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Optimizing The Design And Implementation Of Peer Support Interventions For Adolescents Living With Hiv In Sub-Saharan Africa
Get PDFAdolescents living with HIV (ALHIV) in sub-Saharan Africa (SSA) face multiple challenges which exacerbate their risks for treatment failure and poor psychosocial outcomes. Peer support interventions can be a mechanism to potentially improve their health outcomes. The purpose of this dissertation was to use innovative approaches to design and evaluate peer support interventions for ALHIV in sub-Saharan Africa, which were explored in three ways. First, an integrated review was conducted to understand the state of the science regarding the efficacy of peer support interventions in improving psychosocial and treatment outcomes among ALHIV in SSA. Second, a hybrid inductive-deductive thematic approach was used to identify implementation determinants regarding the peer delivery of a brief psychological intervention (i.e., Friendship Bench) among ALHIV in Gaborone, Botswana. Our findings provide eight implementation determinants (i.e., six barriers and two facilitators) to consider in future adaptations of Friendship Bench for ALHIV. The six barriers identified were client accessibility, parent disapproval, lack of financial resources, counselor psychological wellbeing, client reticence and confidentiality concerns, and scheduling procedures. The two facilitators were counselors’ perceived value of the intervention and peer delivery of counseling. Third, a behavioral economics design approach (i.e., NUDGE) was used to identify behavioral barriers to antiretroviral therapy adherence among ALHIV in Eswatini, and subsequently design intervention prototypes that peer lay health workers (i.e., expert clients) can use to address these barriers. The following barriers were identified and validated by expert clients: fear of public and interpersonal disclosure of HIV status, anger and lack of acceptance related to delayed HIV disclosure among parents, refusal to receive adherence instructions from adults, and psychological barriers related to food insecurity. Lastly, prototype ideas to address these barriers were developed and vetted by expert clients. Overall, expert clients favored four prototype ideas that they believed were feasible to implement at a low cost: commitment contracts, message framing, group regret lotteries, and messenger type interventions. The overall findings and insights from this dissertation provide the preliminary steps for future work utilizing behavioral economics and implementation science to optimize peer support interventions for ALHIV in SSA
Archipelagic potentials : Infrastructures, Education, And Labor In Indonesia
No full textAmidst the Indonesian government’s stated ambition to become a top global economy by 2045, talk of potensi, or “potentiality,” is everywhere: from policymakers who identify their goals as “unleashing the country’s economic potentials” to rural youth who express their hopes to “open their inner potentials.” This dissertation takes the ubiquitously present and multifaceted concept of potentiality as an analytical entry point into exploring the relationship between people’s descriptions of latent capacities, warnings of threats, and aspirations for particular futures and processes of development policy and practice. Drawing on the anthropological literatures on valuation, market making, and education, this dissertation studies how policymakers, educators, and students at various societal scales in Indonesia engage in everyday practices of valuation as they take part in the collective actualization of a development vision.
Beginning in Jakarta, Part I focuses on a global network of policymakers who regularly declare that Indonesia’s future welfare depends on (1) realizing the existing, but as-yet undeveloped “economic potentials” of the country’s margins; and (2) ensuring the positive potentials of Indonesia’s burgeoning “demographic bonus” subsumes the negative ones. These policymakers position the vocational “skilling” of rural youth as necessary means of driving economic growth. Turning next to Bone, South Sulawesi, a so-labeled “marginal” locale, Part II examines the everyday activities at a fisheries vocational high school, where educators both respond to national-driven demands as they prepare a specific kind of “work-ready” graduate: “the potentializing student.” The part concludes by exploring how young people evaluate their own potential futures vis-à-vis the multi-scalar claims made about the potentials of their nation, their region, and their own lives.This dissertation contributes to discussions about development by highlighting the complex cultural work that goes into enacting policy visions. Furthermore, it identifies two key ramifications for the future-potential-oriented societal push observed in Indonesia: (1) the communal deflection of social ethics in the present through justifications for future good; and (2) the social abandonment of societal members who are deemed surplus to achieving the country’s vision of success
Integrated Diamond-Based Devices For Quantum Sensing And Communication
