bluuebunny/crossref_metadata_2025_split huggingface dataset:
Variations in morphology and composition of barley endosperm cell walls
Authors: Lazaridou Athina , Chornick Tricia , Izydorczyk Marta S 
Published: September 2008

AbstractBACKGROUND: The endosperm cell walls (CWs) impact upon barley grain utilization as well as influence animal and human nutrition. The objective of this study was to examine the morphological and compositional differences in the endosperm CWs derived from barley grain grown in different (uncontrolled) environments in Canada, and differing in grain hardness, protein, and total β‐glucan contents.RESULTS: The endosperm CWs were isolated from barley, cv. Metcalfe, grown in Davidson, SK (sample A), Hythe, AB (sample B), and Hamiota, MB (sample C). The inner wall surfaces of sample A exhibited deep indentations made by large and small starch granules, whereas the CWs of sample B were thicker, had smooth surface, and exhibited a greater degree of binding between the adjoining cells. The CWs of sample A contained the lowest amount of β‐glucans but the highest amount of arabinoxylans and the mannose‐containing (glucomannans) polysaccharides. The CWs of sample B contained the highest ratio of ferulic and dehydrodiferulate residues to Xyl residues among the samples, indicating the greatest potential and degree of cross‐linking of arabinoxylans in these preparations which might be related to the strength and rigidity of the grain endosperm. The amino acid composition of the proteins detected in the isolated CW indicated the presence of 37–47 g kg−1 of structural proteins.CONCLUSIONS: Substantial differences in the morphological appearance and chemical composition of the CW preparations were observed and some attempts were made to relate these differences to the variable composition and physical properties of barley grain as affected by the environmental factors. Copyright © 2008 Crown in the Right of Canada, Canadian Grain Commission. Published by John Wiley and Sons, Ltd
The impact of margin status on local recurrence following breast conserving therapy for invasive carcinoma in Manitoba
Authors: Hardy K. , Fradette K. , Gheorghe R. , Lucman L. , Latosinsky S. 
Published: September 2008

AbstractBackgroundHistologically positive margins are generally considered unacceptable with breast conserving therapy (BCT) given the increased risk of local recurrence (LR). What constitutes an adequate negative margin remains controversial. Margin status was explored as a predictor of LR post‐BCT.MethodsManitoba women with loco‐regional progression and/or mastectomy >6 months following BCT for Stage I/II invasive cancer (1995–2004) were identified from the Manitoba Cancer Registry; LR cases were confirmed by chart review. Three controls per case were matched by age, grade, stage, and adjuvant chemotherapy use. Margin status was categorized as histologically positive, ≤1 mm, ≤2 mm or >2 mm. Conditional logistic regression determined the odds ratio of LR by margin category.ResultsThere were 50 LR cases in 3,017 patients who underwent BCT, with a median follow‐up of 60 months. Wider margins were associated with a non‐significant reduction in LR: >1 mm versus ≤1 mm (OR 0.69; 95% CI 0.28–1.69) and >2 mm versus ≤2 mm (OR 0.90; 95% CI 0.44–1.84).ConclusionsNo clear benefit to wider histologically negative margins is demonstrated. J. Surg. Oncol. © 2008 Wiley‐Liss, Inc.
Recurrence in patients following curative resection of early gastric carcinoma
Authors: Wu Benyan , Wu Daohong , Wang Mengwei , Wang Gangshi 
Published: September 2008

AbstractObjectivePost‐gastrectomy recurrences of early gastric cancer occur in a few cases. We investigated the outcome of early gastric cancer patients treated surgically, with special respect to the risk factor(s) for tumor recurrence.Patients and MethodsA total of 308 patients with mono‐foci early gastric cancer underwent curative surgical resection. Clinicopathological variables and tumor recurrence patterns were analyzed retrospectively.ResultsRecurrence was observed in 30 out of 245 patients (12.24%) who had completed follow‐up. The median interval from surgery to diagnosis of recurrence was 28 (range 3–188) months. Hematogenous recurrence (3.27%) was twice as frequent as peritoneal recurrence (1.63%). Gastric stump cancer occurred in 9 patients (3.67%), anastomotic recurrence in 7 patients (2.86%) and lymphatic recurrence in 4 patients (1.63%). Older patients (≥60 years old) had a more frequent recurrence rate than younger patients (P < 0.05). Multivariate analyses identified lymph node metastasis and depth of invasion as risk factors of recurrence. All the patients with a positive family history of cancer got recurrence within 3 years after surgery.ConclusionsEarly gastric cancer patients, who were elderly, had lymphatic and submucosal involvement, and patients with a positive family history of cancer, tended to have a greater risk of recurrence. J. Surg. Oncol. © 2008 Wiley‐Liss, Inc.
Single sample extraction protocol for the quantification of NAD and NADH redox states in Saccharomyces cerevisiae
Authors: Sporty Jennifer L. , Kabir Md. Mohiuddin , Turteltaub Kenneth W. , Ognibene Ted , Lin Su‐Ju , Bench Graham 
Published: September 2008

