bluuebunny/crossref_metadata_2025 huggingface dataset:
Near‐Field Lithography by Two‐Photon Induced Photocleavage of Organic Monolayers
Authors: Álvarez Marta , Best Andreas , Unger Andreas , Alonso José M. , del Campo Aránzazu , Schmelzeisen Marcus , Koynov Kaloian , Kreiter Max
Published: October 2010

We prove that the enhanced electromagnetic near‐field around metallic nanostructures can be used for localized two‐photon induced activation of surfaces, obtaining a defined chemical pattern with nanometric resolution. Gold nanoparticles (Au‐NP) are deposited on glass slides that were modified with a polysiloxane layer containing a nitroveratrylcarbonyl (NVoc) photoremovable group. Upon illumination with a femtosecond laser, the NVoc entity is removed. Due to the electromagnetic field enhancement of the nanoparticles, the threshold of this process is lowered in the nm‐scale vicinity of the metal structures. Upon cleavage, an amine functional group is released, which can be used to site‐selectively bind species with complementary chemical functionality on the surface. This method can be utilized for sub‐wavelength chemical structuring.
Homogeneous and Disordered Assembly of Densely Packed Nanocrystals
Authors: Oaki Yuya , Anzai Takeo , Imai Hiroaki
Published: October 2010

A homogeneous and disordered assembly of densely packed nanocrystals is generated without the assistance of organic molecules, from an aqueous solution at room temperature. The densely packed nanocrystals of tin dioxide (SnO2) and titanium dioxide (TiO2), 2–3 nm in size, form glassy macroscopic transparent objects of 2–10 mm. The monodisperse nanocrystals, which have a surface hydrated layer and are synthesized in aqueous solution, are densely packed in an homogeneous and disordered assembly through the evaporation of water as the dispersion medium. The formation of transparent bulk objects on the macroscopic scale originates from the homogeneous and disordered nature of the densely packed nanocrystals. The resultant homogeneous architectures are distinguishable from the typical inhomogeneous and disordered aggregates of nanoparticles observed after evaporation of the dispersion medium. Among superstructures based on nanocrystals, such as superlattices and mesocrystals, the resultant homogeneous and disordered assembly can be regarded as a new class of solid‐state material.
CO2 reduction with Zn particles in a packed‐bed reactor
Authors: Loutzenhiser Peter G. , Barthel Frank , Stamatiou Anastasia , Steinfeld Aldo
Published: October 2010

A two‐step solar thermochemical cycle for splitting CO2 with Zn/ZnO redox reactions is considered, consisting of: (1) the endothermic dissociation of ZnO with concentrated solar radiation as the heat source and (2) the non‐solar, exothermic, reduction of CO2 to CO by oxidizing Zn to ZnO; the latter is recycled to the first step. The second step of the cycle is investigated using a packed‐bed reactor where micron‐sized Zn particles were immobilized in mixtures with submicron‐sized ZnO particles. Experimental runs were performed for Zn mass fractions in the range 67–100 wt % and CO2 concentration in the range 25–100%, yielding Zn‐to‐ZnO conversions up to 71% because of sintering prevention, as corroborated by SEM analysis. © 2010 American Institute of Chemical Engineers AIChE J, 2011
Studies on electrochemical treatment of dairy wastewater using aluminum electrode
Authors: Prakash Kushwaha Jai , Chandra Srivastava Vimal , Deo Mall Indra
Published: October 2010

This study reports results of electrochemical treatment to the synthetic dairy wastewater using aluminum electrode. Response surface methodology with four factors and five level full factorial central composite design has been used to design the experiments. Four operational parameters, namely current density (J): 61.73–308.64 A/m2; dosage of sodium chloride (NaCl) (m): 0–2 g/l; electrolysis time (t): 10–90 min and initial pH (pHo): 5–11, have been taken as input parameters and percentage chemical oxygen demand (COD) removal (Y1) and the specific energy consumed (kWh per Kg of COD removed, Y2) have been taken as responses of the system. Multiresponse optimization technique has been applied to find values of operational parameters which maximize the Y1 and simultaneously minimize Y2. The optimum values of operational parameters were found to be J = 123.46 A/m2, m = 2.0 g/l, t = 74 min, and pHo = 6.5. Optimum Y1 and Y2 were found to be 70.91% and 1.32 kWh/kg COD removed. © 2010 American Institute of Chemical Engineers AIChE J, 2011
β‐Cyclodextrin inclusive interaction driven separation of organic compounds
Authors: Ji H. B. , Long Q. P. , Chen H. Y. , Zhou X. T. , Hu X. F.
Published: October 2010

A novel selective separation method for organic compounds, especially thermosensitive substances, has been proposed using unsubstituted β‐cyclodextrin (β‐CD) as a host and some alcohols and aldehydes as model guests in aqueous solution. The separation factors were evaluated from the extraction of an equimolar mixture of alcohol and aldehyde compounds. The inclusion equilibrium constants for several alcohols and aldehydes over β‐CD have been calculated through their UV‐vis spectra. The Gibbs free energy changes of β‐CD/substrates complexes (ΔG) have been calculated combined B3LYP/6‐31G(d)//ONIOM2(B3LYP/6‐31G(d):PM3) with semicontinuum solvation model. The difference of Gibbs free energy changes (ΔΔG) for the inclusion complexes formed via the intermolecular weak interactions e.g., hydrogen bond and electrostatic interaction was the reason why alcohol and aldehyde compounds could be selectively separated. © 2010 American Institute of Chemical Engineers AIChE J, 2011
Phenotypic variability of a deletion and duplication 6q16.1 → q21 due to a paternal balanced ins(7;6)(p15;q16.1q21)
Authors: Spreiz Ana , Müller Doris , Zotter Sibylle , Albrecht Ursula , Baumann Matthias , Fauth Christine , Erdel Martin , Zschocke Johannes , Utermann Gerd , Kotzot Dieter
Published: October 2010

