bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interfacial interaction of polyvinylidene fluoride/multiwalled carbon nanotubes nanocomposites: A rheological study
Authors: Wen Rui , Ke Kai , Wang Yu , Yang Wei , Xie Bang‐Hu , Yang Ming‐Bo 
Published: March 2011

AbstractPolyvinylidene fluoride (PVDF)/multiwalled carbon nanotubes (MWCNTs) nanocomposites were prepared by solution blending method, and the melt viscoelastic behavior of the composites was studied. The results showed that the dispersion of MWCNTs in the matrix and the surface characteristic of MWCNTs had a profound influence on the melt rheological behaviors of the nanocomposites. Generally, the dynamic storage modulus (G′) of the nanocomposites with well dispersed MWCNTs was greatly improved. However, PVDF/MWCNTs‐g‐OH nanocomposites exhibit more significant solid‐like behavior than PVDF/MWCNTs nanocomposites at an MWCNTs loading of 2 wt % or higher, even though the dispersion of MWCNTs‐g‐OH is poorer than that of virgin MWCNTs owing to the higher interfacial interactions from van der Waals force and hydrogen bonding. In this case, the influence of the interfacial interactions on the melt rheological properties was stronger than the dispersion state. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Highly electrically conductive and injection moldable polymeric composites
Authors: Wu Tongfei , Pan Yongzheng , Li Lin 
Published: March 2011

AbstractHighly electrically conductive polypropylene (PP) composites were prepared by melt mixing using tin–lead (Sn‐Pb) alloy as conducting fillers. Two Sn‐Pb alloys, Sn‐Pb (20/80) and Sn‐Pb (40/60), were used for comparison. The effects of Sn‐Pb loading and molding temperature on electrical conductivity and mechanical properties of composites were investigated. It was found that both factors had significant effect on electrical conductivity of the final Sn‐Pb/PP composite. It was interesting to observe that the molding temperature could control the formation of long‐range conducting paths. The mechanism has been explored through the nonequilibrium phase behavior of Sn‐Pb alloy. The influence of Sn‐Pb loading on mechanical properties of Sn‐Pb/PP composites was also investigated. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Demonstration of the use of windows of operation to visualize the effects of fouling on the performance of a chromatographic step
Authors: Boushaba Rihab , Baldascini Helen , Gerontas Spyridon , Titchener‐Hooker Nigel J. , Bracewell Daniel G. 
Published: March 2011

AbstractThe high resolution afforded by packed bed chromatography makes it an indispensable operation in the downstream processing of therapeutic molecules. Packed bed performance is however inherently susceptible to changes in feed stream characteristics and fouling processes. The impact of fouling is seldom considered during the early stages of bioprocess development which is concerned with the selection of purification conditions. Instead these are performed with rigorously clarified feeds. Under such conditions, chromatography is effectively treated as an isolated step, independent from its preceding unit operations. In this study, we demonstrate how windows of operation could be used to visualize the impact of changes in the preceding clarification step on the fouling response of a subsequent cation exchange capture step. Laboratory columns (2,5 and 12 cm height) were subjected to varying fouling challenges of Escherichia coli lysate containing different amounts of solids carried over from the previous step. Changes in trans‐column pressure drop and breakthrough of the target protein (Fab′) were monitored. The limits of operability of the resin were determined with respect to the process material's properties. This information was used to extract the parameters for the adsorption kinetics used in the general rate (GR) model to create windows of operation for manufacturing scale operation. © 2011 American Institute of Chemical Engineers Biotechnol. Prog., 2011
Third in‐stent restenosis in sirolimus eluting stents
Authors: Ozawa Makito , Okamura Atsunori , Date Motoo , Higuchi Yoshiharu , Nagai Hiroyuki , Shibuya Masahiko , Ryusuke Kimura , Inoue Koichi , Koyama Yasushi , Iwakura Katsuomi , Fujii Kenshi 
Published: March 2011

