bluuebunny/crossref_metadata_2025 huggingface dataset:
Monoamniotic twin pregnancy discordant for lethal open cranial defect: management dilemmas
Authors: Sepulveda Waldo , Wong Amy E. , Sandoval Rodrigo , Aiello Horacio , Otaño Lucas
Published: March 2011

Objective

To report the sonographic findings, prenatal courses, and management options in four cases of monoamniotic twin pregnancy complicated by a discordant, lethal open cranial vault defect.

Methods

Cases were collected from two Latin American fetal medicine referral centers after the sonographic detection of a monoamniotic twin pregnancy in which one fetus was structurally normal and the other had a lethal open cranial vault defect. Three abnormal fetuses had acrania‐anencephaly sequence and one had a large occipital encephalocele. The diagnosis was confirmed at referral, at which time umbilical cord entanglement was also diagnosed with color Doppler ultrasound in all cases.

Results

Two cases were managed with selective termination, one of which required referral to a fetal surgery center abroad because this option was illegal in Chile. The other case underwent radiofrequency ablation of the fetal intra‐abdominal umbilical vessels after the corresponding ethics and legal committees approved the procedure. In both cases, the non‐anomalous twin was born after 35 weeks and had no perinatal complications. Expectant management was performed in the other two cases, resulting in the death of the normal twin at 25 weeks.

Conclusions

Monoamniotic twin pregnancy discordant for severe cranial vault defect is a serious condition with a high risk of fetal demise of the structurally normal fetus. Our experience, although limited, suggests that aggressive management with selective termination of the abnormal twin and transection of its umbilical cord in these cases may prevent the demise of the structurally normal co‐twin. Copyright © 2011 John Wiley & Sons, Ltd.
Effect of the nucleophilicity and solvent on the chemical modification of flexible poly(vinyl chloride) by substitution
Authors: Kameda Tomohito , Fukuda Yuuzou , Grause Guido , Yoshioka Toshiaki
Published: March 2011

The chemical modification might become an alternative to the thermal degradation of waste polyvinylchloride (PVC). Therefore, the nucleophile substitution of chlorine from flexible PVC by hydroxide (OH−), thiocyanate (SCN−), azide (N3−), and iodide (I−) was investigated in ethylene glycol (EG) at 190°C. With the exception of I−, all nucleophiles used resulted in substitution yields of about 20%. However, also high elimination yields were observed. When SCN was used as the nucleophile, the substitution/elimination ratio increased with decreasing temperature. The product at 150°C contained a mixed structure of thiocyanate and isothiocyanate groups, while at 190°C, only the structure of isothiocyanate was present the product, due to the isomerization of the SCN group under the formation of NCS at elevated temperatures. The substitution and dehydrochlorination yields increased with an increasing molar SCN/Cl ratio. When EG was replaced by diethylene glycol (DEG) or triethylene glycol (TEG), the dehydrochlorination was found to proceed more rapidly. The use of a solvent with a lower polarity improved the contact between the solvent and the polymer; however, solvents with a lower polarity favor the elimination over the substitution. Therefore, the substitution–elimination ratio increased in the order EG > DEG > TEG. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers.
Effects of carbon nanotubes and their state of dispersion on the anionic polymerization of ε‐caprolactam: II. Rheology
Authors: Penu Christian , Hu Guo‐Hua , Fonteix Christian , Marchal Philippe , Choplin Lionel , Feng Lian‐Fang
Published: March 2011

A rheometer‐reactor was designed to study the effect of the presence of multiwalled‐carbon nanotubes (MWCNT) on the kinetics of the activated anionic polymerization of ε‐caprolactam (AAPCL). The presence of the MWCNT slowed down the kinetics of the AAPCL. Moreover, the higher the MWCNT content, the more important its adverse effect on the kinetics of the AAPCL. On the other hand, the presence of the MWCNT could also adversely affect the molar mass of the resulting polyamide 6 when its content was high enough (about 1.0 wt % or higher). Possible mechanisms are discussed. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers.
Electrospinning of polyacrylonitrile solutions containing diluted sodiumthiocyanate
Authors: Moon SungCheal , Choi JaeKon , Farris Richard J.
Published: March 2011

The effect of NaSCN salt on the spinnability of polyacrylonitrile (PAN) solutions, its resulting morphology, mechanical property, and the flame resistance of the resulting electrospun nanofibers were studied. The intent was to develop a method to produce nanosized carbon fiber precursors with good properties. Electrospun PAN nanofibers from 9.7–9.9 wt% PAN/sodiumthiocyanate (NaSCN) (aq)/Dimethylformamide (DMF) solutions with 1.0–2.9 wt% NaSCN (aq), and 10–15 wt% PAN/DMF solutions without salt exhibited good spinnability and morphology with no beading in the range of applied voltage (18–20 kV) and take‐up velocity (9.8–12.3 m/s). The relatively high take‐up velocity produced good yarn alignment. The diameter distributions of the PAN nanofibers containing the NaSCN salt were narrower than those of the PAN/DMF nanofibers without the salt. It was determined that the maximum content of salt for production of electrospun PAN nanofibers with good morphology was below 3.8 wt% (40 wt% based on PAN). The salt concentration can positively influence on the narrow diameter distributions of the resulting electrospun fibers. Also, it could be confirmed that the salt effect on mechanical property and flame resistance of electrospun PAN nanofibers. In particular, the elongation of the PAN nanofiber with 2.9 wt% NaSCN (aq) was significantly increased as much as 186% compared with that of 10 wt% PAN nanofiber without the salt. The flame resistance and mechanical properties of the stabilized PAN nanofibers with NaSCN (aq) increased after oxidization process. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers.
Effect of filler addition and strain rate on the compressive strength of silica styrene‐butadiene rubber‐filled epoxy composites
Authors: Gope Prakash Chandra , Singh Vinay Kumar
Published: March 2011

