bluuebunny/crossref_metadata_2025_split huggingface dataset:
Essential Oil of Indian Propolis: Chemical Composition and Repellency against the Honeybee Apis florea
Authors: Naik Dattatraya G. , Vaidya Harshada S. , Namjoshi Tejas P. 
Published: April 2013

AbstractHitherto unknown biological properties and the chemical composition of the essential oil isolated from propolis of Indian origin were established. GC/MS Analysis of the essential oil revealed the presence of 32 constituents, of which ten were major compounds, nine had intermediate contents, and 13 were minor compounds. With the exception of six minor constituents, that could not be identified, their identification was based on the comparison of their mass spectra and Kovats retention indices with those listed in the NIST and Wiley mass spectral libraries. Their structural assignment was confirmed by GC/MS co‐injection of the essential oil with authentic compounds. Quantification of the components was done by GC‐FID analyses. Moreover, the essential oil was shown to possess repellent activity against the honeybee Apis florea. The activity was found to be dose dependent. The average repellency (ΔR) increased with increasing essential‐oil concentration up to 24 μg/ml and remained constant for the formulation with the higher concentration. These findings established the chemical constitution of the essential oil and might be useful to beekeepers for the improvement of the bee management.
Essential Oils from the Roots of Echinops bannaticusRochel ex Schrad. and Echinops sphaerocephalus L. (Asteraceae): Chemotaxonomic and Biosynthetic Aspects
Authors: Radulović Niko S. , Denić Marija S. 
Published: April 2013

AbstractHerein, we report, for the first time, the results of detailed chemical and statistical analyses of the essential oils from the roots of two Echinops species (Asteraceae), E. bannaticus Rochel ex Schrad., and E. sphaerocephalus L., from the weed flora of Serbia. Among 106 and 81 constituents, respectively, S‐containing polyacetylene compounds and triquinane sesquiterpenoids made up ca. 80% of the oils. Several of these compounds are reported here as new metabolites for the two species or even for the genus Echinops. A multivariate statistical comparison of the essential‐oil composition data for these two and additional six taxa of this genus available from the literature permitted an examination of the mutual relationships of the taxa within this morphologically highly uniform genus. Principal component analysis (PCA) and agglomerative hierarchical clustering revealed a grouping of E. bannaticus and E. sphaerocephalus (both belonging to the section Echinops), and their close relationship with E. grijsii, suggesting a circumscription of this Chinese taxon to the section Echinops. PCA Correlation matrix offered valuable insight into the biosynthetic links between essential‐oil constituents, and these agreed excellently with the currently proposed ones for the polyacetylene S‐containing compounds, triquinanes, and monoterpenes.
Endovascular treatment of type B dissection in patients with marfan syndrome: Mid‐term outcomes and aortic remodeling
Authors: Eid‐Lidt Guering , Gaspar Jorge , Meléndez‐Ramírez Gabriela , Cervantes S. Jorge , González‐Pacheco Hector , Dámas de Los Santos Félix , Meave‐González Aloha , Ramírez Marroquín Samuel 
Published: April 2013

ObjectivesTo evaluate the mid‐term outcomes, and the aortic remodeling in Marfan syndrome (MFS) patients with type B dissection that were treated with endovascular repair.BackgroundMFS is a relative contraindication to thoracic endovascular aortic repair (TEVAR). Mid‐term aortic outcomes data in MFS after TEVAR are limited, and the occurrence of late events remains unclear.MethodsOf 89 patients that underwent TEVAR between September 2002 and February 2011, 10 patients with mid‐term follow‐up fulfilled the Ghent criteria for MFS and complicated type B dissection. High risk for open surgery was documented in 90%.ResultsThe mean age was 35.1 ± 9.4 years and all patients presented with acute aortic syndrome complicating a chronic type B dissection (DeBakey type IIIb). Five patients underwent a Bentall surgical procedure previous to endovascular repair, and in four patients initial TEVAR was followed by surgery of the ascending aorta. Treatment was limited to endovascular repair in only one patient. In‐hospital mortality was 10%. At a mean follow‐up of 59.6 ± 38.9 months, the cumulated mortality was of 20% and late mortality 11.1%. The rate of secondary endoleak was 44.4%, and late reintervention of 33.3%. Survival freedom from cardiovascular death at 8 years was 80.0%, and positive remodeling was documented in 37.5% of patients.ConclusionsOur results suggest that TEVAR is feasible, safe, and associated with a high reintervention rate and reduced rate of positive aortic remodeling in patients with Marfan syndrome. Survival at 8 years was comparable to contemporary series of open repair. © 2012 Wiley Periodicals, Inc.
Encapsulation of an Olefin Metathesis Catalyst in the Nanocages of SBA‐1: Facile Preparation, High Encapsulation Efficiency, and High Activity
Authors: Yang Hengquan , Ma Zhancheng , Zhou Ting , Zhang Wenjuan , Chao Jianbin , Qin Yong 
Published: April 2013

