Tryptophan is one of the few amino acids that is intrinsically photoluminescent. This is because its side chain consists of indole. Indole’s photoluminescence has both fluorescence (emits for nanoseconds) and phosphorescence (emits for microseconds). Fluorescence emission comes from a singlet to singlet transition, while phosphorescence from a forbidden triplet to singlet transition. Taking advantage of tryptophan’s intrinsic emission, we can use it as a label-free probe for protein dynamics. For some of these dynamics, such as myosin binding to actin, the fluorescence lifetime of nanoseconds is too fast to monitor changes. The phosphorescence lifetime is much better suited to monitor these changes of large biomolecule interactions. Before any binding studies are developed, we have characterized the basic properties of indole’s phosphorescent properties. We began by embedding indole (as well as 5 – bromoindole) in a polymer matrix (PVA) to immobilize and thus increase the phosphorescence at room temperature. We discovered that using a longer wavelength of excitation (405 nm instead of 290 nm) we excite directly from the singlet state to the triplet state of indole, a typically forbidden process. This populates the triplet state without any transitions to the singlet state. This allows the polarization of phosphorescence emission to be preserved, and anisotropy measurements can be used to monitor biomolecular processes.

In a virus study, the inoculum dose is the initial amount of virus used. It is correlated to the initial
amount of cells that become infected at the start of the study and thereby also correlated with the
amount of virus that will be produced by infected cells at the beginning of that study. Those virus spread
through a body in two known ways: cell free transmission and cell to cell transmission. While previous
research has investigated viruses based on free cell transmission, few models have incorporated cell to
cell transmission leading to unclear results and bias to certain variables. This research accounts for both
modes of transmission, using an agent-based framework, and varies the initial amount of virus, to
understand how inoculum dose affects the two transmission modes. Utilizing parallel processing, the
model represents virus infection and spread in a two-dimensional layer of cells in order to generate total
virus over time graphs for corresponding initial amount of virus. This project demonstrates how a
combination of agent-based models and parallel processing can allow researchers to perform the rapid
and large simulations necessary for viral dynamics research efficiently and affordably.

In order to calculate the ground and excited states of a perturbed harmonic oscillator, we use computer codes developed from the results of coupled cluster techniques. More specifically, we have implemented a diagrammatic approach in order to efficiently derive cluster amplitude and energy equations, along with iterative Bogoliubov transformations in order to improve the accuracy of computed energies. Such Bogoliubov transformations improve the zeroth order Hamiltonian, which is shown for a quadratic and quartic perturbation. These results are then compared to exact results obtained from numerical integration of the Schrödinger equation, though we note that numerical integration cannot be performed for more complex systems of coupled harmonic oscillators under perturbation. Explicit coupled cluster equations are also presented for such coupled systems subjected to similar perturbations.

DNA biomarkers are of growing significance for the personalized medicine, with applications including diagnosis, prognosis, and determination of targeted therapies. However, even unicellular organisms can represent a heterogenous system on a molecular level. Improving the detection limits for low DNA concentrations will allow for better decision making, e.g., in clinical medicine, research endeavors, and human identification in forensic investigations where frequently only a minute amount of evidence material is available.
The first step for DNA collection is typically collecting specimen by specialized medical swabs. Medical swabs come in all different materials, shapes and sizes. They are not the same, but they are often used interchangeably. For DNA testing swabs can be used in buccal and surface swabbing for DNA. Then the swab with DNA on it is sent for analysis. A common analysis technique is using fluorescence. But what if the swab itself has some fluorescence? Do different types of swabs have different fluorescence? We want to test the inherent fluorescence of a variety of different types and brands of medical swabs to determine the kind with the best properties for highly sensitive DNA detection. If the swab’s fluorescence is short-lived, we expect that we will be able to separate out the swab’s signal from the DNA’s signal by using long-lived dyes and our novel multipulse excitation scheme.

