bluuebunny/crossref_metadata_2025_split huggingface dataset:
Anticancer and Toxic Properties of Cyclotides are Dependent on Phosphatidylethanolamine Phospholipid Targeting
Authors: Troeira Henriques Sónia , Huang Yen‐Hua , Chaousis Stephanie , Wang Conan K. , Craik David J. 
Published: August 2014

AbstractCyclotides, ultrastable disulfide‐rich cyclic peptides, can be engineered to bind and inhibit specific cancer targets. In addition, some cyclotides are toxic to cancer cells, though not much is known about their mechanisms of action. Here we delineated the potential mode of action of cyclotides towards cancer cells. A novel set of analogues of kalata B1 (the prototypic cyclotide) and kalata B2 and cycloviolacin O2 were examined for their membrane‐binding affinity and selectivity towards cancer cells. By using solution‐state NMR, surface plasmon resonance, flow cytometry and bioassays we show that cyclotides are toxic against cancer and non‐cancerous cells and their toxicity correlates with their ability to target and disrupt lipid bilayers that contain phosphatidylethanolamine phospholipids. Our results suggest that the potential of cyclotides as anticancer therapeutics might best be realised by combining their amenability to epitope engineering with their ability to bind cancer cell membranes.
A Robust Nanoporous Supramolecular Metal–Organic Framework Based on Ionic Hydrogen Bonds
Authors: Roques Nans , Mouchaham Georges , Duhayon Carine , Brandès Stéphane , Tachon Aurélie , Weber Guy , Bellat Jean Pierre , Sutter Jean‐Pascal 
Published: August 2014

AbstractHydrogen‐bond assembly of tripod‐like organic cations [H3‐MeTrip]3+ (1,2,3‐tri(4′‐pyridinium‐oxyl)‐2‐methylpropane) and the hexa‐anionic complex [Zr2(oxalate)7]6− leads to a structurally, thermally, and chemically robust porous 3D supramolecular framework showing channels of 1 nm in width. Permanent porosity has been ascertained by analyzing the material at the single‐crystal level during a sorption cycle. The framework crystal structure was found to remain the same for the native compound, its activated phase, and after guest resorption. The channels exhibit affinities for polar organic molecules ranging from simple alcohols to aniline. Halogenated molecules and I2 are also taken up from hexane solutions by this unique supramolecular framework.
From Covalent Glycosidase Inhibitors to Activity‐Based Glycosidase Probes
Authors: Willems Lianne I. , Jiang Jianbing , Li Kah‐Yee , Witte Martin D. , Kallemeijn Wouter W. , Beenakker Thomas J. N. , Schröder Sybrin P. , Aerts Johannes M. F. G. , van der Marel Gijsbert A. , Codée Jeroen D. C. , Overkleeft Hermen S. 
Published: August 2014

AbstractActivity‐based protein profiling has emerged as a powerful discovery tool in chemical biology and medicinal chemistry research. Success of activity‐based protein profiling hinges on the presence of compounds that can covalently and irreversibly bind to enzymes, do so selectively in the context of complex biological samples, and subsequently report on the selected pool of proteins. Such tagged molecules featuring an electrophilic trap, termed activity‐based probes, have been developed with most success for serine hydrolases and various protease families (serine proteases, cysteine proteases, proteasomes). This concept presents the current progress and future directions in the design of activity‐based probes targeting retaining glycosidases, enzymes that employ a double displacement mechanism in the hydrolysis of glycosidic bonds with overall retention. In contrast to inverting glycosidases, retaining glycosidases form a covalent intermediate with their substrates during the catalytic process and are therefore amenable to activity‐based protein profiling studies.
Improvement of Magnesia Refractory Ceramics for Applications in Gasifiers
Authors: Gerlach Nora , Gehre Patrick , Aneziris Christos G. 
Published: August 2014

AbstractIn Vergasungsanlagen erfolgt die Umsetzung von kohlenstoffhaltigen Rohstoffen unter Zugabe von Sauerstoff und Wasserdampf zu Synthesegas. Durch die Entwicklung neuer Verfahrensweisen konnte die Maximaltemperatur gesenkt werden. Dies ermöglicht den Ersatz der hochchromoxidhaltigen feuerfesten Auskleidung durch kostengünstigere und umweltfreundlichere Werkstoffe. Hier wurden die mechanischen und chemischen Eigenschaften von ZrO2‐dotierten Magnesiumoxid‐Feuerfestkeramiken untersucht und hinsichtlich der Eignung als Auskleidungsmaterial in Vergasungsanlagen bewertet.
CO2 – Baustein des Lebens und Treiber der globalen Erwärmung
Authors: Riener Korbinian , Kühn Fritz E. 
Published: August 2014

