The 7th Annual

NC State University

Undergraduate Summer Research Symposium

 

NSF Alliances for Graduate Education

and the Professoriate (AGEP) SRE

 


Abstracts are listed in alphabetical order by the last name of the corresponding author.

 

 

 

Student Author(s): 

Aponte, Joel

Ballew, Nick

Home Institution:

University of Puerto Rico-Rio Piedras Campus

Program:

NSF Alliances for Graduate Education and the Professiorate (AGEP) SRE

College:

PAMS

Department(s):

Chemistry

Research Mentor(s): 

Elon Ison/Chemistry

Title of Presentation:

Synthesis of Oxorhenium(V) Complexes with Diamido Amine Ancillary Ligands and Their Role in Oxygen Atom Transfer Catalysis

 
 



Oxorhenium(V) complexes have been used for several Oxygen Atom Transfer (OAT) reactions over the last decade. These complexes are effective catalysts for the following OAT reaction between closed shell molecules: XO + Y ---> X + YO. This reaction needs suitable oxygen acceptors (Y’s), such as phosphines, and oxo donors (XO’s), such as pyridine N-oxide (PyO). Although there are diverse studies that involve oxorhenium(V) complexes in OAT reactions, these investigations were limited because the ancillary ligands used did not allow for the study of the effect of substituents on the catalytic activity of these complexes.  Several oxorhenium(V) complexes ReO(RNCH2CH2)2NMeX  (R= Mes, C6F5; X= Me, Cl, I) have been prepared and their reactivity in OAT reactions was studied. Changing the ligand X from a strong donor (e.g. methyl) to a poor donor (e.g. Cl or I) will affect the reactivity dramatically. Varying the R substituent on the diamido amine ancillary ligand will affect the reactivity as well.  Kinetic studies show that ReO(C6F5NCH2CH2)2NMeI has the best catalytic activity in the following OAT reaction: PyO + PPh3 ---> Py + OPPH3.

 

 

 

 

 

Student Author(s): 

Cintron-Maldonado, Jose A.

Home Institution:

University of Puerto Rico-Rio Piedras Campus

Program:

NSF Alliances for Graduate Education and the Professiorate (AGEP) SRE

College:

PAMS

Department(s):

Chemistry

Research Mentor(s): 

Brent Gunnoe/Chemistry

Title of Presentation:

Synthesis of the Catalyst (IPr)Cu(NHPh) and Determination of the Scope and Mechanism of Catalysis

 

 

Aryl amines are an important class of chemical precursors that are used to prepare a variety of materials for pharmaceutical, agricultural and technology industries. With the ultimate goal of providing facile and relatively inexpensive synthetic routes to these high value chemicals, we have designed a copper catalyst that enables coupling of aryl halides and amines.  The monomeric CuI complex (IPr)Cu(NHPh) {IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene} catalyzes the conversion of amines and aryl halides or triflate to aryl amines.  DFT calculations suggest that the reaction proceeds by a CuIII/CuI catalytic cycle in which PhI undergoes oxidative addition to (IPr)Cu(NHPh) to form unobserved (IPr)Cu(NHPh)(Ph)(I).  Studies focused on the scope and mechanism of catalysis will be presented.

 

 

 

 

Student Author(s): 

Díaz-Martínez, Myriam

Cross, Amanda

Shi, Yan

Misra, Shikha

Home Institution:

University of Puerto Rico-Rio Piedras Campus

Program:

NSF Alliances for Graduate Education and the Professiorate (AGEP) SRE

College:

PAMS

Department(s):

Chemistry

Research Mentor(s): 

Alex Nevzorov/Chemistry

Title of Presentation:

Determination of Protein Membranes M2 and E2, Dimyristoylphosphatidylcholine (DMPC) and 1,2-Diheptanoyl-sn-Glycero-3-Phosphocholine (DHPC) Bicelles and Crystal n-Acetyl Leucine by Solid-State NMR

 

 

Solid-State NMR has recently emerged as a powerful tool for structure determination of transmembrane proteins in their native lipid environment. In this study, we focused in obtaining the orientational information of 15N-labeled transmembrane M2 domain of Acetylcholine Receptor, and the E2 domain of Sindbis Virus. The M2 gene was expressed using the cDNA sequence from the Stratagene MegaMan Library and subsequently cloned into the expression vector pET-31b-M2. By contrast, E2 was expressed using the cDNA Toto 1101 clone and then transformed into the pET-31b vector. Both proteins were expressed in E. coli BL21 cells, and purification of recombinant proteins consisted on Ni-NTA affinity column, dialysis with a final step of HPLC. The orientational information will be further obtained using solid-state NMR spectroscopy. In addition, we performed a study of magnetically oriented bicelles, which are formed by a mixture of long-chain/short-chain phospholipids, to better understand their morphology for the subsequent studies of membrane-associated biomolecules. For this work, we employed 31P solid-state NMR of dimyristoylphosphatidylcholine (DMPC) and 1,2-Diheptanoyl-sn-Glycero-3-Phosphocholine (DHPC) bicelles while adding TEMPOL, a soluble stable radical. The results indicated that increasing the concentration of TEMPOL increased 31P-NMR linewidths which can be used in the future to probe the orientation and insertion depth of a protein within the bicelle. We also studied heteronuclear cross-polarization techniques of solid-state NMR which allows one to detect insensitive 15N spins. Cross-polarization transfer was performed to obtain two-dimensional spectra of n-acetyl Leucine molecule in its crystalline form. This study consisted of magnetization transfer from 1H to 15N nuclei allowing the detection of 15N signal and measuring the 1H-15N dipolar couplings. To measure the effect of diverse orientations of the N-H bonds on the NMR spectrum, the crystal was manually rotated, and the peaks in the solid-state NMR spectrum shifted, indicating changes in the local structure.

