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DIETS AMONG FILIPINO SCHOOL-AGED CHILDREN: USUAL INTAKES, DIETARY INADEQUACY, AND THE DEVELOPMENT OF FOOD-BASED RECOMMENDATIONS
No full textBackground
Suboptimal dietary intake among school-aged children remains a major public health challenge in low- and middle-income countries, yet scarce data exist to inform interventions. While the Philippines conducts routine national nutrition surveys, limited analyses examine changes in dietary intake over time among school-aged children or develop evidence-based solutions for addressing dietary inadequacies.
Objectives
To characterize energy and nutrient usual intake, prevalence of inadequacies, and dietary changes over time and to develop food-based recommendations using locally available foods to meet dietary adequacy among school-aged children (5-10 years old) in the Philippines.
Methods
We conducted a secondary data analysis of the Philippines National Nutrition Survey (NNS) (2008, n=2749; 2013, n=2227), and, in 2022, we collected primary data from children as part of a nutritional assessment in two high-risk provinces for undernutrition (n=342). The National Cancer Institute (NCI) 1-day method was used to estimate usual intake and prevalence of inadequacy, using external variance ratios from the 2013 NNS. Linear regression models assessed changes in energy and nutrient intakes between 2008 and 2013. For the 2022 assessment, we analyzed 24-hour dietary recall data. The NCI 1-day method was used, with variance ratios from 2018 NNS, to estimate the usual intakes. Linear programming was then utilized to develop food-based recommendations using local foods while accounting for children’s realistic dietary practices.
Results
From 2008-2013, the intake of energy, protein, carbohydrates, and several micronutrients significantly decreased, while fat and vitamin A increased. High prevalence of inadequacy persisted for most nutrients, particularly calcium (85-98%), iron (50-65%) and vitamin C (40-64%). The 2022 assessment found a high prevalence of inadequacy across energy and nutrients. Linear programming analysis identified calcium as a problem nutrient for older children and found diets low in fruits, vegetables, and nutrient-dense foods. Food-based recommendations were set to improve dietary adequacy, which required increased consumption of anchovies, tuna, chicken liver, moringa, and vitamin C-rich fruits.
Conclusions
Filipino school-aged children experience persistent dietary inadequacies that could be addressed through carefully designed food-based recommendations incorporating local foods. Context-specific recommendations can inform school-based feeding programs and other interventions to improve dietary adequacy among this understudied age group
PROTEIN KINASE G STIMULATES CHAPERONE MEDIATED AUTOPHAGY IN CARDIOMYOCYTES
Get PDFCardiovascular diseases, including heart failure, remain the leading cause of death
worldwide. The progression of heart failure is exacerbated when the protein quality control (PQC) system becomes impaired and cannot efficiently remove misfolded or damaged proteins. The carboxyl terminus of Hsc70-interacting protein (CHIP), a co-chaperone with E3 ubiquitin ligase activity, plays a central role in maintaining cardiac PQC. Through chaperone-mediated autophagy (CMA), the Hsc70/CHIP complex recognizes a KFERQ motif on substrate proteins, binds to them, and facilitates their translocation to the Lamp2A receptor on the lysosome. Notably, we observed that Lamp2A expression is downregulated in the myocardium of human heart failure cases with either reduced or preserved ejection fraction (HFrEF, HFpEF), suggesting impaired CMA and highlighting a potential therapeutic target for these patients. Previously, we discovered that protein kinase G (PKG)-mediated phosphorylation of CHIP at serine 19 provides cardioprotective effects under stress conditions. Based on this, we hypothesize that phosphorylation of CHIP enhances its localization to the lysosome and stimulates CMA, representing a novel regulatory mechanism of CMA in the heart with therapeutic potential.