AbstractSeit hunderten von Millionen Jahren nutzt die Natur Kohlendioxid in der Photosynthese als Baustein des Lebens. Die gasförmige Verbindung ist zudem von essentieller Bedeutung im Kohlenstoffkreislauf und für den Transport von Kohlenstoff zwischen den Erdsphären mitverantwortlich. In den letzten Jahren ist CO2 vermehrt in Zusammenhang mit der globalen Erderwärmung in den Fokus gerückt, da die Verbrennung primär fossiler Rohstoffe seit Beginn der Industrialisierung zu einem erheblichen Anstieg der CO2‐Konzentration in der Atmosphäre geführt hat. Eine Reduktion des Ausstoßes wird nun im globalen Kontext angestrebt und aufgrund der Verknappung fossiler Rohstoffe ist auch ein Trend Richtung erneuerbarer Ressourcen klar zu erkennen. Hier kann die Nutzung von nahezu unbegrenzt vorhandenem CO2 durch die chemische Industrie ihren Beitrag leisten.
Trends in den Polymerwissenschaften
Authors: Nuyken Oskar 
Published: August 2014

AbstractMit diesem Beitrag soll gezeigt werden, dass der Phantasie des Polymerchemikers kaum Grenzen gesetzt sind. Zur Verwirklichung der gestellten Aufgabe bedient er sich Erkenntnissen aus allen Bereichen der Chemie, der Verfahrenstechnik, Biologie und anderer Naturwissenschaften. Die hier vorgestellten Probleme und Lösungsansätze sind vor allem Herausforderungen an den Synthese‐, den Physiko‐ und den technischen Chemiker. Der Einbau von –N=N‐Funktionen in die Hüllwand von Mikrokapseln macht diese thermolabil und für den Thermotransferdruck einsetzbar. Durch verwandte Funktionen wie –N=N–NR– oder –N=N–P(O)(OR)2– in der Hauptkette von Polymeren werden diese besonders photolabil und können daher mittels Laser fragmentiert und damit strukturiert werden. Für OLEDs wurden Polymere wegen ihrer “Unreinheit” anfangs als ungeeignet eingestuft. Dank vieler Fortschritte bei der Synthese und vieler unübersehbarer Vorteile der Polymere gegenüber niedermolekularen Verbindungen werden diese auch im Bereich der OLEDs zunehmend eine wichtige Rolle spielen. Mit dem Beitrag über den “Spinning Disk Reactor” soll für eine Technologie geworben werden, die m. E. in ihren Möglichkeiten noch völlig unterschätzt wird.
Biogene Polymere als Template
Authors: Zollfrank Cordt 
Published: August 2014

AbstractEs wird das Potential von biologischen Templaten für die bioinspirierte Synthese anorganischer Materialien und Werkstoffe vorgestellt. Es konnte gezeigt werden, dass Polysaccharide geeignete Basisstrukturen für die Generierung unterschiedlichster anorganischer Materialien sind. Insbesondere Cellulose ist besonders gut als Strukturtemplat geeignet. Mikroorganismen wie Bakterien oder Algen können ebenfalls als Template eingesetzt werden, da diese vielfach Cellulose und andere Polysaccharide sekretieren. Die Nutzung des hohen Potentials des bioinspirierten Materialdesigns, erfordert dabei das fächerübergreifende Zusammenspiel von Ingenieuren, Chemikern, Physikern und Biologen.
Wie unsere Nase die enantiomeren Linaloole unterscheidet
Authors: Prasse Agneta , Siehl Hans‐Ullrich , Zeller Klaus‐Peter , Berger Stefan , Sicker Dieter 
Published: August 2014

AbstractDie beiden enantiomeren Formen des Linalools wurden aus Rosenholzöl bzw. Korianderöl durch Vakuumdestillation isoliert und anschließend mittels Säulenchromatographie gereinigt. Alle analytischen Spektren sind vollständig entweder im Hauptteil oder in der supporting information wiedergegeben. Die NMR‐ sowie die Massenspektren werden eingehend interpretiert und mit theoretischen Berechnungen der 13C‐chemischen Verschiebungen verglichen. Das Projekt stellt eine Fortsetzung des Buches “Classics in Spectroscopy” von S. Berger und D. Sicker (Wiley‐VCH 2009) dar.
Linoleum
Authors: Hübner Karl 
Published: August 2014

