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Varriation Of Growth Rates In Yellow-Bellied Marmots, Carmen M. Salsbury, K. B. Armitage Jan 2003

Varriation Of Growth Rates In Yellow-Bellied Marmots, Carmen M. Salsbury, K. B. Armitage

Scholarship and Professional Work - LAS

Growth rates of yellow-bellied marmot (Marmota flaviventris) populations over a 32-year period (1965 -1996) varied Significantly with sex, age, location, and year. Overall, males had higher growth rates than females and young and yearlings generally had higher growth rates compared to adults at all locations. The locations varied with respect to elevation and the relationship between elevation and growth rate was complex and likely weather dependent. Low rainfall in late summer was often associated with low growth rates at high elevations where the active season is constrained and delayed by late spring snowmelt compared to low elevations. Growth rates and …

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Seasonal Body Temperature Fluctuations And Energetic Strategies In Free-Ranging Eastern Woodchucks, Carmen M. Salsbury Jan 2003

Seasonal Body Temperature Fluctuations And Energetic Strategies In Free-Ranging Eastern Woodchucks, Carmen M. Salsbury

Scholarship and Professional Work - LAS

During a 2-year period, radiotelemetry was used to continuously monitor body temperature ( T b) of free-ranging woodchucks (Marmota monax) in southeastern Pennsylvania. Hibernation was preceded by daily T b fluctuations ("test drops") of 2-4°C. During hibernation, woodchucks exhibited the characteristic pattern of torpor bouts. Time of arousals occurred randomly, but onset of torpor occurred predominantly between 1800 and 0000 h. Males had shorter hibernation periods (mean of 104.8 days) than did females (121.8 days). Males had shorter torpor bouts, but euthermic bouts were the same length as in females. Males also maintained higher T b during torpor. Overall, the …

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Long-Term Observations Of A Harbor Seal Haul-Out Site In A Protected Cove In Casco Bay, Gulf Of Maine, David Harris Phd, Barbarai Lelli, Sat Gupta Jan 2003

Long-Term Observations Of A Harbor Seal Haul-Out Site In A Protected Cove In Casco Bay, Gulf Of Maine, David Harris Phd, Barbarai Lelli, Sat Gupta

Faculty Publications

We counted the numbers of seals hauled out at low tide on two near-shore ledges in a protected cove in Casco Bay, Gulf of Maine a minimum of 12 times per month, for four years starting in August 1997. The highest mean monthly counts were in August (molting season) and the lowest in either January or February. Counts during pupping season (May and June) were lower than during April or July. As no mother-pup pairs were observed, these ledges are molting but not pupping ledges. Time-series analysis revealed no overall trend in the number of seals present. but did show …

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Are Hummingbirds Facultatively Ammonotelic? Nitrogen Excretion And Requirements As A Function Of Body Size, Todd J. Mcwhorter, Donald R. Powers, Carlos Martinez Del Rio Jan 2003

Are Hummingbirds Facultatively Ammonotelic? Nitrogen Excretion And Requirements As A Function Of Body Size, Todd J. Mcwhorter, Donald R. Powers, Carlos Martinez Del Rio

Faculty Publications - Department of Biological & Molecular Science

Most birds are uricotelic. An exception to this rule may be nectar-feeding birds, which excrete significant amounts of ammonia under certain conditions. Although ammonia is toxic, because it is highly water soluble its excretion may be facilitated in animals that ingest and excrete large amounts of water. Birdpollinated plants secrete carbohydrate- and water-rich floral nectars that contain exceedingly little protein. Thus, nectarfeeding birds are faced with the dual challenge of meeting nitrogen requirements while disposing of large amounts of water. The peculiar diet of nectar-feeding birds suggests two hypotheses: (1) these birds must have low protein requirements, and (2) when …

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Effect Of Sequence On The Conformation Of Dna Holliday Junctions, Franklin A. Hays, Jeff Vargason, P. Shing Ho Jan 2003

