Most procedures for DNA transformation of chloroplasts involve the use of circular DNA as vectors and green leaves as the target tissue. Although such procedures are successful with some plants, they are inefficient and do not work with other plants, especially monocots. In maize, plastid DNA (ptDNA) is comprised largely of linear molecules. Furthermore, ptDNA is rapidly degraded as the cells become green. In consequence, the introduction of transgenes into maize chloroplasts has been problematic. In order to create vectors for monocot transformation, the plastid chromosome is most efficiently targeted in its natural form. Previous work suggests that the plastid chromosome is found primarily in a complex, branched linear form with defined ends. We chose one of these ends, “End 1,” which is near an origin of replication, as our target for transgene integration. We constructed vectors with the “End 1” gene sequences and a mannose-metabolizing transgene, PMI, as the selectable marker. Plastid transformation was performed by particle bombardment using gold microcarriers coated with either the circular or linear vector. The successful introduction of a transgene using the “End 1” DNA sequence indicates that the transgene integrates either by end joining of the linear vector to the linear ptDNA or by homologous strand invasion. Thus, using a linear vector with an end sequence produces optimized results when engineering monocot plastid transformants.

Obesity is a major cause of health-related problems in the developed world and recently studies have demonstrated a link between environmental factors and obesity. 2,2’,4,4’-tetrabromodiphenyl ether (BDE-47) is one toxic chemical used as a flame-retardant in consumer products. BDE-47 contaminants are commonly found in dust, air, and soil and their accumulation in the food chain contributes to significant levels found in humans, particularly children. Recent studies have linked BDE-47 to a range of toxic impacts, including disruption of insulin signaling. The objective of this study is to investigate the in vivo effects of BDE-47 in hepatic metabolism. We hypothesize that the drug will cause increased cell injury, inflammation and accumulation of fat within the liver (hepatic steatosis) and will have significant effects on individuals predisposed to disruption in insulin signaling. In order to disrupt insulin signaling in vivo, we have generated mouse models with liver-specific deletion of Tsc1 and Pten, negative regulators of mTORC1 and Akt respectively. Both of these complexes play critical roles in the cell cycle and insulin metabolism within the liver. Cohorts of Tsc1-/-, Pten-/-, and control mice were exposed to BDE-47 or placebo for six weeks within their first 10-12 weeks of life. During exposure, the mice were tested for insulin sensitivity and glucose tolerance. Liver tissue was also tested for several markers of hepatic insulin signaling post-mortem. Differences in impacts on these genetic mutants could indicate if the BDE-47 targets the Akt or mTOR cascades differently and if those predisposed to aberrations in insulin signaling may be more sensitive to the toxic effects of BDE-47. This study will determine if a significant interaction between the environmental influence of BDE-47 and the genetic deregulation of insulin signaling occurs, which could have deleterious implications for the use of these compounds in consumer products in the future.

Visual-Motor processing provides a mechanism for animals to translate visual cues into useful information for locomotion. My research aims to investigate this mechanism by analyzing the responses made by fruit flies to certain visual stimuli. I accomplish this by first tracking and quantifying fruit fly locomotion when two flies are present. By quantifying this behavior I can create a behavioral map of fly responses in relation to other fruit flies. I can then replace one of the flies with a cylindrical, fly-sized magnet that is readily controlled by me. This step is important because by controlling the magnet it is possible to reproduce large amounts of a specific behavior, instead of watching two flies interacting randomly and waiting for relevant interactions. It also will allow me to investigate the affects of object speed and angle of approach and create a behavioral map of the fly's locomotor response. Once this is accomplished it will then be possible to test fruit fly responses to visual stimuli presented on an LED screen surrounding the fly and to measure brain activity in the flies while these stimuli are displayed. Ultimately we hope to identify the neurons that are responsible for visual-motor processing and how they accomplish the transition from visual input to locomotor response.

