bluuebunny/crossref_metadata_2025_split huggingface dataset:
Disposable Miniaturized Screen‐Printed pH and Reference Electrodes for Potentiometric Systems
Authors: Musa Arnaud Emmanuel , del Campo Francisco Javier , Abramova Natalia , Alonso‐Lomillo María Asunción , Domínguez‐Renedo Olga , Arcos‐Martínez María Julia , Brivio Monica , Snakenborg Detlef , Geschke Oliver , Kutter Jörg Peter 
Published: December 2010

AbstractThis work describes the development of a miniaturized potentiometric system comprising a miniaturized quasi‐reference electrode (QRE) coupled to a solid‐state ion‐selective electrode (ISE) for the monitoring of pH. We describe the optimization of materials and fabrication processes including screen‐printing (SP), electrode treatments (thermal and electrochemical) and the formulation and deposition of an ion‐selective membrane (ISM), to obtain a system compliant with biomedical specifications. We developed a potentiometric system composed of an Ag/AgCl QRE and a pH‐electrode (ISM deposited on a graphite electrode) that can be used continuously for a period of not less than 7 days in aqueous solutions. Curing the Ag/AgCl pastes during 20 minutes at 120 °C after printing allowed the QREs to display excellent potential stability, as demonstrated by an open‐circuit‐potential standard deviation of ±1.2 mV over a period of 7 days (n=3 samples). Promoting adhesion of the pH membrane over graphite electrodes improved the pH‐electrode performance. This was achieved through a combination of thermal treatment and electrochemical activation of the electrodes by cyclic voltammetry (CV). The final device integrated both the QRE and the pH‐electrode, and displayed an average pH sensitivity of −60.8±1.7 mV per pH unit, over a pH range of 7.00 to 7.63.
Theoretical models of separation selectivity for charged compounds in micellar electrokinetic chromatography
Authors: Puangpila Chanida , Petsom Amorn , Nhujak Thumnoon 
Published: December 2010

AbstractEquations and theoretical models for MEKC separation selectivity (αMEKC) were established to explain a change in separation and electrophoretic mobility order of fully charged analytes, in which αMEKC is related to the dimensionless values of mobility selectivity in CZE (αCZE) and retention selectivity (αk) in MEKC, and where αCZE and αk are defined as the ratio of electrophoretic mobility in CZE and the ratio of retention factor (k) in MEKC for two charged analytes, respectively. Using four alkylparabens as test analytes, excellent agreement was found between the observed αMEKC and the proposed αMEKC models of test analytes in MEKC over a wide range of SDS concentrations and values of k. For example, in comparison with CZE separation of charged analytes, MEKC separation can enhance separation selectivity up to the maximum value when the selectivity ratio (ρ) is greater than 1.0 (ρ=αk/αCZE), while lower separation selectivity is obtained with ρ<1.0 (αCZE>αk>1).
Bundled capillary electrophoresis using microstructured fibres
Authors: Rogers Benjamin , Gibson Graham T. T. , Oleschuk Richard D. 
Published: December 2010

AbstractJoule heating, arising from the electric current passing through the capillary, causes many undesired effects in CE that ultimately result in band broadening. The use of narrow‐bore capillaries helps to solve this problem as smaller cross‐sectional area results in decreased Joule heating and the rate of heat dissipation is increased by the larger surface‐to‐volume ratio. Issues arising from such small capillaries, such as poor detection sensitivity, low loading capacity and high flow‐induced backpressure (complicating capillary loading) can be avoided by using a bundle of small capillaries operating simultaneously that share buffer reservoirs. Microstructured fibres, originally designed as waveguides in the telecommunication industry, are essentially a bundle of parallel ∼5 μm id channels that extend the length of a fibre having otherwise similar dimensions to conventional CE capillaries. This work presents the use of microstructured fibres for CZE, taking advantage of their relatively high surface‐to‐volume ratio and the small individual size of each channel to effect highly efficient separations, particularly for dye‐labelled peptides.
5‐Aza‐2′‐deoxycytidine and interleukin‐1 cooperate to regulate matrix metalloproteinase‐3 gene expression
Authors: Couillard Julie , Estève Pierre‐Olivier , Pradhan Sriharsa , St‐Pierre Yves 
Published: December 2010

