bluuebunny/crossref_metadata_2025 huggingface dataset:
Photothermal response of superparamagnetic iron oxide nanoparticles
Authors: Kim Jihoon , Oh Junghwan , Kang Hyun Wook , Feldman Marc D. , Milner Thomas E.
Published: July 2008

Background and Objective

Superparamagnetic iron oxide nanoparticles have been used as MRI contrast agents in medical imaging. The purpose of this study was to explore the photothermal response of superparamagnetic iron oxide nanoparticles for biomedical applications.

Study Design/Materials and Methods

Absorbance, temperature increase, and optical path length change of solutions of superparamagnetic iron oxide nanoparticles, SPIO and MION, in response to a 532 nm pulsed laser irradiation were measured.

Results

Both SPIO and MION showed absorption at 532 nm, temperature increase, and optical path length change. SPIO and MION underwent selective heating due to absorption of laser energy (532 nm).

Conclusion

Temperature increase and optical path length change of SPIO and MION in response to 532 nm pulsed laser irradiation demonstrate a potential application of these particles in biomedical imaging. For further study, additional experiments applying the photothermal response of SPIO and MION in tissues are required. Lesers Surg. Med. 40:415–421, 2008. © 2008 Wiley‐Liss, Inc.
Successful treatment of acneiform scarring with CO2ablative fractional resurfacing
Authors: Chapas Anne M. , Brightman Lori , Sukal Sean , Hale Elizabeth , Daniel David , Bernstein Leonard J. , Geronemus Roy G.
Published: July 2008

Background

Acneiform scarring after severe episodes of acne is a common cosmetic concern, treatable by a variety of modalities with varying degrees of success. Ablative CO2laser resurfacing, while effective, is associated with an undesirable side effects profile, lengthy recovery period, and risk of infection as well as potential pigmentary alterations. Newer modalities using the principles of fractional photothermolysis (FP) create patterns of tiny microscopic wounds surrounded by undamaged tissue beneath the skin with an erbium‐doped 1,550 nm laser. These devices produce more modest results in many cases than traditional carbon dioxide (CO2) lasers but with fewer side effects and shorter recovery periods. A novel ablative 30 W CO2laser device uses a technique called ablative fractional resurfacing (AFR), combines CO2ablation with a FP system.

Methods

Thirteen subjects (skin types I–IV, aged 28–58 years) with moderate to severe acne scars underwent two or three treatments with the AFR device at 1–2 months intervals. Post‐treatment erythema and edema as well as improvements in texture, atrophy, and overall satisfaction with appearance were graded on a quartile scale by subjects and investigators after each treatment and 1 and 3 months after the final treatment. Petechiae, oozing and crusting, dyschromia, and scarring were graded as present or absent 3 days, 1 week, 1 month, and 3 months following each treatment. A three‐dimensional optical profiling system (Primos imaging) was used to generate a high resolution topographic representation of the acneiform scar in order to measure the depths of 10 scars from each cheek prior to the first treatment and 3 months after the last treatment.

Results

Post‐treatment side effects were mild to moderate and transient, resolving rapidly within the study period. No delayed onset hypo‐pigmentation or permanent scarring was observed. Quartile grading scores correlating to at least 26–50% improvements in texture, atrophy, and overall improvement were noted in all patients. Primos topographic analysis showed that all patients had quantifiable objective improvement in the depths of acneiform scars that ranged from 43% to 79.9% with a mean level of improvement of 66.8%.

Conclusion

Successfully combining ablative technology with FP, AFR treatments constitute a safe and effective treatment modality for acneiform scarring. Lesers Surg. Med. 40:381–386, 2008. © 2008 Wiley‐Liss, Inc.
A Conjugated Polymer‐Based Electrochemical DNA Sensor: Design and Application of a Multi‐Functional and Water‐Soluble Conjugated Polymer
Authors: Zhang Lanyong , Sun Huan , Li Di , Song Shiping , Fan Chunhai , Wang Shu
Published: July 2008

In this work, we report the design of a new multi‐functional, water‐soluble conjugated polymer integrating both a DNA intercalator and a redox label. Based on this multi‐functional conjugated polymer, we develop a sequence‐specific electrochemical DNA sensor, where the acridine unit serves as the basis for sequence discrimination, and the ferrocene label provides the electrochemical signal. Moreover, the conjugated polythiophene helps transfer electrons from ferrocene to the electrode. This sensor provides a new way for rapid and convenient detection of DNA targets.

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Reversal of head drop after discontinuation of olanzapine in a DLB patient
Authors: Aries Marcel J.H. , Debruyne Hans , Engelborghs Sebastiaan , Le Bastard Nathalie , Somers Nore , Gorissen Dagmar , Pickut Barbara A. , De Deyn Peter Paul
Published: July 2008

We present a 72‐year‐oldpatient with probable diffuse Lewy body disease and visual hallucinations, who developed subacute reversible “dropped head syndrome” and parkinsonian signs after the introduction of olanzapine at a total daily dose of 10 mg. One week after olanzapine was withdrawn, the patient's posture started to improve. Further improvement was achieved after dopaminergic substitution. Clinical and electrophysiological observations might indicate neck extensor myopathy due to axial rigidity or focal neck dystonia, induced by dopamine receptor blockade. © 2008 Movement Disorder Society
Elevated serotonin transporter binding in depressed patients with Parkinson's disease: A preliminary PET study with [11C]DASB
Authors: Boileau Isabelle , Warsh Jerry J. , Guttman Mark , Saint‐Cyr Jean A. , McCluskey Tina , Rusjan Pablo , Houle Sylvain , Wilson Alan A. , Meyer Jeffrey H. , Kish Stephen J.
Published: July 2008

