bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Comparison of Density‐Functional Theory and HartreeFock Modeling of Organolithium Equilibria
Authors: Streitwieser Andrew , Leong Yew Hung 
Published: October 2012

AbstractExperimental values for a number of organolithium equilibria in THF solution expressed as pK values are compared with computational results at several theory levels. Solvation effects are considered only by coordination of lithium with two THF molecules. Best results are obtained with the hybrid density‐functional method mPW1PW91, which gives satisfactory results over a range of almost 40 pK units, but explicit thermal corrections to 25° are required.
Intermolecular Reactions of γ‐Halocarbanions – Stepwise Analogs of 1,3‐Dipolar Cycloaddition
Authors: Barbasiewicz Michał , Mąkosza Mieczysław 
Published: October 2012

Abstractγ‐Halocarbanions, short‐lived intermediates, add to electron‐deficient double bonds of aldehydes, Michael acceptors, and imines to form anionic adducts that enter intramolecular 1,5‐substitution to form five‐membered rings of tetrahydrofurans, cyclopentanes, and pyrrolidines, respectively. Although the γ‐halocarbanions can be generated by simple deprotonation of appropriate precursors, a wealth of other methods based on Lewis acid‐catalyzed opening of cyclopropanes with formation of dipolar species utilizes a similar mechanistic scheme. In our review, we analyze kinetic relations of elementary processes in the multistep transformations, and demonstrate how structural factors influence the mechanisms and selectivity of the reaction.
Studies on AlkylNitrogen Bond Formation via Reductive Elimination from Monomeric Palladium Complexes in High Oxidation State
Authors: Iglesias Álvaro , Muñiz Kilian 
Published: October 2012

AbstractOxidation of a series of defined palladium(II) complexes bearing a bidentate ligand, and a methyl and an amidato substituent was carried out with the aim to gain a better understanding of the inherent requirements for CN bond‐formation from Pd complexes in high oxidation state. This work clarified the role of the individual nitrogen sources and has important implication for alkylnitrogen bond‐forming reactions catalyzed by Pd.
Oxidative Cleavage and Rearrangement of Aryl Epoxides Using Iodosylbenzene: on Criegee's Trail
Authors: Havare Nizam , Plattner Dietmar A. 
Published: October 2012

AbstractAryl epoxides undergo rearrangement and oxidative cleavage when reacted with in situ prepared hydroxy‐λ3‐iodane complexes. The presence of H2O plays a decisive role in steering the reaction path. A mechanistic scheme is proposed that accounts for the observed chemoselectivities.
Effects of Juvenile Hormone and Precocene on the Reproduction of Brachionus calyciflorus
Authors: Lv Linlan , Jiang Qichen , Chen1 Xuejiao , Yang Jiaxin 
Published: October 2012

AbstractWe studied the effects of juvenile hormone and precocene on reproduction of the rotifer Brachionus calyciflorus. Amictic females of B. calyciflorus that were 2‐4 hours old were exposed to different concentrations of juvenile hormone (0.004, 0.02, 0.1, 0.5, 2.5, 12.5 mg/L) and/or precocene (0.05, 0.25, 0.75, 3.75, 7.5 mg/L) for 24 h. They were then transferred to a new medium without hormone and checked every 2 h during the next 48 h, and thereafter monitored daily until the individual died. Precocene had no effects on the length of the rotifer juvenile period, hatching time of the first neonate, lifetime reproduction, or the mixis ratio. In contrast, juvenile hormone at 0.5, 2.5, and 12.5 mg/L significantly prolonged the juvenile period by 6.1, 9.2, and 8.6%, respectively. When 26‐28‐h‐old amictic females were exposed to the same concentration series of juvenile hormone or precocene, precocene at 3.75 mg/L resulted in an increase in lifetime reproduction of 30.39%. However, at 0.75 and 3.75 mg/L precocene, a significantly lower percentage of mictic females was found, whereas juvenile hormone had no effect on the lifetime reproduction or mixis ratio. The population growth test showed that juvenile hormone had significant effects on the population growth rate and mixis ratio, but no effect on resting egg production. In comparison, precocene had no effect on any of these parameters. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
In vitro chondrogenesis by BMP6 gene therapy
Authors: Kayabaşi Gonca Karagöz , Tiğli Aydin R. Seda , Gümüşderelioğlu Menemşe 
Published: October 2012

