bluuebunny/crossref_metadata_2025 huggingface dataset:
A combined local damage index for seismic assessment of existing RC structures
Authors: Mergos P. E. , Kappos A. J.
Published: August 2012

A new local damage index for existing RC structures is introduced, wherein deterioration caused by all deformation mechanisms (flexure, shear, anchorage slip) is treated separately for each mechanism. Moreover, the additive character of damage arising from the three response mechanisms, and the increase in degradation rate caused by their interaction, are fully taken into consideration. The proposed local damage index is then applied, in conjunction with a finite element model developed previously by the authors, to assess seismic damage response of several RC column and frame test specimens with substandard detailing. It is concluded that in all cases and independently from the prevailing mode of failure, the new local damage index describes well the damage pattern of the analysed specimens. Copyright © 2012 John Wiley & Sons, Ltd.
Structural behaviour and design criteria of under‐deck cable‐stayed bridges subjected to seismic action
Authors: Camara Alfredo , Ruiz‐Teran Ana M. , Stafford Peter J.
Published: August 2012

Under‐deck cable‐stayed bridges are very effective structural systems for which the strong contribution of the stay cables under live loading allows for the design of very slender decks for persistent and transient loading scenarios. Their behaviour when subjected to seismic excitation is investigated herein and a set of design criteria are presented that relate to the type and arrangement of bearings, the number and configuration of struts, and the transverse distribution of stay cables. The nonlinear behaviour of these bridges when subject to both near‐field and far‐field accelerograms has been thoroughly investigated through the use of incremental dynamic analyses. An intensity measure that reflects the pertinent contributions to response when several vibration modes are activated was proposed and is shown to be effective for the analysis of this structural type. The under‐deck cable‐stay system contributes in a very positive manner to reducing the response when the bridges are subject to very strong seismic excitation. For such scenarios, the reduction in the stiffness of the deck because of crack formation, when prestressed concrete decks are used, mobilises the cable system and enhances the overall performance of the system. Sets of natural accelerograms that are compliant with the prescriptions of Eurocode 8 were also applied to propose a set of design criteria for this bridge type in areas prone to earthquakes. Particular attention is given to outlining the optimal strategies for the deployment of bearings. Copyright © 2012 John Wiley & Sons, Ltd.
PCDD/F release during benthic trawler-induced sediment resuspension
Authors: Allan Ian J. , Nilsson Hans C. , Tjensvoll Ingrid , Bradshaw Clare , Næs Kristoffer
Published: August 2012

Benthic trawling can cause the resuspension of large amounts of sediments. Such regular practice in the Grenland fjord system in the south of Norway has the potential to affect the fate, movement, and bioavailability of sediment-associated polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). A novel mode of exposing passive sampling devices consisting of towing semipermeable membrane devices attached to the trawl net was used to gauge in situ changes in the freely dissolved concentration of PCDD/Fs on benthic trawler–induced sediment resuspension. Significant accumulation of a number of PCDD/F congeners was observed despite the short (5 h) sampler exposure times. On average, a one order of magnitude increase in freely dissolved PCCD/F concentrations was seen within minutes of the sediment being resuspended. This observation was supported by similar changes in filtered PCDD/F concentrations measured by high-volume sampling prior to resuspension and in the sediment plume. Environ. Toxicol. Chem. 2012; 31: 2780–2787. © 2012 SETAC
Distance to hospital and utilization of surgical services in Haiti: do children, delivering mothers, and patients with emergent surgical conditions experience greater geographical barriers to surgical care?
Authors: Friedman James M. , Hagander Lars , Hughes Christopher D. , Nash Katherine A. , Linden Allison F. , Blossom Jeff , Meara John G.
Published: August 2012

Background

An inverse relationship between healthcare utilization and distance to care has been previously described. The purpose of this study was to evaluate this effect related to emergency and essential surgical care in central Haiti.

Methods

We conducted a retrospective review of operative logbooks from the Clinique Bon Sauveur in Cange, Haiti, from 2008 to 2010. We used Geographic Information Systems to map the home locations of all patients. Spearman's correlation was used to determine the relationship between surgical utilization and distance, and a multivariate linear regression model identified characteristics associated with differences in distances traveled to care.

Results

The highest annual surgical utilization rate was 184 operations/100 000 inhabitants. We found a significant inverse correlation between surgical utilization rate and distance from residence to hospital (rs = −0.68, p = 0.02). The median distance from residence to hospital was 55.9 km. Pediatric patients lived 10.1% closer to the hospital than adults (p < 0.01), and distance from residence to hospital was not significantly different between men and women (p = 0.25). Patients who received obstetric or gynecologic surgery originated 7.8% closer to the hospital than patients seeking other operations (p < 0.01), and patients who received emergent surgical care originated 24.8% closer to the hospital than patients who received elective surgery (p < 0.01).

