WWW.DISSERTATION.XLIBX.INFO
FREE ELECTRONIC LIBRARY - Dissertations, online materials
 
<< HOME
CONTACTS



Pages:     | 1 |   ...   | 25 | 26 || 28 | 29 |   ...   | 112 |

«Strengthening the Nation through Diversity, Innovation & Leadership in STEM San Antonio,Texas · October 3-6, 2013 Get Connected! Connect with the ...»

-- [ Page 27 ] --

1 Triclosan, an antimicrobial that is used in a variety of products such as plastics and toothpastes, can be found in freshwater streams used for irrigation water. In this study, the objective was to determine the potential effects of Triclosan on tomato plant growth, Triclosan accumulation in plant tissues, and heterotrophic bacterial counts. In a greenhouse study, 12 tomato plants were grown for 14 weeks and irrigated weekly with the following concentrations of Triclosan: 0.00, 0.015, 0.15, and 1.5 µg/l. Harvested plants were sectioned into roots, shoots, leaves, and fruits before drying to obtain biomass and then pulverized prior to a solid phase extraction using a 1:1 methanol-to-acetone solution. Extractants were concentrated prior to GC-MS analysis. Both rhizosphere and bulk soil bacteria were enumerated by serial dilution plating on R2A. Total plant biomass showed a decreasing trend with increasing Triclosan concentrations, but was not significant (p 0.05). Initial extractions indicate an increase in Triclosan concentrations with treatment concentrations. Rhizosphere bacterial counts were not significantly different (p = 0.4552) between treatments with an overall mean of 3.8 x 108 CFU/g dry soil. However, bulk soil heterotrophic bacterial counts were significantly higher (p = 0.0002) in the higher Triclosan treatments (0.15 and 1.5 µg/l) with 3.7 x 107 and 4.1 x 107 CFU/g dry soil, respectively. These data indicate that Triclosan may potentially decrease plant growth while increasing Triclosan contamination of a crop plant. Additionally, Triclosan may be selecting for resistant soil bacteria while not affecting rhizobacteria due to a plant-microbe interaction.

SAT-163

EXAMINING THE EFFECTS OF WARMING ON POPULATION DENSITIES OF DAPHNIA PULEX

Aracely Tellez, Mariana Vargas, Vanessa L. Lougheed.

University of Texas at El Paso, El Paso, TX.

With warming in the Arctic, more nutrients are being released from thawing permafrost into Arctic aquatic ecosystems.

The impact of these changes on aquatic food webs is largely unknown. Zooplankton are abundant in Arctic tundra ponds; recent studies have indicated changes in these communities as ponds warm and become more nutrient rich. This study was done to examine the effects of nutrient enrichment and warming on algal community structure and consequently on Daphnia pulex reproduction. Daphnia pulex, an organism commonly found in the Arctic and generally used to determine the quality of water for living organisms, was grown at 2 different temperatures (21 and 25 °C) in arctic algae cultures. Reproduction, mortality, and growth rates of Daphnia, as well as gross taxonomic algal composition were measured. We hypothesized that nutrient enrichment and warming would produce a cascading effect on aquatic organisms. Preliminary results show distinct differences among treatments. Daphnia kept at 21 °C, did not increase in numbers although algae abundances increased substantially. Warmer cultures, however, had inconsistent numbers throughout the experiment. Populations of Daphnia tripled within days then suddenly dropped the numbers to zero while algae also declined in numbers. Preliminary results from nutrient enrichment indicated phosphorus as a limiting factor for algal growth, having a direct impact on D. pulex growth and reproduction.

These results support field observations where increased nutrient levels and algal biomass in Arctic tundra ponds lead to changes at higher trophic levels. Future studies will look at both warming and nutrient effects in a factorial experimental design.

SAT-169

USE OF SOIL BACILLI FOR BIOCONTROL OF CHILI FUNGAL PATHOGENS

Deidre Pine, Stephen Hanson.

NEW MEXICO STATE UNIVERSITY, LAS CRUCES, NM.