This study investigated whether abnormalities in serotonin transporter binding occur in Parkinson's disease (PD) patients with concurrent depression. We estimated serotonin transporter levels in seven clinically depressed early‐stage PD patients and in seven healthy matched‐control subjects during a single positron emission tomography (PET) scan with the serotonin transporter radioligand, [11C]DASB. Depressed PD patients displayed a wide‐spread increase (8–68%) in [11C]DASB specific binding outside of the striatum, which was significant in dorsolateral (37%) and prefrontal (68%) cortices. Elevated [11C]DASB binding was positively correlated with depressive symptoms but not with disease severity or duration. Compatible with recent PET/[11C]DASB findings in major depression, the present preliminary data suggest that increased [11C]DASB binding, possibly reflecting greater serotonin transporter density (up‐regulation), might be a pathological feature of depression in Parkinson's disease—and possibly a characteristic of depressive illness in general. © 2008 Movement Disorder Society
What relation is there between deep brain stimulation and coping strategies in Parkinson's disease?
Authors: Montel Sébastien , Bungener Catherine
Published: July 2008

We investigated the effect of the deep brain stimulation (DBS) on coping strategies while taking depression into account. Patients with Parkinson's disease (PD) were divided into three groups matched for sex, age, and disease severity: one, just before DBS, another at 12 months post DBS, and a group of patients not being considered for DBS. Each patient was asked to complete two self‐reports about their coping styles: The ways of coping check list and the coping with health, injuries, and problems scale. The Montgomery and Asberg depression rating scale was assessed by a psychologist. After control for depression, significant differences were noticed concerning two coping strategies: instrumental (P < 0.01) and emotional (P < 0.05) ones, with higher instrumental coping strategies (seeking more information) for patients prior DBS and higher emotional strategies (avoidance, emotional preoccupation) for patients not being considered for surgery. These results confirmed our clinical impression that coping strategies differ as a function of the surgical status of PD patients. © 2008 Movement Disorder Society.
Swept‐frequency two‐pulse phase modulation (SWf‐TPPM) sequences with linear sweep profile for heteronuclear decoupling in solid‐state NMR
Authors: Vinod Chandran C. , Madhu P. K. , Kurur Narayanan D. , Bräuniger Thomas
Published: July 2008

Recently, a pulse scheme for heteronuclear spin decoupling in solid‐state NMR, called swept‐frequency two‐pulse phase modulation (SWf‐TPPM), was introduced which outperforms the standard TPPM and small phase incremental alteration (SPINAL) schemes. It has also been shown that the frequency‐sweep profile can be varied to achieve optimal efficiency for crystalline and liquid‐crystalline samples, respectively. Here we present a detailed comparison of the proton decoupling performance for SWf‐TPPM sequences with tangential sweep profiles (SWftan‐TPPM) and linear sweep profiles (SWflin‐TPPM). Using the 13CH2 resonance of crystalline tyrosine as a model system, it is shown that linear profiles have a decoupling performance which is at least as good and in some instances slightly better than that obtained from tangential sweep profiles. While tangential sweep profiles require a tangent cut‐off angle as an additional parameter, the lack of that parameter makes linear sweep profiles easier to implement and optimise. Copyright © 2008 John Wiley & Sons, Ltd.
Prospective double‐blind crossover trial of ibuprofen in reducing EMG pain
Authors: El‐Salem Khalid , Shakhatreh Mohammad
Published: July 2008

To test the efficacy of ibuprofen in reducing needle electromyography (EMG) pain we studied 30 healthy volunteers randomized to receive placebo or ibuprofen (400 mg) 2 h before EMG using concentric needle electrodes in four muscles. The electromyographer and volunteer were both blinded. Immediately after EMG, subjects reported their experience of pain on a visual analog scale (VAS). A day later, they filled a VAS for their memory of pain during EMG and a VAS for the residual pain at needle sites. A week later, subjects were crossed over and the same procedure was repeated on the same muscles of the contralateral limbs. Immediate recall of pain was significantly decreased by ibuprofen, but memory of pain and residual needle site pain a day after EMG were not decreased. We conclude that ibuprofen is effective in reducing EMG pain as perceived immediately after the procedure. Premedication with ibuprofen before EMG is useful. Muscle Nerve, 2008
Chemical sympathectomy further increases muscle protein degradation of acutely diabetic rats
Authors: Baviera Amanda Martins , Zanon Neusa Maria , Navegantes Luiz Carlos C. , Migliorini Renato Hélios , Kettelhut Isis C.
Published: July 2008

The present work investigated the role of the sympathetic nervous system (SNS) in the control of protein degradation in skeletal muscles from rats with streptozotocin (STZ)‐induced diabetes. Diabetes (1, 3, and 5 days after STZ) induced a significant increase in the norepinephrine content of soleus and EDL muscles, but it did not affect plasma catecholamine levels. Chemical sympathectomy induced by guanethidine (100 mg/kg body weight, for 1 or 2 days) reduced muscle norepinephrine content to negligible levels (less than 5%), decreased plasma epinephrine concentration, and further increased the high rate of protein degradation in muscles from acutely diabetic rats. The rise in the rate of proteolysis (nmol.mg wet wt−1.2h−1) in soleus from 1‐day diabetic sympathectomized rats was associated with increased activities of lysosomal (0.127 ± 0.008 vs. 0.086 ± 0.013 in diabetic control) and ubiquitin (Ub)‐proteasome‐dependent proteolytic pathways (0.154 ± 0.007 vs. 0.121 ± 0.006 in diabetic control). Increases in Ca2+‐dependent (0.180 ± 0.007 vs. 0.121 ± 0.011 in diabetic control) and Ub‐proteasome‐dependent proteolytic systems (0.092 ± 0.003 vs. 0.060 ± 0.002 in diabetic control) were observed in EDL from 1‐day diabetic sympathectomized rats. The lower phosphorylation levels of AKT and Foxo3a in EDL muscles from 3‐day diabetic rats were further decreased by sympathectomy. The data suggest that the SNS exerts acute inhibitory control of skeletal muscle proteolysis during the early stages of diabetes in rats, probably involving the AKT/Foxo signaling pathway. Muscle Nerve, 2008
Explicit finite element perfectly matched layer for transient three‐dimensional elastic waves
Authors: Basu Ushnish
Published: July 2008

