bluuebunny/crossref_metadata_2025 huggingface dataset:
Neck treatment and shoulder morbidity: Still a challenge
Authors: Bradley Patrick J. , Ferlito Alfio , Silver Carl E. , Takes Robert P. , Woolgar Julia A. , Strojan Primož , Suárez Carlos , Coskun Hakan , Zbären Peter , Rinaldo Alessandra
Published: October 2010

Shoulder complaints and functional impairment are common sequelae of neck dissection. This is often attributed to injury of the spinal accessory nerve by dissection or direct trauma. Nevertheless, shoulder morbidity may also occur in cases in which the spinal accessory nerve has been preserved. In this article, the physiology and pathophysiology of the shoulder are discussed, followed by a consideration of the impact of neck dissection on shoulder complaints, functional impairment, and quality of life. Finally, rehabilitation will be considered. © 2010 Wiley Periodicals, Inc. Head Neck, 2011
Outcomes after definitive treatment for cutaneous angiosarcoma of the face and scalp
Authors: Guadagnolo B. Ashleigh , Zagars Gunar K. , Araujo Dejka , Ravi Vinod , Shellenberger Thomas D. , Sturgis Erich M.
Published: October 2010

Background

The aim of the present analysis was to retrospectively evaluate outcomes in patients with cutaneous angiosarcoma of the face/scalp treated curatively with surgery, radiation therapy (RT), or a combination of surgery and RT.

Methods

In all, 70 patients with nonmetastatic angiosarcoma underwent surgery, RT, or combined‐modality therapy. Of these, 20 patients (29%) were treated with surgery alone, 27 patients (39%) with RT alone, and 23 patients (33%) with combined‐modality therapy; 44 patients received chemotherapy, either neoadjuvantly or adjuvantly or both.

Results

Median follow‐up was 2.1 years. The overall survival (OS) rate was 43% at 5 years, and disease‐specific survival (DSS) was 46% at 5 years. Tumor size > 5 cm and satellitosis were prognostic for inferior OS and DSS. Combined‐modality therapy (vs surgery alone or RT alone) was associated with improved OS, DSS, and local control.

Conclusions

Primary local therapy with combined‐modality therapy was associated with improved local control, OS, and DSS for patients with angiosarcoma of the face/scalp. © 2010 Wiley Periodicals, Inc. Head Neck, 2011
Evaluation of a hydrothermal process for pretreatment of wheat straw—effect of particle size and process conditions
Authors: Ruiz Héctor A. , Ruzene Denise S. , Silva Daniel P. , Quintas Mafalda A.C. , Vicente António A. , Teixeira José A.
Published: October 2010

BACKGROUND: Hydrothermal processes are an eco‐friendly processes that provide an interesting alternative for chemical utilization of lignocellulosic materials, in which water and crop residues are the only reagents. In this work the effect of process conditions (size distribution of the wheat straw, temperature and time) was evaluated against production of fermentable products.

RESULTS: The use of milled wheat straw fractions as a raw material containing blends of different particle size distribution showed that the latter had an influence on the final sugars in the hydrolysate. Improved values of glucose (21.1%) and xylose yields (49.32%) present in the hydrolysate were obtained with treatment severity factors of 2.77 and 3.36, respectively. Mathematical models were developed aimed at establishing the effect of process conditions on monosaccharide concentration and its degradation in the liquor.

CONCLUSION: This work shows that the use of wheat straw blends with various particle sizes has a significant effect on the extraction of fermentable products. The effect of treatment severity, which takes into account both processing time and temperature was also evaluated. These results are of importance for process design. Copyright © 2010 Society of Chemical Industry
Production of olefins from ethanol by Fe and/or P‐modified H‐ZSM‐5 zeolite catalysts
Authors: Inaba Megumu , Murata Kazuhisa , Takahara Isao , Inoue Ken‐ichiro
Published: October 2010

BACKGROUND: Much attention has been paid to the catalytic conversion of ethanol to olefins, since biomass resources such as ethanol are carbon‐neutral and renewable, and olefins are useful as both fuels and chemicals. It has been reported that zeolite H‐ZSM‐5 is effective for converting ethanol to hydrocarbons, with the chief products being aromatic compounds.

RESULTS: Successive addition of Fe and P to the H‐ZSM‐5 improved the initial selectivity for propylene, while the sole addition of Fe or P and co‐addition of Fe and P showed medium initial selectivity. In general, catalysts showing higher initial selectivity for propylene exhibited a steeper decrease in propylene selectivity with time on‐stream. The cause of the change in product selectivity may be carbon deposition during reaction. Addition of Fe and P can improve catalytic stability when processing both neat and aqueous ethanol. The catalytic performance was regenerated by calcination in flowing air.

CONCLUSION: Fe‐ and/or P‐modified H‐ZSM‐5 zeolite catalysts efficiently produced olefins (especially propylene) from ethanol. Effective catalyst regeneration was achieved by calcination in flowing air. Copyright © 2010 Society of Chemical Industry
Adsorption of lanthanum by magnetic alginate‐chitosan gel beads
Authors: Wu Dongbei , Zhang Ling , Wang Li , Zhu Baohui , Fan Liyan
Published: October 2010

BACKGROUND: The risk of environmental pollution is aggravated by the increasing application of considerable amounts of rare earth elements in advanced materials. This paper reports the preparation of novel magnetic alginate–chitosan gel beads and their application for adsorption of lanthanum ions from aqueous solution.

