bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nanoscale characterization of interphase properties in maleated polypropylene‐treated natural fiber‐reinforced polymer composites
Authors: Nair Sandeep S. , Hurley Donna C. , Wang Siqun , Young Timothy M. 
Published: October 2012

AbstractContact resonance force microscopy has been used to evaluate the effect of maleated polypropylene (MAPP) concentration on interphase thickness as well as the spatial distribution of mechanical properties within the interphase of cellulose fiber‐reinforced polypropylene composites. The average interphase thickness values ranged from 25 nm to 104 nm for different concentrations of MAPP. The interphase region showed a gradient in the elastic modulus, with a gradual decrease in modulus from fiber to matrix. The interphase region in the specimen containing 0% MAPP showed a narrow interphase with steep gradient in modulus from fiber to matrix, whereas the use of MAPP significantly increased the interphase thickness which resulted in a more gradual change in modulus from fiber to matrix. POLYM. ENG. SCI., 2013. © Society of Plastics Engineers
Physical and dyeing properties of poly(ethylene terephthalate)/montmorillonite nanocomposite filament yarns
Authors: Özen İlhan , Güneş Servet 
Published: October 2012

AbstractThis research paper describes the generation of poly(ethylene terephthalate) (PET)/organoclay nanocomposite filaments by melt‐spinning method and investigation of their physical and dyeing properties. Two montmorillonite types of clay were modified using an intercalating agent synthesized and PET/organoclay (85/15 wt/wt) master batches were prepared using a corotating intermeshing twin screw extruder. Afterward, nanocomposite filaments containing different amounts of organoclay (0.5–5 wt%) were produced and dyed with two disperse dyes at atmospheric and high temperature dyeing conditions. Increased clay concentration led to reduced mechanical properties. Nonetheless, PET/organoclay nanocomposite filaments showed enhanced dyeability. POLYM. ENG. SCI., 2013. © Society of Plastics Engineers
Molecular structure–property engineering of low‐band‐gap copolymers, based on fluorene, for efficient bulk heterojunction solar cells: A density functional theory study
Authors: Mabrouk A. , Azazi A. , Alimi K. 
Published: October 2012

AbstractA comprehensive theoretical study of new donor (D)–acceptor (A) copolymers properties has been developed through quantum chemical calculations, on the basis of density functional theory (DFT). Fluorene and 2,1,3‐benzothiadiazole units were used as donor and acceptor units, respectively, in alternating D–A structures. The efficiency of D–A strength in the polymer was characterized, and their electronic properties are modulated through the insertion of thiophene, vinylene, or ethynylene as π‐spacer groups, in an attempt to reach the critical values, required for organic solar cells. Optoelectronic properties of these copolymers are rationalized on the basis of the patterns of their frontier orbitals. The analysis of the corresponding transition provides an efficient way for tracing the origin of various optical transitions of these copolymers and their photophysical properties. Bulk heterojunction photovoltaic cells, designed with the based fluorene‐copolymer as electron donor, blended with [6,6]‐phenyl‐C61‐butyric acid methyl ester as an electron acceptor, were energetically elucidated. A model band diagram was established, simulating the energy behavior of this active layer. POLYM. ENG. SCI., 2013. © Society of Plastics Engineers
Crystallization behavior and morphology of polylactide and PLA/clay nanocomposites in the presence of chain extenders
Authors: Najafi N. , Heuzey M.C. , Carreau P.J. 
Published: October 2012

AbstractThe effect of clay and chain extender on the nonisothermal, isothermal crystallization kinetics, and morphology of polylactide (PLA) was investigated in this study. PLA and PLA‐based nanocomposites containing 2 wt% organoclay were prepared via melt compounding. Three commercially available chain extenders were used: polycarbodiimide (PCDI), tris(nonylphenyl) phosphite (TNPP), and Joncryl ADR4368F. The nanoclay particles were found to act as nucleating agents. Chain extender incorporation, however, had diverse effects on both crystallization rate and degree of crystallinity. Nonisothermal DSC results revealed that the addition of PCDI increased the cold‐crystallization temperature (Tc) from 106 to 114°C, reduced the degree of crystallinity from 6.3 to 5.3%, and resulted in the formation of bimodal melting peaks in PLA. On the other hand, the reduction of chain ends in the presence of TNPP resulted in a significant increase of the crystallization rate and degree of crystallinity from 6.3 to 15.2%. In the case of Joncryl, its incorporation led to the formation of a long‐chain branching structure, which disrupted the chain packing. Therefore, the degree of crystallinity (from 6.3 to 1.6%) and the rate of crystallization decreased, while Tc was increased from 106 to 122°C in the presence of Joncryl. POLYM. ENG. SCI., 2013. © Society of Plastics Engineers
Highly enhanced accelerating effect of melt‐recrystallized stereocomplex crystallites on poly(L‐lactic acid) crystallization: effects of molecular weight of poly(D‐lactic acid)
Authors: Narita Junichi , Katagiri Mikio , Tsuji Hideto 
Published: October 2012

