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Local Angiotensin Converting Enzyme 2 (ACE2) Enzymatic Activity Modulates Cholinergic Interneuron Function in the Dorsolateral Striatum
No full textThe renin angiotensin system (RAS) is an ancestrally ancient peptidergic signaling pathway best known for its role regulating blood pressure in the periphery. However, its presence and importance in the central nervous system has more recently been identified and is less well understood. Previous work shows RAS is expressed in the nigrostriatal pathway of the basal ganglia and has been implicated in basal ganglia disorders including Parkinson’s disease (PD) and levodopa-induced dyskinesia (LID). Interestingly, the canonical and noncanonical arms of the RAS pathway produce opposite effects on PD disease vulnerability and progression. The shift from the neurodegenerative canonical RAS to the neuroprotective noncanonical RAS is regulated by the enzymatic activity of angiotensin converting enzyme 2 (ACE2). To explore how RAS modulates basal ganglia function under physiological conditions, we assessed the expression of both canonical and noncanonical RAS in the dorsolateral striatum (DLS), a key integration hub for the basal ganglia, and found that ACE2 is broadly expressed in the region. Interestingly, cholinergic interneurons (CINs), an interneuron population essential for striatal function, showed unique enrichment of angiotensin II type 1 receptor (AT1R) and mas receptor (MasR), the receptor counterparts to the substrate and product of ACE2 activity. Reducing ACE2 enzymatic activity in the DLS, either through conditional ablation or pharmacological inhibition, altered how CINs respond to DA input during burst events, including a significant reduction in the amplitude of CIN pausing following DA burst release events. This pause is known to be modulated in part by dopamine D2 receptor activity, and AT1R and D2R have been shown to form heteromers capable of bidirectional inhibition in the striatum. AT1R inhibition and D2R agonism through coinjection of MLN4760 and quinpirole, respectively, reduced CIN activity in an additive manner as compared to each treatment alone and a proximity ligation assay on DLS sections revealed that AT1R and D2R colocalize within 40nm of each other on CINs. Functionally, unilateral ACE2 ablation in the DLS produced an ipsilateral turn bias without altering overall locomotion, consistent with altered striatal asymmetry. Bilateral ablation impaired motor learning in a rotarod paradigm, linking RAS-dependent CIN modulation to adaptive motor control. Taken together, these findings suggest that ACE2 regulates CIN sensitivity to dopaminergic input by maintaining the balance between AT1R- and MasR-mediated signaling. AT1R inhibits D2R-dependent CIN pauses, while ACE2 activity promotes MasR activation, which relieves this inhibition. Disruption of this balance such as in PD or COVID may therefore contribute to basal ganglia dysfunction through impaired dopaminergic–cholinergic integration. This work identifies a novel mechanism by which the brain RAS modulates striatal microcircuit function, bridging molecular signaling and motor learning
Implementation of the Framework for Great Schools: Lessons from New York City
No full textThis dissertation explores the implementation of the Framework for Great Schools in the New York City Department of Education from 2015 through 2019. The study addresses a gap in the literature, specifically regarding NYC School Survey data and the relationship between it, school context, and student outcomes, at a time when families and district leaders regularly use publicly available school-level data to inform their decision-making, understanding how frameworks such as the Framework for Great Schools is essential. The Framework focuses on six elements: Rigorous Instruction, Supportive Environment, Collaborative Teachers, Effective School Leadership, Strong Family and Community Ties, and Trust. It has been central to the New York City Department of Education’s vision for improving schools.
This study focused on three research questions, which addressed (1) how the elements and measures influenced each other in varying school contexts, (2) how the elements and measures related to student outcomes, and (3) how changes in measures influenced changes in outcomes. To address these questions, this dissertation employed Exploratory Data Analysis to uncover patterns, relationships, and anomalies. The study used a variety of relatively simple statistical techniques to probe survey results, school context variables, and student outcomes at the school level.
