180 research outputs found

    Chemoembolization versus radioembolization for the treatment of unresectable intrahepatic cholangiocarcinoma in a single institution image-based efficacy and comparative toxicity

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    Aim: Compare radioembolization (Y90) and chemoembolization (CE) for the treatment of unresectable intrahepatic cholangiocarcinoma (UICC). Materials & methods: Institutional Review Board-approved, retrospective search was performed. Forty patients with UICC were treated with either Y90 (n = 25, 39 treatments) or CE (n = 15, 35 treatments). Comparative analysis was performed using Student\u27s Results: Median ages were 60 and 64 years for CE and Y90 groups, respectively (p = 0.798). Patient variables including age, Eastern Cooperative Oncology Group score, tumor burden, extra-hepatic disease, prior chemotherapy and prior surgery were similar between groups. Adverse events were similar in both groups (CE 20%, Y90 26%; p \u3e 0.9). Overall response rate (CE 6%, Y90 4%; p \u3e 0.9) and disease control rate (CE 46%, Y90 48%; p \u3e 0.9) were statistically similar. Multilogistic regression did not identify any variables that correlated with disease control rate, including Eastern Cooperative Oncology Group score and tumor burden. Conclusion: Our observation shows that CE and Y90 display similar toxicity and disease control in the treatment of UICC

    Electrochemical polymerization of pyrene derivatives on functionalized carbon nanotubes for pseudocapacitive electrodes

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    Electrochemical energy-storage devices have the potential to be clean and efficient, but their current cost and performance limit their use in numerous transportation and stationary applications. Many organic molecules are abundant, economical and electrochemically active; if selected correctly and rationally designed, these organic molecules offer a promising route to expand the applications of these energy-storage devices. In this study, polycyclic aromatic hydrocarbons are introduced within a functionalized few-walled carbon nanotube matrix to develop high-energy, high-power positive electrodes for pseudocapacitor applications. The reduction potential and capacity of various polycyclic aromatic hydrocarbons are correlated with their interaction with the functionalized few-walled carbon nanotube matrix, chemical configuration and electronic structure. These findings provide rational design criteria for nanostructured organic electrodes. When combined with lithium negative electrodes, these nanostructured organic electrodes exhibit energy densities of ~350 Wh kg[−1 over electrode] at power densities of ~10 kW kg[−1 over electrode] for over 10,000 cycles.National Science Foundation (U.S.). Graduate Research Fellowship (Grant 1122374)National Science Foundation (U.S.). Materials Research Science and Engineering Centers (Program) (Award DMR-0819762

    Copper(0)-mediated radical polymerisation in a self-generating biphasic system

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    Herein, we demonstrate the synthesis of well-defined poly(n-alkyl acrylate)s via copper(0)-mediated radical polymerisation in a self-generating biphasic system. During the polymerisation of n-butyl acrylate in DMSO, the polymer phase separates to yield a polymer-rich layer with very low copper content (ICP-MS analysis: 0.016 wt%). The poly(n-butyl acrylate) has been characterized by a range of techniques, including GPC, NMR and MALDI-TOF, to confirm both the controlled character of the polymerisation and the end group fidelity. Moreover, we have successfully chain extended poly(n-butyl acrylate) in this biphasic system several times with n-butyl acrylate to high conversion without intermediate purification steps. A range of other alkyl acrylates have been investigated and the control over the polymerisation is lost as the hydrophobicity of the polymer increases due to the increase in alkyl chain length indicating that it is important for the monomer to be soluble in the polar solvent

    The Quiescent Intracluster Medium in the Core of the Perseus Cluster

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    Clusters of galaxies are the most massive gravitationally-bound objects in the Universe and are still forming. They are thus important probes of cosmological parameters and a host of astrophysical processes. Knowledge of the dynamics of the pervasive hot gas, which dominates in mass over stars in a cluster, is a crucial missing ingredient. It can enable new insights into mechanical energy injection by the central supermassive black hole and the use of hydrostatic equilibrium for the determination of cluster masses. X-rays from the core of the Perseus cluster are emitted by the 50 million K diffuse hot plasma filling its gravitational potential well. The Active Galactic Nucleus of the central galaxy NGC1275 is pumping jetted energy into the surrounding intracluster medium, creating buoyant bubbles filled with relativistic plasma. These likely induce motions in the intracluster medium and heat the inner gas preventing runaway radiative cooling; a process known as Active Galactic Nucleus Feedback. Here we report on Hitomi X-ray observations of the Perseus cluster core, which reveal a remarkably quiescent atmosphere where the gas has a line-of-sight velocity dispersion of 164+/-10 km/s in a region 30-60 kpc from the central nucleus. A gradient in the line-of-sight velocity of 150+/-70 km/s is found across the 60 kpc image of the cluster core. Turbulent pressure support in the gas is 4% or less of the thermodynamic pressure, with large scale shear at most doubling that estimate. We infer that total cluster masses determined from hydrostatic equilibrium in the central regions need little correction for turbulent pressure.Comment: 31 pages, 11 Figs, published in Nature July

