1025 research outputs found
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Freedom of Speech on College Campuses
No full textThis study is an attempt to understand why people, specifically college students, do or do not tolerate different forms of speech and expression. Political tolerance is the classic dependent variable used to measure opinion on civil liberties. Existing literature on political tolerance suggests that it is affected by political leanings, education, perception of opposing ideologies, and gender, among other things. Prior research is lacking that targets college students and that differentiates opinions of free speech relating to public life from opinions relating to life on a private campus. The results of a survey of 522 Susquehanna University students indicate that a student’s political affiliation, interest in politics, political sophistication, perception of racism, status as a victim of derogatory speech, year in school, and gender all have a significant effect on opinions relating to the regulation of speech both in public life and on a private campus
Are You Gonna Eat That?: The Ethical and Environmental Implications of Our Food Culture
No full textThe way we eat is uniquely American, and it has many implications for not only our health, but also the health of the planet. Beef is among the most popular meats consumed in the United States, and it also happens to be one of the worst for our health and for the environment. Lab-grown meat is a viable up-and-coming alternative, but it too faces its own challenges that it must overcome before it has the chance to surpass traditional beef in popularity. Switching to a more plant-based diet is generally healthier, but there are some surprising and unexpected environmental consequences to some of the most popular alternatives. Navigating our nation’s food culture is complicated and difficult, and it forces consumers to make tough choices. This study considers how we might best inform our choices through ethical and environmental considerations
Variation in total mercury content of spiders from coal-impacted areas in Central Pennsylvania
No full textMercury is an important and persistent pollutant in the state of Pennsylvania but its transport between terrestrial and aquatic food chains is poorly understood. We measured mercury levels among spider taxa near various coal-impacted areas adjacent to or away from aquatic systems. These areas were compared to agricultural and headwater stream reference sites. Mine fire sites had the highest mercury levels in spiders. Riparian zones just upstream of a powerplant had significantly lower mercury levels than downstream and headwater streams had levels as high as powerplant-adjacent sites. We also found significantly higher mercury among riparian spiders near the powerplant compared to agricultural sites. Spider size was unrelated to mercury level. Ground spiders are particularly good bioindicators of mercury mobilization across aquatic and terrestrial interfaces within coal-impacted areas. Aquatic sources are important, but not necessary for significant trophic transfer among terrestrial arthropod predators
Synthesis of oxobutanoate-substituted carvacrol and thymol derivatives as potential antibacterial agents
No full textThe major components of oregano oil are the isomeric phenols, carvacrol and thymol. These phenols have a wide range of biological activities including anticancer, antibacterial, and insecticidal properties. Previous studies have shown that conversion of carvacrol and thymol to their corresponding ester and carbamate derivatives led to retention or enhancement of antibacterial activity. In the current study, fourteen oxobutanoate derivatives of ethyl carvacrol and ethyl thymol have been prepared for evaluation of their antibacterial effects against clinically isolated Staphylococcus aureus strains. Ethyl carvacrol and ethyl thymol were prepared by the Williamson ether synthesis. The oxobutanoic acid moiety was introduced to the carvacrol/thymol core via Friedel-Crafts acylation, followed by alkylation to afford the carvacrol/thymol-oxobutanoates. The synthesized compounds were obtained in good yield and characterized by NMR spectroscopy
Studies towards the total synthesis of Lobophorol A
No full textLobophorol A is metabolite recently isolated from the marine algae of Lobophora variegata that demonstrated potential antibacterial activity. Like many natural products, total synthesis remains the best means to obtain enough amounts of these compounds for further biological testing. In order to develop a general synthetic route to lobophorol A, several derivatives were synthesized lacking the external acetyl group to determine if this acetyl group was imperative for activity of lobophorol A derivatives. A modified synthetic approach was used with a 1,4 Michael addition of diethyl malonate to a,b-unsaturated ketones. These reactions induced a ring closing and, after hydrolysis and decarboxylation, lead to the desired derivatives. Further studies will be conducted with other derivatives with different substituents as the aliphatic side chain to test how they affect the activity against S. aureus. The derivatives that were successfully synthesized will be tested in the near future for their biological activity against S. aureus and these activities will be reported at a future date
Lethal and Sublethal Effects of Cedar Oil Derivatives on Wolf Spiders