AbstractMembers of the matrix metalloproteinase (MMP) family of enzymes play a critical role in extracellular matrix remodeling in a number of normal and pathologic processes. Accordingly, activation of MMP gene expression is tightly regulated at the level of transcription by specific transcription factors, most notably following exposure to inflammatory cytokines. Recent studies with 5‐aza‐2′‐deoxycytidine (5‐aza‐dC), a specific DNA methylase inhibitor, also suggest that epigenetic processes contribute to the regulation of MMP expression. Although inflammation‐related aberrant patterns of DNA methylation have been described, a mechanistic link between inflammation and epigenetic alterations in the control of MMP expression remains unclear. Here, we provide evidence that increased MMP‐3 expression by 5‐aza‐dC is modulated by interleukin‐1 (IL‐1). More specifically, we found that stimulation with IL‐1, but not with IL‐6 or TNFα, significantly increased the hypomethylation status of the MMP‐3 promoter to a level similar to that found in dnmt1/dnmt3b‐deficient HCT116 (DKO) cells. Furthermore, we showed that increased MMP‐3 expression by 5‐aza‐dC was associated with increased expression and activity of specific transcription factors known to regulate MMP‐3 expression. In fact, treatment with 5‐aza‐dC was obligatory for some transcription factors to trigger an increase in MMP‐3 expression, such as Ap‐1. In contrast, CCAAT enhancer‐binding proteins and E‐twenty six were capable of inducing MMP‐3 alone. Overall, these findings provide a novel perspective of the collaborative role of 5‐aza‐dC and inflammatory cytokines with specific transcription factors that are normally involved in MMP‐3 expression.
Effects of Progesterone, Testosterone, and Estrogen on Sexual Reproduction of the RotiferBrachionus calyciflorus
Authors: Yang Jiaxin , Snell Terry W. 
Published: December 2010

AbstractIt is known that some vertebrate reproductive hormones have effects on rotifer reproduction, but little is known about their effects in combination. This motivated us to examine the effects of waterborne progesterone (P), testosterone (T), and estradiol (E) on reproduction of the rotiferBrachionus calyciflorus, comparing exposures to single hormones and mixtures with a total concentration of 1000 μg/L. Asexual population growth (r) was high in all treatments, ranging from 1.28 to 1.43 d–1(P‐E), and from 0.99 to 1.22 d–1(P‐T). These results indicate that E, P, or T alone, or in combinations of P‐E and P‐T totaling 1000 µg/L, and the 3‐way combination P‐E‐T at 1200 µg/L do not reduce the asexual reproduction ofB. calyciflorus. However, significant effects were detected on sexual reproduction with exposure to these hormone concentrations. Exposure to P‐T and P‐E at 1000 μg/L decreased resting egg production significantly. Analysis of mating indicated that fertilization was 5.3 times higher in the control than in treatments where females were exposed to 500 µg/L each P‐T. A similar result was observed when both females and males were exposed to 500 µg/L each of P‐T. When males alone were treated with 500 µg/L each of P‐T, there was no significant difference in male fertility compared to the control. These results suggest thatB. calyciflorususes oxidized sterols similar to P and T to regulate sexual reproduction and waterborne exposure of females to these compounds interferes with fertilization and resting egg production. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Inorganic coatings for cardiovascular stents: In vitro and in vivo studies
Authors: Mikhalovska Lyuba , Chorna Nataliya , Lazarenko Oleg , Haworth Peter , Sudre Arnaud , Mikhalovsky Sergey 
Published: December 2010

AbstractThe in‐vitro and in‐vivo biocompatibility of two oxides (TiO and ZrO) and diamond‐like carbon (D) coated stents has been assessed and compared with uncoated stainless steel (St) stents. In vitro studies demonstrated that both fibrinogen adsorption and platelet adhesion were significantly higher on D coating compared to those on oxide coatings and uncoated stainless steel. In addition TiO and ZrO coatings showed evidence of a minor inflammatory response and more complete endothelialization of the aorta than that seen around D coated and uncoated St stents. The resulting neointimal growth in the aorta with TiO, ZrO, and D coated and uncoated St stents, measured 8 weeks after stenting (the ratio of the neointima in the stented artery to the non‐stented artery) was 1.03 + 0.28, 0.85 + 0.36, 1.78 + 1.26, and 1.15 + 0.56, accordingly. From the data obtained it could be concluded that the increased neointima measured around D‐coated stents, may be due to both, the inferior haemocompatibility of the diamond‐like carbon coating and mechanical instability of D coating observed in an in vivo environment. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2011.
Anti‐DNA antibody modified coronary stent for plasmid gene delivery: results obtained from a porcine coronary stent model
Authors: Zhang Lin‐Hua , Luo Tong , Zhang Chao , Luo Peng , Jin Xu , Song Cun‐Xian , Gao Run‐Lin 
Published: December 2010

