An off-the-shelf integrated microfluidic device comprising self-assembled monolayers for protein array experiments

Microfluidic-based protein arrays are promising tools for life sciences, with increased sensitivity and specificity. One of the drawbacks of this technology is the need to create fresh surface chemistry for protein immobilization at the beginning of each experiment. In this work, we attempted to include the process of surface functionalization as part of the fabrication of the device, which would substitute the time consuming step of surface functionalization at the beginning of each protein array experiment. To this end, we employed a novel surface modification using self-assembled monolayers (SAMs) to immobilize biomolecules within the channels of a polydimethylsiloxane (PDMS) integrated microfluidic device. As a model, we present a general method for depositing siloxane-anchored SAMs, with 1-undecyl-thioacetate-trichlorosilane (C₁₁TA) on the silica surfaces. The process involved developing PDMS-compatible conditions for both SAM deposition and functional group activation. We successfully demonstrated the ability to produce, within an integrated microfluidic channel, a C₁₁TA monolayer with a covalently conjugated antibody. The antibody could then bind its antigen with a high signal to background ratio. We further demonstrated that the antibody was still active after storage of the device for a week. Integration of the surface chemistry into the device as part of its fabrication process has potential to significantly simplify and shorten many experimental procedures involving microfluidic–based protein arrays. In turn, this will allow for broader dissemination of this important technology.     

Question Asking in the Science Classroom: Teacher Attitudes and Practices

Despite the wide agreement among educators that classroom learning and teaching processes can gain much from student and teacher questions, their potential is not fully utilized. Adopting the view that reporting both teachers’ (of varying age groups) views and actual classroom practices is necessary for obtaining a more complete view of the phenomena at hand, the present study closely examines both cognitive and affective domains of: (a) teachers’ views (via interviews) concerning: (1) importance and roles of teacher and student questions, (2) teacher responses, and (3) planning and teacher training; and (b) teachers’ actual practices (via classroom observations) concerning: (1) number and (2) level of teacher and student questions, as well as (3) teachers’ responses to questions. The data were collected from 3 elementary, 3 middle, and 3 high school science teachers and their respective classroom students. The findings lay out a wide view of classroom questioning and teachers’ responses, and relate what actually occurs in classes to teachers’ stated views. Some of the study’s main conclusions are that a gap exists between how science researchers and teachers view the role of teacher questions: the former highlight the cognitive domain, while the latter emphasize the affective domain.     

Shedding further light on the effects of various types and quality of early child care on infant-mother attachment relationship: the Haifa Study of Early Child Care

The Haifa Study of Early Child Care recruited a large-scale sample (N = 758) that represented the full SES spectrum in Israel, to examine the unique contribution of various child-care-related correlates to infant attachment. After controlling for other potential contributing variables--including mother characteristics, mother-child interaction, mother-father relationship, infant characteristics and development, and the environment--this study found that center-care, in and of itself, adversely increased the likelihood of infants developing insecure attachment to their mothers as compared with infants who were either in maternal care, individual nonparental care with a relative, individual nonparental care with a paid caregiver, or family day-care. The results suggest that it is the poor quality of center-care and the high infant-caregiver ratio that accounted for this increased level of attachment insecurity among center-care infants.     

Mothers’ mental-state discourse with preschoolers during storybook reading and wordless storybook telling

Recent research has shown that parents, through conversations during shared book reading, play a pivotal role in promoting children's social cognition, particularly their theory of mind (ToM). This study compared mothers’ mental-state discourse during two kinds of interactions with their children – storybook reading and wordless storybook telling. In both contexts, mothers were familiar with the books’ texts but relied to a different extent on the texts during the mother–child interactions. Participants were 72 Israeli mothers and their 4- to 6-year-old children, from an upper–middle socioeconomic level. Mothers were instructed to read or tell two stories as they normally would. Two books were used, similar in several major characteristics – author, illustrator, characters, story length, and false belief as a central theme. Main findings revealed that mothers referred to mental states in both situations, but during storytelling, mothers elaborated more, referring to characters’ cognitive states and false beliefs, than during storybook reading. Findings suggest that storytelling encourages rich discussions on important sociocognitive elements. Educators and parents should be aware of the contribution of storybook reading and storybook telling to mental-state talk and of the unique potential of storybook telling to encourage conversation on ToM-related topics.     

Emerging Conceptual Understanding of Complex Astronomical Phenomena by Using a Virtual Solar System

This study describes high school students' conceptual development of the basic astronomical phenomena during real-time interactions with a Virtual Solar System (VSS). The VSS is a non-immersive virtual environment which has a dynamic frame of reference that can be altered by the user. Ten 10th grade students were given tasks containing a set of observe–explain questions without mentoring. The findings showed that all participants used the VSS as a visual thinking tool and developed a scientific understanding of the causes of the day–night phenomena. However, alternative dynamic misconceptions of the Earth–Moon–Sun system emerged as a result of (1) cognitive difficulty in coordinating visual information from different perspectives; (2) misinterpreting salient features of the VSS visual representation; (3) ignoring the 3D nature of the Moon's relative motion, together with incorrect perception of the Moon's and the Earth's relative size and distance; and (4) the inability to mentally shift away from the Earth's frame of reference. These findings have significant bearing on our understanding of the educational potential and possible pitfalls of learning via virtual reality environments. The learning should be accompanied by suitable scaffolding and guided reflection to minimize the emergence of alternative astronomical conceptions. Designing additional navigation tools would empower the learners' perceptual and cognitive system.     

Modern pedagogy,local concerns: the Junkyard on the kibbutz kindergarten

This paper focuses on the “Junkyard” (chatzar grutaot) – a unique educational environment and practice developed in kindergartens on the Israeli kibbutz in the 1940s and 1950s, and still in wide use today in kibbutz kindergartens. The Junkyard, consisting of artefacts of the adult world that are no longer in use, is an ever-changing set-up in which children’s free play is encouraged, with minimal rules for use of time, space, objects, and social relations. Anchored in the writings of its two founding educators, as well as in writings of and interviews with its advocates and instructors over the years, this paper shows how the Junkyard drew on widespread ideas about early childhood development and education, at the same time as it responded to local conditions and concerns. The paper argues that a unique conjunction of factors – material and structural, educational and pedagogical, ideological and cultural – facilitated the process by which the Junkyard was inserted relatively smoothly into the kibbutz educational landscape, in lasting ways.