bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Model for High‐Temperature PEM Fuel Cell: The Role of Transport in the Cathode Catalyst Layer
Authors: Shamardina O. , Kulikovsky A. A. , Chertovich A. V. , Khokhlov A. R. 
Published: June 2012

AbstractWe report a model for HT‐PEMFC with the detailed description of transport processes in the cathode catalyst layer (CCL). The model is compared to our previous model, which assumed ideal oxygen and proton transport in the CCL. Calculations show that close to the oxygen channel inlet, the CCL works in the regime limited by poor proton transport, while close to the outlet, the CCL operation is determined by poor oxygen transport. The model is validated by fitting the experimental polarization curve; the CCL transport and kinetic parameters resulting from fitting are discussed.
Three Dimensional Model of a High Temperature PEMFC. Study of the Flow Field Effect on Performance
Authors: Sousa T. , Mamlouk M. , Scott K. , Rangel C. M. 
Published: June 2012

AbstractA three‐dimensional isothermal model of a high temperature polymer membrane fuel cell equipped with polybenzimidazole membrane is described. All major transport phenomena were taken into account except the species crossover through the membrane. The cathode catalyst layer was treated as spherical catalyst agglomerates with porous inter‐agglomerate spaces. The inter‐agglomerate spaces were filled with a mixture of electrolyte (hot phosphoric acid) and polytetrafluoroethylene (PTFE). This approach proved to be an essential requirement for accurate simulation. In this particular paper, the influence of different flow field designs and dimensions on performance was intensely study. Traditional configurations were tested (straight, serpentine, pin‐in, and interdigitated), and new designs were proposed. With these new designs, we tried to maximize performance by providing homogeneous reactants distribution over the active area keeping low‐pressure drop and relatively high velocity. The dimension and position of the inlet and outlet manifolds were also analyzed. From the obtained results a massive influence of the manifolds position and dimension on performance was observed. This fact can provide important guidelines for future bipolar plates optimization.
Immobilization of the Laccases from Trametes versicolor and Streptomyces coelicolor on Single‐wall Carbon Nanotube Electrodes: A Molecular Dynamics Study
Authors: Trohalaki S. , Pachter R. , Luckarift H. R. , Johnson G. R. 
Published: June 2012

AbstractIn this work, we investigate the immobilization of laccases from Trametes versicolor (TvL) and the small laccase (SLAC) from Streptomyces coelicolor on single‐wall carbon nanotube (SWCNT) surfaces. SLAC may potentially offer improved adsorption on the electrode, thus improving bioelectrocatalytic activity via direct electron transfer (DET). Laccase immobilization on SWCNTs is achieved non‐covalently with a molecular tether (1‐pyrene butanoic acid, succinimidyl ester) that forms an amide bond with an amine group on the laccase surface while the pyrene coordinates to the SWCNT by π–π stacking. In our approach, density functional theory calculations were first used to model the interaction energies between SWCNTs and pyrene to validate an empirical force field, thereafter applied in molecular dynamics (MD) simulations. In the simulated models, the SWCNT was placed near the region of the (type 1) Cu(T1) atom in the laccases, and in proximity to other regions where adsorption seems likely. Calculated interaction energies between the SWCNTs and laccases and distances between the SWCNT surface and the Cu(T1) atom have shown that SWCNTs adsorb more strongly to SLAC than to TvL, and that the separation between the SWCNTs and Cu(T1) atoms is smaller for SLAC than for TvL, having implications for improved DET.
Rapid In Situ Synthesis of Spherical Microflower Pt/C Catalyst Via Spray‐drying for High Performance Fuel Cell Application
Authors: Balgis R. , Anilkumar G. M. , Sago S. , Ogi T. , Okuyama K. 
Published: June 2012

AbstractA facile route for the rapid in situ synthesis of platinum nanoparticles on spherical microflower carbon has been developed. An aqueous precursor slurry containing carbon black, polystyrene latex (PSL), polyvinyl alcohol, and platinum salt was spray‐dried, followed by calcination to simultaneously reduce platinum salt and to decompose PSL particles. Prepared Pt/C catalyst showed high‐performance electrocatalytic activity with excellent durability. The mass activity and specific activity values were 132.26 mA mg–1 Pt and 207.62 μA cm–2 Pt, respectively. This work presents a future direction for the production of high‐performance Pt/C catalyst in an industrial scale.
ApoE4 is not associated with depression when mild cognitive impairment is considered
Authors: Nose Mayumi , Kodama Chiine , Ikejima Chiaki , Mizukami Katsuyoshi , Matsuzaki Asaki , Tanaka Shiro , Yoshimura Atsuko , Yasuno Fumihiko , Asada Takashi 
Published: June 2012

