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Liturgy of Empire: Reading the Mozarabic Rite in Early Modern Europe, 1500–1800
No full textLiturgy of Empire examines the European reception of the neo-Mozarabic rite created under the patronage of the Archbishop of Toledo, Francisco Jimenez de Cisneros (1495-1517), in relation to the history of the Mozarabs of Toledo, the development of bibliophilia and libraries, the scholarly study of medieval liturgy, and the crusading ideology of Spanish expansionism in the Mediterranean.
During the emergence of Spain’s global empire, the editions of the Mozarabic rite entered collections throughout Europe. The provenance of the copies (studied here for the first time) reveals their mediation of knowledge about Iberian history and the political contexts for their acquisition
Extending the availability of living allogeneic heart valves for transplantation
No full textThere remains an urgent clinical need to develop durable heart valve replacements which can act as life-long substitutes for the native heart valve, especially for pediatric patients wherein the current standard of care is multiple reoperations to repair or replace failed valve prostheses throughout a child’s lifetime. These reinterventions are often required within just months of the valve replacement’s original implantation. This is because there are currently no valve prostheses with the capacity for growth or self-repair. Both bioprosthetic valves (including cryopreserved human allografts, which represent the historic gold-standard for pediatric patients) and mechanical valves suffer from limited durability and are unable to support the somatic growth of a child.
Living heart valve transplantation is a recently introduced surgical technique wherein valvular allografts are procured from a heart deemed unsuitable for orthotopic transplantation or from a living valve donor who is receiving a heart transplant for a non-valvular indication. In heart valve transplantation, these living valves are semi-emergently transplanted in the recipient, with the core advantage of functioning as a viable, growth-capable valve. The in vivo adaptive growth and durability of living heart valve transplants is currently being studied in single and multi-center clinical studies, with promising early outcomes. However, there remain key translational challenges to this technique’s implementation – namely, lack of donor availability as well as the time, resource, and logistic constraints involved in urgent transplantation. These challenges are exacerbated by the difficulties of donor-recipient size matching in pediatric patients.
In this dissertation, we therefore work towards establishing a strategy for the storage and preservation of living allogeneic valves, with the hypothesis that integrating physiologic biochemical and mechanical cues will enable the preservation of valvular tissue physiology ex vivo. In Aim 1, we develop a custom preservation solution aimed at preserving valvular tissue viability. We thoroughly evaluate the preservation solution’s capacity to maintain valvular leaflet and pulmonary artery viability, metabolism, microarchitecture, and cell physiology for up to 7 weeks ex vivo. Our experimental model employed freshly sourced porcine valves that had been subject to the upper limit of static cold storage currently used in clinical practice. We found that our preservation solution could preserve valvular viability and metabolism for at least 7 weeks, with maintenance of key phenotypic markers of valvular interstitial cells. However, the leaflet microarchitecture began to degrade by 3 weeks ex vivo, with increasing collagen content.
Building on these results, we sought to integrate physiologic mechanical cues to more effectively preserve valvular microarchitecture. In Aim 2, we designed, built, and tested a custom bioreactor for the storage of valvular allografts. With clinical translation as a primary goal, a key design specification of our bioreactor was to avoid the use of a pump. We created a low-cost, user-friendly, compact system which was composed of a closed loop, wherein the valve is maintained in a valvular housing chamber and fluid flow through the valve is dependent on axial rotation of the bioreactor. We validated that rotation could introduce native-like open/close cycles in porcine valves and obtained fine-tuned control over the hydrodynamic environment by manipulating the bioreactor’s rotation protocol. Finally, we demonstrated the capacity to maintain valvular viability in the bioreactor for up to 4 weeks. We found that valves exposed to mechanical stimulation demonstrated maladaptive remodeling, characterized by leaflet retraction and fibroblast proliferation. Therefore, we then performed a parameter-controlled study which identified a unique biochemical treatment which could prevent valvular fibrosis in response to mechanical stimulation ex vivo.
In Aim 3, we evaluated the in vivo response to living valvular allografts in the preclinical and clinical settings. We established a porcine model for heart valve transplantation and then applied this model towards evaluating the impact of static cold storage on valvular allograft function. We found that fresh valve transplants demonstrated preserved function for 2 months of follow-up, versus a valve that had been subject to 4 weeks of static cold storage which showed severe insufficiency and diffuse calcification throughout the pulmonary artery on explant. We next investigated clinical outcomes following heart valve transplantation at Columbia, following two patients who received “domino” heart valve transplant at our center. Our outcomes demonstrated maintained valve function with adaptive valvular growth in both patients. We also report the first-ever evidence of immunosensitization following heart valve transplant, with both patients developing donor specific antibodies within 100 days post-transplant.