Constitutional insertional translocations are rare findings in clinical cytogenetics. Here, we report on the unbalanced segregation of a balanced paternal insertional translocation ins(7;6)(p15;q16.1q21) to three children. Investigations by conventional karyotyping, FISH with locus‐specific probes, microsatellite marker analysis, and SNP‐array based copy number analysis revealed a direct orientation of the inserted segment, a size of 11.3 Mb, and breakpoints between rs4370337 and rs12660854 and rs12110990 and rs4946730 on 6q16.1 and 6q21, respectively, as well as within BAC clone RP11–182J2 on 7p15. A 17‐year‐old daughter inherited the der(6) chromosome and was affected by severe mental retardation, obesity, and minor anomalies. Two further children inherited the der(7) chromosome. A daughter shows an almost unremarkable phenotype and only minor features in neuropsychological testing at 19 years of age. Her 14‐year‐old half‐brother demonstrates a mild delay in cognitive development most likely jointly caused by the chromosomal rearrangement and asphyxia during delivery. The patient with the deletion confirms the previously reported phenotype of severe mental retardation and obesity in patients with del(6)(q16.2), while both patients with partial trisomy for the same segment of chromosome 6 are further examples for a generally less severe phenotype associated with duplications than with deletions, and even for the recent insight that chromosomal aneusomies of several megabases may go without major clinical consequences. © 2010 Wiley‐Liss, Inc.
A dimethylzinc/diphenylphosphinoylimine approach to the asymmetric synthesis of the calcimimetic agent NPS R‐568
Authors: Banerjee Sucharita , Smith Brad , Hitchcock Shawn R.
Published: October 2010

An asymmetric synthesis of the calcimimetic agent NPS R‐568 using a (1R,2S)‐N‐benzylephedrine‐promoted addition of dimethylzinc to a diphenylphosphinoylimine derived from 3‐methoxybenzaldehyde is described. The enantiomeric ratio of the key amine fragment was determined to be 93:7 (86% ee), favoring the (R)‐enantiomer by derivatization and chiral stationary phase HPLC analysis. Copyright © 2010 John Wiley & Sons, Ltd.
Effect of chemical structure of silane coupling agent on interface adhesion properties of syndiotactic polypropylene/cellulose composite
Authors: Nakatani Hisayuki , Iwakura Keisuke , Miyazaki Kensuke , Okazaki Noriyasu , Terano Minoru
Published: October 2010

To improve interaction between syndiotactic polypropylene (SPP) and fibrous cellulose (FC), effects of chemical structure of silane coupling agent on the reactivity for the surface hydroxyl group on the FC were studied by X‐ray photoelectron spectroscopy (XPS) measurement. Among the three kinds of the silane coupling agent, the 3‐aminopropyltrimethoxysilane (APTMS) showed the highest reactivity with the surface hydroxyl group on the FC, and the linear silane compound with methoxyl group was found to be suitable for the reaction. Although the morphology of the SPP/FC composite is hardly affected by the difference in the kinds of the silane coupling agent, the tensile properties were considerably different. In particular, in the case of using higher silane coupling agent solution (over 3 wt %), the chemical structure of silane coupling agent certainly affected the tensile properties of the SPP/silanized FC composite. It was found that the tensile properties were distinctly affected by the reactivity between the surface hydroxyl group on FC and the silane coupling agent. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Structure and physical properties in crosslinked polyurethanes
Authors: Waterlot Véronique , Couturier Daniel , Waterlot Christophe
Published: October 2010

Crosslinked polyurethanes based on a mixture of toluene diisocyanate, polypropylene glycol, trimethylol propane (TMP), glycerol (GLY), and desmophen (DES) were synthesized with various ratios of DES and GLY. Chemical crosslinks were introduced through the hard segment (TMP, GLY) and through the soft segment (DES). The effects of the degree of crosslinking on the properties were examined. The crystallinity of the obtained polymers were studied by using modulated differential scanning calorimetry, differential scanning calorimetry, dynamic mechanical analysis and their morphology was studied by atomic force microscopy. It appeared that the degree of crosslinking increased according to the increase of GLY content. Moreover, it was found that chemical crosslinks in the hard segment destroyed the crystallinity of the hard phase and reduced the mobility of the soft phase, improving the heat stability of the hard domains, and modifying the mechanical properties of polyurethane films. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
The effect of genotype on methotrexate polyglutamate variability in juvenile idiopathic arthritis and association with drug response
Authors: Becker Mara L. , Gaedigk Roger , van Haandel Leon , Thomas Bradley , Lasky Andrew , Hoeltzel Mark , Dai Hongying , Stobaugh John , Leeder J. Steven
Published: October 2010

Objective

The response to and toxicity of methotrexate (MTX) are unpredictable in patients with juvenile idiopathic arthritis (JIA). Intracellular polyglutamation of MTX, assessed by measuring concentrations of MTX polyglutamates (MTXGlu), has been demonstrated to be a promising predictor of drug response. Therefore, this study was aimed at investigating the genetic predictors of MTXGlu variability and associations between MTXGlu and drug response in JIA.

