Adsorption and isolation of nucleic acids on cellulose magnetic beads using a three-dimensional printed microfluidic chip

While advances in genomics have enabled sensitive and highly parallel detection of nucleic acid targets, the isolation and extraction of the nucleic acids remain a critical bottleneck in the workflow. We present here a simple 3D printed microfluidic chip that allows for the vortex and centrifugation free extraction of nucleic acids. This novel microfluidic chip utilizes the presence of a water and oil interface to filter out the lysate contaminants. The pure nucleic acids, while bound on cellulose particles, are magnetically moved across the oil layer. We demonstrated efficient and rapid extraction of spiked Human Papillomavirus (HPV) 18 plasmids in specimen transport medium, in under 15 min. An overall extraction efficiency of 61% is observed across a range of HPV plasmid concentrations (5 × 10¹ to 5 × 10⁶ copies/100 μl). The magnetic, interfacial, and viscous drag forces inside the microgeometries of the chip are modeled. We have also developed a kinetics model for the adsorption of nucleic acids on cellulose functionalized superparamagnetic beads. We also clarify here the role of carrier nucleic acids in the adsorption and isolation of nucleic acids. Based on the various mechanistic insights detailed here, customized microfluidic devices can be designed to meet the range of current and emerging point of care diagnostics needs.     

Negotiating Language in Transnational Health Care: Exploring Translingual Literacy through Grounded Practical Theory

An increased interest in studying the nature of communication in health care and the use of interpreters has revealed the need for more collaboration and understanding of multilingual health-care practices. Theory and practice concerning cross-cultural health-care communication can benefit from examining the intersections between translingual literacy and transnational programs through hybrid interpretive strategies. In this study, I argue that these strategies move across, between, and among different languages, dialects, and nonverbal gestures to develop mutual understanding. To account for literacy practices that might engage this hybridity in health care, I use grounded practical theory to analyze a case study of participants who ran temporary medical and dental clinics in the Dominican Republic. This analysis finds that hybrid strategies with English–Spanish and Spanish–Spanish interpretation are used to overcome problems with balancing efficiency and rapport-building. By integrating ethnographic methods and grounded practical theory, this study's practical implications emerge in the negotiations of language employed by participants to connect translingual theory and practice in health-care communication.     

Trust and Authority in Scholarly Communications in the Light of the Digital Transition: setting the scene for a major study

The paper provides the results of the first phase of the research project Trust and Authority in Scholarly Communications in the Light of the Digital Transition. It provides for an examination of the behaviours and attitudes of academic researchers as producers and consumers of scholarly information resources in the digital era in respect to how they determine authority and trustworthiness in the sources they use, cite, and publish in. The first phase of the study utilized focus groups to formulate research questions for the project as a whole. It provided the direction for the literature review, interviews, and questionnaires studies that would follow. Fourteen focus groups were held in the UK and US in order to obtain this information. A total of 66 science and social science researchers participated. The main findings were: (a) researchers play down difficulties of establishing trustworthiness, not because there are none, but because they have well‐developed methods of establishing trust; (b) citation‐derived metrics are becoming more important in regard to where researchers publish; (c) social media are ancillary to research, but are used for promotion of research and idea generation; (d) researchers are suspicious and confused about open access, but less so if produced by a traditional publisher; (e) there was a uniformity of perceptions/behaviour of researchers irrespective of differences in subject, country, and age; (f) although some early career researchers behave the same as their more senior colleagues this is because of a fear of the system: they actually think differently.     

NEST 2014: Views from the Trainees—Talking About What Matters in Efforts to Diversify the STEM Workforce

This paper summarizes the outcomes of a retreat designed to cultivate interactions between trainees at various training levels and provide them opportunities to share their training perspectives and expectations. Retreat outcomes are used to support the development of better science, technology, engineering, and mathematics training practices by informing the trainers’ perspective.     

Microfluidic device capable of medium recirculation for non-adherent cell culture

We present a microfluidic device designed for maintenance and culture of non-adherent mammalian cells, which enables both recirculation and refreshing of medium, as well as easy harvesting of cells from the device. We demonstrate fabrication of a novel microfluidic device utilizing Braille perfusion for peristaltic fluid flow to enable switching between recirculation and refresh flow modes. Utilizing fluid flow simulations and the human promyelocytic leukemia cell line, HL-60, non-adherent cells, we demonstrate the utility of this RECIR-REFRESH device. With computer simulations, we profiled fluid flow and concentration gradients of autocrine factors and found that the geometry of the cell culture well plays a key role in cell entrapping and retaining autocrine and soluble factors. We subjected HL-60 cells, in the device, to a treatment regimen of 1.25% dimethylsulfoxide, every other day, to provoke differentiation and measured subsequent expression of CD11b on day 2 and day 4 and tumor necrosis factor-alpha (TNF-α) on day 4. Our findings display perfusion sensitive CD11b expression, but not TNF-α build-up, by day 4 of culture, with a 1:1 ratio of recirculation to refresh flow yielding the greatest increase in CD11b levels. RECIR-REFRESH facilitates programmable levels of cell differentiation in a HL-60 non-adherent cell population and can be expanded to other types of non-adherent cells such as hematopoietic stem cells.     

The National DNA Database on trial: engaging young people in South Wales with genetics

While there has been research conducted on public views about ethical and social aspects of the National DNA Database (NDNAD), there is little which focuses on views of young people, in particular those whose details are held on the NDNAD. We describe an engagement activity developed in South Wales to engage young offenders with ethical and social issues surrounding the NDNAD--a Mock Trial--and how we facilitated the presentation of their views to policy makers. We discuss the successes and challenges we encountered with engaging young offenders, decisions that the young people reached about possible future policies for the NDNAD at the Mock Trial, and their contribution to the decision-making process.