End-functionalized glycopolymers as mimetics of chondroitin sulfate proteoglycans

Glycosaminoglycans are sulfated polysaccharides that play important roles in fundamental biological processes, such as cell division, viral invasion, cancer and neuroregeneration. The multivalent presentation of multiple glycosaminoglycan chains on proteoglycan scaffolds may profoundly influence their interactions with proteins and subsequent biological activity. However, the importance of this multivalent architecture remains largely unexplored, and few synthetic mimics exist for probing and manipulating glycosaminoglycan activity. Here, we describe a new class of end-functionalized ring-opening metathesis polymerization (ROMP) polymers that mimic the native-like, multivalent architecture found on chondroitin sulfate (CS) proteoglycans. We demonstrate that these glycopolymers can be readily integrated with microarray and surface plasmon resonance technology platforms, where they retain the ability to interact selectively with proteins. ROMP-based glycopolymers are part of a growing arsenal of chemical tools for probing the functions of glycosaminoglycans and for studying their interactions with proteins

“Just challenge those high-ability learners and they’ll be all right!” The impact of social context and challenging instruction on the affective development of high-ability students

This study provided a voice to gifted elementary children attending three very different schools that endeavoured to meet their atypical academic needs. While educators have theorised that special programs for gifted students benefit gifted children academically and contribute positively to their social and emotional development, there is limited research to support this belief. The phenomenological framework used in this study allowed 27 gifted elementary students to present their perceptions of the advantages and disadvantages of extension class environments. The results demonstrate that while challenging instruction was clearly important for the emotional wellbeing of the advanced learners, it went hand in hand with the schools’ ethoi in relation to the social and emotional development of their student populations. The schools’ objectives clearly influenced students’ perceptions of emotional safety, acceptance of diversity, and teacher-student and peer relations in the schools. This finding differs to previous research results, which suggest that if a gifted child’s cognitive abilities are catered for, her or his social and emotional needs will automatically be met. While this study found that the social context of the school played an important role in the talent process, a strong relationship was also found between program type and sociaffective outcomes

Seasonal and Local Solar Time Variation of the Meridional Wind at 95 km from Observations of the 11.072-GHz Ozone Line and the 557.7-nm Oxygen Line

Ground-based spectrometers have been deployed to measure the concentration, velocity, and temperature of ozone in the mesosphere and lower thermosphere (MLT), using low-cost satellite television electronics to observe the 11.072-GHz line of ozone. The ozone line was observed at an altitude near 95 km at 38°N, 71°W using three spectrometers located at the Massachusetts Institute of Technology’s Haystack Observatory (Westford, Massachusetts), Chelmsford High School (Chelmsford, Massachusetts), and Union College (Schenectady, New York), each pointed south at 8° elevation. Observations from 2009 through 2014 were used to derive the nightly averaged seasonal variation of the 95-km altitude meridional wind velocity, as well as the seasonally averaged variation of the meridional wind with local solar time. The results indicate a seasonal trend in which the winds at 95 km are directed southward at about 10 m s[superscript −1] in the summer of the Northern Hemisphere and northward at about 10 m s[superscript −1] in the winter. Nighttime data from −5 to +5 local solar time show a gradual transition of the meridional wind velocity from about −20 to 20 m s[superscript −1]. These variations correlate well with nighttime wind measurements using 557.7-nm optical airglow observations from the Millstone Hill high-resolution Fábry–Perot interferometer (FPI) in Westford.National Science Foundation (U.S.) Research Experiences for Undergraduates (Grant AST-1156504