 

 

 

 

 

Student Author(s): 

Fairey, Donta’ J.

Home Institution:

NCSU

Program:

NSF Alliances for Graduate Education and the Professiorate (AGEP) SRE

College:

Natural Resources

Department(s):

Forestry and Environmental Resources

Research Mentor(s): 

Stacy A. C. Nelson/Forestry and Environmental Resources

Halil I. Cakir/Forestry and Environmental Resources

Title of Presentation:

Use of High-resolution Satellite Imagery for Watershed Land-cover Analysis

 

 

Black Creek is located in Cary, N.C. with headwaters stretching from the downtown area and draining into Lake Crabtree, north of the town.  Black Creek is within a small watershed (850 ha) and is on the EPA 303(d) list for biological impairment due to storm water runoff in an urbanizing environment.  Development activity in the watershed has raised concerns about the water quality of the creek and the surrounding watershed.  To assess the health of the creek and watershed, in an effort to prevent further degradation of the natural resources, accurate land-cover information is critical if reasonable goals for watershed assessment and restoration are to be established.  The objective of this project was to develop highly accurate land cover information of the Black Creek watershed using high-resolution Quickbird (2.44m), remotely sensed imagery.  The watershed area was digitized into 10 land-cover categories and evaluated for classification accuracies.  Our manual classification procedures yielded an overall total accuracy of 85.90% (Kappa 0.8431).  The digitized classification was then compared to an object-extraction approach.  Results from the two approaches provide insight on the feasibility of incorporating high-resolution imagery in small-scale watershed/water quality studies, as well as provide managers with the appropriate information to make effective decisions.

 

 

 

 

Student Author(s): 

Harris, Vanessa A.

Craig, Ashley

Lozada, Fantasy

Home Institution:

California State University, Fullerton

Program:

NSF Alliances for Graduate Education and the Professiorate (AGEP) SRE

College:

CHASS

Department(s):

Psychology

Research Mentor(s): 

Amy Halberstadt/Psychology

Title of Presentation:

Parents’ Socialization Behaviors as Encouraging and Discouraging of Children’s Emotions

 
 

 

The current study examines how parents’ beliefs about emotions are associated with their socialization behaviors in regards to children’s expression of emotions. Parent-child dyads consisting of 9- and 10-year old children and one of their parents (N = 128) filled out questionnaires and participated in a storytelling game with many opportunities to discuss emotion-related memories. Families were African-American, European-American or American Indian Lumbee, and were recruited through collaboration with Virginia Tech University and University of North Carolina - Pembroke.  Parents reported their beliefs about various aspects regarding the value and usefulness of emotion, while their children filled out other questionnaires (Halberstadt et al., 2008). The storytelling game was video recorded and parents’ socialization behaviors, specifically their encouragement and discouragement of children’s emotions were then coded. We predicted that: (1) parents who value emotions will be more likely to prompt responses from children than parents who do not value emotions; (2) parents who value emotions will provide more balanced amounts of encouraging and discouraging compared to those parents who do not value emotions; (3) parents who believe emotions are  informative will be more likely to provide more instances of encouraging and discouraging than parents who believe emotions are not necessarily informative; (4) parents who view emotions as more positive (good, useful, informative) will provide more instances of emotional references than parents who view emotions as negative (bad, useless or dangerous). (5) Parents who believe that emotions are dangerous will be more likely to have greater avoidance or lower encouraging and discouraging scores than parents who do not believe emotions are dangerous. Results from this study will be beneficial to help provide a better understanding about the relationship between parents’ beliefs about emotions and their socialization behaviors towards their children.

 

 

 

Student Author(s): 

Hormenoo, Lydia A.

Home Institution:

Seminole State College

Program:

NSF Alliances for Graduate Education and the Professiorate (AGEP) SRE

College:

CALS

Department(s):

Microbiology

Research Mentor(s): 

Jonathan W. Olson/Microbiology

Title of Presentation:

How Can C. jejuni Be Detected in a Mixed Population Biofilm?

 
 

 

C. jejuni is a gram-negative microaerophilic e-protobacterian.  The primary reservoir of C. Jejuni is the avian species where it is a commensal organism, although human ingestion of C. jejuni leads to campylobacteriosis characterized by bloody diarrhea, fever, and abdominal pain.  Outside of its host, it is imperative for this microorganism to acclimatize itself to its environment.  Formerly, it was believed that C. jejuni survived poorly outside of its host.  Recently however, studies have shown that C. jejuni can indeed survive in the environment via biofilm formation. In order to detect the activities of C. jejuni outside of its host, we have implemented a reporter system by transforming this organism with a GFP (Green Fluorescent Protein) gene encoding plasmid pMEK91.  These strains fluoresce under ultra violet light, and hence can be detected in the external environment.  Currently, we are in the process of testing this strain for the formation of biofilms outside its ecological niche.

