17 research outputs found
O True Apothecary: How Forensic Science Helps Solve a Classic Crime
As part of a university-wide project to explore Shakespeare’s classic play, Romeo and Juliet, from a variety of perspectives, an interdisciplinary talk was presented to the university community on the chemistry of the potions and poisons referenced in Romeo and Juliet. To draw the multidisciplinary audience in and to teach about forensics as well as pharmaceutical herbs and chemicals, the presentation was given from the perspective of how a modern crime scene investigator would approach the famous play’s final death scene without any prior knowledge of the situation. An autopsy of Juliet’s body might have revealed the presence of the chemicals, hyoscine and atropine, that come from the plant Atropa belladonna. The autopsy could reveal whether the Friar had set out to sedate Juliet or if he had attempted to kill her. An autopsy of Romeo’s body might have revealed the presence of aconitine from the plant Aconitum napellus. Using a classic story to teach about chemistry, basic ideas were introduced about forensics and pharmacology, emphasizing the importance of dose when determining the effect of a drug on the human body
BASE (Broadening Access to Science Education) Camp for Young Women
This poster will describe the development and implementation of an annual two-week residential summer science enrichment program for 24 rising female juniors and seniors from Bridgeport, CT, a community comprised of many health disparity populations traditionally underrepresented in science. The program, entitled BASE (Broadening Access to Science Education), has an overall goal to excite and inform students from local health disparity populations about the process and promise of science in an effort to increase interest in the pursuit of STEM and health careers after college. The program includes three key components. The first component is the Research Immersion Experience, a weeklong scientific research experience that engages students in faculty-led research projects. The second component of the camp is the Science and Health Careers Exploration that exposes students to various careers in science, technology, and health sciences and the academic paths required to get there. The final component of the program is the College Admissions Counseling in which the Fairfield University Office of Undergraduate Admissions educates the students about the process and requirements for admission to college, informs students about financial aid opportunities, and engages students in mock interviews and essay writing. We will present pre- and post-camp participant, and post-camp counselor, and faculty survey results from 2012. Camper feedback is overwhelmingly positive, and the program appears to be meeting its goals to excite and inform students from health disparity populations about science and to inspire them to pursue scientific careers
BASE (Broadening Access to Science Education): A Research and Mentoring Focused Summer STEM Camp Serving Underrepresented High School Girls
BASE (Broadening Access to Science Education) Camp is a hands-on two-week residential summer science experience on the Fairfield University campus, in Fairfield CT, USA. The annual program targets 24 young women who attend high school in our neighboring city of Bridgeport, CT, the most economically depressed city in CT. The camp, which is free to students, includes three components. The first is the week-long Research Immersion Experience, which engages students in faculty-mentored science research projects assisted by current undergraduate STEM majors. The second component is Career Exploration, which allows students to explore a variety of careers in science, technology, and healthcare, as well as the academic paths required to get there. The third component is College Admissions Counseling, which links campers with Fairfield University’s undergraduate admissions staff for mentoring on the college application process. This program is particularly unique in that it rests entirely on a female staff, engaging Fairfield University’s women STEM faculty and undergraduate STEM majors. BASE Camp was founded and developed through funding from several organizations, and is currently supported by a five-year R25 grant from the NIMHD (National Institute on Minority Health and Health Disparities), National Institutes of Health. After four years in this format, the program has engaged close to 100 young women. Data collected show nearly 100% camper satisfaction with the program. In addition, we found the camp increased camper perception of their science knowledge and confidence, as well as understanding of skills required to succeed in careers in science and health. Finally, in a follow-up survey we found that 95% have applied to, or plan to apply to, college, and 87% are interested in pursuing a STEM or health-related career. The close mentorship of these young women by female role models at the faculty and undergraduate levels has greatly contributed to the success and efficacy of this experience. We hope our program can be used as a model for others to create programming in an effort to promote and support underrepresented women in the pursuit of STEM careers
Antimicrobial Activity in the Pallial Cavity Fluids of the Oyster Crassostrea virginica (Gmelin) from a Highly Impacted Harbor in Western Long Island Sound
Fluid and its associatedmucus from the pallial (mantle) cavity of eastern oysters Crassostrea virginica (Gmelin) from Black RockHarbor, Bridgeport, Connecticut, inhibited growth of both Gram-positive (Bacillus subtilis, Staphylococcus aureus) and Gram-negative (Escherichia coli, Serratia marcescens, and Vibrio parahaemolyticus) bacteria in antimicrobial assays. In the presence of oyster fluid, E. coli resulted in significant reduction in growth after 26 h. Soluble lysozyme activity in pallial cavity fluid of oysters collected in the fall was 3 times greater than that measured in combined winter—spring—summer samples (P = 0.0008). During the course of the study, copper concentrations in pallial cavity fluid ranged from 0.60–2.49 ppm and zinc concentrations ranged from 9.7–61.0 ppm. Copper concentrations remained relatively constant throughout the study; the highest zinc concentrations were recorded in the fall. Fall antimicrobial assays showed heightened antimicrobial activity compared with the spring, which may be the result of increased lysozyme activity and higher zinc concentrations present in the pallial cavity fluid at that time of year. Results of this study suggest that pallial cavity fluid and its associated mucus likely serve an important role in defense-related functions as the first line of defense against infections from environmental pathogens in Crassostrea virginica
