bluuebunny/crossref_metadata_2025_split huggingface dataset:
Diastereoselective Three‐Step Route to o‐(6‐Nitrocyclohex‐3‐en‐1‐yl)phenol and Tetrahydro‐6H‐benzo[c]chromen‐6‐ol Derivatives from Salicylaldehydes
Authors: Lanari Daniela , Ballini Roberto , Palmieri Alessandro , Pizzo Ferdinando , Vaccaro Luigi 
Published: April 2011

AbstractThis work was aimed at preparing o‐(6′‐nitrocyclohex‐3′‐en‐1′‐yl)phenol and tetrahydro‐6H‐benzo[c]chromen‐6‐ol derivatives in three steps starting from salicylaldehydes. Initially 3‐acetylcoumarins were prepared in the absence of solvent using a solid base catalyst such as PS‐TBD. In the second step, the Diels–Alder reactions of 3‐nitrocoumarins and 3‐acetylcoumarins under thermal conditions or in the presence of hafnium chloride yielded the corresponding tetrahydrobenzo[c]chromenones. The final part of the work was dedicated to the transformation of nitro‐tetrahydrobenzo[c]chromenones into o‐(6′‐nitrocyclohex‐3′‐en‐1′‐yl)phenol derivatives in aqueous medium and to the conversion of acetyl tetrahydrobenzo[c]chromenones into the corresponding tetrahydro‐6H‐benzo[c]chromen‐6‐ol derivatives in tetrahydrofuran (THF), in the presence of tetrabutylammonium fluoride (TBAF) on silica. In every case the diastereoselectivity was complete and the reaction yields were high.
U‐Pb zircon geochronology of granites and charnockite from southern India: implications for magmatic pulses associated with plate tectonic cycles within a Precambrian suture zone
Authors: Sato Kei , Santosh M. , Chetty T. R. K. , Hirata Takafumi 
Published: April 2011

AbstractThe Palghat–Cauvery Suture Zone (PCSZ) in southern India marks the trace along which continental blocks were sutured during the Precambrian. We report here U‐Pb geochronological data based on laser ablation ICP mass spectrometry for zircons in two granite plutons and an associated charnockite from within the PCSZ. The weighted mean of 206Pb/238U ages for a rapakivi granite from the southern part of the PCSZ yields 819 ± 26 Ma (error: 2σ; N = 13). On the other hand, a metamorphosed A‐type granite and a charnockite from the central part of the PCSZ yield a markedly older upper intercept age of 2468 ± 36 Ma (error: 2σ) and a lower intercept age of 588 ± 36 Ma (error: 2σ). Our results provide important constraints on the Precambrian crustal evolution in the PCSZ and demonstrate: (1) Neoarchaean to early Palaeoproterozoic magmatism, generating A‐type granites which we correlate with a major global crustal formation event; (2) mid Neoproterozoic magmatism, and generation of the rapakivi granite, probably associated with the subduction of the Mozambique Ocean floor; and (3) latest Neoproterozoic high‐grade metamorphism (generating the charnockite) associated with the collisional amalgamation of the Gondwana supercontinent. Together with the previous geochronological data from the PCSZ and adjacent crustal blocks, our results provide information on magmatic pulses associated with the Archaean cratonization event, as well as the Neoproterozoic Wilson Cycle of the Mozambique Ocean culminating in continent‐continent collision. Copyright © 2011 John Wiley & Sons, Ltd.
Early Precambrian mafic dyke swarms from the Central Archaean Bastar Craton, India: geochemistry, petrogenesis and tectonic implications
Authors: Srivastava Rajesh K. , Gautam Gulab C. 
Published: April 2011

