3,367 research outputs found

    #Socialtagging: Defining its Role in the Academic Library

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    The information environment is rapidly changing, affecting the ways in which information is organized and accessed. User needs and expectations have also changed due to the overwhelming influence of Web 2.0 tools. Conventional information systems no longer support evolving user needs. Based on current research, we explore a method that integrates the structure of controlled languages with the flexibility and adaptability of social tagging. This article discusses the current research and usage of social tagging and Web 2.0 applications within the academic library. Types of tags, the semiotics of tagging and its influence on indexing are covered

    Chronic morphine treatment attenuates cell growth of human BT474 breast cancer cells by rearrangement of the ErbB signalling network.

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    There is increasing evidence that opioid analgesics may interfere with tumour growth. It is currently thought that these effects are mediated by transactivation of receptor tyrosine kinase (RTK)-controlled ERK1/2 and Akt signalling. The growth of many breast cancer cells is dependent on hyperactive ErbB receptor networks and one of the most successful approaches in antineoplastic therapy during the last decade was the development of ErbB-targeted therapies. However, the response rates of single therapies are often poor and resistance mechanisms evolve rapidly. To date there is no information about the ability of opioid analgesics to interfere with the growth of ErbB-driven cancers. Here we demonstrate that ErbB2 overexpressing BT474 human breast cancer cells carry fully functional endogenous µ-opioid receptors. Most interestingly, the acute opioid effects on basal and Heregulin-stimulated ERK1/2 and Akt phosphorylation changed considerably during chronic Morphine treatment. Investigation of the underlying mechanism by the use of protein kinase inhibitors and co-immunoprecipitation studies revealed that chronic Morphine treatment results in rearrangement of the ErbB signalling network leading to dissociation of ERK1/2 from Akt signalling and a switch from ErbB1/ErbB3 to ErbB1/ErbB2-dependent cell growth. In chronically Morphine-treated cells Heregulin-stimulated ERK1/2 signalling is redirected via a newly established PI3K- and metalloproteinase-dependent feedback loop. Together, these alterations result in apoptosis of BT474 cells. A similar switch in Heregulin-stimulated ERK1/2 signalling from an ErbB2-independent to an ErbB2-, PI3K- and metalloproteinase-dependent mechanism was also observed in κ-opioid receptor expressing SKBR3 human mammary adenocarcinoma cells. The present data demonstrate that the ErbB receptor network of human breast cancer cells represents a target for chronic Morphine treatment. Rearrangement of ErbB signalling by chronic Morphine may provide a promising strategy to enhance the sensitivity of breast cancer cells to ErbB-directed therapies and to prevent the development of escape mechanisms

    Analysis and documentation of QCSEE (Quiet Clean Short-haul Experimental Engine) over-the-wing exhaust system development

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    A static scale model test program was conducted in the static test area of the NASA-Langley 9.14- by 18.29 m(30- by 60-ft) Full-Scale Wind Tunnel Facility to develop an over-the-wing (OTW) nozzle and reverser configuration for the Quiet Clean Short-Haul Experimental Engine (QCSEE). Three nozzles and one basic reverser configuration were tested over the QCSEE takeoff and approach power nozzle pressure ratio range between 1.1 and 1.3. The models were scaled to 8.53% of QCSEE engine size and tested behind two 13.97-cm (5.5-in.) diameter tip-turbine-driven fan simulators coupled in tandem. An OTW nozzle and reverser configuration was identified which satisfies the QCSEE experimental engine requirements in terms of nozzle cycle area variation capability and reverse thrust level, and provides good jet flow spreading over a wing upper surface for achievement of high propulsive lift performance