The Arctic is receving global attention as climate change transforms the region. With increased interest in natural resources and sovereignty issues, the security discourse in the Arctic is also changing. This Taskforce report seeks to understand Arctic security as the capacity for communities and states to build sustainable and resilient systems and to assert a representative voice, in arenas of diplomacy and negotiating power. The Taskforce group spent one week in Quebec City and Ottawa, Canada gathering research with scholars, government officials, and Inuit leaders. This report combines relevant literature with these engagements to understand the evolution of Arctic security. Aspects of security discussed include: the Northwest Passage, devolution of resources, Quebec’s Arctic policy, tourism, food security, biodiversity, homelessness, education, the Arctic Council, and China’s role in the Arctic. Each chapter provides specific policy options that together form a model for building capacity for communities.

More than a millennia after the earliest-known version was committed to text, fairy tales continue to occupy our bookshelves and airwaves. The current popularity of fairy tale-based television programs such as Grimm and Once Upon a Time offer continued proof that the appeal of these tales is not lost on 21st century audiences. Beginning with the rise of fairy tales in the ancient cultures of China and India, this paper will follow their journey through Asia, long before these tales reached their traditionally recognized European birthplace. In this examination of the multicultural variations of a single tale—the Cinderella story—we begin to understand just how these stories have evolved. By means of textual analysis, I will examine the familiar French literary version (Perrault) of Cinderella using V. Propp’s morphology of “function” and character, and semiotic theories advanced by Scholes (1982) and Berger (2000). I will then apply this structure to three television adaptations of the Cinderella story: the 1957 live-television broadcast of Rodgers and Hammerstein’s Cinderella, the 2006 pilot episode of ABC’s Ugly Betty, and—adding a global aspect—the 2007 Mexican production of La Fea más Bella. Likewise, I will examine the ways that the Cinderella tale has retained its relevance as it crossed cultures—a literary example of globalization through cultural flow—and how the sharing of its ideas has contributed to its historical persistence.

The reversible phosphorylation of proteins mediates a wide range of biological processes that range from signal transduction cascades to regulation of protein abundance. However, little is known about the mechanisms and evolution of phosphorylation networks. Despite the extraordinary advances in genome sequencing of many yeast species, evolutionary studies on the phosphoproteome of yeast species have been limited to the experimental analysis of phosphorylation in one species and theoretical analysis of the conservation of phospho-acceptor residues with other species. To properly study the evolutionary conservation phosphorylation in yeast, we are utilizing mass spectrometry to study and compare the phosphoproteome of 21 species of yeast, including representative species from each clade of the yeast phylogenetic tree. Most of these species have not been studied before by proteomics. This high-throughput phosphoproteomic study on the yeast species will contribute to the construction of phosphoproteome datasets, which can be exploited for comparative analysis of phosphorylation between the species. One of main aims is to identify phosphorylation sites that show a high degree of conservation across the 21 species of yeast. These highly conserved phosphorylation sites likely regulate the same functions across the different species, and these functions can be further studied and correlated to our understanding of the mechanistics of phosphorylation in key biological processes, as well as the diseases that occur when the signaling pathways that involve these sites are defective. The second aim of this project is to study the correlation between the conservation of the phosphoproteome with the conservation of the genome and transcriptome, which will expand our understanding of the evolution of phenotypic diversity. Finally, the large-scale dataset of the proteomes and phosphoproteomes holds a great potential for other types of computational analysis, and also serves as a foundational reference for future experiments.

Miller syndrome is a rare autosomal recessive disorder resulting from mutations in the DHODH gene. DHODH encodes the enzyme dihydroorotate dehydrogenase, which is involved in de novo pyrimidine biosynthesis. Clinical characteristics of Miller syndrome include craniofacial abnormalities, coloboma of the eyelids, cleft palate, and missing postaxial digits on the hands and feet. To broaden the spectrum of causal mutations, DNA samples obtained from two unrelated affected probands were Sanger sequenced to screen for mutations in DHOHD. In family 1, the affected individual was a compound heterozygote for a mutation in one of the canonical splice bases of intron 6-7 (c.820+1G>A), and a missense mutation in exon 8 (c.C1036T, p.R346W). DNA samples obtained from both parents of the affected proband were screened using Sanger sequencing and each parent was found to be heterozygous for one of the DHODH mutations. The c.C1036T mutation has been reported now in three families with Miller syndrome and functional studies have demonstrated a reduction of DHODH activity by 40%-70% in yeast with this mutation. No pathogenic mutations in DHODH were found in family 2. The next steps we will take include whole genome sequencing of the proband and parents in family 2 to determine if there are mutations in other genes that cause Miller syndrome. Our results mark the first report of a splice site mutation in a patient with Miller syndrome and further expand the spectrum of causative mutations in DHODH.