Conclusions

Utilization of surgical services was low and inversely related to distance from residence to hospital in rural areas of central Haiti. Children and patients receiving obstetric, gynecologic or emergent surgery lived significantly closer to the hospital, and these groups may need special attention to ensure adequate access to surgical care. Copyright © 2012 John Wiley & Sons, Ltd.
Silver nanoparticle‐induced oxidative stress, genotoxicity and apoptosis in cultured cells and animal tissues
Authors: Kim Soohee , Ryu Doug‐Young
Published: August 2012

Silver nanoparticles (AgNPs) have emerged as an important class of nanomaterials for a wide range of industrial and medical applications. However, the unique properties of AgNPs could potentially lead to unexpected hazards to both human health and the well being of the environment. Possible mechanisms of AgNP‐induced toxicity include the stimulation of oxidative stress, genotoxicity and apoptosis. In this study, a number of previous studies are therefore summarized that demonstrate oxidative stress‐, genotoxicity‐ and apoptosis‐related changes brought about by AgNPs in cultured cells and animal tissues. The physicochemical properties of AgNPs that are involved in encouraging such changes are also discussed. Copyright © 2012 John Wiley & Sons, Ltd.
Development of a chronic noncancer oral reference dose and drinking water screening level for sulfolane using benchmark dose modeling
Authors: Thompson Chad M. , Gaylor David W. , Tachovsky J. Andrew , Perry Camarie , Carakostas Michael C. , Haws Laurie C.
Published: August 2012

Sulfolane is a widely used industrial solvent that is often used for gas treatment (sour gas sweetening; hydrogen sulfide removal from shale and coal processes, etc.), and in the manufacture of polymers and electronics, and may be found in pharmaceuticals as a residual solvent used in the manufacturing processes. Sulfolane is considered a high production volume chemical with worldwide production around 18 000–36 000 tons per year. Given that sulfolane has been detected as a contaminant in groundwater, an important potential route of exposure is tap water ingestion. Because there are currently no federal drinking water standards for sulfolane in the USA, we developed a noncancer oral reference dose (RfD) based on benchmark dose modeling, as well as a tap water screening value that is protective of ingestion. Review of the available literature suggests that sulfolane is not likely to be mutagenic, clastogenic or carcinogenic, or pose reproductive or developmental health risks except perhaps at very high exposure concentrations. RfD values derived using benchmark dose modeling were 0.01–0.04 mg kg−1 per day, although modeling of developmental endpoints resulted in higher values, approximately 0.4 mg kg−1 per day. The lowest, most conservative, RfD of 0.01 mg kg−1 per day was based on reduced white blood cell counts in female rats. This RfD was used to develop a tap water screening level that is protective of ingestion, viz. 365 µg l−1. It is anticipated that these values, along with the hazard identification and dose–response modeling described herein, should be informative for risk assessors and regulators interested in setting health‐protective drinking water guideline values for sulfolane. Copyright © 2012 John Wiley & Sons, Ltd.
A tyrosine kinase inhibitor‐induced myocardial degeneration in rats through off‐target phosphodiesterase inhibition
Authors: Hu Wenyue , Hirakawa Brad , Jessen Bart , Lee Michelle , Aguirre Shirley
Published: August 2012

PF‐04254644 is a selective kinase inhibitor of mesenchymal epithelial transition factor/hepatocyte growth factor receptor with known off‐target inhibitory activity against the phosphodiesterase (PDE) family. Rats given repeated oral doses of PF‐04254644 developed a mild to moderate myocardial degeneration accompanied by sustained increase in heart rate and contractility. Investigative studies were conducted to delineate the mechanisms of toxicity. Microarray analysis of Sprague–Dawley rat hearts in a 6 day repeat dose study with PF‐04254644 or milrinone, a selective PDE3 inhibitor, revealed similar perturbation of the cyclic adenosine monophosphate (c‐AMP) pathway. PDE inhibition and activation of c‐AMP were further substantiated using PDE3B immunofluorescence staining and through a c‐AMP response element reporter gene assay. The intracellular calcium and oxidative stress signaling pathways were more perturbed by treatment with PF‐04254644 than milrinone. The rat cardiomyocytes calcium assay found a dose‐dependent increase in intracellular calcium with PF‐04254644 treatment. These data suggest that cardiotoxicity of PF‐04254644 was probably due to activation of c‐AMP signaling, and possibly subsequent disruption of intracellular calcium and oxidative stress signaling pathways. The greater response with PF‐04254644 as compared with milrinone in gene expression and micro‐ and ultrastructural changes is probably due to the broader panel of PDEs inhibition. Copyright © 2012 John Wiley & Sons, Ltd.
In vivo comet assay of multi‐walled carbon nanotubes using lung cells of rats intratracheally instilled
Authors: Ema Makoto , Masumori Shoji , Kobayashi Norihiro , Naya Masato , Endoh Shigehisa , Maru Junko , Hosoi Masayo , Uno Fuyumi , Nakajima Madoka , Hayashi Makoto , Nakanishi Junko
Published: August 2012

The genotoxicity of multi‐walled carbon nanotubes (MWCNTs) was evaluated in vivo with comet assays using the lung cells of rats given MWCNTs. The MWCNTs were intratracheally instilled as a single dose at 0.2 or 1.0 mg kg–1 or a repeated dose at 0.04 or 0.2 mg kg–1, once a week for 5 weeks, to male rats. The rats were sacrificed 3 or 24 h after the single instillation and were sacrificed 3 h after the last instillation in the repeated instillation groups. Histopathological examinations of the lungs revealed that MWCNTs caused inflammatory changes including the infiltration of macrophages and neutrophils after a single instillation and repeated instillation at both doses. In comet assays using rat lung cells, no changes in % Tail DNA were found in any group given MWCNTs. These findings indicate that MWCNTs do not have the potential to cause DNA damage in comet assays using the lung cells of rats given MWCNTs at doses causing inflammatory responses. Copyright © 2012 John Wiley & Sons, Ltd.
Configuration space partitioning and matrix buildup scaling for the vibrational configuration interaction method
Authors: Samsonyuk Andriy , Scheurer Christoph
Published: August 2012

