ScholarWorks@UMassAmherst

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Featured Items

UMOP 42: Historical reflections in celebration of the 50th Anniversary of UMass Linguistics

UMOP 42: Papers in celebration of the 50th Anniversary of UMass Linguistics

SNAP Workers: Working People & SNAP Benefits in Massachusetts

Kerrissey, Jasmine; Meyers, Nathan

Established by the Food Stamp Act in 1964, SNAP is the country’s largest anti-hunger program. SNAP, the Supplemental Nutrition Assistance Program, also known as food stamps, provides food assistance to low-income families. The program serves over 41 million people, or 12.3% of U.S. residents. Massachusetts has a higher SNAP rate than the U.S, with 16% of the Massachusetts population receiving SNAP. This report examines workers in Massachusetts who live in households that receive SNAP benefits. The analyses use data from the American Community Survey (ACS), a representative survey administered by the Census Bureau. The report examines the most recent and comprehensive available ACS data, 2019-2023. See the methodological appendix for details.

2025-11-24

Recent Submissions

Embargo
Energetic Materials for Biological and Electronic Applications
(2025-09) Ostrander, Eric
Conjugated polymeric materials represent a promising next step for electronic applications. As organic semiconductors (OSCs), they offer key advantages over their inorganic counterparts, including solution-processability, mechanical flexibility, and compatibility with low-cost fabrication techniques. To enable efficient charge transport, OSCs typically require doping to generate charge carriers. However, this creates instabilities and changes within the material. In this dissertation, I investigate the doping mechanism of an n-type dopant and in parallel, I explore strategies to improve charge transport in amorphous p-type conjugated polymers, where disordered morphology poses a significant challenge. Additionally, I examine a biological application that employs abiotic triphosphate compounds to modulate muscle function, expanding the potential of synthetic systems in bioelectronic contexts. Collectively, this work advances the understanding of doping mechanisms in n-type polymers and proposes new methods to enhance electrical performance in disordered systems, paving the way toward cost-effective synthesis and broader application of conjugated polymers.
Embargo
Age Dependent Prefrontal Dynamics of Reappraisal Yield Comparable Cognitive Outcomes
(2025-09) Orlovsky, Irina
Emotion regulation shapes not only how people experience emotional events, but also how those events are remembered, with lasting consequences for behavior and well-being. Reappraisal - the reinterpretation of negative stimuli as more positive – boosts encoding of negative episodes due to a deeper engagement with the meaning of emotional content, while attenuating negative affect over time. Among young adults, reappraisal recruits a distinct network of limbic and cognitive control regions that enhance memory for emotional episodes, thus guiding adaptive resolution of similar negative scenarios in the future. Aging is marked by a greater motivation to regulate emotion and preserve well-being, relative to younger adulthood. Yet, little research has examined if reappraisal reduces negative emotion and enhances memory for negative scenarios in ways that may be similar to -or distinct from- those behavioral and neural mechanisms observed in younger adults. Thus, this dissertation addresses a theoretical gap in clarifying the neural substrates of encoding during reappraisal that support long-term emotional memory in both young and older adults. Twenty young (18-29 years) and 19 older (60-75 years) adults underwent incidental encoding of negative and neutral images during an event-related fMRI scan. Participants either reappraised negative images to reduce negative affect or viewed negative and neutral images passively. Recognition memory for images was assessed in the scanner after a 10-minute (i.e., immediate recall), and 4-hour delay (i.e., delayed recall). Recognition of images did not significantly vary by age group or regulatory condition. However, older adults demonstrated higher recognition sensitivity to neutral relative to negative images. Young adults demonstrated greater relative recruitment of distributed frontal/prefrontal, temporoparietal, and occipital regions to support reappraisal, whereas older adults comparatively relied on a small subset of parietal and posterior cortical regions supporting attentional control and visual integration. In an age-invariant manner, greater prefrontal recruitment predicted worse subsequent recognition accuracy, suggesting a tradeoff between top-down cognitive control and mnemonic efficiency during passive encoding of emotional information. Taken together, these findings reveal neural signatures of reappraisal among both age groups that may interfere with incidental memory encoding for emotional experience and regulation.
Embargo
(De)Centering Whiteness: A Betweener Conversation
(2025-09) Norman-Tichawangana, Verity
Until March 2020, I moved easily and seamlessly between my two roles and contexts that couldn’t be more different: a doctoral student at UMass, Amherst in Amherst, Massachusetts; Executive Director of Jitegemee Children’s Program (Jitegemee), a community development program in Machakos, Kenya. And then the COVID-19 pandemic struck. Flights stopped; work that could, shifted online; we were limited to our homes; travel was out of the question. During the time we were isolated and forced to stay indoors, there was the opportunity for reflection and considering new ways of being. Following the police murder of George Floyd and the summer of 2020 BLM protests, the international development sector had its own overdue moment of reckoning, which led to online conversations, Zoom workshops, media reports and so on and a flurry of anti-racist statements from academic and NGO organizations alike. In this dissertation I use performance autoethnography to offer my embodied critique of an ongoing process of (de)centering Whiteness in my academic scholarship as well as in my work as a development practitioner. That summer, I too was involved in my own personal moment of reckoning as a White development scholar-practitioner, born in apartheid South Africa, working between Kenya and the USA. How could I effectively lead an organization halfway across the world, situated in a completely different context, much less during a global pandemic that rendered visits also impossible? We started considering how we could realize a transition at Jitegemee to ‘local leadership,’ by then a tired sector buzzword that was rarely implemented, in ways that would minimize disruption and harm to the organization and children we supported. This dissertation traces that back-and-forth journey, in community, in conversation, engaged in a process of care and collaboration. I share this dissertation as an offering of love and solidarity; an offering about a process that is incomplete and ongoing. These reflections, our experiences, and challenges with this work, are a snapshot of what I/we did, where I/we were, and how I/we individually and collectively wrestled with the complexities of the on-the-ground, lived realities of what it meant to us to (de)center Whiteness. You are invited to join this journey.