The compressive failure of nanoparticle silica and styrene‐butadiene rubber (SBR)‐filled epoxy composites has been investigated. Significant increase in compressive strength, compressive modulus, work of yielding, and work of fracture was noted for the cases of composites containing low weight fraction of silica and SBR. The compressive strength is about 4–10 times of the tensile strength for composite material containing different weight percent of SBR. Increase in compressive yield strength and decrease in compressive ultimate strength have been observed with crosshead speed 0.1–100 mm/s over all weight content of SBR and silica. The material shows increased elastic region with increasing crosshead speed. This indicates that the material is expected to behave more elastically and less plastically over all the crosshead speeds. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers
Effects of the addition of LiCl, LiClO4, and LiCF3SO3salts on the chemical structure, density, electrical, and mechanical properties of rigid polyurethane foam composite
Authors: Verdolotti L. , Colini S. , Porta G. , Iannace S.
Published: March 2011

The effect of the incorporation of several lithium salts on the electrical and mechanical properties of polyurethane rigid (PUR) foams was investigated. Different amounts of lithium chloride (LiCl), lithium perchlorate (LiClO4), and lithium trifluoromethanesulfonate (LiCF3SO3) were added to the polyuretanic precursor. The salts affected the cellular microstructures and consequently the mechanical properties of the composite. Composite foams containing an amount of LiCl greater than 2 wt% showed low‐surface resistivity (∼106Ω), whereas the LiClO4and LiCF3SO3composites showed, in all range of filler percentage analyzed, high‐surface resistivity values (∼1011Ω). This behavior was related to the different interactions between PUR and lithium salts, as confirmed by FTIR/Attenuated Total Reflectance analysis. Only the LiCl was able to create a motion of the ions Li+and Cl−along the polyurethanic chains, because LiCl was completely dissociated. On the contrary, LiClO4and LiCF3SO3that affected the macromolecular structure of the polymeric network did not permit the formation of polyurethanic channels, where the ions could move, thus creating a charge motion. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers
Visual observation and numerical studies of polymer foaming behavior of polypropylene/carbon dioxide system in a core‐back injection molding process
Authors: Ishikawa Takeshi , Ohshima Masahiro
Published: March 2011

Thermoplastic foaming within a mold cavity was visualized as it was conducted in an 85‐ton core‐back injection‐molding machine. The core‐back molding process moved a section of the mold just after injecting a molten polymer into the cavity, quickly reducing the pressure to enhance the bubble nucleation. The foaming behavior during core‐back was observed directly through the glass windows of the mold. In the experiments, impact copolymer polypropylene was foamed with carbon dioxide. The effects of the gas concentration and the core‐back rate on bubble nucleation and growth were investigated. It was experimentally confirmed that the bubbles disappeared when the cavity was fully packed and that bubble nucleation occurred when the mold plate was moved and the cavity pressure dropped. Faster core‐back rates and higher gas concentrations increased the number of bubbles while decreasing their size. To analyze the experimental results, a bubble nucleation and growth model was employed that was based on batch foaming. The numerical results were a reasonable representation of the experiments, and this study demonstrated the applicability of the conventional free foaming model to the industrial core‐back molding process. Many aspects of the foaming in the core‐back molding aresimilar to the behaviors observed by batch foaming. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers
Novel Ag/C nanocable/epoxy resin composite
Authors: Liang Honglu , Yu Demei
Published: March 2011

Silver/carbon (Ag/C) nanocables were obtained in the presence of cetyltrimethylammonium bromide (CTAB) under hydrothermal conditions in order to modify epoxy resin. Nanocable is a nanocomposite of nanowire (core) wrapped with one or more outer layers (shell). Scanning electron microscopy and energy‐dispersive X‐ray spectroscopy proved that nanocables consist of a silver nanowire core and a carbon outer shell. The (Ag/C)/epoxy composites were prepared by compounding Ag/C nanocables and epoxy resin. An investigation of the thermal, mechanical, and dielectric properties of these composites showed that the thermal stability and dielectric constant of the composites were enhanced. Interestingly, the breakdown strength of the composites at room temperature increased. Normally, breakdown strength decreases when conducting fillers are added. Fracture morphology of the (Ag/C)/epoxy composite also showed increased toughness. The relationship between the properties and microstructure of the composite was discussed in detail to explain the mechanism behind the change in material properties. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers
Impact of hydroquinone on thermal and electrical properties of plasticized [poly(vinyl alcohol)]0.7(LiBr)0.3(H2SO4) solid acid membrane
Authors: Badr Samy , Sheha Eslam
Published: March 2011

A novel multi‐component system containing poly(vinyl alcohol), lithium bromide, sulfuric acid, ethylene carbonate and hydroquinone was prepared using a solution‐casting technique. The presence of hydroquinone as a reducing agent in the inorganic–organic membrane structure thus produced was thought to lead to enhanced thermal stability of the membrane. The activation energy for the thermal decomposition of the product samples increased with increasing hydroquinone doping. The ionic conductivities of the films were determined from AC impedance measurements in the temperature range 300–373 K. The maximum conductivity was found to be 1.75 × 10−3 S cm−1 for a film doped with 4 wt% hydroquinone. The results give some insight into the potential utility of the membrane as a proton‐conducting solid polymer electrolyte. Copyright © 2011 Society of Chemical Industry
Characterization of quaternized chitosan‐stabilized iron oxide nanoparticles as a novel potential magnetic resonance imaging contrast agent for cell tracking
Authors: Shen Chia‐Rui , Wu Shu‐Ting , Tsai Zei‐Tsan , Wang Jiun‐Jie , Yen Tzu‐Chen , Tsai Jin‐Sheng , Shih Mei‐Fen , Liu Chao‐Lin
Published: March 2011

