bluuebunny/crossref_metadata_2025 huggingface dataset:
Organizational change in the U.S. Afghan diaspora: A response to homeland events or heightened government scrutiny?
Authors: Kerlin Janelle A. , Manikowski Susan
Published: June 2011

This article examines factors behind a post–September 11, 2001, increase in the number of U.S.‐based Afghan nonprofits registering or filing with the Internal Revenue Service (IRS) for the first time. The nonprofit literature suggests that increased government scrutiny of charitable activities has caused nonprofits to change their behavior. However, empirical evidence behind these claims is lacking. Philanthropy researchers also discuss the response of ethnic diasporas in the United States to crises and other events in their homelands, though rarely from an organizational perspective. This study examines whether heightened government scrutiny, homeland events, or some other factor was most responsible for the increase in U.S.‐based Afghan nonprofits initiating IRS contact following September 11. Survey research finds that Afghan nonprofits, though arguably greater targets for IRS scrutiny due to their Middle East connections, were more motivated by events in their homeland than by heightened government scrutiny to register and file with the IRS.
Nonprofit watchdogs: Do they serve the average donor?
Authors: Cnaan Ram A. , Jones Kathleen , Dickin Allison , Salomon Michele
Published: June 2011

Nonprofit watchdog organizations—organizations devoted to rating the accountability and transparency of nonprofits—claim to serve donors who are selecting which nonprofits to support. However, using three waves of the Harris Interactive Donor Pulse, we found that the overwhelming majority of donors (77.6 percent) do not consult these online intermediaries when making donations. Those who do are likely to fall into one of two groups: donors who give large sums of money or donors who are engaged in advocacy. We conclude with conceptual and practical implications.
Enhanced Euler's method to a free boundary porous media flow problem
Authors: Zhang Jianying , Jiang Bin
Published: June 2011

We study an ODE‐based iterative method, the residual velocity method, for steady state free boundary problems. The convergence analysis of the method, as well as the numerical implementation based on Euler's method were provided by Donaldson and Wetton (J Appl Math 71 (2006), 877–897). In this article, we develop an enhanced Euler's method which is nearly as simple as the modified Euler's method but can achieve a rapid convergence rate similar to the fourth‐order Runge‐Kutta method. Numerical results are also provided to verify the validity of our method. © 2011 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2012
Response to steroids predicts response to rituximab in pediatric chronic immune thrombocytopenia
Authors: Grace Rachael F. , Bennett Carolyn M. , Ritchey A. Kim , Jeng Michael , Thornburg Courtney D. , Lambert Michele P. , Neier Michelle , Recht Michael , Kumar Manjusha , Blanchette Victor , Klaassen Robert J. , Buchanan George R. , Kurth Margaret Heisel , Nugent Diane J. , Thompson Alexis A. , Stine Kimo , Kalish Leslie A. , Neufeld Ellis J.
Published: June 2011

Background

Treatment choice in pediatric immune thrombocytopenia (ITP) is arbitrary, because few studies are powered to identify predictors of therapy response. Increasingly, rituximab is becoming a treatment of choice in those refractory to other therapies.

Methods

The objective of this study was to evaluate univariate and multivariable predictors of platelet count response to rituximab. After local IRB approval, 565 patients with chronic ITP enrolled and met criteria for this study in the longitudinal, North American Chronic ITP Registry (NACIR) between January 2004 and October 2010. Treatment response was defined as a post‐treatment platelet count ≥50,000/µl within 16 weeks of rituximab and 14 days of steroids. Treatment response data were captured both retrospectively at enrollment and then prospectively.

Results

Eighty (14.2%) patients were treated with rituximab with an overall response rate of 63.8% (51/80). Univariate correlates of response to rituximab included the presence of secondary ITP and a positive response to steroids. In multivariable analysis, response to steroids remained a strong correlate of response to rituximab, OR 6.8 (95% CI 2.0–23.0, P = 0.002). Secondary ITP also remained a strong predictor of response to rituximab, OR 5.6 (95% CI 1.1–28.6, P = 0.04). Although 87.5% of patients who responded to steroids responded to rituximab, 48% with a negative response to steroids did respond to rituximab.

Conclusion

In the NACIR, response to steroids and presence of secondary ITP were strong correlates of response to rituximab, a finding not previously reported in children or adults. Pediatr Blood Cancer 2012; 58: 221–225. © 2011 Wiley Periodicals, Inc.
Evaluation of diagnostic performance of CT for detection of tumor thrombus in children with Wilms tumor: A report from the Children's Oncology Group
Authors: Khanna Geetika , Rosen Nancy , Anderson James R. , Ehrlich Peter F. , Dome Jeffrey S. , Gow Kenneth W. , Perlman Elizabeth , Barnhart Douglas , Karolczuk Kathryn , Grundy Paul
Published: June 2011

Background

Pre‐operative assessment of intravascular extension of Wilms tumor is essential to guide management. Our aim is to evaluate the diagnostic performance of multidetector CT in detection of tumor thrombus in Wilms tumor.

Procedure

The study population was drawn from the first 1,015 cases in the AREN03B2 study of the Children's Oncology Group. CT scans of children with (n = 62) and without (n = 111) tumor thrombus at nephrectomy were independently reviewed by two radiologists, blinded to patient information. Doppler sonography results were obtained from institutional radiology reports, as Doppler requires real‐time evaluation. The diagnostic performance of CT and Doppler for detection of tumor thrombus was determined using nephrectomy findings as reference standard.

