Syntheses and Photoreactivity of Chromene Natural Products

Plants with high phytochemical diversity produce an abundance and varietyof secondary metabolites which increases their chance of producing potent compounds or precursors to combat herbivory. Phototoxins are light activated secondary metabolites that plants can produce for defense against herbivores. Chromene compounds are naturally occurring phototoxins that serve as precursors to toxins that aid in a plant’s defense. Piper kelleyi is a phytochemically diverse species that contains an abundance and assortment of natural products including compounds 1 – 3. Jeffrey Research Group isolated compounds 1 – 3 from Piper kelleyi in 2014 and hypothesized that there is a biosynthetic connection between the three compounds. This hypothesis led to investigations into the biosynthetic relationship between these three compounds as well as an investigation into how the photoactivity of chromene 2 contributes to the phytochemical diversity of Piper kelleyi. The indication of a biosynthetic connection between 1 – 3 gave inspiration for further studies that were conducted with various chromene natural products. 2H-Chromenes are light-activated pharmacophores that form ortho-quinone methide intermediates upon irradiation with UV light. The short-lived, highly reactive ortho-quinone methide intermediate can be utilized in a variety of reactions to produce a library of natural products. The research presented throughout this dissertation demonstrates that the reactivity of the chromene is differentially related to its structure in all the reactions that were explored including nucleophilic trapping, dimerization, and electrophilic aromatic substitution. The nucleophilic trapping and subsequent dimerization reactions presented suggest that the addition of a phenol group on the benzopyran ring changes the reactivity of the chromene. In addition, various 2H-chromene compounds were utilized as electrophiles in light mediated electrophilic aromatic substitution (EAS) reactions. The total syntheses of piperaduncin A and piperaduncin B, isolated from Piper aduncum, were achieved through light mediated EAS. This achievement demonstrates the utility of the OQM intermediate and its ability to serve as an intermediate in natural product synthesis. EAS reactions with various chromenes and electron-rich aryl groups demonstrate that the reactivity of the OQM intermediate as an electrophile is dependent on the structure of the chromene. Herbivory of Piper kelleyi leads to oxidation products and increased compositional diversity. Due to this conclusion, oxidation reactions were performed to determine possible oxidation products present in Piper kelleyi. As series of oxidation reactions utilizing prenylated benzoic acid 1 and chromene 2 produced various oxidation products. These reactions demonstrated the labile nature of compounds 1 and 2 and give insight into potential oxidation pathways occurring in Piper kelleyi. The oxidation reactions presented could be relevant to the phytochemical landscape of Piper kelleyi

Say That The River Turns: Social Justice Intentions in Progressive Public School Classrooms

Fennimore confronts the deficit-based talk prevalent in many schools serving marginalized students in “Say that the River Turns.” She argues that teaching for social justice begins by replacing deficit-based talk with clearly articulated intentions that subsequently transform into actions

A Framework for Integrating Oncology Palliative Care in Doctor of Nursing Practice (DNP) Education

Doctor of Nursing Practice (DNP) faculty play a critical role in preparing students to meet the complex needs of the nation as the number of cancer rates and survivors rise (National Cancer Institute, 2018) and as an unprecedented number of older Americans enter into the healthcare system with complicated comorbidities (Whitehead, 2016). Palliative care has dramatically expanded over the past decade and has been increasingly accepted as a standard of care for people with cancer and other serious, chronic, or life-limiting illnesses. Advanced practice registered nurses (APRNs) are recognized as important providers of palliative care (Walling et al., 2017). A 2-day course was held with support from the National Cancer Institute to enhance integration of palliative oncology care into DNP curriculum. The course participants (N = 183), consisting of DNP faculty or deans, practicing DNP clinicians, and students, received detailed annotated slides, case studies, and suggested activities to increase student engagement with the learning process. Course content was developed and delivered by palliative care experts and DNP faculty skilled in curriculum design. Participants were required to develop goals on how to enhance their school\u27s DNP curriculum with the course content. They provided updates regarding their progress at integrating the content into their school\u27s curriculum at 6, 12, and 18 months post course. Results demonstrated an increase in incorporating oncology palliative care in DNP scholarly projects and clinical opportunities. Challenges to inclusion of this content in DNP curricula included lack of: perceived time in curriculum; faculty educated in palliative care; and available clinical sites

Are They Really Just Cosmetic? the Impact of Cosmetic Items on Fortnite\u27s Gameplay and Game Design