The accurate computation of anharmonic vibrational states for medium to large molecules is a requirement for the detailed understanding of nonlinear multidimensional infrared spectra and the dynamical information encoded in them. The vibrational configuration interaction (VCI) method constitutes a particularly promising tool in this respect. It is generally hampered though by its unfavorable scaling with respect to system size. We analyze the scaling behavior of several well‐known as well as some new approximate VCI schemes in detail, which are complementary to the class of configuration selection schemes developed recently. We find that the combination of a configuration space partitioning, possibly based on configuration selection, with energetic thresholding and resonance screening provides an efficient scheme for the reduction of computational effort involved in VCI calculations while at the same time maintaining sufficient accuracy for the vibrational energies. © 2012 Wiley Periodicals, Inc.
Macromonomers as Well‐Defined Building Blocks in the Synthesis of Hybrid Octafunctional Star‐Shaped Poly(ethylene oxide)s
Authors: Pozza Gladys M.‐E. , Harris Hassan , Barthel Markus J. , Vitz Jürgen , Schubert Ulrich S. , Lutz Pierre J.
Published: August 2012

The present work addresses the synthesis and the molecular and structural characterization of soluble macromolecular architectures based on functional poly(ethylene oxide) (PEO)s and octafunctional silsesquioxanes. The synthesis of a series of functional PEOs by deactivation, decorated with allyl groups at one chain‐end, was considered first. PEO star‐shaped polymers were prepared by coupling via hydrosilylation of ω‐allyl PEOs with octakis(hydridodimethylsiloxy)octasilsesquioxane (HMe2SiOSiO1.5)8 (Q8M8H), in the presence of a “Speier” catalyst. The products were characterized by SEC, 1H NMR spectroscopy, light scattering, and MALDI–TOF MS to determine the molar masses and degree of functionalization. The star‐shaped PEOs (Q8M8PEO) could be isolated from the raw reaction product and characterized. A functionalization close to the theoretical value was obtained.
pH‐Responsive Double‐Hydrophilic Block Copolymers: Synthesis and Drug Delivery Application
Authors: Dai Xiao‐Hui , Hong Chun‐Yan , Pan Cai‐Yuan
Published: August 2012

A novel double‐hydrophilic block copolymer P(MEO2MA‐co‐OEGMA)‐b‐PAMA has been successfully synthesized by two‐step RAFT polymerization. Then, the amino groups of PAMA blocks in the copolymers react with 1‐pyrenecarboxaldehyde via a “Schiff‐base” reaction, and the resulting copolymers are self‐assembled to form spherical micelles in aqueous solution. Because the “Schiff‐base” linkage is pH sensitive, the release rate of pyrene depends upon the pH of solution. Complete release is achieved at pH 1, and the control release is much faster at pH 5.5 than that at pH 7.4. With progress of pyrene release, the micelles are disassembled gradually and disappeared completely at last. This double‐hydrophilic copolymer is a promising candidate of drug carrier for the aldehyde‐ containing hydrophobic drugs.
Plant Oil‐Based Long‐Chain C26 Monomers and Their Polymers
Authors: Vilela Carla , Silvestre Armando J. D. , Meier Michael A. R.
Published: August 2012

The self‐metathesis of erucic acid with ruthenium‐based catalysts, followed by the hydrogenation of the double bond, yielded 1,26‐hexacosanedioic acid (AA). Polycondensation of this biobased long‐chain α,ω‐dicarboxylic acid with hexacosane‐1,26‐diol (BB), generated from the former by reduction, yielded the polyester 26,26. Monomer AA was also polymerized with short‐chain alkanediols, namely dodecane‐1,12‐diol and butane‐1,4‐diol, generating polyesters 12,26 and 4,26, respectively. The properties of these aliphatic polyesters were investigated by various techniques, revealing high crystallinity, melting, and degradation temperatures, depending on the monomers used. These materials are an attractive alternative to fossil resource‐based polymeric materials.
Recent Progress in the Development of New Acetylenic Polymers
Authors: Hu Rongrong , Lam Jacky Wing Yip , Tang Ben Zhong
Published: August 2012

Acetylenic polymers are a group of specialty materials with novel properties. In this paper, recent progress in the development of functional acetylenic polymers is summarized. These polymers are synthesized through different polymerization approaches such as Sonogashira polycoupling, decarbonylative chloroarylation polyaddition, and polycyclotrimerization. Efforts in the development of new monomers and catalyst exploration as well as reaction optimization have lead to a large quantity of linear and hyperbranched polymers with high molecular weights and good processability. The polymer functionalization is realized by incorporating functional units into the monomer structures, which endow the resulting polymers with fascinating properties such as aggregation‐induced emission, optical nonlinearity, light refractivity, photosensitivity, photopatternability, redoxactivity, and magnetism.
Open‐chain unsaturated selanyl sulfides: stereochemical structure and stereochemical behavior of their 77Se–1H spin–spin coupling constants
Authors: Rusakov Yury Yu. , Krivdin Leonid B. , Penzik Maxim V. , Potapov Vladimir A. , Amosova Svetlana V.
Published: August 2012

