bluuebunny/crossref_metadata_2025_split huggingface dataset:
The latent structure of the Peritraumatic Dissociative Experiences Questionnaire
Authors: Brooks Robert , Bryant Richard A. , Silove Derrick , Creamer Mark , O'Donnell Meaghan , McFarlane Alexander C. , Marmar Charles R. 
Published: April 2009

AbstractThis paper has been retracted due to a publisher's error: the order of the authors was incorrect. The Editor and Publisher of the Journal of Traumatic Stress apologize to the authors and our readership. The Peritraumatic Dissociative Experiences Questionnaire (PDEQ) is a widely used measure of peritraumatic dissociation, and is presumably a unidimensional construct. Two hundred forty‐seven individuals admitted to five hospitals after traumatic injury were administered the Clinician Administered PTSD Scale, the Hospital Anxiety and Depression Scale, and the PDEQ. Factor analysis indicated that the PDEQ involved two factors containing four items each: one factor (altered awareness) indexes alterations in awareness and the other (derealization) reflects distortions in perceptions of the self and the world. Only the derealization factor was associated with acute stress, anxiety, and depression symptoms. Cross‐validation with independent data provided only partial support for the 2‐factor structure model. These data indicate that peritraumatic dissociation may involve two distinct constructs.
Preparation and Characterization of Novel Quaternized Cellulose Nanoparticles as Protein Carriers
Authors: Song Yongbo , Zhou Jinping , Li Qian , Guo Yi , Zhang Lina 
Published: April 2009

AbstractQuaternized cellulose (QC) nanoparticles were prepared in distilled water by ionic crosslinking of QC with sodium tripolyphosphate (TPP) for the first time. BSA as a model protein drug was used to investigate the loading and release features of the nanoparticles. The results indicated that QC nanoparticles had high loading efficiency and capacity for BSA. The in vitro BSA release of the QC nanoparticles displayed a burst effect in the first 2 h and then a slow continuous release. Nanoparticles with a higher DS of QC showed a decrease in particle size, an increase in zeta potential, a higher loading efficiency and a slower drug‐release profile. These studies demonstrated that QC nanoparticles are potential protein carriers, and that their physicochemical properties and release profile could be easily adjusted.magnified image
Therapeutic Efficacy of 2‐Methoxyestradiol Microcrystals Encapsulated within Polyelectrolyte Multilayers
Authors: Wang Su He , Shi Xiangyang , Chen Xisui , Baker James R. 
Published: April 2009

AbstractDevelopment of a novel formulation of anticancer drugs to improve their water‐solubility and bioavailability remains a great challenge. Herein, the potential anticancer agent 2‐methoxyestradiol (2‐ME) was selected as a model drug and was encapsulated within polyelectrolyte (PE) multilayers by layer‐by‐layer deposition of oppositely charged PEs onto the drug microcrystal surfaces. Cell viability and morphology observation of two cell lines reveal that the PE multilayer‐encapsulated 2‐ME microcrystals markedly decrease the cell viability, displaying similar inhibitory effect to that of the conventional formulation of 2‐ME dissolved in ethanol. The current approach to encapsulate hydrophobic drug microparticles may be useful for formulating different drugs for a variety of biological applications.magnified image
Online HPLC‐NMR of PS‐b‐PMMA and Blends of PS and PMMA, 2 ‐ LCCC‐NMR at Critical Conditions of PMMA
Authors: Hiller Wolf , Sinha Pritish , Pasch Harald 
Published: April 2009

AbstractPS‐b‐PMMA copolymers and blends of PS and PMMA were analyzed by the online coupling of LC at the critical point of adsorption and 1H NMR. The separation of the polymers was carried out at chromatographic conditions which correspond to the critical point of PMMA and the size exclusion mode of PS. It was shown that blends of PS and PMMA homopolymers could be well separated at critical conditions of PMMA. The analysis of both the copolymers and the blends were carried out by online coupled 1H NMR. The block copolymers were analyzed with respect to the chemical composition. LCCC‐NMR coupling was allowed to determine the individual blocks of the copolymers regarding molar mass. The data were compared with the separation at critical conditions of PS.magnified image
Novel Biodegradable Heterografted Polymer Brushes Prepared via a Chemoenzymatic Approach
Authors: Hans Marc , Xiao Yan , Keul Helmut , Heise Andreas , Moeller Martin 
Published: April 2009

