpendicular dimension (extension). Convergence and extension are ubiquitous and important tissue movements in metazoan morphogenesis. In vertebrates, the dorsal axial and paraxial mesodermal tissues, the notochordal and somitic mesoderm, converge and extend. In amphibians as well as a number of other organisms where these movements appear, they occur by mediolateral cell intercalation, the rearrangement of cells along the mediolateral axis to produce an array that is narrower in this axis and longer in the anteroposterior axis. In amphibians, mesodermal cell intercalation is driven by …
Direct And Indirect Effects Of Herbivores On Nitrogen Dynamics: Voles In Riparian Areas, J M. Sirotnak, Nancy J. Huntly
Direct And Indirect Effects Of Herbivores On Nitrogen Dynamics: Voles In Riparian Areas, J M. Sirotnak, Nancy J. Huntly
Biology Faculty Publications
Herbivores can directly increase nitrogen mobility by increasing the quality of organic matter entering the decomposition cycle, but they also may decrease nitrogen mobility by decreasing the biomass of high-nitrogen species in the plant community. We assessed effects of voles (Microtus) on nitrogen dynamics using exclosures in two riparian meadows (Crystal Bench and Blacktail Deer Creek) in Yellowstone National Park (USA). At both sites, the quantity of plant litter was decreased by herbivory following a vole population peak in 1992. At Crystal Bench, removal of voles caused a decrease in the nitrogen concentration and an increase in the C:N ratio …
Organic Carbon Supply And Metabolism In A Near-Stream Groundwater Ecosystem, H. M. Valett, C. C. Dahm, Michelle A. Baker
Organic Carbon Supply And Metabolism In A Near-Stream Groundwater Ecosystem, H. M. Valett, C. C. Dahm, Michelle A. Baker
Biology Faculty Publications
In groundwater ecosystems, in situ primary production is low, and metabolism depends on organic matter inputs from other regions of the catchment. Heterotrophic metabolism and biogeochemistry in the floodplain groundwater of a headwater catchment (Rio Calaveras, New Mexico, USA) were examined to address the following questions: (1) How do groundwater metabolism and biogeochemistry vary spatially and temporally? (2) What factors influence groundwater metabolism? (3) What is the energy source for groundwater metabolism?
At Rio Calaveras, surface discharge and water table elevation increased at the onset of spring snowmelt. Groundwater biogeochemical changes in response to snowmelt included increases in dissolved oxygen …