bluuebunny/crossref_metadata_2025_split huggingface dataset:
Primary Amine Attached to an N‐(Carboxyalkyl)imidazolium Cation: A Recyclable Organocatalyst for the Asymmetric Michael Reaction
Authors: Kucherenko Alexandr S. , Lisnyak Vladislav G. , Chizhov Alexandr O. , Zlotin Sergei G. 
Published: May 2014

AbstractA (1S,2S)‐1,2‐diphenylethane‐1,2‐diamine derivative modified with an N‐(4‐carboxybutyl)imidazolium cation and PF6– anion has been developed and applied as a recyclable organocatalyst of the asymmetric 1,4‐conjugate addition of 4‐hydroxy‐2H‐chromen‐2‐one to 1‐substituted buten‐3‐ones or cyclohexen‐3‐one to afford corresponding Michael adducts in high yields (up to 97 %) and enantioselectivities (up to 90 % ee). The most active (S) enantiomer of the clinically useful anticoagulant warfarin was prepared in this way. The catalyst exhibited better recyclability than its known analog, which does not contain a carboxy group: it could be recycled 5 times in the reaction without a significant decrease in product yield or ee values. Gradual deactivation of the catalyst was caused by leaching during workup rather than by off‐cycle reactions between the catalyst and reagents.
Task structure, need for structure, and creativity
Authors: Rietzschel Eric F. , Slijkhuis J. Marjette , Van Yperen Nico W. 
Published: May 2014

AbstractAlthough creativity is often seen as requiring spontaneity and flexibility, recent work suggests that there is creative potential in a structured and systematic approach as well. In a series of four experiments, we show that when Personal Need for Structure (PNS) is high, either chronic (Study 1) or situationally induced (Study 2), creative performance benefits from high task structure. Further, in line with earlier work on cognitive fixation effects, we show that when high task structure contains an example of noncreative task execution, creative performance is impaired, regardless of individuals' PNS. Nevertheless, participants high in PNS react relatively favorably to high task structure (Study 3) and are more likely to adopt a structured task approach when given the choice (Study 4). In sum, our results show that task structure can both stimulate and inhibit creative performance, particularly for people high in need for structure. Copyright © 2014 John Wiley & Sons, Ltd.
When in Rome… Identification and acculturation strategies among minority members moderate the dehumanisation of the majority outgroup
Authors: Miranda Mariana , Gouveia‐Pereira Maria , Vaes Jeroen 
Published: May 2014

AbstractThe study of humanness as a dimension of social judgment has received extensive attention over the past decade. Although the common reported finding is that people attribute more human characteristics to their ingroup than to the outgroup, similar tendencies are expected to be tempered for minority groups when judging the host society. In Study 1, carried out with Gypsy minority members, we tested the hypothesis that those group members who adopt an assimilative strategy identifying more with the host compared with the heritage culture will display the lowest levels of dehumanisation. In Studies 2 and 3, conducted with immigrants in Italy and in Portugal, respectively, the hypothesis was extended from an identification conceptualisation to an acculturation one. Despite significant variability in intergroup settings and measures, results confirmed our hypothesis that immigrants who choose to assimilate with the host culture dehumanise the outgroup less compared with those who adopt any of the other acculturation strategies. Implications for the ethnocentric nature of dehumanisation biases and for intergroup relations in general are discussed. Copyright © 2014 John Wiley & Sons, Ltd.
Analytical Expressions of the Concentrations of Substrate, Biomass, and Ethanol for Solid‐State Fermentation in Biofuel Production
Authors: Kirthiga Ondivillu Mothilal , Rajendran Lakshmanan 
Published: May 2014

AbstractMathematical and kinetic models are discussed for anaerobic solid‐state fermentation (SSF) in rotating‐drum bioreactors (RDBs). In this study, a simple approximate analytical expression pertaining to the concentration of substrate, biomass, and ethanol is derived in terms of all parameters. These analytical results were found to be in good agreement with numerical solutions (MATLAB/SCILAB) and experimental results.
Gas Analysis of Carbon Oxidation in a Coin‐Type Direct Carbon Fuel Cell
Authors: Lee C. G. , Pak J. 
Published: May 2014