Effect Of Sequence On The Conformation Of Dna Holliday Junctions, Franklin A. Hays, Jeff Vargason, P. Shing Ho

Faculty Publications - Department of Biological & Molecular Science

Structures of the DNA sequences d(CCGGCGCCGG) and d(CCAGTACbr5UGG) are presented here as four-way Holliday junctions in their compact stacked-X forms, with antiparallel alignment of the DNA strands. Thus, the ACC-trinucleotide motif, previously identified as important for stabilizing the junction, is now extended to PuCPy, where Pu is either an adenine or guanine, and Py is either a cytosine, 5-methylcytosine, or 5-bromouracil but not thymine nucleotide. We see that both sequence and base substituents affect the geometry of the junction in terms of the interduplex angle as well as the previously defined conformational variables, Jroll (the rotation of the stacked duplexes …

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Central Serotonin And Melanocortin Pathways Regulating Energy Homeostasis, Lora K. Heisler, Michael A. Cowley, Toshiro Kishi, Laurence H. Tecott, Wei Fan, Malcolm J. Low, James L. Smart, Marcelo Rubinstein, Jeffrey B. Tatro, Jeffrey M. Zigman, Roger D. Cone, Joel K. Elmquist Jan 2003

Central Serotonin And Melanocortin Pathways Regulating Energy Homeostasis, Lora K. Heisler, Michael A. Cowley, Toshiro Kishi, Laurence H. Tecott, Wei Fan, Malcolm J. Low, James L. Smart, Marcelo Rubinstein, Jeffrey B. Tatro, Jeffrey M. Zigman, Roger D. Cone, Joel K. Elmquist

Faculty Publications - Department of Biological & Molecular Science

It is now established that the hypothalamus is essential in coordinating endocrine, autonomic, and behavioral responses to changes in energy availability. However, the interaction of key peptides, neuropeptides, and neurotransmitters systems within the hypothalamus has yet to be delineated. Recently, we investigated the mechanisms through which serotonergic (5-hydroxytryptamine, 5-HT) systems recruit leptin-responsive hypothalamic pathways, such as the melanocortin systems, to affect energy balance. Through a combination of functional neuroanatomy, feeding, and electrophysiology studies in rodents, we found that 5-HT drugs require functional melanocortin pathways to exert their effects on food intake. Specifically, we observed that anorectic 5-HT drugs activate pro-opiomelanocortin …

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Lack Of Proopiomelanocortin Peptides Results In Obesity And Defective Adrenal Function But Normal Melanocyte Pigmentation In The Murine C57bl/6 Genetic Background, James L. Smart, Malcolm J. Low Jan 2003

Lack Of Proopiomelanocortin Peptides Results In Obesity And Defective Adrenal Function But Normal Melanocyte Pigmentation In The Murine C57bl/6 Genetic Background, James L. Smart, Malcolm J. Low

Faculty Publications - Department of Biological & Molecular Science

No abstract provided.

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Hypothalamic Proopiomelanocortin Neurons Are Glucose Responsive And Express Katp Channels, Nurhadi Ibrahim, Martha A. Bosch, James L. Smart, Jian Qiu, Marcelo Rubinstein, Oline K. Rønnekleiv, Malcolm J. Low, Martin J. Kelly Jan 2003

Hypothalamic Proopiomelanocortin Neurons Are Glucose Responsive And Express Katp Channels, Nurhadi Ibrahim, Martha A. Bosch, James L. Smart, Jian Qiu, Marcelo Rubinstein, Oline K. Rønnekleiv, Malcolm J. Low, Martin J. Kelly

Faculty Publications - Department of Biological & Molecular Science

Hypothalamic proopiomelanocortin (POMC) neurons are critical for controlling homeostatic functions in the mammal. We used a transgenic mouse model in which the POMC neurons were labeled with enhanced green fluorescent protein to perform visualized, whole-cell patch recordings from prepubertal female hypothalamic slices. The mouse POMC-enhanced green fluorescent protein neurons expressed the same endogenous conductances (a transient outward K current and a hyperpolarization-activated, cation current) that have been described for guinea pig POMC neurons. In addition, the selective -opioid receptor agonist DAMGO induced an outward current (maximum of 12.8 1.2 pA), which reversed at K equilibrium potential (EK), in the majority …

