bluuebunny/crossref_metadata_2025_split huggingface dataset:
Luminescence in Sr4Al14O25:Ce3+ aluminate phosphor
Authors: Nikhare G. N. , Gedam S. C. , Dhoble S. J. 
Published: June 2014

ABSTRACTCerium‐doped Sr4Al14O25 phosphor is prepared using a single‐step combustion synthesis and its X‐ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL) and thermoluminescence (TL) properties are characterized. XRD reveals the formation of the desired phase in the prepared sample. SEM micrographs of the prepared Sr4Al14O25 phosphor show that the particle size is 10 µm. The prepared Sr4Al14O25, along with Sr4Al14O25:Cex (x = 0.5–5 mol%) shows a PL emission peak at 314 nm under UV excitation of 262 nm wavelength due to 5d → 4f transition. The phosphor is suitable for higher concentrations of Ce ions. The TL glow peak reveals three clearly visible distinct peaks at temperatures around 130, 231 and 336ºC. The three peaks are separated by deconvolution and kinetic parameters calculated using Chen's peak shape method. The calculation shows that the reaction follows second‐order kinetics with activation energy (E) values of 0.52, 0.81 and 1.12 eV, and frequency factor (s) values of 5.58 × 105, 4.53 × 107 and 4.57 × 108 s‐1 for the three individual peaks. Copyright © 2014 John Wiley & Sons, Ltd.
In vivo protective effects of dietary curcumin and capsaicin against alcohol‐induced oxidative stress
Authors: Pyun Chang‐Won , Kim Ji‐Han , Han Kyu‐Ho , Hong Go‐Eun , Lee Chi‐Ho 
Published: June 2014

AbstractBALB/c mice were exposed to chronic alcohol‐induced oxidative stress by intragastric administration of excessive ethanol (5 g/kg body weight) during the 24‐week period. Curcumin (0.016%) or capsaicin (0.014%) containing diets were fed with or without ethanol treatment in four groups. There was no statistically significant difference in the behavioral test between all groups during the experimental period. Only one alcohol‐treated mouse fed a normal diet showed a behavioral disorder and died before the raising period was completed. There were no effects on the activity of catalase and superoxide dismutase in the brain. However, curcumin or capsaicin treatment prevented alcohol‐induced decline in brain weight. Furthermore, the levels of malondialdehyde and phosphatidylcholine hydroperoxide were significantly reduced in the brain tissue extract. The findings of this study demonstrated and confirmed the antioxidant effect of curcumin and capsaicin against alcohol‐induced oxidative stress, and they suggest a direction for further studies. © 2014 BioFactors, 40(5):494–500, 2014
Raman spectroscopy provides a rapid, non‐invasive method for quantitation of starch in live, unicellular microalgae
Authors: Ji Yuetong , He Yuehui , Cui Yanbin , Wang Tingting , Wang Yun , Li Yuanguang , Huang Wei E. , Xu Jian 
Published: June 2014

AbstractConventional methods for quantitation of starch content in cells generally involve starch extraction steps and are usually labor intensive, thus a rapid and non‐invasive method will be valuable. Using the starch‐producing unicellular microalga Chlamydomonas reinhardtii as a model, we employed a customized Raman spectrometer to capture the Raman spectra of individual single cells under distinct culture conditions and along various growth stages. The results revealed a nearly linear correlation (R2 = 0.9893) between the signal intensity at 478 cm–1 and the starch content of the cells. We validated the specific correlation by showing that the starch‐associated Raman peaks were eliminated in a mutant strain where the AGPase (ADP‐glucose pyrophosphorylase) gene was disrupted and consequentially the biosynthesis of starch blocked. Furthermore, the method was validated in an industrial algal strain of Chlorella pyrenoidosa. This is the first demonstration of starch quantitation in individual live cells. Compared to existing cellular starch quantitation methods, this single‐cell Raman spectra‐based approach is rapid, label‐free, non‐invasive, culture‐independent, low‐cost, and potentially able to simultaneously track multiple metabolites in individual live cells, therefore should enable many new applications.
Identification of critical parameters in liquid enzyme‐catalyzed biodiesel production
Authors: Nordblad Mathias , Silva Vanessa T. L. , Nielsen Per Munk , Woodley John M. 
Published: June 2014