Collectively, this dissertation functions as a foundation for normothermic storage and preservation of living allogeneic valves through integration of key homeostatic signals in the ex vivo environment. Moving forward, the strategy developed in Aims 1 and 2 will be evaluated in vivo, as per the preclinical model establish in Aim 3. In tandem, we are continuing to evaluate the in vivo performance of heart valve transplantation via multicentric studies including centers from across the United States, as well as through the development of a dedicated registry aimed at the long-term follow up of heart valve transplant recipients
The Possiblities of a Somatic Movement Education Pedagogy for the Early Childhood Dance Education Class: An Inclusion of Personal Literacy Through Dance Education
No full textThis qualitative, pragmatic, practitioner inquiry employed the Mosaic Approach to address the problematic omission of somatic-constructivist principles—the study of one’s lived experience, encompassing body, mind, and spirit (Hanna, 1970)—in the development of early childhood dance education pedagogy.
Data were collected from children aged 4.5 to 5 years who participated in a series of eight somatic movement adventures, designed as multisensory stories, to explore somatic concepts and anatomical principles in a dance education class setting. Data collection methods included observation and field notes, children’s drawings created in response to prompts, stimulated recall, Leuven scale ratings (Laevers, 1994), and memoing.
The findings of this research were that children who participated in the somatic movement adventures, building on their unique prior knowledge and learning affinities, created self-to-self stories. These stories demonstrated somatic awareness evidenced through increased proprioceptive awareness, expanded periods of independent dancing, expressions of inner felt sensations in concrete objects, articulated responses, and the concretization of abstract concepts, thereby developing their personal literacy.
The data were reported as a synthesis in the narratives of three focal children, Tory, Nora, and Leo. Across the data, two key pedagogical findings emerged: the co-creation of rapport and a community of somatic practice, and the pedagogical stance of non-interference, which were identified as the most significant in supporting learning possibilities in a somatic pedagogy for the early childhood dance education class
The Little Things, They're Not So Little: Examining Features of and Responses to an Early Childhood Art Museum Program
No full textThis study investigates how a highly regarded early-childhood art museum program engages young children (ages two through four) and their caregivers. It examines what pedagogical features shape these engagements and what participants value about their experience in the program. Using a qualitative case‐study design, triangulation of data was used involving observations of three program sessions, interviews with caregiver participants, program educators and the program administrator as well as a review of program descriptions. Data was transcribed, coded, and analyzed alongside relevant literature where themes emerged across these sources.
Findings demonstrated that the program fostered intrafamily bonding and nurtured connections among participant caregivers. Relational and embodied experiences were highlights of the early childhood program as children and adults engaged with materials, artworks. one another and the museum space through gesture and movement. Additionally, caregivers often acted as co-learners rather than merely facilitators. This was attributed to a thoughtfully designed environment and program structure that supported participants, many of whose children were first time museum goers. Factors such as educator responsiveness, validation of unexpected uses of materials, reframing of frustrations as discoveries and inviting multiple modes of participation were responsible for contributing to the expansion of children’s and caregiver’s sense of agency.
This study carries implications for how art museums design and facilitate programs for young children and their caregivers. It suggests that when programs emphasize embodied, relational, and intergenerational engagement, museums can move beyond traditional, adult-centered approaches to create more inclusive and meaningful spaces for family learning. In summary, this study identifies early childhood art museum education as an intergenerational and empowering practice, despite constraints that may be imposed on the field, fostering connection in places where certain barriers may exist
Impact of Trauma-informed Psychologically Safe Debriefing Method on Attitudes and Debriefing Experience in Nursing Students Following an End-of-Life Simulation
No full textA student’s first experience with death can have a profound influence on their attitudes toward the care of dying patients. Undergraduate nursing students often feel unprepared for end-of-life (EOL) care. Despite recommendations to teach EOL care, current methods used in nursing curricula are often insufficient to prepare students for the realities of caring for dying patients and their families.
This study examined differences in attitudes toward the care of dying patients and the debriefing experience of active participants and observers using the Trauma-informed, Psychologically Safe (TiPS) debriefing method compared to a traditional Plus-Delta debriefing after an EOL simulation. Guided by Kolcaba’s Comfort Theory, this multisite, quasi-experimental study employed a two-group, pretest-posttest design with an equivalent comparison group.
A total of 145 final year traditional Bachelor of Science in Nursing students either actively participated in (n = 60) or observed (n = 85) in an EOL simulation that included the withdrawal of life support and the implementation of intensive comfort measures. Following the simulation, students participated in either the TiPS debriefing or a Plus-Delta debriefing. Data were collected at baseline and immediately postintervention using the Frommelt Attitude Toward Care of the Dying- Form B, and the Debriefing Experience Scale, and role selection.