Methods

The study was designed as a single‐center cross‐sectional analysis of patients with JIA who were receiving stable doses of MTX at a tertiary care children's hospital. After informed consent was obtained from the 104 patients with JIA, blood was withdrawn during routine MTX‐screening laboratory testing. Clinical data were collected by chart review. Genotyping for 34 single‐nucleotide polymorphisms (SNPs) in 18 genes within the MTX metabolic pathway was performed. An ion‐pair chromatographic procedure with mass spectrometric detection was used to measure MTXGlu1–7.

Results

Analysis and genotyping of MTXGlu was completed in the 104 patients. K‐means clustering resulted in 3 distinct patterns of MTX polyglutamation. Cluster 1 had low red blood cell (RBC) MTXGlu concentrations, cluster 2 had moderately high RBC MTXGlu1 + 2 concentrations, and cluster 3 had high concentrations of MTXGlu, specifically MTXGlu3–5. SNPs in the purine and pyrimidine synthesis pathways, as well as the adenosine pathway, were significantly associated with cluster subtype. The cluster with high concentrations of MTXGlu3–5 was associated with elevated liver enzyme levels on liver function tests (LFTs), and there were higher concentrations of MTXGlu3–5 in children who reported gastrointestinal side effects and had abnormal findings on LFTs. No association was noted between MTXGlu and active arthritis.

Conclusion

MTXGlu remains a potentially useful tool for determining outcomes in patients with JIA being treated with MTX. The genetic predictors of MTXGlu variability may also contribute to a better understanding of the intracellular biotransformation of MTX in these patients.
Immune complexes containing citrullinated fibrinogen costimulate macrophages via Toll‐like receptor 4 and Fcγ receptor
Authors: Sokolove Jeremy , Zhao Xiaoyan , Chandra Piyanka E. , Robinson William H.
Published: October 2010

Objective

Rheumatoid arthritis (RA) is associated with the presence of anti–citrullinated protein antibodies (ACPAs). Nearly two‐thirds of patients with ACPA‐positive RA have immune complexes that contain citrullinated fibrinogen, and these citrullinated fibrinogen–containing immune complexes (cFb‐IC) can exacerbate disease in murine models of RA; however, the exact role of such ACPA ICs in RA pathogenesis has remained elusive. We undertook the present study to investigate a novel mechanism by which ACPAs specifically targeting citrullinated fibrinogen may directly stimulate macrophage tumor necrosis factor (TNF) production.

Methods

Murine or human macrophages were stimulated with native fibrinogen (nFb), cFb, or in vitro–generated nFb‐IC or cFb‐IC, and TNF production was measured by enzyme‐linked immunosorbent assay. ICs were generated with either polyclonal anti‐Fb antibodies or pooled IgG from patients with ACPA‐positive RA. To evaluate the role of the Toll‐like receptor 4 (TLR‐4)/myeloid differentiation protein (MyD88) pathway and the Fcγ receptor (FcγR) pathway in the induction of TNF by Fb and Fb‐IC, parallel experiments were performed using 1) TLR‐4–deficient or MyD88‐deficient macrophages, and 2) inhibitors of TLR‐4 or FcγR.

Results

Citrullinated Fb stimulated macrophage TNF production more potently than did native Fb. Incorporation of cFb into ICs augmented its ability to stimulate TNF production by macrophages. Stimulation of TNF by cFb was dependent on TLR‐4 and MyD88, while stimulation by cFb‐IC was dependent on both TLR‐4/MyD88 and FcγR.

Conclusion

We demonstrated that cFb‐IC can costimulate macrophages via dual engagement of TLR‐4 and FcγR, resulting in the synergistic induction of TNF production. Our findings suggest a potential role of citrullination in increasing the potency of an endogenous innate immune ligand and provide insight into the mechanism by which anticitrulline autoimmunity may contribute to the onset and propagation of inflammation in RA.
Systemic lupus erythematosus monocytes are less responsive to interleukin‐10 in the presence of immune complexes
Authors: Yuan Weijia , DiMartino Stephen J. , Redecha Patricia B. , Ivashkiv Lionel B. , Salmon Jane E.
Published: October 2010

Objective

Systemic lupus erythematosus (SLE) is a systemic inflammatory disease characterized by autoantibody production and immune complex deposition. The level of interleukin‐10 (IL‐10), predominantly an antiinflammatory cytokine, is paradoxically elevated in patients with SLE. The aim of this study was to examine the hypothesis that the antiinflammatory function of IL‐10 is impaired in monocytes from patients with SLE with long‐term exposure to immune complexes.

Methods

CD14+ monocytes were isolated from healthy donors and patients with SLE. Cultured CD14+ cells were treated with heat‐aggregated human IgG (325 μg/ml) in the presence or absence of IL‐10 (20 ng/ml). To study gene expression, RNA was extracted 3 hours after treatment. To study cytokine production, supernatants were harvested after 8 hours. To study IL‐10 signaling, cell lysates were obtained from CD14+ cells treated with human IgG (325 μg/ml) for 1 hour followed by IL‐10 (20 ng/ml) treatment for 10 minutes. Western blot analysis was used to assess STAT‐3 phosphorylation. All experiments were performed in pairs.

Results

When stimulated with human IgG, SLE monocytes produced more tumor necrosis factor α (TNFα) and IL‐6 than did control cells. The suppressive effect of IL‐10 on human IgG–induced TNFα and IL‐6 production was lower in SLE monocytes compared with control monocytes, although IL‐10 receptor expression was similar in SLE and control monocytes. Human IgG suppressed IL‐10 receptor expression and altered IL‐10 signaling in control monocytes. Like SLE monocytes, interferon‐α (IFNα)–primed control monocytes stimulated with human IgG were also less responsive to IL‐10.