The first floral mutations ever documented, double flowers have been prized for centuries for their beauty. Double mutants known as ‘Shoaf’s Double’ and ‘Cameo’ are present in the species Thalictrum thalictroides, a member of the buttercup family. The purpose of this research is to determine the genetic mutation causing these phenotypes. We predicted that a mutation in a C-class floral organ identity gene would cause the homeotic transformation of stamens and carpels to petalloid sepals in this species. C-class genes are also involved in floral determinacy, the termination of growth in the flower meristem, which is why double flowers appear to have a second flower nested inside the first. As expected, the expression of the C-class gene AGAMOUS1 (AG1) was greatly reduced in our mutants. To pinpoint the mutation we first sequenced the coding region, the part of a gene that becomes a protein. Finding no changes from wild type I further sequenced the entire genomic locus. In AG1, the first intron is known to have regulatory function. I found evidence of the action of a DNA transposable element in both mutants. In “Shoaf’s Double” a Mutator element has inserted itself into the first intron of AG1, potentially disrupting its function. In “Cameo” there is a ‘footprint’ present in the same site, which indicates the same element may have jumped out, deleting a necessary section of the gene. These results show the presence of at least one active DNA transposon in this species, capable of causing a phenotype due to disruption of a regulatory region. This transposable element could potentially be induced to jump and create new mutant lines. Similar mutations could potentially underlie other popular double flower cultivars, such as those found in roses, camellias and carnations.

The ABC model of flower development explains the patterning of organs along the flower axis. Involving mostly MADS box genes, that partake in determining flora organ identity, this model has been the botanical counterpart to the Homeobox genes which participate in the morphogenesis of animals. The model predicts the production of the four floral organs sepals, petals, stamen and carpels, through various combination of the A, B, and C-class genes. The flowering plant species Thalictrum thalictroides, in the buttercup family Ranunculaceae, belongs to an interesting lineage that is sister to all other eudicots, including the model system Arabidopsis thaliana. T. thalictroides flowers consist of three types of organs: sepals, stamens and carpels, lacking petals. However, the sepals express a petaloid morphology, being large and white or pink. I will be using a forward genetics approach to study a horticultural mutant of T. thalictroides, ‘Betty Blake.’ Its phenotype consists of multiple whorls of non-petaloid (green) sepals and multiple whorls of carpels, resembling B-class gene mutants. We hypothesize that the reason for the lack of stamens, the extra carpels and non-petaloid sepals in ‘Betty Blake’ is a mutation in one or more of the B-class genes. The four B-class candidate genes belong to the MADS box gene family and function in petal and stamen identity. I will be sequencing and analyzing the entire genomic locus of 8 candidate genes, by means of basic molecular biology techniques. A mutation could cause a loss of B-class function potentially, resulting in a homeotic conversion from stamen to carpels and sepals. Molecular dissection of this mutant will contribute to understanding the degree of conservation of stamen identity genes across divergent flowering plants, and to test whether sub-functionalization in the B class gene lineage contributes to petaloidy of sepals.