AbstractThe effects of the molecular weight of poly(D‐lactic acid) (PDLA), which forms stereocomplex (SC) crystallites with poly(L‐lactic acid) (PLLA), and those of processing temperature Tp on the acceleration (or nucleation) of PLLA homocrystallization were investigated using PLLA films containing 10 wt% PDLA with number‐average molecular weight (Mn) values of 5.47 × 105, 9.67 × 104 and 3.67 × 104 g mol–1 (PDLA‐H, PDLA‐M and PDLA‐L, respectively). For the PLLA/PDLA‐H and PLLA/PDLA‐M films, the SC crystallites that were ‘non’‐melted and those that were ‘completely’ melted at Tp values just above their endset melting temperature and recrystallized during cooling were found to act as effective accelerating (or nucleation) agents for PLLA homocrystallization. In contrast, SC crystallites formed from PDLA‐L, having the lowest Mn, were effective accelerating agents without any restrictions on Tp. In this case, the accelerating effects can be attributed to the plasticizer effect of PDLA‐L with the lowest Mn. The accelerating effects of SC crystallites in the PLLA/PDLA‐H and PLLA/PDLA‐M films was dependent on crystalline thickness for Tp values below the melting peak temperature of SC crystallites, whereas for Tp values above the melting peak temperature the accelerating effects are suggested to be affected by the interaction between the SC crystalline regions and PLLA amorphous regions.
Efficacy of methyl nonyl ketone as an in‐soil repellent for common voles (Microtus arvalis)
Authors: Fischer Daniela , Imholt Christian , Prokop Andreas , Jacob Jens 
Published: October 2012

AbstractBACKGROUND: Common voles (Microtus arvalis) can cause enormous damage in agriculture. Tests were conducted using an alternative approach to rodenticide‐based vole management by developing an in‐soil odour repellent based on the secondary plant metabolite methyl nonyl ketone (MNK). Replicated 25 m2 plots were established in forage grassland to test efficacy and application schemes using a foam application that included MNK.RESULTS: MNK significantly reduced the number of reopened burrow entrances in all field trials compared with untreated control plots, with repeated application for 6 days reducing vole activity by up to 90%. The addition of black pepper oil (BPO) did not enhance the efficacy of the MNK foam. Voles tended to avoid burrows where MNK was applied and rather opened new burrows instead of reopening the treated burrow entrances. The foam application scheme led to a repellent effect that lasted for about 4–5 days. A single additional application of MNK after 4 days can extend the treatment effects for a further 2 days.CONCLUSION: The results indicate that MNK has the potential to repel common voles in the field. However, more studies are needed to enhance the duration of a one‐off treatment effect to yield a user‐friendly field application to manage vole populations. © 2013 Society of Chemical Industry
Comparison of the RNA interference effects triggered by dsRNA and siRNA in Triboliumcastaneum
Authors: Wang Jinda , Wu Min , Wang Baoju , Han Zhaojun 
Published: October 2012