AbstractCarbon oxidation behaviors were illuminated in terms of gas composition in a coin‐type direct carbon fuel cell. The main gas species in the anode chamber at 850 °C was mostly carbon monoxide, which was generated from the chemical reaction of carbon and molten carbonates. The concentration of CO was reduced as time passed because the reactivity of carbonates was weakened. The open circuit voltage was directly dependent on the CO concentration. The gases in the anode chamber had a vertical concentration distribution; the highest CO and the lowest CO2 concentrations were observed near the electrode. However, the voltage in the polarization state was less dependent on the gas composition. A polarization state of 150 mA cm–2 allowed the oxidation of CO, resulting in an increased CO2 concentration near the electrode. The enlarged CO2 partial pressure facilitated CO generation through the recombination of carbonate ions (CO32–). Decreasing the temperature from 850 to 750 °C reduced the level of carbon monoxide at the anode. The presence of CO as a main component in the anode concludes that the oxidation of solid carbon takes place through the gasification of carbon to CO, then electrochemically to CO2.
Design and Optimization of an Innovative Solid Oxide Fuel Cell–Gas Turbine Hybrid Cycle for Small Scale Distributed Generation
Authors: Facchinetti E. , Favrat D. , Marechal F. 
Published: May 2014

AbstractDistributed power generation and cogeneration is an attractive way toward a more rational conversion of fuel and biofuel. The fuel cell‐gas turbine hybrid cycles are emerging as the most promising candidates to achieve distributed generation with comparable or higher efficiency than large‐scale power plants. The present contribution is devoted to the design and optimization of an innovative solid oxide fuel cell–gas turbine hybrid cycle for distributed generation at small power scale, typical of residential building applications. A 5 kW planar SOFC module, operating at atmospheric pressure, is integrated with a micro gas turbine unit, including two radial turbines and one radial compressor, based on an inverted Brayton cycle. A thermodynamic optimization approach, coupled with system energy integration, is applied to evaluate several design options. The optimization results indicate the existence of optimal designs achieving exergy efficiency higher than 65%. Sensitivity analyses on the more influential parameters are carried out. The heat exchanger network design is performed for an optimal configuration and a complete system layout is proposed. An example of hybrid system integration in a common residential building is discussed.
Planar High Temperature Heat Pipes for SOFC/SOEC Stack Applications
Authors: Dillig M. , Leimert J. , Karl J. 
Published: May 2014

AbstractTargeting transient operation of high temperature solid oxide cell (SOC) systems this paper proposes an enhanced heat management mechanism using planar high temperature heat pipes that can be integrated into the SOC‐stack structure. Flat heat pipes with thicknesses down to 4 mm filled with liquid alkali metals for almost isothermal 2D heat spreading, even for intense heat transfer rates, are demonstrated. A new pathway towards a temperature gradient shrinking in SOC‐stacks without using large amounts of additional air‐cooling is shown. The paper will present latest development results on design concepts, size reduced fabrication and filling procedure. An experimental study demonstrates the heat spreading capabilities and power limitations of planar heat spreaders for high temperature applications as in SOEC/SOFC stacks.
Salvage surgery for recurrent carcinoma of the cervical esophagus postesophagectomy
Authors: Chow Velda L. Y. , Chan Jimmy Y. W. , Wei William I. 
Published: May 2014

AbstractBackgroundManagement of cervical esophageal tumor postesophagectomy is mainly palliative because of inadequate exposure of tumor in the cervicothoracic region. In this study, we propose a means of cure for these patients.MethodsBetween January 2003 and June 2013, 6 patients underwent curative pharyngolaryngectomy and completion cervical esophagectomy via manubrial resection. Operative outcomes were analyzed and compared with a historical cohort who received palliative therapy.ResultsOne patient required prolonged hospital stay for pneumonia, resulting in a median hospital stay of 30 days (range, 21–55 days). All patients resumed oral feeding at a mean of 15.2 days (range, 14–19 days). Tracheostoma stenosis was noted in 2 patients. One patient developed nodal recurrence, another with distant metastasis, resulting in a median disease‐free survival of 13 months (range, 4–20 months). Median overall survival was significantly longer than the cohort group (19.0 vs 3.0 months; p = .013).ConclusionSalvage surgery in patients with carcinoma of the cervical esophagus postesophagectomy is feasible with significantly prolonged survival. © 2014 Wiley Periodicals, Inc. Head Neck 37: 1170–1175, 2015
Hippocampal slow EEG frequencies during NREM sleep are involved in spatial memory consolidation in humans
Authors: Moroni Fabio , Nobili Lino , Iaria Giuseppe , Sartori Ivana , Marzano Cristina , Tempesta Daniela , Proserpio Paola , Lo Russo Giorgio , Gozzo Francesca , Cipolli Carlo , De Gennaro Luigi , Ferrara Michele 
Published: May 2014