Conclusion

Human IgG and IFNα modulate IL‐10 function. In SLE monocytes, which are considered to be IFNα primed and persistently exposed to immune complexes, responses to IL‐10 are abnormal, limiting the antiinflammatory effect of this cytokine.
Pattern on the antinuclear antibody–HEp‐2 test is a critical parameter for discriminating antinuclear antibody–positive healthy individuals and patients with autoimmune rheumatic diseases
Authors: Mariz Henrique A. , Sato Emília I. , Barbosa Silvia H. , Rodrigues Silvia H. , Dellavance Alessandra , Andrade Luis E. C.
Published: October 2010

Objective

To identify features of antinuclear antibody (ANA)–HEp‐2 test results that discriminate ANA‐positive healthy individuals and patients with autoimmune rheumatic diseases (ARDs).

Methods

We sequentially retrieved data on 918 healthy individuals and 153 patients with ARDs after clinical assessment. ANA‐positive healthy individuals for whom data were available were reevaluated after 3.6–5.0 years. An ANA–HEp‐2 test result was considered positive when a clear ANA pattern was observed at 1:80 dilution in 2 distinct commercial HEp‐2 slides by 2 blinded independent observers.

Results

ANAs were present in 118 healthy individuals (12.9%) and 138 patients with ARDs (90.2%). The ANA titer was higher in patients with ARDs than in healthy individuals (P < 0.001). The ANA pattern profile was distinct in the 2 groups. Nuclear homogeneous, nuclear coarse speckled, and nuclear centromeric patterns appeared exclusively in patients with ARDs. The nuclear dense fine speckled pattern occurred only in healthy individuals. The most frequent ANA pattern in both groups was the nuclear fine speckled pattern, which occurred at lower titer in healthy individuals than in patients with ARDs (P < 0.001). Anti–extractable nuclear antigen was present in 1 healthy individual (anti‐SSA/Ro) and in 52 patients with ARDs (37.7%). None of the 40 reevaluated healthy individuals developed ARDs, and 29 (72.5%) remained ANA positive. All healthy individuals who became ANA negative had an ANA titer of 1:80 at baseline.

Conclusion

Our findings suggest that the titer, and especially the pattern, on the ANA–HEp‐2 test strongly enhances our ability to discriminate ANA‐positive healthy individuals and patients with ARDs.
Interferon‐α accelerates murine systemic lupus erythematosus in a T cell–dependent manner
Authors: Liu Zheng , Bethunaickan Ramalingam , Huang Weiqing , Lodhi Umairullah , Solano Ingrid , Madaio Michael P. , Davidson Anne
Published: October 2010

Objective

To investigate the mechanism by which interferon‐α (IFNα) accelerates systemic lupus erythematosus (SLE) in (NZB × NZW)F1 (NZB/NZW) mice.

Methods

NZB/NZW mice were treated with an adenovirus expressing IFNα. In some mice, T cells were depleted with an anti‐CD4 antibody. The production of anti–double‐stranded DNA (anti‐dsDNA) antibodies was measured by enzyme‐linked immunosorbent assay and enzyme‐linked immunospot assay. Germinal centers and antibody‐secreting cells (ASCs) in spleens and IgG deposition and leukocyte infiltrates in kidneys were visualized by immunofluorescence staining. The phenotype of splenic cells was determined by flow cytometry. Finally, somatic hypermutation and gene usage in VH regions of IgG2a and IgG3 were studied by single‐cell polymerase chain reaction.

Results

IFNα‐accelerated lupus in NZB/NZW mice was associated with elevated serum levels of IgG2 and IgG3 anti‐dsDNA antibodies and accumulation of many IgG ASCs in the spleen, which did not develop into long‐lived plasma cells. Furthermore, IgG2a and IgG3 antibodies in the mice were highly somatically mutated and used distinct repertoires of VH genes. The induction of SLE in the mice was associated with an increase in B cell Toll‐like receptor 7 expression, increased serum levels of BAFF, interleukin‐6 (IL‐6), and tumor necrosis factor α, and induction of T cells expressing IL‐21. Although IFNα drove a T cell–independent increase in serum levels of IgG, autoantibody induction and the development of nephritis were both completely dependent on CD4+ T cell help.

Conclusion

These findings demonstrate that, although IFNα activates both innate and adaptive immune responses in NZB/NZW mice, CD4+ T cells are necessary for IFNα‐driven induction of anti‐dsDNA antibodies and clinical SLE.
Evaluation of a lecture recording system in a medical curriculum
Authors: Bacro Thierry R.H. , Gebregziabher Mulugeta , Fitzharris Timothy P.
Published: October 2010

Recently, the Medical University of South Carolina adopted a lecture recording system (LRS). A retrospective study of LRS was implemented to document the students' perceptions, pattern of usage, and impact on the students' grades in three basic sciences courses (Cell Biology/Histology, Physiology, and Neurosciences). The number of accesses and length of viewings of the recordings were recorded per week for each student and correlated with the grades in each of the three courses. Attendance records were not available. The results showed considerable variability in the use of the LRS by both faculty and students during the entire semester and across all three courses, including week to week variations. Data indicated that 30% of the students did not use the LRS at all with 41% of the students using it very little (less than 10 times for a total of 131 recordings). Specific patterns of usage were identified for each of the three courses throughout the semester, with an increase in access prior or during examination weeks. However, the statistical analysis showed that there was no correlation between the final grades and the usage of LRS. Finally, a survey of the students' perception showed that 74% agreed/strongly agreed that the recordings were useful with 6% disagreeing/strongly disagreeing and 11% undecided. This study showed that the use of LRS might be a viable alternative for students unable to attend lecture due to circumstances such as illness but that more research is needed to truly understand the best pedagogical use of LRS. Anat Sci Educ. © 2010 American Association of Anatomists.
A systemic view of biodiversity and its conservation: Processes, interrelationships, and human culture
Authors: Sterling Eleanor J. , Gómez Andrés , Porzecanski Ana L.
Published: October 2010

