bluuebunny/crossref_metadata_2025 huggingface dataset:
Simultaneous determination of rosiglitazone and its metabolites in rat liver microsomal fraction using hollow‐fiber liquid‐phase microextraction for sample preparation
Authors: Calixto Leandro Augusto , Bonato Pierina Sueli
Published: August 2010

A three‐phase hollow‐fiber liquid‐phase microextraction method for the analysis of rosiglitazone and its metabolitesN‐desmethyl rosiglitazone and ρ‐hydroxy rosiglitazone in microsomal preparations is described for the first time. The drug and metabolites HPLC determination was carried out using an X‐Terra RP‐18 column, at 22°C. The mobile phase was composed of water, acetonitrile and acetic acid (85:15:0.5, v/v/v) and the detection was performed at 245 nm. The hollow‐fiber liquid‐phase microextraction procedure was optimized using multifactorial experiments and the following optimal condition was established: sample agitation at 1750 rpm, extraction for 30 min, hydrochloric acid 0.01 mol/L as acceptor phase, 1‐octanol as organic phase, and donor phase pH adjustment to 8.0. The recovery rates, obtained by using 1 mL of microsomal preparation, were 47–70%. The method presented LOQs of 50 ng/mL and it was linear over the concentration range of 50–6000 ng/mL, with correlation coefficients (r) higher than 0.9960, for all analytes. The validated method was employed to study thein vitrobiotransformation of rosiglitazone using rat liver microsomal fraction.
Effects of rare earth cerium addition on the synthesis and corrosion resistance of electroless Ni–PTFE–P coating
Authors: Liu D. , Zhou L. , Yu J. , Yan Y. , Lee K.
Published: August 2010

Electroless Ni–PTFE–P coatings have been successfully deposited on the surface of mild steel shaft from plating baths containing various concentrations of rare earth metal cerium (RE Ce). Surface morphology, Ce fraction, and thickness of the coatings were characterized by scanning electron microscope, inductively coupled plasma optical emission spectrometry, and reflection optical microscope, respectively. Salt spray test was used to determine the corrosion resistance of the coating. Results revealed that structure, compactness, and deposition rate of the Ni–PTFE–P coatings were increased significantly by addition of a small amount of RE Ce (10–20 ppm) to the plating bath. Electroless Ni–PTFE–P coating deposited from plating baths with 20 ppm Ce shows the highest corrosion resistance, owing to its high compactness and thickness. Deposition rate and corrosion resistance of the Ni–PTFE–P coating were deteriorated greatly as concentration of RE Ce in the plating baths exceeds 100 ppm.
Influence of corrosion on the interface between zinc phosphate steel fiber and cement
Authors: Sun M. , Wen D.‐J. , Wang H.‐W.
Published: August 2010

The interface bond between steel fibers and concrete matrix is a key factor influencing bearing capacity of steel fiber reinforced concrete (SFRC). In order to improve the interface bond strength and corrosion resistance, a kind of method was put forward by depositing zinc phosphate (ZnPh) coating on steel fiber surface in this paper. The corrosion behavior was investigated in 5% NaCl solution by using linear polarization measurement. Microstructure analysis (SEM and EDX) and fiber pull‐out test in combination with linear polarization measurement were carried out. The results prove that ZnPh coatings fabricated on the carbon steel surface can not only protect steel fiber against corrosion, but also enhance the mechanical interlocking bonds between fibers and matrix.
Corrosion of carbon steel feeders during dilute chemical decontamination of primary heat transport system of PHWRs
Authors: Subramanian H. , Madasamy P. , Sathyaseelan V. S. , Krishnamohan T. V. , Velmurugan S. , Narasimhan S. V.
Published: August 2010

Carbon steel feeders in the primary heat transport system of pressurized heavy water reactors (PHWRs) show significant wall thinning due to flow accelerated corrosion (FAC). This is of great concern, as the wear rate in certain locations exceeds the corrosion allowance by design. This necessitates periodic measurement of wall thickness and in some cases even mid course enmasse replacement of feeders. While analyzing the data on wall thicknesses and in arriving at the wall thinning rate during operation of the reactor, sufficient care has to be taken to account for the wall thinning occurring during full system chemical decontamination campaign which is carried out occasionally to reduce dose rates during reactor shut down. Chemical decontamination of primary heat transport system is carried out using a mixture of organic acids at a total concentration of about 0.1 g/L and at 85 °C. The results of experiments carried out under simulated conditions for estimating the wall thinning occurring in carbon steel feeder elbow during dilute chemical decontamination are described in this work. The corrosion rates are quantified.
Metallurgical aspects of corrosion resistance of aluminium alloys
Authors: Reboul M. C. , Baroux B.
Published: August 2010

Aluminium is the second most often used metal after steel. In this paper, the most current uses of aluminium alloys are first summarised. Then, their different corrosion modes, i.e. pitting, crevice, filiform, galvanic and structural corrosion (including inter‐granular, exfoliation and stress corrosion cracking) are reviewed, with particular attention paid to metallurgical factors controlling the corrosion process. For each mode, some instances of possible in‐service failure are given, followed by the discussion of the involved mechanisms and the presentation of appropriate solutions to prevent corrosion. Last, passivity and polarisation behaviour are discussed with reference to stainless steels.
The co‐operative effect of chloride ions and some natural extracts in retarding corrosion of steel in neutral media
Authors: Abdel‐Gaber A. M. , Abdel‐Nabey B. A. , Saadawy M.
Published: August 2010

