bluuebunny/crossref_metadata_2025_split huggingface dataset:
Radiation‐induced graft copolymerization of acrylic acid/acrylonitrile onto LDPE and PET films and its biodegradability
Authors: El‐Arnaouty M. B. , Abdel Ghaffar A. M. , El Shafey H. M. 
Published: September 2007

AbstractGraft copolymerization of acrylic acid/acrylonitrile (AAc/AN) comonomer onto low‐density poly(ethylene) (LDPE) and poly(ethylene terephthalate) (PET) films using direct radiation grafting technique has been investigated. The effect of different reaction conditions on the grafting yield was studied. The structure of the grafted films at different compositions was characterized by FTIR, TGA, SEM, and XRD. Biodegradation of grafted LDPE and PET was investigated by burial method in two types of Egyptian soils (agricultural and desert soils). The bacteria responsible for biodegradation were isolated and characterized, and the capacities for the growth on these polymers as substrates were compared. The isolates from agricultural soil were characterized as Pseudomonas, Alcaligenes, Bacillus, Proteus, and Enterobacter, whereas the isolates from desert soil were characterized as Alcaligenes, Bacillus, and Pseudomonas. The highest degradation rate was found to be achieved using agricultural soil. It is found that the isolated strains belonging to the genus Pseudomonas were mainly responsible for the degradation of both polymers. It has also been found that the increase of AAc ratio in the composition increases the hydrophilicity of the films and the degradation rate. PET polymer is generally found to be more resistant to the biodegradation than LDPE in the two types of soils tested. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Water‐repellent finishing of cotton fabrics by ultraviolet curing
Authors: Ferrero F. , Periolatto M. , Sangermano M. , Songia M. Bianchetto 
Published: September 2007

AbstractCotton fabrics were water‐repellent‐finished by radical ultraviolet curing of silicone and urethane acrylates with different formulations. The fabrics were impregnated with undiluted resins and with toluene solutions or water emulsions. Moreover, cationic ultraviolet‐curable systems were also investigated, such as an epoxy‐functional polysiloxane and mixtures of an epoxy resin with hydroxyl‐containing silicone additives. The gel content and polymerization yield were considered for the ultraviolet‐curing process evaluation. Water‐resistance properties were determined in terms of the contact angle, wettability, moisture adsorption, and water vapor permeability measurements, whereas the morphology and surface composition of treated fabrics were examined with scanning electron microscopy and energy‐dispersive X‐ray analysis. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Weak interaction, marginal miscibility, and ring‐band spherulites in blends of poly(vinylidene fluoride) with polyesters
Authors: Li Shu Hsien , Woo E. M. 
Published: September 2007

AbstractFourier transform infrared (FTIR) spectroscopy, optical microscopy (OM), and differential scanning calorimetry (DSC) techniques were used to probe phase behavior and interactions in blends of poly(vinylidene fluoride) (PVDF) and polyesters [poly(trimethylene adipate) (PTA) and poly(pentamethylene adipate) (PPA)] of relatively low crystallizability. DSC thermal analysis and OM characterization proved that PVDF was miscible with PTA and PPA with a low lower critical solution temperature. Small negative values of the interaction parameters (χ12 = −0.13 for a PVDF/PPA blend) were obtained with the melting‐point depression method. FTIR spectroscopy results revealed that interactions between CF2 of PVDF and the CO group of the polyester were weak, in agreement with the thermal analysis results. An increase in the coarseness and/or ring‐band spacing further provided supportive evidence that miscibility did exist between the polyester and PVDF constituents in the blends. Pattern changes in ring‐band spherulites of the miscible blends further substantiated the favorable, though weak, interactions between the PVDF and polyester constituents. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Tribological behavior of short‐fiber‐reinforced polyimide composites under dry‐sliding and water‐lubricated conditions
Authors: Chen Jiansheng , Jia Junhong , Zhou Huidi , Chen Jianmin , Yang Shiyong , Fan Lin 
Published: September 2007

