bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hydrophobically modified poly(vinyl alcohol) and bentonite nanocomposites thereof: Barrier, mechanical, and aesthetic properties
Authors: Johansson Caisa , Clegg Francis 
Published: December 2014

ABSTRACTComposite films were formed by incorporating three different bentonites into an ethylene modified, water‐soluble poly(vinyl alcohol), EPVOH. The interaction of EPVOH with both hydrophilic and hydrophobic bentonites was investigated. EPVOH provided lower water vapor and oxygen transmission rates compared to a conventional PVOH grade when exposed at high relative humidities (70–90% RH). EPVOH films which exhibited oxygen barrier properties comparable to that of a biaxially oriented PET packaging film at 80% RH were produced. High compatibility between EPVOH and hydrophilic bentonites provided an even distribution of clay platelets in the composites. A strong increase in Young's modulus with increased addition of any of the three bentonites was found. At low addition levels the hydrophobic bentonite proved to be effective in terms of maintaining high elongation at break, high transparency and high gloss. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41737.
Preparation, characterization, and flocculation performance ofP(acrylamide‐co‐diallyldimethylammonium chloride) by UV‐initiated template polymerization
Authors: Guan Qingqing , Zheng Huaili , Zhai Jun , Liu Bingzhi , Sun Yongjun , Wang Yili , Xu Zhinan , Zhao Chun 
Published: December 2014

ABSTRACTThis study prepared TPDA, a high‐intrinsic‐viscosity cationic polyacrylamide, through ultraviolet (UV)‐initiated template polymerization. Acrylamide (AM) and diallyldimethylammonium chloride (DMD) served as monomers, and poly sodium polyacrylate (PAAS) served as the template. The structure of TPDA was characterized by Fourier‐transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy, and thermogravimetric analysis. The synthetic conditions of TPDA were studied and optimized by single‐factor experiments. An optimized product was obtained at an intrinsic viscosity of 11.3 dL g−1and a conversion rate of 97.2% with a total monomer concentration of 20%, DMD concentration of 30%, initiator concentration of 0.045%, pH of 8, EDTA concentration of 0.3%, and UV irradiation of 90 min. Results showed that TPDA was the copolymer of AM and DMD with a micro‐block structure at the molecular chain. Given its high intrinsic viscosity and cationic block structure, TPDA performed better in kaolin flocculation than that prepared without template addition. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2015,132, 41747.
Plasticization effects of dihydroxyl soybean oil improve flexibilities of epoxy‐based films for coating applications
Authors: Sung Jonggeun , Li Yonghui , Sun Xiuzhi Susan 
Published: December 2014

ABSTRACTNovel bio‐based coating materials were developed through cationic ring‐opening photopolymerization of dihydroxyl soybean oil (DSO) with commercial epoxy monomers [i.e., epoxidized soybean oil (ESO) and 3,4‐epoxycyclohexylmethyl‐3,4‐epoxycyclohexanecarboxylate (ECHM). The ether cross‐linking and post‐polymerization of the polymeric network were observed using Fourier transform infrared spectroscopy. Thermal properties of the bio‐based coating materials and their copolymerization behaviors were examined using differential scanning calorimetry and a thermogravimetric analyzer. Cross‐link density and molecular weight between cross‐link were obtained from dynamic mechanical analysis. ECHM/DSO (1 : 1.43 weight ratio) films showed the highest elongation at break (49.2%) with a tensile strength of 13.7 MPa. After 2 months of storage, the elongation at break and tensile strength of films were 32% and 15.1 MPa, respectively. ESO/DSO films (w/w ratios of 1 : 0.1, 1 : 0.15, and 1 : 0.2) exhibited stable flexibility of 11–13% of elongation at break without significant reductions in tensile strength (2.5–4.4 MPa) during a 2‐month shelf life. Optical transparencies of the films were comparable to commercial glass and polymers, and water uptake properties (0.72% and 2.83%) were significantly low. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41773.
A surface‐renewal model for constant flux cross‐flow microfiltration
Authors: Jiang Shaopeng , Chatterjee Siddharth G. 
Published: December 2014

