bluuebunny/crossref_metadata_2025_split huggingface dataset:
The compatibility of acyclovir with polyacrylonitrile in the electrospun drug‐loaded nanofibers
Authors: Yu Deng‐Guang , Branford‐White Christopher , Li Lan , Wu Xiao‐Mei , Zhu Li‐Min 
Published: March 2010

AbstractDrug delivery systems (DDS) derived from drug‐loaded fibers have attracted increasing attention in recent years. In this study, drug‐loaded nanofibers with varying drug‐to‐polymer ratios were prepared using electrospinning with acyclovir (ACY) as the model drug and polyacrylonitrile (PAN) as the filament‐forming matrix polymer. The compatibility of ACY with PAN was investigated by FTIR, DSC, XRD, and morphological studies. The obtained results clearly demonstrated that ACY had good compatibility with PAN and was able to be evenly distributed in the polymer fiber matrix. ACY present in the drug‐loaded fibers with a drug content of 10 wt % was in an amorphous state. As the ACY contents in the fibers increased up to 20 wt % drug crystals began to form and ACY separated from the fiber matrix. FTIR results illustrated that the main interactions between PAN and ACY was hydrogen bonding and data from 1H‐NMR showed that ACY was able to retain its chemical integrity during the electrospinning. All the fibers with varying drug content provided sustained drug release profiles over a 12‐h period. The drug‐loaded fibers prepared in this study could provide new approaches for developing novel transdermal DDS or skin topical DDS. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Dynamically vulcanized blends of polypropylene and ethylene octene copolymer: Influence of various coagents on thermal and rheological characteristics
Authors: Babu R. Rajesh , Singha Nikhil K. , Naskar Kinsuk 
Published: March 2010

AbstractThe present study focuses on the influence of the three structurally different coagents, namely triallyl cyanurate (TAC), trimethylol propane triacrylate (TMPTA) and N,N′‐m‐phenylene dimaleimide (MPDM) on the thermal and rheological properties of thermoplastic vulcanizates (TPVs) based on the polypropylene (PP) and ethylene octene copolymer (EOC). Depending on the structure and reactivity, different coagents show different behaviors. All the TPV compositions were made by melt mixing method in a Haake Rheomix at 180°C. Rheological properties have also been evaluated at the same temperature. Viscoelastic properties of the TPVs were analyzed by a dynamic oscillatory rheometer in the melt state in a Rubber Process Analyzer (RPA 2000). Morphologically, TPVs consist of dense crosslinked rubber domains dispersed in a continuous thermoplastic matrix. The crosslinked rubber particles have a tendency to form agglomerates and build local clusters which undergo disintegration by shearing. A variety of rheological characteristics such as Payne effect, shear rate sensitivity, modulus recovery and dynamics of relaxation were studied by performing strain sweep, frequency sweep and stress relaxation tests. Among the various coagents taken for investigation, MPDM‐based TPVs show improved dynamic functions (complex modulus and complex viscosity) and lower rate of stress relaxation over TAC, TMPTA and the control sample without any coagent. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Study on phase change characteristics of PEG/PAM coupling blend
Authors: Zhou Xiao‐Ming 
Published: March 2010

AbstractA novel solid–solid phase change materials with polyethylene glycol (PEG) worked as phase change substance and polyacrylamide (PAM) as solid skeleton was synthesized by coupling blend. Their phase change behaviors and structure analysis was studied by differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR), they had reversible solid–solid phase change properties. The result indicates that the PEG/PAM PCMs has great transition enthalpy and suitable phase transition temperature in the phase transition process. It can be considered as promising PCMs. Otherwise, their crystallization behavior were analyzed by polarization optical microscopy (POM), the crystalline degrees of these phase change materials were affected due to the intermolecular interaction and chemical bond. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Development of unsaturated polyester matrix – carbon nanofibers nanocomposites with improved electrical properties
Authors: Monti M. , Terenzi A. , Natali M. , Gaztelumendi I. , Markaide N. , Kenny J. M. , Torre L. 
Published: March 2010

