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In this review, we present nanofluidic phenomena, particularly as they relate to applications involving analysis of biomolecules within nanofabricated devices. The relevant length scales and physical phenomena that govern biomolecule transport and manipulation within nanofabricated nanofluidic devices are reviewed, the advantages of nanofabricated devices are presented, and relevant applications are cited. Characteristic length scales include the Debye length, the Van der Waals radius, the action distance of hydrogen bonding, the slip length, and macromolecular dimensions. On the basis of the characteristic lengths and related nanofluidic phenomena, a nanofluidic toolbox will be assembled. Nanofluidic phenomena that affect biomolecule behavior within such devices can include ion depletion and enrichment, modified velocity and mobility, permselectivity, steric hindrance, entropy, adsorption, and hydrodynamic interaction. The complex interactions and coupled physics of such phenomena allow for many applications, including biomolecule separation, concentration, reaction/hybridization, sequencing (in the case of DNA) and detection. Examples of devices for such applications will be presented, followed by a discussion of near-term challenges and future thoughts for the field.

This study examines how strength of ethnic identity, multiethnic identity, and other indicators of biculturalism relate to the drug use norms of urban American Indian middle school students. The article distinguishes categories of norms that may affect drug use. Regression analysis of self-reports by 434 American Indian seventh graders attending middle schools in a large southwestern U.S. city indicated that students who had a more intense sense of ethnic pride adhered more strongly to certain antidrug norms than those who did not. Whereas American Indian students with better grades in school held consistently stronger antidrug norms, there were few differences by gender, socioeconomic status, or age. These results have implications in social work practice for better understanding and strengthening the protective aspects of American Indian culture in drug prevention efforts.

This article discusses the results of three elementary school teachers' feedback from a mindfulness-training program. Mindfulness is the ability to pay attention to what's happening now without judgment. The training consisted of breathwork, bodyscan, movement, and sensorimotor activities. Results of interviews with the teachers revealed that teachers used the mindfulness skills to (a) aid in curriculum development and implementation, (b) deal with conflict and anxiety, (c) improve the quality of their personal lives, and (d) facilitate positive changes in the classroom.The role of a teacher has changed over the decades. Historically, teachers focused primarily on the cognitive development of children, more specifically, the "three Rs" of reading, writing, and arithmetic. Today's society has set new norms for family life, therefore, restructuring the role of the teacher. Mobility of families, the dwindling extended family, twoworking-parent families, and single-parent families have created new and added demands for the school and teacher.Teachers are now expected to be aware of the emotional challenges children face and are required to have the tools to deal with them. The increase in attention deficit hyperactivity disorder (ADHD), stress, depression, and anxiety in students places more demands on teachers' knowledge and skills. The consistent increase in the number of students entering higher education has placed added pressure on teachers to develop appropriate curriculums. When we are mindful, we are able to increase our ability to pay attention. Developing the practice of mindfulness can help teachers meet the stressful challenges that confront them today.This article discusses the incidence of stress and attention problems experienced by children and ultimately their teachers. Results of interviews with 1 fourth-grade and 2 thirdgrade teachers regarding their mindfulness-training experience are reported. It is hypothesized that with the increase in stress and overload of incoming information, children and teachers will benefit from mindfulness training by dealing with stress more effectively and by increasing their ability to focus. The purpose of the program was to see how the practice of 31

In this article, we investigate the effects of pH, ionic strength, and channel height on the mobility and diffusivity of charged spherical particles within planar microfluidic channels. Specifically, we report results of a broad experimental study on the transport and separation behavior of 50 and 100 nm spherical carboxylated polystyrene nanoparticles, confined in 20 lm, 1 lm, and 250 nm deep fluidic channels. We find that pH, ionic strength, and channel height have coupled impacts on mobility changes. In particular, we show that, depending on pH, the dependence of particle mobility on channel size can have opposing behavior. In addition, we also show that at the nanoscale, at lower ionic strengths, there is a substantial increase in mobility, due to enhanced electric fields within the nanochannels. These effects are important to understand in order to avoid potential downfalls in terms of separation efficiency as well as design for better tuning of separation performance in micro-and nanochannels. Finally, we propose a method to estimate the effective zeta potential of spherical particles from measured electrophoretic mobility data. This could prove useful in characterizing a heterogeneous collection of particles having a distribution over a range of values of the zeta potential.