AbstractIn this study, the promotion of in vitro chondrogenesis was investigated by using chitosan scaffolds and rat bone marrow‐derived mesenchymal stem cells (rBMSCs) which are transfected by BMP6 (bone morphogenetic protein‐6) encoding gene. For this purpose, plasmid DNA (pShuttle‐rBMP6), the expression vector consisting of the coding sequence of the BMP6 was obtained, and then, it was entrapped in chitosan scaffolds to obtain a gene‐activated matrix (GAM). The chitosan scaffolds performed the controlled and sustained release of plasmid DNA, thus they continuously provided the modification of rBMSCs to induce chondrogenic differentiation. In addition, the cells were transfected by lipid‐based agent (Lipofectamine) and then, these modified cells were inoculated into the chitosan scaffolds. Furthermore, a group of chitosan scaffolds with nontransfected rBMSCs with recombinant BMP6 free in culture medium was used as control. Comparative results showed that, mitochondrial activities of modified rBMSCs by Lipofectamine and chitosan GAM were significantly higher than those of nontransfected rBMSCs. The observations from scanning electron microscopy analysis confirmed that BMP6 gene‐modified rBMSCs differentiated to the chondrogenic phenotype. Highest amount of glycosaminoglycan contents of rBMSCs on GAM concluded that BMP6 gene‐activated chitosan scaffold has a potential in the application of cartilage regeneration. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Electrical signals guided entrapment and controlled release of antibiotics on titanium surface
Authors: Shi Xiaowen , Wu Huiping , Li Yuanyuan , Wei Xiaoquan , Du Yumin 
Published: October 2012

AbstractElectrical signals are used to trigger the entrapment and release of antibiotics on the surface of titanium plate. The entrapment of antibiotics relies on the electrochemically induced pH gradient generated at the titanium surface that allows the gelation of an aminopolysaccharide chitosan and codeposition of vancomycin, a common antibiotic, within chitosan gel. The release of vancomycin is controlled by an anodic signal imposed to the titanium plate that causes a pH decrease and erosion of chitosan gel. We show that the on demand entrapment and release of vancomycin at the surface of titanium plate is fundamentally altered and controlled by voltage. We expect that this rapid, mild and facile electrochemical process for antibiotics loading and release will find applications in controlled drug release from titanium implants. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Accurate dynamical structure factors fromab initiolattice dynamics: The case of crystalline silicon
Authors: Erba Alessandro , Ferrabone Matteo , Orlando Roberto , Dovesi Roberto 
Published: October 2012

AbstractA fullyab initiotechnique is discussed for the determination of dynamical X‐ray structure factors (XSFs) of crystalline materials, which is based on a standard Debye–Waller (DW) harmonic lattice dynamical approach with all‐electron atom‐centered basis sets, periodic boundary conditions, and one‐electron Hamiltonians. This technique requires an accurate description of the lattice dynamics and the electron charge distribution of the system. The main theoretical parameters involved and final accuracy of the technique are discussed with respect to the experimental determinations of the XSFs at 298 K of crystalline silicon. An overall agreement factor of 0.47% between theab initiopredicted values and the experimental determinations is found. The best theoretical determination of the anisotropic displacement parameter, of silicon is here 60.55 × 10−4Å2, corresponding to a DW factorB= 0.4781 Å2. © 2012 Wiley Periodicals, Inc.
On the choice of a reference state for one‐step perturbation calculations between polar and nonpolar molecules in a polar environment
Authors: Lin Zhixiong , van Gunsteren Wilfred F. 
Published: October 2012

AbstractOne‐step perturbation is an efficient method to estimate free energy differences in molecular dynamics (MD) simulations, but its accuracy depends critically on the choice of an appropriate, possibly unphysical, reference state that optimizes the sampling of the physical end states. In particular, the perturbation from a polar moiety to a nonpolar one and vice versa in a polar environment such as water poses a challenge which is of importance when estimating free energy differences that involve entropy changes and the hydrophobic effect. In this work, we systematically study the performance of the one‐step perturbation method in the calculation of the free enthalpy difference between a polar water solute and a nonpolar “water” solute molecule solvated in a box of 999 polar water molecules. Both these polar and nonpolar physical reference states fail to predict the free enthalpy difference as obtained by thermodynamic integration, but the result is worse using the nonpolar physical reference state, because both a properly sized cavity and a favorable orientation of the polar solute in a polar environment are rarely, if ever, sampled in a simulation of the nonpolar solute in such an environment. Use of nonphysical soft‐core reference states helps to sample properly sized cavities, and post‐MD simulation rotational and translational sampling of the solute to be perturbed leads to much improved free enthalpy estimates from one‐step perturbation. © 2012 Wiley Periodicals, Inc.
Solving the problem of negative populations in approximate accelerated stochastic simulations using the representative reaction approach
Authors: Kadam Shantanu , Vanka Kumar 
Published: October 2012