The analysis shows that, although the system as a whole did not exhibit significant improvement at the district level across five of the six elements, there was considerable change at the school level. The elements of Supportive Environment and Rigorous Instruction were most closely linked to student outcomes, but there was no significant correlation between annual changes and improvements in student performance. Notably, schools serving a high percentage of English Language Learners and schools with high levels of economic need showed improvement. In contrast, schools with a high percentage of students with IEPs did not experience similar gains. Furthermore, the study emphasizes the significant influence of student socio-economic status on outcomes and demonstrates that strong performance in the Framework scores was insufficient to outweigh disparities in student achievement
A Study of the Impacts of Infusing Data Analysis and Research in an Interdisciplinary Environmental Economics Course
No full textThis paper explores the impacts of introducing quantitative literacy skills in an interdisciplinary Environmental Economics course typically taught as an issues and policy course without a quantitative component. The study examines the effects of infusing an engaging, student-selected data collection and analysis assignment on students\u27 quantitative reasoning skills, as well as their interest in and attitudes about data analysis and quantitative information. Using data gathered from a set of pre- and post-assessment questions designed to measure changes in quantitative reasoning skills and attitudes, the findings point to significant attitudinal impacts, gains, but smaller, insignificant gains in quantitative reasoning skills
Mind the Gap: Morphological Defectivity and Suffixal Competition in Polish
No full textThis study investigates morphological defectivity and suffixal competition in the genitive singular of Polish masculine inanimate nouns. Drawing on survey-based grammaticality judgments from native speakers, it examines how respondents select between the suffixes -a and -u or reject both as unacceptable, thereby signaling defectivity. Mixed-effects logistic regressions revealed that defectivity was rare overall but patterned systematically by age, education, and region, with additional baseline variability across lexical items. Suffix choice showed a strong preference for -a, modulated by age, education, and region, with additional baseline variability across lexical items. These findings inform our understanding of paradigm structure, sociolinguistic variation, and the interface between morphology, semantics, and lexical processing
Mechanistic Studies of Aerobic Photochemistry: Gold Nanoclusters, Nanoparticles, and Solution-Phase Systems
No full textThis thesis comprises five chapters as enumerated below.
Chapter 1 describes our findings on the reactions of Au glutathione nanocluster (Au20SG16) with singlet oxygen (1O2) in D2O. We noticed it underwent a self-photooxidation reaction. Leading us to mechanistic studies using photophysical, photochemical, theoretical, and indirect trapping methods. We found rapid total quenching of singlet oxygen (1O2) by ground-state Au20(SG)16, with evidence for dioxygen insertion into the nanocluster. Supported by analyses with IR, ESI-MS, and density functional theory, we propose the formation of Au–O–O–SG bonds in the Au nanocluster. The expansion of the staple motif from dioxygen insertion is attributed to heightened lability and blebbing by the O–O group. We then demonstrated that the self-photooxidized Au20(SG)16 undergoes oxygen-atom transfer to a phosphine trap in the dark.
Chapter 2 discusses the air-borne singlet oxygen photooxidation of prenyl phenol coated silica nanoparticles. We uncovered significant selectivity for dihydrofuran formation over allylic hydroperoxide formation. The hydrophobic particle causes prenyl phenol to produce an iso-hydroperoxide intermediate with an internally protonated oxygen atom, which leads to dihydrofuran formation as well as O-atom transfer. In contrast, hydrophilic particles cause prenyl phenol to produce allylic hydroperoxide, due to phenol OH hydrogen bonding with SiOH surface groups. Mechanistic insight is provided by air/nanoparticle interface coated with the prenyl phenol, in which product yield were 6-fold greater on the hydrophobic nanoparticles compared to the hydrophilic nanoparticles and total rate constants (ASI-kT) of 1O2 were 13-fold greater on the hydrophobic vs hydrophilic nanoparticles. A slope intersection method (SIM) method was also developed that uses the airborne 1O2 lifetime (τairborne) and surface-associated 1O2 lifetime (τsurf) to quantitate 1O2 transitioning from volatile to non-volatile and surface boundary (surface···1O2). Further mechanistic insight on the selectivity of the reaction of prenyl phenol with 1O2 was provided by DFT calculations.
