bluuebunny/crossref_metadata_2025_split huggingface dataset:
ChemInform Abstract: Nanogels as Pharmaceutical Carriers: Finite Networks of Infinite Capabilities.
Authors: Kabanov Alexander V. , Vinogradov Serguei V. 
Published: September 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Synthesis and Molecular Structure of Silole Derivatives Bearing Functional Groups on Silicon: 1,1‐Organoboration of Dialkynylsilanes
Authors: Khan Ezzat , Bayer Stefan , Kempe Rhett , Wrackmeyer Bernd 
Published: September 2009

AbstractVarious dialkynylsilanes bearing Si–H or SiCl functions in addition to the alkynyl groups react with an excess of triethylborane after heating at 100–110 °C for several days via slow intermolecular 1,1‐ethylboration followed by fast intramolecular 1,1‐vinylboration to give Si‐functional substituted siloles. Similarly, the reactions with 9‐ethyl‐9‐borabicyclo[3.3.1]nonane afford polycyclic compounds containing the silole ring. Protodeborylaton with an excess of acetic acid leads to simultaneous substitution of BEt2 and Si–H functions to give 1‐acetoxysiloles. All new siloles were characterized by NMR spectroscopy in solution (1H, 11B, 13C, 29Si NMR), and for one example of a polycyclic silole derivative the molecular structure was determined by X‐ray analysis.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Continuous particle separation based on electrical properties using alternating current dielectrophoresis
Authors: Çetin Barbaros , Li Dongqing 
Published: September 2009

AbstractA design of a microchannel for continuous separation of particles based on alternating current dielectrophoretic is studied. The geometric design parameters are determined by analyzing the dielectrophoresis force field inside the microchannel corresponding to the most efficient separation. The trajectories of 5 and 10 μm spherical particles are derived analytically using Lagrangian tracking method to examine the feasibility and the effectiveness of the design. The effects of the mean flow velocity inside the channel and the applied voltage across the channel on the performance of the separation are also discussed.
Recursion approach for moving neutralization boundary formed on IPG strips Part I: With strong alkali rehydration buffer
Authors: Liang Heng , Chen Yang , Tian Li‐Jing , Zhang Lin 
Published: September 2009

AbstractMoving neutralization boundary (MNB) is an important foundation to understand and improve IEF. However, there are obstacles in theoretical predictions of MNB on IPG strips due to the unknown local concentrations of carrier ampholytes on commercial IPG strips and the time‐varying boundary velocities. We introduce a recursion approach to extend the current MNB theories into the space–time varying MNB system. The recursion approach emphasizes the localizability of physicochemical parameters in the discrete time intervals and local positions in Lagrangian coordinates, such as local concentrations of carrier ampholytes, local OH concentrations, local boundary velocities, local judgments, etc. The boundary‐position recursion equation in a complete time sequence was presented to quantitatively predict the MNB position–time curves by distinguishing three kinds of titration cases according to NaOH concentrations in rehydration buffers. The theoretical position–time curves and local relative judgments of boundaries were satisfactorily validated by corresponding images of boundary migrations achieved from the IPG‐MNB experiments with the some typical NaOH concentrations‐bromophenol blue‐rehydration buffers on pH 4–7 IPG strips. The results achieved herein have evident significances to the development of moving reaction boundary and IEF.
Enhancement of electrokinetically driven microfluidic T‐mixer using frequency modulated electric field and channel geometry effects
Authors: Yan Deguang , Yang Chun , Miao Jianmin , Lam Yeecheong , Huang Xiaoyang 
Published: September 2009

