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A novel hybrid biodegradable Nuss bar model was developed to surgically correct the pectus excavatum and reduce the associated pain during treatment. The scheme consisted of a three-dimensional (3D) printed biodegradable polylactide (PLA) Nuss bar as the surgical implant and electrospun polylactide–polyglycolide (PLGA) nanofibers loaded with lidocaine and ketorolac as the analgesic agents. The degradation rate and mechanical properties of the PLA Nuss bars were characterized after submersion in a buffered mixture for different time periods. In addition, the in vivo biocompatibility of the integrated PLA Nuss bars/analgesic-loaded PLGA nanofibers was assessed using a rabbit chest wall model. The outcomes of this work suggest that integration of PLA Nuss bar and PLGA/analgesic nanofibers could successfully enhance the results of pectus excavatum treatment in the animal model. The histological analysis also demonstrated good biocompatibility of the PLA Nuss bars with animal tissues. Eventually, the 3D printed biodegradable Nuss bars may have a potential role in pectus excavatum treatment in humans.

We study the propagation of a massless scalar wave in de Sitter spacetime perturbed by an arbitrary central mass. By focusing on the late time limit, this probes the portion of the scalar signal traveling inside the null cone. Unlike in asymptotically flat spacetimes, the scalar field amplitude does not decay back to zero but develops a spacetime constant shift, both at zeroth and first order in the central mass. This indicates that massless scalar field propagation in asymptotically de Sitter spacetimes exhibits both linear and nonlinear tail-induced memories

Stent implantation impairs local endothelial function and may be associated with subsequent adverse cardiovascular events. Telmisartan, an angiotensin II receptor blocker that has unique peroxisome proliferator-activated-receptor-gamma-mediated effects on cardiovascular disease, has been shown to enhance endothelial function and limit neointimal hyperplasia. This study utilized hybrid biodegradable/stent nanofibers to facilitate sustained and local delivery of telmisartan to injured arterial vessels. Telmisartan and poly(d,l)-lactide-co-glycolide (PLGA) (75:25) were dissolved in hexafluoroisopropyl alcohol and electrospun into biodegradable nanofibrous tubes which were coated onto metal stents. By releasing 20% of the loaded telmisartan in 30 days, these hybrid biodegradable/stent telmisartan-loaded nanofibers increased the migration of endothelial progenitor cells in vitro, promoted endothelialization, and reduced intimal hyperplasia. As such, this work provides insights into the use of PLGA nanofibers for treating patients with an increased risk of stent restenosis.

We provide evidence that gravitational radiation in a 4D radiation-dominated universe, with equation-of-state $w=1/3$, consists of two components: helicity-2 gravitons and massless scalar acoustic waves. On physical grounds, we would expect the homogeneous solution of the Weyl tensor components to be a good approximation to its inhomogeneous counterparts, whenever the observer is located well in the far zone of an isolated astrophysical source of cosmological gravitational radiation. We show explicitly that these homogeneous and inhomogeneous solutions both receive contributions from the gauge-invariant tensor {\it and} the two Bardeen (acoustic) scalars. Comparison of these Weyl tensor computations thus allows us to not only identify, in the high frequency limit, the corresponding gravitational tensor and scalar radiation; but also their oscillatory polarization patterns., 30 pages, version accepted by PRD