Effect of lupine and damsissa extracts on the corrosion of steel in 0.5 M Na2SO4 solution free from and containing 0.01 or 0.1 M NaCl were examined by potentiodynamic and electrochemical impedance spectroscopy techniques. Potentiodynamic polarization curves measurements indicated that damsissa and lupine extracts behave as anodic type inhibitors. Nyquist impedance plots showed type of distorted semicircle whose size increases with increasing concentrations of lupine or damsissa extract. Increasing chloride ion concentration in the solution led to increase of the inhibition efficiency of the extract and this behaviour was explained on the basis of co‐operative mechanism of adsorption. Kinetic–thermodynamic model was used to clarify the nature of adsorption and showed good fit to the experimental data. The results indicated that lupine extract is more effective as corrosion inhibitor for steel in neutral media containing chloride ions than damsissa extract.
Damage of stainless steel bars due to atmospheric corrosion
Authors: Burkert A. , Lehmann J. , Burkert A. , Mietz J.
Published: August 2010

In addition to constructional requirements in civil engineering stainless steels often have to fulfil high visual demands. Unexpected impairments of the visual appearance of stainless steels under low corrosive conditions are a widespread problem today. Frequently it is supposed that this is caused by changes in the alloy composition, worse environmental conditions or improper handling. Within a research project the systematic investigation of several cases of damaged stainless steel bars has shown that the reasons are based on well‐known material defects like chemical inhomogeneities (e.g. precipitations or local carburization) or geometrical defects (e.g. undercuts, rolling defects or shell formation). Thus, the failures could be clearly identified as production failures of the respective semi‐finished products.
Corrosion electrochemical behaviors of silane coating coated magnesium alloy in NaCl solution containing cerium nitrate
Authors: Luo F. , Li Q. , Zhong X. K. , Gao H. , Dai Y. , Chen F. N.
Published: August 2010

Sol–gel coatings cannot provide adequate corrosion protection for metal/alloys in the corrosive environments due to their high crack‐forming potential. This paper demonstrates the possibility to employ cerium nitrate as inhibitor to decrease the corrosion development of sol–gel‐based silane coating on the magnesium alloy in NaCl solution. Cerium nitrate was added into the NaCl solution where the silane coating coated magnesium alloy was immersed. Scanning electron microcopy (SEM) was used to examine surface morphology of the silane coating coated magnesium alloy immersed in NaCl solutions doped and undoped with cerium nitrate. The corrosion electrochemical behaviors were investigated using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) tests. The results showed that the introduction of cerium nitrate into NaCl solution could effectively inhibit the corrosion of the silane coating coated magnesium alloy. Moreover, the influence of concentration of cerium nitrate on the corrosion inhibition and the possible inhibiting mechanism were also discussed in detail.
Corrosion resistance of the new Ti‐25Ta‐25Nb alloy in severe functional conditions
Authors: Vasilescu E. , Drob P. , Vasilescu C. , Drob S. I. , Bertrand E. , Gordin D. M. , Gloriant T.
Published: August 2010

In this study, a new Ti‐25Ta‐25Nb (mass%) β alloy was synthesised by cold crucible semi‐levitation melting. After melting, each ingot was solution treated in the β‐phase domain and water quenched in order to obtain a fully recrystallised homogeneous β‐phase microstructure. To evaluate the bio‐corrosion property of this new alloy, corrosion tests (cyclic potentiodynamic and linear polarisation, EIS) and surface analysis (SEM) were carried out in Ringer solution at different pH values (acid, neutral and basic). The results indicated that the corrosion resistance of the Ti‐25Ta‐25Nb alloy is quite higher than that of the commercially pure CP Ti alloy. These results show that this new alloy possesses all the characteristics necessary for its long‐term use as medical implants.
Mikto‐Arm Star Copolymers with Hyperbranched Core Structure: Synthesis by Combination of Living Radical and Condensation Polymerization
Authors: Ishizu Koji , Furuta Yuya , Okamoto Nobuyuki , Uchida Satoshi , Ozawa Masaaki
Published: August 2010

Living free‐radical copolymerization of the inimer 4‐vinylbenzyl N,N‐diethyldithiocarbamate with maleic anhydride in the presence of methyl methacrylate produces highly branched poly(methyl methacrylate) star polymers. Subsequently, mikto‐arm stars can be synthesized by condensation of poly(ethylene glycol methyl ether) monosodium alkoxide with functional maleic anhydride sites in the hyperbranched core. The solution properties of these mikto‐arm star copolymers are discussed.

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Synthesis and Properties of Alternating Fluorene‐Based Oligomers for Sub‐µm Photopatterning
Authors: Scheler Esther , Betthausen Eva , Strohriegl Peter
Published: August 2010

The synthesis of alternating photo‐crosslinkable fluorene co‐oligomers via Suzuki cross coupling is reported. The co‐oligomers were characterized using NMR and GPC, the results showing effective control of molecular weight. The oligomers have low Tgs of 53–63 °C and are thermally stable up to ≈300 °C. Using TPD as co‐monomer, a blue‐emitting oligomer was obtained, a yellow‐fluorescent material for benzothiadiazole, and a red (film) and yellow‐green (solution) emitting material for bithiophene. The energy levels are very similar to those of randomly linked oligomers. The photo‐crosslinking behavior was studied and under optimized conditions a lateral resolution of 600 nm was obtained.

