Dissertation: Examining and investigating home modifications and smart home technologies to reduce fall injury among older adults.

Nearly one in six U.S. residents are over the age of 65. The proportion of older adults in the U.S. is anticipated to grow to 22.1% of the total population by 2050. The cost of treating age related conditions and injuries is expensive, government programs including Medicaid paid over $550 Billion in 2017, and makes up between 14-16% of the federal budget each year. With the high cost of treating age related conditions and injuries, and the proportion of older adults continuing to increase every year, it is imperative that researchers and government entities find and invest in preventative measures in order to reduce injury and related healthcare costs. Among the many age-related injuries older adults suffer, falls are arguably the most important to address. It is estimated that one in three older adults has a fall every year. In 2016, falls were the seventh leading cause of death among older adults. Approximately one third of all fallers require medical attention after experiencing a fall. Over 800,000 older adults are hospitalized each year due to fall related injuries. Injuries sustained as a result of a serious fall include various fractures, traumatic brain injuries, and other cuts and bruises.Home modifications, and more recently smart home technologies, can help increase the safety of older adults living in the community. With older adults wanting to “age in place”, installing these modifications and technologies before an accident happens may lower rates of injury. Today, dozens of companies sell various smart home devices for the consumer market. Bud despite the high demand for these technologies by the American consumer, the ability of these devices to keep older adults safe, and how older adults value these technologies, remains uncertain. These home technologies may be particularly beneficial to older adults living in rural areas due to the increased isolation and limited access to healthcare resources. Previous research indicates rural populations have a greater proportion of older adults compared to urban areas, yet lack the infrastructure to provide specialty care to this population. It is estimated that more than 60 million family members provide some sort of informal care to an older adult relative. Of all of these family members, nearly 40% report spending 20 or more hours a week providing this unpaid care. Previous research has failed to examine how these family members feel about home modifications and technologies for their older adult relative. Finding ways to ease the burden of caring for older family members will significantly better the situations of many family relatives.This dissertation aims to cover three areas. 1. Identify people at risk of suffering subsequent fall injuries. Find the average time between an initial fall injury and a subsequent fall injury, and find average time between an initial fall injury and death.2. Examine the preferences of older adults living in a rural area towards various smart home technologies and home modifications.3. Examine the preferences of family members of older adults regarding smart home technologies and home modifications

Temporality in Phenomenology: Utilizing the Principles in Practice for Significance of a Sex Research

This article aims to demonstrate how the researcher can utilize the principle of temporality in phenomenology as a method to explore and to reveal the human experience through its application in sex research. Although phenomenological studies have been increasingly adopted for qualitative inquiry in the field of social science, the idea of the horizon of temporality and its practical utilization is rarely demonstrated explicitly. In this study, the researcher has investigated the interpretation of marital experience of Chinese spouses in Hong Kong who have been assessed with sexual dysfunctions with attention to the couples’ perspectives. Having adopted a synthetic qualitative research orientation in line with an interpretive research paradigm and with an emphasis on phenomenological principles, this article elicits the research paradigm, its philosophical orientation and the related research principles for a framework of utilizing temporality and its application for research

Chemical aspects related to using recycled geopolymers as aggregates

This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Despite extensive research into sustainability of geopolymers, end-of-life aspects have been largely overlooked. A recycling scenario is examined in this study. This requires an investigation of alkali leaching potential from a geopolymeric matrix. To study the feasibility of geopolymer cement (GPC) recycling, the migration of alkalis was evaluated for the first time on a microstructural level through energy dispersive X-ray (EDX) scanning electron microscopy (SEM) elemental mapping and leaching tests. Macroscale impacts were assessed through an investigation of Portland cement (PC) mortar properties affected by alkali concentration. Leaching tests indicated that alkalis immediately become available in aqueous environments, but the majority remain chemically or physically bound in the matrix. This type of leaching accelerates the initial setting of PC paste. Elemental mapping and EDX/SEM analysis showed a complex paste-aggregate interfacial transition zone. Exchange of calcium and sodium, revealed by the maps, resulted in the migration of sodium into the PC paste and the formation of additional calcium-silicon-based phases in the geopolymeric matrix. Strength values of mortars with 25% and 50% recycled aggregates (RA) showed negligible differences compared with the reference sample. Screening tests indicated a low potential for GPC RA inducing alkali-silica reaction. Transport of GPC RA alkalis and the underlying mechanisms were observed. This transport phenomenon was found to have minor effects on the properties of the PC mortar, indicating that recycling of geopolymers is a viable reuse practice.Peer reviewedFinal Published versio

Optimal trading strategy during bull and bear markets for Hong Kong-listed stocks