Results

In the primary nephrectomy group, tumor thrombus detection sensitivity, specificity of CT was 65.6, 84.8%, and Doppler was 45.8, 95.7%, respectively. In this group, sensitivity of CT, Doppler for detection of cavoatrial thrombus was 84.6 and 70.0%, respectively. In the secondary nephrectomy group, tumor thrombus detection sensitivity, specificity of CT was 86.7, 90.6%, and Doppler was 66.7, 100.0%, respectively. In this group, sensitivity of CT, Doppler for detection of cavoatrial thrombus was 96.0 and 68.8%, respectively. Pre‐operative Doppler evaluation performed in 108/173 cases, detected 3 cases with intravenous extension (2 in renal vein, 1 in IVC at renal vein level) that were missed at CT.

Conclusions

CT can accurately identify cavoatrial tumor thrombus that will impact surgical approach. Routine Doppler evaluation, after CT has already been performed, is not required in Wilms tumor. Pediatr Blood Cancer 2012; 58: 551–555. © 2011 Wiley Periodicals, Inc.
Dielectric property and electromagnetic interference shielding effectiveness of ethylene vinyl acetate‐based conductive composites: Effect of different type of carbon fillers
Authors: Sohi N.J.S. , Rahaman M. , Khastgir D.
Published: June 2011

Carbon black, short carbon fiber (SCF), and multiwall carbon nano‐tube (MWNT)‐filled conductive composites were prepared from ethylene vinyl acetate copolymer. The dielectric property and electromagnetic interference (EMI) shielding of carbon black, MWNT, and SCF‐filled composites were studied with different filler loadings. The dielectric constant and loss of filled polymer composites is due to the formation of interfacial polarization in the polymer matrix. It was found that the dielectric constant, dielectric loss, and EMI shielding of filled composites depends on amount and type of filler loading. The results of different experiments have been discussed in the light of break down and formation of continuous conductive network in polymer matrix. The results indicate that these composites can be used as effective EMI shielding materials. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers.
Fetal surgery for cardiac lesions
Authors: Arzt Wolfgang , Tulzer Gerald
Published: June 2011

Intrauterine dilation of critical fetal aortic stenosis (AS) and pulmonary stenosis or atresia has the potential to change the natural course of these congenital heart defects preventing progression to a single ventricle circulation. This article reviews the world experience in fetal cardiac interventions. In carefully selected cases, fetal cardiac surgery can reverse end‐stage heart failure and can provide biventricular outcome postnatally in about two thirds of the cases with successful interventions. Copyright © 2011 John Wiley & Sons, Ltd.
The safe use of insulin e‐learning module: successful roll out of a teaching programme for all working in diabetes
Authors: James J , Atkins H , Sturgess I , Malik R , Rayman G , Morton A , Hillson R , Gregory R
Published: June 2011

Insulin is often used in the management of hyperglycaemia but prescribing and management errors are common. A UK audit revealed 3881 wrong dose incidents and six deaths over six years (National Patient Safety Agency 2010, NPSA). The NPSA and NHS Diabetes launched a tri‐phase education initiative in June 2010, aimed at reducing error and including rapid response reports sent to all hospital and community trusts, written supporting information and recommendations, and access to an e‐learning module and assessment.

The aim of this project was to improve all health care professionals' (HCPs') knowledge in the safe use of insulin through e‐learning.

A safer use of insulin e‐learning module commissioned by NHS Diabetes and the NPSA was developed by a hospital trust and piloted by multidisciplinary HCPs from UK hospital and community settings. Developers used established web‐based contacts to promote access. Reminders were sent to those not completing within three months. The number, type, workplace location and percentage of those accessing and completing the module were audited weekly to assess uptake.

Eight‐month data revealed 31 089 registrations from a wide range of HCPs with 64% (n=19 947) completing. Workplace data showed that more than half of completers worked in secondary care (59%), 22% in primary care, and 19% in community settings. Early data show positive learner feedback.

E‐learning provides an accessible method of education delivery to large multidisciplinary populations; module efficacy can be audited through collection and comparison of locally and nationally reported insulin errors. Copyright © 2011 John Wiley & Sons.
Surface modification using bio‐inspired adhesive polymers based on polyaspartamide derivatives
Authors: An Jung Hyun , Huynh Ngoc Thach , Sil Jeon Young , Kim Ji‐Heung
Published: June 2011

The catechol functional group of dopamine (3,4‐dihydroxyphenethylamine) has the ability to form strong adhesive bonds to inorganic and organic surfaces in aqueous environments. In this study, novel adhesive polyaspartamides containing catechol pendant groups were synthesized from polysuccinimide through successive aminolysis reactions with quantitative dopamine and ethylenediamine. The adhesion and crosslinking of dopamine‐modified polyaspartamide in aqueous alkaline media was used successfully to modify the surface of various materials (including synthetic polymers, metals, metal oxides, ceramics) using a simple immersion method. Contact angle measurements, SEM and X‐ray photoelectron spectroscopy of the modified surfaces were used to verify the surface coating on a variety of materials with very different inherent wetting properties. These novel biocompatible polymers have potential industrial and biomedical applications as adhesives or coating materials for functional surface modification. Copyright © 2011 Society of Chemical Industry
The effect of nanospheres on the permeability of PA6/SiO2 nanocomposites
Authors: Dougnac Vivianne N. , Peoples Brian C. , Quijada Raúl
Published: June 2011

