Conjugated Polymers Combined with a Molecular Beacon for Label-Free and Self-Signal-Amplifying DNA Microarrays

A conjugated polymer (CP) and molecular-beacon-based solid-state DNA sensing system is developed to achieve sensitive, label-free detection. A novel conjugated poly(oxadiazole) derivative exhibiting amine and thiol functional groups ( POX-SH ) is developed for unique chemical and photochemical stability and convenient solid-state on-chip DNA synthesis. POX-SH is soluble in most nonpolar organic solvents and exhibits intense blue fluorescence. POX-SH is covalently immobilized onto a maleimido-functionalized glass slide by means of its thiol group. Molecular beacons having a fluorescent dye or quencher molecule as the fluorescence resonance energy transfer (FRET) acceptor are synthesized on the immobilized POX-SH layer through direct on-chip oligonucleotide synthesis using the amine side chain of POX-SH . Selective hybridization of the molecular beacon probes with the target DNA sequence opens up the molecular beacon probes and affects the FRET between POX-SH and the dye or quencher, producing a sensitive and label-free fluorescence sensory signal. Various molecular design parameters, such as the size of the stem and loop of the molecular beacon, the choice of dye, and the number of quencher molecules are systematically controlled, and their effects on the sensitivity and selectivity are investigated.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/64307/1/3317_ftp.pd

Suppression of magnetic ordering in XXZ-type antiferromagnetic monolayer NiPS3

How a certain ground state of complex physical systems emerges, especially in two-dimensional materials, is a fundamental question in condensed-matter physics. A particularly interesting case is systems belonging to the class of XY Hamiltonian where the magnetic order parameter of conventional nature is unstable in two-dimensional materials leading to a Berezinskii-Kosterlitz-Thouless transition. Here, we report how the XXZ-type antiferromagnetic order of a magnetic van der Waals material, NiPS3, behaves upon reducing the thickness and ultimately becomes unstable in the monolayer limit. Our experimental data are consistent with the findings based on renormalization group theory that at low temperatures a two-dimensional XXZ system behaves like a two-dimensional XY one, which cannot have a long-range order at finite temperatures. This work provides experimental examination of the XY magnetism in the atomically thin limit and opens new opportunities of exploiting these fundamental theorems of magnetism using magnetic van der Waals materials.Comment: 57 pages, 24 figures (including Supplementary Information

A Survey of Music Teachers’ Working Conditions

For this study the researchers examined music teacher responses to survey items pertaining to their working conditions. Participants reported their satisfaction about factors related to music program funding, facilities, workload, professional development, and school culture. Responses were analyzed to detect possible differences in responses due to demographic factors of teachers, schools, and teaching assignments. Initial findings indicated that teachers were generally satisfied with their all aspects of their working conditions with the exception of professional development. A MANOVA was conducted to determine if there were any significant differences in responses based on participant demographics. While our study found no disparities in working conditions due to teacher factors, we did find a statistically significant link between the socioeconomic status of the school community and teacher perceptions of the funding, facilities, and culture within the school. This relationship was found to be moderated by the locale of the school, with greater differences in working conditions between low and high socioeconomically situated music programs in suburban and urban communities compared to their more rural peers. Open-ended responses from participants suggested that while disparities exist between music programs, teachers may judge their working conditions in comparison to their perceptions about other schools rather than the realities

Bone regeneration via novel macroporous CPC scaffolds in critical-sized cranial defects in rats

Objectives. Calcium phosphate cement (CPC) is promising for dental and craniofacial applications due to its ability to be injected or filled into complex-shaped bone defects and molded for esthetics, and its resorbability and replacement by new bone. The objective of this study was to investigate bone regeneration via novel macroporous CPC containing absorbable fibers, hydrogel microbeads and growth factors in critical-sized cranial defects in rats. Methods. Mannitol porogen and alginate hydrogel microbeads were incorporated into CPC. Absorbable fibers were used to provide mechanical reinforcement to CPC scaffolds. Six CPC groups were tested in rats: (1) control CPC without macropores and microbeads; (2) macroporous CPC + large fiber; (3) macroporous CPC + large fiber + nanofiber; (4) same as (3), but with rhBMP2 in CPC matrix; (5) same as (3), but with rhBMP2 in CPC matrix + rhTGF-beta 1 in microbeads; (6) same as (3), but with rhBMP2 in CPC matrix + VEGF in microbeads. Rats were sacrificed at 4 and 24 weeks for histological and micro-CT analyses. Results. The macroporous CPC scaffolds containing porogen, absorbable fibers and hydrogel microbeads had mechanical properties similar to cancellous bone. At 4 weeks, the new bone area fraction (mean +/- sd; n = 5) in CPC control group was the lowest at (14.8 +/- 3.3)%, and that of group 6 (rhBMP2 + VEGF) was (31.0 +/- 13.8)% (p < 0.05). At 24 weeks, group 4 (rhBMP2) had the most new bone of (38.8 +/- 15.6)%, higher than (12.7 +/- 5.3)% of CPC control (p < 0.05). Micro-CT revealed nearly complete bridging of the critical-sized defects with new bone for several macroporous CPC groups, compared to much less new bone formation for CPC control. Significance. Macroporous CPC scaffolds containing porogen, fibers and microbeads with growth factors were investigated in rat cranial defects for the first time. Macroporous CPCs had new bone up to 2-fold that of traditional CPC control at 4 weeks, and 3-fold that of traditional CPC at 24 weeks, and hence may be useful for dental, craniofacial and orthopedic applications. (C) 2014 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved

Acute Hemorrhagic Conjunctivitis caused by Coxsackievirus A24 Variant, South Korea, 2002

In summer 2002, a nationwide outbreak of acute hemorrhagic conjunctivitis occurred in South Korea. The etiologic agent was confirmed as coxsackievirus A24 variant (CA24v) by virus isolation and sequencing of a part of the VP1 gene. Phylogentic analysis, based on the protease 3C sequences, showed that the Korean isolates were clustered into a lineage distinct from the CA24v isolates reported in previous outbreaks in Asia