Polymer‐stabilized iron oxide nanoparticles could be used as contrast agents in magnetic resonance imaging (MRI) due to their unique superparamagnetism. Here we demonstrate a quaternized chitosan, i.e. N‐[(2‐hydroxy‐3‐trimethylammonium)propyl] chitosan chloride (HTCC), encapsulating superparamagnetic iron oxide (SPIO), with very low toxicity and less effect on cell growth. HTCC has quaternary amino groups introduced into the chitosan chain, and such modification of chitosan should render it soluble in water. Most importantly, the HTCC–SPIO thus prepared has the ability to accelerate the MRI relaxation processes of surrounding water protons, resulting in enhanced MRI contrast (R2: y = 0.1076x − 0.0092; R1: y = 0.008x − 0.0005). The iron content quantified by Prussian blue staining and MRI revealed a positive correlation between Prussian blue positive cells and the change of MRI signal intensity. Also, transmission electron microscopy and element mapping confirmed intracellular metal‐like spots as internalized iron oxide. Such findings support the use of these quaternized chitosan‐stabilized iron oxide nanoparticles as a potential MRI contrast agent for cell tracking. Copyright © 2011 Society of Chemical Industry
Characterization of high‐efficiency c‐Si CPV cells
Authors: Pravettoni Mauro , Galleano Roberto , Fucci Raffaele , Kenny Robert P. , Romano Antonio , Pellegrino Michele , Aitasalo Tuomas , Flaminio Giovanni , Privato Carlo , Zaaiman Willem , Dunlop Ewan D.
Published: March 2011

Concentrating photovoltaics (CPV) represent an emerging market at its early stage for terrestrial application with large growth expectation and considerable research activity on new cell production has been conducting recently. In response to a fast growing demand for traceable and independent measurements on CPV cells and systems the European Solar Test Installation (ESTI) has started a research program on indoor/outdoor devices characterization. This paper focuses on two essential components of device calibration. Calibration requires traceable calibrated reference devices: for this purpose reference c‐Si cells equipped with neutral density filters of various optical densities have been used at ESTI for checking device linearity at different concentration ratios. Also essential is the implementation of common procedures and intercomparison of test results at different test laboratories. Procedures and experimental setups for concentrating c‐Si cell characterization at both ESTI and at the UTTP FOTO Laboratory of ENEA are described and results of an intercomparison are presented and discussed. Electrical performance measurements have been performed at high intensities on three different setups: a recently developed 1500× pulsed solar simulator at ESTI and two modified solar simulators capable of achieving up to 250× concentration at ENEA. Reported results show agreement within measurement uncertainties of the electrical parameters. Copyright © 2011 John Wiley & Sons, Ltd.
Inkjet printed metallizations for Cu(In1−xGax)Se2 photovoltaic cells
Authors: Hersh Peter A. , Curtis Calvin J. , van Hest Maikel F.A.M. , Kreuder John J. , Pasquarelli Robert , Miedaner Alex , Ginley David S.
Published: March 2011

This study reports the inkjet printing of Ag front contacts on Aluminum doped Zinc Oxide (AZO)/intrinsic Zinc Oxide (i‐ZnO)/CdS/Cu(In1−xGax)Se2 (CIGS)/Mo thin film photovoltaic cells. The printed Ag contacts are being developed to replace the currently employed evaporated Ni/Al bi‐layer contacts. Inkjet deposition conditions were optimized to reduce line resistivity and reduce contact resistance to the Al:ZnO layer. Ag lines printed at a substrate temperature of 200°C showed a line resistivity of 2.06 µΩ · cm and a contact resistance to Al:ZnO of 8.2 ± 0.2 mΩ · cm2 compared to 6.93 ± 0.3 mΩ · cm2 for thermally evaporated contacts. These deposition conditions were used to deposit front contacts onto high quality CIGS thin film photovoltaic cells. The heating required to print the Ag contacts caused the performance to degrade compared to similar devices with evaporated Ni/Al contacts that were not heated. Devices with inkjet printed contacts showed 11.4% conversion efficiency compared to 14.8% with evaporated contacts. Strategies to minimize heating, which is detrimental for efficiency, during inkjet printing are proposed. Copyright © 2011 John Wiley & Sons, Ltd.
Synthesis and properties of biobased epoxy resins. part 1. Glycidylation of flavonoids by epichlorohydrin
Authors: Nouailhas Hélène , Aouf Chahinez , Le Guerneve Christine , Caillol Sylvain , Boutevin Bernard , Fulcrand Hélène
Published: March 2011

