22nd Hayes Graduate Research Forum (April, 2008)

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https://kb.osu.edu/handle/1811/31865

The Arts
1st place: Fischer, Julia
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2nd place: East, Alicia
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3rd place: Wills, Carrie
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Biological Sciences
1st place: Rottinghaus, Erin
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2nd place: Nair, Manoj S.
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3rd place: McMichael, Brooke

Business
1st place: Byron, Reginald
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2nd place: Singh, Suresh
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3rd place: Russell, Eric
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Education
1st place: Cannon, Elizabeth A.
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2nd place: Silverman, Sarah Kozel
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3rd place: Yough, Michael
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Engineering
1st place: Kamarajugadda, Sai
2nd place: Ahmadkhanlou, Farzad
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3rd place: Ellis, Jeffrey
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FAES and Human Ecology
1st place: Shustack, Daniel
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2nd place: Hauver, Stephanie
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3rd place: Subramanian, Anand
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Humanities
1st place: Sturkey, William
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2nd place: Smith, Sarah
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3rd place: Hinshaw, Wendy
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Math and Physical Sciences
1st place: Schumacher, William
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2nd place: Lee, Donghun
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3rd place: Middleton, Chris
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Poster
1st place: Farmer, Cristan
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2nd place: Crawford, Robert
3rd place: Blatt, Samantha
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Professional Biological Sciences
1st place: Roberts, Ryan
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2nd place: Monasky, Michelle
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3rd place: Eiring, Anna M.
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Social and Behavioral Sciences
1st place: Klaus, Haagen
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2nd place: Brothers, Brittany M.
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3rd place: Painter, Matthew II.
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Care and Sexuality in Disabled/Nondisabled Intimate Relationships
(2008-04) Smith, Sarah; Burack, Cynthia
In contemporary feminist research, the applied fields (e.g., rehabilitation and counseling), popular culture and the disability rights movement, “care” in nondisabled/disabled intimate relationships is often represented as a binary between care-givers and care-receivers. In other words, the disabled partner is represented as only a care-receiver and the nondisabled partner as only a care-giver. This dependency dynamic desexualizes nondisabled/disabled relationships and perpetuates stereotypes about disability and what it means to provide care. By turning to self-representations of people in disabled/nondisabled relationships, this project illuminates alternative understandings of care and sexuality. The author combines data from 1) focus groups conducted by the author, 2) disability autobiography, and 3) documentary films for a triangulated research methodology that seeks multiple meanings of care and sexuality in nondisabled/disabled relationships. Contrary to dominant representations of care in disabled/nondisabled relationships, the author finds that the boundary between caregiver and care-receiver is often blurred. That is, the disabled partner gives care and the nondisabled partner receives care and vise versa. The care relationship is characterized by reciprocity for these couples, echoing the philosophy of early feminist care ethicists like Nel Noddings. In addition, physical care is often part of sexual intimacy. Bathing, dressing, feeding and other personal care activities are eroticized, adding to the couples’ overall sexuality. In fact, many couples believe such a heightened level of intimacy makes them closer than couples without physical disability. This finding suggests disabled/nondisabled couples practice a non-normative sexuality that is often overlooked or dismissed. In sum, self-representations contradict the binary and asexual relationship between disabled and nondisabled partners popularized in academic research and mainstream media. Disabled/nondisabled couples emphasize reciprocity, mutuality, and eroticized daily care in their relationships. These findings help correct popular stereotypes and suggest that reciprocal relationships and alternative forms of sexuality should be considered in future research on care and disability.
Reproductive phenology of the Acadian flycatcher (Empidonax virescens), a Neotropical migratory bird species, across an urban to rural gradient in central Ohio, USA
(2008-04) Shustack, Daniel; Rodewald, Amanda
The tendency for birds to reproduce earlier in the season has been observed in urban compared to rural populations, but these observations are limited primarily to species that spend all or most of the year in North America (i.e., resident or short-distance migrants). However, the factors that influence the reproductive timing of resident and short-distance migrants are unlikely to have the same influence on Neotropical migrants, a group of birds requiring conservation action due to long-term population declines. To understand the relationship between urbanization and reproductive phenology or timing of a Neotropical migratory bird species I (1) described the pattern of reproductive phenology in Neotropical migratory bird species across an urban to rural gradient, (2) assessed the reproductive consequences of varied breeding phenology, and (3) evaluated the extent to which alternative factors might explain differences in reproductive phenology. Data were collected between 2001 and 2007 on 35 different forests spanning an urban to rural gradient in central Ohio, USA. I used Acadian flycatchers (Empidonax virescens) as a model species. Birds were captured, marked, measured, released, and monitored throughout the breeding seasons. The general pattern of breeding phenology was opposite that found in most resident and short-distance migrant birds. Birds arrived later, initiated clutches later, and finished nesting earlier than birds breeding in more urban forests. The combination of delayed clutch initiation and earlier completion of nesting activity resulted in an abbreviated nesting season associated with urbanization. Ultimately, this attenuated nesting season reduced the number of nests attempted and young produced by urban-breeding birds and shifted the timing of fledging, with the first fledglings being produced relatively later in the breeding season. The underlying causes of the phenological differences are less clear. One possibility supported by my data is that urban forests were disproportionately settled by small females, which initiated their first clutches later in the nesting season than larger females. This study provides the first evidence that urbanization is associated with attenuated nesting seasons for Neotropical migratory birds and that this shift in breeding phenology may have reproductive consequences.
