Greenhouse Sanitation: Efficacy of Disinfectants on Cutting Blades Using Tobacco mosaic virus on Petunia as a Model

Winner, 2008 CFAES Undergraduate Research Competition, Plant Sciences DivisionPresented at International (Brazil) University Undergraduate Research ExchangePetunias (Petunia x hybrida) are one of the most popular ornamental crops in the United States. In the early 1990’s, the introduction of asexually propagated petunias into the landscape market was associated with increased reports of virus infections, including Tobacco mosaic virus (TMV), which is transmitted mechanically. In greenhouses, TMV can be transferred to cutting tools, subsequently infecting healthy stock plants and cuttings. An outbreak of TMV in a greenhouse can quickly spread and devastate entire crops, rendering them unsalable. During vegetative propagation, multiple cuttings are taken from one mother stock plant and multiple stock plants are commonly used. Tool disinfection is critical in preventing the spread of pathogens during this process. At this time, there is no disinfectant that is labeled for greenhouse use against plant viruses with a reasonable contact time. Commercially available disinfectants and other materials were tested at varying concentrations and contact times to determine the most effective treatments to reproducibly prevent transmission of TMV to healthy plants. Two cultivars of petunia plantlets were tested with eight treatments by dipping razor blades in TMV-contaminated plant sap, then the disinfectant, then making a cut on a healthy plant. Post-inoculation, the petunias were sampled and tested for TMV by double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA). Based on these results, the four most effective treatments were used in a trial to more closely simulate vegetative propagation. All treatments tested reduced incidence of TMV infection from contaminated razor blades. The most effective one-minute disinfectant treatments in these studies were: 20% non-fat dry milk, 20% non-fat dry milk plus surfactant, 1:10 household bleach, and 1% Virkon®S.Ohio Agricultural Research and Development Center (OARDC) SEEDS grantOSU Honors and Scholars Research GrantUSDA Floriculture and Nursery Research InitiativeEuroAmerican PropagatorsDümmen USA/Red FoxTimbuk II FarmsNo embarg

The Story within Lessons: Highlighting Moments of Student Inquiry

The curricular decisions of K-12 mathematics teachers affect student learning. One way to make sense of this is to find the story within the lesson. Writing the story of a lesson by identifying the plot, characters, settings, and actions reveals the questions that drive student mathematical curiosity and inquiry (Dietiker, 2015). Drawing attention to these moments provides a new perspective for teachers as they plan, teach, and reflect on their lessons and work to improve their instruction for their students as they see the possible advantages and disadvantages of the ordering of mathematical tasks. This work extends Dietiker’s thinking through writing the story of calculus lessons introducing the definite integral

Blogs and Feature Articles: Foster Youth in Higher Education, Superheroine Figures in Film, and More

Herein is my portfolio which exhibits my collective work in a journalism workshop class. This includes several blogs and feature articles that were completed within a semester. The blogs and articles mainly cover the topics of foster youth in higher education and a current issue/trend within film and television culture. As a current LMU Guardian Scholar, my interest lies in covering news and feature stories that highlight these Guardian Scholars Programs on other college campuses in the greater Los Angeles area and what various social support services they are providing to their students to help them combat the hurdles of economic hardship and the lack of family support. I intend to create a final portfolio of related news stories including a reaction story and in-depth profile that showcases a comprehensive exploration of Guardian Scholars Programs, its staff, and people who work in the field of improving the lives of at-risk youth. While these articles offer a glimpse at diversity on college campuses, ultimately they will illustrate a universal human experience of perseverance and determination. I also explore a creative topic within the film industry which is showcased in an issue/trend story. This required extensive reporting, research, and group work. I hope to bring light to a current film/television issue and how it is impacting film professors and students at Loyola Marymount University

Paying for College Success: An Introduction to the Performance-Based Scholarship Demonstration

This policy brief describes a demonstration launched by MDRC in four states in 2008 to evaluate whether performance-based scholarships -- paid contingent on attaining academic benchmarks -- are an effective way to improve persistence and academic success among low-income college students. The demonstration builds on positive results from an earlier MDRC study in Louisiana

Cell viability and cytokine production of human alveolar epithelial cells following exposure to sulphur dioxide

