bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chemoenzymatic Synthesis of Trehalose Analogues: Rapid Access to Chemical Probes for Investigating Mycobacteria
Authors: Urbanek Bailey L. , Wing Douglas C. , Haislop Krystal S. , Hamel Chelsey J. , Kalscheuer Rainer , Woodruff Peter J. , Swarts Benjamin M. 
Published: August 2014

AbstractTrehalose analogues are emerging as valuable tools for investigating Mycobacterium tuberculosis, but progress in this area is slow due to the difficulty in synthesizing these compounds. Here, we report a chemoenzymatic synthesis of trehalose analogues that employs the heat‐stable enzyme trehalose synthase (TreT) from the hyperthermophile Thermoproteus tenax. By using TreT, various trehalose analogues were prepared quickly (1 h) in high yield (up to >99 % by HPLC) in a single step from readily available glucose analogues. To demonstrate the utility of this method in mycobacteria research, we performed a simple “one‐pot metabolic labeling” experiment that accomplished probe synthesis, metabolic labeling, and imaging of M. smegmatis in a single day with only TreT and commercially available materials.
Superparamagnetic CuFeO2 Nanoparticles in Deep Eutectic Solvent: an Efficient and Recyclable Catalytic System for the Synthesis of Imidazo[1,2‐a]pyridines
Authors: Lu Jun , Li Xiao‐Tang , Ma Er‐Qian , Mo Li‐Ping , Zhang Zhan‐Hui 
Published: August 2014

AbstractSuperparamagnetic CuFeO2 nanoparticles were prepared and characterized by XRD, SEM, TEM, FRIR spectroscopy, and vibrating sample magnetometry techniques. The catalytic activity of CuFeO2 nanoparticles was investigated in the one‐pot, three‐component reaction of 2‐aminopyridines, aldehydes, and alkynes using citric acid–dimethylurea melt as a green solvent. An array of imidazo[1,2‐a]pyridines were obtained in good to excellent yields. The catalytic system can be successfully reused six times with keeping its catalytic performance.
Greenhouse Gas Mitigation Costs of Synthetic Methane and Methanol from Biomass and Coal
Authors: Rönsch S. , Zeymer M. , Majer S. 
Published: August 2014

AbstractZur Bereitstellung von Sekundärenergieträgern wie Methan und Methanol ist die gemeinsame Nutzung von Kohle und Biomasse in Co‐Vergasungsanlagen eine Alternative zu Erdöl. Trotz der anfallenden Mehrkosten könnte die Einsparung von CO2‐Zertifikaten beim Einsatz von Biomasse einen wirtschaftlichen Anreiz bieten. Hier werden daher die CO2‐Zertifikatepreise abgeschätzt, bei denen die Produktion von Methanol und Methan in Europa ökonomisch wettbewerbsfähig ist. Dazu werden Massen‐ und Energiebilanzen berechnet und die Treibhausgasvermeidungskosten ausgewiesen.
Chance Constrained Optimization of Booster Chlorination in Water Distribution Networks
Authors: Köker Ezgi , Altan‐Sakarya A. Burcu 
Published: August 2014

AbstractQuality of municipal water is sustained by addition of disinfectant, generally chlorine, to the water distribution network. Because of health problems, chlorine concentration in the network is limited between maximum and minimum limits. Carcinogenic disinfectant by‐products start to occur at high concentrations so it is desired to have minimum amount of chlorine without violating the limit. In addition to the health issues, minimum injection amount is favorable concerning cost. Hence, an optimization problem which covers all of these considerations should be modeled. However, there are uncertain factors as chlorine is reactive and decays both over time and space. Thus, probabilistic approach is necessary to obtain reliable and realistic results from the model. In this study, a linear programming model is developed for the chance constrained optimization of the water distribution network. The objective is to obtain minimum amount of injection mass subjected to maintaining more uniformly distributed chlorine concentrations within the limits, while considering the randomness of chlorine concentration by probability distributions. Network hydraulics and chlorine concentration are computed by the network simulation software, EPANET.
Diagnostic and prognostic value of preoperative combined GFAP, IGFBP‐2, and YKL‐40 plasma levels in patients with glioblastoma
Authors: Gállego Pérez‐Larraya Jaime , Paris Sophie , Idbaih Ahmed , Dehais Caroline , Laigle‐Donadey Florence , Navarro Soledad , Capelle Laurent , Mokhtari Karima , Marie Yannick , Sanson Marc , Hoang‐Xuan Khê , Delattre Jean‐Yves , Mallet Alain 
Published: August 2014