Excited-State Dynamics of Pyrimidine DNA Bases Revealed by Ultrafast Vibrational Spectroscopy
(2008-04) Middleton, Chris; Kohler, Bern
To better understand the link between light absorption and deleterious DNA photoproducts, the photophysics of DNA bases was investigate with femtosecond mid-IR transient absorption spectroscopy. Markers band for two excited states, a dark singlet state and a triplet state, were found. These marker bands provide insight into the nature and dynamics of the states. The results confirm a model for pyrimidine bases previous proposed based on UV-visible transient absorption measurements. This study provides an important foundation for future investigations of the role of these states in DNA.
Raccoon Social Behavior in a Highly Urbanized Environment: A Genetic Investigation
(2008-04) Hauver, Stephanie; Gehrt, Stanley
Raccoons are heavily studied due to their importance as fur bearers, nest predators, and transmitters of zoonotic diseases such as distemper and rabies. Yet despite many investigations little is known of their social behavior because of their nocturnal, secretive habits. Raccoons are often described as solitary and intolerant of conspecifics, but instances of group foraging, den cohabitation, and male coalitions have been documented. Factors responsible for this selective sociality remain unknown. The theory of kin selection states that cooperation and sociality easily evolve between related individuals, and indeed, many species that are selectively social associate with kin. However, reciprocation theory and the theory of resource abundance have also been used to explain the sociality of certain species. Therefore, the purpose of this research is to discern if relatedness is a major factor in raccoon sociality. This study was conducted in a Forest Preserve park in suburban Chicago where over 1.5 million visitors may attend the park annually, leaving substantial amounts of refuse behind. Raccoons within the park were trapped, anesthetized, aged, weighed, radio collared, and blood was drawn for a genetic sample. Blood samples were analyzed using PCR techniques and 16 highly variable microsatellites. Relatedness values were calculated using the software KINSHIP. The radio collars used for this study were equipped with newly developed proximity detecting capabilities. Proximity detectors are equipped with both VHF (very high frequency) and UHF (ultra high frequency) signals which allows for traditional telemetry but also have the capability to record when two or more individuals "contact" each other. A contact is defined as when two or more individuals come within one meter of each other. The collars will also record the date and time contact was initiated, the duration of the contact, and the id number of the contacted collar. Contacts are stored in the collar's internal memory until data can be downloaded via interface and portable computer. These contact data, along with home range and distance between home range estimates were analyzed in relation to relatedness values. Relatedness values between females (FF) were significantly higher than those between males (MM), or between females and males (MF). This result is indicative of male dispersal which has been suspected for urban raccoons, but never confirmed with a genetic investigation. Percent home range overlap and distance between home ranges did not correlate with genetic relatedness. Contact rates were neither higher nor lower among related individuals. Additionally, 605 instances of den sharing were recorded of which 458 occurred between unrelated individuals (182 MM, 219 MF, 57 FF) The results of this study contribute to a growing number of species that have social associations with non-kin. These results yield important empirical evidence for the theoretical study of how social behavior evolves. Additionally, wildlife managers and public health officials may be aided by this knowledge as it relates to one of the most abundant, and often problematic, North American mammals.
Bilateral Free Trade Agreements – How do Countries Choose Partners?
(2008-04) Singh, Suresh; Makhija, Mona
While the debate on whether countries should or should not sign trade agreements with selected partners continues, governments have significantly stepped up the rate at which they enter into such agreements. A number of such agreements have been signed lately and many more are under negotiation. Multinational firms get impacted by these agreements irrespective of whether these are beneficial to the participating economies in particular or to the world economy in general. Bilateral free trade agreements constitute a very large proportion of the trade agreements between countries. Knowing which two countries are more likely to sign a free trade agreement can help multinational firms minimize risks or maximize opportunities arising from the recent proliferation of such agreements. This paper finds that geographical distance and relative strength of industry pressure groups are two factors that govern which two countries are more likely to enter into a bilateral free trade agreement with each other.