    The contribution of refractoriness to arrhythmic substrate in hypokalemic Langendorff-perfused murine hearts

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    The clinical effects of hypokalemia including action potential prolongation and arrhythmogenicity suppressible by lidocaine were reproduced in hypokalemic (3.0 mM K(+)) Langendorff-perfused murine hearts before and after exposure to lidocaine (10 μM). Novel limiting criteria for local and transmural, epicardial, and endocardial re-excitation involving action potential duration (at 90% repolarization, APD(90)), ventricular effective refractory period (VERP), and transmural conduction time (Δlatency), where appropriate, were applied to normokalemic (5.2 mM K(+)) and hypokalemic hearts. Hypokalemia increased epicardial APD(90) from 46.6 ± 1.2 to 53.1 ± 0.7 ms yet decreased epicardial VERP from 41 ± 4 to 29 ± 1 ms, left endocardial APD(90) unchanged (58.2 ± 3.7 to 56.9 ± 4.0 ms) yet decreased endocardial VERP from 48 ± 4 to 29 ± 2 ms, and left Δlatency unchanged (1.6 ± 1.4 to 1.1 ± 1.1 ms; eight normokalemic and five hypokalemic hearts). These findings precisely matched computational predictions based on previous reports of altered ion channel gating and membrane hyperpolarization. Hypokalemia thus shifted all re-excitation criteria in the positive direction. In contrast, hypokalemia spared epicardial APD(90) (54.8 ± 2.7 to 60.6 ± 2.7 ms), epicardial VERP (84 ± 5 to 81 ± 7 ms), endocardial APD(90) (56.6 ± 4.2 to 63.7 ± 6.4 ms), endocardial VERP (80 ± 2 to 84 ± 4 ms), and Δlatency (12.5 ± 6.2 to 7.6 ± 3.4 ms; five hearts in each case) in lidocaine-treated hearts. Exposure to lidocaine thus consistently shifted all re-excitation criteria in the negative direction, again precisely agreeing with the arrhythmogenic findings. In contrast, established analyses invoking transmural dispersion of repolarization failed to account for any of these findings. We thus establish novel, more general, criteria predictive of arrhythmogenicity that may be particularly useful where APD(90) might diverge sharply from VERP

    Reading and Ownership

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    First paragraph: ‘It is as easy to make sweeping statements about reading tastes as to indict a nation, and as pointless.’ This jocular remark by a librarian made in the Times in 1952 sums up the dangers and difficulties of writing the history of reading. As a field of study in the humanities it is still in its infancy and encompasses a range of different methodologies and theoretical approaches. Historians of reading are not solely interested in what people read, but also turn their attention to the why, where and how of the reading experience. Reading can be solitary, silent, secret, surreptitious; it can be oral, educative, enforced, or assertive of a collective identity. For what purposes are individuals reading? How do they actually use books and other textual material? What are the physical environments and spaces of reading? What social, educational, technological, commercial, legal, or ideological contexts underpin reading practices? Finding answers to these questions is compounded by the difficulty of locating and interpreting evidence. As Mary Hammond points out, ‘most reading acts in history remain unrecorded, unmarked or forgotten’. Available sources are wide but inchoate: diaries, letters and autobiographies; personal and oral testimonies; marginalia; and records of societies and reading groups all lend themselves more to the case-study approach than the historical survey. Statistics offer analysable data but have the effect of producing identikits rather than actual human beings. The twenty-first century affords further possibilities, and challenges, with its traces of digital reader activity, but the map is ever-changing

    Schoolbooks and textbook publishing.

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    In this chapter the author looks at the history of schoolbooks and textbook publishing. The nineteenth century saw a rise in the school book market in Britain due to the rise of formal schooling and public examinations. Although the 1870 Education and 1872 (Scotland) Education Acts made elementary education compulsory for childern between 5-13 years old, it was not until the end of the First World War that some sort form of secondary education became compulsory for all children

    Hitomi (ASTRO-H) X-ray Astronomy Satellite

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    The Hitomi (ASTRO-H) mission is the sixth Japanese x-ray astronomy satellite developed by a large international collaboration, including Japan, USA, Canada, and Europe. The mission aimed to provide the highest energy resolution ever achieved at E  >  2  keV, using a microcalorimeter instrument, and to cover a wide energy range spanning four decades in energy from soft x-rays to gamma rays. After a successful launch on February 17, 2016, the spacecraft lost its function on March 26, 2016, but the commissioning phase for about a month provided valuable information on the onboard instruments and the spacecraft system, including astrophysical results obtained from first light observations. The paper describes the Hitomi (ASTRO-H) mission, its capabilities, the initial operation, and the instruments/spacecraft performances confirmed during the commissioning operations for about a month
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