ObjectiveThe aim of the study was to examine the relationship between apolipoprotein E4 allele (ApoE4) and depression among an older Japanese population. Mild cognitive impairment (MCI) was taken into consideration.MethodsThis is a community‐based cross‐sectional study. We assessed the mood and cognitive function of Japanese community‐dwelling individuals aged 65 years or older. In the first phase of the study, we evaluated the mood and cognitive function. In the second phase, face‐to‐face structured interviews were conducted. Individuals with dementia and other mental diseases were excluded on the basis of a consensus meeting of psychiatrists and neuropsychologists; 738 subjects with full data were included in the analyses. We subdivided depression into major depressive episode (MDE) and depressive symptoms cases (DSCs). DSC was defined as a score of 6 or more on the Geriatric Depression Scale but not having a diagnosis of MDE. The relationship between depression (MDE and DSC) and ApoE4 was examined by multivariate logistic regression.ResultsThe adjusted odds ratio (OR) of ApoE4 on DSC was not significant (OR = 0.82, 95%CI = 0.48–1.39, p < 0.46). Sex (OR = 2.53, 95%CI = 1.33–4.79, p < 0.01), MCI (1.95, 1.21–3.14, p < 0.01), years of education (0.87, 0.79–0.95, p < 0.01), and Nishimura's activities of daily living scores (0.75, 0.63–0.89, p < 0.01) significantly correlated with prevalence of DSC. There were no significant risk factors for MDE.ConclusionApolipoprotein E4 allele contributed to neither DSC nor MDE. The association of MCI with ApoE4 and DSC suggested that MCI is a confounder for the association between ApoE4 and DSC. Copyright © 2012 John Wiley & Sons, Ltd.
Management of apathy in nursing homes using a teaching program for care staff: the STIM‐EHPAD study
Authors: Leone Elsa , Deudon Audrey , Bauchet Murielle , Laye Mathilde , Bordone Nathalie , Lee Ji‐Hyun , Piano Julie , Friedman Leah , David Renaud , Delva Fleur , Brocker Patrice , Yesavage Jerome , Robert Philippe Henri 
Published: June 2012

ObjectiveThis study aimed to evaluate the effectiveness of a nursing home (NH) staff education to manage apathy in older individuals with a diagnosis of dementia.MethodsSixteen NHs agreed to participate, and 230 demented apathetic residents were randomly assigned to the reference group (RG) or the intervention group (IG). IG received a month of weekly 4‐h training. Qualitative evaluation was performed through interviews and questionnaires regarding work practices and knowledge about dementia. Quantitative evaluation was at baseline, at the end of the training program (week 4), and 3 months after the end of it with the use of the Neuropsychiatric Inventory (NPI), the Apathy Inventory, and two observation scales.ResultsIn the qualitative evaluation, very few staff responded to the questionnaire. Concerning the difficulty that managing residents' behavioral symptoms presented, aggressiveness was ranked as the most difficult behavior to manage and apathy as the least difficult. In the quantitative evaluation, the results are as follows. NPI: the IG scores increased from baseline to week 4 more than the RG for symptoms belonging to the affective and the psychotic NPI item subgroup. Apathy Inventory: there was a significant decrease of the emotional blunting score dimension in the IG. Group Observation Scale: significant improvement was observed for the emotional blunting dimension in the IG only.ConclusionsApathy is rarely identified as a problem in NH. Emotional blunting was the only dimension sensitive to change. Failure to improve residents' level of interest could be explained by the difficulties encountered in accessing information regarding the subjects' personal interests. But it remains possible to modify residents' emotional reactivity and staff's perceptions of residents' behaviors and emotions. Copyright © 2012 John Wiley & Sons, Ltd.
PUMPS, GERMS AND STORAGE: THE IMPACT OF IMPROVED WATER CONTAINERS ON WATER QUALITY AND HEALTH
Authors: Günther Isabel , Schipper Youdi 
Published: June 2012

ABSTRACTApplying a randomized controlled trial, we study the impact of improved water transport and storage containers on the water quality and health of poor rural households. The results indicate that improved household water infrastructure improves water quality and health outcomes in an environment where point‐of‐source water quality is good but where recontamination is widespread, leading to unsafe point‐of‐use drinking water. Moreover, usage rates of 88% after 7 months are encouraging with regard to sustainable adoption. Our estimates suggest that the provision of improved household water infrastructure could ‘keep clean water clean’ at a cost of only 5% of the costs of providing households with improved public water supply. Given the general consensus in the literature that recontamination of water from improved public sources is a severe public health problem, improved transport and storage technologies appear to be an effective low‐cost supplement to the current standard of financing public water supply for poor rural communities. Copyright © 2012 John Wiley & Sons, Ltd.
Two New‐Skeleton Compounds from Sarcandra glabra
Authors: Li Xiong , Zhang Yu‐Feng , Zeng Xing , Liu Yi‐Ming , Feng Yi 
Published: June 2012