RESULTS: Stable magnetic alginate–chitosan gel beads with average diameter 0.85 ± 0.05 mm were prepared by loading iron oxide nanoparticles onto a combined alginate and chitosan absorbent. The performance of the prepared beads for the adsorption of lanthanum ions from aqueous solution was tested. It was found that various parameters, such as aqueous pH, contact time, metal ion concentration, ion strength and temperature, have an effect on the adsorption. Adsorption equilibrium was reached in 10 h and the maximum uptake capacity was 97.1 mg g−1. From the analysis of pH, FTIR and XPS data, it is proposed that lanthanum adsorption proceeds through mechanisms of cation exchange, electrostatic interaction and surface complexation, with the oxygen atoms the main binding sites. In addition, lanthanum ions could be selectively separated from coexisting base metal ions such as Pb (II), Cd (II), Co (II), Ni (II) and Cu (II) in the aqueous solution.

CONCLUSION: The prepared magnetic alginate–chitosan gel beads exhibit high uptake capacity and selectivity for lanthanum sorption, and thus can be used for adsorptive recovery of lanthanum from aqueous solutions. Copyright © 2010 Society of Chemical Industry
Developmental expression of neuromodulators in the central complex of the grasshopper Schistocerca gregaria
Authors: Herbert Zsofia , Rauser Sandra , Williams Leslie , Kapan Neval , Güntner Michaela , Walch Axel , Boyan George
Published: October 2010

The central complex is a major integrative region within the insect brain with demonstrated roles in spatial orientation, the regulation of locomotor behavior, and sound production. In the hemimetabolous grasshopper, the central complex comprises the protocerebral bridge, central body (CB), ellipsoid body, noduli, and accessory lobes, and this modular organization develops entirely during embryogenesis. From a biochemical perspective, a range of neuroactive substances has been demonstrated in these modules of the adult central complex, but little is known about their developmental expression. In this study, we use matrix‐assisted laser desorption/ionization‐imaging mass spectrometry on single brain slices to confirm the presence of several peptide families (tachykinin, allatostatin, periviscerokinin/pyrokinin, FLRFamide, and neuropeptide F) in the adult central complex and then use immunohistochemistry and histology to examine their developmental expression, together with that of the indolamin serotonin, and the endogenous messenger nitric oxide (NO; via its synthesizing enzyme). We find that each neuromodulator is expressed according to a unique, stereotypic, pattern within the various modules making up the central complex. Neuropeptides such as tachykinin (55%) and allatostatin (65%), and the NO‐synthesizing enzyme diaphorase (70%), are expressed earlier during embryonic development than the biogenic amine serotonin (80%), whereas periviscerokinin‐like peptides and FLRFamide‐like peptides begin to be expressed only postembryonically. Within the CB, these neuroactive substances are present in tangential projection neurons before they appear in columnar neurons. There is also no colocalization of serotonin‐positive and peptide‐positive projections up to the third larval instar during development, consistent with the clear dorsoventral layering of the neuropil we observe. Our results provide the first neurochemical fingerprint of the developing central complex in an hemimetabolous insect. J. Morphol., 2010. © 2010 Wiley‐Liss, Inc.
Modeling the effects of cingula structure on strain patterns and potential fracture in tooth enamel
Authors: Anderson Philip S.L. , Gill Pamela G. , Rayfield Emily J.
Published: October 2010

The mammalian cingulum is a shelf of enamel, which rings the base of the molar crown (fully or partially). Certain nonmammalian cynodonts show precursors of this structure, indicating that it may be an important dental character in the origins of mammals. However, there is little consensus as to what drove the initial evolution of the cingulum. Recent work on physical modeling of fracture mechanics has shown that structures which approximate mammalian dentition (hard enamel shell surrounding a softer/tougher dentine interior) undergo specific fracture patterns dependent on the material properties of the food items. Soft materials result in fractures occurring at the base of the stiff shell away from the contact point due to heightened tensile strains. These tensile strains occur around the margin in the region where cingula develop. In this article, we test whether the presence of a cingulum structure will reduce the tensile strains seen in enamel using basic finite element models of bilayered cones. Finite element models of generic cone shaped “teeth” were created both with and without cingula of various shapes and sizes. Various forces were applied to the models to examine the relative magnitudes and directions of average maximum principal strain in the enamel. The addition of a cingulum greatly reduces tensile strains in the enamel caused by “soft‐food” forces. The relative shape and size of the cingulum has a strong effect on strain magnitudes as well. Scaling issues between shapes are explored and show that the effectiveness of a given cingulum to reducing tensile strains is dependent on how the cingulum is created. Partial cingula, which only surround a portion of the tooth, are shown to be especially effective at reducing strain caused by asymmetrical loads, and shed new light on the potential early function and evolution of mammalian dentitions. J. Morphol., 2011. © 2010 Wiley‐Liss, Inc.
Examination of the surface heterogeneity of reversed‐phase packing materials with solvent adsorption
Authors: Vajda Péter , Bocian Szymon , Buszewski Bogusław , Felinger Attila
Published: October 2010

