bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nepethalates A and B: Two New Phthalate Derivatives from Nepeta clarkei
Authors: Hussain Javid , Rehman Najeeb Ur , Hussain Hidayat , Ali Liaqat , Al‐Harrasi Ahmed , Ahmad Viqar Uddin 
Published: November 2011

AbstractThe structure elucidation of two new phthalate derivatives named nepethalates A (1) and B (2) is reported. Both of these secondary metabolites were isolated from the MeOH extract of Nepeta clarkei. HR‐EI‐MS, IR and UV absorption spectrometry, and NMR experiments including COSY, HMQC, and HMBC were used for the determination of the structures and complete 1H‐ and 13C‐NMR assignments.
Synthesis of 2‐Aryl‐2,3‐dihydro‐3‐sulfanyl‐1H‐isoindol‐1‐ones by Pummerer‐Type Cyclization of N‐Aryl‐2‐(sulfinylmethyl)benzamides
Authors: Kobayashi Kazuhiro , Hashimoto Hiroo , Suzuki Teruhiko , Konishi Hisatoshi 
Published: November 2011

AbstractAn efficient method for the synthesis of 2‐aryl‐2,3‐dihydro‐3‐sulfanyl‐1H‐isoindol‐1‐ones 1 via Pummerer‐type cyclization of N‐aryl‐2‐(sulfinylmethyl)benzamides 2 is described. Thus, treatment of these sulfinyl‐benzamides 2, easily prepared from 2‐(bromomethyl)benzoates 3 in three steps, with Ac2O at ca. 100° resulted in the formation of the desired isoindolones 1 in generally good yields.
Improved Large‐Scale Liquid‐Phase Synthesis and High‐Temperature NMR Characterization of Short ­(F‐)PNAs
Authors: Plöger Tobias A. , von Kiedrowski Günter 
Published: November 2011

AbstractWe report on a large‐scale synthesis of F‐PNA trimer 10 and PNA trimer 11. The key improvement is the facile two‐step synthesis of (2,4‐difluoro‐5‐methylphenyl)acetic acid (2). Water solubility of the corresponding F‐PNA oligomer 10 was achieved by synthesizing solubility enhancer 5a, which is twofold positively charged and only consists of inherent structural elements of PNA. Protected and unpaired PNA n‐mers exist in a mixture of 2n conformers undergoing slow exchange and leading to complicated NMR spectra. Structure analysis was improved by recording 1H‐ and 13C‐NMR spectra at elevated temperatures above the coalescence point. Fully protected backbone derivatives show sharp resonances where expected, and spectra of protected PNAs are remarkably simplified, thereby allowing an interpretation for the first time. Both trimers 10 and 11 are considered as building blocks for a self‐replicating system based on PNA.
Modification of poly(ether urethane) with fluorinated phosphorylcholine polyurethane for improvement of the blood compatibility
Authors: Tan Dongsheng , Zhang Xiaoqing , Li Jiehua , Tan Hong , Fu Qiang 
Published: November 2011

AbstractIn order to improve the blood compatibility, poly(ether urethane) (PEU) and fluorinated phosphorylcholine polyurethane (P‐HFPC) were used to prepare PU/P‐HFPC blends by solution mixing. The hemocompatibility in vitro was evaluated with protein adsorption and platelet‐rich plasma (PRP) contact tests. It was found that the amount of adsorbed protein on surface was decreased by 87%, and almost no platelet adhesion and activation was observed on the surface of blends when P‐HFPC content was above 5 wt %. After adding P‐HFPC, the blends basically kept favorable mechanical properties of PEU though the content of P‐HFPC rises to 20 wt %. To better understand the relationship between structure and properties, the phase structure and surface property of the blend films were further investigated via differential scanning calorimetry, dynamic mechanical analysis, atomic force microscopy, X‐ray photoelectron spectroscopy, and contact angle measurements. The results indicated that the fluorinated phosphorylcholine units could be easily enriched on the surface of blend films due to the phase separation between the PEU and P‐HFPC. Therefore, ordinary poly(ether urethane)s can obtain both satisfactory blood compatibility and good mechanical properties just by blending with small amount of P‐HFPC. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2012.
Valorization of residual woody biomass (Olea europaea trimmings) based on aqueous fractionation
Authors: Requejo Ana , Peleteiro Susana , Rodríguez Alejandro , Garrote Gil , Parajó Juan Carlos 
Published: November 2011