Protein phosphorylation is a common regulatory mechanism carried out by the cell, as adding a phosphate group to a particular protein can switch its activity on or off.  Signaling pathways employ this control method to instigate series of phosphorylation events that elicit a particular cell response.  Our research involves extracting and characterizing the phosphoproteome, or the cell’s entire set of expressed phosphorylated proteins, in both yeast and mammalian cell models.  To generate lists of phosphoproteins present in these cell models, we use mass spectrometry, an analytic technique that produces characteristic spectra for individual phosphopeptides that are then matched to a library of known protein spectra through the use of computer algorithms.  In our preliminary results, we have generated large-scale data sets identifying thousands of phosphorylated proteins present in each species and cell type.  The goal of the first project, the yeast study, is to determine the degree of evolutionary conservation in phosphorylation events across 19 yeast species to learn about the basic principles of phosphoregulation.  The conservation of phosphorylation can also give insight into phosphorylation events in other species evolutionarily related to yeast, such as humans.  The second project, the mammalian cell study, examines the phosphoproteome of different breast cancer cell types in order to identify common phosphorylated proteins, from which we can deduce a molecular signature for breast cancer.  This signature can be used in future studies to design a universal protein inhibitor drug as an alternative anti-cancer therapy.  Additionally, by identifying the phosphoproteins exclusive to each cell type, we can uniquely characterize specific types of breast cancer.  Knowledge of the proteins active in one type of breast cancer may facilitate development of inhibitor drugs as a form of personalized medicine.

Aerospace vehicles, such as reusable spacecraft and hypersonic flight vehicles, require materials that can both provide high thermal resistance and high mechanical strength. Thermal insulation is required to protect the vehicle interior including occupants from the high heat of reentry and mechanical strength is required to withstand the variety of loads including the forces experienced during launch. In general, it is difficult to meet both these requirements at a high level since the normal way to increase thermal resistance of porous ceramics is to increase the porosity but this reduces strength. We are currently developing and investigating anisotropic porous ceramics that have the potential to optimally meet both these requirements. We are making the anisotropic porous ceramics from through a route called polymer derived ceramics (PDCs). The class of PDC’s that is being investigated is siloxanes, which decompose at high temperatures (~800^oC) into a SiOC ceramic. These materials have excellent high temperature resistance including creep and low thermal conductivity. Polymethylphenylsilsesquioxane (Waker H44) is first cross-linked and milled into a fine powder. The powder is then pyrolyzed to a SiOC ceramic that is then milled into a fine ceramic powder. A water-based slurry is made and poured into a mold that sits on a cold copper rod that is cooled in a liquid nitrogen bath. This causes ice crystals to form in the slurry which grow perpendicular to the copper rod. The frozen component is then freeze dried, causing the ice to sublime leaving a highly anisotropic porous structure. The thermal and mechanical properties will be measured in the longitudinal and transverse directions and the properties of these anisotropic porous microstructures will be compared to those of isotropic porous ceramics of similar porosity.

Malaria is a parasitic infection due to Protozoa Plasmodium. This is a severe global disease with 250 million annual cases leading to 1-2 million deaths. The most virulent, P. falciparum, is responsible for severe clinical malaria and death. An array of anti-malarial treatments exist today, however parasites evolve continuously to develop resistance even to the newest frontline anti-malarial drugs. Previous studies in the Rathod laboratory have demonstrated that drug resistance can be generated in the lab and that some drugs can be utilized to characterize Accelerated Resistance to Multiple Drugs (ARMD) parasites, such as the laboratory strain Dd2, and non-ARMD parasites, such as the laboratory strain HB3. In the current study, we are using a cyclopropyl carboxamide (GSK 2645947) to select for resistant parasites. Cyclopropyl carboxamides are a chemically novel class of antimalarial agents identified recently and they prevent the growth of P. falciparum in the early trophozoite stages of the erythrocytic Plasmodium cycle. This project focuses on determining the conditions for the development of resistance against GSK 2645947 with Dd2 and HB3 by conducting a series of selection experiments utilizing different concentrations of GSK 2645947 and starting parasites populations. Unlike previous conditions which indicate that the Dd2 strain acquires resistance at a significantly higher frequency than the HB3 stain; the data from this study suggests that both Dd2 and HB3 strains respond similarly to GSK 2645947. Through this study, we can further understand the behavior of resistant P. falciparum parasites. 