AbstractMethods based on the stochastic formulation of chemical kinetics have the potential to accurately reproduce the dynamical behavior of various biochemical systems of interest. However, the computational expense makes them impractical for the study of real systems. Attempts to render these methods practical have led to the development of accelerated methods, where the reaction numbers are modeled by Poisson random numbers. However, for certain systems, such methods give rise to physically unrealistic negative numbers for species populations. The methods which make use of binomial variables, in place of Poisson random numbers, have since become popular, and have been partially successful in addressing this problem. In this manuscript, the development of two new computational methods, based on the representative reaction approach (RRA), has been discussed. The new methods endeavor to solve the problem of negative numbers, by making use of tools like the stochastic simulation algorithm and the binomial method, in conjunction with the RRA. It is found that these newly developed methods perform better than other binomial methods used for stochastic simulations, in resolving the problem of negative populations. © 2012 Wiley Periodicals, Inc.
Repeated fed‐batch production of xylitol by Candida magnoliaeTISTR 5663
Authors: Sirisansaneeyakul Sarote , Wannawilai Siwaporn , Chisti Yusuf 
Published: October 2012

AbstractBackgroundXylitol is an important commercial sweetener that can be produced by fermentation. Previous studies of xylitol production have not been able to combine a high final product concentration, and a high average productivity and yield, in a single process.ResultsHigh‐cell density cultures of the yeast Candida magnoliae TISTR 5663 were used to produce xylitol by repeated fed‐batch fermentations under oxygen limiting conditions involving feeding of xylose and nitrogen. Xylitol yields of 0.727, 0.719 and 0.720 g g−1 were obtained at average biomass concentrations of 21, 48, and 50 g L−1, respectively, using an initial xylose concentration of ∼60 g L−1 under controlled conditions (agitation rate 300 rpm, aeration rate 1.0 vvm, pH 7.0, 30°C). For a total duration of 750 h of a repeated fed‐batch fermentation, an average xylitol productivity of 1.149 g L−1 h−1 was attained within the fed‐batch periods. The final xylitol concentration was in the range 235–284 g L−1 depending on the stage of feeding.ConclusionThe fed‐batch xylitol production developed in this work combined high final product concentration, xylitol productivity and yield in a single process.© 2012 Society of Chemical Industry
Rhizodeposition: Its contribution to microbial growth and carbon and nitrogen turnover within the rhizosphere
Authors: Schenck zu Schweinsberg‐Mickan Mario , Jörgensen Rainer Georg , Müller Torsten 
Published: October 2012

AbstractA greenhouse rhizobox experiment was carried out to investigate the fate and turnover of 13C‐ and 15N‐labeled rhizodeposits within a rhizosphere gradient from 0–8 mm distance to the roots of wheat. Rhizosphere soil layers from 0–1, 1–2, 2–3, 3–4, 4–6, and 6–8 mm distance to separated roots were investigated in an incubation experiment (42 d, 15°C) for changes in total C and N and that derived from rhizodeposition in total soil, in soil microbial biomass, and in the 0.05 M K2SO4–extractable soil fraction. CO2‐C respiration in total and that derived from rhizodeposition were measured from the incubated rhizosphere soil samples. Rhizodeposition C was detected in rhizosphere soil up to 4–6 mm distance from the separated roots. Rhizodeposition N was only detected in the rhizosphere soils up to 3–4 mm distance from the roots. Microbial biomass C and N was increased with increasing proximity to the separated roots. Beside 13C and 15N derived from rhizodeposits, unlabeled soil C and N (native SOM) were incorporated into the growing microbial biomass towards the roots, indicating a distinct acceleration of soil organic matter (SOM) decomposition and N immobilization into the growing microbial biomass, even under the competition of plant growth. During the soil incubation, microbial biomass C and N decreased in all samples. Any decrease in microbial biomass C and N in the incubated rhizosphere soil layers is attributed mainly to a decrease of unlabeled (native) C and N, whereas the main portion of previously incorporated rhizodeposition C and N during the plant growth period remained immobilized in the microbial biomass during the incubation. Mineralization of native SOM C and N was enhanced within the entire investigated rhizosphere gradient. The results indicate complex interactions between substrate input derived from rhizodeposition, microbial growth, and accelerated C and N turnover, including the decomposition of native SOM (i.e., rhizosphere priming effects) at a high spatial resolution from the roots.
On the existence of low‐diaphony sequences made of digital sequences and lattice point sets
Authors: Kritzer Peter , Pillichshammer Friedrich 
Published: October 2012