ABSTRACTA mathematical model using classical cake‐filtration theory and the surface‐renewal concept is formulated for describing constant flux, cross‐flow microfiltration (CFMF). The model provides explicit analytical expressions for the transmembrane pressure drop (TMP) and cake‐mass buildup on the membrane surface as a function of filtration time. The basic parameters of the model are the membrane resistance, specific cake resistance, and rate of surface renewal. The surface‐renewal model has two forms: the complete model, which accounts for cake compressibility; and a subsidiary model for incompressible cakes, which can be derived from the complete model. The subsidiary model is correlated against some of the experimental TMP data reported by Miller et al. (J Membrane Sci 2014, 452, 171) for constant flux CFMF of a soybean‐oil emulsion in a cross‐flow filtration cell having unmodified and surface‐modified, fouling‐resistant membranes, and has an average root‐mean‐square (RMS) error of 6.2%. The complete model is fitted to the experimental TMP data reported by Ho and Zydney (J Membrane Sci, 2002, 209, 363) for constant flux microfiltration of a bovine serum albumin solution in a stirred cell using polycarbonate track‐etched membranes and has an average RMS error of 11.5%. This model is also correlated against the TMP data of Kovalsky et al. (J Membrane Sci 2009, 344, 204) for constant flux yeast filtration in a stirred cell (average RMS error = 9.2%). © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41778.
Ternary polymer blends based on poly(lactic acid): Effect of stereo‐regularity and molecular weight
Authors: Ross Sukunya , Mahasaranon Sararat , Ross Gareth M. 
Published: December 2014

ABSTRACTThe effects of stereo‐regularity and molecular weight of poly(lactic acid) (PLA) on ternary polymer blends was analyzed using optical clarity as the primary screening method. This enabled the ready identification of phase boundaries of optically clear and apparently miscible regions. Solvent‐mediated blends of amorphous poly(dl‐lactide) (PDLLA) and semi‐crystalline poly(l‐lactide) (PLLA) with various molecular weights from high to low, along with polycaprolactone (PCL) and cellulose acetate butyrate (CAB) were used in this study. The nature and extent of crystallinity of the blends was examined by X‐ray diffraction, which, in conjunction with differential scanning calorimetry, scanning electron microscopy, and Fourier transform infrared spectroscopy, provided information about the competition between polymer crystallization (self‐aggregating behavior) and intermixing of the macromolecules. Thus, allowing the primary physical cause of transparency loss to be identified. The results of the ternary blends optical clarity showed the position of the phase boundaries in PLLA/PCL/CAB and PDLLA/PCL/CAB blends are significantly affected by the stereo‐regularity and molecular weight of PLA. The PDLLA (amorphous) blend shows comparable regions of phase separation with high molecular weight and semi‐crystalline PLLA blends even though the molecular weight is much lower. The blends of the shorter chain PLLA1 tend to show more crystalline regions. The optical transparency, miscibility, and crystallinity of the blends are not only affected by the stereo‐regularity and molecular weight of PLA but also the crystallizable PCL, especially at high loading. These findings give useful information to the film‐packaging sector where good optical clarity is a critical performance requirement. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41780.
The effect of controlled degradation on the molecular characteristics of heterophasic ethylene–propylene copolymers
Authors: Swart Morne , Van Reenen Albert J. 
Published: December 2014

ABSTRACTA commercial heterophasic ethylene–propylene copolymer (HEPC) produced by Sasol Polymers using a Ziegler‐Natta catalysed gas‐phase process was vis‐broken (controlled degradation) to various degrees by making use of an organic peroxide. The effects of the amount of vis‐breaking on the molecular characteristics and physical properties were subsequently studied by making use of preparative Temperature Rising Elution Fractionation (p‐TREF), Nuclear Magnetic Resonance (NMR), Differential Scanning Calorimetry (DSC), High Temperature Size Exclusion Chromatography (HT‐SEC), and deposition of the SEC fractions via the LC Transform Interface (SEC‐FTIR). It was found that by increasing the amount of organic peroxide, the molecular characteristics of the heterophasic copolymer are severely affected and hence influence the physical characteristics of the polymer dramatically. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41783.
Nanomechanical properties and thermal stability of recycled cellulose reinforced starch–gelatin polymer composite
Authors: Rodríguez‐Castellanos Wendy , Flores‐Ruiz Francisco Javier , Martínez‐Bustos Fernando , Chiñas‐Castillo Fernando , Espinoza‐Beltrán Francisco Javier 
Published: December 2014

