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LINKING JUVENILE RIVER HERRING GROWTH, DIETS AND HABITAT USE IN FRESHWATER AND ESTUARINE ENVIRONMENTS
No full textAlewife (Alosa pseudoharengus) and blueback herring (Alosa aestivalis) populations, collectively “river herring”, have declined drastically over the last century due to overfishing, habitat degradation and impediments to migration. River herring provide critical ecosystem services in coastal watersheds, serving as forage for a wide variety of predators and as a link between marine and freshwater environments where adults import marine nutrients into freshwater lakes and their offspring export nutrients from freshwater back into the ocean. The factors driving young-of-year river herring productivity are not well understood, but are important for restoring populations and their critical ecosystem services. Although recent work in coastal New England has focused on estimating metrics of juvenile productivity in freshwater lakes, there are significant data gaps associated with the habitat use, growth rates, and survival of juvenile river herring as they migrate from freshwater to estuarine habitats. The first empirical study in this thesis examined juvenile growth rates across freshwater lake, river, and estuarine habitats within three coastal Massachusetts watersheds. Results suggested that access to downstream estuarine habitats provides opportunities for enhanced juvenile growth rates compared to lake-resident fish, particularly in systems with high in-lake juvenile densities and unimpeded connectivity to the estuary (e.g., Weymouth Back River watershed). In high-density systems with multiple barriers to downstream fish passage (e.g. Mystic River watershed), bottlenecks to juvenile growth may occur when high densities of emigrating fish occupy shallow, eutrophic river reaches. In contrast, in low-density systems, juvenile growth rates were similar between lake and estuarine habitats (e.g., Essex River watershed). Juvenile river herring that remain in freshwater lake habitat in high-density nursery environments are also faced with density dependent growth limitations due to low pelagic prey biomass. The second empirical study in this thesis explored dietary composition, prey selectivity, morphological traits, and growth in littoral and pelagic lake habitats across four sites. Stomach content and environmental zooplankton analyses revealed flexible foraging strategies within and among populations, where juvenile river herring engage in pelagic filtering, benthic or epiphytic foraging, and surface feeding depending on habitat and prey availability. Alewife generally selected larger prey, although they also exhibited signs of intraspecific resource partitioning in Great Herring Pond, a high-density system. In Upper Mystic Lake, where blueback herring and alewife co-occur, alewife primarily exploited littoral prey while blueback herring targeted more pelagic zooplankton, highlighting species-specific niche differentiation. These findings underscore the ecological importance of littoral habitats in lakes and the value of preserving habitat complexity and connectivity across freshwater and estuarine nursery environments. Moreover, this research provides novel insights into the mechanisms driving juvenile river herring production and offers practical guidance for protecting access to quality nursery habitats that will maximize juvenile river herring growth and survival.Master of Science (M.S.
The Meaning is as Fragile as the Flesh Between Us.
No full textThe following works explore meaning making and identity formation through written, spoken, and visual language. Starting from my own bi-cultural experience as a second generation Lebanese American, I examine what it means to be cut off from my family's languages and accents and how that has impacted the ways I have been able to engage with my culture(s) and the family mythologies and histories that have shaped who I am.
Stuart Hall says that “Culture is about ‘shared meanings’.” It is from this standpoint that I set out to discover the myriad meanings that have been missing from my understanding. Years of cultural assimilation and linguistic imperialism have altered the ways that I am able to verbally engage with my Lebanese family and the American culture I was brought up in; this is the experience of being neither here nor there, always hovering somewhere inside the dense fog we call identity.
This project is framed around my experience as an English only speaker who grew up watching, in real time, the ways cultural assimilation worked quickly to erase the Levantine Arabic language that arrived with my paternal family when they emigrated from Lebanon in the 1970’s, and how accent bias worked to delete the nuanced Appalachian English that my maternal family brought to Massachusetts from the mountains of West Virginia.
Through the use of text, projections, collaged elements, shadow boxes, photography and translated song lyrics, I attempt to grasp the diaphanous meanings and accents that have been redacted from the mouths and memories of my family using the New England English language I am fluent in.Master of Fine Arts (M.F.A.