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“Click” Synthesis of a Bipolar Dendrimer as a Host Material for Electrophosphorescent Devices
Authors: Yang Jun , Ye Tengling , Zhang Qing , Ma Dongge
Published: August 2010

A new solution‐processable bipolar dendrimer with carbazole units as hole‐transporting units and oxadiazole units as electron‐transporting units was efficiently synthesized based on a convergent approach by alternation of a Cu‐catalyzed azide/alkyne cycloaddition reaction and Williamson ether synthesis. The orthogonal chemistry completely avoided protection and activation of the focal points in the process of dendrimer synthesis. The dendrimer showed a wide bandgap and good thermal stability. Electrophosphorescent devices with the configuration ITO/PEDOT:PSS/bipolar dendrimer:Ir(ppy)3/TPBI/LiF/Al were fabricated. The devices showed a maximum current efficiency of 16.8 cd · A−1, a maximum power efficiency of 4.22 lm · W−1 and an external quantum efficiency of 5.7%.

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Syntheses of New 3,6‐Carbazole‐Based Donor/Acceptor Conjugated Copolymers for Optoelectronic Device Applications
Authors: Lai Mei‐Hsiu , Tsai Jung‐Hsun , Chueh Chu‐Chen , Wang Chih‐Feng , Chen Wen‐Chang
Published: August 2010

The syntheses, properties, and optoelectronic device characteristics of four new 3,6‐carbazole‐based donor/acceptor conjugated copolymers are reported. Such copolymers are used to explore the effects of acceptor strength and backbone coplanarity on the electronic and optoelectronic properties. The optical bandgaps of the studied copolymers are PCzQ (2.29 eV) > PCzDTQ (1.91 eV) > PCzTP (1.75 eV) > PCzDTTP (1.49 eV), which are much smaller than the parent poly(3,6‐carbazole). The power conversion efficiency of the photovoltaic cells fabricated from blends of copolymer/PC61BM or PC71BM reached 1.01 and 1.73% by varying the film thickness or blend ratio. The experimental results suggest the potential application of 3,6‐carbazole acceptor conjugated copolymers in optoelectronic devices.

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Conductive UV‐Cured Acrylic Inks for Resistor Fabrication: Models for their Electrical Properties
Authors: Chiolerio A. , Vescovo L. , Sangermano M.
Published: August 2010

We report the preparation of acrylic inks for specific electrical applications, such as resistors, based on a UV‐cured resin (PEGDA), where an in situ synthesis of silver nanoparticles is performed. The conversion, gel content and morphology of the nanoparticles, with a specific interest about the size distribution and electrical conductivity at room temperature, are considered. Aging and electromigration are evaluated to confirm the stability of the samples. A correlation between the morphological properties and the electrical ones is given, in particular developing the universal percolation theory and an extension of the Vegard law for composites. Interesting conclusions are drawn based on the application of the models.

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Novel Foams Based on Freeze‐Dried Renewable Vital Wheat Gluten
Authors: Blomfeldt Thomas O.J. , Olsson Richard T. , Menon Mohan , Plackett David , Johansson Eva , Hedenqvist Mikael S.
Published: August 2010

A new way of producing rigid or semi‐rigid foams from vital wheat gluten using a freeze‐drying process is reported. Water/gluten‐based mixtures were frozen and freeze‐dried. Different foam structures were obtained by varying the mixing process and wheat gluten concentration, or by adding glycerol or bacterial cellulose nanofibers. MIP revealed that the foams had mainly an open porosity peaking at 93%. The average pore diameter ranged between 20 and 73 µm; the sample with the highest wheat gluten concentration and no plasticizer had the smallest pores. Immersion tests with limonene revealed that the foams rapidly soaked up the liquid. An especially interesting feature of the low‐wheat‐concentration foams was the “in situ” created soft‐top‐rigid‐bottom foams.

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Micropatterning of Electrospun Polyurethane Fibers Through Control of Surface Topography
Authors: Dempsey David K. , Schwartz Christian J. , Ward Robert S. , Iyer Ananth V. , Parakka James P. , Cosgriff‐Hernandez Elizabeth M.
Published: August 2010

A novel technique was developed to control the deposition of electrospun polyurethane fibers using a silicone collector substrate patterned with soft lithography. This method can be used to control selective fiber deposition with broad pattern dimensions (50–500 µm) over a large area. The combination of ease of use, low cost, tunability, and generation of relatively large fiber mats available with this technique is expected to advance our ability to mimic the orientation and anisotropic properties of native tissues to generate improved tissue engineering scaffolds.

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Morphology and Thermal Stability of Novolac Phenolic Resin/Clay Nanocomposites Prepared via Solution High‐Shear Mixing
Authors: Zhang Zhihao , Ye Guozhong , Toghiani Hossein , Pittman Charles U.
Published: August 2010

Phenolic resin/clay composites were prepared by high‐shear mixing of clay suspended in CH3OH solutions of Novolac resin and curing agent. Pure clay Cloisite Na+ and pillared clays Cloisite 10A, 30B, and Na+Cloisite that was pillared by 3‐hexadecyl‐1‐methylimidazolium bromide were studied. After CH3OH evaporation, Novolac was cured at low temperatures. XRD showed that clay gallery d‐spacings decreased upon solvent evaporation and partial curing. Slight d‐spacing increases were sometimes observed from a partially cured stage to a further cured composite. Na+Cloisite gave the highest nanodispersion, Cloisites 10A and 30B the lowest. TGA revealed that Na+ clay or organoclay incorporation in partially cured and cured composites did not improve the thermal stability of Novolac.