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The Anorexigenic Fatty Acid Synthase Inhibitor, C75, Is A Nonspecific Neuronal Activator, Kanji A. Takahashi, James L. Smart, Hongyan Liu, Roger D. Cone Jan 2003

The Anorexigenic Fatty Acid Synthase Inhibitor, C75, Is A Nonspecific Neuronal Activator, Kanji A. Takahashi, James L. Smart, Hongyan Liu, Roger D. Cone

Faculty Publications - Department of Biological & Molecular Science

C75, a recently derived compound that potently suppresses feeding and induces weight loss, has been proposed to act mainly by inhibiting fatty acid synthase (FAS) in central neurons that control feeding. For example, normal, fasting- associated, hypothalamic increases in neuropeptide Y (NPY)/Agouti-related protein (AGRP) expression and decreases in proopiomelanocortin (POMC)/cocaine and amphetamine regulated transcript (CART) expression were reported to be blocked by C75. Using loose-patch extracellular recording in acute slices, we tested the effect of C75 on anorexigenic POMC neurons and orexigenic NPY neurons of the hypothalamic arcuate nucleus, which were identified by promoter-driven GFP expression, as well as on …

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Regulation Of Proto-Oncogenes Expression In Developmental Epilepsy, Mahnoush Shafiei Jan 2003

Regulation Of Proto-Oncogenes Expression In Developmental Epilepsy, Mahnoush Shafiei

Seton Hall University Dissertations and Theses (ETDs)

Seizures cause selective neuronal cell loss in vulnerable regions such as the hippocampus, cortex, thalamus or substantia nigra (SN) in human or experimental animals. While the HF can propagate seizures, the SN pars reticulata (SNR) regulates the spread ol seizures in an age-dependent fashion, and the pars compacta (SNC) affects extrapyramidal motor control. In mature animals, both structures are wlnerable to seizure-induced damage. In prepubescent rats, seizure susceptibility is reduced and CA 1 region rs primarily affected. The proto-oncogenes, Bcl-2 and Bax, encode specific proteins that inhibit and promote programmed cell death, respectively. In order to determine whether proto-oncogenes are …

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Notes On The Life History Of Asterope Markii Hewitson, 1857 (Nymphalidae), Ryan I. Hill Jan 2003

Notes On The Life History Of Asterope Markii Hewitson, 1857 (Nymphalidae), Ryan I. Hill

College of the Pacific Faculty Articles

No abstract provided.

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The Evolution Of Social And Reproductive Monogamy In Peromyscus, Evidence From Peromyscus Californicus (The California Mouse), David O. Ribble Jan 2003

The Evolution Of Social And Reproductive Monogamy In Peromyscus, Evidence From Peromyscus Californicus (The California Mouse), David O. Ribble

Biology Faculty Research

The genus Peromyscus (deer mice) is an attractive group in which to study the evolution of social and mating behaviours. This genus includes over 50 species (Carleton, 1989) that are widely distributed across North and Central America from coast to coast and from the northern subarctic to Panama (Kirkland & Layne, 1989). The diversity in body sizes among Peromyscus ranges from 13 to 77 g (Millar, 1989) and exceeds that of most other genera. Phylogenetic relationships among species of Peromyscus are relatively well understood (Stangl & Baker, 1984), although the systematics of Peromyscus is an active area of study (e.g., …

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Growth And The Expression Of Alternative Life Cycles In The Salamander Ambystoma Talpoideum (Caudata: Ambystomatidae), Travis J. Ryan, Raymond D. Semlitsch Jan 2003

Growth And The Expression Of Alternative Life Cycles In The Salamander Ambystoma Talpoideum (Caudata: Ambystomatidae), Travis J. Ryan, Raymond D. Semlitsch