AbstractIn this work, the dispersion of carbon nanofibers (CNFs) in an unsaturated polyester (UP) resin was performed by mean of the calendering process. The calendering process allows to obtain good dispersion of the nanoparticles, and, with respect to the other techniques, is also possible to scale it up at the industrial level. Optimization of the calendering conditions for the processing was carried out as a first step of this study. Optimization, in this case, means to reach the best dispersion level, as rapidly as possible and with the lowest amount of styrene evaporation. The dispersion level reached was investigated by the technique of scanning electron microscopy. The investigation on electric conductivity of the nanocomposites at different CNF concentrations has revealed that the electrical percolation threshold exists at around 0.3 wt %, where electrical conductivity switches from 10−13 to 10−7 S/cm. The rheological characterization has been performed to verify if the improved electrical properties are obtained at the expense of loss of workability, that is a significant increase of viscosity. Eventually, a mechanical characterization was carried out. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Water absorption of two different denture base resins reinforced with dental fiber systems
Authors: Durkan Rukiye Kaplan , Özdemir Tonguç , Pamir Ahmet Duru , Usanmaz Ali 
Published: March 2010

AbstractThe absorption of water by denture base materials is important because it is directly related with dimensional stability of dental material. In this study, water absorption of denture base materials reinforced with different type of dental fiber systems was compared. The samples were prepared from heat‐polymerized and microwave polymerized denture base resins and reinforced with different dental fiber systems. Five different reinforcement materials were used in this study, namely, (1) no fiber (control group), (2) plasma‐treated crosslinked polyethylene fibers, (3) plasma‐treated woven polyethylene fibers (4) porous polymer preimpregnated continuous unidirectional glass fibers, and (5) woven glass fibers. The water absorption calculations were done for the periods of 7, 14, 21, and 30 days of water immersion and in total 100 specimens were tested. The statistical analysis via analysis of variance and Duncan multiple comparison tests have shown that the fiber reinforcement significantly influence the water absorption. Moreover, the results have shown that water absorption of denture base polymers is higher when the specimens are reinforced with the fiber systems. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Thermodynamic study of the sulphonation of polystyrene‐butadiene rubber with chlorosulphonic acid for proton exchange membrane fuel cell
Authors: Idibie C. A. , Abdulkareem A. S. , Pienaar H. C. vZ. , Iyuke S. E. , vanDyk L. 
Published: March 2010

AbstractThe thermodynamic study of the sulphonation of polystyrene‐butadiene rubber (PSBR) with chlorosulphonic acid for fuel cell application was carried out. This was done to understand the properties of the sulphonation process in terms of the change in enthalpy (ΔH), entropy (ΔS), and the Gibbs free energy (ΔG) relative to product stability. The ΔH0, ΔS0, and ΔG0 were found to be 40.708 kJ, 64.22 J K−1, and 22.916 kJ, respectively, indicating that the reaction is not thermodynamically favorable (though nonsponteneous) where products are less favored compared to reactants which thus required energy. However, at elevated temperature (>328 K), a phase change from liquid to solid was encountered which suggests that the optimum temperature to carry out the sulphonation of PSBR in chlorosulphonic acid should be within 328 K. Results obtained also revealed that the sulphonation time influenced the qualities such as, proton conductivity, degree of sulphonation, and methanol permeability of the sulphonated PSBR. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Hydrogel‐MWCNT nanocomposites: Synthesis, characterization, and heating with radiofrequency fields
Authors: Satarkar Nitin S. , Johnson Don , Marrs Brock , Andrews Rodney , Poh Churn , Gharaibeh Belal , Saito Kozo , Anderson Kimberly W. , Hilt J. Zach 
Published: March 2010

AbstractHydrogel nanocomposites are attractive biomaterials for numerous applications including tissue engineering, drug delivery, cancer treatment, sensors, and actuators. Here we present a nanocomposite of multiwalled carbon nanotubes (MWCNT) and temperature responsive N‐isopropylacrylamide hydrogels. The lower critical solution temperature (LCST) of the nanocomposites was tailored for physiological applications by the addition of varying amounts of acrylamide (AAm). The addition of nanotubes contributed to interesting properties, including tailorability of temperature responsive swelling and mechanical strength of the resultant nanocomposites. The mechanical properties of the nanocomposites were studied over a range of temperatures (25–55°C) to characterize the effect of nanotube addition. A radiofrequency (RF) field of 13.56 MHz was applied to the nanocomposite discs, and the resultant heating was characterized using infrared thermography. This is the first report on the use of RF to remotely heat MWCNT‐hydrogel nanocomposites. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Spirituality and mental health
Authors: Koenig Harold G. 
Published: March 2010