Embargo
Agricultural Context and Bee Health: Assessing Pesticide Exposure and Interactive Effects with Pathogens and Drought
(2025-09) Munoz Agudelo, Deicy Carolina
Pollinators are vital for sustaining biodiversity and global food production, providing essential ecosystem services valued at billions of dollars annually. Yet, their populations have been declining for decades due to multiple, overlapping stressors, including parasites and pathogens, land-use intensification, pesticide use, and climate change. While each of these threats has been extensively studied, their interactive effects on pollinator health remain less understood. In Chapter I explored honey bee pesticide exposure in relation to landscape composition by analyzing honey samples from local beekeepers across the state of Massachusetts, as well as pesticide contamination from commercial wax foundation—a widespread beekeeping practice that mimic natural honeycomb. We found that pesticide concentrations in honey increased with agricultural land cover and declined in areas with more wetlands. Although overall toxicity remained below established thresholds of concern— we used the U.S. Environmental Protection Agency’s acute contact Level of Concern (LOC = 0.4) as a reference (U.S EPA, 2015)—the synergist piperonyl butoxide showed a strong landscape response, with concentration and toxicity both increasing in agricultural landscapes and declining in wetland-rich areas. Additionally, we found that wax foundation itself exposes bees to a wide array of pesticides, representing an often-overlooked contamination pathway. These findings highlight the importance of integrated land management that protects ecosystems such as wetlands to mitigate pesticide exposure, while also rising awareness of the need for wax foundation standards that better support pollinator health. Chapter II examined the effects of chronic, sublethal exposure to three field-realistic concentrations of the neonicotinoid thiamethoxam (0.5, 1, and 1.5 ppb) on Crithidia bombi infection dynamics in lab reared common eastern bumblebee (Bombus impatiens), using both isolated individuals and microcolonies. Elevated mortality occurred only in the individual trials at the highest concentration (1.5 ppb), resulting in its exclusion in the microcolony experiment. While thiamethoxam unexpectedly reduced parasite infection and transmission, it also led to reduced sucrose consumption, impaired mobility, and diminished brood care. These behavioral disruptions may offset any potential benefits of parasite suppression, illustrating the complex and sometimes counterintuitive consequences of interacting stressors on pollinators. Chapter III investigated how drought stress influences neonicotinoid accumulation in the pollen of three major seed-treated crops in the United States: sunflower (Helianthus annuus), squash (Cucurbita pepo), and cotton (Gossypium hirsutum). We also monitored plant performance through weekly growth metrics such as flower production, corolla diameter, plant height, and vine length. Drought consistently reduced floral resource availability but mostly did not affect pesticide concentrations in pollen. Drought did increase detections of thiamethoxam in sunflower, but from a baseline of zero detections in well-watered and moderate stress plants to three very low detections—under the level of quantification—under drought conditions. Across all crops, we detected diverse pesticide mixtures—including insecticides, fungicides, and herbicides—raising concerns about additive or synergistic effects on pollinators. Importantly, patterns of pesticide accumulation differed substantially among crops, emphasizing the roles of crop physiology, pesticide formulations, and environmental context in shaping pollinator exposure risk. Overall, my research demonstrates that pollinator health is shaped by the combined pressures of pesticides, pathogens, and environmental context. These findings underscore the urgent need for integrated conservation and land management strategies that reduce pesticide contamination at its sources, conserve natural habitats such as wetlands, and build resilience in both managed and wild pollinator populations.
Embargo
RADICAL POLYMERIZATIONS IN WATER: EMULSION AND SEMI-BATCH PROCESSES TO YIELD FUNCTIONAL POLYMER PARTICLES AND INTERFACE MODIFIERS
(2025-09) Morgenthaler, Eva
Performing free radical polymerization in aqueous environments is of great interest in fundamental polymer science as well as scalability at the industry level. This thesis focuses on free radical polymerization in water, using techniques of emulsion polymerization and semi-batch polymerization to prepare functional polymer particles and interface-active agents. In the Introductory chapter, Chapter 1, fundamental considerations of free radical polymerization in aqueous media are described. This is followed by the key role of free radical polymerization in heterogeneous polymerization methods, such as emulsion polymerization and the complexities associated with the preparation of functional polymer particles. The focus then shifts to fundamental aspects associated with employing free radical polymerization in “semi-batch” techniques. The introductory chapter is followed by two chapters comprising the core of my thesis research involving free radical polymerization and polymer particles containing neutral, charged or zwitterionic monomers. In Chapter 2, the synthesis of alkyne-rich, patchy polymer colloidal particles is described, using the key synthetic technique of surfactant free emulsion polymerization (SFEP). Polymer colloids synthesized by this technique were subjected to azide-alkyne cycloaddition reactions to alter the functionality on the particle surface and interior. In Chapter 3, the focus shifts to the preparation of hydrophilic polymers containing both charged and uncharged moieties by semi-batch free radical polymerization in water, with the resultant polymers anticipated to serve as useful interface-active agents.

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