bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enhancement of the hydrolysis activity of F0F1‐ATPases using 60 Hz magnetic fields
Authors: Chen Chuanfang , Cui Yuanbo , Yue Jiachang , Huo Xiaolin , Song Tao 
Published: June 2009

AbstractThe effects of extremely low frequency (ELF) magnetic fields on membrane F0F1‐ATPase activity have been studied. When the F0F1‐ATPase was exposed to 60 Hz magnetic fields of different magnetic intensities, 0.3 and 0.5 mT magnetic fields enhanced the hydrolysis activity, whereas 0.1 mT exposure caused no significant changes. Even if the F0F1‐ATPase was inhibited by N,N‐dicyclohexylcarbodiimide, its hydrolysis activity was enhanced by a 0.5 mT 60 Hz magnetic field. Moreover, when the chromatophores which were labeled with F‐DHPE were exposed to a 0.5 mT, 60 Hz magnetic field, it was found that the pH of the outer membrane of the chromatophore was unchanged, which suggested that the magnetic fields used in this work did not affect the activity of F0. Taken together, our results show that the effects of magnetic fields on the hydrolysis activity of the membrane F0F1‐ATPases were dependent on magnetic intensity and the threshold intensity is between 0.1 and 0.3 mT, and suggested that the F1 part of F0F1‐ATPase may be an end‐point affected by magnetic fields. Bioelectromagnetics 30:663–668, 2009. © 2009 Wiley‐Liss, Inc.
Chondrogenesis on BMP‐6 loaded chitosan scaffolds in stationary and dynamic cultures
Authors: Tığlı R. Seda , Gümüşderelioğlu Menemşe 
Published: June 2009

AbstractWe originally investigated the suitability of chitosan scaffolds loaded with bone morphogenetic protein 6 (BMP‐6) in both stationary and dynamic conditions for cartilage tissue engineering. In the first part of the present study, ATDC5 murine chondrogenic cells were seeded in chitosan and BMP‐6 loaded chitosan scaffolds and cultured for 28 days under static conditions. In the following part, we examined the influence of dynamic cultivation conditions over BMP‐6 loaded chitosan scaffolds by using rotating bioreactor with perfusion (RCMW™). Tissue engineered constructs were characterized by 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl‐tetrazoliumbromide (MTT) assay, scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM) and biochemical assays for glycosaminoglycans (GAG) deoxyribonucleic acid (DNA) and collagen Type II quantification. At the end of 4 weeks static incubation period high levels of GAG (21.22 mg/g dry weight), DNA amounts (1.37 mg/g dry weight) and collagen Type II amounts (1.94 µg/g dry weight) were achieved for BMP‐6 loaded chitosan scaffolds compared to chitosan scaffolds. However, the results obtained from morphological observations suggested hypertrophic differentiation of ATDC5 cells in the presence of BMP‐6 under stationary conditions. The influence of mechanical stimulation appeared significantly with differentiated cells, cultured under dynamic conditions, showing the effect of retaining their phenotypes without hypertrophy. Biotechnol. Bioeng. 2009; 104: 601–610 © 2009 Wiley Periodicals, Inc.
Exploring multiplicity conditions in enzymatic reaction networks
Authors: Otero‐Muras Irene , Banga Julio R. , Alonso Antonio A. 
Published: June 2009

AbstractIn this work, a novel algorithmic approach to detect multiplicity of steady states in enzymatic reaction networks is presented. The method exploits the structural properties of networks derived from the Chemical Reaction Network Theory. In first instance, the space of parameters is divided in different regions according to the qualitative behavior induced by the parameters in the long term dynamics of the network. Once the regions are identified, a condition for the appearance of multiplicities is checked in the different regions by solving a given optimization problem. In this way, the method allows the characterization of the whole parameter space of biochemical networks in terms of the appearance or not of multistability. The approach is illustrated through a well‐known case of enzymatic catalysis with substrate inhibition. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Maximizing power production in a stack of microbial fuel cells using multiunit optimization method
Authors: Woodward Lyne , Tartakovsky Boris , Perrier Michel , Srinivasan Bala 
Published: June 2009