The “buy-and-hold” strategy based on the EMH was believed by many people to be optimal for a long time. However, there has been more criticism on the EMH since the global financial crisis in 2008. Hence many people attempt to find a trading strategy to beat “buy-and-hold”. Moreover, the financial market fluctuates a lot. Sometimes it is in a bull market, but it may be in a bear market during other periods of time, so the optimal strategy during different periods of time may vary and hence switching of strategies may be necessary. In this study, we apply Hui and Chan (2018)’s generalized time-dependent strategy on 12 Hong Kong listed stocks during the whole period of observation and two sub-periods. The results show that when the sub-period December 31, 2004–December 31, 2008 is chosen, the strategy outperforms “buy-and-hold” by the largest extent. This reflects that the strategy is most effective during adverse market conditions. This study can help investors to apply appropriate trading strategies to earn more profits, and help property practitioners to improve their strategic property management to increase the value of their portfolio

Cultural Norms Shaping Research Group Interviews with Chinese American Immigrants

Practical knowledge on how to tailor research methods for Asian Americans is relatively scarce despite the rapid population growth of this ethnic group and the ongoing calls for greater cultural competence among researchers. Based on a 4-year qualitative study of family and cultural issues in diabetes management among Chinese American immigrants, this article presents data-based analyses of culturally nuanced group interview processes, and recommendations for conducting culturally appropriate group interviews. Group interview processes were prominently shaped by 4 cultural norms: sensitivity to social hierarchy, monitoring public display of strong emotions, face concerns, and emphasis on group harmony. Strategies for facilitating open and dynamic group interviews in the presence of these norms were identified. Skillful facilitation of group processes, either by accommodating or diffusing norms, was required to promote participant rapport and encourage disclosure of everyday experience

Dual-Functional-Tag-Facilitated Protein Labeling and Immobilization

An important strategy in the construction of biomimetic membranes and devices is to use natural proteins as the functional components for incorporation in a polymeric or nanocomposite matrix. Toward this goal, an important step is to immobilize proteins with high efficiency and precision without disrupting the protein function. Here, we developed a dual-functional tag containing histidine and the non-natural amino acid azidohomoalanine (AHA). AHA is metabolically incorporated into the protein, taking advantage of the Met-tRNA and Met-tRNA synthetase. Histidine in the tag can facilitate metal-affinity purification, whereas AHA can react with an alkyne-functionalized probe or surface via well-established click chemistry. We tested the performance of the tag using two model proteins, green fluorescence protein and an enzyme pyrophosphatase. We found that the addition of the tag and the incorporation of AHA did not significantly impair the properties of these proteins, and the histidine–AHA tag can facilitate protein purification, immobilization, and labeling

Microscale controlled continuous cell culture

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2011.Cataloged from PDF version of thesis.Includes bibliographical references (p. 489-500).Measurements of metabolic and cellular activity through substrate and product interactions are highly dependent on environmental conditions and cellular metabolic state. For such experiments to be feasible, continuous cultures are utilized to ensure consistent conditions. However, since medium must be replenished every cell doubling time, costs can be prohibitive in large reactors. An integrated microscale bioreactor with built-in fluid metering and environmental control will enable programmed experiments capable of generating reproducible data routinely. This work develops an instrument capable of supporting automated microscale continuous culture experiments. The instrument consists of a plastic-PDMS device capable of continuous flow reactions without volume drift. A novel bonding process is invented to fabricate devices with chemically stable interfaces against water, acids, and bases. We introduce a direct CNC machining and chemical bonding fabrication process for production of fluidic devices with a 1 mL working volume, high oxygen transfer rate (kLa ~ 0.025 s-1), fast mixing (2 s), accurate flow control (± 18 nL), and closed loop control over temperature, cell density, oxygen, and pH. Providing control over environmental parameters allows the system to perform different types of cell culture on a single device, such as batch, fed-batch, chemostat, and turbidostat continuous culture. Validation experiments demonstrate that cells can be grown to high optical densities (OD = 50) and production of commercially relevant chemicals such as DNA vaccines are comparable to large scale bench fermentations. Continuous cultures are also demonstrated without contamination for 3 weeks in a single device and both steady state and dynamically controlled conditions are possible, allowing observations of cell metabolic dynamics.by Kevin Shao-Kwan Lee.Ph.D

Large core polymer optical backplanes for fluorescence detection

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2006.Includes bibliographical references (p. 203-205).Fluorescence based sensors are used for determining environmental parameters such as dissolved oxygen or pH in biological systems without disturbing a biological system's equilibrium. Recently, there has been a drive to provide biological analysis tools in a compact form, resulting in arrays of miniature devices which can perform multiple functions in parallel such as bacteria cultures or DNA analysis. As these new types of chips become more integrated and parallel, the amount of sensors required for them increases. As more sensors are added, off chip components such as photodetectors, LEDs, and fibers also begin to scale linearly. In an effort to simplify and integrate the detection side of these systems, a platform is being developed which utilizes the same polymer materials used for biochips to create optical components. By combining elements such as waveguides and mirror couplers, arrays of small devices capable of out-of-plane detection are possible, decoupling the biochip design from the transducer design while still maintaining compact integrated functionality.by Kevin Shao-Kwan Lee.S.M