Elkins, WV, United States

Davis and Elkins College

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Elkins, WV, United States
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Wiseman F.L.,Davis and Elkins College | Scott D.W.,East Tennessee State University | Cooper W.C.,Eastern New Mexico University | Tamine J.,Chevron | And 2 more authors.
RSC Advances | Year: 2017

A detailed thermodynamic analysis of the activation parameters for the simple hydrolysis of acetic anhydride in an acetonitrile/water cosolvent system is presented. The activation parameters are obtained using regression analyses of the Eyring rate equation under iso-mole fraction and isodielectric conditions. The iso-mole fraction Eyring plots are linear, indicating the activation enthalpy and entropy are both temperature independent under these conditions. However, the isodielectric Eyring plots are non-linear, and the analysis shows both the activation entropy and activation enthalpy are strongly temperature dependent under isodielectric conditions. The thermodynamic analysis is complemented by linear solvent energy analysis and computational studies of possible transition structures, the latter showing that a concerted six-member ring structure with a single water molecule is the likely transition state. © The Royal Society of Chemistry 2017.


Scott D.W.,East Tennessee State University | Wiseman F.L.,Davis and Elkins College | Cooper W.C.,Eastern New Mexico University | Alseiha Y.S.,East Tennessee State University
Chemical Data Collections | Year: 2017

Values for co-solvents such as acetone and tetrahydrofuran have been measured. Permittivity values of a co-solvent system decrease with increasing temperature and decrease as mole fraction of water decreases. Fit to a cubic polynomial, the coefficients can be used to determine relative permittivity of the co-solvent system knowing temperature and mole fraction. A Brookhaven Instruments BI 870 Dielectric Meter was used. Pure water from 15.0 to 55.0 °C was measured to validate the method. Solutions of acetone and tetrahydrofuran were measured from 15.0 to 55.0 °C. A cubic polynomial fit was used to determine the polynomial coefficients for determining permittivity as a function of temperature and mole fraction. These coefficients may also be used to interpolate the dielectric constant between temperatures. Literature values for acetonitrile, 1,4-dioxane, methanol, ethanol, isopropanol and N,N-dimethylformamide in water were used to determine the polynomial coefficients. © 2017


Cooper W.C.,Eastern New Mexico University | Chilukoorie A.,Eastern New Mexico University | Polam S.,Eastern New Mexico University | Scott D.,East Tennessee State University | Wiseman F.,Davis and Elkins College
Journal of Physical Organic Chemistry | Year: 2017

Recent studies have shown that general-base assisted catalysis is a viable mechanistic pathway for hydrolysis of smaller anhydrides. Therefore, it is the central purpose of the present work to compare and contrast the number of hydrogen atoms in-flight and stationary in the transition state structure of the base-catalyzed mechanisms of 2 hydrolytic reactions as well as determine if any solvent effects occur on the mechanisms. The present research focuses on the hydrolytic mechanisms of N,N-dimethylformamide (DMF) and acetic anhydride in alkali media of varying deuterium oxide mole fractions. Acetic anhydride has been included in this study to enable comparisons with DMF hydrolysis. Comparative studies may give synergistic insight into the detailed structural features of the activated complexes for both systems. Hydrolysis reactions in varying deuterium oxide mole fractions were conducted in concentrations of 2.0M , 2.5M , and 3.0M for DMF and 0.10M for acetic anhydride at 25°C. Studies in varying deuterium mole fractions allow for proton inventory analysis, which sheds light on the number and types of hydrogen atoms involved in the activated complex. For these systems, this type of study can distinguish between direct nucleophilic attack of the hydroxide ion on the carbonyl center and general-base catalysis by the hydroxide ion to facilitate a water molecule attacking the carbonyl center. The numerical data are used to discuss 3 possible mechanisms in the hydrolysis of DMF. © 2017 John Wiley & Sons, Ltd.


Stove S.K.,Davis and Elkins College | Mabry M.L.,Lenoir-Rhyne University
Bioscene | Year: 2010

A program-level assessment of the biology curriculum at a small liberal arts college validates a previous study demonstrating success in achieving learning outcomes related to content knowledge and communication skills. Furthermore, research opportunities have been provided to complement pedagogical strategies and give students a more complete science education.