AbstractBy postreducing the window size through silylation, 2nd generation Hoveyda–Grubbs catalyst was encapsulated in the nanocages of a mesoporous material SBA‐1. The encapsulation efficiency of SBA‐1 was up to 70 %, much higher than that of other mesoporous materials such as SBA‐16, FDU‐12, and MCM‐41 (0–43 %). The successful encapsulation was confirmed by N2 sorption analysis and FTIR and diffusion reflectance UV/Vis spectroscopy. Such a SBA‐1‐encapsulated catalyst showed good activity in both olefin ring‐closing metathesis and cross metathesis. A wide range of olefins could be transformed to the desired products with conversions of 27–100 %. The encapsulated catalyst showed more sensitive temperature effects than the homogeneous counterpart, reflecting the unique properties of the encapsulated catalyst. At reaction temperatures of 40–60 °C, the activity of the encapsulated catalyst was sufficiently comparable to that of the homogeneous catalyst for the cross metathesis of styrene‐type substrates, probably because of the confinement effects of the nanocages. The solid catalyst could be recycled seven times. This study not only supplies a new solid catalyst for olefin metathesis but also demonstrates our improvement in immobilizing metal complex catalyst toward a green and effective level.
Protein‐Directed Synthesis of Mn‐Doped ZnS Quantum Dots: A Dual‐Channel Biosensor for Two Proteins
Authors: Wu Peng , Zhao Ting , Tian Yunfei , Wu Lan , Hou Xiandeng 
Published: April 2013

AbstractProteins typically have nanoscale dimensions and multiple binding sites with inorganic ions, which facilitates the templated synthesis of nanoparticles to yield nanoparticle–protein hybrids with tailored functionality, water solubility, and tunable frameworks with well‐defined structure. In this work, we report a protein‐templated synthesis of Mn‐doped ZnS quantum dots (QDs) by exploring bovine serum albumin (BSA) as the template. The obtained Mn‐doped ZnS QDs give phosphorescence emission centered at 590 nm, with a decay time of about 1.9 ms. A dual‐channel sensing system for two different proteins was developed through integration of the optical responses (phosphorescence emission and resonant light scattering (RLS)) of Mn‐doped ZnS QDs and recognition of them by surface BSA phosphorescent sensing of trypsin and RLS sensing of lysozyme. Trypsin can digest BSA and remove BSA from the surface of Mn‐doped ZnS QDs, thus quenching the phosphorescence of QDs, whereas lysozyme can assemble with BSA to lead to aggregation of QDs and enhanced RLS intensity. The detection limits for trypsin and lysozyme were 40 and 3 nM, respectively. The selectivity of the respective channel for trypsin and lysozyme was evaluated with a series of other proteins. Unlike other protein sensors based on nanobioconjugates, the proposed dual‐channel sensor employs only one type of QDs but can detect two different proteins. Further, we found the RLS of QDs can also be useful for studying the BSA–lysozyme binding stoichiometry, which has not been reported in the literature. These successful biosensor applications clearly demonstrate that BSA not only serves as a template for growth of Mn‐doped ZnS QDs, but also impacts the QDs for selective recognition of analyte proteins.
Intramolecular [2+2] Photocycloaddition of 3‐ and 4‐(But‐3‐enyl)oxyquinolones: Influence of the Alkene Substitution Pattern, Photophysical Studies, and Enantioselective Catalysis by a Chiral Sensitizer
Authors: Maturi Mark M. , Wenninger Matthias , Alonso Rafael , Bauer Andreas , Pöthig Alexander , Riedle Eberhard , Bach Thorsten 
Published: April 2013