The adsorption isotherms of acetonitrile, ethanol, 2‐propanol, and THF were measured using frontal analysis on six columns packed with octadecyl RP stationary phase. The effect of the bonding density of the end‐capped octadecyl bonded phase on the adsorption properties was measured. Adsorption isotherm data were collected from aqueous solutions of the four organic modifiers. The isotherm model for solvent adsorption was selected using two independent parameter estimation methods, the regression analysis and adsorption energy distribution. The fitted isotherm parameters were tested by modeling of overloaded elution bands with the aid of the equilibrium‐dispersive model of chromatography. The surface heterogeneity estimations and the effect of the silanol groups on the adsorption of solvents were based on those data.
Characterization of branched polysaccharides using multiple‐detection size separation techniques
Authors: Vilaplana Francisco , Gilbert Robert G.
Published: October 2010

The structure of branched polysaccharides involves a hierarchy of levels, from the constituent sugars, then the branching pattern, up to the macromolecular architecture, and then supramolecular organization. Finding causal relations between this complex structure/architecture and both (bio)synthetic mechanisms and final properties is needed for understanding the functionality of branched polysaccharides, which is important in fields ranging from improved nutrition and health through to papermaking and pharmaceuticals. The structural complexity makes this task especially challenging. This review focuses on the best current means to obtain reliable branch chain and size distributions using size‐separation technologies coupled with number‐, mass‐ and molecular‐weight‐sensitive detectors. Problems with current technologies are also critically appraised.
Retraction: Are conjugated linoleic acid (CLA) isomers good or bad trans fats?
Authors: Yavari Alireza , Hamedi Manouchehr , Heshmati Ali , Haghbin Sahahede
Published: October 2010

Even though trans fatty acids (TFAs) are present in natural sources such as foods from ruminant origins, the development of partially hydrogenated vegetable oil contributed to a significant increase in total TFAs consumption in humans. Currently, TFA consumption is considered to be a risk factor for coronary heart diseases. Researchers are now starting to discover that not all TFAs behave in a similar manner, that is, isomer specificity may be found. Among non‐conjugated TFAs, plant originated TFAs (mainly elaidic and linolelaidic acids) are particularly linked to increased risk for coronary heart diseases, while animal originated TFAs (mainly vaccenic acid) are not. Among conjugated TFAs, two major isomers of conjugated linoleic acid (CLA), cis‐9, trans‐11 and trans‐10, cis‐12, show distinctive biological activities. A number of clinical trials of CLA with effects on body composition have been reported, but effects on coronary heart disease risk factors have been inconsistent. Meanwhile, safety concerns regarding CLA, in particular isomer specificity, have also been raised. Thus, it is critical to identify isomer specific effects of TFAs on particular risk factors, to determine their health impact.
Marine phospholipids as dietary carriers of long‐chain polyunsaturated fatty acids
Authors: Cansell Maud
Published: October 2010

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are polyunsaturated fatty acids (PUFA) of the n‐3 series. Fish oil is a classical source of n‐3 PUFA, where they occur in the form of triacylglycerols (TAG). However, new sources of n‐3 PUFA esterified in phospholipids (PL) are emerging. We prepared liposomes from a natural marine lipid extract and examined their behaviour under conditions mimicking that of the gastrointestinal tract. This physicochemical approach proved that liposomes could be used as an effective oral PUFA delivery system. In vivo studies in rats were performed to examine the metabolic fate of EPA (20:5 n‐3) and DHA (22:6 n‐3) delivered either in PL from liposomes or in TAG from oil. Liposome ingestion increased PUFA bioavailability in lymph compared with fish oil. The proportion of n‐3 PUFA esterified in the sn‐2 position of chylomicron TAG depended on the dietary lipid source. Complex time‐course profiles were observed for plasma lipids with liposome supplementation over a 2‐week period, suggesting time‐dependent regulations. Taken together, the type of PUFA, EPA or DHA, as well as its intramolecular distribution in chylomicron TAG seemed to influence the metabolic fate of the fatty acids and their physiological activities.
Effect of a Nitroxyle‐Based Radical Scavenger on Nanotube Functionalisation with Pentadecane: A Model Compound Study for Polyethylene Grafting onto MWCNTs
Authors: Akbar Sohaib , Beyou Emmanuel , Chaumont Philippe , Melis Flavien
Published: October 2010

The radical grafting of pentadecane onto MWCNTs has been investigated. A model for the functionalisation of MWCNTs with molten polyethylene is established, in which a pentadecane radical grafting reaction has been studied in order to determine the reaction conditions necessary to enhance the degree of grafting while minimising side reactions such as radical combination reactions. The effect of a nitroxyle‐based radical scavenger (such as TEMPO) on the competition between the recombination of pentadecane radicals and addition to nanotubes has been explored. It was observed that the use of TEMPO resulted in a relatively higher grafting density without excessive pentadecane branching/crosslinking.

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Preparation of a Rapidly Forming Poly(ferrocenylsilane)‐Poly(ethylene glycol)‐based Hydrogel by a Thiol‐Michael Addition Click Reaction
Authors: Sui Xiaofeng , van Ingen Lennard , Hempenius Mark A. , Vancso G. Julius
Published: October 2010

The synthesis of a rapidly forming redox responsive poly(ferrocenylsilane)‐poly(ethylene glycol) (PFS‐PEG)‐based hydrogel is described, achieved by a thiol‐Michael addition click reaction. PFS bearing acrylate side groups (PFS‐acryl) was synthesized by side group modification of poly(ferrocenyl(3‐iodopropyl)methylsilane) (PFS‐I) and characterized by 1H NMR, 13C NMR, and FT‐IR spectroscopy. The equilibrium swelling ratio, morphology, rheology, and redox responsive properties of the PFS‐PEG‐based hydrogel are reported.