AbstractBiodegradable heterografted molecular bottle brushes were prepared in two steps starting with a linear polyglycidol as a macroinitiator. First, ca. 45% of the polyglycidol hydroxy groups were grafted with ε‐caprolactone via enzymatic catalysis. Selective end capping of the hydroxy groups at the graft ends was achieved via enzymatic esterification with vinyl acetate or vinyl acrylate. Finally, poly(L‐lactide) grafts were attached to the remaining polyglycidol hydroxy groups by chemically catalyzed ring‐opening polymerization. The successful synthesis of the heterografted comb‐shaped brushes was confirmed by NMR and SEC analyses. Additionally, the feasibility of microsphere formulation was described.magnified image
Microwave‐Assisted Modification of Poly(vinylimidazolium salts) via N,N‐Dimethylformamide Decomposition
Authors: Dickmeis Marcus , Ritter Helmut 
Published: April 2009

AbstractThe modification of poly(1‐propyl‐3‐vinylimidazolium bromide) (3a), poly(1‐hexyl‐3‐vinylimidazolium bromide) (3b), poly(1‐isopropyl‐3‐vinylimidazolium bromide) (3c), poly(1‐benzyl‐3‐vinylimidazolium bromide) (3d), poly(1‐(1‐phenylethyl)‐3‐vinylimidazolium bromide) (3e) has been conducted under microwave irradiation using N,N‐dimethylformamide as solvent and reagent. The products were formed by the decomposition of N,N‐dimethylformamide into dimethylamine and carbon monoxide. The proposed structure of the obtained copolymer contains mainly units of 1‐vinylimidazole and some units of amines, formamides, and alkenes. The reaction mechanism was established by use of model compounds 1‐propyl‐3‐methylimidazolium bromide (5a), 1‐hexyl‐3‐methylimidazolium bromide (5b), 1‐isopropyl‐3‐methylimidazolium bromide (5c), 1‐benzyl‐3‐methylimidazolium bromide (5d), 1‐(1‐phenylethyl)‐3‐methylimidazolium bromide (5e), 1‐hexadecyl‐3‐methylimidazolium bromide (5f).magnified image
Synthesis and Characterization of Organic/Inorganic Polyrotaxanes from Polyhedral Oligomeric Silsesquioxane and Poly(ethylene oxide)/α‐Cyclodextrin Polypseudorotaxanes via Click Chemistry
Authors: Zeng Ke , Zheng Sixun 
Published: April 2009

AbstractOrganic/inorganic polyrotaxanes were synthesized via Huisgen 1,3‐dipolar cycloaddition between 3‐azidapropylhepta(3,3,3‐trifluoropropyl) POSS and dialkyne‐terminated PEO/α‐cyclodextrin polypseudorotaxanes. The organic/inorganic hybrid polyrotaxanes were characterized by means of 1H NMR spectroscopy and WAXRD. It was found that the nanosized POSS blocking agents significantly affected the crystal structures of polyrotaxanes. Thermal gravimetric analysis showed that the organic/inorganic hybrid polyrotaxanes exhibited enhanced thermal stability compared to their parent polypseudorotaxanes, in terms of rate of thermal degradation and the summation of char and ceramic yields.magnified image
New Cyclic Olefin Copolymer for the Preparation of Thermally Responsive Luminescent Films
Authors: Donati Filippo , Pucci Andrea , Boggioni Laura , Tritto Incoronata , Ruggeri Giacomo 
Published: April 2009

AbstractPolymer films with optical properties as indicators to thermal stress were obtained through the controlled dispersion of moderate amounts (≤0.1 wt.‐%) of the 4,4′‐bis(2‐benzoxazolyl)stilbene (BBS) dye into a new semicrystalline ethylene‐norbornene (E‐co‐N, N content of 15.3 mol.‐%) copolymer characterized by a glass transition temperature (Tg) of about 64 °C. All the pristine films showed optical characteristics coming from noninteracting BBS chromophores. In contrast permanent optical changes were detected after film annealing at a T ≥ Tg due to the variation of the BBS supramolecular structure. The easy modulation of the optical features of polymer films by thermal perturbations suggests applications as threshold temperature visual indicators in thermoplastic materials.magnified image
Synthesis of Chitosan Surfactants
Authors: Fricke Nicole , Keul Helmut , Möller Martin 
Published: April 2009