Stereochemical structure of nine Z‐2‐(vinylsulfanyl)ethenylselanyl organyl sulfides has been investigated by means of experimental measurements and second‐order polarization propagator approach calculations of their 1H–1H, 13C–1H, and 77Se–1H spin–spin coupling constants together with a theoretical conformational analysis performed at the MP2/6‐311G** level. All nine compounds were shown to adopt the preferable skewed s‐cis conformation of their terminal vinylsulfanyl group, whereas the favorable rotational conformations with respect to the internal rotations around the C–S and C–Se bonds of the internal ethenyl group are both skewed s‐trans. Stereochemical trends of 77Se–1H spin–spin coupling constants originating in the geometry of their coupling pathways and the selenium lone pair effect were rationalized in terms of the natural J‐coupling analysis within the framework of the natural bond orbital approach. Copyright © 2012 John Wiley & Sons, Ltd.
Structural trends of 29Si–1H spin–spin coupling constants across double bond
Authors: Rusakov Yury Yu. , Krivdin Leonid B. , Nosova Valentina M. , Kisin Alexander V. , Lakhtin Valentin G.
Published: August 2012

The calculations of geminal and vicinal 29Si–1H spin–spin coupling constants across double bond in 15 alkenylmethylsilanes and alkenylchlorosilanes were carried out at the second‐order polarization propagator approach level in a good agreement with experiment. Two structural trends, namely, (i) the geometry of the coupling pathway and (ii) the effect of the electrowithdrawing substituent, have been interpreted in terms of the natural J‐coupling analysis within the framework of the natural bond orbital approach. Thus, the marked difference between cisoidal and transoidal 29Si–1H spin–spin coupling constants across double bond was accounted for the delocalization contributions including bonding and antibonding Si–C and C–H orbitals, whereas the chlorine effect was explained in terms of the steric contributions including bonding Si–Cl orbitals. Copyright © 2012 John Wiley & Sons, Ltd.
Suboptimal robust linear visual servoing for a delayed underactuated system
Authors: Benitez‐Morales A. , Santos Omar , Romero Hugo , Ramos‐Velasco Luis Enrique
Published: August 2012

In this contribution, a suboptimal robust control law for a specific class of underactuated delayed system is synthesized. The control strategy based on very well‐known results for delay‐dependent stability considers the time delay involved in the dynamical system, which affects to control signal. This contribution illustrates how the theoretical results can be used to improve the real‐time performance of the closed‐loop system considered. The delay is introduced into the control system by the vision module, due to the time required to perform the image treatment. In order to show the good performance of the control law proposed, real‐time experiments are developed by applying a visual servoing technique on the cart‐inverted pendulum system. Obtained results also illustrate how the conservativeness of theoretical results affects the performance of the closed‐loop system and the negative effects of delays in the control loop. Furthermore, a robust stability analysis is done to establish the robustness of control law with respect to the amount of delay presented in the system.Copyright © 2012 John Wiley & Sons, Ltd.
Preparative Isolation and Purification of Three Stilbene Glycosides from the Tibetan Medicinal Plant Rheum tanguticum Maxim. Ex Balf. by High‐speed Counter‐current Chromatography
Authors: Zhao Xiao‐Hui , Han Fa , Li Yu‐Lin , Yue Hui‐Lan
Published: August 2012

Introduction

Stilbene glycosides are the primary constituents of Rheum tanguticum Maxim. ex Balf., to which different bioactivities has been attributed, including: anti‐HIV, anti‐oxidant, anti‐tumour, anti‐malarial, and anti‐allergy activity. However, effective methods for the isolation and purification of stilbene glycosides, such as trans‐rhapontin, cis‐rhapontin and trans‐desoxyrhaponticin, from this herb are not currently available.

Objective

To develop an efficient method for the preparative isolation and purification of three stilbene glycosides from Rheum tanguticum Maxim. ex Balf. via high‐speed counter‐current chromatography (HSCCC).

Methods

A solvent system composed of chloroform:n‐butanol:methanol:water (4:1:3:2, v/v/v/v) was developed for the separation. The upper phase was used as the stationary phase, and the lower phase was used as the mobile phase. The flow rate was 1.8 mL/min. The apparatus was controlled at 800 rpm and 25 °C, and the effluent was monitored at 280 nm. Chemical constituents were analysed by high‐performance liquid chromatography (HPLC), and their structures were identified by 1 H‐ and 13C‐NMR.

Results

Under the optimised conditions, 25.5 mg trans‐rhapontin, 16.0 mg cis‐rhapontin and 20.5 mg trans‐desoxyrhaponticin were separated from 80 mg crude sample; the isolates had purities of 99.6, 97.2 and 99.2%, respectively.

Conclusion

A simple and efficient HSCCC method has been optimised for the preparative separation of stilbene glycosides from Rheum tanguticum Maxim. ex Balf. Copyright © 2012 John Wiley & Sons, Ltd.
Proteomic analysis of cerebrospinal fluid before and after intrathecal injection of steroid into patients with postherpetic pain
Authors: Lu Jingshan , Katano Tayo , Nishimura Wataru , Fujiwara Shunsuke , Miyazaki Shinichiro , Okasaki Issay , Aritake Kosuke , Urade Yoshihiro , Minami Toshiaki , Ito Seiji
Published: August 2012