AbstractA robust redox extraction protocol for quantitative and reproducible metabolite isolation and recovery has been developed for simultaneous measurement of nicotinamide adenine dinucleotide (NAD) and its reduced form, NADH, from Saccharomyces cerevisiae. Following culture in liquid media, yeast cells were harvested by centrifugation and then lysed under nonoxidizing conditions by bead blasting in ice‐cold, nitrogen‐saturated 50 mM ammonium acetate. To enable protein denaturation, ice cold nitrogen‐saturated CH3CN/50 mM ammonium acetate (3:1 v/v) was added to the cell lysates. Chloroform extractions were performed on supernatants to remove organic solvent. Samples were lyophilized and resuspended in 50 mM ammonium acetate. NAD and NADH were separated by HPLC and quantified using UV–Vis absorbance detection. NAD and NADH levels were evaluated in yeast grown under normal (2% glucose) and calorie restricted (0.5% glucose) conditions. Results demonstrate that it is possible to perform a single preparation to reliably and robustly quantitate both NAD and NADH contents in the same sample. Robustness of the protocol suggests it will be (i) applicable to quantification of these metabolites in other cell cultures; and (ii) amenable to isotope labeling strategies to determine the relative contribution of specific metabolic pathways to total NAD and NADH levels in cell cultures.
Rapid and sensitive analysis of multiple bioactive constituents in Compound Danshen preparations using LC‐ESI‐TOF‐MS
Authors: Xia Li , Liu Hai‐Ling , Li Ping , Zhou Jian‐Liang , Qi Lian‐Wen , Yi Ling , Chen Jun 
Published: September 2008

AbstractBy fully optimizing the separation and analytical conditions, a rapid‐resolution LC (RRLC, 1.8 μm particle size) coupled with TOF‐MS method was developed and validated for multiple compounds analysis of traditional Chinese medicinal compound preparations (TCMCPs). As a typical example, determination of Compound Danshen preparations (CDPs, mainly comprising Salvia miltiorrhiza and Panax notoginseng), was improved on three groups of bioactive constituents (phenolic acids, diterpenoids, and saponins). LODs down to 1.2 pg, permitting very good separation of 20 analytes and 3 internal standards (ISs) in 17 min, represented an approximate five‐fold reduction of time compared to conventional HPLC. Unequivocal identification of target compounds in CDPs was based on accurate mass measurement of ions, and comparison of retention performance with available standards. Quantitation was carried out using the narrow window extracted ion chromatograms (XICs) of each compound with an interference‐free baseline (using a ±0.02 Da window) yielding good linearity of response (r2 >0.9940), and excellent precision of retention time (tR) both interday (RSD, 0.01–0.19%) and intraday (RSD, 0.02–1.08%). The acceptable recoveries obtained were in the range of 77.69–113.8%. The results demonstrated the robustness and applicability of RRLC‐TOF‐MS for multicomponents analysis in TCMCPs with diverse chemical compositions and properties.
Fast field analysis of short‐chain aliphatic amines in water using solid‐phase microextraction and a portable gas chromatograph
Authors: Lin Huaqing , Deng Chunhui , Zhang Xiangmin 
Published: September 2008

AbstractA novel method is firstly presented for field and rapid analysis of short‐chain aliphatic amines in water as their pentafluorobenzaldehyde (PFBAY) derivative using solid‐phase microextraction (SPME) and portable GC. In the proposed method, short‐chain aliphatic amines in water rapidly reacted with PFBAY, and then were headspace extracted and concentrated by SPME. The formed amines derivatives were analyzed by portable GC. The SPME parameters of fiber selection, extraction temperature, extraction time, and stirring rate were studied. The method validations including LOD, recovery, precision, and linearity were studied. It was found that the proposed method required the whole analysis time 22 min, and provided low LOD of 1.2–4.6 ng/mL, good recovery of 91–106%, good precision of RSD value 3.5–9.3%, and linear range 20.0–500 ng/mL (r2 >0.99). The obtained results demonstrated that the SPME‐portable GC is a simple, rapid, and efficient method for the field analysis of short‐chain aliphatic amines. Finally, the proposed method was further applied to the quantification of ethylamine, propylamine, and butylamine in environmental water.
To go or stay home and watch: exploring the balance between motives and perceived constraints for major events: a case study of the 2008 Beijing Olympic Games
Authors: Funk Daniel C. , Alexandris Konstantinos , Ping Yang 
Published: September 2008