 

 

 

 

 

Student Author(s): 

James, Natasha

Home Institution:

University of Georgia

Program:

NSF Alliances for Graduate Education and the Professiorate (AGEP) SRE

College:

Natural Resources

Department(s):

Forestry and Environmental Resources

Research Mentor(s): 

Robert C. Abt/Forestry and Environmental Resources

Title of Presentation:

Renewable vs. Sustainable: Woody Biomass in the State of Georgia

 

 

As fossil fuels become more expensive and detrimental to the environment, there is now a growing need to find and utilize alternative and renewable energy sources. The state of Georgia has recognized this need and has proposed a Renewable Portfolio Standard that will mandate a certain percent of total electricity generated be from renewable sources. With an estimated 5.31 million dry short tons of logging residuals available in the state, there has been a push to use this woody biomass to create energy. Like the recent experience in corn, demand for the resource from both traditional and energy uses may lead to significant market impacts. In addition, increased harvest levels will change the age distribution of the forest and affect future wood availability. This study was conducted to compare the level of energy that can be sustainably derived from woody biomass and Georgia’s energy demand; as well as determine how the changes in timber use will affect market prices. Two dimensions of sustainability are examined. The first dimension explores whether the increased demand is likely to raise removals higher than growth and decrease the physical stock of inventory over time. The second dimension investigates economic sustainability by examining the projected impact on real price trends. We hypothesize that as the demand for energy increases, the demand for woody biomass derived from logging residuals will increase as well, causing energy producers to begin utilizing other woody sources, such as roundwood.  This may cause competition in the wood market, increasing the price of timber.  Higher wood prices may reduce its economic viability as an alternative energy source.  Data was collected to generate Georgia’s demand for energy through 2030. Using the Subregional Timber Supply Model, the harvest and inventory levels required to meet demand and the effect on market prices were estimated.

 

 

 

 

 

Student Author(s): 

Jean-Baptiste, Nazaire

Home Institution:

Saint Augustine's College

Program:

NSF Alliances for Graduate Education and the Professiorate (AGEP) SRE

College:

Veterinary Medicine

Department(s):

Oncology

Research Mentor(s): 

Marlene Hauck/Veterinary Medicine

Title of Presentation:

Gene Expression in Feline Soft Tissue Sarcomas

 

 

Introduction: Injection-site sarcomas are a type of tumor that arise from the connective tissues of cats. Cats may develop the tumors at the site at which they have been previously vaccinated. Like most cancers, these tumors will ultimately kill the patient. Even with the best treatment, more than 50% of patients eventually die. This work was conducted to validate previously collected gene expression data from injection site sarcomas in cats. The data is being validated to confirm that the information gathered using cat tissues on a  human microarray is correct. Evaluating the differences in gene expression between the tumors and normal feline tissues will increase understanding of why these tumors develop and aid in the improvement of tumor treatment and prevention. Methods: Before beginning the experiment, optimization of the qualitative reverse transcriptase-PCR SYBR greener protocol was performed on RNA was extracted from a feline lymph nodes using RNeasy mini kit (Qiagen). The quality and quantity of the RNA were evaluated using the nanodrop and gel electrophoresis. Using the gene expression data previously generated from injection site sarcomas and normal tissue, four genes that were selected to validated: Protein Tryosine Phosphatase Receptor Type G (PTPRG), Adenosine Deaminase (ADA), Annexin A3 (ANXA3), and Protocadherin (PCDH21). Relative gene expression levels were determined using qRT-PCR. Determination of the level of gene expression was calculated by evaluating threshold values. Results: Optimization of the qRT-PCR protocol is ongoing. Given the limited amount of RNA available from the feline tumors, no samples will be evaluated until the protocol is reliable. Conclusions: Validation of gene expression data is necessary to determine the accuracy of the information, particularly when using a cross-species array (cat on human). This work will help determine the usefulness of the human array for the interrogation of feline tissues.

 

 

 

 

 

Student Author(s): 

Meheux, Carlos J.

Bihlmeyer, Nathan

Home Institution:

University of Maryland Baltimore County

Program:

NSF Alliances for Graduate Education and the Professiorate (AGEP) SRE

College:

CALS

Department(s):

Genetics

Research Mentor(s): 

Robert G. Franks/Genetics

Title of Presentation:

Transcriptional Co-Repressor Protein-Protein Interactions between LEUNIG, SEUSS, and SEUSS-LIKE, in Arabidopsis thaliana

 
 

 

Transcription repressors play important roles in preventing crucial regulatory proteins from being inappropriately expressed. LEUNIG (LUG) and SEUSS (SEU) normally act to prevent ectopic expression of the floral homeotic gene AGAMOUS (AG) in the flowers of Arabidopsis thaliana. AG is known to be responsible for organ identity specification in Arabidopsis flowers. However, it is known that the N-terminal LUFS domain of LUG is required for transcription repression and for direct interaction with SEU. Furthermore, it has also been proven that LUG and SEU form an evolutionary conserved co-repressor complex in plants, analogous to yeast Tup1-Ssn6 complex. Some other proteins that share sequence similarity to SEUSS, also known as SEUSS-LIKE (SLK), have also been identified in Arabidopsis. Genetic experiments have indicated that SEU and SLK share functional similarity, but there is no biochemical evidence that SLK interact with LUG the same way SEU does. To test the claims made about the possible interactions between these two sets of proteins, optimal conditions for the expression of soluble fusion proteins from SEU, SLK, and interacting LUG proteins were determined. Different solubilization and renaturation conditions were tried, including the use of detergents. Next, conditions were tested for the in vitro interactions between SEU and LUG. Finally, tests for novel interactions between SEU, SLK and LUG were conducted. These protein-protein interactions were conducted on both Amylose and Glutathione resins. SEU coding sequence was fused to Glutathione-s-transferase (GST), while the LUG coding sequence was fused to Maltose binding proteins (MBP). A western blot that contained antibodies selective for the SEU, SLK and LUG proteins will be used to verify the identity of the interacting proteins.

