bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use of chitosan for removal of naphthols through tyrosinase‐catalyzed quinone oxidation
Authors: Kimura Yuji , Kashiwada Ayumi , Matsuda Kiyomi , Yamada Kazunori 
Published: February 2012

AbstractIn this study, the combined use of chitosan and mushroom tyrosinase was applied to remove 1‐naphthol and 2‐naphthol from aqueous solutions. In particular, the process parameters, such as the pH value, temperature, and enzyme dose, were discussed for tyrosinase‐catalyzed quinone oxidation of 1‐naphthol. The optimum conditions of enzymatic quinone oxidation of 1‐naphthol were determined to be pH 8.0 and 40°C. Under the optimum conditions, quinone oxidation of 1‐naphthol increased with an increase in the enzyme dose. Quinone derivatives enzymatically generated were chemisorbed on chitosan bead sand. The initial velocity of enzymatic quinone oxidation increased with an increase in the amount of added chitosan beads, since unfavorable interactions between quinone derivatives and tyrosinase in the solutions were restrained by quinone adsorption. 1‐Naphthol was completely removed for 8 h by quinone adsorption on chitosan beads (0.10 cm3/cm3) at 20 U/cm3. The removal time was shortened by increasing the enzyme dose or the amount of added chitosan beads. 2‐Naphthol was also completely removed by increasing the enzyme concentration and reaction time, since enzymatic quinone oxidation of 2‐naphthol was much slower than that of 1‐naphthol. The above results reveal that the procedure constructed in this study was an effective technique to remove naphthols. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Electrochemical DNA biosensor based on IL‐modified MWNTs electrode prepared by radiation‐induced graft polymerization
Authors: Chung Da‐Jung , Whittaker Andrew K. , Choi Seong‐Ho 
Published: February 2012

AbstractElectrochemical DNA (E‐DNA) biosensors were fabricated by the physical immobilization of probe DNA, 5′‐GGA GCT GCT GGC ATT ATT GAA‐3′, on ionic‐liquid‐multiwalled carbon nanotubes (IL‐MWNTs) modified with indium tin oxide (ITO) electrodes to detect Salmonella typhi (S. typhi). IL‐MWNTs were prepared by the introduction of 1‐butylimidazole bromide onto an epoxy group on poly(GMA)‐grafted MWNTs, which were synthesized by radiation‐induced graft polymerization of glycidyl methacrylate (GMA) onto MWNTs in aqueous solution. Subsequently, IL‐MWNTs were coated onto the ITO electrode surface, and then the physical immobilization of the probe DNA performed in probe DNA solution at room temperature for 1 h. The IL‐MWNTs were characterized by elemental analysis, XPS, and TGA. The electron transfer resistance (Ret) of the E‐DNA biosensor was evaluated after hybridization of the probe DNA and target DNA using electrochemical impedance spectroscopy. The Ret increased after the hybridization of probe DNA and target DNA. The DNA used was complementary DNA: 5′‐TTC AAT AAT GCC AGC AGC TCC‐3′, single‐base mismatch DNA: 5′‐TTC AAT AAT GGC AGC AGC TCC‐3′ and three‐base mismatch DNA: 5′‐TTC ATT AAT GGC AGC ACG TCC‐3′. The dynamic detection range for the sequence‐specific DNA of target DNA was from 1.0 × 10−13 to 1.0 × 10−10 mol L−1 with a regression equation Ret (Ω) = 18.6 C + 128 and regression coefficient (γ) of 0.996. The detection limit was determined to be 3.1 × 10−14 mol L−1. The results demonstrated that the sensitivity of this impedance‐based DNA sensor was sufficient for the target DNA sequence detection. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Multilayer biopolymer membranes containing copper for antibacterial applications
Authors: de Paiva Rafael G. , de Moraes Mariana A. , de Godoi Fernanda C. , Beppu Marisa M. 
Published: February 2012