Postherpetic neuralgia (PHN) is the most frequent complication of herpes zoster, and the risk of it increases with age. By comparing proteomes of the cerebrospinal fluid (CSF) before and after the treatment, it may be possible to identify proteins that play a role in PHN and to predict responses to various treatments. To address this issue, we enrolled eight outpatients with PHN over 55 years of age and treated them with intrathecal methylprednisolone and lidocaine four times every week, collecting CSF samples before the treatment at each visit. We used 2D DIGE to investigate differentially expressed proteins in the CSF before and after repetitive treatments individually. Of 145 differentially expressed spots, the levels of nine proteins were decreased by the treatment including lipocalin‐type prostaglandin D synthase (L‐PGDS), and five were increased by it. The time course of alterations in the L‐PGDS concentration in the CSF of each patient, detected by a pairwise and sandwich ELISA by SPR constructed here was well correlated with that by 1DE Western blots with anti‐L‐PGDS antibody, but was not related with that of the pain relief. The present study demonstrates that the real‐time ELISA was precise and sensitive enough to measure L‐PGDS in the CSF and that the steroid treatment decreased the L‐PGDS concentration in CSF.
Evaluation of SDS depletion using an affinity spin column and IMS‐MS detection
Authors: Hengel Shawna M. , Floyd Erica , Baker Erin S. , Zhao Rui , Wu Si , Paša‐Tolić Ljiljana
Published: August 2012

While the use of detergents is necessary for a variety of protein isolation preparation protocols, they are not compatible with mass spectral analysis due to ion suppression and adduct formation. This manuscript describes optimization of detergent removal, using commercially available SDS depletion spin columns containing an affinity resin, providing for both increased protein recovery and thorough SDS removal. Ion mobility spectrometry coupled with mass spectrometry (IMS‐MS) allowed for a concurrent analysis of both analyte and detergent. In the case of both proteins and peptides, higher detergent concentrations than previously reported provided an increase of sample recovery; however there was a limit as SDS was detected by IMS‐MS at higher levels of SDS indicating incomplete detergent depletion. The results also suggest that optimal conditions for SDS removal are dependent on the sample concentration. Overall, this study provides a useful guide for proteomic studies where SDS is required for efficient sample preparation.
Correlation between TGF‐β1 expression and proteomic profiling induced by severe acute respiratory syndrome coronavirus papain‐like protease
Authors: Li Shih‐Wen , Yang Tsuey‐Ching , Wan Lei , Lin Ying‐Ju , Tsai Fuu‐Jen , Lai Chien‐Chen , Lin Cheng‐Wen
Published: August 2012

Severe acute respiratory syndrome (SARS) coronavirus (SARS‐CoV) papain‐like protease (PLpro), a deubiquitinating enzyme, demonstrates inactivation of interferon (IFN) regulatory factor 3 and NF‐κB, reduction of IFN induction, and suppression of type I IFN signaling pathway. This study investigates cytokine expression and proteomic change induced by SARS‐CoV PLpro in human promonocyte cells. PLpro significantly increased TGF‐β1 mRNA expression (greater than fourfold) and protein production (greater than threefold). Proteomic analysis, Western blot, and quantitative real‐time PCR assays indicated PLpro upregulating TGF‐β1‐associated genes: HSP27, protein disulfide isomerase A3 precursor, glial fibrillary acidic protein, vimentin, retinal dehydrogenase 2, and glutathione transferase omega‐1. PLpro‐activated ubiquitin proteasome pathway via upregulation of ubiquitin‐conjugating enzyme E2–25k and proteasome subunit alpha type 5. Proteasome inhibitor MG‐132 significantly reduced expression of TGF‐β1 and vimentin. PLpro upregulated HSP27, linking with activation of p38 MAPK and ERK1/2 signaling. Treatment with SB203580 and U0126 reduced PLpro‐induced expression of TGF‐β1, vimentin, and type I collagen. Results point to SARS‐CoV PLpro triggering TGF‐β1 production via ubiquitin proteasome, p38 MAPK, and ERK1/2‐mediated signaling.
Proteomic analysis of ganglioside‐associated membrane molecules: Substantial basis for molecular clustering
Authors: Hashimoto Noboru , Hamamura Kazunori , Kotani Norihiro , Furukawa Keiko , Kaneko Kei , Honke Koichi , Furukawa Koichi
Published: August 2012

Ganglioside GD3 is specifically expressed in human melanomas, and plays a role in the enhancement of malignant phenotypes of melanoma cells. To analyze the mechanisms by which GD3 enhances malignant properties and signals in melanomas, it is essential to clarify how GD3 interacts with membrane molecules on the cell membrane. In this study, we performed proteomics analysis of glycolipid‐enriched microdomains (GEM) with current sucrose density gradient ultracentrifugation of Triton X‐100 extracts and MS. We also examined GD3‐associated molecules using enzyme‐mediated activation of radical sources (EMARS) reaction combined with MS. Comparison of molecules identified as residents in GEM/rafts and those detected by EMARS reaction using an anti‐GD3 antibody revealed that a relatively low number of molecules is recruited around GD3, while a number of membrane and secreted molecules was defined in GEM/rafts. These results suggested that EMARS reaction is useful to identify actually interacting molecules with gangliosides such as GD3 on the cell membrane, and many other microdomains than GD3‐associating rafts exist. Representative examples of GD3‐associated molecules such as neogenin and MCAM were shown.
Measurement of distress in Chinese inpatients with lymphoma
Authors: Wang Yisi , Zou Liqun , Jiang Ming , Wei Yuquan , Jiang Yu
Published: August 2012

Purpose

The aim of this study was to assess the levels and sources of distress in patients with lymphoma. This study also focused on the influence of factors of the level of distress and the cutoff score using the Distress Thermometer (DT) relative to the Hospital Anxiety and Depression Scale (HADS).

