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Exploring the intersection of open education and open science: Building a network of people, projects, and protocols to support effective undergraduate biology education.
No full textLeveraging open science resources (data, tools, literature, communities, etc.) to support student-centered learning environments is emerging as an important education reform strategy in undergraduate biology. The BioQUEST Curriculum Consortium is hosting a Research Coordination Network that brings together diverse stakeholders representing the breadth of both the Open Education (OE) and Open Science (OS) communities to highlight existing work at the intersection of OE and OS, explore strategies for supporting FAIR (Findable, Accessible, Interoperable, and Reusable) principles in the curation of those resources, and address barriers to equitable participation in their use. This introduction to the Network will provide an overview of our approach to building social and technical connections across these open communities, describe some of the resources available for adoption and reuse, and present a framework designed to support ongoing coordination across the dynamic and emerging landscape at the interface of OE and OS
EVALUATION OF DEFENSE AND ATTACK STRATEGIES FOR CHIPLET-BASED SYSTEMS
No full textIndustry trends are moving toward chiplets as a replacement for monolithic fabrication. A chiplet is a separately-produced silicon die that when packaged together with other chiplets on a silicon interposer creates a system-on-chip (SoC). Chiplets bring about many benefits: they enable IP reuse, allow for heterogeneous integration, and provide the ability to leverage cost-appropriate process nodes, all while decreasing cost and improving manufacturing yield. Yet, creating systems from separately produced components also brings many new security risks to consider, such as the possibility of die-swapping, physical tampering, and probing, which differ greatly from the threat model of a single-die system. As a new technology coming to market, security questions surrounding chiplets still need to be answered. In this dissertation, we evaluate some of the commonly discussed security threats that chiplets face and provide mitigations for them.
Initially, we study a new type of FPGA time-to-digital converter (TDC) sensor for voltage monitoring and side-channel analysis. The sensor described relies on dynamic phase shifting of two clocks and repeated sampling to increase its resolution by 560x and achieve a sub-cycle sampling time. We demonstrate its capabilities by reconstructing the sub-cycle fluctuations in the supply voltage of an FPGA caused by a large number of power wasters activating at the same time during a power attack.
In the second part of this dissertation, we adapt this new sensor to realize a delay-based physically unclonable function (PUF). The PUF derives its uniqueness from the variations in delays of interposer wires routing signals between neighboring chiplets. We find that the output of the PUF provides a unique and reliable fingerprint that can be used to authenticate systems, verify their integrity, and provide active protection against physical tampering and probing. We test our PUF at scale using Amazon’s Elastic Compute Cloud F1 instances and perform analysis to pinpoint the source of its entropy.
Finally, in the last part, we conduct the first documented probing attack against a Xilinx VU9P chiplet-based FPGA. Using the Hamamatsu PHEMOS-X laser probing microscope we employ Electro-Optical Frequency Mapping (EOFM) to locate the interconnect drivers on the FPGA and then follow up with Electro-Optical Probing (EOP) to read out the data they are transmitting. Our findings indicate that probing chiplet interfaces requires significantly less effort than probing internal nodes, thereby highlighting a unique vulnerability of chiplets relative to monolithic integrated circuits (ICs). Furthermore, we deploy two delay sensors, one based on dynamic phase shifting and one that utilizes a TDC, in an attempt to defend against contactless probing. We, however, find that despite being capable of detecting laser probes, delay-based sensors do not offer adequate protection as the change in wire delay is too small to be distinguishable from noise and changes due to localized heating. In lieu, we offer a way of masking bus data to prevent waveform integration and hence data readout.Doctor of Philosophy (Ph.D.)2026-02-0
Slippages of the Collective Present: The Aesthetic and Political Frictions of Oil in the Twenty-First Century
No full textThis dissertation examines literary, cinematic and collective responses to oil from the first two decades of the twenty-first century as they attempt to historicize presents and conceive of futures. This project posits that disparate geographic zones and modes of life are engaged in an act of mutual recognition through oil. Therefore, this project is about the slipperiness and friction caused by oil and the ways in which oil insinuates itself into every aspect of modern life. Situating oil as the medium through which global processes become legible, the works under examination respond to a variety of ecological, historical and narrative imperatives as they enact sites of remembrance that expose the conditions for social exclusion, environmental degradation, and shared complicity. Consequently, this study employs specific case studies that reproduce and disrupt established oil depictions, thus examining the cracks in petroculture.
