1,405 research outputs found

    Determination of demagnetizing factors using first-order reversal curves and ferromagnetic resonance

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    We present a method to quantitatively analyze magnetizing or demagnetizing interactions in arrayed nano-magnets by combining first-order reversal curve (FORC) and ferromagnetic resonance (FMR) measurement data. We develop a function to predict the resulting FORC distribution given: (1) a Gaussian intrinsic distribution in terms of the internal field and (2) a mean interaction field proportional to the sample\u27s magnetic moment. We then perform least-squares regression of our model on experimental FORC measurements of a nanowire array and of a thin film. Combining the obtained interaction field with an FMR fit result allows us to algebraically solve for the effective axial and transverse demagnetizing factors. Our experimental demagnetizing factors agree with expected values and provide quantitative evidence of the demagnetizing interaction between nanowires in an array

    Butt-joint bonding of timber as a key technology for point-supported, biaxial load bearing flat slabs made of cross-laminated timber

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    An efficient butt-joint bonding technology allows to build new types of timber structures. Under the name Timber Structures 3.0 a connection has been developed which connects timber elements with an end-grain to end-grain butt joint bonding. Therefore, it is now possible to build continuous, point supported flat slabs in cross laminated timber (CLT). Multiple CLT slabs are connected rigidly together and are only supported by columns. Some major challenges had to be solved in terms of bending strength of the glued connection and shear resistance of the part of the slab above the column. The research in both topics is successful and more projects were built in the last two years using this technology. Starting point was a real scale structure at ETH Zurich, followed by a working platform for a timber construction company and finally four three storey residential buildings. The research team is continuing to optimize the different elements of this innovative technology and will soon provide engineers with guidelines to design their own biaxial, point supported timber flat slabs

    CT angiography, MR angiography and rotational digital subtraction angiography for volumetric assessment of intracranial aneurysms. An experimental study

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    The purpose of our experimental study was to assess the accuracy and precision of CT angiography (CTA), MR angiography (MRA) and rotational digital subtraction angiography (DSA) for measuring the volume of an in vitro aneurysm model. A rigid model of the anterior cerebral circulation harbouring an anterior communicating aneurysm was connected to a pulsatile circuit. It was studied using unenhanced 3D time-of-flight MRA, contrast-enhanced CTA and rotational DSA angiography. The source images were then postprocessed on dedicated workstations to calculate the volume of the aneurysm. CTA was more accurate than MRA (P=0.0019). Rotational DSA was more accurate than CTA, although the difference did not reach statistical significance (P=0.1605), and significantly more accurate than MRA (P<0.00001). CTA was more precise than MRA (P=0.12), although this did not reach statistical significance. Rotational DSA can be part of the diagnosis, treatment planning and support endovascular treatment of intracranial aneurysms. The emerging endovascular treatment techniques which consist of using liquid polymers as implants to exclude aneurysms from arterial circulation would certainly benefit from this precise measurement of the volume of aneurysm

    Jeder soll besteuert werden, aber nur einmal. 1923 begann in Genf eine weltweite Steuerrevolution

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    Vor hundert Jahren wurde in Genf der Grundstein gelegt zur Besteuerung internationaler Unternehmen – doch der Gründergeist ist heute verflogen

    Subpixel heterogeneity of ice-wedge polygonal tundra: a multi-scale analysis of land cover and evapotranspiration in the Lena River Delta, Siberia

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    Ignoring small-scale heterogeneities in Arctic land cover may bias estimates of water, heat and carbon fluxes in large-scale climate and ecosystem models. We investigated subpixel-scale heterogeneity in CHRIS/PROBA and Landsat-7 ETM satellite imagery over ice-wedge polygonal tundra in the Lena Delta of Siberia, and the associated implications for evapotranspiration (ET) estimation. Field measurements were combined with aerial and satellite data to link fine-scale (0.3m resolution) with coarse-scale (upto 30m resolution) land cover data. A large portion of the total wet tundra (80%) and water body area (30%) appeared in the form of patches less than 0.1 ha in size, which could not be resolved with satellite data. Wet tundra and small water bodies represented about half of the total ET in summer. Their contribution was reduced to 20% in fall, during which ET rates from dry tundra were highest instead. Inclusion of subpixel-scale water bodies increased the total water surface area of the Lena Delta from 13% to 20%. The actual land/water proportions within each composite satellite pixel was best captured with Landsat data using a statistical downscaling approach, which is recommended for reliable large-scale modelling of water, heat and carbon exchange from permafrost landscapes

