ScholarWorks@UMassAmherst

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Graduate students: Directions for submissions can be found in this guide. Please email scholarworks@library.umass.edu if you have any questions.

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Please see our ScholarWorks guide for more information about submitting your work to ScholarWorks.

Featured Items

Data Do's and Don'ts: A Primer on Indigenous Data Sovereignty

Anderson, Jane; Smith, Vanessa

2026

A Mighty Event: Eight Lessons Learned by Bringing People Together Through Music to Support Our Mission

White, Caroline J.; Fill, Kim D.

On the evening of November 7, 2025, the University Libraries at the University of Massachusetts Amherst held its annual Fall Reception, attended by an audience of 300. “An Evening with Folk New England: A Tribute to Eric von Schmidt” represented both a return to the longstanding tradition of an event held to showcase the Libraries while thanking our donors for all they make possible and an exceptionally successful and memorable version of that event. Celebrating the partnership of Folk New England and the Libraries' Robert S. Cox Special Collections and University Archives Research Center, the event generated so much interest that it was ultimately moved to a larger venue, and the move impacted all aspects of the event. Although the planning team cannot count on replicating the event or its impact in the near future, the team took away many lessons from the planning and pivoting, as well as from the event itself.

2026-03-19

Regional Invasive Species & Climate Change Research to Practice Paper: Rock you like a hurricane: The perfect storm for an invasion

Putnam, Aly B.; Al-Shayeb, Sofia M. A.; Buonaiuto, Daniel M.; Daniel, Wesley; Geiger, Megan Lynn; Lieurance, Deah; Parsons, Elliott W.; Pfingsten, Ian; Williams-Soriano, John Paul; Evans, Annette E.

Hurricanes (also called typhoons or cyclones) and other rare weather occurrences are increasing in intensity and frequency with global climate change. These extreme weather events can drastically alter ecosystems in ways that directly or indirectly facilitate the introduction, establishment, spread, and impacts of invasive species. For example, high winds or flood waters during hurricanes can disperse invasives and displace native species. Impacts could also occur after the main storm event; invasive species can invade during relief efforts or establish more easily in disturbed habitats [1,2]. Various possible mechanisms link hurricanes and invasive species (Figure 1). To identify shared challenges as well as region-specific dynamics and possible impacts, we highlight case studies from the Southeast, Pacific Islands, Caribbean, and Northeast regions of the United States (Table 1). By synthesizing examples across diverse ecological and management contexts, this summary can help practitioners anticipate common mechanisms of spread and consider strategies that could be implemented before and after hurricane events to manage vulnerable species, habitats, and ecosystems.