The first chapter analyzes the political unproductivity of oil through an examination of the overlapping of historical memory and a dissociated witnessing in the waning days of the petrostate as presented in two novels from Nigeria and Venezuela. In the second chapter, I focus on two novels from Argentina and Gabon that choose not to revel in the moment of witnessing but in what comes after as they depict the emergence of toxic communities located at the erratic resource frontiers of oil. Oil as a political actor in a network of labor and consumption is at the crux of chapter three, which examines two films from China and Latvia that contrast an ethics of slowness with petrocapitalism. The final chapter meditates on the political potential of protest as it reconsiders oil as a site of resistance and reimagining in the collective work of Indigenous activists in North America. Using friction as a mode of engagement sets the scope and limits of my project, as friction arises from the assemblage of the selected works, the dialogues each pair represents, their treatment of genre, and the ways they contest established claims surrounding oil culture.Doctor of Philosophy (Ph.D.)2026-02-0
SPECIES RESPONSES TO CLIMATE CHANGE IN COASTAL ECOSYSTEMS: BIODIVERSITY, ADAPTATION, AND THE ROLE OF NATIVE AND INTRODUCED SPECIES
No full textClimate change and biological invasion are among the most significant threats to individual species and collective global biodiversity. Warming temperatures, a key component of climate change, are pushing some species beyond their physical limits. Introduced species, which are continuously rising in number and expanding their geographical ranges, exhibit greater resilience to these environmental stressors. In terrestrial and aquatic ecosystems, generalist introduced species often outperform native species. These patterns remain less explored in marine systems. My dissertation addresses this knowledge gap by comparing the physiological performance of introduced and native marine species and then evaluating their performance under elevated temperatures to determine the impacts of climate change on these dynamics. I also contextualize the occurrence of introduced species occurrence across decadal scales in a marine system, the Boston Harbor, and investigate temporal changes in overall biodiversity associated with climate and other anthropogenic stressors.
In my first chapter, I aimed to better understand the differences in resource use and performance between introduced and native marine species, using two gastropods, introduced Littorina littorea and native L. obtusata as model species. I experimentally determined the grazing preferences of these two snails towards introduced and native macroalgae. I then assessed how their grazing preferences influenced their growth performance.
Building on this foundation, in my second chapter, I investigated how climate change stressors, such as elevated temperatures, affect the survival and performance of these introduced and native snails to determine whether the trend of introduced species outperforming native congeners persists under these conditions. In a series of laboratory experiments, I evaluated the influence of temperature on survival, grazing, growth, and attachment strength. I used a combination of classic thermal tolerance experiments, evaluating the upper thermal limit of each species, and ecologically relevant experiments to expose snails to elevated temperatures across a variety of exposure periods that simulated gradual and acute climate conditions.
In my third chapter, I synthesized occurrence records of marine species in Boston Harbor, an urban marine system, to examine biodiversity patterns and trends over decades of environmental change. I combined 159 years of species records, documenting 451 unique taxa of marine coastal birds, fish, macroalgae, macroinvertebrates and mammals. I conducted a biodiversity analysis using Average Taxonomic Distinctness (AvTD), a biodiversity metric that is useful when sampling methods and effort differ or are unknown across datasets, to determine how biodiversity has changed over time. Using AvTD, I analyzed biodiversity changes in relation to environmental variables such as dissolved oxygen, sea surface temperature, and sea level rise.