AbstractObjectives:We evaluated the predictive factors for recurrent restenosis lesions treated on two previous occasions with sirolimus‐eluting stents (SES).Background:Angiography data related to recurrent SES restenosis have not been reported.Methods:Binary restenosis was observed in 66 patients with 78 lesions from a total of 1,393 patients with 1,965 lesions who received follow‐up angiography after SES implantation. We enrolled 55 patients with 67 lesions who underwent revascularization using another SES with a second follow‐up coronary angiography. These restenotic lesions were divided into two groups based on the presence or absence of recurrent restenosis: no recurrent restenosis group (n = 56) and recurrent restenosis group (n = 11). The coronary angiography data during first and second SES implantation were compared between the groups.Results:Minimal lumen diameter (MLD) was smaller before first and second percutaneous coronary interventions (PCI) with SES implantation in the recurrent restenotic group compared with no recurrent restenosis group (first PCI, 0.28 ± 0.19 mm vs. 0.54 ± 0.42 mm, P = 0.040; second PCI, 0.44 ± 0.36 mm vs. 0.69 ± 0.39 mm, P = 0.036, respectively). Acute stent recoil after second SES implantation was significantly greater in the recurrent restenosis group compared with no recurrent restenosis group (0.08 ± 0.17 mm vs. 0.20 ± 0.22 mm, P = 0.049, respectively). Multivariate analysis showed preprocedural MLD at first PCI and acute stent recoil at second PCI as independent predictors of recurrent restenosis.Conclusions:Preprocedural smaller MLD at first PCI and acute stent recoil at second PCI are predictors of recurrent restenosis treated on two previous occasions with SES. © 2011 Wiley Periodicals, Inc
Long‐term clinical outcomes of successful versus unsuccessful revascularization with drug‐eluting stents for true chronic total occlusion
Authors: Lee Seung‐Whan , Lee Jong‐Young , Park Duk‐Woo , Kim Young‐Hak , Yun Sung‐Cheol , Kim Won‐Jang , Suh Jon , Cho Yoon Hang , Lee Nae‐Hee , Kang Soo‐Jin , Lee Cheol Whan , Park Seong‐Wook , Park Seung‐Jung 
Published: March 2011

AbstractObjectives: The aims of this study were to investigate the long‐term clinical outcomes of patients with successful versus unsuccessful revascularization with drug‐eluting stents (DES) for chronic total occlusion (CTO). Background: The benefits of successful revascularization of CTO remain unclear. Methods: Consecutive patients (n = 333) with “true” CTO, defined as Thrombolysis In Myocardial Infarction (TIMI) flow grade 0 on angiography and duration ≥3 months, were divided into two groups, those with successful (CTO success group, n = 251) and unsuccessful (CTO failure group, n = 82) revascularization with DES for CTO lesions. The primary endpoint was defined as major adverse cardiac events (MACE) the composite of death, Q‐wave myocardial infarction (MI), or target vessel revascularization (TVR). Results: The CTO success group was significantly younger, with a higher involvement of LAD, and lower incidences of renal failure, previous myocardial infarction, and previous coronary intervention than the CTO failure group. After a median follow up of 1,317 days (interquartile range, 1,059–1,590 days), there were no significant between‐group differences in rate of MACE, both after crude analysis (9.4% vs. 11.8%, log‐rank P = 0.16) and after adjustment (HR 1.17; 95% CI 0.47–2.88, P = 0.53). On multivariate analysis, major predictors of MACE were left ventricle ejection fraction (LVEF) <40% (HR 3.14; 95% CI 1.39–7.09, P = 0.005) and multiple CTO (HR 2.38; 95% CI 1.01–5.71, P = 0.049). Conclusions: Long‐term clinical outcomes were similar in the CTO success and failure groups. Multiple CTOs and LVEF <40% in CTO patients were independent predictors of MACE. © 2011 Wiley‐Liss, Inc.
Comparison of novel sensory panel performance evaluation techniques with e‐nose analysis integration
Authors: Sipos László , Kovács Zoltán , Szöllősi Dániel , Kókai Zoltán , Dalmadi István , Fekete András 
Published: March 2011

AbstractReliability and validity of sensory data is an important issue in scientific researches. If sensory analysis is performed in an analytical approach, the resulting data will show a similar structure to the chemical analyses. In the present paper the authors have used a complex approach to evaluate the performance of a sensory panel. The tested samples were black tea batches from different plantations of Sri Lanka. Profile analysis was applied to identify the odor profiles of the samples. Sensory profile data was submitted to two novel techniques of panel performance evaluation. GCAP (Gravity Center Area/Perimeter) is based on the profile polygons of the individual assessors. If the area/perimeter ratio of two panelists' profiles is similar and the gravity center is located near to each other, the panelists performed the tests consistently. CRRN (Compare Ranks with Random Numbers) is applicable not only to sensory data but also to other field of chemometrics. The essence of CRRN method is based on the evaluation of an ‘average’ vector, corresponding to the coordinate‐averages of the measured points, and on a produced random vector series of the same dimension as the measured points. Sensory and e‐nose data were evaluated with principal component analysis, cluster analysis and linear discriminant analysis. Partial least square regression and support vector machine regression were used to predict sensory data with electronic nose results. Prediction by support vector machine gave close correlation between the results of electronic nose measurement and odor attributes. Copyright © 2011 John Wiley & Sons, Ltd.
Improved gas holdup in novel bubble column
Authors: Dhanasekaran S. , Karunanithi T. 
Published: March 2011