AbstractBackgroundPrevious work in our laboratory has demonstrated that the anti‐DNA antibody‐immobilized stent results in highly site‐specific gene delivery in a rabbit carotid model. As a result of the similarity in the anatomy and physiology of the pig and human cardiovascular systems, the porcine coronary stent model was used in the present study to evaluate the site‐specificity, efficiency and long‐term therapeutic effect of this gene delivery system in pig coronary arteries.MethodsA reporter plasmid pEGFP (pEGFP‐C1) was tethered on the antibody‐immobilized stents and assessed for site‐specificity and efficiency in a pig coronary stent model. Inducible nitric oxide synthase (NOS) cDNA (pcDNA3.1‐iNOS) was tethered on the stent as a therapeutic gene to evaluate the site‐specificity and long‐term therapeutic effect of this novel gene delivery system for the inhibition of restenosis after coronary stenting for 28 days.ResultsBoth the pEGFP‐C1 and pcDNA3.1‐iNOS tethered stents achieved site‐specific gene transfection without distal spreading in the porcine coronary model. The overall GFP transfection efficiency was 2.6 ± 0.9% of the total cells, whereas the neointimal transfection was more than 6%. Histology and morphology studies showed no significant artery stenosis and intimal proliferation for 28 days after coronary stenting using pcDNA3.1‐iNOS tethered stents.ConclusionsFor the first time, we report the successful use of anti‐DNA antibody‐immobilized stent as plasmid gene delivery system that possess high efficiency and site‐specificity in a porcine coronary stent model. The novel system showed long‐term therapeutic effects on the inhibition of restenosis when pcDNA3.1‐iNOS was tethered on the stent. Copyright © 2010 John Wiley & Sons, Ltd.
Tritium labelling of pharmaceuticals by metal‐catalysed exchange methods
Authors: Hesk D. , Lavey C. F. , McNamara P. 
Published: December 2010

AbstractMetal‐catalysed exchange with tritiated water and tritium gas has been extensively used to prepare a wide range of tritium‐labelled compounds in support of pharmaceutical research. Examples of the utility of both heterogeneous and homogeneous metal catalysts to label a very broad range of structures will be discussed in this review. Copyright © 2010 John Wiley & Sons, Ltd.
Novel isolation of phytochemical compositions by phase transition extraction with acetonitrile
Authors: Liu Guozhu , Yang Huawu , Zhang Mingshan , Li Shengjun , Chen Bo , Yao Shouzhuo 
Published: December 2010

AbstractBased on the phenomenon that hydrophilic acetonitrile can be separated from water by adding a hydrophobic solvent, a phase transition extraction (PTE) method for isolation of phytochemical compositions was developed. The isolation efficiency of the proposed method was assessed in complete grouping of the constituents in three important traditional Chinese medicine plants. Further study of the PTE for Scutellaria bacalensis Georgi found that the constituents in the organic phase are all flavonoid aglycones while the ones in the aqueous phase are all flavonoid glycosides, revealing the property of high structure selectivity for the proposed PTE process. The effect of using different modifiers on the isolation efficiency was investigated. The results obtained by using non‐oxygenated hydrophobic solvents are perfect while those by inorganic salts are acceptable, but those by oxygenated hydrophobic solvents are bad. Subsequent GC analysis revealed that the solvent composition difference between the two separated phases among PTE processes using different types of modifier is responsible for the different isolation results obtained. Finally, the proposed method was proved to be insensitive to both the acetonitrile concentration and the added amount of modifier.
Transparent and Conductive Graphene Oxide/Poly(ethylene glycol) diacrylate Coatings Obtained by Photopolymerization
Authors: Sangermano Marco , Marchi Sophie , Valentini Luca , Bon Silvia Bittolo , Fabbri Paola 
Published: December 2010

