bluuebunny/crossref_metadata_2025_split huggingface dataset:
Propioin synthesis using thiamine diphosphate‐dependent enzymes
Authors: Mikolajek Renaud J. , Spiess Antje C. , Pohl Martina , Büchs Jochen 
Published: January 2009

AbstractBenzaldehyde lyase (BAL, EC 4.1.2.38) from Pseudomonas fluorescens and benzoylformate decarboxylase (BFD, EC 4.1.1.7) from Pseudomonas putida are thiamine diphosphate‐dependent enzymes. These enzymes share a common tetrameric structure and catalyze various CC‐bond forming and breaking reactions. Here we describe a detailed study of the asymmetric synthesis of propioin from propanal catalyzed by BAL or BFD in aqueous solution in a batch reactor. Both enzymes are deactivated in the presence of high concentration of propanal. Compared to BAL, BFD is more stable under reaction conditions as well as during storage. The kinetic studies showed a typical Michaelis‐Menten kinetic for BAL with a maximal specific reaction rate of 26.2 U/mg and an unusually high KM of 415 mM, whereas the v/[S]‐plot for BFD is almost linear in the concentration range (100–1500 mM) investigated. Both enzymes produce propioin with opposite enantiomeric excess: BAL produced the (S)‐propioin (ee of 35%), whereas BFD yielded the (R)‐enantiomer (ee of 67%). © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Effect of moderate electric field frequency and growth stage on the cell membrane permeability of Lactobacillus acidophilus
Authors: Loghavi Laleh , Sastry Sudhir K. , Yousef Ahmed E. 
Published: January 2009

AbstractChanges in growth kinetics and metabolic activity of microorganisms under the presence of a moderate electric field (MEF) have been hypothesized as being due to temporary permeabilization of cell membranes. We investigated herein the effects of frequency and growth stage on cell membrane permeabilization of Lactobacillus acidophilus OSU 133 during MEF fermentation. Cells were stained with two fluorescent nucleic acid stains: the green, nonselective, cell membrane permeable SYTO 9, and the red, cell membrane impermeable propidium iodide (PI). Fluorescence exhibition post‐treatment was assessed using fluorescence microscopy. Total plate counting was done to determine whether or not the permeabilized population represented live cells. Fermentation treatments investigated were conventional (control) and MEF (2 V/cm, 45, 60, 1,000, 10,000 Hz) at 30°C. Studies were conducted at 45 Hz for lag, exponential, and stationary phases of growth. Low frequency MEF treated cells exhibited significantly greater numbers of red cell counts than conventional treatments; further, no significant differences existed in viable counts between MEF and conventional treatments, suggesting that the red counts represent permeabilized live cells. MEF treatments at the early stage of bacterial growth at 45 Hz exhibited the maximum permeabilization followed by treatments at 60 Hz. MEF treated samples at frequencies higher than 60 Hz did not exhibit red fluorescence. Cells at lag phase showed the greatest susceptibility to permeabilization followed by those at exponential phase. No evidence of electroporation was observed during the stationary phase. To our knowledge, these observations provide the first evidence that cell membrane permeabilization occurs under the presence of electric fields as low as those under MEF. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Alkali‐catalyzed low temperature wet crosslinking of plant proteins using carboxylic acids
Authors: Reddy Narendra , Li Ying , Yang Yiqi 
Published: January 2009

AbstractWe report the development of a new method of alkali‐catalyzed low temperature wet crosslinking of plant proteins to improve their breaking tenacity without using high temperatures or phosphorus‐containing catalysts used in conventional poly(carboxylic acid) crosslinking of cellulose and proteins. Carboxylic acids are preferred over aldehyde‐containing crosslinkers for crosslinking proteins and cellulose because of their low toxicity and cost and ability to improve the desired properties of the materials. However, current knowledge in carboxylic acid crosslinking of proteins and cellulose requires the use of carboxylic acids with at least three carboxylic groups, toxic phosphorous‐containing catalysts and curing at high temperatures (150–185°C). The use of high temperatures and low pH in conventional carboxylic acid crosslinking has been reported to cause substantial strength loss and/or undesired changes in the properties of the crosslinked materials. In this research, gliadin, soyprotein, and zein fibers have been crosslinked with malic acid, citric acid, and butanetetracarboxylic acid to improve the tenacity of the fibers without using high temperatures and phosphorus‐containing catalysts. The new method of wet crosslinking using carboxylic acids containing two or more carboxylic groups will be useful to crosslink proteins for various industrial applications. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Design and characterization of a microfluidic packed bed system for protein breakthrough and dynamic binding capacity determination
Authors: Shapiro Michael S. , Haswell Steve J. , Lye Gary J. , Bracewell Daniel G. 
Published: January 2009