Together this work aims to provide a more comprehensive understanding of the interactions between introduced and native herbivores on introduced and native food resources, the effects of how climate change stressors on survival and performance, and the broader implications for biodiversity trends in a dynamic marine ecosystem.Ruth D. Turner Fund
United States Geological Survey NRPP
Smith College CFCD
Smith College Biological Sciences Endowed Fund
University of Massachusetts Graduate SchoolDoctor of Philosophy (Ph.D.)2026-02-0
Carbon Prices and Inflation in a World of Shocks: Systematically significant prices and industrial policy targeting in Germany
No full textClimate change and geopolitical tensions render supply shocks more likely, which can trigger inflation (shockflation). Additionally, the EU’s reliance upon an emissions trading system as its chief climate mitigation policy can give rise to inflation (carbonflation). Through simulations using an input-output price model for Germany, we show that the same systemically significant sectors – those essential for human livelihoods, production and commerce – present points of vulnerability for shockflation and also carbonflation, if carbon markets are the only policy tool deployed to cut emissions. A total of up to 91.3 percent of potential carbonflation can be attributed to just six systemically significant sectors. Our findings remain robust under varying assumptions regarding substitution and passthrough effects. The challenge for policymakers is to design policies that combine transformation with stabilization. Enhancing resilience, dampening price volatility and designing green industrial policies for these key sectors can reduce the macroeconomic risks of both carbonflation and shockflation
Higher amounts of habitual physical activity changes the relationship between hot flashes and subclinical cardiovascular disease risk
No full textThe menopausal transition is associated with increased risk for cardiovascular disease (CVD). Hot flashes (HF), a cardinal symptom of menopause, have been associated with increased CVD risk, particularly in perimenopausal women. Flow-mediated dilation (FMD) is an indicator of endothelial function and a subclinical CVD risk factor. Lower FMD has been associated with more HF. As moderate to vigorous physical activity (MVPA) is recognized to reduce CVD risk, our goal was to determine whether higher levels of MVPA change the relationship between HF and FMD in perimenopausal women. Healthy perimenopausal women had HF measured objectively using sternal skin conductance for 24 h. MVPA was determined using 7 days of actigraphy. Endothelial function was measured via brachial artery FMD on the non-dominant arm. Pearson correlations and multiple regression analyses were used to evaluate relationships between variables. Simple slopes analysis was performed to understand how MVPA moderates the relationship between HF and FMD. Lower FMD tended to correlate with a higher objective HF rate, and this relationship was stronger for HF measured during waking hours. Controlling for age and BMI, HF and the interaction between HF and MVPA were significant predictors of FMD. Simple slope analysis showed a significant HF effect on FMD with lower (−1SD) MVPA, whereas there was no significant relationship between HF and FMD with higher (+1SD) MVPA. These results suggest that MVPA moderates the relationship between FMD and objective HFs in perimenopausal women
Protecting Bioorthogonal Transition Metal Catalysts for Imaging and Therapy
No full textBioorthogonal chemistry is primarily centered on synthetic chemical reactions that can be performed in conjunction with complex biological systems. The main objects of interest in this realm are transition metal catalysts (TMCs), which are highly suitable for bioorthogonal processes, efficiently catalyzing transformations that enzymatic processes cannot accomplish. TMC-mediated bioorthogonal catalysis allows the creation of on-demand, in situ “factories” for producing drugs and imaging tools, offering a promising alternative in therapeutic and diagnostic strategies. However, it comes with a set of drawbacks as well: the direct use of TMCs in living systems presents challenges, including biocompatibility issues, poor water solubility, and inherent toxicity.
In this dissertation, I have chosen certain biomaterials and utilized them to integrate TMCs into engineered nanomaterial frameworks to design bioorthogonal “nanozymes” which help in improving TMC solubility, extend stability in biological systems, and reduce cytotoxicity, providing an elegant solution to the above drawbacks. Serving as the interface between the catalyst and biological systems, the nanomaterial surface can be engineered to optimize these interactions and enhance cellular uptake, control biodistribution, and enable active targeting, making them suitable for various impactful biomedical applications in diagnostics and therapy.
My primary research contribution, in essence, has been to explore new biomaterials, such as polymers, lipids and polysaccharides with biodegradable properties, that fit into the broad aim of synthesizing bioorthogonal nanozymes with enhanced activity, while minimizing adverse side effects. This represents a critical first step in establishing a pipeline in real-world settings where we can leverage the full power of TMCs without facing the downsides.
In the first part of my dissertation, I establish a foothold on this bigger project by leveraging oil-in-water nanoemulsions to solubilize Palladium (Pd)-based hydrophobic catalysts stabilized by a cationic poly(oxanorborneneimide)-based polymer. The nanoemulsion is designed to stabilize Pd-catalysts using natural oils with degradable crosslinking units to reduce their toxicity. These nanozymes show efficient catalytic activity inside cancer cells and activate pro-dyes and prodrugs.
In order to further mitigate toxicity while still utilizing bioorthogonal aspects of these TMC-based nanozymes, I subsequently developed another nanozyme system, which I describe in the next part of my dissertation. This system utilizes an alternative gold nanoparticle (AuNP)-based catalyst. Even with no known side-effects, AuNPs can still lose catalytic activity within cellular environments due to high concentrations of serum proteins and thiols. In order to prevent this, I utilize the strategy of coating these AuNPs with different carefully selected lipids to form a lipid corona. A key contribution of this work is the engineering of the lipid corona, which I achieved by incorporating various lipids that offer stability to AuNPs and also modulate their catalytic activity inside cancer cells for successful pro-dye and prodrug activation.