2026

Recent Submissions

Open Access
IRREDUCIBLE GEOGRAPHY AND NIELSEN REALIZATION IN DIMENSION 4
(2026-02) Arabadji, Mihail
This thesis contains results on the geography of 4-manifolds and the Nielsen realization problem in dimension 4. In the first part, we construct smooth manifolds with order two π1 and even intersection forms that are irreducible, meaning they do not decompose into non-trivial connected sums. Their intersection forms being even implies that their universal covers admit spin structures. Such manifolds are determined up to homeomorphism by their Euler characteristic e, signature σ, and whether they themselves are also spin. In the case that the manifold is spin, we construct irreducible manifolds for all but 17 realizable coordinates in the region of the (e, σ)–plane with c21 = 2e + 3σ ≥ 0 up to orientation. In the case that the manifold is non-spin, we construct irreducible manifolds for all but 24 realizable coordinates in the region of the (e, σ)–plane with σ/8 < −8 and c21 /4 > 9, again up to orientation. We construct these manifolds by taking equivariant fiber sums of Lefschetz fibrations and other symplectic manifolds which are simply–connected and spin. Along the way, we develop machinery to track when the spin structure is preserved during these operations. In the second part, we show that the Nielsen realization problem fails; namely, there exist finite subgroups of their mapping class groups that cannot be realized by any group of diffeomorphisms. This extends and complements recent results for spin 4–manifolds. Our examples span virtually all possible intersection forms, both even and odd, indefinite and definite, and include many irreducible 4–manifolds. To derive these examples, we study multi-twists, projective twists, and multi-reflections, which are all mapping classes supported around collections of embedded spheres and projective planes. Our obstructions to Nielsen realization are based on the work of Konno. We investigate projective twists in further detail, and notably, employ them to show that, for many closed symplectic 4–manifolds, the symplectic Torelli group is not generated by squared Dehn twists. In addition, we provide an example when the mapping class group contains a subgroup isomorphic to a symmetric group. Both parts of the thesis revolve around several common ideas. Firstly, mapping class group is in the statement of Nielsen realization and is used extensively in the constructions of our geographies by building blocks of Lefschetz fibrations which are determined by monodromies described by mapping class groups of surfaces. Secondly, in both problems we fill geographies of 4-manifolds in particular both of them involve plenty of constructions. And thirdly, all constructions are either spin or have spin universal cover which is particularly exciting since spin manifolds are scarce.
Open Access
Visioning within (and beyond) a secondary-level ethnic studies program: A site of hope, aspirations, tensions, and critique
(2026-02) Arce, Joel
As public schools increasingly begin to offer ethnic studies coursework, it is crucial to examine the ways ethnic studies is described, implemented, and evaluated. The more recent expansion of K-12 ethnic studies primarily stems from grassroots-driven campaigns; however, these efforts coincide –and sometimes coexist– with top-down mandates at the state or district level. Therefore, research should not be confined to curriculum-based inquiries; instead, research should broadly explore how schools and educators engage with the pedagogical commitments of ethnic studies and its reframing of education. The ethnographic research informing this dissertation situates the experiences, narratives, and institutional policies and practices surrounding a secondary-level ethnic studies program, Canal City Public Schools Ethnic Studies (CES), within the larger K-12 ethnic studies movement. Given my relationship as a collaborative researcher-practitioner to the CES program, I had multiple entry points to gather data for this ethnographic study. These entry points include classroom visits and program visioning sessions, as well as co-facilitated teacher professional development meetings, community advisory board meetings, and after-school leadership programming with/for students. My field data collection covers a nearly seven-year timeframe between 2016-2023 and encompasses context-specific discussions and experiences related to a wide range of topics. Building on my methodological commitments that span critical theory, constructivism, and participatory action research paradigms, I relied on case study procedures to structure the design of my broader ethnographic research and data collection efforts. For the purposes of this dissertation, I present two standalone manuscripts that emerged from this broader ethnographic case study and serve as examples of my participatory research at CES. The themes that surface in these manuscripts illustrate some of the contradictions, challenges, and possibilities that arise when educators and community partners implement a vision for a critical ethnic studies program within a public school district that purports itself to be carrying a banner for equity and culturally responsive education.