The use of a perfectly matched layer (PML) model is an efficient approach toward the bounded‐domain modelling of wave propagation on unbounded domains. This paper formulates a three‐dimensional PML for elastic waves by building upon previous work by the author and implements it in a displacement‐based finite element setting. The novel contribution of this paper over the previous work is in making this finite element implementation suitable for explicit time integration, thus making it practicable for use in large‐scale three‐dimensional dynamic analyses. An efficient method of calculating the strain terms in the PML is developed in order to take advantage of the lack of the overhead of solving equations at each time step. The PML formulation is studied and validated first for a semi‐infinite bar and then for the classical soil–structure interaction problems of a square flexible footing on a (i) half‐space, (ii) layer on a half‐space and (iii) layer on a rigid base. Numerical results for these problems demonstrate that the PML models produce highly accurate results with small bounded domains and at low computational cost and that these models are long‐time stable, with critical time step sizes similar to those of corresponding fully elastic models. Copyright © 2008 John Wiley & Sons, Ltd.
A TLM method for steady‐state convection–diffusion: Some additions and refinements
Authors: Kennedy Alan , O'Connor William J.
Published: July 2008

A recent paper introduced a novel and efficient scheme, based on the transmission line modelling (TLM) method, for solving steady‐state convection–diffusion problems. This paper shows how this one‐dimensional scheme can be adapted to include reaction and source terms and how it can be implemented with non‐equidistant nodes. It introduces new ways of calculating the necessary model parameters which can improve the accuracy of the scheme, shows how steady‐state solutions can be obtained directly, and compares results with those from two finite difference (FD) methods. While the cost of implementation is higher than for the FD schemes, the new TLM scheme can be significantly more accurate, especially when convection dominates. Copyright © 2008 John Wiley & Sons, Ltd.
Reliability and validity of the Sexual Pressure Scale for Women‐Revised
Authors: Jones Rachel , Gulick Elsie
Published: July 2008

Sexual pressure among young urban women represents adherence to gender stereotypical expectations to engage in sex. Revision of the original five‐factor Sexual Pressure Scale was undertaken in two studies to improve reliabilities in two of the five factors. In Study 1 the reliability of the Sexual Pressure Scale for Women‐Revised (SPSW‐R) was tested, and principal components analysis was performed in a sample of 325 young, urban women. A parsimonious 18‐item, four‐factor model explained 61% of the variance. In Study 2 the theory underlying sexual pressure was supported by confirmatory factor analysis using structural equation modeling in a sample of 181 women. Reliabilities of the SPSW‐R total and subscales were very satisfactory, suggesting it may be used in intervention research. © 2008 Wiley Periodicals, Inc. Res Nurs Health 32:71–85, 2009
A novel depolymerization of nylons in ionic liquids
Authors: Kamimura Akio , Yamamoto Shigehiro
Published: July 2008

Treatment of a polyamide such as Nylon‐6 in ionic liquids at 300°C resulted in the effective depolymerization to monomeric amides, which were readily isolated through direct distillation from the reaction pot. The ionic liquids were recycled and they still worked as good reaction media after being used five times. The present method provides a new usage of ionic liquids that will serve as a key material for realizing zero‐emission chemical recycling process of plastics. Copyright © 2008 John Wiley & Sons, Ltd.
Antibacterial effect of silver nanoparticles deposited on corona‐treated polyester and polyamide fabrics
Authors: Radetić Maja , Ilić Vesna , Vodnik Vesna , Dimitrijević Suzana , Jovančić Petar , Šaponjić Zoran , Nedeljković Jovan M.
Published: July 2008

The possibility of using a corona treatment (electrical discharge at atmospheric pressure) for fiber surface activation, which can facilitate the loading of silver nanoparticles (NPs) from colloids onto the polyester (PES) and polyamide (PA) fabrics and thus improve their antibacterial properties, was studied. Bactericidal efficiency and its laundering durability on silver‐loaded fabrics for Gram‐positive bacteriumStaphylococcus aureusand Gram‐negative bacteriumEscherichia coliwere evaluated. The fiber morphology after corona treatment and subsequent loading of silver NPs was followed by SEM. Corona‐treated fabrics loaded with silver NPs exhibited better antibacterial properties in comparison with untreated fabrics. In order to obtain acceptable laundering durability, it is necessary to use highly concentrated silver colloids. Copyright © 2008 John Wiley & Sons, Ltd.
Expression of G protein‐coupled receptor kinase 4 is associated with breast cancer tumourigenesis
Authors: Matsubayashi J , Takanashi M , Oikawa K , Fujita K , Tanaka M , Xu M , Blasi A De , Bouvier M , Kinoshita M , Kuroda M , Mukai K
Published: July 2008