AbstractChitosan/alginate multilayer dense membranes, with micrometric thicknesses, were produced by casting the solution of each polymer alternately on a Petri dish. Copper ions were also incorporated into these membranes, which were then characterized with regard to morphology, chemical and crystallographic structures, ions diffusivity, and bacteriostatic properties. Results indicate that the casting approach for multilayers production was successful, since the membranes produced were formed by organized and alternated polymer layers. The pH dependence of the metal adsorption resulted in a higher concentration of the copper in the alginate layers, as shown by SEM‐EDS (scanning electron microscopy ‐ energy dispersive X‐ray spectroscopy) analysis. Fourier transformed infrared spectroscopy confirmed the Coulombic interaction between the chitosan amino groups and sodium alginate carboxyl groups. The copper ions were distributed homogeneously, without the formation of clusters, and were bound mainly to oxygen and nitrogen atoms located on the alginate and chitosan functional groups, respectively, according to extended X‐ray absorption fine structure (EXAFS) results. The antibacterial properties of this membrane indicate that this material may hold promise for numerous applications, such as for water treatment or antibacterial functional coatings with controlled release. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Glycerol citrate polyesters produced through heating without catalysis
Authors: Tisserat Brent , O'kuru Rogers Harry , Hwang HongSik , Mohamed Abdellatif A. , Holser Ronald 
Published: February 2012

AbstractThe influence of various heating methods without catalysis to prepare polyesters from citric acid : glycerol blends were studied. In the presence of short‐term microwave treatments, i.e., 60 s at 1200 W, blends of glycerol and citric acid invariably formed solid amorphous polyesters. Fourier transform infrared spectroscopy showed that citric acid and glycerol blends can form highly stable polymers composed of ester bonds. The glycerol citrate polyester polymers exhibited the least degradation in water, more in acid solutions (0.1–1.0M HCl), and the most deterioration in strong alkaline solutions (0.1–1.0M NaOH) after 72 h soakings. Polyesters of glycerol and citric acid were studied with differential scanning calorimetry and thermal gravimetric analysis. The polyesters were found to be thermally stable (up to 313°C). © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Separation of CO2/N2 by Means of a Carbon Membrane
Authors: Wall Y. , Braun G. , Kaltenborn N. , Voigt I. , Brunner G. 
Published: February 2012

AbstractThe permeation and separation performance of an ultramicroporous carbon membrane for separation of CO2/N2 mixtures were investigated. The experiments were conducted using the steady‐state measurement method with pure gases (dead‐end mode) and a CO2/N2 gas mixture (20/80 mol.‐%) (cross‐flow mode) in the temperature range from 293 K to 363 K and at feed pressures of up to 1.4 MPa and atmospheric pressure on the permeate side. The membrane exhibited a selectivity of about 25 and permeability of about 500 Barrer for CO2 in the mixture with N2. The single‐gas measurements do not reflect the membrane performance correctly. An adsorption‐selective effect is assumed to be the main separation mechanism. Moreover, membrane‐aging effects causing blocking due to pore constrictions through adsorption were observed. These pore constrictions lower the permeability, but they raise the selectivity. Operation at high temperatures leads to a reduction of aging effects.
Acceleration of option pricing technique on graphics processing units
Authors: Zhang Bowen , Oosterlee Cornelis W. 
Published: February 2012

SUMMARYThe acceleration of an option pricing technique based on Fourier cosine expansions on the graphics processing unit (GPU) is reported. European options, in particular with multiple strikes, and Bermudan options will be discussed. The influence of the number of terms in the Fourier cosine series expansion, the number of strikes, as well as the number of exercise dates for Bermudan options is explored. We also give details about the different ways of implementing on a GPU. Numerical examples include asset price processes on the basis of a Lévy process of infinite activity and the stochastic volatility Heston model. Furthermore, we discuss the issue of precision on the present GPU systems. Copyright © 2012 John Wiley & Sons, Ltd.
Are you Talking to us? How Subnational Governments Respond to Global Sustainable Development Governance
Authors: Happaerts Sander 
Published: February 2012

ABSTRACTSubnational governments (such as provinces, states or regions) are largely ignored in international policy documents on sustainable development, and they are not recognized in multilateral decision‐making. Nevertheless, many subnational governments have launched sustainable development policies. This article examines to what extent they take global sustainable development governance into account when doing so. The theoretical framework presents two mechanisms of international influence, building mostly upon the policy convergence literature. That framework is then applied on a comparative policy analysis of five subnational governments: North Holland (the Netherlands), North Rhine‐Westphalia (Germany), Wallonia (Belgium), Flanders (Belgium) and Quebec (Canada). The findings show that subnational governments with a distinct territorial identity react differently on international trends from other subnational governments. Flanders and Quebec, which have such an identity, follow the rules and decision‐making procedures of the international sustainable development regime, and they translate the norms and principles into their policies. The article also finds that the influence of international policies is determined by the active participation of subnational governments in multilateral decision‐making. Finally, it is argued that the legitimacy pressures exerted by international organizations on lower‐level governments to adopt certain policies have a varying impact on subnational governments dependent on their domestic context. Copyright © 2012 John Wiley & Sons, Ltd and ERP Environment.
Pompon‐Like MnF2 Nanostructures from a Single‐Source Precursor through Atmospheric Pressure Chemical Vapor Deposition
Authors: Malandrino Graziella , Toro Roberta G. , Catalano Maria R. , Fragalà Maria E. , Rossi Patrizia , Paoli Paola 
Published: February 2012