Open Access
A Journey Through Unusual Genomes: Unraveling Genome Architecture, Genome Dynamics, rDNA Organizations, and Chromosome Rearrangement Patterns in Ciliates
(2026-02) Ahsan, Ragib
Ciliates are an ancient clade (~ 1 billion year) of single-celled microorganisms that are nested within the eukaryotic tree of life. They have been serving as models for genomics studies for over a century. The key characteristics used to identify ciliates are their hair-like cilia, and their dimorphic nuclei; ciliates contain both somatic macromoleculei (MAC- highly polyploid, contains gene sized chromosomes, and transcriptionally active), and the germline micronuclei (MIC- diploid, harbors repetitive DNAs, and carries the genetic information to the next generations) within the single cell or individuals. Although each ciliate individual contains at least a somatic macronuclei, and a germline micronuclei, the number of the MACs and MICs with different types of patterns within each ciliate cell varies among the species. These nuclear features are connected with their genomic features. Somatic macronucleus are usually developed from the germline micronucleus through nuclear rearrangements (nuclear development): the micronucleus undergoes mitotic division and one zygotic daughter nuclei goes on to become the new, fully developed somatic macronucleus following a series of DNA deletions, rearrangements, and amplifications, while the other becomes the micronucleus. Studies have largely focused on the model ciliates such are, Tetrahymena, Oxytricha, Paramecium, and Euplotes. The structure, organization, and architecture of the genomes of these model lineages are well explored because they are easy to culture. However, there are many other ciliate groups (non-model) that have not been studied to the same extent. The main focus of this dissertation is on the somatic macronuclei and the germline micronuclei in uncultivable ciliates, where the overall goals are to understand their nuclear architecture, and the genome dynamics: genome architecture, ribosomal DNA (rDNA) organization, and evolution of their genomes; and mitochondrial DNA (mtDNA) structures with any differences within their germline genome sequences. This work combines microscopy (light, fluorescence, and confocal microscopy), single cell ‘omics (both genomics and transcriptomics), and bioinformatic analyses to answer the research questions. This research work solely focused on the Phyllopharyngean (Chilodonella sp.), and Spirotrich (Tintinnopsis sp.) ciliate groups. Chilodonella are usually available in the lakes, ponds, and creek ecosystems where they survive by foraging bacteria and other microbes. Although some species of Chilodonella are known as parasites, the Chilodonella species that were the focus of this dissertation work are free living. On the other hand, Tintinnopsis ciliates are very commonly available in salt water. They could also be found in the fresh water, but they are more abundant in salt water than the freshwater habitats. In the first chapter (Introduction) of this dissertation, the single-celled microorganisms that are the main focus of this doctoral thesis work are introduced. This chapter mainly discussed somatic macronuclei, and their size variation (diversity) in different ciliate lineages, described DNA content at different MAC developmental stages, and explained germline-somatic genome rearrangements. Overall, based the literature review set the stage for this thesis work. The second chapter explored the architecture of somatic macronuclei, and the genome dynamics in non-model ciliates, Chilodonella uncinate. This is the only portion of this dissertation where the clonal line of this freshwater ciliate was used. This chapter investigated the nuclear developmental stages using DAPI (4′,6-diamidino-2-phenylindole) staining and FISH (Fluorescence in Situ Hybridization) technique. The major findings from this study includes: (i) the strategy of maintaining the genome dynamics in these non-model ciliates are different from the well-studied model ciliates. Additionally, an updated nuclear cycle in Chilodonella uncinate was proposed based on the observations from this study. In the third chapter of this dissertation work, genome architecture, and rDNA organization patterns in uncultivable Chilodonella lineages are investigated. In this portion of investigation, a palindromic rDNA in their somatic genomes is described, which is the first time description of a palindrome in this ciliate group. Moreover, the germline rDNA locus in two Chilodonella ciliate isolates is characterized, and the bioinformatic analyses proposed there is possibility of being cryptic species in these two isolates. The final chapter (fourth chapter) includes a pilot study. In this part of this dissertation research, the mitochondrial DNA structures and differentiation in the germline limited sequences within the Tintinnopsis cylindria ciliates is explored. This study reveals that the mitochondrial genomes in this ciliate group are identical based on the partial mitochondrial genome sequences we could retrieve from our data. Note that, this mitochondrial genome data is presenting for the first time in this marine Spirotrich ciliates group. Additionally, the germline genome sequences that recovered from ten Tintinnopsis cylindrica ciliate species were also compared in this study. This showed a tremendous variation between their germline genomes. Overall, this doctoral dissertation will expand the scientific knowledge on the unusual genomes, and the genomic features in the non-model ciliates that leads towards evolution.
