Brian Chu, Professor of Art travels to Taiwan and China

Assistance from the CIE Major Grant helped me travel to Taiwan and China in summer 2015. In this 70-day trip I satisfied my three goals of research, teaching, and international education program development

Stepping Responses to Treadmill Perturbations vary with Severity of Motor Deficits in Human SCI

In this study, we investigated the responses to tread perturbations during human stepping on a treadmill. Our approach was to test the effects of perturbations to a single leg using a split-belt treadmill in healthy participants and in participants with varying severity of spinal cord injury (SCI). We recruited 11 people with incomplete SCI and 5 noninjured participants. As participants walked on an instrumented treadmill, the belt on one side was stopped or accelerated briefly during mid to late stance. A majority of participants initiated an unnecessary swing when the treadmill was stopped in mid stance, although the likelihood of initiating a step was decreased in participants with more severe SCI. Accelerating or decelerating one belt of the treadmill during stance altered the characteristics of swing. We observed delayed swing initiation when the belt was decelerated (i.e. the hip was in a more flexed position at time of swing) and advanced swing initiation with acceleration (i.e. hip extended at swing initiation). Further, the timing and leg posture of heel strike appeared to remain constant, reflected by a sagittal plane hip angle at heel strike that remained the same regardless of the perturbation. In summary, our results supported the current understanding of the role of sensory feedback and central drive in the control of stepping in participants with incomplete SCI and noninjured participants. In particular, the observation of unnecessary swing during a stop perturbation highlights the interdependence of central and sensory drive in walking control

Perception of Lower Extremity Loads in Stroke Survivors

Objective: This study aimed to improve our understanding of static and dynamic lower extremity sensory perception and the impact of sensory impairments on the control of walking in stroke survivors. Methods: Using a custom, real-time unloading system, we tested load perception at heel strike, mid stance and push off in 10 stroke survivors and compared their performance to 10 age-matched and 5 young adult control subjects. Dynamic load perception was based on a judgment of which leg was bearing more load, which was altered on a step by step basis. We also examined lower extremity static load perception, coordination, proprioception, balance, and gait symmetry. Results: The stroke survivors performed significantly worse than the control subjects in dynamic load perception, coordination, proprioception, balance and gait symmetry. Gait symmetry correlated with static and dynamic load perception measures but not with age, proprioception, coordination, and balance. Conclusions: Sensory deficits related to load detection in the impaired limb could result in an increased uncertainty of limb load and a gait strategy in which stroke survivors minimize loading of the impaired limb. Significance: This new method of measuring lower extremity dynamic load perception provides a framework for understanding gait-related sensory impairments in stroke survivors

Feasibility of Concurrent Treatment of Arsenic and Molybdenum through Co-Precipitation and Adsorption with Case Study and Cost Analysis

Feasibility of Concurrent Treatment of Arsenic and Molybdenum through Co-Precipitation and Adsorption with Case Study and Cost Analysis Authors Mrs. Prachi Jain - United States - Haley & Aldrich, Inc. Mr. Brian Colonnese - United States - Haley & Aldrich, Inc. Dr. Jacob Chu - United States - Haley & Aldrich Inc. Abstract Molybdenum and arsenic are among the Appendix IV constituents required to be monitored under the coal combustion residuals (CCR) Rule. At some CCR sites, arsenic and molybdenum in CCR-impacted groundwater were found concurrently at a level above their groundwater protection standards. In the environment, molybdenum is highly soluble in water, usually present in the form of an oxyanion, and relatively weak in terms of sorption onto geological media with a low organic content. In contrast, while arsenic is also typically soluble and present in the form of oxyanions in groundwater, arsenic generally has a higher tendency to be adsorbed onto geological media in comparison to molybdenum. Therefore, arsenic transport in groundwater is typically slower than molybdenum. In pursuit of the most efficient and effective groundwater remedies for CCR sites, ideally remedies can concurrently treat multiple site-specific CCR constituents that exceed the groundwater protection standards. In this presentation, we will present review site-specific treatability test data where molybdenum and arsenic are the primary constituents of concern in groundwater. The treatability studies were designed to investigate the effects of ferric iron in aerobic conditions and the ability to promote co-precipitation and adsorption removal of arsenic and molybdenum concurrently to the levels below their respective groundwater protection standards (10 µg/L for arsenic and 100 µg/L for molybdenum). Preliminary laboratory treatability testing results indicate that the concurrent treatment can be achieved at a pH range between 5 and 5.5, with a ferric iron dose higher than 30 mg/L. In this same context, the results of preliminary remedial cost assessments will be presented for an ex-situ treatment system case study that utilizes optimal conditions with ferric iron enhancements to remove molybdenum and arsenic at three different treatment capacities (30 gallons per minute [gpm], 100 gpm, and 500 gpm)

Rendering the Social in the Architectural Scene: Digital Representation and Social Inclusion on Architectural Design, Thinking, and Education

The digital production of hyper-rendered scenes has come to dominate architectural practice. Jean Baudrillard's warning that simulation will replace the real is now obvious and ubiquitous in our wirelessly networked mediated lives. CAD monkeys, rendering farms, and out-sourcers form the cabal behind the global production of seductive computer generated imagery detached from real people and places. This paper builds on the premise that physical places, designed and marketed through digital imagery, set the stage for the "social scenes" of tourism, leisure and consumption, and that privatized public spaces become "images" in themselves. Providing a setting for ways of people seeing, and being seen by others, these images encourage us to mimic the poses and gestures of architectural renderings. Standing against our growing obsession with rendered architectural scenes suggests that, as digital modes of creation and representation increasingly become objectives in and of themselves, architectural practice is prone to blindness in the face of social developments which exist independently of architecture's digital turn. The paper highlights the possible integration of the social and the technological through documenting a series of design, professional, and pedagogical projects which have, during the thirty-year period of architecture's 'digital turn', increasingly incorporated 'the digital', but which have persistently continued to foreground the social

Molecular computations for reactions and phase transitions: applications to protein stabilization, hydrates and catalysis

In this work we have made significant contributions in three different areas of interest: therapeutic protein stabilization, thermodynamics of natural gas clathrate-hydrates, and zeolite catalysis. In all three fields, using our various computational techniques, we have been able to elucidate phenomena that are difficult or impossible to explain experimentally. More specifically, in mixed solvent systems for proteins we developed a statistical-mechanical method to model the thermodynamic effects of additives in molecular-level detail. It was the first method demonstrated to have truly predictive (no adjustable parameters) capability for real protein systems. We also describe a novel mechanism that slows protein association reactions, called the “gap effect.” We developed a comprehensive picture of methioine oxidation by hydrogen peroxide that allows for accurate prediction of protein oxidation and provides a rationale for developing strategies to control oxidation. The method of solvent accessible area (SAA) was shown not to correlate well with oxidation rates. A new property, averaged two-shell water coordination number (2SWCN) was identified and shown to correlate well with oxidation rates. Reference parameters for the van der Waals Platteeuw model of clathrate-hydrates were found for structure I and structure II. These reference parameters are independent of the potential form (unlike the commonly used parameters) and have been validated by calculating phase behavior and structural transitions for mixed hydrate systems. These calculations are validated with experimental data for both structures and for systems that undergo transitions from one structure to another. This is the first method of calculating hydrate thermodynamics to demonstrate predictive capability for phase equilibria, structural changes, and occupancy in pure and mixed hydrate systems. We have computed a new mechanism for the methanol coupling reaction to form ethanol and water in the zeolite chabazite. The mechanism at 400°C proceeds via stable intermediates of water, methane, and protonated formaldehyde.Singapore-MIT Alliance (SMA