Toward Sovereignty-Centered Forest Management: A Review of Participatory and Indigenous Research Frameworks for Tribal Forest Stewardship
No full textUSDA Forest Service, Northern Research Statio
A Case for COUNTER
No full textIn the modern library landscape digital assets have become a critical component of our collections. Usage data and statistics have become more and more relied upon in the decision-making
process of collection development. Thinking about my position as a Collection Analysis Librarian at the University of Massachusetts Amherst, having reliable and trusted data and standards at our
disposal is crucial for ensuring our patrons have the material they need for their research as well as for evaluating financial constraints and impacts of supporting the variety of resources we have
Defusing Workplace Urgency: Staying Grounded, Setting Boundaries, and Getting Your Work Done
No full textSince COVID-19 shutdowns swept the globe, and permanently altered the work of academic librarians, the concept of a “workplace emergency” has taken on new weight. With the pandemic behind us, but the repercussions still very much part of our day-to-day experiences, we can struggle to discern a work crisis from an unpleasant email. The service ethos of our profession compounded with our socio-political landscape pressures many librarians to work constantly and perfectly. As a result, our nervous systems are in disarray, and work can feel like a battleground. In this workshop, we will explore the concept of urgency and how it shows up in the workplace, specifically for academic librarians in a faculty and / or student-support role. We will unpack different types of urgency and the cultural contexts that exacerbate them. In small groups, participants will deconstruct common workplace situations, create strategies to set boundaries, and clarify their work foci to set boundaries so their jobs can be manageable. Attending with department colleagues is encouraged. Participants will leave the workshop with a set of practical tips and a sense of permission to de-escalate their work lives and (re)claim professional agency
The impact of the ROTEL project on student learning and feelings of inclusion
No full textThe Remixing Open Textbooks through an Equity Lens (ROTEL) project promotes textbook affordability, student success, and inclusion and equity to benefit all students, particularly those from minoritized populations. To date 22 books have been published. The assessment coordinators for the ROTEL project, will share the results of three semesters of data collection investigating the impact of using an intentionally designed inclusive textbook on student success and feelings of representation and belonging. They will share data that compares grade outcomes and course completions for students enrolled in course sections that used a ROTEL textbook versus those students enrolled in sections that did not use a ROTEL book. They will also share survey results on students’ perceptions and experiences using these textbooks
Towards Encrypted Network Traffic Analysis
No full textTraffic analysis aims at extracting sensitive information from network traffic patterns, in particular in scenarios where network traffic is encrypted. Traffic analysis has been used to compromise anonymity in anonymous communication systems through various types of attacks, specifically, website fingerprinting (WF), and flow correlation. In this thesis, we explore two approaches to performing traffic analysis on encrypted network traffic: a model-based approach and a data-driven approach.
The model-based approach focuses on establishing statistical models for traffic characteristics which are used to design effective traffic analysis algorithms. We perform model-based traffic analysis on popular Secure Instant Messaging (SIM) applications. Despite using advanced encryption algorithms, such services do not utilize sophisticated obfuscation algorithms and traffic analysis attacks can infer sensitive information from their traffic patterns. In more dynamic and complex systems such as Tor, general-purpose statistical algorithms cannot capture the nature of noise. Hence, we study a second approach, called data-driven. In this approach, we use Deep Neural Networks (DNNs) to design a flow correlation system called DeepCorr to learn a correlation function tailored to Tor's ecosystem.
To mitigate the aforementioned traffic analysis attacks, we investigate different countermeasure techniques. First, we apply obfuscation-based algorithms to both model-based and data-driven approaches. However, normal obfuscation techniques such as delaying packets, are not effective against DNN-based traffic analysis attacks. Therefore, we propose a second defense mechanism based on adversarial examples which are known to degrade the performance of DNNs.