Biobased epoxy resins were synthesized from a catechin molecule, one of the repetitive units in natural flavonoid biopolymers also named condensed tannins. The reactivity of catechin toward epichlorohydrin to form glycidyl ether derivatives was studied using two model compounds, resorcinol and 4‐methylcatechol, which represent the A and B rings of catechin, respectively. These model molecules clearly showed differences in reactivity upon glycidylation, explaining the results found with catechin monomer. The reaction products were characterized by both FTIR and NMR spectroscopy and chemical assay. The glycidyl ether of catechin (GEC) was successfully cured in various epoxy resin formulations. The GECs thermal properties showed that these new synthesized epoxy resins displayed interesting properties compared to the commercial diglycidyl ether of bisphenol A (DGEBA). For instance, when incorporated up to 50% into the DGEBA resin, GEC did not modify the glass‐transition temperature. Epoxy resins formulated with GEC had slightly lower storage moduli but induced a decrease of the swelling percentage, suggesting that GEC‐enhanced crosslinking in the epoxy resin networks. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Synthesis, self‐assembly, fluorescence, and thermosensitive properties of star‐shaped amphiphilic copolymers with porphyrin core
Authors: Ren Tianbin , Wang An , Yuan Weizhong , Li Lan , Feng Yue
Published: March 2011

Star‐shaped amphiphilic poly(ε‐caprolactone)‐block‐poly(oligo(ethylene glycol) methyl ether methacrylate) with porphyrin core (SPPCL‐b‐POEGMA) was synthesized by combination of ring‐opening polymerization (ROP) and atom transfer radical polymerization (ATRP). Star‐shaped PCL with porphyrin core (SPPCL) was prepared by bulk polymerization of ε‐caprolactone (CL) with tetrahydroxyethyl‐terminated porphyrin initiator and tin 2‐ethylexanote (Sn(Oct)2) catalyst. SPPCL was converted into SPPCLBr macroinitiator with 2‐bromoisobutyryl bromide. Star‐shaped SPPCL‐b‐POEGMA was obtained via ATRP of oligo(ethylene glycol) methyl ether methacrylate (OEGMA). SPPCL‐b‐POEGMA can easily self‐assemble into micelles in aqueous solution via dialysis method. The formation of micellar aggregates were confirmed by critical micelle formation concentration, dynamic light scattering, and transmission electron microscopy. The micelles also exhibit property of temperature‐induced drug release and the lower critical solution temperature (LCST) was 60.6 °C. Furthermore, SPPCL‐b‐POEGMA micelles can reversibly swell and shrink in response to external temperature. In addition, SPPCL‐b‐POEGMA can present obvious fluorescence. Finally, the controlled drug release of copolymer micelles can be achieved by the change of temperatures. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
A snapshot of the expression signature of androgen receptor splicing variants and their distinctive transcriptional activities
Authors: Hu Rong , Isaacs William B. , Luo Jun
Published: March 2011

BACKGROUND

The diversity and complexity of the human androgen receptor (AR) splicing variants are well appreciated but not fully understood. The goal of this study is to generate a comprehensive expression signature of AR variants in castration‐resistant prostate cancer (CRPC), and to address the relative importance of the individual variants in conferring the castration‐resistant phenotype.

METHODS

A modified RNA amplification method, termed selective linear amplification of sense RNA, was developed to amplify all AR transcripts containing AR exon 3 in CRPC specimens, which were profiled using tiling expression microarrays. Coding sequences for the AR variants were cloned into expression vectors and assessed for their transcriptional activities. Quantitative RT‐PCR was used to determine their in vivo expression patterns in an expanded set of clinical specimens.

RESULTS

In addition to expression peaks in AR intron 3, a novel AR exon, termed exon 9, was discovered. Exon 9 was spliced into multiple novel AR variants. Different AR splicing variants were functionally distinctive, with some demonstrating constitutive activity while others were conditionally active. Conditionally active AR‐Vs may activate AR signaling depending on the cellular context. Importantly, AR variant functions did not appear to depend on the full‐length AR.

CONCLUSIONS

This study provided the first unbiased snapshot of the AR variant signature consisting of multiple AR variants with distinctive functional properties, directly in CRPC specimens. Study findings suggest that the aggregate function of multiple AR variants may confer a castration‐resistant phenotype independent of the full‐length AR. Prostate 71:1656–1667, 2011. © 2011 Wiley‐Liss, Inc.
Medicine shortages as a result of parallel exporting to Europe
Authors: Chaplin Steve
Published: March 2011

Steve Chaplin explains how shortages of certain medicines have arisen as a result of parallel exporting of drugs from the UK to Europe. Copyright © 2011 Wiley Interface Ltd
Aluminum nitride grown on lens shaped patterned sapphire by hydride vapor phase epitaxy
Authors: Bryant Benjamin N. , Kamber Derrick S. , Wu Feng , Nakamura Shuji , Speck James S.
Published: March 2011

Thick c‐plane aluminum nitride (AlN) films were grown directly onto lens shaped patterned c‐plane sapphire substrates by hydride vapor phase epitaxy (HVPE). The sapphire patterning consisted of convex hemispherical lenses in a hexagonal pattern. These films were fully coalesced, planar, colorless, specular and up to 20 μm thick. Full widths at half maximum of X‐ray rocking curves for the on‐axis (0002) and off‐axis (20$ \bar 2 $1) AlN reflections for fully coalesced films reached 914 and 1502 arcsec respectively. Plan view transmission electron microscopy was used to determine the threading dislocation density which was ∼8 x 108 cm‐2. An interrupted growth series was also performed to evaluate the growth evolution of the AlN. Scanning electron microscopy was used to examine the initial growth and coalescence of the films. The AlN was determined to grow in hexagonal pillars initiated on the lenses, eventually coalescing together. These AlN films offer a promising substrate for AlGaN based UV optoelectronics thanks to both its transparency in the UV region and patterning effects. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Growth of bulk GaN crystals by Na flux method
Authors: Mori Y. , Kitaoka Y. , Imade M. , Miyoshi N. , Yoshimura M. , Sasaki T.
Published: March 2011