G‐protein‐coupled receptor kinases (GRKs) comprise a family of seven mammalian serine/threonine protein kinases that phosphorylate and regulate agonist‐bound, activated, G‐protein‐coupled receptors (GPCRs). GRKs and β‐arrestins are key participants in the canonical pathways leading to phosphorylation‐dependent GPCR desensitization, endocytosis, intracellular trafficking and resensitization. Here we show that GRK4 isoforms are expressed in human breast cancer but not in normal epithelia. In addition, GRK4‐over‐expressing cells activated the mitogen‐activated protein kinase (MAPK) mediated by ERK 1/2 and JNK phosphorylation in breast cancer‐derived cell lines. Furthermore, suppression of β‐arrestins decreased GRK4‐stimulated ERK 1/2 or JNK phosphorylations. These data indicate that high‐level expression of GRK4 may activate MAPK signalling pathways mediated by β‐arrestins in breast cancer cells, suggesting that GRK4 may be implicated in breast cancer carcinogenesis. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
A prospective, randomized study comparing cefozopran with piperacillin–tazobactam plus ceftazidime as empirical therapy for febrile neutropenia in children with hematological disorders
Authors: Sato Tomonobu , Kobayashi Ryoji , Yasuda Kazue , Kaneda Makoto , Iguchi Akihiro , Kobayashi Kunihiko
Published: July 2008

Background

The aim of this randomized study was to evaluate the efficacy of cefozopran monotherapy and piperacillin–tazobactam plus ceftazidime (PIPC/TAZ + CAZ) combination therapy in pediatric neutropenic patients.

Procedure

A total of 51 patients with 138 episodes of febrile neutropenia received antibiotic therapy. Of these episodes, 95 were considered eligible for the study. The episodes were treated randomly with either piperacillin–tazobactam (125 mg/kg/day) plus ceftazidime (100 mg/kg/day) or with cefozopran (100 mg/kg/day). Success was defined as resolution of fever and clinical signs of infection within 120 hr following initiation of antibiotic therapy. Duration of neutropenia did not differ statistically between the two groups, and resolution of fever in all cases without complication was seen before recovery from severe neutropenia.

Results

The overall success rate was 61%. There was no statistically significant difference between the two groups: 53% for PIPC/TAZ + CAZ versus 69% for cefozopran (P = 0.122). Blood cultures were positive in eight episodes (8.4%), but there were not deaths as a result of infection.

Conclusion

Both cefozopran and PIPC/TAZ + CAZ combination therapy are safe and well tolerated in pediatric neutropenic patients. Our results show that cefozopran is a good candidate for monotherapy for neutropenic fever. Pediatr Blood Cancer 2008;51:774–777. © 2008 Wiley‐Liss, Inc.
Combined test + inhibin A at week 13 in contingent sequential testing: an interesting alternative for first‐trimester prenatal screening for Down Syndrome
Authors: Ramos‐Corpas D. J. , Santiago J. C.
Published: July 2008

Objective

To analyze various possibilities of using dimeric inhibin A (DIA) as a first‐trimester marker, during week 13, for diverse sequential strategies together with the combined test (CT) [which uses pregnancy‐associated plasma protein A, free beta‐human chorionic gonadotrophin and nuchal translucency].

Method

We analyzed three sequential strategies (nondisclosure, stepwise and contingent) for measuring DIA in week 13. Multivariate Gaussian modelling was used to estimate second‐trimester, false‐positive and detection rates. Model parameters were taken from the Serum, Urine and Ultrasound Screening Study (SURUSS) assay.

Results

The three sequential strategies provided high and comparable levels of effectiveness, with false‐positive rate for fixed detection rate of 85% and detection rate for fixed false‐positive rate of 5% values of about 91 and 2%, respectively. The contingent strategy (with two CT risk cutoffs, of 1 in 50 and 1 in 2000) produced a screening‐positive rate of 0.8% with CT, while only 23% of the women needed subsequent DIA measurement.

Conclusions

First‐trimester sequential screening using CT together with DIA measurement in week 13 is capable of producing results that are comparable with those of the integrated test, with the additional advantage that the final result is obtained earlier. It is recommended that this strategy be evaluated in large‐scale prospective studies. Copyright © 2008 John Wiley & Sons, Ltd.
Acceptance of preimplantation genetic diagnosis for β‐thalassemia in Lebanese women with previously affected children
Authors: Farra Chantal , Nassar Anwar H. , Usta Ihab M. , Salameh Pascale , Souaid Mirna , Awwad Johnny
Published: July 2008

Objective

The aim of the study was to assess the rate of acceptance of preimplantation genetic diagnosis (PGD) as an alternative to prenatal diagnosis in Lebanese women with previously affected children with homozygous β‐thalassemia.

Methods

Women with a previously affected child attending a nongovernmentally funded thalassemia care center between 1 June 2005 and 31 May 2007 were offered a genetic counseling session. This was followed by administering a questionnaire through direct interview.

Results

All 97 women approached accepted to participate in the study (100% response rate). Sixty eight per cent of women considered PGD a better alternative to prenatal diagnosis. The most important perceived advantage of PGD was the avoidance of termination of an affected pregnancy.

