Small gold nanoparticles presenting linear and looped Cilengitide analogues as radiosensitizers of cells expressing α<Subscript>ν</Subscript>β<Subscript>3</Subscript> integrin

This work uses linear and looped RGDfV sequences attached to the surface of small (1.8 nm in diameter) gold nanoparticles (AuNPs) to enhance the radiosensitizating effects of Cilengitide, a cyclic RGDf (NMe)V pentapeptide that targets α_vβ₃ integrin which is overexpressed in certain cancers. Following synthesis and purification, the AuNPs were evaluated in vitro against HUVEC, H460, and MCF7 cells in clonogenic assays using a ¹³⁷Cs irradiator. Untargeted AuNPs induced no significant dose enhancement factors (DEFs) in any of the cell types when compared to radiation treatment alone, whereas all evaluated AuNPs functionalized with targeting peptides performed at least as well as controls (irradiation after Cilengitide treatment). The observed DEFs also suggest that cyclizing the linear peptides into more spatially constrained, looped structures may facilitate target binding. These greater dose enhancements merit future in vivo studies of drug-AuNP conjugates to assess the ability of the nanostructures to provide an improved therapeutic benefit over treatment with drug candidates and radiation alone.

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Grating-Outcoupled Radiation in Second-Order Fiber Bragg Gratings

Abstract

The experimental results of the radiation for second-order fiber Bragg gratings, which are made of a single-mode photosensitive fiber (PS-1500; Fiber-Core Corp.) and a single-mode fiber (SMF-28; Corning Inc.), by a phase mask writing fabrication technique are explored. For PS-1500 fiber Bragg gratings, the maximum radiation efficiency of ?23.5 dB at resonance λ = 1,539.34 nm with a very narrow bandwidth (about 0.02 nm) are measured from a 10-mm-diameter photo-detector, while for SMF-28 fiber Bragg gratings, the maximum radiation efficiency is ?34.6 dB (λ = 1,538.03 nm) with a bandwidth of 0.06 nm. The total efficiencies of the radiation are about ?16.8 dB for PS-1500 fiber Bragg gratings and ?28.1 dB for SMF-28 fiber Bragg gratings.     

Textured growth of CoFe for soft underlayers in CoCrPt:SiO2 perpendicular magnetic recording media

CoFe alloy thin films were studied with the intention of potential use as a soft underlayer (SUL) for Co-based perpendicular recording media. The effect of composition and the effects of seedlayers on the formation of crystalline phase and crystallographic texture and the magnetic properties were investigated. Films deposited on Ta/Pd seedlayer were found to have a good FCC(1 1 1) texture than those deposited on glass substrates or on Ta seedlayers. The magnetic properties were also better when deposited on Ta/Pd seedlayers. On these seedlayers, Fe concentration of 15 at% was found to be suitable for the formation of FCC phase. Disks were prepared with CoFe SULs. The noise of CoFe SUL is one of the challenges to be solved.     

Characterization of ZnO-Cu2O crystal films by electrochemical codeposition

Journal of Solid State Electrochemistry - Codeposition of mixed ZnO and Cu2O (ZnO-Cu2O) crystal films using electrochemical deposition (ECD) was investigated. The ZnO-Cu2O films were prepared using...     

A NEW FINITE ELEMENT APPROXIMATION OF A STATE-CONSTRAINED OPTIMAL CONTROL PROBLEM

In this paper, we study numerical methods for an optimal control problem with pointwise state constraints. The traditional approaches often need to deal with the deltasingularity in the dual equation, which causes many difficulties in its theoretical analysis and numerical approximation. In our new approach we reformulate the state-constrained optimal control as a constrained minimization problems only involving the state, whose optimality condition is characterized by a fourth order elliptic variational inequality. Then direct numerical algorithms （nonconforming finite element approximation） are proposed for the inequality, and error estimates of the finite element approximation are derived. Numerical experiments illustrate the effectiveness of the new approach.     

Structural and compositional changes in ion-bombarded Ta2O5

A detailed study of the effect of heavy-ion bombardment on Ta₂O₅ has been undertaken using a combination of radioactive tracer techniques, electron microscopy, and Rutherford backscattering. Crystalline Ta₂O₅ is amorphized at ~6 × 10¹³ ions cm^?2, while at a dose of ~5 × 10¹⁶ ions cm^?2 the electron microscopy reveals the development of random grains of a new crystalline phase. By ~1 × 10¹⁷ ions cm^?2 the grains are not yet overlapping but still yield a diffraction pattern consistent with either δ-Ta-O (not to be confused with TaO) or Ta_1?xO₂, thus indicating that Ta₂O₅, like most other transition-metal oxides, is subject to preferential sputtering. Preferential sputtering was confirmed by backscattering analysis of specimens bombarded to high doses, where the average surface composition was found to be Ta_1.8±0.2O₂ or, equivalently, Ta₂O_2.2±0.2. The surface alteration had an average composition independent of the mass and energy of the incident ions.     

