Nanotechnology-enabled immunoengineering approaches to advance therapeutic applications

Chuang Skylar T.,Conklin Brandon,Stein Joshua B.,Pan George,이기범 나노기술연구협의회 2022 Nano Convergence Vol.9 No.19

Immunotherapy has reached clinical success in the last decade, with the emergence of new and effective treatments such as checkpoint blockade therapy and CAR T-cell therapy that have drastically improved patient outcomes. Still, these therapies can be improved to limit off-target effects, mitigate systemic toxicities, and increase overall efficacies. Nanoscale engineering offers strategies that enable researchers to attain these goals through the manipulation of immune cell functions, such as enhancing immunity against cancers and pathogens, controlling the site of immune response, and promoting tolerance via the delivery of small molecule drugs or biologics. By tuning the properties of the nanomaterials, such as size, shape, charge, and surface chemistry, different types of immune cells can be targeted and engineered, such as dendritic cells for immunization, or T cells for promoting adaptive immunity. Researchers have come to better understand the critical role the immune system plays in the progression of pathologies besides cancer, and developing nanoengineering approaches that seek to harness the potential of immune cell activities can lead to favorable outcomes for the treatment of injuries and diseases.

Schoolchildren's antioxidation genotypes are susceptible factors for reduced lung function and airway inflammation caused by air pollution

Chen, B.Y.,Chen, C.H.,Chuang, Y.C.,Kim, H.,Honda, Y.,Chiang, H.C.,Guo, Y.L. Academic Press 2016 Environmental research Vol.149 No.-

Background: We recently reported the relationship between exposure to ambient air pollutants and changes in lung function and nasal inflammation among schoolchildren. A study was conducted to investigate whether antioxidation genotypes influence these associations. Methods: A follow-up study of 97 schoolchildren was conducted in New Taipei City, Taiwan. A structured respiratory health questionnaire was administered in September 2007, followed by monthly spirometry and measurement of nasal inflammation from October 2007 to November 2009. During the study period, complete daily monitoring data for air pollutants were obtained from the Environmental Protection Administration monitoring station and Aerosol Supersite. The genotypes of glutathione S-transferase (GST) subunits M1, T1, P1 and superoxide dismutases subunit 2 (SOD2) were characterized. Mixed-effects models were used, adjusting for known confounders. Result: GSTM1 null children had significant PM<SUB>2.5</SUB>-related increment in leukocyte (8.52%; 95% confidence interval (CI): 3.13-13.92%) and neutrophil (9.68%; 95% CI: 4.51-14.85%) in nasal lavage. Ozone levels were significantly and inversely associated with forced expiratory flow at 25% of forced vital capacity (FEF<SUB>25%</SUB>) (-0.43L/s; 95% CI: -0.58,-0.28L/s) in SOD2 Ala16 variant children. Conclusion: In this longitudinal study of schoolchildren. Our data provide evidence that antioxidation genotype modifies the airway inflammation caused by PM<SUB>2.5</SUB>. Antioxidation genotype also acts as an effect modifier, but not strong, in ozone-related small airway function response.

School and Community Partnerships in Emergent Democracies: Narratives and Evidence from the Philippines

Rohaiba B. Radiamoda,Hsueh-Hua Chuang,Ronald A. Pernia,Magnolia A. Laus 부경대학교 글로벌지역학연구소 2023 Journal of Global and Area Studies(JGA) Vol.7 No.2

School and community partnerships are considered effective for achieving educational reforms, yet this type of collaborative enterprise continues to suffer from a crisis of relevance and sustainability up to the present. Hence, this study aims to identify factors that hinder the actualization of school–community partnerships. Using a case study approach, we conducted key-informant interviews, focus group discussions, and field observations in a public school in Cebu, Philippines. Through a thematic analysis of the data and anchored on Epstein’s Theory of Overlapping Influence (OSI), the study found that school leadership, sense of reciprocity, dynamics of local politics, and parent’s self-efficacy are the key factors that affect the practice of effective school and community partnerships. We also highlight that distinctive school contexts dictate how such partnerships are organized. One interesting finding indicates that the “diffusion of responsibility” may be detrimental. With the implementation of school-based management, the subjective diffusion of responsibility to “many leaders” results to finger-pointing and less proactive behavior. The spirit of school and community partnerships is in proper communication and effective collaboration―a critical dimension of the OSI model; without it, its purest intentions are most likely to fail. In an ironic twist of fate, decentralization of education, which is supposed to decenter the responsibilities of localities and peripheries, may actually hurt (instead of help) substantive educational and public policies in emergent democracies.