Building on the utility of Pd-catalyst used in this initial work, I next identify lipid nanoparticles (LNPs) as a known biodegradable platform to encapsulate and stabilize Pd catalysts. In the third part of this dissertation, I engineer the charge, fluidity, hydration, and saturation levels in these LNP formulations to modulate the catalytic activity and identify the best formulation for pro-dye and prodrug activation inside cancer cells with the goal of translating these formulations for future in vivo applications.
The last part of my dissertation focuses on developing a spatiotemporal bioorthogonal catalytic system for antibacterial applications. In order to do this efficiently, I utilize iron(III)-crosslinked alginate hydrogels to incorporate Pd-based nanozymes integrating the visible-light response of alginate hydrogels with bioorthogonal properties of nanozymes. These gel-embedded nanozymes show selective visible light activation of pro-dyes and prodrugs compared to dark conditions. I apply this strategy for stimuli-responsive activation of an antibiotic prodrug of Linezolid to eradicate multi-drug-resistant MRSA bacterial biofilms.
In summary, this dissertation demonstrates in a systematic manner that the protection of transition-metal catalysts using biomaterial-based nanoscaffolds enhances their solubility and stability and therefore helps create catalytic bioorthogonal nanozymes. The use of biomaterials in these nanozymes is a crucial step towards curbing toxicity while mitigating side-effects. The surrounding outside environment in these nanozymes can be engineered to modulate spatial and temporal aspects of these nanozymes for various biomedical applications.
Overall, my dissertation and broad research in general aim to touch on several approaches that could contribute to the development of better next generation bioorthogonal nanozymes with diverse potential applications in anticancer and antibacterial therapies.Doctor of Philosophy (Ph.D.)2026-02-0
TROPICAL CYCLONES AND SEDIMENT DYNAMICS IN MOUNTAINOUS ISLANDS: EROSION, TRANSPORT, AND COASTAL DELIVERY IN PUERTO RICO
No full textSmall, tropical and sub-tropical mountainous islands exposed to episodic tropical cyclones export a disproportionate sediment mass to the world’s coasts. Yet, the multiple mechanisms of sediment erosion via landslides in mountainous landscapes, fluvial transport, and export to the coast that occur during tropical cyclones are difficult to measure, thus limiting our understanding of the role of tropical cyclones in watershed-scale sediment dynamics and their importance in coastal sediment delivery. Sediment supply to coastal landforms in tropical coasts serve as building blocks to sustain beaches and mangrove forests wetlands. These landscapes provide high ecologic and economic value, and often serve as natural infrastructure and barriers to protect human activities along the coast. Despite their value, these ecosystems are threatened by a combination of coastal erosion and sea level rise, hence making sediment supply potentially critical for these systems to adapt. However, we do not know how important episodic tropical cyclone sediment delivery to mangrove forests is. Here I aim to study the role of tropical cyclones in three components of the basin-scale sediment budget dynamics in tropical islands: (1) sediment erosion via landslides, (2) fluvial transport, and (3) sediment export captured in reservoirs stratigraphy. I use Hurricane María (2017) and Fiona (2022) in Puerto Rico (PR) as an example of extreme events. And finally, I aim to quantify the relative role of tropical cyclones in delivering sediments to riverine and tidal fringe mangrove forests and how important minerogenic sediments are in soil carbon stocks and sequestration potential.
In Chapter 2, I aim to characterize the sedimentary and stratigraphic signature of María (2017) and Fiona (2022) relative to background sediments and compare how well internal stratigraphic structures reflect temporal patters in extreme flooding and sediment delivery associated with tropical cyclones. Here I collected repeated sediment cores at Caonillas reservoir to measure down-core geochemical and physical sediment properties: X-ray fluorescence (XRF), grain size, and loss-on-ignition (LOI). I found that María in 2017 generated three deposits characterized by relatively inorganic, medium-sized sand that is enriched in Sr and Ca elements relative to background mud. Additional cores collected after Fiona in 2022 revealed an additional event deposit attributed to the event, enriched in Be-7, which suggests recent deposition. Event deposits are linked to multiple flash floods generated during Maria and linked to individual rain bands evident in radar imagery collected during the event. Several rainbands of intense precipitation created the ideal conditions to erode sediments via landslide triggering and generate high transport capacity in the fluvial network to export sediments from upland watershed.
