Tunable single-mode coupled-cavity laser in a standard InP photonics platform

We present a wavelength tunable, coupled-cavity laser in a standard indium phosphide multiproject wafer shuttle which did not support distributed feedback gratings. The single-mode operation was enabled by reflections from slots in the laser cavity. The wavelength of the laser emission was tunable over 20 nm near a wavelength of 1560 nm via the currents applied to each section of the laser. A maximum side-mode suppression ratio of 46 dB was observed. The delayed self-heterodyne spectrum of the laser showed a Voigt line shape, corresponding to optical linewidths of 3.7 MHz for the Lorentzian and 88 MHz for the Gaussian contributions

C-type lectin Langerin is a beta-glucan receptor on human Langerhans cells that recognizes opportunistic and pathogenic fungi

Langerhans cells (LCs) lining the stratified epithelia and mucosal tissues are the first antigen presenting cells to encounter invading pathogens, such as viruses, bacteria and fungi. Fungal infections form a health threat especially in immuno-compromised individuals. LCs express C-type lectin Langerin that has specificity for mannose, fucose and GlcNAc structures. Little is known about the role of human Langerin in fungal infections. Our data show that Langerin interacts with both mannan and p-glucan structures, common cell-wall carbohydrate structures of fungi. We have screened a large panel of fungi for recognition by human Langerin and, strikingly, we observed strong binding of Langerin to a variety of Candida and Saccharomyces species and Malassezia furfur, but very weak binding was observed to Cryptococcus gattii and Cryptococcus neoformans. Notably, Langerin is the primary fungal receptor on LCs, since the interaction of LCs with the different fungi was blocked by antibodies against Langerin. Langerin recognizes both mannose and beta-glucans present on fungal cell walls and our data demonstrate that Langerin is the major fungal pathogen receptor on human LCs that recognizes pathogenic and commensal fungi. Together these data may provide more insight in the role of LCs in fungal infections. (C) 2009 Elsevier Ltd. All rights reserved

A Meta‐Analysis on the Effects of Text Structure Instruction on Reading Comprehension in the Upper Elementary Grades

In this meta‐analysis, the authors synthesize results from 44 (quasi‐)experimental studies on informational and narrative text structure interventions involving students in grades 4–6 in regular school settings. Findings show that text structure instruction had positive immediate effects on students’ reading comprehension but that effect sizes varied largely across outcome measures: questions (Hedges’ g = 0.25), summarization (g = 0.57), recall (g = 0.37), and knowledge about text structure (g = 0.38). However, students who received text structure instruction no longer outperformed control groups at delayed posttests. Content‐related features, such as a focus on paragraph‐level structure, active construction of graphic organizers, and teaching rule‐based summarization techniques, moderated the effectiveness of text structure instruction, but these effects also varied across outcome measures. Instructional features moderated delayed effects: Interventions with opportunities for individual student practice resulted in higher delayed effects for comprehension questions. The authors argue that text structure instruction deserves a place in the primary school curriculum so the positive effects on reading will be maintained