High‐quality and low cost bulk crystals are needed in the field of group III nitride semiconductors in order to develop optical and electrical devices. There are two approaches for the growth of bulk GaN crystal by the Na flux method. One is to grow thick GaN crystal on a seed GaN crystal grown by vapour phase method. The other one is to grow GaN crystal on the seed GaN crystal obtained by spontaneous nucleation. The both methods show advantages and disadvantages, respectively. We also present the effects of the flux composition on the growth habit and the growth rate for fabrication of boule‐shape bulk GaN crystals. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Microstructural analysis of thick AlGaN epilayers using Mg‐doped AlN underlying layer
Authors: Nonaka K. , Asai T. , Ban K. , Yamamoto J. , Iwaya M. , Takeuchi T. , Kamiyama S. , Akasaki I. , Amano H. , Wu Z. H.
Published: March 2011

This paper reports the microstructural analysis of 20‐μm‐thick Al0.5Ga0.5N with improved crystalline quality owing to the use of a Mg‐doped AlN underlying layer. The threading dislocation density in 20‐μm‐thick Al0.5Ga0.5N on Mg‐doped AlN was 8.6×108cm‐2, which is about one‐fifth lower than that of Al0.5Ga0.5N on an undoped AlN underlying layer. The microstructural analysis was carried out to clarify dislocation behaviours in the Al0.5Ga0.5N layer on the Mg‐doped AlN underlying layer. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Fabrication of AlN single crystal particles by a chemical vapor method using aluminum chloride
Authors: Mori Tatsuhiro , Kobayashi Takayoshi , Kawanishi Yasumasa , Kominami Hiroko , Nakanishi Yoichiro , Hara Kazuhiko
Published: March 2011

The synthesis of single crystal AlN particles has been carried out by the chemical vapor method using AlCl3 and NH3 as sources at 1450 °C. The x‐ray diffraction (XRD) measurement reveals that the samples are AlN in the wurtzite structure. The XRD line width had its minimum around partial pressure of NH3 (P (NH3)) of 0.25 atm, indicating the highest crystal quality among the samples synthesized in this study. The powders prepared at P (NH3) between 0.13 and 0.38 atm consisted mostly of particles with sizes ranging between approximately 100 and 500 nm. The particles in these samples had specific shapes with a sixfold symmetry reflecting the wurtzite crystal structure of AlN. The observation of particle morphology has also suggested that the particles composed of two crystal grains are included in the samples. The mechanism of particle formation was discussed based on the dependence of particle morphology on P (NH3). Comparison with the synthesis using vaporized Al as an Al source leads us to conclude that the use of AlCl3 is essential to the efficient formation of single crystal particles. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
In situ measurement of adsorbed nitrogen atoms for PA‐MBE growth of group III nitrides on Si
Authors: Ohachi Tadashi , Yamabe Nobuhiko , Yamamoto Yuka , Wada Motoi , Ariyada Osamu
Published: March 2011

An atom probe of two parallel electrodes is proposed to monitor adsorbed (ADS) nitrogen atoms in situ during growth of β‐Si3N4 using indirect exposure of effusing active nitrogen beam from the radio frequency induction coupled plasma cell. The β‐Si3N4 film is a component of a double buffer layer (DBL) AlN(0001)/β‐Si3N4/Si(111) to grow high quality the group III nitrides and their alloys on Si. Atom current between the parallel electrodes corresponds to flux of the ADS nitrogen atoms on the inside surface at the atom potential, VA. The ADS atom current received influence of wall and shutter of the cell, because adsorption of nitrogen atom depended wall condition such as temperature and the concentration of adatoms on the wall (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Improving GaN‐on‐silicon properties for GaN device epitaxy
Authors: Dadgar A. , Hempel T. , Bläsing J. , Schulz O. , Fritze S. , Christen J. , Krost A.
Published: March 2011

GaN growth on silicon has recently found its way into products as transistor devices for high frequencies and high‐voltage applications as well as for light emitting diodes (LEDs). Here, we present the importance of high quality GaN layers for growing LED structures and high‐voltage transistors on silicon. The major difference is that LED growth on silicon substrates suffers from edge type dislocations during silicon doping while FETs suffer from a lowered breakdown field. We will show that the latter is most likely originating in screw type dislocations. By optimizing GaN material quality the breakdown field strength can be doubled from less than 0.7x106 V/cm up to ∼ 1.5x106 V/cm. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Investigation of InN mole fraction fluctuation in InGaN films grown by RF‐MBE
Authors: Kimura Takuya , Fukumoto Eita , Yamaguchi Tomohiro , Wang Ke , Kaneko Masamitsu , Araki Tsutomu , Yoon Euijoon , Nanishi Yasushi
Published: March 2011