Conclusions

PGD is an acceptable alternative to conventional prenatal diagnosis in women at risk of conceiving a child affected with β‐thalassemia. This is particularly true in countries of the Middle‐East where therapeutic abortions for fetal indications are prohibited by the law and religion. Copyright © 2008 John Wiley & Sons, Ltd.
Properties of new nanocomposite triblock copolymer gels based on expandable graphite
Authors: Paglicawan Marissa A. , Kim Jin Kuk
Published: July 2008

In this work, we investigated the effect of expandable graphite (EG) on the property of triblock copolymer prepared from a poly(styrene‐b‐(ethylene‐co‐butylene)‐b‐styrene) (SEBS) imbibed with an EB‐compatible hydrocarbon oil. The rheological properties showed that at a temperature between 30 and 40°C below the gel point, the triblock copolymer gels had a dynamic storage modulus (G′) greater than loss modulus (G‵), thereby indicating that at ambient temperature, a physical network is still present in spite of the addition of nanoparticles. Dynamic rheological measurements of the resultant nanocomposite triblock copolymer gels confirmed that the addition of EG affects the linear viscoelastic properties and maximum operating temperature of the parent triblock copolymer gels. The mechanical properties showed only marginal increase, which can be attributed to the poor dispersion that leads to agglomeration of particle into micrometer size stacks, and thus the particles behave only as inorganic fillers. The morphology and X‐ray diffraction revealed that the EG used to generate nanocomposite triblock copolymer gels is dispersed generally within the swollen copolymer and/or solvent. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Effect of molecular weight and end capping on poly(lactic‐co‐glycolic acid) ultrasound contrast agents
Authors: Eisenbrey J.R. , Burstein O. Mualem , Wheatley M.A.
Published: July 2008

Ultrasound contrast agents (CA) consist of stabilized gas bubbles that, when injected intravenously, provide an acoustic impedance mismatch, producing additional contrast to a diagnostic ultrasound scan. These agents must be smaller than 8 μm in order to pass safely through the capillaries, contain gas for an impedance mismatch and should be stable enough to survive the duration of the imaging session. A double emulsion technique has previously been optimized within our laboratory to create CA with 50:50 poly (lactic‐co‐glycolic acid) (PLGA). Although a great deal of research has focused on the effects of molecular weight and end capping on solid PLGA particles, very little has been done to examine the effects of these parameters on hollow CAs formed in a double emulsion. Non‐end capped PLGA was found to provide maximum enhancement at a molecular weight of 66.0 kDa, giving an ultrasound enhancement of roughly 18.5 dB. The enhancement demonstrated by CA formed using the end‐capped PLGA rose to a maximum enhancement of 19 dB at the highest commercially available molecular weight of 82.4 kDa. A strong correlation was seen between ultrasound enhancement, stability under ultrasonic conditions, surface morphology and zeta potential. This study shows the influence of polymer characteristics on the resulting properties of CA and the ability to tailor CAs to particular applications by varying the polymer choice. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
In situ reactive compatibilization of aramid/polystyrene blends using amine‐functionalized polystyrene
Authors: Shabbir Saima , Zulfiqar Sonia , Ahmad Zahoor , Sarwar Muhammad Ilyas
Published: July 2008

High molecular weight aramid chains (Ar) were synthesized from aromatic diamine and diacid chloride. Amine functionality was introduced to polystyrene (PS) in two steps i.e., nitration followed by reduction producing amino functional polystyrene (APS) which serves as a reactive compatibilizer, being reactive with the Ar end‐groups. APS was characterized by FTIR, NMR spectral data, and exploited in the preparation of Ar/APS blends, and the effect of reactive compatibilization on blend morphology and interfacial adhesion was explored. Two blend systems Ar/PS and Ar/APS were investigated over a range of PS or APS ratios. To assess the effect of amine units incorporated in PS, on the compatibility with Ar; morphology, thermal, and mechanical properties were probed. Incorporation of reactivity into the system has resulted in significant refinement of the blend morphology and augmentation of thermal stability. The in situ generation of APS‐g‐Ar copolymers during solution mixing of APS and Ar was evaluated using spectroscopic analysis. In addition to stabilizing the microstructure, in situ compatibilization was found to alter the mechanical properties of the Ar/APS interface. Ar/APS blend containing 10 wt% APS was found to demonstrate optimum mechanical reinforcement as complemented by the optimal thermal and morphological profiles of 10 wt% Ar/APS blend. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Dendrimer‐like miktoarm star terpolymers: A3‐(B‐C)3 via click reaction strategy
Authors: Altintas Ozcan , Demirel A. Levent , Hizal Gurkan , Tunca Umit
Published: July 2008

Two samples of dendrimer‐like miktoarm star terpolymers: (poly(tert‐butyl acrylate))3‐(polystyrene‐poly(ε‐caprolactone))3 (PtBA)3‐(PS‐PCL)3, and (PS)3‐(PtBA‐poly(ethylene glycol)3 were prepared using efficient Cu catalyzed Huisgen cycloaddition (click reaction). As a first step, azido‐terminated 3‐arm star polymers PtBA and PS as core (A) were synthesized by atom transfer radical polymerization (ATRP) of tBA and St, respectively, followed by the conversion of bromide end group to azide. Secondly, PS‐PCL and PtBA‐PEG block copolymers with alkyne group at the junction as peripheral arms (B‐C) were obtained via multiple living polymerization mechanisms such as nitroxide mediated radical polymerization (NMP) of St, ring opening polymerization (ROP) of ε‐CL, ATRP of tBA. Thus obtained core and peripheral arms were linked via click reaction to give target (A)3‐(B‐C)3 dendrimer‐like miktoarm star terpolymers. (PtBA)3‐(PS‐PCL)3 and (PS)3‐(PEG‐PtBA)3 have been characterized by GPC, DSC, AFM, and SAXS measurements. (PtBA)3‐(PS‐PCL)3 did not show any self‐organization with annealing due to the miscibility of the peripheral arm segments. In contrast, the micro‐phase separation of the peripheral arm segments in (PS)3‐(PtBA‐PEG)3 resulted in self‐organized phase‐separated morphology with a long period of ∼ 13 nm. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 5916–5928, 2008
Emulsion and controlled miniemulsion polymerization of the renewable monomer γ‐methyl‐α‐methylene‐γ‐butyrolactone
Authors: Qi Genggeng , Nolan Michael , Schork F. Joseph , Jones Christopher W.
Published: July 2008