With the advent of graphene, there has been an interest in utilizing this material and its derivative, graphene oxide (GO) for novel applications in nanodevices such as bio and gas sensors, solid state supercapacitors and solar cells. Although GO exhibits lower conductivity and structural stability, it possesses an energy band gap that enables fluorescence emission in the visible/near infrared leading to a plethora of optoelectronic applications. In order to allow fine-tuning of its optical properties in the device geometry, new physical techniques are required that unlike existing chemical approaches yield substantial alteration of GO structure. Such desired new technique is one that is electronically-controlled and lead to reversible changes in GO optoelectronic properties. In this work, we for the first time investigate the methods to controllably alter the optical response of GO with the electric field and provide theoretical modelling of the electric field-induced changes. Field-dependent GO emission is studied in bulk GO/PVP films with up to 6% reversible decrease under 1.6 V/µm electric fields. On an individual flake level, a more substantial over 50% quenching is achieved for select GO flakes in polymeric matrix between interdigitated microelectrodes subject to two orders of magnitude higher fields. This effect is modelled on a single exciton level by utilizing WKB approximation for electron escape form the exciton potential well. In an aqueous suspension at low fields GO flakes exhibit electrophoretic migration indicating a degree of charge separation and a possibility of manipulating GO materials on a single-flake level to assemble electric field-controlled microelectronics. As a result of this work, we suggest the potential of varying the optical and electronic properties of GO via the electric field for the advancement and control over its optoelectronic device applications.

Star clusters are key age-dateable tracers of the chemical history of the Milky Way. Star clusters can provide significant constraints on galaxy chemical evolution models. The large discrepancies between different small studies limit the accuracy of these constraints, so a large uniform study is needed. To create a large uniform sample, we observed stars in 63 clusters with the same telescope. We then determined the chemical makeup of these stars using a machine learning tool called The Cannon. Using this sample, we examine the change in chemical abundance over the radius of our galaxy.

Nano- and microcrystalline ZnO is a low-cost material, employed in many applications due to its optoelectronic, structural and chemical properties as well as a great variety of synthesis methods. Among these applications, antibacterial action of ZnO is a budding field of interdisciplinary research. Despite numerous studies of this antibacterial action, the physical and chemical mechanisms behind it are still largely not understood. In particular, the influence of the crystal surface morphology and surface-surface interactions between the bacteria and ZnO are largely unknown. Hexagonal (wurtzite) ZnO crystals terminate with three different types of crystallographic surfaces: charged polar hexagonal (Zn or O), electrically neutral nonpolar rectangular and partially polar pyramidal slanted. In our studies we employ a hydrothermal growth procedure to synthesize nanocrystals and microcrystals of ZnO with tunable morphology to investigate the influence of surface types on interactions with bacteria as well as surface charge dynamics. To quantify the antibacterial action we employ minimum inhibitory concentration (MIC) assays of staphylococcus aureus with hydrothermally-grown ZnO microcrystals. Scanning electron microscopy (SEM) is used to characterize the morphology of the as-grown ZnO specimens as well as the organization of these particles after their interactions with bacteria. To characterize electronic structure and dominant charge transport mechanisms at ZnO surfaces we performed photovoltage (SPV) experiments. Our results confirm that antibacterial action is a result of ZnO surface interactions with extracellular material, whereas internalization of ZnO particles (happening in the case of nanoscale ZnO) is not necessary for inhibition. We also report that the electronic transitions at the surface of the ZnO particles are consistent the theoretically predicted electronic structure of ZnO, with the spectral signatures of surface states which could be the source of the antimicrobial action.

Reportedly, hydrophobic surfaces of polysulfone (PSu) thin films become hydrophilic following exposure to UV radiation and it can affect PSu novel applications in microfluidics and biophysics. Fundamental mechanisms behind this effect remain unknown. To elucidate them, in our work we study surface charge transport employing surface photovoltage (SPV) on thin PSu polysulfone films spin-cast on silicon substrates. Since exposure of PSu even to an ambient UV light could affect the surface properties we ran SPV spectroscopy as well as SPV transient experiments on both as-received samples fabricated in darkness and UV-irradiated films of varying and controllable thicknesses. We report on the comparison of the SPV response in the as-deposited and UV-irradiated polysulfone samples.

Modern astronomical catalogs consist of up to billions of stars and measure various properties of these objects. There have been recent data releases from two of these surveys, GAIA which measures positions and distances, and APOGEE which measures radial velocities and stellar physical properties. By combining these datasets we have the full 6D phase space information for each star and can compute orbital characteristics and kinematics properties. APOGEE targeted specific stellar populations in our Milky Way and determined some of their physical properties. By cross matching with GAIA, we are able to fully describe the orbits of these populations and look for potential new members that have the same physical and kinematic properties but are not located in the immediate vicinity. We will present kinematic properties of the full cross matched dataset as well as information on the targeted stellar populations of the Milky Way.