AbstractVor 150 Jahren begann die industrielle Produktion von Linoleum. Noch bevor die ersten Kunststoffe auf Erdölbasis entstanden, kam damit ein künstlich hergestelltes Polymer zum Einsatz. Nach einer großen Zeit in den ersten Jahrzehnten des 20. Jahrhunderts spielt Linoleum heute trotz seiner Nachhaltigkeit nur noch in Nischenmärkten eine Rolle. Immerhin: Ein deutscher Produktionsstandort hat den Niedergang überlebt. Die Anfänge des Materials lagen jedoch in England.
National Breast and Cervical Cancer Early Detection Program data validation project
Authors: Eheman Christie R. , Leadbetter Steven , Benard Vicki B. , Blythe Ryerson A. , Royalty Janet E. , Blackman Donald , Pollack Lori A. , Adams Paula Willey , Babcock Fran 
Published: August 2014

BACKGROUNDThe objectives of this study were to evaluate the quality of national data generated by the National Breast and Cervical Cancer Early Detection Program (NBCCEDP); to assess variables collected through the program that are appropriate to use for program management, evaluation, and data analysis; and to identify potential data‐quality issues.METHODSInformation was abstracted randomly from 5603 medical records selected from 6 NBCCEDP‐funded state programs, and 76 categorical variables and 11 text‐based breast and cervical cancer screening and diagnostic variables were collected. Concordance was estimated between abstracted data and the data collected by the NBCCEDP. Overall and outcome‐specific concordance was calculated for each of the key variables. Four screening performance measures also were estimated by comparing the program data with the abstracted data.RESULTSBasic measures of program outcomes, such as the percentage of women with cancer or with abnormal screening tests, had a high concordance rate. Variables with poor or inconsistent concordance included reported breast symptoms, receipt of fine‐needle aspiration, and receipt of colposcopy with biopsy.CONCLUSIONSThe overall conclusion from this comprehensive validation project of the NBCCEDP is that, with few exceptions, the data collected from individual program sites and reported to the CDC are valid and consistent with sociodemographic and clinical data within medical records. Cancer 2014;120(16 suppl):2597‐603. © 2014 American Cancer Society.
Microwave‐Assisted C–C and C–S Couplings Catalysed by Organometallic Pd‐SCS or Coordination Ni‐SNS Pincer Complexes
Authors: Basauri‐Molina Manuel , Hernández‐Ortega Simón , Morales‐Morales David 
Published: August 2014

AbstractA family of SCS and SNS pincer compounds of the type [PdCl{C6H3‐2,6‐(CH2SR)2}] {R = tBu (3a), sBu (3b), iBu (3c)} and [NiCl2{C5H3N‐2,6‐(CH2SR)2}] {R = tBu (4a), sBu (4b)} have been prepared. Among these, complexes 3b, 3c, 4a–4c are reported for the first time. Dimeric compounds such as [NiCl{C5H3N‐2,6‐(CH2SiBu)2}μ‐Cl]2 (4c) were found in the solid state for the nickel complexes with lower steric hindrance exhibiting octahedral metal centers, whereas other nickel structures such as [NiCl2{C5H3N‐2,6‐(CH2StBu)2}(iPrOH)] (4d) could also expand their coordination number by coordinating to solvents. The single crystal X‐ray diffraction results for 4a, 4c and 4d are presented. The catalytic activity of the six compounds was studied in C–C and C–S cross‐coupling reactions under conventional heating and under microwave irradiation conditions. The palladium catalysts enabled good to excellent conversions in Suzuki–Miyaura couplings of p‐substituted halobenzenes with phenylboronic acid. Comparable yields resulted from application of the nickel complexes in the thioetherification of iodobenzene with different disulfides. The fast increase in reaction temperature associated with microwave irradiation, in combination with the robust pincer catalysts, allowed for quantitative conversions in only minutes.
(Arene)ruthenium Complexes with Imidazolin‐2‐imine and Imidazolidin‐2‐imine Ligands
Authors: Tönnemann Justus , Scopelliti Rosario , Severin Kay 
Published: August 2014

AbstractImidazolin‐2‐imine and imidazolidin‐2‐imine ligands are versatile N donors in transition metal chemistry. Here, we describe the synthesis and characterization of (arene)Ru complexes with these ligands. Simple adducts of the type [(p‐cymene)Ru(L)Cl2] (L = 1,3‐diarylimidazolin‐2‐imine or 1,3‐dimesitylimidalzolidin‐2‐imine) can be converted into complexes in which the imines act as π ligands with tethered imine groups. Furthermore, the high basicity of the N donor group can promote self‐activation of the (arene)Ru complexes.
A single‐sample method to determine the hydroxyl values of polyols using mid‐FTIR spectroscopy
Authors: Tavassoli‐Kafrani Mohammad Hossein , Curtis Jonathan M. , van de Voort Frederik R. 
Published: August 2014