No full textThe nitrogen-vacancy (NV) center in diamond has been integral to the advancement of quantum technologies. It has enabled key demonstrations in quantum networks and distributed quantum computing, as well as impressive proof-of-concept devices in nanoscale, sub-cellular imaging and sensing. The NV center | a point defect in diamond with an optically addressable electron spin | boasts several advantages such as long coherence times and quantum control in ambient conditions. At the same time, the NV center still faces significant engineering challenges in the realization of scalable quantum devices. The high-refractive index of diamond in the visible spectrum results in inefficient photon collection, and the NV center\u27s sensitivity to charge and spin fluctuations at surfaces and interfaces necessitates deeply embedded NV centers for coherence-limited applications, which further worsens readout efficiency. The challenging optical interface has necessitated the use of high numerical-aperture objectives and free space optics, which are non-ideal components for scalable devices. On the other hand, benchtop frequency synthesizers and sequence generators typically used in laboratory experiments inhibit the packaging of NV centers for deployment outside of laboratory environments. This thesis focuses on the realization of integrated quantum devices using the NV center and targets miniaturization of the host crystal, the optical interface, and quantum control sequence generators. First, it discusses efforts and progress in realizing chemically active quantum sensors based on NV centers embedded in nanodiamonds. Following, it presents the miniaturization of collection optics through the coupling of an immersion metalens fabricated on bulk diamond to a single NV center in the crystal. Finally, it lays out performance considerations for integrated sequence generators to preserve the NV center\u27s coherence properties, and demonstrates quantum control at room temperature of a NV center using a CMOS control signal generator. To conclude, this thesis discusses future potential for further integrating and miniaturizing diamond-based quantum devices
The Effects Of Migration On Evolutionary Dynamics In Natural Populations Of Drosophila Melanogaster
No full textUnderstanding how major mechanisms of evolution, i.e. selection, gene flow, mutations, and genetic drift, shape natural populations is a major goal of evolutionary biology. Due to climate change, the environment and ranges of species are changing rapidly. Through rapid adaptation, populations can potentially respond to rapid environmental changes. Yet, how gene flow and rapid adaptation work together to shape natural populations is still an open question in biology. North American populations of Drosophila melanogaster provide a strong model to investigate this relationship as they exhibit latitudinal clines, low levels of variation, and rapid adaptation to environmental parameters that change rapidly with season.
In this dissertation, I investigate the relationship between migration and rapid adaptation using D. melanogaster as a model system. I first demonstrate that migration may facilitate adaptation due to epistatic interactions through highly replicated laboratory and field experiments where evolutionarily realistic populations are manipulated to simulate a single migration event. I exposed populations to different temperature regimes and used parallelism in responses to determine the direction of the adaptive response. By comparing the responses of populations that received migration to controlled gene flow events and simulated expectations, I showed that migration events might facilitate adaptive responses. Finally, to demonstrate the ecological relevance of migration, I used population genetics and Bayesian inference methods to estimate the connectivity between geographically separate natural populations of D. melanogaster and I showed that mid- and long-range connectivity is likely.
These results together demonstrate that migration can be an ecologically realistic mechanism that facilitates adaptive response in nature. The adaptive outcome depends on the genetic architecture of the fitness-associated traits that respond to dynamic selection pressures. This work integrates the phenotypes and their genotypic architectures to explain the evolutionary responses through highly replicated experiments in the laboratory and field. Together, this work represents a novel contribution to the analysis of evolutionary impacts of migration and gene flow in natural populations
Role Of Type Ii Phosphatidylinositol 4-Kinases In Endosomal Tubule Dynamics During Melanosome Biogenesis
Get PDFMelanosomes are pigment cell-specific lysosome-related organelles (LROs) in which melanin pigments are synthesized and stored. Melanosome maturation requires biosynthetic delivery of melanogenic enzymes (e.g. TYRP1), transporters (e.g. OCA2), and SNAREs (e.g. VAMP7) from early endosomes (EEs). One essential pathway requires the multisubunit complex, BLOC-1, on EEs to generate tubular transport carriers to deliver cargos to melanosomes. The molecular mechanisms by which BLOC-1 facilitates tubule formation are not entirely known, but several studies suggest that phosphatidylinositol-4-phosphate (PtdIns4P) and the type II PtdIns-4-kinases, PI4KIIα and PI4KIIβ, may play a role. Moreover, PI4KIIα and PI4KIIβ interact respectively with AP-3 and AP-1, both of which control BLOC-1-dependent cargo sorting. We hypothesized that type II PtdIns-4-kinases support BLOC-1-dependent tubule formation