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Transformations Of Middle Eastern Natural Environments: Legacies And Lessons, Jeff Albert, Magnus Bernhardsson, Roger Kenna Jan 1998

Transformations Of Middle Eastern Natural Environments: Legacies And Lessons, Jeff Albert, Magnus Bernhardsson, Roger Kenna

Yale School of the Environment Bulletin Series

No abstract provided.


Unifying Biology: The Evolutionary Synthesis And Evolutionary Biology, Michael Dietrich Jan 1998

Unifying Biology: The Evolutionary Synthesis And Evolutionary Biology, Michael Dietrich

Dartmouth Scholarship

A review of a book by Vassiliki Betty Smocovitis titled Unifying Biology: The Evolutionary Synthesis\r\nand Evolutionary Biology (Princeton: Princeton University Press, 1996).


Non-Volatile Dissolved Organic Iodine In Marine Water, Xianhao Cheng Jan 1998

Non-Volatile Dissolved Organic Iodine In Marine Water, Xianhao Cheng

OES Theses and Dissertations

An analytical scheme for the determination of marine DOI has been established. The concentration of DOI is estimated as total iodine (TI) minus total inorganic iodine (TII). The concentration of total iodine is determined as [special characters omitted] after DOI has been oxidized to inorganic iodine quantitatively by intensive UV-irradiation and all the inorganic iodine in the samples had been converted to [special characters omitted] by the addition of NaClO.

Production of DOI in seawater can be via both non-phytoplankton and phytoplankton related processes. In the former, iodide is converted to DOI. In the latter, most likely, iodate is converted …


The Effect Of Systemic Doxycycline On Alveolar Bone Loss Following Periradicular Surgery, G. Reed Cummings Dec 1997

The Effect Of Systemic Doxycycline On Alveolar Bone Loss Following Periradicular Surgery, G. Reed Cummings

Loma Linda University Electronic Theses, Dissertations & Projects

Studies have shown an average of 0.5 mm to over 1.0 mm of bone loss following full thickness flap reflection. Recent investigations have revealed that the tetracycline family of antibiotics can prevent bone loss. The purpose of this study was to determine the effect of systemic Doxycycline on crestal alveolar bone loss following periradicular surgery in Beagle dogs.

The experiment was divided into two phases. The first phase served as the control (Non-Doxycycline), the second phase as the experiment (Doxycycline). Full thickness flaps were reflected in the mandibular left or right quadrant (control side) of five Beagle dogs. Using a …


The Cellular And Molecular Dynamics Of The Queuosine Modification In Transfer Rna: Definition, Modulation, Deficiencies And Effect Of The Queuosine Modification System, Rana C. Morris Jul 1997

The Cellular And Molecular Dynamics Of The Queuosine Modification In Transfer Rna: Definition, Modulation, Deficiencies And Effect Of The Queuosine Modification System, Rana C. Morris

Theses and Dissertations in Biomedical Sciences

The presence of the queuosine modification in the wobble position of tRNAasn, tRNasp, tRNAhis, and tRNAtyr is associated with a decrease in cellular growth rate, an increase in the ability to withstand environmental stress, and differentiation of pleuripotent cells into mature phenotypes. The loss of this normal modification is strongly correlated with neoplastic transformation and tumor progression of a wide variety of cancers.

The "normal" system for formation of the queuosine modification in tRNA was studied in human fibroblast cell cultures and in mouse, rat and human liver tissues. The queuosine modification system …


Program Abstracts, 109th Session, Iowa Academy Of Science, April 25-26, 1997, Iowa Academy Of Science Apr 1997

Program Abstracts, 109th Session, Iowa Academy Of Science, April 25-26, 1997, Iowa Academy Of Science

Iowa Academy of Science Documents

Presentation abstracts from the annual meeting of the Iowa Academy of Science


Effect Of Media Constituents On In Vitro Culturing Of Cowpea (Vigna Unguiculata) Shoot Tip And Leaf Disk Explants, Mohanjeet S. Brar, Edwin J. Anderson, Teddy E. Morelock, Ronald W. Mcnew Jan 1997

Effect Of Media Constituents On In Vitro Culturing Of Cowpea (Vigna Unguiculata) Shoot Tip And Leaf Disk Explants, Mohanjeet S. Brar, Edwin J. Anderson, Teddy E. Morelock, Ronald W. Mcnew