AbstractThis study reports improved electrokinetically driven microfluidic T‐mixers to enhance their mixing efficiency. Enhancement of electrokinetic microfluidic T‐mixers is achieved using (i) an active approach of utilizing a pulsating EOF, and (ii) a passive approach of using the channel geometry effect with patterned blocks. PDMS‐based electrokinetic T‐mixers of different designs were fabricated. Experimental measurements were carried out using Rhodamine B to examine the mixing performance and the micro‐particle image velocimetry technique to characterize the electrokinetic flow velocity field. Scaling analysis provides an effective frequency range of applied AC electric field. Results show that for a T‐mixer of 10 mm mixing length, utilizing frequency modulated electric field and channel geometry effects can increase the mixing efficiency from 50 to 90%. In addition, numerical simulations were performed to analyze the mixing process in the electrokinetic T‐mixers with various designs. The simulation results were compared with the experimental data, and reasonable agreement was found.
Evaluation of linear and nonlinear convection schemes on multidimensional non‐orthogonal grids with applications to KVLCC2 tanker
Authors: Ismail Farzad , Carrica Pablo M. , Xing Tao , Stern Frederick 
Published: September 2009

AbstractAlmost all evaluations of convection schemes reported in the literature are conducted using simple problems on uniform orthogonal grids; thus, having limited contribution when solving industrial computational fluid dynamics (CFD), where the grids are usually non‐orthogonal with distortions. Herein, several convection schemes are assessed in uniform and distorted non‐orthogonal grids with emphasis on industrial applications. Linear and nonlinear (TVD) convection schemes are assessed on analytical benchmarks in both uniform and distorted grids. To evaluate the performance of the schemes, four error metrics are used: dissipation, phase and L1 errors, and the schemes' effective order of accuracy. Qualitative and quantitative deterioration of these error metrics as a function of the grid distortion metrics are investigated, and rigorous verifications are performed. Recommendations for effective use of the convection schemes based on the range of grid aspect ratio (AR), expansion ratio (ER) and skewness (Q) are included. A ship hydrodynamics case is studied, involving a Reynolds averaged Navier–Stokes simulation of a bare‐hull KVLCC2 tanker using linear and nonlinear convection schemes coupled with isotropic and anisotropic Reynolds‐stress (ARS) turbulence models using CFDShip‐Iowa v4. Predictions of local velocities and turbulent quantities from the midships to the nominal wake plane are compared with experimental fluid dynamics (EFD), and rigorous verification and validation analyses for integral forces and moments are performed for 0° and 12° drift angles. Best predictions are observed when coupling a second‐order TVD scheme with the anisotropic turbulence model. Further improvements are observed in terms of prediction of the vortical structures for 30° drift when using TVD2S‐ARS coupled with DES. Copyright © 2009 John Wiley & Sons, Ltd.
SWAT model application and prediction uncertainty analysis in the Lake Tana Basin, Ethiopia
Authors: Setegn Shimelis G. , Srinivasan Ragahavan , Melesse Assefa M. , Dargahi Bijan 
Published: September 2009

AbstractLake Tana Basin is of significant importance to Ethiopia concerning water resources aspects and the ecological balance of the area. Many years of mismanagement, wetland losses due to urban encroachment and population growth, and droughts are causing its rapid deterioration. The main objective of this study was to assess the performance and applicability of the soil water assessment tool (SWAT) model for prediction of streamflow in the Lake Tana Basin, so that the influence of topography, land use, soil and climatic condition on the hydrology of Lake Tana Basin can be well examined. The physically based SWAT model was calibrated and validated for four tributaries of Lake Tana. Sequential uncertainty fitting (SUFI‐2), parameter solution (ParaSol) and generalized likelihood uncertainty estimation (GLUE) calibration and uncertainty analysis methods were compared and used for the set‐up of the SWAT model. The model evaluation statistics for streamflows prediction shows that there is a good agreement between the measured and simulated flows that was verified by coefficients of determination and Nash Sutcliffe efficiency greater than 0·5. The hydrological water balance analysis of the basin indicated that baseflow is an important component of the total discharge within the study area that contributes more than the surface runoff. More than 60% of losses in the watershed are through evapotranspiration. Copyright © 2009 John Wiley & Sons, Ltd.
Endocrine parameters of cystic fibrosis: Back to basics
Authors: Stalvey Michael S. , Flotte Terence R. 
Published: September 2009