ABSTRACTThe hypothesis that sleep is instrumental in the process of memory consolidation is currently largely accepted. Hippocampal formation is involved in the acquisition of declarative memories and particularly of spatial memories. Nevertheless, although largely investigated in rodents, the relations between spatial memory and hippocampal EEG activity have been scarcely studied in humans. Aimed to evaluate the effects of spatial learning on human hippocampal sleep EEG activity, we recorded hippocampal Stereo‐EEG (SEEG) in a group of refractory epilepsy patients undergoing presurgical clinical evaluation, after a training on a spatial navigation task. We observed that hippocampal high‐delta (2–4 Hz range) activity increases during the first NREM episode after learning compared to the baseline night. Moreover, the amount of hippocampal NREM high‐delta power was correlated with task performance at retest. The effect involved only the hippocampal EEG frequencies inasmuch no differences were observed at the neocortical electrodes and in the traditional polysomnographic measures. The present findings support the crucial role of hippocampal slow EEG frequencies during sleep in the memory consolidation processes. More generally, together with previous results, they suggest that slow frequency rhythms are a fundamental characteristic of human hippocampal EEG during both sleep and wakefulness, and are related to the consolidation of different types of memories. © 2014 Wiley Periodicals, Inc.
Folding of Right‐ and Left‐Handed Three‐Helix Proteins
Authors: Galzitskaya Oxana V. , Pereyaslavets Leonid B. , Glyakina Anna V. 
Published: May 2014

AbstractWe are the first to investigate the relationship between protein handedness and the rate of protein folding. Our findings demonstrate that small three‐helix, left‐handed proteins are less densely packed and should result in faster folding than that of right‐handed, three‐helix proteins. At the same time, right‐handed, three‐helix proteins have higher mechanical stability than the left‐handed proteins. Moreover, from our analysis we have revealed that bacterial three‐helix proteins have some advantages in packing over eukaryotic right‐handed, three‐helix proteins, which should result in faster folding.
Silica Colloidal Membranes with Enantioselective Permeability
Authors: Ignacio‐de Leon Patricia A. , Abelow Alexis E. , Cichelli Julie A. , Zhukov Arkady , Stoikov Ivan I. , Zharov Ilya 
Published: May 2014

AbstractRobust mesoporous membranes composed of silica spheres were surface‐modified with chiral selector moieties, including small molecules, macrocycles, and polymers. Diffusion rates of enantiomers of a chiral dye through the resulting asymmetrically modified colloidal membranes were measured and the corresponding permselectivities were calculated. The membranes showed enantioselectivities in the range of 1.2–1.8, which were not significantly affected by the structure of the surface‐immobilized chiral electors. This selectivity is on par with most reported polymer‐based solid membranes and bulk liquid membranes. The enantioselectivity results from the surface‐facilitated mechanism of transport of enantiomers through the mesopores.
Stem cell adhesion and proliferation on hydrolyzed poly(butylene succinate)/β‐tricalcium phosphate composites
Authors: Patntirapong Somying , Singhatanadgit Weerachai , Meesap Preeyapan , Theerathanagorn Tharinee , Toso Montree , Janvikul Wanida 
Published: May 2014