AbstractThe intramolecular [2+2] photocycloaddition of four 4‐(but‐3‐enyl)oxyquinolones (substitution pattern at the terminal alkene carbon atom: CH2, Z‐CHEt, E‐CHEt, CMe2) and two 3‐(but‐3‐enyl)oxyquinolones (substitution pattern: CH2, CMe2) was studied. Upon direct irradiation at λ=300 nm, the respective cyclobutane products were formed in high yields (83–95 %) and for symmetrically substituted substrates with complete diastereoselectivity. Substrates with a Z‐ or E‐substituted terminal double bond showed a stereoconvergent reaction course leading to mixtures of regio‐ and diastereomers with almost identical composition. The mechanistic course of the photocycloaddition was elucidated by transient absorption spectroscopy. A triplet intermediate was detected for the title compounds, which–in contrast to simple alkoxyquinolones such as 3‐butyloxyquinolone and 4‐methoxyquinolone–decayed rapidly (τ≈1 ns) through cyclization to a triplet 1,4‐diradical. The diradical can evolve through two reaction channels, one leading to the photoproduct and the other leading back to the starting material. When the photocycloaddition was performed in the presence of a chiral sensitizer (10 mol %) upon irradiation at λ=366 nm in trifluorotoluene as the solvent, moderate to high enantioselectivities were achieved. The two 3‐(but‐3‐enyl)oxyquinolones gave enantiomeric excesses (ees) of 60 and 64 % at −25 °C, presumably because a significant racemic background reaction occurred. The 4‐substituted quinolones showed higher enantioselectivities (92–96 % ee at −25 °C) and, for the terminally Z‐ and E‐substituted substrates, an improved regio‐ and diastereoselectivity.
Molecular Design Rule of Phthalocyanine Dyes for Highly Efficient Near‐IR Performance in Dye‐Sensitized Solar Cells
Authors: Kimura Mutsumi , Nomoto Hirotaka , Suzuki Hiroyuki , Ikeuchi Takuro , Matsuzaki Hiroyuki , Murakami Takuro N. , Furube Akihiko , Masaki Naruhiko , Griffith Matthew J. , Mori Shogo 
Published: April 2013

AbstractA series of zinc–phthalocyanine sensitizers (PcS16–18) with different adsorption sites have been designed and synthesized in order to investigate the dependence of adsorption‐site structures on the solar‐cell performances in zinc–phthalocyanine based dye‐sensitized solar cells. The change of adsorption site affected the electron injection efficiency from the photoexcited dye into the nanocrystalline TiO2 semiconductor, as monitored by picosecond time‐resolved fluorescence spectroscopy. The zinc–phthalocyanine sensitizer PcS18, possessing one carboxylic acid directly attached to the ZnPc ring and six 2,6‐diisopropylphenoxy units, showed a record power conversion efficiency value of 5.9 % when used as a light‐harvesting dye on a TiO2 electrode under one simulated solar condition.
Use and need for psychosocial support in cancer patients
Authors: Ernst Johanna Christine , Beierlein Volker , Romer Georg , Möller Birgit , Koch Uwe , Bergelt Corinna 
Published: April 2013

BACKGROUNDCancer patients and their minor children have been shown to experience psychological distress. The objectives of the current study were to 1) describe the need for and use of psychosocial support and 2) determine predictors of family‐centered support use in patients with minor children.METHODSA population‐based sample of 1809 patients was recruited via 2 cancer registries. The eligibility criteria were age 25 years to 55 years, an initial diagnosis received no longer than 6 years before this survey, and having at least 1 minor child. Medical characteristics and self‐report measures were used.RESULTSOverall, approximately 38% cases were identified as being borderline or probable anxiety cases and 16% were identified as being borderline or probable depression cases. Since diagnosis, 44% of the patients had used psychosocial support and 9% had received family‐focused and child‐focused support. These patients perceived a lower quality of life and poorer family functioning. Approximately 73% of patients with children wanted information concerning or psychosocial services to support their children or parenting. Use of family‐centered support was not found to be predicted by disease‐related factors (eg, cancer staging) but rather by subjective needs (eg, mental health and having a distressed child in the family).CONCLUSIONSThe results of the current study emphasize the importance of child and parenting concerns in psychosocial care in oncology. Screenings for children and appropriate training programs for health care may increase awareness of this issue. Cancer 2013;119:2333–2341. © 2013 American Cancer Society.
Close margin alone does not warrant postoperative adjuvant radiotherapy in oral squamous cell carcinoma
Authors: Ch'ng Sydney , Corbett‐Burns Sophie , Stanton Norm , Gao Kan , Shannon Kerwin , Clifford Anthony , Gupta Ruta , Clark Jonathan R. 
Published: April 2013