ABSTRACTCallera™ Trans L, a liquid formulation of Thermomyces lanuginosus lipase, has recently shown great promise as a cost‐efficient catalyst for methanolysis of triglyceride substrates, specifically in the BioFAME process. However, identifying the right combination of temperature and concentrations of catalyst, water and methanol to realize the full potential of the reaction system has remained a challenge. This study presents an investigation of the impact of temperature, enzyme and water concentration on the reaction, as well as the effect of methanol feed rate for the conversion of rapeseed oil in a fed‐batch reaction system. It was observed that the reaction can be divided into two distinct parts. The first part of the reaction, during which primarily tri‐ and diglycerides are converted, proceeded at a high rate and thus required a high rate of methanol supply. The second part of the reaction, where the remaining di‐ and monoglycerides are converted, proceeded at a much lower rate. Consequently, it is necessary to reduce the methanol feed rate during the latter part of the reaction to avoid inhibition or even inactivation of the enzyme. Since the second part of the reaction occupied most of the 24‐h reaction time, it was concluded that this is the part of the process where further development efforts should be targeted. This point was demonstrated by partially substituting the catalyst with a lipase with a different specificity, which enhanced the performance during the second phase of the reaction. Biotechnol. Bioeng. 2014;111: 2446–2453. © 2014 Wiley Periodicals, Inc.
Analysis and pharmacokinetic study of polyphyllin H in beagle dog plasma after oral administration of Rhizoma Paridis extracts by LC‐MS/MS
Authors: Yin Xingbin , Lin Longfei , Shen Mingrui , Zhai Yujing , Cao Sali , Fu Jing , Li Xuechun , Yang Chunjing , Xia Zhenwen , Zhao Yang , Li Shangxin , Bai Ying , Xue Dan , Ni Jian 
Published: June 2014

ABSTRACTA highly sensitive, rapid assay method has been developed and validated for the analysis of polyphyllin H in beagle dog plasma with liquid chromatography coupled to tandem mass spectrometry with electrospray ionization in the positive‐ion mode. The assay procedure involves extraction of polyphyllin H and ginsenoside Re (IS) from beagle dog plasma. Chromatographic separation was carried out on an Agilent Zorbax XDB‐C18 (100 × 2.1 mm, 1.8μm) column by isocratic elution with acetonitrile and water (50:50, v/v) at a flow rate of 0.25 mL/min with a total run time of 2.5 min. The MS/MS ion transitions monitored were 870.46 → 869.6 for polyphyllin H and 947.12 → 969.60 for IS. Linear responses were obtained for polyphyllin H ranging from 1 to 50 ng/mL. The intra‐and inter‐day precisions (RSDs) were <1.77 and 3.39% and the extraction recovery ranged from 91.89 to 93.33% with RSD <2.68%. Stability studies showed that polyphyllin H was stable in the preparation and analytical process. The results indicated that the validated method was successfully used to determine the concentration–time profiles of polyphyllin H. Copyright © 2014 John Wiley & Sons, Ltd.
A systematic review of microRNA expression profiling studies in human gastric cancer
Authors: Shrestha Sirjana , Hsu Sheng‐Da , Huang Wei‐Yun , Huang Hsi‐Yuan , Chen WenLiang , Weng Shun‐Long , Huang Hsien‐Da 
Published: June 2014

AbstractGastric cancer (GC) is the second leading cause of global cancer mortality. Most GC patients are diagnosed with advanced‐stage disease and show extremely poor prognosis. All of the GC research has a common interest to search for the specific and sensitive biomarkers for early diagnosis of GC. Number of microRNAs play important role in GC. We carried out a systematic review of published miRNA profiling studies that compared the miRNA expression profiles between GC tissues and paired noncancerous gastric tissue. A vote‐counting strategy was followed with the collection of information like total number of studies reporting differential expression of miRNA, total number of tissue samples used in the studies, direction of differential expression and fold change. A total of 352 differentially expressed microRNAs were reported in the 14 microRNA expression profiling studies that compared GC tissues with normal tissues with 120 microRNAs reported at least in two studies. In the group of consistently reported microRNAs, miR‐21 was reported upregulated in 10 studies followed by miR‐25, miR‐92, and miR‐223 upregulated in eight studies. MiR‐375 and miR‐148a were found downregulated in six and five studies, respectively, followed by miR‐638 in four studies. MiR‐107 and miR‐103 were reported in nine and eight studies, respectively, but their expression were inconsistent. From this study, the most consistently reported upregulated microRNA was found to be miR‐21. This systematic review study of human GC microRNA expression profiling studies would provide information on microRNAs with potential role as the biomarkers in gastric cancer.
African American women's perceptions of cancer clinical trials
Authors: Haynes‐Maslow Lindsey , Godley Paul , Dimartino Lisa , White Brandolyn , Odom Janice , Richmond Alan , Carpenter William 
Published: June 2014