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High Solids Content, Soap‐Free, Film‐Forming Latexes Stabilized by Laponite Clay Platelets
Authors: Bourgeat‐Lami Elodie , Guimarães Thiago Rodrigues , Pereira Ana Maria Cenacchi , Alves Gizelda Maria , Moreira José Carlos , Putaux Jean‐Luc , dos Santos Amilton Martins
Published: August 2010

High solids content film‐forming poly[styrene‐co‐(n‐butyl acrylate)] [poly(Sty‐co‐BuA)] latexes armored with Laponite clay platelets have been synthesized by soap‐free emulsion copolymerization of styrene and n‐butyl acrylate. The polymerizations were performed in batch in the presence of Laponite and a methyl ether acrylate‐terminated poly(ethylene glycol) macromonomer in order to promote polymer/clay association. The overall polymerization kinetics showed a pronounced effect of clay on nucleation and stabilization of the latex particles. Cryo‐transmission electron microscopy observation confirmed the armored morphology and indicated that the majority of Laponite platelets were located at the particle surface. The resulting nanostructured films displayed enhanced mechanical properties.

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Thermoprecipitation of Glutathione S‐Transferase by Glutathione–Poly(N‐isopropylacrylamide) Prepared by RAFT Polymerization
Authors: Chang Chien‐Wen , Nguyen Thi H. , Maynard Heather D.
Published: August 2010

Herein, we report an effective and rapid method to purify glutathione S‐transferase (GST) using glutathione (GSH)‐modified poly(N‐isopropylacrylamide) (pNIPAAm) and mild, thermal conditions. A chain transfer agent modified with pyridyl disulfide was employed in the reversible addition–fragmentation chain transfer (RAFT) polymerization of NIPAAm. The resulting polymer had a narrow molecular weight distribution (polydispersity index = 1.21). Conjugation of GSH to the pyridyl disulfide–pNIPAAm reached 95% within 30 min as determined by UV–Vis monitoring of the release of pyridine‐2‐thione. GST was successfully thermoprecipitated upon heating the GSH–pNIPAAm above the lower critical solution temperature (LCST). The pull down assay was repeated with bovine serum albumin (BSA) and T4 lysozyme (T4L), which demonstrated the specificity of the polymer for GST. Due to its simplicity and high efficiency, this method holds great potential for large‐scale purification of GST‐tagged proteins.

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Glycolaldehyde‐modified β‐lactoglobulin AGEs are unable to stimulate inflammatory signaling pathways in RAGE‐expressing human cell lines
Authors: Buetler Timo M. , Latado Hélia , Leclerc Estelle , Weigle Bernd , Baumeyer Alexandra , Heizmann Claus W. , Scholz Gabriele
Published: August 2010

Scope: Advanced glycation endproducts (AGEs) are suspected to stimulate inflammatory signaling pathways in target tissues via activation of the receptor for AGEs. Endotoxins are generally recognized as potential contamination of AGE preparations and stimulate biological actions that are very similar as or identical to those induced by AGEs.

Methods and results: In our study, we used glycolaldehyde‐modified β‐lactoglobulin preparations as model AGEs and employed two methods to remove endotoxin using either affinity columns or extraction with Triton X‐114 (TX‐114). Affinity column‐purified AGEs retained their ability to stimulate inflammatory signaling as measured by mRNA expression of inflammatory cytokines in the human lung epithelial cell line Beas2b. However, glycolaldehyde‐modified AGEs purified by extraction with TX‐114 did not show any stimulation of mRNA expression of inflammatory cytokines. The presence of a cell stimulating endotoxin‐like activity was demonstrated in the detergent phase after extraction with TX‐114, thus indicating that not AGEs but a lipophilic contamination was responsible for the stimulation of inflammatory signaling.

Conclusion: Our results demonstrate that glycolaldehyde‐modified AGEs are unable to induce inflammatory signaling in receptor for AGE‐expressing cells. The observed cell‐activating activity can be ascribed to an endotoxin‐like lipophilic contamination present in AGE preparations and affinity column purification was insufficient to remove this contamination.
Temporal resolution and SNR requirements for accurate DCE‐MRI data analysis using the AATH model
Authors: Kershaw Lucy E. , Cheng Hai‐Ling Margaret
Published: August 2010

Dynamic contrast‐enhanced MRI has been used in conjunction with tracer kinetics modeling in a wide range of tissues for treatment monitoring, oncology drug development, and investigation of disease processes. Accurate measurement of model parameters relies on acquiring data with high temporal resolution and low noise, particularly for models with large numbers of free parameters, such as the adiabatic approximation to the tissue homogeneity model for separate measurements of blood flow and vessel permeability. In this simulation study, accuracy of the adiabatic approximation to the tissue homogeneity model was investigated, examining the effects of temporal resolution, noise levels, and error in the measured arterial input function. A temporal resolution of 1.5 s and high SNR (noise sd = 0.05) were found to ensure minimal bias (<5%) in all four model parameters (extraction fraction, blood flow, mean transit time, and extravascular extracellular volume), and the sampling interval can be relaxed to 6 s, if the transit time need not be measured accurately (bias becomes >10%). A 10% error in the measured height of the arterial input function first pass peak resulted in an error of at most 10% in each model parameter. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
Dependence of blood R2 relaxivity on CPMG echo‐spacing at 2.35 and 7 T
Authors: Gardener Alexander G. , Francis Susan T. , Prior Malcolm , Peters Andrew , Gowland Penny A.
Published: August 2010

The transverse relaxation rate (R2) of fresh human blood has been investigated at high and ultrahigh field, to characterize the R2 dependency on blood sample oxygenation, hematocrit, and Carr‐Purcell Meiboom‐Gill sequence inter‐echo spacing. Data were fitted to chemical exchange and diffusion models to assess their performance at different field strengths. The diffusion model gave a slightly superior fit at both field strengths, but the difference is unlikely to be relevant for the signal to noise ratio achieved in most in vivo experiments. Fitted model parameters were similar to those found in literature. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
Tat acetylation regulates its actions on microtubule dynamics and apoptosis in T lymphocytes
Authors: Huo Lihong , Li Dengwen , Sun Lei , Liu Min , Shi Xingjuan , Sun Xiaoou , Li Jingyu , Dong Bin , Dong Xin , Zhou Jun
Published: August 2010