Chapter 3 describes our study of the mechanism of association of airborne 1O2 at the air/surface interface by using 1O2’s near infrared (NIR) phosphorescence and geometric analysis based on slope inflection angle (θ) of air-to-particle transfer. This offered insight to 1O2-surface binding as opposed to conventional kinetic analysis. Two 9,10-disubstituted anthracene quenchers were adsorbed to the particle surface, producing θ ranging from ~91° (greater quenching) to ~99° (less quenching) due to the reduction of airborne 1O2 lifetime (τairborne) by 43% to 95%. A more efficient (lower θ) 1O2 quenching is observed in the order dimethylanthracene-coated particle \u3e anthracene dianion-coated particle \u3e native silica. The anthracene dianion charges and surface silanols did not enhance the 1O2 surface quenching. Indeed, the quenching of airborne 1O2 by native silica was minimal, in which a slight reduction in its surface lifetime (τsurf) was observed (0-5%). This θ approach opens up opportunities in fields such as surface oxidation processes in nanoplastics that is an emerging concern.
Chapter 4 describes a strategy that enables the numerical quantification of the 1O2 molecules that are required to oxidize a particle as a proxy for the number of 1O2 molecules that are lethal to a cell. Few studies have focused on how to estimate the number of 1O2 molecules required to kill a cell. This estimate is needed since 1O2 is thought to account for 75% of the photodynamic effect instead of oxygen radicals and ions. The particle system discussed in this chapter is ~9-fold larger than the diameter of the radiation-induced fibrosis (RIF) tumor cell, but the number of 1O2 reactive sites are nearly identical, each ~1.4 × 1011 per particle and per cell. Interestingly, the combined 1O2 reactive amino acids, unsaturated lipid, and guanine sites is 50- to 180-fold less than the 1.2 × 109 1O2 molecules needed to kill each cell in vivo, where [1O2]ss » 1 mM. Here, we advance an understanding of mechanistic details of 1O2 reactions at both solid particle and cell surfaces. We find that comparison is better suited on a per particle and per cell basis because the particle volume is 670-fold greater than the cell volume and particles are packed ~105 per cm3, whereas cells are 108 per cm3.
Chapter 5 highlights a paper by Huang et al. in an issue of Photochemistry and Photobiology in 2024. It describes shades of phototoxicity in fluorescent imaging agents that are not intended to be phototoxic. Phototoxicity was assessed using a modified neutral red uptake (NRU) in vitro assay with mean photo-effects (MPE) for the fluorescent agents IRdye800, indocyanine green (ICG), proflavine, and methylene blue (MB), with comparisons to known phototoxic agents benzoporphyrin derivative (BPD) and rose bengal (RB). The experimental conditions were aimed to mimic clinical settings, using not only visible light, but also near infrared light for insight to photosafety and deep tissue damage. Molecular mechanisms underlying the phototoxicities were not sought, but IRdye800 and ICG were mainly deemed to be safe, whereas proflavine and MB would require precautions since phototoxicity can overshadow their utility as fluorescent imaging agents
Recognition at Work: How Managerial Acknowledgment Shapes Team-Level Outcomes
No full textEmployee recognition has become a central focus for organizations worldwide, with billions of dollars spent annually on recognition programs. Despite this investment, scientific research on the effectiveness of recognition beyond performance outcomes remains limited. Furthermore, little is known about how recognition operates at the team-level and the specific attributes that make recognition impactful. This study addresses these gaps by disentangling the nuanced attributes of recognition and exploring their influence on employee perceptions of recognition. It also examines how these perceptions affect key outcomes, including perceptions of manager support, job security, autonomy, team cohesion, and engagement, and tests whether trust moderates the relationship between objective recognition and perceived recognition. Using data from an organization’s recognition platform, the findings indicate that recognition quality was related to perceived recognition, however this relationship differed across samples. Trust did not moderate this relationship in either dataset. Perceived recognition was consistently associated with job security, manager support, autonomy, and cohesion, and each of these work conditions, as well as perceived recognition itself, predicted engagement. By integrating objective recognition data with employee perceptions, this study provides a novel methodological approach to understanding the collective impact of managerial recognition on teams and offers evidence-based insights for improving recognition practices and team-level outcomes
