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Cerebral small-vessel damage manifests as white matter hyperintensities and cerebral atrophy on brain MRI and is associated with aging, cognitive decline and dementia. We sought to examine the interrelationship of these imaging biomarkers and the influence of hypertension in older individuals. We used a multivariate spatial covariance neuroimaging technique to

Cerebral small-vessel damage manifests as white matter hyperintensities and cerebral atrophy on brain MRI and is associated with aging, cognitive decline and dementia. We sought to examine the interrelationship of these imaging biomarkers and the influence of hypertension in older individuals. We used a multivariate spatial covariance neuroimaging technique to localize the effects of white matter lesion load on regional gray matter volume and assessed the role of blood pressure control, age and education on this relationship. Using a case-control design matching for age, gender, and educational attainment we selected 64 participants with normal blood pressure, controlled hypertension or uncontrolled hypertension from the Northern Manhattan Study cohort. We applied gray matter voxel-based morphometry with the scaled subprofile model to (1) identify regional covariance patterns of gray matter volume differences associated with white matter lesion load, (2) compare this relationship across blood pressure groups, and (3) relate it to cognitive performance. In this group of participants aged 60–86 years, we identified a pattern of reduced gray matter volume associated with white matter lesion load in bilateral temporal-parietal regions with relative preservation of volume in the basal forebrain, thalami and cingulate cortex. This pattern was expressed most in the uncontrolled hypertension group and least in the normotensives, but was also more evident in older and more educated individuals. Expression of this pattern was associated with worse performance in executive function and memory. In summary, white matter lesions from small-vessel disease are associated with a regional pattern of gray matter atrophy that is mitigated by blood pressure control, exacerbated by aging, and associated with cognitive performance.

ContributorsKern, Kyle C. (Author) / Wright, Clinton B. (Author) / Bergfield, Kaitlin L. (Author) / Fitzhugh, Megan C. (Author) / Chen, Kewei (Author) / Moeller, James R. (Author) / Nabizadeh, Nooshin (Author) / Elkind, Mitchell S. V. (Author) / Sacco, Ralph L. (Author) / Stern, Yaakov (Author) / DeCarli, Charles S. (Author) / Alexander, Gene E. (Author) / Ira A. Fulton Schools of Engineering (Contributor)
Created2017-05-15
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Description

Load associated fatigue cracking is one of the major distress types occurring in flexible pavements. Flexural bending beam fatigue laboratory test has been used for several decades and is considered an integral part of the Superpave advanced characterization procedure. One of the most significant solutions to sustain the fatigue life

Load associated fatigue cracking is one of the major distress types occurring in flexible pavements. Flexural bending beam fatigue laboratory test has been used for several decades and is considered an integral part of the Superpave advanced characterization procedure. One of the most significant solutions to sustain the fatigue life for an asphaltic mixture is to add sustainable materials such as rubber or polymers to the asphalt mixture. A laboratory testing program was performed on three gap-graded mixtures: unmodified, Asphalt Rubber (AR) and polymer-modified. Strain controlled fatigue tests were conducted according to the AASHTO T321 procedure. The results from the beam fatigue tests indicated that the AR and polymer-modified gap graded mixtures would have much longer fatigue lives compared to the reference (unmodified) mixture. In addition, a mechanistic analysis using 3D-Move software coupled with a cost-effectiveness analysis study based on the fatigue performance on the three mixtures were performed. Overall, the analysis showed that the AR and polymer-modified asphalt mixtures exhibited significantly higher cost-effectiveness compared to unmodified HMA mixture. Although AR and polymer-modification increases the cost of the material, the analysis showed that they are more cost effective than the unmodified mixture.