ABSTRACTSamples of starch−gelatin polymer reinforced with 5% of recycled cellulose were prepared using an extrusion‐compression molding process. Nanoindentation and atomic force acoustic microscopy (AFAM) techniques were used to study the effect of reinforcement at nanoscale level. Nanoindentation tests show a 163% increase in hardness and 123% of elastic modulus enhancement after recycled cellulose inclusion. AFAM shows that distribution of recycled cellulose into the polymer matrix is rather homogeneous at nanoscale which improves load transfer. Thermogravimetric analysis indicates an increase in thermal stability of the cellulose reinforced polymer matrix samples. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41787.
Pathways between soil moisture and precipitation in southeastern South America
Authors: Ruscica Romina C. , Sörensson Anna A. , Menéndez Claudio G. 
Published: December 2014

AbstractSoutheastern South America (SESA) is found to be the main hot spot of soil moisture–evapotranspiration coupling of South America during a dry summer. However, only its eastern part is a soil moisture–precipitation hot spot. Pathways between soil moisture and precipitation are evaluated through studying the coupling of soil moisture with surface and boundary layer variables. The outcome suggests that both the moist static energy and its vertical gradient are important for the development of precipitation, as a result of the total surface heat fluxes that are affected by soil moisture only in the eastern part of SESA.
Trends in the occurrence of new conduction abnormalities after transcatheter aortic valve implantation
Authors: van der Boon Robert M.A. , Houthuizen Patrick , Urena Marina , Poels Thomas T. , van Mieghem Nicolas M. , Brueren Guus R.G. , Altintas Sibel , Nuis Rutger Jan , Serruys Patrick W. , van Garsse Leen A.F.M. , van Domburg Ron T. , Cabau Joseph Rodés , de Jaegere Peter P.T. , Prinzen Frits W. 
Published: December 2014

ObjectivesThe aim of the study was to investigate trends over time in the occurrence of left bundle branch block (LBBB) and permanent pacemaker implantation (PPI) after transcatheter aortic valve implantation (TAVI) with the Medtronic CoreValve System (MCS) and Edwards SAPIEN Valve (ESV). Background: TAVI‐induced conduction abnormalities (TAVI‐CAs) such as LBBB and the need for PPI are frequent postoperative complication. New techniques, procedural refinements, and increased awareness are focused on the reduction of these abnormalities.MethodsElectrocardiograms of 549 patients without preprocedural LBBB and/or pacemaker were assessed to determine the frequency and nature of TAVI‐CAs. To study the effect of experience, patients were subdivided per center into tertiles based on the number of procedures. Univariate and multivariate logistic regression was used to study predictors of TAVI‐induced LBBB (TAVI‐LBBB) and PPI.ResultsTAVI‐LBBB occurred in 185 patients (33.7%) and significantly decreased over time, from 42.6% to 27.3% (P = 0.006). This effect was only significant after implantation of the MCS (59.6% vs. 46.5% vs. 31.1%, P = 0.001, ESV: 22.6% vs. 13.1% vs. 24.8%, P = 0.11). Between tertiles there was no difference in the frequency of PPI after TAVI (n = 73, 13.1% vs. 14.8% vs. 12%, P = 0.74). Multivariate analysis revealed that, independent from valve type, depth of implantation was the only significant predictor of TAVI‐LBBB (OR [95% C.I.]: 1.16 [1.10–1.24], P < 0.001). In case of PPI pre‐existing RBBB (OR [95% C.I.]: 7.22 [3.28–15.88], P < 0.001) was the only significant predictor.ConclusionsOver time the frequency of LBBB after TAVI decreased significantly, especially in patients undergoing TAVI with the MCS. Experience and the subsequent reduction in depth of implantation seem responsible for this reduction. Contrary to TAVI‐LBBB, the incidence of PPI remained unchanged over time and was not affected by experience. Although experience has led to a decrease in new CAs after TAVI, elucidation of pathophysiologic mechanisms underlying these CAs and subsequent changes in patient stratification, valve design and the procedure are needed to further reduce this complication. © 2014 Wiley Periodicals, Inc.
Comparison of primary percutaneous coronary intervention in patients withST‐elevation myocardial infarction during and prior to availability of an in‐houseSTEMIsystem: Early experience and intermediate outcomes of theHARRTprogram for achieving routineD2Btimes <60 minutes
Authors: Nguyen Bryant , Fennessy Michelle , Leya Ferdinand , Nowak Wojciech , Ryan Michael , Freeberg Sheldon , Gill Jasrai , Dieter Robert S , Steen Lowell , Lewis Bruce , Cichon Mark , Probst Beatrice , Jarotkiewicz Michael , Wilber David , Lopez John J. 
Published: December 2014