AbstractSpirituality is increasingly being examined as a factor in mental health. Recent studies have found that spirituality may serve as a psychological and social resource for coping with stress. After defining the term spirituality, this paper examines some of the research on the relationship between spirituality and mental health, focusing on depression, anxiety, and substance abuse. While spiritual beliefs often represent powerful sources of comfort, hope and meaning, at times they can entangled with mental and emotional disorders making it difficult to determine whether they are a resource or a liability. Copyright © 2010 John Wiley & Sons, Ltd.
Near‐Infrared Organic Compounds and Emerging Applications
Authors: Qian Gang , Wang Zhi Yuan 
Published: March 2010

AbstractThis Focus Review describes the emerging class of near‐infrared (NIR) organic compounds containing the conjugated polyene, polymethine, and donor–acceptor chromophores and exploration of their NIR‐absorbing, NIR‐fluorescence, and NIR‐photosensitizing properties for potential applications in heat absorbers, solar cells, and NIR light‐emitting diodes. Examples of NIR organic compounds are reviewed with emphasis on the molecular design, NIR absorption, and fluorescence and particular emerging applications. The donor–acceptor type of NIR chromophores are particularly introduced owing to some unique features, including the designer‐made energy gaps, facile synthesis, good processability, and controllable morphology and properties in the solid state. Future directions in research and development of NIR organic materials and applications are then offered from a personal perspective.
Optimal grade transition control for liquid‐propylene polymerization reactor
Authors: Al‐haj Ali Mohammad 
Published: March 2010

AbstractA nonlinear control system integrating an off‐line optimizer and a nonlinear model‐based controller is developed to perform optimal grade transition operations in a continuous pilot plant reactor. A simple black‐box model is developed and used to determine optimal trajectories of inputs and outputs for a series of three polypropylene grades. The simplified model is also used to develop a nonlinear controller. This controller is similar to generic model control; however, the integral action is omitted and an on‐line updating scheme is incorporated to update pre‐specified model parameters using delayed process measurements. The time optimal inputs, which are calculated by the off‐line optimizer, are introduced to the plant in a feedforward manner. At the same time, the deviations from the optimal output are corrected using the feedback nonlinear controller. The simulations on a complex mechanistic model of the process reveal that the nonlinear control scheme performs well for both set point tracking and disturbance rejection. This paper integrates well‐known methodologies, such as the generic‐model control algorithm, parameter update schemes, and off‐line optimization, together to develop an applicable and robust control technique for continuous polymerization reactors. Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Numbers on the edges: A simplified and scalable method for quantifying the Gene Regulation Function
Authors: Fernandez‐Lopez Raul , del Campo Irene , Ruiz Raúl , Lanza Val , Vielva Luis , de la Cruz Fernando 
Published: March 2010

AbstractThe gene regulation function (GRF) provides an operational description of a promoter behavior as a function of the concentration of one of its transcriptional regulators. Behind this apparently trivial definition lies a central concept in biological control: the GRF provides the input/output relationship of each edge in a transcriptional network, independently from the molecular interactions involved. Here we discuss how existing methods allow direct measurement of the GRF, and how several trade‐offs between scalability and accuracy have hindered its application to relatively large networks. We discuss the theoretical and technical requirements for obtaining the GRF. Based on these requirements, we introduce a simplified and easily scalable method that is able to capture the significant parameters of the GRF. The GRF is able to predict the behavior of a simple genetic circuit, illustrating how addressing the quantitative nature of gene regulation substantially increases our comprehension on the mechanisms of gene control.
Research on small genomes: implications for synthetic biology
Authors: Klasson Lisa , Andersson Siv G. E. 
Published: March 2010

AbstractSynthetic genomics is a new field of research in which small DNA pieces are assembled in a series of steps into whole genomes. The highly reduced genomes of host‐associated bacteria are now being used as models for de novo synthesis of small genomes in the laboratory. Bacteria with the smallest genomes identified in nature provide nutrients to their hosts, such as amino acids, co‐factors and vitamins. Comparative genomics of these bacteria enables predictions to be made about the gene sets required for core cellular functions and the associated metabolic network for the biosynthesis of host‐selected compounds. Synthetic biology may ultimately enable researchers to make customized cell‐specific organelles for the production and delivery of drugs to humans and domestic animals. Synthetic genomics may also become the method of choice for functional analyses of genes and genomes from bacteria that cannot be cultivated in the laboratory.
A powerful toolkit for synthetic biology: Over 3.8 billion years of evolution
Authors: Rothschild Lynn J. 
Published: March 2010