AbstractBackgroundEven though both dsRNA and siRNA have been widely used in laboratory studies to knock down target genes, it has been found that siRNA rarely triggers phenotypic changes for intact insects. In this study, Tribolium castaneum was used as a model species to compare dsRNA and siRNA and select the more efficient of these for insect RNAi.ResultsFour dsRNAs and ten siRNAs targeting the same three genes were tested by checking the suppression of target genes and the deformation of treated insects. The results showed that dsRNAs could reduce the expression of target genes by 55–75% for more than 7 days and deformed 78.8–87.0% of the larvae tested. Injection of their corresponding siRNAs targeting the same gene did yield about 45% silencing of target genes, but only in a short time period (from day 2 to day 4), and it did not trigger any phenotypic changes.ConclusionSiRNAs were less efficient than their corresponding dsRNAs. Most of them could hardly trigger any phenotypic changes owing to the temporary silencing effect on target genes. Meanwhile, the efficiency of different siRNAs varied with their matching sequence, and careful selection was necessary for proper use. © 2013 Society of Chemical Industry
A rapid diagnostic technique of Bactrocera cucurbitae and Bactrocera zonata (Diptera: Tephritidae) for quarantine application
Authors: Mezghani Khemakhem Maha , Ben Lazahr Wafa , Bouktila Dhia , Ben Slimen Hichem , Makni Hanem , Makni Mohamed 
Published: October 2012

AbstractBackroundThe melon fruit fly Bactrocera cucurbitae and the peach fruit fly Bactrocera zonata are serious pests, native to Asia, that have recently invaded Egypt. In Tunisia, no report of these species has yet been made, but pest risk data suggest that both Bactrocera species are likely to establish in other countries of the Mediterranean region.ResultsA quick method, based on a PCR‐RFLP of the mitochondrial COI gene, has been developed to enhance species identification for quarantine purposes. The restriction enzymes DdeI and XmnI were used to digest COI PCR products, enabling a rapid diagnosis of B. cucurbitae and B. zonata and their distinction from Tunisia's most devastating fruit pest, Ceratitis capitata.ConclusionThe simplicity and relatively low cost of this molecular approach will replace the need to rear immature stages through to adults for identification and will facilitate rapid quarantine decisions providing greater plant protection.
Effects of Mn‐doping on surface acoustic wave properties of ZnO films
Authors: Luo J. T. , Fan P. , Pan F. , Zeng F. , Zhang D. P. , Zheng Z. H. , Liang G. X. , Cai X. M. 
Published: October 2012

AbstractSurface acoustic wave (SAW) filters based on Mn‐doped ZnO films have been fabricated and effects of Mn‐doping on SAW properties are investigated. It is found that the electromechanical coupling coefficient (K2) of Zn0.913Mn0.087O films is 0.73 ± 0.02%, which is 73.8% larger than that of undoped ZnO films (0.42 ± 0.02%). Zn0.913Mn0.087O film filters also exhibit a lower absolute value of insertion loss (|IL|) of 16.1 dB and larger bandwidth (BW) of 5.9 MHz compared with that of undoped ZnO film filter. However, Zn0.952Mn0.048O film filters exhibit a smaller K2 of 0.34 ± 0.02%, larger |IL| of 26.9 dB and smaller BW of 3.5 MHz. It is suggested that the SAW properties can be improved by appropriate Mn‐doping and Mn–ZnO/Si multilayer structure with large d33 is promising for wide‐band and low‐loss SAW applications. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
An analysis of multi‐model ensembles for seasonal climate predictions
Authors: Yan Xiaoqin , Tang Youmin 
Published: October 2012

AbstractIn this study, the superiorities of the super‐ensemble for seasonal climate predictions are investigated based on the 500 mb geopotential height (GPH500) hindcasts produced by four Canadian atmospheric seasonal climate prediction models. The investigations are carried out mainly in two aspects: (i) a comprehensive evaluation of predictions for each grid point over the global domain by deterministic, probabilistic and potential prediction skill measures; (ii) the empirical orthogonal function (EOF) and the Maximum Signal‐to‐Noise (MSN) EOF analyses in the Northern Hemisphere. It is found that improvements of the super‐ensemble are mainly due to the increase of ensemble size in the mid‐high latitudes and the offsets of model uncertainties in the tropical regions. Measures of temporal correlation coefficient (CORR), Brier skill score (BSS) and reliability (REL) are more affected by the ensemble size; whereas the relative root‐mean‐square error (RRMSE) and resolution (RES) are sensitive to the offsets of model uncertainties. The first EOF mode of ensemble mean is similar to the most predictable pattern derived by the MSN EOF method, but the latter has the temporal evolutions more associated with the oceanic boundary forcing. The super‐ensemble shows advantages in both EOF and MSN EOF analyses.
Regional differences in the kinematic and thermodynamic structure of African easterly waves
Authors: Janiga Matthew A. , Thorncroft Chris D. 
Published: October 2012