AbstractA 1.5 μL ion exchange chromatography column to accommodate resins used for biopharmaceutical processing has been designed to produce breakthrough curves and to quantify dynamic and maximum protein binding capacities. Channels within a glass chip were fabricated using photolithography and isotropic etching. The design includes a 1 cm long microfluidic column in which compressible, polydispersed porous agarose beads (70 μm mean diameter) were packed using a keystone method where particles aggregate in a narrow channel. The depth of the column is such that two bead layers exist. The fabrication technique used forms Cartesian geometries as opposed to circular cross sections found in standard columns. The voidage was therefore higher than standard values when measured by 3D confocal microscopy. In conjunction with microscopic techniques, the column allows visualization of events within the bed such as adsorption profiles that would otherwise be difficult to observe. In this work, the binding of fluorescently labeled protein during isocratic loading was used to generate breakthrough from the microcolumn. Useful breakthrough curves were achieved using mobile phase velocities from 60 to 270 cm h−1. Calculated dynamic binding capacities were compared well with previously published data on conventional scale columns. The microfluidic chromatography column described here thus allows study of process scale chromatography behavior at scales 20,000 times smaller than in current practice. The work described in this article is representative of the proof of principle of a potentially powerful tool for the generation of microfluidic process bed data for the biopharmaceutical industry. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Virtual reality for future workforce preparation
Authors: Smith Shana S. , Saunders Kevin P. 
Published: January 2009

AbstractThis study discusses how the use of virtual reality technology impacts academic and industry needs. Results and recommendations from interviews concerning engineering design curricula are presented for two major computer‐aided design companies. The results described show that virtual reality technology has significant impacts on academia and industry and that there are also significant interactions and relationships between the two entities. Implementation techniques and responses from students, faculty, and industry are presented. The article concludes with recommendations for current practice and areas for future research, which will promote effective use of virtual reality in engineering education. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 17: 429–434, 2009; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20211
Efficient development of a web‐based environmental testing system using a novel two‐layer software architecture
Authors: Lai Yuan‐Cheng , Lin Jian‐Wei 
Published: January 2009

AbstractThis work proposes a two‐layer software architecture and design considerations for the efficient development of a Web‐based environmental testing system. The efficiency of developing such a system can be significantly improved since the upper layer, called the Web application, can immediately employ the uniform interface and follow the call flow provided in the lower layer, called the COM component. The COM component particularly addresses the integration of various instrument control mechanisms and the concurrency issue, while the Web application addresses database, security, modularity, and graphic user interface (GUI) issues. Moreover, based on the proposed software architecture and design considerations, a Web‐based environmental testing system, called the Web‐based Automatic Measurement System (Web AMS), is developed to validate the efficiency of this architecture and address the above issues. The proposed synchronization mechanism, not only enables many experiments to share one Digital Multi‐Meter (DMM) simultaneously, but also allows many remote clients to monitor the status of operating devices in a progressing experiment concurrently. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 17: 412–421, 2009; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20238
Prevention of child abuse and neglect and improvements in child development
Authors: Christoffersen Mogens Nygaard , DePanfilis Diane 
Published: January 2009