AbstractWater‐dispersed graphene oxide sheets were used to prepare graphene/poly(ethylene glycol) diacrylate resin composites by photopolymerization. It was found that graphene sheets undergo excellent morphological distribution within the resin system, giving rise to transparent composites with unaltered thermal properties with respect to the neat resin, that are electrically conductive at loading ratios as low as 0.02 wt.‐% of graphene oxide. The proposed strategy based on photopolymerization provides an easy, energy‐saving and environmental friendly technique that can find a wide application in coating technology, mainly for electromagnetic shielding and antistatic coatings. magnified image
Mass spectrometry‐based proteomics approaches applied in cataract research
Authors: Kyselova Z. 
Published: December 2010

AbstractCataract, the opacification of the eye lens, is the leading cause of blindness worldwide—it accounts for approximately 42% of all cases. The lens fibers have the highest protein content within the body, more than 35% of their wet weight. Given the eye lens pure composition of highly abundant structural proteins crystallins (up to 90%), it seems to be an ideal proteomic entity to study and might be also hypothesized to model the other protein conformational diseases. Crystallins are extremely long‐lived, and there is virtually no protein turnover. This provides great opportunities for post‐translational modifications (PTM) to occur and to predispose lens to the cataract formation. Despite recent progress in proteomics, the human lens proteome remains largely unknown. Mass spectrometry hold great promise to determine which crystallin modifications lead to a cataract. Quantitative analysis of PTMs at the peptide level with proteomics is a powerful bioanalytical tool for lens‐tissue samples, and provides more comprehensive results. New mass spectrometry‐based approaches that are being applied to lens research will be highlighted. Finally, the future directions of proteomics cataract research will be outlined. © 2010 Wiley Periodicals, Inc., Mass Spec Rev 30:1173–1184, 2011
Numerical modeling of hot tearing formation in metal casting and its validations
Authors: Zhu J. Z. , Guo J. , Samonds M. T. 
Published: December 2010

AbstractHot tearing is one of the most serious defects for a metal casting. The nucleation and propagation of the hot tearing can result in permanent defects in the casting, which may cause the final cast product to be unusable. It is believed that the imposed strains and stresses on the solid framework in the mushy zone by the solidification shrinkage and thermal contraction create the conditions for hot tearing. It has been very well documented that the composition of the alloy and the mechanical properties of the metals in the semi‐solid state play critical roles in the formation of hot tears. To predict the susceptibility of hot tearing in a casting, a hot tearing indictor is proposed which is based on Gurson's constitutive model and uses the thermophysical and thermomechanical properties obtained from a thermodynamic calculation in the final stage of solidification. The numerical implementation of the hot tearing indicator is described in detail and the numerical modeling of the hot tearing formation is validated by experiments. Copyright © 2010 John Wiley & Sons, Ltd.
Conforming local meshfree method
Authors: Tian Rong , To Albert C. , Liu Wing Kam 
Published: December 2010

AbstractThis work is motivated by the current numerical limitation in multiscale simulation of ductile fracture processes at scale down to the microstructure size and aims to overcome the difficulties in 3D complicated mesh generation and locally extremely large strain analysis (local mesh distortion). The proposed ‘conforming local meshfree approximation’ directly and exactly satisfies displacement compatibility on a non‐conforming assembly mesh. Local meshfree nodes, which can be freely placed and move on a finite element mesh, describe local large deformation. The improved accuracy on non‐conforming mesh, the exactness in geometry representation on a structured mesh, and the good tolerance to mesh distortion are demonstrated by numerical examples. Copyright © 2010 John Wiley & Sons, Ltd.
A new shell formulation using complete 3D constitutive laws
Authors: Sansalone M. , Sabourin F. , Brunet M. 
Published: December 2010

AbstractThis paper should not be only regarded as a presentation of new shell elements but rather as a methodology which can be applied to most classical shell elements and has two aims: Achieving the same results in bending cases while breaking from plane stress state hypothesis and adding a normal stress component for process simulations such as hydro‐forming, hemming, sheet metal forming with bottoming, flanging, incremental forming and so on. Owing to the non‐linear applications quoted before, only shell elements with one integration point on the mid‐plane are selected: Triangles that are naturally constant strain elements and reduced integration quadrilaterals. The method mainly consists of adding a central node at the center (of gravity for a triangle) with two degrees of freedom: Two translations normal to the mid‐surface for which one corresponds to the bottom surface (‘lower skin’ of the shell) and the other to the top surface (‘upper skin’ of the shell). Then a full 3D constitutive strain–stress behavior can be used. For triangles in bending state—either based on Kirchhoff's or on Mindlin's assumptions—, it is shown that the results are exactly the same as those given by the initial formulation of these elements using a plane stress hypothesis. For quadrilaterals, the results are slightly different but many numerical examples—including non‐linear computations—prove that those differences are not significant. Copyright © 2010 John Wiley & Sons, Ltd.
Preparation of cycloolefin copolymers of a bulky tricyclopentadiene
Authors: Park Hyeong Cheol , Kim Ahreum , Lee Bun Yeoul 
Published: December 2010