Metal nanoparticles on a substrate have gained significant attention in recent years as novel systems for new generations of catalysts. Among other metals, iron attracts constant attention due to its low cost. Iron possess either the body-centered cubic (bcc) or the face-centered cubic (fcc) structure. Up to 917 °C, iron exists in its α-form (α-Fe) with the thermodynamically bcc lattice. At 917 °C, α-Fe transforms into the fcc lattice, and this allotrope is termed as γ-iron (γ-Fe) (austenite) with diamagnetic properties. According to the iron-carbon phase diagram, γ-Fe can incorporate up to 2.03% carbon. Lowering the temperature below 917 °C, carbon atoms diffuse out of the structure, and γ-Fe turns back to α-Fe. Up to now, γ-Fe could not be stabilized without such impurities as Mn, Cr, Ni at room temperature. We have obtained of iron nanoparticles with the face-centered cubic structure with diameters of up to 200 nm without impurities on the substrate of graphene oxide by thermal annealing in an inert gas. In our work we show that phases formation of iron depends on the temperature of annealing. At the annealing temperature from 300 ºC through 600 ºC only iron oxides are formed. We established the unexpected formation of the γ-phase already at 700°C by X-Ray diffraction and Mössbauer spectroscopy. These methods clearly identify the stability of the γ-phase at room temperature. The rather low transition temperature of α-Fe to γ-Fe already starting at 700 °C suggests that the mechanism for the transformation is different from that observed for bulk iron. The maximum γ-iron nanoparticles content on the substrate of graphene oxide was fixed at an annealing temperature of 950 °C.

Past research suggests that conditions of scarcity increase the intensity of female same-sex competition. As such, cues to resource scarcity (vs. abundance) might lead women to perceive greater competitive tendencies in their same- (vs. opposite-) sex peers. This prediction was examined across three studies. Across all studies, the opposite pattern of results emerged. Study 1 demonstrated that women perceived higher levels of competitive interactions to occur amongst female (as compared to male and mixed-sex) target groups in environments where resources were abundant. In Study 2, women who perceived resources to be widely available evaluated same-sex others as more competitive than opposite-sex others. Finally, Study 3 provided evidence that women who are led to believe that resources are abundant reported expecting more competitive behavior from their same- (vs. opposite-) sex peers. These results suggest that resource abundance might foster greater competition among women, which has implications for women’s workplace and interpersonal relationships.

Previous research in our lab has found that extrapolating from known to unknown attributes about a group can cause individuals to adopt more extreme attitudes (i.e., become self-radicalized) toward the group. This has been found to be particularly true when people extrapolate from known to unknown attributes about people who agree and disagree with them about a social issue. The current experiment aimed to extend our understanding of these processes by determining whether extrapolating about people who agree and disagree with the extrapolator about a social issue would also report greater self-radicalization toward the social issue in general. Our results revealed that participants who initially opposed kneeling during the national anthem reported more negative attitudes toward kneeling during the national anthem after extrapolating than did participants in the control condition. Conversely, participants who initially favored kneeling during the anthem reported more positive post-manipulation attitudes after extrapolating than did participants in the control condition. These results extend the understanding by which attitudes can become more extreme in the absence of new information.

Few studies have directly evaluated the assumption that equivalence-based instruction (EBI) establishes stimulus classes with greater efficiency than complete instruction (CI) of all possible stimulus relations within each class. The present study was identical to a previous study that failed to support this assumption, except that in the present study, mastery assessment was designed to favor the EBI condition over the CI condition. Forty-eight undergraduate students were assigned to one of four groups that received instruction on arbitrary stimulus relations. The EBI-CI group received EBI in Phase 1 and CI in Phase 2, and vice versa for the CI-EBI group. The EBI-EBI and CI-CI group received EBI and CI in both phases, respectively. In Phase 1, EBI-first groups received training on AB and BC relations and CI-first groups received training with all possible relations. After achieving mastery criterion, the ABC test included all possible trial types. In Phase 2, all groups received training to (a) add a fourth stimulus (D), and (b) add a fifth stimulus (E) to the class, using either EBI or CI. EBI took significantly fewer trials to complete than CI in both phases, but EBI in Phase 1 did not facilitate EBI in Phase 2. The results suggest the EBI arrangement used in this study may be more efficient than CI only because it permits faster learning assessment.