AbstractMnF2 nanorod assemblies in a pompon‐like fashion were synthesized by using a new complex, Mn(hfa)2·tmeda [(Hhfa = 1,1,1,5,5,5‐hexafluoro‐2,4‐pentandione, tmeda = N,N,N′,N′‐tetramethylethylenediamine)]. The complex was synthesized in a single‐step reaction, and single‐crystal X‐ray diffraction studies provide evidence of a mononuclear structure. The thermal analyses have shown that the complex is thermally stable and can be evaporated to leave less than 2 % residue at atmospheric pressure. On the basis of its thermal properties, it has been successfully applied to the atmospheric pressure metalorganic chemical vapor deposition (AP‐MOCVD) of MnF2 nanostructures.
Carbon Black‐Modified Screen‐Printed Electrodes as Electroanalytical Tools
Authors: Arduini Fabiana , Di Nardo Fabio , Amine Aziz , Micheli Laura , Palleschi Giuseppe , Moscone Danila 
Published: February 2012

AbstractIn this paper screen‐printed electrodes (SPEs) bulk modified with carbon black (CB) or with CB dispersion in DMF:water were developed and characterized. We have demonstrated by cyclic voltammetry, SEM and electrochemical impedance spectroscopy that an increase of CB amount on the working electrode surface increases the electrochemical performances of CB‐SPE. The CB‐SPE was tested with ferricyanide, epinephrine, benzoquinone and H2O2 demonstrating in any case an enhancement of electrochemical activity. For H2O2 amperometric detection, a sensitivity of 241.4±5.7 mA M−1 cm−2 and 1.46±0.06 mA M−1 cm−2 was obtained, respectively, for CB‐SPE and bare SPE.
Electrospun Nonwoven Nanofibrous Membranes for Sensors and Biosensors
Authors: Scampicchio Matteo , Bulbarello Andrea , Arecchi Alessandra , Cosio M. Stella , Benedetti Simona , Mannino Saverio 
Published: February 2012

AbstractThis review will focus on the recent advances on nanofibrous membranes (NFM) prepared by electrospinning (ES) applied to modify electrochemical sensors and biosensors. Most relevant applications of NFM include their used as selective barrier toward diffusion, protective coatings against fouling, conductive substrates for sensing applications, catalytic and biocatalytic membranes. The main advantages and drawbacks of these applications are critically assessed.
Ethmoid sinus osteoma: Diagnosis and management
Authors: Pons Yoann , Blancal Jean–Philippe , Vérillaud Benjamin , Sauvaget Elisabeth , Ukkola–Pons Elsa , Kania Romain , Herman Philippe 
Published: February 2012

AbstractBackgroundEthmoid sinus osteomas are uncommon, benign, osteogenic tumors. The purpose of this retrospective study was to describe their usual clinical presentation and to discuss their surgical management.MethodsThe medical records of 25 patients treated for ethmoid osteoma between March 2001 and December 2010 were retrospectively reviewed.ResultsThe average tumor size was 18.5 ± 14 mm. Only 3 patients were asymptomatic, 14 had a history of frontal sinusitis (complicated with orbital cellulitis in 4 cases), and 4 patients presented with diplopia. An endoscopic approach was performed in 19 cases, a coronal approach in 4 cases, and a combined approach (endoscopic + coronal) in 2 cases. No recurrence was reported.ConclusionEthmoid sinus osteoma can be asymptomatic and detected incidentally on CT scans, but often causes frontal sinusitis and orbital complications. The endoscopic approach offers the possibility of safe removal with cosmetic advantages compared to coronal approach. © 2012 Wiley Periodicals, Inc. Head Neck, 2013
Management of the neck and regional recurrence in squamous cell carcinoma of the maxillary alveolus and hard palate compared with other sites in the oral cavity
Authors: Brown James S. , Bekiroglu Fazilet , Shaw Richard J. , Woolgar Julia A. , Rogers Simon N. 
Published: February 2012