AbstractThis investigation reports the experimental and theoretical results carried out to evaluate the gas holdup for air–water system in a novel hybrid rotating and reciprocating perforated plate bubble column under countercurrent condition. The response of this hybrid column is found to be similar to that of reciprocating plate column (RPC) showing mixer‐settler, transition, and emulsion regions. The effect of agitation level, superficial gas velocity, superficial liquid velocity, perforation diameter, and plate spacing on gas holdup is studied and found to be significant. The gas holdup is found to be least in the range of agitation level of 1.3–1.5 cm/s. For all the superficial gas and liquid velocities considered in this present investigation, the critical agitation level at minimum gas holdup remains nearly same. The gas holdup in this hybrid column is 1.2–1.7 times higher in mixer‐settler region and 2.1–2.7 times higher in emulsion region than that of RPC. Correlations have been developed and found to concur with the experimental values. It can be used with 95% accuracy. © 2011 Canadian Society for Chemical Engineering
Residence time distribution in spouted bed drying of maltodextrin solutions on a bed of inert particles
Authors: Osorio‐Revilla Guillermo , Gallardo‐Velázquez Tzayhri , Ramírez‐Torres Arturo , Rivera‐Espinoza Yadira 
Published: March 2011

AbstractResidence time distributions (RTD) for aqueous maltodextrin solutions were determined in two kinds of spouted bed dryers: (1) conventional spouted bed (CSB) 0.305 m diameter with a bed of polypropylene beads and (2) spout‐fluid bed 0.143 m diameter with draft tube submerged in a bed of FEP® pellets (S‐FBDT). RTD, mean residence time tm, and spread of the distribution σ2, were determined at different drying temperatures, spouting velocities, bed depths, spraying pressures, and feed concentrations. Average values of tm and σ2 were 6.5 min and 26.6 min2 for the CSB and 6.9 min and 36 min2 for the S‐FBDT, respectively, for all operating conditions except spraying pressure. RTD curves were well represented by the response of an ideal stirred tank with a superimposed bypass of 15% on average for the CSB and 7% on average for the S‐FBDT dryer for all operating conditions. Increase in spraying pressure produced a reduction of tm and an increase in the bypass fraction of the product in both dryers. © 2011 Canadian Society for Chemical Engineering
Stability of slot‐rectangular spouted beds: Effect of slot configuration
Authors: Chen Z. , Lim C. J. , Grace J. R. 
Published: March 2011

AbstractExperiments were carried out to determine the flow stability of slot‐rectangular spouted beds of 300 × 100 mm cross‐section with slots of different widths, lengths, and depths. The effects of slot expansion angle and diverging base were also investigated. Dependent variables included the minimum spouting velocity, bed pressure drop and standard deviation of pressure fluctuations. Based on the flow regimes and spout termination mechanisms, instability was found to be mainly due to the interaction of multiple spouts. Criteria were identified relating stable spouting to slot dimensions and particle size. Slots of limited cross‐sectional area can provide sustainable and symmetric spouting with little fluctuation, as long as the slot length‐to‐width ratio and depth are within certain limits, related to those for conventional spouted beds.
Numerical simulation on wave behaviour and flow dynamics of laminar‐wavy falling films: Effect of surface tension and viscosity
Authors: Bo Shoushi , Ma Xuehu , Lan Zhong , Chen Hongxia , Chen Jiabin 
Published: March 2011

AbstractNumerical simulation has been made on wave behaviour and flow dynamics of falling films of aqueous lithium bromide solution along a vertical wall in the present study. Volume of fluid model is used to track the free surfaces and continuum surface force model is used for dynamic boundary conditions considering the effect of surface tension. A small amplitude forcing perturbation is introduced at the inlet of the flow boundary. Effect of surface tension and viscosity on wave behaviour and flow dynamics has been investigated. The simulation results indicate that wave peak height decreases with increasing surface tension and the number of capillary waves in front of a large wave increases. With the decrease of viscosity wave shape changes from the sinusoidal shape to the solitary one. Furthermore, the flow dynamics underneath the typical waves are analysed, especially the pattern of backflow. © 2011 Canadian Society for Chemical Engineering
Stagnation point flow towards a stretching/shrinking sheet in a micropolar fluid with a convective surface boundary condition
Authors: Yacob Nor Azizah , Ishak Anuar 
Published: March 2011