 

 

 

 

 

Student Author(s): 

Mendez, Veronica R.

McGinnis, Jennifer Lindberg

Home Institution:

California State University, Northridge

Program:

NSF Alliances for Graduate Education and the Professiorate (AGEP) SRE

College:

CHASS

Department(s):

Psychology

Research Mentor(s): 

S. Bartholomew Craig/Psychology

Title of Presentation:

Leaders Behaving Badly: Abusive Behaviors and Their Consequences

 
 

 

Recently, the leadership field has turned its attention to leader behaviors that contribute to a supervisor’s ineffectiveness. One such construct is abusive supervision, or “subordinates’ perceptions of the extent to which supervisors engage in the sustained display of hostile verbal and nonverbal behaviors, excluding physical contact” (Tepper, 2000, p. 178). Although research on abusive supervision is still in its infancy, preliminary findings suggest that employees working under abusive leaders may experience poor quality of work life and well-being (Tepper, 2007). Hence, abusive supervisory behaviors can have a profound negative impact on employees as well as the organizations that employ them. The purpose of the current study is to understand the abusive behaviors in which leaders engage, as well as some of the consequences of these behaviors. An archival dataset of 120 managers was used in this study; all managers participated in a five-day leadership development program. A customized 360-degree feedback instrument asking for examples of “bad leadership (or bad interpersonal skills)” was administered to the managers as well as their coworkers, customers, vendors, and shareholders. Responses to this instrument were used as the measure of abusive supervisory behavior in the current study. A preliminary content analysis of 20 managers (approximately 80 coworkers) revealed responses that have been classified into 31 behavioral categories. These results suggest that the most commonly named examples (identified in 65% of cases) fall within a category termed “Displaying a Negative Attitude.” This includes outward expressions of frustration with coworkers and/or the organization. The second most common behavior (60% of cases) is “Insensitivity,” which includes a lack of regard for the feelings of coworkers. The third most common set of behaviors (30% of cases) was categorized as “Incivility, Personal Attacks, and Sarcasm.” Implications of these findings for employees and organizations will be discussed.

 

 

 

 

Student Author(s): 

Moody, LaTisha V.

Home Institution:

North Carolina A&T State University

Program:

NSF Alliances for Graduate Education and the Professiorate (AGEP) SRE

College:

Veterinary Medicine

Department(s):

 

Research Mentor(s): 

 

Title of Presentation:

My Experience at NC State CVM and the USDA

 

 

This summer, I had the opportunity to participate in the CVM-USDA internship program.  It is a ten program specifically targeted for undergraduates who are interested in public health and veterinarian careers.  The first 6 weeks were spent at North Carolina State in Raleigh, Durham working at the College of Veterinary Medicine’s research laboratory and participating in the daily clinical rounds at the animal hospital.  The last 4 weeks, I worked in the various laboratories and agencies within the USDA such as National Veterinary Services Laboratories located in Ames, Iowa.

 

 

 

Student Author(s): 

Muniz, Marc N.

Schmidt, Robert D.

Home Institution:

Montclair State University

Program:

NSF Alliances for Graduate Education and the Professiorate (AGEP) SRE

College:

PAMS

Department(s):

Chemistry

Research Mentor(s): 

David A. Shultz/Chemistry

Title of Presentation:

A New "Spin" on Molecular Switches

 
 


The iron complex (NN-Cat)FeIIITpCum, Me, where NN= nitronylnitroxide, Cat= catecholate, and Tp = hydro-tris(3-methyl-5-cumenylpyrazolyl) borate, is synthesized and utilized to investigate the Light Induced Excited Spin State Trapping (LIESST) phenomenon.  Upon irradiation with intense visible light in a Superconducting QUantum Interference Device (SQUID) magnetometer, charge transfer from the NN-Cat ligand to the metal should be induced thus reducing FeIII to FeII as follows:

(NN-Cat)FeIIITpCum, Me  → (NN-SQ)FeIITpCum, Me
Where SQ= semiquinone


In doing so, a spin state transition occurs thus rendering the system bistable across a certain temperature range, the magnitude of which varies depending upon the compound.  This imitates the type of true/false switch that serves as the backbone to all digital electronic devices, suggesting that this effect may be applicable to nanoscale electronic technology. Synthesis of the complex was carried out according to previously effective techniques and compounds were characterized by 1H-NMR (proton nuclear magnetic resonance), IR (infrared), EPR (electron paramagnetic resonance), and UV-VIS (ultra-violet visible) spectroscopy.   

 

 

 

Student Author(s): 

Reynolds, Alexander E.