Hypoplastic Left Heart Syndrome
Alexis Damm, PA-S2
A.T. Still University: Arizona School of Health Sciences

Background: Hypoplastic left heart syndrome is a congenital heart disease that involves malformation of the left side of the heart. This etiology requires intervention after birth, and it effects 1 in 4,344 babies born in the United States (CDC, n.d.).

Clinical Case: A 4 year old male diagnosed with hypoplastic left heart syndrome prior to birth. This case study will focus on the history, diagnosis and treatment of a complication of hypoplastic left heart syndrome. The unique factors that influence this patient’s course of treatment will be highlighted in order for the disease to be better understood.

Conclusion: This clinical scenario showcases the importance of understanding birth defects, associated complications, and highlights the positive outcomes of proper pediatric care.

Reference: Center for Disease Control and Prevention. (n.d.). Congenital Heart Defects - Facts about Hypoplastic Left Heart Syndrome | CDC. Retrieved from https://www.cdc.gov/ncbddd/heartdefects/hlhs.html

Recently, terrestrial shoreline spiders have been proposed as biosentinels of bioaccumulative aquatic contaminants such as mercury (Hg). Terrestrial shoreline spiders become contaminated with Hg when they feed on Hg-contaminated emergent aquatic insects. Although the effect of body size on contaminant bioaccumulation in other biosentinels, such as fish, has been thoroughly examined, there has been much less research on the effect of body size on concentrations of Hg in shoreline spiders. In this study, we determined the effect of body size on Hg concentrations in six taxa of shoreline spiders belonging to four families (orb-weavers, [Araneidae], long-jawed orb-weavers, [Tetragnathidae: Tetragnatha spp.], jumping spiders [Salticidae] and wolf spiders [Lycosidae: Pardosa spp., Rabidosa spp. and Schizocosa spp.]. We collected 683 spiders during the day using sweep nets or by hand at night on May 14, June 5, 11, 20 and July 6, 2018 from 14 human-made ponds at the Lyndon B. Johnson National Grasslands, Texas, USA. Average total Hg (THg) concentrations (mean ± SE) ranged from 63 ± 4.0 ng/g to 246 ± 20.1 in Araneidae and Schizocosa spp., respectively, and were significantly different between spider taxa. We measured tibia + patella length on the first leg as a proxy for body size and found that spider THg concentration increased significantly with spider body size for Araneidae, Tetragnatha spp., Salticidae and Pardosa spp. The percent of variation in THg concentration explained by spider body size ranged from 16% to 40% for Pardosa spp. and Salticidae, respectively. This study indicates that Hg accumulation in shoreline spiders differ between spider taxa and within taxa by spider size. We recommend that future studies of Hg in shoreline spiders include assessment of spider size.

Thyroid disrupting compounds (TDCs) are known to interfere with normal thyroid hormone (TH) signaling. During embryonic and juvenile development, thyroid hormones modulate a variety of biological processes such as neurogenesis and the growth of the skeletal and muscular systems. Therefore, the majority of research on early life-stage (ELS) thyroid disruption has focused on its effects on growth and development. However, recent research has shown that ELS TDC exposure can also have adverse effects on reproduction later in life. Specifically, fathead minnows exposed to propylthiouracil (PTU), an anti-thyroid drug known to inhibit the synthesis of thyroxine (T4), during early development (from hatch through 42 days post hatch) experienced a 50% reduction in fecundity relative to controls. Interestingly, this statistically significant reduction in fecundity occurred when males, but not females, were subjected to ELS PTU exposures. After ruling out the possibility that ELS thyroid disruption altered testicular function, it was hypothesized that the observed reductions in fecundity resulted from changes in male reproductive behavior. To investigate the potential for and mechanism underlying PTU-induced alterations in male behavior, brains of PTU-exposed and control males were collected immediately after exposure for transcriptomic analysis. Of the genes that were found to be differentially expressed between the brains of PTU-exposed and control males, several were associated with axon guidance, behavior, and sex steroid signaling. Specifically, PTU-exposed males experienced significant reductions in the expression of serotonin receptor, fibronectin, estrogen receptor alpha, and aromatase. Given the known role of these genes in development and sexual differentiation of the male brain, these results provide evidence supporting the hypothesis that ELS chemically-induced hypothyroidism leads to altered neurogenesis and subsequent alterations in behavior. Overall, the results of this study may help link transcriptomic alterations in the brain to alterations in reproductive behavior, which has important population-level consequences.