Method

DT and HADS were used to estimate the psychological status of 323 eligible lymphoma patients. The DT was evaluated against the HADS for its sensitivity and specificity.

Results

One hundred and ninety‐three (59.7%) lymphoma patients experienced overall distress on the HADS, with 137 (42.4%) experiencing anxiety and 114 (35.3%) suffering from depression. There were 199 (61.6%) and 163 (50.5%) patients with distress score ≥4 and ≥5, respectively. DT was significantly correlated with the HADS‐total (T) (r = 0.820, p < 0.001), HADS‐depression (D) (r = 0.763, p < 0.001), and HADS‐anxiety (A) (r = 0.738, p < 0.001). The consistency of the DT and HADS was favorable (coherence index = 0.6030, p < 0.01) when the cutoff score was 5 for the DT. Referring to the cutoff of 15 on HADS, 5 on DT yielded optimal specificity (0.869, p < 0.001) and sensitivity (0.756, p < 0.001). In multiple logistic regression analysis, patients with ‘B symptoms’ were more likely to have a distress score ≥5 [OR = 4.512, p < 0.05, 95% CI 1.953–10.467].

Conclusion

DT is efficacious for screening for anxiety and depression in lymphoma patients. Copyright © 2012 John Wiley & Sons, Ltd.
Absence of in vitro innate immunomodulation by insect‐derived short proline‐rich antimicrobial peptides points to direct antibacterial action in vivo
Authors: Fritsche Stefanie , Knappe Daniel , Berthold Nicole , von Buttlar Heiner , Hoffmann Ralf , Alber Gottfried
Published: August 2012

Some antimicrobial peptides (AMPs) have been described to exert immunomodulatory effects, which may contribute to their in vivo antibacterial activity. Very recently, we could show that novel oncocin and apidaecin derivatives are potently antibacterially active in vivo. Therefore, we studied oncocin and apidaecin derivatives for their effects on murine dendritic cells (DC) and macrophages and compared them with well‐known immunomodulatory activities of murine cathelicidin‐related antimicrobial peptide (CRAMP). To characterize the immunomodulatory activity of the peptides on key cells of the innate immune system, we stimulated murine DC and macrophages with the oncocin and apidaecin derivatives alone, or in combination with lipopolysaccharide (LPS). We analyzed the secretion of pro‐inflammatory cytokines, the expression of surface activation markers, and the chemotactic activity of the AMPs. In contrast to LPS, none of the oncocin and apidaecin derivatives alone has an influence on cytokine or surface marker expression by DC and macrophages. Furthermore, the tested oncocin and apidaecin derivatives do not modulate the immune response after LPS stimulation, whereas CRAMP shows a reduction of the LPS‐mediated immune response as expected. All peptides tested are not chemotactic for DC. Together, lack of in vitro immunomodulatory effects by oncocin and apidaecin derivatives on key cells of the innate murine immune system suggests that their potent in vivo antibacterial activity relies on a direct antibacterial effect. This will simplify further pharmaceutical investigation and development of insect peptides as therapeutic compounds against bacterial infections. Copyright © 2012 European Peptide Society and John Wiley & Sons, Ltd.
Diamond as a nanomedical agent for versatile applications in drug delivery, imaging, and sensing
Authors: Man Han B. , Ho Dean
Published: August 2012

A spectrum of materials has been explored as potential platforms for nanomedicine in the areas of drug delivery, imaging, and diagnostics/sensing. Depending upon the application required, the therapeutic compound being delivered, or the imaging agent being modified, certain nanoparticulate materials offer specific advantages that may uniquely enhance efficiency. Among the classes of particles being investigated, diamond‐based platforms have emerged as promising vehicles for drug delivery and imaging following several recent studies that demonstrate their ability to enhance therapeutic efficacy, particularly for anthracyclines, mediate markedly improved magnetic resonance imaging contrast and photostable fluorescence, possess scalable processing parameters, and exhibit biocompatibility, among many other important attributes. More specifically, detonation NDs have faceted surfaces that can mediate potent interactions with surrounding water molecules or therapeutic compounds. This attribute can mitigate premature drug release to prevent major side effects such as myelosuppression, while water molecule recruitment can increase the relaxivity of covalently conjugated gadolinium. These properties of NDs and diamond‐based devices will be discussed in this article, with a focus on therapeutic delivery in addition to insight on their use in imaging, devices, implants/coatings, and biocompatibility. Key areas of potential, where advances in biology and medicine can be realized through the continued development of this platform as well as requisite future studies, will also be highlighted.
From porous to dense thin ZnO films through reactive DC sputter deposition onto Si (100) substrates
Authors: Borysiewicz Michał A. , Dynowska Elżbieta , Kolkovsky Valery , Dyczewski Jan , Wielgus Maciej , Kamińska Eliana , Piotrowska Anna
Published: August 2012

Thin polycrystalline ZnO films are deposited onto Si (100) substrates by means of DC reactive sputter deposition from a Zn target in an argon–oxygen mixture. The influences of the oxygen content in the mixture and of the total gas pressure in the reactor during deposition as well as of applying postgrowth annealing in an oxygen flow at elevated temperatures on the structural, chemical, and electrical properties of the obtained films are discussed. Three types of thin‐film structures were obtained: a porous polycrystalline Zn layer, a porous polycrystalline ZnO layer and a dense ZnO film. The porous Zn layer grew at oxygen content less than 33% and upon annealing in an oxygen flow at 400, 600, and 800 °C transformed to porous polycrystalline ZnO films. For oxygen contents ≥33% the obtained films were dense and polycrystalline with a 00.2 dominating orientation. X‐ray diffraction (XRD), scanning electron microscopy (SEM), Rutherford backscattering spectroscopy (RBS), and Hall effect measurements were applied to characterize the obtained films.
Drift mobility of thermalized and highly energetic holes in thin layers of amorphous dielectric SiC
Authors: Sielski Jan , Jeszka Jeremiasz K.
Published: August 2012

