905 research outputs found

    Being Blacklisted by China, And What Can Be Learned from It

    Get PDF
    Bloomberg, and more recently The Washington Post, have run stories about the visa problems of scholars who contributed to Xinjiang: China’s Muslim Borderland, a volume edited by Frederick Starr and published by M.E. Sharpe in 2004. The Bloomberg piece was exhaustively reported; the reporters who wrote it, Dan Golden and Oliver Staley, conducted interviews with Chinese as well as western participants in the episode, and all in all did a good job with a complicated story. Inevitably, however, the Bloomberg piece creates some misconceptions, and these are as likely to be reinforced as cleared up in news reports that build on it, as the Washington Post story of last weekend shows. Now seems the time both to correct the problematic aspects of the Bloomberg piece and also to discuss lessons we may take away from the entire episode. There are a couple of key issues involved. Of special importance to scholars of China: are you in danger of being banned for what you write? My answer below will be, “not really.” And for universities, grant agencies and other institutions involved in academic exchanges with China, the episode raises the question of what you should do in the face of official Chinese interference in curriculum, research, guest lectures or other academic matters. I will suggest that a strong and collective response, organized by institutions and not left to the affected scholars themselves, is imperative. The reason for such a response is not simply to help individual scholars get visas, but to make the point that academic exchange must be unhampered and reciprocal and to set the right tone for future academic interchange with China

    Minimally invasive management of vital teeth requiring root canal therapy

    Get PDF
    The present study aimed to investigate the possible use of a non-instrumentation technique including blue light irradiation for root canal cleaning. Extracted human single rooted teeth were selected. Nine different groups included distilled water, NaOCl, intra-canal heated NaOCl, and NaOCl + EDTA irrigation after either instrumentation or non-instrumentation, and a laser application group following non-instrumentation technique. The chemical assessment of the root canal dentine was evaluated using EDS and FT-IR. Surface microstructural analyses were performed by using SEM. The antimicrobial efficacy of different preparation techniques was evaluated using microbial tests. Laser application didn’t change the Ca/P, carbonate/phosphate and amide I/phosphate ratios of the root canal dentin the root canal dentin preserved its original form after light application. The instrumentation decreased the carbonate/phosphate and amide I/phosphate ratios of the root canal dentin regardless of the irrigation solution or technique (p < 0.05). According to the microbiological tests, the light application could not provide antibacterial efficacy as much as NaOCl irrigation. The NaOCl irrigation both in the non-instrumentation and instrumentation groups significantly reduced the number of bacteria (p < 0,05). Minimally invasive root canal preparation techniques where the root canal is not instrumented and is disinfected by laser irradiation followed by obturation with a hydraulic cement sealer may be an attractive treatment option for management of vital teeth needing root canal therapy and does not have any detrimental effects on the chemical structure of dentin

    Gene co-expression networks shed light into diseases of brain iron accumulation

    Get PDF
    Aberrant brain iron deposition is observed in both common and rare neurodegenerative disorders, including those categorized as Neurodegeneration with Brain Iron Accumulation (NBIA), which are characterized by focal iron accumulation in the basal ganglia. Two NBIA genes are directly involved in iron metabolism, but whether other NBIA-related genes also regulate iron homeostasis in the human brain, and whether aberrant iron deposition contributes to neurodegenerative processes remains largely unknown. This study aims to expand our understanding of these iron overload diseases and identify relationships between known NBIA genes and their main interacting partners by using a systems biology approach. We used whole-transcriptome gene expression data from human brain samples originating from 101 neuropathologically normal individuals (10 brain regions) to generate weighted gene co-expression networks and cluster the 10 known NBIA genes in an unsupervised manner. We investigated NBIA-enriched networks for relevant cell types and pathways, and whether they are disrupted by iron loading in NBIA diseased tissue and in an in vivo mouse model. We identified two basal ganglia gene co-expression modules significantly enriched for NBIA genes, which resemble neuronal and oligodendrocytic signatures. These NBIA gene networks are enriched for iron-related genes, and implicate synapse and lipid metabolism related pathways. Our data also indicates that these networks are disrupted by excessive brain iron loading. We identified multiple cell types in the origin of NBIA disorders. We also found unforeseen links between NBIA networks and iron-related processes, and demonstrate convergent pathways connecting NBIAs and phenotypically overlapping diseases. Our results are of further relevance for these diseases by providing candidates for new causative genes and possible points for therapeutic intervention

    Sliding charge density wave in manganites

    Full text link
    The so-called stripe phase of the manganites is an important example of the complex behaviour of metal oxides, and has long been interpreted as the localisation of charge at atomic sites. Here, we demonstrate via resistance measurements on La_{0.50}Ca_{0.50}MnO_3 that this state is in fact a prototypical charge density wave (CDW) which undergoes collective transport. Dramatic resistance hysteresis effects and broadband noise properties are observed, both of which are typical of sliding CDW systems. Moreover, the high levels of disorder typical of manganites result in behaviour similar to that of well-known disordered CDW materials. Our discovery that the manganite superstructure is a CDW shows that unusual transport and structural properties do not require exotic physics, but can emerge when a well-understood phase (the CDW) coexists with disorder.Comment: 13 pages; 4 figure

    Progress in the Development of the 1 m Model of the 70 mm Aperture Quadrupole for the LHC Low-ÎČ\beta Insertions

    Get PDF
    Within the LHC magnet development program Oxford Instruments has built a one metre model of the 70 mm aperture low-beta quadrupole. The magnet features a four layer coil wound from two 8.2 mm wide graded NbTi cables, and is designed for 250 T/m at 1.9 K. The magnet has previously been tested between 4.5 K and 2.3 K. In this paper we review the magnet rebuild and the subsequent tests. Results on magnet training at 4.3 K and 1.9 K are presented along with the results related to quench protection studies.
    • 

    corecore