    Cellulose acetate phthalate, a common pharmaceutical excipient, inactivates HIV-1 and blocks the coreceptor binding site on the virus envelope glycoprotein gp120

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    BACKGROUND: Cellulose acetate phthalate (CAP), a pharmaceutical excipient used for enteric film coating of capsules and tablets, was shown to inhibit infection by the human immunodeficiency virus type 1 (HIV-1) and several herpesviruses. CAP formulations inactivated HIV-1, herpesvirus types 1 (HSV-1) and 2 (HSV-2) and the major nonviral sexually transmitted disease (STD) pathogens and were effective in animal models for vaginal infection by HSV-2 and simian immunodeficiency virus. METHODS: Enzyme-linked immunoassays and flow cytometry were used to demonstrate CAP binding to HIV-1 and to define the binding site on the virus envelope. RESULTS: 1) CAP binds to HIV-1 virus particles and to the envelope glycoprotein gp120; 2) this leads to blockade of the gp120 V3 loop and other gp120 sites resulting in diminished reactivity with HIV-1 coreceptors CXCR4 and CCR5; 3) CAP binding to HIV-1 virions impairs their infectivity; 4) these findings apply to both HIV-1 IIIB, an X4 virus, and HIV-1 BaL, an R5 virus. CONCLUSIONS: These results provide support for consideration of CAP as a topical microbicide of choice for prevention of STDs, including HIV-1 infection

    Między wykluczeniem a aktywizacją społeczną: studia socjologiczne

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    Praca recenzowana / Peer-reviewed paperPrezentowana publikacja stanowi zbiór testów poświęconych wykluczeniu i aktywizacji społecznej ujmowanych w szerokiej perspektywie poznawczej. Mimo iż najczęściej problematyka ta poruszana jest na gruncie socjologii, złożoność zjawiska, jego przejawy, formy i sposoby zapobiegania sprowokowały grono badaczy do podjęcia interdyscyplinarnej dyskusji. Stąd też prezentowany tom jest zbiorem tekstów przygotowanych przez specjalistów i badaczy reprezentujących różne dziedziny nauki – socjologów, pedagogów oraz specjalistów z zakresu zarządzania. O tym, jak ten dynamiczny proces wielowymiarowego pękania „więzi społecznych” na poziomie indywidualnym i zbiorowym definiować, jak zapobiegać wykluczeniu z uczestnictwa w systemie normatywnym danego społeczeństwa, dostępie do informacji i zasobów społecznych rozmawiano podczas spotkania konferencyjnego zorganizowanego w czerwcu 2015 roku przez Krakowską Akademię im. Andrzeja Frycza Modrzewskiego w ramach panelu Państwo, Gospodarka, Społeczeństwo. Zapoczątkowana w trakcie obrad dyskusja sprowokowała do podjęcia starań o wydanie tomu, w którym udałoby się utrwalić ważność podjętych tematów i zachęcić do otwarcia szerszej interdyscyplinarnej dyskusji

    Anticancer Gene Transfer for Cancer Gene Therapy

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    Gene therapy vectors are among the treatments currently used to treat malignant tumors. Gene therapy vectors use a specific therapeutic transgene that causes death in cancer cells. In early attempts at gene therapy, therapeutic transgenes were driven by non-specific vectors which induced toxicity to normal cells in addition to the cancer cells. Recently, novel cancer specific viral vectors have been developed that target cancer cells leaving normal cells unharmed. Here we review such cancer specific gene therapy systems currently used in the treatment of cancer and discuss the major challenges and future directions in this field
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