No full textCommercial cedar oil has been used as an insecticide and insect repellent. It contains several nicotine-like compounds that have been poorly tested for their effects on beneficial non-target species like spiders. We derived 16 compounds from cedar oil. The wolf spider Tigrosa helluo were behaviorally assayed before and after exposure to volatiles of these compounds. Spider activity and courtship latency increased among test compounds during post-trials, but we found no evidence of avoidance in choice tests. Pardosa milvina wolf spiders exposed to wet contact showed neurological responses to most compounds. Only three compounds resulted in premature mortality relative to the control over a month. We found significant sublethal and delayed lethal effects of some of these compounds on both wolf spider species. These species are abundant in crop systems. Results suggest that cedar oil derivatives used on agricultural crops could reduce the beneficial effects of biological controls in these systems
Retrograde Amnesia for a UCS Preexposure Memory
No full textThe UCS preexposure effect is a phenomenon in which exposure to an unconditioned stimulus (UCS) prior to its pairing with a conditioned stimulus (CS) retards later learning, while also producing a competing memory. The current studies aim to investigate whether preexposure to a UCS is susceptible to amnesia. The first experiment demonstrated the UCS preexposure effect using a tone-shock fear conditioning paradigm. After validating the UCS preexposure effect in Experiment 1, the second experiment investigated whether administration of an amnestic agent, cycloheximide, would prevent the inhibitory effect of UCS preexposure. Results showed animals in the saline control group demonstrated less freezing behaviors than the experimental animals when tested. These findings provide evidence that cycloheximide (a protein synthesis inhibitor) caused amnesia for preexposure, and alleviating the competing memory formed by UCS preexposure
Microwave-Assisted Hydrogenations Using Frustrated Lewis Pairs
No full textFrustrated Lewis pairs (FLP) consist of sterically hindered Lewis acid and base, for which the formation of classical Lewis acid-base adducts do not form. Within one decade, the metal-free catalytic hydrogenation has rapidly managed to progress, and the substrate scope has been broadened to a wide variety of functional groups, such as heterocycles, aldehydes, and ketones. However, the strict anhydrous reaction conditions and sensitivity for other functional groups for FLP-catalyzed hydrogenation has seriously limited the applications of this methodology, which prevented FLPs from being truly viable alternatives for transition metal hydrogenation catalysts. In this study, a more applicable and efficient Green Chemistry technique, microwave irradiation, was used as the source of heat. By transferring heat directly to a closed system, the reaction time was significantly reduced. Cyclopentyl methyl ether (CPME) was identified as the most efficient solvent among those tested. Other optimal reaction parameters, such as temperature, and pressure were also studied. High yields were achieved under the experimental conditions. The scope and limitations of this methodology will be presented
Female Representation in Legislatures and Their Effect on Social Welfare Policy
No full textIn my research we will be looking at the increasing percentage of females in legislatures in the 35 OECD countries (independent variable) and their effect on the percentage of government expenditure on social welfare policies (dependent variable). In this study, social welfare expenditure will be comprised of family, education, and health policies. Aside from my independent and dependent variables, I have included controls such as GDP, Gini coefficient, % of government expenditure on military, and the three welfare regimes as characterized by Esping- Anderson. I will use Stata to run multiple regression tests with the goal of proving my hypothesis that an increase percentage of women in legislature will have a positive correlation with an increased percentage of government expenditure on social welfare policy
Children’s Understanding of the Natural Numbers’ Structure
No full textWhen young children attempt to locate numbers along a number line, they show logarithmic (or other compressive) placement. For example, the distance between “5” and “10” is larger than the distance between “75” and “80.” This has often been explained by assuming that children have a logarithmically scaled mental representation of number (e.g., Berteletti, Lucangeli, Piazza, Dehaene, & Zorzi, 2010; Siegler & Opfer, 2003). However, several investigators have questioned this argument (e.g., Barth & Paladino, 2011; Cantlon, Cordes, Libertus, & Brannon, 2009; Cohen & Blanc-Goldhammer, 2011). We show here that children prefer linear number lines over logarithmic lines when they do not have to deal with the meanings of individual numerals (i.e., number symbols, such as “5” or “80”). In Experiments 1 and 2, when 5-and 6-year-olds choose between number lines in a forced-choice task, they prefer linear to logarithmic and exponential displays. However, this preference does not persist when Experiment 3 presents the same lines without reference to numbers, and children simply choose which line they like best. In Experiments 4 and 5, children position beads on a number line to indicate how the integers 1–100 are arranged. The bead placement of 4-and 5-year-olds is better fit by a linear than by a logarithmic model. We argue that previous results from the number-line task may depend on strategies specific to the task