AbstractTwo new‐skeleton compounds, sarcaboside A (1) together with its artifact sarcaboside B (2), were isolated from the whole plant of Sarcandra glabra. Their structures were elucidated on the basis of extensive spectroscopic analysis as well as HR‐ESI‐MSn study.
The First One‐Pot, Solvent‐Free, Microwave‐Accelerated, Three‐Component Synthesis of Spirothiazolidin‐4‐ones via Staudinger/Aza‐Wittig Coupling/Cyclization
Authors: Ponnuswamy Alagusundaram , Shanmugavelan Poovan , Nagarajan Sangaraiah , Sathishkumar Murugan 
Published: June 2012

AbstractAn efficient and rapid, solvent‐free, microwave‐accelerated, one‐pot, three‐component protocol for the synthesis of spirothiazolidin‐4‐ones from organic azides is reported for the first time via Staudinger/aza‐Wittig coupling/cyclization. The solvent‐free approach overcomes the limitations associated with the prevailing solution‐phase methodologies in the case of amines. In particular, its novelty is that it eradicates the vital limitation, i.e., the accumulation of H2O (by‐product), which is known to affect the yield and rate of the reaction, thus affording the spirothiazolidin‐4‐ones in short reaction times in excellent yields.
Synthesis of Novel 8,14‐Secoursane Derivatives: Key Intermediates for the Preparation of Chiral Decalin Synthons from Ursolic Acid
Authors: Zhang Chongnan , Yang Haijun , Lü Guangying , Liu Cailin , Tang Yun , Liu Laibao 
Published: June 2012

AbstractThe novel 8,14‐secoursatriene derivative 6 was synthesized starting from ursolic acid (1) via methyl esterification of the 17‐carboxylic acid group and benzoylation of the 3‐hydroxy group (→2; Scheme 1), ozone oxidation of the C(12)C(13) bond (→3), dehydrogenation with Br2/HBr (→4), enol acetylation of the resulting carbonyl group (→5; Scheme 2), and ring‐C opening with the aid of UV light (→6). Ring‐C‐opened dienone derivative 7 of ursolic acid was also obtained via selective hydrolysis of 6 (Scheme 2). Both compounds 6 and 7 are key intermediates for the preparation of chiral decalin synthons from ursolic acid.
A New Cyclopeptide and Other Constituents from the Leaves of Zanthoxylum rigidumHumb. & Bonpl. ex Willd. (Rutaceae)
Authors: Ribeiro Tereza Auxiliadora Nascimento , da Silva Letícia Ricette , de Sousa Júnior Paulo Teixeira , Castro Rosane Nora , de Carvalho Mário Geraldo 
Published: June 2012

AbstractA new cyclopeptide, cyclozanthoxylane A (1), the lignans cis‐ and trans‐methylpluviatolide, the flavonoid isoquercitrin, along with a mixture of benzoic and cinnamic acid derivatives, were isolated from the MeOH extract of the leaves of Zanthoxylum rigidum (Rutaceae). The structures of the compounds were determined on the basis of 1D‐ and 2D‐NMR, and MS analysis. It is the first time that a natural cyclic peptide has been isolated from the genus Zanthoxylum.
Synthesis and Asymmetric Oxidation of (Caranylsulfanyl)‐1H‐imidazoles
Authors: Demakova Marina Y. , Sudarikov Denis V. , Rubtsova Svetlana A. , Frolova Larisa L. , Popov Alexey V. , Slepukhin Pavel A. , Kuchin Alexander V. 
Published: June 2012

AbstractFor the first time 2‐(cis‐caran‐4‐ylsulfanyl)‐1H‐imidazole, 1‐methyl‐2‐(cis‐caran‐4‐ylsulfanyl)‐1H‐imidazole, and 2‐(cis‐caran‐4‐ylsulfanyl)‐1H‐benzimidazole (carane=3,7,7‐trimethylbicyclo[4.1.0]heptane) were synthesized, and the asymmetric oxidation of these compounds was also carried out. It was shown that oxidation by the Bolm system and the modified system of Sharpless lead to corresponding sulfoxides with de values of 91–100%.
Isolation and Characterization of Novel Capsorubin‐Like Carotenoids from the Red Mamey (Pouteria sapota)
Authors: Murillo Enrique , Mosquera Yesury , Kurtán Tibor , Gulyás‐Fekete Gergely , Nagy Veronika , Deli József 
Published: June 2012