Alterations in neurological development and/or vision have been noted after exposures to a variety of environmental contaminants, including heavy metals, pesticides, pharmaceuticals, and estrogens. Despite the growing interest in assessing the neurotoxicity of toxicants, routine toxicity testing methods do not currently include the assessment of endpoints capable of predicting adverse impacts on neurological development. A toxicity test featuring embryonic fathead minnows - the fish embryo toxicity (FET) test - was recently developed; however, it does not include neurological-related endpoints. Development of such endpoints would expand the utility of the FET test and allow for the assessment of neurological teratogens. Previous studies have identified embryonic eye size as a potential FET test endpoint, and though there is limited evidence suggesting that these alterations are indicative of altered neurological development, studies validating the link between eye size and organism fitness are needed. The overarching goal of this project is to investigate whether reduced embryonic eye size at the conclusion of the FET test is predicative of altered vision or neurological function in larval fathead minnows. But first, assays for assessing vision and neurological function in larval fathead minnows must be developed and/or validated. Therefore, the objective of the present study was to validate methods to assess vision/neurological function in larval fathead minnows. Three assays were developed: the optomotor response assay, a feeding assay, and the c-start assay. The ability of these assays to identify alterations in the neurological function of larval fathead minnows was assessed by exposing larvae to three doses of the known neurotoxicant chlorpyrifos for 5 or 12 d. These results will be utilized in future studies investigating whether reductions in embryonic eye size are predictive of sublethal adverse effects and can also be utilized by other researchers interested in assessing vision/neurological function in larval fathead minnows.

Texas horned lizards Phrynosoma cornutum are a threatened species in the state of Texas, due to population declines and extinctions, especially in the eastern part of their range. Texas horned lizards are still found in small towns in south Texas and can reach densities that are much higher (~50 lizards/ha) than in natural areas (~4-10 lizards/ha). We used models of Texas horned lizards to test whether predation levels might be lower in two south Texas towns than on a ranch that was located in south Texas. We constructed Texas horned lizard models from urethane foam, a material that is ideal for preserving marks (bites and pecks) left behind by predators. Models (n = 126) were left in the field for a period of 9 days in each location and marks left behind by predators were categorized accordingly. We conducted this experiment in June and again in August 2018. We found significantly less attempted predation events in the towns (n = 1 predation attempt) compared to the ranch (n = 60) and no differences between months. Anecdotal observations over the past 6 years also support a lack of many horned lizard predators in the towns. Our results suggest that Texas horned lizards may be under heavy predation pressure in natural environments and that lizards living in urban areas may be escaping some of this pressure leading to higher than normal lizard densities in some small Texas towns.

Most of the literature on the basic ecology of Texas Horned Lizards cites "cryptic color pattern" as the first line of defense against predation in this taxon, and yet the degree to which horned lizards actually color-match their backgrounds has never been quantified. Texas zoos and state wildlife agencies are releasing captive-bred hatchlings and translocated adults to parts of their former range; however, the new populations are not self-sustaining, with the majority of releases lost to predation. Background color-matching has not been quantified for these reintroduction efforts but may be important to take into account when moving lizards into a new habitat where predation may be higher if they are not closely color-matched to the local soils. I quantify background color-matching in this taxon across its known range in the United States and in Mexico from in situ photos taken, as found, in the wild. I also present background color-matching variation and trends both within and between phenotypically and genetically diverse populations and ask whether lizards more closely match their local soil colors than soils from other areas. Finally, I suggest a method for zoos and wildlife agencies to score coloration in their captive populations of lizards, thus possibly enabling these institutions to objectively take into account color-matching a priori as an applied conservation strategy to potentially increase the survival of reintroduced Texas Horned Lizards.

