bluuebunny/crossref_metadata_2025 huggingface dataset:
Social influence and bullying behavior: Intervention‐based network dynamics of the fairplayer.manual bullying prevention program
Authors: Wölfer Ralf , Scheithauer Herbert
Published: January 2014

Bullying is a social phenomenon and although preventive interventions consequently address social mechanisms, evaluations hardly consider the complexity of peer processes. Therefore, the present study analyzes the efficacy of the fairplayer.manual bullying prevention program from a social network perspective. Within a pretest–posttest control group design, longitudinal data were available from 328 middle‐school students (MAge = 13.7 years; 51% girls), who provided information on bullying behavior and interaction patterns. The revealed network parameters were utilized to examine the network change (MANCOVA) and the network dynamics (SIENA). Across both forms of analyses, findings revealed the hypothesized intervention‐based decrease of bullies' social influence. Hence the present bullying prevention program, as one example of programs that successfully addresses both individual skills and social mechanisms, demonstrates the desired effect of reducing contextual opportunities for the exhibition of bullying behavior. Aggr. Behav. 40:309–319, 2014. © 2014 Wiley Periodicals, Inc.
A General and Practical Palladium‐Catalyzed Direct α‐Arylation of Amides with Aryl Halides
Authors: Zheng Bing , Jia Tiezheng , Walsh Patrick J.
Published: January 2014

An efficient system for the direct catalytic intermolecular α‐arylation of acetamide derivatives with aryl bromides and chlorides is presented. The palladium catalyst is supported by Kwong’s indole‐based phosphine ligand and provides monoarylated amides in up to 95% yield. Excellent chemoselectivities (>10:1) in the mono‐ and diarylation with aryl bromides were achieved by careful selection of bases, solvents, and stoichiometry. Under the coupling conditions, the weakly acidic α‐protons of amides (pKa up to 35) were reversibly depotonated by lithium tert‐butoxide (LiO‐t‐Bu), sodium tert‐butoxide (NaO‐t‐Bu) or sodium bis(trimethylsilyl)amide [NaN(SiMe3)2].

magnified image
Assessing Changes in Dairy Product Import Demand: The Case of South Korea with Implementation of the KORUS FTA
Authors: Jones Kiethly G. , Blayney Don
Published: January 2014

The impacts of implementing the Korea‐U.S. Free Trade Agreement (KORUS FTA) on South Korea's dairy trade are assessed in this study based on empirical estimates of short‐run and long‐run source‐based import demand parameters for three major imported dairy products. These estimates were derived using the Central Bureau of Statistics (CBS) demand system model. The impacts of the tariff reductions associated with the KORUS FTA were calculated. The results suggest that the KORUS FTA will open South Korean dairy product markets primarily by reducing import prices of international suppliers’ products. The altered import relationships among those suppliers raises overall dairy product imports into South Korea. [EconLit Classifications: F14, Q17].
A simple model for simulation of particle deaggregation of few‐particle aggregates
Authors: Kaunisto Erik , Rasmuson Anders , Bergenholtz Johan , Remmelgas Johan , Lindfors Lennart , Folestad Staffan
Published: January 2014

A proper mechanistic understanding of the deaggregation process of small colloidal particle aggregates is of generic importance within many fields of science and engineering. The methodology for modeling colloidal deaggregation is currently limited to analytical solutions in the two‐particle case and time consuming numerical algorithms, such as Brownian Dynamics (BD) simulations, for many‐particle aggregates. To address this issue, a simplified alternative model that describes deaggregation of few‐particle aggregates is presented. The model includes end‐particle deaggregation and a particle reconfiguration mechanism, which are the two most important mechanisms for deaggregation. Comparison of the calculated first passage time distribution for various two‐, three‐, four‐, and five‐particle aggregates with the corresponding result using BD simulations confirms the validity of the model. It is concluded that the dominating mechanism behind deaggregation can be quantified using a deaggregation number, which reflects the time scale for reconfiguration relative to the time scale for end‐particle deaggregation. © 2014 American Institute of Chemical Engineers AIChE J, 60: 1863–1869, 2014
Methylglyoxal‐augmented manuka honey as a topical anti–Staphylococcus aureus biofilm agent: safety and efficacy in an in vivo model
Authors: Paramasivan Sathish , Drilling Amanda Jane , Jardeleza Camille , Jervis‐Bardy Josh , Vreugde Sarah , Wormald Peter John
Published: January 2014

Background

Bacterial biofilms are thought to contribute to recalcitrance in chronic rhinosinusitis (CRS) patients. Manuka honey (MH) and its active component methylglyoxal (MGO) have demonstrated antibiofilm activity in vitro. This study evaluated the safety and efficacy of these agents in an in vivo model.

Methods

To assess safety, ovine frontal sinuses were flushed twice daily for 14 days. In each sheep, 1 sinus was flushed with a panel of MGO concentrations ranging from 0.5 to 7.2 mg/mL alone and flushed with a panel of with 16.5% wt/vol MH enriched with MGO at the same range of concentrations (0.5–7.2 mg/mL; designated MH/MGO). Contralateral sinuses were flushed with saline control. Tissue morphology was assessed histologically and with scanning electron microscopy. Efficacy was tested by developing Staphylococcus aureus biofilms in sheep sinuses. Twice‐daily irrigation for 5 days was commenced with either saline, MGO (0.5–3.6 mg/mL) alone, or MH/MGO (with 0.5–3.6 mg/mL MGO). Biofilm biomass was compared between the groups (n = 4) using LIVE/DEAD BacLight staining and confocal scanning laser microscopy.