Journal of the Arkansas Academy of Science

Cowpea is an important legume food crop that is commonly grown in Arkansas and numerous other southern states. The application of biotechnological approaches for the improvement of U.S. cowpea genotypes is currently not possible due to the lack of a regeneration and transformation system. Therefore, the first priority of our research efforts is the development of a plant regeneration system that will facilitate plant transformation studies. In an effort to optimize the media requirements for tissue culturing cowpea, we evaluated the in vitro response of shoot tip and leaf disk explants to various levels of Murashige and Skoog (MS) macro …


Effect Of Af64a On Rat Brain Septo-Hippocampal And Striatal Cholinergic Systems: A Neurochemical And Molecular Analysis, Qing Ivy Fan Jan 1997

Effect Of Af64a On Rat Brain Septo-Hippocampal And Striatal Cholinergic Systems: A Neurochemical And Molecular Analysis, Qing Ivy Fan

Dissertations

No abstract provided.


Potential New Method: A Comparability Study Of M-Coliblue24 And M-Endo Les For The Verified Recoveries Of Total Coliforms And E. Coli, Kevin Robert Geotz Jun 1996

Potential New Method: A Comparability Study Of M-Coliblue24 And M-Endo Les For The Verified Recoveries Of Total Coliforms And E. Coli, Kevin Robert Geotz

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Kevin Robert Goetz on June 10, 1996.


In Vitro Systems And Cultured Cells As Specimens For X-Ray Microanalysis, Godfried M. Roomans, Jarin Hongpaisan, Zhengzhu Jin, Ann-Christin Mörk, Ailing Zhang Apr 1996

In Vitro Systems And Cultured Cells As Specimens For X-Ray Microanalysis, Godfried M. Roomans, Jarin Hongpaisan, Zhengzhu Jin, Ann-Christin Mörk, Ailing Zhang

Scanning Microscopy

In vitro systems and cultured cells are recognized as useful systems in many areas of biomedical research, including X-ray microanalysis. To be reliable, in an vitro system should have an elemental composition close to that of the tissue in situ, react in the same way to stimuli, and retain the in situ regulation of ion transport. In the present paper, four of the most commonly used in vitro systems will be reviewed: incubated tissue slices (liver and pancreas), isolated glands (submandibular gland acini, sweat glands), primary cell cultures (sweat glands, endometrium), and cell lines (the colon cancer cell line …


A Yohimbine-Dependent, Uk14,304 Induced Ion Transient In Ht29 Cells Studied By X-Ray Microanalysis, Wei Zhang, Godfried M. Roomans Mar 1996

A Yohimbine-Dependent, Uk14,304 Induced Ion Transient In Ht29 Cells Studied By X-Ray Microanalysis, Wei Zhang, Godfried M. Roomans

Scanning Microscopy

The response of HT29 cells to α2-adrenoceptor agonists was investigated by X-ray microanalysis. Treatment of the cells with 10 μM UK14,304, an α2-agonist, resulted in a rise of intracellular Cl and Na, suggesting an antisecretory effect. When the cells were exposed to yohimbine or RX821002, both of which are arantagonists, the former had no effect, whereas the latter produced a minor decrease of the cellular Na, Cl and K concentrations. However, when the cells were pretreated with yohimbine, UK14,304 induced a transient change in ion concentrations, which consisted of a rapid increase of intracellular Cl, Na …


Final Environmental Impact Statement For The Bal'diyaka Interpretive Center At Gregory Point On The Oregon Coast In Coos County, Joseph A. Maser Jan 1996

Final Environmental Impact Statement For The Bal'diyaka Interpretive Center At Gregory Point On The Oregon Coast In Coos County, Joseph A. Maser

Environmental Science and Management Faculty Publications and Presentations

The Confederated Tribes of Coos, Lower Umpqua and Siuslaw Indians, in partnership with the Coos Bay District of the Bureau of Land Management (BLM) are proposing to construct and operate an interpretive center near or on the South Coast of Oregon, near Coos Bay. The Bal'diyaka Interpretive Center is envisioned to contain a 51,000 square foot main building, a recreated coastal Indian village, an ethnobotanical interpretive trail, vehicular circulation and parking, and utilities infrastructure.

