bluuebunny/crossref_metadata_2025_split huggingface dataset:
Heart valve stent for percutaneous implantation: Design optimization
Authors: Marchand Coralie , Heim Frédéric , Durand Bernard 
Published: October 2009

AbstractPercutaneous aortic valve implantation has become an alternative technique to surgical valve replacement in patients with high risk for surgery. This technique is at its beginning and stents used for valve prostheses remain standard vascular stents. These stents are, however, not designed to undergo heart valve stress. They do not match the aortic environment geometry, and induce exaggerated tissue traumatism. Reduced implant lifetime may therefore be expected. The purpose of this work is to evaluate in vitro the technical feasibility of noninvasive aortic valve replacement with a novel more specific stent. This stent is especially adapted to its implantation environment, with a design that matches the shape of the aortic root while respecting the valve function. To optimize the device's geometry, the influence of the design parameters on static and dynamic performances is studied in detail. For that purpose, the interaction between the stent and the aortic root is first studied theoretically, to highlight which parameters are relevant for further in vitro experiments. Static and dynamic regurgitation measurements are then performed to set the design parameters so as to optimize the behavior of the device implanted in a mock aortic root. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 2010
3‐Tesla magnetic resonance angiographic assessment of a tissue‐engineered small‐caliber vascular graft implanted in a rat
Authors: Yamanami Masashi , Yamamoto Akihide , Iida Hidehiro , Watanabe Taiji , Kanda Keiichi , Yaku Hitoshi , Nakayama Yasuhide 
Published: October 2009

AbstractIn the development of small‐caliber vascular grafts (diameter; less than 3 mm), animal implantation studies have been mostly performed by using rat abdominal aortas, and their certain patency must evaluate with sacrificing every observation periods, which is both labor‐intensive and time‐consuming when performing a large number of experiments. This study is the first to demonstrate the application of 3‐Tesla contrast‐free time‐of‐flight magnetic resonance angiography (TOF‐MRA) in the continuous assessment of the status of a tissue‐engineered vascular graft in rat. As a model graft, a single connective tubular tissue (diameter; 1.5 mm), prepared by embedding the silicone rod (diameter; 1.5 mm) into a subcutaneous pouch of a rat for 2 weeks an in vivo tissue‐engineering, was used. The graft was implanted in the abdominal aorta (diameter; 1.3 mm) of the rat by end‐to‐end anastomosis. Repeated TOF‐MRA imaging of the graft obtained over a 3‐month follow‐up period after implantation made it possible to evaluate the patency of the graft, both simply and noninvasively. It also permitted visualization of the connected abdominal aorta and renal and common iliac arteries having smaller caliber (diameter; less than 1 mm). In addition, the degree of the stenosis or aneurysm could also be detected. 3‐Tesla MRA allowed the simplified and noninvasive assessment of the status on the vascular graft, including the formation of a stenosis or aneurysm, in the same rat at different times, which will be contributing to enhance the development of tissue‐engineered vascular grafts even with small caliber. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 2010
Collagen II/hyaluronan/chondroitin‐6‐sulfate tri‐copolymer scaffold for nucleus pulposus tissue engineering
Authors: Huang Bo , Li Chang‐Qing , Zhou Yue , Luo Gang , Zhang Chuan‐Zhi 
Published: October 2009

AbstractThis study aims to investigate the bioactivity of collagen II/hyaluronan/chondroitin‐6‐sulfate tri‐copolymer as bionic scaffold for nucleus pulposus (NP) tissue engineering. Collagen II (C II) (pH 1–2) was mixed with hyaluronan (HyA) and lyophilized to prepare C II/HyA matrices. Chondroitin 6‐sulfate (6‐CS) was covalently attached to the C II/HyA matrices using 1‐ethyl‐3‐(3‐dimethyl aminopropyl) carbodiimide (EDC) and N‐hydroxysuccinimide (NHS). Then, cells were expanded from rabbit NP and seeded in the tri‐copolymer scaffold. Cell‐scaffold hybrids were maintained for up to 28 days in culture. Cell viability/proliferation, extracellular matrix (ECM)‐related gene expression, and the content of sulfated glycosaminoglycans (s‐GAG) were evaluated. Our results are as following: when cultured for 28 days, the cell‐scaffold hybrids maintained active cell viability/proliferation and exhibited a significantly increased s‐GAG content. In addition, rabbit NP cells cultured in the scaffold demonstrated a significantly higher level of C II and aggrecan gene expression and a significantly lower level of Collagen I (C I) gene expression when compared with that of monolayer cells. Histological studies and scanning electron microscopy (SEM) further indicated newly secreted ECM deposits in the scaffolds. In conclusion, the C II/HyA‐CS scaffold may be an alternative material for NP tissue engineering due to its satisfactory bioactivity, and it deserves further in vivo investigation. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010
Diffusion lung capacity for carbon monoxide (DLCO) is an independent prognostic factor for long‐term survival after curative lung resection for cancer
Authors: Liptay Michael J. , Basu Sanjib , Hoaglin Michael C. , Freedman Neil , Faber L. Penfield , Warren William H. , Hammoud Zane T. , Kim Anthony W. 
Published: October 2009