AbstractThe current study offers insight into the role of motivation and constraints on behavioural intentions prior to a mega event. The Psychological Continuum Model framework was used to integrate motivation and leisure constraints theory to examine attraction towards the 2008 Olympic Games. Semi‐structured interviews (N = 47) and a questionnaire (N = 235) distributed in Australia and the USA were used to identify and measure three motivational themes: cultural learning, cultural experience and olympic event interest, and three perceived constraints: structural, interpersonal and intrapersonal. Structural Equation Modelling revealed that motives were positively related to behavioural intentions while constraints were negatively related. Analysis further revealed the interaction between motives and perceived constraints led to two different forms of behavioural intentions; intentions to travel and attend the event vs. stay home to watch the event on TV. Policy and marketing implications are discussed that illustrate the benefits of understanding both motives and perceived constraints for tourism travel. Copyright © 2008 John Wiley and Sons, Ltd.
Type of diversification and firm resources: new empirical evidence from the Spanish tourism industry
Authors: Andreu Rosario , Claver Enrique , Quer Diego 
Published: September 2008

AbstractThis paper analyses the diversification strategies followed by tourism firms from the perspective of the resource‐based view. More specifically, it seeks to verify whether the composition of the firms' resources has a bearing on the decision to undertake one type of diversification or another (related or unrelated). From a mail survey to 80 Spanish tourism firms, we identified 94 entries into new business areas. We applied an ordered logit regression and have statistically confirmed that intangible resources lead to a more related type of diversification. Copyright © 2008 John Wiley & Sons, Ltd.
Tourism and the state in Cuba: from the past to the future
Authors: Sharpley Richard , Knight Martin 
Published: September 2008

AbstractIt has long been recognised that nature and extent of state intervention in tourism development closely reflects the prevailing political‐economy and ideology within the destination state. This is certainly the case with Cuba which, since the 1959 revolution and despite the collapse of communism elsewhere, remains the world's only centrally‐planned economy that boasts a significant international tourism sector. Tracing the development of tourism since 1959, this paper explores the relationship between the evolution of Cuba's political‐economic structures and processes and their subsequent influence on the planning, control, development and ownership of tourism on the island. In particular, it considers the potential future of tourism in Cuba, challenging the widespread belief that, in a post‐Castro era, the island's tourism sector faces a bright future. It concludes that, even with a potential move towards market reform, significant improvements will be required with respect to the quality, value and diversity of the island's tourism product. Copyright © 2008 John Wiley & Sons, Ltd.
Anisotropic Photomechanical Response of Stretched Blend Film Made of Polycaprolactone‐Polyvinyl Ether with Azobenzene Group as Side Chain
Authors: Tanaka Shimon , Kim Hyun‐Kyoung , Sudo Astushi , Nishida Haruo , Endo Takeshi 
Published: September 2008

AbstractA rapid and reversible anisotropic photomechanical response of polymer film was achieved by using uniaxially stretched blend film composed of polycaprolactone and poly(vinyl ether) with azobenzene moiety (Azo‐PVE) as a side chain. The photomechanical response behavior of the film was studied under a constant tensile stress. The deformation or recovery was rapidly completed within at most 0.1 min of UV + Vis light irradiation being switched on or off, respectively. The anisotropy of deformation was confirmed on a stretched film subjected to light irradiation. The deformation was observed as a contraction in a direction parallel to the stretching direction and as an elongation in the perpendicular direction. The anisotropy of the photoresponse was remarkably observed with increase in the stretching ratio, reflecting the binding between amorphous areas by Azo‐PVE long chains.magnified image
Photoinitiated Cationic Polymerization of Mono and Divinyl Ethers in Aqueous Medium Using Ytterbium Triflate as Lewis Acid
Authors: Kahveci Muhammet U. , Tasdelen M. Atilla , Cook Wayne D. , Yagci Yusuf 
Published: September 2008