AbstractChitosan surfactants were prepared in a three‐step reaction starting with glycol chitosan (GC) and chitosan oligosaccharides (COS). In the case of GC, water‐insoluble products were obtained, the functionalisation of which were proven via IR spectroscopy. Starting with COS, a broad variety of products with different ratios of ionic and hydrophobic side chains were prepared and characterised by NMR and partially by IR spectroscopy. Thermogravimetric analysis showed that the thermal stability of functionalised COS did not change. The critical micelle concentration (cmc) was determined from surface tension measurements to be 0.01 mg · mL−1 for a sample of ionic to hydrophobic units of 1:1.magnified image
Alkylthio‐Substituted Polythiophene: Absorption and Photovoltaic Properties
Authors: Huo Lijun , Zhou Yi , Li Yongfang 
Published: April 2009

AbstractTwo polythiophene derivatives with electron‐donating alkylthio side chains, poly[(3‐hexylthio)thiophene] (P3HST) and poly[(3‐hexylthio)thiophene‐alt‐thiophene] (P3HST‐co‐Th) have been synthesized and characterized. Both P3HST and P3HST‐co‐Th show broader absorption peaks than poly(3‐hexylthiophene). Meanwhile, the alkylthio side chains decrease the HOMO energy level of the polymers, which benefits the higher open circuit voltage of the polymer solar cells (PSCs) based on the polymer as donor. PSCs have been fabricated with the polymers as donor and [6,6]‐phenyl C61 butyric acid methyl ester as acceptor (1: 1, w/w). The devices based on P3HST and P3HST‐co‐Th show an open circuit voltage of 0.63 V, and a power conversion efficiency of 0.34% and 0.5%, respectively, under the illumination of AM1.5, 80 mW · cm−2.magnified image
Water Soluble Star‐block Copolypeptides: Towards Biodegradable Nanocarriers for Versatile and Simultaneous Encapsulation
Authors: Zhuang Wensheng , Liao Lihui , Chen Heru , Wang Jinzhi , Pan Ying , Zhang Lumian , Liu Daojun 
Published: April 2009

AbstractThe synthesis of water soluble star‐block copolypeptides and their encapsulation properties are described. The star‐block copolypeptides, obtained by ring‐opening polymerization of amino acid N‐carboxyanhydrides, consist of a PEI core, a hydrophobic polyphenylalanine or polyleucine inner shell, and a negatively charged polyglutamate outer shell. The encapsulation study showed that these water soluble, amphiphilic star‐block copolypeptides could simultaneously encapsulate versatile compounds ranging from hydrophobic to anionic and cationic hydrophilic guest molecules.magnified image
Similarities in the Structural Organization of Major and Minor Ampullate Spider Silk
Authors: Papadopoulos Periklis , Ene Roxana , Weidner Immanuel , Kremer Friedrich 
Published: April 2009

AbstractMinor and major ampullate spider silks are studied under varying mechanical stress by static and time‐resolved FT‐IR spectroscopy. This enables one to trace the external mechanical excitation on a microscopic level and to determine for the different moieties the time dependence of the molecular order parameters and corresponding band shifts. It is concluded that the hierarchical nanostructure of both types of silk is similar, being composed of highly oriented nanocrystals, which are interconnected by amorphous chains that obey the worm‐like chain model and have a Gaussian distribution of pre‐strain. By that it is possible to describe the mechanical properties of both silks by two adjustable parameters only, the center and width of the distribution. For major ampullate silk, the observed variability is small in pronounced contrast to the findings for minor ampullate.magnified image
Mesoscopic Membrane Physics: Concepts, Simulations, and Selected Applications
Authors: Deserno Markus 
Published: April 2009

AbstractThe window of a few tens to a few hundred nanometers in length scale is a booming field in lipid membrane research, owing largely to two reasons. First, many exciting biophysical and cell biological processes take place within it. Second, experimental techniques manage to zoom in on this sub‐optical scale, while computer simulations zoom out to system sizes previously unattainable, and both will be meeting soon. This paper reviews a selection of questions and concepts in this field and demonstrates that they can often be favorably addressed with highly simplified simulation models. Among the topics discussed are membrane adhesion to substrates, mixed lipid bilayers, lipid curvature coupling, pore formation by antimicrobial peptides, composition‐driven protein aggregation, and curvature driven vesiculation.magnified image
Rehabilitation treatment of gait in patients with Parkinson's disease with freezing: A comparison between two physical therapy protocols using visual and auditory cues with or without treadmill training
Authors: Frazzitta Giuseppe , Maestri Roberto , Uccellini Davide , Bertotti Gabriella , Abelli Paola 
Published: April 2009