AbstractPolyimide composites reinforced with short‐cut fibers such as carbon, glass, and quartz fibers were fabricated by the polymerization of monomer reactants process. The mechanical properties of the composites with different fiber contents were evaluated. The friction and wear properties of the polyimide and its composites were investigated under dry‐sliding and water‐lubricated conditions. The results indicated that the short‐carbon‐fiber‐reinforced polyimide composites had better tensile and flexural strengths and improved tribological properties in comparison with glass‐fiber‐ and quartz‐fiber‐reinforced polyimide composites. The incorporation of short carbon fibers into the polyimide contributed to decreases in the friction coefficient and wear rate under both dry and water‐lubricated conditions and especially under water lubrication because of the boundary lubrication effect of water. The polyimide and its composites were characterized by plastic deformation, microcracking, and spalling under both dry and water‐lubricated conditions, which were significantly abated under the water‐lubricated condition. The glass and quartz fibers were easily abraded and broken; the broken fibers transferred to the mating metal surface and increased the surface roughness of mating stainless steel, which led to the wear rate increasing for the glass‐fiber‐ and quartz‐fiber‐reinforced polyimide composites. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008
Semiflexible random thermotropic copolymers from 8‐(3‐hydroxy phenyl) octanoic acid and 3‐chloro‐4‐hydroxy benzoic acid/3,5‐dibromo‐4‐hydroxy benzoic acid
Authors: Mitra Sumi , Pillai C. K. S 
Published: September 2007

AbstractTwo series of semiflexible random thermotropic copolymers containing 8‐(3‐hydroxy phenyl) octanoic acid (HPOA) with either 3‐chloro‐4‐hydroxy benzoic acid or 3,5‐dibromo‐4‐hydroxy benzoic acid were prepared by melt polycondensation techniques. The copolyesters were characterized with Fourier transform infrared spectroscopy, dilute solution viscometry, hot‐stage polarized light microscopy, differential scanning calorimetry, thermogravimetric analysis, and wide‐angle X‐ray diffraction. Studies revealed that the amount of HPOA as a disruptor incorporated into the backbone of substituted 4‐hydroxy benzoic acids had a detrimental effect on the liquid‐crystalline behavior. Mesophase‐transition temperatures were observed between 210 and 250°C, and the optical textures were of typical nematic phases. The degree of crystallinity decreased with an increase in the HPOA content. The thermal stability of the copolymers was in the range of 310–370°C. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008
Ethynedithiol‐based polyeneoligosulfides as active cathode materials for lithium‐sulfur batteries
Authors: Trofimov B. A. , Myachina G. F. , Rodionova I. V. , Mal'kina A. G. , Dorofeev I. A. , Vakul'skaya T. I. , Sinegovskaya L. M. , Skotheim T. A. 
Published: September 2007

AbstractEthynedithiol‐based polyeneoligosulfides have been synthesized in 96% yield by the reaction of sodium acetylides (HCCNa, NaCCSNa) and elemental sulfur through the NaCsp bond in liquid ammonia with the following spontaneous polymerization of ethynedithiols (HSCCSH) formed by the hydrolysis. The polyeneoligosulfides synthesized are brown powders (up to 77% sulfur content, mp 128–184°C), partially soluble in organic solvents. They are high‐resistance semiconductors (10−13 to 10−14 S cm−1), possess paramagnetic (1017 to 1018 spin g−1) and redox properties. The oligosulfides obtained, being redox systems capable of reversible redox processes, provide high values of discharge capacity (345–720 mA h g−1) of rechargeable lithium‐sulfur batteries. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
When does a referent public problem affect financial and political support for public action?
Authors: Bonini Nicolao , Ritov Ilana , Graffeo Michele 
Published: September 2007

AbstractIn three studies we examined the willingness to support action to remedy a public problem. In Study 1 and Study 2, people were asked whether they would financially contribute to solution of a public problem. In Study 3, people were asked whether they would sign a petition to support a public action. The aim was to test whether the willingness to support solution of a public problem is affected by the type of problem that is used as the referent. We hypothesized that the willingness to support a public action is lower when evaluated in the context of a high‐ as opposed to a low‐importance referent problem (importance contrast effect). We also hypothesized that the importance contrast effect is tied to the perceived relatedness between the target and referent problems. The importance contrast effect should be found only when the two problems relate to different category domains. The findings bear out this prediction. Copyright © 2007 John Wiley & Sons, Ltd.
Retinoic acid‐mediated differentiation protects against nitrofen‐induced apoptosis
Authors: Aidlen Jeremy T. , Nazarey Pradeep P. , Kinane T. Bernard , Donahoe Patricia K. , Schnitzer Jay J. , Kling David E. 
Published: September 2007