In Chapter 3, I aim to quantify the sediment budget from landslide erosion and fluvial transport during extreme events like María, and contextualize the role of tropical cyclones in sediment yields in the Caonillas reservoir, using María as an example of an extreme geomorphic event. Here I used repeated bathymetric surveys from 1990, 1995, 2000, 2012, and 2020 to assess sediment accumulation after María and contrast it with background rates of sediment accumulation. I found that 69% (± 2.9%) of the sediment deposited between 1995-2020 were related to four tropical cyclones, where María represents 23% (3.0 ± 0.1 x 106 Mg) of the total sediment accumulation. To assess sediment delivery, I built two rating curves for the period of 1995-2022 from an upstream hydrograph to assess suspended sediment delivery during María, Fiona, and three other earlier tropical cyclones. I found that 72.5% (± 3.3%) of the suspended sediment delivery were related to these tropical cyclones between 1995-2022, where María delivered 25% (5.3 ± 0.2 x 106 Mg) of the total suspended sediment transported over the entire study period. Sediment deposition and suspended sediment delivery estimates correspond to the equivalent of 20-22 and 23-24 years of long-term, background sediment yields, respectively. In addition, sediment erosion from landslides was calculated using lidar-derived DEMs collected before María in 2015, and after the event in 2018. I found that María mobilized 1.2 ± 0.2 x 106 Mg of sediments via landslides, which represent 8-11 years worth of annual sediment yields and 40% of the total María deposits, assuming all eroded sediment gets exported. Although this 1995-2022 period was particularly active in tropical cyclone impacts relative to the 20th century, our observations show that tropical cyclone-related sediment erosion and transport are the main drivers of sediment mobilization and transport in the 1995-2022 period, more than doubling long-term sediment delivery before 1990.
In Chapter 4, I aimed to determine the relative importance of minerogenic sediment supply on soil organic carbon stocks and sequestration rates in semi-arid mangrove systems. I sampled three mangrove forests whose soils represent different levels of sediment supply. Tidal fringe mangrove forests of Los Machos and Jobos Bay represent sites with minimal minerogenic sediment supply evident by their high organogenic, peaty substrate soils, while Rio Yauco Delta represents high sediment supply with minerogenic substrate and low organic-rich peat development. Despite these differences, carbon stocks for both tidal fringe and riverine mangrove soils contained similar soil organic carbon stocks with median values of 362 Mg C ha-1 and 352 Mg C ha-1, respectively. Organogenic mangrove sites in tidal fringe geomorphic setting showed lower accretion rates (1.04 mm yr-1 for MAC and 0.78 mm yr-1 for JOB) than the riverine site (4.5 mm yr-1 for RYD). Tidal fringe mangroves have also been historically prone to extensive die-off events with up to 45% in mangrove cover reduction These fringe systems are also more constrained in space than riverine mangroves, which showed mangrove expansion prior to a reductions in sediment supply likely caused by upstream damming in 1952. Our findings further inform soil carbon stocks accounting in underrepresented semi-arid mangroves environments and documents diverse anthropogenic impacts and their effects on carbon sequestration services by these systems.