AbstractFreezing is a disabling symptom in patients with Parkinson's disease. We investigated the effectiveness of a new rehabilitation strategy based on treadmill training associated with auditory and visual cues. Forty Parkinsonian patients with freezing were randomly assigned to two groups: Group 1 underwent a rehabilitation program based on treadmill training associated with auditory and visual cues, while Group 2 followed a rehabilitation protocol using cues and not associated with treadmill. Functional evaluation was based on the Unified Parkinson's Disease Rating Scale Motor Section (UPDRS III), Freezing of Gait Questionnaire (FOGQ), 6‐minute walking test (6MWT), gait speed, and stride cycle. Patients in both the groups had significant improvements in all variables considered by the end of the rehabilitation program (all P = 0.0001). Patients treated with the protocol including treadmill, had more improvement than patients in Group 2 in most functional indicators (P = 0.007, P = 0.0004, P = 0.0126, and P = 0.0263 for FOGQ, 6MWT, gait speed, stride cycle, respectively). The most striking result was obtained for 6MWT, with a mean increase of 130 m in Group 1 compared with 57 m in Group 2. Our results suggest that treadmill training associated with auditory and visual cues might give better results than more conventional treatments. Treadmill training probably acts as a supplementary external cue. © 2009 Movement Disorder Society
De Sitter vacua in simple extended supergravity
Authors: Kehagias A. 
Published: April 2009

AbstractWe show that de Sitter vacua exist in simple extended supergravity theories. In the particular 𝒩 = 2 case we are considering here, we find a de Sitter solution of the supergravity theory with gravity and gravitini turned on by taking into account ψ4 torsion terms.
Higher order conformal perturbation theory
Authors: Schmidt‐Colinet C. 
Published: April 2009

AbstractWe consider a string stretched between two diagonal branes on a bosonic torus under a perturbation of one of the radii. In the world‐sheet description, this corresponds to a perturbation of a conformal field theory with two boundary components. A term in the second order boundary RG equations is related to the change of conformal dimension of the boundary changing operator.
On the tripartite entanglement of three qubits and the entropy of STU black holes
Authors: Rubens W. 
Published: April 2009

AbstractWe show how the entropy of STU black holes is given by the same formula as the tripartite entanglement of three qubits. We explore this link and provide a possible explanation in terms of the wrapping of D3 branes that construct the black holes. This construction also allows us to identify the five parameter generating solution of black holes with a similar one for the qubits.
Nonlinear carrier recombination and transport features in highly excited InN layer
Authors: Nargelas Saulius , Malinauskas Tadas , Kadys Arūnas , Dimakis Emmanouil , Moustakas Theodore D. , Jarašiuūnas Kęstutis 
Published: April 2009

AbstractA time‐resolved picosecond four‐wave mixing, or transient grating technique has provided novel features of non‐equilibrium carrier recombination and diffusion in wide excitation and temperature range of InN (n0 = 1.4×1018 cm–3) at interband photoexcitation (hν = 1.17 eV). Monitoring of the spatial and temporal carrier dynamics via light diffraction provided a direct way to control the dynamics of photoexcited carrier density N (i.e. integrated over the sample depth) in 5×1017 – 5×1019 cm–3 range. The determined bipolar carrier diffusion coefficient 2 cm2/s and its temperature dependence were used for numerical fitting of carrier in‐depth temporal profiles in non‐homogeneously photoexcited InN layers. The recombination rate was found strongly nonlinear: it followed the 1/τR ∝ B*(n0+N) law and was nearly independent on temperature in T = 15 – 300 K range. These features allowed us to suggest a trap‐assisted Auger recombination being the dominant recombination mechanism in InN. The modelling provided a value of trap–assisted Auger recombination coefficient B* = CTAANT = 8×10–10 cm3 s–1. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Silicon electroluminescent device production via plasma ion implantation
Authors: Bradley Michael P. , Desautels Phillip R. , Hunter Darren , Risch Marcel 
Published: April 2009

AbstractWe discuss the technique of plasma ion implantation (PII) and the type of luminescent centers which can be produced by it. We have focused on high‐dose ion implantation into silicon for bandstructure modification. We have produced electroluminescent silicon using a range of plasma ion species including H+, C+, N+ and a range of ion implant conditions. Analyses of the spectra of electroluminescent centers produced by this technique have been performed. Further work will be required to determine the exact physical mechanisms responsible for these effects. Future prospects for electroluminescent devices based on these effects will be discussed. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Prospects for band gap engineering by plasma ion implantation
Authors: Risch Marcel , Bradley Michael P. 
Published: April 2009