MicroRNAs act as decoy molecules to inhibit the function of RNA binding proteins
(2008-04) Eiring, Anna M.; Perrotti, Danilo
Altered microRNA (miRNA) expression contributes to aberrant post-transcriptional gene regulation in several types of cancers; however, their role in the progression of chronic myeloid leukemia (CML) from chronic phase (CML-CP) to blast crisis (CML-BC) is still largely unknown. To gain further insight into the role of miRNAs in CML disease progression, we used microarray-based techniques to analyze miRNA expression in CML-BCCD34+ compared to CML-CPCD34+ progenitors and in BCR/ABL-expressing myeloid cell lines compared to untransformed controls. Using this method, we identified a discrete number of miRNAs either upregulated (34 miRNAs) or downregulated (14 miRNAs) in both BCR/ABL+ cell lines and primary patient samples. Among the downregulated miRNAs, we focused our attention on miR-223 because of its reported role in myelopoiesis, miR-15a/16-1 because of their reported role as tumor suppressors, and miR-328, a miRNA with no currently known function. Northern blot and qRT-PCR analyses validated the results of our microarray analysis, revealing a marked reduction in miR-223, miR-328, miR-15a, and miR-16-1 expression in 32D-BCR/ABL and K562 cells (50-75% inhibition), and expression of these miRNAs was rescued upon treatment of cells with the tyrosine kinase inhibitor imatinib (2 mM; 24h). Interestingly, sequence analysis of both miR-223 and miR-328 revealed homology with the hnRNP E2-mRNA binding site contained in the uORF spacer region of the CEBPA 5’ UTR (CEBPA 5’ uORF). hnRNP E2 is the RNA binding protein responsible for block of myeloid differentiation in CML-BCCD34+ progenitors, and does so by binding to the CEBPA 5’ uORF to block its translation. Indeed, REMSA experiments revealed that synthetic miR-223 and, to a greater extent, miR-328, could bind efficiently to recombinant hnRNP E2 protein in vitro and compete for its binding to an oligoribonucleotide containing the CEBPA 5’ uORF. Similarly, REMSA and UV-crosslinking showed that both miR-223 and miR-328 could bind endogenous hnRNP E2 from lysates of BCR/ABL-expressing but not parental cells, as well as from lysates of parental 32Dcl3 cells ectopically expressing a Flag-tagged hnRNP E2 protein. These results suggested that miR-223 and miR-328 may act as decoy molecules to interfere with the translation-regulatory activity of hnRNP E2. Consistent with this hypothesis, ectopic expression of miR-223 and, to a greater extent, miR-328, was capable of restoring G-CSF-driven granulocytic maturation of differentiation-arrested 32D-BCR/ABL cells and CML-BCCD34+ cells. Furthermore, C/EBP-alphaprotein levels were markedly increased in both miR-223- and miR-328-expressing 32D-BCR/ABL cells as well as in primary CML-BCCD34+ patient samples. Finally, while ectopic expression of miR-223, miR-328, miR-15a, or miR-16-1 had no significant effect on the viability of normal or BCR/ABL-expressing cells, ectopic expression of miR-15a/16-1 or miR-328 significantly impaired BCR/ABL-dependent colony forming ability (miR-15a/16-1: 65-75% inhibition, P<0.001; miR-328: 40-50% inhibition, P<0.01). Altogether, these data reinforce the importance of BCR/ABL-dependent post-transcriptional gene regulation during CML disease progression. Furthermore, they suggest a novel function for miRNAs as regulators of RNA binding protein activity and provide a paradigm-shift for miRNA function as currently understood.
Stereotypes and the Bottom Line: Learning Lessons from Gender Based Firing Discrimination Cases
(2008-04) Byron, Reginald; Roscigno, Vincent
Despite years of research on gender inequality in hiring, promotion, and wages, virtually no research has examined how gender based firing discrimination occurs in contemporary workplaces (Peterson and Saporta 2004). Studying firing discrimination remains important given its relationship to unemployment for the victim as well as considerable litigation costs to business owners. This study uses a unique quantitative and qualitative data set of firing discrimination complaints filed by White and African American women to the Ohio Civil Rights Commission (1986-2003). Aggregate descriptive trends of 2,030 of these cases demonstrate that African American women, largely due to their relatively small population size, file gender based firing discrimination at dramatically higher rates than White women. However, a qualitative immersion into over 75 of these cases reveals that, regardless of race, women experience similar processes in gender based firing cases. The vast majority of women were fired because of 1) issues regarding pregnancy/maternity leave, 2) performance related differential treatment, or 3) retaliation for making a prior complaint about discrimination. This paper contributes to the literature by offering empirical insight into how gender based firing discrimination unfolds and also provides some practical recommendations to organizations.
Monitoring composition and flavor quality of Cheddar cheese during ripening using a rapid spectroscopic method
(2008-04) Subramanian, Anand; Rodriguez-Saona, Luis
About 9.13 billion pounds of cheese is produced in the US every year, of which 34% is cheddar cheese. Cheddar cheese composition and flavor quality, which influence the consumer acceptance, price and food processing application, develop during the ripening process. However, ripening is not well understood due to complexity of the process and heterogeneous nature of cheese. Rapid monitoring of composition and flavor quality of cheese and understanding cheese ripening hold many advantages for the cheese-maker. Cheese composition and quality are currently determined using chromatographic techniques and trained human expert sensory panels, which are expensive and time consuming. Rapid methods capable of simultaneous monitoring of multiple components can save time and money. Fourier transform Infrared (FT-IR) spectroscopy, which monitors the light absorbing properties of chemical compounds, can be used as a rapid, inexpensive, and sensitive method to analyze cheese quality. Unlike many chromatographic techniques, FT-IR spectroscopy provides unique overall chemical fingerprints of cheese samples that can be analyzed through multivariate statistical techniques to rapidly determine cheese composition and flavor quality. Hence the objective of this research was to develop a rapid method based on FT-IR spectroscopy to monitor composition and flavor quality of Cheddar cheese during ripening. Twelve different Cheddar cheese samples ripened for a period of 73 days were provided by a commercial cheese manufacturer, along with their final moisture, pH, salt, fat content and flavor quality data. Samples were collected on days 7, 15, 30, 45 and 73 during ripening and analyzed for organic acid content using chromatographic techniques (reference method). For FT-IR analysis the samples were treated using organic solvents and the extracts were dried on zinc selenide crystal and scanned in the spectrometer (4000-700 wavenumbers). Infrared profiles (spectra) of the samples were matched with their composition and quality data to develop multivariate statistical regression and classification models. The infrared spectra of the samples were well defined, highly consistent within each sample and distinct from other samples. The regression models showed excellent fit (r-value>0.95) and could determine moisture, pH, salt, fat, organic acid contents in less than 20 min, which is significantly less than the current methods. Furthermore, cheeses could also be classified based on their flavor quality (sour, whey taint, good cheddar, etc.). The discrimination of the samples was due to organic acids, amino acids and short chain fatty acids (1800 to 900 cm-1), which are known to contribute significantly to cheese flavor. FT-IR spectroscopy based method shows great promise as a rapid, simple and cost-effective analytical and quality control tool for the industry. It will enable monitoring and controlling cheese ripening process to produce cheese of desired quality. For the cheese industry, this can be an extremely valuable tool as it will enable identification of quality defects early in the ripening process. The identification of defects will assist in deciding whether the cheese is marketable prior to incurring storage and interest charges associated with aging as well as deciding the future application of the cheese.