AbstractAlthough poly(butylene succinate)/β‐tricalcium phosphate (PBSu/TCP) composites are biocompatible and allow the growth and osteogenic differentiation of stem cells, cell attachment and adhesion to the PBSu‐based substrates is often limited. To enhance cell adhesion and proliferation, we used a sodium hydroxide (NaOH) hydrolysis technique to generate a different degree of roughness on PBSu/TCP substrates with different PBSu:TCP ratios. The results showed that NaOH hydrolysis increased surface roughness of PBSu/TCP substrates in a concentration‐dependent manner. Substrates with higher ratios of TCP:PBSu provided more porous topography after NaOH hydrolysis, with a substrate containing 40 wt % TCP (PBSu/TCP‐6040) hydrolyzed with 1.5MNaOH (HPBSu/TCP‐6040‐1.5) showing the highest degree of roughness. As with the roughness, PBSu/TCP surface hydrophilicity was positively affected by the increasing NaOH concentration and TCP incorporation. Stem cells adhered best on HPBSu/TCP‐6040‐1.5 with three‐dimensionally elongated cell extensions. Moreover, the HPBSu/TCP‐6040‐1.5 substrate most significantly facilitated stem cell actin cytoskeleton reorganization and vinculin‐positive focal adhesion formation when compared with the other substrates tested. HPBSu/TCP‐6040‐1.5 also demonstrated the greatest increase in cell proliferation when compared with the other substrates studied. In conclusion, the results have shown that among various substrates tested, HPBSu/TCP‐6040‐1.5 provided the best support for stem cell adhesion and proliferation, suggesting its potential use in bone engineering. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 658–670, 2015.
Structure and function of placental exchange surfaces in goodeid fishes (Teleostei: Atheriniformes)
Authors: Schindler Joachim F. 
Published: May 2014

ABSTRACTThe species of the family Goodeidae have evolved reproductive strategies involving intraovarian gestation, early evacuation of nearly yolk‐exhausted embryos from the ovigerous tissue into the ovarian cavity, placental matrotrophy during intraluminal gestation, and the birth of highly developed fry. The inner ovarian lining becomes hypervascularized during gestational periods and functions as the maternal component of the placental association. Embryotrophic liquid is secreted by the inner ovarian epithelium into the ovarian cavity. Comparative electrophoretic analyses of embryotrophe and maternal blood serum provide evidence for the transfer of maternal serum proteins into the embryotrophe. Trophotaeniae, proctodaeal processes of the embryos, provide a surface for nutrient absorption. Endocytic activity was demonstrated by ingestion of unspecific tracer proteins in various species. Moreover, the trophotaenial absorptive cells (TACs) in Ameca splendens ingest various proteins or random copolymers conjugated to colloidal gold as well as radioiodinated proteins in a way that satisfies the criteria of receptor‐mediated endocytosis. Several aminopeptidases (APs) on the surface of TACs were identified as protein binding sites as evidenced by inhibition of binding and uptake of marker proteins in the presence of AP substrates or AP inhibitors. Morphological adaptations of the embryonic circulatory system pertaining to nutrient and gas exchange were characterized. The embryonic epidermis comprises two layers of squamous cells closely underlain by a dense capillary net. Efficient gas exchange is facilitated by a thin embryotrophe‐blood barrier of both the embryonic skin and the intraovarian lining. J. Morphol. 276:991–1003, 2015. © 2014 Wiley Periodicals, Inc.
Whole‐genome based validation of the adaptive properties of Indian origin probiotic Lactobacillus helveticusMTCC 5463
Authors: Senan Suja , Prajapati Jashbhai B , Joshi Chaitanya G 
Published: May 2014

AbstractBACKGROUNDThe aim of the study was to mine the Lactobacillus helveticus MTCC 5463 genome for genetic determinants to validate its ability to adapt to gut transit stresses and translate functionality to the host.RESULTSIn silico analysis of the 1 911 350 bp single chromosome of the strain predicted that it had excellent adaptive features like the multisubunit F0F1 ATPase, conjugated bile salt hyrolase, chaperones like hsp33, HtrA, GroEL, GroES, dnaK, grpE, starvation‐inducible proteins and heavy‐metal transporting ATPases. The genome revealed genes for adhesion and aggregation including exopolysaccharides, capsular polysaccharides sortase, elongation factor Tu, aggregation promoting proteins, fibronectin‐binding proteins, S‐layer and mucus‐binding proteins. We could identify genes conferring physiological benefits like immunostimulation, cholesterol reduction, antibacterial and folate production. Thus, through trait and gene matching, the study established that the strain possessed the genetic arsenal required to adapt to the gut milieu. The predictions of functional genes further validate the experimental evidences of adaptation and probiosis.CONCLUSIONThis study provides insight into the feasibility of applying probiogenomics to identify genes that could function as pre‐selection criteria for identification of potential probiotic strains. © 2014 Society of Chemical Industry
Synthesis, Cellular Uptake, and Biodistribution of Whey‐Rich Nanoparticles
Authors: Zhen Xu , Wang Xin , Yang Chenchen , Liu Qin , Wu Wei , Liu Baorui , Jiang Xiqun 
Published: May 2014