AbstractCancer clinical trials are important for resolving cancer health disparities for several reasons; however, clinical trial participation among African Americans is significantly lower than Caucasians. This study engaged focus groups of 82 female African American cancer survivors or cancer caregivers, including those in better resourced, more urban areas and less resourced, more rural areas. Informed by an integrated conceptual model, the focus groups examined perceptions of cancer clinical trials and identified leverage points that future interventions may use to improve enrollment rates. Study findings highlight variation in community knowledge regarding cancer clinical trials, and the importance of community education regarding clinical trials and overcoming historical stigma associated with clinical research specifically and the health care system more generally. Study participants commented on the centrality of churches in their communities, and thus the promise of the church as loci of such education. Findings also suggested the value of informed community leaders as community information sources, including community members who have a previous diagnosis of cancer and clinical trial experience. The sample size and location of the focus groups may limit the generalizability of the results. Since the women in the focus groups were either cancer survivors or caregivers, they may have different experiences than nonparticipants who lack the close connection with cancer. Trust in the health system and in one's physician was seen as important factors associated with patient willingness to enroll in clinical trials, and participants suggested that physicians who were compassionate and who engaged and educated their patients would build important trust requisite for patient participation in clinical trials.
In Vivo Structure–Activity Relationship Studies Support Allosteric Targeting of a Dual Specificity Phosphatase
Authors: Korotchenko Vasiliy N. , Saydmohammed Manush , Vollmer Laura L. , Bakan Ahmet , Sheetz Kyle , Debiec Karl T. , Greene Kristina A. , Agliori Christine S. , Bahar Ivet , Day Billy W. , Vogt Andreas , Tsang Michael 
Published: June 2014

AbstractDual specificity phosphatase 6 (DUSP6) functions as a feedback attenuator of fibroblast growth factor signaling during development. In vitro high throughput chemical screening attempts to discover DUSP6 inhibitors have yielded limited success. However, in vivo whole‐organism screens of zebrafish identified compound 1 (BCI) as an allosteric inhibitor of DUSP6. Here we designed and synthesized a panel of analogues to define the structure–activity relationship (SAR) of DUSP6 inhibition. In vivo high‐content analysis in transgenic zebrafish, coupled with cell‐based chemical complementation assays, identified structural features of the pharmacophore of 1 that were essential for biological activity. In vitro assays of DUSP hyperactivation corroborated the results from in vivo and cellular SAR. The results reinforce the notion that DUSPs are druggable through allosteric mechanisms and illustrate the utility of zebrafish as a model organism for in vivo SAR analyses.
Rhamnose Glycoconjugates for the Recruitment of Endogenous Anti‐Carbohydrate Antibodies to Tumor Cells
Authors: Sheridan Rachael T. C. , Hudon Jonathan , Hank Jacquelyn A. , Sondel Paul M. , Kiessling Laura L. 
Published: June 2014

AbstractImmunotherapy is a promising strategy for targeting tumors. One emerging approach is to harness the immune effector functions of natural antibodies to destroy tumor cells. Dinitrophenyl (DNP) and the galactose‐α‐1,3‐galactose (αGal) epitope are two haptens that bind endogenous antibodies. One potential alternative is the deoxysugar L‐rhamnose. We compared these candidates by using a biosensor assay to evaluate human sera for endogenous antibody concentration, antibody isotype distribution, and longevity of antibody–hapten interactions. Antibodies recognizing α‐rhamnose are of equal or greater abundance and affinity as those recognizing αGal. Moreover, both rhamnose and αGal epitopes are more effective than DNP at recruiting the IgG antibody subtype. Exposure of tumor cells to rhamnose‐bearing glycolipids and human serum promotes complement‐mediated cytotoxicity. These data highlight the utility of α‐rhamnose‐containing glycoconjugates to direct the immune system to target cells.
Copper‐Free Click Reactions with Polar Bicyclononyne Derivatives for Modulation of Cellular Imaging
Authors: Leunissen E. H. P. , Meuleners M. H. L. , Verkade J. M. M. , Dommerholt J. , Hoenderop J. G. J. , van Delft F. L. 
Published: June 2014