AbstractThe Archaean Bastar craton is known for the presence of different generations of mafic dykes. Less studied many NW‐SE trending mafic dykes (intruded into the Archaean supracrustal rocks), encountered from the central part of the Bastar craton, are studied for their petrological and geochemical characteristics. There are many geological evidences which suggest emplacement of these mafic dykes in an intracratonic setting. Two distinct types of mafic dykes are recognized. Petrographically it is difficult to discriminate these two types. Many samples show metamorphic textures and amphibolites facies mineral assemblage but a few samples preserved original igneous texture and mineralogy. Major oxides show sub‐alkaline thoeliitic basalt/basaltic andesite nature. High‐Fe and high‐Mg contents classify them as high‐iron and high‐magnesium tholeiites. They fall in the gabbronorite field on R1‐R2 plot. Geochemical characteristics, particularly high‐field strength and rare‐earth elements, clearly distinguished them into two types: Group 1 and Group 2 mafic dykes. When compared with well‐studied mafic dyke swarms of the Southern Bastar craton, the Group 1 is recognized as Meso‐Neoarchaean sub‐alkaline mafic dykes (BD1‐CBC) and the Group 2 as Neoarchaean‐Palaeoproterozoic boninite–norite mafic dykes (BN‐CBC). The boninite–norite nature of the second group is also corroborated through immobile trace element ratios. BD1‐CBC dykes are characterized by a relatively higher concentration of HFSE and REE in comparison to BN‐CBC dykes. Some extent of crustal contamination is observed in BN‐CBC dykes but BD1‐CBC dykes do not show any indication of crustal contamination. Trace element modelling suggest that BD1‐CBC mafic dykes are derived from a melt originated through ∼20% melting of a depleted mantle source, whereas BN‐CBC mafic dykes are probably derived from a high‐Mg magma generated through ∼25% melting of a refractory mantle source. Both melts have undergone 30–40% olivine fractionation before the emplacement. Geochemistry also points out involvement of a plume in the genesis of these mafic dykes. Copyright © 2011 John Wiley & Sons, Ltd.
Laryngeal neuromonitoring and neurostimulation versus neurostimulation alone in thyroid surgery: A randomized clinical trial
Authors: Cavicchi Ottavio , Caliceti Umberto , Fernandez Ignacio Javier , Ceroni Alberto Rinaldi , Marcantoni Alessandra , Sciascia Silvia , Sottili Sandra , Piccin Ottavio 
Published: April 2011

AbstractBackgroundThe aim of this study was to assess a prospective, randomized clinical trial (RCT) comparing neurostimulation with laryngeal palpation (NSLP) of recurrent laringeal nerve (RLN) alone with NSLP associated with laryngeal neuromonitoring (LNM) to evaluate the ability of LNM in reducing the rates of RLN palsy.MethodsIn all, 250 consecutive patients scheduled to have thyroidectomy were randomized to NSLP alone (NSLP group) or NSLP with LNM (LNM group). The primary endpoint was to assess the rate of RLN palsy.ResultsThe incidence of palsy was 2.7% in the LMN group and 2.6% in the NSLP group. No significant statistical difference between the groups was observed either for permanent or for transient paralysis (respectively, Fisher's Exact test: p = 1.0 and p = 1.0).ConclusionsThis RCT shows that the use of LNM during thyroidectomy does not reduce the rates of recurrent laryngeal injuries compared with NSLP alone. [Registration number: NCT01163045 (http://www.clinicaltrials.gov).] © 2011 Wiley Periodicals, Inc. Head Neck, 2012
Extreme variability of water table dynamics in temperate calcareous fens: Implications for biodiversity
Authors: Duval Tim P. , Waddington J. M. 
Published: April 2011

AbstractCalcareous fens are minerotrophic peatlands with very high species diversity, and maintenance of the water table is assumed to be a key contributor to this diversity. However, this assumption is based on limited study of fen water table dynamics. Here we monitor water table fluctuation in distributed locations across three calcareous fens differing in hydrogeomorphic setting for three growing seasons. Water table position was extremely variable with absolute ranges of 89, > 100, and > 118 cm in the Riparian, Trough and Basin Fens, respectively, and was controlled by landscape position and weather variability. Areas adjacent to a second‐order stream experienced the least water table fluctuation, while the Basin Fen, at > 75 m from a surface water connection, was very prone to year‐to‐year precipitation differences. Mean and median water table values were found to be poor indicators of biologically relevant hydroperiods. We introduce the term ‘duration of initial growing season saturation’ as a potentially more useful statistic to relate to plant species distribution. Across the studied fens, this duration ranged from 1 to 14 weeks from the start of the growing season. The water table resided below the ground surface for between 0 and 22 weeks of the growing season across the calcareous fens and study period. These findings impart great differences in the development of oxidized rooting depths. Our results demonstrate that there is much more variation in calcareous fen hydrology than previously reported, and this variability has important implications for fen vegetation patterning and management. Copyright © 2011 John Wiley & Sons, Ltd.
Comparison of assay methods for detection of circulating tumor cells in metastatic breast cancer: AdnaGen AdnaTest BreastCancer Select/Detect™ versus Veridex CellSearch™ system
Authors: Andreopoulou E. , Yang L.‐Y. , Rangel K. M. , Reuben J. M. , Hsu L. , Krishnamurthy S. , Valero V. , Fritsche H. A. , Cristofanilli M. 
Published: April 2011