This Environmental Impact Statement analyzes four alternatives for this proposed interpretive center. The proposed action of the BLM would locate the Bal'diyaka Interpretive Center on Gregory …


Media Effects On Phenotype Of Callus Cultures Initiated From Photoperiod-Insensitive, Elite Inbred Sorghum Lines, H. F. Kaeppler, Jeffrey F. Pedersen Jan 1996

Media Effects On Phenotype Of Callus Cultures Initiated From Photoperiod-Insensitive, Elite Inbred Sorghum Lines, H. F. Kaeppler, Jeffrey F. Pedersen

Department of Agronomy and Horticulture: Faculty Publications

Sorghum (Sorghum bicolor L. Moench) is a crop of worldwide agronomic importance. Routine production of high quality (friable, embryogenic, fast growing) callus cultures is fundamental to tissue culture based genetic study and improvement of sorghum. Genotype by culture medium interactions for sorghum callus growth and morphology have been previously reported. The objective of this study was to identify tissue culture media that would support high quality callus growth across photoperiod insensitive, relatively elite genotypes. Explants from immature inflorescences of 11 sorghum genotypes were cultured on 6 tissue culture media of differing composition. After 3 and 5 months in culture, calli …


Proline Concentration As An Indicator Of The Level Of Salt Tolerance, Philomena Y. Rosalie Jan 1995

Proline Concentration As An Indicator Of The Level Of Salt Tolerance, Philomena Y. Rosalie

Theses : Honours

Each year approximately 20 million hectares of land become affected by increasing salinity. Salt tolerant plants are being used to rehabilitate salt affected areas. Plants use a variety of mechanisms to adapt to salt in their environments. Glycophytes tolerate low to moderate levels of salt while halophytes can tolerate very high salt levels. Many basic physiological attributes have been suggested as important components of a salt tolerant phenotype. These include, influx and/or efflux of ions across plasma membrane and the tonoplast, modification of membrane composition and synthesis of compatible solutes such as soluble carbohydrates, glycine betaines and proline. The project …


The Effects Of Ethanol On The Developing Serotonergic Neurons, Jung-Ae Kim Jan 1995

The Effects Of Ethanol On The Developing Serotonergic Neurons, Jung-Ae Kim

Dissertations

No abstract provided.


Electron Microprobe Analysis Of Electrolytes In Whole Cultured Epithelial Cells, S. Borgmann, M. Granitzer, J. Crabbé, F. X. Beck, W. Nagel, A. Dörge Jul 1994

Electron Microprobe Analysis Of Electrolytes In Whole Cultured Epithelial Cells, S. Borgmann, M. Granitzer, J. Crabbé, F. X. Beck, W. Nagel, A. Dörge

Scanning Microscopy

Microprobe analysis was used to determine electrolyte contents in whole epithelial sheets of A6 cells and to investigate the most critical points of this method. Analysis of dextran standard sections of different thickness revealed that low accelerating voltages of about 10 kV are best suited for whole freeze-dried cells on thick supports, since 5 μm thick sections are not penetrated by 10 kV electrons. Washing of A6 cells for 10 sec with distilled water led to cell swelling of about 40%, but the molar concentration ratios and the concentrations per dry weight (dw) were not altered. Washing for 60 sec …


Analysis Of Competition In Soil Among 2,4-Dichlorophenoxyacetic Acid-Degrading Bacteria, J. O. Ka, William E. Holben, James M. Tiedje Apr 1994

Analysis Of Competition In Soil Among 2,4-Dichlorophenoxyacetic Acid-Degrading Bacteria, J. O. Ka, William E. Holben, James M. Tiedje

Biological Sciences Faculty Publications

Competition among indigenous and inoculated 2,4-dichlorophenoxyacetic acid (2,4-D)-degrading bacteria was studied in a native Kansas prairie soil following 2,4-D additions. The soil was inoculated with four different 2,4-D-degrading strains at densities of 10(3) cells per g of soil; the organisms used were Pseudomonas cepacia DBO1(pJP4) and three Michigan soil isolates, strain 745, Sphingomonas paucimobilis 1443, and Pseudomonas pickettii 712. Following 2,4-D additions, total soil DNA was extracted and analyzed on Southern blots by using a tfdA gene probe which detected three of the strains and another probe that detected the fourth strain, S. paucimobilis 1443, which belongs to a different …


Use Of In Vitro Systems For X-Ray Microanalysis, Jarin Hongpaisan, Ann-Christin Mörk, Godfried M. Roomans Jan 1994

Use Of In Vitro Systems For X-Ray Microanalysis, Jarin Hongpaisan, Ann-Christin Mörk, Godfried M. Roomans