Open Access
Practical Advances in Modern Cryptographic Primitives
(2026-02) Acharya, Ojaswi
Modern cryptographic primitives have evolved from supporting basic to more advanced functionalities, and such schemes are now getting more practical. In this thesis, we identify and rectify some limitations of such cryptographic constructions and their proofs of security. Specifically, we work with functional encryption, secure aggregation, and threshold signature schemes, and observe key functional or security limitations in prior work. Our first focus is functional encryption (FE), which enables function evaluation on encrypted messages using a functional secret key. A different primitive named function-revealing encryption (FRE) allows one to compute a fixed function of the underlying messages using their ciphertexts only. We give formal definitions and construct an inner-product FRE scheme. We also analyze the relationship between FE and FRE. Our second contribution considers secure aggregation, a classic problem that has numerous applications in privacy preserving machine learning. Secure aggregation lets many clients contribute data for aggregation without revealing their individual data. Existing practical protocols either have multiple rounds of interaction between clients and the server or rely on heavyweight cryptographic primitives. We build a non-interactive secure aggregation protocol using a novel combination of inner-product FE and a fully-linear probabilistically checkable proof (FLPCP) system. For this protocol, we use an existing FLPCP system [BBCGI’19] that we prove satisfies soundness and zero-knowledge properties even when reused for multiple proof instances. Finally, we address a pressing open question: achieving fully adaptive security for the Sparkle+ [CKM’23] threshold signature scheme. Threshold schemes require t signers to provide partial signatures to form a valid one. Fully adaptive security prevents adversaries from forging signatures even when corrupting up to t-1 signers. While Sparkle+ is secure against static corruption and a limited number of adaptive corruptions, a previous proof of fully adaptive security was shown to be incorrect. We propose a novel hardness assumption under which Sparkle+ satisfies this notion with a tight reduction. We establish hardness of this assumption in the elliptic-curve generic-group model. Our contributions close important gaps in prior work and push advanced cryptographic primitives closer to practice.
Open Access
AI-DRIVEN NETWORK SLICING IN MULTI-DOMAIN MULTI-TECHNOLOGY WIRELESS NETWORKS
(2026-02) Abdelhafez, Haitham
The rapid advancement of wireless networks and the Internet of Things (IoT) has enabled applications such as smart cities, AR/VR, eHealth, and intelligent vehicles, all requiring seamless connectivity, computing, and content distribution. These applications demand adaptive resource management and dynamic orchestration across heterogeneous environments. Network slicing (NS) has emerged as a key enabler, allowing shared infrastructures to support multiple service classes through isolated virtual networks that guarantee specific service level agreements (SLAs). However, orchestrating communication and computing resources across the fog/edge/cloud continuum introduces significant challenges in multi-domain coordination, uncertain resource allocation, security, and SLA sustainability under dynamic network conditions. To address these issues, we develop a self-learning, multi-mode network slicing mechanism for dynamic multi-tier and multi–radio access technology (RAT) networks, which adapts to network conditions and minimizes SLA violations. Our framework enables timely data collection across heterogeneous IoT systems (e.g., WiFi, Cellular, Zigbee, LoRa) through an SLA decomposition and orchestration scheme that supports collaboration across administrative domains. We further extend this design to satellite–terrestrial integration, proposing a belief-based optimization algorithm that jointly optimizes slice configuration, routing, and resource allocation. While network slicing enables customized virtual networks, ensuring covert communications—where transmissions remain undetectable to adversaries—remains largely unexplored. To this end, we introduce Covert Multi-RAT Network Slices (CM-RATNS), a unified framework enabling covert communication across multi-RAT IoT systems. Through coalition-formation mechanisms and edge-enabled coordination, CM-RATNS jointly optimizes resource utilization, cost, and covertness, enhancing covert throughput, energy efficiency, and secrecy. Evaluation results demonstrate that our proposed schemes significantly outperform existing approaches in utility, secure data offloading, and SLA robustness, paving the way toward intelligent, secure, and adaptive 6G network slicing.

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