AbstractThe ability of cells to incorporate azidosugars metabolically is a useful tool for extracellular glycan labelling. The exposed azide moiety can covalently react with alkynes, such as bicyclo[6.1.0]nonyne (BCN), by strain‐promoted alkyne–azide cycloaddition (SPAAC). However, the use of SPAAC can be hampered by low specificity of the cycloalkyne. In this article we describe the synthesis of more polar BCN derivatives and their properties for selective cellular glycan labelling. The new polar derivatives [amino‐BCN, glutarylamino‐BCN and bis(hydroxymethyl)‐BCN] display reaction rates similar to those of BCN and are less cell‐permeable. The labelling specificity in HEK293 cells is greater than that of BCN, as determined by confocal microscopy and flow cytometry. Interestingly, amino‐BCN appears to be highly specific for the Golgi apparatus. In addition, the polar BCN derivatives label the N‐glycan of the membrane calcium channel TRPV5 in HEK293 cells with significantly enhanced signal‐to‐noise ratios.
Surface Control and Photocatalytic Activity of Branched Silver Orthophosphate Dendrites
Authors: Wang Jun , Lou Sunqi , Sun Peng , Wang LiLi , Teng Yiran , Chen Mindong , Teng Fei 
Published: June 2014

AbstractSurface control is important to improve the adsorption, reactivity, and selectivity of materials. Limited by thermodynamic crystal habit, however, it is still a big challenge to control active surfaces simply and effectively. In this report, we introduce an innovative branching‐growth methodology to control the surfaces of Ag3PO4 without the use of screening agents or templates. Typically, an in situ seed‐induced branching growth strategy is developed to achieve the surface control of silver orthophosphate, in which the crystal growth changes from mass‐transport‐limited branching growth to pH‐dependent faceting growth. As a result, numerous unprecedented, highly branched Ag3PO4 dendrites have been acquired. The apparent reaction rate constants of these dendrites are 2.55–3.76 times higher than conventional cubes for the degradation of rhodamine B dye. This study provides a new, effective avenue to control the surfaces of materials, which has made a big breakthrough to the improvement of the performances of materials. This is important for us to obtain materials or devices with greatly improved performances.
Evidences of Two‐Regimes in the Measurement of Ru Particle Size Effect for CO Dissociation during Fischer–Tropsch Synthesis
Authors: González‐Carballo Juan M. , Pérez‐Alonso Francisco J. , Ojeda Manuel , García‐García F. Javier , Fierro José Luis G. , Rojas Sergio 
Published: June 2014

AbstractThis work assesses the effect of the particle size for the Fischer–Tropsch synthesis with catalysts based on Ru particles between 4 and 71 nm. CO dissociation is a structure‐sensitive reaction, that is, the turnover frequency (TOF) is affected by Ru particle size. Herein it is demonstrated that two regimes exist for the effect of Ru particle size. On the one hand, the expected relationship of TOF with particle size, that is, the TOF increases with Ru particles <10 nm, is only observed if measured at steady‐state conditions. On the contrary, the TOF increases constantly with Ru particle size if measured at the initial state. However, the TOF measured for catalysts with Ru particles >10 nm declines during time on stream. These observations suggest that two regimes for the measurement of CO dissociation exist during Fischer–Tropsch synthesis. The reason for this is that two sites for CO dissociation on the Ru particles >10 nm exist at the initial state, terraces and step‐edges, but the latter ones deactivate during time on stream.
Sterilization of Medical Products from Collagen by Means of Supercritical CO2
Authors: Herdegen Volker , Felix Alexander , Haseneder Roland , Repke Jens‐Uwe , Leppchen‐Fröhlich Kathrin , Prade Ina , Meyer Michael 
Published: June 2014

AbstractCollagen is increasingly used as material for medical devices because of its excellent biocompatibility. To achieve long‐term durability, the collagen materials are dried and subsequently sterilized. Most common sterilization methods are unsuitable as they cause denaturation. Currently, only ethylenoxide or γ irradiation preserves the microscopic and macroscopic collagen structure. However, both methods require high safety standards and include the risk of uncontrolled crosslinking or cleavage of protein chains. Here, supercritical carbon dioxide is used for the sterilization of different collagen devices. Thereby, the influence of pressure, temperature, sterilization aid and dosage, and different operation modes is determined. The method is a promising alternative to existing sterilization techniques.
Porous Perovskite Fibers – Preparation by Wet Phase Inversion Spinning and Catalytic Activity
Authors: Kaiser Sandy , Reichelt Erik , Gebhardt Sylvia E. , Jahn Matthias , Michaelis Alexander 
Published: June 2014

AbstractPorous perovskite (LaMnO3) fibers were prepared by means of wet phase inversion spinning. The influence of different spinning procedures, slurry and coagulation bath composition on fiber shape and pore morphology was studied. The catalytic activity of the prepared fibers was tested for carbon monoxide oxidation as a model reaction in a differential recycle reactor. The results revealed that by suitable choice of process conditions porous catalytically active fibers can be prepared. Catalytic measurements confirmed that the catalytic fibers exhibit an open structure that allows full utilization of the catalytically active surface without intraparticle diffusional limitations.
Multielectron, Multistep Molecular Catalysis of Electrochemical Reactions: Benchmarking of Homogeneous Catalysts
Authors: Costentin Cyrille , Savéant Jean‐Michel 
Published: June 2014