AbstractThe combination of evolutionary with engineering principles will enhance synthetic biology. Conversely, synthetic biology has the potential to enrich evolutionary biology by explaining why some adaptive space is empty, on Earth or elsewhere. Synthetic biology, the design and construction of artificial biological systems, substitutes bio‐engineering for evolution, which is seen as an obstacle. But because evolution has produced the complexity and diversity of life, it provides a proven toolkit of genetic materials and principles available to synthetic biology. Evolution operates on the population level, with the populations composed of unique individuals that are historical entities. The source of genetic novelty includes mutation, gene regulation, sex, symbiosis, and interspecies gene transfer. At a phenotypic level, variation derives from regulatory control, replication and diversification of components, compartmentalization, sexual selection and speciation, among others. Variation is limited by physical constraints such as diffusion, and chemical constraints such as reaction rates and membrane fluidity. While some of these tools of evolution are currently in use in synthetic biology, all ought to be examined for utility. A hybrid approach of synthetic biology coupled with fine‐tuning through evolution is suggested.
Ethanol production from cellulosic materials using cellulase‐expressing yeast
Authors: Yanase Shuhei , Yamada Ryosuke , Kaneko Shohei , Noda Hideo , Hasunuma Tomohisa , Tanaka Tsutomu , Ogino Chiaki , Fukuda Hideki , Kondo Akihiko 
Published: March 2010

AbstractWe demonstrate direct ethanol fermentation from amorphous cellulose using cellulase‐co‐expressing yeast. Endoglucanases (EG) and cellobiohydrolases (CBH) from Trichoderma reesei, and β‐glucosidases (BGL) from Aspergillus aculeatus were integrated into genomes of the yeast strain Saccharomyces cerevisiae MT8‐1. BGL was displayed on the yeast cell surface and both EG and CBH were secreted or displayed on the cell surface. All enzymes were successfully expressed on the cell surface or in culture supernatants in their active forms, and cellulose degradation was increased 3‐ to 5‐fold by co‐expressing EG and CBH. Direct ethanol fermentation from 10 g/L phosphoric acid swollen cellulose (PASC) was also carried out using EG‐, CBH‐, and BGL‐co‐expressing yeast. The ethanol yield was 2.1 g/L for EG‐, CBH‐, and BGL‐displaying yeast, which was higher than that of EG‐ and CBH‐secreting yeast (1.6 g/L ethanol). Our results show that cell surface display is more suitable for direct ethanol fermentation from cellulose.
Identification of ilaprazole metabolites in human urine by HPLC‐ESI‐MS/MS and HPLC‐NMR experiments
Authors: Zhou Gan , Shi Shuyun , Zhang Wei , Tan Zhirong , Chen Yao , Guo Dong , Zhou Honghao , Hu Haitang , Tan Jin 
Published: March 2010

AbstractIlaprazole is a new proton pump inhibitor designed for the treatment of gastric ulcers, and limited data is available on the metabolism of the drug. In this article, the structural elucidation of urinary metabolites of ilaprazole in human was described by HPLC‐ESI‐MS/MS and stopped‐flow HPLC‐NMR experiments. Urinary samples were precipitated by sodium carbonate solution, and then extracted by liquid–liquid extraction after adding ammonium acetate buffer solution. The enriched sample was separated using a C18reversed‐phase column with the mobile phase composed of acetonitrile and 0.05 mol/L ammonium acetate buffer solution in a gradient solution, and then directly coupled to ESI‐MS/MS detection in an on‐line mode or1H‐NMR (500 MHz) spectroscopic detection in a stopped‐flow mode. As a result, four sulfide metabolites, ilaprazole sulfide (M1), 12‐hydroxy‐ilaprazole sulfide (M2), 11,12‐dihydroxy‐ilaprazole sulfide (M3) and ilaprazole sulfide A (M4), were identified by comparing their MS/MS and NMR data with those of the parent drug and available standard compounds. The main biotransformation reactions of ilaprazole were reduction and the aromatic hydroxylation of the parent drug and its relative metabolites. The result testified that HPLC‐ESI‐MS/MS and HPLC‐NMR could be widely applied in detection and identification of novel metabolites. Copyright © 2010 John Wiley & Sons, Ltd.
High‐performance liquid chromatographic enantioseparation of (R,S)‐fluoxetine using Marfey's reagent and (S)‐N‐(4‐nitrophenoxycarbonyl) phenylalanine methoxyethyl ester as chiral derivatizing reagents along with direct thin‐layer chromatographic resolution and isolation of enantiomers using l‐tartaric acid as mobile phase additive
Authors: Bhushan Ravi , Agarwal Charu 
Published: March 2010

