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Codicology and the Transformation of Islamic Law: A First Assessment of the Tarjīḥāt al-bayyināt in the Princeton Garrett Collection
Get PDFIn Islamic law, preponderance (tarjīḥ)—a practical method for mujtahids to resolve legal contradictions (taʿāruḍ) between proofs—has been known in the uṣūl tradition from at least the 10th-century jurist al-Jaṣṣāṣ (d. 370/981). Yet, it is in several 17th and 18th-century Arabic and Ottoman manuscripts of Princeton’s Garrett Collection that we encounter summary-like lists labelled “tarjīḥāt al-bayyināt” (“TB s”), which succinctly compile the complex rules of preponderance. Organized into three-columned lists, on loose leaves, as annotations in the margin or separate textual units, the TB s follow a grammatical and visual layout that made them predictable and recognizable for manuscript readers. This paper examines the TB s as a codicological phenomenon, arguing that they served as a shorthand for legal practitioners familiar with evidentiary law and that their presence suggests a broader transformative process of readers’/legal practitioners’ relationship with codices of positive law at this critical moment in the history of Islamic law
Recording Justice in Byzantine and Early Islamic Egypt (550–800): Material Culture, Ordinary People, and the Making of the Islamic State
Get PDFMy dissertation offers the first social and legal history of the transition from Byzantine to Islamic Egypt (550–800), shifting our attention to actors in the Egyptian countryside—monks, bishops, and villagers—and the ways in which disputing, petitioning, and monastic disciplining influenced the texture of Islamic justice and institution-building. By integrating literary sources and material evidence from the underexplored archive of Arabic, Greek, and Coptic papyri, Recording Justice posits that Muslim state-building was never exclusively a matter of top-down imposition of political will and reforms by caliphs and governors. Instead, I argue that the social and legal expectations of the Egyptian populace—most of them Coptic Christians—were informed by centuries of Byzantine rule, and their expectations of scribal documentation, legal process, and authority actively shaped how, where, and when officials appointed by the Islamic state could dispense justice. Through the bottom-up use of papyri, Recording Justice resists the common periodization into pre-Islamic and Islamic, maintaining that a judicial crisis had been in the making in Egypt long before the Arab conquests in the 640s. The nature of this crisis was that the steady shift of power into the countryside enabled bishops, monks, and local administrators to accumulate substantial judicial and executive functions, resulting in access barriers to and the obsolescence of official courts as disputes were increasingly resolved through the more informal means of arbitration and mediation. Recording Justice reveals a new model of the Islamic state, which needed to negotiate with and garner acceptance from a rural populace that was predominantly non-Muslim and had specific ideas about how to be governed. The dissertation argues that shortly after the Arab Muslim conquests, state officials began issuing legal documents, specifically promissory notes (adhkār ḥaqq) and quittances (barāʾāt), recording the claims and entitlements of ordinary people in the Arabic language. By doing so, their legal claims became tied to the sovereignty of the fledgling Islamic state, guaranteed by a web of administrators, scribes, and witnesses, all of whom endowed these documents with their authoritative marks. By the late eighth century, the Islamic judiciary had ascended to the top tier in the administration of justice in Egypt, with political elites even deferring high-level political disputes to the judiciary. This development was undergirded by the judiciary’s growing reliance on a new type of legal document, the affidavit (iqrār), which operated under heightened standards of evidence and placed a premium on declarants’ legal accountability (taklīf). The affidavit not only became the hallmark of Islamic justice for centuries to come but also left a decisive mark on Coptic scribal culture. With that, Egypt transformed from an arbitration society into one in which official courts were once again accessible and where the presence of the Islamic judiciary as the top tier of justice functioned as an effective check on the powers of rural arbiters
ARNT-dependent HIF-2α signaling protects cardiac microvascular barrier integrity and heart function post-myocardial infarction
Get PDFMyocardial infarction (MI) compromises the cardiac microvascular endothelial barrier, increasing leakage and inflammation. HIF2α, predominantly expressed in cardiac endothelial cells during ischemia, has an unclear role in barrier function during MI. Here, we show that inducible, adult endothelial-specific deletion of Hif2α in mice leads to increased mortality, cardiac leakage, inflammation, reduced heart function, and adverse remodeling after MI. In parallel, human cardiac microvascular endothelial cells (HCMVECs) lacking HIF2α display impaired barrier integrity, reduced tight-junction proteins, increased cell death, and elevated IL-6 levels, effects that are alleviated by overexpressing ARNT, a key partner of HIF2α under hypoxic conditions. Interestingly, ARNT, but not HIF2α, directly binds the IL-6 promoter to suppress its expression. These findings suggest the HIF2α/ARNT axis as a protective mechanism in heart failure post-MI and identify potential therapeutic targets to support cardiac function
Functional Connectivity of Red Chlorophylls in Cyanobacterial Photosystem I Revealed by Fluence-Dependent Transient Absorption
Get PDFExternal stressors modulate the oligomerization state of photosystem I (PSI) in cyanobacteria. The number of red chlorophylls (Chls), pigments lower in energy than the P700 reaction center, depends on the oligomerization state of PSI. Here, we use ultrafast transient absorption spectroscopy to interrogate the effective connectivity of the red Chls in excitonic energy pathways in trimeric PSI in native thylakoid membranes of the model cyanobacterium Synechocystis sp. PCC 6803, including emergent dynamics, as red Chls increase in number and proximity. Fluence-dependent dynamics indicate singlet–singlet annihilation within energetically connected red Chl sites in the PSI antenna but not within bulk Chl sites on the picosecond time scale. These data support picosecond energy transfer between energetically connected red Chl sites as the physical basis of singlet–singlet annihilation. The time scale of this energy transfer is faster than predicted by Förster resonance energy transfer calculations, raising questions about the physical mechanism of the process. Our results indicate distinct strategies to steer excitations through the PSI antenna; the red Chls present a shallow reservoir that direct excitations away from P700, extending the time to trapping by the reaction center