AbstractThe aim of the study was to evaluate the implementation of a section in the Danish Social Assistance Act which encourages local authorities to offer families services in order to support children at risk of child maltreatment. The specific purpose of the present paper is to answer the question: Will the socio‐psychological development of children known to social services be improved when abuse and neglect are reduced? A sample of 1,138 children was drawn at random from new social services cases starting in 1998. Subsequently, about 80 per cent were evaluated by local caseworkers on the basis of a standardised questionnaire covering a period of four years. The most damaging family conditions seemed to be psychological maltreatment, physical/sexual abuse and neglect. Maltreated children were more often in a depressed state, unhappy, socially isolated, or they had an eating disorder, inadequate or under‐nutrition, suicidal tendencies, lack of concentration, or disturbed behaviour, compared to those children who were not exposed to abuse and neglect. If parental behaviour improved, effects on children's well‐being were also observed and positive changes in children's socio‐psychological development were identified. The questionnaire explored the impact of various interventions, including services geared to strengthen the child's network, but results indicated that the child displayed reduced risk of reactive symptoms only when parental behaviour improved and abuse and neglect were reduced. Copyright © 2009 John Wiley & Sons, Ltd.
The effortful citizen: Discursive social psychology and welfare reform
Authors: Gibson Stephen 
Published: January 2009

AbstractThe present study applies a broadly discursive approach to the representation of welfare reform and unemployment through an analysis of the deployment of an interpretative repertoire of effortfulness in posts to an internet discussion forum. It is argued that when posters construct versions of unemployed people or welfare recipients as characterized by ‘laziness’ or lack of ‘effort’ the attribution of responsibility for unemployment is frequently not the only piece of discursive business being attended to. In addition, posters attend to issues of their own accountability and, significantly, the accountability of the government or welfare system itself for the extent to which welfare recipients are formally held to account. It is argued that this approach extends previous social psychological work on the explanation of unemployment insofar as it pays attention to the context‐specific functions performed by such explanations. Moreover, in orienting to the welfare system as having a responsibility to hold welfare recipients to account, posters are drawing on a set of discursive resources which essentially treat the government of individual psychology as a legitimate function of the welfare system. Copyright © 2009 John Wiley & Sons, Ltd.
Percutaneous closure of a postinfarction ventricular septal defect and an iatrogenic left ventricular free‐wall perforation using two Amplatzer muscular VSD occluders
Authors: Eshtehardi Parham , Garachemani Ali , Meier Bernhard 
Published: January 2009

AbstractA 83‐year‐old woman underwent percutaneous closure of postinfarction ventricular septal defect following anteroseptal myocardial infarction and percutaneous coronary intervention with stent implantation of the left anterior descending coronary artery. Postinfarction percutaneous ventricular septal defect closure was initially complicated by an iatrogenic left ventricular free‐wall perforation. Both defects were closed using two Amplatzer muscular VSD occluders during the same session. © 2009 Wiley‐Liss, Inc.
In‐ambulance abciximab administration in STEMI patients prior to primary PCI is associated with smaller infarct size, improved LV function and lower incidence of heart failure: Results from the Leiden MISSION! acute myocardial infarction treatment optimization program
Authors: Hassan Ayman K. M. , Liem Su San , van der Kley Frank , Bergheanu Sandrin C. , Wolterbeek Ron , Bosch Jan , Bootsma Marianne , Zeppenfeld Katja , van der Laarse Arnoud , Atsma Douwe E. , Jukema J. Wouter , Schalij Martin J. 
Published: January 2009

AbstractObjectives:Our aim was to evaluate the effects of early abciximab administration in the ambulance on immediate, short, and long term outcomes.Background:Early abciximab administration before primary percutaneous coronary intervention (PPCI) for ST‐segment elevation myocardial infarction (STEMI) is recommended in practice guidelines. However, optimal timing of administration remains indistinct.Methods:Within a fixed protocol for PPCI, December 2006 was the cut‐off point for this prospective study. A total of 179 consecutive patients with STEMI were enrolled, 90 patients received abciximab bolus in the hospital (in‐hospital group), and 89 patients received abciximab bolus in the ambulance (in‐ambulance group).Results:The two groups were comparable for baseline and angiographic characteristics. The in‐ambulance group received abciximab within the golden period (median 63 min). The infarct related artery (IRA) patency at onset of the PCI was four times higher in the in‐ambulance group compared to in‐hospital group (odds ratio = 4.9, 95% CI 2.4–10.1). Enzymatic infarct size was smaller in the in‐ambulance group (cumulative 48‐h CK release 8011 vs. 11267 U/L, P = 0.004). This was associated with higher left ventricular ejection fraction (LVEF) at 90 days post‐PPCI measured by myocardial scintigraphy (59% vs. 54%, P = 0.01), and lower incidence of heart failure through a median of 210 days of clinical follow‐up (3% vs.11%, P = 0.04).Conclusion:Early abciximab administration in the ambulance significantly improves early reperfusion in STEMI patients treated with PPCI. Moreover this is associated with a smaller infarct size, improved LV function and a lower risk of heart failure on clinical follow‐up. © 2009 Wiley‐Liss, Inc.
Novel method for delivering the Amplatzer® muscular VSD occluder in a patient with double outlet right ventricle after bidirectional Glenn procedure and pulmonary artery band
Authors: Bocks Martin L. , Armstrong Aimee K. 
Published: January 2009

