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- ArticleYoo KH, Cho J, Han B, Kim SH, Shin DY, Hong J, Kim H, Kim HJ, Zang DY, Yoon SS, Jin JY, Lee JH, Hong DS, Park SK.PLoS One. 2020;15(8):e0235503.PURPOSE: We evaluated the outcomes of decitabine as first-line treatment in older patients with acute myeloid leukemia (AML) and investigated the predictors, including a baseline mini nutritional assessment short form (MNA-SF) score, of response and survival.
PATIENTS AND METHODS: Between 2010 and 2018, 96 AML patients aged 65 and above who received decitabine treatment at 6 centers in Korea were retrospectively evaluated. Response rates, hematologic improvements (HI), progression-free survival (PFS), and overall survival (OS) were analyzed.
RESULTS: The median age at diagnosis was 73.9 years, and the median number of decitabine treatments administered to the patients was 4 (range, 1-29). Of 85 patients, 15 patients (17.6%) achieved complete remission (CR) or CR with incomplete blood count recovery. Twelve patients (14.1%) showed partial remission (PR), and 18 (21.2%) demonstrated HI without an objective response. The median PFS and OS were 7.0 (95% confidence interval [CI], 4.9-9.0) and 10.6 (95% CI, 7.7-13.5%) months, respectively. In multivariate analyses, MNA-SF score ≥ 8 and the absence of peripheral blood (PB) blasts were significant predictors for improved PFS and OS.
CONCLUSIONS: For older patients with newly diagnosed AML, a high MNA-SF score and the absence of PB blasts were independently associated with improved survival. - ArticleQu C, Ma S, Hao J, Qiu M, Li X, Xiao S, Miao Z, Dai N, He Q, Sun S, Zhou L.Phys Rev Lett. 2015 Dec 04;115(23):235503.Metasurfaces in a metal-insulator-metal configuration have been widely used in photonics, with applications ranging from perfect absorption to phase modulation, but why and when such structures can realize what functionalities are not yet fully understood. Here, we establish a complete phase diagram in which the optical properties of such systems are fully controlled by two simple parameters (i.e., the intrinsic and radiation losses), which are, in turn, dictated by the geometrical or material properties of the underlying structures. Such a phase diagram can greatly facilitate the design of appropriate metasurfaces with tailored functionalities demonstrated by our experiments and simulations in the terahertz regime. In particular, our experiments show that, through appropriate structural or material tuning, the device can be switched across the phase boundaries yielding dramatic changes in optical responses. Our discoveries lay a solid basis for realizing functional and tunable photonic devices with such structures.
- ArticleSong YQ, Carneiro G, Schwartz LM, Johnson DL.Phys Rev Lett. 2014 Dec 05;113(23):235503.Spin relaxation based nuclear magnetic resonance (NMR) methods have been used extensively to determine pore size distributions in a variety of materials. This approach is based on the assumption that each pore is in the fast diffusion limit but that diffusion between pores can be neglected. However, in complex materials these assumptions may be violated and the relaxation time distribution is not easily interpreted. We present a 2D NMR technique and an associated data analysis that allow us to work directly with the time dependent experimental data without Laplace inversion to identify the signature of diffusive coupling between different pores. Measurements on microporous glass beads and numerical simulations are used to illustrate the technique.
- ArticleBokeloh J, Divinski SV, Reglitz G, Wilde G.Phys Rev Lett. 2011 Dec 02;107(23):235503.Atomic diffusion in deformed Pd(40)Ni(40)P(20) bulk metallic glass containing a single family of deformation-induced shear bands was measured by the radiotracer technique. The significant, by orders of magnitude, enhancement of the diffusion rate with respect to that in the untransformed matrix suggests that the shear bands represent short-circuit diffusion paths. Correlations between diffusivity, viscosity, and the excess free volume distribution inside of shear bands are discussed.
- ArticleFeng W, Meyerheim HL, Mohseni K, Brovko O, Stepanyuk VS, Jedrecy N, Felici R, Kirschner J.Phys Rev Lett. 2013 Jun 07;110(23):235503.The geometry of oxygen atoms in hollow sites of Fe nanoislands (⊘≈1-2 nm) on Fe(001) is modified by mesoscopic misfit-induced relaxations of the island atoms. Surface x-ray diffraction, scanning tunneling microscopy, and ab initio calculations indicate a 0.3 Å increased adsorption height [0.7 Å versus 0.4 Å in O/Fe(001)-p(1×1)] of O atoms going in parallel with a reduced Fe-Fe layer spacing inducing a reduction of the surface magnetic moment (2.85μ(B) versus 3.2μ(B)). Our results demonstrate the importance of the mesoscopic misfit for surface physical properties in general.
- ArticleTeweldeberhan AM, Dubois JL, Bonev SA.Phys Rev Lett. 2010 Dec 03;105(23):235503.The phase diagram of Ca is examined using a combination of density-functional theory (DFT) and diffusion quantum Monte Carlo (DMC) calculations. Gibbs free energies of several competing structures are computed at pressures near 50 GPa. Existing disagreements for the stability of Ca both at low and room temperature are resolved with input from DMC. Furthermore, DMC calculations are performed on 0 K crystalline structures up to 150 GPa and it is demonstrated that the widely used generalized gradient approximation of DFT is insufficient to accurately account for the relative stability of the high-pressure phases of Ca. The results indicate that the theoretical phase diagram of Ca needs a revision.