The transactivator protein Tat of human immunodeficiency virus type 1 (HIV‐1) is known to suppress microtubule dynamics and thereby trigger apoptosis in T lymphocytes. These actions of Tat constitute one of the major mechanisms for the massive destruction of T lymphocytes associated with the acquired immunodeficiency syndrome. Herein, we show that Tat acetylation at lysine‐28 (K28) enhances its interaction with microtubules and increases its activity to promote microtubule assembly, by lowering the critical concentration of tubulin for polymerization into microtubules. In addition, K28 acetylation enhances the ability of Tat to stabilize microtubules, leading to increased apoptosis in T lymphocytes. Our data further reveal that Tat acetylation at K28 stimulates its activity to induce the translocation of Bim, a pro‐apoptotic protein of the Bcl‐2 family, from microtubules to mitochondria. These findings provide the first evidence that Tat acetylation regulates its actions on microtubule dynamics and apoptosis, in addition to the regulation of its transactivation activity. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
HCMV seroprevalence and associated risk factors in pregnant women, Havana City, 2007 to 2008
Authors: Correa C. B. , Kourí V. , Verdasquera D. , Martínez P. A. , Alvarez A. , Alemán Y. , Pérez L. , Viera J. , González R. , Pérez E. , Moro I. , Navarro M. A. , Melin P.
Published: August 2010

Objective

To prenatally identify pregnant women at risk of developing congenital infection due to human cytomegalovirus (HCMV).

Methods

One thousand one hundred and thirty‐one pregnant women from three municipalities from Havana City were serologically screened for HCMV infection (IgM/IgG, IgG avidity) from January 2007 to January 2008. Demographical, epidemiological, and clinical variables were correlated to serologic status to identify predictors of seroconversion in pregnancy.

Results

The majority of women were seropositive to HCMV (92.6%); 27 women (2.4%) developed HCMV active infection during pregnancy, defined by the detection of IgG+ and IgM+ (7 women), IgM+ and IgG− (2 women), and IgG seroconversion (18 women). Susceptibility of active HCMV infection during pregnancy was associated with maternal age < 20 years and nulligravidity. Primary infection was detected in 20 pregnant women (1.8%), whereas 7 patients (0.6%) had active non‐primary infection.

Conclusion

Although pregnant women in Cuba have high seroprevalence rates for HCMV, those younger than 20 years and nulligravidae are at risk of acquiring infection during pregnancy. Copyright © 2010 John Wiley & Sons, Ltd.
Type 1, tents, take‐aways and toilets: how to manage at a music festival
Authors: Charlton J , Mackay L
Published: August 2010

Maintaining optimal glycaemic control in people with type 1 diabetes is challenging. Attending a weekend music festival encompasses lifestyle activities that increase the challenge. These include: increased exercise, and changes in eating and alcohol consumption. The practicalities of blood glucose monitoring and insulin injections are also a consideration.

The aim of this project was to identify realistic problems for people with type 1 diabetes attending a music festival, and to review current written advice and available literature in order to provide relevant information.

No literature was identified. Fifty people with type 1 diabetes aged 18–40 years were randomly selected and sent a questionnaire enquiring about experiences.

Thirteen responded (26%). The mean duration of diabetes was 11.7 years (range 1.5–28 years). All 13 respondents had attended a music festival; of these, 46% had attended one for the first time. Some of the concerns included: hypoglycaemia (31%), lack of food (23%), losing insulin and equipment (23%), and maintaining blood glucose levels (23%). Anxieties regarding hypoglycaemia resulted in 38% running blood glucose levels higher than normal. Thirty‐eight percent experienced hypoglycaemia, the reasons being: increased activity (38%), eating less carbohydrate (8%), and reduced blood glucose testing (8%). Twenty‐three percent attended the first aid tent: 15% regarding injections and 8% for non‐diabetic reasons.

An information leaflet regarding managing diabetes when attending a festival has been designed which includes feedback and tips from patients. The leaflet was evaluated by 50 people with type 1 diabetes, and 20 health care professionals.

Currently, negotiations are underway with Diabetes UK, T in the Park festival organisers and the St Andrew's Ambulance Service to have an advice stand at the festival. Copyright © 2010 John Wiley & Sons.
Efficacy of a staged diabetes management programme in achieving glycaemic goal in a low socio‐economic Hispanic population
Authors: Beale EO , Lee WA , Chan LS
Published: August 2010

The aim of this study was to identify the efficacy of a staged diabetes management (SDM) clinic serving a low socio‐economic Hispanic population in achieving glycaemic goal.

We analysed prospectively collected data from patients discharged from the clinic in 2008 with an admission HbA1c >8% (64mmol/mol) and >one clinic visit. Adjusted odds ratios (AOR) were determined for factors significantly associated with glycaemic goal achievement.

Both those patients who achieved the clinic HbA1c goal of ≤8% (n=277) and those who did not (n=209) had a clinically significant decrease in HbA1c (‐3.13±1.80, ‐1.08±1.78). After adjustment, the following were associated with failure to achieve goal: higher admission HbA1c (%) 11.0±1.8 vs 10.3±1.7, AOR (95% CI) 1.22 (1.08, 1.37), p=0.0016; higher admission insulin (IU/kg/day) 0.56±0.58 vs 0.26±0.41, AOR 2.08 (1.09, 4.00), p=0.026; greater increase in insulin (IU/kg/day) 0.23±0.46 vs 0.09±0.32, AOR 2.38 (1.15, 5.00), p=0.02; and a longer stay (days) 229±110 vs 172±84, AOR 1.007 (1.003, 1.012), p=0.0008.