AbstractBACKGROUND: Olive tree trimmings, a widely available agricultural residue lacking added value applications, were subjected to treatments with hot, compressed water under a variety of operational conditions. As a result of treatments, hemicelluloses were solubilized, and the treated solids were enriched in cellulose and lignin. Spent solids from autohydrolysis were assayed as substrates for enzymatic hydrolysis and for bioethanol production by simultaneous saccharification and fermentation.RESULTS: Liquors from the aqueous fractionation stage resulted in the formation of soluble hemicellulose‐derived saccharides (mainly of oligomeric nature) at yields up to 26.2 g per 100 g oven‐dry raw material. Enzymatic hydrolysis of spent solids from the aqueous fractionation step led to solutions containing up to 58.8 g glucose L−1 (corresponding to cellulose to glucose conversions up to 83.2%). Simultaneous saccharification and fermentation assays using spent solids as substrates enabled the production of media containing up to 38.2 g ethanol L−1, corresponding to 72% of the stoichiometric amount.CONCLUSION: Aqueous (or hydrothermal) processing is a technology enabling the recovery of hemicelluloses (as soluble saccharides) and the production of spent solids with high susceptibility to enzymatic hydrolysis (suitable for bioethanol production by simultaneous saccharification and fermentation). Copyright © 2011 Society of Chemical Industry
Chemical composition of ripe fruits of Rubus chamaemorus L. grown in different habitats
Authors: Jaakkola Mari , Korpelainen Ville , Hoppula Kalle , Virtanen Vesa 
Published: November 2011

AbstractBACKGROUND: Cloudberry (Rubus chamaemorus L.) is one of the most valuable berry‐producing plants because of its nutritional properties. The chemical composition and crop yield of ripe fruits of cloudberry grown wild in 10 habitats in northern Finland was analysed over two consecutive summers. For comparison, two clones of cultivated cloudberries were studied as well.RESULTS: The concentrations of citric and malic acids, α‐tocopherol, anthocyanins and β‐carotene had notable variations between habitats. In particularly, cloudberries grown on open habitats had higher content of citric acid and less α‐tocopherol compared to those grown on shaded sites. In a colder and rainy summer the content of anthocyanins and the unsaturation level of fatty acids were significantly higher than in a warmer and drier summer. Crop yields were higher in the warmer summer, except in open sites where yields were quite equal.CONCLUSION: Cloudberries grown in open habitats showed notable differences in chemical composition when compared to those grown on shaded sites. Results suggest that the amount of sunlight and temperature levels could be the main factors affecting crop yield and chemical composition of cloudberry. In addition, the amount of rainfall may have an effect on anthocyanin concentrations. Copyright © 2011 Society of Chemical Industry
HILIC‐MS/MS method development for targeted quantitation of metabolites: Practical considerations from a clinical diagnostic perspective
Authors: Rappold Brian A. , Grant Russell P. 
Published: November 2011

AbstractThe development of targeted assays for polar molecules is a persistent challenge in quantitative metabolite measurement. In addressing these challenges, hydrophilic interaction liquid chromatography (HILIC) has proved to be a valuable, though under‐used and poorly understood chromatographic technique. This work has addressed a number of components that are intrinsic in development of a high‐throughput, specific and sensitive assay for metabolites using HILIC‐MS/MS. Generally accepted HILIC doctrine, such as addition of water to all mobile phases and re‐equilibration time, was shown to be flawed under gradient HILIC mode. The effect of non‐classical mobile phase additives on HILIC‐MS/MS specificity, sensitivity and assay throughput was shown for endogenous metabolites. A broad evaluation of columns and mobile phases for the retention of varied molecular classes was performed, elucidating the empirical nature of HILIC method development. Application of the empirical evaluations performed in the paper was demonstrated by detailing a method development cycle for methylmalonic acid to achieve a highly selective and sensitive HILIC‐MS/MS quantitation capable of high‐throughput analysis for clinical utility.
Separation and purification of isorhamnetin 3‐sulphate from Flaveria bidentis (L.) Kuntze by counter‐current chromatography comparing two kinds of solvent systems
Authors: Xie Qianqian , Yin Li , Zhang Guoliang , Wei Yun 
Published: November 2011

