Matching Items (157)
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Description

Background: Chemistry and particularly enzymology at surfaces is a topic of rapidly growing interest, both in terms of its role in biological systems and its application in biocatalysis. Existing protein immobilization approaches, including noncovalent or covalent attachments to solid supports, have difficulties in controlling protein orientation, reducing nonspecific absorption and preventing

Background: Chemistry and particularly enzymology at surfaces is a topic of rapidly growing interest, both in terms of its role in biological systems and its application in biocatalysis. Existing protein immobilization approaches, including noncovalent or covalent attachments to solid supports, have difficulties in controlling protein orientation, reducing nonspecific absorption and preventing protein denaturation. New strategies for enzyme immobilization are needed that allow the precise control over orientation and position and thereby provide optimized activity.

Methodology/Principal Findings: A method is presented for utilizing peptide ligands to immobilize enzymes on surfaces with improved enzyme activity and stability. The appropriate peptide ligands have been rapidly selected from high-density arrays and when desirable, the peptide sequences were further optimized by single-point variant screening to enhance both the affinity and activity of the bound enzyme. For proof of concept, the peptides that bound to β-galactosidase and optimized its activity were covalently attached to surfaces for the purpose of capturing target enzymes. Compared to conventional methods, enzymes immobilized on peptide-modified surfaces exhibited higher specific activity and stability, as well as controlled protein orientation.

Conclusions/Significance: A simple method for immobilizing enzymes through specific interactions with peptides anchored on surfaces has been developed. This approach will be applicable to the immobilization of a wide variety of enzymes on surfaces with optimized orientation, location and performance, and provides a potential mechanism for the patterned self-assembly of multiple enzymes on surfaces.

ContributorsFu, Jinglin (Author) / Reinhold, Jeremy (Author) / Woodbury, Neal (Author) / Biodesign Institute (Contributor)
Created2011-04-08
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Description

Maricopa County is the home of the Phoenix metropolitan area, an expansive city with serious air quality concerns. To ameliorate air quality in the county, the Maricopa County Air Quality Department developed a website and mobile application called "Clean Air Make More" as a means of outreach and engagement. In

Maricopa County is the home of the Phoenix metropolitan area, an expansive city with serious air quality concerns. To ameliorate air quality in the county, the Maricopa County Air Quality Department developed a website and mobile application called "Clean Air Make More" as a means of outreach and engagement. In doing this, the county has found a way to engender a bilateral relationship between individuals and their government agency. This study analyzes the effectiveness of Clean Air Make More in establishing this relationship and engaging the community in efforts to improve air quality. It concludes that the design of the application effectively meets user needs, but marketing efforts should target populations disposed to taking action regarding air quality.

ContributorsLapoint, Maggie Lane (Author) / Johnston, Erik W., 1977- (Thesis director) / Hondula, David M. (Committee member) / Barrett, The Honors College (Contributor) / W. P. Carey School of Business (Contributor) / School of International Letters and Cultures (Contributor)
Created2015-05
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Description

Background:
Environmental heat exposure is a public health concern. The impacts of environmental heat on mortality and morbidity at the population scale are well documented, but little is known about specific exposures that individuals experience.

Objectives:
The first objective of this work was to catalyze discussion of the role of personal heat exposure

Background:
Environmental heat exposure is a public health concern. The impacts of environmental heat on mortality and morbidity at the population scale are well documented, but little is known about specific exposures that individuals experience.

Objectives:
The first objective of this work was to catalyze discussion of the role of personal heat exposure information in research and risk assessment. The second objective was to provide guidance regarding the operationalization of personal heat exposure research methods.

Discussion:
We define personal heat exposure as realized contact between a person and an indoor or outdoor environment that poses a risk of increases in body core temperature and/or perceived discomfort. Personal heat exposure can be measured directly with wearable monitors or estimated indirectly through the combination of time–activity and meteorological data sets. Complementary information to understand individual-scale drivers of behavior, susceptibility, and health and comfort outcomes can be collected from additional monitors, surveys, interviews, ethnographic approaches, and additional social and health data sets. Personal exposure research can help reveal the extent of exposure misclassification that occurs when individual exposure to heat is estimated using ambient temperature measured at fixed sites and can provide insights for epidemiological risk assessment concerning extreme heat.

Conclusions:
Personal heat exposure research provides more valid and precise insights into how often people encounter heat conditions and when, where, to whom, and why these encounters occur. Published literature on personal heat exposure is limited to date, but existing studies point to opportunities to inform public health practice regarding extreme heat, particularly where fine-scale precision is needed to reduce health consequences of heat exposure.

ContributorsKuras, Evan R. (Author) / Richardson, Molly B. (Author) / Calkins, Mirian M. (Author) / Ebi, Kristie L. (Author) / Gohlke, Julia M. (Author) / Hess, Jeremy J. (Author) / Hondula, David M. (Author) / Kintziger, Kristina W. (Author) / Jagger, Meredith A. (Author) / Middel, Ariane (Author) / Scott, Anna A. (Author) / Spector, June T. (Contributor) / Uejio, Christopher K. (Author) / Vanos, Jennifer K. (Author) / Zaitchik, Benjamin F. (Author)
Created2017-08
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Description
Hyperspectral imaging is a novel technology which allows for the collection of reflectance spectra of a sample in-situ and at a distance. A rapidly developing technology, hyperspectral imaging has been of particular interest in the field of art characterization, authentication, and conservation as it avoids the pitfalls of traditional characterization