AbstractThis study demonstrates real‐time maximization of power production in a stack of two continuous flow microbial fuel cells (MFCs). To maximize power output, external resistances of two air–cathode membraneless MFCs were controlled by a multiunit optimization algorithm. Multiunit optimization is a recently proposed method that uses multiple similar units to optimize process performance. The experiment demonstrated fast convergence toward optimal external resistance and algorithm stability during external perturbations (e.g., temperature variations). Rate of the algorithm convergence was much faster than in traditional maximum power point tracking algorithms (MPPT), which are based on temporal perturbations. A power output of 81–84 mW/LA (A = anode volume) was achieved in each MFC. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Robust parameter estimation during logistic modeling of batch and fed‐batch culture kinetics
Authors: Goudar Chetan T. , Konstantinov Konstantinov B. , Piret James M. 
Published: June 2009

AbstractMethods for robust logistic modeling of batch and fed‐batch mammalian cell cultures are presented in this study. Linearized forms of the logistic growth, logistic decline, and generalized logistic equation were derived to obtain initial estimates of the parameters by linear least squares. These initial estimates facilitated subsequent determination of refined values by nonlinear optimization using three different algorithms. Data from BHK, CHO, and hybridoma cells in batch or fed‐batch cultures at volumes ranging from 100 mL–300 L were tested with the above approach and solution convergence was obtained for all three nonlinear optimization approaches for all data sets. This result, despite the sensitivity of logistic equations to parameter variation because of their exponential nature, demonstrated that robust estimation of logistic parameters was possible by this combination of linearization followed by nonlinear optimization. The approach is relatively simple and can be implemented in a spreadsheet to robustly model mammalian cell culture batch or fed‐batch data. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Characterization and design of chemically selective cationic displacers using a robotic high‐throughput screen
Authors: Morrison Christopher J. , Cramer Steven M. 
Published: June 2009

AbstractA robotic high‐throughput displacer screen was developed and employed to identify chemically selective displacers for several protein pairs in cation exchange chromatography. This automated screen enabled the evaluation of a wide range of experimental conditions in a relatively short period of time. Displacers were evaluated at multiple concentrations for these protein pairs, and DC‐50 plots were constructed. Selectivity pathway plots were also constructed and different regimes were established for selective and exclusive separations. Importantly, selective displacement was found to be conserved for multiple protein pairs, demonstrating the technique to be applicable for a range of protein systems. Although chemically selective displacers were able to separate protein pairs that had similar retention in ion exchange but different surface hydrophobicities, they were not able to distinguish protein pairs with similar surface hydrophobicities. This corroborates that displacer‐protein hydrophobic interactions play an important role for this class of selective displacers. Important functional group moieties were established and efficient displacers were identified. These results demonstrate that the design of chemically selective displacers requires a delicate balance between the abilities to displace proteins from the resin and to bind to a selected protein. The use of robotic screening of displacers will enable the extension of chemically selective displacement chromatography beyond hydrophobic displacer‐protein interactions to other secondary interactions and more selective displacement systems. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Second international conference on accelerating biopharmaceutical development
Authors: Reichert Janice M. , Jacob Nitya M. , Amanullah Ashraf 
Published: June 2009

AbstractThe Second International Conference on Accelerating Biopharmaceutical Development was held in Coronado, California. The meeting was organized by the Society for Biological Engineering (SBE) and the American Institute of Chemical Engineers (AIChE); SBE is a technological community of the AIChE. Bob Adamson (Wyeth) and Chuck Goochee (Centocor) were co‐chairs of the event, which had the theme “Delivering cost‐effective, robust processes and methods quickly and efficiently.” The first day focused on emerging disruptive technologies and cutting‐edge analytical techniques. Day two featured presentations on accelerated cell culture process development, critical quality attributes, specifications and comparability, and high throughput protein formulation development. The final day was dedicated to discussion of technology options and new analysis methods provided by emerging disruptive technologies; functional interaction, integration and synergy in platform development; and rapid and economic purification process development. © This meeting report was written for and published by Landes Bioscience in the journal, mAbs. Reichert JM, Jacob N, Amanullah A. Second International Conference on Accelerating Biopharmaceutical Development: March 9–12, 2009, Coronado, CA USA. mAbs 2009 1(3); http://www. landesbioscience.com/journals/mabs/article/8491 Biotechnol. Prog., 2009
Heterohexanuclear (Cu3Fe3) Complexes of Substituted Hexaazatrinaphthylene (HATN) Ligands: Twofold BF4− Association in the Solid and Stepwise Oxidation (3e) or Reduction (2e) to Spectroelectrochemically Characterized Species
Authors: Roy Sayak , Sarkar Biprajit , Duboc Carole , Fiedler Jan , Sarper Orkan , Lissner Falk , Mobin Shaikh M. , Lahiri Goutam Kumar , Kaim Wolfgang 
Published: June 2009