In this SDM clinic, most patients achieved significant reduction in HbA1c. The study identified factors associated with a lower likelihood of achieving goal thereby demonstrating the value of review of the response to an SDM protocol in indicating areas for further improvement. Copyright © 2010 John Wiley & Sons.
Polymerization of ε‐caprolactone on calcium alkoxide‐functionalized silica substrates
Authors: Khan Javaid H , Schue Francois , George Graeme A
Published: August 2010

Biodegradable composite materials free from toxic initiator residues have been prepared using calcium alkoxides bound to silica. Polycaprolactone with low polydispersity was synthesized by ring‐opening polymerization of ε‐caprolactone at 100 °C on a calcium alkoxide‐functionalized silica substrate prepared by the grafting of a hydrolysed epoxy silane onto silica gel, followed by reaction with calcium hydride. The polymerization was also initiated by the product of the direct reaction of calcium hydride with unfunctionalized silanol groups. Characterization of the reaction products and the real‐time reaction kinetics using Raman spectroscopy suggests a living coordination–insertion mechanism. There is a difference in reactivity of a factor ofca7 between the calcium alkoxide formed on the silanized and unsilanized silica surface, resulting in a monomer conversion of 90% in 100 h for the silanized silica compared to only 30% for the unsilanized silica. The degree of grafting ranges from a maximum of 30% for the silanized surface to 10% for the unsilanized silica alone. There is evidence for cyclic transesterification products, and release of the polymer from the silica occurs in this way and also by adventitious hydrolysis. Copyright © 2010 Society of Chemical Industry
A copolymer of poly[2,2′‐(m‐phenylene)‐5,5′‐ bibenzimidazole] and poly(2,5‐benzimidazole) for high‐temperature proton‐conducting membranes
Authors: Yang Jingshuai , He Ronghuan , Che Quantong , Gao Xiaolei , Shi Lili
Published: August 2010

A novel copolymer of polybenzimidazoles was prepared by copolymerization of 3,3′‐diaminobenzidine tetrahydrochloride, 3,4‐diaminobenzoic acid and isophthalic acid in polyphosphoric acid at 200 °C. The polymerization could be performed within 90–110 min with the assistance of microwave irradiation. The solubility of the copolymer obtained in N,N‐dimethylacetamide (DMAc) was improved compared with those of poly[2,2′‐(m‐phenylene)‐5,5′‐bibenzimidazole] and poly(2,5‐benzimidazole). Thus copolymer membranes could be readily prepared by dissolving the copolymer powders in DMAc with refluxing under ambient pressure. The decomposition temperature of the copolymer was about 520 °C in air according to thermogravimetric analysis data. The proton conductivity and mechanical strength of the phosphoric acid‐doped copolymer membranes were investigated at elevated temperatures. A conductivity of 0.09 S cm−1 at 180 °C and a tensile stress at break of 5.9 MPa at 120 °C were achieved for the acid‐doped copolymer membranes by doping acids in a 75 wt% H3PO4 solution. Copyright © 2010 Society of Chemical Industry
ABTS•+ scavenging activity of polypyrrole, polyaniline and poly(3,4‐ethylenedioxythiophene)
Authors: Hsu Chyong Fang , Peng Hui , Basle Cédric , Travas‐Sejdic Jadranka , Kilmartin Paul A
Published: August 2010

Although many methods are available for the evaluation of the antioxidant capacity of samples presented in the liquid state, typically food and beverages, to date only the 2,2′‐diphenyl‐1‐picrylhydrazyl (DPPH) assay has been applied to the measurement of the antioxidant capacity of solid samples such as active packaging materials. A modified 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) diammonium salt (ABTS) assay has been successfully developed for the measurement of the antioxidant capacity of conducting polymer powders. The ABTS•+ radical scavenging activity of polypyrrole (PPy), polyaniline (PANI) and poly(3,4‐ethylenedioxythiophene) (PEDOT) powders was compared. The ranking order for greatest antioxidant capacity among the conducing polymer powders was PANI > PPy > PEDOT. The reduced forms of all the three conducting polymer samples were found to show greater radical scavenging activity than their as‐prepared partially oxidized forms. The modified ABTS assay is a simple, rapid and sensitive method for evaluating the antioxidant capacity of conducting polymer powders. The method is also suitable for composite antioxidant materials comprising a conducting polymer and a conventional packaging polymer. Copyright © 2010 Society of Chemical Industry
Molten‐salt synthesis of oxyapatite La9.33Si6O26powders as electrolytes for intermediate temperature solid oxide fuel cells
Authors: Huang Zhaoxiang , Li Buyin , Liu Jia
Published: August 2010

Lanthanum silicate oxy‐apatites are thought of as ytrria‐stabilized zirconia substitutes in intermediate temperature solid oxide fuel cells. Lanthanum silicate oxy‐apatite powders La9.33Si6O26are successfully synthesized at lower temperature by a molten‐salt method. X‐ray diffraction, scanning electron microscopy, and precision impedance analysis used to characterize the structure, appearance, and conductivity of La9.33Si6O26. The results indicate that the apatite phase has been synthesized. The synthesis method decreases the synthesis temperature by about 300 °C in comparison to the conventional solid‐state reaction route and obtains homogeneous and nanosize powders. Dense ceramics have been prepared at sintering temperatures around 1450 °C. The used of molten‐salt powders allows a decrease of the dense ceramic pellet sintering temperature of about 200 °C. The ceramic pellets sintering at 1550 °C for 4 h have a relative density of 92% and an electrical conductivity of 1.1 × 10−3 S cm−1at 700 °C, higher than the some reported for the solid‐state synthesis method and the sol–gel method.
Adsorption of cytochrome c on diamond
Authors: Hoffmann René , Kriele Armin , Kopta Susanne , Smirnov Waldemar , Yang Nianjun , Nebel Christoph E.
Published: August 2010