BACKGROUNDCirculating proteins released by tumor cells have recently been investigated as potential single surrogate biomarkers for glioblastoma multiforme (GBM). The aim of the current hypothesis‐generating study was to evaluate the diagnostic and prognostic role of preoperative insulin‐like growth factor‐binding protein 2 (IGFBP‐2), chitinase‐3‐like protein 1 (YKL‐40), and glial fibrillary acidic protein (GFAP) plasma levels in patients with GBM, both as single markers and as a combined profile.METHODSPlasma samples from 111 patients with GBM and a subset of 40 patients with nonglial brain tumors were obtained preoperatively. Plasma from 99 healthy controls was also analyzed. IGFBP‐2, YKL‐40, and GFAP levels were determined using enzyme‐linked immunoadsorbent assay tests. Their association with histological and radiological variables was assessed.RESULTSCirculating levels of all 3 proteins were found to be significantly higher in patients with GBM compared with healthy controls (P < .01). Only YKL‐40 and GFAP were found to demonstrate significant differences between patients with GBM and nonglial brain tumors (P = .04). GFAP was undetectable (<0.02 ng/mL) in all patients without GBM. A receiver operating characteristic analysis accounting for a 2‐step diagnostic procedure including the 3 biomarkers afforded an area under the curve of 0.77 for differentiating patients with GBM from those with nonglial brain tumors. There was a significant correlation between tumor volume and plasma IGFBP‐2 level (Spearman Rho correlation coefficient, 0.22; P = .025) and GFAP (Spearman Rho correlation coefficient, 0.36; P < .001) among patients with GBM. Preoperative plasma IGFBP‐2 levels were found to be independently associated with worse overall survival among patients with GBM (hazard ratio, 1.3; P = .05).CONCLUSIONSA combined profile of preoperative IGFBP‐2, GFAP, and YKL‐40 plasma levels could serve as an additional diagnostic tool for patients with inoperable brain lesions suggestive of GBM. In addition, IGFBP‐2 levels appear to constitute an independent prognostic factor in patients with GBM. Cancer 2014;120:3972–3980. © 2014 American Cancer Society.
Investigating the Thermostability of Succinate: Quinone Oxidoreductase Enzymes by Direct Electrochemistry at SWNTs‐Modified Electrodes and FTIR Spectroscopy
Authors: Melin Frederic , Noor Mohamed R. , Pardieu Elodie , Boulmedais Fouzia , Banhart Florian , Cecchini Gary , Soulimane Tewfik , Hellwig Petra 
Published: August 2014

AbstractSuccinate: quinone reductases (SQRs) are the enzymes that couple the oxidation of succinate and the reduction of quinones in the respiratory chain of prokaryotes and eukaryotes. Herein, we compare the temperature‐dependent activity and structural stability of two SQRs, the first from the mesophilic bacterium Escherichia coli and the second from the thermophilic bacterium Thermus thermophilus, using a combined electrochemical and infrared spectroscopy approach. Direct electron transfer was achieved with full membrane protein complexes at single‐walled carbon nanotube (SWNT)‐modified electrodes. The possible structural factors that contribute to the temperature‐dependent activity of the enzymes and, in particular, to the thermostability of the Thermus thermophilus SQR are discussed.
Diglycerol‐Based Polyesters: Melt Polymerization with Hydrophobic Anhydrides
Authors: Dakshinamoorthy Deivasagayam , Weinstock Allison K. , Damodaran Krishnan , Iwig David F. , Mathers Robert T. 
Published: August 2014

AbstractThe melt polymerization of diglycerol with bicyclic anhydride monomers derived from a naturally occurring monoterpene provides an avenue for polyesters with a high degree of sustainability. The hydrophobic anhydrides are synthesized at ambient temperature via a solvent‐free Diels–Alder reaction of α‐phellandrene with maleic anhydride. Subsequent melt polymerizations with tetra‐functional diglycerol are effective under a range of [diglycerol]/[anhydride] ratios. The hydrophobicity of α‐phellandrene directly impacts the swelling behavior of the resulting polyesters. The low E factors (<2), large amount of bio‐based content (>75 %), ambient temperature monomer synthesis, and polymer degradability represent key factors in the design of these sustainable polyesters.
Tethering Metal Ions to Photocatalyst Particulate Surfaces by Bifunctional Molecular Linkers for Efficient Hydrogen Evolution
Authors: Yu Weili , Isimjan Tayirjan , Gobbo Silvano Del , Anjum Dalaver H. , Abdel‐Azeim Safwat , Cavallo Luigi , Garcia‐Esparza Angel T. , Domen Kazunari , Xu Wei , Takanabe Kazuhiro 
Published: August 2014