AbstractBACKGROUND: Nitrofen is a diphenyl ether that induces a spectrum of birth defects subsequent to administration to pregnant rodents, in which the molecular etiology of these defects are poorly characterized. Because previous reports showed that nitrofen induced apoptosis in undifferentiated P19 teratocarcinoma cells, we hypothesized that undifferentiated fetal cells have greater susceptibility to nitrofen‐induced apoptosis than their differentiated derivatives. METHODS: To investigate this hypothesis, cell lines including P19 and F9 were differentiated with retinoic acid into neuronal and endodermal derivatives respectively. Apoptosis was characterized by caspase‐3 cleavage and Terminal transferase dUTP nick end labeling (TUNEL) assays. RESULTS: Both differentiated cell‐types had reduced nitrofen‐induced caspase‐3 cleavage and DNA fragmentation compared with the naive controls, strongly suggesting that differentiation of these cells protects against nitrofen‐induced apoptosis. In addition, resistance to apoptotic induction was proportional to the expression levels of the differentiation marker, p27 (kip1) while direct proportionality was not observed for the antiapoptotic protein Bcl‐2. CONCLUSIONS: These studies show that nitrofen may induce its associated birth defects via a mechanism involving apoptosis of undifferentiated fetal cells. Birth Defects Res (Part B), 2007. ©2007 Wiley‐Liss, Inc.
Protein secondary structure analyses from circular dichroism spectroscopy: Methods and reference databases
Authors: Whitmore Lee , Wallace B. A. 
Published: September 2007

AbstractCircular dichroism (CD) spectroscopy has been a valuable method for the analysis of protein secondary structures for many years. With the advent of synchrotron radiation circular dichroism (SRCD) and improvements in instrumentation for conventional CD, lower wavelength data are obtainable and the information content of the spectra increased. In addition, new computation and bioinformatics methods have been developed and new reference databases have been created, which greatly improve and facilitate the analyses of CD spectra. This article discusses recent developments in the analysis of protein secondary structures, including features of the DICHROWEB analysis webserver. © 2007 Wiley Periodicals, Inc. Biopolymers 89: 392–400, 2008.This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Recanalization of systemic venous baffles by radiofrequency perforation and stent implantation
Authors: Asgar Anita W. , Mirò Joaquim , Ibrahim Reda 
Published: September 2007

AbstractComplete transposition of the great arteries has been historically managed by the Mustard (atrial switch) operation. This procedure is associated with longterm complications such as baffle occlusion, which also precludes the insertion of a permanent transvenous pacemaker. Transcatheter techniques have allowed the successful angioplasty and stenting of stenotic baffles but complete occlusions continue to pose a therapeutic challenge. We report the use of a novel technique, a radiofrequency perforation wire for the management of complete occlusion of systemic venous baffles post‐Mustard operation. © 2007 Wiley‐Liss, Inc.
Management of cerebrovascular accidents during cardiac catheterization
Authors: De Marco Federico , Antonio Fernandez‐Diaz José , Lefèvre Thierry , Balcells Jordi , Araya Mario , Routledge Helen , Rosas Andrés , Louvard Yves , Dumas Pierre , Morice Marie‐Claude 
Published: September 2007

AbstractIschemic cerebrovascular events are a rare complication of cardiac catheterization. Consequently a unique standard of management for these events is yet to be defined. Immediate cerebral angiography followed by local thrombolysis is an effective strategy and we report six cases for which this approach was successfully employed. In contrast the use of immediate neuroimaging by means of MRI or CT scan in two cases delayed the implementation of appropriate therapy. © 2007 Wiley‐Liss, Inc.
Intermediate follow‐up following intravascular stenting for treatment of coarctation of the aorta
Authors: Forbes Thomas J. , Moore Phillip , Pedra Carlos A.C. , Zahn Evan M. , Nykanen David , Amin Zahid , Garekar Swati , Teitel David , Qureshi Shakeel A. , Cheatham John P. , Ebeid Makram R. , Hijazi Ziyad M. , Sandhu Satinder , Hagler Donald J. , Sievert Horst , Fagan Thomas E. , Ringwald Jeremy , Du Wei , Tang Liwen , Wax David F. , Rhodes John , Johnston Troy A. , Jones Thomas K. , Turner Daniel R. , Pass Robert , Torres Alejandro , Hellenbrand William E. 
Published: September 2007