AbstractFrom the ripe fruits of red mamey (Pouteria sapota), two new carotenoids, 3′‐deoxycapsorubin and 3,3′‐dideoxycapsorubin, were isolated and identified based on their UV/VIS, CD, 1H‐NMR, and mass spectral data.
Regioselective Synthesis of 6‐[Chloro(difluoro)methyl]salicylates by [3+3] Cyclocondensations of 1,3‐Bis(trimethylsilyloxy)buta‐1,3‐dienes with 1‐Chloro‐1,1‐difluoro‐4‐(trimethylsilyloxy)pent‐3‐en‐2‐one
Authors: Erfle Silke , Reimann Sebastian , Bunescu Alina , Abilov Zharylkasyn A. , Spannenberg Anke , Langer Peter 
Published: June 2012

AbstractThe TiCl4‐mediated [3+3] cyclocondensation of various 1,3‐bis(trimethylsilyloxy)buta‐1,3‐dienes with 1‐chloro‐1,1‐difluoro‐4‐(trimethylsilyloxy)pent‐3‐en‐2‐one provides a regioselective access to novel 6‐(chlorodifluoromethyl)salicylates (=6‐(chlorodifluoromethyl)‐2‐hydroxybenzoates) with very good regioselectivity. For selected products, it was demonstrated that the CF2Cl group can be transformed to CF2H and CF2(Allyl) by free‐radical reactions.
Synthesis of Novel Disubstituted Pyrazolo[1,5‐a]pyrimidines, Imidazo[1,2‐a]pyrimidines, and Pyrimido[1,2‐a]benzimidazoles Containing Thioether and Aryl Moieties
Authors: Li Gang , Zhang Zun‐Ting , Dai Li‐Yan , Du Yin‐Li , Xue Dong 
Published: June 2012

AbstractA series of novel 6‐[(1,3,4‐thiadiazol‐2‐yl)sulfanyl]‐7‐phenylpyrazolo[1,5‐a]pyrimidines, 5‐phenyl‐6‐[(1,3,4‐thiadiazol‐2‐yl)sulfanyl]imidazo[1,2‐a]pyrimidines, and 2‐phenyl‐3‐[(1,3,4‐thiadiazol‐2‐yl)sulfanyl]pyrimido[1,2‐a]benzimidazoles have been synthesized in four steps starting with 2‐hydroxyacetophenone. The intermediate 3‐[(1,3,4‐thiadiazol‐2‐yl)sulfanyl]‐4H‐1‐benzopyran‐4‐ones reacted with pyrazol‐3‐amines, 5‐methylpyrazol‐3‐amine, and 1H‐imidazol‐2‐amine, 1H‐benzimidazol‐2‐amine via a cyclocondensation to give the title compounds in the presence of MeONa as base, respectively. The approach affords the target compounds in acceptable‐to‐good yields. The new compounds were characterized by their IR, NMR, and HR mass spectra.
MizorokiHeck and Sonogashira Cross‐Couplings Catalyzed by CNC Palladium Pincer Complexes in Organic and Aqueous Media
Authors: SanMartin Raul , Inés Blanca , Moure María Jesús , Herrero María Teresa , Domínguez Esther 
Published: June 2012

AbstractThe catalytic activity of two CNC palladium pincer complexes is evaluated in two fundamental CC bond‐forming reactions: MizorokiHeck and Sonogashira cross‐couplings. After several optimization attempts and a brief comparison with a PCN pincer catalyst, a number of arylated alkenes and diarylethynes are synthesized by procedures based on the catalytic use of the above mentioned CNC Pd pincers in H2O and DMF.
High‐throughput SNP‐based authentication of human cell lines
Authors: Castro Felipe , Dirks Wilhelm G. , Fähnrich Silke , Hotz‐Wagenblatt Agnes , Pawlita Michael , Schmitt Markus 
Published: June 2012