Phytophthora capsici and Verticillium dahlia are some of the leading causes of loss in chili pepper production in the Southwest. Phytophthora capsici is part of the genus Oomycetes (water mold) and which causes huge economic loss on crops worldwide, along with Verticillium dahlia. The absence of natural resistance to these pathogens as well as

–  –  –

FRI-169

BIOACCUMULATION OF SYNTHETIC MUSK FRAGRANCES IN NORTHERN DIAMONDBACK TERRAPINS

(MALACLEMYS TERRAPIN) OF JAMAICA BAY, NEW YORK, UNITED STATES

Lisa McBride1, Andrew Heyes2, Christopher Rowe2, Russell Burke3, Cheryl Clark2.

New Mexico Highlands University, Las Vegas, NM, 2Chesapeake Biological Laboratory, University of Maryland Center 1 for Environmental Sciences, Solomons, MD, 3Hofstra University, Hempstead, NY.

Synthetic musk fragrances are found in almost all scented personal care products. They have been measured in water, air, sewage sludge, and various biota from all over the world. However, no studies have measured synthetic musks accumulated by parents and transferred to offspring. Because coastal cities release treated and sometimes untreated sewage effluent “to tide,” research on the impact of personal care products on resident and especially longlived organisms which may accumulate the compounds over long periods of exposure is needed. We selected the diamondback terrapin because it is long lived and inhabits the entire eastern seaboard of the United States across a wide salinity gradient. In this preliminary study, we have targeted 1 nitro musk (musk xylene, [MX]) and 1 polycyclic musk (galaxolide [HHCB]), and are assessing their presence in the eggs of northern diamondback terrapins inhabiting a contaminated site (Jamaica Bay, New York) compared to a less-impacted site in the Patuxent River, Maryland. We have developed a method using gas chromatography-mass spectrometry for analysis of these parent compounds in terrapin eggs. This field based study will be the first step in assessing the degree of exposure of terrapin embryos to synthetic musks accumulated by the parents.





SAT-168

THE EFFECTS OF CAPE IVY ON SOIL MICROBIAL POPULATIONS

Keefah Khalil, Christine Case.

Skyline College, San Bruno, CA.

Cape ivy (Delairea odorata) was introduced from South Africa to the United States in the 1850s and is now the primary threat to biodiversity along the central California coast. Although the decrease in plant diversity following cape ivy infestation has been documented, there is no published research on the effect of cape ivy on soil productivity.

Soil microbes provide essential ecosystem services such as nutrient mineralization. Therefore, the purpose of our study is to determine whether cape ivy disrupts soil microbial ecology. We hypothesize that cape ivy is disrupting microbial populations, which disables native species or gives cape ivy a selective advantage. We are comparing soil microbial activity of cape ivy infested areas with the native coastal scrub community. Soil samples were collected from depths of 0 to 30.5 cm. Community-level physiological profiling employing Biolog Ecoplates was used to compare catabolic activity in the microbial community in cape ivy infested areas with that of the native coastal scrub community. Our preliminary results show that cape ivy does affect the function of soil microbial communities. At 12 cm, catabolic capabilities of the cape ivy associated microbial communities are 7% greater than those of the coastalscrub associated community. Functional diversity in cape ivy soil is 91.4%±7.0 compared to 82.8%±2.1 in the coastalscrub soil at 12 cm. We are examining activities of nitrifying and denitrifying bacteria in the different soil samples. Our results and analysis of functional traits will contribute to understanding the mechanisms by which cape ivy maintains dominance and may help achieve long-term restoration goals.

91 UNDERGRADUATE POSTER ABSTRACTS

SAT-164

EVALUATING THE EFFECTS OF CLIMATE-MEDIATED TEMPERATURE CHANGES ON THE BEHAVIOR AND

PHYSIOLOGY OF YELLOW-BELLIED MARMOTS (MARMOTA FLAVIVENTRIS)

Stephen Morris, Erin Lehmer.

Fort Lewis College, Durango, CO.