The kinetics of free‐radical emulsion polymerization of γ‐methyl‐α‐methylene‐γ‐butyrolactone (MeMBL), a renewable monomer related to methyl methacrylate, are presented in detail for the first time, and stable polymer latices are prepared. The effects of different reaction parameters on free‐radical emulsion polymerization of MeMBL are presented. Homogeneous nucleation is asserted to be the dominant path for particle formation. Miniemulsion copolymerization of MeMBL and styrene is also reported. In this case, the homogeneous nucleation process appears limited when using an oil soluble initiator. Both the RAFT miniemulsion polymerizations and RAFT bulk polymerizations are well controlled and narrow polydispersity copolymers are produced. Rate retardation is observed in the RAFT miniemulsion polymerizations compared with the free‐radical polymerization and RAFT bulk polymerizations and the possible causes of the retardation are discussed. The reactivity ratios of MeMBL and styrene in RAFT bulk copolymerization are also determined. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 5929–5944, 2008
Effect of Zn Powders on the Thermal Decomposition of Ammonium Perchlorate
Authors: Song Meirong , Chen Miao , Zhang Zhijun
Published: July 2008

In this paper, the catalytic effect of Zn nanopowders on thermal decomposition of ammonium perchlorate (AP) as well as those of Zn micropowders has been investigated using differential thermal analysis (DTA). The results show that both nanometer and micrometer Zn powders show similar excellent catalytic effect on the decomposition of AP, while the total heat releases of AP added by Zn nanopowders are generally higher than those of AP added by Zn micropowders. In addition, an attempt has been made to explain the observed results with the help of theoretical considerations and data generated during this work.
Isotope fractionation factors of N2O diffusion
Authors: Well Reinhard , Flessa Heinz
Published: July 2008

Isotopic signatures of N2O are increasingly used to constrain the total global flux and the relative contribution of nitrification and denitrification to N2O emissions. Interpretation of isotopic signatures of soil‐emitted N2O can be complicated by the isotopic effects of gas diffusion. The aim of our study was to measure the isotopic fractionation factors of diffusion for the isotopologues of N2O and to estimate the potential effect of diffusive fractionation during N2O fluxes from soils using simple simulations. Diffusion experiments were conducted to monitor isotopic signatures of N2O in reservoirs that lost N2O by defined diffusive fluxes. Two different mathematical approaches were used to derive diffusive isotope fractionation factors for 18O (ε18O), average 15N (εbulk) and 15N of the central (α‐) and peripheral (β‐) position within the linear N2O molecule (ε15Nα, ε15Nβ). The measured ε18O was −7.79 ± 0.27‰ and thus higher than the theoretical value of −8.7‰. Conversely, the measured εbulk (−5.23 ± 0.27‰) was lower than the theoretical value (−4.4‰). The measured site‐specific 15N fractionation factors were not equal, giving a difference between ε15Nα and ε15Nβ (εSP) of 1.55 ± 0.28‰. Diffusive fluxes of the N2O isotopologues from the soil pore space to the atmosphere were simulated, showing that isotopic signatures of N2O source pools and emitted N2O can be substantially different during periods of non‐steady state fluxes. Our results show that diffusive isotope fractionation should be taken into account when interpreting natural abundance isotopic signatures of N2O fluxes from soils. Copyright © 2008 John Wiley & Sons, Ltd.
Simultaneous determination of cyclophosphamide, ifosfamide, doxorubicin, epirubicin and daunorubicin in human urine using high‐performance liquid chromatography/electrospray ionization tandem mass spectrometry: bioanalytical method validation
Authors: Sottani Cristina , Rinaldi Paola , Leoni Emanuela , Poggi Guido , Teragni Cristina , Delmonte Angelo , Minoia Claudio
Published: July 2008

A reversed‐phase high‐performance liquid chromatography (rp‐HPLC) system interfaced with an electrospray ionization (ESI) source coupled to tandem mass spectrometry (MS/MS) was developed and validated for the determination of cyclophosphamide (CP), ifosfamide (IF), daunorubicin (DNR), doxorubicin (DXR), and epirubicin (EPI) in human urine. The analysis of samples containing multiple analytes with a dissimilar range of polarities was carried out using a conventional reversed‐phase chromatographic BDS Hypersil C8 column. The analytical run was 15 min. The triple quadrupole mass spectrometer was operated in positive ion mode and multiple reaction monitoring (MRM) was used for drug quantification. The method was validated over a concentration range of 0.2 to 4.0 µg · L−1for CP, IF, DXR, EPI and 0.15–2.0 µg · L−1for DNR in human urine. The lower limit of quantification (LLOQ) was 0.2 µg · L−1for CP, IF, EPI and was set at 0.3 and 0.15 µg · L−1for DXR and DNR, respectively. The relative standard deviations (RSD%) were <11.2% for inter‐ and intra‐day precisions. The overall accuracy was also within 114.7% for all analytes at the concentrations of the quality control samples. The potential of ionization suppression resulting from the endogenous biological material on the rp‐HPLC/MS/MS method was evaluated and measured. The feasibility of the proposed HPLC/ESI‐MS/MS procedure was demonstrated by analyzing urine samples from pharmacy technicians and nurses working in hospitals or personnel employed in drug‐manufacturing plants. Copyright © 2008 John Wiley & Sons, Ltd.
Improved imaging resolution in desorption electrospray ionization mass spectrometry
Authors: Kertesz Vilmos , Van Berkel Gary J.
Published: July 2008