AbstractWhey‐poly(acrylic acid) (whey‐PAA) nanoparticles are prepared by polymerizing acrylic acid (AA) monomer in the presence of whey protein in a complete aqueous medium. The properties, drug loading, and release as well as in vitro cytotoxicity of whey‐PAA nanoparticles are examined. The cellular uptakes and penetration of nanoparticle in the SH‐SY5Y monolayer cells and multicellular tumor spheroids are observed. The in vivo distribution of the nanoparticles in tumor‐bearing mice is evaluated. Confocal laser scanning microscopy and co‐localization images show that the nanoparticles are well internalized by the cells through the endocytosis mechanism. Drug‐loaded whey‐PAA nanoparticles can penetrate multicellular tumor spheroids more deeply. In vivo near‐infrared fluorescence imaging examination and in vivo DOX distribution show that the drug‐loaded whey‐PAA nanoparticles can well accumulated in the tumor site. Thus, these whey‐rich nanoparticles seem to be very promising drug carriers for drug delivery.
Calculation of effective Young's modulus distribution from electron backscatter diffraction results for stochastic analyses in aerospace applications
Authors: Dresbach C. , Dressler U. , Gussone J. , Reh S. 
Published: May 2014

In reliability analyses of safety‐relevant components it is necessary to consider the variations in load, geometry and material properties. The scatter in load, geometry and global material properties is nowadays addressed in some stochastic analyses [, ], whereas the scatter in local material properties is not adequately regarded due to difficulties in determining meaningful and stochastically relevant local material properties. In this paper a method for estimating the local distribution of the effective elastic behavior, belonging to a defined component direction, is presented. First, electron backscatter diffraction (EBSD) analyses of relevant cross sections were performed. Second, the effective elastic behavior perpendicular to the cross section was calculated for each scan point from the determined Euler angles. By using direct tensor rotation and generalized Hooke's law, the method can be applied to all kind of crystal structures if the elastic constants of the single crystal material are known.The experimental procedure, the mathematical background und the numerical realization are described in detail. Two examples of applying the procedure to materials for aerospace components as well as a stochastic finite element simulation considering the determined scatter of the elastic properties are shown.
Laser drilling of hollow sphere structures
Authors: Riegel H. , Merkel M. , Öchsner A. 
Published: May 2014

A special composite and cellular material – the metallic hollow sphere structure (MHSS) – represents an advanced material. The core element of the structure is a hollow sphere with a wall out of porous steel. This shell allows a high geometric reproducibility. It is an interesting base material for lightweight design. However, processing technologies for further manufacturing of metallic hollow sphere structure are necessary. Laser beam drilling is a highly efficient technique with heat input concentrated locally at the structure. Laser drilling is applied to metallic hollow sphere structures. The influence of different geometries and joining technologies of the spheres on the drilling behaviour is investigated.Percussion drilling is used to form holes with a CO2‐laser into the metallic hollow sphere structure. The investigated mean laser power is 400 W. Two different focal lenses with focal lengths of 5″ and 7.5″ allow investigations with different focal diameters and Rayleigh lengths. Diameter and roundness of the laser drilled holes are measured in five layers of different drill depths z. The maximum drilled depth is about 40 mm with a 5″ lense and about 50 mm with the f = 7.5″ lens. The relative roundness is determined and decreases with increasing drill depth. The diameter d(z) as a function of the drill depth follows the shape of an isophote, a line of constant intensity inside the laser beam. The brazed hollow sphere structures have considerably less drill depth than the sintered.