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Investigating the Potential for Behavioral Differences Amongst Betta Fish (Betta splendens) Color Morphs
Get PDFSiamese fighting fish (Betta splendens) have been selectively bred for eye-catching color patterns and fin morphologies since the early 20th century. They are a member of the anabantoids, a group of air-breathing freshwater fish possessing a labyrinth organ that allows them to extract oxygen from the air and also influences many social behaviors. Both males and females will flare their gills as a mating behavior. Opercular displays prevent the flow of oxygen across the gills, but the labyrinth organ allows them to continue respiring. We understand B. splendens’ courtship behavior in the wild, but a more concrete understanding of whether or not generations of selective breeding has had a noticeable impact on such behaviors is necessary. Bettas have been an ideal model for applied research in many fields because of their unique morphology, behavior, and evolutionary history. Mate preference is often used to draw conclusions about changes in behavior given particular conditions. Without a reliable understanding of whether farmed and wild betta behavior has diverged, accurate conclusions cannot be confidently made. This study aims to draw definitive conclusions about mate preference behavior and whether color plays a significant role in mate selection. Attributes and behaviors like body size, nest size, and parental behavior all play an important role in mate selection in the wild, but in a lab setting where these factors are controlled, it is necessary to understand where coloration lies in importance for mating. Neither red nor blue females in this study showed a significant preference for males matching their own color or a preference towards red males as a whole. These results call into question the idea that color plays an important role in betta fish mate preference and selection, and thus further research is needed to either support or discredit them
Update on Planned UMS Health Insurance Transition
No full textLast month, we shared that the University of Maine System planned to transition to Anthem Blue Cross & Blue Shield of Maine (Anthem) as our health insurance administrator, effective Jan.1, 2026.
As we also noted, Anthem was selected through a transparent, competitive procurement process in which they received the highest evaluation score.
Since that decision, Anthem’s contract negotiations with Northern Light Health (NLH) — a key healthcare provider for some of our covered employees — have reached an impasse
University of Maine System Student Conduct Code, 2025
No full textThe Student Conduct Code (“Code”) is a requirement under the University of Maine System (“University”) Board of Trustees Policy Section 501 and exists to notify students, faculty, and staff of the specific expectations the University holds related to student behavior and the rights and responsibilities that accompany being a student and participating in student activities and organizations. The University expects students to maintain standards of personal integrity in harmony with its educational goals; to be responsible for their actions; to observe national, state, and local laws and regulations, and University rules and policies; and to respect the rights, privileges, and property of others
Quality Assessment and Shelf life Study of Maine Wild Blueberries
No full textWild blueberries (Vaccinium angustifolium Ait. And V. myrtilloides Mitchx.) are a lowbush fruit crop native to North America and a cornerstone of Maine’s agricultural economy, contributing over 95% of U.S. production. Valued for their intense flavor, high anthocyanin content, and associated health benefits, they are predominantly marketed frozen, with fresh berries comprising only ~1% of sales due to their short postharvest life. Limited research exists on the shelf life of fresh wild blueberries, particularly under commercial handling and storage conditions. This study assessed the quality and shelf life of fresh wild blueberries harvested from three commercial farms in Maine, with the aim of identifying key factors influencing deterioration and providing recommendations to extend market availability.
Over the 2023 harvest season, fruit was collected from farms A, B, and C, sorted, and stored under controlled conditions. Quality assessments were conducted at multiple storage intervals (0–21 days) using physicochemical measurements such as °Brix, pH, moisture content, and weight loss, alongside microbial analyses for yeast and mold counts. Farm origin and storage duration were treated as primary variables. The impact of mechanical damage was also evaluated, with drop height during harvest and packing line processing noted as potential contributors to bruising and subsequent decay.
Results indicated that storage time and farm origin significantly influenced most quality parameters. °Brix values remained relatively stable in early storage but declined after day 15, suggesting sugar metabolism during respiration. pH increased gradually, particularly in later storage, correlating with a perceived loss of flavor intensity. Moisture content and firmness decreased steadily across all farms, with higher rates of weight loss observed in berries from farms with lower initial moisture levels. Mechanical damage was linked to accelerated softening and increased susceptibility to fungal colonization. Microbial analysis revealed that yeasts were the predominant spoilage organisms, proliferating rapidly under conditions of high moisture and mechanical injury, while mold incidence increased notably after day 12 at 4 °C storage.
Differences between farms were attributed to variations in genotype composition, field management practices, and harvest handling. Farm A berries exhibited the lowest weight loss and maintained firmness longest, while farm C berries showed the highest microbial counts by mid-storage. Across all farms, maintaining storage at 4 °C with relative humidity between 90–95% significantly slowed deterioration compared to ambient storage.
This study confirms that the perishability of fresh wild blueberries is driven by a combination of physiological and microbial factors, compounded by handling-induced damage. Effective interventions include rapid postharvest cooling, minimizing drop heights during mechanical handling, and exploring advanced packaging technologies such as Modified Atmosphere Packaging (MAP) to slow respiration and microbial growth.