AbstractThe first preparative separation of a flavonoid sulphate isorhamnetin 3‐sulphate from Flaveria bidentis (L.) Kuntze by counter‐current chromatography (CCC) was presented. Two kinds of solvent systems were used. A conventional organic/aqueous solvent system n‐butanol–ethyl acetate–water (4:1:5, v/v) was used, yielding isorhamnetin 3‐sulphate 2.0 mg with a purity of 93.4% from 83 mg of pre‐enriched crude extract obtained from 553 mg ethanol extract by macroporous resin. A one‐component organic/salt‐containing system composed of n‐butanol–0.25% sodium chloride aqueous solution (1:1, v/v) was also used, and the LC column packed with macroporous resin has been employed for desalination of the target compound purified from CCC. As a result, 2.1 mg of isorhamnetin 3‐sulphate with a purity of over 97% has been isolated from 402 mg of crude extract without pre‐enrichment. Compared with the conventional organic/aqueous system, the one‐component organic/salt‐containing aqueous system was more suitable for the separation of isorhamnetin 3‐sulphate, and purer target compound was obtained from the crude extract without pre‐enrichment using the new solvent system. The chemical structure was confirmed by ESI‐MS and 1H, 13C NMR. In summary, our results indicated that CCC using one‐component organic/salt‐containing aqueous solution is very promising and powerful for high‐throughput purification of isorhamnetin 3‐sulphate from Flaveria bidentis (L.) Kuntze.
Electromembrane extraction of peptides – Fundamental studies on the supported liquid membrane
Authors: Seip Knut Fredrik , Stigsson Jeanette , Gjelstad Astrid , Balchen Marte , Pedersen‐Bjergaard Stig 
Published: November 2011

AbstractA large screening of different components in the supported liquid membrane (SLM) in electromembrane extraction (EME) was performed to test the extraction efficiency on eight model peptides. Electromembrane extraction from a 500 μL acidified aqueous sample containing the model peptides in the concentration 10 μg/mL was used. Extraction time was 5 min with an electric potential of 10 V and 900 rpm agitation of the sample vial. The samples were extracted through a hollow fiber‐based SLM with different compositions of organic solvents and carriers. A small volume of acidified acceptor solution (25 μL) was after extraction analyzed directly, or with some dilution, on CE or HPLC. This article has identified mono‐ or di‐substituted phosphate groups as the prominent group of carrier molecules needed to obtain acceptable recoveries. For the organic solvents, primary alcohols and ketones have shown promise regarding recovery and reproducibility, with some differences in selectivity. A new composition of the SLM, namely 2‐octanone and tridecyl phosphate (90:10 w/w) has proved to give higher extraction recoveries and lower standard deviation than SLMs previously reported in the literature.
Determination of quinine in beverages by online coupling capillary isotachophoresis to capillary zone electrophoresis with UV spectrophotometric detection
Authors: Mikuš Peter , Maráková Katarína , Veizerová Lucia , Piešt'anský Juraj 
Published: November 2011

AbstractThe present study illustrates the possibilities of capillary isotachophoresis (CITP) online coupled with capillary zone electrophoresis (CZE) and hyphenated with fiber‐based spectrophotometric diode array detection (DAD) for the direct, highly reliable, and ultrasensitive determination of quinine (QUI) in real multicomponent ionic matrices (beverages). Here, the CITP provided an effective online sample pretreatment (preseparation and preconcentration) prior to the CZE separation. Due to the CITP sample preconcentration, a simple UV–visible absorbance spectrophotometric detection was sufficient for obtaining very low concentration limits of detection (∼2.3 ng/mL). Enhanced separation selectivity due to the combination of different separation mechanisms (CITP vs. CZE) enabled to obtain a pure analyte zone, suitable for its detection and quantitation in the directly injected real samples. The spectrophotometric DAD, unlike single wavelength UV detection, enabled to characterize the purity (i.e. spectral homogeneity) of the analyte zone and preliminary data indicate structurally related compounds via characteristic spectra recorded in the interval of 200–600 nm. The proposed CITP–CZE–DAD method was characterized by favorable performance parameters (sensitivity, linearity, precision, recovery, accuracy, robustness, and selectivity) and successfully applied to the control of QUI and potential QUI impurities in commercial beverages. This method is proposed as a routine automatized method for the highly reliable quality food control.
Determination of hydrate inhibitor in crude oil by nanoextraction–gas chromatography
Authors: Mokhtari Bahram , Pourabdollah Kobra 
Published: November 2011

