Microfluidic electromanipulation with capacitive detection for the mechanical analysis of cells

The mechanical behavior of cells offers insight into many aspects of their properties. We propose an approach to the mechanical analysis of cells that uses a combination of electromanipulation for stimulus and capacitance for sensing. To demonstrate this approach, polystyrene spheres and yeast cells flowing in a 25 μm×100 μm microfluidic channel were detected by a perpendicular pair of gold thin film electrodes in the channel, spaced 25 μm apart. The presence of cells was detected by capacitance changes between the gold electrodes. The capacitance sensor was a resonant coaxial radio frequency cavity (2.3 GHz) coupled to the electrodes. The presence of yeast cells (Saccharomyces cerevisiae) and polystyrene spheres resulted in capacitance changes of approximately 10 and 100 attoFarad (aF), respectively, with an achieved capacitance resolution of less than 2 aF in a 30 Hz bandwidth. The resolution is better than previously reported in the literature, and the capacitance changes are in agreement with values estimated by finite element simulations. Yeast cells were trapped using dielectrophoretic forces by applying a 3 V signal at 1 MHz between the electrodes. After trapping, the cells were displaced using amplitude and frequency modulated voltages to produce modulated dielectrophoretic forces. Repetitive displacement and relaxation of these cells was observed using both capacitance and video microscopy.     

Electronic reprints of freelance works: New York times v. Tasini

Conclusion Freelancers provide unique resources for publishers. Because of their special expertise, unique viewpoints, and even geographical location, they provide publishers with customized materials in disciplines and locations where the expense of full-time writers would not be justifiable. They will continue to be an important factor in the publishing industry. Publishers will continue to write contracts that allow them to republish articles in all known and future formats. Problems still exist with articles published before 1995. Publishers will have to decide how they will respond to Tasini, whether that means some version of the PRC or deleting articles. It is hoped that a final agreement between authors and publishers, according to the decision of the Supreme Court, will result in minimum inconvenience to the research public. New technology presents many challenges, as well as many opportunities, for freelance writers. As technology evolves, copyright law must ensure that writers’ incentives to create are nurtured and that they are fairly compensated for their work. Authors whose work creates value should share in the revenue and opportunities created by those technologies.     

From gentleman’s club to the marketplace: the library experience

In March this year I retired after a library career spent almost entirely in one institution. From this limited experience I hope to draw examples of changes in the library world, and their consequences, which I believe have general application.     

The Influence of Stigma on College Students' Attitudes Toward Online Video Counseling and Face‐to‐Face Counseling

The difference in attitudes toward online video counseling and face‐to‐face counseling and the relationship between stigma and these attitudes were investigated among a sample of 588 college students. Attitudes toward face‐to‐face counseling are more favorable compared with those toward online video counseling. However, self‐stigma does not influence attitudes toward online video counseling to the same extent as face‐to‐face counseling. Services delivered through online video counseling may be beneficial for those experiencing higher levels of stigma.     

Association between early sexual abuse and adult HIV-risky sexual behaviors among community-recruited women.

OBJECTIVE: The first purpose was to determine whether sexual abuse involving penetration that occurred in childhood only, adolescence only, or both childhood and adolescence differently impacted whether community-recruited women had ever traded sex for money or drugs, their number of recent sex partners, and the number of times they had engaged in recent unprotected sex. The second purpose was to assess the mediating effects of adulthood rape, recent drug use, and recent sex with an injection drug user on these three HIV-risky sexual behaviors. METHOD: Women (n = 1,490) recruited from three US sites were questioned about their childhood and/or adolescent sexual abuse histories, adulthood rape experiences, recent drug use, and adult HIV-risky sexual behaviors via structured interviews. RESULTS: One-third of the women reported having experienced sexual abuse involving penetration in childhood and/or adolescence. Overall, regression analyses indicated a significant relationship between early sexual abuse and adult risky behaviors; rape in adulthood mediated this relationship for all three HIV-risky behaviors. Abuse that occurred in childhood only and abuse that occurred in both childhood and adolescence had a stronger impact on later risky behaviors than did abuse that occurred in adolescence only. CONCLUSIONS: Because childhood constitutes a critical period in individuals' sexual, social, and personal development, sexual abuse precipitated during this time may distort women's constructions of sex and sexuality. Women abused in childhood may therefore engage in HIV-risky sexual behaviors to a greater extent than women abused in adolescence as a result of these disruptions to their development. Rape in adulthood appears to intensify the effects of early sexual abuse,     