Scanning Microscopy

The use of X-ray microanalysis in human pathology may require the use of cryoprepared tissue. Often it is impossible to carry out freezing of the tissue in an optimal way, and in addition, it is difficult to carry out experiments in living patients. The use of in vitro systems and cell cultures allows separation of the process of tissue removal and the freezing procedure, and also makes testing of pharmacological or toxic substances possible. In experiments with animal tissue it was shown that incubation in a physiological buffer induced significant changes in the concentrations of Na, K, and Cl. In …


Public Attitudes Toward Animal Research: Some International Comparisons, Ralph Pifer, Kinya Shimizu, Linda Pifer Jan 1994

Public Attitudes Toward Animal Research: Some International Comparisons, Ralph Pifer, Kinya Shimizu, Linda Pifer

Attitudes Toward Animal Research Collection

A comparative analysis was made of the public's attitudes toward the use of animals in scientific research in 15 different nations. The intensity of opposition to animal research was found to vary from relatively low levels in Japan and the United States to much higher levels in France, Belgium, and Great Britain. More women than men were opposed to animal research in all 15 nations. Scientific knowledge, or the lack of knowledge, was not found to have a consistent relationship with attitudes toward animal research. Concern about the environment was found to be related to opposition to animal research in …


A Biosystematic Study Of Three Plant Pathogenic Fungi, Richard James Langham Jan 1994

A Biosystematic Study Of Three Plant Pathogenic Fungi, Richard James Langham

Masters Theses

Isolates of Chalara australis, Eucalypt Ceratocystis, and Ceratocystis virescens were grown on Potato Dextrose Agar, Malt Extract Agar, and Czapek Agar and examined as part of a biosystematic study on these fungi. Basic micromorphological and macromorphological data on the cultures were recorded and the taxa were found to be morphologically similar. Tissue isolates and single spore isolates were crossed within these taxa and an interspecific cross performed. Chalara australis was found to be either asexual or have only one mating type present in the cultures studied. Eucalypt Ceratocystis was found to have a mating system characteristic of bipolar …


Use Of Cortical Grafts In Hypoxic-Ischemic Brain Injury In Neonatal Rats, M. Hany Elsayed Jan 1994

Use Of Cortical Grafts In Hypoxic-Ischemic Brain Injury In Neonatal Rats, M. Hany Elsayed

Master's Theses

No abstract provided.


Properties Of A Novel Early Lymphoid Activation Gene (Elag) Isolated From A Hodgkin's-Disease Cell Line, John Scott Bennett Jan 1994

Properties Of A Novel Early Lymphoid Activation Gene (Elag) Isolated From A Hodgkin's-Disease Cell Line, John Scott Bennett

Dissertations

No abstract provided.


X-Ray Microanalysis Of Camp-Induced Ion Transport In Ncl-Sg3 Sweat Gland Cells, Ann-Christin Mörk, Godfried M. Roomans Dec 1993

X-Ray Microanalysis Of Camp-Induced Ion Transport In Ncl-Sg3 Sweat Gland Cells, Ann-Christin Mörk, Godfried M. Roomans

Scanning Microscopy

cyclic AMP (cAMP)-induced ion transport in a human sweat gland cell line, NCL-SG3, was investigated by X-ray microanalysis. Stimulation with cAMP caused a decrease in cellular Cl and K content in cells grown on impermeable as well as permeable supports. In cells grown on plastic coverslips or Transwell inserts stimulation with cAMP caused a significant decrease of the Na concentration, but no significant effect on the intracellular Na was seen on cells grown on grids. cAMP had no significant effect on the intracellular Ca concentration.


Can We Landscape To Accommodate Deer? The Tracy Estate Research Garden, Helen H. Heinrich, Susan Predl Oct 1993

Can We Landscape To Accommodate Deer? The Tracy Estate Research Garden, Helen H. Heinrich, Susan Predl

Wildlife Damage Management Conference

The landscape of New Jersey is remarkably rich in vegetation and open space, despite the state's reputation as the nation's most populous state. This landscape is increasingly the product of intense interaction between the white-tailed deer (Odocoileus virginianus) and both native and cultivated vegetation, particularly in suburban communities, where both the whitetail and the vegetation coexist in abundance. Nearly extirpated at the tum of the century due to over-hunting, the state's white-tailed deer population today exceeds 140,000 because habitat is ideal and hunting seasons are carefully regulated. In many instances, where landowners choose not to use hunting as …