Towards Unbordered Worlds: Mutual Aid Amid Border Internalisation in New York City
No full textThis study explores the relationship between mutual aid and border regimes through the case of Tompkins Distro, a mutual aid group that organises a weekly food distribution in the East Village of New York City. It focuses specifically on two forms of border internalisation that have shaped the emergence and context of Tompkins Distro: welfare state bordering and interior border enforcement. Drawing on four months of participant observations, interviews with core organisers, and documentary analysis, the study examines how Tompkins Distro meets people’s needs each week through a framework of collective care that actively rejects border logics of deservingness and deterrence. Tompkins Distro’s work is further situated within the incipient community politics unfolding across the United States that are refusing the nation state’s authority to dictate who belongs, who can move, and who can stay. Mutual aid efforts like Tompkins Distro contribute to these politics in providing examples of alternative modes of belonging to place that are hyper-local, grounded in reciprocity, and ultimately disinterested in state produced membership to the imagined national community. I argue that this case illuminates the dual importance of mutual aid to the project of border abolition: not only mitigating the immediate violences of border regimes by organising life-sustaining direct aid, but also offering glimpses of other possible, unbordered worlds and how these are being practiced in the present
Maintenance Mode for Digital Dwellers
No full textIn an ever-expanding digital landscape that operates on the commodification of user-generated materials, whether through direct or “dark pattern” extraction, it becomes vital for educators to employ digital practices that normalize critical reflection about the creation and storage of digital content. These practices should create better understanding of the underlying infrastructure of content management and storage.
This capstone project, “Maintenance Mode for Digital Dwellers,” is an adaptable pedagogical guide that instructors can use to engage learners in strategies and systems for managing their personal digital materials. Participants are encouraged to engage with their digital maintenance and archival practices through a critical lens. The project’s core themes explore personal data as digital memory, digital agency, and what it means to maintain one’s “digital self.” The workshop pulls from established practices in the Personal Digital Archiving field and Digital Humanities while tailoring the material to educators who may want to introduce these concepts in packed curriculums or to users interested in introductory methods for digital maintenance
Designing a Research Study: Controlling for a Variable and Using ChatGPT
No full textThis assignment uses a hypothetical society to help students understand the idea of “controlling for a variable” and practice applying it to a real-world research question. Students design a research approach to examine whether income differences are better explained by family background or by systemic prejudice, working within clear data limits. ChatGPT is used as a research guide to help students brainstorm, test, and revise their methods, while encouraging them to critically evaluate the usefulness and limits of AI-generated suggestions. The assignment emphasizes careful reasoning, clear research design, and thoughtful use of AI as a support for learning rather than a substitute for analysis
Notes from the Editor
No full textI am very pleased to welcome you to the second issue of the 31st volume of Urban Library Journal, which is a collection of proceedings from the LACUNY Institute held on Wednesday, May 21, 2025 as a hybrid event at City College of New York. The theme of the Institute was “The Persistent Record: Preserving Knowledge in an Uncertain World.” It explored challenges faced by librarians and information professionals across our profession. Presentations delved into the preservation of politicized data, intellectual freedom, censorship, and how information professionals can navigate these challenges in an ever-changing world