A single‐sample Fourier transform infrared (FTIR) method suitable for automation was developed to determine the hydroxyl value (OHV) of lipid‐based polyols. It is a modification of the original split‐sample FTIR method using the reaction of p‐toluenesulfonyl isocyanate (TSI) with OH groups and measures the carbamate band formed in the differential spectrum before and after the reaction. In the new method, the TSI‐isocyanate absorption is measured before and after the reaction, the area change being proportional to the OHV of the sample, but is sensitive to moisture. Moisture compensation is achieved by monitoring the CO2 produced by the water‐TSI reaction and correcting for its additional contribution to isocyanate loss. The method was validated by assessing polyol mixtures containing added water, comparing the results to those from the moisture independent split‐sample FTIR method. The single‐sample FTIR procedure had similar accuracy and reproducibility as the split‐sample method when CO2 moisture compensation was implemented. The procedure was not affected by carboxylic acids but can be affected by the presence of amines. The advantage of the new OHV FTIR method is that it requires only a single sample to be prepared and analyzed, making it amenable to automation as well as reducing sample preparation time, solvent, and reagent use.Practical applications: This paper provides an automatable, rapid, and accurate FTIR‐based method for determination of hydroxyl value of polyols, which is a critical parameter of polyols and polyurethane production. The method can be employed by commercial laboratories and researchers working in this area for quality control and to facilitate improvement and development of new products.An FTIR method is described to measure hydroxyl values of polyols using the reaction with isocyanate employed in other methods. The new approach is suitable for automation and moisture compensation is achieved in the same experiment by measuring CO2 produced. Method validation indicates that the method is accurate compared to theoretical values.
Diversity‐Oriented Synthesis of Polycyclic Indoles: Brønsted or Lewis Acid Catalyzed Three‐Component Reaction for the Synthesis of α‐Carbolines and Pyrimidoindoles
Authors: Arigela Rajesh K. , Kumar Ravi , Samala Srinivas , Gupta Sahaj , Kundu Bijoy 
Published: August 2014

AbstractWe report the diversity‐oriented synthesis of pyrido‐ and pyrimido‐indoles from an acid‐catalyzed three component (3C) reaction involving ethyl 2‐amino‐1H‐indole‐3‐carboxylates, arylaldehydes, and terminal alkynes. In the presence of a Brønsted acid such as trifluoroacetic acid (TFA), the 3C reaction furnished a mixture of pyrido‐ and pyrimido‐indoles, whereas when catalyzed by Yb(OTf)3 as a Lewis acid, pyrimidoindoles were obtained as the single product. The findings demonstrate the ability to control reaction products through change in the acid catalyst. The salient feature during TFA‐catalyzed 3C reaction is that two different pathways are followed in one pot after propargylamine formation. The two cascade cyclizations comprise in situ decarboxylation‐carbocyclization and an intramolecular hydroamination to afford products with different connectivity.
Polysomnography: Assessment of decannulation readiness in chronic upper airway obstruction
Authors: Wolter Nikolaus E. , Anderson Jennifer 
Published: August 2014

Objectives/HypothesisTo evaluate the clinical value of polysomnography in patients with a tracheotomy due to chronic upper airway obstruction prior to attempting decannulation.Study DesignRetrospective chart review.MethodsSubjects with chronic upper airway obstruction were identified using a clinical database between 2000 and 2014. All subjects had a tracheotomy, were assessed by the senior author in a tertiary care academic center, and underwent polysomnography prior to attempting decannulation. Patients were excluded if they did not undergo polysomnography or had severe obstructive sleep apnea as the primary indication for tracheotomy.ResultsFifteen patients were identified. The majority (87.5%) of patients were successfully decannulated after their first polysomnography showed acceptable results when carried out with the tracheotomy occluded. Obstructive sleep apnea was identified in four of the nine patients who tolerated overnight tracheotomy occlusion, and continuous positive airway pressure (CPAP) was initiated. An additional four of the remaining six patients were decannulated after subsequent polysomnography demonstrated improvement with CPAP, and two required an additional airway procedure.ConclusionsChronic upper airway obstruction requiring tracheotomy can be challenging to treat and successfully decannulate. Indirect laryngoscopy is essential to evaluate the anatomy of the larynx; however, it cannot assess potential increased obstruction during sleep. The study indicates that polysomnography can assist with the evaluation of decannulation readiness in patients with chronic upper airway obstruction as an adjunct measure in addition to imaging and laryngoscopy.Level of Evidence4 Laryngoscope, 124:2574–2578, 2014
Comparison of tensile strength of fibrin glue and suture in microflap closure
Authors: Myer Charles M. , Johnson Christopher M. , Postma Gregory N. , Weinberger Paul M. 
Published: August 2014