BACKGROUNDThere are major variations between institutions regarding postoperative adjuvant therapy for adverse features in patients with oral squamous cell carcinoma (SCC). The authors' practice has been to not recommend any adjuvant therapy on the basis of close (<5 mm but uninvolved) margins unless there are additional adverse features. The primary objective of this study was to assess whether the local control achieved in this patient cohort was acceptable.METHODSIn this single‐institution, retrospective analysis, local control was the primary endpoint, and disease‐specific survival (DSS) was the secondary endpoint. Differences in survival were determined using the log‐rank test, and survival curves were generated using the Kaplan‐Meier method.RESULTSOne hundred forty‐four patients (79 men and 65 women; median age, 64.1 years; mean follow‐up, 3.3 years) underwent surgery alone for oral SCC with curative intent and were recorded as having close tumor margins on histology. The local control rate for all patients who underwent surgery alone was 91% (95% confidence interval, 81.9%‐95.2%), and the DSS rate was 84% (95% confidence interval, 74.0%‐89.9%) at 5 years. There was no pattern of worse local control or DSS rates with the ordered stratification of close margins. The 5‐year local control rates for having 0, 1, 2, and 3 additional adverse features were 100%, 96%, 83%, and 71%, respectively (P = .004; trend test).CONCLUSIONSSurgery alone without postoperative adjuvant therapy offered acceptable local control in patients who had close margin status as their only adverse feature and may be reasonable in the presence of 1 other adverse clinicopathologic feature. Cancer 2013;119:2427‐2437. © 2013 American Cancer Society.
Synthesis of Oxindoles through the Gold‐Catalyzed Oxidation of N‐Arylynamides
Authors: Yang Liu‐Qing , Wang Kai‐Bing , Li Chuan‐Ying 
Published: April 2013

Abstractα‐Oxo gold carbenoids generated by the oxidation of N‐arylynamides can be trapped intramolecularly at the ortho position of the aryl ring to give functionalized oxindoles under mild reaction conditions. Pyridine N‐oxide works as the oxidant, ligand, and base in this transformation.
Sea‐cliff retreat and shore platform widening: steady‐state equilibrium?
Authors: Dickson Mark E. , Ogawa Hiroki , Kench Paul S. , Hutchinson Andrew 
Published: April 2013

ABSTRACTWe challenge the notion of steady‐state equilibrium in the context of progressive cliff retreat on micro‐tidal coasts. Ocean waves break at or close to the abrupt seaward edge of near‐horizontal shore platforms and then rapidly lose height due to turbulence and friction. Conceptual models assume that wave height decays exponentially with distance from the platform edge, and that the platform edge does not erode under stable sea‐level. These assumptions combine to a steady‐state view of Holocene cliff retreat. We argue that this model is not generally applicable. Recent data show that: (1) exponential decay in wave height is not the most appropriate conceptual model of wave decay; (2) by solely considering wave energy at gravity wave frequencies the steady‐state model neglects a possible formative role for infragravity waves. Here we draw attention to possible mechanisms through which infragravity waves may drive cliff retreat over much greater distances (and longer timescales) than imaginable under the established conceptual model. Copyright © 2013 John Wiley & Sons, Ltd.
A developmental and energetic basis linking larval oyster shell formation to acidification sensitivity
Authors: Waldbusser George G. , Brunner Elizabeth L. , Haley Brian A. , Hales Burke , Langdon Christopher J. , Prahl Frederick G. 
Published: April 2013

AbstractAcidified waters are impacting commercial oyster production in the U.S. Pacific Northwest, and favorable carbonate chemistry conditions are predicted to become less frequent. Within 48 h of fertilization, unshelled Pacific oyster (Crassostrea gigas) larvae precipitate roughly 90% of their body weight as calcium carbonate. We measured stable carbon isotopes in larval shell and tissue and in algal food and seawater dissolved inorganic carbon in a longitudinal study of larval development and growth. Using these data and measured biochemical composition of larvae, we show that sensitivity of initial shell formation to ocean acidification results from diminished ability to isolate calcifying fluid from surrounding seawater, a limited energy budget and a strong kinetic demand for calcium carbonate precipitation. Our results highlight an important link between organism physiology and mineral kinetics in larval bivalves and suggest the consideration of mineral kinetics may improve understanding winners and losers in a high CO2 world.
‘BEHOLD, A VIRGIN IS WITH HIV!’ MISREPORTING SEXUAL BEHAVIOR AMONG INFECTED ADOLESCENTS
Authors: Tennekoon Vidhura , Rosenman Robert 
Published: April 2013