AbstractBackgroundThe aim of this article was to assess the management of the neck and regional recurrence for squamous cell carcinoma of the maxillary alveolus and hard palate (n = 43) and compare that to the rest of the oral cancer sites (n = 465).MethodsThis is a retrospective report through database and case note review.ResultsThe incidence of nodal metastases (pathologic node–positive necks added to regional recurrence for clinical N0 and pathologic N0) was 37% (16/43) for maxillary alveolus and hard palate compared with 40% (187/465) for the oral cavity in general. Regional recurrence occurred in 26% (11/43) in the maxillary alveolus and hard palate compared with 7% (31/465) in the remaining oral cavity sites (p = .001).ConclusionsSquamous cell carcinoma arising in the maxillary alveolus and hard palate has a similar risk of regional metastasis as the rest of the oral cavity, and a lower propensity for selective neck dissection is resulting in higher regional recurrence and lower survival rates. © 2012 Wiley Periodicals, Inc. Head Neck, 2013
Effect of fruit load on maturity and carotenoid content of clementine (Citrus clementina Hort. ex Tan.) fruits
Authors: Poiroux‐Gonord Florine , Fanciullino Anne‐Laure , Bert Liliane , Urban Laurent 
Published: February 2012

AbstractBACKGROUND: Citrus fruits contain many secondary metabolites displaying valuable health properties. There is a lot of interest in enhancing citrus quality traits, especially carotenoid contents, by agronomic approaches. In this study the influence of carbohydrate availability on maturity and quality criteria was investigated in clementine fruits during ripening. Fruiting branches were girdled and defoliated after fruit set to obtain three levels of fruit load: high (five leaves per fruit), medium (15) and low (30).RESULTS: Considering the soluble solid content/titratable acidity (SSC/TA) ratio, it was found that fruits of the high and medium fruit load treatments reached maturity 1.5 months later than fruits of the control. At the time of maturity the SSC/TA ratio of fruits of all treatments was about 13.6. At harvest, fruits were 23% smaller and total sugar concentration of the endocarp was 12.6% lower in the high fruit load treatment than in the control. In contrast, the concentrations of organic acids and total carotenoids were 55.4 and 93.0% higher respectively. Total carotenoids were not positively correlated with either soluble sugars or total carbohydrates.CONCLUSION: Taken together, the results do not support the common view that carbohydrate availability directly determines carotenoid synthesis by influencing precursor availability. Copyright © 2012 Society of Chemical Industry
Nepeta japonica Maximowicz extract from natural products inhibits lipid accumulation
Authors: Roh Changhyun , Jung Uhee 
Published: February 2012

AbstractBACKGROUND: To develop novel and crude anti‐obesity drugs from natural products is a promising field to approach the solution to a global health problem such as obesity. The aim of this study was to screen crude anti‐obesity drugs from 400 natural products on lipase inhibition activity in vitro.RESULTS: Among the natural products examined, 31 extracts showed significantly inhibition activity against porcine pancreatic lipase (triacylglycerol lipase, EC 3.1.1.3) by using spectrophotometry with 2,4‐dinitrophenylbutyrate as a substrate. Furthermore, 31 natural products were investigated with regard to their lipid inhibition in 3T3‐L1 cells. Among these, one of most promising was Nepeta japonica Maximowicz extract, which showed inhibition of triglyceride accumulation in 3T3‐L1 adipocytes, suggesting anti‐obesity activity. Also, the amount of glycerol released from cells into the medium was increased by treatment of Nepeta japonica Maximowicz extract at a concentration of 100 µg mL−1.CONCLUSION: The present study suggests that a promising crude anti‐obesity drug screened from 400 natural products might be of therapeutic interest with respect to the treatment of obesity. Copyright © 2012 Society of Chemical Industry
Does preoperative therapy optimize outcomes in patients with resectable pancreatic cancer?
Authors: Papalezova Katia T. , Tyler Douglas S. , Blazer Dan G. , Clary Bryan M. , Czito Brian G. , Hurwitz Herbert I. , Uronis Hope E. , Pappas Theodore N. , Willett Christopher G. , White Rebekah R. 
Published: February 2012