Breast cancer tumors are classified within different subtypes based on the expression of three types of cell surface receptor proteins.  These proteins connect the extracellular environment with cellular activities via signaling pathways.  To elicit cell responses, signaling pathways employ protein phosphorylation as a regulatory mechanism, as adding a phosphate group to a particular protein can switch its activity on or off.  However, normal signaling can go awry if mutations in signaling proteins lead the cell to believe its components are always phosphorylated and active.  Consequently, the entire signaling pathway functions abnormally, which can lead to uncontrolled cell growth characteristic of cancer.  Given its potential role as a molecular mechanism of disease, our research focuses on obtaining a global view of the phosphoproteome, or the cell’s entire set of expressed, phosphorylated proteins, of 10 breast cancer cell lines.  To generate lists of phosphoproteins present in these cell lines, we are concurrently extracting and analyzing cell line phosphopeptide samples via mass spectrometry, an analytic technique that produces characteristic spectra for individual phosphopeptides that are then matched to a library of known protein spectra through the use of computer algorithms.  In our preliminary results, we have generated large-scale data sets identifying thousands of phosphorylated proteins present in two cell lines and generated side-by-side comparisons of the proteins expressed in each line.   By identifying common phosphorylated proteins across all of the cell lines, our goal is to deduce a molecular signature for breast cancer.  This signature can be used in future studies to design a universal protein inhibitor drug as an alternative anti-cancer therapy.   By identifying the phosphoproteins exclusive to each cell type, we can uniquely characterize specific proteins active in one type of breast cancer which may facilitate development of inhibitor drugs as a form of personalized medicine.

Organizations are increasingly expected to publish policies communicating their perspectives on diversity, but how do these diversity messages affect the racial minorities who work there? The current research examines whether the two most common ideologies in diversity messages, colorblindness, which focuses on individual qualities and minimizes the importance of group differences, and multiculturalism, which emphasizes acknowledging and appreciating group differences, influence whether racial minorities interpret their experiences as due to discrimination. Asian American participants will imagine a scenario in which they work at a company that endorses either a colorblind or a multicultural ideology and are passed over for a promotion in favor of a less qualified White candidate. We expect that participants who are passed over for a promotion in an organization that promotes colorblindness, and therefore deemphasizes the importance of group memberships, will be less likely to interpret this treatment as discrimination those who are passed over in an organization that promotes multiculturalism, and therefore emphasizes the importance of group membership. This research demonstrates that the perspectives organizations take on diversity have implications beyond recruiting minorities and reducing bias; they can actually shape whether racial minorities perceive the same treatment as discriminatory.

Recent studies demonstrate that certain reproductive factors such as parity (defined as the number of completed pregnancies) are disparately associated with various pathologic subtypes of breast cancer. One factor, fetal microchimerism - the term for persistent child-origin cells in a woman’s circulation and tissues long after delivery - is generally deficient in women with unselected breast cancer and suggests a protective role. Here, we are testing the hypothesis that high-grade triple negative breast cancer (positive association with parity) will be distinctly associated with fetal microchimerism compared to low-grade luminal breast cancer (inversely associated with parity). Buffy coat specimens (n=450) were obtained from breast cancer patients and control participants aged 18-44 from the REACH project (Fred Hutchinson Cancer Research Center, PI Christopher Li). Using quantitative polymerase chain reaction, DNA extracts from these specimens were tested for the presence and concentration of Y chromosome sequence DYS14, a marker of male fetal microchimersim. In an interim analysis from the first 87 specimens, 33% (9/27) of women who developed luminal breast cancer tested positively for the presence of DYS14, as did 33% (10/30) of healthy controls. 47% (14/30) of women who developed triple negative breast cancer tested positively for the presence of DYS14. Preliminary results demonstrate a higher prevalence of fetal microchimerism in patients with triple negative breast cancer compared to control or luminal participants consistent with the original hypothesis. Additional samples will be tested. Fetal microchimerism testing may represent a novel non-invasive method to identify women with poor prognosis breast cancers.