The permeation of O2, N2 and H2O through polyamide‐6 nanocomposites, prepared with silica nanospheres of different diameters, is reported in this contribution. The mechanical and thermal properties were also evaluated. The nanocomposites were produced by melt mixing the polyamide‐6 with silica nanospheres 12–150 nm in diameter, prepared using standard sol‐gel methods; it was found that the addition of 3 wt% of silica nanospheres to the polyamide‐6 matrix results in an increase in the O2 and N2 permeability. This increase was inversely correlated with the nanosphere diameter but directly correlated with the number of spheres added to the matrix, using the same percentage by weight. The same behaviour was found for the water vapour transmission rate. The increase in permeability is probably due to the formation of voids around the particles, which increases the free volume of the polymer. The addition of the nanospheres, regardless of the sphere diameter, generated an increase of 6% in the Young's modulus, a decrease of 65% in the elongation at break and a 24% decrease in the percentage of crystallinity. Copyright © 2011 Society of Chemical Industry
Coating cells with cationic silica–magnetite nanocomposites for rapid purification of integral plasma membrane proteins
Authors: Zhang Wei , Zhao Chao , Wang Sheng , Fang Caiyun , Xu Yawei , Lu Haojie , Yang Pengyuan
Published: June 2011

This study developed a simple and rapid purification method for plasma membrane with high yields from adherent cells. The plasma membrane (PM) sheets could be absorbed specifically by the cationic silica–magnetite nanocomposites (CSMN) under acidic conditions, and recovered directly in cell‐lysis‐buffer with no need for precipitation. The binding between CSMN and PM sheets was confirmed by electron microscopy. Western blot analysis demonstrated a >10‐fold relative enrichment factor. Up to 422 integral membrane proteins were identified from 107 Huh7 cells. Notably, we found 29 Ras family proteins by classification according to their biological functions. The whole enrichment procedure took <30 min. The CSMN‐based procedure demonstrates a simple, economical and efficient enrichment of integral PM proteins in proteomic study.
Biological versus technical variability in 2‐D DIGE experiments with environmental bacteria
Authors: Zech Hajo , Echtermeyer Christoph , Wöhlbrand Lars , Blasius Bernd , Rabus Ralf
Published: June 2011

Two‐dimensional difference gel electrophoresis (2‐D DIGE) allows for reliable quantification of global protein abundance changes. The threshold of significance for protein abundance changes depends on the experimental variation (biological and technical). This study estimates biological, technical and total variation inherent to 2‐D DIGE analysis of environmental bacteria, using the model organisms “Aromatoleum aromaticum” EbN1 and Phaeobacter gallaeciensis DSM 17395. Of both bacteria the soluble proteomes were analyzed from replicate cultures. For strains EbN1 and DSM 17395, respectively, CV revealed a total variation of below 19 and 15%, an average technical variation of 12 and 7%, and an average biological variation of 18 and 17%. Multivariate analysis of variance confirmed domination of biological over technical variance to be significant in most cases. To visualize variances, the complex protein data have been plotted with a multidimensional scaling technique. Furthermore, comparison of different treatment groups (different substrate conditions) demonstrated that variability within groups is significantly smaller than differences caused by treatment.
Proteome reference map of Lactobacillus acidophilus NCFM and quantitative proteomics towards understanding the prebiotic action of lactitol
Authors: Majumder Avishek , Sultan Abida , Jersie‐Christensen Rosa R. , Ejby Morten , Schmidt Bjarne Gregers , Lahtinen Sampo J. , Jacobsen Susanne , Svensson Birte
Published: June 2011

Lactobacillus acidophilus NCFM is a probiotic bacterium adapted to survive in the gastrointestinal tract and with potential health benefits to the host. Lactitol is a synthetic sugar alcohol used as a sugar replacement in low calorie foods and selectively stimulating growth of L. acidophilus NCFM. In the present study the whole‐cell extract proteome of L. acidophilus NCFM grown on glucose until late exponential phase was resolved by 2‐DE (pH 3–7). A total of 275 unique proteins assigned to various physiological processes were identified from 650 spots. Differential 2‐DE (DIGE) (pH 4–7) of L. acidophilus NCFM grown on glucose and lactitol, revealed 68 spots with modified relative intensity. Thirty‐two unique proteins were identified in 41 of these spots changing 1.6–12.7‐fold in relative abundance by adaptation of L. acidophilus NCFM to growth on lactitol. These proteins included β‐galactosidase small subunit, galactokinase, galactose‐1‐phosphate uridylyltransferase and UDP‐glucose‐4‐epimerase, which all are potentially involved in lactitol metabolism. This first comprehensive proteome analysis of L. acidophilus NCFM provides insights into protein abundance changes elicited by the prebiotic lactitol.
Modification of ultra‐high‐molecular weight polyethylene by various fluorinating routes
Authors: Kharitonov Alexander P. , Simbirtseva Galina V. , Bouznik Vyacheslav M. , Chepezubov Maxim G. , Dubois Marc , Guérin Katia , Hamwi Andre , Kharbache Hayat , Masin Francis
Published: June 2011