- ArticleKeys AS, Glotzer SC.Phys Rev Lett. 2007 Dec 07;99(23):235503.Using molecular simulations, we show that the aperiodic growth of quasicrystals is controlled by the ability of the growing quasicrystal nucleus to incorporate kinetically trapped atoms into the solid phase with minimal rearrangement. In the system under investigation, which forms a dodecagonal quasicrystal, we show that this process occurs through the assimilation of stable icosahedral clusters by the growing quasicrystal. Our results demonstrate how local atomic interactions give rise to the long-range aperiodicity of quasicrystals.
- ArticleRodney D, Schuh C.Phys Rev Lett. 2009 Jun 12;102(23):235503.The potential energy landscape of a flowing metallic glass is revealed using the activation-relaxation technique. For a two-dimensional Lennard-Jones system initially deformed into a steady-state condition through quasistatic shear, the distribution of activation energies is shown to contain a large fraction of low-energy barriers, consistent with a highly nonequilibrium flow state. The distribution of plastic strains has a fundamentally different shape than that obtained during quasistatic simulations, exhibiting a peak at finite strain and, after elastic unloading, a nonzero mean plastic strain that evidences a polarization of the flow state. No significant correlation is found between the activation energy of a plastic event and its associated plastic strain.
- ArticleStankov S, Yue YZ, Miglierini M, Sepiol B, Sergueev I, Chumakov AI, Hu L, Svec P, Rüffer R.Phys Rev Lett. 2008 Jun 13;100(23):235503.The vibrational dynamics of nanocrystalline Fe(90)Zr(7)B(3) was studied at various phases of crystallization. The density of phonon states (DOS) of the nanograins was separated from that of the interfaces for a wide range of grain sizes and interface thicknesses. The DOS of the nanograins does not vary with their size and down to 2 nm grains still closely resembles that of the bulk. The anomalous enhancement of the phonon states at low and high energies originates from the DOS of the interfaces and scales linearly to their atomic fraction.
- ArticleJanssen KP, Knez K, Vanysacker L, Schrooten J, Spasic D, Lammertyn J.Nanotechnology. 2012 Jun 15;23(23):235503.Significant research efforts are continually being directed towards the development of sensitive and accurate surface plasmon resonance biosensors for sequence specific DNA detection. These sensors hold great potential for applications in healthcare and diagnostics. However, the performance of these sensors in practical usage scenarios is often limited due to interference from the sample matrix. This work shows how the co-immobilization of glycol(PEG) diluents or 'back filling' of the DNA sensing layer can successfully address these problems. A novel SPR based melting assay is used for the analysis of a synthetic oligomer target as well as PCR amplified genomic DNA extracted from Legionella pneumophila. The benefits of sensing layer back filling on the assay performance are first demonstrated through melting analysis of the oligomer target and it is shown how back filling enables accurate discrimination of Legionella pneumophila serogroups directly from the PCR reaction product with complete suppression of sensor fouling.
- ArticleBaer BJ, Evans WJ, Yoo CS.Phys Rev Lett. 2007 Jun 08;98(23):235503.Coherent anti-Stokes Raman spectroscopy has been used to study deuterium at ambient temperature to 187 GPa, the highest pressure this technique has ever been applied. The pressure dependence of the nu1 vibron line shape indicates that deuterium has a rho direct=0.501 and rho exciton=0.434 mol/cm3 for a band gap of 2omega P=4.66 eV. The extrapolation from the ambient pressure band gap yields a metallization pressure of 460 GPa, confirming earlier measurements. Above 143 GPa, the Raman shift data provide clear evidence for the presence of the ab initio predicted I' phase of deuterium.
- ArticleWrubel JP, Hubbard BE, Agladze NI, Sievers AJ, Fedorov PP, Klimenchenko DI, Ryskin AI, Campbell JA.Phys Rev Lett. 2006 Jun 16;96(23):235503.THz spectroscopy is used to identify a broad distribution of two-level systems, characteristic of glasses, in the substitutional monatomic mixed crystal systems, Ba(1-x)Ca(x)F(2) and Pb(1-x)Ca(x)F(2). In these minimally disordered systems, two-level behavior, which was not previously known to occur, begins at a specific CaF(2) concentration. The concentration dependence, successfully modeled using the statistics of the impurity distribution in the lattice, points to a collective dopant tunneling mechanism.
- ArticleOğüt S, Chelikowsky JR.Phys Rev Lett. 2003 Dec 05;91(23):235503.The atomic and electronic structures of a lattice vacancy trapped next to an As impurity (the E-center defect) in crystalline Si are investigated using ab initio pseudopotential total energy calculations. Jahn-Teller distortions and energies, reorientation barriers, defect wave function characters, and hyperfine coupling parameters associated with (-) and (0) charge states of the E center are calculated using a combination of real-space cluster and plane wave supercell methods. For the first time in the theoretical study of this defect, the senses of the Jahn-Teller distortions in the two charge states are found to be opposite, changing from a large pairing type in (0) to a large resonant-bond type distortion in the (-) charge state, in agreement with experimental data.