AbstractUse of false cell lines remains a major problem in biological research. Short tandem repeat (STR) profiling represents the gold standard technique for cell line authentication. However, mismatch repair (MMR)‐deficient cell lines are characterized by microsatellite instability, which could force allelic drifts in combination with a selective outgrowth of otherwise persisting side lines, and, thus, are likely to be misclassified by STR profiling. On the basis of the high‐throughput Luminex platform, we developed a 24‐plex single nucleotide polymorphism profiling assay, called multiplex cell authentication (MCA), for determining authentication of human cell lines. MCA was evaluated by analyzing a collection of 436 human cell lines from the German Collection of Microorganisms and Cell Cultures, previously characterized by eight‐loci STR profiling. Both assays showed a very high degree of concordance and similar average matching probabilities (∼1 × 10−8 for STR profiling and ∼1 × 10−9 for MCA). MCA enabled the detection of less than 3% of contaminating human cells. By analyzing MMR‐deficient cell lines, evidence was obtained for a higher robustness of the MCA compared to STR profiling. In conclusion, MCA could complement routine cell line authentication and replace the standard authentication STR technique in case of MSI cell lines.
Towards 3D modelling and imaging of infection scenarios at the single cell level using holographic optical tweezers and digital holographic microscopy
Authors: Kemper Björn , Barroso Álvaro , Woerdemann Mike , Dewenter Lena , Vollmer Angelika , Schubert Robin , Mellmann Alexander , von Bally Gert , Denz Cornelia 
Published: June 2012

AbstractThe analysis of dynamic interactions of microorganisms with a host cell is of utmost importance for understanding infection processes. We present a biophotonic holographic workstation that allows optical manipulation of bacteria by holographic optical tweezers and simultaneously monitoring of dynamic processes with quantitative multi‐focus phase imaging based on self‐interference digital holographic microscopy. Our results show that several bacterial cells, even with non‐spherical shape, can be aligned precisely on the surface of living host cells and localized reproducibly in three dimensions. In this way a new label‐free multipurpose device for modelling and quantitative analysis of infection scenarios at the single cell level is provided. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of the fetal bovine serum proteins on the growth of human osteoblast cells on graphene
Authors: Kalbacova Marie , Broz Antonin , Kalbac Martin 
Published: June 2012

AbstractThe influence of single‐layer graphene produced by chemical vapor deposition on human osteoblast cells under different conditions was studied. Measurements probed the ability of cells to adhere and proliferate on graphene compared with SiO2/Si substrates and standard tissue culture plastic when cells were incubated for the first 2 h in the presence or the absence of fetal bovine serum (FBS), thus influencing the initial, direct interaction of cells with the substrate. It was found that after 48 h of human osteoblast incubation on graphene films, there were a comparable number of cells of a similar size irrespective of the presence or the absence of serum proteins. On the other hand, a strong initial influence through the presence of FBS proteins on cell number and cell size was observed in the case of the SiO2/Si substrate and control plastic. Thus, our study showed that the initial presence/absence of FBS in the medium does not determine cell fate in the case of a graphene substrate, which is very unusual and different from the behavior of cells on other materials. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 100A:3001–3007, 2012.
In vitro mineralization and bone osteogenesis in poly(ε‐caprolactone)/gelatin nanofibers
Authors: Alvarez Perez Marco A. , Guarino Vincenzo , Cirillo Valentina , Ambrosio Luigi 
Published: June 2012

AbstractThe implementation of bio‐inspired strategies in developing scaffolds for the reconstruction of oral, craniofacial and bone skeletal tissues after injury or resection remains a challenge. Currently, advanced scaffolds comprising nanofibers endowed with biochemical/biophysical signaling capability offer great advantages in bone regeneration, because of their faithful mimesis of the characteristic size scales encountered in the fibrous network of the native extracellular matrix (ECM). In this study, we investigate the biological potential of nanofibers made of polycaprolactone and gelatin on guiding the regenerative mechanisms of bone. Contact angle measurements and environmental SEM investigations indicate a weak linkage of gelatin molecules to PCL chains, facilitating an efficient adhesion signal to cells up to 3 days of culture. In vitro studies performed on human mesenchymal stem cells (hMSC) until 3 weeks in culture medium with osteogenic supplementation, clearly showing the effectiveness of PCL/Gelatin electrospun scaffolds in promoting bone osteogenesis and mineralization. The increase of alkaline phosphatase activity (ALP) and gene expression of bone‐related molecules (bone sialoprotein, osteopontin and osteocalcin), indicated by immunodetection and upregulation level of mRNA, confirm that proposed nanofibers promote the osteogenic differentiation of hMSC, preferentially in osteogenic medium. Moreover, the evidence of newly formed collagen fibers synthesis by SIRCOL and their mineralization evaluated by Alizarin Red staining and EDS mapping of the elements Ca, P and Mg corroborate the idea that native osteoid matrix is ultimately deposited. All these data suggest that PCL and gelatin electrospun nanofibers have great potential as osteogenesis promoting scaffolds for successful application in bone surgery. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 100A:3008–3019, 2012.