AbstractThis study examines regional differences in the structure of African easterly waves (AEWs) at four locations between East Africa and the East Atlantic in a 12 yr (1998–2009) climatology. We focus on the cold‐core convectively active portions of the AEWs, which are typically found between 5 and 15°N. African easterly wave composites are produced from three reanalyses using the tracks of synoptic‐scale middle tropospheric vorticity maxima. The vertical structure of temperature and vorticity in the composite AEWs are related to regional differences in the climatological and vortex‐centred diabatic heating and diabatic potential vorticity (PV) generation profiles from the reanalyses. In addition, differences in AEW structure and activity between the three reanalyses are related to differences in rainfall and diabatic heating between the reanalyses. The climatological diabatic heating over East Africa, which is associated mostly with latent heating, peaks at 450 hPa with diabatic cooling below 750 hPa. In contrast, the convectively active West African coast and the East Atlantic have increased diabatic heating in the lower troposphere. Due to these regional differences in diabatic heating, diabatic PV generation peaks near 700 hPa over the continent and below 800 hPa over the East Atlantic. Moving westwards from East Africa to the East Atlantic, AEW composites have weaker lower tropospheric cold cores and significantly increased lower tropospheric vorticity within the convectively active troughs. The shape of the diabatic heating and PV generation profiles within the trough of the regional AEW composites are similar to the climatological profiles in each respective region. This suggests that regional differences in moist convection, particularly the land‐ocean contrast, provide a strong constraint on the diabatic process within the AEW trough and therefore the vertical structure of the AEWs.
High‐gain observer design for multi‐output systems: Transformation to a canonical form by dynamic output shaping
Authors: Grip Håvard Fjær , Saberi Ali 
Published: October 2012

SUMMARYIn this paper, we consider the observer design problem for a class of observable linear systems perturbed by nonlinear, time‐varying terms. Our design methodology is based on a canonical form, similar to canonical forms used elsewhere in the literature, that allows the nonlinearities to be dominated using high gain. We show that linear state and output transformations to this canonical form exist if, and only if, the data of the system satisfies a certain admissibility property. Moreover, the appropriate transformations can easily be constructed using available tools. We furthermore show that, if a system does not satisfy the admissibility property, it may be possible to extend it with an invertible output filter that makes the data of the extended system admissible. We refer to the problem of constructing such a filter as the output shaping problem and introduce an algorithm that solves the problem whenever it is solvable. Copyright © 2012 John Wiley & Sons, Ltd.
Curcumin disturbed cell‐cycle distribution of HepG2 cells via cytoskeletal arrangement
Authors: Jiang Jinhuan , Jin Hua , Liu Li , Pi Jing , Yang Fen , Cai Jiye 
Published: October 2012

SummaryDue to its extensive antitumor activity, curcumin has been focused on by more researchers. But, its antiproliferative mechanisms are still unknown. Here we studied the antiproliferative activity of curcumin in human liver cancer HepG2 cells. In order to analyze the cytotoxic activity and anticancer mechanisms of curcumin, we carried out cytotoxicity tests using 3‐[4,5‐dimethyl‐2‐thiazolyl]‐2,5 diphenyltetrazolium bromide (MTT) assay. The HepG2 cell cycle distribution and the expression of tubulin were detected by flow cytometry. Alterations in morphological and cytoskeletal properties of HepG2 cells were investigated using atomic force microscopy (AFM). Simultaneously, the effects of curcumin on the growth and proliferation of HepG2 cells were also assayed by MTT method. Cells were incubated with different doses of curcumin (0–80 μmol/l) for 24 h, the cell viability decreased from 91.10 ± 3.2% to 10.84 ± 4.0%, and the 50% inhibiting concentration (IC50) was 23.15 ± 0.37 μmol/l. Moreover, flow cytometry quantitatively detected that curcumin treatment resulted in a dose‐dependent accumulation of HepG2 cells in G2/M phase with concomitant losses from G0/G1 phase, so curcumin caused cell‐cycle arrest at G2/M phase. Furthermore, we discovered that curcumin was able to upregulate the expression of tubulin in HepG2 cells. In addition, AFM analysis including cell‐membrane structure and cytoskeleton networks is helpful to explain the relationship between the changes of cells and external pharmacologic stimulation. SCANNING 35: 253‐260, 2013. © 2012 Wiley Periodicals, Inc.
Improving strategies for diagnosing ovarian cancer: a summary of the International Ovarian Tumor Analysis (IOTA) studies
Authors: Kaijser J. , Bourne T. , Valentin L. , Sayasneh A. , Van Holsbeke C. , Vergote I. , Testa A. C. , Franchi D. , Van Calster B. , Timmerman D. 
Published: October 2012

