bluuebunny/crossref_metadata_2025 huggingface dataset:
Confronting species distribution model predictions with species functional traits
Authors: Wittmann Marion E. , Barnes Matthew A. , Jerde Christopher L. , Jones Lisa A. , Lodge David M.
Published: February 2016

Species distribution models are valuable tools in studies of biogeography, ecology, and climate change and have been used to inform conservation and ecosystem management. However, species distribution models typically incorporate only climatic variables and species presence data. Model development or validation rarely considers functional components of species traits or other types of biological data. We implemented a species distribution model (Maxent) to predict global climate habitat suitability for Grass Carp (Ctenopharyngodon idella). We then tested the relationship between the degree of climate habitat suitability predicted by Maxent and the individual growth rates of both wild (N = 17) and stocked (N = 51) Grass Carp populations using correlation analysis. The Grass Carp Maxent model accurately reflected the global occurrence data (AUC = 0.904). Observations of Grass Carp growth rate covered six continents and ranged from 0.19 to 20.1 g day−1. Species distribution model predictions were correlated (r = 0.5, 95%CI(0.03, 0.79)) with observed growth rates for wild Grass Carp populations but were not correlated (r = −0.26, 95%CI(−0.5, 0.012)) with stocked populations. Further, a review of the literature indicates that the few studies for other species that have previously assessed the relationship between the degree of predicted climate habitat suitability and species functional traits have also discovered significant relationships. Thus, species distribution models may provide inferences beyond just where a species may occur, providing a useful tool to understand the linkage between species distributions and underlying biological mechanisms.
Synthesis of Vanadium‐Incorporated, Polyoxometalate‐Based Open Frameworks and Their Applications for Cathode‐Active Materials
Authors: Zhang Zhenxin , Yoshikawa Hirofumi , Zhang Zhongyue , Murayama Toru , Sadakane Masahiro , Inoue Yasunori , Ueda Wataru , Awaga Kunio , Hara Michikazu
Published: February 2016

The tuning of the chemical composition of polyoxometalate (POM)‐based open framework materials with the same structure, leading to a property change of the materials, is interesting. Here, we report the synthesis of a series of vanadium‐incorporated, ϵ‐Keggin polyoxometalate‐based open framework materials by using a hydrothermal method. The resulting materials were characterized by powder X‐ray diffraction, FTIR spectroscopy, scanning electron microscopy, energy dispersive X‐ray spectroscopy, X‐ray photoelectron spectroscopy, and elemental analysis. Our results indicate that V is successfully incorporated into the frameworks of the materials. The introduced amount of V can be adjusted by controlling the addition of the precursor V compounds. The performances of these materials as cathode materials for Li‐ion batteries have been tested. Incorporation of V can improve the cycle performance. After the 20th cycle of the charge–discharge process, the materials were transformed to the Li2MoO4 phase.
On the Stability of Trimeric Beryllium Hydroxide Scorpionate Complexes
Authors: Naglav Dominik , Tobey Briac , Wölper Christoph , Bläser Dieter , Jansen Georg , Schulz Stephan
Published: February 2016

The controlled hydrolysis of TpBeCl {Tp = trispyrazolylborate [HB(C3N2H3)3]–} with H2O and D2O in the presence of N,N‐diisopropylethylamine (DIPEA) yields the trimeric beryllium hydroxide scorpionate complexes [Be3(µ‐OX)3(Tp)3] (X = H: 1, D: 2) quantitatively. The complexes contain six‐membered Be3O3 rings according to single‐crystal X‐ray diffraction studies and theoretical calculations. Temperature‐dependent 1H and 9Be NMR spectroscopy established that 1 has a dynamic structure in solution. In addition, the structure of [Be3(µ‐OH)3(Br)3(thf)6], which was obtained from hydrolysis of a solution of BeBr2 in tetrahydrofuran and CHCl3, is reported.
RhIII‐Catalyzed C–H Allylation of Amides and Domino Cycling Synthesis of 3,4‐Dihydroisoquinolin‐1(2H)‐ones with N‐Bromosuccinimide
Authors: Dai Huimin , Yu Chao , Lu Changsheng , Yan Hong
Published: February 2016