AbstractThe problem of a steady laminar two‐dimensional stagnation point flow towards a stretching/shrinking sheet in a micropolar fluid with a convective surface boundary condition is studied. The governing partial differential equations are transformed into ordinary differential equations using a similarity transformation, before being solved numerically using the Runge–Kutta–Fehlberg method with shooting technique. The effects of the material parameter and the convective parameter on the fluid flow and heat transfer characteristics are disscussed. It is found that the skin friction coefficient and the heat transfer rate at the surface decrease with increasing values of the material parameter. Moreover, dual solutions are found to exist for the shrinking case, while for the stretching case, the solution is unique. © 2011 Canadian Society for Chemical Engineering
CFD applied to turbulent flows in concentric and eccentric annuli with inner shaft rotation
Authors: Neto J. L. Vieira , Martins A. L. , Neto A. Silveira , Ataíde C. H. , Barrozo M. A. S. 
Published: March 2011

AbstractTurbulent flows in concentric and eccentric annuli with and without rotating inner cylinder were investigated by numerical simulations. Similar flows occur in drilling operations of oil wells. Several turbulence models with Reynolds Average Navier–Stokes approach were used in the simulations and the respective models predictions were compared with experimental data from the literature. The simulated results of axial and tangential velocities show a good agreement with the experimental data. As compared with another turbulence models, the simulations with the standard Reynolds Stress model presented a slightly better prediction for most of the responses studied.
Characterization of neuropeptide Y2 receptor protein expression in the mouse brain. II. Coexistence with NPY, the Y1 receptor, and other neurotransmitter‐related molecules
Authors: Stanić Davor , Mulder Jan , Watanabe Masahiko , Hökfelt Tomas 
Published: March 2011

AbstractNeuropeptide Y (NPY) is widely expressed in the brain and its biological effects are mediated through a variety of receptors. We examined, using immunohistochemistry, expression of the Y2 receptor (R) protein in the adult mouse brain and its association with NPY and the Y1R, as well as a range of additional neurotransmitters and signaling‐related molecules, which previously has not been defined. Our main focus was on the hippocampal formation (HiFo), amygdaloid complex, and hypothalamus, considering the known functions of NPY and the wide expression of NPY, Y1R, and Y2R in these regions. Y2R‐like immunoreactivity (‐LI) was distributed in nerve fibers/terminal endings throughout the brain axis, without apparent colocalization with NPY or the Y1R. Occasional coexistence between NPY‐ and Y1R‐LI was found in the HiFo. Following colchicine treatment, Y2R‐LI accumulated in cell bodies that coexpressed γ‐aminobutyric acid (GABA) in a population of cells in the amygdaloid complex and lateral septal nucleus, but not in the HiFo. Instead, Y2R‐positive nerve terminals appeared to surround GABA‐immunoreactive (ir) cells in the HiFo and other neuronal populations, e.g., NPY‐ir cells in HiFo and tyrosine hydroxylase‐ir cells in the hypothalamus. In the HiFo, Y2R‐ir mossy fibers coexpressed GABA, glutamic acid decarboxylase 67 and calbindin, and Y2R‐LI was found in the same fibers that contained the presynaptic metabotropic glutamate receptor 2, but not together with any of the three vesicular glutamate transporters. Our findings provide further support that Y2R is mostly presynaptic, and that Y2Rs thus have a modulatory role in mediating presynaptic neurotransmitter release. J. Comp. Neurol. 519:1219–1257, 2011. © 2011 Wiley‐Liss, Inc.
Multi‐GPU algorithm for k‐nearest neighbor problem
Authors: Kato Kimikazu , Hosino Tikara 
Published: March 2011

SUMMARYThe recommendation system is a mechanism which automatically recommends items that are likely to be of interest to the user. In the recommendation system, customers' preferences are encoded into vectors, and finding the nearest vectors to each vector is an essential part. This vector‐searching part of the problem is called a k‐nearest neighbor problem. We give an effective algorithm to solve this problem on multiple graphics processor units (GPUs). Our algorithm consists of two parts: the N‐body problem and the partial sort. For an algorithm of the N‐body problem, we applied the idea of a known algorithm, although another trick is needed to overcome the problem of small‐sized shared memory. For the partial sort, we give a novel GPU algorithm which is effective for small k. In our partial sort algorithm, a heap is accessed in parallel by threads with a low cost of synchronization. We show through an experiment that when the size of the problem is large, an implementation of the algorithm on two GPUs runs more than 330 times faster than a single core implementation on a latest CPU. Copyright © 2011 John Wiley & Sons, Ltd.
Rapid inexpensive assay method for verapamil by spectrophotometric sequential injection analysis
Authors: Idris Abubakr M. , Ibrahim Atta E. E. , Abulkibash Abdalla M. , Saleh Tawfik A. , Ibrahim Kamal E. E. 
Published: March 2011