Antoine Jean-Gros's "Hercules and Diomedes": a return to the Baroque
(2008-04) Wills, Carrie; Shelton, Andrew
During the Napoleonic Empire, the French artist Antoine-Jean Gros received a great deal of acclaim for his monumental, dynamic paintings of modern subjects such as “Napoleon Visiting the Pest House at Jaffa” and “The Battle of Eylau”; however, in the last years of his career, he produced a series of highly criticized mythological canvases. While scholars often point to the ostensibly paralyzing influence of Gros’s former master, Jacques-Louis David, as the impetus behind this radical change in style and subject during his late career, I assert that Gros, far from disavowing his own artistic inclinations, set forth a new model of classicism in 1835 with his widely criticized painting “Hercules and Diomedes”—a model that might renew an interest in the style and subjects of the great masters in a time when monumental, heroic history paintings were rapidly disappearing in France. Gros, as the newly elected President of the French Academy, created his last large-scale painting, “Hercules and Diomedes,” as an attempt to regain control of the French school. In a letter to Louis-Adolphe Thiers, the Minister of the Interior, Gros refers to his “Hercules and Diomedes” as, “mon tableau...que j’ai eu le courage de faire, dans le but d’un rappel aux hautes études, puisque les succès en peinture semblent, en ce moment, être d’autant plus grands qu’ils s’en éloignent davantage.” Gros’s subject, the rarely depicted eighth labor of Hercules, certainly presented the opportunity to display the struggling, heroic male nude that had been an essential element of Davidian Neoclassicism; however, I believe that Gros was looking to the work of the first leader of the French Academy, Charles Le Brun, as an inspiration for his last monumental painting. In 1640, the youthful Le Brun was commissioned by Cardinal Richelieu to paint his “Hercules Vanquishing Diomedes,” and the compositional similarities to Gros’s work are striking. As the First Painter to Louis XIV and the primary artist involved in the decoration of Versailles, Le Brun was a legitimate model of emulation for younger artists and offered an alternative to the static classicism of David. His dramatic and dynamic style would, without a doubt, be more engaging for a younger generation of artists coming of age during the rise of Romanticism. Gros’s depiction of the eighth labor of Hercules placed him in line with not only Charles LeBrun, but also a more recent President of the Academy who had chosen LeBrun’s “Hercules Vanquishing Diomedes” as a precedent for his own painting. Jean-Baptiste Marie Pierre, the President who was so often at odds with the young David during the years just prior to the Revolution, painted his version of the story, “Diomedes, Slain by Hercules,” in 1742 as his reception piece to the Academy. The compositional similarities to Le Brun’s work are undeniable, indicating not only that Le Brun’s work had been an inspiration to a former President of the Academy but also proving that, regardless of David’s opinion of Pierre, Gros sought to establish a recognizable, legitimate classical tradition that could be linked to these two great academic leaders of the past. Unfortunately for Gros, his attempt to lead by example can only be described as a resounding failure, as the Salon audience regarded “Hercules and Diomedes” as a tragic reminder of how far Gros had strayed from his great Napoleonic works; however, this painting was Gros’s last effort as the most prominent classical artist in France to regain control of the French school before his death by suicide later that year. He offered the younger generation of artists an alternative model of classicism which did not carry the stylistic constraints and negative political associations of Davidian Neoclassicism. Looking to Charles Le Brun and his treatment of this very unusual subject allowed Gros to make use of his own talent for dynamic, colorful compositions while presenting a new, reinvigorated kind of classicism based on the style of the famous Baroque master and one-time leader of the French Academy.