ABSTRACTIn order to ensure that ovarian cancer patients access appropriate treatment to improve the outcome of this disease, accurate characterization before any surgery on ovarian pathology is essential. The International Ovarian Tumor Analysis (IOTA) collaboration has standardized the approach to the ultrasound description of adnexal pathology. A prospectively collected large database enabled previously developed prediction models like the risk of malignancy index (RMI) to be tested and novel prediction models to be developed and externally validated in order to determine the optimal approach to characterize adnexal pathology preoperatively. The main IOTA prediction models (logistic regression model 1 (LR1) and logistic regression model 2 (LR2)) have both shown excellent diagnostic performance (area under the curve (AUC) values of 0.96 and 0.95, respectively) and outperform previous diagnostic algorithms. Their test performance almost matches subjective assessment by experienced examiners, which is accepted to be the best way to classify adnexal masses before surgery. A two‐step strategy using the IOTA simple rules supplemented with subjective assessment of ultrasound findings when the rules do not apply, also reached excellent diagnostic performance (sensitivity 90%, specificity 93%) and misclassified fewer malignancies than did the RMI. An evidence‐based approach to the preoperative characterization of ovarian and other adnexal masses should include the use of LR1, LR2 or IOTA simple rules and subjective assessment by an experienced examiner. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.
Intra‐ and interobserver reproducibility of assessment of Doppler ultrasound findings in adnexal masses
Authors: Zannoni L. , Savelli L. , Jokubkiene L. , Di Legge A. , Condous G. , Testa A. C. , Sladkevicius P. , Valentin L. 
Published: October 2012

ABSTRACTObjectivesTo estimate intra‐ and interobserver reproducibility and reliability of assessment of the color content in adnexal masses at color/power Doppler ultrasound examination for observers with different levels of experience, and to determine if they change after a consensus meeting.MethodsDigital clips with color/power Doppler information on 103 adnexal masses were evaluated independently four times, twice before and twice after a consensus meeting, by four experienced and three less experienced ultrasound examiners. The color content of the adnexal mass was estimated using the International Ovarian Tumor Analysis color score and a 100‐mm visual analog scale (VAS score). Intraobserver repeatability was estimated for each observer. Interobserver agreement was estimated for the four most experienced observers (six pairs), for the three less experienced observers (three pairs), and for four other pairs of observers, each pair consisting of one of the experienced and one of the less‐experienced observers.ResultsIntra‐ and interobserver agreement for the color score was moderate to very good, percentage agreement ranging from 48 to 82.5% (kappa, 0.52–0.82) before and from 59 to 90% (kappa, 0.60–0.88) after the consensus meeting. For seven of 13 pairs of observers, interobserver agreement improved after the consensus meeting. Intraobserver intraclass correlation coefficient (ICC) values for the VAS score ranged from 0.80 to 0.92 before and from 0.75 to 0.94 after the consensus meeting, but limits of agreement were wide (± 20–35 mm). For six of the seven observers the ICC values were higher after the consensus meeting than before. Interobserver ICC values for the VAS score ranged from 0.77 to 0.88 before and from 0.77 to 0.91 after the consensus meeting, but limits of agreement were wide (± 30–40 mm). For 10 of 13 pairs of observers the ICC values improved after the consensus meeting.ConclusionsIntra‐ and interobserver agreement for the color score was good, especially after the consensus meeting, but there is room for improvement. VAS score results varied substantially within and between observers both before and after the consensus meeting. General consensus needs to be reached about how to interpret color/power Doppler ultrasound findings in adnexal masses. Copyright © 2013 ISUOG. Published by John Wiley & Sons Ltd.