Objectives/HypothesisSuture closure and fibrin glue placement have been advocated as alternatives to healing by secondary intention. The aim of this study was to examine the tensile strength of these microflap closure techniques.Study DesignBasic research.MethodsThree pairs of excised bovine true vocal folds underwent microflap creation and closure by either single 6‐0 polyglactin suture or fibrin glue. Vocal folds were distracted to failure on a universal testing system. Excised porcine true vocal folds underwent microflap creation and were closed with either single 6‐0 polyglactin suture or fibrin glue, or were left without closure. Tensile strength testing was performed with a universal testing system measuring load at 1 mm, 5 mm, and 10 mm of distraction.ResultsThe bovine vocal fold model failed after an average extension of 22.6 mm (range, 21.4–23.9 mm) corresponding to 11.61 N (range, 8.04–13.47 N), with no failure of the suture prior to model failure. Fibrin glue did not demonstrate any measureable resistance to tension application. In the porcine vocal fold model, there was a significant difference between the median tensile load of suture closure (2.91 N) and no closure (1.16 N) at 10 mm of distraction (P = .01). There was no significant difference in median load of vocal folds undergoing fibrin glue closure or no closure.ConclusionsThere is no significant difference in tensile strength of a microflap closed with fibrin glue or not closed. Suture closure of a microflap provides a significantly stronger mechanical closure than no closure. This suggests that use of fibrin glue is of little benefit on the vocal folds.Level of EvidenceNA Laryngoscope, 125:167–170, 2015
Stability and optimality of decay rate for a weakly dissipative Bresse system
Authors: Alves M.O. , Fatori L.H. , Jorge Silva M.A. , Monteiro R.N. 
Published: August 2014

AbstractThis paper is concerned with asymptotic stability of a Bresse system with two frictional dissipations. Under mathematical condition of equal speed of wave propagation, we prove that the system is exponentially stable. Otherwise, we show that Bresse system is not exponentially stable. Then, in the latter case, by using a recent result in linear operator theory, we prove the solution decays polynomially to zero with optimal decay rate. Better rates of polynomial decay depending on the regularity of initial data are also achieved. Copyright © 2014 John Wiley & Sons, Ltd.
Model order reduction for meshfree solution of Poisson singularity problems
Authors: Chen Jiun‐Shyan , Marodon Camille , Hu Hsin‐Yun 
Published: August 2014

SummaryModel order reduction (MOR) techniques for enriched reproducing kernel meshfree methods are proposed for analysis of Poisson problems with mild and strong singularities. The employment of an integrated singular basis function method (ISBFM), in conjunction with the selection of harmonic near‐tip asymptotic basis functions, leads to a Galerkin formulation in which the non‐smooth near‐tip basis functions appear only on the boundaries away from the singularity point. This approach avoids the need of integrating the derivatives of non‐smooth functions near the singularity point and yields a discrete system that allows effective MOR procedures. Under this framework, a decomposed reduction method equipped with two distinct projections for smooth and non‐smooth parts of the finite‐dimensional space is proposed. Compared with the uniform reduction approach using a single projection operator, the decomposed projection on ISBFM discrete system preserves the singularity behavior of the fine‐scale solution in its lower‐dimensional approximation. Analytical error estimation and stability analysis show that ISBFM with the decomposed projection can achieve better accuracy with only a slight increase of condition number compared with the uniform reduction approach in the reduced‐order solution of singularity problems. The numerical tests validate the effectiveness of the proposed methods. Copyright © 2014 John Wiley & Sons, Ltd.
ASSESSING THE IMPACT OF REGULATORY REFORM IN DEVELOPING COUNTRIES
Authors: Kirkpatrick Colin 
Published: August 2014

SUMMARYEffective economic governance is a key condition for economic growth and development, and donor support to developing countries has increasingly been focused on regulatory reforms that are intended to enable markets to function more efficiently thereby providing a stable and supportive environment for investment, private sector development, and market‐led economic growth. This article reviews the empirical evidence on the impact of regulatory reform in developing countries. The evidence is broadly consistent with a priori expectations, showing a positive relationship between regulatory reform and improved economic performance. However, various methodological and data problems weaken the robustness of these findings and point to the need to broaden the range of designs and methods for evaluating the results of donor‐supported regulatory reforms in developing countries. © 2014 The Authors. Public Administration and Development published by John Wiley & Sons, Ltd.