A Review Of New Concepts In Renal Stone Research, L. C. Cao, E. R. Boevé, W. C. De Bruijn, W. G. Robertson, F. H. Schröder Jun 1993

A Review Of New Concepts In Renal Stone Research, L. C. Cao, E. R. Boevé, W. C. De Bruijn, W. G. Robertson, F. H. Schröder

Scanning Microscopy

Clinical and basic research in the field of urolithiasis has developed rapidly in recent years. Progress in extracorporeal shock wave lithotripsy (ESWL) and percutaneous nephrolithotomy (PNL) has brought about a revolution in the surgical treatment of urolithiasis and research at the cellular and molecular level is now expanding. In spite of these advances, however, clinical treatment of urolithiasis remains far from satisfactory. Stone recurrence in many patients cannot be predicted and is beyond control of urologists mainly because the mechanisms of stone formation are still not fully understood. It is necessary to study the process of stone formation more intensely …


Separation And Quantification Of Queuine-Modified And Unmodified Transfer Rna Isoacceptors, Jorge Miguel Pereira De Oliveira Da Silva Santos Apr 1993

Separation And Quantification Of Queuine-Modified And Unmodified Transfer Rna Isoacceptors, Jorge Miguel Pereira De Oliveira Da Silva Santos

Chemistry & Biochemistry Theses & Dissertations

The discovery of a base-exchange modification in the first position of the anticodon of four transfer RNA (tRNA) isoacceptor families has been shown to be correlated with a decrease in the rate of cell division in several tumorigenic tissues. This fact led to the hypothesis that wobbling in the anticodon might be a control point wich mediates the rate of translation. A suitable method for separation of different tRNA isoacceptor families had to be created in order to generate a means for quantitatively measuring degrees of this base modification in tRNA. Radio labelled amino acids were used to charge tRNA …


Analysis Of Immediate-Early Gene Expression In The Songbird Brain Following Song Presentation, Claudio Vianna De Mello Jan 1993

Analysis Of Immediate-Early Gene Expression In The Songbird Brain Following Song Presentation, Claudio Vianna De Mello

Student Theses and Dissertations

The song system of oscine songbirds consists of the auditory and motor pathways used in the acquisition and production of learned song and provides powerful material for the study of neuronal and behavioral plasticity, both developmentally and during adult life. The purpose of this thesis is to begin to study molecular mechanisms underlying plasticity in the songbird brain. To test whether genomic mechanisms are involved, the expression of an immediate-early gene (IEG) was studied. The isolation of the canary ZENK homologue is described, an IEG that encodes a zinc-finger protein and which is highly sensitive to growth factors and depolarizing …


The Antidiabetic Agent Pioglitazone Enhances Adipocyte Differentiation Of 3t3-F442a Cells: Regulation Of Glucose Transport Activity And Differentiation-Dependent Gene Expression, Tagrid Sandouk Jan 1993

The Antidiabetic Agent Pioglitazone Enhances Adipocyte Differentiation Of 3t3-F442a Cells: Regulation Of Glucose Transport Activity And Differentiation-Dependent Gene Expression, Tagrid Sandouk

Dissertations

No abstract provided.


A Continuous Culture Model To Examine Factors That Affect Transduction Among Pseudomonas Aeruginosa, Jean Replicon Jan 1993

A Continuous Culture Model To Examine Factors That Affect Transduction Among Pseudomonas Aeruginosa, Jean Replicon

Dissertations

No abstract provided.


X-Ray Microanalysis Of Epithelial And Secretory Cells In Culture, Anne Von Euler, Eva Pålsgård, Christina Vult Von Steyern, Godfried M. Roomans Dec 1992

X-Ray Microanalysis Of Epithelial And Secretory Cells In Culture, Anne Von Euler, Eva Pålsgård, Christina Vult Von Steyern, Godfried M. Roomans

Scanning Microscopy

Cell cultures can be used to study ion transport processes. X-ray microanalysis of cell cultures at the cellular level gives interesting information that can complement electrophysiological and tracer studies. In this paper, methods for culturing and preparing a variety of epithelial and secretory cells (fibroblasts, insulinoma cells, bovine mammary epithelial cells, colon cancer cells) for X-ray microanalysis are presented. Results show that sometimes cell cultures are not homogeneous with respect to ion content or reaction to physiological stimuli. In colon cancer cell cultures, a "high K" and a "low K" cell subpopulation was found; these subpopulations also differed with respect …