BackgroundOver the last decade, significant advances in ST‐elevation myocardial infarction (STEMI) workflow have resulted in most hospitals reporting door‐to‐balloon (D2B) times within the 90 min standard. Few programs have been enacted to systematically attempt to achieve routine D2B within 60 min. We sought to determine whether 24‐hr in‐house catheterization laboratory coverage via an In‐House Interventional Team Program (IHIT) could achieve D2B times below 60 min for STEMI and to compare the results to the standard primary percutaneous coronary intervention (PCI) approach.MethodsAn IHIT program was established consisting of an attending interventional cardiologist, and a catheterization laboratory team present in‐hospital 24 hr/day. For all consecutive STEMI patients, we compared the standard primary PCI approach during the two years prior to the program (group A) to the initial 20 months of the IHIT program (group B), and repeated this analysis for only CMS‐reportable patients. The D2B process was analyzed by calculating workflow intervals. The primary endpoint was D2B process times, and secondary endpoints included in‐hospital and 6‐month cardiovascular outcomes and resource utilization.ResultsAn IHIT program for STEMI resulted in significant reductions across all treatment intervals with an overall 57% reduction in D2B time, and an absolute reduction in mean D2B time of 71 min. There were no differences pre‐ and post‐program implementation in regard to individual or composite components of in‐hospital cardiovascular outcomes; however at 6 months, there was a reduction in cardiovascular rehospitalization after program implementation (30 vs. 5%,P < 0.01). The IHIT program resulted in a significant reduction in length‐of‐stay (LOS) (90 ± 102 vs. 197 ± 303 hr,P = 0.02), and critical care time (54 ± 97 vs. 149 ± 299 hr,P = 0.02).ConclusionsAvailability of an in‐house 24‐hr STEMI team significantly decreased reperfusion time and led to improved clinical outcomes and a shorter LOS for PCI‐treated STEMI patients. © 2015 Wiley Periodicals, Inc.
Fontan fenestration closure with Amplatzer Duct Occluder II device
Authors: McCrossan B.A. , Walsh K.P. 
Published: December 2014

ObjectivesTo evaluate Fontan fenestration closure using the Amplatzer Duct Occluder II device (ADO2).BackgroundFontan fenestration closure is a well established catheter intervention. A range of occlusion devices developed for other interventions have been utilized. Most of these devices, and especially the most commonly used Amplatzer Septal Occluder, are relatively bulky. The ADO2 is a low profile, flexible, and inexpensive device which seems well suited to the Fontan fenestration.MethodsThis study details retrospective review of patients undergoing Fontan fenestration closure with an ADO2 device. Outcome measures included procedural success, pre‐ and post‐procedural differences in oxygen saturation and mean pulmonary artery pressure and complications.ResultsThirteen patients were eligible for inclusion during the 34 month study period. All procedures were technically successful. There was a significant increase in oxygen saturations (Mean = +12%, P < 0.01) after fenestration closure but no significant change in mean pulmonary artery pressure (Mean = +0.5 mm Hg, P = 0.08). There were no procedural complications.ConclusionFontan fenestration closure with the ADO2 device is a simple, short, and cost‐effective procedure. The ADO2 characteristics recommend it to occlusion of varying sizes and morphologies of Fontan fenestration. © 2014 Wiley Periodicals, Inc.
Bronchoscopic guidance of endovascular stenting limits airway compression
Authors: Ebrahim Mohammad , Hagood James , Moore John , El‐Said Howaida 
Published: December 2014