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Entanglement Transition in Hyperbranched Polyether‐Polyols
Authors: Tonhauser Christoph , Wilms Daniel , Korth Yasmin , Frey Holger , Friedrich Christian
Published: October 2010

Are hyperbranched polymers capable of forming entanglements? This is the central issue of this contribution. Hyperbranched polyglycerol (hbPG) samples with different molecular weights (600–106 000 g · mol−1), narrow polydispersities (1.2–1.8) and high degrees of branching (≈0.6) were prepared by anionic ring‐opening polymerization. The viscoelastic properties of these polymers with respect to molecular architecture and molar mass were investigated. At low molecular weights “classical” scaling behavior between zero shear viscosity and molecular weight can be observed, whereas between 3 000 and 10 000 g · mol−1a plateau‐like area is found. The results indicate entanglement dynamics when exceeding a critical molar mass ($\overline {M} _{{\rm c}}^{*} $ ≈ 20 000 g · mol−1) due to entangled hyperbranched polyglycerols.

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Effect of quenching temperature on structure and abrasive wear resistance of boron‐containing medium carbon steel
Authors: Dang K. , Kuang J. , Ye C. , Fu D. , Huang L. , Fu H.
Published: October 2010

Under the condition of oil cooling, the effect of quenching temperatures on the structure and abrasive wear resistance of medium carbon steel containing 2% B has been studied. The results show that the metallic matrix of Boron‐containing Medium Carbon Steel (BMCS) transforms into the martensite from the mixture of martensite, pearlite and ferrite while quenching at 900°C – 1050°C. The change of boron carbide existing in BMCS is few in different quenching temperature. After quenching the hardness of BMCS excels 56 HRC, and the change of quenching temperature has no obvious effect on the hardness of BMCS. The increase of quenching temperature leads to the increase of impact toughness, and impact toughness has no obvious change when quenching temperature exceeds 1000°C. Moreover, the increase of quenching temperature leads to a slight decrease of weight loss and the abrasive wear resistance of BMCS has a slight increase while increasing quenching temperature. Quenching at 1000°C–1050°C BMCS has excellent comprehensive property.
Predicting the Flexibility Profile of Ribosomal RNAs
Authors: Tian Feifei , Zhang Chun , Fan Xia , Yang Xue , Wang Xi , Liang Huaping
Published: October 2010

Flexibility in biomolecules is an important determinant of biological functionality, which can be measured quantitatively by atomic Debye–Waller factor or B‐factor. Although numerous works have been addressed on theoretical and computational studies of the B‐factor profiles of proteins, the methods used for predicting B‐factor values of nucleic acids, especially the complicated ribosomal RNAs (rRNAs), which are very functionally similar to proteins in providing matrix structures and in catalyzing biochemical reactions, still remain unexploited. In this article, we present a quantitative structure–flexibility relationship (QSFR) study with the aim at the quantitative prediction of rRNA B‐factor based on primary sequences (sequence‐based) and advanced structures (structure‐based) by using both linear and nonlinear machine learning approaches, including partial least squares regression (PLS), least squares support vector machine (LSSVM), and Gaussian process (GP). By rigorously examining the performance and reliability of constructed statistical models and by comparing our models in detail to those developed previously for protein B‐factors, we demonstrate that (i) rRNA B‐factors could be predicted at a similar level of accuracy with that of protein, (ii) a structure‐based approach performed much better as compared to sequence‐based methods in modeling of rRNA B‐factors, and (iii) rRNA flexibility is primarily governed by the local features of nonbonding potential landscapes, such as electrostatic and van der Waals forces.
Morphology, crystallization and enzymatic hydrolysis of poly(L‐lactide) nucleated using layered metal phosphonates
Authors: Wang Shusheng , Han Changyu , Bian Junjia , Han Lijing , Wang Xuemei , Dong Lisong
Published: October 2010

Poly(L‐lactide) (PLLA) was prepared via melt blending and nucleated using three layered metal phosphonates, i.e. zinc phenylphosphonate (PPZn), calcium phenylphosphonate (PPCa) and barium phenylphosphonate (PPBa). The morphology, crystallization and enzymatic hydrolysis of PLLA nucleated using PPZn, PPCa and PPBa were investigated. The results of both wide‐angle X‐ray diffraction and transmission electron microscopy observations show that the layers of PPZn, PPCa or PPBa are barely exfoliated or intercalated by PLLA chains in the melt‐blending process. PPZn, PPCa and PPBa serve as effective nucleating agents, accelerating both non‐isothermal and isothermal crystallization and enzymatic hydrolysis of PLLA. An interesting aspect is that the nucleating ability of PLLA incorporating PPZn, PPCa and PPBa decreases in the order PPZn > PPCa > PPBa, whereas the enzymatic hydrolysis of PLLA incorporating PPZn, PPCa and PPBa decreases in the reverse order, which is due to the different dispersion and interfacial interactions of PPZn, PPCa and PPBa throughout the PLLA matrix. Copyright © 2010 Society of Chemical Industry
Melt electrospinning of polycaprolactone and its blends with poly(ethylene glycol)
Authors: Detta Nicola , Brown Toby D , Edin Fredrik K , Albrecht Krystyna , Chiellini Federica , Chiellini Emo , Dalton Paul D , Hutmacher Dietmar W
Published: October 2010