AbstractNew tris(ferrocenylcopper) compounds [(μ3‐dqp){Cu(dppf)}3][X]3 (dppf=1,1′‐bis(diphenylphosphinoferrocene), dqp=hexamethyl‐, hexachloro‐ or un‐substituted diquinoxalino[2,3‐a:2′,3′‐c]phenazine=hexaazatrinaphthylene (HATN), X−=BF4− or PF6−) undergo at least two different, reversible one‐electron reductions and three very closely spaced one‐electron oxidations. While the latter are attributed to the stepwise ferrocene→ferrocenium conversions, the first electron addition occurs in the ligand bridge to yield EPR detectable radical complexes. X‐band EPR measurements at 9.5 GHz showed a partially resolved hyperfine structure, while high‐frequency EPR measurements at 95 or 115 GHz revealed a small but variable axial g tensor anisotropy. All reversible steps were investigated by optically transparent thin‐layer electrode (OTTLE) spectroelectrochemistry (UV/Vis/NIR regions), revealing very low energy transitions for the reduced forms in agreement with the frontier MO arrangement. A crystal structure of the compound with unsubstituted dqp shows notable deviation from the trigonal symmetry and the close association of two tetrafluoroborate anions with the complex trication along the quasi‐trigonal axis to yield [(μ3‐dqp){Cu(dppf)}3(BF4)2]BF4.
Nucleic Acid Templated Reactions: Consequences of Probe Reactivity and Readout Strategy for Amplified Signaling and Sequence Selectivity
Authors: Grossmann Tom N. , Seitz Oliver 
Published: June 2009

AbstractMaking the right signals: Reactions in which the DNA target acts as a catalyst allow amplified signaling in the detection of DNA. The reactivity of the peptide nucleic acid (PNA) probes determines whether a given probe set provides high sensitivity or high selectivity. The careful adjustment of reactivity, probe affinity, and the use of a product‐selective readout method allows improvements in the sensitive analyses of single‐base mutations in DNA with little background interference.magnified imageDNA‐ and RNA‐templated chemical reactions can serve as a diagnostic means for the detection of nucleic acids. Reaction schemes that allow amplified detection are of high interest for polymerase chain reaction (PCR)‐free DNA and RNA diagnosis. These reactions typically draw upon the catalytic activity of the template, which is able to trigger the conversion of many signaling molecules per template molecule. However, the design of reactive probes that allow both sensitive and selective nucleic acid detection is a challenge and requires insight into three major parameters: a) reactivity of functional groups involved, b) affinity of probes for the template, and c) the readout system. In this study we used peptide nucleic acid (PNA)‐based probes to investigate in detail the signaling power and the selectivity of a transfer reaction derived from a native chemical ligation. We show that subtle variations of the thioesters involved had a tremendous impact on the sensitivity and selectivity of the reaction system. The results suggest that reactions at turnover conditions require low rates of non‐templated reaction pathways to provide high target selectivity and sensitivity. On the other hand, very high rates of templated reactions should be avoided to allow mismatched probe–template complexes to dissociate prior to bond formation. Furthermore, the temperature dependence of the DNA‐catalyzed transfer reaction was studied and provided insight into crucial strand‐exchange processes. Further improvements of selective signaling were achieved through a new readout based on pyrene‐transfer reactions. This method reduces background signals and enables significant increases in the signaling rates compared with previous fluorescence‐based methods.
Multifunctional Hydroxyapatite Nanofibers and Microbelts as Drug Carriers
Authors: Hou Zhiyao , Yang Piaoping , Lian Hongzhou , Wang Lili , Zhang Cuimiao , Li Chunxia , Chai Ruitao , Cheng Ziyong , Lin Jun 
Published: June 2009