Historically, views and measurements of biodiversity have had a narrow focus, for instance, characterizing the attributes of observable patterns but affording less attention to processes. Here, we explore the question: how does a systems thinking view – one where the world is seen as elements and processes that connect and interact in dynamic ways to form a whole – affect the way we understand biodiversity and practice conservation? We answer this question by illustrating the systemic properties of biodiversity at multiple levels, and show that biodiversity is a collection of dynamic systems linking seemingly disparate biological and cultural components and requiring an understanding of the system as a whole. We conclude that systems thinking calls traditional views of species, ecosystem function, and human relationships with the rest of biodiversity into question. Finally, we suggest some of the ways in which this view can impact the science and practice of conservation, particularly through affecting our conservation targets and strategies.
Morphology and Microstructure of Li/MgO Catalysts for the Oxidative Coupling of Methane
Authors: Zavyalova Ulyana , Geske Michael , Horn Raimund , Weinberg Gisela , Frandsen Wiebke , Schuster Manfred , Schlögl Robert
Published: October 2010

A series of catalysts for the oxidative coupling of methane (OCM) based on MgO with a varying content of Li have been synthesized by the gel‐combustion method. The resulting catalytically active systems are studied by a combination of TEM and SEM methods. Samples with a low abundance of Li exhibit a hierarchical pore system built from tubular structures made from primary MgO particles. Upon calcination at 1073 K, these particles undergo a change in shape from cubic via truncated octahedral to platelet morphologies, depending on the Li content of the precursor. Morphological indications have been found for the role of Li as flux in this transformation. The modification of the primary particle morphology leads to a drastic change in secondary structure from open sponges to compact sintered plates upon addition of Li at loadings above 10 wt %, with respect to the precursor. The microstructure of the primary particles reveals two families of high‐energy structures, namely edge‐and‐step structures and protrusions on flat terraces. A relation was found between catalytic function in OCM and the transformation from cubic to complex‐ terminated particles. Based on these findings, it is suggested that sites active for the coupling reaction of methane are related to the protrusions arising from segregation of oxygen vacancies to the surface of MgO.
Recycling Concept for Aluminum Electrodeposition from the Ionic Liquid System EMIM[Tf2N]‐AlCl3
Authors: Solà Cervera J. L. , König A.
Published: October 2010

In the last years, the ionic liquid system formed by specific mixtures of 1‐ethyl‐3‐methylimidazolium bis[(trifluoromethyl)sulfonyl]imide (EMIM[Tf2N]) and AlCl3 proved to be a very suitable electrolyte for the electrodeposition of aluminum. In order to establish an industrial electrodeposition process based on this novel electrolyte system, the suitability of melt crystallization for purification and recycling of these electrolytes has been studied. It exists a composition range in the ternary system where the compound EMIM[AlCl4] can be crystallized in a high purity. The layer melt crystallization technique is successfully applied to the binary system EMIMCl‐AlCl3 and to the real ternary electrolytes. Hydrolysis is proposed for treatment of the residue. In aqueous solutions, the membrane process nanofiltration is applied for concentration and recovery of the ionic components. An integral recycling concept is presented.
Effect of annealing on the mechanical behaviour of Au/Cu and Cu/Au bilayers on silicon
Authors: Chocyk D. , Prószyński A. , Gladyszewski G.
Published: October 2010

The realtime evolution of stress during deposition of Cu/Au and Au/Cu bilayers was studied by an in‐situ curvature measurement optical technique and annealing in the temperature range from room temperature to 400 °C. The Au/Cu and Cu/Au bilayers attached to silicon substrate with total thickness equal 12 nm and individual film thicknesses equal 6 nm Cu and 6 nm Au; 4 nm Cu and 8 nm Au; and 8 nm Cu and 4 nm Au, respectively, were examined. During deposition, an increase in tensile stress with increasing the total thickness of a system for both Au/Cu and Cu/Au bilayers were observed. Deposition of Au layer on Cu layer resulted in a change in compressive direction, whereas no change was observed for Cu deposition on Au. This difference is explained by lattice parameter mismatch. Significant stress evolution during the first cycle of heating was observed for all samples. It was found that irreversible modifications occur in systems during the first cycle of annealing. A change in the slope of the elastic part of stress curve during heating indicates a change in the coefficient of thermal expansion of metallic layers. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electronic structure of Prx La1‐xAlO3 solid solution
Authors: Szubka M. , Talik E. , Molak A. , Turczyński S. , Pawlak D. A.
Published: October 2010

The crystals of Prx La1−xAlO3 solid solution grown by the Czochralski method were examined by X‐ray photoelectron spectroscopy. The electric conductivity was measured at high temperature range. The composition of the Prx La1−xAlO3+xcrystals obtained with XPS analysis exhibited an increased content of oxygen in comparison to the nominal value. The praseodymium valence may influence the coloration of the Prx La1−xAlO3 crystals. In the dark brown colour Pr0.40La0.60AlO3 sample with the highest amount of oxygen the 3d4f1 satellite lines have the highest intensity and were attributed to presence of Pr4+ ions. The semiconducting properties of the Prx La1−xAlO3 single crystals correspond to the electronic structure determined with the XPS measurements and to the deduced occurrence of defects. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Single crystal growth and structural properties of iron telluride doped with nickel
Authors: Zajdel P. , Zubko M. , Kusz J. , Green M. A.
Published: October 2010