Atherosclerotic cardiovascular disease is the leading cause of death in North America.  Hepatic lipase (HL) a liver enzyme that hydrolyzes lipoprotein triglyceride, plays a critical role in lipid metabolism and may influence the development of atherosclerosis.  Hepatic lipase may serve dual roles in the development of atherosclerosis: 1) HL may be pro-atherogenic by converting low-density lipoprotein (LDL) to small-dense LDL, causing build up of cholesterol in arteries. 2) HL may be anti-atherogenic by increasing the cholesterol-poor form of high-density lipoprotein (HDL) that removes cholesterol from the arteries, decreasing build up of cholesterol in arteries.  Previous studies have reported that elevated levels of human hepatic lipase (hHL) reduce the development of atherosclerosis.  However, those studies were done in transgenic mouse models with supra-physiologic levels of hHL and may not accurately reflect the role of physiologic levels of HL on atherosclerosis.  Therefore, we created a physiologic model of hHL expression to analyze the role of hHL in the development of atherosclerosis.  This “humanized” mouse model expresses hHL at physiologic levels in the liver.  We hypothesize that physiologic levels of HL will reduce the development of atherosclerosis compared to mice lacking HL.  To test this hypothesis we bred the transgenic hHL mice onto a low-density lipoprotein receptor knock out background (which is an established model for atherosclerosis).  Littermates with and without the hHL transgene were fed a high-fat, cholesterol enriched (“Western”) diet to accelerate atherosclerosis development, after which the aortas were harvested, dissected longitudinally, and pinned to expose the inner aortic walls for visualization.  Cholesterol buildup was stained and the ratios of atherosclerotic accumulation to total aortic surface area were quantitatively measured via Adobe Photoshop.  Results from this study will clarify the contribution of hHL to atherosclerosis development.  Ultimately, our results will guide the development of new treatments to prevent and treat atherosclerosis.

 Human aortic diseases such as aneurysms (abnormal dilation of the aorta) dissections (tears in the wall of the aorta) are often life-threatening. These diseases present significant challenges because: 1) their pathogenesis is not well understood; 2) they are difficult to diagnose, often presenting at an advanced, life-threatening stage; 3) they have limited treatment options; and 4) the treatments are all associated with major complications. Our work focuses on achieving a better understanding of the pathogenesis of aortic aneurysms and dissections, with a long-term goal of preventing or stabilizing these diseases. Signaling pathways initiated by transforming growth factor beta (TGF-β) in smooth muscle cells (SMC) of the aorta are essential for normal vascular development. Mouse embryos lacking SMC TGF-β signaling exhibit abnormal aortic structure, including dilation of the distal aorta. However, the role of SMC TGF-β signaling in maintaining the structural and functional integrity of the adult aorta is unclear. We use a transgenic mouse model to test the hypothesis that TGF-β signaling in adult aortic SMC preserves aortic health and prevents aortic aneurysms and dissections. With this model we can delete a gene that is critical for TGF-β signaling specifically in SMC of adult mice, and thereby discover the role of SMC TGF-β signaling in the regulation of SMC gene expression and aortic structure. We expect to find abnormal gene expression and aortic structure in adult mice with loss of SMC TGF-β signaling. Our study may uncover signaling pathways and gene expression patterns that maintain aortic health. These pathways may eventually be exploited to develop therapies that prevent aortic aneurysms and dissections.

Income inequality and level of education affects countries across the world. Within the last few years, Thailand’s income inequality seems to have worsened, as is seen from many political conflicts created from the significant gap between the rich and poor.  From the World Bank Poverty Analysis, there has been a dramatic decline of poverty in Thailand since early 1960’s.   However, the decline in poverty was not uniform across regions of the country; poverty is more concentrated in the rural areas.   Therefore, the increase in inequality was also not uniform across the country; the wider income differentials between households in different locations accounted for the increase in overall income inequality.  This means educational attainment plays an important role for labor to make a transition from the old sector to the new sector, and thus is one of the determined factors for income inequality.  In this paper, I will examine the impact of education and skills owned by individual on wage and income distribution of Thailand.  First, I will explain about the previous research on the relationship between education, skills, and wage. Then, I will explain about the data set and the methodology that will be used. Lastly, I will present and explain the result using Mincer's wage regression analysis and give the conclusion.