AbstractIntroductionWe examined the early and late prognostic significance of DLCO and forced expiratory volume in 1 sec (FEV1) in patients who underwent surgical resection of lung cancer.MethodsFrom 1997 to 2004, 462 patients underwent successful complete resection of their lung cancer and had full pulmonary function testing including DLCO performed. Mean follow‐up was over 5 years (64.8 months—range: 0–158 months).ResultsPostoperative 90‐day mortality was 2.6% (12/462). At last follow‐up, of the remaining 450 patients, 182 patients were alive, 130 had died of cancer, and 138 have died of other causes and did not have recurrent cancer. Mean DLCO values were 69.4%, 66.8%, and 53.9%, respectively. Mean FEV1 values were 81.3%, 78.1%, and 71.5%, respectively. Mean DLCOs and FEV1s between patients who died of cancer versus other causes were significantly different (P < 0.0001 and P = 0.0157). When cause‐specific survival was analyzed for both DLCO and FEV1 simultaneously, DLCO had a very significant effect on survival from other causes (HR 0.966, P < 0.0001) when adjusted for FEV1. However, when adjusted by DLCO, FEV1 had no significant effect. A DLCO <40% best predicted decreased survival from causes other than cancer within stage I lung cancers (stage IA HR 0.953, P < 0.0001; stage IB HR 0.968, P < 0.0001).ConclusionsDLCO was found to be a significant prognostic factor for long‐term survival after lung cancer surgery. This may serve as a surrogate for competing morbidities with declining values predicting a higher risk of late non‐cancer‐related death. J. Surg. Oncol. 2009;100:703–707. © 2009 Wiley‐Liss, Inc.
Borderline ovarian tumors and extended patient follow‐up: An individual institution's experience
Authors: Rettenmaier Mark A. , Lopez Katrina , Abaid Lisa N. , Brown John V. , Micha John P. , Goldstein Bram H. 
Published: October 2009

AbstractIntroductionBorderline tumors of the ovary (BOT) comprise nearly 20% of all ovarian malignancies and are associated with a favorable prognosis. However, since these lesions can present with malignant features and recur, a further evaluation of appropriate patient management and long‐term follow‐up is warranted.MethodsWe report a physician group's retrospective experience treating BOT patients at a single institution. Patient demographics, disease pathology, treatment type (surgery, chemotherapy), and patient surveillance (e.g., disease‐free survival (DFS), overall survival, follow‐up via CA‐125/radiology/physical exam) data were reviewed in all cases.ResultsIn the present study, 78 BOT patients treated from April 2001 until February 2009 were identified and confirmed via pathologic diagnosis. The majority (87%) underwent surgery, although nearly 13% of patients also received adjuvant chemotherapy. In the study population, 12% of the patients developed progressive disease, which was primarily detected via CA‐125 and physical exam/disease symptomatology. DFS for these patients was 38 months. Recurrent disease was significantly related to the administration of chemotherapy (P = 0.0024) and prolonged time since initial treatment (P < 0.001).DiscussionSince BOT can be aggressive and eventually recur, continued (i.e., long‐term) surveillance with CA‐125 evaluation and physical examination should be considered for optimal patient follow‐up. J. Surg. Oncol. 2010;101:18–21. © 2009 Wiley‐Liss, Inc.
E Pluribus Unum: fostering a new era of citizenship by teaching civic engagement and healthy civic discourse
Authors: Bole Barbara E. , Gordon Mark 
Published: October 2009