Parallel variation of mass transport and heterogeneous and homogeneous electron transfer rates in hybrid redox polyether molten salts
Metal complexes can be prepared as highly viscous (semisolid), room temperature molten salts by combining them with oligomeric polyether substituents. The fluidity and transport properties of these hybrid redox polyether melts can be systematically manipulated by changing the oligomeric chain lengths and by adding unattached oligomers as plasticizers. This paper describes the voltammetrically measured transport properties of several Co(II) polypyridine (2,2‘-bipyridine, phenanthroline) melts. The properties evaluated are the physical self-diffusion coefficient (DPHYS) of the cationic complex in its melt, the diffusivity of its counterion (DCION), the heterogeneous electron-transfer rate constant (kHET) of the Co(III/II) oxidation at the electrode surface, and the rate constant (kEX) for homogeneous electron self-exchange between Co(II) and Co(I) in the mixed valent layer next to the electrode. These dynamics parameters change in parallel manners, over a large (\u3e103) range of values, when the melt fluidity is changed by plasticizers or temperature. While kHET and kEX both change systematically with DPHYS, they change on a more nearly proportional basis with DCION. The latter relationship is interpreted as a kind of solvent dynamics control in which both the homogeneous Co(II/I) and heterogeneous Co(III/II) reaction rates are controlled by the ionic atmosphere relaxation time constant, namely, the time constant of redistribution of counterions following an electron-transfer step that has produced a nonequilibrium charge distribution. DCION provides a measure of the ion atmosphere relaxation rate
Ion atmosphere relaxation controlled electron transfers in cobaltocenium polyether molten salts
A room-temperature redox molten salt for the study of electron transfers in semisolid media, based on combining bis(cyclopentadienyl)cobalt with oligomeric polyether counterions, [Cp2Co](MePEG350SO3), is reported. The transport properties of the new molten salt can be varied (plasticized) by varying the polyether content. The charge transport rate during voltammetric reduction of the ionically conductive [Cp2Co](MePEG350SO3) molten salt exceeds the actual physical diffusivity of [Cp2Co]+ because of rapid [Cp2Co]+/0 electron self-exchanges. The measured [Cp2Co]+/0 electron self-exchange rate constants (kEX) are proportional to the diffusion coefficients (DCION) of the counterions in the melt. The electron-transfer activation barrier energies are also close to those of ionic diffusion but are larger than those derived from optical intervalent charge-transfer results. Additionally, the [Cp2Co]+/0 rate constant results are close to those of dissimilar redox moieties in molten salts where DCION values are similar. All of these characteristics are consistent with the rates of electron transfers of [Cp2Co]+/0 (and the other donor−acceptor pairs) being controlled not by the intrinsic electron-transfer rates but by the rate of relaxation of the ion atmosphere around the reacting pair. In the low driving force regime of mixed-valent concentration gradients, the ion atmosphere relaxation is competitive with electron transfer. The results support the generality of the recently proposed model of ionic atmosphere relaxation control of electron transfers in ionically conductive, semisolid materials
Metal Core Bonding Motifs of Monodisperse Icosahedral Au13 and Larger Au Monolayer-Protected Clusters As Revealed by X-ray Absorption Spectroscopy and Transmission Electron Microscopy
The atomic metal core structures of the subnanometer clusters Au13[PPh3]4[S(CH2)11CH3]2Cl2 (1) and Au13[PPh3]4[S(CH2)11CH3]4 (2) were characterized using advanced methods of electron microscopy and X-ray absorption spectroscopy. The number of gold atoms in the cores of these two clusters was determined quantitatively using high-angle annular dark field scanning transmission electron microscopy. Multiple-scattering-path analyses of extended X-ray absorption fine structure (EXAFS) spectra suggest that the Au metal cores of each of these complexes adopt an icosahedral structure with a relaxation of the icosahedral strain. Data from microscopy and spectroscopy studies extended to larger thiolate-protected gold clusters showing a broader distribution in nanoparticle core sizes (183 ± 116 Au atoms) reveal a bulklike fcc structure. These results further support a model for the monolayer-protected clusters (MPCs) in which the thiolate ligands bond preferentially at 3-fold atomic sites on the nanoparticle surface, establishing an average composition for the MPC of Au180[S(CH2)11CH3]40. Results from EXAFS measurements of a gold(I) dodecanethiolate polymer are presented that offer an alternative explanation for observations in previous reports that were interpreted as indicating Au MPC structures consisting of a Au core, Au2S shell, and thiolate monolayer
Teaching Chemistry with Forensic Science
In addition to being an editor, Amanda S. Harper-Leatherman is a contributing author with Linda N. Roney, Interdisciplinary Learning Activity Incorporating Forensic Science and Forensic Nursing, Chapter 8, pp. 137-153.https://digitalcommons.fairfield.edu/chemistry-books/1005/thumbnail.jp
Encapsulating cytochrome c in silica aerogel nanoarchitectures without metal nanoparticles while retaining gas-phase bioactivity
Applications such as sensors, batteries, and fuel cells have been improved through the use of highly porous aerogels when functional compounds are encapsulated within the aerogels. However, few reports on encapsulating proteins within sol–gels that are processed to form aerogels exist. A procedure for encapsulating cytochrome c (cyt. c) in silica (SiO2) sol-gels that are supercritically processed to form bioaerogels with gas-phase activity for nitric oxide (NO) is presented. Cyt. c is added to a mixed silica sol under controlled protein concentration and buffer strength conditions. The sol mixture is then gelled and the liquid filling the gel pores is replaced through a series of solvent exchanges with liquid carbon dioxide. The carbon dioxide is brought to its critical point and vented off to form dry aerogels with cyt. c encapsulated inside. These bioaerogels are characterized with UV-visible spectroscopy and circular dichroism spectroscopy and can be used to detect the presence of gas-phase nitric oxide. The success of this procedure depends on regulating the cyt. c concentration and the buffer concentration and does not require other components such as metal nanoparticles. It may be possible to encapsulate other proteins using a similar approach making this procedure important for potential future bioanalytical device development