Chemical–physical properties of ultra‐high‐molecular weight polyethylene (UHMWPE) treated by direct fluorination, direct fluorination accompanied with UV irradiation, by XeF2 and by TbF4, were tested by FTIR spectroscopy, visible spectroscopy, 19F and 13C NMR, scanning electron microscopy, XRD, and EPR. Surface energy measurements were carried out. The direct fluorination of UHMWPE is a diffusion‐controlled process, but treatment with XeF2 is a kinetically controlled one. Direct fluorination and direct fluorination accompanied with UV irradiation results mainly in a formation of CF2 groups. On the contrary, CHF groups are prevailing in UHMWPE treated with XeF2 and TbF4. Surface texture of UHMWPE treated with XeF2 and with F2 is quite different. Direct fluorination results in a higher polarity of the polymer surface when compared with treatment with XeF2. For the case of direct fluorination, both long‐lived peroxy and fluoroalkylradicals are formed. For the case of treatment with XeF2, only fluoroalkylradicals were detected. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 49:3559–3573, 2011
Preparation and properties of ionic‐liquid‐containing poly(ethylene glycol)‐based networked polymer films having lithium salt structures
Authors: Matsumoto Kozo , Endo Takeshi
Published: June 2011

Ionic‐liquid‐containing polymer films were prepared by swelling poly(ethylene glycol)‐based networked polymers having lithium salt structures with an ionic liquid, 1‐ethyl‐3‐methylimidazolium bis(fluorosulfonyl)imide (EMImFSI), or with an EMImFSI solution of lithium bis(trifluoromethanesulfonyl) imide (LiTFSI). Their fundamental physical properties were investigated. The networked polymer films having lithium salt structures were prepared by curing a mixture of poly(ethylene glycol) diglycidyl ether and lithium 3‐glycidyloxypropanesulfonate or lithium 3‐(glycidyloxypropanesulfonyl)(trifluoromethanesulfonyl)imide with poly(ethylene glycol) bis(3‐aminopropyl) terminated. The obtained ionic‐liquid‐containing films were flexible and self‐standing. They showed high ionic conductivity at room temperature, 1.16–2.09 S/m for samples without LiTFSI and 0.29–0.43 S/m for those with 10 wt % LiTFSI. Their thermal decomposition temperature was above 220 °C, and melting temperature of the ionic liquid incorporated in the film was around −16 °C. They exhibited high safety due to good nonflammability of the ionic liquid. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Well‐defined succinylated chitosan‐O‐poly(oligo(ethylene glycol)methacrylate) for pH‐reversible shielding of cationic nanocarriers
Authors: Kang Chengjun , Yu Lin , Cai Guoqiang , Wang Liqun , Jiang Hongliang
Published: June 2011

A novel type of well‐defined graft copolymer, succinylated chitosan‐O‐poly(oligo(ethylene glycol)methacrylate) (SC‐POEGMA), was developed for pH‐reversible poly(ethylene glyocol) (PEG) shielding of cationic nanocarriers. Chitosan‐O‐POEGMA (CS‐POEGMA) was first synthesized via single electron transfer‐living radical polymerization of oligo(ethylene glyol) methacrylate (OEGMA) using O‐brominated chitosan (CS‐Br) as a macromolecular initiator and Cu(I)Br/1,1,4,7,10,10‐hexamethyltriethylenetetramine as a catalyst. The subsequent succinylation of the chitosan backbone gave the titled copolymers. The content of POEGMA in CS‐POEGMA could be widely modulated by varying the degree of bromination and feed ratio of OEGMA to CS‐Br, without compromising the amino density of chitosan backbone. The hierarchical assembly between SC‐POEGMA and trimethylated chitosan‐O‐poly(ε‐caprolactone) (TMC‐PCL) micelles was further studied. At pH 7.4, the stoichiometric interactions between SC and TMC segments to form polyampholyte–polyelectrolyte complexes led to the formation of PEG‐shielded micelles. The hierarchially assembled micelles could be disassembled into the pristine TMC‐PCL micelles, when the medium pH was below a certain pH (pHφ). By varying the degree of succinylation of SC‐POEGMA, the pHφ value could be facilely modulated from 6.5 to 3.5 to meet the needs for specific biomedical applications. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Synthesis and photovoltaic properties of copolymers based on benzo[1,2‐b:4,5‐b′]dithiophene and thiophene with electron‐withdrawing side chains
Authors: Nie Yujuan , Zhao Bin , Tang Peng , Jiang Peng , Tian Zongfang , Shen Ping , Tan Songting
Published: June 2011

Six alternating conjugated copolymers (PL1–PL6) of benzo[1,2‐b:4,5‐b′]dithiophene (BDT) and thiophene, containing electron‐withdrawing oxadiazole (OXD), ester, or alkyl as side chains, were synthesized by Stille coupling reaction. The structures of the polymers were confirmed, and their thermal, optical, electrochemical, and photovoltaic properties were investigated. The introduction of conjugated electron‐withdrawing OXD or formate ester side chain benefits to decrease the bandgaps of the polymers and improve the photovoltaic performance due to the low steric hindrance of BDT. Bulk heterojunction polymer solar cells (PSCs) were fabricated based on the blend of the as‐synthesized polymers and the fullerene derivative [6,6]‐phenyl‐C61‐butyric acid methyl ester (PC61BM) in a 1:2 weight ratio. The maximum power conversion efficiency of 2.06% was obtained for PL5‐based PSC under the illumination of AM 1.5, 100 mW/cm2. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Combined techniques for the characterization of linear–hyperbranched hybrid poly(butylene adipate) copolymers
Authors: Samperi Filippo , Battiato Salvatore , Puglisi Concetto , Scamporrino Andrea , Ambrogi Veronica , Ascione Laura , Carfagna Cosimo
Published: June 2011