AbstractBackground: We report a multiinstitutional study on intermediate‐term outcome of intravascular stenting for treatment of coarctation of the aorta using integrated arch imaging (IAI) techniques. Methods and Results: Medical records of 578 patients from 17 institutions were reviewed. A total of 588 procedures were performed between May 1989 and Aug 2005. About 27% (160/588) procedures were followed up by further IAI of their aorta (MRI/CT/repeat cardiac catheterization) after initial stent procedures. Abnormal imaging studies included: the presence of dissection or aneurysm formation, stent fracture, or the presence of reobstruction within the stent (instent restenosis or significant intimal build‐up within the stent). Forty‐one abnormal imaging studies were reported in the intermediate follow‐up at median 12 months (0.5–92 months). Smaller postintervention of the aorta (CoA) diameter and an increased persistent systolic pressure gradient were associated with encountering abnormal follow‐up imaging studies. Aortic wall abnormalities included dissections (n = 5) and aneurysm (n = 13). The risk of encountering aortic wall abnormalities increased with larger percent increase in CoA diameter poststent implant, increasing balloon/coarc ratio, and performing prestent angioplasty. Stent restenosis was observed in 5/6 parts encountering stent fracture and neointimal buildup (n = 16). Small CoA diameter poststent implant and increased poststent residual pressure gradient increased the likelihood of encountering instent restenosis at intermediate follow‐up. Conclusions: Abnormalities were observed at intermediate follow‐up following IS placement for treatment of native and recurrent coarctation of the aorta. Not exceeding a balloon:coarctation ratio of 3.5 and avoidance of prestent angioplasty decreased the likelihood of encountering an abnormal follow‐up imaging study in patients undergoing intravascular stent placement for the treatment of coarctation of the aorta. We recommend IAI for all patients undergoing IS placement for treatment of CoA. © 2007 Wiley‐Liss, Inc.
Successful complex bifurcation stenting of a native SFA after failed femoropopliteal bypass grafting
Authors: Kelley Michael , Mishkel Gregory 
Published: September 2007

AbstractEndovascular treatments are becoming more beneficial in the treatment of complex peripheral arterial disease. We report a novel case of using a y‐stenting technique at 2 bifurcation sites in the femoropopliteal region, to revascularize a long native SFA occlusion after failed femoropopliteal bypass grafting. © 2007 Wiley‐Liss, Inc.
Efficacy and long‐term patency of fenestrated amplatzer devices in children
Authors: Lammers Astrid E. , Derrick Graham , Haworth Sheila G , Bonhoeffer Philipp , Yates Robert 
Published: September 2007

AbstractIntroduction: Novel transcatheter techniques to control interatrial communications exist. Devices with restrictive fenestrations can be implanted to maintain patency of an atrial septostomy, or reduce an interatrial communication. Experience with these devices in children is limited. Patients and Methods: Fenestrated atrial septal devices were implanted into 10 children (5 male, age 1.5–15.5 years). Devices were modified by the manufacturer (MM, n = 6), or by a modification of an atrial septal occlusion device by the operator (OM, n = 4). Seven devices were implanted after atrial septal puncture and septostomy for severe symptomatic pulmonary hypertension (PHT) [4 heart failure, 3 syncope], according to World Health Organisation Guidelines. Two devices were implanted to reduce left to right shunting through large atrial septal defects with associated PHT. One device was implanted acutely to offload the left atrium during extracorporal circulatory support prior to heart transplantation. Warfarin (n = 5), aspirin (n = 4), or heparin (n = 1) were used for prevention of fenestration thrombosis. Results: Symptoms in all patients with PHT improved after implantation; syncope recurred with fenestration occlusion in one patient. Nine patients were followed up to a mean of 26 months. Five devices (all MM; warfarin n = 4, aspirin n = 1) remained patent on echocardiography. Fenestrations occluded in 4 children after median follow‐up of 10 months (MM n = 1, OM n = 3, warfarin n = 1, aspirin n = 3). Conclusions: Implantation of fenestrated atrial devices is feasible and effective; but the occlusion rate is high. Further research on fenestrated atrial septal devices with better long‐term patency, and effective antithrombotic drug treatment is necessary. © 2007 Wiley‐Liss, Inc.
The LightWire technology for catheter‐based interventions
Authors: Kornowski Ran , Miller Hylton I. , Shofti Rona , Lehrer Carmel , Matcovitch Avram , Sadka Elisabeth 
Published: September 2007