The development of new technology in the electronics industry requires new dielectric materials. It is also important to understand the charge‐carrier transport mechanism in these materials. We examined the hole drift mobility in amorphous SiC dielectric thin films using the time‐of‐flight (TOF) method. Charge carriers were generated using an electron gun. The generated holes gave a dispersive TOF signal and the mobility was low. For electric field strengths above 4 × 105 V cm−1 the drift mobility shows a very strong dependence on the electric field and a weak temperature dependence (transport of “high‐energy” charge carriers). At lower electric fields and for thermalized charge carriers the mobility is practically field independent and thermally activated. The observed phenomenon was attributed to the changes in the effective energy of the generated carriers moving in the high electric fields and consequently in the density of localized states taking part in the transport.
Optical switching patterns using electrospun nanofiber array
Authors: Kim Bumjoo , Cho Seong J. , An Taechang , Ryu Hyobong , Lim Hoon , Lim Geunbae
Published: August 2012

This is a report on optical switching patterns textured by electrospun nanofibers according to the direction of the incident light. The effect of fiber size is also explained. Depending on the direction of the incident light, there should be two distinct reflective behaviors on the surfaces of the nanofibers: diffuse and specular reflections. The mechanism for this critical phenomenon is explained in terms of the cylindrical geometry of the fiber surface, and the “on–off” reflective behavior can be maximized when the diameters of the fibers are quite small, such as nanofibers.

magnified image

Switching the patterns of a nanofiber array according to the direction of light: north and east, respectively (scale bar = 1 mm).

(© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The race for interferon‐free HCV therapies: a snapshot by the spring of 2012
Authors: De Clercq Erik
Published: August 2012

After a decade of having been the standard of care (SOC) for the treatment of chronic HCV infection, PEGylated IFN (combined with ribavirin) is now at the verge of being complemented and then replaced by a combination of new DAAs and even some compounds interacting with host cell factors. Principal targets for the direct‐acting antivirals (DAAs) are the protease NS3/4A, the protein NS5A, and the RNA‐dependent RNA polymerase NS5B, which offers at least two target sites, the catalytic domain for nucleos(t)ides and several non‐catalytic (allosteric) domains for the non‐nucleoside type of NS5B inhibitors. Two PIs have already been approved, but many more NS3/4A, NS5A, and NS5B (up to 40!) inhibitors are in (pre)clinical development. The abundance of candidate anti‐HCV drugs will, on the one hand, speed up their development but, on the other hand, complicate the choice of the most appropriate drug combination(s). Copyright © 2012 John Wiley & Sons, Ltd.
Distributed control of nonlinear diffusion systems by input–output linearization
Authors: Maidi Ahmed , Corriou Jean‐Pierre
Published: August 2012

This paper addresses the distributed control by input–output linearization of a nonlinear diffusion equation that describes a particular but important class of distributed parameter systems. Both manipulated and controlled variables are assumed to be distributed in space. The control law is designed using the concept of characteristic index from geometric control by using directly the PDE model without any approximation or reduction. The main idea consists in the control design in assuming an equivalent linear diffusion equation obtained by use of the Cole–Hopf transformation. This framework helps to demonstrate the closed‐loop stability using some concepts from the powerful semigroup theory. The performance of the proposed controller is successfully tested, through simulation, by considering a nonlinear heat conduction problem concerning the control of the temperature of a steel plate modeled by a nonlinear heat equation with Dirichlet boundary conditions. Copyright © 2012 John Wiley & Sons, Ltd.
Cooperative control with distributed gain adaptation and connectivity estimation for directed networks
Authors: Qu Zhihua , Li Chaoyong , Lewis Frank
Published: August 2012

This paper addresses the problem of how to achieve superior performance by adaptively and distributively adjusting control gains of a cooperative control system. It is shown that according to distributed observations of changing network topologies and on the basis of online estimation of network connectivity, cooperative controls with adaptive gains can be synthesized to making the time derivative of the cooperative control Lyapunov function more negative and hence to improve stability and convergence of the overall system. For undirected networks, the proposed adaptive design reduces to improving the Fiedler eigenvalue (algebraic connectivity) as well as other eigenvalues. On the other hand, connectivity of a directed network is characterized by the property of the first left eigenvector(s) associated with its dominant eigenvalue, and in this paper, a distributed high‐gain observer design is proposed for each of the networked systems to utilize the same communication network among the systems. It is shown that even in the presence of transmission delays, the distributed estimators converge fast to the first left eigenvector(s) of the network. In addition, the expected consensus value(s) of the overall cooperative system under control is also estimated in a distributive manner. Rigorous analysis is carried out on estimation convergence and observer gain selection. It is shown that the proposed estimation and adaptive control designs are fully distributed, have guaranteed performance for all possible varying topologies as long as their dwelling times are bounded away from zero, and are robust with respect to excessively fast topology changes. Simulation results are included to demonstrate effectiveness of the proposed estimation and control schemes. Copyright © 2012 John Wiley & Sons, Ltd.
Constrained control Lyapunov function based model predictive control design
Authors: Mahmood Maaz , Mhaskar Prashant
Published: August 2012