We use cathodoluminescence (CL) mapping and Kelvin probe force microscopy (KFM) to investigate fluctuations of the InN mole fraction in InGaN films grown by radio‐frequency plasma‐assisted molecular beam epitaxy. Both techniques reveal that InGaN films on GaN templates with scratches exhibit clear composition fluctuations. CL spectra of InGaN obtained in scanning mode have two peaks. Monochromatic CL maps at these two peaks reveal a clear contrast between flat regions and scratches. The shorter‐wavelength CL peak is from scratched regions and the longer‐wavelength peak is from flat regions. These results reveal that less In is incorporated in scratched regions than in flat regions. KFM measurements reveal that scratched and flat regions have different surface potentials. Experiments on a series of InGaN films with InN mole fractions that span the entire composition range confirm that the surface potential of InGaN depends on the In content. This demonstrates that KFM is useful for studying microscale fluctuations in the InN mole fraction in InGaN. A possible mechanism for this fluctuation is discussed. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The Antiangiogenic and Antinociceptive Activities of n‐Propyl Gallate
Authors: Jung H‐J. , Lim C‐J.
Published: March 2011

n‐Propyl gallate dose‐dependently displayed an inhibitory effect on chick chorioallantoic membrane (CAM) angiogenesis. It markedly increased the endostatin level in both isolated CAM tissues and human umbilical vein endothelial cells (HUVECs). n‐Propyl gallate was also able to enhance the endostatin mRNA level in HUVECs. Antinociceptive activity of n‐propyl gallate was assessed using an acetic acid‐induced writhing test in mice. In brief, n‐propyl gallate possesses antiangiogenic activity via up‐regulation of endostatin. Copyright © 2011 John Wiley & Sons, Ltd.
Bakuchicin induces Vascular Relaxation via Endothelium‐dependent NO‐cGMP Signaling
Authors: Li Xiang , Lee Yun Jung , Kim Youn Chul , Jeong Gil Saeng , Cui Hao Zhen , Kim Hye Yoom , Kang Dae Gill , Lee Ho Sub
Published: March 2011

Bakuchicin is a furanocoumarin derived from the seeds of Psoralea corylifolia. The aim of the present study was to investigate the effect of bakuchicin on vascular tone in rat aortic tissue. Bakuchicin induced a dose‐dependent relaxation of phenylephrine‐precontracted rat aorta which was abolished by removal of the endothelium. Pretreatment of the endothelium‐intact aortic tissues with NG‐nitro‐ l‐arginine methylester (L‐NAME) or 1H‐[1,2,4]‐oxadiazole‐[4,3‐α]‐quinoxalin‐1‐one (ODQ) significantly inhibited the vascular relaxation induced by bakuchicin. Incubation with bakuchicin increased the production of cGMP in a concentration‐dependent manner, and this effect was blocked by pretreatment with both L‐NAME and ODQ. Vascular relaxation induced by bakuchicin was significantly inhibited by pretreatment with verapamil and diltiazem, but not by several other inhibitors including tetraethylammonium (TEA), glibenclamide, indomethacin, atropine or propranolol. These results suggested that bakuchicin‐induced vasodilatation is closely associated with the endothelium‐dependent nitric oxide (NO)/cGMP signaling pathway, with the possible involvement of L‐type Ca2+channels. Copyright © 2011 John Wiley & Sons, Ltd.
Nonlinear shallow‐water equations on the Yin‐Yang grid
Authors: Qaddouri Abdessamad
Published: March 2011

The system of nonlinear shallow‐water equations (SWEs) is a hyperbolic system serving as a primary test problem for numerical methods used in modelling global atmospheric flows. In this article, the SWEs on a rotating sphere are solved on the Yin‐Yang grid by using a domain decomposition method (DDM). This overset grid is singularity free and has a quasi‐uniform grid spacing. It is composed of two identical latitude/longitude orthogonal grid panels that are combined to cover the sphere with partial overlap on their boundaries. On each of the two subgrids, the local solver is based on an implicit and semi‐Lagrangian discretization on a horizontally staggered Arakawa C mesh. The resulting positive definite Helmholtz problem is solved using a Schwarz‐type DDM known as the optimized Schwarz method, which gives better performance than the classical Schwarz method by using specific Robin or higher‐order transmission conditions. Finally, the standard shallow‐water test set is performed in order to show that the DDM solution for SWEs on the Yin‐Yang grid system can reproduce the global solution accurately on the sphere. This work represents a first step in the development of a three‐dimensional forecasting model on the Yin‐Yang grid. © 2011 Crown in the right of Canada. Published by John Wiley & Sons Ltd.
Design of a contact probe with high positioning accuracy for plasmonic lithography
Authors: Jang Jinhee , Kim Yongwoo , Kim Seok , Jung Howon , Hahn Jae Won
Published: March 2011

Plasmonic lithography with a contact probe records nano‐meter scale features and has high‐throughput owing to its capability to scan in contact mode. The probe is commonly based on a micrometer‐scale cantilever, which leads to the tip‐positioning problem due to force‐deflection that induces lateral tip displacement. We propose a geometrically modified probe to achieve high positioning accuracy. Contrary to a conventional cantilever‐tip probe, we designed a “circular probe” with arc‐shaped arms that hold the tip in the center. The mechanism is based on the “fixed‐fixed beam” concept in material mechanics. To confirm its positioning accuracy, we used a finite element method (FEM) to calculate the tip displacement for a circular probe and compared the results with those using a conventional cantilever‐tip probe. The probe was designed considering a silicon‐based micro‐fabrication process. The designed probe has a square outline boundary with a length of 50 µm, four arms, and a pyramidal tip with a height of 5 µm. The ratio of the lateral tip displacement to the vertical deflection was evaluated to indicate the accuracy of the probe. The probe has higher positioning accuracy by a factor of 103 and 10 in its approach mode and scan mode, respectively, compared with a cantilever‐tip probe. We expect that the probe is suitable for the applications that require high positioning accuracy, such as nanolithography in contact mode and applications based on multiple‐probe arrays. SCANNING 33: 99–105, 2011. © 2011 Wiley Periodicals, Inc.
Aktuelle Entwicklungen in der Züchtungstechnologie von CZ‐Si‐Kristallen
Authors: Altekrüger Burkhard , Fisahn Gert
Published: March 2011