AbstractLuminescent, mesoporous, and bioactive europium‐doped hydroxyapatite (HAp:Eu3+) nanofibers and microbelts have been prepared by a combination of sol–gel and electrospinning processes with a cationic surfactant as template. The obtained multifunctional hydroxyapatite nanofibers and microbelts, which have mesoporous structure and red luminescence, were tested as drug carriers by investigating their drug‐storage/release properties with ibuprofen (IBU) as model drug. X‐ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy (TEM), high‐resolution (HR) TEM, FTIR spectroscopy, N2 adsorption/desorption, photoluminescence (PL) spectra, and UV/Vis spectroscopy were used to characterize the structural, morphological, textural, and optical properties of the resulting samples. The results reveal that the multifunctional hydroxyapatites exhibit irregular mesostructure, and have fiberlike and beltlike morphologies with sizes of several hundred nanometers in width and several millimeters in length. The IBU‐loaded HAp:Eu3+ system shows red luminescence of Eu3+ (5D0–7F0,1,2) under UV irradiation and controlled release of IBU. In addition, the emission intensity of Eu3+ in the drug carrier system varies with the released amount of IBU, and thus drug release can be easily tracked and monitored by the change in luminescence intensity.
Modulated Morphology in the Self‐Organization of a Rectangular Amphiphile
Authors: García Fátima , Fernández Gustavo , Sánchez Luis 
Published: June 2009

AbstractMolecular construction: Concentration and/or solvent polarity changes modify the subtle balance of the attractive non‐covalent forces involved in the self‐assembly of a rectangular amphiphile. These changes allow the construction of supramolecular architectures ranging from hollow vesicles of different sizes to toroids and wire‐like micelles (see figure).magnified imageThe rectangular oligo(phenylene ethynylene) amphiphile 1 has been synthesized to investigate its self‐assembling features in solution and onto surfaces. Concentration‐dependent and variable‐temperature NMR experiments firstly demonstrate the influence of the solvent in the stabilization of the non‐covalent forces involved in the association of 1, namely, π–π stacking interactions between the aromatic fragments and van der Waals, hydrogen‐bonding and/or solvophobic forces between the triethyleneglycol chains. This subtle balance of non‐covalent interactions also conditions the thermodynamics of the self‐assembly process and concentration‐dependent UV/Vis investigations show a linear correlation between the polarity of the solvent and the Ka values (Ka≈5.2×105 M−1 for CH3CN/H2O mixtures and 4.4×104 M−1 for benzene). Moreover, these UV/Vis studies prove the organization of this compound following the indefinite self‐association model. Microscopy techniques reveal that the morphology and dimensionality of the assemblies formed from 1 can be finely modulated. Although polar solvents yield hollow vesicles or toroidal 3D objects, depending upon concentration, the utilization of non‐polar benzene results in the formation of unimolecular wires that can grow to form networks upon increasing concentration. These findings support the direct relationship existing between the self‐assembling features of this amphiphile in solution and onto surfaces.
Synthesis and Reactivity of Functionalized Binary and Ternary Thiometallate Complexes [(RT)4S6], [(RSn)3S4]2−, [(RT)2(CuPPh3)6S6], and [(RSn)6(OMe)6Cu2S6]4− (R=C2H4COOH, CMe2CH2COMe; T=Ge, Sn)
Authors: Fard Zohreh Hassanzadeh , Xiong Lin , Müller Christian , Hołyńska Małgorzata , Dehnen Stefanie 
Published: June 2009