By establishing baseline shelf life data and identifying critical control points in the postharvest chain, these findings address a key knowledge gap for Maine’s wild blueberry industry. Adoption of improved postharvest practices could expand the fresh market share beyond the current 1%, potentially increasing economic returns for growers and providing consumers with extended access to high-quality fresh wild blueberries
Analysis of Material Properties in Binder-Jet Additive Manufacturing
No full textThis work explores binder-jet printed parts’ material properties with regard to their application to simulation. The objective of this work is to establish a more diverse selection of experimental methods used to characterize binder-jet printed material’s bulk properties, leading to more accurate modeling.
The results of density and surface roughness measurements are discussed along with their implications. Samples of binder-jet printed material were scanned by X-ray profilometer to determine their density and examined using optical microscopy to determine their surface roughness. Density of printed sand samples was found to vary based on part orientation relative to the travel direction of the printer recoater. Surface roughness was found to be influenced by multiple factors (part orientation relative to printer x- and y-axes, face orientation relative to the vertical, etc.), each changing the surface roughness by up to 13%.
The results of various thermal analyses of both raw silica foundry sand and a mixture of silica foundry sand with proprietary binder used in a commercial binder-jet printer are presented. Silica foundry sand was examined to provide a baseline for the binder-jet printed material. Thermogravimetric analysis of the sand-binder mixture gave indications of the decomposition of the proprietary binder at temperatures commonly seen in metal casting, a key application for binder-jet printed material. Transient Plane Source measurements provided an indication of the thermal diffusivity of the binder-jet printed material at room temperature. Differential Scanning Calorimetry measurements provided indication of the specific heat capacity of the sand-binder mixture. At low temperatures, sand and the sand-binder mixture were demonstrated to have similar specific heat capacities.
A macroscopic experimental method to measure bulk thermal properties of binder-jet printed material is presented along with the results of experiments performed with this method. Printed samples were instrumented and then heated in a custom-built furnace; the temperature of the samples at select radii were recorded and analyzed. The Fourier analysis method is used to determine the specific heat capacity and thermal conductivity of the binder-jet printed material from these temperature measurements. These resulting material properties were applied to a simulation of the experimental method. While thermal analyses agreed broadly with the experimental method’s analyzed results, the experimental method and the simulation results did not.
The shortcomings of the thermal analyses, macroscopic experimental method, and accompanying simulation are presented, along with suggestions for improvements to the experimental method. Follow-on work can use this work’s methods and results to provide more realism in modeling casting events
Simulated Atmospheric Composition and Structure of Earth-Like Exoplanets
No full textThe characterization of exoplanets is a computationally demanding undertaking. We show how confirmed exoplanets can be investigated using atmospheric models and spectra from the Python package petitRADTRANS (pRT). We find that the four Earth-like exoplanets in this study (K2-72 e, Kepler-1649 b, Kepler-1649 c, and TOI-700 e) are seemingly hot worlds with surface temperatures ranging from 600 - 800 K. We also investigate possible compositions of each atmosphere and find from our models that they appear to be hydrogen-dominated, with trace amounts of He, H2O, CH4, H2S, PH3, and NH3. The transmission spectra plots show inflated transit radius values, and from this, we estimate atmospheric depths of the exoplanets to range from 441 - 4428 km. We see that optically active chemical species contributing significantly to the transmission spectra in the infrared wavelength are H2O, H2S, and NH3. The results in this study are intended to be used as a baseline argument for potential further observations
The Politics of Disposable Packaging: An Ethnographic Analysis of Extended Producer Responsibility (EPR) Policies in the United States and Canada
No full textRecent disruptions in global recycling markets and growing environmental and health concerns surrounding plastics have ignited renewed interest in packaging waste management. Questioning the viability of the current recycling system to contend with the ever-growing disposable packaging waste stream, policymakers are increasingly turning to circular economy policies such as Extended Producer Responsibility (EPR). EPR holds producers accountable for their products’ end-of-life management. The underlying assumption is that greater responsibility will incentivize producers to reduce costs by designing more environmentally friendly packaging. Despite EPR schemes existing for decades and increasing recycling rates, little evidence suggests they are driving upstream design changes. Moreover, environmental justice advocates are concerned that industry will co-opt EPR policies to advance chemical recycling technologies that disproportionally harm low-income communities and communities of color. Addressing the lack of research on the justice implications of circular policies, this dissertation explores the shifting geographies of power, equity, and access as packaging materials are re-valued.
As new circular economy policies emerge across North America, this dissertation examines the politics around disposable packaging, analyzing how packaging EPR policy is conceptualized, negotiated, and contested across time and space. Specifically, I examine how the new measurement systems emerging in these policies are negotiated, paying attention to the ways in which power relations are disrupted or reproduced. The dissertation draws on 24 months of ethnographic research, including event ethnography, a Delphi survey, public discourse analysis, and interviews. Two qualitative case studies (in Maine and Ontario) examine these debates around packaging and their potential environmental justice implications.
Overall, this research extended theories around power, knowledge, and action in environmental policy. It contributes to discard studies by challenging common understandings of waste, disposability, and circularity. In addition, this study contributes to theory in the anthropology of policy by exploring how trust and transparency shape calculative practices within neoliberal market-based approaches to environmental governance. This research has practical implications for policymakers and waste managers seeking more effective and just policies. Waste laborers, frontline workers, and fence line communities should be included in the design of EPR programs to avoid simply shifting the environmental and socio-economic burdens of packaging elsewhere