13C nmr spectroscopy of tetracarbocyclic diterpenes and related substances1

A caarbon shift analysis of hibaene, phyllocladene, cafestol, cafamarine, mascaroside and hilbane-like substances is presented.     

Preparation of porous biodegradable PLLA with tunable pore size through simple variation of PEG/PLLA-blend crystallization conditions

In this study, porous poly(L-lactic acid) (PLLA) films are prepared via a facile and low-cost approach using poly(ethylene glycol) (PEG) and solution casting. In contrast to most studies, the PEG/PLLA samples are further processed under different crystallization conditions (i.e., different PLLA crystallization temperatures) before PEG removal. As the PEG is extracted via solvent at higher PLLA crystallization temperatures, the resultant PLLA samples have larger pores. Interconnected fibrillar-shaped pores are found in all systems, and the fibrillar-porous structure width is ~150 nm–1.2 μm, as observed via scanning electron microscopy. These pore sizes can be tuned by adjusting the blend composition and crystallization temperature. In addition, PEG/PLLA blends are subjected to hydrolytic degradation analysis according to their crystallization conditions. Higher PLLA crystallization temperature yields higher PLLA crystallinity and larger pores, as well as reduced surface interaction with water. Therefore, the PLLA degradation rate is decreased. The developed PLLA films have potential applications in drug delivery and tissue engineering.     

Using Bidimensional Multiscale Entropy Analysis of Ultrasound Images to Assess the Effect of Various Walking Intensities on Plantar Soft Tissues

Walking performance is usually assessed by linear analysis of walking outcome measures. However, human movements consist of both linear and nonlinear complexity components. The purpose of this study was to use bidimensional multiscale entropy analysis of ultrasound images to evaluate the effects of various walking intensities on plantar soft tissues. Twelve participants were recruited to perform six walking protocols, consisting of three speeds (slow at 1.8 mph, moderate at 3.6 mph, and fast at 5.4 mph) for two durations (10 and 20 min). A B-mode ultrasound was used to assess plantar soft tissues before and after six walking protocols. Bidimensional multiscale entropy (MSE_2D) and the Complexity Index (CI) were used to quantify the changes in irregularity of the ultrasound images of the plantar soft tissues. The results showed that the CI of ultrasound images after 20 min walking increased when compared to before walking (CI₄: 0.39 vs. 0.35; CI₅: 0.48 vs. 0.43, p < 0.05). When comparing 20 and 10 min walking protocols at 3.6 mph, the CI was higher after 20 min walking than after 10 min walking (CI₄: 0.39 vs. 0.36, p < 0.05; and CI₅: 0.48 vs. 0.44, p < 0.05). This is the first study to use bidimensional multiscale entropy analysis of ultrasound images to assess plantar soft tissues after various walking intensities.     

Photosensitized growth of TiO2 nanoparticles improved the charge transfer dynamics of a bichromophoric dye

Nanostructured TiO₂ particles utilized in dye-sensitized solar cells (DSSCs) provide a large surface area, which facilitates the adsorption of sensitizing dye and charge recombination due to the high density of surface traps. In this article, a modified surface of TiO₂ nanoparticles was successfully synthesized in the presence of (1-hydroxycyclohexyl)(phenyl)methanone (HCPM) as a sensitizer to control formation in a toluene/ethanol medium via a photolytic process. A particle-size analysis showed that the oxides which had fully oxidized to TiO₂ were 20～35 nm in diameter. The structure of the TiO₂ particles being of an amorphous nature and the nearly defect-free distributions of Ti⁴⁺ and O^2- energy levels imply that the grain boundaries and surface trap sites were effectively suppressed. TiO₂ particles were subsequently blended with the bichromophoric dye, AMIP, to study fluorescence decay dynamics between AMIP/TiO₂ interfaces. Fluorescence lifetime measurements gave the rate constant for the charge-transfer process from the excited singlet of AMIP to the conduction band of TiO₂ as 1.2×10⁹ s^?l. When PL quenching measured as the TiO₂ contents of these composites reached a 2.5 wt% level, the maximum enhanced charge-transfer dynamics occurred. Structural properties and photophysical behaviors of composites of AMIP bound to TiO₂ were extensively demonstrated.