AbstractCaged chalcogens: A series of novel, functionalized TnSm cages (T=Ge, Sn; n/m=4:6, 3:4) with terminal COO(H) or COMe groups were synthesized and show further reactivity toward CuI complexes (an example of which is shown here) and to hydrazines. This led to the generation of functionalized Cu/T/S clusters or the formation of Schiff bases at the CO groups, respectively, with or without further fragmentation of the T/S core.magnified imageA series of compounds comprising functionalized thiometallate cages [(RT)4S6] (R terminated by COO(H) or COR groups), based on adamantane (T=Ge) or double‐decker (T=Sn) type structures or [(RSn)3S4]2− anionic defect heterocubanes were synthesized and their reactions with 1) transition‐metal compounds and 2) hydrazine derivatives were explored. Hence it was possible to generate functionalized ternary CuSnS or CuGeS clusters and to transfer COR ligands into CR(N‐NH2) or CR(N‐NHPh) terminal groups, respectively. The report provides the proof‐of‐principle for a directed functionalization and derivatization of chalcogenidometallate cages with respect to the formation of chalcogenidometallate–organic hybrid compounds containing M/E semiconductor nodes, as an alternative to the so far most prominent M/O combination in metal–organic frameworks. DFT investigations deliver further insight in the peculiarities of Ge/S versus Sn/S precursors and their products.
1,2,4‐Diazaphospholide Complexes of Tin(II): From Nitride Stannylene to Stannylenated Ammonium Ions
Authors: Pi Chengfu , Elguero José , Wan Li , Alkorta Ibon , Zheng Wenjun , Weng Linhong , Chen Zhenxia , Wu Limin 
Published: June 2009

AbstractTin knows its oniums! An unusual nitride tetrastannylene and a stannylenated ammonium ion stabilized by a samarium tetradiazaphospholido counterion are the first examples of a tris(organostannylenyl)amine derivative and a divalent tin coordinate onium ion that incorporates 1,2,4‐diazaphospholide ligand (see figure).magnified image
ChemInform Abstract: Site Occupation Reversal in the C14 Laves Phase Nb(Cr1‐xCox)2.
Authors: Kerkau Alexander , Gruener Daniel , Ormeci Alim , Prots Yurii , Borrmann Horst , Schnelle Walter , Bischoff Ewald , Grin Yurii , Kreiner Guido 
Published: June 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.
ChemInform Abstract: Photoluminescence Properties of Eu3+: MgAl2O4 Powder Phosphor.
Authors: Omkaram I. , Rao B. Vengala , Buddhudu S. 
Published: June 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.
ChemInform Abstract: [Cu(H2O)(C5H14N2)2] [VO3]2 — A Metavanadate Containing Right‐ and Left‐Handed Helical Chains.
Authors: Wutkowski Adam , Naether Christian , Bensch Wolfgang 
Published: June 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.
ChemInform Abstract: A New Mixed‐Valence Ferrite with a Cubic Structure, YBaFe4O7: Spin‐Glass‐Like Behavior.
Authors: Caignaert V. , Abakumov A. M. , Pelloquin D. , Pralong V. , Maignan A. , Van Tendeloo G. , Raveau B. 
Published: June 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.
ChemInform Abstract: Tetrahedral Cobalt(II) and Zinc(II) Chloride with Tetravanadate Through a Tripod Coordination Mode.
Authors: Kurata Taisei , Hayashi Yoshihito , Isobe Kiyoshi 
Published: June 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.
ChemInform Abstract: Rhodium(I)‐Catalyzed Intramolecular Carbonylative [2 + 2 + 1] Cycloaddition of Bis(allene)s: Bicyclo[6.3.0]undecadienones and Bicyclo[5.3.0]decadienones.
Authors: Inagaki Fuyuhiko , Narita Syu , Hasegawa Takuma , Kitagaki Shinji , Mukai Chisato 
Published: June 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.
ChemInform Abstract: NHC‐Catalyzed Ring Expansion of Oxacycloalkane‐2‐carboxaldehydes: A Versatile Synthesis of Lactones.
Authors: Wang Li , Thai Karen , Gravel Michel 
Published: June 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.
ChemInform Abstract: Tetra‐n‐butylammonium Fluoride‐Catalyzed Eschenmoser—Claisen [3,3]‐Sigmatropic Rearrangement.
Authors: Lingam V. S. Prasada Rao , Vinodkumar Ramanatham , Mukkanti Khagga , Thomas Abraham , Gopalan Balasubramanian 
Published: June 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.