Increased global temperatures are predicted to have significant impacts on a number of plant and animal species and these impacts are expected to be most profound for species living in extreme environments. Yellow-bellied marmots (Marmota flaviventris) are hibernating mammals that live at high elevations in Colorado and depend heavily on cold winter temperatures to complete their annual life history events. Our research is focused on evaluating how increased winter temperatures will impact foraging behavior, physiological health, and allostatic loads of marmots living at both high (10,800 ft) and low (7,500 ft) elevations within their geographic ranges. As part of this research, we are sampling marmots in early and late summer to determine their body masses, growth rates, and physical health.

We will also collect blood samples to run an assortment of lab-based analyses intended to determine allostatic load, including estimates of C-reactive protein, glucocortocoid levels, and innate immunity. We will conduct extensive soil and vegetation inventories to determine soil moisture and pH, vegetation biomass and nutrient content, and the timing of plant phenology. This information will be used to determine the extent to which habitat quality differs between marmots at high and low elevation. Finally, we are using temperature-sensitive data loggers to indirectly monitor foraging time, as marmots living in low-quality habitats would presumably spend more time per day foraging compared to their counterparts living in high-quality habitats. Results of this research will provide important information about how climate change impacts plant and animal community dynamics.

FRI-167

METHOD DEVELOPMENT FOR BISPHENOL-A ANALYSIS IN MILK USING STIR BAR SORPTIVE-EXTRACTION

THERMAL-DESORPTION GAS CHROMATOGRAPHY/MASS SPECTROMETRY

Suzanne Apodaca, Wen-Yee Lee.

University of Texas at El Paso, El Paso, TX.

Bisphenol A (BPA) is a man-made environmental contaminant of emerging concern possessing controversial endocrine disruption properties. An increased interest has been seen in its accurate determination in various media order to estimate the exposure to BPA and the associated health risk. The goal of this study was to develop an environmentally friendly (green), sensitive, and efficient method to analyze bisphenol A (BPA) in liquid milk samples.

The technique uses stir bar soprtive extraction (SBSE) and thermal desorption accompanied with gas chromatography and mass spectrometry (GC/MS). For SBSE sample preparation, sodium carbonate served as a pH adjustment agent, acetic acid anhydride as a derivatization agent, mirex as the internal standard, and a preconditioned stir bar were added to a 20 mL volume of sample. After 2 hours of stirring, the stir bar was desorbed in a thermal desorption unit and BPA was analyzed by GC/MS. BPA-spiked, whole-fat milk was used as the model sample matrix. BPA with a concentration range from 0.01 to 10 ug/L (ppb) was added to the milk sample to study the linearity and limit of detection. Different solvent systems (such as methanol) and additive effects were investigated with the SBSE process to determine BPA recovery in milk samples.

SAT-162

A CHARACTERIZATION OF MARSH SEDIMENT AT PRAIRIE WOLF SLOUGH WETLAND

Kathryn Rico, James Montgomery.

DePaul University, Chicago, IL.

Prairie Wolf Slough (PWS) is a restored, farmed wetland in northeastern Illinois that was created to improve the water quality of stormwater runoff entering the North Branch of the Chicago River. Past research has shown that concentrations of soluble reactive and total phosphorous in water that discharges from PWS are higher than the phosphorus concentrations in water entering the wetland. It is important to delineate the various sources of phosphorous in PWS in order to develop a comprehensive phosphorous budget. This project assessed the contribution of phosphorous from sediment/soil being deposited in the marsh. Sediment/soil samples were collected and measured for Mehlich-3 soil test phosphorous, carbon-nitrogen ratio, and particle size. Sediment traps placed in the marsh measured monthly sedimentation rate. Incremental soil samples were taken at 15-cm increments to a total depth of 90 cm from a subset of points along a transect through the center of the wetland; these were analyzed for nitrates, free iron oxides, and soil test phosphorous. Correlation analysis shows weak associations between soil

–  –  –

FRI-165

THE EFFECT OF NONSTEROIDAL ANTI-INFLAMMATORY DRUGS ON THE CELLULAR COMMUNICATION OF A

VIBRIO BACTERIUM

Cindy Barrientos, Teresa Palos.

