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Formation of Sandwich Complexes between Lanthanides and Chlorophylls Recovers Photosynthetic Activity and Imparts Crop Resistance to UV Stress via Single-Nanodose Seed Treatment
No full textLanthanides (Lns) have been used as fertilizers in several countries over the past 50 years, yet their interaction with plant metabolism remains largely unknown, with only a few confirmed biological roles, such as cofactors in specific dehydrogenases found in methylotrophic organisms. This study investigates the interplay between Ln ions and chlorophylls (Chls), showing that throughout the Ln series, Ln-Chls replace Mg2+ at the center of the pigment structures through the formation of sandwich-like Ln-porphyrin complexes. When applied as seed treatment to four staple crops (i.e., barley, chickpea, corn, and soybean), Lns enhance seedlings’ growth. Mobility of lanthanum from the rhizosphere to plants is favored when the metal is in neutral or weakly charged forms, as studied by changing the salt used (i.e., LaCl3, La(NO3)3, LaPO4, La2(CO3)3, [LaEDTA(H2O)3]K, or [LaDOTA(H2O)]K). These results highlight the role of the Casparian strip in modulating the apoplastic movement of Lns in the stele and suggest that plants possess an uptake system with binding strengths comparable to or stronger than La-DOTA complexes. Additionally, when complexed with trehalose in seed treatments, Ln3+ protected pigments from UV stress, enhancing the resilience of the four staple crops to abiotic stressors.MIT Climate Grand Challenge, Office of Naval Research (N000141912317
Globalizing “Humanism”: A Comparative Framework for Understanding Ethical and Literary Revivals Across Eurasia
No full textHumanism is often framed through the lens of Renaissance Europe, where classical revival and secular individualism defined a powerful cultural ideal. Yet similar movements—grounded in ethical self-cultivation, textual engagement, and educational reform—have emerged independently across diverse historical contexts. This study offers a comparative framework for understanding four such revivals: Confucian classicism in Tang and Song China, Byzantine paideia under the Palaiologos dynasty, Renaissance Italy’s metaphysical humanism, and the Arabic Nahda’s reformist thought in the colonial age. Each reflects a distinctive negotiation between inherited tradition, moral agency, and sociopolitical upheaval. Five core features recur across these cases: a belief in human ethical potential, reverence for classical texts, dialogue with religious orthodoxy, institutional mediation, and the emergence of a learned elite committed to public responsibility. Beginning with China and moving westward, the analysis disrupts conventional genealogies and recasts humanism as a plural, adaptive phenomenon. Figures such as Han Yu, Liu Zongyuan, Theodore Metochites, Giovanni Pico della Mirandola, and Rifa’a al- Tahtawi exemplify the variety of humanistic expression, each articulating a vision of ethical renewal suited to their cultural moment. Rather than advancing a fixed definition, the project treats humanism as a historically contingent mode of reflection on what it means to be human—one that emerges in response to crises of meaning, legitimacy, and identity. Across Eurasia, literary and intellectual revivals have served as means for societies to reimagine moral authority, reassert cultural identity, and envision more just forms of life. Reconsidering humanism in this way not only recovers overlooked traditions but enriches the vocabulary available for confronting contemporary challenges.S.B
Report to the President for year ending June 30, 2025, Office of the Vice Provost for Faculty
No full textThis report contains the following sections: Overview, Staffing Changes, Completion of OVPF Strategic Plan, Faculty Advancement, Faculty Recruitment and Retention, and Institute-wide Faculty Community and Culture
When Girls Just Wanna Have Fun, How Do They Go? A Mixed Methods Study of Nighttime Leisure Travel in Boston
No full textWhen we think of urban living and its depictions in popular culture, many shows and movies depict characters in leisure activities, such as meeting friends, going on dates or pursuing hobbies, often at night. Despite the prominence of the night as a key theme in depictions of urban leisure, transportation planners have rarely focused on nighttime leisure travel as an area of intensive study beyond the lens of safety. This thesis investigates the nighttime leisure travel patterns of residents and students in Greater Boston through statistical analysis and data sculpture with a focus on how these vary by gender. To create a baseline understanding of travel patterns, I focused on the Boston Metropolitan Area and used the most recent version of the Massachusetts Department of Transportation’s Household Travel Survey from 2011. I limited my analysis to a fixed set of leisure activities during a fixed nighttime period to understand associated travel behaviors. I also implemented a data sculpture method to investigate how a subset of MIT students made decisions around their travel modes. I found that women travelled differently from men, in that they spent more time walking and were more likely to be passengers in a car. In contrast, men were more likely to be behind the wheel and travel further. Both men and women showed a preference for walking over all other modes when leaving an activity. Together, these findings indicate that nighttime leisure travel is not a simple extension of daytime patterns. To better design nighttime transportation that accommodates gender differences, planners need to respond to the special qualities of the city after dark.M.C.P
Modulating Nanoparticle Size to Understand Factors Affecting Hemostatic Efficacy and Maximize Survival in a Lethal Inferior Vena Cava Injury Model