Die Idee der Einführung einer neuen Wafer Generation mit größerem Durchmesser wird in der Halbleiter und Mikroelektronik‐Industrie hauptsächlich aus der Sicht der Betreiber der großen Fertigungslinien diskutiert und vorangetrieben, die hieraus einen Produktivitäts‐Gewinn und Kostenvorteil in der Chipfertigung erwarten. Die prozesstechnischen Anforderungen bei der Züchtung von großen Si‐Kristallen mit Durchmessern von 300mm und 450mm bedeuten erhebliche Anforderungen und Herausforderungen an die dafür geeignete Anlagen‐Technologie. Diese neuen Anforderungen sind mit einem einfachen „Upgrade”︁ der bisherigen Anlagentechnik nicht zu erfüllen. Daher ist die Neuentwicklung einer Anlagen‐Generation für 300mm und 450mm Si‐ Kristalle erforderlich, die sich durch ihre Grundkonzeption wie ihres statischen Aufbaus sowie des Anlagen und Komponenten‐Handlings von ihren Vorgängergenerationen unterscheidet. Erfahrungen bei der Anlagenentwicklung für 450mm Wafer liegen bei der PVA TePla bereits vor.
Safety Measures During Cholecystectomy: Results of a Nationwide Survey
Authors: Buddingh K. T. , Hofker H. S. , ten Cate Hoedemaker H. O. , van Dam G. M. , Ploeg R. J. , Nieuwenhuijs V. B.
Published: March 2011

Background

This study aimed to identify safety measures practiced by Dutch surgeons during laparoscopic cholecystectomy.

Method

An electronic questionnaire was sent to all members of the Dutch Society of Surgery with a registered e‐mail address.

Results

The response rate was 40.4% and 453 responses were analyzed. The distribution of the respondents with regard to type of hospital was similar to that in the general population of Dutch surgeons. The critical view of safety (CVS) technique is used by 97.6% of the surgeons. It is documented by 92.6%, mostly in the operation report (80.0%), but often augmented by photography (42.7%) or video (30.2%). If the CVS is not obtained, 50.9% of surgeons convert to the open approach, 39.1% continue laparoscopically, and 10.0% perform additional imaging studies. Of Dutch surgeons, 53.2% never perform intraoperative cholangiography (IOC), 41.3% perform it incidentally, and only 2.6% perform it routinely. A total of 105 bile duct injuries (BDIs) were reported in 14,387 cholecystectomies (0.73%). The self‐reported major BDI rate (involving the common bile duct) was 0.13%, but these figures need to be confirmed in other studies.

Conclusion

The CVS approach in laparoscopic cholecystectomy is embraced by virtually all Dutch surgeons. The course of action when CVS is not obtained varies. IOC seems to be an endangered skill as over half the Dutch surgeons never perform it and the rest perform it only incidentally.
Absent Bodies: The AIDS Memorial Quilt as Social Melancholia
Authors: GAMBARDELLA STEVEN JAMES
Published: March 2011

Far from being apolitical, self-indulgent or ineffective, as was suggested by some in the activist community, the NAMES Project Quilt became a symbol of the decimation of AIDS and a beacon for those in the AIDS-affected community, and challenged and transformed public attitudes towards people with AIDS. The NAMES Project Quilt risked sanitizing and homogenizing the particularities of the deceased, but I shall argue that the spectacle of the quilt changed public opinion through its mechanisms of publicity and meaning-making. Building on Michael Warner's notion of the ‘Mass Subject’, the quilt, I will suggest, transformed the mainstream, effectively forcing the formerly abject AIDS-affected community into public consciousness through the mechanisms of mass media.
General Ricci and the Suppression of the Jesuit Order in France 1760–4
Authors: Thompson D. G.
Published: March 2011

The issue in the series of crises leading to the suppression of the Jesuit order in France in 1764 was the absolute obedience owed under the Jesuit Institute by every French Jesuit to the superior general of the Society of Jesus resident in Rome. On the eve of the suppression, the French law courts and the Crown reasoned that Jesuit subjects of the king of France ought not to owe such obedience to a foreign superior living on foreign soil. In the eyes of the secular authorities, the French Jesuits' connection with their superior general constituted a threat to the security of the French state. Initially, most French Jesuit leaders accepted this point of view and tried to come to an accommodation with the state which would have loosened their ties to the general.
John Ponet in Exile: a Ponet Letter to John Bale
Authors: Baskerville E. J.
Published: March 2011

Though the political ideas of JohnPonet, Edwardian bishop and Marian exile, continue to attract interest, the facts of Ponet's life and, especially, of his activities during his years of exile have excited no high degree of scholarly attention since the works of Christina Garrett and Winthrop S. Hudson. Yet one piece of evidence, unknown to both Garrett and Hudson, exists that tells us a few important things about his attitude toward and, particularly, his involvement in, the propaganda and polemical activities of Protestant exiles under Mary. The evidence in question is a letter from Ponet in Strasbourg to John Bale ‘at Frankfurt’; and since this document has appeared to date only in excerpts, it will be well to begin by offering a complete transcription of it.
Divided between Heart and Mind: the Critical Period for Protestant Thought in America
Authors: Hart D. G.
Published: March 2011