The findings presented in this dissertation improves our understanding of upland sediment mobilization, transport, and export during large tropical cyclones in sub-tropical mountainous islands as well as their relative role in providing valuable sediments to coastal mangrove forests ecosystems. I found that intense rainfall derived from tropical cyclones, when occurring frequently enough, can be main drivers of sediment export in steep, landslide-prone basins. Landslides are a significant source (40%) of sediments in Caonillas sediment budget during hurricane María (2017), yet other geomorphic sources (e.g. gullies and channels) are important as well. Although outside of the scope of this study, it is acknowledge that gully and channel erosion are two additional sources that have yet to be constrained. Event derived sediment yields from steep upland basins can be 23-25 years of annual background sediment export, yet no significant event sediment deposition from María is observed in the two organogenic, tidal fringe mangrove forests sites. Contrastingly, small mangrove expansion was observed at the river mouth in the minerogenic substrate, riverine mangrove forests. Despite smaller area cover and reduced sediment supply due to upstream dam construction in 1952, high minerogenic sediment accretion rates at this riverine site makes it more effective in sequestering soil organic carbon as sea level increases. This illustrates the trade-offs between securing water and clean hydroelectric energy sources via dams and reservoirs, while the reduced sediment supply to the coast diminishes the carbon sequestration potential of downstream mangrove forests.The work presented in this dissertation was supported by NSF NRT ELEVATE (Elevating Equity Values in the Transition of the Energy System) (Award Number: 2021693), UMass Spaulding Smith Fellowship, Leo M. Hall Memorial Fund, Gloria Radke Memorial Fund, and NSF/GSA Graduate Research Fellowship, and John A. Black award.Doctor of Philosophy (Ph.D.)2026-02-0
COULOMB INTERACTION IN EMERGENT BCS SUPERCONDUCTIVITY
No full textUnderstanding the interplay between long-range Coulomb interactions and superconductivity is a challenging problem in condensed matter physics. While conventional theories successfully explain many superconductors, a controllable description of Coulomb interaction from first-principles remains absent, limiting theoretical predictions for ultralow temperature superconductivity. We address this challenge by developing a new approach based on precursory Cooper flow—a universal ansatz describing logarithmic temperature evolution of the normal state’s response to pair-creating perturbation. This method enables detection of Cooper instability and determination of critical temperatures from high-temperature measurements, extending theoretical predictions to unprecedented ultralow temperatures. Applying this framework to the uniform electron gas, we investigate Coulomb effects in two scenarios. In the high-density limit without phonons, we reveal exotic superconducting states in two- and three-dimensional systems, achieving theoretical predictions of Tc down to 10−100 TF . In three dimensions, we compare the Kohn-Luttinger and dynamical screening mechanisms under the Kukkonen-Overhauser ansatz, demonstrating that dynamical screening dominates over the traditionally assumed Kohn-Luttinger mechanism in the high-density limit. For systems with phonons, we develop an effective field theoretical treatment of the Tolmachev-Morel-Anderson pseudopotential, specifically addressing regimes where lattice vibrations are much slower than electron plasma modes. Using first-principles diagrammatic Monte Carlo calculations, we compute effective potentials in three-dimensional electron gas at metallic densities, providing a comprehensive microscopic understanding of the pseudopotential. Additionally, we examine the effects of Coulomb vertex corrections on electron-phonon coupling within the framework of effective field theory and explore the connection between our approach and density functional perturbation theory. These advances establish a foundation for studying ultralow temperature superconductivity where Coulomb interactions play a decisive role, opening new pathways for predicting superconducting properties in quantum materials where conventional approaches fail.My work was supported by the Simons Collaboration on the Many Electron Problem, and the National Science Foundation, the MURI Program “Advanced quantum materials—a new frontier for ultracold atoms” from AFOSR.Doctor of Philosophy (Ph.D.
Feasts Combined With Interferometry. Iii. The Low Column Density H <sc>i</sc> Around M51 And Possibility Of Turbulent-mixing Gas Accretion
No full textWith a new joint-deconvolution pipeline, we combine the single-dish and interferometric atomic hydrogen (H i) data of M51 observed by the Five-hundred-meter Aperture Spherical radio Telescope (FAST) (FEASTS program) and the Very Large Array (VLA) (THINGS). The product data cube has a typical line width of 13 km s-1 and a 2 sigma line-of-sight (LOS) sensitivity of H i column density NH i similar to 3.2 x 18 cm-2 at a spatial resolution of similar to 18 '' (similar to 0.7 kpc). Among the H i detected LOSs extending to similar to 50 kpc, similar to 89% consist of diffuse H i only, which is missed by previous VLA observations. The distribution of dense H i is reproduced by previous hydrodynamical simulations of this system, but the diffuse component is not, likely due to unresolved physics related to the interaction between the circumgalactic and interstellar media. With simple models, we find that these low NH i structures could survive the background ultraviolet photoionization, but are susceptible to the thermal evaporation. We find a positive correlation between LOS velocity dispersion (sigma v) and NH i with a logarithmic index of similar to 0.5. Based on existing turbulent mixing layer (TML) theories and simulations, we propose a scenario of hot gas cooling and accreting onto the disk through a TML, which could reproduce the observed power index of similar to 0.5. We estimate the related cooling and accretion rates to be roughly one-third to two-thirds of the star formation rate. A typical column density of diffuse H i (similar to 1019 cm-2) can be accreted within 300 Myr, the interaction timescale previously estimated for the system. Such a gas accretion channel has been overlooked before, and may be important for gas-rich interacting systems and for high-redshift galaxy evolution