Unconventional gate-induced superconductivity in transition-metal dichalcogenides
Get PDFSuperconductivity in few-layer semiconducting transition-metal dichalcogenides (TMDs) can be induced by field-effect doping through ionic-liquid gating. While several experimental observations have been collected over the years, a fully consistent theoretical picture is still missing. Here we develop a realistic framework that combines the predictive power of first-principles simulations with the versatility and insight of Bardeen-Cooper-Schrieffer gap equations to rationalize such experiments. The multivalley nature of semiconducting TMDs is taken into account, together with the doping- and momentum-dependent electron-phonon and Coulomb interactions. Consistently with experiments, we find that superconductivity occurs when the electron density is large enough that the valleys get occupied, as a result of a large enhancement of electron-phonon interactions. Despite being phonon driven, the superconducting state is predicted to be sensitive to Coulomb interactions, which can lead to the appearance of a relative sign difference between valleys and thus to a +− character. We discuss qualitatively how such scenario may account for many of the observed physical phenomena for which no microscopic explanation has been found so far, including in particular the presence of a large subgap density of states, and the sample-dependent dome-shaped dependence of on accumulated electron density. Our results provide a comprehensive analysis of gate-induced superconductivity in semiconducting TMDs, and introduce an approach that will likely be valuable for other multivalley electronic systems, in which superconductivity occurs at relatively low electron density
Instability in the environment and children’s in-school self-regulatory behaviors
Get PDFIntroduction: Experiences of chronic and/or extreme stress early in childhood are associated with altered self-regulatory behaviors. However, there is a range of variability in children’s behavioral outcomes after experiences of stress. Understanding what contributes to this variability in children’s responses to stress can aid in the development of more effective programs aimed at supporting children’s self-regulatory processes. The current study examined relationships between indices of environmental stability and changes in children’s self-regulatory behaviors. Methods: Ratings of children’s self-regulatory behavior were collected in collaboration with a school program once a month over the course of the academic year. Measures of environmental stability were collected for each child. Results: Children demonstrated increases in self-regulatory behaviors over the course of the study. Additionally, children in home environments characterized by high levels of environmental instability demonstrated greater positive behavior change during the program. Discussion: This study suggests that there are important individual differences in children’s patterns of self-regulatory behavior changes, and points to complex interactions between children’s home environment, implementation of a more positive and stable environment, and changes in behavior.</p
Seed Media: Emergent Forms for the Environmental Humanities
Get PDFAt the intersection of media studies and the environmental humanities, “Seed Media” articulates a theory of seeds as texts, mobilizes this framework to assess seeds in both real-world and fictional contexts, and showcases the urgent relevance of humanistic research in the ongoing climate crisis. Especially since the global implementation of American agronomic agendas in the latter half of the 20th century, the agroindustrial complex has prioritized the biological and genetic commodification of seeds over the complex and culturally rich relationships between human, food, and land. Seeds constitute cultural and historical artifacts—stories and lifeworlds in their own right—as evinced in the perspectives and beliefs of Indigenous and non-Western traditions and cosmologies, sustainable farmers and horticulturalists, and land-defenders and activists. This dissertation makes the case for a humanistic approach that harnesses the tools of literary criticism and media theory to consider seeds as media. The first two chapters deploy humanistic theories of archive to position seeds in their historical, cultural, and political contexts. Current archival practices preserve the past to the detriment of the future, as exemplified in the world’s largest seed bank, the Svalbard Global Seed Vault. Rather than stockpiling seeds in archives, understanding them as archives resists this paradox and animates seeds’ mediative capacities and dynamic chronologies: the recovered seeds of Emily Dickinson both complement and invoke the canonical poet’s oeuvre. Attending to seeds in literary and media contexts supplements incomplete seed archives in a time of climate crisis. The last three chapters take up a constellation of case studies across media forms to demonstrate how representations of seeds come to resemble the media in which they are embedded: seeds are screened, read, and played. George Miller’s Hollywood full-length feature Mad Max: Fury Road (2015) and Wanuri Kahiu’s independent short Pumzi (2009) deploy the visual and narrative aspects of cinema to cement the formal and phenomenological alignment between media and seeds. Ruth Ozeki’s All Over Creation (2003) and Diane Wilson’s The Seed Keeper (2021) explore seeds in the context of food systems both modern and traditional, cultural legacies both colonial and inherited, and stories both personal and (supra-humanly) collective; these contemporary realist novels exemplify and perform the inextricable relationship between seeds and language. Considering seeds in Eric Barone’s independent videogame Stardew Valley (2016) illuminates the game’s status as more than just a farming simulator and showcases how Stardew’s sandbox affordances—its procedural rhetoric and metagame potentialities—find their parallel in seeds themselves. This dissertation is both critical intervention and engaged participation in the phenomenon by which, to borrow from W.J.T. Mitchell, our relationship to both seeds and “media is one of mutual and reciprocal constitution: we create them, and they create us.