Yi-Pin Chen,1,2 Yen-Wei Liu,3 Demei Lee,3 Jiantai Timothy Qiu,4,5 Tzung-Yan Lee,6,7 Shih-Jung Liu3,8 1Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan; 2Department of Obstetrics and Gynecology, Keelung Chang Gung Memorial Hospital, Keelung, Taiwan; 3Department of Mechanical Engineering, Chang Gung University, Tao-Yuan, Taiwan; 4Department of Obstetrics and Gynecology, Linkou Chang Gung Memorial Hospital, Tao-Yuan, Taiwan; 5Department of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan; 6Graduate Institute of Traditional Chinese Medicine, School of Chinese Medicine, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan; 7Department of Traditional Chinese Medicine, Keelung Chang Gung Memorial Hospital, Keelung, Taiwan; 8Department of Orthopedic Surgery, Linkou Chang Gung Memorial Hospital, Tao-Yuan, Taiwan Background: In this study, we developed biodegradable andrographolide (AG)-eluting nanofibrous mats and evaluated their efficacy in treating cervical cancer. Materials and methods: Membranes of two different poly[(D,L)-lactide-co-glycolide] (PLGA)-to-AG ratios (6:1 and 3:1) were prepared via electrospinning technology. The liberation behavior of AG was evaluated. A cervical cancer model with C57BL/6J mice was created and employed for an invivo efficacy assessment of the drug-eluting nanofibers. Twelve mice with cervical cancer were stochastically divided into three different groups (four animals per group): group A received no treatment as the control, group B was treated with pure PLGA mats, and group C was treated with AG-loaded nanofibrous membranes. The changes in tumor sizes were recorded. Results: All membranes eluted high concentrations of AG at the target area for three weeks, while the systemic drug concentration in the blood remained low. Histological analysis showed no obvious tissue inflammation. Compared with the mice in groups A and B, the tumor size of the mice in group C decreased with time until day 25, when the daily drug concentration reduced to 3 µg/mL. Conclusion: Biodegradable nanofibers with a sustainable release of AG exhibit adequate efficacy and durability for the treatment of mice with cervical cancer. Keywords: andrographolide, cervical cancer, biodegradable nanofiber, sustainable release

The 2.7 inch flexible AMOELD is successfully demonstrated through FTIR analysis and mechanical simulation. Through FTIR analysis we can optimize the CVD parameter to realize the SiNx of WVTR~10−5 (60°/90% R.H.). According to the simulation result, the curvature radius can be reduced to 10mm by modulating the Organic Coating for Planarization(OCP) layer thickness.

Brain abscesses are emergent and life-threating despite advances in modern neurosurgical techniques and antibiotics. The present study explores the efficacy of vancomycin embedded to 50:50 poly(lactic-co-glycolide acid) (PLGA) microparticles in the treatment of brain abscess. The vancomycin embedded microparticles (VMPs) were stereotactically introduced into the cerebral parenchyma in Staphylococcus aureus bacteria- induced brain abscess-bearing rats. Experimental rats were divided into three groups: group A (n = 13, no treatment), group B (n = 14, daily vancomycin injection (5 mg intraperitoneally), and group C (n = 12, stereotactic introduction of VMPs into the abscess cavity). Group C exhibited no inflammatory response and significantly increased survival and reduced mean abscess volumes (p &lt, 0.001) at the eighth week, compared with other groups. Vancomycin delivery via a biodegradable PLGA vehicle can easily attain Area Under the Curve (AUC)/minimum inhibitory concentration (MIC) ratios of &ge, 400, and strengthens the therapeutic efficacy of antibiotics without provoking any potential toxicity. Biodegradable VMPs are a safe and sustainable drug delivery vehicle for the treatment of brain abscess.

Perilla frutescens (L.) Britt Labiatae (Pl), known as “Zi-So” and widely grown in China (red cultivar, Rpl) and Japan (green cultivar, Gpl), is frequently served on “Sa-Shi-Mi” dishes. Considering ...

A robust methodology is established to predict the critical bending radius of a flexible AMOLED. According to the methodology, the critical bending radius of display manufactured by the same process could be reduced from 7 mm to 4 mm by modulating the layer stack thickness.