Melt electrospinning is one aspect of electrospinning with relatively little published literature, although the technique avoids solvent accumulation and/or toxicity which is favoured in certain applications. In the study reported, we melt‐electrospun blends of poly(ε‐caprolactone) (PCL) and an amphiphilic diblock copolymer consisting of poly(ethylene glycol) and PCL segments (PEG‐block‐PCL). A custom‐made electrospinning apparatus was built and various combinations of instrument parameters such as voltage and polymer feeding rate were investigated. Pure PEG‐block‐PCL copolymer melt electrospinning did not result in consistent and uniform fibres due to the low molecular weight, while blends of PCL and PEG‐block‐PCL, for some parameter combinations and certain weight ratios of the two components, were able to produce continuous fibres significantly thinner (average diameter of ca 2 µm) compared to pure PCL. The PCL fibres obtained had average diameters ranging from 6 to 33 µm and meshes were uniform for the lowest voltage employed while mesh uniformity decreased when the voltage was increased. This approach shows that PCL and blends of PEG‐block‐PCL and PCL can be readily processed by melt electrospinning to obtain fibrous meshes with varied average diameters and morphologies that are of interest for tissue engineering purposes. Copyright © 2010 Society of Chemical Industry
Synthesis and computational oxidation mechanism study of novel organosoluble aramids with high modulus by low‐temperature solution polycondensation
Authors: Chang Cheng‐Hung , Wang Kun‐Li , Jiang Jyh‐Chiang , Liaw Der‐Jang , Lee Kueir‐Rarn , Lai Juin‐Yih , Chiu Kuo Yuan , Su Yuhlong Oliver
Published: October 2010

A series of highly organosoluble polyamides with high modulus having propeller‐shaped triarylamine were synthesized using aromatic diacid chlorides by low‐temperature solution polycondensation. The polyamide films had strong, tough, flexible, and amorphous properties. These polymers revealed electrochromic characteristics both in the visible range and near‐infrared (NIR) region, with a color change from pale yellowish at its neutral state to green and blue at its oxidized state at applied potentials ranging from 0.00 to 1.35 V. Cyclic voltammetry (CV) of the polymer films cast onto an indium tin oxide (ITO)‐coated glass substrate exhibited two reversible redox couples at potentials of 0.80–0.87 V and 1.19–1.25 V, respectively, vs. Ag/Ag+ in acetonitrile solution. From the combination of the experimental and computational study, we proposed an oxidation mechanism based on molecular orbital (MO) theory, which well explains the CV experimental result. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010
Synthesis and characterization of poly(arylene ether ketone)s bearing pendant sulfonic acid groups for proton exchange membrane materials
Authors: Zhang Yang , Zhang Gang , Wan Ying , Zhao Chengji , Shao Ke , Li Hongtao , Han Miaomiao , Zhu Jing , Xu Shuai , Liu Zhongguo , Na Hui
Published: October 2010

A bisphenol monomer (2,5‐dimethoxy)phenylhydroquinone was prepared and further polymerized to obtain poly(arylene ether ketone) copolymers containing methoxy groups. After demethylation and sulfobutylation, a series of novel poly(arylene ether ketone)s bearing pendant sulfonic acid group (SPAEKs) with different sulfonation content were obtained. The chemical structures of all the copolymers were analyzed by 1H NMR and 13C NMR spectra. Flexible and tough membranes with reasonably good mechanical properties were prepared. The resulting side‐chain‐type SPAEK membranes showed good dimensional stability, and their water uptake and swelling ratio were lower than those of conventional main‐chain‐type SPAEK membranes with similar ion exchange capacity. Proton conductivities of these side‐chain‐type sulfonated copolymers were higher than 0.01 S/cm and increased gradually with increasing temperature. Their methanol permeability values were in the range of 1.97 × 10−7–5.81 × 10−7 cm2/s, which were much lower than that of Nafion 117. A combination of suitable proton conductivities, low water uptake, low swelling ratio, and high methanol resistance for these side‐chain‐type SPAEK films indicated that they may be good candidate material for proton exchange membrane in fuel cell applications. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010
XANNpred: Neural nets that predict the propensity of a protein to yield diffraction‐quality crystals
Authors: Overton Ian M. , van Niekerk C. A. Johannes , Barton Geoffrey J.
Published: October 2010

Production of diffracting crystals is a critical step in determining the three‐dimensional structure of a protein by X‐ray crystallography. Computational techniques to rank proteins by their propensity to yield diffraction‐quality crystals can improve efficiency in obtaining structural data by guiding both protein selection and construct design. XANNpred comprises a pair of artificial neural networks that each predict the propensity of a selected protein sequence to produce diffraction‐quality crystals by current structural biology techniques. Blind tests show XANNpred has accuracy and Matthews correlation values ranging from 75% to 81% and 0.50 to 0.63 respectively; values of area under the receiver operator characteristic (ROC) curve range from 0.81 to 0.88. On blind test data XANNpred outperforms the other available algorithms XtalPred, PXS, OB‐Score, and ParCrys. XANNpred also guides construct design by presenting graphs of predicted propensity for diffraction‐quality crystals against residue sequence position. The XANNpred‐SG algorithm is likely to be most useful to target selection in structural genomics consortia, while the XANNpred‐PDB algorithm is more suited to the general structural biology community. XANNpred predictions that include sliding window graphs are freely available from http://www.compbio.dundee.ac.uk/xannpred Proteins 2011. © 2010 Wiley‐Liss, Inc.
Difference in optical properties of anthracene molecule aggregates in fluorene and phenanthrene crystals
Authors: Aoki‐Matsumoto Tamao , Noda Kenta , Mizuno Ken‐ichi
Published: October 2010