Learning with and from: positioning school students as advisors in pre-service teacher education

This article reports on an innovative pedagogical approach within the Learning Partnerships program in which school students help to ‘teach the teachers’ within pre-service teacher education. Classes of school students join with classes of pre-service teachers to provide input on how teachers can enhance school students’ engagement and wellbeing. The article draws on data collected from 125 students (aged 13–16) and 120 pre-service teachers in these workshops. Findings generated from a mixed methods study combining pre-workshop focus groups (n = Students: 38, Teachers: 33) and post-workshop focus groups (n = Students: 69, Teachers: 15) and post-workshop surveys (n = Students: 96; Teachers: 101) demonstrated that the workshops were mutually beneficial for both students and pre-service teachers. Participants found that workshopping together enhanced their belief in the possibility of positive student–teacher relationships. The pre-service teachers reported greater confidence in communicating with young people about the issues that affect student engagement and wellbeing. The school students reported that they were more willing to use teachers as a source of help. Implications include the need for increased attention to a ‘third space’ for learning in teacher development which provides opportunity for learning with and from young people about how to foster their engagement and wellbeing.     

The Relative Effect of a Code-Oriented and a Meaning-Oriented Early Literacy Program on Regular and Low Progress Australian Students in Year 1 Classrooms which Implement Reading Recovery

A within-school study of the effects of two different early literacy instructional programs on the reading proficiency of Year 1 students was undertaken in three schools in New South Wales, Australia all of which used Reading Recovery. The first program under examination was a "meaning"-oriented program used by six Kindergarten and Year 1 classrooms in the three schools. The second program, a "code"-oriented one, was implemented in the same six Kindergarten and Year 1 classrooms one year later. The code-oriented program, known as Schoolwide Early Language and Literacy (SWELL), stresses the explicit instruction of phonological awareness and the alphabetic code in context. All students, including both regular and Reading Recovery students, in the six non-SWELL classrooms were tested on four early literacy measures at the end of Year 1 when they had completed two years of schooling (comparison group). At the end of the following year, all Year 1 students in the six SWELL classrooms were tested on the same early literacy measures, when they had completed two years of schooling (experimental group). Results indicated that all regular and Reading Recovery students in SWELL classes significantly outperformed their regular and Reading Recovery counterparts in non-SWELL classes on tests measuring pseudoword decoding, reading connected text, invented spelling, and a standardised reading measure at the end of Year 1. However, Reading Recovery students as a group, whether in SWELL or non-SWELL classes, did not reach the average level of their peers on any of the four literacy measures used. Implications for the most effective combination of whole-class and tutorial programs for children at-risk of literacy failure are considered in the discussion.     

The role of outdoor recreation in family enrichment

The family is the fundamental unit in society and perhaps the oldest and most important of all human institutions. Several studies have indicated a positive correlation between strong, successful families and family participation in outdoor recreational activities. This paper addresses the role of structured outdoor recreation programming in family enrichment. Findings from two studies based in the United States are presented: one on the effect of a one-day family outdoor adventure program on parental and child perceptions of family functioning and the other from a qualitative inquiry into the meaning of family residential camping experiences. The first study collected both quantitative and qualitative data from 24 families who participated in an 8-hour outdoor adventure program. The second study utilized structured interviews with 11 families participating in a residential camp experience. Findings from both studies demonstrate that structured outdoor family recreation programming has a strong positive relationship with family strength. Furthermore, findings indicate that the type of outdoor adventure activities being used in the treatment of dysfunctional and maladaptive families is also effective in providing family enrichment experiences.