ContributorsSouliman, Mena I. (Author) / Mamlouk, Michael (Author) / Eifert, Annie (Author) / Ira A. Fulton School of Engineering (Contributor)
Created2016-05-20
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Description

The principles of a new project management model have been tested for the past 20 years. This project management model utilizes expertise instead of the traditional management, direction, and control (MDC). This new project management model is a leadership-based model instead of a management model. The practice of the new

The principles of a new project management model have been tested for the past 20 years. This project management model utilizes expertise instead of the traditional management, direction, and control (MDC). This new project management model is a leadership-based model instead of a management model. The practice of the new model requires a change in paradigm and project management structure. Some of the practices of this new paradigm include minimizing the flow of information and communications to and from the project manager [including meetings, emails and documents], eliminating technical communications, reducing client management, direction, and control of the vendor, and the hiring of vendors or personnel to do specific tasks. A vendors is hired only after they have clearly shown that they know what they are doing by showing past performance on similar projects, that they clearly understand how to create transparency to minimize risk that they do not control, and that they can clearly outline their project plan using a detailed milestone schedule including time, cost, and tasks all communicated in the language of metrics.

ContributorsRivera, Alfredo (Author) / Kashiwagi, Dean (Author) / Ira A. Fulton School of Engineering (Contributor)
Created2016-05-20
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Description

For the past three decades, the Saudi construction industry (SCI) has exhibited poor performance. Many research efforts have tried to identify the problem and the potential causes but there have been few publications identifying ways to mitigate the problem and describing testing to validate the proposed solution. This paper examines

For the past three decades, the Saudi construction industry (SCI) has exhibited poor performance. Many research efforts have tried to identify the problem and the potential causes but there have been few publications identifying ways to mitigate the problem and describing testing to validate the proposed solution. This paper examines the research and development (R&D) approach in the SCI. A literature research was performed identifying the impact that R&D has had on the SCI. A questionnaire was also created for surveying industry professionals and researchers. The results show evidence that the SCI practice and the academic research work exist in separate silos. This study recommends a change of mindset in both the public and private sector on their views on R&D since cooperation is required to create collaboration between the two sectors and improve the competitiveness of the country's economy.

ContributorsAlhammadi, Yasir (Author) / Algahtany, Mohammed (Author) / Kashiwagi, Dean (Author) / Sullivan, Kenneth (Author) / Kashiwagi, Jacob (Author) / Ira A. Fulton School of Engineering (Contributor)
Created2016-05-20
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Description

To date, little research has been performed regarding the planning and management of “small” projects – those projects typically differentiated from “large” projects due to having lower costs. In 2013, The Construction Industry Institute (CII) set out to develop a front end planning tool that will provide practitioners with a

To date, little research has been performed regarding the planning and management of “small” projects – those projects typically differentiated from “large” projects due to having lower costs. In 2013, The Construction Industry Institute (CII) set out to develop a front end planning tool that will provide practitioners with a standardized process for planning small projects in the industrial sector. The research team determined that data should be sought from industry regarding small industrial projects to ensure applicability, effectiveness and validity of the new tool. The team developed and administered a survey to determine (1) the prevalence of small projects, (2) the planning processes currently in use for small projects, and (3) current metrics used by industry to differentiate between small and large projects. The survey data showed that small projects make up a majority of projects completed in the industrial sector, planning of these projects varies greatly across the industry, and the metrics posed in the survey were mostly not appropriate for use in differentiating between small and large projects. This study contributes to knowledge through adding to the limited research surrounding small projects, and suggesting future research regarding using measures of project complexity to differentiate between small and large projects.

ContributorsCollins, Wesley (Author) / Parrish, Kristen (Author) / Gibson, G (Author) / Ira A. Fulton School of Engineering (Contributor)
Created2017-08-24
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Description

Pay-for-performance (PFP) is a relatively new approach to agricultural conservation that attaches an incentive payment to quantified reductions in nutrient runoff from a participating farm. Similar to a payment for ecosystem services approach, PFP lends itself to providing incentives for the most beneficial practices at the field level. To date,