In addition to its role in CMA, CHIP also functions in the ubiquitin-proteasome
system (UPS) by facilitating the transfer of ubiquitin to target proteins, marking them for degradation by the 26S proteasome. Transthyretin amyloid cardiomyopathy (ATTR-CM) is a disorder in which misfolded transthyretin (TTR) aggregates into insoluble fibrils in the heart, leading to heart failure if untreated. Proteolysis-targeting chimeras (PROTACs) are bivalent small molecules engineered to bring together an E3 ligase and a protein of interest (POI). We designed a CHIP-TTR PROTAC to enable CHIP to selectively target intracellular TTR for degradation via the UPS. Upon treating iPSC-derived cardiomyocytes with TTR and the PROTAC, we observed reduced TTR levels following the PROTAC treatment. Our study aims to investigate the mechanism of the CHIP-TTR PROTAC and its potential therapeutic effects
CHINA’S INFORMATION AND COMMUNICATION TECHNOLOGY (ICT) DEVELOPMENT ASSISTANCE IN AFRICA: UNCOVERING BEIJING’S TECHNOLOGICAL APPROACH TO THE CONTINENT
No full textSince the turn of the century, China has provided substantial information and communication technology (ICT) development assistance throughout the Global South. Beijing’s technological strategies, policies, and initiatives promote modernization, mutual benefit, and the capacity to bridge the digital divide, promising a new era of development. However, the absence of region-specific plans as well as the overall lack of transparency in project implementation, against the backdrop of the People’s Republic of China’s (PRC) proclamation to become the global leader in innovation within the domain, has fueled widespread skepticism. The ambiguity and ambition have prompted the international community—particularly the US, its allies, and even host nations—to question China’s true intentions and long-term objectives. This skepticism is most notable in Africa, as over a third of China’s total ICT development assistance has been poured into the continent, yet a technological strategy has not been conveyed or interpreted.
Utilizing AidData’s Global Chinese Development Finance Dataset, Version 3.0, containing 357 Chinese ICT development assistance projects in Africa, this thesis explores the research question: To what extent does Chinese ICT development assistance in Africa support the PRC’s grand strategy? Applying a descriptive inference approach – on a macro-level, evaluating the synchronization of assistance flow to PRC strategies, – a meso-level, identifying the primary actors within the execution process, – and a micro-level, surveying project concentration and types – exposes the PRC’s technological approach rests on three major pillars. Beijing funds assistance through a select group of PRC agencies, heavily relies on Chinese private sector implementation, and profoundly targets the physical infrastructure layer. The approach, although decentralized, presents broader implications that are strategically problematic for the US and its allies
Learning Based Sensorless Contact Detection for Haptic Feedback on the da Vinci Research Kit
Get PDFUnderstanding when surgical tools make contact with human tissue during teleoperated robotic-assisted minimally invasive surgery could be used to enable haptic feedback on the operator side during surgical procedures. However, this task can be challenging, since in order to directly register contact at the surgical tool end effectors, it would require not only sensors small enough to not disrupt movement and view during surgery, but also the materials of the sensors that interact with the tissue to be sterilizable, biocompatible, and cost-effective. The implementation of kinematics-based and vision-based neural networks for force estimation and contact detection is a promising approach for the generalization of enabling haptic feedback in surgical robot instruments, although more research is required for the robustness of such implementations in different surgical robotics and procedural situations. This research presents implementations of a few one-class kinematics-based neural networks, as well as a combination of vision-based and kinematics-based neural networks, as a potential method for detecting contact in teleoperated robotic-assisted minimally invasive surgical procedures. Using the Generation 1 da Vinci Research Kit (dVRK), joint space kinematics and endoscope image data were collected, which were then used to train several contact detection neural networks. Two key metrics were used to assess the performance of the models, which were the accuracy and real-time latency of the model predictions. From experimentation, it was found that the contact detection model using both kinematics and vision data had the highest performance accuracy, around 90\%, compared to models using only kinematics data, which were around 80\%. However, when comparing latency, the kinematics and vision-based model had higher latency compared to that of the kinematics-only model. Although the accuracy results seemed promising, more research would be required to further improve accuracy and latency, as in real surgical situations, both are crucial aspects
Integrating Tactile Sensing with Soft Robotics for Sensory Feedback in Upper-Limb Prosthesis
No full textThis research is motivated by the need for natural and bio-inspired prosthetic hands that integrate tactile sensing and compliant grasping, offering individuals with upper limb loss enhanced sensory feedback for activities of daily living. Current prosthetic technologies lack the combined dexterity, compliance, and sensory capabilities required to mimic the human hand effectively. By leveraging the inherent compliance, safety, and biomimicry potential of soft robotics, this work seeks to create transformative solutions for upper-limb prosthesis users. Soft robots provide safer and more dexterous handling of delicate objects, directly interface with human bodies, and reduce costs while improving human-robot interaction. Tactile sensing, proven critical for object manipulation, delivers sensory feedback to improve functionality in prosthetic applications.
