Time filter

Source Type

Alondra Park, CA, United States

Russ-Eft D.,Formerly American Institutes for Research | Burling A.,Oregon State University | Stephens J.,American Institutes for Research | Downey J.,Cerritos College
Evaluation and Program Planning | Year: 2013

Evaluation of research capacity building programs presents challenges, including defining " research capacity building" and measuring it. The present study evaluates infrastructure capacity-building strategies and barriers and facilitators of two federally funded health-related research capacity building programs within the United States. We developed a conceptual framework and abstracted 223 data elements from existing project files. We administered questionnaires to 17 principal investigators and conducted 2-h interviews of 15 principal investigators. Finally, we conducted one-and-a-half-day site visits with five projects. We aggregated data and analysis results across the two programs. Impacts and strategies were also analyzed as to whether host institutions had little or no existing research infrastructure (" seed projects" ) or had well-developed research infrastructure (" fertilizer projects" ). Projects were associated with increases in publication and presentation rates by Principal Investigators and staff, increases in research funding, changes in organizational research culture, and positive impacts on the community. Project characteristics and activities associated with each of these outcomes were identified. It was also noted that the correlations between these outcomes were small and non-significant. © 2012 Elsevier Ltd. Source

Garcia A.R.,University of Miami | Rahn I.,University of Miami | Johnson S.,University of Miami | Patel R.,University of Miami | And 8 more authors.
Colloids and Surfaces B: Biointerfaces | Year: 2013

Fluorescent insulin fibrils gold nanoclusters (Au NCs) have been synthesized through the reduction of gold by human insulin in fibrillated form. Likewise, nanocluster formation has been regulated by insulin, working as a protein-based template. Environment- and surface-controlled experiments have shown the optimized synthesis conditions is comprised of a pure aqueous alkaline solvent for insulin under constant heat at physiological temperature (37°C) prior to addition of the Au precursor (HAuCl4), followed by subsequent heating (37°C) and vigorous stirring after the addition of HAuCl4 until the completion of the synthetic approach. Microscopy experiments detected the presence of primordial fibril structures in samples of heated human insulin in the alkaline medium prior to addition of HAuCl4, while encountering more developed insulin fibrils in the terminal production of Au NCs. This investigation provides insight to the development of a novel synthesis of Au NCs in the alkaline medium, while providing a graphical description of the environmental and surface-dependent effects that were presented in the synthesis of human insulin nanoclusters. The study provides pertinent information for future synthetic procedures, as the protein state of several protein-nanoparticle systems may reflect on the results that were obtained herein. © 2013 Elsevier B.V. Source

Li S.,University of Miami | Mulloor J.J.,University of Miami | Wang L.,University of Miami | Ji Y.,University of Miami | And 5 more authors.
ACS Applied Materials and Interfaces | Year: 2014

Biosensing methods and devices using graphene oxide (GO) have recently been explored for detection and quantification of specific biomolecules from body fluid samples, such as saliva, milk, urine, and serum. For a practical diagnostics application, any sensing system must show an absence of nonselective detection of abundant proteins in the fluid matrix. Because lysozyme is an abundant protein in these body fluids (e.g., around 21.4 and 7 μg/mL of lysozyme is found in human milk and saliva from healthy individuals, and more than 15 or even 100 μg/mL in patients suffering from leukemia, renal disease, and sarcoidosis), it may interfere with detections and quantification if it has strong interaction with GO. Therefore, one fundamental question that needs to be addressed before any development of GO based diagnostics method is how GO interacts with lysozyme. In this study, GO has demonstrated a strong interaction with lysozyme. This interaction is so strong that we are able to subsequently eliminate and separate lysozyme from aqueous solution onto the surface of GO. Furthermore, the strong electrostatic interaction also renders the selective adsorption of lysozyme on GO from a mixture of binary and ternary proteins. This selectivity is confirmed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), fluorescence spectroscopy, and UV-vis absorption spectroscopy. © 2014 American Chemical Society. Source

Thames A.D.,University of California at Los Angeles | Hinkin C.H.,University of California at Los Angeles | Byrd D.A.,Mount Sinai School of Medicine | Bilder R.M.,University of California at Los Angeles | And 5 more authors.
Journal of the International Neuropsychological Society | Year: 2013

The purpose of the current study was to examine the predictive roles of stereotype threat and perceived discrimination and the mediating role of examiner-examinee racial discordance on neuropsychological performance in a non-clinical sample of African American and Caucasian individuals. Ninety-two African American (n = 45) and Caucasian (n = 47) adults were randomly assigned to either a stereotype threat or non-threat condition. Within each condition, participants were randomly assigned to either a same race or different race examiner. All participants underwent neuropsychological testing and completed a measure of perceived discrimination. African Americans in the stereotype threat condition performed significantly worse on global NP (Mz = -.30, 95% confidence interval [CI] [-0.07, -0.67] than African Americans in the non-threat condition (Mz = 0.09, CI [0.15, 0.33]. African Americans who reported high levels of perceived discrimination performed significantly worse on memory tests when tested by an examiner of a different race, Mz = -1.19, 95% CI [-1.78, -.54], than African Americans who were tested by an examiner of the same race, Mz = 0.24, 95% CI [-0.24, 0.72]. The current study underscores the importance of considering the role of contextual variables in neuropsychological performance, as these variables may obscure the validity of results among certain racial/ethnic groups. Copyright © INS. Published by Cambridge University Press, 2013. Source

Crawford N.F.,University of Miami | Micic M.,MP Biomedicals LLC | Micic M.,Cerritos College | Orbulescu J.,MP Biomedicals LLC | And 2 more authors.
Journal of Colloid and Interface Science | Year: 2015

The changes of interfacial properties of β-galactosidase introduced into different pH environments are investigated through surface chemistry and in situ spectroscopy. Conditions for an optimal Langmuir monolayer formation were firstly obtained by varying the subphase salt concentration and the surface-pressure area isotherm was used to extrapolate the limiting molecular area of the enzyme monolayer to be around 42,000Å2molecule-1. Surface pressure stability measurements held at 20mN/m for 90min along with compression-decompression cycles revealed no aggregate formation at the air-water interface. Consistent with the data obtained from the isotherm, in situ UV-Vis and fluorescence spectroscopy shows a steep rise in absorbance and photoluminescence intensity correlating to with a switch from a liquid-expanded to a liquid-condensed phase. A decrease in subphase pH increased the electrostatic repulsion as the enzyme was protonated, leading to an expanded monolayer. Infrared absorption-reflection spectroscopy demonstrates that the enzyme adopts mainly β-sheet conformation at the air-water interface before and during the compression. © 2015 Elsevier Inc. Source

Discover hidden collaborations