Quantum dots (QDs) are the precursor for numerous burgeoning technologies, including more efficient solar panels and high definition LED displays. QDs are small, soluble crystallites of a semiconductor material that have unique qualities since their electrons are confined in all three dimensions in a region of space smaller than the de Broglie wavelength of their electrons. This allows the electrons to occupy spectrally sharp energy levels like an element or a molecule. Their electronic properties can be tuned as a function of their size. In our lab, indium phosphide QDs are prepared under an inert atmosphere of dinitrogen by hot injection of a phosphine precursor into an indium salt and fatty acid solution. Taking aliquots of the reaction mixture at different time intervals during QD growth allows us to chart the rate of particle evolution and provides information about particle size and uniformity. Indium phosphide is a member of the III-V semiconductor class, meaning they are made from elements from column three and column five of the periodic table, and have desirable properties like direct band gaps which allow these materials to efficiently absorb and emit light as well as faster carrier mobility than II-VI quantum dots. The synthesis of III-V QDs has not allowed for size- uniformity or tunability to be achieved because of the uncontrolled reactivity of the precursors, in particular the group V precursors. Our group has recently uncovered an important acid-catalyzed pathway leading to phosphine speciation during indium phosphide QD growth. My project focuses on addressing this issue by incorporating new, more stable precursors and chelating capping agents to better stabilize the reaction products and intermediates, which would be crucial in controlling the formation and therefore the properties of the resulting quantum dots.

Chitin is the second most abundant polysaccharide extracted from the cuticles of insects and crustaceans. Chitin is known for its biocompatibility and superior mechanical strength. Silk fibroin is produced by the Bombyx mori silkworm and is known for its biocompatibility and superior toughness. Composites of chitin and silk fibroin would possess each biomaterial's unmatched mechanical strength and toughness, making them ideal candidates for biomedical applications requiring such mechanical properties. Here, squid pen β-chitin and Bombyx mori silkworm cocoon silk were blended in Hexafluoroisopropanol (HFIP) solution in specified ratios to synthesize the nanocomposites. As a result, chitin/silk hybrid nanocomposite thin films were produced to test the mechanical properties. Studies of both X-Ray Diffraction (XRD) and Fourier Transform-Infrared (FTIR) Spectroscopy revealed a successful effective interaction between the chitin nanofibers and the silk proteins matrix, which was most likely caused by hydrogen bonding. Results of the self-assembled chitin nanofibers embedded in the silk matrix showed a noticeable enhancement in mechanical properties. The tensile strength, flexibility, and toughness of the biomaterial nanocomposites were enhanced compared to just pure chitin or pure silk fibroin. Due to the improvement in mechanical properties, these chitin/silk engineered nanocomposites can be utilized in biomedical applications such as hybrid scaffolds for bone tissue engineering or microneedles to serve as a new methodology for drug delivery systems.

In the United States prostate cancer (PCa) is one of the most commonly diagnosed cancers and estimated to affect 239,000 men in 2013. Although few prognostic biomarkers are currently used in the clinical setting, biomarkers that predict the risk of disease aggressiveness leading to prostate specific antigen (PSA) failure after prostatectomy may assist clinicians in selecting adjuvant therapies following prostatectomy. In studies utilizing co-registered pre-operative imaging data with post-operative pathology data, validated prognostic biomarkers may also be highly useful as “gold standards” against which to train imaging methods to assess disease aggressiveness pre-operatively. We previously identified 33 potentially prognostic biomarkers from the analysis of multiple gene expression datasets and current literature. Using tissue microarrays containing PCa tissue from 170 prostatectomy specimens from men with detailed PSA and follow up data, we quantified immunohistochemical (IHC) staining for these markers within selective tissue sub-regions (malignant epithelium) and identified 16 of the 33 biomarkers which were associated with shorter time to PSA failure. While our aim is to use validated biomarkers to pre-operatively train in vivo imaging methods, current imaging capabilities have lower resolution than digital histology and it is unclear whether biomarker expression in total tumor areas (encompassing malignant epithelium, benign epithelium, stroma, and other tissue structures) which are resolvable by imaging methods will also be prognostic. In this study, we have re-evaluated our list of 16 strong candidate biomarkers to determine if IHC expression within total tumor areas are associated with PCa aggressiveness (PSA failure following prostatectomy) using our TMA cohort.

