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5.2 Solidarity Bioeconomy
Get PDFThis entreaty presents a novel vision for biotechnological development based upon a democratic and community-centered innovation ecosystem, the solidarity bioeconomy. Rooted in the principles of democratic ownership, community science, and equitable wealth creation and the practice of Indigenous biotechnology, solidarity bioeconomy networks are composed of community biology labs and cooperative enterprises among other alternative ownership enterprises (AOEs). Various ways to structure for-profit enterprises are discussed along with potential challenges and potiential solutions. The entreaty ends with specific calls to actions, ways to immediate support, along with model examples of existing organizations (ICV, Cooperative Wine Institute). Endorsing this entreaty represents an acknowledgment of solidarity bioeconomy as a foundational concept for biotechnology development and a commitment to growing solidarity bioeconomy networks in bioregions around the world.This entreaty was created as part of The Spirit of Asilomar and the Future of Biotechnology summit (February 23-26, 2025) in Pacific Grove, CA
Promised DE&I, Experienced Microaggressions: Investigating Psychological Contract Violation and (Dis)Trust in Leaders and Organizations
Get PDFResearch suggests that employees form psychological contracts (i.e., unwritten, mutual obligations between employers and employees) about diversity, equity, and inclusion (DE&I; Lee et al., 2021; Yueng & Sheh, 2020), yet little is known about how encounters with subtle racial discrimination at work may trigger violations of these contracts and subsequently influence relational outcomes. Grounded in psychological contract theory (Rousseau, 1989), this project investigates whether and why experienced and witnessed workplace racial/ethnic microaggressions, a subtle form of discrimination that targets racial/ethnic minority group members, may relate to lower trust and higher distrust in leaders and organizations via psychological contract violation. Additionally, this study examines two boundary conditions: (a) the moderating effect of DE&I psychological contract strength on the relationship between microaggressions and psychological contract violation, and (b) the moderating effect of satisfaction with leader responses to microaggressions on the relationship between psychological contract violation and the focal outcomes. Panel data collected from 315 employees across 8 weekly surveys was analyzed using multilevel structural equation modeling (MLSEM). Results suggest that across participants, psychological contract violation mediates the relationship between microaggressions and the focal outcomes. No support emerged for the hypothesized boundary conditions. Theoretical implications and practical recommendations are discussed
High-throughput robotic strategy to implant ultraflexible neural devices
No full textNeural interfaces have shown remarkable potential in restoring sensory and motor function,
treating neurological disorders, developing technologies, and studying cognitive mechanisms.
Among neural recording and stimulation techniques, Micro-Electrode Arrays (MEAs) offer
the most significant temporal and spatial span, and recent advances in ultraflexible MEAs
have allowed for minimal foreign body response, thus improving the longevity and quality of the recorded signals. However, ultraflexible MEAs surgeries represent a considerable
challenge, even after comprehensive training, and carry the potential risk of inducing tissue damage or infection, ultimately contributing negatively to the performances of neural
probes. To overcome surgical hurdles, I present a high-throughput robotic strategy automating the insertion of up to 32 ultraflexible neural probes simultaneously. The system permits both speeds in the µm/s range for scarless insertion and high acceleration for
successful retraction of the shuttle wire. Tailored tungsten wire designs fabricated using
laser-micromachining enable tissue damage to be minimized. A user-friendly interface, with
real-time feedback and pre-coded procedures, enhances surgical precision and time efficiency
compared to non-assisted implantation strategies. Coupling functional imaging, laser scans,
and brain vasculature images, this innovative apparatus, achieving micrometer precision,
can target discrete layers and brain regions across the entire neocortex of rodents while
avoiding vascular structures. The successful development and deployment of this robotic
approach represent a first in inserting ultraflexible neural probes and holding promises of
streamlining a pivotal process in brain-computer interfaces
SHATTERED SKY / REMAINING LAND
No full textThis work explores the concept of the cycle of time—samsara, the endless loop of birth, death, and rebirth. My initial inspiration came from James Turrell’s Skyspace, where one gazes at the sky through a man-made aperture. I imagine piercing a hole through the sky—not merely to see beyond, but to witness the very shape of time itself: how clouds gather and dissipate, how stars revolve in the vast continuum of time, their distant light reaching us as remnants of the past.
This concept is embodied through breath—each inhale and exhale, each expansion and collapse manifesting across multiple musical dimensions, shifting between clarity and obscurity, fragility and solidity. The piece begins with a breath—the brass instruments exhale a sharp fp breath with the vowel transition [i:-ob], summoning the bass clarinet’s monologue. Its timbre drifts between the resonance of Japanese jiuta and the breath-like gestures of the shakuhachi, wavering between presence and nothingness—sometimes as weightless as a drifting cloud, other times as deep and resonant as an echoing cavern.