The adsorption and conformational state of the electron transfer protein cytochrome c (cyt c) on flat, boron doped polycrystalline diamond electrodes was investigated using electrochemical techniques and atomic force microscopy (AFM). An electrochemical reduction wave from the adsorbed protein was identified as oxygen reduction, which is catalysed by the deformed heme redox centre of cyt c. We show that this catalytic activity only occurs after partial denaturation of cyt c. Therefore the reduction peak was used for characterization of the conformational state of adsorbed cyt c. AFM characterizations with molecular resolution show different conformational states of cyt c on diamond surfaces ranging from native to denaturated. Both applied techniques indicate that hydrophobic hydrogenated diamond tends to denaturate cyt c upon adsorption, while wet chemically oxidized diamond surfaces can provide extensive but non‐denaturating cyt c adsorption. The conformation and orientation of cyt c on wet chemically oxidized diamond is beneficial for the electron transfer between the protein redox centre and the diamond electrode even in the presence of oxygen.
High breakdown voltage Schottky diodes synthesized on p‐type CVD diamond layer
Authors: Volpe Pierre‐Nicolas , Muret Pierre , Pernot Julien , Omnès Franck , Teraji Tokuyuki , Jomard François , Planson D. , Brosselard Pierre , Dheilly Nicolas , Vergne Bertrand , Scharnholtz Sigo
Published: August 2010

Diamond is a very promising material for power electronics and electrical energy management devices. Several architectures have been implemented in the past for the fabrication of Schottky diodes on boron doped microwave plasma enhanced chemical vapour deposition (MPCVD) layers and on lowly and highly boron doped stacked structures. Meanwhile, the performances often suffered several limitations, mainly due to insufficient crystalline quality of the layers or a non‐optimized diamond/metal interface. In this study, we will especially show that the achievement of diamond Schottky diode with high breakdown reverse voltage and high breakdown field goes through the optimization of several factors: a net acceptor concentration below 1016 cm−3, the epilayer growth conditions, the implementation of efficient surface passivation techniques and the integrity of the metal/diamond interface. Optimizing the previous conditions enabled us to fabricate a lateral gold Schottky diodes withdrawing reverse voltages up to 7.5 kV before avalanche breakdown induced by an electric field in the range 7–9.5 MV/cm. These findings open the route for unipolar diamond devices operating in high power electronics without the use of guard rings or edge terminations contrary to other wide band gap semiconductors.
Boron doped nanocrystalline diamond temperature regulator for sensing applications
Authors: Clukers Tim , Grinsven Bart Van , Vandenryt Thijs , Janssens Stoffel D. , Wagner Patrick , De Ceuninck Ward , Thoelen Ronald , Daenen Michaël , Haenen Ken
Published: August 2010

In search for a better way to monitor the hybridization and denaturation of DNA onto a diamond based sensor, precise knowledge about the conditions of the immediate surroundings is very critical. One of the factors that have a great influence on the stability of the measurements is the temperature of the liquid environment in which these measurements take place. With this as a focal point, the design of a precise temperature regulator based on a boron doped diamond thin film is a key factor to achieve accurate measurements on a standalone basis. In this work temperature control is achieved making use of a thin boron doped nanocrystalline diamond (B‐NCD) film, which, in combination with a proportional‐integral‐derivative‐control (PID), is able to maintain a stable temperature with an accuracy better than 0.1 °C. By letting the B‐NCD‐layer act as a resistor together with the appropriate control it is possible to maintain a stable temperature in a range going from room temperature till 70 °C, with an accuracy exceeding a temperature variation 0.1 °C. The first prototype makes use of a reference temperature sensor, to verify the accuracy of the results.
Accuracy of quantum Monte Carlo methods for point defects in solids
Authors: Parker William D. , Wilkins John W. , Hennig Richard G.
Published: August 2010

Quantum Monte Carlo (QMC) approaches such as the diffusion Monte Carlo (DMC) method are among the most accurate many‐body methods for extended systems. Their scaling makes them well suited for defect calculations in solids. We review the various approximations needed for DMC calculations of solids and the results of previous DMC calculations for point defects in solids. Finally, we present estimates of how approximations affect the accuracy of calculations for self‐interstitial formation energies in silicon and predict DMC values of 4.4(1), 5.1(1), and 4.7(1) eV for the X, T, and H interstitial defects, respectively, in a 16(+1)‐atom supercell.
Template‐directed synthesis of hybrid nanowires and nanorods
Authors: Yuan Jiayin , Walther Andreas , Müller Axel H. E.
Published: August 2010

Recently, one‐dimensional (1D) nanostructures, such as wires, rods, tubes, etc., have attracted considerable attention due to their unique shape‐ and size‐dependant properties and many potential applications. Template‐directed synthesis is a powerful and widely used method to prepare 1D objects. As robust unimolecular template, cylindrical polymer brushes have been exploited for the fabrication of various hybrid nanowires and nanorods, for instance, γ‐Fe2O3, CdS, CdSe, TiO2, silica, Au, Te, etc. As a key advantage of this polymeric templating, the obtained 1D hybrid nanostructures are colloidally stable in solution, facilitating their further solution processing.