via PtdIns4P to regulate melanosome biogenesis. We found that depletion of either PI4KIIα or PI4KIIβ in melanocytes reduced melanin content and impaired the melanosomal localization of TYRP1, OCA2, and VAMP7 by immunofluorescence microscopy (IFM) and bright-field microscopy. TYRP1 was largely mislocalized to late endosomes/lysosomes in PI4KIIα- or β-depleted cells, and not exclusively to EEs as observed in BLOC-1-/- melanocytes. This suggested that type II PtdIns-4kinases are not absolutely required for BLOC-1-dependent cargo exit from EEs but function downstream of BLOC-1. Consistently, depletion of PI4KIIα or PI4KIIβ in BLOC-1-deficient cells did not affect TYRP1 accumulation in EEs by IFM, and depletion of PI4KIIα or PI4KIIβ in wild-type melanocytes did not affect BLOC-1 association with membranes by subcellular fractionation. Rescue studies revealed that enzymatic activity and AP-binding abilities of both PI4KIIα and PI4KIIβ are necessary for TYRP1 localization to melanosomes. Live cell imaging showed that PI4KIIα associates with tubules from the onset of tubule formation, whereas PI4KIIβ accumulates after the tubule has formed, suggesting that PI4KIIα acts earlier than PI4KIIβ. Depletion of either PI4KIIα or PI4KIIβ reduced PtdIns4P on endosomal tubules and impaired tubule elongation. These data together suggest that PI4KIIα and PI4KIIβ function sequentially and non-redundantly downstream of BLOC-1 by generating PtdIns4P on endosomal tubules during tubule elongation and that both isoforms are necessary for efficient melanosome contact and content delivery to melanosome. Our study demonstrates the important roles of PtdIns4P and both type II PtdIns-4-kinases in BLOC-1-dependent tubular cargo transport for melanosome biogenesis and extends the cohort of effectors required for LRO biogenesis
Electronic Structure Theory, Electronic Friction, And Berry Curvature: An Important Frontier Between Chemistry And Physics
Get PDFNonadiabatic dynamics play an important role within electron transfer processes, excitation energy transfer events, the linear/nonlinear spectroscopy of molecular open quantum systems, and molecular junction quantum transport. All of the phenomena listed above can involve multiple electronic states, and the transfer rates between such states can be significantly enhanced or suppressed by including the dynamics of the nuclear degrees of freedom. In order to simulate the relevant nonadiabatic dynamics, a precise and computationally feasible electronic structure theory is necessary. Most importantly, the theory has to be simple enough so that analytic gradients and derivative couplings, which are fundamental building blocks for running nonadiabatic dynamics, can be achieved. In the first half of this dissertation, we propose a novel electronic structure theory which is based on HF/CIS or DFT/TDDFT but solves a long-standing issue about the topology of potential energy surfaces near conical intersections as calculated by these popular methods. In the second half of the dissertation, motivated by recent experiments about chiral induced spin selectivity, we turn to systems of a molecule attached to a metal lead(s). We refine the friction tensor formalism (which utilizes a nonequilibrium Green’s function technique) to get the “nuclear” Berry curvature effects which is a result of nonadiabaticity. We demonstrate that even in the presence of electron baths, the nuclear Berry curvature effects can be as important as the friction applied to the nuclear wave packet. We further include spin degrees of freedom to show that, through spin-orbit interactions and nuclear Berry curvature effects, different spin carriers behave differently in a molecular junction, resulting in spin polarization
Executable Denotational Semantics With Interaction Trees
Get PDFInteraction trees are a representation of effectful and reactive systemsdesigned to be implemented in a proof assistant such as Coq. They are equipped with a rich algebra of combinators to construct recursive and effectful computations and to reason about them equationally. Interaction trees are also an executable structure, notably via extraction, which enables testing and directly developing executable programs in Coq. To demonstrate the usefulness of interaction trees, two applications are presented. First, I develop a novel approach to verify a compiler from a simple imperative language to assembly, by proving a semantic preservation theorem which is termination-sensitive, using an equational proof. Second, I present a framework of concurrent objects, inheriting the modularity, compositionality, and executability of interaction trees. Leveraging that framework, I formally prove the correctness of a transactionally predicated map, using a novel approach to reason about objects combining the notions of linearizability and strict serializability, two well-known correctness conditions for concurrent objects
The Relationship between Leader Behaviors and Employee Engagement in a Virtual Work Environment