AbstractDramatic changes in the life expectancy of cystic fibrosis (CF) patients are occurring, creating a cohort of aging individuals experiencing long‐term complications of this chronic disease. The two most common of these complications include CF‐related diabetes and CF bone disease. The clinical implications of each have become better understood, as have potential therapies. However, data obtained from the basic science studies of both diseases have not been widely recognized. In this review, we focus on the known and hypothesized pathogenesis of these two disorders. Additionally, the molecular underpinnings of CF will be explained along with the potential interactions with endocrine disease phenotypes. J. Cell. Biochem. 108: 353–361, 2009. © 2009 Wiley‐Liss, Inc.
Asymmetric flow field‐flow fractionation of liposomes: 2. Concentration detection and adsorptive loss phenomena
Authors: Hupfeld Stefan , Ausbacher Dominik , Brandl Martin 
Published: September 2009

AbstractThe applicability of different concentration detection methods for online quantification of liposomes upon asymmetric flow field‐flow fractionation was investigated. Filter‐extruded egg phosphatidylcholine liposomes of different size were used. Online quantification using a differential refractive index (dRI) detector was found feasible for relatively high sample loads in the magnitude of 100 μg lipid (under the chosen fractionation conditions). UV–Vis detection of the turbidity of liposomes was ruled out as online detection method because turbidity increases with particle size and the signal is not only concentration but also particle‐size dependent. Staining of liposomes by Rhodamine phosphatidylethanolamine or Sudan Red and subsequent online UV–Vis detection at the absorption maximum of the dye enabled quantification with much higher sensitivity than dRI detection. Furthermore analyte loss and carry‐over phenomena upon repeated injection of varying liposome sample loads were studied using regenerated cellulose (RC) membranes as accumulation wall. It could be shown that RC membranes are prone to adsorption in case of very small sample loads (0.5 μg). This effect may be overcome by pre‐saturation of the membrane with sample loads of at least 2 μg. For higher sample loads adsorptive losses play a minor role. Recovery from pre‐saturated membranes reached approximately 100% and carry‐over was found negligible.
Trace analysis of glyclazide in human plasma at microscale level by mass spectrometry
Authors: Feng Chia‐Hsien , Yang Chuan‐Ming , Lu Chi‐Yu 
Published: September 2009

AbstractGreen (reagents and organic solvents saving) analytical chemistry is a new strategy for pharmaceutical analysis. The principles of this idea include primary elimination or at least reduction of the amounts of organic reagents and solvents. In this study, we have provided two simple methods for the analysis of clinical drugs in human plasma. One is the capillary LC (Cap LC) connected to MS–MS, the other is the matrix‐assisted laser desorption ionization (MALDI) connected to TOF MS. Sulfonylurea drugs are usually used in diabetes mellitus patients. Diabetes is a syndrome of disordered metabolism resulting in abnormally high blood sugar levels (hyperglycemia). These microscale methods were successfully applied for the monitoring of drug levels in human plasma using gliclazide (a second‐generation sulfonylurea) as the test platform. The sensitivity of these methods is sufficient for detecting the gliclazide within a therapeutic range. All the analytical procedures (including human plasma, sample preparation, and flow rate of the analytical system) were at microscale level. These two methods would lower the consumption of organic solvents further safeguarding our environment.
Microwave extraction of essential oils from dried fruits of Illicium verum Hook. f. and Cuminum cyminum L. using ionic liquid as the microwave absorption medium
Authors: Zhai Yujuan , Sun Shuo , Wang Ziming , Cheng Jianhua , Sun Yantao , Wang Lu , Zhang Yupu , Zhang Hanqi , Yu Aimin 
Published: September 2009

AbstractIonic liquid was used as microwave absorption medium and applied to the extraction of essential oils from dried fruits of the Illicium verum Hook. f. and Cuminum cyminum L. by microwave‐assisted extraction. The extraction time is less than 15 min at the microwave power of 440 W. The constituents of essential oils obtained by the proposed method were compared with those obtained by hydrodistillation. There is no obvious difference in the constituents of essential oils obtained by the two methods.
Dietary fiber, low‐molecular‐weight food constituents and colo‐rectal inflammation in animal models – A review
Authors: Schrenk Dieter 
Published: September 2009