Results

The results of the safety assessment, for normal sinuses treated with MGO alone or with MH/MGO (≤1.8 mg/mL) showed normal pseudostratified epithelium and cilia structure; however, higher concentrations caused cilia denudation and squamous metaplasia. As for efficacy, when compared to saline flush, treatment with MH/MGO at 0.9 mg/mL (0.608 ± 0.110 vs 0.316 ± 0.197 μm3/μm2, respectively; p = 0.015) and 1.8 mg/mL (0.676 ± 0.079 vs 0.114 ± 0.033 μm3/μm2, respectively; p = 0.001) significantly reduced biofilm biomass.

Conclusion

Sinus irrigation with MH/MGO at MGO concentrations between 0.9 and 1.8 mg/mL is both safe to mucosa and efficacious against S. aureus biofilm. MH/MGO irrigation could represent a viable treatment option for recalcitrant CRS.
Factors associated with early progression of non‐small‐cell lung cancer treated by epidermal growth factor receptor tyrosine‐kinase inhibitors
Authors: Rozensztajn Nathalie , Ruppert Anne‐Marie , Lavole Armelle , Giroux Leprieur Etienne , Duruisseaux Michael , Vieira Thibault , Rabbe Nathalie , Lacave Roger , Antoine Martine , Cadranel Jacques , Wislez Marie
Published: January 2014

Epidermal growth factor receptor tyrosine‐kinase inhibitors (EGFR‐TKI) are a therapeutic option as second‐line therapy in non‐small‐cell lung carcinoma (NSCLC), regardless of the EGFR gene status. Identifying patients with early progression during EGFR‐TKI treatment will help clinicians to choose the best regimen, TKI or chemotherapy. From a prospective database, all patients treated with gefitinib or erlotinib between 2001 and 2010 were retrospectively reviewed. Patients were classified into two groups according to their tumor response by RECIST after 45 days of treatment, progressive disease (PD) or controlled disease (CD). Two hundred and sixty‐eight patients were treated with EGFR‐TKI, among whom 239 were classified as PD (n = 75) and CD (n = 164). Median overall survival was 77 days (95% CI 61–109) for PD and 385 days (95% CI 267–481) for CD. Patients with PD were of younger age (P = 0.004) and more frequently current smokers (P = 0.001) had more frequently a performance status ≥2 (P = 0.012), a weight loss ≥10% (P = 0.025), a shorter time since diagnosis (P < 0.0001), a pathological classification as non‐otherwise‐specified NSCLC (P = 0.01), and the presence of abdominal metastases (P = 0.008). In multivariate analysis, abdominal metastases were the only factor associated with early progression (odds ratio (OR) 2.17, 95% CI [1.12–4.19]; P = 0.021). Wild‐type EGFR versus mutated EGFR was associated with early progression. The presence of abdominal metastasis was independently associated with early progression in metastatic NSCLC receiving EGFR‐TKI.
Pattern recognition methods and multivariate image analysis in HPTLC fingerprinting of propolis extracts
Authors: Ristivojević Petar , Andrić Filip Lj. , Trifković Jelena Đ. , Vovk Irena , Stanisavljević Ljubiša Ž. , Tešić Živoslav Lj. , Milojković‐Opsenica Dušanka M.
Published: January 2014

High‐performance thin‐layer chromatography (HPTLC) combined with image analysis and pattern recognition methods were used for fingerprinting and classification of 52 propolis samples collected from Serbia and one sample from Croatia. Modern thin‐layer chromatography equipment in combination with software for image processing and warping was applied for fingerprinting and data acquisition. The three mostly used chemometric techniques for classification, principal component analysis, cluster analysis and partial least square‐discriminant analysis, in combination with simple and fast HPTLC method for fingerprint analysis of propolis, were performed in order to favor and encourage their use in planar chromatography. HPTLC fingerprint analysis of propolis was for the first time performed on amino silica plates. All studied propolis samples have been classified in two major types, orange and blue, supporting the idea of existence of two types of European propolis. Signals at specific RF values responsible for classification of studied extracts have also been isolated and underlying compounds targeted for further investigation. Copyright © 2014 John Wiley & Sons, Ltd.
Luminescent Mechanochromic Porous Coordination Polymers
Authors: Wen Tian , Zhou Xiao‐Ping , Zhang De‐Xiang , Li Dan
Published: January 2014

Three 2D luminescent isomeric porous coordination polymers are synthesized and characterized. Their luminescence properties can be modified by grinding and they can act as mechanochromic materials and their properties are probably related to the weak interactions of cuprophilicity and π–π interactions.
Stage‐specific associations between beta blocker use and prognosis after colorectal cancer
Authors: Jansen Lina , Hoffmeister Michael , Arndt Volker , Chang‐Claude Jenny , Brenner Hermann
Published: January 2014

BACKGROUND

Recent observational studies have suggested that the use of beta blockers might be associated with better prognosis after cancer. Because evidence is limited for colorectal cancer (CRC), the association of beta blocker use and prognosis was investigated in a large population‐based cohort of patients with CRC.

METHODS

Between 2003 and 2007, information on beta blocker use at diagnosis and potential confounders was collected by personal interviews for 1975 patients with CRC. Vital status, cause of death, and recurrence status were assessed during a median follow‐up time of 5.0 years. The associations of beta blocker use and overall, CRC‐specific, and recurrence‐free survival were estimated by Cox proportional hazard regression. In addition, beta blocker subgroup, site, and stage‐specific analyses were performed.