AbstractA simple and versatile method for the preparation of photocatalyst particulates modified with effective cocatalysts is presented; the method involves the sequential soaking of photocatalyst particulates in solutions containing bifunctional organic linkers and metal ions. The modification of the particulate surfaces is a universal and reproducible method because the molecular linkers utilize strong covalent bonds, which in turn result in modified monolayer with a small but controlled quantity of metals. The photocatalysis results indicated that the CdS with likely photochemically reduced Pd and Ni, which were initially immobilized via ethanedithiol (EDT) as a linker, were highly efficient for photocatalytic hydrogen evolution from Na2S‐Na2SO3‐containing aqueous solutions. The method developed in this study opens a new synthesis route for the preparation of effective photocatalysts with various combinations of bifunctional linkers, metals, and photocatalyst particulate materials.
Efficient Water‐Splitting Device Based on a Bismuth Vanadate Photoanode and Thin‐Film Silicon Solar Cells
Authors: Han Lihao , Abdi Fatwa F. , van de Krol Roel , Liu Rui , Huang Zhuangqun , Lewerenz Hans‐Joachim , Dam Bernard , Zeman Miro , Smets Arno H. M. 
Published: August 2014

AbstractA hybrid photovoltaic/photoelectrochemical (PV/PEC) water‐splitting device with a benchmark solar‐to‐hydrogen conversion efficiency of 5.2 % under simulated air mass (AM) 1.5 illumination is reported. This cell consists of a gradient‐doped tungsten–bismuth vanadate (W:BiVO4) photoanode and a thin‐film silicon solar cell. The improvement with respect to an earlier cell that also used gradient‐doped W:BiVO4 has been achieved by simultaneously introducing a textured substrate to enhance light trapping in the BiVO4 photoanode and further optimization of the W gradient doping profile in the photoanode. Various PV cells have been studied in combination with this BiVO4 photoanode, such as an amorphous silicon (a‐Si:H) single junction, an a‐Si:H/a‐Si:H double junction, and an a‐Si:H/nanocrystalline silicon (nc‐Si:H) micromorph junction. The highest conversion efficiency, which is also the record efficiency for metal oxide based water‐splitting devices, is reached for a tandem system consisting of the optimized W:BiVO4 photoanode and the micromorph (a‐Si:H/nc‐Si:H) cell. This record efficiency is attributed to the increased performance of the BiVO4 photoanode, which is the limiting factor in this hybrid PEC/PV device, as well as better spectral matching between BiVO4 and the nc‐Si:H cell.
Genome size estimates for crustaceans using Feulgen image analysis densitometry of ethanol‐preserved tissues
Authors: Jeffery Nicholas W. , Gregory T. Ryan 
Published: August 2014

AbstractCrustaceans are enormously diverse both phylogenetically and ecologically, but they remain substantially underrepresented in the existing genome size database. An expansion of this dataset could be facilitated if it were possible to obtain genome size estimates from ethanol‐preserved specimens. In this study, two tests were performed in order to assess the reliability of genome size data generated using preserved material. First, the results of estimates based on flash‐frozen versus ethanol‐preserved material were compared across 37 species of crustaceans that differ widely in genome size. Second, a comparison was made of specimens from a single species that had been stored in ethanol for 1–14 years. In both cases, the use of gill tissue in Feulgen image analysis densitometry proved to be a very viable approach. This finding is of direct relevance to both new studies of field‐collected crustaceans as well as potential studies based on existing collections. © 2014 International Society for Advancement of Cytometry
Demographic histories and genetic diversities of Fennoscandian marine and landlocked ringed seal subspecies
Authors: Nyman Tommi , Valtonen Mia , Aspi Jouni , Ruokonen Minna , Kunnasranta Mervi , Palo Jukka U. 
Published: August 2014