This cyclic motion of breath, expansion, and contraction operates both on various local levels and within the overall structure. The orchestra gradually layers sound upon sound, forming shifting textures like clouds breaking apart and reconfiguring, creating voids and fractures of varying densities. The distribution of registers reflects these “holes” in the sky, evoking a sense of vastness and space.
As time unfolds, the texture of the sound transforms—what begins as smooth and fluid gradually becomes rough, grainy, and resonant with noise, like the crackling surface of Ru ware as it develops its signature crackles. Ru ware, a rare Song Dynasty ceramic. This pale sky-blue glaze, described as “the color of a clearing sky after rain”, is defined by its cracks - the process of crackling shaped its identity, and clearing a sky rips the clouds apart.
All of this ultimately leads to a moment of collapse—when sound reaches its breaking point, the shattering of glass slices through the space, just as the Ru glaze finally cracks, its fragments falling into silence. Through this, I seek to question—what is our final fate? Do fractures and wounds define our existence? The sky has shattered, yet the land remains. And within that remaining land, the cycle begins anew
Multiview Linear-Array Photoacoustic Computed Tomography with Improved Elevational Resolution in 3D
No full textLinear transducer arrays are widely used in photoacoustic computed tomography (PACT) due to their lightweight design, cost-effectiveness, and handheld convenience. Despite these advantages, the inherent focusing design of the linear array results in anisotropic resolution in 3D. Specifically, the elevational resolution is approximately an order of magnitude worse than both lateral and axial resolutions. In this work, we propose multiview linear PACT (MvLPACT) to overcome this limitation. By combining the scanned data along the elevational direction from multiple angles, MvLPACT compensates for the deficiencies in elevational resolution. A multiview fast iterative shrinkage-thresholding algorithm (FISTA) based deconvolution, named MvFISTA-Deconv, is applied to the multiview scanning data to reconstruct 3D images. MvFISTA-Deconv integrates the high-frequency components that correspond to high-resolution features acquired from multiple angles into the reconstructed 3D images with improved resolution. Our proposed MvLPACT is evaluated on both phantoms and in vivo human experiments, showing a significant elevational resolution improvement up to 8-fold. Our results demonstrate MvLPACT as a powerful and robust technique for high-resolution 3D imaging in PACT applications, offering substantial advancements over traditional linear-array-based PACT
Essays on Unpaid Labor and Early Education
No full textThis dissertation explores gender dynamics, childcare decisions, and early childhood interventions through a series of studies that analyze household labor division, program evaluation, and policy impacts.
The first chapter presents a framework for analyzing how gendered preferences and bargaining power influence the division of unpaid labor in dual-earner households. Despite significant progress in women's education and workforce participation across OECD countries, women continue to perform a disproportionate share of unpaid labor. This paper addresses this imbalance by presenting a methodological contribution: a novel online choice experiment that combines stated-preference and revealed-preference data, enabling the separate identification of preferences and bargaining power under the assumption of a collective bargaining model for unpaid labor division. Preferences are identified from trade-offs between income, leisure, and childcare in hypothetical scenarios, while bargaining power is identified from the alignment of each spouse’s preferences with actual household decisions. Using a unique dataset of 265 dual-earner households with young children in South Korea, I estimate how gendered preferences, bargaining power, and childcare availability shape the division of unpaid labor. While both spouses show similar willingness-to-pay for the husband's first hour of parental care, preferences decline as his involvement increases. The husband's average bargaining power is 0.690 (on a 0 to 1 scale), but as the wife's relative wage rises, her influence grows. Counterfactual experiments show that as bargaining power equalizes, the gap in parental care time narrows. My framework supports various counterfactual analyses, such as adjusting household choice sets, to assess changes in the unpaid labor gap and inform policy.
The second and third chapters shift attention to early childhood interventions, beginning with an analysis of referral and evaluation patters in the Texas Early Childhood Intervention (ECI) program. This paper analyzes referral, evaluation, eligibility, and service patterns in the Texas Early Childhood Intervention (ECI) program using data from the universe of all 319,864 children born between 2015 and 2019, who were referred to the program in Texas. We provide descriptive statistics on referral categories, concerns, and age at referral, and highlight notable variations in evaluation rates across counties. Logit models reveal that all variables influence evaluation probabilities, with substantial cross-country differences. Through decomposition analysis, we explore whether these disparities stem from differences in referral characteristics or county-level evaluation processes, finding that evaluation practices across counties significantly impact those outcomes.