RESULTS

After adjustment for covariates including sociodemographic, cancer‐related, and lifestyle factors and comorbidity and medications, no significant association between beta blocker use at diagnosis and prognosis was observed for all stages combined. However, in stage‐specific analyses, beta blocker use was associated with longer overall survival (hazard ratio = 0.50; 95% confidence interval = 0.33‐0.78) and CRC‐specific survival (hazard ratio = 0.47; 95% confidence interval = 0.30‐0.75) in stage IV patients. For these patients, median overall survival was 18 months longer and CRC–specific survival was 17 months longer for beta blocker users than for nonusers (38 versus 20 months and 37 versus 20 months, respectively).

CONCLUSIONS

These results suggest that beta blocker use might be associated with longer survival in patients with stage IV CRC. Cancer 2014;120:1178–1186. © 2014 American Cancer Society.
MTL‐based implementation of current‐mode CMOS RMS‐to‐DC converters
Authors: Shaterian Mostafa , Twigg Christopher M. , Azhari Javad
Published: January 2014

In this paper, systematic implementation of current‐mode RMS‐to‐DC converters based upon MOS translinear (MTL) principle, utilizing symmetric cascoded MTL cell (SCMC) is proposed. Theory of operation and mathematical analysis of both explicit (direct) and implicit (indirect) techniques for realization of SCMC‐based RMS‐to‐DC converters are discussed. The SCMC includes a folded MTL loop and realizes an MTL equation. MTL principle utilizes the square law characteristics of saturated MOS transistors to realize square‐root domain (SRD) functions. The SCMC is constructed by two connected cascoded current mirrors and has a compact, symmetric, and multi‐purpose structure, with capability of implementing the circuits into the programmable and configurable structures. The proposed RMS‐to‐DC converters utilize the SCMC along with a configurable current mirror array. The required squaring and square‐rooting functions are realized using the SCMC, after proper configuration of the current mirror array. The proposed circuits have been implemented using a reconfigurable architecture fabricated in a 0.5 µm CMOS technology. Copyright © 2014 John Wiley & Sons, Ltd.
Endoreduplicative standards for calibration of flow cytometric C‐Value measurements
Authors: Galbraith David W.
Published: January 2014

It has been estimated that there are, globally, as many as 400,000 species of the angiosperms (the flowering plants). Of these, a minimal proportion has been characterized at the cytological level. Urgency is required in initiating a systematic and comprehensive census, due to species extinction as a consequence of anthropogenic activities. Fundamental to eukaryotes is the 2C‐value, the amount of DNA contained within the nucleus of the unreduced gametes. Flow cytometry provides an ideal method for determining C‐values, but the values archived in the Kew Plant C‐value Database represent <2% of these species. Complicating the issue is a proliferation of different, and inconsistent standards for C‐value measurements utilizing flow cytometry, and variability associated with different instrument platforms and using different staining procedures. In previous work, the use of flow cytometry for analysis of plant nuclear DNA contents for species spanning much of the range of genome sizes found in the angiosperms was described. For this work, an endoreduplicative species (Arabidopsis thaliana L.) was particularly helpful as an internal standard for genome size calibration. Such a standard is compromised if it overlaps in DNA content than that of the species whose genome size is sought. This report describes the use of a second species displaying endoreduplication, Capsicum annuum L., for similar standardization. The results (a) indicate accurate reporting of nuclear DNA contents across a range 0.32–423.68 pg, (b) confirm that endoreduplication increases nuclear DNA contents by complete replication of the genome, and (c) provide a means for quality control of linearity in instrumentation over defined dynamic ranges. © 2014 International Society for Advancement of Cytometry
Profit‐based exclusive‐or coding algorithm for data retransmission in DVB‐H with a recovery network
Authors: Wang You‐Chiun
Published: January 2014

The digital video broadcasting‐handheld (DVB‐H) standard is developed by European Telecommunications Standards Institute to broadcast digital videos to handheld devices, but data loss is a critical issue due to the broadcast behavior. On the other hand, DVB‐Internet protocol datacasting (DVB‐IPDC) integrates DVB‐H with an Internet protocol‐based wireless network to provide bidirectional communication. We adopt this wireless network to deal with data retransmission and call it a recovery network. The paper argues that network coding can improve retransmission efficiency of the recovery network because DVB‐H packet loss often exhibits high correlation. In addition, DVB‐H packets may be heterogeneous in the sense that they have different importance. According to these two arguments, the paper considers that DVB‐H packets are associated with different profit depending on their importance and proposes an α‐maximum profit network coding problem. It asks the base station in the recovery network to use no more than α coded packets for handheld devices to retrieve the lost DVB‐H packets such that the overall profit is the maximum. An efficient exclusive‐or coding scheme, namely the profit‐based exclusive‐or network coding (PEN) algorithm, is proposed to solve this problem. Extensive simulation results also verify the effectiveness of the PEN algorithm. Copyright © 2014 John Wiley & Sons, Ltd.
Tosylhydrazide‐Promoted Diastereoselective Intramolecular 1,3‐Dipolar Cycloadditions: Synthesis of Tetrahydropyrrolo[3,4‐c]pyrazoles
Authors: Barroso Raquel , Escribano Maria , Cabal Maria‐Paz , Valdés Carlos
Published: January 2014