AbstractThe objective of this study was to compare survival between all patients with radiographically resectable adenocarcinoma of the proximal pancreas who underwent preoperative chemoradiation therapy (PRE‐OP CRT) or surgical exploration first (SURGERY) with “intention to resect.” Pancreatic cancer patients who undergo resection after PREOP CRT live longer than patients who undergo resection without PREOP CRT, a difference that may be attributable to patient selection. We retrospectively identified 236 patients with pancreatic head adenocarcinoma seen between 1999 and 2007 with sufficient data to be confirmed medically and radiographically resectable. The outcomes of 144 patients who underwent PREOP CRT were compared to those of 92 patients who proceeded straight to SURGERY. The groups were similar in age and gender. Tumors were slightly larger in the PREOP CRT group (mean 2.5 cm vs. 2.1 cm, P < 0.01), and there were trends toward more venous abutment (54% vs. 39%, P = 0.06) and a higher Charlson comorbidity index (P = 0.1). In the PREOP CRT group, 76 patients (53%) underwent resection, 28 (19%) had metastatic and 17 (12%) locally unresectable disease after PREOP CRT, and 23 (16%) were not explored due to performance status or loss to follow‐up. In the SURGERY group, 68 patients (74%) underwent resection. Sixteen patients (17%) had metastatic and eight patients (9%) locally unresectable disease at exploration. In patients who underwent resection, the PREOP CRT group had smaller pathologic tumor size and lower incidence of positive lymph nodes than the SURGERY group but no difference in positive margins or need for vascular resection. Median overall survival (OS) in patients undergoing resection was 27 months in the PREOP CRT group and 17 months in the SURGERY group (P = 0.04). Median OS in all patients treated with PREOP CRT or surgically explored with intention to resect was 15 and 13 months, respectively, with superimposable survival curves. Despite a lower resection rate, the PREOP CRT group as a whole had a similar OS to the SURGERY group as a whole. For patients who underwent resection, those in the PREOP CRT had longer survival than those in the SURGERY group, suggesting that PREOP CRT allows better patient selection for resection. PREOP CRT should be considered an acceptable alternative for most patients with resectable pancreatic cancer. J. Surg. Oncol. 2012; 106:111–118. © 2012 Wiley Periodicals, Inc.
UCST Behavior of Cyclodextrin‐Containing Poly(Pseudo‐Betaines) Based on Supramolecular Structures
Authors: Gonsior Nina , Ritter Helmut 
Published: February 2012

AbstractA novel monofunctional β‐cyclodextrin monomer is synthesized via copper(I)‐catalyzed azide/alkyne click reaction. By free radical polymerization, cyclodextrin‐containing polyelectrolytes can be obtained as an intriguing polymeric host for smart supramolecular assembling systems. By inclusion complexation of adamantyl carboxylate as a model guest, pseudo‐betaine structures with reversible UCST behavior are obtained. Furthermore, the complex stability constants are determined by isothermal titration calorimetry at different temperatures.
Towards Washout Filter Concepts for Motion Simulators on the Base of a Stewart Platform
Authors: Springer Klemens , Gattringer Hubert , Bremer Hartmut 
Published: February 2012

AbstractIn this paper we present a pneumatically driven Stewart platform as a basis for motion simulators. Motion platforms, that simulate perceived situations in aeroplanes, cars or ships, have workspace constraints in every degree of freedom. Therefore it is necessary to adapt the accelerations and angular rates in order to stay within the physical restrictions.For realizing a flight or ride simulator on the basis of the Stewart platform, “ Washout Filters” are used to change the signals of the open source software FlightGearand to minimize the sensation error between simulator and aircraft. Different filter concepts are implemented and evaluated.The platform presented in this document is a parallel kinematic robot, driven by fluidic muscles. The pneumatically actuated muscles are only able to produce tensile forces. Therefore a spiral spring from a passenger car is used to apply the compressive forces and torques. (© 2011 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Estimation of the optimal distribution of the fibers in carbon/carbon composite
Authors: Stasiuk Galyna , Piat Romana , Sinchuk Yuriy 
Published: February 2012

AbstractCarbon/carbon (C/C) composites are widely represented in the industry and are utilized for extreme thermal and mechanical loading. Optimization of the fibers distribution allows by still high stiffness to provide reducing of the weight of the components that has crucial importance in aircraft and aerospace industry. A microstructure optimization problem for estimation of the microstructure with minimal compliance is formulated. The design variables of the posed problem are the local fibers distribution and porosity. The volume fractions of the fibers and pores in the whole microstructure are fixed. (© 2011 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)