No full textThis mixed-method dissertation examined the relationship between leaders\u27 behavior and employee engagement in virtual work environments. For leaders, the virtual work environment, a shift caused by the COVID-19 pandemic, represents a paradigm shift, pushing them to reconsider their engagement-related actions. The literature review for the dissertation examined pre- and pandemic academic studies on virtual working, engagement, and leadership. The scarcity of research on engagement in virtual workplaces underscored the significance of this study. As a result, the key research questions focused on determining which leader behaviors promote employee engagement for virtual workers and which employee-related aspects particular to virtual working must leaders address when aiming to increase employee engagement. The exploratory sequential mixed-method approach gathered both qualitative and quantitative data, combining them to generate both a deep qualitative understanding and more specific quantitative generalizations. A new survey instrument was created using the qualitative analysis as an input for item production, and statistical processing confirmed the new instrument\u27s validity and reliability. The quantitative analysis was able to filter, generalize and crystalize the inputs from the qualitative data. The study offers new leadership insights on the elements and behaviors that have the greatest impact on employee engagement when people work virtually. It also contributes to academic scholarship by designing and evaluating a new survey instrument that focuses solely on factors that influence virtual employee engagement
Romance Auctoritas in Le livre du cuer d’amours espris and Jehan de Saintré
No full textThis dissertation asks whether, by the end of the Middle Ages in France, the romance genre had gained literary authority, or auctoritas, and, if so, how it had gained it and what the social impact of this auctoritas was. This line of questioning is executed through a study of two mid-fifteenth-century romances: René d’Anjou’s Livre du Cuer d’Amours espris and Antoine de la Sale’s Jehan de Saintré. These two works, written near the end of the Middle Ages when romance was at the height of its popularity and influence, heavily imitate and cite earlier romances, and in so doing, offer an insightful response to the genre and its position in French courtly society. They confirm that while the genre may not have had a traditional scholarly auctoritas, it certainly had a level of courtly auctoritas, exemplified by the literary traditions of the Roman de la Rose and Prose Lancelot. These literary traditions exerted cultural auctoritas as they came to functional as behavioral and moral guides in the courtly disciplines of love and chivalry. Furthermore, this study argues that two principle writing strategies served to establish romance auctoritas despite the fictionality of the genre. The first, exemplified by the Roman de la Rose and imitated by the Livre du Cuer, was to present the romance’s fictions as allegory, with the argument that they covered hidden moral truths. The second, exemplified by the Prose Lancelot and imitated by Jehan de Saintré, was to deny the fictionality of the romance, and to instead present it was a work of historia. The two late-medieval works at the center of this study each employ one of these two romance strategies in an attempt to build their own auctoritas, even while criticizing the socially harmful influence of romance ideology. In so doing, they confirm the genre’s courtly auctoritas and reveal the strategies employed to achieve it
Teaching with Intention: Using WOOP to Support Social-Emotional Learning in the Classroom
No full textAmerican society and schools are increasingly recognizing the importance of tending to children’s social-emotional learning (SEL). According to social learning theory, one way children learn social-emotional skills, knowledge, and mindsets is by observing others—including their teachers. It is thus important that teachers model the same social-emotional practices that they hope to cultivate in students. This qualitative action research study explores how one psychological strategy—namely, intention-setting—can support teachers’ social-emotional development. As part of a multi-day, online professional development (PD) program, 28 teacher-participants used the WOOP (Wish-Outcome-Obstacle-Plan) framework to set intentions around their SEL goals, journaled about, and reflected on their experience. Three caselets tell the story of what this process looked like for three different teachers. Using a combination of inductive, deductive, and collaborative coding techniques, this study then zooms in on the intention-setting phase to take a close look at teachers’ SEL goals, and the reflection phase to see what teachers reported learning and feeling as they worked towards those goals. Finally, it looks across the entire intention-setting, enacting, and reflection process to illuminate the challenges and supports that participants encountered along the way. This analysis reveals that teachers face a wide range of social-emotional challenges in their classrooms and schools, and have an equally wide range of SEL goals; using WOOP to set and plan for these goals can lead to many (though not exclusively) positive learning and emotional outcomes; and the intention-setting process can be difficult, though doing it with others can help. These findings and their implications speak to education researchers and applied psychologists interested in if and how intentionality supports social-emotional learning and teaching; as well as teacher educators, PD providers, and perhaps most importantly, teachers looking for ways to support healthy SEL