A very straightforward diastereoselective synthesis of tetrahydropyrrolo[3,4‐c]pyrazoles by intramolecular 1,3‐dipolar cycloaddition is described. The starting materials for the synthetic route are N‐Boc‐protected α‐amino acids, which are first transformed into N‐allyl‐α‐amino ketones through conventional methodologies. Then, a one‐pot sequence that involves formation of a tosylhydrazone from the ketone, base‐induced decomposition of the hydrazone, and intramolecular 1,3‐dipolar cycloaddition of the diazo compound generated, gives rise to the bicyclic systems with total diastereoselectivity and high preservation of the enantiomeric purity. However, the analogous process employing α‐amino aldehydes lacks stereoselectivity. DFT computational modeling has been carried out to account for the different behavior of the two types of systems.
The isolated carboxy‐terminal domain of human mitochondrial leucyl‐tRNA synthetase rescues the pathological phenotype of mitochondrial tRNA mutations in human cells
Authors: Perli Elena , Giordano Carla , Pisano Annalinda , Montanari Arianna , Campese Antonio F , Reyes Aurelio , Ghezzi Daniele , Nasca Alessia , Tuppen Helen A , Orlandi Maurizia , Di Micco Patrizio , Poser Elena , Taylor Robert W , Colotti Gianni , Francisci Silvia , Morea Veronica , Frontali Laura , Zeviani Massimo , d'Amati Giulia
Published: January 2014

Mitochondrial (mt) diseases are multisystem disorders due to mutations in nuclear or mtDNA genes. Among the latter, more than 50% are located in transfer RNA (tRNA) genes and are responsible for a wide range of syndromes, for which no effective treatment is available at present. We show that three human mt aminoacyl‐tRNA syntethases, namely leucyl‐, valyl‐, and isoleucyl‐tRNA synthetase are able to improve both viability and bioenergetic proficiency of human transmitochondrial cybrid cells carrying pathogenic mutations in the mt‐tRNAIle gene. Importantly, we further demonstrate that the carboxy‐terminal domain of human mt leucyl‐tRNA synthetase is both necessary and sufficient to improve the pathologic phenotype associated either with these “mild” mutations or with the “severe” m.3243A>G mutation in the mt‐tRNALeu(UUR) gene. Furthermore, we provide evidence that this small, non‐catalytic domain is able to directly and specifically interact in vitro with human mt‐tRNALeu(UUR) with high affinity and stability and, with lower affinity, with mt‐tRNAIle. Taken together, our results sustain the hypothesis that the carboxy‐terminal domain of human mt leucyl‐tRNA synthetase can be used to correct mt dysfunctions caused by mt‐tRNA mutations.
Evaluation of the WEPP model and digital elevation grid size, for simulation of streamflow and sediment yield in a heterogeneous catchment
Authors: Pieri Linda , Poggio Matteo , Vignudelli Marco , Bittelli Marco
Published: January 2014

The paper presents the result of an application of the GeoWEPP model in a heterogeneous semi‐agricultural catchment located in the northern Italian Apennines mountain range. The objectives were: (a) to evaluate the GeoWEPP model in a heterogeneous catchment in a Mediterranean climate and (b) to examine the effect of digital elevation model grid size on hydrological and sediment yield simulations. The catchment is characterized by large heterogeneity in geology, soil type, vegetation cover and topography. In addition, 10% of its area is occupied by calanchi (badlands), characterized by steep, bare soil and accentuated erosion. Experimental streamflow data were compared with those simulated by GeoWEPP for a period of eight years and the results were evaluated by means of statistical indices, with the analysis of the flow duration curve. Simulated sediment yields were compared with experimental data for one year. The streamflow cumulative annual results were satisfactory with NSE oscillating between 0.40 and 0.83 and RMSE between 1.1 and 2.9 mm. Also, the performance of the model with daily streamflow data was positive (NSE = 0.68 and RMSE = 1.9 mm). The flow duration curve indicated that GeoWEPP could represent the experimental streamflow for fluxes over 1 mm d−1. The model performance for simulation of sediment yield was satisfactory with both digital elevation models of different grid sizes (NSE = 0.84 and 0.87). Indeed, the sensitivity analysis tests of the model showed that there was no statistically significant improvement in the accuracy of the digital elevation model between 10 and 2 m resolution. These results were confirmed for both streamflow as well as sediment yield. Additional sensitivity analysis of other model parameters performed on the entire catchment and badlands hillslopes showed that bedrock hydraulic conductivity primarily affected the model in both settings. Copyright © 2014 John Wiley & Sons, Ltd.
Kinetic analysis of endothermic degradation of magnesium hydroxide, calcium hydroxide and calcium carbonate in the context of passive fire protection
Authors: Ciudad Aleix , Haurie Laia , Lacasta A. M.
Published: January 2014

In a fire scenario, huge amounts of heat are generated and high temperatures rapidly achieved in such a way that the integrity of structural materials becomes compromised. One of the aims of passive fire protection is the use of building materials that are able to absorb at least part of that heat and maintain the structural materials under critical temperatures for longer times in order to gain evacuation time. Gypsum panels are commonly used in building walls, but they only absorb heat at temperatures around 110 °C. We use three inorganic fillers, Mg(OH)2, Ca(OH)2 and CaCO3, which undergo endothermic transitions at high temperatures to obtain an improved panel with a richer heat‐absorbing profile. With this formulation, the time to reach temperatures of the order of 500 °C, critical for steel and reinforced concrete, is significantly increased. In this work, we focus on the kinetics of the endothermic fillers as an essential ingredient for further spatially extended simulations that include macroscopic heat and mass transfer phenomena or sample heterogeneities. However, kinetics may be affected as well by heat transfer effects that occur at molecular levels. Copyright © 2014 John Wiley & Sons, Ltd.
Recent Advances in Thiol and Sulfide Reactive Probes
Authors: Wang Ke , Peng Hanjing , Wang Binghe
Published: January 2014