AbstractThe detection of CTCs prior to and during therapy is an independent and strong prognostic marker, and it is predictive of poor treatment outcome. A major challenge is that different technologies are available for isolation and characterization of CTCs in peripheral blood (PB). We compare the CellSearch system and AdnaTest BreastCancer Select/Detect, to evaluate the extent that these assays differ in their ability to detect CTCs in the PB of MBC patients. CTCs in 7.5 ml of PB were isolated and enumerated using the CellSearch, before new treatment. Two cutoff values of ≥2 and ≥5 CTCs/7.5 ml were used. AdnaTest requires 5 ml of PB to detect gene transcripts of tumor markers (GA733‐2, MUC‐1, and HER2) by RT‐PCR. AdnaTest was scored positive if ≥1 of the transcript PCR products for the 3 markers were detected at a concentration ≥0.15 ng/μl. A total of 55 MBC patients were enrolled. 26 (47%) patients were positive for CTCs by the CellSearch (≥2 cutoff), while 20 (36%) were positive (≥5 cutoff). AdnaTest was positive in 29 (53%) with the individual markers being positive in 18% (GA733‐2), 44% (MUC‐1), and 35% (HER2). Overall positive agreement was 73% for CTC≥2 and 69% for CTC≥5. These preliminary data suggest that the AdnaTest has equivalent sensitivity to that of the CellSearch system in detecting 2 or more CTCs. While there is concordance between these 2 methods, the AdnaTest complements the CellSearch system by improving the overall CTC detection rate and permitting the assessment of genomic markers in CTCs.
Studies on the Biosynthesis of the Stephacidin and Notoamide Natural Products: A Stereochemical and Genetic Conundrum
Authors: Sunderhaus James D. , Sherman David H. , Williams Robert M. 
Published: April 2011

AbstractThe stephacidin and notoamide natural products belong to a group of prenylated indole alkaloids containing a bicyclo[2.2.2]diazaoctane core. Biosynthetically, this bicyclic core is believed to be the product of an intermolecular Diels–Alder (IMDA) cycloaddition of an achiral azadiene. Since all of the natural products in this family have been isolated in enantiomerically pure form to date, it is believed that an elusive Diels–Alderase enzyme mediates the IMDA reaction. Adding further intrigue to this biosynthetic puzzle is the fact that several related Aspergillus fungi produce a number of metabolites with the opposite absolute configuration, implying that these fungi have evolved enantiomerically distinct Diels–Alderases. We have undertaken a program to identify every step in the biogenesis of the stephacidins and notoamides, and by combining the techniques of chemical synthesis and biochemical analysis we have been able to identify the two prenyltransferases involved in the early stages of the stephacidin and notoamide biosyntheses. This has allowed us to propose a modified biosynthesis for stephacidin A, and has brought us closer to our goal of finding evidence for, or against, the presence of a Diels–Alderase in this biosynthetic pathway.
Lessons from 35,000 feet: How ALTOUR used an open mind and an open door policy to energize the travel industry
Authors: Chemla Alexandre 
Published: April 2011

AbstractWhen a former Club Med executive decided to leave his comfortable corporate berth of ten years and dive into the waters of entrepreneurship, he chose to stay in the turbulent travel agency business, even though it was reeling from the airline industry's game‐changing deregulation. Rather than sticking with business as usual, he chose to follow an innovative business model and, subsequently, expand on it by creating ALTOUR. Sound strategy, combined with an ability to adapt to meet the needs of his customers, has led to 20 percent annual growth since the company's founding in 1991. This article explains the discipline behind this accomplishment and offers lessons that can apply across all industries. © 2011 Wiley Periodicals, Inc.
Restructuring leads to renewed competitive advantage in global financial services
Authors: Recardo Ronald J. 
Published: April 2011

AbstractWhat should an organization's leaders do when they sense that the competition is gaining on them? The answer for one strategic business unit within a global financial services company was “Restructure—and make it fast.” Within three months, the organization set up a project team that analyzed its current situation, identified and evaluated alternative designs, and designed and implemented a new structure. The results were significant improvements in revenues and customer satisfaction and a reduction in overall operating costs and key process‐cycle times. © 2011 Wiley Periodicals, Inc.
Lysozyme Coated DNA and DNA/SWNT Fibers by Solution Spinning
Authors: Nepal Dhriti , Minus Marilyn L. , Kumar Satish 
Published: April 2011