AbstractIsland populations are on average smaller, genetically less diverse, and at a higher risk to go extinct than mainland populations. Low genetic diversity may elevate extinction probability, but the genetic component of the risk can be affected by the mode of diversity loss, which, in turn, is connected to the demographic history of the population. Here, we examined the history of genetic erosion in three Fennoscandian ringed seal subspecies, of which one inhabits the Baltic Sea ‘mainland’ and two the ‘aquatic islands’ composed of Lake Saimaa in Finland and Lake Ladoga in Russia. Both lakes were colonized by marine seals after their formation c. 9500 years ago, but Lake Ladoga is larger and more contiguous than Lake Saimaa. All three populations suffered dramatic declines during the 20th century, but the bottleneck was particularly severe in Lake Saimaa. Data from 17 microsatellite loci and mitochondrial control‐region sequences show that Saimaa ringed seals have lost most of the genetic diversity present in their Baltic ancestors, while the Ladoga population has experienced only minor reductions. Using Approximate Bayesian computing analyses, we show that the genetic uniformity of the Saimaa subspecies derives from an extended founder event and subsequent slow erosion, rather than from the recent bottleneck. This suggests that the population has persisted for nearly 10,000 years despite having low genetic variation. The relatively high diversity of the Ladoga population appears to result from a high number of initial colonizers and a high post‐colonization population size, but possibly also by a shorter isolation period and/or occasional gene flow from the Baltic Sea.
Oxidation and structural decomposition of fats and oils at elevated temperatures
Authors: Gertz Christian , Aladedunye Felix , Matthäus Bertrand 
Published: August 2014

In the present work a fast and reliable laboratory protocol allowing a holistic statement about thermo‐oxidative structural changes of fats and oils at ambient temperatures, under accelerated conditions using 110°C and under elevated temperature usually used for frying at 170°C is proposed. The results demonstrate that two different routes of degradation may be responsible for fat deterioration at elevated temperatures. Depending on the temperature (at 20, 110, or 170°C) the composition of polar compounds changed. The content of di‐ and polymerized TAGs increased with time at elevated temperature, e.g., frying whereas the formation of oxidized products dominates at 110°C or lower. These different reaction mechanisms may explain the discrepancy between practical experiences during frying and the estimated oxidative resistance of fats and oils using accelerated tests like Rancimat or OSI.Practical applications: Both the amount of total oxidized monomeric TAGs called total oxidized products (TOP) and the amount of di‐ and polymerized TAGs (DPTG) can be used to describe the fat degradation at all stages. These parameters are less dependent on the fat composition but proportional to the heating time and applied temperature. A procedure is proposed to compare thermal and oxidative stability of vegetable oils and effectiveness of oxidative stabilizing agents.Heating apparatus to simulate fat degradation at 110 and 170°C with and without access of oxygen (20 L/h) to monitor oxidation and structural decomposition of fats and oils.
Construction of an Electrochemical Cell System Based on Carbon Composite Film Electrodes and its Application for Voltammetric Determination of Triclosan
Authors: Libansky Milan , Zima Jiri , Barek Jiri , Dejmkova Hana 
Published: August 2014

AbstractAn array of carbon composite electrodes embedded in a 96 well microtitration plate was fabricated and applied for DPV determination of the environmental pollutant triclosan (5‐chloro‐2‐(2,4‐dichlorophenoxy)‐phenol). For the preparation of composite electrodes, graphite and glassy carbon conductive microparticles were tested in combination with several types of polymers as nonconductive binders. For the measurements, combinations of graphitic carbon particles with polystyrene (C‐PS) and with polycarbonate (C‐PC) were selected. The achieved limit of detection was 0.49 µmol L−1 for C‐PS electrodes and 0.25 µmol L−1 for C‐PC electrodes in the selected optimum medium. The method was successfully applied for practical samples of river water and toothpaste.
Development of a Simple and Fast Electrochemical Method for Screening and Stoichiometric Determination of Dimenhydrinate
Authors: Machado Freitas Jhonys , da Costa Oliveira Thiago , Silva Polyana Luiza , Tofanello Gimenes Denise , Abarza Munoz Rodrigo Alejandro , Richter Eduardo Mathias 
Published: August 2014

AbstractDimenhydrinate (DIM) is a salt composed by the combination of two active pharmaceutical ingredients: diphenhydramine (DIP) and 8‐chlorotheophylline (CTP). In this work, the use of batch injection analysis with multiple pulse amperometric detection (BIA‐MPA) was proposed for the first time for fast stoichiometric determination of DIM. DIP (cation) and CTP (anion) were determined simultaneously in pharmaceutical samples with a simple and fast injection procedure (70 injections h−1). Additional strategies were also proposed for rapid screening of samples containing the DIM salt. By a simple injection of a sample into the BIA system (without using of calibration curve), reliable information about stoichiometry of the DIM salt (1 : 1; DIP:CTP) and presence or absence of interfering species (electroactive) can be achieved.
Associations between Liver Enzymes, Psychopathological and Clinical Features in Eating Disorders
Authors: Lelli Lorenzo , Castellini Giovanni , Gabbani Tommaso , Godini Lucia , Rotella Francesco , Ricca Valdo 
Published: August 2014