No full textIntravenous nanoparticle hemostats offer a potentially attractive approach to promote hemostasis, in particular for inaccessible wounds such as noncompressible torso hemorrhage (NCTH). In this work, particle size was tuned over a range of <100-500 nm, and its effect on nanoparticle-platelet interactions was systematically assessed using in vitro and in vivo experiments. Smaller particles bound a larger percentage of platelets per mass of particle delivered, while larger particles resulted in higher particle accumulation on a surface of platelets and collagen. Intermediate particles led to the greatest platelet content in platelet-nanoparticle aggregates, indicating that they may be able to recruit more platelets to the wound. In biodistribution studies, smaller and intermediate nanoparticles exhibited longer circulation lifetimes, while larger nanoparticles resulted in higher pulmonary accumulation. The particles were then challenged in a 2 h lethal inferior vena cava (IVC) puncture model, where intermediate nanoparticles significantly increased both survival and injury-specific targeting relative to saline and unfunctionalized particle controls. An increase in survival in the second hour was likewise observed in the smaller nanoparticles relative to saline controls, though no significant increase in survival was observed in the larger nanoparticle size. In conjunction with prior in vitro and in vivo experiments, these results suggest that platelet content in aggregates and extended nanoparticle circulation lifetimes are instrumental to enhancing hemostasis. Ultimately, this study elucidates the role of particle size in platelet-particle interactions, which can be a useful tool for engineering the performance of particulate hemostats and improving the design of these materials
Essays on Environmental Regulation
No full textI focus on three challenges that often confront regulators in designing environmental regulations around the world: equity-efficiency tradeoffs, incomplete information, and significant ecologic and economic uncertainty across time and space. First, I analyze the efficiency and distributional consequences of trade restrictions in environmental permit markets, I study common trade restrictions—segmentation and production requirements—in Iceland’s fisheries permit market, showing how they increase employment and compress the income distribution at an efficiency cost. Second, in the U.S. Conservation Reserve Program, Anna Russo and I find that auction mechanisms designed to incentivize land conservation suffer from widespread non-additionality due to adverse selection in land use. A redesigned scoring system that accounts for counterfactual land outcomes improves welfare. Third, using a stylized model calibrated to the Atlantic scallop fishery, Aaron Berman and I evaluate the use of output, input, and quantity-based regulations over time when a resource exhibits ecological and economic uncertainty across large areas of space. We show that, for a given ultimate sustainability goal, output taxes maximize value but exacerbate inequality and ecological risk, while input limits can strike a balance between flexibility, equity, and robustness.
JEL Classification: L51, Q22, Q28Ph.D
Multi-objective Optimization of the Process Design in HSLA Steels Using Physically Based Mean Field Modeling
No full textA multi-objective optimization approach is presented for the process design of an X70 HSLA steel plate using a physically based mean field (PBMF) model. The PBFM model incorporates an integrated precipitation and recrystallization model to describe the microstructural evolution due to the interaction of strain-induced precipitation of niobium and titanium carbonitrides and static recrystallization of austenite. An integer multi-objective optimization problem is formulated, and the non-dominated sorting genetic algorithm (NSGA-II) is applied on the PBMF model to determine a list of optimal processing routes that satisfy specific process design constraints. Aiming in increasing the strengthening and fracture toughness of the material, a trade-off between the microstructural objectives is considered; average ferrite grain size after accelerated cooling, niobium content in solution and residual strain at the end of multipass hot rolling. Higher residual strains and lower niobium in solution due to higher degree of strain-induced precipitation result in smaller average ferrite grain sizes. An optimal processing route was selected, and the microstructure and precipitation state of the processed material were characterized experimentally revealing a good agreement with model predictions. The proposed approach can contribute to the process design of HSLA and microalloyed steels
Report to the President year ended June 30, 2025, Chancellor for Academic Advancement
No full textThis report contains the following section: Activities within the Chancellor for Academic Advancement’s Offic
High-level specification and efficient implementation of pipelined circuits
No full text© 2001 IEEE. This paper describes a novel approach to high-level synthesis of complex pipelined circuits, including pipelined circuits with feedback. This approach combines a high-level, modular specification language with an efficient implementation. In our system, the designer specifies the circuit as a set of independent modules connected by conceptually unbounded queues. Our synthesis algorithm automatically transforms this modular, asynchronous specification into a tightly coupled, fully synchronous implementation in synthesizable Verilog
Automated and Blind Detection of Low Probability of Intercept RF Anomaly Signals
No full textACM MobiCom ’24, November 18–22, 2024, Washington D.C., DC, USAAutomated spectrum monitoring necessitates the accurate detection of low probability of intercept (LPI) radio frequency (RF) anomaly signals to identify unwanted interference in wireless networks. However, detecting these unforeseen low-power RF signals is fundamentally challenging due to the scarcity of labeled RF anomaly data. In this paper, we introduce WANDA (Wireless ANomaly Detection Algorithm), an automated framework designed to detect LPI RF anomaly signals in low signal-to-interference ratio (SIR) environments without relying on labeled data. WANDA operates through a two-step process: (i) Information extraction, where a convolutional neural network (CNN) utilizing soft Hirschfeld-Gebelein-Rényi correlation (HGR) as the loss function extracts informative features from RF spectrograms; and (ii) Anomaly detection, where the extracted features are applied to a one-class support vector machine (SVM) classifier to infer RF anomalies. To validate the effectiveness of WANDA, we present a case study focused on detecting unknown Bluetooth signals within the WiFi spectrum using a practical dataset. Experimental results demonstrate that WANDA outperforms other methods in detecting anomaly signals across a range of SIR values (-10 dB to 20 dB)