AbstractIn this paper, we discuss hybrid point sets built from two of the most prominent classes of sequences used in quasi‐Monte Carlo methods. We derive an existence result on point sets with low diaphony, where the components of the points involved stem from a digital (t,s)‐sequence on the one hand, and from a lattice point set on the other. Moreover, we outline how the hybrid diaphony of the point sets considered in this paper relates to the worst‐case integration error in suitable function spaces.
3D Photofixation Lithography in Diels–Alder Networks
Authors: Adzima Brian J. , Kloxin Christopher J. , DeForest Cole A. , Anseth Kristi S. , Bowman Christopher N. 
Published: October 2012

Abstract3D structures are written and developed in a crosslinked polymer initially formed by a Diels–Alder reaction. Unlike conventional liquid resists, small features cannot sediment, as the reversible crosslinks function as a support, and the modulus of the material is in the MPa range at room temperature. The support structure, however, can be easily removed by heating the material, and depolymerizing the polymer into a mixture of low‐viscosity monomers. Complex shapes are written into the polymer network using two‐photon techniques to spatially control the photoinitiation and subsequent thiol–ene reaction to selectively convert the Diels–Alder adducts into irreversible crosslinks.
Coping strategies of Spanish pregnant women and their impact on anxiety and depression
Authors: Peñacoba‐Puente Cecilia , Carmona‐Monge Francisco Javier , Marín‐Morales Dolores , Naber Katharina 
Published: October 2012

AbstractThe aims of this study were to analyze the coping strategies used by women in the first trimester of low‐risk pregnancies, their relationships to sociodemographic and pregnancy variables, and their ability to predict anxiety and depression in the third trimester. Participants in the first trimester were 285 Spanish pregnant women, of whom 122 were followed into the third trimester. The use of problem‐focused coping was stable, whereas variations occurred in emotion‐focused coping. Age, educational level, employment, planned pregnancy, previous childbirth, and previous miscarriage were associated with adaptive coping. Coping strategies predicting anxiety and depressive symptoms were overt emotional expression and social support seeking. Coping through religion predicted anxiety. Coping is a complex process influenced by sociodemographic and obstetric factors that can contribute to the onset of psychological symptoms. © 2012 Wiley Periodicals, Inc. Res Nurs Health 36:54–64, 2013
Mit neuer Software zum virtuellen Warenlager
Authors: Kreutzer Lutz , Ulrich Markus 
Published: October 2012

AbstractIn der industriellen Bildverarbeitung zählt HALCON von MVTec zu den weltweit führenden Softwarebibliotheken. Die neue Version 11 der Software bietet Innovationen, die dem gesamten Machine Vision Markt einen neuen Schub geben werden.
Zeilenkameras für die industrielle Bildverarbeitung
Authors: Gips Peter , Oechsner Ulrich 
Published: October 2012

AbstractZeilenkameras sind Halbleiterkameras mit nur einer lichtempfindlichen Zeile. Sie finden Ihre Verwendung vor allem im industriellen Umfeld. Eingesetzt werden Zeilenkameras entweder zur Ermittlung eindimensionaler Messgrößen, wie z.B. der Breite eines Spaltes, oder in Verbindung mit einer scannenden Bewegung zur Aufnahme eines zweidimensionalen Bildes, wie z. B. bei einem Faxgerät oder Kopierer. Vorzüge der Zeilenkameras sind hohe optische Auflösung, hohe Geschwindigkeit, freie Dimensionierung der Bildhöhe und Synchronisierbarkeit jeder einzelnen Zeile. Sie eröffnen vielfältige Einsatzmöglichkeiten in der industriellen Bildverarbeitung. Bei Bahnmaterialien, Förderbändern oder ähnlichem, bieten Zeilenkameras zudem die Möglichkeit kontinuierlicher Endlosaufnahmen. Zur Rechneranbindung stehen dem Anwender moderne digitale Schnittstellen wie Gigabit Ethernet, USB 2.0 (demnächst 3.0), CameraLink und LVDS zur Auswahl.
Prenatal diagnosis of congenital heart disease: impact of mode of delivery on neonatal outcome
Authors: Trento Luca U. , Pruetz Jay D. , Chang Ruey K. , Detterich Jon , Sklansky Mark S. 
Published: October 2012