Linear–hyperbranched hybrid poly(butylene adipate) (HPBA) copolymers were synthesized through a branching reaction between the linear tailored prepolymer terminated with methyl ester groups and different mol percents of the 1,1,1‐tris(hydroxymethyl) propane (TMP) as branching agent, using the titanium(IV) isopropoxide as catalyst, at 180 °C under vacuum for different times. All samples were characterized by NMR and matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI‐TOF MS). In particular, MALDI‐TOF mass spectra of the unfractionated and size exclusion chromatography (SEC)‐fractionated hyperbranched (HB) samples gave information on their composition, on the end groups as well as on the TMP units present in each family of HB macromolecules. HB chains containing cyclic branches and ether bonds formed by intermolecular transesterification and intramolecular and intermolecular transetherification side reactions, respectively, were also revealed by MALDI‐TOF MS analysis. All samples were also investigated by SEC. The average molar masses (MMs) evaluated by SEC calibrated with the polystyrene (PS) narrow standards were overestimated with respect to those calculated by the SEC/MALDI‐TOF MS self‐ calibration method, which gave reliable values. Moreover, it also showed that the hydrodynamic volume of the HPBA polymers was higher than that of the linear PSs with similar MMs. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Ring‐opening polymerization of 1,3‐benzoxazines by p‐toluenesulfonates as thermally latent initiators
Authors: Sudo Atsushi , Yamashita Hiroshi , Endo Takeshi
Published: June 2011

p‐Toluenesulfonic acid (TsOH) and several alkyl p‐toluenesulfonates, that is, methyl p‐toluenesulfonate (TsOMe), cyclohexyl p‐toluenesulfonate (TsOCH), and neopentyl p‐toluenesulfonate (TsONP), were evaluated as initiators for the ring‐opening polymerization of benzoxazines. TsOH and TsOMe were highly efficient initiators that induced the polymerization at 60 and 80 °C, respectively. In contrast, TsOCH and TsONP did not initiate the polymerization below 100 °C, while they induced the polymerization at elevated temperatures, 120 and 150 °C, respectively. When TsOCH was used as an initiator, the corresponding polymerization rate was comparable to that observed for the polymerization with using TsOH as an initiator. These results suggested that neutral TsOCH and TsONP can be regarded as “thermally latent initiators,” which underwent the thermal dissociation at the elevated temperatures to generate the corresponding alkyl cations and/or TsOH as the initiators of the polymerization. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Triphenylamine‐based polyimides with trimethyl substituents for gas separation membrane and electrochromic applications
Authors: Yen Hung‐ju , Guo Shiue‐ming , Yeh Jui‐ming , Liou Guey‐Sheng
Published: June 2011

Two series of polyimides I–II with methyl‐substituted triphenylamine units were prepared from the diamines, 4,4′‐diamino‐2″,4″,6″‐trimethyltriphenylamine (Me3TPA‐diamine; 1) and 4,4′‐diamino‐4″‐methyltriphenylamine (MeTPA‐diamine; 2), and two commercially available tetracarboxylic dianhydrides via a conventional two‐step chemical imidization. All the polymers were readily soluble in many polar solvents and showed useful levels of thermal stability associated with high glass transition temperatures (266–340 °C) and high char yields (higher than 49% at 800 °C in nitrogen). The polymer films showed reversible electrochemistry/electrochromism accompanied by a color change from neutral pale yellow to green oxidized form with good coloration efficiency, switching time, and stability. The CO2 permeability coefficients (PCO2) and permeability selectivity (PCO2/PCH4) for these polyimide membranes were in the range of 34.1–229.2 barrer and 21.3–28.9, respectively. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Method for rapid detection of the PvCesA3 gene allele conferring resistance to mandipropamid, a carboxylic acid amide fungicide, in Plasmopara viticola populations
Authors: Aoki Yoshinao , Furuya Seiichi , Suzuki Shunji
Published: June 2011

BACKGROUND: The occurrence of carboxylic acid amide (CAA)‐fungicide‐resistant Plasmopara viticola populations is becoming a serious problem in the control of grapevine downy mildew worldwide.

RESULTS: The authors have developed a method, which utilises PCR‐RFLP, for the rapid detection of resistance to the CAA fungicide mandipropamid in P. viticola populations. With this method, a glycine‐to‐serine substitution at codon 1105 of the cellulose synthase gene PvCesA3 of CAA‐fungicide‐resistant P. viticola was easily detected, although no resistant P. viticola was detected from 398 isolates in Japan.

CONCLUSION: It is proposed that the PCR‐RFLP method is a reliable tool for the rapid detection of CAA‐fungicide‐resistant P. viticola isolates. Only 4 h was required from the sampling of symptoms to the phenotyping of fungicide resistance. Copyright © 2011 Society of Chemical Industry
Structural characterization of CuInS2 thin films from Cu–In metal inks
Authors: Chen Guanbi , Wang Lei , Sheng Xia , Chang Lantao , Luo Yeping , Yang Deren
Published: June 2011

We report the structural characterization of CuInS2 thin films based on Cu–In metal inks. CuInS2 films from the precursor films with different Cu/In ratios were sulfurized and investigated by SEM, XRD, Raman, and XPS. Morphological and compositional changes before and after etching of CuS impurity phase were also compared. By ex situ characterization of the CuInS2 films sulfurized at different temperatures, an established mechanism is proposed to explain the sulfurization process. The sulfurization is a diffusion‐limited process, in which the diffusion rate differences of Cu and In control the intermediate phases. Moreover, the Cu/In ratio and sulfurization temperature determine the morphological and structural qualities of the CuInS2 films.
Edge‐field effects on gate capacitance, threshold voltage and low‐field mobility in AlGaN/GaN HEMTs
Authors: Kim Hyeongnam , Schuette Michael L. , Lu Wu
Published: June 2011