Ching-Wei Kao,1,2 Yuan-Yun Tseng,3,4 Kuo-Sheng Liu,5 Yen-Wei Liu,5 Jin-Chung Chen,6 Hong-Lin He,7 Yi-Chuan Kau,8 Shih-Jung Liu2,91Department of Anesthesiology, Chiayi Chang Gung Memorial Hospital, Chiayi, Taiwan; 2Department of Mechanical Engineering, Chang Gung University, Taoyuan, Taiwan; 3Division of Neurosurgery, Department of Surgery, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan; 4Department of Surgery, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; 5Department of Thoracic and Cardiovascular Surgery, Linkou Chang Gung Memorial Hospital, Taoyuan, Taiwan; 6Graduate Institute of Biomedical Science, Chang Gung University, Taoyuan, Taiwan; 7Department of Pathology, E-DA Hospital, I-Shou University, Kaohsiung, Taiwan; 8Department of Anesthesiology, Linkou Chang Gung Memorial Hospital, Taoyuan, Taiwan; 9Department of Orthopedic Surgery, Linkou Chang Gung Memorial Hospital, Taoyuan, TaiwanBackground: This study exploited sheath-core-structured lidocaine/human EGF (hEGF)-loaded anti-adhesive poly[(d,l)-lactide-co-glycolide] (PLGA) nanofibrous films for surgical wounds via a co-axial electrospinning technique.Materials and methods: After spinning, the properties of the co-axially spun membranes were characterized by scanning electron microscopy, laser-scanning confocal microscopy, Fourier Transform Infrared spectrometry, water contact angle measurements, and tensile tests. Furthermore, a HPLC analysis and an ELISA evaluated the in vitro and in vivo release curves of lidocaine and hEGF from the films.Results: PLGA anti-adhesion nanofibers eluted high levels of lidocaine and hEGF for over 32 and 27 days, respectively, in vitro. The in vivo evaluation of post-surgery recovery in a rat model demonstrated that no adhesion was noticed in tissues at 2 weeks after surgery illustrating the anti-adhesive performance of the sheath-core-structured nanofibers. Nanofibrous films effectively released lidocaine and hEGF for >2 weeks in vivo. In addition, rats implanted with the lidocaine/hEGF nanofibrous membranes exhibited greater activities than the control demonstrating the pain relief efficacy of the films.Conclusion: The empirical outcomes suggested that the anti-adhesive nanofibrous films with extended release of lidocaine and hEGF offer post-operative pain relief and wound healing.Keywords: sheath-core nanofiber, anti-adhesive membrane, sustained elution, lidocaine, hEGF

Electrospinning has received increasing interest and attention in recent years for fabricating micro/nanofibers of various materials; this is due to its versatility and capability of multiple field applications, including filtration, biosensors, tissue engineering, wound dressings, drug delivery, and composites. Nonetheless, the optimization of the electrospinning process is based on a time-consuming trial-and-error procedure. An empirical study, in conformity with the Taguchi orthogonal matrix design, was carried out to investigate the influence of various processing variables on the electrospinning of resorbable poly(D,L)-lactide-co-glycolide (PLGA). Three different solvents, hexafluoro-2-propanol (HFIP), dichloromethane (DCM), and trichloromethane (TCM), were employed. Five variables were selected for evaluation, including PLGA concentration, the solution’s flow rate from the nozzle, the distance between the nozzle and ground collection, the voltage, and the type of solvents. After electrospinning, we performed a morphological analysis of nanofibers by scanning electron microscopy (SEM) and measured the fiber size by the evaluation of SEM images. Among the variables selected, the type of solvent and the applied voltage were found to be the principal variables influencing the diameter distribution of electrospun PLGA fibers. Nanofibers with the smallest fiber size (466.25±158.38 nm) could be obtained with HFIP solvent and an applied voltage of 15 kV.

We show, through an explicit calculation of the relevant Green's functions, that the transverse-traceless (TT) portion of the gravitational perturbations of Minkowski spacetime and of spatially flat cosmologies with a constant equation-of-state $w$ receive contributions from their isolated matter source(s) outside the past null cone of the observer. This implies the TT gravitational wave (GW) cannot be a standalone observable -- despite widespread (apparent) claims in the gravitational wave literature to the contrary. About a Minkowski background, all 4 of the gauge-invariant variables -- the two scalars, one vector and tensor -- play crucial roles to ensure the spatial tidal forces encoded within the gauge-invariant linearized Riemann tensor are causal. These gravitational tidal forces do not depend solely on the TT graviton but rather on the causal portion of its acceleration. However, in the far zone radiative limit, the flat spacetime `TT' graviton Green's function does reduce to the causal `tt' ones, which are the ones commonly used to compute gravitational waveforms. Similar remarks apply to the spin-1 photon; for instance, the electric field does not depend solely on the photon, but is the causal part of its velocity. As is known within the quantum theory of photons and linearized gravitons, there are obstacles to the construction of simultaneously gauge-invariant and Lorentz-covariant descriptions of these massless spin-1 and spin-2 states. Our results transparently demonstrate that the quantum operators associated with the helicity-1 photon and helicity-2 linear graviton both violate micro-causality: namely, they do not commute outside the light cone in flat and cosmological spacetimes., v3: 64 pages, 1 figure, 4D Minkowski results summarized in Sec. VI, version accepted by CQG. v4: Minor corrections made