Cosmetic microtransactions, the act of paying for virtual items that customize certain parts of video games and virtual worlds such as skins that change the appearance of the avatar, are looked upon more favorably in the gaming community than performance-enhancing microtransactions, where one pays for virtual items that enhance the abilities of avatars or speed up the progression of the game. Video game industry spokespeople have adapted this rhetoric and emphasized that the microtransactions in their games are for cosmetic items only with no bearing on gameplay. However, the way players use cosmetic items in games and the way cosmetic items inspire certain game mechanics suggest that their function in games isn’t purely ornamental. Using Fortnite as a case study, I argue that cosmetic items can influence gameplay and that the lucrative aspects of cosmetic microtransactions influence game design. Players use cosmetic items not only to be fashionable, but as tools to fashion their own metagames - games within, around, and outside of games. Game companies know that players care about cosmetic items and avatar customization, and they design their games to make cosmetic items as desirable as possible. Cosmetic microtransactions help us understand that visual design is one of the biggest influences on gameplay and the business of games

Evaluation of Broadcast Steam Application with Mustard Seed Meal in Fruiting Strawberry

Soil disinfestation with steam has potential to partially replace fumigants such as methyl bromide, chloropicrin, and 1,3-dichloropropene because it is effective, safer to apply, and has less negative impact on the environment. Here, we compared the efficacy of steam and steam + mustard seed meal (MSM) to chloropicrin on soil disinfection, plant growth, and fruit yield in a strawberry (Fragaria ×ananassa) fruiting field. The MSM was applied at 3368 kg·ha−1 before the steam application. Steam was injected into a 3-m-wide reverse tiller that was set to till 30 to 40 cm deep. Soil temperatures at depths of 10, 20, 25, and 35 cm were monitored. Steam and steam + MSM treatments reduced the viability of purslane seeds and nutsedge tubers, microsclerotia density of Verticillium dahliae, propagule density of Pythium ultimum, cumulative weed densities, and biomass compared with the nontreated control. Moreover, the steam application was as efficacious as chloropicrin on these pests. The growth and fruit yield of strawberries grown on soils previously treated with the steam and steam + MSM treatments were similar to those in the chloropicrin treatment and were higher than those in the nontreated control. Our study indicated that steam, steam + MSM, and chloropicrin are equally effective at suppressing weeds and soilborne pathogens. These results suggest that the steam and steam + MSM treatment can be a practical alternative for soil disinfestation in conventional and organic strawberry fields

Team Teaching, Humor, and Informal Polling Techniques in NECDMC - Based Research Data Management Workshops at Brandeis University

Objective: This poster will detail a few pedagogical techniques incorporated into a series of workshops on research data management. These techniques were chosen to better engage workshop participants by making the material more individually relevant and relatable. Methods: For the second semester in which workshops on research data management (derived from the NECDMC modules) were offered through the Brandeis University Library & Technology Services department, the librarian sought to make the sessions more engaging through several pedagogical techniques. A team teaching approach was employed by inviting senior members of the Technology Help Desk and Hardware Repair Shop to collaborate on and co-teach the workshops. Humor was employed strategically through icons, disaster stories, and select xkcd webcomic strips within the lecture and slides. Informal polling and direct encouragement to share personal anecdotes during the workshop sessions promoted active engagement. Results: Workshop participants were visibly more engaged, asked a greater number of questions, and questions were more directly relevant to the presented material than participants of the first semester\u27s workshops, before these pedagogical techniques were employed. Conclusions: Active and engaged learning techniques are difficult to employ in what are essentially one-shot hour-long instruction sessions, particularly when participants are largely unfamiliar with the material at hand. But by integrating some techniques to capture the interest and encourage participants to make connections to their own experiences we observed a deeper understanding and appreciation of the material

Incorporating Statistical Strategy into Image Analysis to Estimate Effects of Steam and Allyl Isocyanate on Weed Control

Weeds are the major limitation to efficient crop production, and effective weed management is necessary to prevent yield losses due to crop-weed competition. Assessments of the relative efficacy of weed control treatments by traditional counting methods is labor intensive and expensive. More efficient methods are needed for weed control assessments. There is extensive literature on advanced techniques of image analysis for weed recognition, identification, classification, and leaf area, but there is limited information on statistical methods for hypothesis testing when data are obtained by image analysis (RGB decimal code). A traditional multiple comparison test, such as the Dunnett-Tukey-Kramer (DTK) test, is not an optimal statistical strategy for the image analysis because it does not fully utilize information contained in RGB decimal code. In this article, a bootstrap method and a Poisson model are considered to incorporate RGB decimal codes and pixels for comparing multiple treatments on weed control. These statistical methods can also estimate interpretable parameters such as the relative proportion of weed coverage and weed densities. The simulation studies showed that the bootstrap method and the Poisson model are more powerful than the DTK test for a fixed significance level. Using these statistical methods, three soil disinfestation treatments, steam, allyl-isothiocyanate (AITC), and control, were compared. Steam was found to be significantly more effective than AITC, a difference which could not be detected by the DTK test. Our study demonstrates that an appropriate statistical method can leverage statistical power even with a simple RGB index

Mary Pettenger Interview 2020

Dr. Mary Pettenger discusses what her day looks like as a Division Chair and professor at Western Oregon university. She talks about her daily routine, her favorite memories at Western, and her goals for the future