Bioarchaeology of Life and Death in Colonial South America: Systemic Stress, Adaptation, and Ethnogenesis in the Lambayeque Valley, Peru AD 900-1750
(2008-04) Klaus, Haagen; Larsen, Clark
The last 10,000 years witnessed a handful of major historical and biological transformations – the most recent and violent of which was contact between Native Americans and Europeans. It has long been assumed contact resulted in indigenous biological, demographic, and cultural collapse. Recently, bioarchaeologists in North and Central America uncovered evidence encoded in human skeletal and dental remains revealing increased native morbidity following contact. Yet, almost nothing is known of indigenous postcontact culture and behavioral adaptations. Moreover, the bioarchaeology of historic South America remained essentially unwritten. This research unites the study of human burials and skeletal remains to establish the first empirical and holistic study of postcontact culture and biology in the Central Andes on the north coast of Peru. Here, three hypotheses are tested: (1) the indigenous Mochica of the Lambayeque Valley could not escape health burdens created by Spanish colonialism; (2) Colonial Mochica burials represent involuntary conversion and adoption of Catholic rituals, and; (3) depopulation, always assumed but never tested, resulted in substantial loss of genetic diversity. Excavation and data collection since 2003 generated a sample of 1,048 skeletons spanning A.D. 900-1750. The hypotheses were tested using independent lines of data derived from archaeology, ethnohistory, burial patterning, skeletal pathological conditions that record multiple forms of biological stress, and inherited dental traits. The Colonial Mochica indeed experienced increased biological stress. Paleodemographic reconstructions indicate the sensitive balance of female fertility was disrupted as postcontact birth rates plummeted. Quantitative epidemiological analysis of acute childhood stress recorded in dental enamel defects reveals many children died rapidly from diseases such as smallpox. Cranial lesion among the survivors shows increased levels of childhood iron deficiency anemia. Among adults, increased chronic skeletal infection is clear. Spanish labor extraction resulted in radical lifestyle alterations, evidenced by elevated prevalence of traumatic injury and destructive osteoarthritis lesions in arm and knee joint systems. Markedly poor postcontact oral health reveals a shift to a less nutritious diet. Yet, under these conditions, the Mochica did not culturally collapse, but initiated a creative cultural interchange involving formation of hybrid Catholic-Mochica burial practices incorporating pre-Hispanic soul-transfer and fertility rituals. Population genetic analyses of dental traits indicate major postcontact genetic transformation. This was not linked to depopulation, but unprecedented high levels of gene flow. The Mochica apparently widened local mating networks and the definition of ethnicity among themselves as a survival strategy, resulting in a valley-wide hybrid native coalition. We accept the first hypothesis and reject the latter two. Lambayeque, Peru did not experience a stereotypical postcontact disaster. This research tells the story of a group of Andean people, who, despite unprecedented biological stress, adapted to the Colonial reality through ethnogenesis: the creation of a new kind of society, grounded in a process of local biological hybridization paralleled by cultural hybridization with European customs and religion. Methodologically, this study unites sources of anthropological information traditionally treated as separate domains, and operationalizes a new configuration of theory and method in the study of burials to create dynamic, holistic, and humanized reconstructions of the past.
Seeing and manipulating spin-spin interactions at the single atomic level
(2008-04) Lee, Donghun; Gupta, Jay A.
The 2007 Nobel prize in physics went to Albert Fert and Peter Grünberg “for the discovery of Giant Magnetoresistance (GMR)” which is an effect that underlies all of the read sensors in today’s hard disk drives. These initial studies of GMR have opened a new paradigm for future electronics called ‘spintronics’. In contrast to conventional charge-based electronics, spintronics relies on the electron’s spin, which is a fundamental magnetic moment that has two energy states, spin-up or spin-down, analogous to the 1 or 0 states of a bit in a computer. One key challenge for the realization of spintronics is the development of ferromagnetic semiconductors which could potentially combine magnetic recording and digital logic in a single device. One promising candidate is GaMnAs, in which nonmagnetic GaAs can be made ferromagnetic by introducing only a few percent of Mn. The low ferromagnetic transition temperature (currently Tc<-100C) of GaMnAs, prevents use in practical devices which operate at room temperature. A better understanding of GaMnAs at a microscopic level is necessary to probe the limits of Tc in this material. We have built a low temperature (-260C) ultrahigh vacuum scanning tunneling microscope (STM) to study spin-spin interactions in GaMnAs at the atomic level. Our STM can be used to image semiconductor surfaces with atomic resolution, manipulate individual Mn atoms, and spectroscopically probe Mn-Mn interactions. A clean GaAs surface is prepared by cleaving a p-type GaAs crystal inside the ultrahigh vacuum chamber. A low coverage of Mn atoms is then evaporated onto the surface. To more closely mimic a bulk-like environment, single Mn atoms can be substituted for Ga in the first layer of the surface, by applying a voltage pulse with the STM tip. To study Mn-Mn interactions, we make pairs of substituted Mn. Our STM studies on Mn pairs show interesting spin-spin interactions which strongly depend on the Mn separation and relative crystal orientation. For example, coupling between two Mn atoms switches from ferromagnetic (parallel spins) to antiferromagnetic (antiparallel spins) depending on the pair’s orientation. We are also developing a capability for spin-polarized STM to better study long range magnetic ordering between pairs and larger clusters of substituted Mn. By using a magnetic STM tip such as Ni or Cr, spin-polarized STM can selectively detect different spin states of Mn clusters. These studies will contribute to a microscopic understanding of the underlying physics of GaMnAs, and will help in the search for new semiconductor materials which exhibit ferromagnetism above room temperature.