Bolyard C.,Davis Health System | Dunn C.,Davis and Elkins College | Adams J.,Davis and Elkins College | Stover S.,Davis and Elkins College
Journal of Exercise Physiology Online | Year: 2013

It has been demonstrated that regular aerobic exercise can have positive effects on body mass index (BMI) and cardiovascular (CV) function. However, increasing exercise duration and frequency can also result in excessive production of reactive oxygen species and subsequent oxidation of reduced glutathione (GSH). It was hypothesized that GSH is upregulated in response to increasing exercise rigor to neutralize the effects of reactive oxygen. Based on their reported aerobic exercise routines, 24 subjects (10 males, 14 females) were placed into 1 of 3 experimental groups: (a) minimum rigor (MIN); (b) moderate rigor (MOD); and (c) maximum rigor (MAX). Over the course of a 3-month study, the subjects maintained their normal training routines, and BMI, heart rate (HR), blood pressure, and salivary GSH concentration were assessed regularly. The average BMI decreased as training rigor increased. The average HR of the MAX group was significantly lower than that of the other two groups. The average blood pressure values of the MOD and MAX groups were significantly lower than those of the MIN group. Finally, there was no significant difference between the average salivary GSH concentrations in the 3 groups. In summary, while increasing duration and frequency of aerobic exercise training improved BMI, HR, and blood pressure, the increased efficiency of the CV system was accompanied by an upregulation of GSH that protects the tissues from exercise-induced oxidative stress.


Calhoun W.R.,Virginia Commonwealth University | Maeta H.,Miami University Ohio | Roy S.,Davis and Elkins College | Bali L.M.,Miami University Ohio | Bali S.,Miami University Ohio
Journal of Dairy Science | Year: 2010

We demonstrate a first simultaneous measurement of both the refractive index and the attenuation coefficient (defined as the sum of the scattering and absorption coefficients) of highly turbid milk and milk-cream mixtures. We achieve this by observing the real-time reflectance profile of a divergent laser beam made incident on the surface of the milk sample. The experiments were carried out on commercial milk samples with fat volume concentrations of 0.5 or less, 1.6, and 3.3%, and on milk-cream mixtures with fat volume concentrations of 10 and 33.3%, without any dilutions of these samples. We find that the reflectance data are well described, for the first time without any empirical fit-parameters, by Fresnel theory that correctly includes the effect of angle-dependent penetration into the turbid medium on the total internally reflected signal. Therefore, our method provides the most accurate determination to date of the refractive index and attenuation coefficient of milk and milk-cream mixtures. Our sensor is compact, portable, and inexpensive. © 2010 American Dairy Science Association.


Gaylor M.O.,Davis and Elkins College | Harvey E.,Virginia Institute of Marine Science | Hale R.C.,Virginia Institute of Marine Science
Chemosphere | Year: 2012

Polybrominated diphenyl ether (PBDE) flame retardants are added at percent levels to many polymers and textiles abundant in human spaces and vehicles, wherein they have been long assumed to be tightly sequestered. However, the mgkg -1 burdens recently detected in indoor dust testify to substantial releases. The bulk of released PBDEs remain in the terrestrial environment, yet comparatively little research focuses on this compartment. There, insects/arthropods, such as crickets, are the most abundant invertebrate organisms and facilitate the trophic transfer of contaminants by breaking down complex organic matter (including discarded polymers) and serving as food for other organisms. Our experiments revealed that house crickets (Acheta domesticus) provided uncontaminated food and free access to PUF containing Penta-BDE (8.7%drywt) for 28d accumulated substantial PBDE body burdens. Crickets allowed to depurate gut contents exhibited whole body burdens of up to 13.4mgkg -1 lipid ΣPenta-BDE, 1000-fold higher than typically reported in humans. Non-depurated crickets and molted exoskeletons incurred even higher ΣPenta-BDE, up to 80.6 and 63.3mgkg -1 lipid, respectively. Congener patterns of whole crickets and molts resembled those of PUF and the commercial Penta-BDE formulation, DE-71, indicative of minimal discrimination or biotransformation. Accumulation factor (AF) calculations were hampered by uncertainties in determining actual PUF ingestion. However, estimated AFs were low, in the range of 10 -4-10 -3, suggesting that polymer-PBDE interactions limited uptake. Nonetheless, results indicate that substantial PBDE burdens may be incurred by insects in contact with current-use and derelict treated polymers within human spaces and solid waste disposal sites (e.g. landfills, automotive dumps, etc.). Once ingested, even burdens not absorbed across the gut wall may be dispersed within proximate terrestrial food webs via the insect's movements and/or predation. © 2011 Elsevier Ltd.