Scholarship and Professional Work - LAS

Complex life cycles (CLCs) contain larval and adult phases that are morphologically and ecologically distinct. Simple life cycles (SLCs) have evolved from CLCs repeatedly in a wide variety of lineages but the processes that may underlie the transition have rarely been identified or investigated experimentally. We examined the influence of larval growth rate on the facultative expression of alternative life cycles (metamorphosis or maturation as gill-bearing adults [= paedomorphosis]) in the salamander Ambystoma talpoideum. We manipulated growth rates by altering the amount of food individuals received throughout larval development. The expression of alternative life cycles in A. talpoideum is influenced …

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Complete Nucleotide Sequence Of The Chloroplast Genome From A Leptosporangiate Fer, Adiantum Capillus-Veneris L., Paul G. Wolf, C. A. Rowe, R. B. Sinclair, M. Hasebe Jan 2003

Complete Nucleotide Sequence Of The Chloroplast Genome From A Leptosporangiate Fer, Adiantum Capillus-Veneris L., Paul G. Wolf, C. A. Rowe, R. B. Sinclair, M. Hasebe

Biology Faculty Publications

We determined the complete nucleotide sequence of the chloroplast genome of the leptosporangiate fern, Adiantum capillus-veneris L. (Pteridaceae). The circular genome is 150,568 bp, with a large single-copy region (LSC) of 82,282 bp, a small-single copy region (SSC) of 21,392 bp and inverted repeats (IR) of 23,447 bp each. We compared the sequence to other published chloroplast genomes to infer the location of putative genes. When the IR is considered only once, we assigned 118 genes, of which 85 encode proteins, 29 encode tRNAs and 4 encode rRNAs. Four protein-coding genes, all four rRNA genes and six tRNA genes occur …

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An Ecological Study Of The Spotted Salamander, Ambystoma Maculatum, And Jefferson Salamander, A. Jeffersonianum, In West Virginia, Seth J. Myers Jan 2003

An Ecological Study Of The Spotted Salamander, Ambystoma Maculatum, And Jefferson Salamander, A. Jeffersonianum, In West Virginia, Seth J. Myers

Theses, Dissertations and Capstones

The movements of Spotted Salamanders, Ambystoma maculatum, and Jefferson Salamanders, A. jeffersonianum, in and out of an ephemeral wetland in West Virginia were monitored for one breeding season using a drift fence lined with funnel traps. Significant movements of A. jeffersonianum coincided with rainfall and maximum daily air temperatures reaching a minimum of 5° C. Significant movements of A. maculatum coincided with rainfall and maximum daily air temperatures of at least 10° C. A. jeffersonianum preceded A. maculatum to the breeding site. Males of both species preceded females. The mark-recapture estimate of A. maculatum is 67 males and 25 females. …

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Anorexia, Bulimia, And Crayfish (Or, Why I Study The Pharmacology Of Serotonin Receptors In Glutamatergic Invertebrate Systems), Garrett Sparks Jan 2003

Anorexia, Bulimia, And Crayfish (Or, Why I Study The Pharmacology Of Serotonin Receptors In Glutamatergic Invertebrate Systems), Garrett Sparks

Kaleidoscope

No abstract provided.

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Serpents Of The Ark-La-Tex, Jennifer L. Hollis Jan 2003

Serpents Of The Ark-La-Tex, Jennifer L. Hollis

Presidential Scholars Theses (1990 – 2006)

Slides and notes from a presentation focusing on the snakes of western Arkansas, northeastern Texas, and the Edwards Plateau of central Texas.

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Effects Of A Yec Apologetics Class On Student Worldview, David A. Dewitt, Steve Deckard, Sharon E. Cargo Jan 2003

Effects Of A Yec Apologetics Class On Student Worldview, David A. Dewitt, Steve Deckard, Sharon E. Cargo

Faculty Publications and Presentations

Creationism is a significant component of an overall Christian worldview. A Creation Worldview Test (CWT) was administered to students both before and after completion of a required Apologetics course dealing with the creation/evolution controversy. Pre-test analysis revealed that incoming students tend to have a creationist worldview, however their CWT scores reflected a degree of uncertainty or neutrality on scientific creation and the age of the earth. Post-test analysis showed a significant shift toward a young earth creationist (YEC) view. Implications for teaching apologetics and development of a Creationist worldview based on a Six-day Young Earth perspective were explored and identified.