Home Institution:

Cornell University

Program:

NSF Alliances for Graduate Education and the Professiorate (AGEP) SRE

College:

Veterinary Medicine

Department(s):

Clinical Sciences

Research Mentor(s): 

Christopher L. Mariani/Clinical Sciences

Title of Presentation:

Immunophenotyping of Lymphocytes in Canine Granulomatous Meningoencephalitis

 

Granulomatous meningoencephalitis (GME) is an inflammatory central nervous system (CNS) disease of unknown etiology.  It is characterized by accumulations of macrophages and lymphocytes around CNS blood vessels.  Only a small number of studies have attempted to characterize these perivascular cuffs, showing T cells to be the majority of lymphocytes present.  Other investigators have suggested that GME is a form of B cell lymphoma.  Preliminary work at our institution showed a large number of B cells in inflammatory brain samples, and we were interested in examining a larger number of GME cases with several different inflammatory cell markers in order to confirm these trends, further characterize the cellular immune response, and resolve discrepancies found in earlier studies. Tissue sections were obtained from formalin-fixed, paraffin-embedded brains of GME diagnosed dogs.  After antigen retrieval, the sections were stained with antibodies for CD3 (T cells), CD79α (B cells), CD45RA (naïve lymphocytes and NK cells), CD18 (microglia and macrophages), CD11d (macrophages and dendritic cells), and MHCII (antigen-presenting cells), counterstained with hematoxylin, and visualized using a peroxidase dependent detection system.  For T and B cell analysis, perivascular cuffs were identified and a minimum of 500 cells counted with positively labeled cells expressed as percentages of total inflammatory cells.  A greater percentage of B cells was found in most cases (mean 30%, range 0-77%), while T cells were found less frequently (mean 14%, range 0-49%).  We also noted robust infiltration of CD18 positive cells and lesser numbers of CD11d positive cells.  Enumeration of these cell populations and evaluation of the other immunostained sections is underway. In addition, to ascertain whether GME is a form of B cell lymphoma, laser capture microscopy with subsequent polymerase chain reaction for antigen receptor rearrangement is planned.  This will allow clonal analysis of lymphocytes, to distinguish inflammatory cell populations from neoplastic tissue.

 

 

 

Student Author(s): 

Rivera Serrano, Efraín E.

Ananthakrishnan, Sudha

Home Institution:

Pontifical Catholic University of Puerto Rico

NCSU

Program:

NSF Alliances for Graduate Education and the Professiorate (AGEP) SRE

College:

CALS

Department(s):

Microbiology

Research Mentor(s): 

José Bruno-Bárcena/Microbiology; Biomanufacturing Training and Education Center (BTEC)

Title of Presentation:

Cloning of the β-Galactosidase-like gene (bgIA) from Sporobolomyces singularis into Escherichia coli and Pichia pastoris

 
 

 

Galacto-oligosaccharides (GalOS) selectively stimulate probiotic microflora including microbiota constituent of the gastrointestinal microbiome. One group of microorganisms able to consume GalOS is the Bifidobacteria spp. This ability is usually linked to the presence of galactosidases that allow cells to specifically hydrolyze β(1-4) sugar bonds. This group of enzymes has also been shown to catalyze the synthesis of GalOS, which subsequently can be utilized to efficiently produce GalOS. Recently, a β-galactosidase-like enzyme from a strain of Sporobolomyces singularist was characterized and the sequenced [6]. This strain differed from its parent strain, revealing a 10-fold increase in its β-galactosidase-like (BglA) activity. Herein, the β-galactosidase-like ORF (bglA) was subjected to codon optimization and synthesized. Consequently, to facilitate its expression and the cloning steps in bacterial hosts, the internal ORF restriction sites were eliminated, the GC content was adjusted, and a 5’XhoI and a 3’NotI site were added to the synthetic ORF.  The ORF was then inserted into the cloning (pUC57), expression (pGS21a and pET24d), and integrative (pPIC9) vectors, thus yielding pUC57::bglA, pGS21a::bglA, pET24d::bgIA, and pPIC9::bgIA, respectively.  As an example, pPIC9::bgIA was completed after the bglA from pUC57::bglA was religated into the pPIC9 multicloning site (a Pichia pastoris integrative vector) and transformed into E. coli XLB-1. All of the new vectors were sequenced to confirm the correct in-frame insertions. E. coli BLR (DE3), a lacZ- strain, was chosen as a host and the plasmid bearing cells were subjected to gene induction with 5mM IPTG.  The cell free extract content was subsequently separated on SDS-PAGE gels and visualized using coomassie blue.

 

 

 

 

Student Author(s): 

Roque-Peña, Joan E.

Bromfield-Lee, Deborah C.

Home Institution:

University of Puerto Rico at Cayey

Program:

NSF Alliances for Graduate Education and the Professiorate (AGEP) SRE

College:

PAMS

Department(s):

Chemistry

Research Mentor(s): 

Maria T. Oliver-Hoyo/Chemistry

Title of Presentation:

Olfactory Titrations Using Glucosinolates Extracted from Rutabaga

 
 

 

Rutabaga is a root vegetable of great consumption in North America. It contains glucosinolates which when hydrolyzed are converted to three products; isothiocyanates, nitriles, and thiocyanates. The isothiocyanates are responsible for the peculiar smell of the vegetable. We are investigating the ability of the rutabaga to serve as an olfactory indicator for titrations in which colorimetric indicators are normally used. The main objective is to find the best method of extraction of the glucosinolates in order to use them effectively as an olfactory indicator. In order to fulfill our research objectives, extractions of the rutabaga were performed using a soxhlet apparatus with various heating processes of the vegetable; rutabaga in water bath, partially oven-dried, and fully oven-dried. The samples were then rotoevaporated or distilled using fractional distillation. The various fractions obtained were tested as olfactory indicators. The most accurate results were obtained using the fraction with a 100°C boiling point (rutabaga in water bath). However, this fraction has a limited lifespan of approximately two weeks. The 80°C boiling point fraction (partially oven-dried) gave comparable results to the one obtained at 100°C without undergoing decomposition  and remaining a viable olfactory indicator after one-month of extraction.