Optical properties of anthracene molecules in phenanthrene crystals with anthracene concentration of 0.03% to 8.4% were investigated and compared with those in fluorene crystals. In contrast to fluorene system where two kinds of dimers, one of which is accompanied by lattice relaxation, are observed, it was found that only one kind of dimers without lattice relaxation are observed in phenanthrene system. Also in aggregates of anthracene in higher concentration samples, the luminescence is a ‘free exciton’‐type in phenanthrene crystals in contrast to a ‘self‐trapped exciton’‐type in fluorene crystals. With reference to the variation of the magnitude of exciton–phonon coupling constant on nearest neighbour distance of molecules known for bulk crystals of aromatic molecules, the difference is attributed to longer inter molecular distance between anthracene molecules in phenanthrene matrix in comparison to those in fluorene matrix (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Residual stress study of silicon quantum dot in silicon carbide matrix by Raman measurement
Authors: Wan Zhenyu , Huang Shujuan , Green Martin , Conibeer Gavin
Published: October 2010

Two different annealing processes have been applied on Silicon rich SiCX amorphous samples: furnace annealing at 1100 °C/1hr and RTA at 1100 °C/30 sec. After annealing, both Si and SiC nanocrystals were clearly observed from TEM image and evaluated from XRD results. Peak position of Raman results are more blue shifted from Si reference wafer position in RTA samples (Δ=5.4 cm‐1) compare with furnace annealing samples (Δ=2 cm‐1), indicating greater tensile stress is applied on Si nanocrystals. This is because of different thermal expansion coefficient of Si and SiC crystals and fast temperature ramping rate in RTA process. In order to release the stress in RTA samples, additional annealing process has been applied. Raman analysis indicates, after applying an additional furnace annealing, all samples with different Si concentration could release most of the residual stress. But residual stress in low Si concentration samples could not be as well released by additional RTA due to insufficient time duration. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Nanoparticle Layer Deposition for Plasmonic Tuning of Microstructured Optical Fibers
Authors: Csaki Andrea , Jahn Franka , Latka Ines , Henkel Thomas , Malsch Daniell , Schneider Thomas , Schröder Kerstin , Schuster Kay , Schwuchow Anka , Spittel Ron , Zopf David , Fritzsche Wolfgang
Published: October 2010

Plasmonic nanoparticles with spectral properties in the UV‐to‐near‐IR range have a large potential for the development of innovative optical devices. Similarly, microstructured optical fibers (MOFs) represent a promising platform technology for fully integrated, next‐generation plasmonic devices; therefore, the combination of MOFs and plasmonic nanoparticles would open the way for novel applications, especially in sensing applications. In this Full Paper, a cost‐effective, innovative nanoparticle layer deposition (NLD) technique is demonstrated for the preparation of well‐defined plasmonic layers of selected particles inside the channels of MOFs. This dynamic chemical deposition method utilizes a combination of microfluidics and self‐assembled monolayer (SAM) techniques, leading to a longitudinal homogeneous particle density as long as several meters. By using particles with predefined plasmonic properties, such as the resonance wavelength, fibers with particle‐adequate spectral characteristics can be prepared. The application of such fibers for refractive‐index sensing yields a sensitivity of about 78 nm per refractive index unit (RIU). These novel, plasmonically tuned optical fibers with freely selected, application‐tailored optical properties present extensive possibilities for applications in localized surface plasmon resonance (LSPR) sensing.
Scalable model‐based configuration management of security services in complex enterprise networks
Authors: de Albuquerque João Porto , Krumm Heiko , de Geus Paulo Lício , Jeruschkat René
Published: October 2010

Security administrators face the challenge of designing, deploying and maintaining a variety of configuration files related to security systems, especially in large‐scale networks. These files have heterogeneous syntaxes and follow differing semantic concepts. Nevertheless, they are interdependent due to security services having to cooperate and their configuration to be consistent with each other, so that global security policies are completely and correctly enforced. To tackle this problem, our approach supports a comfortable definition of an abstract high‐level security policy and provides an automated derivation of the desired configuration files. It is an extension of policy‐based management and policy hierarchies, combining model‐based management (MBM) with system modularization. MBM employs an object‐oriented model of the managed system to obtain the details needed for automated policy refinement. The modularization into abstract subsystems (ASs) segment the system—and the model—into units which more closely encapsulate related system components and provide focused abstract views. As a result, scalability is achieved and even comprehensive IT systems can be modelled in a unified manner. The associated tool MoBaSeC (Model‐Based‐Service‐Configuration) supports interactive graphical modelling, automated model analysis and policy refinement with the derivation of configuration files. We describe the MBM and AS approaches, outline the tool functions and exemplify their applications and results obtained. Copyright © 2010 John Wiley & Sons, Ltd.
In Vivo Assessment of the Electrophysiological Integration and Arrhythmogenic Risk of Myocardial Cell Transplantation Strategies
Authors: Gepstein Lior , Ding Chunhua , Rehemedula Dolkun , Wilson Emily E. , Yankelson Lior , Caspi Oren , Gepstein Amira , Huber Irit , Olgin Jeffery E.
Published: October 2010