Carrier transport in the hexagonal columnar mesophase of a discogen with a built-in dipole moment in the core—hexaalkoxydibenzo[a,c]phenazine (HDBP-3) was investigated. The temperature and field dependences of bipolar carrier mobilities up to the order of 10−3 cm2V−1s−1 in the homeotropically aligned HDBP-3 have been revealed by time-of-flight (TOF) measurement. One-dimensional hopping model was used to discuss the effect of built-in donor–acceptor molecular dipole in the core. The calculation of charge transfer integral also supported the results of mobility measurement. The donor–acceptor molecular dipole in the discogen not only stabilized the mesophase but also contributed to the nondispersive ambipolar nature and substantially enhanced the electron transport in HDBP-3.

Co-axial electrospraying is a simple and versatile process, achieving liquid atomization through electrical forces, to produce core–shell-structured nano/microparticles. Despite its advantages in terms of preparing particles with sizes ranging from 300–500 µm down to 50–70 nm, the optimization of the co-axial electrospraying process remains a challenge. In this study, we investigated experimentally the effects of processing parameters on the size distribution of co-axially electroprayed poly(d,l-lactide-co-glycolide) (PLGA) microparticles. The effects of various parameters, including voltage, flow rate ratio, travel distance, and polymeric concentration, were examined using a factorial experimental design. It was found that the particle size of electrosprayed core–shell microparticles decreases with the voltage and travel distance, and it increases with the flow rate of the solutions and the PLGA concentration in the solutions. Furthermore, to verify the existence of proteins in the co-axially electrosprayed microparticles, PLGA was used as the shell, and recombinant enhanced green fluorescent protein (reGFP) was employed as the core material. Transmission electron microscopy (TEM) and laser scanning confocal microscopy (LSCM) were employed to confirm the core–shell structure of the microparticles. The experimental results demonstrated that under optimum conditions, core–shell-structured microparticles can be successfully prepared using a protein with high activity at the core.

The brane-world scenario provides an intriguing possibility to explore the phenomenological cosmology implied by string/M theory. In this paper, we consider a modified Randall-Sundrum single brane model with two natural generalizations: a Gauss-Bonnet term in the five-dimensional bulk action as well as an induced gravity term in the four-dimensional brane action, which are the leading-order corrections to the Randall-Sundrum model. We study the influence of these combined effects on the evolution of the primordial gravitational waves generated during an extreme slow-roll inflation on the brane. The background, for the early inflationary era, is then modeled through a de Sitter brane embedded within an anti-de Sitter bulk. In this framework, we show that both effects tend to suppress the Randall-Sundrum enhancement of the amplitude of the tensor perturbations at relatively high energies. Moreover, the Gauss-Bonnet effect, relative to standard general relativity, will abruptly enhance the tensor-to-scalar ratio and break the standard consistency relation at high energies, which cannot be evaded by invoking the induced gravity effect, even though the induced gravity strength would mildly counterbalance these significant changes at high energies. We note that the brane-world model with or without the induced gravity effect fulfills the consistency relation. Finally, we discuss some implications of the observational constraints., 13 pages, 5 figures. Version accepted in PRD

We consider a generalization of the Randall-Sundrum single brane-world scenario (RS2). More precisely, the generalization is described through curvature corrections, corresponding to a Gauss-Bonnet term in the bulk and a Hilbert-Einstein term, as well as the strength of the induced gravity term, on the brane. We are mainly interested in analyzing the early inflationary era of the brane, which we model within the extreme slow-roll limit, i.e., under a de Sitter-like brane inflation, where the inflaton field is confined on the brane. We compute the scalar perturbations in this model and compare our results with those previously obtained for the RS2 scenario with and without an induced gravity term on the brane or a Gauss-Bonnet term in the bulk. The amplitude of the scalar perturbations is decreased as compared with a pure RS2 model. In addition, the effect from the Gauss-Bonnet correction in an induced gravity brane-world model is to decrease the amplitude of the scalar perturbations, and a similar result is obtained for the induced gravity effect in a Gauss-Bonnet brane world. In general, in the high energy limit the amplitude is highly suppressed by the Gauss-Bonnet effect. Finally, we constrain the model using the latest WMAP7 data. © 2012 American Physical Society., supported by the Spanish Agency ‘‘Consejo Superior de Investigaciones Científicas’’ through JAEDOC064 and support of the Portuguese Agency ‘‘Fundaçâo para a Ciência e Tecnologia’’ through PTDC/FIS/111032/2009. Support by the Taiwan National Science Council under Project No. NSC 97-2112-M-002- 026-MY3 and by Taiwan’s National Center for Theoretical Sciences (NCTS). P. C. is in addition supported by U.S. Department of Energy under Contract No. DE-AC03- 76SF00515. This work has been supported by a SpanishTaiwanese Interchange Program with reference 2011TW0010 (Spain) and NSC 101-2923-M-002-006- MY3 (Taiwan).