Our 800,000-year climate record is dependent primarily on data obtained from ice cores. Analyzing and dating the ice, gas, and sediment in these cores allows us to construct a remarkably accurate historical record of Earth's climate and atmosphere. However, the dating and chronology of the ice record is not as exact as we would like it to be, especially deeper in the ice. Our ability to date ice cores with accuracy depends on our understanding the evolution of glacial firn, fallen snow that gradually compacts into ice. Researchers have developed many different models of firn evolution. The aim of this project is to run these models against each other under the same boundary conditions, so that we may compare their responses and determine the strengths of each model. Participants have submitted their model output and our results have been returned to them. A second inter-comparison will be organized to address issues brought up by our initial results. These comparisons will improve future efforts in firn-modeling, ultimately leading to a better understanding of our climate record.

Pollination syndromes refer to suites of floral traits that influence biotic or abiotic vectors transporting pollen from one flower to another. These traits include flower color, position, shape, size, scent and reward. Scent is a major component of pollination, as the volatile organic compounds (VOCs) that compose “scent” often attract pollinators or deter predators. The genus Thalictrum in the Ranunculaceae (buttercup family) possesses both insect- and wind-pollinated species, enabling comparisons of the role of scent in floral diversification among recently diverged taxa with distinct pollination syndromes. To characterize floral scent, we identified and compared the bouquet of VOCs emitted by insect- and wind-pollination species, as well as by floral vs. vegetative tissue. Focusing on twelve species representative of the two pollination syndromes and spanning the Thalictrum phylogeny, we identified 8 primary compounds of interest. These compounds are known to be chemical communicators for various insects, including bees and syrphid flies, reported to visit Thalictrum. The overall purpose of this project is to determine the differences in scent emissions between species in an evolutionary context, and identify the key volatiles involved in pollination syndrome variation. This will further illuminate our understanding of the biochemical and, ultimately, the genetic basis of these starkly different pollination syndromes. In addition, the variation in distribution of VOCs across species will also be used to test implications of patterns of compound development and reuse during evolution.

The distribution of temperature and precipitation on our planet (i.e. our climate), affects plant growth, animal habitats, and the livability of Earth's varied regions. In order to predict future climate we need to know about our past climate. This is important to better understand how temperature and weather conditions change when the radiative forcing (e.g. CO2 greenhouse effect) on our atmosphere increases. The best way to predict these changes is researching past radiative forcing increases and how these events impacted Earth’s climate. Some details of our past climate are discovered by analyzing polar ice and the gas bubbles trapped within. Firn is fallen snow that compacts and eventually turns into glacial ice. During this process gas can move relatively freely throughout the firn. When the firn densifies enough to block the air passageways, young gases are trapped in significantly older ice. This work is building a web-based community firn densification model that allows the user to accurately determine the difference between the age of a gas sample and the age of the ice surrounding it. Our transient model determines this delta age more accurately than current steady-state models by accounting for changing conditions as the firn turns into ice, instead of assuming conditions remain static throughout the firn evolution. This model is open-source, and written using the Python programming language, along with the NumPy library, allowing the model to be free and usable by anyone. Because the model is modular, users can easily change it to fit specific conditions or to incorporate different physical processes. Our goal is to provide a model that is simple to use, freely available, and helpful for developing a more accurate understanding of our past climate.