- ArticleCraievich AF, Kellermann G, Barbosa LC, Alves OL.Phys Rev Lett. 2002 Dec 02;89(23):235503.A nanocomposite consisting of PbTe nanocrystals embedded in a silicate glass was studied by small-angle x-ray scattering during the early stage of isothermal annealing at 793 K. A theoretical function based on a model of spherical PbTe nanocrystals surrounded by a Pb and Te depleted shell fits well to all experimental curves. The time dependences of the nanocrystal radius and size of the depleted shell agree with the prediction of the theory of nucleation and growth by the classical mechanism of atomic diffusion.
- ArticleReed EJ, Fried LE, Joannopoulos JD.Phys Rev Lett. 2003 Jun 13;90(23):235503.A new multiscale simulation method is formulated for the study of shocked materials. The method combines molecular dynamics and the Euler equations for compressible flow. Treatment of the difficult problem of the spontaneous formation of multiple shock waves due to material instabilities is enabled with this approach. The method allows the molecular dynamics simulation of the system under dynamical shock conditions for orders of magnitude longer time periods than is possible using the popular nonequilibrium molecular dynamics approach. An example calculation is given for a model potential for silicon in which a computational speedup of 10(5) is demonstrated. Results of these simulations are consistent with the recent experimental observation of an anomalously large elastic precursor on the nanosecond time scale.
- ArticleLopatin AV, Vinokur VM.Phys Rev Lett. 2002 Jun 10;88(23):235503.We generalize the Beliaev-Popov diagrammatic technique for the problem of interacting dilute Bose gas with weak disorder. Averaging over disorder is implemented by the replica method. The low-energy asymptotic form of the Green function confirms that the low-energy excitations of the superfluid dirty-boson system are sound waves with velocity renormalized by the disorder and additional dissipation due to the impurity scattering. We find the thermodynamic potential and the superfluid density at any temperature below the superfluid transition temperature (but outside the Ginzburg region) and derive the phase diagram in temperature vs disorder plane.
- ArticleRamesh Babu K, Vaitheeswaran G.J Phys Condens Matter. 2014 Jun 11;26(23):235503.We report a systematic first principles density functional study on the electronic structure, elastic and optical properties of nitrogen based solid hydrogen storage materials LiNH2, NaNH2, KNH2, and RbNH2. The ground state structural properties are calculated by using standard density functional theory, and also dispersion corrected density functional theory. We find that van der Waals interactions are dominant in LiNH2 whereas they are relatively weak in other alkali metal amides. The calculated elastic constants show that all the compounds are mechanically stable and LiNH2 is found to be a stiffer material among the alkali metal amides. The melting temperatures are calculated and follow the order RbNH2 < KNH2 < NaNH2 < LiNH2. The electronic band structure is calculated by using the Tran–Blaha modified Becke–Johnson potential and found that all the compounds are insulators, with a considerable band gap. The [NH2]− derived states completely dominate in the entire valence band region while the metal atom states occupy the conduction band. The calculated band structure is used to analyze the different interband optical transitions occurring between valence and conduction bands. Our calculations show that these materials have considerable optical anisotropy.
- ArticleKumar A, Ganguly A, Papakonstantinou P.J Phys Condens Matter. 2012 Jun 13;24(23):235503.Catalyst-free vertically aligned graphene nanoflakes possessing a large amount of high density edge planes were functionalized using nitrogen species in a low energy N(+) ion bombardment process to achieve pyridinic, cyanide and nitrogen substitution in hexagonal graphitic coordinated units. The evolution of the electronic structure of the functionalized graphene nanoflakes over the temperature range 20-800 °C was investigated in situ, using high resolution x-ray photoemission spectroscopy. We demonstrate that low energy irradiation is a useful tool for achieving nitrogen doping levels up to 9.6 at.%. Pyridinic configurations are found to be predominant at room temperature, while at 800 °C graphitic nitrogen configurations become the dominant ones. The findings have helped to provide an understanding of the thermal stability of nitrogen functionalities in graphene, and offer prospects for controllable tuning of nitrogen doping in device applications.
- Bookeditors, Sathish Kumar Dundamadappa, Prachi Dubey, Daniel Thomas Ginat, Gul Moonis.Summary: "Prepare for success on the neuroimaging component of the radiology Core Exam! Neuroradiology: A Core Review, 2nd Edition, by Dr. Sathish Kumar Dundamadappa, Prachi Dubey, Daniel Thomas Ginat, and Gul Moonis, is an up-to-date, practical review tool written specifically for the Core Exam. This helpful resource contains 500 image-rich, multiple-choice questions with detailed explanations and annoatated images of right and wrong answers, fully revised content, high-yield tables for easy review, and additional eBook questions to ensure you're ready for the Cor Exam or recertification exam."-- From back cover.Digital Access Ovid [2024]