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Genes And Justice: The Future Of Cloning In The United States - An Analysis Of Ethical, Scientific, & Legal Policy, Marlo Diane Curiel Jan 2003

Genes And Justice: The Future Of Cloning In The United States - An Analysis Of Ethical, Scientific, & Legal Policy, Marlo Diane Curiel

Whittier Scholars Program

This project is a report that surveys the “Biotech Age” expansion and the resulting ethical dilemmas in regards to human cloning while providing an analysis of ethical, scientific, and legal policy. This project is split into sections which discuss the Biotech Age including the Biotech trends, recent legal and scientific breakthroughs, and insight into controversy. This project revolves around the science of cloning human beings, ethical dilemma and legal background. In conclusion a cloning bill is proposed by the scholar.

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Acalypha Deamii : Distribution East Of The Appalachians And Comparative Studies Of Reproductive Anatomy, Patricia A. Truman Jan 2003

Acalypha Deamii : Distribution East Of The Appalachians And Comparative Studies Of Reproductive Anatomy, Patricia A. Truman

Master's Theses

Acalypha deamii (Euphorbiaceae), once thought restricted to flood plains of the Ohio and mid-Mississippi River systems, is now documented from similar habitats in Virginia, Maryland, and West Virginia along the James, Potomac, Rappahannock, Roanoke (Staunton), and Shenandoah rivers. This species is recognized by two-carpellate gynoecia, large seeds, and the routine occurrence of allomorphic flowers and fruits, features sporadically found within this large genus. In addition to documenting the newly recognized range extension of Acalypha deamii, this thesis also investigates the nature of its allomorphic reproductive structures. Staminate, pistillate, fruiting, and allomorphic reproductive structures of Acalypha deamii and a closely related …

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Review Of The Nature Of Nebraska: Ecology And Biodiversity Paul A. Johnsgard, L. Lareesa Wolfenbarger Jan 2003

Review Of The Nature Of Nebraska: Ecology And Biodiversity Paul A. Johnsgard, L. Lareesa Wolfenbarger

Biology Faculty Publications

As a newcomer to Nebraska and someone learning the natural history of this place, I thoroughly enjoyed The Nature of Nebraska. More consequentially, the book will serve as a valuable resource for longtime naturalists, teachers, and others who want to learn about Nebraska's natural history.

Opening with a discussion of geology and ecology, Johnsgard offers a broad overview of Nebraska's ecological diversity, intertwining material on the natural forces that have historically dominated the Plains with a discussion of the anthropogenic forces currently altering the region's unique ecological nature. Approximately half of the book is devoted to more specific descriptions …

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Extremely Halophilic Bacterial Communities In Şereflikoçhisar Salt Lake In Turkey, Meral Bi̇rbi̇r, Cenk Sesal Jan 2003

Extremely Halophilic Bacterial Communities In Şereflikoçhisar Salt Lake In Turkey, Meral Bi̇rbi̇r, Cenk Sesal

Turkish Journal of Biology

Şereflikoçhisar Lake is the largest salt lake in central Turkey. This lake is a major source of solar salt for food, hide and other industries locally. Due to the economic importance of salt obtained from this lake, a microbial survey has been conducted. Six salt and three brine samples were obtained from the lake for physico-chemical and microbiological analyses. Physico-chemical analysis showed that the salts and brines contain sufficient ions and hardness to support extremely halophilic bacteria. The salt collected from the lake contained 10^4-10^6 colony-forming units of extremely halophilic bacteria per gram and brine taken from the lake contained …