We report the single crystal growth of Fe1.1−xNix Te with nominal compositions x = 0.01, 0.025, 0.05 and 0.1 using a slow cooled melt technique. Cylindrical crystals 0.5 cm in diameter and 2 cm long were obtained. The initial characterization, done using single‐crystal diffractometer, revealed that the lattice parameter a increases and c decreases with Ni content. The crystal structure refinement was performed in the P4/nmm space group. Chemical analysis confirmed the presence of nickel in the system close to the nominal content. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Micropower high current‐drive class AB CMOS current‐feedback operational amplifier
Authors: Lopez‐Martin Antonio J. , Ramirez‐Angulo Jaime , Carvajal Ramón G. , Acosta Lucía
Published: October 2010

A novel CMOS current‐feedback operational amplifier (CFOA) aimed to low‐power applications is proposed. The use of a compact class AB implementation allows high current‐drive capability and simultaneously very low quiescent power consumption. Measurement results of a fabricated prototype show for an inverting configuration a closed‐loop bandwidth of 1 MHz independent of gain setting, and a slew rate of 2V/µs for a load capacitance of 30 pF and a quiescent power consumption of 264µW. Copyright © 2010 John Wiley & Sons, Ltd.
A CMOS voltage regulator for passive RFID tag ICs
Authors: Guo Jianping , Leung Ka Nang
Published: October 2010

A low‐power voltage regulator for passive RFID tag ICs is proposed in this paper. It consists of a self‐biased mutually compensated voltage reference, a low dropout (LDO) voltage regulation circuit and a power‐on‐reset (POR) circuit. It is fabricated in a commercial 0.18−µm CMOS technology and applied to a passive UHF RFID tag IC. The total quiescent current is 700 nA under a 1.8‐V supply. The output voltage of the regulator is 1.45 V with load capability of 50 µA. The temperature coefficients of the voltage reference and the output voltage are only 9 and 43 ppm/∘C, respectively. A POR signal with width pulse of 150 ns is generated for the digital part in the tag IC. Copyright © 2010 John Wiley & Sons, Ltd.
Robust model order reduction technique for MIMO systems via ANN‐LMI‐based state residualization
Authors: Alsmadi Othman M. K. , Abo‐Hammour Zaer. S. , Al‐Smadi Adnan M.
Published: October 2010

Even though model order reduction (MOR) techniques for linear dynamical systems are developed rather properly, there are still quite a lot of issues to be considered. This paper addresses a novel MOR technique for multi‐input multi‐output system with dominant eigenvalue preservation, which leads to controller cost minimization. The new technique is formulated based on an artificial neural network (ANN) prediction of an upper triangular form of the system state matrix A. Using the new system state matrix along with the linear matrix inequality (LMI) optimization method, a permutation matrix is obtained which leads to the new formulation of the complete system considered for MOR. Utilizing the non‐projection state residualization technique, a reduced model order is obtained. The proposed ANN‐LMI‐based MOR method is compared with well‐known reduction techniques such as the balanced Schur decomposition, proper orthogonal decomposition (POD), and state elimination through balanced realization. Copyright © 2010 John Wiley & Sons, Ltd.
Phase noise characterization of subharmonic injection locked oscillators
Authors: Plessas Fotis , Tsitouras Athanasios , Kalivas Grigorios
Published: October 2010

In this work we present a detailed study of the phase noise of subharmonic injection locked oscillators (s‐ILOs). A new simple and efficient model has been presented for accurately predicting the phase noise of a microwave s‐ILO. The validity of the analytical technique is verified with measurement results obtained from a 5‐GHz fully differential Colpitts‐based s‐ILO. The results showed that a phase noise improvement of 12 dB at 1 kHz offset frequency compared to the free‐running case can be achieved, whereas the power consumption is 21 mW. Copyright © 2010 John Wiley & Sons, Ltd.
A study design with conditional, serially assessed co‐primary endpoints: An application to a single‐arm, pilot non‐Hodgkin's lymphoma trial
Authors: Mahnken Jonathan D. , Wick Jo A. , Gajewski Byron J. , Mayo Matthew S.
Published: October 2010

Optimizing study designs is an important responsibility for applied statisticians supporting clinical trials. We describe the study design for an early‐phase non‐Hodgkin's lymphoma trial with two co‐primary endpoints; however, evaluation of the second endpoint on a subject is conditional on a positive response to the first endpoint. Thus, these dichotomous measures are collected conditionally and in series. We present the probability density function for this study design selected and derive the parameters that describe this distribution. We also derive the maximum likelihood estimates for the unknown parameters of interest to the trial investigator. We compare the theoretical operating characteristics (type I and type II error rates) to a simulation study for the motivating example. Using this report as a guide, others designing studies with similarly measured co‐primary endpoints can utilize these formulas to calculate the operating characteristics and analyze their resulting study data. Drug Dev Res 71: 395–403, 2010.  © 2010 Wiley‐Liss, Inc.
Synthesis and evaluation as PDE4 inhibitors of pyrimidine‐2,4‐dione derivatives
Authors: Giovannoni Maria P. , Graziano Alessia , Matucci Rosanna , Nesi Marta , Cesari Nicoletta , Vergelli Claudia , Biancalani Claudio , Crocetti Letizia , Cilibrizzi Agostino , Dal Piaz Vittorio
Published: October 2010