 

 

 

 

Student Author(s): 

Santiago, Koraliz

Home Institution:

University of Puerto Rico at Cayey

Program:

NSF Alliances for Graduate Education and the Professiorate (AGEP) SRE

College:

PAMS

Department(s):

Chemistry

Research Mentor(s): 

Jonathan S. Lindsey/Organic Chemistry

Marcin Ptaszek/Organic Chemistry

Title of Presentation:

Synthesis of a Simple Model for Bacteriochlorophyll c

 

 

Bacteriochlorophyll c is the main light-harvesting pigment in green photosynthetic bacteria. Bacteriochlorophyll c self-assembles in chlorosomes in the absence of protein scaffolding. The core structure of this pigment is the chlorin macrocycle which is characterized by two saturated carbons at the 17- and 18-positions of the ring. The objective of this project is to synthesize a chlorin derivative with substituents that allow the study of analogous self-assembly processes. The synthesis relies on the joining of a Western half and an Eastern half.  The Western half was synthesized via Michael addition, reductive cyclization, and palladium coupling to afford 1,1,3-trimethyl-8-vinyltetrahydrodipyrrin. Bromination of 1-formyldipyrromethane provided the known Eastern Half 1-formyl-8.9-dibromodypyrromethane needed for the chlorin synthesis.  An alternative synthetic route was studied beginning with the iodination of pyrrole-2-carboxaldehyde, to obtain the respective iodotetrahydrodipyrrin Western Half. Both Western halves are new compounds, the availability of which should enable a concise entrée to bacteriochlorophyll c analogues.

 

 

 

 

Student Author(s): 

Slocum, Jamar A.

Home Institution:

Winston Salem State University

Program:

NSF Alliances for Graduate Education and the Professiorate (AGEP) SRE

College:

Engineering and Technology

Department(s):

Biomedical Engineering

Research Mentor(s): 

Peter L. Mente/Biomedical Engineering

Title of Presentation:

The Mechanical Causes of Early Chondrocyte and Cartilage Matrix Changes that Lead to Later Degeneration

 
 

 

Purpose:  Osteoarthritis is a degenerative disease of the articular joints that involves the breakdown and eventual loss of cartilage resulting in pain from bone on bone contact. We are interested in developing an impact injury model to understand the mechanical causes of early chondrocyte and cartilage matrix changes that lead to later degeneration.  The research project’s ultimate goal is to examine differences in chondrocyte gene expression and matrix damage following different types of applied mechanical injury to the articular cartilage.  Finite element analysis will be used to model in vitro impactions on porcine patella to allow the observed damage to be correlated to mechanical parameters such as stress and strains. We will be using pressure sensitive film to measure contact pressures between the cartilage and impactor which will allow us to validate the predicted stresses from the finite element model. Hypothesis: Shear stress will produce greater damage to the cartilage matrix and will result in a larger production of enzymes involved in extracellular matrix degeneration.   Methods: We obtained porcine knee joints from a local slaughterhouse and only cartilage tissue with no existing damage is used.  Three different types of loading conditions have been examined- an axial impaction, a shear impaction, and a non- impacted control.  The axial impactions were carried out using a hydraulic load frame at a loading rate of 25 mm/sec to a peak load level of 2000 N. For shear impactions, the cartilage surface is loaded axially to 500 N then translated 5 cm to induce tangential loading. Following impactions, patellae will be kept in culture for 0, 3, 7 or 14 days. Media was changed daily.  Finite element analysis will be used to determine the various stresses and strains chondroctyes experience within the underlying cartilage tissue. Pressure film will provide a way to measure experimental pressures to validate our model. We placed high pressure film between the cartilage and impactor during an in-vitro axial impaction. Within the pressure film, are microcapsules, which are discharged in response to the different degrees of pressure.  The computer software, Metamorph® was used to calculate the pixel intensity from the pressure film. Pressure values were determined from correlating intensity values from the pressure film and a calibration chart. 

 

 

 

 

Student Author(s): 

Sosa, Jason O.

Home Institution:

University of Puerto Rico-Rio Piedras Campus

Program:

NSF Alliances for Graduate Education and the Professiorate (AGEP) SRE

College:

PAMS

Department(s):

Chemistry

Research Mentor(s): 

Maxim A. Voynov/Chemistry

Tatyana I. Smirnova/Chemistry

Alex I. Smirnov/Chemistry

Title of Presentation:

Hydroxyl Radicals’ Production as a Possible Mechanism of Fe2O3 Nanoparticles Toxicity in Biological Systems

 
 

 