Although data-driven based traffic analysis algorithms show promising performance, they often lack practical assumptions making them infeasible for real-world. In this thesis, we identify the root cause of such impracticality issues: the attacker's lack of a longitudinal perspective into network traffic during training of WF classifiers. We show that such impracticality issues can be alleviated by augmenting the network traces used to train WF classifiers. Specifically, we introduce NetAugment, an augmentation technique tailored to the specifications of Tor traces. We instantiate NetAugment through semi-supervised and self-supervised learning techniques. Our extensive open-world and close-world experiments demonstrate that under realistic evaluation settings, our WF attacks provide superior performances compared to the state-of-the-art; this is due to their use of augmented network traces for training, which allows them to learn the features of target traffic in unobserved settings (e.g., unknown bandwidth, Tor circuits, etc.).This dissertation is supported by
- NSF grants CNS-1525642, CNS1553301, CNS-1564067
- DARPA and NIWC under contract N66001-15-C-4067
- NSF grant CNS-1953786,
- The Young Faculty Award program of the Defense Advanced Research Projects Agency (DARPA) under the grant DARPA-RA-21-03-09-YFA9-FP-003Doctor of Philosophy (Ph.D.)2026-05-1
The Unintended Consequences of National Office Consultations and Auditor Decision Attribution on Auditor Client Negotiations
No full textNational office consultations are an important aspect of the audit process and allow for engagement partners to obtain some additional assurance when faced with complex accounting or audit issues. The outcome of the consultations, however, can be unfavorable to the client and result in difficult conversations between the audit team and the client. I investigate how the type of national office consultation and the engagement partner’s communication of difficult news to the client affects the auditor-client relationship, as well as the outcome of discussions between the auditor and client regarding financial statement adjustments. I make predictions based on two competing theories, and find evidence showing that client concessions are being driven by trust and perceived credibility. I find that when a consultation is optional and the engagement partner takes greater (less) responsibility for the outcome of the consultation, clients will make smaller (larger) concessions during the discussions with the auditor. In contrast, when the engagement team engages in a mandatory consultation, I find that this pattern reverses. I also provide evidence that this effect is mediated by trust in the engagement team and perceived credibility of the national office. I discuss the relevant takeaways of these findings for theory, literature, and practice.Doctor of Philosophy (Ph.D.)2026-05-1
LEARNING FROM AFFILIATIONS: OVERCOMING CHALLENGES OF NEW BUSINESS DOMAIN
No full textOrganizational scholars have long posited that business firms are, in essence, learning entities. This is because firms must learn to adapt and survive in the domains in which they operate. In familiar and stable environments, firms leverage their previous experiences to improve their routines and operational efficiencies. Familiarity with and stability of the external environment allow firms to incrementally build on their existing know-how. However, learning from prior experiences is not usually sufficient when the external environment is dynamic and existing routines are subject to rapid obsolescence. Prior experience is also of limited use when the firm extends the scope of its operations into unfamiliar domains where it lacks the know-how necessary for success.
So, how do firms learn when they enter a new domain of operations? How does their need to learn and adapt to the new domain interact with the need to continue learning in the primary domain? Furthermore, what challenges do firms face when both the primary and new domains are subject to rapid change while being vastly different?
I examine these and related questions in this dissertation. Drawing upon the existing organizational learning theories, I develop a theoretical model to outline the mechanisms that allow focal firms to succeed in the new domain while continuing to perform to expectations in their primary domain. In the main, I argue that when entering a new domain, firms rely significantly on vicarious learning from specialist organizations that are already steeped in the complexities of that domain. Such reliance on external parties allows the focal firms to continue to develop in their primary domain while also becoming familiar with the imperatives of the new domain and, over time, to develop new processes and routines necessary for success.
After reviewing the relevant literature and developing a theoretical model, I empirically examine my theory with a sample of technology firms that entered the capital markets through an Initial Public Offering. These firms face challenges due to their limited experience in the capital markets. Moreover, they must continually improve their operations in their primary product-market domain to remain competitive in a rapidly changing technological landscape. As such, my central thesis is that the survival and performance of technology firms post-IPO depend on their ability to learn and adapt to the changing dynamics of the capital markets and the operational environment. To test my hypotheses, I use a longitudinal sample of high-technology firms. The sample comprises Initial Public Offerings (IPOs) from 1990 through 2022. I have created my final dataset by combining SDC-Platinum, Compustat, and CRSP data. I use a discrete-hazard model and regression analyses.Doctor of Philosophy (Ph.D.)2026-05-1