The Manufacturing Process Effects on the Tensile and Creep Behavior of High Strength Polyester Yarns

W. Hsieh,B. Chuang,J. Liu 한국토목섬유학회 2011 한국지반신소재학회 학술발표회 Vol.2011 No.11

Pretension and heating are common processes in the production of flexible geogrids. The pretension and heating temperature effects on the tensile and creep behavior of two types of high strength polyester yarns were investigated. Two types of polyester yarns provided from different local manufactures were used. The unit weights of the test yarns are 2013 (Type A) and 1511 (Type B) dynes, respectively. The ultimate tensile strength of the test yarns are 8.8 g/dyne and 8.9 g/dyne, respectively. 20%, 30%, 50% UTS pretension forces and 150℃, 170℃ and 180℃ heating temperatures were used to simulate the manufacturing process. A series of tensile tests (ASTM D2256) and conventional longterm (ASTM D5262) creep tests were performed to evaluate the tensile strength, elongation at rupture and long-term creep strain of the test polyester yarns. Scanning Electronics Microscope (SEM) technique was also used to visual evaluation the surface structure of the yarns before and after the simulated manufacturing process and creep tests. The test results indicated that the ultimate tensile strength of the polyester yarns decreases bilinearly as the test temperature is increased. The bi-linear tensile strength decrease rate is about -0.37 N and -0.74 N per degree of Celsius, respectively for Type A polyester yarn. The elongation at break for the tested yarns varied from 10.57% to 12.49% for test temperature varying from 20℃ to 80℃, respectively. The tensile strength and elongation at break at around 70℃ test condition was inconsistent with the results from other test conditions. It is believed that the glass formation phenomenon might have some effects on the engineering behavior of the tested yarns at a temperature around 70℃. Drying the polymer coating by heating would induce polyester yarn shrinkage during the geogrid production process. A minimum of 10% UTS pretension load is required to prevent shrinkage in the test polyester yarns. The single strand tensile test results for the processed polyester yarns indicated that the elongation at break was reduced by 1.5% to 2.0%. Linear creep strain curves on a semi-log scale diagram were observed from a series of 1000-hour conventional long-term creep tests for polyester yarns processed at different temperatures. The curve slope decreased as the pretension load and heating temperature were increased. The creep strain rates decrease very rapidly at the initial stage and reach a plateau stage after 50 hours loading during the tests. Secondary creep behavior was observed for the control and processed 1000-hour creep tests. The creep strain rate decreases as the pretension load and heating temperature were increased. Hair cracks were observed from SEM pictures for the samples obtained from a simulated manufacturing process after 1000-hours conventional creep testing. Similar test results were observed for both tested polyester yarns.

Thickness Dependent Reactivity with Oxygen for Ultrathin Co/Si(111) Films

C.H. Chuang,W.Y. Chang,J.S. Tsay,H.W. Chang,W. B. Su,Y.D. Yao 한국자기학회 2010 한국자기학회 학술연구발표회 논문개요집 Vol.2010 No.12

Asymmetric saccade reaction times to smooth pursuit

Bieg, Hans-Joachim,Chuang, Lewis L.,Bü,lthoff, Heinrich H.,Bresciani, Jean-Pierre Springer Berlin Heidelberg 2015 Experimental brain research Vol.233 No.9

