Dynamic depth-dependent osmotic swelling and solute diffusion in articular cartilage monitored using real-time ultrasound

Author name used in this publication: Y. P. ZhengAuthor name used in this publication: J. ShiAuthor name used in this publication: S. G. Patil2003-2004 > Academic research: refereed > Publication in refereed journalAccepted ManuscriptPublishe

New Deformation Twinning Mechanism Generates Zero Macroscopic Strain In Nanocrystalline Metals

Macroscopic strain was hitherto considered a necessary corollary of deformation twinning in coarse-grained metals. Recently, twinning has been found to be a preeminent deformation mechanism in nanocrystalline face-centered-cubic (fcc) metals with medium-to-high stacking fault energies. Here we report a surprising discovery that the vast majority of deformation twins in nanocrystalline Al, Ni, and Cu, contrary to popular belief, yield zero net macroscopic strain. We propose a new twinning mechanism, random activation of partials, to explain this unusual phenomenon. The random activation of partials mechanism appears to be the most plausible mechanism and may be unique to nanocrystalline fcc metals with implications for their deformation behavior and mechanical properties

Enhancing the Prediction of Lung Cancer Survival Rates Using 2D Features from 3D Scans

Author's accepted manuscript.Available from 18/06/2021.acceptedVersio

Surface processes and kinetics of CO2 reduction on Pt(100) electrodes of different surface structure in sulfuric acid solutions

The reduction of CO2 on a Pt(100) electrode in CO2 saturated 0.5 M H2SO4 solutions was studied by in situ FTIR reflection spectroscopy and a programmed potential step technique. Different surface structures of Pt(100) electrode were prepared by different treatments including fast potential cycling (200 V s(-1)) for a known time. The Pt(100) surface was characterized by a parameter gamma that designates the relative amplitude of the current peak of hydrogen adsorption on (100) sites distributed on the one-dimensional surface domains to that on the two-dimensional surface domains. The in situ FTIR spectroscopic results demonstrated that the reduction of CO2 on the Pt(100) dominated by two-dimensional surface domains produced only bridge-bonded CO (COB) species, which give rise to IR absorption near 1840 cm(-1). However both bridge- and linear-bonded CO (COL, yielding IR absorption at around 2010 cm(-1)) species are found for CO2 reduction on the Pt(100) dominated by one-dimensional surface domains. The small intensity of the COL and COB bands indicates that coverage by reduced CO2 species (r-CO2. or COL and COB species) is low. The cyclic voltammetric (CV) studies confirmed quantitatively the in situ FTIRS results, and revealed that the r-CO2 species adsorb preferentially on (100) sites distributed on the two-dimensional surface domains. The initial rate of CO2 reduction upsilon (i), i.e., the rate of CO2 reduction on a clean Pt(100) surface, has been determined quantitatively from studies using a programmed potential step technique. It has been demonstrated that the maximum values of upsilon (i)(upsilon (m)(i)) measured on Pt(100) electrodes with different surface structures all appeared at -0.19 V. From analysis of the relationship between upsilon (m)(i) and gamma we have determined that the upsilon (m)(i) of CO2 reduction on (100) sites distributed on the two-dimensional surface domains is 0.53 x 10(-11) mol cm(-2) s(-1) and that on (100) sites distributed on the one-dimensional surface domains is approximately 2.66 x 10(-11) Mol cm(-2) s(-1). Based on in situ FTIRS and electrochemical studies a migration process of the r-CO2 from the one-dimensional surface domains to the two-dimensional surface domains has been proposed to be involved in CO2 reduction. The present study has thrown new light on the electrocatalytic activity of different surface structures of a Pt(100) electrode and the surface processes and kinetics of CO2 reduction

Fractional crystallization of monosulfide solid solution from sulfide liquids lead to the PGE enrichment in the Jinchuan Ni-Cu sulfide deposit, western China

Discordant lenses of Pt-Pd enriched zones (ores bearing up to 1.0 ppm of Pt or Pd) have recently been identified in the sulfide-bearing peridotite of the Jinchuan Cu-Ni-PGE (Platinum group element) sulfide deposit, China. Chalcopyrite, pyrrhotite, and pentlandite occur in both Pt-Pd enriched zones and normal ores, but Cu-bearing minerals such as cubanite and Bi-, Te-, and As-bearing minerals are more abundant in the Pt-Pd enriched zones. Sperrylite is the major Pt-host minerals in the Pt-Pd enriched zones interstinally and occurs mainly as euhedral grains within base-metal sulfides which occur among the cumulates of olivine. PGE-enrichment is found only in sulfide-bearing samples. In orebody # 1 and orebody 24, Rh, Ru, and Ir are positively correlated, but a negative Ir-Pd and Ir-Pt correlation. However in orebody 2 Rh, Ru, Pt, Pd and Ir are positively correlated. Taken together, the elemental correlations and mineralogical data support a model for the origin of Pt-Pd rich ores in Orebody 1 and Orebody 24 of the Jinchuan deposit are consistent with fractional crystallization of monosulfide solid solution from sulfide liquids on cooling; The origin of Orebody 2 involves variable magma/sulfide liquid mass ratios (R-factors).published_or_final_versio