AbstractPhotoinitiated cationic polymerization of vinyl ethers in aqueous medium by using diphenyliodonium iodide (DPII) in the presence of a water‐tolerant Lewis acid, ytterbium triflate (Yb(OTf)3), was reported. The polymerizations were performed in heterogeneous systems consisting of an aqueous phase containing Yb(OTf)3 and photoinitiator and an organic phase of acetonitrile containing monomer. The polymerization consists of two‐steps; (i) photoinduced adduct formation and (ii) subsequent propagation with the aid of Yb(OTf)3. The fast polymerization exhibited an explosive character so that the monomer conversion and molecular weights of the resulting polymers are very dependent on the experimental conditions, such as temperature, stirring manner and rate.magnified image
Increased Electrical Conductivity in Poly(3,4‐ethylenedioxythiophene) upon Cross‐Linking
Authors: Mendez James D. , Weder Christoph 
Published: September 2008

AbstractCross‐linked poly(3,4‐ethylenedioxythiophene) (PEDOT) films were synthesized by the oxidative polymerization of 3,4‐ethylenedioxythiophene in the presence of five different conjugated and non‐conjugated cross‐linkers. The concentration and structure of the cross‐linker was systematically varied to explore the influence on the electrical conductivity. Optimized compositions displayed an electrical conductivity of up to ≈800 S · cm−1; this corresponds to a conductivity increase of up to 36% compared to linear PEDOT prepared under identical conditions. An increase in the conductivity was only observed for the conjugated cross‐linkers that were incorporated in low concentrations, typically at a level of less than 2 mol‐%. Attempts to incorporate higher concentrations of cross‐linker led to phase separation and crystallization of the cross‐linker and afforded materials in which a significant reduction of the electrical conductivity was observed. The optical properties of the polymer were only marginally affected upon cross‐linking, even at high cross‐linker concentrations.magnified image
Aging Effects on the Phase Composition and Chain Mobility of Isotactic Poly(propylene)
Authors: Hedesiu Cristian , Demco Dan E. , Kleppinger Ralf , Poel Geert Vanden , Remerie Klaas , Litvinov Victor M. , Blümich Bernhard , Steenbakkers Rieky 
Published: September 2008

AbstractChanges in phase composition and chain mobility in injection‐molded isotactic poly(propylene), crystallized from the melt with slow cooling rate and subsequently quenched, associated with aging at temperature well above Tg for 150 and 1 000 h, are studied using time‐domain 1H solid‐state NMR and XRD. All sample exhibit physical aging when exposed to elevated temperatures, and the physical aging kinetics was observed to depend on the morphology of the homopolymer iPP and aging temperatures. The significant increase in the tensile modulus in time was observed for injection‐molded iPP. The observed property changes induced by aging are attributed to microstructural changes within the semi‐rigid and amorphous fractions.magnified image
Polyurethanes with Narrow‐ and Polydisperse Hard Segment Distributions
Authors: De Debasish , Gaymans Reinoud J. 
Published: September 2008

AbstractPolyurethanes with narrow‐disperse (ND) and polydisperse (PD) hard segment (HS) distributions were prepared in a two‐step process. First, a poly(propylene oxide) end‐capped with MDI (4,4′methylenebis(phenyl isocyanate) was synthesized. To this prepolymer either a diamine–diamide was added to form ND HSs or a mixture of a diamine–diamide and additional MDI to form PD HSs in the copolymers. The polyurethanes displayed a ribbon‐like crystalline morphology, and it was found that the copolymers with ND HSs were more crystalline, had a higher modulus, a less temperature‐dependant modulus, and a higher melting temperature than their PD counterparts. Overall, the polyurethanes with the narrow‐dispersed HSs displayed superior properties.magnified image
Rheological Features and Flow‐Induced Crystallization of Branched Poly[ethylene‐co‐(1,4‐cyclohexanedimethylene terephthalate)] Copolyesters
Authors: Quintana Robert , de Ilarduya Antxon Martínez , Guerra Sebastián Muñoz , Fernández Mercedes , Muñoz María Eugenia , Santamaría Anton 
Published: September 2008

AbstractA set of amorphous poly[ethylene‐co‐(1,4‐cyclohexanedimethylene terephthalate)] (PECT) copolymers containing 25 and 30% of 1,4‐cyclohexane dimethylene (CHDM) units and small amounts of branching agent pentaerythritol (PER) is investigated. The level of long chain branching was estimated by analyzing the positive deviation from $\eta _0 \sim\overline M _{\rm w}^{3.54}$ law. Branching also produced melt elasticity enhancement which is desirable for certain processing methods. Capillary extrusion experiments at 180 °C generated flow‐induced crystallization in PECT containing 25% of CHDM. Crystallization increased with the amount of PER added, which was explained by the favorable effect of branching to increase elongational rate at the entrance of the capillary. Linear and branched PECTs containing 30% of CHDM did not crystallize.magnified image
Novel in situ NMR Measurement System for Evaluating Molecular Mobility during Drawing from Highly Entangled Polyethylene Melts
Authors: Kakiage Masaki , Uehara Hiroki , Yamanobe Takeshi 
Published: September 2008