AbstractWe report the first use of bilateral femoral venovenous rail creation for the delivery of an Amplatzer® Muscular Ventricular Septal Defect Occluder in a patient with a large mid‐to‐apical muscular ventricular septal defect before Rastelli operation. The presence of a right‐sided bidirectional Glenn shunt, a banded main pulmonary artery, and double outlet right ventricle anatomy precluded the use of standard delivery techniques. The patient underwent successful transcatheter device placement followed by Rastelli operation on the following day. © 2009 Wiley‐Liss, Inc.
Tetraalkylammonium Salts of Weakly Coordinating Aluminates: Ionic Liquids, Materials for Electrochemical Applications and Useful Compounds for Anion Investigation
Authors: Raabe Ines , Wagner Katrin , Guttsche Kristin , Wang Mingkui , Grätzel Michael , Santiso‐Quiñones Gustavo , Krossing Ingo 
Published: January 2009

AbstractWeak and robust? Tetraalkylammonium salts of weakly coordinating fluorinated alkoxyaluminates are easily accessible, chemically robust materials that show interesting physico‐chemical properties like low melting points, high electrochemical stability and electric conductivity in weakly polar solvents such as CH2Cl2, Ph‐F and toluene.magnified imageIn this study, we investigated the tetraalkylammonium salts of the weakly coordinating fluorinated alkoxyaluminates [pftb]− ([Al(O(C(CF3)3)4]−), [hfip]− ([Al(OC(H)(CF3)2)4]−) and [hftb]− ([Al(OC(CH3)(CF3)2)4]−) in order to obtain information on their undisturbed spectral and structural properties, as well as to study their electrochemical behavior (i.e., conductivities in non‐polar solvents and electrochemical windows). Several of the compounds qualify as ionic liquids with melting points as low as 42 °C for [NBu4]+[hfip]−. Simple and almost quantitative metathesis reactions yielding these materials in high purity were developed. These [NR4]+ salts serve as model compounds for undisturbed anions and their vibrational spectra—together with simulated spectra based on quantum chemical DFT calculations—were used for the clear assignment of the anion bands. Besides, the ion volumes of the anions (Vion([pftb]−)=0.736 nm3, Vion([hftb]−)=0.658 nm3, Vion([hfip]−)=0.577 nm3) and their decomposition pathways in the mass spectrometric measurements have been established. The salts are highly soluble in non‐polar solvents (up to 1.09 mol L−1 are possible for [NBu4]+[hftb]− in CH2Cl2 and 0.41 mol L−1 for [NBu4]+[hfip]− in CHCl3) and show higher molar conductivities if compared to [NBu4]+[PF6]−. The electrochemical windows of CH2Cl2, CH3CN and 1,2‐F2C6H4 using the [NBu4]+ aluminate electrolytes are up to +0.5 V/−0.7 V larger than those using the standard [NBu4]+[PF6]−.
Aluminium Speciation in 1‐Butyl‐1‐Methylpyrrolidinium Bis(trifluoromethylsulfonyl)amide/AlCl3 Mixtures
Authors: Rocher Nathalie M. , Izgorodina Ekaterina I. , Rüther Thomas , Forsyth Maria , MacFarlane Douglas R. , Rodopoulos Theo , Horne Michael D. , Bond Alan M. 
Published: January 2009