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Electrofusion Of Saccharomyces Cerevisiae Auxotrophic Mutants Of Identical Mating Type Using A Laboratory-Made System, Gökhan Coral, Ömer Çolak, M. Ni̇sa Ünaldi, Burhan Arikan Jan 2003

Electrofusion Of Saccharomyces Cerevisiae Auxotrophic Mutants Of Identical Mating Type Using A Laboratory-Made System, Gökhan Coral, Ömer Çolak, M. Ni̇sa Ünaldi, Burhan Arikan

Turkish Journal of Biology

Yeast protoplasts from haploid auxotroph strains DC6 (MAT\alpha) and FY73 (MAT\alpha) were exposed to an inhomogeneous alternating field (AC 200 V/cm). Due to the dielectrophoretic aggregation two or more cells with close membrane contact were formed between the two electrodes. The effects of different DC pulses were investigated to determine critical fusogenic pulse strength. In the results, the maximum fusant cells were obtained only when 8 kV field strengths were applied. These findings showed that the optimum fusogenic pulse strength for yeast protoplasts is 8 kV/cm under our experimental conditions. After fusion, the DNA contents of both hybrid and individual …

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Protein And Dna In Systematic Biology, Selma Gülbi̇tti̇ Onarici, Si̇bel Sümer Jan 2003

Protein And Dna In Systematic Biology, Selma Gülbi̇tti̇ Onarici, Si̇bel Sümer

Turkish Journal of Biology

Since the 1960s, biological macromolecules have occupied an increasingly important role in evolutionary and systematic studies. These biological macromolecules, used as sources of molecular characteristics, are proteins and various types of DNA such as a nuclear genome, nuclear ribosomal DNA, mitochondrial genome, and chloroplast genome. Electrophoresis and immunological techniques are used for generating systematic data from proteins. Generally, electrophoretic methods focus on two general forms of protein data, isozymes and allozymes, while the basis of immunological studies is antigen-antibody reactions. Basic methodologies for using DNA for systematic purposes include DNA-DNA hybridizations, restriction enzyme analysis, sequencing, cloning, PCR and PCR-based fingerprinting …

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Biosorption Of Copper Ions By Caustic Treated Waste Baker's Yeast Biomass, Yekta Göksungur, Si̇bel Üren, Ulgar Güvenç Jan 2003

Biosorption Of Copper Ions By Caustic Treated Waste Baker's Yeast Biomass, Yekta Göksungur, Si̇bel Üren, Ulgar Güvenç

Turkish Journal of Biology

Waste baker's yeast (Saccharomyces cerevisiae) was used as a biosorbent for Cu^{+2} biosorption. The yeast cells were treated with caustic soda, ethanol and heat to increase their biosorption capacity. Among the treatment methods used, the highest copper uptake (21.1 mg g^{-1}) was obtained with the caustic treatment of baker's yeast. The effect of initial copper concentration and pH on biosorption for caustic treated yeast was studied. The highest Cu^{+2} uptake (120.7 mg g^{-1}) was obtained at pH 4.0, for 198.2 mg I^{-1} initial copper ion concentration. The Langmuir model and Freundlich equation were applied to the experimental data and the …

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Cytogenetic Effects Of Copper Chloride On The Root Tip Cells Of Helianthus Annuus L., Hüseyi̇n İnceer, Sema Ayaz, Osman Beyazoğlu, Emi̇ne Şentürk Jan 2003

Cytogenetic Effects Of Copper Chloride On The Root Tip Cells Of Helianthus Annuus L., Hüseyi̇n İnceer, Sema Ayaz, Osman Beyazoğlu, Emi̇ne Şentürk

Turkish Journal of Biology

The cytogenetic effects of copper chloride on root tip cells of Helianthus annuus were investigated. Seeds were treated with 10, 25, 50 and 100 mg/L (ppm) of copper chloride for 24 h. It was found that copper chloride has a marked mitodepressive action on mitosis. Mitotic abnormalities were increased and the mitotic index was decreased depending on the concentration of the copper chloride applied.