Data were analyzed using descriptive statistics, Mann-Whitney U tests, independent samples t tests, and two-way analysis of variance. There was a marginally significant difference in attitudes toward the care of dying patients (p = .05) from pretest to posttest suggesting a potential but not pronounced impact from the simulation. Attitudes toward the care of dying patients showed similar improvement in both groups, indicating no differential effect of the debriefing method. However, participants in the TiPS debriefing group had a statistically significantly more positive debriefing experience than those in the Plus-Delta group. There were no differences noted in attitudes or debriefing experience between active participants and observers.
The findings also revealed that debriefing method and role did not jointly affect attitudes toward the care of dying patients. Students’ attitudes toward the care of dying patients can improve after an EOL simulation irrespective of debriefing methods used. The TiPS debriefing method is favored by students and effectively improves their debriefing experience after an EOL simulation, regardless of participant role. Nurse educators can optimize their resources by including an observer role, if all students participate in the structured debriefing
Advancing Climate Resilience For Agriculture In Senegal: AgMIP-Supported Policy And Action
No full textThe study titled "AgMIP Demand-Scoping Study in Sub-Saharan Africa," conducted by the Agricultural Model lntercomparison and Improvement Project (AgMIP) and led by researchers from IPAR, engaged representatives from the Ministry of Agriculture, Food Sovereignty and Livestock (MASAE), the Ministry of Environment and Ecological Transition (METE), ISRA, ANACIM, AICCRA, farmers’ organizations, and development partners through interviews and two workshops held in Ghana and in Senegal. The interviews asked policy and decision makers what science-based information they need. The workshops prioritized the science needs communicated in interviews and discussed how to improve collaborations between researchers and stakeholders to co-produce the science.
This policy brief summarizes key insights from the interviews and the workshops. It illustrates how AgMIP’s Integrated National to Regional Assessments (INaRA) framework can be advanced by integrating the Rural Investment and Policy Analysis (RIAPA), a national economic model developed by the International Food Policy and Research Institute (IFPRI), into INaRA. This enhanced framework can provide the evidence base that policy and decision makers are asking for to help advance policy and investment responses to the climate crisis and to help transform the agricultural sector in Senegal
A novel approach for direct lithium extraction from alkali metal cations in brine mixtures using thermally switchable solvents
No full textThis study presents a proof-of-concept for switchable solvent selective extraction (S3E) for direct lithium extraction from brines. S3E utilizes an amine solvent with thermally switchable hydrophilicity to extract Li+ and water from the brine, and a modest temperature swing toggles the solvent to its hydrophobic state, releasing a purified lithium product stream and regenerating the solvent. S3E demonstrated a consistent preference for lithium across amines with different chemical structures, achieving Li+/Na+ selectivities as high as ≈10. The selectivity for lithium was maintained even when challenged with Li+ concentrations 1,000× lower than Na+ or K+, whereas Li+/Na+ and Li+/K+ selectivities for a simulated Salton Sea geothermal brine are ≈13 and ≈24, respectively, with magnesium completely removed as Mg(OH)2 precipitates due to the basicity of the amine solvent. Furthermore, repeated semibatch extraction cycles reusing the solvent demonstrated practical Li+ recovery yields (40% after four cycles) and solvent regenerability while preserving selectivity.
Keywords: direct lithium extraction, DLE, switchable solvents, alkali metal cation selectivity, critical materials, ion selective separation, geothermal brines, liquid-liquid extraction, solvent extractio
GRID3 COD - Travel Time Friction Surface v1.0
No full textThe dataset consists of two surfaces:
- Walking cost surface: Applies walking speeds across the entire surface, adjusted for slope and elevation.
- Mixed-mode cost surface : Applies motorized speeds on roads and walking speeds in all other areas.
Keywords: Travel tim
Room For The River Waal in Nijmegen
No full textThe Room for the River Waal project in Nijmegen is part of the Dutch national Room for the River program aimed at improving flood safety while enhancing spatial quality through nature-based river restoration. Triggered by severe near-flood events in the 1990s, the project created a secondary river channel, relocated dikes, and formed a river island that supports recreation, urban development, and ecological functions. Implemented through multi-level governance and an extensive participatory planning process, the project transformed initial public resistance into broad acceptance and local pride. Beyond flood mitigation, the initiative strengthened urban connectivity, stimulated economic development, and improved landscape quality and well-being. The project demonstrates how multifunctional nature-based solutions can simultaneously advance climate resilience, urban livability, and stakeholder legitimacy in riverine cities
Wastewater Treatment in Abuja
No full textRapid urbanization in Abuja has outpaced the capacity of its centralized wastewater treatment systems, leading to low coverage and environmental health risks. The city faces challenges including insufficient infrastructure, limited skilled personnel, and inadequate policy frameworks, which are compounded by climate change impacts. Implementing sustainable technologies, circular economy principles, and targeted policy interventions is essential to improve wastewater management, enhance resilience, and support urban development in Abuja