AbstractThis review provides an overview over studies in experimental animals aimed at elucidating the influence of dietary constituents on colo‐rectal inflammation. Human studies as well as in vitro investigations will not be covered. In experimental animals, a variety of chemical treatments and genetic modifications, lead to various types of gut inflammation. In a number of these models, there is good evidence for an anti‐inflammatory action of dietary tocopherols, certain polyphenols, and curcumin at relatively high oral doses. It has also been established, that oral application of fats and oils rich in n‐3 PUFAs and/or conjugated linoleic acid (CLA) can attenuate certain types of colitis in experimental animal models. While the effect of dietary calcium on experimental colitis is less clear, there are hints indicating that certain high‐fiber diets or diets rich in digestion‐resistant carbohydrates (“fiber”) can attenuate experimental colitis in animals, although contradictory results have been reported. In summary, the anti‐inflammatory potency of dietary constituents on colon inflammation in experimental animals seems to be rather limited. The reasons for this lack of activity seem to be manifold including pharmacokinetic limitations and intestinal degradation of the compounds, in particular insufficient local, i. e., intra‐ or sub‐mucosal levels of the effective compounds, and general limitations of animal models.
Prognostic significance of alterations in KRAS isoforms KRAS‐4A/4B and KRAS mutations in colorectal carcinoma
Authors: Abubaker Jehad , Bavi Prashant , Al‐Haqawi Wael , Sultana Mehar , Al‐Harbi Sayer , Al‐Sanea Nasser , Abduljabbar Alaa , Ashari Luai H , Alhomoud Samar , Al‐Dayel Fouad , Uddin Shahab , Al‐Kuraya Khawla S 
Published: September 2009

AbstractSomatic KRAS mutation is an early well‐known event in colorectal carcinogenesis but a complete understanding of RAS function and dysfunction in colorectal cancer is still to come. Our aim was to study the incidence of KRAS mutation; KRAS splice variants: KRAS4A and KRAS4B; and their relationships with various clinico‐pathological characteristics in colorectal cancer (CRC).In this study, 285 CRC cases were analysed for KRAS mutation by direct DNA sequencing followed by immunohistochemical analysis after validation with real‐time PCR assay, to study the protein expression of KRAS4A and ‐4B isoforms. KRAS gene mutations were seen in 80/285 CRCs (28.1%) and of the mutated cases, the majority of the mutations were seen in codon 12 (81.2%) as opposed to codon 13 (18.8%). CRCs with KRAS mutations were associated with a poor overall survival (p = 0.0009). Furthermore, KRAS mutations at codon 12 were associated with a poor overall survival of 64.4% at 5 years compared with a 5‐year overall survival of 75.8% and 78.2% with codon 13 mutation and absence of KRAS mutations, respectively (p = 0.0025). KRAS4A protein expression was predominantly seen in the cytoplasm, while KRAS4B protein was nuclear. KRAS4A overexpression was significantly associated with left colon, histology subtype of adenocarcinoma, p27kip1, and cleaved caspase3 expression. Interestingly, KRAS4A overexpression was associated with a better overall survival (p = 0.0053). On the other hand, KRAS4B overexpression (33.2%) was significantly associated with larger tumour size (p = 0.0234) and inversely correlated with p27kip1 protein (p = 0.0159). Both KRAS mutation and KRAS4A were independent prognostic markers in a multivariate analysis with age, gender, stage, differentiation, and MSI status. Our results highlight the differential role of KRAS isoforms in CRC, their utility as a prognostic biomarker, and underline the importance of KRAS alterations as a potential therapeutic target for CRC. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Online simulation‐based process control for injection molding
Authors: Johnston Stephen P. , Kazmer David O. , Gao Robert X. 
Published: September 2009