Biocultural Implications from Scanning Electron Microscopy of Prehistoric Human Dental Calculus, Ohio
(2008-04) Blatt, Samantha; Sciulli, Paul
Dental calculus, though it provides a unique calcium reservoir of bacteria and dietary debris seldom preserved elsewhere in the archaeological record, is an overlooked source of data in anthropological literature. Small particles of archaeobotanical debris can adhere and become incorporated into unmineralized plaque on teeth during mastication. The physical inclusion of bacteria and archaeobotanical debris in the matrix of calculus is direct evidence for the contemporaneity of both structures, because the mineralization of dental plaque occurs only in the presence of saliva. This research reassesses the value of collecting human dental calculus from archaeological remains and provides insight into the oral health and diet of prehistoric Native Americans in northern Ohio. Samples of dental calculus (n=19) were collected from the Danbury site (33OT16) in Ottawa County, Ohio inhabited from the Late Archaic through Late Prehistoric periods. Analysis yielded a variety of noticeable inclusions, including both mineralized bacteria, calcium-phosphate (CaP) crystalline structures, and numerous phytoliths (amorphous, grass, and non-grass types). Most importantly, cellulose fibers consistent with cotton were found in the calculus of four Late Woodland individuals and the implications of long-distance interaction suggested by this find are discussed. SEM analysis of was limited, however, by the disaggregation of debris and the lack of standardization of phytolith and starch grain classification.
Making art, making choices: A study of the art and writing of youthful offenders
(2008-04) Hinshaw, Wendy; Hesford, Wendy
This research examines how students incarcerated at a juvenile corrections facility for girls respond to an art program facilitated by a community arts organization, ArtSafe. ArtSafe is a non-profit arts education organization in Ohio that provides programming on a regular basis at the facility. In the midst of declining state and federal funding for prison rehabilitation programs it is increasingly important that programs like ArtSafe survive and develop in corrections facilities across the country. This study of a corrections arts program reveals how students negotiate the goals of the art program, designed to enhance their choice-making skills and build their self-esteem and self-confidence, in the context of a carceral institution that emphasizes conformity and control. This study employed participant-observation to gather data in art classes offered between June and December 2006 at a juvenile corrections facility in Ohio, and applies methods of discourse analysis to the data in order to analyze patterns in the representations created in the students’ art projects, as well as patterns in the spoken and written discourse provided in the students’ interviews. Participant-observation is a qualitative research method designed to gain familiarity with a given group of individuals. Discourse analysis analyzes how social relationships and dominant cultural assumptions are articulated through patterns in verbal and non-verbal communication. This project teaches us a great deal about how youthful offenders learn in different programming environments, as well as about the various factors that influence their learning. Research of this corrections art program found that the students use their art to negotiate various assumptions about criminality and incarceration that structure their environment. Through their art and writing the students question and engage elements of their classroom and institutional environments, and also reject simplistic distinctions between “criminal” and “victim” that circulate in our culture at large. The students identify themselves through their art and writing with times and spaces that extend beyond their convicted offense and current institutional location, and focus on experiences and relationships that help them create an alternative to the institutional identity formed within the corrections facility. This also represents the spatial negotiation that takes place between the art class students and facilitators, as well as the art facilitators and the institution as a whole. Because ArtSafe emphasizes choice-making and individual empowerment in its teaching practices, the teachers must integrate the individual freedom that is at the heart of art-making with the rules and customs of the institution. This research reveals how individuals intimately involved with the criminal justice system (the art class students as well as the facilitators and institutional staff) are affected by and also respond to discourses of criminality, incarceration, and victimization that operate in their immediate institutional environment as well as in the culture at large. Ultimately this research enhances our understanding of the perspectives of youthful offenders on programming offered at juvenile corrections institutions, as well as our understanding of the changing strategies of approach in prison programming.
Increased IL-12 induced STAT-4 signaling in CD8 T cells from aged mice
(2008-04) Rottinghaus, Erin; Turner, Joanne
Aging is associated with poor immune function leading to increased susceptibility to infectious diseases and the development of immune associated disorders. Specific deficiencies in CD4 T cell function have been identified whereby CD4 T cells from old mice have defective T cell receptor mediated antigen-specific responses compared to young T cells. Several of the defects described in T cells in old age can be attributed to dysfunctional cell signaling through the T cell receptor. Immune cell function is also dependent on cytokine production, and the capacity of cells to respond to cytokines. We have previously shown that a subset of CD8 T cells from the lungs of aged mice produce IFN-γ when exposed to IL-12 in an antigen-independent manner. Furthermore, IL-12 responsive CD8 T cells are present in apparently healthy old mice and represent a population that can mediate early non-specific control of Mycobacterium tuberculosis. For this reason understanding the mechanism underlying their ability to respond to IL-12 in the absence of a TCR signal may identify an alternate pathway to optimize protective immune responses in the elderly. We investigated the ability of CD8 T cells from old mice to respond to IL-12 by determining the expression of the IL-12 receptor on the surface of young and old CD8 T cells, as well as by quantifying the activation of the downstream signaling molecule, STAT-4. We found IL-12Rβ2 expression on pulmonary CD8 T cells to be equivalent between young and old mice, and therefore hypothesized that IL-12 signaling in pulmonary CD8 T cells was increased in old age. To test this hypothesis, single cell suspensions from young and old mice were given IL-12 for 4 hours, and STAT-4 phosphorylation in CD8 T cells was determined using flow cytometric analysis. In response to IL-12, pulmonary CD8 T cells from old mice had increased levels of phosphorylated STAT-4 within individual CD8 T cells, and old mice possessed significantly more CD8 T cells that could phosphorylate STAT-4 in response to IL-12 compared to young, leading to an increased number of CD8 T cells that could secrete IFN-γ. To confirm STAT-4 activation was a direct consequence of IL-12 stimulation, STAT-4 phosphorylation was determined in purified CD8+ cells from young and old mice. IL-12-induced STAT-4 phosphorylation was detected in purified CD8+ cells from both ages of mice, illustrating that IL-12 could act directly on CD8+¬ cells. Importantly, the proportion of CD8+ cells that could phosphorylate STAT-4, and the amount of phosphorylated STAT-4 in each cell was significantly greater in CD8+ cells from old mice. These data demonstrate that old mice possess a substantial population of CD8 T cells exhibiting increased STAT-4 phosphorylation in response to IL-12, which ultimately leads to enhanced IFN-γ production. We therefore define a mechanism for the increase in IL-12-induced IFN-γ secretion by CD8 T cells in old mice. A more comprehensive understanding of the unique contribution of CD8 T cells to innate immunity in old mice could lead to the development of more efficacious therapies in the elderly for combating pulmonary infections.
Heterogeneity and Pliability of Tumor-educated Macrophages
(2008-04) Roberts, Ryan; Marsh, Clay
Cancerous tumors survive, in part, by learning to manipulate the cells around them. Many tumors stimulate one type of white blood cell, the macrophage, to adopt behaviors that facilitate tumor growth and metastasis. Our recent data suggest that these pernicious behaviors elicited by tumor education may arise from discrete populations of tumor-educated macrophages. More importantly, it appears that many of these effects can be reversed. Contrary to what one might predict based on the current literature, elimination of macrophages from similar tumor-bearing mice using a genetically-engineered macrophage ablation model accelerated tumor growth and metastasis. This outcome appears to result from the biological effects of macrophage ablation, which include a reactive increase in levels of macrophage precursors—blood monocytes. Our data suggest that particular groups of infiltrating monocytes may respond to tumor education in ways that promote tumor progression, while other monocyte-macrophage populations act in ways that prevent tumor growth and benefit the host. The effects of tumor education on these cells can also be reversed: When we treated mice bearing mammary tumors with intratumor GM-CSF (a natural stimulator of monocyte-macrophages), we observed a phenotype switch in the tumor-educated macrophages. GM-CSF treatment caused these cells to switch from behaviors that stimulated angiogenesis (new blood vessel growth in support of increasing tumor size) to behaviors that inhibited blood vessel and tumor growth. This change is marked by the expression of the soluble VEGF receptor, which inhibits the primary angiogenic signal. Results include slower tumor growth, reduced metastasis, lower tumor oxygen levels, and fewer, more normalized blood vessels within the tumor. These data suggest new approaches to cancer therapy in which the treatment modifies the behavior of non-tumor cells, causing them to attack the tumor.
How long does depression at cancer diagnosis affect a patient’s health?
(2008-04) Brothers, Brittany M.; Andersen, Barbara L.
PURPOSE OF THE STUDY: Many breast cancer patients report depressive symptoms at diagnosis. Although depressive symptoms improve, it is unknown whether women fully recover into the survivorship years, as previous studies have been cross-sectional or only short-term. RESEARCH METHOD: Breast cancer patients were accrued following surgery and prior to adjuvant therapy (baseline) and then followed for 5 years. Measures of psychological and physical functioning (both patient and nurse-rated) were used. Baseline CES-D scores (11-item version) were used to classify patients as clinically depressed (scores > 10; n = 45; DEP) or non-depressed (scores < 10; n = 182; NON-DEP). FINDINGS: Using mixed model analyses, trajectories of physical and psychological functioning over 5 years for the groups were compared. For physical functioning (KPS and signs/symptoms of illness/treatment), the DEP group had poorer outcomes from baseline through 12 months (ps < .01). Over time, both groups gradually improved in physical functioning in a similar pattern (ps > .12). The psychological trajectories--depressive symptoms (CES-D), stress (IES), and quality of life (SF-36 mental and physical components)--were of similar form. Across outcomes, the DEP group had poorer functioning at baseline (ps < .001) and this difference was maintained through 24 months (ps < .05). The groups were equivalent thereafter (ps > .39). IMPLICATIONS: Significant depressive symptomatology at cancer diagnosis portends impaired functioning for years. For such individuals, physical symptoms remain significantly elevated through 12 months, and poorer quality of life and high levels of cancer-specific stress extend for another year. Only after 2 years do women depressed at diagnosis appear to attain a level of recovery similar to that of those not depressed at diagnosis. Thus, interventions are needed for patients vulnerable to slowed physical and psychological recovery from cancer.
Deciphering the mechanism of myocardial relaxation: The first step to the cure for diastolic dysfunction in heart disease
(Pflugers Archiv-European Journal of Physiology, 2008-04) Monasky, Michelle; Janssen, Paul
Diastolic dysfunction can impair ventricular filling, and can be a major contributor to the cardiac dysfunction in heart failure. In the clinic, approximately half of patients with congestive heart failure (CHF) present mainly with diastolic dysfunction. It stands to reason that in order to understand the mechanism governing diastolic dysfunction, it would first be necessary to understand how myocardial relaxation takes place in the non-pathological setting. We hypothesize that myofilament properties, rather than calcium transient decline, primarily determines duration of relaxation in adult mammalian myocardium. To test this hypothesis, we simultaneously measured force of contraction and calibrated [Ca2+]i transients in isolated, thin rabbit right ventricular cardiac trabeculae (n = 8), at various lengths at 37 ºC. Time from peak tension to 50% relaxation (RT50(tension)) increases significantly with length (from 49.8 ± 3.4 ms to 83.8 ± 7.4 ms at an [Ca2+]o of 2.5 mM), while time from peak calcium to 50% decline (RT50(calcium)) was not prolonged (from 124.8 ± 5.3 ms to 107.7 ± 11.4 ms at an [Ca2+]o of 2.5 mM). Analysis by two-way ANOVA revealed that RT50(tension) is significantly correlated with length (P < 0.0001). At optimal length, varying the extracellular calcium concentration increased both developed force and calcium transient amplitude, but RT50(tension) remained unchanged (P = 0.90), while intracellular calcium decline actually accelerated (P < 0.05). Thus, an increase in muscle length will result in an increase in both force and duration of relaxation, while the latter is not primarily governed by the rate of [Ca2+]i decline. Our data provide further insight into the mechanism of myocardial relaxation, and the results show that increasing muscle length significantly dissociates intracellular calcium transient decline from force decline. In conclusion, when investigating cardiac relaxation disorders, myofilament properties need to be prominently considered for strategizing future treatment options.
The Teachers’ Sense of Multicultural Efficacy Scale: Construction and Validation
(2008-04) Silverman, Sarah Kozel; Davis, Heather
Sense of efficacy, or one’s belief in his or her ability to facilitate change, has been cited as a predictor of many valuable educational outcomes for both students and teachers. Scales designed to measure teachers’ sense of efficacy have been developed in an effort to indentify both the best predictors of student and teacher success and reliable indicators of those predictors. The purpose of the current study was to develop a measure of teachers’ sense of efficacy for multicultural education. Whereas previous scales have measured only teachers’ sense of efficacy for general teaching tasks, they have not investigated the myriad aspects of multicultural education that may impact teacher efficacy. Because strong teacher efficacy has been linked, for example, with high student achievement, low efficacy for certain aspects of education may translate to low achievement. The Teachers’ Sense of Multicultural Efficacy Scale (TSMES) provides a manner of measuring teacher efficacy specifically for educating diverse students and for education about issues relating to diversity.
Longitudinal Relations between Maternal Gatekeeping and Father Responsibility
(2008-04) Cannon, Elizabeth A.; Schoppe-Sullivan, Sarah J.
The current study examined relations between child characteristics and father responsibility and maternal gatekeeping (mothers’ attempts to either limit or encourage fathers’ parenting) and father responsibility across the infant’s first year using self-report and observational data from 64 two-parent families. Results showed that child gender and temperament interacted in relation to father responsibility, such that fathers were more involved with difficult boys and less involved with difficult girls. Furthermore, positive and negative dimensions of maternal gatekeeping were related to different types of later father responsibility. Implications of these findings are discussed.
We Shall Lead: Freedom Schools and the Creation of Black Youth-based Leadership
(2008-04) Sturkey, William; Jeffries, Hassan
The goal of this paper is to examine the response to, and judge the effectiveness of, the Freedom Schools that were built and conducted by the Student Non-violent Coordinating Committee (SNCC) during its 1964 Freedom Summer project. Prior to this protest, African Americans in Mississippi were mired in one of the deepest states of educational poverty seen in modern American history. Only seven percent of the state’s black residents even held a high school diploma in 1964. Many black residents did not know how many states composed their country, or even what its capital was. A lot of them did not even know about the rights guaranteed to them by the 14th Amendment passed nearly 100 years before. To remedy this situation, SNCC brought hundreds of college-aged volunteers into the state during the summer of 1964. The research methods used for this paper vary greatly and include a variety of secondary sources, the vast collection of SNCC Papers, letters from volunteers, letters from students, various accounts recorded in diaries and programs, pictures, and even the actual projects done by the dynamic black students in 1964 in order to understand the effectiveness of the Freedom Schools. My research indicates that the Freedom Schools were by far the most successful aspect of the Summer project. Black youths attended the schools at more than 200% of the rate expected by SNCC. These students were incredibly enthusiastic and instantly became active leaders in their communities. After only a few weeks in the schools, African American children started leading sit-ins, voter registration campaigns, and creating their own organizations. In Hattiesburg, junior high students started a program for middle-aged adults where they would teach them how to fill out voter registration cards. The implications of this research are widespread. First, as several noted scholars have observed, Freedom Schools have often been overlooked, both then and now. The schools were largely considered to be women’s work and more attention was paid to other activities occurring during the 1964 protest. This paper not only discusses the strong role that women played in the project, but also forces historians to re-think the achievements of the civil rights movement. This research also follows a current trend in civil rights history that looks at the importance of grassroots activism. The Freedom Schools, I argue, were the purest form of grassroots activism to occur during the modern African American freedom struggle. They were based on the model developed by Myles Horton at the Highlander Folk School. This model of citizenship learning spread throughout the South during the 1940s and 1950s and became one of the most important ideological bases for the civil rights movement. This research on the Freedom Schools shows the power of this model. Freedom Schools became one of the most encouraging aspects of the civil rights movement, and this paper argues that this model should be copied for use in future protests or activism.

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