AbstractAluminium speciation: Aluminium speciation in NTf2 ionic liquids has a strong influence on its electrodeposition from the liquid mixture. This work probed the nature of these species and proposes that the electroactive species involved are either [AlCl3(NTf2)]− or [AlCl2(NTf2)2]− (e.g., see figure).magnified imageElectrodeposition of aluminium is possible from solutions of AlCl3 dissolved in the 1‐butyl‐1‐methylpyrrolidinium bis(trifluoromethylsulfonyl)amide (C4mpyrNTf2) ionic liquid. However, electrodeposition is dependant on the AlCl3 concentration as it only occurs at concentrations >1.6 mol L−1. At these relatively high AlCl3 concentrations the C4mpyrNTf2/AlCl3 mixtures exhibit biphasic behaviour. Notably, at 1.6 mol L−1 AlCl3, aluminium can only be electrodeposited from the upper phase. Conversely, we found that at 3.3 mol L−1 aluminium electrodeposition can only occur from the lower phase. The complex chemistry of the C4mpyrNTf2/AlCl3 system is described and implications of aluminium speciation in several C4mpyrNTf2/AlCl3 mixtures, as deduced from Raman and 27Al NMR spectroscopic data, are discussed. The 27Al NMR spectra of the C4mpyrNTf2/AlCl3 mixtures revealed the presence of both tetrahedrally and octahedrally coordinated aluminium species. Raman spectroscopy revealed that the level of uncoordinated NTf2− anions decreased with increasing AlCl3 concentration. Quantum chemical calculations using density functional and ab initio theory were employed to identify plausible aluminium‐containing species and to calculate their vibrational frequencies, which in turn assisted the assignment of the observed Raman bands. The data indicate that the electroactive species involved are likely to be either [AlCl3(NTf2)]− or [AlCl2(NTf2)2]−.
Self‐Organization, Optical, and Electrical Properties of α‐Quinquethiophene–Dinucleotide Conjugates
Authors: Alesi Silvia , Brancolini Giorgia , Viola Ilenia , Capobianco Massimo Luigi , Venturini Alessandro , Camaioni Nadia , Gigli Giuseppe , Melucci Manuela , Barbarella Giovanna 
Published: January 2009

AbstractBiodriven self‐organization of α‐quinquethiophene (t5): Cast films of 5′TA3′‐t5 are electroactive, photoluminescent, and chiral. Their growth is not directed by intermolecular Watson–Crick hydrogen bonding between the A⋅⋅⋅T moieties of interacting molecules, but is governed by intra‐ and intermolecular thiophene–nucleobase stacking interactions.magnified imageThe synthesis and properties of 5′TA3′‐t5 (8 a) and 5′CG3′‐t5 (8 b) conjugates, in which the self‐complementary dinucleotides TA and CG are covalently bound to the central ring of α‐quinquethiophene (t5), are described. According to molecular mechanics calculations, the preferred conformation of both 8 a and 8 b is that with the dinucleotide folded over the planar t5 backbone, with the nucleobases facing t5 at stacking distance. The calculations show that the aggregation process of 8 a and 8 b is driven by a mix of nucleobase‐thiophene interactions, hydrogen bonding between nucleobases (non Watson–Crick (W&C) in TA, and W&C in CG), van der Waals, and electrostatic interactions. While 8 b is scarcely soluble in any solvents, 8 a is soluble in water, indicating that the aggregates of the former are more stable than those of the latter. Microfluidic‐induced self‐assembly studies of 8 a showed the formation of lamellar, spherulitic, and dendritic supramolecular structures, depending on the concentration and solvent evaporation time. The self‐assembled structures displayed micrometer dimensions in the xy plane of the substrate and nanometer dimensions in the z direction. Spatially resolved confocal microscopy and spectroscopy showed that the aggregates were characterized by intense fluorescence emission. Cast films of 8 a from water solutions showed chirality transfer from the dinucleotide to t5. The hole mobility of the cast films of 8 a was estimated using a two‐electrode device under high vacuum and found to be up to two orders of magnitude greater than those previously measured for dinucleotide–quarterthiophene conjugates under the same experimental conditions.