In 1854, Philip Schaff, professor of church history at Mercersburg Theological Seminary and minister of the German Reformed Church, reported to his denomination on the state of Christianity in America. Although the American Church had many shortcomings, according to Schaff the United States was ‘by far the most religious and Christian country in the world’. Many Protestant leaders, however, took a dimmer view of Christianity's prospects. In the middle decades of the nineteenth century, a nagging sense prevailed that traditional theology was no longer capable of integrating religion and culture, or piety and intelligence. Bela Bates Edwards, a conservative New England divine, complained of the prevalent opinion ‘that an intellectual clergyman is deficient in piety and that an eminently pious minister is deficient in intellect’. Edwards was not merely lamenting the unpopularity of Calvinism. A Unitarian writer also noted a burgeoning ‘clerical skepticism’. Intelligent and well-trained men who wished to defend and preach the Gospel, he wrote, ‘find themselves struggling within the fetters of a creed by which they have pledged themselves’. An 1853 Memorial to the Bishops of the Protestant Episcopal Church summed up the doubts of Protestant clergymen when it asked whether the Church's traditional theology and ministry were ‘competent to the work of preaching and dispensing the Gospel to all sorts and conditions of men, and so adequate to do the work of the Lord in this land and in this age’.
The Campaign against The Humble Proposals of 1632
Authors: Polizzotto Carolyn
Published: March 2011

Early in 1652 the leading Independent divine John Owen, with a group of other ministers, published a plan for the reform of the Church entitled The Humble Proposals. The scheme aroused antagonism and opposition. The existence of petitions against it, one of them published by Roger Williams under the title The Fourth Paper (1652), was noted by David Masson in his Life of Milton. The protest was more intense, and went on longer, than Masson suggests. Petitions were soon followed by a number of tracts, some of them anonymous, others raising the issues in an introductory epistle or an appendix to material with a wider reference. Taken together, they clearly indicate a well-organised campaign behind the scenes.
How Shall the Nations Repent? The Stuttgart Declaration of Guilt, October 1945
Authors: Conway John S.
Published: March 2011

The Stuttgart Declaration of Guilt, issued by the leaders of the German Evangelical (i.e. Protestant) churches in October 1945, was a unique document in the recent history of the Christian Churches. This public acknowledgement of responsibility and guilt for their inadequate response to the criminal actions of the nation's political leaders was, and remains, unprecedented. The solemn proclamation included the by-now well-known sentences:

With great pain do we say: through us endless sufferings have been brought to many peoples and nations. What we have often borne witness to before our congregations, we now declare in the name of the whole church. We have for many years struggled in the name of Jesus Christ against the spirit which found its terrible expression in the National Socialist regime of tyranny, but we accuse ourselves for not witnessing more courageously, for not praying more faithfully, for not believing more joyously and for not loving more ardently.
‘For the Increase of Divine Service’: Chantries in the Parish in Late Medieval Bristol
Authors: Burgess Clive
Published: March 2011

While it is incontrovertible that the Catholic faith exercised a profound influence on the lives of the common people of fifteenth-century England, it is equally apparent that many aspects of contemporary belief and practice will never be wholly clear. This is not simply for want of evidence but more the result of the limitations of the sources. It may, for instance, be assumed that contemporaries' religious priorities would be illuminated by close examination of their wills since these documents almost invariably deal with pious provisions intended to benefit testators' souls. But tolerably represented by surviving wills as the wealthy and town-dwelling classes of late medieval England are, analysis of these documents is treacherous. Just as the scribes who registered them certainly standardised the presentation of different testators' wishes, so probate procedures militated against even faintly unorthodox expression. Moreover, the proportion of a testator's movable or immovable estate represented in any given will is impossible to gauge, as a result of which no measure may be taken of any testator's devotion by comparison of his religious bequests with those made for other purposes. It must also be remembered that wills reveal nothing of the pious provision that testators undoubtedly made during their lifetimes for their own benefit. Neither do they convey any impression of what family or friends may have agreed to discharge for the benefit of a testator's soul. Late medieval wills are undeniably disappointing and frequently misleading.
Abominable Idols: Images and Image-breaking under Henry VIII
Authors: Whiting Robert
Published: March 2011

Although the Reformation under Henry viii has received relatively extensive examination from recent historians, one of its most crucial elements has continued to evade adequate investigation. Yet its impact upon the average man or woman may have been as revolutionary as the legitimisation of the English bible or the dissolution of the monasteries, and was arguably far more disruptive than governmental propaganda, ecclesiastical reformulations of dogma, or even the transfer of the supremacy from pope to king. This remarkably neglected phenomenon is the Henrician assault upon images.
Hampton Court Re-visited James I and the Puritans
Authors: Shriver Frederick
Published: March 2011

The conference between James i, some of the bishops and representatives of the puritans at Hampton Court palace in January 1604 was one of the most significant events in the political and religious history of England. But at the present time its significance is not clearly understood. The king's puritan policy did not begin or end there, but even in 1604 the conference was understood as a chance for the puritans to gain a measure of toleration or to begin a further reformation of the Church of England. As things turned out neither was the case. The classic accounts of Gardiner and Usher assumed that the conference was a failure for the puritan cause, but in 1961 Mark Curtis, in a widely accepted article, claimed that the king was more sympathetic to the puritans than Gardiner and Usher had allowed. Professor Curtis analysed the creation of the proclamation of October 1603 which announced the conference and claimed that its genesis showed a measure of serious criticism of the Established Church which has never been acknowledged by historians. He pointed out the episcopal bias of the official account of the conference, William Barlow's The Summe and Substance of the Conference… at Hampton Court, and noted the importance of what he felt was a neglected source, an ‘Anonymous Account’, which he believed showed marked differences between the king and the bishops, and emphasised the common ground between the king and the puritans. By considering the decisions made at the conference - whether they were put into effect or not - Professor Curtis was convinced that the conference itself was a puritan success in which the king made important concessions to them.