ABSTRACTIn four Southern African countries where the HIV prevalence rate is among the highest in the world, 46.4% of a sample of female adolescents infected with HIV report having never engaged in sex. This would indicate either the dominance of non‐sexual modes of HIV transmission or rampant misreporting of sexual behavior in the sample. We propose a method to estimate the extent of misreporting and calculate that the true percentages of virgins among the sample of HIV‐infected adolescent women is 32.1%. After accounting for misreporting, the contribution of sexual modes of HIV transmission is projected as 50.4%, compared with an estimate of 35.5% if we assume no misreporting. Copyright © 2013 John Wiley & Sons, Ltd.
Determination Limit of Fluorescence Turn‐On Probes for the Acetate Anion
Authors: Shang Xuefang , Yuan Jianmei , Du Zhimin , Wang Yingling , Jia Shenyu , Han Jie , Li Yue , Zhang Jinlian , Xu Xiufang 
Published: April 2013

AbstractThree fluorescent turn‐on probes containing 3,6‐dichloro‐9H‐carbazole as carbazyl part have been designed and synthesized. Among studied anions F−, AcO−, H2PO$\rm{{_{4}^{-}}}$, Cl−, Br− and I−, AcO− showed the strongest binding ability with all probes. The strong basic anions, such as AcO−, H2PO$\rm{{_{4}^{-}}}$, and F−, induced a significant red‐shift in absorption and a concomitant increase in fluorescent emission of the probes caused by photoinduced electron transfer (PET). The determination limit of probe 3 (Scheme 1) toward AcO− is 3.0×10−7 M. 1H‐NMR Titration experiments shed light on the nature of the interaction between the probes and the anions. Theoretical investigation further illustrated the possible binding mode in these hostguest interactions and the roles of molecular frontier orbitals in molecular interplay.
Synthesis and Characterization of Carbonyl Group‐6‐Metal Derivatives with LigandN,N‐Bis(diphenylphosphino)naphthalen‐1‐amine (=N‐(Diphenylphosphino)‐N‐naphthalen‐1‐yl‐P,P‐diphenylphosphinous Amide). Molecular Structure ofcis‐Tetracarbonyl[N‐(diphenylphosphino‐κP)‐N‐naphthalen‐1‐yl‐P,P‐diphenylphosphinous amide‐κP]molybdenum (cis‐[Mo(CO)4{C10H7‐1‐N(PPh2)2}])
Authors: Al‐Masri Harbi Tomah , Mohamed Beshir M. , Moussa Ziad , Alkordi Mohamed H. 
Published: April 2013

AbstractThe reaction ofN,N‐bis(diphenylphosphino)naphthalen‐1‐amine (1) with [M(CO)6] (M=Cr, Mo, W; 1 : 1 molar ratio) affordedcis‐[M(CO)4(1)]2(M=Cr),3(M=Mo), and4(M=W). Compounds2–4were identified and characterized by elemental analysis and multinuclear NMR (1H‐,13C‐, and31P‐NMR) and IR spectroscopy. A crystal‐structure determination of complex3was carried out.
ROUNDING, FOCAL POINT ANSWERS AND NONRESPONSE TO SUBJECTIVE PROBABILITY QUESTIONS
Authors: Kleinjans Kristin J. , Soest Arthur Van 
Published: April 2013

SUMMARYWe develop a panel data model explaining answers to subjective probabilities about binary events and estimate it using data from the Health and Retirement Study on six such probabilities. The model explicitly accounts for several forms of ‘reporting behavior’: rounding, focal point ‘50%’ answers and item nonresponse. We find observed and unobserved heterogeneity in the tendencies to report rounded values or a focal answer, explaining persistency in 50% answers over time. Focal 50% answers matter for some of the probabilities. Incorporating reporting behavior does not have a large effect on the estimated distribution of the genuine subjective probabilities. Copyright © 2013 John Wiley & Sons, Ltd.
THE ROLE OF INVENTORIES AND SPECULATIVE TRADING IN THE GLOBAL MARKET FOR CRUDE OIL
Authors: Kilian Lutz , Murphy Daniel P. 
Published: April 2013

SUMMARYWe develop a structural model of the global market for crude oil that for the first time explicitly allows for shocks to the speculative demand for oil as well as shocks to flow demand and flow supply. The speculative component of the real price of oil is identified with the help of data on oil inventories. Our estimates rule out explanations of the 2003–2008 oil price surge based on unexpectedly diminishing oil supplies and based on speculative trading. Instead, this surge was caused by unexpected increases in world oil consumption driven by the global business cycle. There is evidence, however, that speculative demand shifts played an important role during earlier oil price shock episodes including 1979, 1986 and 1990. Our analysis implies that additional regulation of oil markets would not have prevented the 2003–2008 oil price surge. We also show that, even after accounting for the role of inventories in smoothing oil consumption, our estimate of the short‐run price elasticity of oil demand is much higher than traditional estimates from dynamic models that do not account for for the endogeneity of the price of oil. Copyright © 2013 John Wiley & Sons, Ltd.