AbstractA novel in situ measurement system for evaluating molecular mobility during uniaxial drawing of polymeric materials was established by introducing drawing and stress‐detecting devices into a 1H pulse nuclear magnetic resonance spectrometer. In this study, we analyze the changes in molecular motion of amorphous chains during melt‐drawing of ultra‐high molecular weight polyethylenes (UHMW‐PEs) with different molecular weight distributions. In the initial stage of drawing, a three‐component resolution was possible for the relaxation decay curve, which includes “rigid”, “intermediate”, and “mobile” amorphous components. The quality and quantity changes in these components demonstrated that this intermediate amorphous component could be regarded as the index of the change in molecular entanglement characteristics during the orientation of PE chains.magnified image
Thermoreversible Contraction and Extension of Layer Spacing in Smectic Phase of Side Chain Liquid Crystal Poly(fumarate)s
Authors: Michinobu Tsuyoshi , Fujii Nozomu , Tokita Masatoshi , Watanabe Junji , Shigehara Kiyotaka 
Published: September 2008

AbstractTwo types of liquid crystal poly(fumarate)s having cyanobiphenyl mesogen in side chain were prepared by radical polymerization of disubstituted fumarate monomers in bulk. The mesogen is thus connected via alkyl spacer to every carbon atom in the main chain. The liquid crystalline temperature range expands with an increase in the molecular weight and with alkyl chain spacer length. The poly(fumarate)s form a smectic Ad phase whose layer spacing decreases and increases on heating and cooling, respectively. The contraction ratio is up to 15.2%. This significantly large change in the layer spacing corresponds to temperature dependence of the orientational order parameter. It may be connected to high density of the mesogen hanging from the main chain.magnified image
Taking Advantage of Tailored Electrostatics and Complementary Hydrogen Bonding in the Design of Nanostructures for Biomedical Applications
Authors: Hunley Matthew T. , Karikari Afia S. , McKee Matthew G. , Mather Brian D. , Layman John M. , Fornof Ann R. , Long Timothy E. 
Published: September 2008

AbstractFour‐armed, star‐shaped poly(D,L‐lactide) (PDLLA) was synthesized and terminally‐functionalized with either adenine or thymine complementary hydrogen bonding groups (PDLLA‐A and PDLLA‐T, respectively). The strong hydrogen bonding led to increased viscosity below the dissociation temperature of the hydrogen bonds. Rheology confirmed that these bonds were thermally reversible, with a sharp reduction in viscosity near 100 °C. PDLLA, PDLLA‐A, and PDLLA‐T were melt electrospun with no significant change in fiber diameter (all between 3.6 and 4.0 µm). However, a blend of PDLLA‐A and PDLLA‐T formed fibers with an average diameter of 9.8 ± 2.0 µm, resulting from the hydrogen bond associations. Also, the phospholipid 1‐palmitoyl‐2‐oleoyl‐sn‐glycero‐3‐phosphoethanolamine (POPE) was melt electrospun at 200 °C and formed uniform fibers with average fiber diameter of 6.5 ± 2.0 µm.
Supramolecular Assembly and Hybridization in Giant Nanomembranes
Authors: Kunitake Toyoki 
Published: September 2008

AbstractWe demonstrated recently that large nanomembranes became available from inorganic, organic/inorganic and totally organic precursors. Spin coating of mixtures of acrylate monomers and zirconium butoxide (or tetraethoxysilane), when combined with simultaneous radical polymerization and sol‐gel reaction, gave 10–30 nm thick, free‐standing nanomembranes composed of metal oxides and crosslinked acrylates as interpenetrating network. This approach was extended to thermosetting resins (epoxy, melamine and phthalic resins), to fabricate robust, free‐standing nanomembranes. Mechanical properties of the nanomembranes as measured by the bulge test and by a compression method were comparable to those of the corresponding macroscopic resins.The hybrid nanomembrane was subsequently prepared by supramolecular assembly of the nanofilm with surfactants and lipids. These amphiphiles produced adsorbed monolayers on the nanomembrane and some of the assemblies were stably kept in water.
Self‐Assembly of Inorganic Nanocrystals: Emergence of a New Physics
Authors: Pileni M. P. 
Published: September 2008

AbstractIn this paper we demonstrate that ordering of nanocrystals on long distance in 3D superlatices called supra crystals permit to emerge of collective intrinsic properties, which was not expected. The shape of the organization at the mesoscopic scale also induces new physical properties.