Spin trapping is the primary experimental method for identifying reactive free radicals in biological systems.  The method is based on introducing a spin trap – a diamagnetic molecule that is capable of readily reacting with short-lived radicals forming more stable radical spin adducts that are then characterized by Electron Paramagnetic Resonance (EPR) spectroscopy.  Magnetic nanoparticles such as Fe2O3, have been known to display a rather high toxicity in living organisms.  However, the underlying toxicity mechanism remains a mystery.  We hypothesize that Fe2O3 nanoparticles could act as Fenton reaction promoters generating hydroxyl radicals (OH●) through H2O2 decomposition.  Hydroxyl radicals are the most harmful oxidizing species that are capable of seriously damaging virtually any of the cell components: carbohydrates, nucleic acids, lipids, and proteins.  To ascertain whether hydroxyl radicals are generated from H2O2  in the presence of Fe2O3 nanoparticles we have employed a spin trap DMPO (5,5-dimethyl-1-pyrroline-N-oxide).  Indeed, an incubation of Fe2O3 nanoparticles with just H2O2 and DMPO produced a weak but characteristic EPR spectrum corresponding to the DMPO-OH● adduct. A much stronger EPR signal of DMPO-OH● adduct was observed in the superoxide–driven Fenton reaction, which takes place in biological systems.  We speculate that superoxide radicals reduce Fe3+ on the surface of the Fe2O3 nanoparticles to Fe2+, thus, promoting H2O2 decomposition.  The low concentration of DMPO-OH● adduct observed in the absence of O2- may arise from H2O2 decomposition by traces of Fe2+ at the surface of the Fe2O3 nanoparticles.  To conclude, we have shown that toxicity of the Fe2O3 nanoparticles could be related to a superoxide-promoted formation of Fe2+ on the particle, thus, causing production of OH● that is damaging to living cells.  We believe that this is the first experimental evidence that generation of hydroxyl radicals in biological systems could be promoted by Fe2O3 nanoparticles.

 

 

 

Student Author(s): 

Speller, Lassiter F.

Home Institution:

Winston-Salem State University

Program:

NSF Alliances for Graduate Education and the Professiorate (AGEP) SRE

College:

CHASS

Department(s):

Psychology

Research Mentor(s): 

Christopher B. Mayhorn/Human Factors & Ergonomics

Title of Presentation:

w8, wats that face 4?: Emoticon Comprehension

 
 

 

Ninety-four percent of American teenagers go online to access the internet or email, and 85% of teenagers engage in some form of electronic communication (Pew, 2008). Computer mediated communication is an effective way to contact people asynchronously or synchronously. Instant messenger systems are a popular venue through which people primarily communicate synchronously. Having emoticons available adds an emotional aspect to the primarily text-based mode of communication, increasing social presence that in turn improves message comprehension. In the present research, 32 participants completed a comprehensive survey designed to evaluate their familiarity and experience with instant messaging software applications.  Participants were also asked to view and interpret the meaning of 58 separate emoticons. Once the correctness of these qualitative responses regarding emoticon comprehension was assessed, results indicated that the range in variance of comprehension was high across emoticons. The ten emoticons with the highest and lowest comprehension scores were determined.  Frequency of use and correct usage were also assessed. Theoretical application and future research are discussed.

 

 

 

 

 

Student Author(s): 

Torres-Kolbus, Jessica

Young, Douglas D.

Home Institution:

University of Puerto Rico at Cayey

Program:

NSF Alliances for Graduate Education and the Professiorate (AGEP) SRE

College:

PAMS

Department(s):

Chemistry

Research Mentor(s): 

Alexander Deiters/Chemistry

Title of Presentation:

Rapid Microwave-assisted Synthesis of Non-natural Amino Acids

 
 

 

Recently, several new technologies have been developed to incorporate non-natural amino acids into peptides and proteins. These afford the introduction of novel functional groups into proteins expanding the chemical and biological diversity of these biomacromolecules. Thus, a high demand of new methodologies to access non-natural amino acids exists. Our goal is to investigate the use of microwave irradiation to rapidly synthesize amino acid derivates. This approach is viable as microwave irradiation has previously been found to increase reaction rates, and at the same time increase the reaction yields of several organic reactions. For this purpose, a method was developed to alkylate amino acid precursors in 10 to 20 minutes; followed by a second microwave irradiation to deprotect and decarboxylate the molecule, yielding the non-natural amino acid. Using this technology, seven amino acids have been prepared with yields from 65 to 80% in approximately 3 hours per compound. With this approach, libraries of amino acid analogs can be rapidly prepared for future biological and chemical developments of proteins.

 

 

 

Student Author(s): 

Trinidad, Anna M.

Home Institution:

California State University Fullerton

Program:

NSF Alliances for Graduate Education and the Professiorate (AGEP) SRE

College:

CALS

Department(s):

Molecular and Structural Biochemistry

Research Mentor(s): 

Greg Buhrman/Molecular and Structural Biochemistry

Carla Mattos/Molecular and Structural Biochemistry

Title of Presentation:

Determining the Structure-Function of Q61T Ras Point Mutant

 
 

 

The Ras family of proteins are small, monomeric, GTPase proteins involved in numerous cell signaling pathways involved in control of cell growth, proliferation, differentiation, and apoptosis. With a known involvement in 30% of all human tumors, mutant Ras proteins are highly oncogenic. Important residues responsible for increasing transformation efficiencies when a point mutation is acquired are glycine 12 and glutamine 61 (Gln61). Gln61 is a catalytic residue which functions to stabilize the transition state of Ras during GTP hydrolysis. Rap, a cytosolic homolog of Ras, has a characteristic threonine located on residue 61, which is required for binding GTP, rather than for catalysis. In order to investigate the role this residue plays in structural differences between Ras and Rap, we used site-directed mutagenesis to create a Q61T Ras point mutant. After engineering this mutation, the mutant protein was grown in E. coli, purified and crystallized. The structure and function of Ras Q61T will provide insight into the significance of glutamine within the Ras family and the distinctive nucleotide binding features of Rap.

 

 

 

 

Student Author(s): 

Tsuen, Ho Yan

Ross, Sarah G.