Hyperspectral imaging is a novel technology which allows for the collection of reflectance spectra of a sample in-situ and at a distance. A rapidly developing technology, hyperspectral imaging has been of particular interest in the field of art characterization, authentication, and conservation as it avoids the pitfalls of traditional characterization techniques and allows for the rapid and wide collection of data never before possible. It is hypothesized that by combining the power of hyperspectral imaging with machine learning, a new framework for the in-situ and automated characterization and authentication of artworks can be developed. This project, using the CMYK set of inks, began the preliminary development of such a framework. It was found that hyperspectral imaging and machine learning as a combination show significant potential as an avenue for art authentication, though further progress and research is needed to match the reliability of status quo techniques.
ContributorsChowdhury, Tanzil Aziz (Author) / Newman, Nathan (Thesis director) / Tongay, Sefaattin (Committee member) / School of Politics and Global Studies (Contributor) / Materials Science and Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
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Description
In June 2016, the Arizona Department of Health Services (ADHS) with researchers from Arizona State University (ASU) convened a one-day workshop of public health professionals and experts from Arizona’s county and state agencies to advance statewide preparedness for extreme weather events and climate change. The United States Centers for Disease

In June 2016, the Arizona Department of Health Services (ADHS) with researchers from Arizona State University (ASU) convened a one-day workshop of public health professionals and experts from Arizona’s county and state agencies to advance statewide preparedness for extreme weather events and climate change. The United States Centers for Disease Control and Prevention (CDC) sponsors the Climate-Ready Cities and States Initiative, which aims to help communities across the country prepare for and prevent projected disease burden associated with climate change. Arizona is one of 18 public health jurisdictions funded under this initiative. ADHS is deploying the CDC’s five-step Building Resilience Against Climate Effects (BRACE) framework to assist counties and local public health partners with becoming better prepared to face challenges associated with the impacts of climate-sensitive hazards. Workshop participants engaged in facilitated exercises designed to rigorously consider social vulnerability to hazards in Arizona and to prioritize intervention activities for extreme heat, wildfire, air pollution, and flooding.

This report summarizes the proceedings of the workshop focusing primarily on two sessions: the first related to social vulnerability mapping and the second related to the identification and prioritization of interventions necessary to address the impacts of climate-sensitive hazards.
ContributorsRoach, Matthew (Author) / Hondula, David M. (Author) / Putnam, Hana (Author) / Chhetri, Nalini (Author) / Chakalian, Paul (Author) / Watkins, Lance (Author) / Dufour, Brigette (Author)
Created2016-11-28
Description
This study examines the complex relationship between depression and students' experiences in active learning science courses. We uncover the significant impact of depression on cognitive functioning, particularly affecting energy levels, motivation, and self-doubt, especially among women. Highlighting the intersectionality of gender and depression, we stress the need to address disparities

This study examines the complex relationship between depression and students' experiences in active learning science courses. We uncover the significant impact of depression on cognitive functioning, particularly affecting energy levels, motivation, and self-doubt, especially among women. Highlighting the intersectionality of gender and depression, we stress the need to address disparities and bolster confidence in academic settings.
ContributorsClark, Sarah (Author) / Cooper, Katelyn (Thesis director) / Brownell, Sara (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor) / Dean, The College of Liberal Arts and Sciences (Contributor)
Created2024-05
Description
Transition metal dichalcogenides (TMDs) are a family of layered crystals with the chemical formula MX2 (M = W, Nb, Mo, Ta and X = S, Se, Te). These TMDs exhibit many fascinating optical and electronic properties making them strong candidates for high-end electronics, optoelectronic application, and spintronics. The layered structure

Transition metal dichalcogenides (TMDs) are a family of layered crystals with the chemical formula MX2 (M = W, Nb, Mo, Ta and X = S, Se, Te). These TMDs exhibit many fascinating optical and electronic properties making them strong candidates for high-end electronics, optoelectronic application, and spintronics. The layered structure of TMDs allows the crystal to be mechanically exfoliated to a monolayer limit, where bulk-scale properties no longer apply and quantum effects arise, including an indirect-to-direct bandgap transition. Controllably tuning the electronic properties of TMDs like WSe2 is therefore a highly attractive prospect achieved by substitutionally doping the metal atoms to enable n- and p-type doping at various concentrations, which can ultimately lead to more effective electronic devices due to increased charge carriers, faster transmission times and possibly new electronic and optical properties to be probed. WSe2 is expected to exhibit the largest spin splitting size and spin-orbit coupling, which leads to exciting potential applications in spintronics over its similar TMD counterparts, which can be controlled through electrical doping. Unfortunately, the well-established doping technique of ion implantation is unable to preserve the crystal quality leading to a major roadblock for the electronics applications of tungsten diselenide. Synthesizing WSe2 via chemical vapor transport (CVT) and flux method have been previously established, but controllable p-type (niobium) doping WSe2 in low concentrations ranges (<1 at %) by CVT methods requires further experimentation and study. This work studies the chemical vapor transport synthesis of doped-TMD W1-xNbxSe2 through characterization techniques of X-ray Diffraction, Scanning Electron Microscopy, Energy Dispersive X-ray Spectroscopy, and X-ray Photoelectron Spectroscopy techniques. In this work, it is observed that excess selenium transport does not enhance the controllability of niobium doping in WSe2, and that tellurium tetrachloride (TeCl4) transport has several barriers in successfully incorporating niobium into WSe2.
ContributorsRuddick, Hayley (Author) / Tongay, Sefaattin (Thesis director) / Jiao, Yang (Committee member) / Barrett, The Honors College (Contributor) / Materials Science and Engineering Program (Contributor)
Created2024-05