AbstractSequential injection analysis (SIA) technique with a miniaturized fibre optic spectrophotometry was exploited to optimize and validate a new method for the assay of verapamil in pharmaceutical formulations. The reduction of acidified permanganate by verapamil was spectrophotometrically detected at 546 nm. The 23 full‐factorial design was adopted for screening the effect of conditions controlling the proposed method, and accordingly for the purpose of optimization. The remarkable advantages of the method are high rapidity (sample frequency was 10.6 samples/h), saving in reagents and sample (total consumed volume was 190 µl) and better safety for the environment (total waste production volume was 2140 µl). Additionally, the method was selective in the presence of excipients usually found in tablet and injection formulations. The average of recovery in synthetic samples as well as dosage forms was 98.8–103.0%. The obtained results were realized by the British Pharmacopoeia method and comparable results were obtained. Copyright © 2011 John Wiley & Sons, Ltd.
Quantitation of branched‐chain amino acids in ascites by capillary electrophoresis with light‐emitting diode‐induced fluorescence detection
Authors: Chang Po‐Ling , Chiu Tai‐Chia , Wang Tsang‐En , Hu Kuang‐Chun , Tsai Yu‐Hsien , Hu Cho‐Chun , Bair Ming‐Jong , Chang Huan‐Tsung 
Published: March 2011

AbstractBranched‐chain amino acids (BCAAs) are one of the important biomarkers for monitoring liver disease such as hepatitis or hepatoma. In this communication, we present the determination of the concentrations of BCAA in ascites by CE light‐emitted diode‐induced fluorescence (LEDIF) using 1.5% m/v poly(ethylene oxide) (average Mv: ∼8 000 000 g/mol) that was prepared in 10 mM sodium tetraborate solution (pH 9.3). Naphthalene‐2,3‐dicarboxaldehyde was used to derivatize 15 amino acids (AAs) to form naphthalene‐2,3‐dicarboxaldehyde (NDA)‐AA derivatives prior to CE analysis. The separation of 15 NDA‐AA derivatives was accomplished within 15 min, with RSD values of <5.8% (within‐day) and 7.4% (between‐days) with respect to their migration times. The limits of detection for the tested BCAAs ranged from 10.6 to 10.9 nM. We determined the concentrations of three BCAAs – leucine, isoleucine and valine – in ascites by applying a standard addition method, with recovery percentages ranging from 93.9 to 111%. The results obtained from this CE‐LEDIF method is in good agreement with those by a gold standard method using an AA analyzer. We have found that the concentrations of the three BCAAs in ascites obtained from patients suffering from liver diseases were lower than those from healthy individuals. Our approach is highly efficient, sensitive, and cost‐effective, which holds great potential for the diagnosis of liver diseases.
Affinity capillary electrophoresis and density functional theory employed for the characterization of hexaarylbenzene‐based receptor complexation with alkali metal ions
Authors: Ehala Sille , Toman Petr , Rathore Rajendra , Makrlík Emanuel , Kašička Václav 
Published: March 2011

AbstractIn this study, affinity capillary electrophoresis (ACE) and quantum mechanical density functional theory (DFT) calculations were combined to investigate non‐covalent binding interactions between the hexaarylbenzene‐based receptor (R) and alkali metal ions, Rb+ and Cs+, in methanol. The apparent binding (stability) constants (Kb) of the complexes of receptor R with alkali metal ions in the methanolic medium were determined by ACE from the dependence of effective electrophoretic mobility of the receptor R on the concentration of Rb+ and Cs+ ions in the BGE using a non‐linear regression analysis. The receptor R formed relatively strong complexes both with rubidium (log Kb=4.04±0.21) and cesium ions (log Kb=3.72±0.22). The structural characteristics of the above alkali metal ion complexes with the receptor R were described by ab initio density functional theory calculations. These calculations have shown that the studied cations bind to the receptor R because they synergistically interact with the polar ethereal fence and with the central benzene ring via cation‐π interaction.