A methodologybased on output conductance model and pulsed current–voltage characteristics is presented for device parameter extraction in AlGaN/GaN HEMTs. A quiescent bias of (VDSQ, VGS Q) = (0 V, 0 V) and 0.2 µs pule width with 2 ms separation are applied to ensure that all the pulsed measurementsare performed under trap‐free operation condition.The results show that HEMTs with a shorter gate length exhibit a more negative threshold voltage, a lower low‐field mobility, and a higher capacitance than the theoretical AlGaN barrier capacitance. This is because edge field effect becomes significant in a shorter gate together with a higher lateral field effect. By comparing the measured and theoretical capacitances of AlGaN barrier, effective gate lengths are also estimated for HEMTs with different gate lengths. It is suggested that our method including the edge‐field effect is an effective way for evaluating newly‐introduced growth/processing technologies and monitoring device processing (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Macroscopic response of Rabi oscillations in a quantum dot ensemble
Authors: Mitsutake S. , Kujiraoka M. , Ishi‐Hayase J. , Akahane K. , Yamamoto N. , Ema K. , Sasaki M.
Published: June 2011

We numerically investigated optical Rabi oscillations of excitonic polarization in a quantum dot ensemble, taking into consideration the spatial distribution of both the excitation electric field and the coherent signal field. We show that the spatial distributions of the signal fields change drastically by increasing the pulse area for excitation pulses with a Gaussian spatial distribution. We found that the ensemble average of the signal intensity is affected by the size of the aperture located in front of the detector, depending on the spatial distribution of the signals on the detector. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
EPR investigations of non‐oxidized silicon nanoparticles from thermal pyrolysis of silane
Authors: Körmer Richard , Otto Michael , Wu Jia , Jank Michael P. M. , Frey Lothar , Peukert Wolfgang
Published: June 2011

Electron paramagnetic resonance (EPR) investigations of non‐oxidized crystalline silicon nanoparticles (SiNP) from thermal silane pyrolysis revealed that the dangling bond (db) concentration strongly depends on the synthesis temperature. For SiNP synthesized at 1000‐1200 °C and processed entirely in inert atmosphere, approximately 1013 cm‐2 dbs were found which is at least one order of magnitude higher than the values previously reported for oxidized SiNP. After the synthesis, the dbs can be quenched by the addition of bromine (Br2) that proves their location at the particle surface. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Morphology controlled open circuit voltage in polymer solar cells
Authors: Singh Chetan R. , Sommer Michael , Himmerlich Marcel , Wicklein André , Krischok Stefan , Thelakkat Mukundan , Hoppe Harald
Published: June 2011

We report a strong dependence of open circuit voltage on the altered morphology of block copolymer (P3HT‐b ‐PPerAcr) based solar cells. The open circuit voltage increases dramatically by about 300 mV by increasing the amount of acceptor homopolymer within the block copolymer/homopolymer blends. The change in open circuit voltage is found to be in correlation with the enrichment of acceptor moiety at the film surface as identified by Atomic force microscopy (AFM) and X‐ray photoelectron spectroscopy (XPS). Based on this fact, an additional increase in open circuit voltage to its maximum values is achieved by introducing an acceptor buffer layer at the cathode interface. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of Total Glycosides from Eucommia ulmoides Seed on Bone Microarchitecture in Rats
Authors: Li Yang , Wang Min‐juan , Li Sen , Zhang Yong‐min , Zhao Ye , Xie Ren‐ming , Sun Wen‐ji
Published: June 2011

Du‐Zhong is one of the most important tonic herbs in traditional Chinese medicine for the treatment of bone fractures and other bone diseases. The present study examined whether Du‐Zhong seed extract named total glycosides from Eucommia ulmoides seed (TGEUS) could display an increased effect on bone density and bone strength of the femur in rats. Sprague–Dawley rats were used and randomly assigned to the normal group and the TGEUS group (400 mg/kg body weight/day). Daily oral administration of TGEUS was found to increase significantly the biomechanical quality of the femur. The mechanical changes were associated with a bone mineral density (BMD) increase or even with some improvements in microarchitecture. Micro‐CT analysis of the distal femur showed that TGEUS significantly increased the bone volume/tissue volume (BV/TV), connectivity density (Conn.D), trabecular number (Tb.N) and trabecular thickness (Tb.Th), and decreased trabecular separation (Tb.Sp) and the structure model index (SMI) in normal rats. To conclude, TGEUS taken orally increased bone density and altered bone histomorphology, suggesting that TGEUS might be a potential alternative medicine for the treatment of postmenopausal osteoporosis. Copyright © 2011 John Wiley & Sons, Ltd.
Performance evaluation on a wide set of matrix‐assisted laser desorption ionization matrices for the detection of oligosaccharides in a high‐throughput mass spectrometric screening of carbohydrate depolymerizing enzymes
Authors: Ropartz David , Bodet Pierre‐Edouard , Przybylski Cédric , Gonnet Florence , Daniel Régis , Fer Maude , Helbert William , Bertrand Dominique , Rogniaux Hélène
Published: June 2011