ABSTRACTObjectiveWe sought to evaluate the impact of mode of delivery (MOD) on early outcome for neonates diagnosed prenatally with major forms of congenital heart disease (CHD).MethodsWe retrospectively studied infants admitted, over a 2‐year period, to a single institution for cardiac intervention. Infants were grouped on the basis of timing of diagnosis (prenatal/postnatal) and MOD – planned (induced labor or planned cesarean delivery) versus spontaneous labor. Multivariate logistic regression was used to evaluate independent predictors for MOD and early outcomes.ResultsOf 329 patients, 45% received a prenatal diagnosis of CHD. A prenatal diagnosis of CHD increased the likelihood for planned delivery [odds ratio (OR) 2.6, 95% confidence interval (CI) 1.6 to 4.5, p < 0.001]. Newborns prenatally diagnosed with CHD were more likely to have been delivered between 8 am and 6 pm, Monday through Friday (OR 2.3, 95% CI 1.1 to 4.8, p = 0.019). However, MOD had no statistical impact on Apgar score, duration of pre‐operative intubation, and survival to surgery or to discharge. The Risk Adjustment for Congenital Heart Surgery 1 surgical mortality score was the only independent predictor of hospital mortality.ConclusionsIn our experience, although a prenatal diagnosis of CHD decreased the likelihood of spontaneous labor, MOD had no demonstrable impact on neonatal outcome. © 2012 John Wiley & Sons, Ltd.
Problem‐focussed interactive telephone therapy for cancer patients: a phase II feasibility trial
Authors: Watson M. , White C. , Davolls S. , Mohammed A. , Lynch A. , Mohammed K. 
Published: October 2012

AbstractObjectiveThe study aimed to evaluate Problem‐Focussed Interactive Telephone Therapy, an individual psychological therapy based on cognitive‐behavioural therapy adapted for telephone delivery to cancer patients with high psychological needs.MethodsA non‐randomised, within‐group prospective design was used. Outcome measures pre‐therapy and post‐therapy included were as follows: Hospital Anxiety and Depression Scale, Mental Adjustment to Cancer Scale: helpless/hopeless sub‐scale only, Checklist of Cancer Concerns, Cancer Coping Questionnaire and EQ‐5D quality of life. A study‐specific Service Evaluation Questionnaire was included. Eligible patients were either (i) offered out‐patient screening for anxiety/depression/helplessness (n = 649) or (ii) referred for psychological care by oncology clinicians (n = 160).ResultsThirty two percent (36/114) of screen‐identified cases and 22% (35/160) of referred patients participated, and 42 were available for analysis. There were significant post‐therapy improvements in Hospital Anxiety and Depression Scale anxiety (p = 0.002) and depression (p = 0.003), Mental Adjustment to Cancer Scale helpless/hopeless (p = 0.036), cancer concerns (p = 0.005) and overall quality of life (p = 0.048). Overall, 81% (34/42) of participants were defined as clinical cases at baseline and 32% were no longer cases post‐therapy. There were significant improvements in coping consistent with the therapy method.ConclusionsA minority of symptomatic patients opt for telephone psychological therapy; however, where they do, there are significant improvements indicating that telephone‐delivered therapy is feasible in patients with high needs. Findings are discussed in relation to current issues on the implementation of distress screening and psychological therapy provision within clinical settings. Copyright © 2012 John Wiley & Sons, Ltd.
Fluenz: a new influenza vaccine administered intranasally
Authors: Chaplin Steve , Thors Valtyr , Finn Adam 
Published: October 2012

AbstractFluenz is a live attenuated influenza vaccine given intranasally. In our New products review, Steve Chaplin presents the clinical data relating to its efficacy and adverse events, and Dr Thors and Professor Finn discuss its place in the new NHS influenza vaccination programme in children.