Novel Block Diagonalization for Reducing Features and Computations in Medical Diagnosis

Author's accepted manuscript.Available from 28/11/2021.acceptedVersio

Characterization of Protective Human CD4+CD25+ FOXP3+ Regulatory T Cells Generated with IL-2, TGF-β and Retinoic Acid

BACKGROUND: Protective CD4+CD25+ regulatory T cells bearing the Forkhead Foxp3 transcription factor can now be divided into three subsets: Endogenous thymus-derived cells, those induced in the periphery, and another subset induced ex-vivo with pharmacological amounts of IL-2 and TGF-β. Unfortunately, endogenous CD4+CD25+ regulatory T cells are unstable and can be converted to effector cells by pro-inflammatory cytokines. Although protective Foxp3+CD4+CD25+ cells resistant to proinflammatory cytokines have been generated in mice, in humans this result has been elusive. Our objective, therefore, was to induce human naïve CD4+ cells to become stable, functional CD25+ Foxp3+ regulatory cells that were also resistant to the inhibitory effects of proinflammatory cytokines. METHODOLOGY/PRINCIPAL FINDINGS: The addition of the vitamin A metabolite, all-trans retinoic acid (atRA) to human naïve CD4+ cells suboptimally activated with IL-2 and TGF-β enhanced and stabilized FOXP3 expression, and accelerated their maturation to protective regulatory T cells. AtRA, by itself, accelerated conversion of naïve to mature cells but did not induce FOXP3 or suppressive activity. The combination of atRA and TGF-β enabled CD4+CD45RA+ cells to express a phenotype and trafficking receptors similar to natural Tregs. AtRA/TGF-β-induced CD4+ regs were anergic and low producers of IL-2. They had potent in vitro suppressive activity and protected immunodeficient mice from a human-anti-mouse GVHD as well as expanded endogenous Tregs. However, treatment of endogenous Tregs with IL-1β and IL-6 decreased FOXP3 expression and diminished their protective effects in vivo while atRA-induced iTregs were resistant to these inhibitory effects. CONCLUSIONS/SIGNIFICANCE: We have developed a methodology that induces human CD4(+) cells to rapidly become stable, fully functional suppressor cells that are also resistant to proinflammatory cytokines. This methodology offers a practical novel strategy to treat human autoimmune diseases and prevent allograft rejection without the use of agents that kill cells or interfere with signaling pathways

A Robust Peak-to-Average Power Ratio Reduction Scheme by Inserting Dummy Signals with Enhanced Partial Transmit Sequence in OFDM Systems.

Peak-to-average power ratio (PAPR) is one of the main drawbacks in orthogonal frequency division multiplexing (OFDM) systems. High PAPR forces the power amplifier to back off in order to operate in its linear region, which degrades the power efficiency of the system. Several PAPR reduction techniques have been developed, but most of them have not considered both complexity and PAPR reduction. In this paper, a novel PAPR reduction scheme based on the insertion of dummy sequences to an enhanced partial transmit sequence is proposed. By applying this scheme the PAPR performance is enhanced compared to the conventional methods while the complexity is significantly reduced. Numerical analysis is carried out with OFDM signal and QPSK modulation

Nodal quasiparticle meltdown in ultra-high resolution pump-probe angle-resolved photoemission

High-$T_c$ cuprate superconductors are characterized by a strong momentum-dependent anisotropy between the low energy excitations along the Brillouin zone diagonal (nodal direction) and those along the Brillouin zone face (antinodal direction). Most obvious is the d-wave superconducting gap, with the largest magnitude found in the antinodal direction and no gap in the nodal direction. Additionally, while antinodal quasiparticle excitations appear only below $T_c$, superconductivity is thought to be indifferent to nodal excitations as they are regarded robust and insensitive to $T_c$. Here we reveal an unexpected tie between nodal quasiparticles and superconductivity using high resolution time- and angle-resolved photoemission on optimally doped Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$. We observe a suppression of the nodal quasiparticle spectral weight following pump laser excitation and measure its recovery dynamics. This suppression is dramatically enhanced in the superconducting state. These results reduce the nodal-antinodal dichotomy and challenge the conventional view of nodal excitation neutrality in superconductivity.Comment: 7 pages, 3 figure. To be published in Nature Physic