The third chapter evaluates the Parent-Child Education Program (PCEP) implemented by AVANCE and its impact on parental engagement in Hispanic communities in Southern Texas. The PCEP aims to enhance early childhood development and parental involvement through comprehensive intervention. Utilizing a Randomized Controlled Trial (RCT) design, we assessed the program's efficacy among 329 families in Starr, Zapata, and Hidalgo counties. Our findings reveal significant Intent-to-Treat effects on parental engagement and competencies in Hidalgo, suggesting the PCEP's effectiveness in improving parent-child interactions, parenting skills, and family involvement
Behavioral and Neural Correlates of Emotional Memory in Retirement and Late Life Neuropsychiatric Conditions
No full textThere is significant heterogeneity in aging, such that some older adults may experience significant memory decline while others remain relatively spared. This variability may be driven by a variety of individual differences. Here, we focus on two such differences: retirement and mental health. Retired older adults show greater memory decline relative to their working peers. However, retirement has been largely ignored in aging research. Furthermore, there are individual differences in retirement, such as levels of stress and mental health symptoms. Depression and anxiety are common in late life and are associated with cognitive decline and neurobiological dysfunction. However, it is unclear how comorbid depression and anxiety symptoms influence emotional memory and its neurobiological underpinnings in late life and retirement. We investigated these individual differences through a pattern separation framework. Hippocampal pattern separation is a neural computation that reduces interference across similar experiences and is sensitive to early impairment in aging and mood disorders. We used an emotional memory task that taxes hippocampal pattern separation to investigate how retirement and neuropsychiatric symptoms in aging were associated with memory and neurobiological function. Our first set of studies focused on the cognitive and neurobiological mechanisms of retirement. We found a positivity bias in memory (i.e., better memory for positive vs. neutral stimuli), a phenomenon commonly reported as a general trend in aging, was selective to retired rather than working older adults. Using high-resolution neuroimaging, we found that retired older adults exhibited dysfunctional hippocampal activity and connectivity, particularly for positive and neutral stimuli. The next set of studies assessed how neuropsychiatric symptoms impact these relationships, in which we found that retired older adults with subclinical depressive symptoms showed worse memory for positive stimuli, while those with high levels of prior job stress had a stronger positivity bias. When including a wider range of symptom severity, working older adults with more severe symptoms showed worse memory and greater hippocampal hyperactivity. Finally, we found that clusters of comorbid mental health symptoms were associated with unique patterns of neurobiological dysfunction. Overall, these studies provide novel insight into how individual differences in aging impact cognition and brain function
Tuning the properties of de novo living materials through genetic and environmental modifications
No full textEngineered living materials (ELMs) mimic the key characteristics of natural materials and are tailored to have enhanced non-natural functionalities. They contain cells that provide biological function and secrete an extracellular protein matrix that aids in their self-assembly and self-organization into multi-scale structures. Not only is the protein matrix essential in maintaining the structure of the living material, it enables the ability to tailor the bulk material properties for specific applications. However, few studies have focused on tuning the material properties of ELMs because this is a complex task that requires modulating the assembly of extracellular molecules. To address this knowledge gap, I explored how genetic and environmental modifications tune the bulk material properties using the bottom-up de novo engineered living materials (BUD-ELMs) platform in Caulobacter crescentus. First, I elucidated sequence-structure-property relationships in BUD-ELMs by changing the elastin-like polypeptide length within the extracellular protein matrix. I found fine-tuning genetic sequences in the protein matrix created significant differences in the microstructure and rheological properties of BUD-ELMs, revealing new design principles for creating living materials with tailored properties. Second, leveraging that the protein matrix contains exopolysaccharides (EPS), I evaluated how modifying the EPS and protein composition would tune the material properties using environmental modifications. I discovered that growing the BUD-ELM strain in sugar-based media formed de novo rope-like living materials that are strong and stiff with properties similar to elastomer and polymer-based materials. Lastly, I investigated how modulating the attachment of the protein matrix to the cells impacted the materials' properties by varying calcium concentrations in the growth conditions. I identified that microstructures with greater cell-matrix segregation led to bulk materials that are weaker, highlighting a simple strategy to significantly alter mechanical properties. Altogether, this thesis establishes a foundational framework for exploring structure-property relationships in ELMs to ultimately achieve rational material design and illuminates the transformative potential of de novo living materials in different applications, such as tissue engineering and drug delivery
Parameter Estimation of Neuron Models using Subset Selection and Dynamic Optimization
Get PDFThis thesis presents two frameworks for parameter estimation in neuron models and assesses parameter accuracy by constructing confidence regions of parameter estimates.
Parameter estimation helps advance the understanding of how neurons process sensory information. Nonlinear least squares have previously been used to fit biophysical neuron models. Yet, little attention has been devoted to handling rank-deficient problems, and to identifying and characterizing possible degeneracy in model parameters. To identify parameter degeneracy and resolve the rank deficiency, an SVD-based subset selection algorithm is used. Additional biophysical experiments are constructed, which constrain the least identifiable parameters. The approach is applied to the HCN neuron model. Moreover, an all-at-once optimization approach is applied, which includes the neuron model as a constraint and views parameters and model solution as optimization variables. This approach is demonstrated on the Pinsky-Rinzel model. The framework is designed to support the goal of applying them to complex compartmental neuron models