Because of the biological relevance of thiols and sulfides such as cysteine, homocysteine, glutathione and hydrogen sulfide, their detection has attracted a great deal of research interest. Fluorescent probes are emerging as a new strategy for thiol and hydrogen sulfide analysis due to their high sensitivity, low cost, and ability to detect and image thiols in biological samples. In this short review, we have summarized recent advances in the development of thiol and hydrogen sulfide reactive fluorescent probes. These probes are compared and contrasted with regard to their designing strategies, mechanisms, photophysical properties, and/or reaction kinetics. Biological applications of these probes are also discussed. J. Cell. Biochem. 115: 1007–1022, 2014. © 2013 Wiley Periodicals, Inc.
Investigating the binding behaviour of two avidin‐based testosterone binders using molecular recognition force spectroscopy
Authors: Rangl Martina , Leitner Michael , Riihimäki Tiina , Lehtonen Soili , Hytönen Vesa P. , Gruber Hermann J. , Kulomaa Markku , Hinterdorfer Peter , Ebner Andreas
Published: January 2014

Molecular recognition force spectroscopy, a biosensing atomic force microscopy technique allows to characterise the dissociation of ligand–receptor complexes at the molecular level. Here, we used molecular recognition force spectroscopy to study the binding capability of recently developed testosterone binders. The two avidin‐based proteins called sbAvd‐1 and sbAvd‐2 are expected to bind both testosterone and biotin but differ in their binding behaviour towards these ligands. To explore the ligand binding and dissociation energy landscape of these proteins, we tethered biotin or testosterone to the atomic force microscopy probe while the testosterone‐binding protein was immobilized on the surface. Repeated formation and rupture of the ligand–receptor complex at different pulling velocities allowed determination of the loading rate dependence of the complex‐rupturing force. In this way, we obtained the molecular dissociation rate (koff) and energy landscape distances (xβ) of the four possible complexes: sbAvd‐1‐biotin, sbAvd‐1‐testosterone, sbAvd‐2‐biotin and sbAvd‐2‐testosterone. It was found that the kinetic off‐rates for both proteins and both ligands are similar. In contrast, the xβ values, as well as the probability of complex formations, varied considerably. In addition, competitive binding experiments with biotin and testosterone in solution differ significantly for the two testosterone‐binding proteins, implying a decreased cross‐reactivity of sbAvd‐2. Unravelling the binding behaviour of the investigated testosterone‐binding proteins is expected to improve their usability for possible sensing applications. Copyright © 2014 John Wiley & Sons, Ltd.
Modeling Multiradicals in Crosslinking MMA/EGDMA Bulk Copolymerization
Authors: Lazzari Stefano , Storti Giuseppe
Published: January 2014

In the present work, a kinetic model of crosslinking free‐radical copolymerization based on multidimensional population balances and accounting for multiradicals is developed. The model is applied to the simulation of bulk copolymerization of methyl‐methacrylate (MMA)/ethylene‐glycol‐dimethacrylate (EGDMA). A literature criterion proposed to elucidate the model type best suited for a given system (i.e., with or without MRs) is extended to the industrially relevant case of diffusion limited systems. Moreover, a master plot for the system under investigation is proposed: given the reaction recipe, the error on the gel point prediction employing the monoradical assumption is identified, thus allowing more conscious model selection.
Crystallization behavior and morphology of β‐nucleated isotactic polypropylene with different stereo‐defect distribution
Authors: Chen Zhengfang , Wang Bin , Kang Jian , Peng Hongmei , Chen Jinyao , Yang Feng , Cao Ya , Li Huilin , Xiang Ming
Published: January 2014

Aiming at further investigating the combination effect of concentration of β‐nucleating agent (β‐NA) and stereo‐defect distribution on the crystallization behavior of β‐nucleated isotactic polypropylene (β‐iPP), in this study, the crystallization behavior and polymorphic morphology of twoβ‐iPP resins with nearly same average isotacticity (PP‐A and PP‐B) but different uniformities of stereo‐defect distribution were investigated by differential scanning calorimetry (DSC), wide angle X‐ray diffraction (WAXD) and polarized optical microscopy (POM). The results of DSC and WAXD showed that the addition of TMB‐5 increases the crystallization temperature and decreases the spherulite sizes of both PP‐A and PP‐B, and reduces their crystallization energy barriers as well; however, the polymorphic behaviors of PP‐A and PP‐B exhibit different dependence on the TMB‐5 concentration. For PP‐A with less uniform distribution of stereo‐defects, β‐phase can be observed only when the TMB‐5 concentration is no less than 0.1 wt.%, while for PP‐B with more uniform stereo‐defect distribution, addition of 0.01 wt.% TMB‐5 can induce the formation of β‐phase. Moreover, the analysis of POM indicated that the crystalline morphologies of both PP‐A and PP‐B change greatly with the TMB‐5 concentration, and the variation features of PP‐A and PP‐B are quite different from each other. PP‐B with more uniform stereo‐defect distribution was more favorable for the formation of large amount of β‐phase in the presence of wide concentration range of TMB‐5. The different polymorphic behaviors and their different dependences on the β‐NA concentration were related to the different uniformities of stereo‐defect distribution of the samples, since the distribution of stereo‐defects could restrain the regular insertion of molecular chains during crystallization and thus determine the tendency the α‐phase crystallization of the sample. Copyright © 2014 John Wiley & Sons, Ltd.
Process influences on the structure, piezoelectric, and gas‐barrier properties of PVDF‐TrFE copolymer
Authors: Oliveira Fabiane , Leterrier Yves , Månson Jan‐Anders , Sereda Olha , Neels Antonia , Dommann Alex , Damjanovic Dragan
Published: January 2014