AbstractChiral assay of enantiomers of fluoxetine was achieved in pharmaceutical formulations using direct and indirect methods. l‐Tartaric acid was used as a mobile phase additive in thin‐layer chromatography; the enantiomers were separated and isolated and were used to determine the elution order in HPLC. (R,S)‐flouxetine was derivatized with (S)‐N‐(4‐nitrophenoxycarbonyl)phenylalanine methoxyethyl ester [(S)‐NIFE], Marfey's reagent and 1‐fluoro‐2,4‐dinitrophenyl‐l‐methionine amide (FDNP‐l‐Met‐NH2). The diastereomers were separated using RP‐HPLC. The effect of flow rate and TFA concentration on resolution was studied. The diastereomers obtained by derivatization with FDNP‐l‐Met‐NH2 were also separated by RP‐TLC. Copyright © 2010 John Wiley & Sons, Ltd.
Analysis of amino acid neurotransmitters in hypothalamus of rats during cerebral ischemia–reperfusion by microdialysis and capillary electrophoresis
Authors: Li Hua , Yan Zhi‐ying 
Published: March 2010

AbstractIn this work, focal cerebral ischemia and reperfusion were induced by the model of middle cerebral artery occlusion. The dialysate of extracellular fluid in the hypothalamus of rats were obtained by using brain microdialysis technique. An efficient and sensitive MEKC method for the simultaneous determination of multiple amino acid neurotransmitters in microdialysate was developed by capillary electrophoresis with laser‐induced fluorescence detection and 5‐(4, 6‐dichloro‐s‐triazin‐2‐ylamino) fluorescein derivatization. Different parameters that influenced derivatization reaction and CE separation were studied and optimized. This method was used to investigate the dynamic change of fourteen amino acid neurotransmitters in microdialysates during cerebral ischemia/reperfusion period. Our results reveal that MCAO and reperfusion elicited significant increases in the extracellular levels of Arg, Lys, Trp, Phe, Gln, GABA, Asn, Pro, Ser, Ala, Tau, Gly, Glu and Asp. The excitatory/inhibitory neurotransmitter balance was disturbed during ischemia/reperfusion. The dynamic changes and functional status of releasable neurotransmitters during ischemia/reperfusion were discussed. Copyright © 2010 John Wiley & Sons, Ltd.
A novel educational platform to teach CANopen field bus
Authors: López‐López Fernando , Gomis‐Bellmunt Oriol , Teixidó‐Casas Miquel , Rafecas‐Sabaté Josep , Muñoz‐Gazquez Jose Pedro 
Published: March 2010

AbstractThis article presents a practical communications course focused on the CANopen field bus. The learning platform is composed by four nodes with real industrial devices, common in automation applications. The course has been put into practice by the CITCEA‐UPC in collaboration with Schneider Electric Spain. The course is devised both for university students and industry professionals. The problem proposed to the students is the configuration of a CANopen bus and the automation of a machine movement sequence. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 19: 377–384, 2011
Interactive educational software of textile design
Authors: Hernández‐Abad Francisco , Rojas‐Sola José Ignacio , Hernández‐Abad Vicente , Ochoa‐Vives Manuel , Font‐Andreu Jordi , Hernández‐Díaz David , Villar‐Ribera Ricardo 
Published: March 2010

AbstractThis article presents a novel educational software package which develops an Interactive Didactic Application(IDA) created by the Polytechnic University of Catalonia(UPC), and which contains the essentials of textile design. It is an open application which uses a database in ASCII format. The principal elements of this database are lists of whole numbers structured according to indexed colors in standard RGB format. This generates a rational system of indexes of numerical lists, which allows us to transmit knowledge in the different areas, which use images in their processes, with application in textile design, engineering graphics, mathematical transformations or indexation logic, among others. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 20: 161–174, 2012