Pay-for-performance (PFP) is a relatively new approach to agricultural conservation that attaches an incentive payment to quantified reductions in nutrient runoff from a participating farm. Similar to a payment for ecosystem services approach, PFP lends itself to providing incentives for the most beneficial practices at the field level. To date, PFP conservation in the U.S. has only been applied in small pilot programs. Because monitoring conservation performance for each field enrolled in a program would be cost-prohibitive, field-level modeling can provide cost-effective estimates of anticipated improvements in nutrient runoff. We developed a PFP system that uses a unique application of one of the leading agricultural models, the USDA's Soil and Water Assessment Tool, to evaluate the nutrient load reductions of potential farm practice changes based on field-level agronomic and management data. The initial phase of the project focused on simulating individual fields in the River Raisin watershed in southeastern Michigan. Here we present development of the modeling approach and results from the pilot year, 2015-2016. These results stress that (1) there is variability in practice effectiveness both within and between farms, and thus there is not one "best practice" for all farms, (2) conservation decisions are made most effectively at the scale of the farm field rather than the sub-watershed or watershed level, and (3) detailed, field-level management information is needed to accurately model and manage on-farm nutrient loadings.

ContributorsMuenich, Rebecca (Author) / Kalcic, M. M. (Author) / Winsten, J. (Author) / Fisher, K. (Author) / Day, M. (Author) / O'Neil, G. (Author) / Wang, Y.-C. (Author) / Scavia, D. (Author) / Ira A. Fulton School of Engineering (Contributor)
Created2017
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Description

Objective: To assess the informational, educational and instrumental environments among Mexican healthcare settings for their potential to promote physical activity (PA).

Materials and Methods: The Environmental Physical Activity Assessment Tool for Healthcare Settings (EPATHS) was developed to assess the PA environments of 40 clinics/hospitals representing the three Mexican healthcare systems in

Objective: To assess the informational, educational and instrumental environments among Mexican healthcare settings for their potential to promote physical activity (PA).

Materials and Methods: The Environmental Physical Activity Assessment Tool for Healthcare Settings (EPATHS) was developed to assess the PA environments of 40 clinics/hospitals representing the three Mexican healthcare systems in Guadalajara. The EPATHS assessed the presence and quality of PA enhancing features in the informational (e.g. signage),educational (e.g. pamphlets), and instrumental (e.g. stairs)environments of included clinics/hospitals.

Results: 28 (70%) clinics/hospitals had more than one floor with stairs; 60% of these had elevators. Nearly 90% of stairs were visible, accessible and clean compared to fewer than 30% of elevators. Outdoor spaces were observed in just over half (55%) of clinics/hospitals, and most (70%) were of good quality. Only 25% clinics/hospitals had educational PA materials.

Conclusions: The PA instrumental environment of Mexican healthcare settings is encouraging. The informational and educational environments could improve.

Created2015-09
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Description

Depression and anxiety after stroke negatively affect patient outcomes; however, health care professionals may overlook poststroke depression and anxiety while they focus on the physical disabilities of patients soon after a stroke. The purpose of this study was to investigate the prevalence and predictors of depression, anxiety, or both concurrently

Depression and anxiety after stroke negatively affect patient outcomes; however, health care professionals may overlook poststroke depression and anxiety while they focus on the physical disabilities of patients soon after a stroke. The purpose of this study was to investigate the prevalence and predictors of depression, anxiety, or both concurrently at one month after stroke. We conducted a cross-sectional, descriptive study in a sample of 231 hospitalized patients with ischemic stroke in Korea. Data were collected by interviews using a series of structured questionnaires in addition to clinical data retrieved from patients’ medical records. More than 70% were identified as depressed, 45.9% experienced anxiety, and 43.7% had concurrent depression and anxiety. Using a multiple logistic regression analysis, we identified anxiety as a predictor of depression; depression as a predictor of anxiety; and female sex, headaches, and swallowing difficulty as predictors of the comorbidity of depression and anxiety. Periodical screenings for poststroke depression and anxiety from an early stage in a hospital to years after stroke in a community are recommended to provide better chances for early identification of patients at risk because depression and anxiety may manifest at any stage of recovery. Special attention should be given to individuals with culture-bound somatic symptoms in addition to female patients and those who have difficulty swallowing among Korean stroke patients.