A series of nitraquazone analogs with a pyrimidindione core was synthesized and tested for inhibitory activity on PDE4, selectivity versus PDE3 and PDE5 and for affinity towards the rolipram high‐affinity binding site (HARBS). The 5‐anilino derivatives 13–18 showed the best profile combining appreciable PDE4 inhibitory activity (IC50= 5–14 µM) with a good selectivity toward PDE3 and PDE5. The same compounds demonstrate low affinity for the HARBS site with IC50values of 12–69 µM (IC50for Rolipram = 3.6 nM). Drug Dev Res 72: 274–288, 2011. © 2010 Wiley‐Liss, Inc.
Dynamics of wetland vegetation under multiple stresses: a case study of changes in sawgrass trait, structure, and productivity under coupled plant‐soil‐ microbe dynamics
Authors: Muneepeerakul Chitsomanus P. , Muneepeerakul Rachata , Miralles‐Wilhelm Fernando , Rinaldo Andrea , Rodriguez‐Iturbe Ignacio
Published: October 2010

This paper quantifies wetland vegetation dynamics under drought, waterlogging, shading, and nutrient stresses within the coupled plant‐soil‐microbe system. A plant is characterized by three independent traits, namely leaf nitrogen (N) content, specific leaf area (SLA), and allometric carbon (C) allocation to rhizome storage, while plant growth is modelled through a dynamic plant allocation scheme. The modelling of N focuses on the internal cycle in which the aerobic and anaerobic processes are determined by the dynamics of oxygen controlled by plants, microbial aerobic processes, and hydrologic dynamics. The dynamics of water levels and soil moisture are described by a simple hydrologic model with stochastic rainfall and are decoupled from the plant‐soil‐microbe dynamics. Using the model to investigate the dynamics of sawgrass, the results, which are consistent with field observations in the southern Everglades, indicate that SLA decreases with increasing anaerobic condition. The lower SLA maintains high stomatal opening, while at the same time prevents cavitational collapse when sawgrass lowers its root:shoot ratio to reduce C cost in root anaerobic respiration. Given a naturally low but not too scarce level of phosphorus, net N mineralization is higher in the wetter hydrologic regimes because the increase in anaerobic decomposition and N mineralization compensate for the decline in those of aerobes; and the slower growing, more nitrogen efficient anaerobes compete less with plants for N. The optimal traits are the results of several counteracting trends of trade‐offs in C and N economy differently influenced by trait combinations in different wetland environments. Copyright © 2010 John Wiley & Sons, Ltd.
A New Building Block for Organometallic–Inorganic Hybrid Polymers: The Mixed Group 15/16 Element Ligand Complex [Cp*2Mo2(μ,η2:2‐PSe)2(μ‐Se)] (Cp* = C5Me5)
Authors: Bodensteiner Michael , Dušek Michal , Kubicki Marek M. , Pronold Michael , Scheer Manfred , Wachter Joachim , Zabel Manfred
Published: October 2010

The synthesis and spectroscopic characterization of [Cp*2Mo2P2Se3] (1; Cp* = C5Me5) and its use as a molecular building block in the formation of copper(I) halide polymers is described. The reaction of 1 in CH2Cl2 with 2 equiv. of CuBr and CuI in CH3CN under diffusion conditions gave [(Cp*2Mo2P2Se3)2(CuBr)2] (2) and [(Cp*2Mo2P2Se3)(CuX)3(CH3CN)]n (X = I; 3/4), respectively. The structure of 2 is distinguished by a central Cu2Br2 ring coordinated on each side by a tripledecker complex through one of its P atoms. A 2D network is formed by weak interactions between Se atoms of neighboring molecules. Compound [(Cp*2Mo2P2Se3)(CuI)3(CH3CN)]n exists in two isomeric forms 3 and 4. The crystal structure of 3 can be described as a two‐dimensional polymer that is formed by ribbons containing looped chains of three Cu2I2 rings and attached [Cp*2Mo2P2Se3] molecules. The structure of 4 contains a ribbon in which tripledecker molecules are linked through their P atoms to (CuI)6 clusters. The ribbons are connected by weak Se···Se interactions. The reaction of a mixture of 1 and P4Se3 with CuI gave [(Cp*2Mo2P2Se3)(P4Se3)(CuI)2]n. The crystal structure analysis of 5 reveals a new type of organometallic–inorganic framework in which 1 and P4Se3 are linked by Cu2I2 rings.
Zeo‐Click Chemistry: Copper(I)–Zeolite‐Catalyzed Cascade Reaction; One‐Pot Epoxide Ring‐Opening and Cycloaddition
Authors: Boningari Thirupathi , Olmos Andrea , Reddy Benjaram M. , Sommer Jean , Pale Patrick
Published: October 2010

Copper(I)‐modified zeolites, especially CuI–USY, proved to be very efficient catalysts in multi‐component reactions of epoxides with sodium azide and terminal alkynes. Such catalysts allow highly regio‐ and stereoselective syntheses ofhydroxymethylated triazoles. These heterogeneous, modified zeolites can easily be recovered and reused. Moreover, the cascade reaction was best performed in water at room temperature, rendering all the processes truly green. Detailed investigations revealed the role the CuI‐modified zeolites play both during the epoxide ring‐opening and cycloaddition steps.
Fluoroalkylated α,β‐Unsaturated Imines: Efficient and Versatile Substrates for the Synthesis of Fluorinated Vinylogous β‐Amino Esters and 3,4‐Dihydropyridin‐2‐ones
Authors: Palacios Francisco , Ochoa de Retana Ana M. , Pascual Sergio , de Trocóniz Guillermo Fernández , Ezpeleta José M.
Published: October 2010