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Phospholipid And Triacylglycerol Fatty Acid Compositions From Various Development Stages Of Melanogryllus Desertus Pall. (Orthoptera: Gryllidae), Kadri̇ Bozkuş Jan 2003

Phospholipid And Triacylglycerol Fatty Acid Compositions From Various Development Stages Of Melanogryllus Desertus Pall. (Orthoptera: Gryllidae), Kadri̇ Bozkuş

Turkish Journal of Biology

Phospholipid and triacylglycerol fatty acid compositions from eggs; seventh, eighth and last nymphal stages; and 1, 20- and 40-day-old adult females of the black cricket, Melanogryllus desertus, grown in stock-culture medium under laboratory conditions were analyzed by gas chromatographic methods. A large amount of the fatty acid components at all the development stages of the insects analyzed comprised oleic, linoleic, palmitic and stearic acids. However, palmitoleic, myristic and linolenic acids were also found, at lower levels. There were fluctuations in fatty acid levels at different development stages, such as nymphs and adults. Oleic acid was lower in 1-day-old and older …

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Investigation Of The Antimicrobial Activity Of Some Streptomyces Isolates, Nuretti̇n Şahi̇n, Aysel Uğur Jan 2003

Investigation Of The Antimicrobial Activity Of Some Streptomyces Isolates, Nuretti̇n Şahi̇n, Aysel Uğur

Turkish Journal of Biology

Seventy-four different Streptomyces isolates were obtained from the soils of Muğla province. Antimicrobial activity was determined in 45.9% of the isolates. Fifteen isolates showed strong activity against coagulase-negative Staphylococcus (CoNS). These isolates were extensively studied for their in vitro antimicrobial activity against Gram-positive and Gram-negative bacteria and yeasts. The results indicated that five isolates were highly active against CoNS and yeast with an inhibition zone at ? 20 mm. Three of these isolates were identified as Streptomyces antibioticus (MU106, MU107) and S. rimosus (MU114). The UV spectra of the culture extracts for the active isolates showed absorbance peaks ranging between …

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In Vivo And In Vitro Micrografting Of Pistachio, Pistacia Vera L. Cv. "Siirt", Ahmet Onay, Vedat Pi̇ri̇nç, Fi̇li̇z Adiyaman, Çi̇ğdem Işikalan, Engi̇n Ti̇lkat, Davut Başaran Jan 2003

In Vivo And In Vitro Micrografting Of Pistachio, Pistacia Vera L. Cv. "Siirt", Ahmet Onay, Vedat Pi̇ri̇nç, Fi̇li̇z Adiyaman, Çi̇ğdem Işikalan, Engi̇n Ti̇lkat, Davut Başaran

Turkish Journal of Biology

In this study, the success of in vivo and in vitro micrografts of pistachio (Pistacia vera L. cv. "Siirt") materials are presented. The only variable tested was age (1, 5, 10, and 30-year-old trees). Ten- to 12-day-old axenic seedlings germinated in vitro or seedlings (3 to 5 months-old) grown in pots in vivo were used as rootstocks. Shoot tips collected from the four age classes of mature trees of pistachio were the source of scions. Firm contact between the scion and rootstock was assured through the use of parafilm tape at the graft junction for in vivo micrografts. The in …

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Quorum Sensing In Gram-Negative Bacteria, Gülgün Boşgelmez Tinaz Jan 2003

Quorum Sensing In Gram-Negative Bacteria, Gülgün Boşgelmez Tinaz

Turkish Journal of Biology

It has become increasingly and widely recognised that bacteria do not live as isolated entities but instead exist as communities that exploit elaborate systems of intercellular communication to facilitate their adaptation to changing environmental conditions. A well-characterised example of such intercellular communication is quorum sensing. Quorum sensing depends on the production of diffusible signal molecules termed autoinducers or pheromones, which enable a bacterium to monitor its own cell population density. A variety of physiological processes in a range of bacterial species is regulated by quorum sensing. Examples include bioluminescence, antibiotic biosynthesis, swarming, biofilm differentiation, conjugation and the production of virulence …

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