ContributorsShin, Cha-Nam (Author) / Sin, Mo-Kyung (Author) / Lee, Eunice (Author) / Lee, Jongwon (Author) / An, Kyungeh (Author) / Sim, Jeongha (Author) / Arizona State University. College of Nursing & Healthcare Innovation (Contributor)
Created2016
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Description

The utility of plasma amyloid beta (Aβ) and tau levels for the clinical diagnosis of Alzheimer’s disease (AD) dementia has been controversial. The main objective of this study was to compare Aβ42 and tau levels measured by the ultra-sensitive immunomagnetic reduction (IMR) assays in plasma samples collected at the Banner

The utility of plasma amyloid beta (Aβ) and tau levels for the clinical diagnosis of Alzheimer’s disease (AD) dementia has been controversial. The main objective of this study was to compare Aβ42 and tau levels measured by the ultra-sensitive immunomagnetic reduction (IMR) assays in plasma samples collected at the Banner Sun Health Institute (BSHRI) (United States) with those from the National Taiwan University Hospital (NTUH) (Taiwan). Significant increase in tau levels were detected in AD subjects from both cohorts, while Aβ42 levels were increased only in the NTUH cohort. A regression model incorporating age showed that tau levels identified probable ADs with 81 and 96% accuracy in the BSHRI and NTUH cohorts, respectively, while computed products of Aβ42 and tau increased the accuracy to 84% in the BSHRI cohorts. Using 382.68 (pg/ml)2 as the cut-off value, the product achieved 92% accuracy in identifying AD in the combined cohorts. Overall findings support that plasma Aβ42 and tau assayed by IMR technology can be used to assist in the clinical diagnosis of AD.

ContributorsLue, Lih-Fen (Author) / Sabbagh, Marwan N. (Author) / Chiu, Ming-Jang (Author) / Jing, Naomi (Author) / Snyder, Noelle L. (Author) / Schmitz, Christopher (Author) / Guerra, Andre (Author) / Belden, Christine M. (Author) / Chen, Ta-Fu (Author) / Yang, Che-Chuan (Author) / Yang, Shieh-Yueh (Author) / Walker, Douglas (Author) / Chen, Kewei (Author) / Reiman, Eric M. (Author) / Biodesign Institute (Contributor)
Created2017-07-24
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Description

Purpose: To identify barriers and discuss strategies for recruitment of older Chinese immigrants into clinical research studies.

Methods: A systematic review was conducted using Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA). PubMed, WEB of Science, CINAHL Plus, and the Cochrane Central Register of Controlled Trials were searched from 2001

Purpose: To identify barriers and discuss strategies for recruitment of older Chinese immigrants into clinical research studies.

Methods: A systematic review was conducted using Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA). PubMed, WEB of Science, CINAHL Plus, and the Cochrane Central Register of Controlled Trials were searched from 2001 to 2014. Empirical studies with Chinese immigrants aged 60 or older were identified and analyzed. Numerical analysis, such as calculation of response rates as indexes for recruitment outcomes, was conducted. Content analyses for recruitment barriers were abstracted.

Results: Thirteen studies of 4753 subjects were analyzed. Response rates ranged from 39% to 99%. Recruitment barriers include younger old age (i.e., 60-70 years old), low health literacy, longer length of stay in the US, limited English speaking ability, low acculturation, time constraints, inadequate transportation, social stigma about diseases, and mistrust of researchers.

Discussion: Recruitment can be facilitated by overcoming the aforementioned barriers, which include the following strategies: 1) using convenience sampling methods, particularly personal referral; 2) using special techniques to recruit younger subgroup of Chinese elders, such as doing outreach on holidays or weekends; 3) communicating effectively using participants’ native language; 4) exercising cultural competency; 5) establishing relationships of trust with participants and community leaders; 6) answering misconceptions about clinical trials; 7) providing incentives for participation; and 8) proper selection of research and interview locations.

Created2016