Abstract
In a time of profound national challenge and change, it is important to promote a new definition of active citizenship locally, nationally and globally. As the effects of economic, political and social globalization continue to underscore interdependence, the imperative of fostering democratic minds among a citizenry is evermore important. It is essential to conceive a common future that encourages the participation of all American citizens; inviting diversity as an asset and broadly reawakening the call to leverage the rich potentials of pluralism in search of common solutions. However, many schools are retreating from basic civics lessons and are not teaching students how to become active citizens. More importantly, public institutions overall do not appear to be advancing the fundamental awareness and skills required for sifting through political hucksterism, opinion masquerading as news and political spin. It is essential for our schools and public institutions to teach the responsibilities and joy of active citizenship. To meet the challenges of democratic cooperation and social cohesion, leaders and citizens alike should be taught and encouraged to openly question, to critique and even to criticize the status quo. The means for cultivating and institutionalizing such habits on a broad scale involves educational reformation and initiatives in civics and citizenship education to increase opportunities for meaningful public engagement. These are by no means the only answer, but they are a critical component for meeting the challenges of truly inclusive and active representative democracy where out of many, we are one.
Copyright © 2009 John Wiley & Sons, Ltd.
Fabrication of barium titanate nanoparticles‐epoxy resin composite films and their dielectric properties
Authors: Kobayashi Yoshio , Kurosawa Akira , Nagao Daisuke , Konno Mikio 
Published: October 2009

AbstractA method for fabricating epoxy resin films dispersing the surface‐modified barium titanate (BT) particles (BT‐epoxy resin composite films) are proposed. BT particles with a size of 7.8 nm and a crystal size of 8.6 nm were synthesized with a complex alkoxide method. To introduce epoxy groups on the BT particle surface, the BT particles were surface‐modified with 2‐(3,4‐epoxycyclohexyl)‐ethyltrimethoxysilane. A precursor solution, which was prepared by prereacting 2,2‐bis(4‐glycidyloxyphenyl)propane (BGPP) and phthalic anhydride in 4‐butyrolactone and adding the surface‐modified BT particles to the prereacting solution, was spin‐coated on glass substrates to fabricate the composite films. An increase in BT volume fraction in film increased dielectric constant of the composite film while keeping dissipation factor below 0.03. The dielectric constant attained 10.8 at a BT volume fraction of 30% in film that was around twice higher than pure epoxy resin film. POLYM. COMPOS., 31:1179–1183, 2010. © 2009 Society of Plastics Engineers
Influence of genetic variation inCYP3A4andABCB1on dose decrease or switching during simvastatin and atorvastatin therapy
Authors: Becker Matthijs L. , Visser Loes E. , van Schaik Ron H. N. , Hofman Albert , Uitterlinden André G. , Ch. Stricker Bruno H. 
Published: October 2009

AbstractPurposeSimvastatin and atorvastatin are metabolized by the CYP3A4 enzyme and transported by the ABCB1 transporter. We studied whether the polymorphismCYP3A4*1Band the polymorphisms C1236T, G2677A/T and C3435T in theABCB1gene were associated with a decrease of the prescribed dose or a switch to another cholesterol lowering drug during simvastatin and atorvastatin therapy. These events may indicate that statin plasma levels were too high and resulted in an adverse drug reaction or a too strong reduction in cholesterol level.MethodsWe identified 1239 incident simvastatin and atorvastatin users in the Rotterdam Study, a population‐based cohort study. Associations between the polymorphisms in theCYP3A4andABCB1gene and the time to a decrease in dose or a switch to another cholesterol lowering drug were studied using Cox proportional hazards.ResultsSimvastatin and atorvastatin users with theCYP3A4*1Bvariant G allele had a lower risk (HR 0.46; 95%CI 0.24–0.90) for these events than users with the wild‐type AA genotype. No significant associations were found for theABCB1polymorphisms. The association with theCYP3A4*1Bpolymorphism was found in women (HR 0.33; 95%CI 0.12–0.89) and was non‐significant in men (HR 0.69 95%CI 0.28–1.70). This association was stronger in patients with theABCB13435T variant alleleversusthe G allele.ConclusionIn simvastatin and atorvastatin users, theCYP3A4*1BG allele is associated with a lower risk of elevated statin plasma levels, particularly in women and in users with theABCB13435T variant allele. Copyright © 2009 John Wiley & Sons, Ltd.
Should response rules be used to decide continued subsidy of very expensive drugs? A checklist for decision makers
Authors: Bell Katy J. L. , Irwig Les , March Lyn M. , Hayen Andrew , Macaskill Petra , Craig Jonathan C. 
Published: October 2009