The influence of annealing between the Curie transition and the melting point of solvent cast polyvinylidene fluoride trifluoroethylene copolymer films on the crystalline structure, mechanical and electrical properties, and oxygen permeability is investigated. Annealing leads to remarkable changes in the structure and properties of the copolymer, within the first four hours of treatment, and with kinetics depending on the temperature. The crystallinity increases by 19% (relative), resulting in a 10 K increase in the Curie transition, a 4 K increase of the melting temperature and a 2 K decrease in the glass transition temperature. A crystalline phase transition from the paraelectric α‐phase to the ferroelectric β‐phase is also evidenced using in‐situ X‐ray diffraction. The elastic modulus is found to increase by more than three‐fold at room temperature and the loss peak at the glass transition is considerably reduced. The piezoelectric coefficient is found to increase by 40% and the dielectric properties are significantly changed. The most remarkable influence is the ten‐fold reduction of the oxygen permeability, with a drastic reduction of the activation energy for oxygen transport. The improvement in oxygen barrier properties of the annealed copolymer is attributed to the restricted mobility of oxygen molecules in the semicrystalline polymer with nanometer sized crystallites. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014, 52, 496–506
E‐loyalty towards a cancer information website: applying a theoretical framework
Authors: Crutzen Rik , Beekers Nienke , van Eenbergen Mies , Becker Monique , Jongen Lilian , van Osch Liesbeth
Published: January 2014

Objective

To provide more insight into user perceptions related to e‐loyalty towards a cancer information website. This is needed to assure adequate provision of high quality information during the full process of cancer treatment—from diagnosis to after care—and an important first step towards optimizing cancer information websites in order to promote e‐loyalty.

Methods

Participants were cancer patients (n = 63) and informal caregivers (n = 202) that visited a website providing regional information about cancer care for all types of cancer. Subsequently, they filled out a questionnaire assessing e‐loyalty towards the website and user perceptions (efficiency, effectiveness, active trust and enjoyment) based on a theoretical framework derived from the field of e‐commerce. A structural equation model was constructed to test the relationships between user perceptions and e‐loyalty.

Results

Participants in general could find the information they were looking for (efficiency), thought it was relevant (effectiveness) and that they could act upon it (active trust) and thought the visit itself was pleasant (enjoyment). Effectiveness and enjoyment were both positively related with e‐loyalty, but this was mediated by active trust. Efficiency was positively related with e‐loyalty. The explained variance of e‐loyalty was high (R2 = 0.70).

Conclusions

This study demonstrates that the importance of user perceptions is not limited to fields such as e‐commerce but is also present within the context of cancer information websites. The high information need among participants might explain the positive relationship between efficiency and e‐loyalty. Therefore, cancer information websites need to foster easy search and access of information provided. Copyright © 2014 John Wiley & Sons, Ltd.
Comparative proteomic analysis of malignant pleural mesothelioma evidences an altered expression of nuclear lamin and filament‐related proteins
Authors: Giusti Laura , Da Valle Ylenia , Bonotti Alessandra , Donadio Elena , Ciregia Federica , Ventroni Tiziana , Foddis Rudy , Giannaccini Gino , Guglielmi Giovanni , Cristaudo Alfonso , Lucacchini Antonio
Published: January 2014

Purpose

Malignant mesothelioma is a neoplastic disease linked to asbestos exposure whose diagnosis is limited, so detection methods for an early diagnosis and treatment result essential. Here, we compared proteomic profiles of malignant pleural mesothelioma (MPM) and benign biopsies to search potential biomarkers useful in differential diagnosis.

Experimental design

Tissue biopsies were obtained from 53 patients who were subjected to a diagnostic thoracoscopy. 2DE/MS based approach was used for proteomic analysis and protein validation was carried out by Western blot analysis versus benign and lung carcinoma samples.

Results

Among the proteins identified we confirmed known MPM biomarkers such as calretinin and suggested the new ones as prelamin A/C, desmin, vimentin, calretinin, fructose‐bisphosphate aldolase A, myosin regulatory light chain 2, ventricular/cardiac muscle isoform, myosin light chain 3 and myosin light chain 6B. Ingenuity software was used to identify the biological processes to which these proteins belong and to construct a potential network.