AbstractThe suitability of plasma ion implantation (PII) for band gap engineering will be examined by calculations of the band gap's spatial variation. Plasma Ion Implantation is a method to modify the surface and subsurface properties of materials; the ions surrounding the target are forced into all plasma exposed surfaces simultaneously by virtue of high‐voltage pulses. We calculated the fluence and the ion energy distribution from the dynamic sheath model. The distribution of the ions within the target is subsequently simulated by the TRIDYN software. The concentration profiles are converted into a spatial variation of the band gap. The challenges inherent to the method are discussed by means of the examples of carbon (C) PII in silicon (Si) as well as nitrogen (N) PII in gallium arsenide (GaAs). The ion distribution within the material of the former example is suitable for the formation of the Si‐C alloy. On the other hand, the distribution of N ions in GaAs prevents the formation of the Ga‐As‐N alloy. The discussed methods could be a powerful tool for the prediction of materials properties from the plasma processing parameters, thus helping to design materials. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Near‐infrared inorganic/organic hybrid optical upconverter with an embedded mirror
Authors: Chen Jun , Ban Dayan , Feng Xiaodong , Lu Zhenghong , Fathololoumi Saeed , Thorpe Anthony J. Spring , Liu H. C. 
Published: April 2009

AbstractWe report a hybrid organic‐inorganic optical upconverter with an embedded metal mirror. The device was fabricated through direct tandem integration of an organic light emitting diode (OLED) with an inorganic InGaAs/InP photodetector, converting 1.5 μm infrared light to visible light. It was found that the device with an embedded mirror exhibited a low turn‐on voltage (∼3.2 V) and an enhanced efficiency. The ratio of photocurrent‐induced with an input power density of 0.67 mW/mm2 versus dark‐current‐induced visible light was over 500 at a device bias of 6 V at room temperature. The results show that the embedded mirror at the inorganic‐organic interface plays a vital role in the performance enhancement of a hybrid upconverter. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Modeling of dielectric response of GexSbyTez (GST) materials
Authors: Franta Daniel , Necas David , Frumar Miloslav 
Published: April 2009

AbstractThe models of dielectric response of disordered solids based on parametrization of density of states (PDOS) and parametrization of joint density of states (PJDOS) are discussed in detail for interband and intraband transitions. These models are compared with classical models, i. e. Lorentz, Tauc‐Lorentz and Drude. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Novel long fiber Bragg grating fabrication technique based on push‐pull phase‐shifting interferometry
Authors: Gagné Mathieu , Bojor Lucian , Maciejko Romain , Kashyap Raman 
Published: April 2009

AbstractWe demonstrate a novel UV‐writing technique for fabricating long fiber Bragg gratings (FBGs). The use of electro‐optical phase modulators allows the creation of a continuously moving fringe pattern which can be synchronized with a moving fiber. It is shown that infinitely long FBGs may be fabricated using this technique. Preliminary results are presented. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Third‐order optical nonlinearity of β‐carotene homologues
Authors: Fujiwara Masazumi , Yamauchi Kensei , Sugisaki Mitsuru , Yanagi Kazuhiro , Gall Andrew , Robert Bruno , Cogdell Richard J. , Hashimoto Hideki 
Published: April 2009

AbstractWe investigate the third‐order nonlinear optical property of a range of β‐carotene homologues, which have different numbers (n) of conjugated C=C double bonds from n = 7 to 15, by using third‐harmonic generation Maker fringe technique. The results clearly show that there is a remarkable enhancement of the third‐order optical nonlinearity when n = 15, which is a four fold increase compared with n = 11 (i.e. β‐carotene). (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optical properties of conductive ZnO films near infrared frequency
Authors: Itoh T. , Matsuyama K. , Shimakawa K. , Orava J. , Wagner T. , Frumar M. 
Published: April 2009

AbstractTo know the optical constants, n and k, in transparent conductive zinc oxide (ZnO) films, both spectroscopic ellipsometry (SE) and reflectance‐transmittance (RT) method have been adopted. The optical constants, n and k deduced from the SE are different from those estimated from the RT method. We will discuss these differences through the deduced physical parameters in magnetron sputtered Ga‐doped ZnO films. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)