AbstractBackground: The LightWire is a newly developed opto‐acoustic coronary imaging guidewire that was designed to be used during angioplasty procedures and provide ‘online’ information on lumen and vessel wall dimensions. Methods: We designed in vitro models and performed animal trials to confirm proper device sensing capabilities and performance in the coronary arteries. This report focuses on maneuverability, compatibility with other catheterization devices, and vessel measurements. Results: Measurement ability was initially validated in vitro. Diameter measurements of coronary and peripheral arteries with and without stent based on ultrasound technology were then demonstrated in a pig model, whereas retaining easy navigation and maneuverability, as well as compatibility with other catheterization equipments. The LightWire device acquired proper and accurate multi‐location measurements of coronary and femoral artery diameters. Conclusion: Using a miniaturized opto‐acoustic technology can aid incoronary imaging, while maintaining standard guidewire performances. Thus, the LightWire device holds promise as a diagnostic and guidance tool during coronary and peripheral angioplasty procedures. © 2007 Wiley‐Liss, Inc.
Role of progenitor endothelial cells in cardiovascular disease and upcoming therapies
Authors: Kawamoto Atsuhiko , Asahara Takayuki 
Published: September 2007

AbstractThe field of cell‐based transplantation has expanded considerably and is poised to become an established cardiovascular therapy in the near future. In this review, we will focus on endothelial progenitor cells (EPCs), which are immature cells capable of differentiating into mature endothelial cells. EPCs share many surface marker antigens such as CD34, AC133, Flk‐1, etc. with hematopoietic stem cells (HSCs) and the major source of EPCs as well as HSCs is the bone marrow (BM). BM‐derived EPCs are mobilized into peripheral blood and recruited to the foci of pathophysiological neovascularization and reendothelialization, thereby contributing to vascular regeneration. Severe EPC dysfunction is an indicator of poor prognosis and severe endothelial dysfunction. Indeed, number of circulating EPCs and their migratory activity are reduced in patients with diabetes, coronary artery disease (CAD), or subjects with multiple coronary risk factors. Effective neovascularization induced by EPC transplantation for hindlimb, myocardial, and cerebral ischemia has been demonstrated in many preclinical studies, and early clinical trials of EPC transplantation in chronic and acute CAD indicate safety and feasibility of myocardial cell‐based therapies. For therapeutic reendothelialization in patients undergoing percutaneous coronary intervention, CD34 antibody‐coated stents have been used clinically to capture circulating EPCs at the injury sites and enhance reendothelialization and safety of stents. Further development in cell processing technology for efficient isolation, expansion, mobilization, recruitment, and transplantation of EPCs into target tissues are underway and expected to be tested in clinical trials in the near future. © 2007 Wiley‐Liss, Inc.
Highly Diastereo‐ and Enantioselective Direct Aldol Reactions of Aldehydes and Ketones Catalyzed by Siloxyproline in the Presence of Water
Authors: Aratake Seiji , Itoh Takahiko , Okano Tsubasa , Nagae Norio , Sumiya Tatsunobu , Shoji Mitsuru , Hayashi Yujiro 
Published: September 2007

AbstractProline‐based organocatalysts have been developed for a highly enantioselective, direct aldol reaction of aldehydes and ketones in the presence of water. While several surfactant–proline combined catalysts have proved effective, proline derivatives with a hydrophobic moiety such as trans‐siloxy‐L‐proline and cis‐siloxy‐D‐proline, both of which are easily prepared from the same commercially available 4‐hydroxy‐L‐proline, have been found to be the most effective organocatalysts examined in this study, affording the aldol product with excellent diastereo‐ and enantioselectivities, these two catalysts generating opposite enantiomers. Water affects the selectivity, and poor results are obtained under neat reaction conditions or in dry organic solvents. More than three equivalents of water are required for the best diastereo‐ and enantioselectivities, while three equivalents is the recommended amount from a synthetic point of view. The reaction proceeds in the organic phase, and also proceeds in the presence of a large amount of water. The large‐scale preparation of aldols with the minimal use of an organic solvent, including in the purification step, is described.