Stover S.K.,Davis and Elkins College | McArthur L.B.,Davis and Elkins College | Mabry M.L.,Lenoir-Rhyne University
Bioscene | Year: 2013

Although evidence supporting anthropogenic global warming and evolution by natural selection is considerable, the public does not embrace these concepts. The current study explores the hypothesis that individuals will become more receptive to scientific viewpoints if evidence for evolution and implications of global warming are presented as issues of public health. Non-science majors, nursing students, and freshman biology majors from two similar institutions answered pre- and post-test survey questions addressing the autism-vaccine connection, public health issues related to global warming, and public health issues associated with evolution by natural selection. Pretest questions elicited simple yes/no responses, whereas post-test questions were presented with relevant public health-related information and required students to articulate specific rationales. Student responses were categorized as either "evidence-based" or "non-evidence-based." Only the natural selection question produced post-test responses that were significantly different from pretest responses. There were significantly more post-test "evidence-based" responses to the natural selection question in all three student groups. Results indicate that the presentation of controversial topics, particularly evolution, in the context of public health could be used to encourage public acceptance of scientific viewpoints.


PubMed | Davis and Elkins College
Type: Journal Article | Journal: Journal of religion and health | Year: 2013

The menstrual taboo continues to be a primary reason why women in Judaism and Christianity are excluded from positions of authority. This is demonstrated by examining positions taken toward menstruation by religious leaders in past history and in the present day. Jesus and Gregory the Great are notable exceptions to the disdain expressed by male religionists toward menstruants. Only after the removal of this persistent taboo will religious bodies come to treat women as full participants.


PubMed | Davis and Elkins College
Type: Journal Article | Journal: Chemosphere | Year: 2012

Polybrominated diphenyl ether (PBDE) flame retardants are added at percent levels to many polymers and textiles abundant in human spaces and vehicles, wherein they have been long assumed to be tightly sequestered. However, the mgkg(-1) burdens recently detected in indoor dust testify to substantial releases. The bulk of released PBDEs remain in the terrestrial environment, yet comparatively little research focuses on this compartment. There, insects/arthropods, such as crickets, are the most abundant invertebrate organisms and facilitate the trophic transfer of contaminants by breaking down complex organic matter (including discarded polymers) and serving as food for other organisms. Our experiments revealed that house crickets (Acheta domesticus) provided uncontaminated food and free access to PUF containing Penta-BDE (8.7%drywt) for 28 d accumulated substantial PBDE body burdens. Crickets allowed to depurate gut contents exhibited whole body burdens of up to 13.4 mg kg(-1) lipid Penta-BDE, 1000-fold higher than typically reported in humans. Non-depurated crickets and molted exoskeletons incurred even higher Penta-BDE, up to 80.6 and 63.3 mg kg(-1) lipid, respectively. Congener patterns of whole crickets and molts resembled those of PUF and the commercial Penta-BDE formulation, DE-71, indicative of minimal discrimination or biotransformation. Accumulation factor (AF) calculations were hampered by uncertainties in determining actual PUF ingestion. However, estimated AFs were low, in the range of 10(-4)-10(-3), suggesting that polymer-PBDE interactions limited uptake. Nonetheless, results indicate that substantial PBDE burdens may be incurred by insects in contact with current-use and derelict treated polymers within human spaces and solid waste disposal sites (e.g. landfills, automotive dumps, etc.). Once ingested, even burdens not absorbed across the gut wall may be dispersed within proximate terrestrial food webs via the insects movements and/or predation.

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