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Cryo‐TEM image of organo‐silica hybrid nanowires in aqueous solution (the inset shows a cartoon of the structure).
Surface effects and nonlinear optical properties of ZnO nanowires
Authors: Voss Tobias , Richters Jan‐Peter , Dev Apurba
Published: August 2010

This paper discusses the surface effects and nonlinear optical properties of ZnO nanowires. First, the influence of the large surface‐to‐volume ratio of the nanowires on their photoluminescence properties is shown. The occurrence of a surface‐exciton emission line is demonstrated and its properties are studied in time‐integrated and time‐resolved photoluminescence measurements. It is further demonstrated that this band is sensitive to surface modifications of the nanowires, such as dielectric and metallic coatings. It is shown that hydrogen can passivate deep defects in ZnO nanowires thereby reducing the defect luminescence and strongly enhancing the near‐band‐edge excitonic luminescence. The photoluminescence properties of chemically synthesized ZnO nanowires are compared to those of nanowires grown by vapor‐transport techniques. The non‐linear coefficients of chemically synthesized nanowires are analyzed, and first preliminary measurements of the optical gain of a ZnO nanowire waveguide are analyzed.

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Zincoxide nanowires under optical excitation.
Pros and cons of green InGaN laser on c‐plane GaN
Authors: Strauß Uwe , Avramescu Adrian , Lermer Teresa , Queren Désirée , Gomez‐Iglesias Alvaro , Eichler Christoph , Müller Jens , Brüderl Georg , Lutgen Stephan
Published: August 2010

The challenges of green InGaN lasers are discussed concerning material quality as a function of InGaN composition, quantum well design and piezoelectrical fields. Investigations of polar quantum well designs and comparison with simulated non‐polar structures demonstrate that the quality of the indium rich layers is more important than the influence of interface charges. A high risk of dark spots at high In concentrations of 26–33% is observed. Small changes of about 2% of In significant reduce or increase the quantity and size of dark luminescence areas. Polar designs are a trade‐off between low indium concentrations of 4 nm wide quantum wells and high overlap of electrons and holes in 2 nm narrow designs. Furthermore, our single quantum wells have less non‐radiative defects than indium rich multi‐quantum well structures. Optimized active layer designs and the material qualities enable us to get green InGaN lasers on c‐plane substrates for cw operation at 515–524 nm and wall plug efficiencies of 3.9–2.3%. Slope efficiency of 0.3–0.4 W/A allows up to now highest optical output power of 50 mW.
Which electronic structure method for the study of defects: A commentary
Authors: Lambrecht Walter R. L.
Published: August 2010

A historic perspective is provided to the choice of methodologies for point defects in semiconductors. A summary and commentary on the highlights of the CECAM workshop: “Which electronic structure method for the study of defects?” is given, attempting to provide a link between the different contributions. To this purpose different themes running through the compilation are identified and rather than discussing individual contributions one by one, the discussion is focused around these themes. The first theme is the problem of correcting for finite size effects. The second theme is the problem of the underestimate of the band gaps and how to correct for it in defect calculations. The third theme is the self‐interaction error of local density approximation (LDA) and its repercussions for polaronic defects. The fourth theme is progress in methods beyond LDA that are becoming applicable to point defects, either for ground states or excited state properties.
Anomalies of thermal expansion and change of entropy of rare‐earth diborides at the temperatures of magnetic transitions
Authors: Novikov Vladimir , Chukina Tatiana
Published: August 2010

An entropy method has been proposed for calculating magnetic heat capacity Cm of rare‐earth diborides on their thermal expansion data. It was found that the temperature changes of magnetic entropy ΔSm(T) calculated from calorimetric data correlate with the magnetic components of lattice parameters Δam(T) and Δcm(T) calculated from X‐ray diffraction data. Using this correlation, a formula for Cm(T) has been derived. Calculations of Cm(T) for TbB2, DyB2, HoB2, and ErB2 have been carried out. The temperature dependencies Cm(T) obtained from X‐ray diffraction data are in a good agreement with the calorimetric data.
Agarose optical fibre humidity sensor based on electromagnetic resonance in the infra‐red region
Authors: Hernaez Miguel , Zamarreño Carlos R. , Fernandez‐Valdivielso Carlos , del Villar Ignacio , Arregui Francisco J. , Matias Ignacio R.
Published: August 2010

A new optical fibre humidity sensor based on electromagnetic resonances (EMR) is presented in this work. An ITO layer deposited onto a 200 µm core fibre has been used as EMR supporting coating. The resultant device works as a refractometer whose EMR absorption peak shifts when the refractive index of the surrounding medium varies. An agarose layer, whose refractive index changes when it is subjected to relative humidity (RH) variations, has been deposited onto the ITO layer. This way, the new device shows a good sensitivity to RH variations, with a dynamical range of 45 nm between 20 and 80% RH. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Morphology controlled hydrothermal synthesis processes and emission near 2 µm of Tm3+‐doped Lu2O3nanostructures
Authors: Cascales Concepción , Esteban‐Betegón Fátima , Zaldo Carlos
Published: August 2010

Hydrothermal syntheses at 185 °C for 24 h yield pure cubic Ia $ \bar 3 $ nanocrystalline Tm3+‐doped Lu2O3 materials, whose morphologies are controlled through the conditions of the reaction. Chloride reagents under mild conditions produce rods of ∼15 µm length x 90 nm ∅︁ size. These nanorods exhibit photoluminescence at ∼1.95 µm, and fluorescence lifetime τ = 976 µs has been measured for 3F4 in the 2% mol Tm3+‐doped Lu2O3 sample (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)