A parallel microfluidic channel fixture fabricated using laser ablated plastic laminates for electrochemical and chemiluminescent biodetection of DNA

Herein is described the fabrication and use of a plastic multilayer 3-channel microfluidic fixture. Multilayer devices were produced by laser machining of plastic polymethylmethacrylate and polyethyleneterapthalate laminates by ablation. The fixture consisted of an array of nine individually addressable gold or gold/ITO working electrodes, and a resistive platinum heating element. Laser machining of both the fluidic pathways in the plastic laminates, and the stencil masks used for thermal evaporation to form electrode regions on the plastic laminates, enabled rapid and inexpensive implementation of design changes. Electrochemiluminescence reactions in the fixture were achieved and monitored through ITO electrodes. Electroaddressable aryl diazonium chemistry was employed to selectively pattern gold electrodes for electrochemical multianalyte DNA detection from double stranded DNA (dsDNA) samples. Electrochemical detection of dsDNA was achieved by melting of dsDNA molecules in solution with the integrated heater, allowing detection of DNA sequences specific to breast and colorectal cancers with a non-specific binding control. Following detection, the array surface could be renewed via high temperature (95 °C) stripping using the integrated heating element. This versatile and simple method for prototyping devices shows potential for further development of highly integrated, multi-functional bioanalytical devices.     

Integrated carbon fiber electrodes within hollow polymer microneedles for transdermal electrochemical sensing

In this study, carbon fiber electrodes were incorporated within a hollow microneedle array, which was fabricated using a digital micromirror device-based stereolithography instrument. Cell proliferation on the acrylate-based polymer used in microneedle fabrication was examined with human dermal fibroblasts and neonatal human epidermal keratinocytes. Studies involving full-thickness cadaveric porcine skin and trypan blue dye demonstrated that the hollow microneedles remained intact after puncturing the outermost layer of cadaveric porcine skin. The carbon fibers underwent chemical modification in order to enable detection of hydrogen peroxide and ascorbic acid; electrochemical measurements were demonstrated using integrated electrode-hollow microneedle devices.     

Effects of Diverse STEM Role Model Videos in Promoting Adolescents’ Identification

International Journal of Science and Mathematics Education - Role models are critical for broadening participation in science, technology, engineering, and mathematics (STEM); however, little is...     

WOMEN FULL-TIME FACULTY OF COLOR IN 2-YEAR COLLEGES: A TREND AND PREDICTIVE ANALYSIS

This study involved trend and predictive analyses to examine changes in the proportional representation of women full-time faculty by race/ethnicity from 1991 to 1997 in a sample of 1,024 matched two-year colleges. Large, Hispanic-serving, Historically Black, and California two-year colleges, along with the percentage of women administrators of color entered as significant positive predictors of change in the proportional representation of women full-time faculty of color. These findings open the door, not only to new ways of informing policy development and practice, but also to future research that can uncover new understandings of gender and race-equitable practices in two-year colleges.     

Building a whole school approach and teacher efficacy with English language learners

Current professional development initiatives show a preference for whole school approaches. However, pedagogy related to English language learners (ELLs) is often not widely dispersed in New Zealand primary schools, impacting on teacher efficacy with these learners. This paper discusses findings from a qualitative study which aimed to identify influences shaping the dispersal of ELL-related pedagogy in two schools in contrasting socio-economic areas. Data from semi-structured individual interviews with teachers at different class levels revealed unique patterns for the dispersal of ELL-related pedagogy in each school. Teacher data indicated that these patterns were influenced by the performance of ELLs in national standards testing, as well as the special characteristics of ELLs in each setting and the distinctive nature of each context. The dispersal of ELL pedagogy in each school impacted differentially on opportunities to build a sense of collective teaching efficacy with ELLs in that setting, but also raised questions about whether one size should be expected to fit all.     

Using Typical Infant Development to Inform Music Therapy with Children with Disabilities

This article illustrates some ways in which observations of typically-developing infants can inform music therapy and other work with children with disabilities. The research project that is described examines typical infant development with special attention to musical relatedness and communication. Videotapes of sessions centering on musical play with typically-developing infants and of music therapy sessions of children with multiple severe disabilities are examined in light of developmental issues, conceptual frameworks, and relationships between typical development and developmental issues of children with disabilities. Greenspan’s model of psychosocial development is used as a basis for analyzing observations. This research was conducted over a period of several years. Portions of what is reported here were presented at the European Music Therapy Congress, Naples, Italy (Wheeler and Stultz 2001) and the 10th World Congress of Music Therapy, Oxford, UK (Wheeler and Stultz 2002). Thanks to Elizabeth Rightmyer for very helpful feedback on the article.