    ANALISIS FAKTOR-FAKTOR YANG MEMPENGARUHI CADANGAN DEVISA INDONESIA PERIODE 1999-2013

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    ABSTRAK Perekonomian Indonesia saat ini sudah tidak dapat terpisahkan lagi dengan perekonomian dunia. Hal ini terjadi setelah dianutnya sistem perekonomian terbuka yang dalam aktivitasnya selalu berhubungan dan tidak lepas dari fenomena hubungan internasional. Adanya keterbukaan perekonomian ini berdampak pada perkembangan neraca pembayaran suatu negara yang meliputi arus perdagangan dan lalu lintas modal luar negeri suatu negara. Salah satu bentuk aliran modal yang masuk ke dalam negeri yaitu dapat berupa devisa yang berasal dari perdagangan internasional yang dilakukan oleh negara tersebut. Meningkatnya ekspor suatu negara akan membawa keuntungan yaitu kenaikan pendapatan, kenaikan devisa, transfer modal dan makin banyaknya kesempatan kerja. Penelitian ini bertujuan untuk mengkaji sejauh mana variabel-variabel bebas seperti laju pertumbuhan ekonomi, kurs, utang luar negeri dan ekspor berpengaruh terhadap cadangan devisa Indonesia Tahun 1999-2013. Metode analisis yang digunakan adalah Ordinary Least Square (OLS) dengan metode analisis linear berganda diregresi menggunakan E-Views 6. Dalam penelitian ini, dibuktikan dengan uji-F, bahwa variabel laju pertumbuhan ekonomi Indonesia, nilai tukar/kurs, utang luar negeri, dan ekspor secara bersama-sama berpengaruh secara signifikan terhadap cadangan devisa Indonesia. Berdasarkan uji-t, secara parsial, variabel laju pertumbuhan ekonomi Indonesia memiliki hubungan negatif dan tidak signifikan, nilai tukar (kurs) memiliki hubungan negatif dan signifikan terhadap cadangan devisa Indonesia. Utang luar negeri dan ekspor berpengaruh positif dan signifikan terhadap cadangan devisa Indonesia. Kata Kunci : Cadangan Devisa Indonesia, Laju Pertumbuhan Ekonomi, Nilai Tukar (Kurs), Utang Luar Negeri, dan Ekspor

    Look at Me Now: What Attracts U.S. Shareholders?

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    This paper investigates the underlying determinants of home bias using a comprehensive data set on U.S. investors' aggregate holdings of every foreign stock. Among those foreign stocks that are not listed on U.S. exchanges, which account for more than 96 percent of our usable data sample, we find that U.S. investors prefer firms with characteristics associated with greater information transparency, such as stronger home-country accounting standards. We document that a U.S. cross-listing is economically important, as U.S. ownership of a foreign firm roughly doubles upon cross-listing in the United States. We explore the cross-sectional variation in this "cross-listing effect" and find that the increase in U.S. investment is greatest for firms that are from weak accounting backgrounds and are otherwise informationally opaque, suggesting that the key effect of cross-listing is improvements in disclosure that are valued by U.S. investors. By contrast, cross-listing does not increase the appeal of stocks from countries with weak shareholder rights, suggesting that U.S. cross-listing cannot substitute for legal protections in the home country. Nor does the cross-listing effect appear to be driven simply by increased "familiarity"� with the stock or lowered cross-border transactions costs.

    Thrust reverser design studies for an over-the-wing STOL transport

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    Aerodynamic and acoustics analytical studies were conducted to evaluate three thrust reverser designs for potential use on commercial over-the-wing STOL transports. The concepts were: (1) integral D nozzle/target reverser, (2) integral D nozzle/top arc cascade reverser, and (3) post exit target reverser integral with wing. Aerodynamic flowpaths and kinematic arrangements for each concept were established to provide a 50% thrust reversal capability. Analytical aircraft stopping distance/noise trade studies conducted concurrently with flow path design showed that these high efficiency reverser concepts are employed at substantially reduced power settings to meet noise goals of 100 PNdB on a 152.4 m sideline and still meet 609.6 m landing runway length requirements. From an overall installation standpoint, only the integral D nozzle/target reverser concept was found to penalize nacelle cruise performance; for this concept a larger nacelle diameter was required to match engine cycle effective area demand in reverse thrust
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