Conclusions and clinical relevance

Overall, our results suggest potential biomarkers that can be useful in occupational medicine for the early identification of the onset of disease in health surveillance of past asbestos‐exposed workers, for monitoring the progress of disease and for assessing the response to treatment.
The improved piezoelectric properties of ZnO nanorods with oxygen plasma treatment on the single layer graphene coated polymer substrate
Authors: Hussain Mushtaque , Abbasi Mazhar Ali , Ibupoto Zafar Hussain , Nur Omer , Willander Magnus
Published: January 2014

The step towards the fabrication of nanodevices with improved performance is of high demand; therefore, in this study, oxygen plasma treated ZnO nanorods based piezoelectric nanogenerator is developed on the single layer graphene coated PET flexible polymer substrate. ZnO nanorods on the single layer graphene are grown by hydrothermal growth method and the structural study is carried out by using X‐ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The piezoelectric properties of ZnO nanorods with and without plasma treatment were investigated by atomic force microscopy (AFM). The oxygen plasma treated sample of ZnO nanorods showed significant increase in the piezoelectric potential which could be due to the decrease in the defects levels in the ZnO and also increase in the mechanical properties of ZnO nanorods. Furthermore X‐ray photoelectron spectroscopy (XPS) confirms that the filling of vacancies by oxygen in the matrix of ZnO using oxygen plasma treatment has gave an enhanced piezoelectric potential compared to the sample of ZnO nanorods not treated with oxygen plasma. In addition to XPS experiment, cathodoluminescence (CL) technique was used for the determination of defect level in the ZnO nanorods after the treatment of oxygen plasma and the obtained information supported the XPS data of oxygen plasma treatment sample by showing the decreased level of defect levels in the prepared sample. From the XPS and CL studies, it is observed that the defect level has significant influence on the piezoelectric potential of the ZnO nanostructures.
Frequent sub‐graph mining for intelligent malware detection
Authors: Eskandari Mojtaba , Raesi Hooman
Published: January 2014

Malware is a serious threat that has caused catastrophic disasters in recent decades. To deal with this issue, various approaches have been proposed. One effective and widely used method is signature‐based detection. However, there is a substantial problem in detecting new instances; therefore, this method is solely useful for second malware attacks. In addition, owing to the rapid proliferation of malware and the significant human effort requirement to extract signatures, this approach is an inadequate solution; thus, an intelligent malware detection system is required. One of the major phases of such a system is feature extraction, used to construct a learning model. This paper introduces an approach to generate a group of semantic signatures, represented by a set of learning models, in which various features indicate the different programming styles of the execution files. A set of these signatures is obtained by mining frequent sub‐graphs, common code sub‐structures employed for malware writing, in a group of control flow graphs. The experimental results depict an improved F‐measure rate in comparison with the classic graph‐based approach. Copyright © 2014 John Wiley & Sons, Ltd.
Trust computation for multiple routes recommendation in social network sites
Authors: Zhang Bo , Huang Zhenhua , Yu Jian , Xiang Yang
Published: January 2014

Nowadays, social network site (SNS) has been a popular platform for information sharing and dissemination. However, because of unknown information sources or unfamiliar recommenders, users of SNS may receive thousands of recommending information, which contain potential risks to receivers. To meet the challenge of confirming reliabilities of recommendations, a novel method of recommended trust computation is proposed in this paper. Firstly, according to the elements of users' relationships and community characteristics in SNS, concepts of belief and reputation are defined to express subjective trustable relationship among individuals and objective trust view. Then, recommended trust computation is presented on the basis of aforementioned two concepts. The recommended trust computation is divided into two aspects, that is, recommended trust computation with different route composition and recommendation optional confidence. Further, a SNS recommended trust computation framework is proposed. Finally, examinations are given to further explain the efficiency and feasibility of our mechanism. Copyright © 2014 John Wiley & Sons, Ltd.
Choosing profile double‐sampling designs for survival estimation with application to President's Emergency Plan for AIDS Relief evaluation
Authors: An Ming‐Wen , Frangakis Constantine E. , Yiannoutsos Constantin T.
Published: January 2014

Most studies that follow subjects over time are challenged by having some subjects who dropout. Double sampling is a design that selects and devotes resources to intensively pursue and find a subset of these dropouts, then uses data obtained from these to adjust naïve estimates, which are potentially biased by the dropout. Existing methods to estimate survival from double sampling assume a random sample. In limited‐resource settings, however, generating accurate estimates using a minimum of resources is important. We propose using double‐sampling designs that oversample certain profiles of dropouts as more efficient alternatives to random designs. First, we develop a framework to estimate the survival function under these profile double‐sampling designs. We then derive the precision of these designs as a function of the rule for selecting different profiles, in order to identify more efficient designs. We illustrate using data from the United States President's Emergency Plan for AIDS Relief‐funded HIV care and treatment program in western Kenya. Our results show why and how more efficient designs should oversample patients with shorter dropout times. Further, our work suggests generalizable practice for more efficient double‐sampling designs, which can help maximize efficiency in resource‐limited settings. Copyright © 2014 John Wiley & Sons, Ltd.
Synthesis and Surface Properties of Anionic Gemini Surfactants having N‐acylamide and Carboxylate Groups
Authors: Zhou Yan , Cheng Yun , Han Chunyu , Lai Junling , Sui Lin , Luo Genxiang
Published: January 2014