Indigo Buntings (Passerina cyanea) and Painted Buntings (Passerina ciris) are closely related songbirds in the family Cardinalidae, found to co-exist in areas where ranges overlap. However, though both species share similarities in morphology, diet and preferred habitat characteristics, there is little quantitative data accumulated about the Painted Bunting and many aspects of its life history remain unclear. North American Breeding Bird Surveys have shown a significant decline in Painted Bunting population numbers across their ranges—a decline that has resulted in its designation of a Species of Special Concern by Partners in Flight. Proposed reasons for the decline include habitat destruction, sensitivity to disturbance and factors associated with decreased success in breeding. Within the Great Trinity Forest, the Indigo and Painted bunting’s breeding grounds overlap. The Great Trinity Forest is a large urban forest surrounded by the city limits of Dallas, TX containing a variety of disturbance factors characteristically associated with a highly urbanized area: poor habitat, invasive species, and increased noise and light. Sensitive species, such as the Painted Bunting, are typically found to avoid areas of disturbance. Data collected May-July 2018 shows presence/absence of both species within 140, 5 ha plots spanning the forest. Additional disturbance data was collected, including noise levels (db), invasive wild hog activity and percent impervious surface both within and surrounding each study site. Analysis of this data will aid in discovering how these species distribute themselves in relation to disturbance factors, urbanization and each other. Results will further serve to assist in future conservation efforts and increased life history knowledge of the painted bunting. It is predicted that disturbance factors within the Great Trinity Forest have a significant effect on Painted Bunting presence/absence while they have no significant effect on the Indigo Bunting.

Red-winged blackbirds (Agelaius phoeniceus) are found throughout North America, often nesting in cattails in ponds and wetlands. Diet studies have revealed that adults can feed their nestlings both emergent aquatic insects like odonates and terrestrial insects like lepidopteran larvae. Because emergent aquatic insects can be contaminated with high amounts of methyl mercury (MeHg), it has been hypothesized that nestlings fed high amount of odonates would be contaminated with levels of MeHg that are hazardous to their health. There have been no of studies of MeHg contamination of nestling Red-winged blackbirds and their diet. The objective of our study was to measure the concentration of MeHg in blood of nestling Red-winged blackbird and to estimate the proportion of emergent aquatic insects and terrestrial insects in their diet. We conducted a study of Red-winged blackbird nestlings at 20 ponds at the Eagle Mountain Fish Hatchery, Fort Worth, Texas. The ponds are contaminated with Hg from the atmosphere. Previous studies at the Hatchery have demonstrated that emergent aquatic insects such as odonates have high concentrations of MeHg while terrestrial insects on the pond shorelines have low concentrations of MeHg. Red-winged blackbirds nested in cattails in the ponds from April 9 to July 30 2017. We collected 424 blood samples from 243 nestlings from 88 nests (1-2 samples from 1-4 nestlings per nest). We analyzed the blood for MeHg, and analyzed 202 of the blood samples (1-2 blood samples from 1 per nest) for nitrogen stable isotopes. Methyl mercury was detected in nestling blood suggesting that Red-winged blackbird nestlings were fed emergent aquatic insects. However, concentrations of MeHg in nestling blood were low (mean of 0.020 ug/g ww) and below the risk threshold. Methyl mercury concentrations and nitrogen stable isotope ratios for Red-winged blackbird nestlings suggest that terrestrial insects composed a high proportion of their diets. Our study suggests that Red-winged blackbird nestlings may not be at risk of MeHg contamination when terrestrial organisms dominate their diet.

Floral herbivory (florivory) can have direct effects on both female and male reproductive output. Damage to flower parts such as petals and anthers can also have potential indirect effects by altering floral attractiveness to pollinators. Because carnivorous plants live in nutrient-poor environments and have slow growth rates, these plants may be at increased risk of negative effects of florivory. However, there has been no study to investigate florivory in carnivorous plants. We conducted a two-year field study on an east-central Texas population of the carnivorous pitcher plant Sarracenia alata and its specialist herbivore Exyra semicrocea. Populations were surveyed for number of flowers attacked, and the mass of floral components was compared between attacked and unattacked flowers. In 2017, a mean of 65% of flowers were attacked at the end of the flowering season. Based on mass before dehiscence, the mass of anthers after florivory was 49.5% of unattacked anthers. There were no significant differences in the masses of other floral structures at the end of the season. In 2018, 38% of flowers surveyed were attacked. The mass of attacked ovaries was 47% that of unattacked, the mass of sepals and petals combined was 62.5% that of unattacked, and the stigma/style complex was 51.0% that of unattacked. The mass of attacked anthers before dehiscence was 18.7% that of unattacked anthers. This study shows that there was annual variation in both the proportion of flowers attacked in the population, and the extent of damage seen in floral structures. Future studies should examine the effects of florivory on pollen limitation, pollinator behavior, and recruitment in Sarracenia alata.