This work considers linear systems with input constraints with the objective of designing a controller that guarantees stability from all initial conditions in the null‐controllable region (the set of initial conditions from where the system can be stabilized). To this end, a recently developed procedure for construction of constrained control Lyapunov functions is utilized within a Lyapunov‐based model predictive controller coupled with an auxiliary control design to achieve stabilization from all initial conditions in the null‐controllable region. Illustrative simulation results as well as an application to a nonlinear chemical process example is presented to demonstrate the efficacy of the results.Copyright © 2012 John Wiley & Sons, Ltd.
UNCERTAINTY IN PREDICTING THE FISH‐RESPONSE TO TWO‐DIMENSIONAL HABITAT MODELING USING FIELD DATA
Authors: Boavida I. , Santos J. M. , Katopodis C. , Ferreira M. T. , Pinheiro A.
Published: August 2012

Both water managers and researchers have the same goal when it comes to fish conservation, namely, to sustain, to improve or to restore aquatic habitat. To this aim, two‐dimensional (2D) hydrodynamic models have been widely used in aquatic habitat studies because they simulate flow with high accuracy and can predict habitat dynamics. The River2D model is able to integrate the habitat suitability curves for fish life stages with the simulated depth and velocity fields and the riverbed characteristics of substrate and cover, thereby estimating the corresponding weighted usable area, and thus predicting the potential distribution of fish species in the river. However, little is known about the in situ variability associated with such predictions both for hydraulic and biological data, whereas ecological responses are known to be driven by variability. Moreover, when calculating habitat availability, differences can be found by considering in the weighted usable area formulation substrate or cover or even both. To test the level of predictive accuracy of hydraulic and biological simulations, we modelled the habitat use by two fish species, the Iberian barbel Luciobarbus bocagei and the Iberian straight‐mouth nase Pseudochondrostoma polylepis, according to their requirements for depth, velocity, substrate and cover and then compared measured and simulated hydraulic and biological outcomes using the River2D model. Results indicate that 2D simulation depends on data collection, especially the density and location of bed topography points. Substantial differences were found in the biological responses. Results may differ when choosing different habitat availability variables. Similarly, habitat use may also be influenced by other biotic and abiotic interactions occurring in ecosystems, and restoration planning should be aware of such variability. Copyright © 2012 John Wiley & Sons, Ltd.
STREAM HABITAT MODELLING FOR CONSERVING A THREATENED HEADWATER FISH IN THE UPPER CUMBERLAND RIVER, KENTUCKY
Authors: Liang L. , Fei S. , Ripy J. B. , Blandford B. L. , Grossardt T.
Published: August 2012

The conservation of stream biodiversity requires more explicit knowledge on the distribution of aquatic species within the context of their specific environmental settings and stresses. Although species distribution models (SDMs) have been widely used for organisms occupying contiguous spatial extents, the implementation of SDMs in relatively complex and segmented riverine networks is still at its early stage. In this study, we explicitly modelled the headwater stream habitat for the threatened blackside dace (Phoxinus cumberlandensis) endemic to the upper Cumberland River, Kentucky, USA. An occurrence record data set, along with variables describing stream properties and land use impacts, was used to predict the fish habitat suitability at the stream segment level. An approach combining geographic information systems and the maximum entropy species distribution modelling (MaxEnt) was adopted. Results demonstrated that natural conditions and land use disturbances, respectively, form the primary and secondary environmental constraints on the species' habitat. We generated regional‐scale management‐friendly maps showing subwatershed habitat suitability and locations of the clustered suitable habitats (hotspots) and thus set an example for spatially explicit management of threatened and endangered riverine species. This study demonstrates the usefulness of SDMs for stream network–based environments in the facilitation of biogeographic conservation efforts and studies. Copyright © 2012 John Wiley & Sons, Ltd.
Design and FESEM/EDX investigation of functional magnetic nanocomposite particles
Authors: Behrens Silke , Dinjus Eckhard , Essig Sarah , Gorschinski Angelika , Habicht Wilhelm
Published: August 2012

Recently, magnetic nanoparticles and nanocomposite microspheres have attracted great interest for biomedical and technical application. Magnetic metal nanoparticles are of special interest due to their beneficial, size‐dependent magnetic properties. Superparamagnetic metal nanoparticles and mesoscale nanocomposite particles (viz. Co nanoparticles, Co@SiO2, and Co@SiO2@TiO2 particles) were obtained by a three‐step synthesis, involving consecutive steps of thermolysis and sol–gel procedures. A high‐resolution Schottky‐type field emission scanning electron microscope (FESEM) equipped with an energy dispersive X‐ray spectrometer was used to characterize intermediate and final products at the successive stages of synthesis. The samples were deposited on carbon‐coated transmission electron microscopy (TEM) grids (thin film technique) which afforded enhanced specimen contrast and reduced X‐ray background contribution in microanalysis. The FESEM was equipped with a special mounting device for these grids with an appropriate detector beneath. By this method, the samples, covering sizes from the nanometer to micron scale, could be characterized and analyzed by several imaging modes, viz. with standard SE and BSE detection mode and supplementary with low‐voltage scanning transmission mode (STEM‐in‐SEM) and fundamental information about particle size, morphology, and elemental distribution was obtained. Copyright © 2012 John Wiley & Sons, Ltd.