AbstractThis work focused on the quantitation of methanol as a hydrate inhibitor in crude oil. The novelty is nanoextraction of a polar compound from a complex non‐polar matrix and selection of the proper fiber with maximum selectivity, loading percent, and lifetime. This approach not only does not require specific instrumentation, such as multiple columns and selective detectors, but also has eliminated the use of organic solvent and avoids the insertion of water inside the GC columns. The objective is optimization of extraction conditions, GC adjustments, and data processing. Experiments were conducted on the real sample of Iranian offshore crude oil by a carboxen/PDMS fiber via GC equipped with a cross‐linked polyethylene glycol column and flame ionization detector. The results revealed that this fiber adsorbed the alcohols among other light non‐polar compounds of crude oil. Moreover, the interference effects of ethanol were solved by proper selection of the thermal program. The LOD, LOQ, and linear range of this approach were determined to be 3.9, 12.9, and 14–229 ppm for methanol, respectively. Using the standard calibration and the standard addition methods, the relative errors of 1.6–7.2 and 5.3–14.0% were determined.
Catechol‐O‐methyltransferase Val158Met and the risk of dyskinesias in Parkinson's disease
Authors: de Lau Lonneke M.L. , Verbaan Dagmar , Marinus Johan , Heutink Peter , van Hilten Jacobus J. 
Published: November 2011

AbstractBackground:The A‐allele of the catechol‐O‐methyltransferase (COMT) Val158Met polymorphism is associated with decreased enzymatic activity and higher dopamine availability.Methods:We studied 219 patients with PD who were free of dyskinesias at baseline and underwent thorough annual examinations.Results:The A‐allele of the COMT Val158Met polymorphism was related to an increased risk of developing dyskinesias during follow‐up, in a dose‐dependent manner (adjusted hazard ratios for the AG and AA genotypes [compared to GG]: 2.09 [95% confidence interval (CI), 1.07–4.06] and 2.81 [CI, 1.43–5.54], respectively).Conclusions:This finding suggests that genetic factors may affect susceptibility to dyskinesias in PD. © 2011 Movement Disorder Society
A new radar‐based storm identification and warning technique
Authors: Li Nan , Wei Ming , Niu Ben , Mu Xiyu 
Published: November 2011

AbstractA new storm identification and warning technique is proposed which exclusively uses radar data as input. The new identification method assembles contiguous storm points to constitute 2D storm components and improve the vertical association of storm components to construct 3D storms, which can overcome the deficiencies existing in traditional identification methods. Based on the evolution properties and characteristic distributions, strong storms and general storms are specified to train support vector machines (SVMs) which then can be used to discriminate storms. The performance of the SVM shows that it can indicate the intensity and development of a storm, providing an important aid in severe weather warning. Copyright © 2011 Royal Meteorological Society
Accelerated phase‐contrast cine MRI using k‐t SPARSE‐SENSE
Authors: Kim Daniel , Dyvorne Hadrien A. , Otazo Ricardo , Feng Li , Sodickson Daniel K. , Lee Vivian S. 
Published: November 2011

AbstractPhase‐contrast (PC) cine MRI is a promising method for assessment of pathologic hemodynamics, including cardiovascular and hepatoportal vascular dynamics, but its low data acquisition efficiency limits the achievable spatial and temporal resolutions within clinically acceptable breath‐hold durations. We propose to accelerate PC cine MRI using an approach which combines compressed sensing and parallel imaging (k‐t SPARSE‐SENSE). We validated the proposed 6‐fold accelerated PC cine MRI against 3‐fold accelerated PC cine MRI with parallel imaging (generalized autocalibrating partially parallel acquisitions). With the programmable flow pump, we simulated a time varying waveform emulating hepatic blood flow. Normalized root mean square error between two sets of velocity measurements was 2.59%. In multiple blood vessels of 12 control subjects, two sets of mean velocity measurements were in good agreement (mean difference = −0.29 cm/s; lower and upper 95% limits of agreement = −5.26 and 4.67 cm/s, respectively). The mean phase noise, defined as the standard deviation of the phase in a homogeneous stationary region, was significantly lower for k‐t SPARSE‐SENSE than for generalized autocalibrating partially parallel acquisitions (0.05 ± 0.01 vs. 0.19 ± 0.06 radians, respectively; P < 0.01). The proposed 6‐fold accelerated PC cine MRI pulse sequence with k‐t SPARSE‐SENSE is a promising investigational method for rapid velocity measurement with relatively high spatial (1.7 mm × 1.7 mm) and temporal (∼35 ms) resolutions. Magn Reson Med, 2011. © 2011 Wiley Periodicals, Inc.
Ultrahigh field systems and applications at 7 T and beyond: Progress, pitfalls, and potential
Authors: Bandettini Peter A. , Bowtell Richard , Jezzard Peter , Turner Robert 
Published: November 2011