This dissertation introduces two innovations: a hybrid robotic hand and a smart fingertip, both integrating tactile sensing and soft robotics. The hybrid robotic hand combines soft robotic joints with a rigid endoskeleton and multilayered neuromorphic tactile sensing inspired by human physiology. This biomimetic prosthetic enables compliant grasping of objects with varied surface textures, weights, and compliance, achieving 99.69% object differentiation accuracy and 98.38% texture discrimination accuracy. Controlled via electromyography (EMG), it offers individuals with upper-limb loss the ability to manipulate objects with precision and detect surface textures during daily tasks.
The second contribution, the Opti-Jam fingertip integrates granular jamming-based soft robotics with optical tactile sensing to achieve simultaneous sensing and grasping. This compliant fingertip manipulates small, delicate objects while reconstructing their 3D shapes with high accuracy. Using a photometric stereo imaging algorithm and a high-resolution camera, the Opti-Jam fingertip achieved 89% classification accuracy across 10 delicate objects, demonstrating its potential for tactile feedback in robotic and prosthetic applications.
These innovations redefine the boundaries of prosthetic design, providing safer, more dexterous, and sensory-enabled solutions. They hold promise for improving the quality of life for individuals with upper-limb loss and advancing robotic manipulation capabilities in challenging environments
On-demand hypoxic hydrogels to investigate angiogenesis
No full textThe lack of oxygen, or hypoxia, elicits a multitude of tissue responses depending on the severity and duration of the exposure. Chronic hypoxia, lasting for days or weeks, is common in diseases including cancer and cardiovascular disorders. On the other hand, localized cessation of blood supply can lead to acute hypoxia, which typically lasts for a few minutes to a few hours. Our understanding of the threats caused by acute (i.e., short-term) hypoxia is limited mainly due to its transient nature and the lack of appropriate in vitro models to recapitulate its effect. Endothelial cells lining the inner blood vessels are the first to encounter changes in oxygen levels, including acute hypoxia.
In this work, we developed two hydrogel platforms that initially facilitate the formation of three- dimensional vascular sprouts and microvasculature, and then expose the three-dimensional constructs to controllable, acute hypoxia. The first hydrogel system consists of a gelatin-dextran backbone, which allows the generation of three-dimensional endothelial sprouts from spheroids and then introduces short-term moderate hypoxia “on demand”. Using the gelatin-dextran platform, we showed that moderate acute hypoxia (oxygen ~5%) leads to increased endothelial cell migration and sprouting from the established sprouts. Our findings indicate that the enhanced angiogenic response is regulated by reactive oxygen species, independently of hypoxia-inducible factors. Reactive oxygen species-dependent matrix metalloproteinase activity mediates the angiogenic sprouting that is observed following acute hypoxia.