ObjectiveBronchial compression as a result of pulmonary artery and aortic arch stenting may cause significant respiratory distress. We set out to limit airway narrowing by endovascular stenting, by using simultaneous flexible bronchoscopy and graduated balloon stent dilatation, or balloon angioplasty to determine maximum safe stent diameter.MethodsBetween August 2010 and August 2013, patients with suspected airway compression by adjacent vascular structures, underwent CT or a 3D rotational angiogram to evaluate the relationship between the airway and the blood vessels. If these studies showed close proximity of the stenosed vessel and the airway, simultaneous bronchoscopy and graduated stent re‐dilation or graduated balloon angioplasty were performed.ResultsFive simultaneous bronchoscopy and interventional catheterization procedures were performed in four patients. Median age/weight was 33 (range 9–49) months and14 (range 7.6–24) kg, respectively. Three had hypoplastic left heart syndrome, and one had coarctation of the aorta (CoA). All had confirmed or suspected left main stem bronchial compression. In three procedures, serial balloon dilatation of a previously placed stent in the CoA was performed and bronchoscopy was used to determine the safest largest diameter. In the other two procedures, balloon testing with simultaneous bronchoscopy was performed to determine the stent size that would limit compression of the adjacent airway. In all cases, simultaneous bronchoscopy allowed selection of an ideal caliber of the stent that optimized vessel diameter while minimizing compression of the adjacent airway.ConclusionIn cases at risk for airway compromise, flexible bronchoscopy is a useful tool to guide endovascular stenting. Maximum safe stent diameter can be determined without risking catastrophic airway compression. © 2014 Wiley Periodicals, Inc.
Chiral Recognition of Tyrosine Enantiomers Based on Decreased Resonance Scattering Signals With Silver Nanoparticles as Optical Sensor
Authors: Tan Xuanping , Li Qin , Shen Yizhong , Wu Huan , Zhao Yanmei , Yang Jidong 
Published: December 2014

AbstractA novel chiral sensing platform, employing silver nanoparticles capped with N‐acetyl‐L‐cysteine (NALC‐Ag NPs), was utilized for the discrimination of L‐tyrosine and D‐tyrosine. This nanosensor, which could be used as an optical sensing unit and chiral probe, was characterized by transmission electron microscopy (TEM) and resonance Rayleigh scattering (RRS) spectroscopy. After the proposed sensing platform interacted with L‐tyrosine and D‐tyrosine, a decreased resonance scattering signal was only obtained from L‐tyrosine. This phenomenon offered a useful assay for the selectivity and determination of L‐tyrosine with the RRS method. The linear range and detection limit of L‐tyrosine were 0.2838–20.0 µg⋅mL‐1 and 0.0860 µg⋅mL‐1, respectively. In addition, experimental factors such as acidity, interaction time, and the concentration of enantiomers were investigated with regard to the effect on enantioselective interaction. Chirality 27:194–198, 2015. © 2014 Wiley Periodicals, Inc.
Enantioselective Inhibition of Carprofen Towards UDP‐glucuronosyltransferase (UGT) 2B7
Authors: Fang Zhong‐Ze , Wang Haina , Cao Yun‐Feng , Sun Dong‐Xue , Wang Li‐Xuan , Hong Mo , Huang Ting , Chen Jian‐Xing , Zeng Jia 
Published: December 2014

AbstractUDP‐glucuronosyltransferases (UGTs)‐catalyzed glucuronidation conjugation reaction plays an important role in the elimination of many important clinical drugs and endogenous substances. The present study aims to investigate the enantioselective inhibition of carprofen towards UGT isoforms. In vitro a recombinant UGT isoforms‐catalyzed 4‐methylumbelliferone (4‐MU) glucuronidation incubation mixture was used to screen the inhibition potential of (R)‐carprofen and (S)‐carprofen towards multiple UGT isoforms. The results showed that (S)‐carprofen exhibited stronger inhibition potential than (R)‐carprofen towards UGT2B7. However, no significant difference was observed for the inhibition of (R)‐carprofen and (S)‐carprofen towards other UGT isoforms. Furthermore, the inhibition kinetic behavior was compared for the inhibition of (S)‐carprofen and (R)‐carprofen towards UGT2B7. A Lineweaver–Burk plot showed that both (S)‐carprofen and (R)‐carprofen exhibited competitive inhibition towards UGT2B7‐catalyzed 4‐MU glucuronidation. The inhibition kinetic parameter (Ki) was calculated to be 7.0 μM and 31.1 μM for (S)‐carprofen and (R)‐carprofen, respectively. Based on the standard for drug–drug interaction, the threshold for (S)‐carprofen and (R)‐carprofen to induce a drug–drug interaction is 0.7 μM and 3.1 μM, respectively. In conclusion, enantioselective inhibition of carprofen towards UDP‐glucuronosyltransferase (UGT) 2B7 was demonstrated in the present study. Using the in vitro inhibition kinetic parameter, the concentration threshold of (S)‐carprofen and (R)‐carprofen to possibly induce the drug–drug interaction was obtained. Therefore, clinical monitoring of the plasma concentration of (S)‐carprofen is more important than (R)‐carprofen to avoid a possible drug–drug interaction between carprofen and the drugs mainly undergoing UGT2B7‐catalyzed metabolism. Chirality 27:189–193, 2015. © 2014 Wiley Periodicals, Inc.