The imaging resolution of desorption electrospray ionization mass spectrometry (DESI‐MS) was investigated using printed patterns on paper and thin‐layer chromatography (TLC) plate surfaces. Resolution approaching 40 µm was achieved with a typical DESI‐MS setup, which is approximately 5 times better than the best resolution reported previously. This improvement was accomplished with careful control of operational parameters (particularly spray tip‐to‐surface distance, solvent flow rate, and spacing of lane scans). In addition, an appropriately strong analyte/surface interaction and uniform surface texture on the size scale no larger than the desired imaging resolution were required to achieve this resolution. Overall, conditions providing the smallest possible effective desorption/ionization area in the DESI impact plume region and minimizing the analyte redistribution on the surface during analysis led to improved DESI‐MS imaging resolution. Published in 2008 by John Wiley & Sons, Ltd.
Performance of block‐coded land mobile satellite systems
Authors: Lee Chang‐Ming , Su Yu T.
Published: July 2008

Although various measurements have indicated that mobile satellite channels are not memoryless, most related coded system performance analysis assumes perfect interleaving is in place so that the effect of channel memory can be completely ignored. This paper presents a systematic method to accurately and efficiently predict the performance of errors‐and‐erasures or errors‐only decoders for block‐coded systems in general mobile satellite channels. Numerical results are provided to validate our analytic results. Copyright © 2008 John Wiley & Sons, Ltd.
The secondary electron emission yield for 24 solid elements excited by primary electrons in the range 250–5000 ev: a theory/experiment comparison
Authors: Walker C.G.H. , El‐Gomati M.M. , Assa'd A.M.D. , Zadražil M.
Published: July 2008

The secondary electron (SE) yield, δ, was measured from 24 different elements at low primary beam energy (250–5,000 eV). Surface contamination affects the intensity of δ but not its variation with primary electron energy. The experiments suggest that the mean free path of SEs varies across the d bands of transition metals in agreement with theory. Monte Carlo simulations suggest that surface plasmons may need to be included for improved agreement with experiment. SCANNING 30:365–380, 2008. © 2008 Wiley Periodicals, Inc.
Macroscopic Fibers of Well‐Aligned Carbon Nanotubes by Wet Spinning
Authors: Zhang Shanju , Koziol Krzysztof K. K. , Kinloch Ian A. , Windle Alan H.
Published: July 2008

A simple process to spin fibers consisting of multi‐walled carbon nanotubes (CNTs) directly from their lyotropic liquid‐crystalline phase is reported. Ethylene glycol is used as the lyotropic solvent, enabling a wider range of CNT types to be spun than previously. Fibers spun with CNTs and nitrogen‐doped CNTs are compared. X‐ray analysis reveals that nitrogen‐doped CNTs have a misalignment of only ±7.8° to the fiber axis. The tensile strength of the CNT and nitrogen‐doped CNT fibers is comparable but the modulus and electrical conductivity of the are lower. The electrical conductivity of both types of CNT fibers is found to be highly anisotropic. The results are discussed in context of the microstructure of the CNTs and fibers.
Self‐Stabilized Nanoparticles of Intrinsically Conducting Copolymers from 5‐Sulfonic‐2‐Anisidine
Authors: Li Xin‐Gui , Lü Qiu‐Feng , Huang Mei‐Rong
Published: July 2008

Novel copolymer nanoparticles with inherent self‐stability, narrow size distribution, and high electrical conductivity are facilely and productively synthesized by the oxidative precipitation polymerization of 5‐sulfonic‐2‐anisidine and aniline in acidic medium without any external stabilizer. The structures of the copolymer particles are systematically characterized by IR and UV/Vis spectroscopy, X‐ray diffraction, laser particle‐size analysis, atomic force microscopy, field‐emission scanning electron microscopy, and high‐resolution transmission electron microscopy. The comonomer ratio, oxidant/monomer ratio, and polymerization temperature and medium can be used to optimize the size and conductivity of the nanoparticles. It is found that the nanoparticles exhibit a minimal size and polydispersity index of around 53 nm and 1.045, respectively. Nanocomposite films of the nanoparticles with diacetyl and ethyl celluloses show good thermostability and a low percolation threshold of 0.08 wt%, at which the films retain 89% of the transparency, 96–98% of the strength, and 108 times the conductivity of the matrix film. The synthesis of sulfoanisidine copolymer nanoparticles is thus achieved without the use of external stabilizer, which opens up a simple and general route to the fabrication of nanostructured polymer materials with controllable size, narrow size distribution, intrinsic self‐stability, strong dispersibility, high purity, and optimizable electroconductivity.
ROI of software process improvement at BL informática: SPIdex is really worth it
Authors: Ferreiro Ferreira Analia Irigoyen , Santos Gleison , Cerqueira Roberta , Montoni Mariano , Barreto Ahilton , Rocha Ana Regina , Barreto Andrea O. S. , Silva Filho Reinaldo C.
Published: July 2008