AbstractCurrent–potential responses in cyclic voltammetry and in preparative‐scale electrolysis are established for two‐electron two‐step homogeneous molecular catalysis after systematic categorization of the various possible reaction schemes. They allow the derivation of catalytic Tafel plots, reflecting the intrinsic properties of the catalysts independent of contingent electrolysis parameters. They serve as a rational basis for benchmarking catalysts of the same electrochemical reaction within the same log(turnover frequency) versus overpotential plane of merit.
Exploring Strain‐Promoted 1,3‐Dipolar Cycloadditions of End Functionalized Polymers
Authors: Ledin Petr A. , Kolishetti Nagesh , Hudlikar Manish S. , Boons Geert‐Jan 
Published: June 2014

AbstractStrain‐promoted 1,3‐dipolar cycloaddition of cyclooctynes with 1,3‐dipoles such as azides, nitrones, and nitrile oxides, are of interest for the functionalization of polymers. In this study, we have explored the use of a 4‐dibenzocyclooctynol (DIBO)‐containing chain transfer agent in reversible addition–fragmentation chain transfer polymerizations. The controlled radical polymerization resulted in well‐defined DIBO‐terminating polymers that could be modified by 1,3‐dipolar cycloadditions using nitrones, nitrile oxides, and azides having a hydrophilic moiety. The self‐assembly properties of the resulting block copolymers have been examined. The versatility of the methodology was further demonstrated by the controlled preparation of gold nanoparticles coated with the DIBO‐containing polymers to produce materials that can be further modified by strain‐promoted cycloadditions.
The Donor‐Stabilized Silylene Bis[N,N′‐diisopropylbenzamidinato(−)]silicon(II): Synthesis, Electronic Structure, and Reactivity
Authors: Junold Konstantin , Nutz Marco , Baus Johannes A. , Burschka Christian , Fonseca Guerra Célia , Bickelhaupt F. Matthias , Tacke Reinhold 
Published: June 2014

AbstractA convenient and robust synthesis of bis[N,N′‐diisopropylbenzamidinato(−)]silicon(II) (1), a donor‐stabilized silylene, has been developed (35 g scale). To get further information about the reactivity profile of 1, a series of oxidative addition reactions were studied. Treatment of 1 with PhSeSePh (SeSe bond activation), C6F6 (CF activation), and CO2 (CO activation/cycloaddition) yielded the neutral six‐coordinate silicon(IV) complexes 10, 11, and 13, respectively. Treatment of 1 with N2O resulted in the formation of the dinuclear five‐coordinate silicon(IV) complex 12 (oxidative addition/dimerization), which contains a four‐membered Si2O2 ring. Compounds 10–13 were characterized by NMR spectroscopic studies in the solid state and in solution and by crystal structure analyses. Silylene 1 is three‐coordinate in the solid state (from crystal structure analysis) and exists as the four‐coordinate isomer 1′ in benzene solution (from computational studies). Based on state‐of‐the‐art relativistic DFT analyses, the four‐coordinate species 1′ was demonstrated to be the thermodynamically favored isomer in benzene solution (favored by ΔG=6.6 kcal mol−1 over the three‐coordinate species 1). The reason for this was studied by bonding analyses of 1 and 1′. Furthermore, the 29Si NMR chemical shifts of 1 and 1′ were computed, and in the case of 1′ it was analyzed how this NMR spectroscopic parameter is affected by solvation. These studies further supported the assumption that the silylene is four‐coordinate in solution.
ChemInform Abstract: Perovskite‐Based Hybrid Solar Cells Exceeding 10% Efficiency with High Reproducibility Using a Thin Film Sandwich Approach.
Authors: Conings Bert , Baeten Linny , De Dobbelaere Christopher , D'Haen Jan , Manca Jean , Boyen Hans‐Gerd 
Published: June 2014

AbstractHybrid solar cells based on the mixed metal halide perovskite absorber MeNH3PbI2Cl, sandwiched between selective contacts of TiO2 and poly‐3‐hexylthiophene show unprecedented reproducibility with efficiencies up to 10.8%.
Künstliche Nukleinsäure als molekulare Schere
Authors: Feil Sylvia 
Published: June 2014

AbstractSpiegelbildliche Enzyme aus Nukleinsäuren zerschneiden RNA‐Moleküle gezielt und schalten sie damit aus. Werden Krankheiten durch überexprimierte Gene verursacht, könnten diese Spiegelzyme ein neues Werkzeug zum Gene‐Silencing sein [1].