Cell replacement strategies are promising interventions aiming to improve myocardial performance. Yet, the electrophysiological impact of these approaches has not been elucidated. We assessed the electrophysiological consequences of grafting of two candidate cell types, that is, skeletal myoblasts and human embryonic stem cell-derived cardiomyocytes (hESC-CMs). The fluorescently labeled (DiO) candidate cells were grafted into the rat's left ventricular myocardium. Two weeks later, optical mapping was performed using the Langendorff-perfused rat heart preparation. Images were obtained with appropriate filters to delineate the heart's anatomy, to identify the DiO-labeled cells, and to associate this information with the voltage-mapping data (using the voltage-sensitive dye PGH-I). Histological examination revealed the lack of gap junctions between grafted skeletal myotubes and host cardiomyocytes. In contrast, positive Cx43 immunostaining was observed between donor and host cardiomyocytes in the hESC-CMs-transplanted hearts. Optical mapping demonstrated either normal conduction (four of six) or minimal conduction slowing (two of six) at the hESC-CMs engraftment sites. In contrast, marked slowing of conduction or conduction block was seen (seven of eight) at the myoblast transplantation sites. Ventricular arrhythmias could not be induced in the hESC-CM hearts following programmed electrical stimulation but were inducible in 50% of the myoblast-engrafted hearts. In summary, a unique method for assessment of the electrophysiological impact of myocardial cell therapy is presented. Our results demonstrate the ability of hESC-CMs to functionally integrate with host tissue. In contrast, transplantation of cells that do not form gap junctions (skeletal myoblats) led to localized conduction disturbances and to the generation of a proarrhythmogenic substrate.
Concise Review: Insights from Normal Bone Remodeling and Stem Cell-Based Therapies for Bone Repair
Authors: Khosla Sundeep , Westendorf Jennifer J. , Mödder Ulrike I.
Published: October 2010

There is growing interest in the use of mesenchymal stem cells for bone repair. As a major reason for normal bone remodeling is the removal of fatigue microcracks, advances in our understanding of this process may inform approaches to enhance fracture healing. Increasing evidence now indicates that physiological bone remodeling occurs in close proximity to blood vessels and that these vessels carry perivascular stem cells that differentiate into osteoblasts. Similarly, fracture healing is critically dependent on the ingrowth of blood vessels not only for a nutrient supply but also for the influx of osteoblasts. A number of animal and human studies have now shown the potential benefit of bone marrow-derived mesenchymal stem cells in enhancing bone repair. However, as in other tissues, the question of whether these cells improve fracture healing directly by differentiating into osteoblasts or indirectly by secreting paracrine factors that recruit blood vessels and the accompanying perivascular stem cells remains a major unresolved issue. Moreover, CD34+ cells, which are enriched for endothelial/hematopoietic cells, have also shown efficacy in various bone repair models, at least in part due to the induction of angiogenesis and recruitment of host progenitor cells. Thus, mesenchymal and nonmesenchymal stem/progenitor cells are attractive options for bone repair. It is possible that they contribute directly to bone repair, but it is also likely that they express paracrine factors in the appropriate amounts and combinations that promote and sustain the healing process.
GSK-3β Inhibition Promotes Engraftment of Ex Vivo-Expanded Hematopoietic Stem Cells and Modulates Gene Expression
Authors: Ko Kap-Hyoun , Holmes Tiffany , Palladinetti Patricia , Song Emma , Nordon Robert , O'Brien Tracey A. , Dolnikov Alla
Published: October 2010

Glycogen synthase kinase-3β (GSK-3β) has been identified as an important regulator of stem cell function acting through activation of the wingless (Wnt) pathway. Here, we report that treatment with an inhibitor of GSK-3β, 6-bromoindirubin 3′-oxime (BIO) delayed cell cycle progression by increasing cell cycle time. BIO treatment resulted in the accumulation of late dividing cells enriched with primitive progenitor cells retaining the ability for sustained proliferation. In vivo analysis using a Non-obese diabetic/severe combined immunodeficient (NOD/SCID) transplantation model has demonstrated that pretreatment with BIO promotes engraftment of ex vivo-expanded hematopoietic stem cells. BIO enhanced the engraftment of myeloid, lymphoid and primitive stem cell compartments. Limiting dilution analysis of SCID repopulating cells (SRC) revealed that BIO treatment increased human chimerism without increasing SRC frequency. Clonogenic analysis of human cells derived from the bone marrow of transplant recipient mice demonstrated that a higher level of human chimerism and cellularity was related to increased regeneration per SRC unit. Gene expression analysis showed that treatment with BIO did not modulate the expression of canonical Wnt target genes upregulated during cytokine-induced cell proliferation. BIO increased the expression of several genes regulating Notch and Tie2 signaling downregulated during ex vivo expansion, suggesting a role in improving stem cell engraftment. In addition, treatment with BIO upregulated CDK inhibitor p57 and downregulated cyclin D1, providing a possible mechanism for the delay seen in cell cycle progression. We conclude that transient, pharmacologic inhibition of GSK-3β provides a novel approach to improve engraftment of expanded HSC after stem cell transplantation.
Power, realism, and the ideal of human emancipation in a climate of change
Authors: Manuel‐Navarrete David
Published: October 2010