A straightforward synthetic strategy to an anionic gemini surfactant having both N‐acylamide and carboxylate groups in a molecule has been demonstrated. The surface properties of the anionic gemini surfactant, such as CMC (critical micelle concentration), C20 (the concentration required to reduce the surface tension of the solvent by 20 mN/m), γCMC (the surface tension at the CMC), ∏CMC (the surface pressure at the CMC), Γmax (the maximum surface excess concentration at the air/aqueous solution interface), Amin (the minimum area per surfactant molecule at the air/water interface), and the CMC/C20 ratio (a measure of the tendency to form micelles relative to adsorbtion at the air/water interface), have been studied. The influence of the different concentrations of NaCl on the surface properties of the gemini surfactant has been discussed. The results have shown that the CMC values decreased with an increase in the concentration of NaCl indicating that the Na+ preferentially adsorbs onto the surface of the charged aggregate and facilitates the aggregate growth by suppressing the main impediment of electrostatic repulsion among head groups. Additionally, the values of Γmax are always higher in salt solutions as compared to those in pure water due to their salting out effect. The larger pC20 value indicates that the surfactant adsorbs more efficiently at the air/water interface and reduces surface tension more efficiently. In addition, the geminis in water show little or no break in their specific conductance versus surfactant molar concentration plots. This is attributable to protonation of the carboxylate group and strong Na+ release during micellization.
The prevalence of mild cognitive impairment and its etiological subtypes in elderly Chinese
Authors: Jia Jianping , Zhou Aihong , Wei Cuibai , Jia Xiangfei , Wang Fen , Li Fang , Wu Xiaoguang , Mok Vincent , Gauthier Serge , Tang Muni , Chu Lan , Zhou Youlong , Zhou Chunkui , Cui Yong , Wang Qi , Wang Weishan , Yin Peng , Hu Nan , Zuo Xiumei , Song Haiqing , Qin Wei , Wu Liyong , Li Dan , Jia Longfei , Song Juexian , Han Ying , Xing Yi , Yang Peijie , Li Yuemei , Qiao Yuchen , Tang Yi , Lv Jihui , Dong Xiumin
Published: January 2014

Background

Epidemiologic studies on mild cognitive impairment (MCI) are limited in China.

Methods

Using a multistage cluster sampling design, a total of 10,276 community residents (6096 urban, 4180 rural) aged 65 years or older were evaluated and diagnosed with normal cognition, MCI, or dementia. MCI was further categorized by imaging into MCI caused by prodromal Alzheimer's disease (MCI‐A), MCI resulting from cerebrovascular disease (MCI‐CVD), MCI with vascular risk factors (MCI‐VRF), and MCI caused by other diseases (MCI‐O).

Results

The prevalences of overall MCI, MCI‐A, MCI‐CVD, MCI‐VRF, and MCI‐O were 20.8% (95% confidence interval [CI] = 20.0–21.6%), 6.1% (95% CI = 5.7–6.6%), 3.8% (95% CI = 3.4–4.2%), 4.9% (95% CI = 4.5–5.4%), and 5.9% (95% CI = 5.5–6.4%) respectively. The rural population had a higher prevalence of overall MCI (23.4% vs 16.8%, P < .001).

Conclusions

The prevalence of MCI in elderly Chinese is higher in rural than in urban areas. Vascular‐related MCI (MCI‐CVD and MCI‐VRF) was most common.
Serial position effects are sensitive predictors of conversion from MCI to Alzheimer's disease dementia
Authors: Egli Simone C. , Beck Irene R. , Berres Manfred , Foldi Nancy S. , Monsch Andreas U. , Sollberger Marc
Published: January 2014

Background

It is unclear whether the predictive strength of established cognitive variables for progression to Alzheimer's disease (AD) dementia from mild cognitive impairment (MCI) varies depending on time to conversion. We investigated which cognitive variables were best predictors, and which of these variables remained predictive for patients with longer times to conversion.

Methods

Seventy‐five participants with MCI were assessed on measures of learning, memory, language, and executive function. Relative predictive strengths of these measures were analyzed using Cox regression models.

Results

Measures of word‐list position—namely, serial position scores—together with Short Delay Free Recall of word‐list learning best predicted conversion to AD dementia. However, only serial position scores predicted those participants with longer time to conversion.

Conclusions

Results emphasize that the predictive strength of cognitive variables varies depending on time to conversion to dementia. Moreover, finer measures of learning captured by serial position scores were the most sensitive predictors of AD dementia.
Comparison of Heat Donation Through the Head or Torso on Mild Hypothermia Rewarming
Authors: Sran Bhupinder Jit K. , McDonald Gerren K. , Steinman Alan M. , Gardiner Phillip F. , Giesbrecht Gordon G.
Published: January 2014

Objective

The purpose of the study was to compare the effectiveness of head vs torso warming in rewarming mildly hypothermic, vigorously shivering subjects using a similar source of heat donation.

Methods

Six subjects (1 female) were cooled on 3 occasions in 8°C water for 60 minutes or to a core temperature of 35°C. They were then dried, insulated, and rewarmed by 1) shivering only; 2) charcoal heater applied to the head; or 3) charcoal heater applied to the torso. The order of rewarming methods followed a balanced design. Esophageal temperature, skin temperature, heart rate, oxygen consumption, and heat flux were measured.

Results

There were no significant differences in rewarming rate among the 3 conditions. Torso warming increased skin temperature and inhibited shivering heat production, thus providing similar net heat gain (268 ± 66 W) as did shivering only (355 ± 105 W). Head warming did not inhibit average shivering heat production (290 ± 72 W); it thus provided a greater net heat gain during 35 to 60 minutes of rewarming than did shivering only.

Conclusions

Head warming is as effective as torso warming for rewarming mildly hypothermic victims. Head warming may be the preferred method of rewarming in the field management of hypothermic patients if: 1) extreme conditions in which removal of the insulation and exposure of the torso to the cold is contraindicated; 2) excessive movement is contraindicated (eg, potential spinal injury or severe hypothermia that has a risk of ventricular fibrillation); or 3) if emergency personnel are working on the torso.