Compared to other analytical methods, matrix‐assisted laser desorption ionization mass spectrometry (MALDI‐MS) presents several unique advantages for the structural characterization of degradation products of carbohydrates. Our final goal is to implement this technique as a high‐throughput platform, with the aim of exploring natural bio‐diversity to discover new carbohydrate depolymerizing enzymes. In this approach, a variety of carbohydrates will be used as enzymes substrates and MALDI‐MS will be employed to monitor the oligosaccharides produced. One drawback of MALDI, however, is that the choice of the matrix is largely dependent on the chemical properties of the analyte. In this context, our objective in the present work was to find the smallest set of MALDI matrices able to detect chemically heterogeneous oligosaccharides. This was done through the performance evaluation of more than 40 MALDI matrices preparations. Homogeneity of analyte‐matrix deposits was considered as a critical feature, especially since the final objective is to fully automate the analyses. Evaluation of the matrices was done by means of a rigorous statistical approach. Amongst all tested compounds, our work proposes the use of the DHB/DMA ionic matrix as the most generic matrix, for rapid detection of a variety of polysaccharides including neutral, anionic, methylated, sulfated, and acetylated compounds. The selected matrices were then used to screen crude bacterial incubation media for the detection of enzymatic degradation products. Copyright © 2011 John Wiley & Sons, Ltd.
High‐performance liquid chromatography‐diode array detection‐electrospray ionization multi‐stage mass spectrometric screening of an insect/plant system: the case of Spodoptera littoralis/Lycopersicon esculentum phenolics and alkaloids
Authors: Ferreres Federico , Taveira Marcos , Gil‐Izquierdo Angel , Oliveira Luísa , Teixeira Tânia , Valentão Patrícia , Simões Nelson , Andrade Paula B.
Published: June 2011

High‐performance liquid chromatography‐diode array detection‐electrospray ionization multi‐stage mass spectrometry (HPLC‐DAD‐ESI‐MSn) is considered to be a very valuable tool for the characterization of compounds found in trace amounts in natural matrices, as their previous isolation and clean‐up steps can be avoided. Micro‐scale separation increases the potential of this analytical technique, allowing the determination of compounds in reduced samples. Spodoptera littoralis represents a major challenge to Solanaceae plants, as it is one of the most deleterious pests. The S. littoralis/Lycopersicon esculentum system was studied for the first time concerning glycoalkaloids and phenolics. Using HPLC‐DAD‐ESI‐MSn we were able to characterize 15 phenolic compounds in L. esculentum leaves. Nine of them are reported for the first time. Some differences were found between leaves of cerasiforme and 'Bull's heart' varieties. However, in the materials of S. littoralis (larvae, adults, exuviae and excrements) reared in both L. esculentum leaves no phenolics were identified. α‐Tomatine was the main glycoalkaloid in the host plant. The glycoalkaloid composition of the different S. littoralis materials was distinct, with α‐tomatine and dehydrotomatine being the main detected compounds in larvae and excrements. These results add knowledge to the ecological interaction in this insect/plant duo, for which it is hard to obtain considerable sample amounts. Copyright © 2011 John Wiley & Sons, Ltd.
Elimination of the helium requirement in high‐field asymmetric waveform ion mobility spectrometry (FAIMS): beneficial effects of decreasing the analyzer gap width on peptide analysis
Authors: Barnett David A. , Ouellette Rodney J.
Published: June 2011

Cylindrical geometry high‐field asymmetric waveform ion mobility spectrometry (FAIMS) focuses and separates gas‐phase ions at atmospheric pressure and room (or elevated) temperature. Addition of helium to a nitrogen‐based separation medium offers significant advantages for FAIMS including improved resolution, selectivity and sensitivity. Aside from gas composition, ion transmission through FAIMS is governed by electric field strength (E/N) that is determined by the applied voltage, the analyzer gap width, atmospheric pressure and electrode temperature. In this study, the analyzer width of a cylindrical FAIMS device is varied from 2.5 to 1.25 mm to achieve average electric field strengths as high as 187.5 Townsend (Td). At these electric fields, the performance of FAIMS in an N2 environment is dramatically improved over a commercial system that uses an analyzer width of 2.5 mm in 1:1 N2/He. At fields of 162 Td using electrodes at room temperature, the average effective temperature for the [M + 2 H]2+ ion of angiotensin II reaches 365 K. This has a dramatic impact on the curtain gas flow rate, resulting in lower optimum flows and reduced turbulence in the ion inlet. The use of narrow analyzer widths in a N2 carrier gas offers previously unattainable baseline resolution of the [M + 2 H]2+ and [M + 3 H]3+ ions of angiotensin II. Comparisons of absolute ion current with FAIMS to conventional electrospray ionization (ESI) are as high as 77% with FAIMS versus standard ESI‐MS. Copyright © 2011 John Wiley & Sons, Ltd.
The protein profile of Theobroma cacao L. seeds as obtained by matrix‐assisted laser desorption/ionization mass spectrometry
Authors: Bertazzo Antonella , Agnolin Fabio , Comai Stefano , Zancato Mirella , Costa Carlo V. L. , Seraglia Roberta , Traldi Pietro
Published: June 2011