In today's global competitive environment, organizations are always trying to improve their practices aiming to achieve higher levels of productivity, quality and competitiveness. Software process improvement (SPIdex) is one of the most used approaches to achieve these goals. However, this kind of initiative is not easy, and usually great investments are necessary. Therefore, determining the return on these investments is very important to justify them and keep high‐level management and project teams motivated for continuous improvement. In this article, we present quantitative results of return on investment (ROI) at BL Informática, a Brazilian small‐sized organization which is improving its processes since 2003 and is experiencing great success. We present the benefits regarding schedule, costs, productivity, quality, customer satisfaction and also financial benefits. Results show that investments in SPIdex really can pay off, as happened at BL Informática. Copyright © 2008 John Wiley & Sons, Ltd.
Human resources based improvement strategies—the learning factor
Authors: Messnarz Richard , Ekert Damjan , Reiner Michael , O'Suilleabhain Gearoid
Published: July 2008

Processes usually are defined according to the underlying standards (ISO 15504, ESA ECSS, ISO 9001, etc.) and are described with process steps to be performed by roles and producing results (outputs) from well‐defined inputs, methods and tools to support the process steps, and activities to be done and skills to be covered by roles (Messnarz Ret et al. Proceedings of the 6th European Conference on Quality Assurance, Vienna 10–12 April 1999). Assessments and the resulting improvement initiatives focus much on the processes and less on the human resources based strategies.

In this article we want to emphasise that both issues are of equal importance, the processes and the highly skilled human force. We also highlight a currently running European strategy (European Qualification Network (EQN)) and a funded technology project PLATO which support the establishment of such a human resource and learning strategy in Europe. Copyright © 2008 John Wiley & Sons, Ltd.
Using virtual reality for evaluation of fetal ambiguous genitalia
Authors: Verwoerd‐Dikkeboom C. M. , Koning A. H. J. , Groenenberg I. A. L. , Smit B. J. , Brezinka C. , Van Der Spek P. J. , Steegers E. A. P.
Published: July 2008

Objective

The utility of a virtual reality system was examined in the visualization of three‐dimensional (3D) ultrasound images of fetal ambiguous genitalia.

Methods

In 2005, fetal ambiguous genitalia were diagnosed in four patients referred to our department for prenatal ultrasound assessment. The patients were examined by two‐dimensional (2D) and 3D ultrasound and, subsequently, the volumes obtained on 3D ultrasound were visualized in the BARCO I‐Space virtual reality system. This system projects stereoscopic images on three walls and the floor of a small ‘room’, allowing several viewers to see a 3D ‘hologram’ of the data being visualized. The results of 2D and 3D ultrasound examination and the virtual reality images of the I‐Space were compared with diagnoses made postpartum.

Results

In all cases, prenatal diagnosis was unclear based on 2D ultrasound alone. Surface rendering of 3D data provided an impression of ambiguity, but diagnosis based on these data proved incorrect at birth in three cases. Conclusions based on the evaluation of 3D volumes in virtual reality best fitted the postpartum diagnosis in all cases.

Conclusions

This study suggests that by evaluation of the genitals in the I‐Space, a better impression of genital ambiguity can be established. Binocular depth perception appeared particularly useful in distinguishing either a micropenis or enlarged clitoris from labia minora, since it helps in the estimation of size and position. Therefore, we see potential for the application of virtual reality not only for the evaluation of fetal ambiguous genitalia, but in all those cases where depth perception would improve the visualization of anatomical structures. Copyright © 2008 ISUOG. Published by John Wiley & Sons, Ltd.
Thickness of fetal membranes: a possible ultrasound marker for preterm delivery
Authors: Severi F. M. , Bocchi C. , Voltolini C. , Borges L. E. , Florio P. , Petraglia F.
Published: July 2008

Objective

To evaluate whether measurement of the thickness of the fetal membranes by high‐resolution ultrasound is a useful marker to predict preterm delivery.

Methods

One hundred and fifty‐eight women with singleton pregnancies at 18–35 gestational weeks were enrolled consecutively at our referral center for obstetric care and the thickness of their fetal membranes was measured using high‐resolution ultrasound equipment. Data were analyzed to determine whether there were significant differences between those delivering at term and those delivering preterm. Receiver–operating characteristics (ROC) curves were used to determine the best cut‐off point of membrane thickness for predicting preterm birth.

Results

Women who delivered preterm had greater fetal membrane thickness than did those who delivered at term (1.67 ± 0.27 mm vs. 1.14 ± 0.30 mm, P < 0.0001). For the best cut‐off indicated by ROC curve analysis (1.2 mm), the sensitivity and specificity for predicting preterm birth were 100% (95% CI, 80.3–100) and 69.5% (95% CI, 61.2–77.0), respectively, and positive and negative likelihood ratios were 3.3 and 0.0, respectively.

Conclusion

Sonographic measurement of fetal membrane thickness could be helpful in the prediction of preterm delivery. Copyright © 2008 ISUOG. Published by John Wiley & Sons, Ltd.
Performance analysis of transmitted‐reference UWB systems with narrowband interference suppression
Authors: Cui S. , Teh K. C. , Li K. H. , Guan Y. L. , Law C. L.
Published: July 2008

In this paper, we propose a receiver structure for transmitted‐reference ultra‐wideband (TR‐‐UWB) systems with both narrowband interference (NBI) and inter‐pulse interference (IPI) mitigation capabilities. The effects of additive white Gaussian noise (AWGN) and the IEEE 802.15.4a fading channel are also taken into consideration. We adopt band‐stop filtering to suppress the NBI. For IPI, it is statistically removed by a sum‐and‐average process. Theoretical analysis is carried out to study the lower bound of the bit‐error rate (BER) performance of the proposed receiver. Numerical results show that the proposed receiver is able to provide satisfactory performance and is robust to variations in the system design parameters. It is also observed that the proposed receiver is able to deliver good performance even when there is zero delay between the reference and data pulses, which can effectively double the system throughput. Copyright © 2008 John Wiley & Sons, Ltd.