AbstractCopolymerizations of ethylene and tricyclopentadiene (TCPD) are realized without formation of a gel with a high activity (3–18 × 106 g/molZr·h) using a catalytic system of [Ph2C(Flu)(Cp)]ZrCl2/MMAO. The monomer reactivity ratios, rethylene and rTCPD, determined through the Fineman‐Ross plot, are 6.4 and 0.044, respectively, indicating that TCPD insertion is unfavorable, negligibly allowing the successive TCPD insertions. A significant higher glass transition temperature (Tg) is attained than those observed for other reported cycloolefin copolymers at the same cycloolefin content. A Tg as high as 214 °C is attainable at 41 mol % TCPD content. The remaining double bond can be hydrogenated to saturated hydrocarbon or converted to an epoxide group. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Characterizing diffusion dynamics of a membrane protein associated with nanolipoproteins using fluorescence correlation spectroscopy
Authors: Gao Tingjuan , Blanchette Craig D. , He Wei , Bourguet Feliza , Ly Sonny , Katzen Federico , Kudlicki Wieslaw A. , Henderson Paul T. , Laurence Ted A. , Huser Thomas , Coleman Matthew A. 
Published: December 2010

AbstractNanolipoprotein particles (NLPs) represent a unique nanometer‐sized scaffold for supporting membrane proteins (MP). Characterization of their dynamic shape and association with MP in solution remains a challenge. Here, we present a rapid method of analysis by fluorescence correlation spectroscopy (FCS) to characterize bacteriorhodopsin (bR), a membrane protein capable of forming a NLP complex. By selectively labeling individual components of NLPs during cell‐free synthesis, FCS enabled us to measure specific NLP diffusion times and infer size information for different NLP species. The resulting bR‐loaded NLPs were shown to be dynamically discoidal in solution with a mean diameter of 7.8 nm. The insertion rate of bR in the complex was ∼55% based on a fit model incorporating two separate diffusion properties to best approximate the FCS data. More importantly, based on these data, we infer that membrane protein associated NLPs are thermodynamically constrained as discs in solution, while empty NLPs appear to be less constrained and dynamically spherical.
Synergistic and antagonistic interactions of terpenes againstMeloidogyne incognitaand the nematicidal activity of essential oils from seven plants indigenous to Greece
Authors: Ntalli Nikoletta G , Ferrari Federico , Giannakou Ioannis , Menkissoglu‐Spiroudi Urania 
Published: December 2010

AbstractBACKGROUND:Biorational means for phytonematode control were studied within the context of an increasingly ecofriendly pest management global approach. The nematicidal activity and the chemical composition of essential oils (EOs) isolated from seven plants grown in Greece and ten selected compounds extracted from them against second‐stage juveniles (J2) ofMeloidogyne incognita(Kof. & White) Chitwood were evaluated using juvenile paralysis experiments. Additionally, synergistic and antagonistic interactions between nematicidal terpenes were studied using an effect addition model, with the comparison made at one concentration level.RESULTS:The 96 h EC50values ofFoeniculum vulgareMill.,Pimpinella anisumL.,Eucalyptus meliodoraA Cunn ex Schauer andPistacia terebinthusL. were 231, 269, 807 and 1116 µg mL−1, respectively, in an immersion bioassay. Benzaldehyde (9 µg mL−1) was the most toxic compound, followed by γ‐eudesmol (50 µg mL−1) and estragole (180 µg mL−1), based on 96 h EC50values. The most potent terpene pairs between which synergistic actions were found, in decreasing order, were:trans‐anethole/geraniol,trans‐anethole/eugenol, carvacrol/eugenol and geraniol/carvacrol.CONCLUSION:This is the first report on the activity ofF. vulgare, P. anisum, E. meliodoraandP. terebinthus, and additionally on synergistic/antagonistic nematicidal terpene interactions, againstM. incognita, providing alternative methods for nematode control. Copyright © 2010 Society of Chemical Industry