AbstractDNA fibers were prepared by solution spinning of DNA in a lysozyme (LSZ) coagulation/gelation bath. Strong positive charges carried by LSZ protein condensed the DNA (strong negative charged) molecules resulting in self‐assembly and the formation of fibrillar structures in a gel‐like network. DNA/LSZ fibril formation was found to be dependent on the ratio of DNA to LSZ. A minimum 0.1 wt.‐% of LSZ was necessary to condense 0.1 wt.‐% of DNA into micro‐fibrils. Macroscopic fiber spinning was possible by introducing a 0.1 wt.‐% DNA aqueous solution into a 0.2 wt.‐% LSZ coagulation bath which resulted in fibers with ≈20 µm diameter. Single‐walled carbon nanotubes (SWNT) were also incorporated into these fibers to explore the possibility for creating hybrid materials. All DNA‐based fibers exhibit strong birefringence confirming molecular orientation along the fiber axis. Due to the presence of LSZ, the fibers exhibit antimicrobial activity against bacteria like Micrococcus lysodeikticus.
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Externally Induced Thermal Actuation of Polymer Nanocomposites
Authors: Hu Ying , Chen Wei 
Published: April 2011

AbstractAmong the stimuli responsive polymers, thermally active polymers have attracted great attention because of the accessible and effective characteristics of thermal stimulation. Nanomaterials with their unique properties could serve as “nanoantennas” and “nanoheaters” for harvesting external energy such as electrical, optical, and magnetic, and then convert them into useful thermal energy. With a uniform mixture of the nanomaterials, an external stimulus which has no impact on the thermally responsive polymers could effectively induce the mechanical actuation of polymer nanocomposites. Hence, the trend article aims to present a brief overview of recent progress on the externally induced thermal actuation of polymer nanocomposites as well as provide a summary of the thermal actuation mechanisms. Examples are introduced to highlight the influence of embedded nanomaterials during the actuation progress. magnified image
Synthesis and Gas Permeation Properties of Spirobischromane‐Based Polymers of Intrinsic Microporosity
Authors: Fritsch Detlev , Bengtson Gisela , Carta Mariolino , McKeown Neil B. 
Published: April 2011

AbstractPolymers of intrinsic microporosity (PIMs) possess molecular structures composed of fused rings with linear units linked together by a site of contortion so that the macromolecular structure is both rigid and highly non‐linear. For PIM‐1, which has previously demonstrated encouraging gas permeability data, the site of contortion is provided by the monomer 5,5′,6,6′‐tetrahydroxy‐3,3,3′,3′‐tetramethyl‐1,1′‐spirobisindane. Here we describe the synthesis and properties of a PIM derived from the structurally related 6,6′,7,7′‐tetrahydroxy‐4,4,4′,4′‐tetramethyl‐2,2′‐spirobischromane and copolymers prepared from combination of this monomer with other PIM‐forming biscatechol monomers, including the highly rigid monomer 9,10‐dimethyl‐9,10‐ethano‐9,10‐dihydro‐2,3,6,7‐tetrahydroxyanthracene. Generally, the polymers display good solubility in organic solvents and have high average molecular masses ($\overline {M} _{{\rm w}} $) in the range 80 000–200 000 g · mol−1 and, therefore, are able to form robust, solvent‐cast films. Gas permeability and selectivity for He, H2, N2, O2, CO2, and CH4 were measured for the polymers and compared to the values previously obtained for PIM‐1. The spirobischromane‐based polymers demonstrate enhanced selectivity for a number of gas pairs but with significantly lower values for permeability. The solubility coefficient for CO2 of two of the copolymers exceed even that of PIM‐1, which previously demonstrated the highest value for a membrane‐forming polymer. Therefore, these polymers might be useful for gas or vapor separations relying on solubility selectivity.
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HPMA Based Amphiphilic Copolymers Mediate Central Nervous Effects of Domperidone
Authors: Hemmelmann Mirjam , Knoth Christiane , Schmitt Ulrich , Allmeroth Mareli , Moderegger Dorothea , Barz Matthias , Koynov Kaloian , Hiemke Christoph , Rösch Frank , Zentel Rudolf 
Published: April 2011