A simple and efficient synthesis of vinylogous fluoroalkylated β‐amino mono‐ (4) and diester (9) derivatives by the regioselective 1,2‐addition of enolates derived from alkyl acetates or diethyl malonate to fluoroalkylated α,β‐unsaturated imines (1) is described. These fluorinated imines (1) were used as intermediates in the regioselective synthesis of fluorine‐containing trans‐3,4‐dihydropyridin‐2‐ones (6, 8a, 8b, 10) and 3,3‐spiro‐3,4‐dihydropyridin‐2‐ones (8c–h) by conjugate (1,4‐) addition of enolates derived from α‐mono‐ and α,α‐disubstituted esters. Fluoroalkylated β‐amino esters (4, 9) and 3,4‐dihydropyridin‐2‐ones (6, 8, 10) were also prepared by the olefination of enaminophosphonate 2 with BuLi, addition of aldehydes and subsequent addition of the enolates derived from esters 3.
Seismic response evaluation of an urban overpass
Authors: Mayoral Juan M. , Flores Francisco A. , Romo Miguel P.
Published: October 2010

The seismic response of one section of a 23 km strategic urban overpass to be built in the so‐called transition and hill zones in Mexico City is presented. The subsoil conditions at these zones typically consist on soft to stiff clay and medium to dense sand deposits, randomly interbedded by loose sand lenses, and underlain by rock formations that may outcrop in some areas. Several critical supports of this overpass are going to be instrumented with accelerometers, inclinometers and extensometers, tell tales and end pile cell pressures to assess their seismic performance during future earthquakes and to generate a database to calibrate soil–structure interaction numerical models. This paper presents the seismic performance evaluation of the critical supports located in one section of the overpass. Sets of finite elements models of the soil–foundation–structure systems were developed. Initially, the model was calibrated analyzing the seismic response that an instrumented bridge support exhibited during the June 15th, 1999 Tehuacan (Mw = 7) Earthquake. This bridge is located also within the surroundings of Mexico City, but in the lake zone, where highly compressible clays are found. The computed response was compared with the measured response in the free field, pile‐box foundation and bridge deck. Once the model prediction capabilities were established, the seismic response of the critical supports of the urban overpass was evaluated for the design earthquake in terms of transfer functions and displacement time histories. Copyright © 2010 John Wiley & Sons, Ltd.
Iterative implicit integration procedure for hybrid simulation of large nonlinear structures
Authors: Mosqueda G. , Ahmadizadeh M.
Published: October 2010

A fully implicit iterative integration procedure is presented for local and geographically distributed hybrid simulation of the seismic response of complex structural systems with distributed nonlinear behavior. The purpose of this procedure is to seamlessly incorporate experimental elements in simulations using existing fully implicit integration algorithms designed for pure numerical simulations. The difficulties of implementing implicit integrators in a hybrid simulation are addressed at the element level by introducing a safe iteration strategy and using an efficient procedure for online estimation of the experimental tangent stiffness matrix. In order to avoid physical application of iterative displacements, the required experimental restoring force at each iteration is estimated from polynomial curve fitting of recent experimental measurements. The experimental tangent stiffness matrix is estimated by using readily available experimental measurements and by a classical diagonalization approach that reduces the number of unknowns in the matrix. Numerical and hybrid simulations are used to demonstrate that the proposed procedure provides an efficient method for implementation of fully implicit numerical integration in hybrid simulations of complex nonlinear structures. The hybrid simulations presented include distributed nonlinear behavior in both the numerical and experimental substructures. Copyright © 2010 John Wiley & Sons, Ltd.
Modelling the effect of time‐dependent river dune evolution on bed roughness and stage
Authors: Paarlberg Andries J. , Dohmen‐Janssen C. Marjolein , Hulscher Suzanne J. M. H. , Termes Paul , Schielen Ralph
Published: October 2010

This paper presents an approach to incorporate time‐dependent dune evolution in the determination of bed roughness coefficients applied in hydraulic models. Dune roughness is calculated by using the process‐based dune evolution model of Paarlberg et al. (2009) and the empirical dune roughness predictor of Van Rijn (1984). The approach is illustrated by applying it to a river of simple geometry in the 1‐D hydraulic model SOBEK for two different flood wave shapes. Calculated dune heights clearly show a dependency on rate of change in discharge with time: dunes grow to larger heights for a flood wave with a smaller rate of change. Bed roughness coefficients computed using the new approach can be up to 10% higher than roughness coefficients based on calibration, with the largest differences at low flows. As a result of this larger bed roughness, computed water depths can be up to 15% larger at low flow. The new approach helps to reduce uncertainties in bed roughness coefficients of flow models, especially for river systems with strong variations in discharge with time. Copyright © 2010 John Wiley & Sons, Ltd.
Automatic transition from simulation to one‐shot shape optimization with Navier‐Stokes equations
Authors: Özkaya Emre , Gauger Nicolas R.
Published: October 2010

We introduce the one‐shot method and its application to aerodynamic shape optimization, where the governing equations are the incompressible Reynolds‐Averaged Navier‐Stokes (RANS) equations in combination with the k – ω turbulence model. We constrain the one‐shot strategy to problems, where steady‐state solutions are achieved by fixed‐point iteration schemes. The one‐shot optimization strategy pursues optimality simultaneously with the goals of primal and adjoint feasibility. To exploit the domain specific experience and expertise invested in the simulation tools, we propose to extend them in an automated fashion by the use of automatic differentiation (AD) tools. First, they are automatically augmented with an adjoint solver to obtain (reduced) derivatives and then this sensitivity information is immediately used to determine optimization corrections (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)