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Multi-Nozzle Biopolymer Deposition for Freeform Fabrication of Tissue Constructs
Advanced freeform fabrication techniques have been recently used for the construction of tissue
scaffolds because of the process repeatability and capability of high accuracy in fabrication
resolution at the macro and micro scales. Among many applicable tissue scaffolding materials,
polymeric materials have unique properties in terms of the biocompatibility and degradation, and
have thus been widely utilized in tissue engineering applications. Hydrogels, such as alginate,
has been one of the most important polymer scaffolding materials because of its biocompatibility
and internal structure similarity to that of the extracellular matrix of many tissues, and its
relatively moderate processing. Three-dimensional deposition has been an entreating freeform
fabrication method of biopolymer and particularly hydrogel scaffolds because of its readiness to
deposit fluids at ambient temperatures. This paper presents a recent development of biopolymer
deposition based freeform fabrication for 3-diemnsinal tissue scaffolds. The system
configuration of multi-nozzles used in the deposition of sodium alginate solutions and Poly-?-
Caprolactone (PCL) are described. Studies on polymer deposition feasibility and structural
formability are conducted, and the preliminary results are presented.Mechanical Engineerin
Aquaculture for the poor in Cambodia
This lesson learned reviewed the current status of aquaculture in Cambodia. It primarily covers inland fish farming development and coastal aquaculture projects targeted at poverty alleviation and food security. It focuses on approaches aimed at developing low cost systems, and less on high input aquaculture systems that are usually inaccessible to poor families.
Heavy pseudoscalar-meson decay constants with strangeness from the extended nonlocal chiral-quark model
We study the weak-decay constants for the heavy pseudoscalar mesons, D, Ds,
B, and Bs. For this purpose, we employ the extended nonlocal chiral-quark model
(ExNLChQM), motivated by the heavy-quark effective field theory as well as the
instanton-vacuum configuration. In addition to the heavy-quark symmetry and the
nonlocal interactions between quarks and pseudoscalar mesons in ExNLChQM, a
correction for the strange-quark content inside Ds and Bs is also taken into
account and found to be crucial to reproduce the empirical values. From those
numerical results, we obtain f_{D,Ds,B,Bs}=(207.53, 262.56, 208.13, 262.39)
MeV, which are in good agreement with experimental data and other theoretical
estimations. Using those numerical results, we compute the CKM matrix elements
and the Cabibbo angle, using various mesonic and leptonic heavy-meson decay
channels, resulting in
(|V_{cd}|,|V_{cs}|,|V_{ub}|,|V_{td}|/|V_{ts}|)=(0.224,0.968,<5.395*10^{-3},0.215)
and theta_C=12.36^o which are well compatible with available data.Comment: 12 pages, 7 figures, accepted for publication in Mod. Phys. Lett.
Inverted polymer fullerene solar cells exceeding 10% efficiency with poly(2-ethyl-2-oxazoline) nanodots on electron-collecting buffer layers
Polymer solar cells have been spotlighted due to their potential for low-cost manufacturing but their efficiency is still less than required for commercial application as lightweight/flexible modules. Forming a dipole layer at the electron-collecting interface has been suggested as one of the more attractive approaches for efficiency enhancement. However, only a few dipole layer material types have been reported so far, including only one non-ionic (charge neutral) polymer. Here we show that a further neutral polymer, namely poly(2-ethyl-2-oxazoline) (PEOz) can be successfully used as a dipole layer. Inclusion of a PEOz layer, in particular with a nanodot morphology, increases the effective work function at the electron-collecting interface within inverted solar cells and thermal annealing of PEOz layer leads to a state-of-the-art 10.74% efficiency for single-stack bulk heterojunction blend structures comprising poly[4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5-b′]dithiophene-alt-3-fluorothieno[3,4-b]thiophene-2-carboxylate] as donor and [6,6]-phenyl-C71-butyric acid methyl ester as acceptor
Multi-group linear turbo equalization with intercell interference cancellation for MC-CDMA cellular systems.
In this paper, we investigate multi-group linear turbo equalization using single antenna interference cancellation (SAIC) techniques to mitigate the intercell interference for multi-carrier code division multiple access (MC-CDMA) cellular systems. It is important for the mobile station to mitigate the intercell interference as the performance of the users close to cell edge is mainly degraded by the intercell interference. The complexity of the proposed iterative detector and receiver is low as the one-tap minimum mean square error (MMSE) equalizer is employed for mitigating the intracell interference, while a simple group interference canceller is used for suppressing the intercell interference. Simulation results show that the proposed iterative detector and receiver can mitigate the intercell interference effectively through iterations for both uncoded and coded signals
Intermittency in two-dimensional Ekman-Navier-Stokes turbulence
We study the statistics of the vorticity field in two-dimensional
Navier-Stokes turbulence with a linear Ekman friction. We show that the
small-scale vorticity fluctuations are intermittent, as conjectured by Nam et
al. [Phys. Rev. Lett. vol.84 (2000) 5134]. The small-scale statistics of
vorticity fluctuations coincides with the one of a passive scalar with finite
lifetime transported by the velocity field itself.Comment: 4 pages, 7 figure
The role of the resonance in the reaction
We investigate the photo-production in the reaction within the effective Lagrangian method near
threshold. In addition to the "background" contributions from the contact,
channel exchange, and channel nucleon pole terms, which were
already considered in previous works, the contribution from the nucleon
resonance (spin-parity ) is also considered. We show
that the inclusion of the nucleon resonance leads to a fairly good
description of the new LEPS differential cross section data, and that these
measurements can be used to determine some of the properties of this latter
resonance. However, serious discrepancies appear when the predictions of the
model are compared to the photon-beam asymmetry also measured by the LEPS
Collaboration.Comment: 9 pages,6 figures, 1 tabl
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