El Camino College, Torrance, CA.

Pharmaceuticals provide relief from disease signs and symptoms. However, substances that are meant to help people could also be harming the environment. The US Geological Survey has sampled water from 139 streams and found traces of nonprescription drugs in concentrations as high as 17.4 micrograms per liter. It is important to understand the impact of nonprescription drug presence in water-based habitats. This is especially true considering rising pharmaceutical consumption. According to the Consumer Healthcare Products Association, over-the-counter drug retail sales increased to $17.4 billion in 2011. This study investigated the use of Vibrio harveyi, a marine bacterium, as a biological indicator for the impact of over-the-counter drugs. V. harveyi relies on quorum sensing, a form of cell-tocell communication, that uses chemical autoinducers to transmit signals to entire bacterial populations for the control of behavior. A high concentration of the autoinducer triggers bacterial bioluminescence. Bioluminescence generation and changes in bacterial culture brightness were evaluated when exposed to nonsteroidal anti-inflammatory drugs (NSAIDs). The results suggest that ibuprofen had the most detrimental effect, but only when the bacteria were exposed prior to the generation of bioluminescence and not after it had been produced. Both ibuprofen and naproxen had toxic effects at concentrations as little as.054 mg/ml. Aspirin had no effect on bioluminescence or bacterial growth. Additional work should be performed to further study NSAID environmental impact and programs developed to decrease their presence.



Pages:     | 1 |   ...   | 25 | 26 || 28 | 29 |   ...   | 112 |


Similar works:

«Distribution Agreement In presenting this thesis as a partial fulfillment of the requirements for a degree from Emory University, I hereby grant to Emory University and its agents the non-exclusive license to archive, make accessible, and display my thesis in whole or in part in all forms of media, now or hereafter now, including display on the World Wide Web. I understand that I may select some access restrictions as part of the online submission of this thesis. I retain all ownership rights...»

«Planning Perspectives, 21 (January 2006) 23–44 Loose ends: the role of architecture in constructing urban borders in Tel Aviv–Jaffa since the 1920s TALI HATUKA* Department of Urban Studies and Planning, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-7-337, USA (e-mail: hatuka@mit.edu) RACHEL KALLUS* Faculty of Architecture and Town Planning Technion, Israel Institute of Technology, Haifa 32000, Israel (e-mail: arkalsu@tx.technion.ac.il) TaliHatuka 0 1000002006...»

«Alooideae—Asphodelaceae And The Genera Thereof by M Bruce Bayer Reprinted from Alsterworthia International Special Issue No 4 My fascination with Haworthia has presented me with many problems in the way the genera in the Alooideae have been discussed, appraised and modified in and subsequent to G. D. Rowley's analysis (1967). Parr (1971) coalesced Astroloba, Haworthia and Poellnitzia and I refuted this in 1972 when I also wrote a rebuttal of Rowley's paper. My remarks did not deter Mrs...»

«Observation of abundant heat production from a reactor device and of isotopic changes in the fuel Giuseppe Levi Bologna University, Bologna, Italy Evelyn Foschi Bologna, Italy Bo Höistad, Roland Pettersson and Lars Tegnér Uppsala University, Uppsala, Sweden Hanno Essén Royal Institute of Technology, Stockholm, Sweden October 6, 2014 ABSTRACT New results are presented from an extended experimental investigation of anomalous heat production in a special type of reactor tube operating at high...»

«CONTENTS 2 Financial Highlights 4 Chairman‟s Report 5 Chief Executive‟s Report 9 Summary Operating and Financial Overview 11 Directors‟ Report 15 Corporate Governance Report 27 Report of the Remuneration Committee on Directors‟ Remuneration 28 Statement of Directors‟ Responsibilities 30 Independent Auditor‟s Report 32 Presentation of Financial and Certain Other Information 34 Detailed Index* 36 Key Information 42 Principle Risks and Uncertainties 55 Information on the Company 77...»