It is extremely important in our age to look for alternative, more environmentally favorable energy sources. The Sun is a largely unused and widely available energy source to power human industry which can be utilized in different ways. Photovoltaic cells directly convert solar energy to electricity but only provide power when illuminated. Supplying solar-sourced energy during night hours and inclement weather requires conversion to another form, for instance into chemical fuel by means of water splitting into oxygen and hydrogen. This strategy, inspired by natural photosynthesis, is currently a promising and actively researched approach. However, achieving a high energy conversion efficiency, which is essential for industrial implantation of the method, remains a primary goal.
A Dye-Sensitized Photoelectrochemical Solar Cell (DSPEC) is specifically designed for using solar energy to generate hydrogen from water. We are pursuing the formation of photoanodes with polymer surface coatings prepared by electropolymerization. The polymer interfaces are designed to promote directional electron transfer at the interface, thereby resulting in a better solar energy conversion efficiency. The structure of the surface polymer enables the incorporation of catalyst units to the interface. To this end, we have prepared several novel iridium-oxide nanoparticle suspensions, using two different synthetic methods, to serve as the water-oxidation catalysts in our system. During the synthesis, the nanoparticles are functionalized with specific capping groups that contain terminal double bonds, through which they can be incorporated to the surface polymer electrochemically. Using acrylic acid and acrylamide as small molecule precursors, electro-polymer coatings have been prepared on FTO (fluorine-doped tin oxide) surfaces. Future research work will involve the incorporation of functionalized iridium oxide nanoparticles in the poly(acrylic acid/acrylamide) films and the characterization of their catalytic activity toward water oxidation. The method will then be extended to tin-oxide and titanium-dioxide semiconductor electrodes for preparing photo-active interfaces.

Soft matter, such as organogels, waxes and polymer films have found numerous applications in various areas of sciences, engineering and medicine. Ability to assess and monitor their structural organization and physical properties is of the outmost importance. However, there are no convenient methods to accomplish this task.
Small molecule environmental probes have been instrumental in providing information about changes of various types of media upon exposure to external stimuli. Our group has demonstrated the validity of using these probes, also known as molecular rotors, for investigating various types of media. This poster will highlight our efforts on the developments and applications of ratiometirc molecular rotors that allow determining structural integrity as well as properties of various industrially important, medically- and energy-relevant soft matter materials.

Liquid-liquid phase separation (LLPS) of protein aqueous mixtures is the reversible condensation of protein-rich micro droplets occurring below a well-defined LLPS temperature. LLPS studies of protein mixtures are fundamental for understanding the membrane-less compartmentalization inside living cells, protein-aggregation diseases, protein-based drug formulations, enzyme-based materials and molecular interactions. It is known that aqueous solutions of the protein lysozyme in the presence of phosphate buffer at neutral pH and physiological salt concentration undergo LLPS upon cooling below ≈ 0 °C. The obtained lysozyme-rich micro droplets rapidly dissolve upon heating above the LLPS temperature. In this work, it will be shown that an apparently undisruptive substitution of phosphate buffer with another well-known buffer, 4-(2-hydroxyethyl)-1-piperazineethanesulfonate (HEPES), to lysozyme aqueous solutions significantly alter the LLPS mechanism. Specifically, contrary to the case of phosphate buffer, the micro droplets produced below ≈ 0 °C remain surprisingly stable upon heating even at ≈ 30-40 °C. Related LLPS studies in both acidic and basic conditions show similar anomalous LLPS behavior. Our results indicate that HEPES triggers a second protein self-assembly process that is catalyzed by LLPS. These findings show that protein aqueous mixtures in the presence of HEPES buffer could be exploited for the preparation of protein-based materials. They also suggest that the combination of a protein self-assembly with LLPS may be a mechanism involved in the formation of membrane-less globular compartments inside the cytoplasm of living cells.