AbstractAbout 150 researchers around the world convened at the Chateau Lake Louise on February 20–23, 2011 to present and discuss the latest research in human and animal imaging and spectroscopy at field strengths of 7 T or above (termed ultrahigh field) at the third ISMRM‐sponsored high field workshop. The clear overall message from the workshop presentations and discussion is that ultrahigh field imaging is gaining momentum with regard to new clinically relevant findings, anatomic and functional MRI results, susceptibility contrast advancements, solutions to high field‐related image quality challenges, and to generally push the limits of resolution and speed of high field imaging. This meeting report is organized in a manner reflecting the meeting organization itself, covering the seven sessions that were approximately titled: (1) high field overview from head to body to spectroscopy; (2) susceptibility imaging; (3) proffered session on susceptibility, ultrafast imaging, unique contrast at 7 T, and angiography; (4) neuroscience applications; (5) proffered session on coils, shimming, parallel imaging, diffusion tensor imaging, and MRI‐PET fusion; (6) high field animal imaging and spectroscopy, as well as a vendor overview, and (7) Cutting edge technology at 7 T. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
The effect of an educational intervention on meperidine use in Nova Scotia, Canada: a time series analysis
Authors: Fisher Judith E. , Zhang Ying , Sketris Ingrid , Johnston Grace , Burge Fred 
Published: November 2011

ABSTRACTPurposeTo evaluate the impact of a prescriber focused individual educational and audit–feedback intervention undertaken by the Nova Scotia Prescription Monitoring Program (NSPMP) in March/April 2007 to reduce meperidine use.MethodThe NSPMP records all prescriptions for controlled substances dispensed in community pharmacies in Nova Scotia, Canada. Oral meperidine use from 1 July 2005 to 31 December 2009 was examined using NSPMP data. Monthly totals for the following were obtained: number of individual patients who filled at least one meperidine prescription, number of prescriptions, and number of tablets dispensed. Data were analyzed graphically to observe overall trends. The intervention effect was estimated on the logarithmic scale with autocorrelations over time modeled by an integrated autoregressive moving average model for each outcome measure.ResultsAn overall trend toward decreasing use from July 2005 to December 2009 was apparent for all three outcome measures. The intervention was associated with a statistically significant reduction in meperidine use, after adjusting for the overall long‐term trend. Compared with the pre‐intervention period, the monthly number of patients declined by 12% (p < 0.001; 95% confidence interval [CI] = 5%–18%), prescriptions by 10% (p < 0.001; 95%CI = 3%–17%), and tablets by 13.5% (p < 0.001, 95%CI = 6%–29%) in the post‐intervention period.ConclusionGiven the risks associated with meperidine, determining that this intervention successfully reduced meperidine use is encouraging. This study highlights the potential for using population data such as the NSPMP to evaluate the effectiveness of population‐level interventions to improve medication use, including professional, organizational, financial, and regulatory initiatives. Copyright © 2011 John Wiley & Sons, Ltd.
Formation of poly(octadecyl acrylate) brushes on a silicon wafer surface
Authors: Öztürk Esra , Turan Eylem , Caykara Tuncer 
Published: November 2011

AbstractTo introduce an ultrahydrophobic polymeric phase onto a silicon wafer, an initiator‐modified silicon wafer was prepared with 2‐bromopropionyl bromide and then surface‐initiated atom transfer radical polymerization of octadecyl acrylate was carried out from the initiator‐grafted silicon wafer using CuBr and N,N,N′,N″‐pentamethyldiethylenetriamine as catalyst precursors. The resultant poly(octadecyl acrylate) [poly(ODA)] brushes were characterized by ellipsometry, X‐ray photoelectron spectroscopy, grazing angle Fourier transform infrared spectroscopy, atomic force microscopy, gel permeation chromatography and water contact angle measurements. Wettability of the poly(ODA) brushes was found to depend on the surface coverage (Γ) and the root mean square roughness. The most hydrophobic surface (Γ = 25.35 mg m−2 and root mean square roughness 11.9 nm) exhibited a water contact angle of 171.1 ± 0.2°. Copyright © 2011 Society of Chemical Industry