AbstractResponse rules are increasingly used by the Pharmaceuticals Benefits Scheme (PBS) in Australia and the National Institute of Clinical Excellence (NICE) in the U.K. to limit continued subsidy of very expensive drugs to patients who demonstrate an ‘adequate’ response. By targeting therapy to patients who appear to benefit most, policy makers aim to increase the cost‐effectiveness of therapy. However, the value of response rules in fulfilling this aim is unproven. We present a four‐item checklist that may be used to help decision makers identify when a response rule is appropriate. As an example, we apply our checklist to the response rules used for tumour necrosis factor (TNF) inhibitors in rheumatoid arthritis. On the basis of the checklist we find that the response rules in both countries are inadequate and may cause therapy to be inappropriately ceased in some and continued in others. Careful assessment is needed before decision makers adopt a response rule as a way of increasing the cost effectiveness of therapy. Copyright © 2009 John Wiley & Sons, Ltd.
Structural insight into the interaction of proteins containing NPF, DPF, and GPF motifs with the C‐terminal EH‐domain of EHD1
Authors: Kieken Fabien , Jović Marko , Tonelli Marco , Naslavsky Naava , Caplan Steve , Sorgen Paul L. 
Published: October 2009

AbstractEps15 homology (EH)‐domain containing proteins are regulators of endocytic membrane trafficking. EH‐domain binding to proteins containing the tripeptide NPF has been well characterized, but recent studies have shown that EH‐domains are also able to interact with ligands containing DPF or GPF motifs. We demonstrate that the three motifs interact in a similar way with the EH‐domain of EHD1, with the NPF motif having the highest affinity due to the presence of an intermolecular hydrogen bond. The weaker affinity for the DPF and GPF motifs suggests that if complex formation occurs in vivo, they may require high ligand concentrations, the presence of successive motifs and/or specific flanking residues.
Positronium interaction and its Bose‐Einstein condensation
Authors: Adhikari Sadhan K. 
Published: October 2009

AbstractWe present the actual state of affairs and future perspectives in the study of a quantum system of a collection of positronium (Ps) atoms. The interaction of a Ps atom with other atoms and molecules and specially with another Ps atom is described in some detail as Ps‐Ps interaction should play a crucial role in the dynamics of an assembly of Ps atoms. Using a simple model‐exchange potential, we could describe the available experimental results of Ps scattering reasonably well.The present scenario of the observation of Ps2 molecule, Ps Bose‐Einstein condensate (BEC) and the annihilation laser from a Ps BEC is presented. Possibilities of a Ps BEC formation via laser cooling of Ps atoms and via Ps formation in cavities are considered and difficulties with each procedure discussed (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Interfacial stabilization of binary polymer blends through radiation treatment: A free volume approach
Authors: Raj J. M. , Kumaraswamy G. N. , Ranganathaiah C. 
Published: October 2009

AbstractPartially miscible blends of PS/PMMA and PVC/SAN with different compositions have been prepared by solvent casting technique and characterized by Positron Annihilation Lifetime Technique. Phase modification in these systems has been brought out using e‐ beam and microwave irradiation. These changes have been studied through free volume monitoring. The changes in free volume parameters upon e‐beam and microwave irradiation on the two systems clearly shows improved interaction between the blend constituents as a result of cross‐linking through hydrogen bond formations. The free volume data indicates the overall changes in the blend with respect to free volume, but the extent of interfacial modification occurred for different weight compositions are not forthcoming upon irradiation. Therefore, the hydrodynamic interaction parameter α which accounts for excess friction thus dissipation of energy at the interface between the constituents of polymer blend system is evaluated for this purpose from the very same free volume data. The parameter α represents the strength of hydrodynamic interaction or it is a measure of the adhesion strength at the interface. Present data based on hydrodynamic interaction parameter indicated that both e‐beam and microwave irradiation can be used to stabilize the interfaces in binary polymer blends but the better interface modifier on the two blend systems studied. But which route that is e‐beam or microwave depends on the presence of non‐polar/polar groups respectively. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Spoliation of a rigid gas permeable contact lens by sodium chloride: A free volume microprobe study
Authors: Urs M. V. Deepa , Ranganathaiah C. 
Published: October 2009

