Platinum functionalized titania nanotube array sensor for detection of Trichloroethylene in water

pre-printA sensor using platinum functionalized titania nanotubes for the detection of Trichloroethylene (TCE) in water samples has been developed. The titania nanotubes were synthesized using an electrochemical anodization technique and platinum was photocatalytically deposited on the nanotubes. The sensor exhibits a good response to TCE concentrations in the range of 10 to 1000 ppm

Optimization and characterization of a microscale thermal field-flow fractionation system

Journal ArticleA thorough investigation of the design considerations for microscale thermal field-flow fractionation and characterization of a 25 μm thin microscale thermal field-flow fractionation system is reported. A 4-50 times volume reduction from mesoscale and macroscale systems warrants customized design and operational conditions for microscale separation systems. Theoretical calculations are done to illustrate the importance of the increased dispersion due to extra-column tubing, off-chip detection and sample injection volume with reduced channel dimensions. An optimized microscale thermal field-flow fractionation (ThFFF) channel is fabricated using rapid and cost effective manufacturing and assembly processes. Specifically, improvements in material selection and arrangement are implemented to achieve higher particle retentions. The new instrument arrangement includes high conductivity silicon as the cold wall and a thin polymer layer with low thermal conductivity as the hot wall which results in high temperature gradients (~ 106 ºC/m) across the microchannel and subsequently high retention. Single particle retention separations are carried out with polystyrene nanoparticle samples in an aqueous carrier to characterize the device and demonstrate the improvements

Cyclical magnetic field flow fractionation

Journal ArticleIn this study, a new magnetic field flow fractionation (FFF) system was designed and modeled by using finite element simulations. Other than current magnetic FFF systems, which use static magnetic fields, our system uses cyclical magnetic fields. Results of the simulations show that our cyclical magnetic FFF system can be used effectively for the separation of magnetic nanoparticles. Cyclical magnetic FFF system is composed of a microfluidic channel (length¼5 cm, height¼30 lm) and 2 coils. Square wave currents of 1Hz (with 90 deg of phase difference) were applied to the coils. By using Comsol Multiphysics 3.5a, magnetic field profile and corresponding magnetic force exerted on the magnetite nanoparticles were calculated. The magnetic force data were exported from Comsol to Matlab. In Matlab, a parabolic flow profile with maximum flow speed of 0.4mL/h was defined. Particle trajectories were obtained by the calculation of the particle speeds resulted from both magnetic and hydrodynamic forces. Particle trajectories of the particles with sizes ranging from 10 to 50 nm were simulated and elution times of the particles were calculated. Results show that there is a significant difference between the elution times of the particles so that baseline separation of the particles can be obtained. In this work, it is shown that by the application of cyclical magnetic fields, the separation of magnetic nanoparticles can be done efficiently

Characterization of a microscale thermal-electrical field-flow fractionation system

ManuscriptA microscale thermal-electrical field-flow fractionation (ThElFFF) channel is reported for the first time and preliminary characterization results show high retention at certain operating conditions including relatively high flow rates when compared to standard microscale electrical or thermal field-flow fractionation instruments. A new design is presented that simplifies manufacturing and assembly of the prototype and that can provide both an electrical field and a high temperature gradient (~ 106 ?C/m). Monodisperse particle retention is carried out with polystyrene nanoparticle samples to characterize the device. Retention ratios as low as 0.045 are observed with the ThElFFF instrument. Size selectivity of 1.77 was achieved for ThElFFF. The comparison with theory shows a marked deviation from the existing theory. Separation of a mixture of polystyrene particles is demonstrated for first time using a ThElFFF system by separating 130 nm carboxylated polystyrene and 209 nm polystyrene particles

Ethical Issues and Decision Making in Collaborative Financial Therapy

The purpose of this article is to introduce potential ethical challenges that may arise when a financial and mental health professional collaborate to provide financial therapy and recommendations on how to effectively address these concerns. The development of ethical and professional practices requires extensive dialogue from practitioners in the emerging field of financial therapy; however, it is important to first develop an awareness and sensitivity to the ethical and professional issues across disciplines. This article examines the differences and similarities between the codes of ethics of different financial and mental health disciplines, and addresses six core ethical and professional issues: dual relationships, confidentiality, collaborating with other professionals, fee management, use of technology, and attending to federal and state regulatory laws. In working through the complexity of different disciplines’ regulatory environments, a discussion of how to address these ethical questions in order to progress the financial therapy field is presented

Cosmic Origins Program Annual Technology Report

What is the Cosmic Origins (COR) Program? From ancient times, humans have looked up at the night sky and wondered: Are we alone? How did the universe come to be? How does the universe work? COR focuses on the second question. Scientists investigating this broad theme seek to understand the origin and evolution of the universe from the Big Bang to the present day, determining how the expanding universe grew into a grand cosmic web of dark matter enmeshed with galaxies and pristine gas, forming, merging, and evolving over time. COR also seeks to understand how stars and planets form from clouds in these galaxies to create the heavy elements that are essential to life starting with the first generation of stars to seed the universe, and continuing through the birth and eventual death of all subsequent generations of stars. The COR Programs purview includes the majority of the field known as astronomy, from antiquity to the present

Transcript of Selected Panelist Remarks from IA’s Plenary on Assessment October 2, 2009

This transcript includes panelist remarks by: Bruce Burgett, Professor and Director, Interdisciplinary Arts and Sciences, University of Washington, Bothell; Fluney Hutchinson, Professor, Economics, Lafayette College; Sylvia Gale, Associate Director, Bonner Center for Civic Engagement, University of Richmond; Dudley Cocke, Director, Roadside Theater/ Appalshop; and George Sanchez, Director, Center for Diversity and Democracy, University of Southern California

Gel electrophoretic profiles of proteinases in dark-germinated flax seeds

The proteinases present in dark-germinated flax seeds (Linum usitatissimum) were studied as a function of germination at 25°C. A majority of activity was present in basic proteinases with an acidic pH optimum and a temperature optimum of 45°C in the digestion of hemoglobin. Electrophoresis in a sodium dodecyl sulfate-polyacrylamide mixture which had been polymerized with gelatin was used to separate proteins in extracts of seedlings. Subsequent activation of proteinases with Triton X-100 and resultant digestion of gelatin proved to be very reproducible and afforded detection and good quantification of various proteinase zones. An ethylenediaminetetraacetate-sensitive proteinase zone, P4 (about 60,000 daltons), appeared at day 3 after imbibition and attained maximum activity at day 4. This correlates with a rapid loss in vivo of the glyoxysomal enzyme, isocitrate lyase (EC 4.1.3.1). Ethylenediaminetetraacetate also slowed the loss of isocitrate lyase activity in extracts of 4-day seedlings in a dose-dependent manner. The addition of leupeptin,α -tolylsulfonyl fluoride, Pepstatin A, p-chloromercuribenzoate, or 1,10-phenanthroline prior to, during, or after exchange of Triton X-100 for sodium dodecyl sulfate had almost no inhibitory effect upon proteinases in 4-day seedlings

Assessing the Needs of Utah Dairy Farmers to Inform Extension Programming

A needs assessment was conducted by the Utah State University Dairy Extension Team to identify the most urgent issues faced by Utah dairy farmers. The assessment found that the top five priority needs were implementing new technology, improving public perception of water use, managing risk, succession planning, and reducing feed costs. The results will guide dairy Extension programming in Utah. Several workshops and events have already been planned to address these needs. Overall, the assessment will help USU Extension provide research-based educational programs to meet the needs of the dairy industry in Utah