<P>Before initiating a saccade to a moving target, the brain must take into account the target’s eccentricity as well as its movement direction and speed. We tested how the kinematic characteristics of the target influence the time course of this oculomotor response. Participants performed a step-ramp task in which the target object stepped from a central to an eccentric position and moved at constant velocity either to the fixation position (foveopetal) or further to the periphery (foveofugal). The step size and target speed were varied. Of particular interest were trials that exhibited an initial saccade prior to a smooth pursuit eye movement. Measured saccade reaction times were longer in the foveopetal than in the foveofugal condition. In the foveopetal (but not the foveofugal) condition, the occurrence of an initial saccade, its reaction time as well as the strength of the pre-saccadic pursuit response depended on both the target’s speed and the step size. A common explanation for these results may be found in the neural mechanisms that select between oculomotor response alternatives, i.e., a saccadic or smooth response.</P>

Haptic Feedback Cues Can Improve Human Perceptual Awareness in Multi-Robots Teleoperation

Hyoung Il Son,Lewis L. Chuang,Junsuk Kim,Heinrich H. B¨ulthoff 제어로봇시스템학회 2011 제어로봇시스템학회 국제학술대회 논문집 Vol.2011 No.10

The availability of additional force cues in haptic devices are often expected to improve control performance, over conditions that only provide visual feedback. However, there is little empirical evidence to show this to be true for the teleoperation control of remote vehicles (i.e., multiple unmanned aerial vehicles (UAVs)). In this paper, we show that force cues can increase one’s sensitivity in discerning the presence of obstacles in the remote multi-UAVs’ environment. Significant benefits, relative to a purely visual scenario, were achieved only when force cues were sufficiently amplified by large gains. In addition, force cues tended to provide stronger benefits when they were based on the UAVs’ velocity information.

Development of a Dynamic System Simulating Pig Gastric Digestion

Chiang, C.-C.,Croom, J.,Chuang, S.-T.,Chiou, P.W.S.,Yu, B. Asian Australasian Association of Animal Productio 2008 Animal Bioscience Vol.21 No.10

The objective of this study was to develop a model for simulating gastric digestion in the pig. The model was constructed to include the chemical and physical changes associated with gastric digestion such as enzyme release, digestion product removal and gastric emptying. Digesta was collected from the stomach cannula of pigs to establish system parameters and to document the ability of the model to simulate gastric digestion. The results showed that the average pH of gastric digesta increased significantly from 2.47 to 4.97 after feed consumption and then decreased 140 min postprandial. The model described the decrease in pH within the pigs' stomach as $pH_t=5.182e^{-0.0014t}$, where t represents the postprandial time in minutes. The cumulative distribution function of liquid digesta was $V_t=64.509e^{0.0109t}$. The average pepsin activity in the liquid digesta was 317Anson units/mL. There was significant gastric emptying 220 min after feed consumption. The cybernetic dynamic system of gastric digestion was set according to the above data in order to compare with in vivo changes. The time course of crude protein digestion predicted by the model was highly correlated with observed in vivo digestion (r = 0.97; p = 0.0001), Model prediction for protein digestion was higher than that observed for a traditional static in vitro method (r = 0.89; p = 0.0001).

Rewiring of Genetic Networks in Response to DNA Damage

Bandyopadhyay, S.,Mehta, M.,Kuo, D.,Sung, M.-K.,Chuang, R.,Jaehnig, E. J.,Bodenmiller, B.,Licon, K.,Copeland, W.,Shales, M.,Fiedler, D.,Dutkowski, J.,Guenole, A.,van Attikum, H.,Shokat, K. M.,Kolodner American Association for the Advancement of Scienc 2010 Science Vol.330 No.6009

<P>Although cellular behaviors are dynamic, the networks that govern these behaviors have been mapped primarily as static snapshots. Using an approach called differential epistasis mapping, we have discovered widespread changes in genetic interaction among yeast kinases, phosphatases, and transcription factors as the cell responds to DNA damage. Differential interactions uncover many gene functions that go undetected in static conditions. They are very effective at identifying DNA repair pathways, highlighting new damage-dependent roles for the Slt2 kinase, Pph3 phosphatase, and histone variant Htz1. The data also reveal that protein complexes are generally stable in response to perturbation, but the functional relations between these complexes are substantially reorganized. Differential networks chart a new type of genetic landscape that is invaluable for mapping cellular responses to stimuli.</P>