AbstractIn this study we give evidence that domperidone encapsulated into amphiphilic p(HPMA)‐co‐p(laurylmethacrylate) (LMA) copolymer aggregates is able to cross the blood–brain barrier, since it affected motor behaviour in animals, which is a sensitive measure for CNS actions. Carefully designed copolymers based on the clinically approved p(HPMA) were selected and synthesized by a combination of controlled radical polymerization and post‐polymerization modification. The hydrodynamic radii (Rh) of amphiphilic p(HPMA)‐co‐p(LMA) alone and loaded with domperidone were determined by fluorescence correlation spectroscopy. magnified image
Volume localized shift selective 13C spectroscopy using pulsed rotating frame transfer sequences with windows (PRAWN)
Authors: Banerjee Abhishek , Chandrakumar N. 
Published: April 2011

AbstractSome novel techniques for volume localized, chemical shift selective 13C spectroscopy are described in this work. These techniques are based on rotating frame J cross polarization and are reported for both direct and indirect modes of 13C detection. The performance of two selective mixing sequences, viz., pulsed rotating frame transfer sequences with windows (PRAWN) and PRAWN‐π has been studied systematically with different liquid and gel phantoms. Two different front‐end modules are used for volume localization, viz., point resolved spectroscopy (PRESS) and localized distortionless enhancement by polarization transfer (LODEPT). It is shown experimentally that both the selective J cross polarization sequences can operate efficiently with very low radiofrequency duty cycle; further, they have considerable tolerance to Hartmann‐Hahn mismatch. A simple theoretical analysis is also presented to understand J cross‐polarization dynamics at low RF field amplitudes. Finally, the performance of LODEPT‐PRAWN‐π is demonstrated for the selective detection of saturated fat in pigeon egg in indirect detection mode. Magn Reson Med, 2011. © 2011 Wiley Periodicals, Inc.
Net reactivity index (Δω)
Authors: Chakraborty Arindam , Das Ranjita , Giri Santanab , Chattaraj Pratim Kumar 
Published: April 2011

AbstractA Hammett‐type relationship has been obtained for a set of substituted benzoic acids, in terms of the net electrophilicity index. A new multiphilic descriptor, the net reactivity index (NRI) has been proposed. It can properly describe whether a Diels–Alder type reaction would follow a polar‐stepwise pathway or a non‐polar‐concerted mechanism. It can also clearly delineate whether a reaction is of normal or inverse electron demand type, in case the minimum ionization potential and the maximum electron affinity values do not belong to the same molecule in a diene–dienophile pair. Copyright © 2011 John Wiley & Sons, Ltd.
Elimination of Arcing in Reactive Sputtering of Al2O3 Thin Films Prepared by DC Pulse Single Magnetron
Authors: Meissner Michal , Tolg Tomas , Baroch Pavel , Musil Jindrich 
Published: April 2011

AbstractThe article reports on the elimination of arcing in the DC pulse reactive sputtering of Al2O3 thin films using a single unbalanced magnetron operating at relatively high target power density Wta ranging from ∼10 to ∼50 W/cm2; Wta is the target power density averaged over the pulse length. Correlations between pulse length τ, pulse‐off time toff, repetition frequency fr and arcing at the target surface were investigated in detail. Undesirable damage of sputtered alumina film due to arcing is demonstrated. It is shown that the length of pulse‐off time toff is of key importance for elimination of arcing in pulse reactive sputtering of electrically insulating compounds using a single magnetron. magnified image
Internal organization of large protein families: Relationship between the sequence, structure, and function‐based clustering
Authors: Cai Xiao‐Hui , Jaroszewski Lukasz , Wooley John , Godzik Adam 
Published: April 2011

AbstractThe protein universe can be organized in families that group proteins sharing common ancestry. Such families display variable levels of structural and functional divergence, from homogenous families, where all members have the same function and very similar structure, to very divergent families, where large variations in function and structure are observed. For practical purposes of structure and function prediction, it would be beneficial to identify sub‐groups of proteins with highly similar structures (iso‐structural) and/or functions (iso‐functional) within divergent protein families. We compared three algorithms in their ability to cluster large protein families and discuss whether any of these methods could reliably identify such iso‐structural or iso‐functional groups. We show that clustering using profile‐sequence and profile–profile comparison methods closely reproduces clusters based on similarities between 3D structures or clusters of proteins with similar biological functions. In contrast, the still commonly used sequence‐based methods with fixed thresholds result in vast overestimates of structural and functional diversity in protein families. As a result, these methods also overestimate the number of protein structures that have to be determined to fully characterize structural space of such families. The fact that one can build reliable models based on apparently distantly related templates is crucial for extracting maximal amount of information from new sequencing projects. Proteins 2011; © 2011 Wiley‐Liss, Inc.