In the subsequent work, we developed a fibrillar hydrogel based on collagen and hyaluronic acid, which enables the formation of three-dimensional microvascular tissue and then introduces severe acute hypoxia (oxygen ~1%) in the tissue microenvironment. Following reoxygenation, we observed increased angiogenesis from the established microvasculature. Time-lapse live-cell imaging of the three-dimensional vessels revealed increased mitochondrial fragmentation immediately following acute hypoxic exposure. We observed increased BNIP-3-mediated mitophagy in the “on demand” hypoxic hydrogels, which was subsequently confirmed by inhibition studies. Lastly, we examined changes in the proteome landscape of the three-dimensional vessels induced by acute hypoxia. Overall, we generated novel hydrogel platforms to study how “on-demand” acute hypoxia impacts angiogenesis, with broad applicability to developing novel sensing technologies
EXPLORATION OF GENE REGULATION IN B-1 CELL DEVELOPMENT, MAINTENANCE, AND FUNCTION
No full textB-1 cells are innate-like B cells that play a key role in natural antibody production, a first line of defense in immunity. However, the genes that selectively regulate their development, maintenance, and function remain to be more fully explored. This study is based on the search for genes inducing changes in B-1 cell frequencies in the spleens of 641 mouse strains, each harboring one known gene knockout, compared to their wild-type controls (about 200 mice) generated as part of the NIH-supported Knock Out Mouse Program and analyzing a total of 56 distinct cell populations using two multicolor flow cytometric panels. Seven mouse strains in which B-1 cell frequencies in the spleen were significantly and selectively altered were identified. Among these, mice lacking Ppp2r5a stood out as having shown significant reductions in spleen B-1 cells in both male and female mice. Ppp2r5a encodes a regulatory subunit of protein phosphatase 2A (PP2A), a regulator of cell growth and division. To confirm and expand these findings, for this thesis I retrieved mice lacking Ppp2r5a and conducted further flow cytometric analysis, which confirmed the selective B-1 cell deficiency in spleen and bone marrow in these mice. In addition, we observed significant decreases in serum IgM and IgG levels in PP2A-/- female but not in male mice. Thus, our work identifies Ppp2r5a as a gene necessary for normal B-1 cell self-renewal and their differentiation into antibody-secreting cells
The Making of Hyper-Flexible Employment in China and Its Rural Roots
No full textThis dissertation examines the rise of hyper-flexible employment among low-skilled and unskilled rural migrant workers in contemporary China, focusing on three interconnected spheres: the labor market, the workplace, and labor reproduction. It investigates the social relations, practices, and shared values that shape the experiences of rural migrant workers.
The dissertation highlights the labor brokerage industry as a key institutional infrastructure enabling hyper-flexible employment. Over the past decade, a nationwide network of labor brokers has been established, operating across industrial zones, rural areas, and vocational schools to facilitate rapid workforce recruitment during peak production periods. Within this context, the study identifies two distinct labor regimes in China’s electronics industry. While these regimes are not entirely despotic - workers retain some ability to leave when dissatisfied - they fall short of hegemonic arrangements. Workers remain subordinated to capital during production and disadvantaged in the labor market.
The dissertation also underscores the role of the rural economy in sustaining hyper-flexible employment. Aspirations for rural entrepreneurship continue to draw workers away from wage labor. However, when these entrepreneurial efforts fail, workers are often forced to return to wage labor, perpetuating the cycle of waged employment. The study also examines the significant challenges faced by rural entrepreneurship, which, despite some successes, struggles to provide viable alternatives to industrial employment.