Exposure to air pollutants is significantly associated with health risks ranging from bronchial reactivity to morbidity and mortality. However, the precise mechanisms are not always fully understood. The aim of this study was to investigate the effects of sulphur dioxide (SO2) on cell viability and cytokine production of A549-human pulmonary epithelial cells. Test atmospheres of SO2 were generated using a direct dilution method and calibrated by ion-chromatography. Test atmospheres were delivered to lung cells cultured on porous membranes (0.4 μm) using Harvard Navicyte horizontal diffusion chamber systems. The cytotoxic endpoints were investigated using the MTS (tetrazolium salt; Promega), NRU (neutral red uptake; Sigma) and ATP (adenosine triphosphate; Promega) assays. Expression of inflammatory markers including tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were evaluated using double-antibody immunometric assays. Dose-dependent effects of SO2 were observed in A549 cells using all in vitro assays at test concentrations (10-200 ppm). The ATP assay appeared to be the most sensitive test (IC50 = 48 ± 2.83 ppm) that may related to the impaired metabolic activity of the cells following SO2 exposure. After analysis of TNF-α, no statistically significant differences were observed between control and exposed cells. However, the IL-6 production in A549 cells was significantly reduced in a dose-dependent manner (P\u3c0.05). These results suggest that SO2 may induce a functional alteration of cells of the pulmonary epithelial preventing cells to produce adequate amounts of IL-6. IL-6 as a multifunctional proinflammatory cytokine may regulate cellular responses and plays a significant role in inflammation and tissue injury

Knowledge and Perceptions of SLP Graduate Students Regarding Multiculturalism

Populations in the United States rise daily, as do the number of people who are considered multicultural. With this comes a greater need for speech-language pathologists (SLPs) who are able to assess and treat such individuals – a training process that begins in graduate programs. The primary objective of this study was to determine the knowledge and perceptions of graduate students in speech-language pathology as it pertains to multiculturalism. A survey was conducted to explore graduate students’ knowledge and perceptions of multicultural topics. Participants were recruited from programs in the southeastern United States via email. Just under 400 surveys were returned with 322 complete responses received. Most graduate programs are covering multicultural and multilingual topics across courses to prepare students to work with such populations in future careers. Students recognize the importance of these topics because the opportunities to work with multicultural and multilingual clients are becoming more frequent. A firm foundation can set the tone for an SLP’s career; without adequate training in the area of multiculturalism, many individuals may receive inadequate services whether the speech-language pathologist recognizes the gaps in care or not

Substantial yield reduction in sweet potato due to tropospheric ozone, the dose-response function

Impacts of tropospheric ozone on sweet potato (Ipomoea batatas) are poorly understood despite being a staple food grown in locations deemed at risk from ozone pollution. Three varieties of sweet potato were exposed to ozone treatments (peaks of: 30 (Low), 80 (Medium), and 110 (High) ppb) using heated solardomes. Weekly measurements of stomatal conductance (gs) and chlorophyll content (CI) were used to determine physiological responses, along with final yield. gs and CI were reduced with increasing ozone exposure, but effects were partially masked due to elevated leaf senescence and turnover. Yield for the Erato orange and Murasaki varieties was reduced by ∼40% and ∼50% (Medium and High ozone treatments, respectively, vs Low) whereas Beauregard yield was reduced by 58% in both. The DO3SE (Deposition of Ozone for Stomatal Exchange) model was parameterized for gs in response to light, temperature, vapour pressure deficit and soil water potential. Clear responses of gs to the environmental parameters were found. Yield reductions were correlated with both concentration based AOT40 (accumulated ozone above a threshold of 40 ppb) and flux based POD6 (accumulated stomatal flux of ozone above a threshold of 6 nmol m− 2 s− 1) metrics (R2 0.66 p = 0.01; and R2 0.44 p = 0.05, respectively). A critical level estimate of a POD6 of 3 (mmol m−2 Projected Leaf Area−1) was obtained using the relationship. This study showed that sweet potato yield was reduced by ozone pollution, and that stomatal conductance and chlorophyll content were also affected. Results from this study can improve model predictions of ozone impacts on sweet potato together with associated ozone risk assessments for tropical countries

La ionosfera: comunicare... naturalmente!

La ionosfera è la parte della media-alta atmosfera compresa tra i 60 e i 1000 km di quota. Essa è caratterizzata da una concentrazione di elettroni tale da modificare la propagazione delle onde radio che la attraversano