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Post-processing treatment of conductive polymers to enhance electrical conductivity
A method for enhancing electrical conductivity of a film which includes at least one conductive polymer. The method includes providing the film comprising the at least one conductive polymer and at least one polymer acid, agitating the film in at least one reagent; and, placing the film on a heated surface. The at least one reagent includes a reagent acid that is stronger than the polymer acid. The conductivity of the treated film is significantly greater than the conductivity of the untreated film.Board of Regents, University of Texas Syste
Estimates of Discharge Coefficient in Levee Breach Under Two Different Approach Flow Types
The amount of released water (discharge) in a levee breach is a primary input variable to establish an emergency action plan for the area next to the levee. However, although several studies have been conducted, there is still no widely applicable discharge coefficient formula; this needs to be known to estimate discharge amount through an opening caused by a levee breach. Sometimes, the discharge coefficient developed for a sharp crested side weir is used to rate the discharge, but, in case of a levee breach, the resulting geometry and flow types are similar to that over a broad crested weir. Thus, in this study, two different openings—rectangular and trapezoidal shape—are constructed in the center of a levee at a height of 0.6m to replicate levee breach scenarios, and the effect of two different approach flow types—the river type approach and reservoir type approach—are explored to suggest a discharge coefficient formula applicable for discharge rating for a levee breach. The results show that the ratio of head above the bottom of an opening and the opening width is a key variable for calculating the discharge coefficient of a reservoir type, but the approach Froude number should also be considered for a river type approach. The measured data are used to improve rating equations and will be useful in the future to validate computational fluid dynamics simulations of wave propagation during levee failure into the inundation area
Orbital selective Fermi surface shifts and mechanism of high T superconductivity in correlated AFeAs (A=Li,Na)
Based on the dynamical mean field theory (DMFT) and angle resolved
photoemission spectroscopy (ARPES), we have investigated the mechanism of high
superconductivity in stoichiometric LiFeAs. The calculated spectrum is in
excellent agreement with the observed ARPES measurement. The Fermi surface (FS)
nesting, which is predicted in the conventional density functional theory
method, is suppressed due to the orbital-dependent correlation effect with the
DMFT method. We have shown that such marginal breakdown of the FS nesting is an
essential condition to the spin-fluctuation mediated superconductivity, while
the good FS nesting in NaFeAs induces a spin density wave ground state. Our
results indicate that fully charge self-consistent description of the
correlation effect is crucial in the description of the FS nesting-driven
instabilities.Comment: 5 pages, 4 figures, supporting informatio
Prediction of Individual Propofol Requirements based on Preoperative EEG Signals
The patient must be given an adequate amount of propofol for safe surgery
since overcapacity and low capacity cause accidents. However, the sensitivity
of propofol varies from patient to patient, making it very difficult to
determine the propofol requirements for anesthesia. This paper aims to propose
a neurophysiological predictor of propofol requirements based on the
preoperative electroencephalogram (EEG). We exploited the canonical correlation
analysis that infers the amount of information on the propofol requirements.
The results showed that the preoperative EEG included the factor that could
explain the propofol requirements. Specifically, the frontal and posterior
regions had crucial information on the propofol requirements. Moreover, there
was a significantly different power in the frontal and posterior regions
between baseline and unconsciousness periods, unlike the alpha power in the
central region. These findings showed the potential that preoperative EEG could
predict the propofol requirements.Comment: 5 pages, 1 figure, 1 tabl
Implantation of Decellularized Extracellular Matrix with Resistance Training Effectively Repairs a Volumetric Muscle Loss
PURPOSE Skeletal muscle has remarkable regenerative capacity in most minor injuries induced by mechanical laceration, overstretching, and toxins. However, volumetric muscle loss (VML) injury, a large volume of muscle loss beyond the self-repair capacity, causes functional disability and morphological deformities. This study investigated the effects of myofiber injection into a decellularized extracellular matrix (ECM) and resistance training (RT) on skeletal muscle regeneration following VML injury. METHODS 6-months-old male Fischer CDF rats and 2-months-old F344-Tg (UBC-EGFP) rats (myofiber donors) were used in this study. Approximately 20% of the mass of the lateral gastrocnemius (LGAS) was excised and replaced by ECM of similar dimensions. Thirty myofibers were injected into the injured region seven days post-injury. Ladder climbing (RT) was allowed 10 days post-defect surgery, and the rats were subjected to ladder climbing with a weight every third day for 6 weeks. RESULTS After 56 days of recovery and exercise training, the cross-sectional area (CSA) of intact muscle in the EXE group (5,104±92 μm2) increased significantly compared to that in the ECM (4,657±79 μm2) group. The number of blood vessels larger than 20 μm in diameter, capillaries excluded, showed a significant difference between the ECM+EXE (34.25±4.2) and ECM (21.75±3.89) groups. A significant reduction of fibrosis in the ECM+EXE (44.50±1.6%) group was observed compared to the ECM (69.25±1.9%) and ECM+FIB+EXE (63.00±1.7%) groups. Moreover, the small muscle fiber area within the transplanted ECM was significantly larger in the ECM+EXE (1.37±0.03 mm2) than in both the ECM (0.49±0.01 mm2) and ECM+FIB (0.62±0.01 mm2) groups. CONCLUSIONS These data suggest that ECM transplantation with RT effectively repairs VML by enhancing hypertrophy, angiogenesis, and myofiber infiltration throughout the entire ECM