Finally, the dissertation contributes to nonlinear theories of working-class formation by highlighting the diverse pathways shaping the experiences of rural migrant workers. And it challenges the traditional assumption that the formalization of labor is the normal or inevitable outcome of industrialization and modernization
Affordable Plasmonic Biosensing: Democratizing SERS with scalable, field-compatible substrate fabrication
Get PDFDespite the promise of surface-enhanced Raman spectroscopy (SERS) for point-of-care (PoC) diagnostics, its widespread adoption in field settings remains constrained by high production costs, complex fabrication methods, reliance on specialized equipment, and persistent issues with sensor stability and reproducibility. This thesis, based on the journal article with the same name “Affordable Plasmonic Biosensing: Democratizing SERS with Scalable, Field-Compatible Substrate Fabrication,” tackles these challenges by introducing a dendritic silver nanostructured surface fabrication kit. By leveraging simple battery-powered electrochemistry, this method eliminates dependence on the power grid. It also uses commonly available equipment, household and food-grade chemicals and bottled water. Instead of large scale foundries, these innovations enable the substrates to be made locally, even in resource-restricted and conflict-affected regions.
At the core of this innovation is a cost-effective approach: the entire fabrication kit can be assembled for $39.54 using bulk retail raw materials, while consumables required for each test cost only 1.33¢. To ensure real-world feasibility, we conducted extensive reproducibility analyses, confirming consistent intra-chip, inter-chip and intra-batch plasmonic. The platform’s performance is further validated by multiplexed detection of trace-level pesticides such as Thiram and Thiabendazole down to 0.1 ppm using digital SERS, as well as rapid, label-free identification of bacteria (Escherichia coli and Bacillus subtilis), highlighting key spectral features for high-accuracy decision making.
In addition to lowering substrate costs, the high signal-to-noise ratios afforded by SERS reduce the technical requirements for a Raman spectrometer, potentially cutting instrument costs. Moreover, because the system is label-free, spectrometers can be updated remotely for emerging pathogens, making this solution especially valuable for resource-restricted and conflict-affected regions. Ultimately, this work paves the way for a new era of accessible, high-performance SERS-based testing, fostering self-reliance in underserved communities and driving progress in public health, food safety, and beyond
DISCOVERING CELL TYPE-SPECIFIC MECHANISMS OF PATHOGENESIS IN CHARCOT-MARIE-TOOTH TYPE 4B3
No full textCharcot-Marie-Tooth type 4B3 (CMT4B3) is a severe, incurable peripheral neuropathy with autosomal recessive inheritance characterized by weakness, sensory loss, foot deformities, and muscle wasting. It involves peripheral neurodegeneration, which can be axonal or dysmyelinating. CMT4B3 results from loss-of-function mutations in SBF1, which encodes myotubularin-related phosphatase 5 (MTMR5), a neuron-enriched suppressor of the autophagy pathway that facilitates membrane phosphoinositide turnover, critical for autophagy induction and lysosomal function. Mouse models null for SBF1/MTMR5 demonstrate male infertility and axon hypomyelination, and do not exhibit other clinical and histopathological features observed in humans, highlighting the incomplete recapitulation of CMT4B3 in mice. With limited established cellular models or definitive mechanistic studies, understanding the diverse clinical phenotypes, primarily in the nervous system, is limited. To address this, we developed a novel patient-derived induced pluripotent stem cell (iPSC) model of CMT4B3 capable of differentiating into key peripheral nervous system (PNS) cell types, including isogenic motor neurons, sensory neurons, and skeletal muscle. This enabled the investigation of disease phenotypes in a cell-type–specific context. Since the role of autophagy in CMT4B3 pathogenesis had not been previously established, we sought to explore whether dysregulated autophagy contributes to disease pathology. To assess autophagic flux, we performed western blotting of autophagy substrates LC3B and p62. In parallel, we employed shRNA-mediated knockdown of SBF1 in isogenic motor neurons and skeletal muscle lines expressing the fluorescent autophagy reporter mEGFP-LC3B, enabling real-time visualization of autophagic dynamics via live-cell super-resolution microscopy. Our results revealed that loss of MTMR5 leads to increased autophagic activity across all cell types, with distinct phenotypic consequences depending on the lineage. These findings suggest that disrupted autophagy may contribute to the pathogenesis of CMT4B3 and underscore the importance of cell-type–specific approaches to understanding disease mechanisms and developing targeted therapeutic strategie