Most attempts to formalize climate politics have focused on the reform of current governance regimes, including norms, rules, regulations, political will, and decision‐making procedures. Emphasis on reform entails a realist political approach, which only accounts for those incremental changes in power that can be objectively justified in terms of solving practical problems. This paper argues that political realism implicitly supports developmentalist logics of perpetual material growth which are precisely at the root of global environmental problems. Therefore, climate researchers have to move beyond this tradition of political thought, and engage in ‘critical theories’ and idealist approaches that question contemporary power relations. A few scholars have drawn on critical theory, historical materialism, Foucault, and Gramsci to explore power and human emancipation in the context of global environmental politics. These scholars identify hegemonic structures as essential causes of climate change. Accordingly, current power relations need to be fundamentally challenged, not only whenever extreme poverty averts the basic exercise of adaptive capacities, but, more broadly, whenever modernity and globalization set societies on unsustainable paths. This entails, on the one hand, redefining climate change as an opportunity to transform the structures under which modernity and global capitalism take place. On the other hand, it calls for reinterpreting adaptation within a broader project of universal emancipation from the structures that constrain our essential freedom and, with that, hinder effective and just societal responses to the challenges of climate change.WIREs Clim Change2010 1 781–785 DOI: 10.1002/wcc.87

This article is categorized under:

Social Status of Climate Change Knowledge > Sociology/Anthropology of Climate Knowledge
Hemispheric asymmetry: contributions from brain imaging
Authors: Hugdahl Kenneth
Published: October 2010

A series of studies using functional and structural magnetic resonance imaging, including diffusion tensor imaging measures also, to elucidate the aspects of hemispheric asymmetry are reviewed. It is suggested that laterality evolved as a response to the demands of language and the need for air‐based communication which may have necessitated a division of labor between the hemispheres in order to avoid having duplicate copies in both the hemispheres that would increase processing redundancy. This would have put pressure on brain structures related to the evolution of language and speech, such as the left peri‐Sylvian region. MRI data are provided showing structural and functional asymmetry in this region of the brain and how fibers connecting the right and left peri‐Sylvian regions pass through the corpus callosum. It is further suggested that the so‐called Yakelovian‐torque, i.e., the twisting of the brain along the longitudinal axis, with the right frontal and left occipital poles protruding beyond the corresponding left and right sides, was necessary for the expansion of the left peri‐Sylvian region and the right occipito‐parietal regions subserving the processing of spatial relations. Functional magnetic resonance imaging data related to sex differences for visuo‐spatial processing are presented showing enhanced right‐sided activation in posterior parts of the brain in both sexes, and frontal activation including Broca's area in the female group only, suggesting that males and females use different strategies when solving a cognitive task. The paper ends with a discussion of the role of the corpus callosum in laterality and the role played by structural asymmetry in understanding corresponding functional asymmetry.WIREs Cogni Sci2011 2 461–478 DOI: 10.1002/wcs.122

This article is categorized under:

Psychology > Brain Function and Dysfunction
Prevalence and risk factors for domestic violence against infertile women in an Iranian setting
Authors: Ardabily Hasan E. , Moghadam Zahra B. , Salsali Mahvash , Ramezanzadeh Fatemeh , Nedjat Saharnaz
Published: October 2010

Objective

To determine the prevalence of and risk factors for domestic violence against women with female factor infertility in an Iranian setting.

Methods

In this cross‐sectional survey conducted from August 1, 2009 to January 31, 2010, 400 women with primary infertility attending Valiasr Reproductive Health Research Center in Tehran, Iran, were interviewed using the Revised Conflict Tactics Scales questionnaire (CTS2). This instrument was developed to investigate the presence domestic violence.

Results

A total of 247 women (61.8%) reported having experienced domestic violence because of their infertility. The most common type of violence was psychological (n = 135 [33.8%]), followed by physical (n = 56 [14%]) and sexual (n = 32 [8%]), with 24 women (6%) reporting injuries. All women reported their husbands to be the perpetrators.

Conclusion

Domestic violence against infertile women is a considerable yet unreported problem. Clinicians should identify the abused women and provide them with medical care and supportive counseling.
A streamwise constant model of turbulence in plane Couette flow
Authors: GAYME D. F. , McKEON B. J. , PAPACHRISTODOULOU A. , BAMIEH B. , DOYLE J. C.
Published: October 2010

Streamwise and quasi-streamwise elongated structures have been shown to play a significant role in turbulent shear flows. We model the mean behaviour of fully turbulent plane Couette flow using a streamwise constant projection of the Navier–Stokes equations. This results in a two-dimensional three-velocity-component (2D/3C) model. We first use a steady-state version of the model to demonstrate that its nonlinear coupling provides the mathematical mechanism that shapes the turbulent velocity profile. Simulations of the 2D/3C model under small-amplitude Gaussian forcing of the cross-stream components are compared to direct numerical simulation (DNS) data. The results indicate that a streamwise constant projection of the Navier–Stokes equations captures salient features of fully turbulent plane Couette flow at low Reynolds numbers. A systems-theoretic approach is used to demonstrate the presence of large input–output amplification through the forced 2D/3C model. It is this amplification coupled with the appropriate nonlinearity that enables the 2D/3C model to generate turbulent behaviour under the small-amplitude forcing employed in this study.