Therapeutic Sources of Skeletal Muscle Regeneration from Volumetric Muscle Loss: A Narrative Review
PURPOSE Minor skeletal muscle injuries can be repaired, but more extensive volumetric muscle loss (VML) leads to a permanent functional disability with ambiguous therapeutic outcomes, and reconstructive surgical procedures are constrained by donor tissue scarcity. This review assessed the considerable attention paid to biomaterials in healing damaged skeletal muscle. METHODS A comprehensive search in PubMed, Web of Science, Google Scholar, and Wiley Online Library was conducted to obtain previous studies exploring the state of biocompatible tissue scaffolds for VML recovery. RESULTS By regenerating the function of damaged skeletal muscle, tissue-engineered skeletal muscle construction could revolutionize the treatment of VML. However, transporting cells into the wounded muscle location presents a significant challenge because it may result in unfavorable immunological reactions. The development and validation of several biomaterials with varying physical and chemical natures to treat various muscle injuries have recently been undertaken to overcome this problem. This review discusses the relative benefits of satellite cells (SC), the most prevalent skeletal muscle stem cells employed to seed scaffolds. CONCLUSIONS Biomaterials can be used with skeletal muscle stem cells and growth factors to repair VML because of their customizable and desirable physicochemical qualities. Owing to the capacity of SCs for self-renewal and their undifferentiated state, these cells are excellent candidates for cell therapy. A large gap exists between understanding SC behavior and how it can be used to repair and regenerate human skeletal muscle tissue. Thus, this review sought to portray the current knowledge on the lifespan of SCs and their involvement in exercise-induced muscle regeneration and hypertrophy
Radiative Transfer in Ly{\alpha} Nebulae: I. Modeling a Continuous or Clumpy Spherical Halo with a Central Source
To understand the mechanism behind high- Ly nebulae, we simulate
the scattering of Ly in a halo about a central
Ly source. For the first time, we consider both smooth and clumpy
distributions of halo gas, as well as a range of outflow speeds, total column densities, spatial concentrations, and central source
galaxies (e.g., with Ly line widths corresponding to those typical of
AGN or star-forming galaxies). We compute the spatial-frequency diffusion and
the polarization of the Ly photons scattered by atomic hydrogen. Our
scattering-only model reproduces the typical size of Ly nebulae
(kpc) at total column densities and predicts a range of positive, flat, and negative polarization
radial gradients. We also find two general classes of Ly nebula
morphologies: with and without bright cores. Cores are seen when
is low, i.e., when the central source is directly visible, and are associated
with a polarization jump, a steep increase in the polarization radial profile
just outside the halo center. Of all the parameters tested in our smooth or
clumpy medium model, dominates the trends. The radial behaviors of
the Ly surface brightness, spectral line shape, and polarization in
the clumpy model with covering factor approach those of the
smooth model at the same . A clumpy medium with high
and low generates Ly features via scattering that
the smooth model cannot: a bright core, symmetric line profile, and
polarization jump.Comment: 42 pages, 27 figures, accepted for publication in ApJ, Comments
welcome
Insight into highly conserved H1 subtype-specific epitopes in influenza virus hemagglutinin
Influenza viruses continuously undergo antigenic changes with gradual accumulation of mutations in hemagglutinin (HA) that is a major determinant in subtype specificity. The identification of conserved epitopes within specific HA subtypes gives an important clue for developing new vaccines and diagnostics. We produced and characterized nine monoclonal antibodies that showed significant neutralizing activities against H1 subtype influenza viruses, and determined the complex structure of HA derived from a 2009 pandemic virus A/Korea/01/2009 (KR01) and the Fab fragment from H1-specific monoclonal antibody GC0587. The overall structure of the complex was essentially identical to the previously determined KR01 HA-Fab0757 complex structure. Both Fab0587 and Fab0757 recognize readily accessible head regions of HA, revealing broadly shared and conserved antigenic determinants among H1 subtypes. The beta-strands constituted by Ser110-Glu115 and Lys169-Lys170 form H1 epitopes with distinct conformations from those of H1 and H3 HA sites. In particular, Glu112, Glu115, Lys169, and Lys171 that are highly conserved among H1 subtype HAs have close contacts with HCDR3 and LCDR3. The differences between Fab0587 and Fab0757 complexes reside mainly in HCDR3 and LCDR3, providing distinct antigenic determinants specific for 1918 pdm influenza strain. Our results demonstrate a potential key neutralizing epitope important for H1 subtype specificity in influenza virus
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