AbstractAn online numerical simulation is presented that is capable of predicting state variables such as flow rate, melt temperature, shear rate, and melt viscosity by using real time data from a nozzle pressure sensor. The simulation solves the non‐Newtonian nonisothermal polymer flow into multicavity tools while executing rapidly enough for real time process control. Numerical accuracy and stability were first validated offline by comparing the online simulation to results obtained from a commercial mold filling simulation. Simulation‐based process control was then demonstrated by transferring a molding machine from fill to pack‐based on the predicted flow front position. The simulation‐based controller dynamically determined the appropriate transfer position for each part and transferred the machine at the correct time, thereby eliminating flash. The simulation, however, did increase process variability slightly due to delay times associated with the controller‐machine interface. A full factorial design of experiments (DOE) was performed varying injection velocity, mold temperature, and melt temperature. Results show that while the simulation dynamically adjusted the process on a part‐by‐part basis, it did not fully account for the process changes. Accuracy could potentially be improved by incorporating data from additional process sensors, by developing adaptive viscosity models, and by accounting for the melt compressibility. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
Quantification of clay dispersion in nanocomposites of styrenic polymers
Authors: Carastan Danilo Justino , Vermogen Alexandre , Masenelli‐Varlot Karine , Demarquette Nicole Raymonde 
Published: September 2009

AbstractPolymer‐clay nanocomposites are materials with many interesting structures, properties, and potential applications. Microstructural evaluation of a nanocomposite is not an easy task, as clay may form hierarchical structures which may look different when observed at various magnifications under a microscope, and also as the concepts of “intercalation” and “exfoliation” are not self‐sufficient to describe its morphology. In this work polymer‐clay nanocomposites of polystyrene and two styrene‐containing block copolymers (styrene‐butadiene‐styrene and styrene‐ethylene/butylene‐styrene) were prepared using three different techniques. Clay dispersion was evaluated by a recently developed microscopy image analysis procedure, combining the analysis of optical and transmission electron micrographs, and the characterization was complemented by X‐ray diffraction and rheological measurements. The results showed better clay dispersion for both block copolymers nanocomposites, mainly due to their molecular architectures. Moreover, the techniques which showed the best results involved mixing the materials in a solvent medium. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
Rheology and dynamic mechanical analysis of bisphenol E cyanate ester/alumina nanocomposites
Authors: Sheng Xia , Akinc Mufit , Kessler Michael R. 
Published: September 2009

AbstractAlumina nanoparticles were functionalized with 3‐glycidyloxypropyl trimethoxysilane for compatibility with a low viscosity bisphenol E cyanate ester (BECy) resin. The functionalized alumina nanoparticles were characterized with Fourier transform infrared and thermogravimetric analysis. The alumina nanoparticles, which increase the viscosity of the BECy/alumina suspension, show a concurrent catalytic effect on the cure of the BECy resin, as indicated by reduced gelation times under isothermal cure conditions. Transmission electron microscopy micrographs reveal that most of the alumina nanoparticles are well dispersed in the BECy matrix, but a small fraction of particles formed agglomerates. The thermal‐mechanical properties of cured BECy composites reinforced with either bare alumina or functionalized alumina are evaluated by dynamic mechanical analysis. The storage modulus increases with both bare and functionalized alumina loading. Although the glass transition temperatures (Tg) of bare and functionalized alumina/BECy nanocomposites decrease with increasing filler content, the reduction in Tg is less severe when the alumina nanoparticles are first functionalized. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
Hydrogen bond interaction in poly(acrylonitrile‐co‐methylacrylate)/attapulgite nanocomposites
Authors: Yin Han , Chen Huifang , Chen Dajun 
Published: September 2009

AbstractIn this article, poly(acrylonitrile‐co‐methylacrylate)/attapulgite (AT) nanocomposites have been prepared by mechanical blending. The hydrogen bonding (H‐bonding) behavior between the copolymer and unmodified AT were investigated by Fourier Transform Infrared. The results indicated that the H‐bond index (HBI) decreased with increasing AT content. According to the dynamic mechanical analysis, the storage modulus and heat distortion temperature of the nanocomposites gradually increased with increasing AT content while the glass transition temperature reached the maximum when AT content was 1 wt%. X‐ray diffraction results demonstrated that the sample with the highest HBI value had the lowest crystallinity, suggesting the H‐bond interaction restricted the motion of polymer chains, thus decreased crystallinity of the nanocomposites. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers