bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mini‐scale bioprocessing systems for highly parallel animal cell cultures
Authors: Kim Beum Jun , Diao Jinpian , Shuler Michael L. 
Published: April 2012

AbstractAnimal cells have been used extensively in therapeutic protein production. The growth of animal cells and the expression of therapeutic proteins are highly dependent on the culturing environments. A large number of experimental permutations need to be explored to identify the optimal culturing conditions. Miniaturized bioreactors are well suited for such tasks as they offer high‐throughput parallel operation and reduce cost of reagents. They can also be automated and be coupled to downstream analytical units for online measurements of culture products. This review summarizes the current status of miniaturized bioreactors for animal cell cultivation based on the design categories: microtiter plates, flasks, stirred tank reactors, novel designs with active mixing, and microfluidic cell culture devices. We compare cell density and product titer, for batch or fed‐batch modes for each system. Monitoring/controlling devices for engineering parameters such as pH, dissolved oxygen, and dissolved carbon dioxide, which could be applied to such systems, are summarized. Finally, mini‐scale tools for process performance evaluation for animal cell cultures are discussed: total cell density, cell viability, product titer and quality, substrates, and metabolites profiles. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012
Direct Crystallographic Observation of Catalytic Reactions inside the Pores of a Flexible Coordination Polymer
Authors: Das Raj Kumar , Aijaz Arshad , Sharma Manish K. , Lama Prem , Bharadwaj Parimal K. 
Published: April 2012

AbstractA new flexible porous coordination polymer (PCP), {[Gd2(L)3(dmf)4]⋅4 DMF⋅3 H2O}n (1), was synthesized under solvothermal condition by reacting [Gd(NO3)3]⋅6 H2O with the ligand 2,6,2′,6′‐tetranitro‐biphenyl‐4,4′‐dicarboxylic acid (H2L). Compound 1 had a 3D coordination polymeric structure with two types of 1D channels (A and B) that were occupied by DMF and water molecules. When crystals of 1 were separately exposed to vapors of various aromatic aldehydes, either the lattice or both the lattice and metal‐bound solvent molecules were replaced by aldehyde molecules. The aldehyde molecules inside the pores spontaneously underwent cyanosilylation and Knoevenagel condensation reactions upon exposure to vapors of trimethylsilyl cyanide and malononitrile, respectively. These reactions took place at ambient temperature and pressure. Moreover, both the reactants and the products translocated from one cavity to another. The products that occupied the cavity were expunged upon exposure to the vapors of an aldehyde. Because crystallinity was maintained during these chemical transformations, direct crystallographic observation was possible. Herein, we showed that confinement of the reactants inside the void spaces of the PCP led to the products; we also assessed catalytic activities of this PCP in bulk quantities.
Evaluation of “click” binaphthyl chiral stationary phases by liquid chromatography
Authors: Yu Hui , Yin Chenghua , Jia Cunyu , Jin Yu , Ke Yanxiong , Liang Xinmiao 
Published: April 2012

AbstractTwo “click” binaphthyl chiral stationary phases were synthesized and evaluated by liquid chromatography. Their structures incorporate S‐(−)‐1,1'‐binaphthyl moiety as the chiral selector and 1,2,3‐triazole ring as the spacer. These chiral stationary phases (CSPs) allowed the efficient resolution for a wide range of racemic BINOL derivatives, particularly for nonpolar diether derivatives and 3‐phenyl indolin‐2‐one analogs. The chromatographic data showed that the π–π interaction was crucial for enantiorecognition of these CSPs. Loss of enantioselectivity observed on CSP3, which are lacking the triazole ring linkage, indicated that the triazole ring linkage took part in the enantioseparation process, although it was remote from the chiral selector of the CSP. The substitution of the phenyl group at 6 and 6' positions can significantly improve the separation ability of the CSP. The chiral recognition mechanism was also investigated by tracking the elution orders and studying the thermodynamic parameters. Chirality 24:391–399, 2012. Copyright © 2012 Wiley Periodicals, Inc.
The functional duality of HoxB4 in hematopoietic reconstituting cells
Authors: Kaplan David , Kaye Nicholas , Liu Fangfang , Fu Pingfu , Margevicius Seunghee , Meyerson Howard J. , Lazarus Hillard M. 
Published: April 2012

AbstractTransplantation of CD34+ hematopoietic reconstituting cells (HRC) is an important treatment modality. The cells needed for clinical hematopoietic reconstitution after myeloablation most commonly derive from bone marrow which have been mobilized into the peripheral blood. The number of CD34+ cells in mobilized blood samples is used to indicate the appropriateness of transplantation although it does not evaluate the two necessary functions for successful transplantation: long‐term reconstitution mediated by cells with self‐renewing proliferation and short‐term hematopoietic differentiation mediated by progenitor cells. Using a novel high‐resolution immunophenotyping technology on a flow cytometric platform, we have assessed uniformly mobilized CD34+ cells for expression levels of 16 molecules previously associated with HRC function and sought correlations of these expression data with functional short‐term assays for colony formation that do predict successful transplantation. We found that colony‐forming units were significantly correlated with HoxB4 expression, which was explained by the number of CD34+ cells in the samples. However, analysis of colony‐forming units normalized to the CD34+ cell count revealed a significant negative correlation with HoxB4 expression. Thus, increased levels of HoxB4 enhance CD34+ cell number via self‐renewing expansion but concomitantly depreciate the capacity for short‐term differentiation per cell. Our findings demonstrate the translation of experimental findings into a clinical setting and suggest that the expression level of HoxB4 in CD34+ cells can be used as a measure of a sample's appropriateness for transplantation. © 2012 International Society for Advancement of Cytometry
Electrochemical Synthesis and Characterization of Semiconducting Ni(TCNQF4)2(H2O)2 (TCNQF4 = 2,3,5,6‐tetrafluoro‐7,7,8,8‐tetracyanoquinodimethane)
Authors: Le Thanh Hai , Nafady Ayman , Lu Jinzhen , Peleckis Germanas , Bond Alan M. , Martin Lisandra L. 
Published: April 2012

AbstractAn electrochemical technique has been used to synthesize Ni(TCNQF4)2(H2O)2 (TCNQF4 = 2,3,5,6‐tetrafluoro‐7,7,8,8‐tetracyanoquinodimethane). The method involves the reduction of solid TCNQF4 immobilized on an electrode surface in contact with Ni2+ (aq.)‐containing electrolyte. The electrochemically irreversible, but chemically reversiblesolid–solid TCNQF4/Ni(TCNQF4)2(H2O)2 interconversion process is governed by nucleation and growth kinetics and is represented by the overall reaction: 2TCNQF4 (s, electrode) + Ni2+ (aq.) + 2H2O + 2e [rlhar2] Ni(TCNQF4)2(H2O)2 (s, electrode). Thus, the formation of Ni(TCNQF4)2(H2O)2 involves the one‐electron reduction of TCNQF4 to [TCNQF4]·– coupled with an ingress of Ni2+ (aq.) from the aqueous electrolyte, while the reverse scan represents the oxidation of [TCNQF4]·– to TCNQF4 coupled with the egress of Ni2+ (aq.). Cyclic voltammograms for the TCNQF4/Ni(TCNQF4)2(H2O)2 solid–solid phase transformation are independent of the electrode material and the identity of the Ni2+ (aq.) counteranion but are strongly dependent on the concentration of Ni2+ (aq.) and the scan rate. UV/Vis, infrared, and Raman spectra confirm the presence of [TCNQF4]·– in the newly synthesized material. The composition of Ni(TCNQF4)2(H2O)2 was deduced from thermogravimetric and elemental analyses. Scanning electron microscopic images of Ni(TCNQF4)2(H2O)2 electrocrystallized onto the surface of an indium tin oxide electrode show a thin film morphology. Magnetic and conductivity data demonstrate that the complex behaves as a classical paramagnet and is a typical semiconductor with a band gap close to that of an insulator.
Attempts Directed towards the Synthesis of Intermediate (Aryne)chromium Complexes from Aryl Triflates and from (Haloarene)chromium Complexes
Authors: Werner Georg , Butenschön Holger 
Published: April 2012

AbstractThe generation of (η6‐aryne)chromium complexes as reactive intermediates was investigated in two ways. Although earlier attempts directed towards triflate eliminations from a variety of tricarbonyl(phenyl triflate)chromium complexes had failed, more electron‐rich phenyl triflate complexes were considered. This was accomplished either by substitution with two methoxy groups in the arene ligand or by replacement of one of the three carbonyl ligands of the tricarbonylchromium complex with triphenylphosphane. However, the attempted elimination still did not take place; in spite of the increased electron densities in the aromatic ligands, anionic thia‐Fries rearrangements were observed in high yields at –78 °C. As an alternative, elimination of lithium fluoride was tested. Tricarbonyl(2‐lithiofluorobenzene)chromium(0) was generated by tin/lithium exchange. After hydrolytic workup, tricarbonyl(fluorobenzene)chromium was obtained as the main product, indicating that the lithiation step had been successful. A dimeric side product provided evidence for the intermediacy of (benzyne)tricarbonylchromium.
Voltammetric Sensing of Amino Acids in the Presence of Cu(II) in Acidic and Alkaline Solutions
Authors: Pauliukaite Rasa , Pinto Edilson M. , Amine Aziz , Brett Christopher M. A. 
Published: April 2012

AbstractA number of amino acids have been determined at carbon film electrodes in the presence of copper. Strongly acidic, 0.1 M HCl, in the presence of 0.1 mM Cu(II), as well as alkaline, 0.1 M NaOH, solution permit successful measurement of individual amino acids, clearer separation between oxidation of Cu and Cu‐complexes occurring in alkaline solution. Electrochemical impedance showed that Cu(II) facilitates charge transfer, particularly in alkaline medium. Square wave voltammetry with preconcentration increased the response compared to linear sweep voltammetry. Protein hydrolysis rates were monitored through determination of amino acids produced by decomposition, injecting samples into alkaline electrolyte solution.
Long Distance Electron Transfer Across >100 nm Thick Au Nanoparticle/Polyion Films to a Surface Redox Protein
Authors: Chai Hongmei , Liu Hongyun , Guo Xihong , Zheng Dong , Kutes Yasemin , Huey Bryan D. , Rusling James F. , Hu Naifei 
Published: April 2012

AbstractGlutathione‐decorated 5 nm gold nanoparticles (AuNPs) and oppositely charged poly(allylamine hydrochloride) (PAH) were assembled into {PAH/AuNP}n films fabricated layer‐by‐layer (LbL) on pyrolytic graphite (PG) electrodes. These AuNP/polyion films utilized the AuNPs as electron hopping relays to achieve direct electron transfer between underlying electrodes and redox proteins on the outer film surface across unprecedented distances >100 nm for the first time. As film thickness increased, voltammetric peak currents for surface myoglobin (Mb) on these films decreased but the electron transfer rate was relatively constant, consistent with a AuNP‐mediated electron hopping mechanism.
Hexokinase II knockdown results in exaggerated cardiac hypertrophy via increased ROS production
Authors: Wu Rongxue , Wyatt Eugene , Chawla Kusum , Tran Minh , Ghanefar Mohsen , Laakso Markku , Epting Conrad L. , Ardehali Hossein 
Published: April 2012

AbstractHexokinase‐II (HKII) is highly expressed in the heart and can bind to the mitochondrial outer membrane. Since cardiac hypertrophy is associated with a substrate switch from fatty acid to glucose, we hypothesized that a reduction in HKII would decrease cardiac hypertrophy after pressure overload. Contrary to our hypothesis, heterozygous HKII‐deficient (HKII+/−) mice displayed increased hypertrophy and fibrosis in response to pressure overload. The mechanism behind this phenomenon involves increased levels of reactive oxygen species (ROS), as HKII knockdown increased ROS accumulation, and treatment with the antioxidant N‐acetylcysteine (NAC) abrogated the exaggerated response. HKII mitochondrial binding is also important for the hypertrophic effects, as HKII dissociation from the mitochondria resulted in de novo hypertrophy, which was also attenuated by NAC. Further studies showed that the increase in ROS levels in response to HKII knockdown or mitochondrial dissociation is mediated through increased mitochondrial permeability and not by a significant change in antioxidant defenses. Overall, these data suggest that HKII and its mitochondrial binding negatively regulate cardiac hypertrophy by decreasing ROS production via mitochondrial permeability.
INVESTIGATING ATTRIBUTE NON‐ATTENDANCE AND ITS CONSEQUENCES IN CHOICE EXPERIMENTS WITH LATENT CLASS MODELS
Authors: Lagarde Mylene 
Published: April 2012

ABSTRACTA growing literature, mainly from transport and environment economics, has started to explore whether respondents violate some of the axioms about individuals' preferences in Discrete Choice Experiments (DCEs) and use simple strategies to make their choices. One of these strategies, termed attribute non‐attendance (ANA), consists in ignoring one or more attributes. Using data from a DCE administered to healthcare providers in Ghana to evaluate their potential resistance to changes in clinical guidelines, this study illustrates how latent class models can be used in a step‐wise approach to account for all possible ANA strategies used by respondents and explore the consequences of such behaviours. Results show that less than 3% of respondents considered all attributes when choosing between the two hypothetical scenarios proposed, with a majority looking at only one or two attributes. Accounting for ANA strategies improved the goodness‐of‐fit of the model and affected the magnitude of some of the coefficient and willingness‐to‐pay estimates. However, there was no difference in the predicted probabilities of the model taking into account ANA and the standard approach. Although the latter result is reassuring about the ability of DCEs to produce unbiased policy guidance, it should be confirmed by other studies. Copyright © 2012 John Wiley & Sons, Ltd.
Microtopography, water storage and flow patterns in a fine‐textured soil under agricultural use
Authors: Bogner Christina , Mirzaei Mohammadreza , Ruy Stéphane , Huwe Bernd 
Published: April 2012

AbstractAgricultural use of soils implies tillage and often compaction and therefore influences processes on soil surface and affects infiltration of water into the subsoil. Although many studies on soil surface processes or flow patterns in soils exist, works relating both are rare in literature. We did two tracer experiments with Brilliant Blue FCF on a tilled and compacted plot and a non‐tilled one to investigate water storage on the soil surface during simulated rainfall and changes of soil microtopography, to analyse the associated flow patterns in the soil and to relate both to tillage and compaction. Our results show that storage was larger on the tilled and compacted plot than on the non‐tilled one. After tillage, transport processes above the plough pan were partly disconnected from those underneath because macropores were disrupted and buried by the tillage operation. However, preferential flow along cracks occurred on both plots and the macropores buried below the tillage pan still functioned as preferential flow paths. Therefore, we conclude that the studied soil is susceptible to deep vertical solute propagation at dry conditions when cracks are open, irrespective of tillage and compaction. Copyright © 2012 John Wiley & Sons, Ltd.
Effect of hydration on assessment of early enamel lesion using swept‐source optical coherence tomography
Authors: Nazari Amir , Sadr Alireza , Campillo‐Funollet Marc , Nakashima Syozi , Shimada Yasushi , Tagami Junji , Sumi Yasunori 
Published: April 2012

AbstractEstablishing reproducible methodologies for assessment of early enamel lesions using optical coherence tomography (OCT) appears to be challenging. This in vitro study longitudinally evaluated the subsurface enamel lesion progression after 3, 9 and 15 days by cross‐sectional scanning using 1310 nm centered swept‐source OCT (SS‐OCT) under hydrated and dry conditions. The positive difference between the depth‐integrated OCT signals at dry and hydrated conditions were calculated and adopted as dehydration parameter (DH). A linear regression was found between DH and the square root of demineralization time (R2 = 0.99). Significant differences were found in DH between sound and demineralized enamel, and between different periods of demineralization (p < 0.001). Hydration state affects the reflectivity of demineralized porous enamel, and the effect can be potentially used for assessment of early enamel lesion using OCT. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Development of a dual joystick‐controlled laser trapping and cutting system for optical micromanipulation of chromosomes inside living cells
Authors: Harsono Marcellinus S. , Zhu Qingyuan , Shi Linda Z. , Duquette Michelle , Berns Michael W. 
Published: April 2012

AbstractA multi‐joystick robotic laser microscope system used to control two optical traps (tweezers) and one laser scissors has been developed for subcellular organelle manipulation. The use of joysticks has provided a “user‐friendly” method for both trapping and cutting of organelles such as chromosomes in live cells. This innovative design has enabled the clean severing of chromosome arms using the laser scissors as well as the ability to easily hold and pull the severed arm using the laser tweezers. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ab initio study of the positronation of the CaO and SrO molecules including calculation of annihilation rates
Authors: Buenker Robert J. , Liebermann Heinz‐Peter 
Published: April 2012

AbstractAb initio multireference single‐ and double‐excitation configuration interaction calculations have been performed to compute potential curves for ground and excited states of the CaO and SrO molecules and their positronic complexes, e+CaO, and e+SrO. The adiabatic dissociation limit for the 2Σ+ lowest states of the latter systems consists of the positive metal ion ground state (M+) and the OPs complex (e+O−), although the lowest energy limit is thought to be e+M + O. Good agreement is found between the calculated and experimental spectroscopic constants for the neutral diatomics wherever available. The positron affinity of the closed‐shell X
1Σ+ ground states of both systems is found to lie in the 0.16–0.19 eV range, less than half the corresponding values for the lighter members of the alkaline earth monoxide series, BeO and MgO. Annihilation rates (ARs) have been calculated for all four positronated systems for the first time. The variation with bond distance is generally similar to what has been found earlier for the alkali monoxide series of positronic complexes, falling off gradually from the OPs AR value at their respective dissociation limits. The e+SrO system shows some exceptional behavior, however, with its AR value reaching a minimum at a relatively large bond distance and then rising to more than twice the OPs value close to its equilibrium distance. © 2012 Wiley Periodicals, Inc.
Density functional theory study of 1,2‐dioxetanone decomposition in condensed phase
Authors: da Silva Luís Pinto , da Silva Joaquim C.G. Esteves 
Published: April 2012

AbstractThe decomposition of 1,2‐dioxetanone into a CO2 molecule and into an excited state formaldehyde molecule was studied in condensed phase, using a density functional theory approach. Singlet and triplet ground and excited states were all included in the calculations. The calculations revealed a novel mechanism for the chemiluminescence of this compound. The triplet excitation can be explained by two intersystem crossings (ISCs) with the ground state, while the singlet excitation can be accounted by an ISC with the triplet state. The experimentally verified small excitation yield can then be explained by the presence of an energy barrier present in the potential energy surface of the triplet excited state, which will govern both triplet and singlet excitation. It was also found that the triplet ground state interacts with both the triplet excited and singlet ground states. A MPWB1K/mPWKCIS approach provided results in agreement with the existent literature. © 2012 Wiley Periodicals, Inc.
Remission of PTSD after victims of intimate partner violence leave a shelter
Authors: Johnson Dawn M. , Zlotnick Caron 
Published: April 2012

AbstractIntimate partner violence (IPV) is a significant public health problem associated with high rates of posttraumatic stress disorder (PTSD). Few longitudinal studies have investigated IPV‐related PTSD and we know of only 1 longitudinal study to date that has explored IPV‐related PTSD in residents of battered women's shelters. The current report describes a prospective study of IPV‐related PTSD in an initial sample of 147 residents of battered women's shelters. Baseline correlates of remission of IPV‐related PTSD (i.e., PTSD and IPV severity, loss of personal and social resources, cessation of abuse, reunion with abuser, and length of shelter stay) over a 6‐month follow‐up period were investigated. Although findings are consistent with prior research suggesting a natural recovery of PTSD in IPV‐victims, they also show that a significant number (46.8%) of women exhibit chronic PTSD. Participants whose PTSD remitted over follow‐up had at baseline less severe IPV‐related PTSD (partial η2 = .104) and fewer loss of personal and social resources (partial η2 = .095), and were less likely to reunite with their abuser after leaving the shelter than participants with chronic PTSD (3.3% and 22.4%, respectively). Clinical implications and limitations of findings are discussed.
Finding meaning in a traumatic loss: A families approach
Authors: Davis Christopher G. , Harasymchuk Cheryl , Wohl Michael J. A. 
Published: April 2012

AbstractMeaning‐making, like much of coping research, has been conceptualized and assessed as an individual‐centered phenomenon. On the premise that most traumas affect families as a whole, we assessed the extent to which meanings following a traumatic loss were congruent within families. Qualitative and quantitative data from family members coping with the loss of a family member in a mine explosion indicated moderate family congruence in meanings and global well‐being. Furthermore, greater family similarity in meaning was associated with less depressive affect in individuals (pseudoR2= .063), but was not associated with individual differences in well‐being. The research highlights the important role that families play in coping with trauma.
A pilot study of a 12‐week model of group‐based exposure therapy for veterans with PTSD
Authors: Sutherland Roy John , Mott Juliette M. , Lanier Stacey Holmes , Williams Wright , Ready David J. , Teng Ellen J. 
Published: April 2012

AbstractGroup‐based exposure therapy (GBET) is an intensive group treatment that targets posttraumatic stress disorder (PTSD) symptoms through repeated imaginal and in vivo exposure. The purpose of the present study was to assess the feasibility and acceptability of a modified 12‐week course of GBET (modified from the standard 16 weeks) and to examine its effectiveness in reducing veterans' PTSD symptoms. Participants were 10 male Operation Iraqi Freedom and Vietnam‐era veterans recruited from a PTSD specialty clinic at a large Veterans Affairs Medical Center. All participants were retained and demonstrated clinically significant reductions in PTSD symptoms (η2 = .84–.87) comparable to the standard protocol. The findings from this small sample indicate that the abbreviated 12‐week GBET protocol is a potentially effective treatment for PTSD.