AbstractElevated aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels are frequently reported in patients with anorexia nervosa (AN) and in subjects who are overweight or with hyperlipidemia, which can be found to be associated with binge eating disorder (BED) and bulimia nervosa (BN). Liver functioning and psychopathological features have been evaluated in 43 patients with AN, 33 with BN, and 32 with BED. Body mass index was found to be inversely associated with AST and ALT in AN, and directly associated with AST and ALT in BED. A positive association between ALT and AST and body shape concern in AN was observed. Liver enzymes could be considered as an index of severity in AN and BED patients. Copyright © 2014 John Wiley & Sons, Ltd and Eating Disorders Association.
THE WELFARE IMPACT OF PARALLEL IMPORTS: A STRUCTURAL APPROACH APPLIED TO THE GERMAN MARKET FOR ORAL ANTI‐DIABETICS
Authors: Duso Tomaso , Herr Annika , Suppliet Moritz 
Published: August 2014

SUMMARYWe investigate the welfare impact of parallel imports using a large panel dataset containing monthly information on sales, ex‐factory prices, and further product characteristics for all 649 anti‐diabetic drugs sold in Germany between 2004 and 2010. We estimate a two‐stage nested logit model of demand, and on the basis of an oligopolistic model of multi‐product firms, we then recover the marginal costs and markups. We finally evaluate the effect of the parallel imports' policy by calculating a counterfactual scenario without parallel trade. According to our estimates, parallel imports reduce the prices for patented drugs by 11% and do not have a significant effect on prices for generic drugs. This amounts to an increase in the demand‐side surplus by €19 million per year (or €130 million in total), which is relatively small compared with the average annual market size of around €227 million based on ex‐factory prices. The variable profits for the manufacturers of original drugs from the German market are reduced by €18 million (or 37%) per year when parallel trade is allowed, yet only one third of this difference is appropriated by the importers. Copyright © 2014 John Wiley & Sons, Ltd.
PSYCHOPHYSICAL LAW AND SCALING MODELS*
Authors: Helm Carl , Messick Samuel , Tucker Ledyard 
Published: August 2014

ABSTRACTA theoretical rationale is presented for an antilog transformation in category scaling. The transformation is suggested for use in psychophysical analysis (a) to rectify the curvilinear relationships frequently found when category and ratio scaling methods are compared on the same perceptual continua, and (b) to simplify complex, artifactitious multidimensional structures.
OBJECTIVE MEASUREMENT OF PERSONALITY: CAUTIOUSNESS AND INTOLERANCE OF AMBIGUITY1
Authors: Messick Samuel , Hills John R. 
Published: August 2014

ABSTRACTObjective personality tests were developed for two aspects of intolerance of ambiguity: (a) the tendency to reach perceptual closure quickly and (b) the tendency to jump to generalizations on the basis of specific information. The two tests utilized a tab format which enabled the subject either to respond immediately to an item or to request more information, as he chose. The reliability of the personality score on one test was .91, and on the other, with only half as many items, .64. Corrected reliabilities, with various ability control measures regressed out, indicated that only a small part of this reliable variance could be accounted for by content ability. The two scores were significantly correlated (.34), and the coefficient tended to increase slightly upon partialling out various control measures. This significant correlation contributes to the construct validity of intolerance of ambiguity, but it was also pointed out that the concept of “cautiousness” presents an alternative rationale for the test procedures and is consistent with the obtained results.
USE OF TRUE‐SCORE THEORY TO PREDICT MOMENTS OF UNIVARIATE AND BIVARIATE OBSERVED SCORE DISTRIBUTIONS*
Authors: Lord Frederic M. 
Published: August 2014

ABSTRACTFormulas are derived for using the available item statistics and score statistics on a test to estimate the moments (or cumulants) of the score distribution of a lengthened (or shortened) form of the same test. Other formulas are derived for estimating the bivariate moments (or cumulants) of the scatterplot between two parallel test forms from the data available on either form alone.An empirical study is made showing in each case satisfactory agreement between the theoretical values predicted from the formulas and the values actually observed. These results suggest the utility of the true‐score model used in deriving the formulas for the estimates.