AbstractThe interaction of one of the major inorganic ions present in tears, viz., sodium chloride (NaCl), with a rigid gas permeable contact lens, poly(Fluorosilicone acrylate) (FP92) has been investigated using Positron Annihilation Lifetime Spectroscopy (PLS) and refrac‐tive index measurement. We monitored the changes in its free volume size and number density in the presence of NaCl solute trans‐ported through diffusion. Based on PLS results, we propose that the adhesion of sodium chloride salt to the fluorine and methacrylate sites of FP92 results in zones of excess salt concentration. The changes in refractive index of the contact lens material due to the salt adhesion, correlates well with the changes in free volume of the material. Presence of sodium chloride perturbs the free volume of the lens material and hence its polarizability (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A unified linear Model Output Statistics scheme for both deterministic and ensemble forecasts
Authors: Vannitsem S. 
Published: October 2009

AbstractAn extension of the classical linear Model Output Statistics (MOS) technique is proposed allowing for the post‐processing of ensemble forecasts. In this new approach, the cost function on which the least square parameter estimation is based takes into account the presence of errors in both observations and model observables (referred to as Error‐in‐Variables MOS, EVMOS), unlike the classical linear MOS cost function whose implicit assumption is the absence of errors in the model observables. It allows for the maintenance of an appropriate variability for the corrected forecasts, even for long lead times and for providing a framework in which both deterministic and probabilistic forecasts can be corrected. The scheme is successfully tested for ensemble correction in the context of an idealized low‐order chaotic system, the Lorenz atmospheric model, in the presence of model errors, and compared with a classical technique, known as the non‐homogeneous Gaussian regression (NGR) method. The potential use of this approach is also briefly discussed. Copyright © 2009 Royal Meteorological Society
Phase‐locking of a rapidly developing extratropical cyclone by Greenland's orography
Authors: Kristjánsson Jón Egill , Thorsteinsson Sigurdur , Røsting Bjørn 
Published: October 2009

AbstractWe present HIRLAM simulations of a deep extratropical cyclone that developed off the southeast coast of Greenland on 2–3 March 2007. The purpose of the simulations is to understand the role of orographic forcing for the cyclone evolution, relating the results to previous model studies. The cyclone evolution was preceded by a powerful cold air outbreak over Greenland, starting on 27 February, manifested by a southward movement of an upper‐level potential vorticity (PV) anomaly from 80°N to 60°N. In addition to a CONTROL run, starting at 0000 UTC 2 March, which captures the main features of the cyclone evolution quite well, we have carried out simulations in which Greenland's orography was removed (NOGREEN), as well as simulations with different starting times. In the NOGREEN simulation starting at 0000 UTC 2 March, the cyclone deepens more rapidly than in CONTROL, due to a stronger cold advection on the rear side, leading to a more rapid baroclinic energy conversion. Furthermore, the cyclone position is shifted northward by 500 km, compared to the CONTROL run. A very different result is found in the NOGREEN simulations that were started 24–36 hours earlier, as the cyclone off Greenland's southeast coast is now displaced eastwards by hundreds of km, and more so as the run starts earlier. The results indicate a phase‐locking by Greenland of a transient PV anomaly, indicating a mechanism for understanding cyclogenesis in this area. Without Greenland's orography, the PV anomaly is unconstrained, and the curvature of its southward trajectory is larger. Copyright © 2009 Royal Meteorological Society
On time‐evolution of a balanced circular vortex
Authors: Kurgansky M. V. 
Published: October 2009

AbstractA simplified version of Eliassen's cyclostrophically and hydrostatically balanced circular vortex is considered, when the relative distribution of the tangential velocity is the same across the vortex at all altitudes (the similarity assumption). This vortex model mimics the high‐wind core of an intense tropical cyclone and might also be applicable to major tornadoes and to Martian giant dust devils. A self‐consistent problem is analytically solved to specify a slow time evolution of the primary and the secondary circulation in the vortex under the influence of the diabatic heating and the surface friction. The results show that a self‐similar balanced warm‐core vortex can either be stationary or decay (algebraically) in time, the latter for a vortex flow with incomplete similarity of the velocity field when the characteristics of the primary and the secondary circulation are scaled with height differently. Possible applications to the axisymmetric spin‐down dynamics of tropical cyclones are briefly discussed. Copyright © 2009 Royal Meteorological Society