Home Institution:

NCSU

Program:

NSF Alliances for Graduate Education and the Professiorate (AGEP) SRE

College:

CHASS

Department(s):

Psychology

Research Mentor(s): 

John C. Begeny/Psychology

Title of Presentation:

An Examination of Vocabulary Instruction within a Reading Fluency Intervention

 
 

 

In the United States, Spanish is the language spoken by the largest population of English Language Learners (ELLs). In 2007, national statistics indicate that only 17% of fourth grade Hispanic students were reading at or above a proficient level (i.e. the ability to demonstrate an overall understanding of the text, providing inferential as well as literal information). In contrast, 42.67% of their fourth grade Caucasian peers were reading at a proficient level.  Using a single-subject alternating-treatments design with four Hispanic ELL participants, this study investigated the relative efficacy of a brief vocabulary intervention and a brief reading fluency intervention, both of which were compared to a non-intervention control condition. Students’ vocabulary development and oral reading fluency were measured following exposure to the alternating conditions.  Results indicated that the fluency intervention improved students’ reading fluency better than the control and vocabulary intervention conditions, but the vocabulary condition was no more effective than the control condition. In terms of students’ vocabulary development, neither the fluency nor vocabulary interventions were consistently more effective than the control condition, with the exception of one student who benefited from the vocabulary intervention. Findings suggest that elementary-aged ELLs with limited vocabularies may require intervention of considerably greater intensity than those provided in this study.

 

 

 

 

Student Author(s): 

Tucker, LaTonya S.

Home Institution:

NCSU

Program:

NSF Alliances for Graduate Education and the Professiorate (AGEP) SRE

College:

CHASS

Department(s):

Psychology

Research Mentor(s): 

Pamela Martin/Psychology

Title of Presentation:

The Effects of Racial Identity on GPA

 

 

As time passes, African Americans mature in their racial identity. Racial identity is a developmental process that becomes apparent in the way someone views their race based on personal and societal experiences (Worrell, Vandiver, Cross, 2004). Racial identity has been linked to several different outcomes in young adults to include academic performance. Researchers have documented that university settings might shape racial identity attitudes of students (Sellers et al, 1997 and 1998).  Also, recent research on African American college students discusses the effects of racial identity on academic achievement (Harper & Tuckman, 2006). Thus, this study will investigate gender differences among African American students that attend a historically black university.  This investigation will also assess the relationship between racial identity and academic performance.  The Cross Racial Identity Scale (CRIS) which utilizes Nigrescence theory to examine social memberships, personality traits, and psychological functioning among African Americans will be used (Worrell, et. al, 2004).  Implications and future directions will be discussed.

 

 

 

 

Student Author(s): 

Vélez, Natalia

Home Institution:

University of Puerto Rico-Rio Piedras Campus

Program:

NSF Alliances for Graduate Education and the Professiorate (AGEP) SRE

College:

CALS

Department(s):

Genetics

Research Mentor(s): 

Jose Alonso/Genetics

Anna Stepanova/Genetics

Title of Presentation:

Characterization and Mapping of an Arabidopsis ethylene and Sugar Hypersensitive Mutant

 

 

Plant survival relies on their ability to adapt or adjust their growth and development in accordance with the constantly changing environmental conditions. These “tuning” is dependent not only on the capacity of plants to sense changes in their surroundings, but also on their ability to integrate multiple signals to produce specific responses. To better understand this signal integration process at the molecular level, a genetic approach was taken. An Arabidopsis mutant that displays hypersensitivity to two critical plant growth regulators, the hormone ethylene [that mediates many plant stress responses] and sugar (glucose and sucrose) [that provides critical cues on the metabolic status of the plant], has been isolated. In this study, we have characterized this mutant phenotypically and PCR-mapped it to a small region on the bottom of chromosome 5. A candidate-based approach is being employed to identify the gene responsible for the sugar/ethylene hypersensitivity. Once the molecular nature of the mutation(s) is determined, experimental strategies will be designed to investigate the potential role of the corresponding gene(s) in integrating metabolic and stress signals mediated by ethylene in plants.

 

 

 

Student Author(s): 

Verba, Kliment A.

Home Institution:

The College of New Jersey

Program:

NSF Alliances for Graduate Education and the Professiorate (AGEP) SRE

College:

CALS

Department(s):

Biochemistry

Research Mentor(s): 

Carla Mattos/Biochemistry

Title of Presentation:

An Investigation of Regulation of BAF through MSCS of BAF and Solution of the Structure of BAF-L, a Potential Regulator Protein

 
 

 

BAF(Barrier to Autointegration Factor) is a cellular protein with crucial roles in nuclear assembly, chromatin organization and other cellular functions. However, how BAF is regulated, and a number of  BAF’s potential partners, are still unknown. BAF-L (BAF-Like) is a novel protein which is 40% identical to BAF. The current model is that BAF-L functions in the regulation of BAF by heterodimerization. BAF-L is only known to bind itself, BAF, and weakly to LEM (LAP2, emerin, MAN1) domain proteins. By heterodimerizing with BAF, BAF-L may reduce BAF’s binding affinity to DNA. However, the sites at which this interaction occurs and the overall structure of BAF-L are still unknown. In this project we aspired to shed light on BAF’s regulation. First, we crystallized BAF and used the MSCS (Multiple Solvent Crystal Structures) method to map potential active sites. However, the resolution of the resulting crystals was too low for MSCS method to be applied. Next we purified BAF-L in pure enough form for crystallization, and attempted to find crystallization conditions and solve the structure of BAF-L. Hopefully, this data will elucidate structural factors that function in BAF regulation. 

 

 

 

 

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