Agentic Access Control Workflows: Towards Automated Database Deployment
No full textIn every enterprise database, administrators must define an access control policy that specifies which users have access to which tables. Access control straddles two worlds: policy (organization-level principles that define who should have access) and process (database-level operations that actually implement the policy). Assessing and enforcing process compliance with a policy is currently a manual and ad-hoc task. In this thesis, I show that LLMs can be used to generate DB access control implementations from policy documents effectively. To achieve this, this thesis first proposes a novel policy linting usage model for access control involving not only synthesis of access control implementations from policy documents, but auditing of implementations against policy documents for effective debugging of database access control. To perform synthesis and auditing accurately, this thesis then proposes DePLOI (Deployment Policy Linter for Organization Intents), a LLM-backed system leveraging access control-specific task decompositions to accurately synthesize and audit access control implementation. DePLOI leverages novel access control-specific task decompositions, prompting strategies, and a novel access control model that serves as an input policy representation for DePLOI, which I call Intent-Based Access Control for Databases (IBAC-DB). Lastly, while access control policy can be expressed using IBAC-DB, I recognize that organizations will still need to write security policy documents. Therefore, to make DePLOI end-to-end, this thesis shows that as long as text related to access control is roughly structured in a policy document, it is possible to create an accurate ACM Extraction Agent via an agentic training workflow. This output ACM can then be given to DePLOI to synthesize and audit access control implementations
Developing Efficient Frameworks for Coalescent-Based Inference in Population Genetics
Get PDFThe exponential growth in genomic datasets has created unprecedented opportunities to study evolutionary processes, but existing population genetic inference methods face critical scalability and interpretability challenges. While the coalescent framework provides a powerful and interpretable backward-in-time approach for connecting observed genetic variation to underlying evolutionary forces, it can be quite computationally inefficient and statistically intractable, especially when dealing with large numbers of spatially distributed individuals or the effects of selection. As a result, current methods rely on low-dimensional representations of the coalescent process for efficient inference. This creates an urgent need for efficient inference frameworks that maintain direct connections to mechanistic evolutionary theory while scaling to modern datasets. This dissertation addresses these challenges via the development of three three novel frameworks that advance coalescent-based inference by bridging forward-time evolutionary models with backward-time genealogical approaches. First, I present a spatial population genetics method that extends isolation-by-distance models to jointly infer local migration surfaces and long-range genetic connections, addressing limitations in current approaches that ignore non-local gene flow patterns. Second, I develop a framework for inferring natural selection from paired data of allele frequency and age estimates by leveraging forward-in-time diffusion approximations. This approach produces unbiased selection coefficient estimates under realistic demographic scenarios, and through this framework I find that the ages of common variants are more useful in distinguishing stronger selection coefficients, following previous results from frequency-based approaches and reconciling claims from recent statistical genetics studies for traits under strong directional selection. Third, I extend this inference to the Ancestral Selection Graph (ASG) framework, developing rates for selection strength estimation that utilize forward-in-time transition probabilities. While this approach shows promise for faster inference compared to structured coalescent methods, I demonstrate that the signal is primarily driven by age information, indicating the need for further exploration in this space. However, this work outlines a potential way to bridge the gap between diffusion-based selection theory with modern tree-based inference methods. Each method is validated through extensive simulations. Importantly, the frameworks presented here advance our ability to extract interpretable evolutionary insights from large-scale genomic datasets efficiently, with applications ranging from statistical genetics to conservation genetics