Hybrid capillary-inserted microfluidic device for sheathless particle focusing and separation in viscoelastic flow

A novel microfluidic device which consists of two stages for particle focusing and separation using a viscoelastic fluid has been developed. A circular capillary tube was used for three-dimensional particle pre-alignment before the separation process, which was inserted in a polydimethylsiloxane microchannel. Particles with diameters of 5 and 10 μm were focused at the centerline in the capillary tube, and the location of particles was initialized at the first bifurcation. Then, 5 and 10 μm particles were successfully separated in the expansion region based on size-dependent lateral migration, with ∼99% separation efficiency. The proposed device was further applied to separation of MCF-7 cells from leukocytes. Based on the cell size distribution, an approximate size cutoff for separation was determined to be 16 μm. At 200 μl/min, 94% of MCF-7 cells were separated with the purity of ∼97%. According to the trypan blue exclusion assay, high viability (∼90%) could be achieved for the separated MCF-7 cells. The use of a commercially available capillary tube enables the device to be highly versatile in dealing with particles in a wide size range by using capillary tubes with different inner diameters.     

Infant Attachment Security and Early Childhood Behavioral Inhibition Interact to Predict Adolescent Social Anxiety Symptoms

Insecure attachment and behavioral inhibition (BI) increase risk for internalizing problems, but few longitudinal studies have examined their interaction in predicting adolescent anxiety. This study included 165 adolescents (ages 14–17 years) selected based on their reactivity to novelty at 4 months. Infant attachment was assessed with the Strange Situation. Multimethod BI assessments were conducted across childhood. Adolescents and their parents independently reported on anxiety. The interaction of attachment and BI significantly predicted adolescent anxiety symptoms, such that BI and anxiety were only associated among adolescents with histories of insecure attachment. Exploratory analyses revealed that this effect was driven by insecure‐resistant attachment and that the association between BI and social anxiety was significant only for insecure males. Clinical implications are discussed.     

Perceptions of Retirement Affect Career Commitment: The Mediating Role of Retirement System Satisfaction for Two Teacher Age Groups

This study investigated a sample of California elementary, intermediate, and high school employed teachers (N = 247) to assess the effects of retirement perceptions on career commitment among teachers who are in different age groupings. Using path analysis, the influence of five retirement perceptions variables was examined: concerns about retirement benefits, understanding of the retirement system, perceived need for system change, control over the retirement plan, and satisfaction with current salary. The results indicated that the pattern of results differed for younger and older teachers. For the younger (age 21–45) group, concerns about retirement benefits (such as losing or reducing benefits through geographic mobility) and control over the retirement plan had significant, large, and direct effects on career commitment. For the older (age 46+) group, retirement variables had a significant effect on career commitment via the mediator of satisfaction with the retirement system. Given these findings, for younger teachers, strategies might focus on providing greater control over the retirement plan, such as in offering choice in how their retirement monies are invested. Older teachers need to feel safe about retirement in the sense of being satisfied with the system and its benefits to commit to their jobs.     

Big Math for Little Kids: The Effectiveness of a Preschool and Kindergarten Mathematics Curriculum

Research Findings: Big Math for Little Kids (BMLK) is a mathematics curriculum developed for use with 4- and 5-year-old children. To investigate the BMLK curriculum's effect on children's mathematics knowledge, this cluster-randomized controlled trial randomly assigned child care centers to provide mathematics instruction to children, using either the BMLK mathematics curriculum or the centers’ business-as-usual curriculum, over a 2-year period when children were in prekindergarten and kindergarten. Participants in the study were 762 children and their teachers at 16 publicly subsidized child care centers. The study assessed children's mathematics knowledge using the Early Childhood Longitudinal Study, Birth Cohort (ECLS-B), Direct Mathematics Assessment, a measure of young children's mathematics knowledge that is not aligned with the curriculum. The ECLS-B scores of children in the BMLK group increased significantly more than did those of children in the comparison group. The study also included exploratory analyses to examine whether children in the BMLK group demonstrated evidence of improved mathematical language. Practice or Policy: These results indicate that the BMLK curriculum, which is designed to help teachers use play-based, developmentally appropriate mathematics instruction, has a positive impact on young children's mathematics knowledge as measured by a general mathematics assessment that is not aligned with the curriculum.     

Musculoskeletal stiffness during hopping and running does not change following downhill backwards walking

Eccentric contractions that provide spring energy can also cause muscle damage. The aim of this study was to explore leg and vertical stiffness following muscle damage induced by an eccentric exercise protocol. Twenty active males completed 60 minutes of backward-walking on a treadmill at 0.67 m/s and a gradient of ? 8.5° to induce muscle damage. Tests were performed immediately before; immediately post; and 24, 48, and 168 hours post eccentric exercise. Tests included running at 3.35 m/s and hopping at 2.2 Hz using single- and double-legged actions. Leg and vertical stiffness were measured from kinetic and kinematic data, and electromyography (EMG) of five muscles of the preferred limb were recorded during hopping. Increases in pain scores (over 37%) occurred post-exercise and 24 and 48 hours later (p < 0.001). A 7% decrease in maximal voluntary contraction occurred immediately post-exercise (p = 0.019). Changes in knee kinematics during single-legged hopping were observed 168 hours post (p < 0.05). No significant changes were observed in EMG, creatine kinase activity, leg, or vertical stiffness. Results indicate that knee mechanics may be altered to maintain consistent levels of leg and vertical stiffness when eccentric exercise-induced muscle damage is present in the lower legs.     

What does ‘inclusion’ mean for pupils on the autistic spectrum in mainstream secondary schools?

The last decade has seen a groundswell of developments in educational policy in the UK relating to inclusive education for students with special educational needs (SEN). However, whether government policy has been fully implemented in schools remains a concern. The experience of students with autistic spectrum disorders (ASDs) provides an excellent case in point. An increasing number of such students are now educated in mainstream schools, but the limited research in this area has indicated that their experience of school is often marked by bullying, social isolation and anxiety. In light of this, the aim of the current study was to examine the extent to which inclusive educational policy was actually reflected in the practices of four mainstream secondary schools. An exploratory case study approach was adopted, utilising interviews with pupils, teachers, other school staff (e.g., senior managers, learning support assistants) and parents, observations of lessons and other contexts (e.g., lunch time), and document analysis. Our findings highlighted a number of school practices which acted as facilitators or barriers to students’ learning and participation, some of which were generic to SEN provision, and some of which appeared to be specific to those on the autistic spectrum. A discussion of these is presented to enable further understanding of, and inform practice relating to, the inclusion process for students with ASDs.