We present a model that attempts to fuse the inflationary era and the subsequent radiation dominated era under a unified framework so as to provide a smooth transition between the two. The model is based on a modification of the generalized Chaplygin gas. We constrain the model observationally by mapping the primordial power spectrum of the scalar perturbations to the latest data of WMAP7. We compute as well the spectrum of the primordial gravitational waves as would be measured today., Comment: 4 pages, 6 figures. Contribution to the Spanish Relativity Meeting (ERE2011), Madrid, Spain

We propose a phenomenological model for the early universe where there is a smooth transition between an early "quintessence" phase and a radiation dominated era. The matter content is modelled by an appropriately modified Chaplygin gas for the early universe. We constrain the model observationally by mapping the primordial power spectrum of the scalar perturbations to the latest data of WMAP7. We compute as well the spectrum of the primordial gravitational waves as would be measured today. We show that the high frequencies region of the spectrum depends on the free parameter of the model and most importantly this region of the spectrum can be within the reach of future gravitational waves detectors., 10 pages, 8 figures. RevTex4

The photophysical properties of a novel small molecule host containing carbazole/dibenzothiophene (CzDBS) were studied. Solution processing of CzDBS found well-balanced bipolar functionalities, high triplet bandgap, and good thin-film morphology. By using this compound as a host material, high-performance solution-processed blue and white phosphorescent organic light emitting devices were fabricated. The blue and white emitting devices showed maximum efficiencies, with 13.9% external quantum efficiency (EQE), 29.7 cd A−1 CE, 18.6 lm W−1 PE and 13.8% EQE, 29.1 cd A−1 CE, and 17.7 lm W−1 PE, respectively. In addition, through incorporation of the light-extraction structures, white-light emission with the Commission Internationale de I'Eclairage chromaticity coordinates (0.38, 0.40) and satisfactory efficiencies of 22.9% EQE, 48.4 cd A−1 CE, and 30.4 lm W−1 PE were demonstrated.

The Dvali-Gabadadze-Porrati brane-world model provides a possible approach to address the late-time cosmic acceleration. However, it has subsequently been pointed out that a ghost instability will arise on the self-accelerating branch. Here, we carefully investigate whether this ghost problem could be possibly cured by introducing the Gauss-Bonnet term in the five-dimensional bulk action, a natural generalization to the Dvali-Gabadadze-Porrati model. Our analysis is carried out for a background where a de Sitter brane is embedded in an anti-de Sitter bulk. Our result shows that the ghost excitations cannot be avoided even in this modified model., 9 pages, 1 figure. Version improved considerably: one footnote removed with extended discussion in Sec. I, a new paragraph added at the end of Sec. IV and another new paragraph in Sec. V, one figure and some references added

MARIAM BOUHMADI-LOPEZ1,2, PISIN CHEN3−6, and YEN-WEI LIU3,5∗ 1Instituto de Estructura de la Materia, IEM-CSIC, Serrano 121, 28006 Madrid, Spain 2Centro Multidisciplinar de Astrofisica CENTRA, Departamento de Fisica, Instituto Superior Tecnico, Av. Rovisco Pais 1,1049-001 Lisboa, Portugal 3Department of Physics, National Taiwan University, Taipei, Taiwan 10617 4Graduate Institute of Astrophysics, National Taiwan University, Taipei, Taiwan 10617 5Leung Center for Cosmology and Particle Astrophysics, National Taiwan University, Taipei, Taiwan 10617 6Kavli Institute for Particle Astrophysics and Cosmology, SLAC National Accelerator Laboratory, Stanford University, Stanford, CA 94305, U.S.A. ∗E-mail: f97222009@ntu.edu.tw