«SULLIVAN 8t CROMWELL LLP A LIMITED LIABILITY PARTNERSHIP @'l'W JVew gT~ ~ 'I'ELEPHONE: +44 (0)20-7959-8900 ~ rffflld ~~ 0~ FACSIMILE: +44 (0)20-7959-8950 WWW.SULLCROM.COM FRANKFURT • PARIS LOS ANGELES • NEW YORK • PALO ALTO • WASHINGTON, D.C. BEIJING • HONG KONG • TOKYO MELBOURNE • SYDNEY May 20,2015 BY ELECTRONIC MAIL AND FEDERAL EXPRESS Mary J. Kosterlitz, Esq. Chief, Office of Enforcement Liaison Division of Corporation Finance U.S. Securities and Exchange Commission 100 F...»

«Narrative Section of a Successful Application The attached document contains the grant narrative and selected portions of a previously funded grant application. It is not intended to serve as a model, but to give you a sense of how a successful application may be crafted. Every successful application is different, and each applicant is urged to prepare a proposal that reflects its unique project and aspirations. Prospective applicants should consult the Research Programs application guidelines...»

«T H E S TAT E B A R O F CA L I F O R N I A ¿QUÉ DERECHOS TENGO COMO EMPLEADO? GA EN T S O B DATO LOS A L E S G L E A VIDA L DE ¿Qué derechos tengo empleado? como ¿Hay límites sobre lo que me puede preguntar un 1 empleador en una entrevista de trabajo? ¿Puede un empleador pedirme que me someta a 2 una prueba de drogas? ¿Tiene que tener mi empleador un buen motivo 3 para disciplinarme o despedirme? 4 ¿Es ilegal que mi empleador discrimine en contra de mi? ¿Son aplicables las leyes de...»

«RRITJE ALBANIA COMPETITIVE ENTERPRISE DEVELOPMENT PROJECT END OF PROJECT ASSESSMENT February 7, 2014 This publication was produced for review by the United States Agency for International Development. It was prepared by the team of Rritje Albania/ Competitive Enterprise Development (USAID Contract No. 182-C-00-0900002-00) of Chemonics International, Inc. The author’s views expressed in this publication do not necessarily reflect the views of the United States Agency for International...»

«Copyright by Joel Matthew Silverman 2006 The Dissertation Committee for Joel Matthew Silverman Certifies that this is the approved version of the following dissertation: Pursuing Celebrity, Ensuing Masculinity: Morris Ernst, Obscenity, and the Search For Recognition Committee: Mark C. Smith, Supervisor Janet M. Davis Julia Mickenberg Elizabeth Engelhardt Sarah Weddington Pursuing Celebrity, Ensuing Masculinity: Morris Ernst, Obscenity, and the Search For Recognition by Joel Matthew Silverman,...»

«TEXAS ETHICS COMMISSION PERSONAL FINANCIAL STATEMENT FORM PFS INSTRUCTION GUIDE Revised October 20, 2016 Texas Ethics Commission, P.O. Box 12070, Austin, Texas 78711 (512) 463-5800 FAX (512) 463-5777 TDD 1-800-735-2989 Visit us at https://www.ethics.state.tx.us on the Internet. AN EQUAL OPPORTUNITY EMPLOYER The Texas Ethics Commission does not discriminate on the basis of race, color, national origin, sex, religion, age or disability in employment or the provision of services. PERSONAL...»

«SERVICES SIGNING GENERAL INFORMATION & APPLICATION Dear Applicant: Enclosed is a copy of the Massachusetts Department of Transportation – Highway Division (MassDOT – Highway Division) Services Signing General Information and Application. Please refer to the attached list to determine the appropriate District for your facility. Any questions can be directed to the appropriate District Traffic Engineer. The completed application should be returned to the corresponding District Highway...»





 
<<  HOME   |    CONTACTS
2016 www.dissertation.xlibx.info - Dissertations, online materials

Materials of this site are available for review, all rights belong to their respective owners.
If you do not agree with the fact that your material is placed on this site, please, email us, we will within 1-2 business days delete him.