The water‐soluble protein profile of the seeds of green, red, and yellow Theobroma cacao L. fruits has been determined by matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐ToF‐MS). The seeds were powdered under liquid nitrogen and defatted. The residues were dialyzed and lyophilized. The obtained samples were suspended in the matrix solution of sinapinic acid. The obtained MALDI mass spectra showed the presence of a wide number of proteins with molecular weight ranging from 8000 to 13 000 Da and a cluster of peaks centered at 21 000 Da that were attributed to albumin. The abundance of this peak was found to depend on the different portion of the seed (husk, apical and cortical parts); however, the MALDI mass spectra obtained from the different varieties of cocoa were practically superimposable. Changes in the protein profiles were also observed after the cocoa seeds were treated by fermentation and roasting, which are processes usually employed for the commercial production of cocoa. Copyright © 2011 John Wiley & Sons, Ltd.
Automated parameter specification in dynamic feedback models based on behavior pattern features
Authors: Yücel Gönenç , Barlas Yaman
Published: June 2011

In various stages of a modeling study, the developer/user encounters the need for identification of specific values for certain model parameters. However, due to the non‐linear nature of these models it is generally hard to foresee changes in the dynamic behavior as a consequence of even marginal parameter changes. Thus, the need for an automated and efficient search approach is very clear. A behavior pattern‐based parameter search approach and results obtained from various test experiments are presented in this paper. The pattern identification algorithm used enables a parameter search process based on qualitative features of a desired behavior pattern, even in the absence of a reference data series. The approach conducts the search process so as to obtain values for the model parameters that yield an output that matches the desired behavior in terms of its qualitative pattern features. Experiments conducted reveal the viability of the approach as a support tool that can be used in model calibration, sensitivity analysis, validation, and policy design stages. Copyright © 2011 System Dynamics Society.
Pairing‐based strong designated verifier proxy signature scheme with low cost
Authors: Hsu Chien‐Lung , Lin Han‐Yu
Published: June 2011

A proxy signature (PS) scheme has crucial benefits to the delegation operations in an organization. To further provide PS schemes with the property of confidentiality, in this paper, we propose a strong designated verifier PS scheme from pairings. The proposed scheme allows an authorized proxy signer to generate a valid PS on behalf of an original signer such that only the intended verifier is capable of validating it. Besides, the designated verifier cannot transfer the proof to convince any third party, which is referred to as non‐transferability. Compared with previous works, ours has lower computational costs. Especially, the delegation process of our proposed scheme is pairing free. Moreover, the security requirement of unforgeability against existential forgery under adaptive chosen‐message attacks is formally proven in the random oracle model. Copyright © 2011 John Wiley & Sons, Ltd.
ATR‐FTIR Kretschmann spectroscopy for interfacial studies of a hidden aluminum surface coated with a silane film and epoxy II. Analysis by integrated ATR‐FTIR and EIS during exposure to electrolyte with complementary studies by in situ ATR‐FTIR and in situ IRRAS
Authors: Öhman Maria , Persson Dan
Published: June 2011

The destabilization of the interface between a polymer and a metal surface is of considerable interest in several application areas, including the ongoing research on environmentally friendly pretreatments as a replacement for the Cr(VI)‐containing systems where the understanding of mechanisms and performance of a confined metal/polymer interface is of utmost importance. Processes at hidden interfaces are, however, difficult to analyze in detail and at relevant climatic conditions. This study has been divided in two parts, where the subject of Part I is the surface characterization by ATR‐FTIR Kretschmann and IRRAS spectroscopy of aluminum coated with an amino‐functional silane, and the interfacial analysis by ATR‐FTIR Kretschmann after further application of an epoxy film. This second part describes the interaction between the coated sample and an electrolyte. The analysis is performed by integrated in situ ATR‐FTIR Kretschmann and EIS, which requires model systems with evaporated metal films on an internal reflection element. Complementary analyses were also conducted on substrates in the absence of the metal film, and or in the absence of an epoxy top‐coat, respectively. Changes in the interfacial region were observed and assigned to the water uptake including swelling of the epoxy, and the formation of aluminium oxidation and hydration products. Complementary studies allowed the distinction between water uptake in the silane film and the epoxy, respectively, as well as reformations of the siloxane network. Copyright © 2011 John Wiley & Sons, Ltd.
On the Lifecycle of Nanocomposites: Comparing Released Fragments and their In‐Vivo Hazards from Three Release Mechanisms and Four Nanocomposites
Authors: Wohlleben Wendel , Brill Sandra , Meier Matthias W. , Mertler Michael , Cox Gerhard , Hirth Sabine , von Vacano Bernhard , Strauss Volker , Treumann Silke , Wiench Karin , Ma‐Hock Lan , Landsiedel Robert
Published: June 2011

Nanocomposites are the dominating class of nanomaterials to come into consumer contact, and were in general assumed to pose low risk. The first data is now emerging on the exposure from nanocomposites, but little is yet known about their hypothetical nanospecific physiological effects, giving ample room for speculation. For the first time, this comprehensive study addresses these aspects in a systematic series of thermoplastic and cementitious nanocomposite materials. Earlier reports that ‘chalking’, the release of pigments from weathered paints, also occurs for nanocomposites, are confirmed. In contrast, mechanical forces by normal consumer use or do‐it‐yourself sanding do not disrupt nanofillers (nanoparticles or nanofibers) from the matrix. Detailed evidence is provided for the nature of the degradation products: no free nanofillers are detected up to the detection threshold of 100 ppm. Sanding powders measuring 1 to 80 μm in diameter are identified with the original material, still containing the nanofillers. The potential hazard from aerosols generated by sanding nanocomposites up to the nuisance dust limit is also investigated. In‐vivo instillation in rats is used to quantify physiological effects on degradation products from abraded nanocomposites, in comparison to the abraded matrix without nanofiller and to the pure nanofiller. In this pioneering and preliminary evaluation, the hazards cannot be distinguished with or without nanofiller.