A RhIII‐catalyzed C–H allylation of electron‐deficient arenes, heteroarenes, and alkenes at room temperature was developed with allyl bromide. The reaction was carried out in diethyl ether without dehydration, and C–H activation was assisted by the directing anionic nitrogen of the aniline‐derived amide. Following the allylation, a domino cycling synthesis of 3,4‐dihydroisoquinolin‐1(2H)‐ones with N‐bromosuccinimide (NBS) through intramolecular aminobromination of the introduced double bond was achieved.
Lipase‐catalyzed esterification of konjac glucomannan in isooctane
Authors: XiaoYan Long , JiuXiang Pan , LinQiu Yao
Published: February 2016

Konjac glucomannan (KGM) is an abundant natural polysaccharide that is renewable and fully biodegradable. Modification of KGM OH groups by esterification to form an appropriate degree of substitution (DS) imparts rheological property and water resistance to the KGM ester over the unmodified KGM. Chemical reaction catalyzed by enzyme is an environmentally friendly method which occurs under milder reaction condition. Lipase (Novozym 435) was used to catalyze the esterification reaction between oleic acid and KGM in isooctane. The DS of the esterified KGM was used to evaluate the extent of esterification. Five variables (water activity, reaction temperature, the ratio of oleic acid and KGM, phosphate buffer content, and reaction time) were investigated to optimize the experimental conditions of the KGM oleate synthesis. The optimal conditions for a DS of 0.370 are phosphate buffer solution 2.0% (v/v), a KGM/oleic acid weight ratio of 3 during 36 h of shaking at 55°C in isooctane. Phosphate buffer solution content of the reaction system played a key role in the esterification of KGM in isooctane. The structure of the modified KGM was checked by IR, fluorescence spectra, XRD, thermogravimetric analysis, and rheology. Results showed that hydrophobicity and hydrophilicity of KGM was significantly affected after esterification. The KGM fatty acid esters produced may have potential applications such as humidity‐sensitive coating and hydrophobic drug delivery. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 1149–1155, 2016
Secrecy performance of MIMO Nakagami‐m wiretap channels with optimal TAS and different antenna schemes
Authors: da Costa Daniel Benevides , Ferdinand Nuwan Suresh , Dias Ugo Silva , de Sousa Rafael Timóteo , Latva‐aho Matti
Published: February 2016

Transmit antenna selection (TAS) in wiretap channels has arisen as a simple promising scheme to improve physical layer security. However, up to now, TAS schemes have aimed at maximising the instantaneous signal‐to‐noise ratio of the legitimate receiver, which by its essence is a sub‐optimal strategy from a secrecy point of view. In this paper, unlike previous works, we propose a novel TAS scheme for multiple‐input multiple‐output wiretap channels by exploiting full channel state information. The proposed scheme achieves higher secrecy performance by selecting an antenna that maximises the secrecy rate. In our analysis, we assume that the receiver (Rx) and the eavesdropper employ either selection combining (SC) or maximal‐ratio combining (MRC) to combine the received signals, and this results in four different receiver combining arrangements. By considering Nakagami‐m fading, secrecy performance is analysed. Specifically, closed‐form expressions for the secrecy outage probability are derived, which can be used as a quality of service metric. Moreover, an asymptotic analysis is carried out and the respective diversity/array gains are obtained. The ergodic secrecy rate is also investigated for the case of multiple‐input single‐output wiretap channels. Insightful discussions are attained from our analysis. For instance, it is shown that the performance gain of MRC over SC at the Rx does not depend on the number of antennas and combining scheme at the eavesdropper. More interestingly, we observe that such a performance gain is independent of the TAS scheme used at the transmitter (Tx). On the other hand, it is shown that the secrecy gap between SC and MRC at the eavesdropper is independent of the number of antennas at the Tx, but it depends on the number of antennas at the Rx. Finally, it is demonstrated that the diversity gain is the same for all antenna configurations. Copyright © 2016 John Wiley & Sons, Ltd.
Location and the Global Advantage of Firms
Authors: Mesquita Luiz F.
Published: February 2016

The goal of this article is to point to a research agenda framing the internationalization of firms on theories of location—which is defined as positions of place, time, and space that engender tacit sources of competitive advantage. Despite recent research merging location and internationalization theoretical models, much remains unknown, and future work is warranted to respond to four fundamental questions: (1) why firms venture abroad; (2) how such motivations shape FDI patterns; (3) how multinational firms shape the foreign environments they enter; and (4) what resources and (dynamic) capabilities are involved in such a process. The specific contributions of the articles to the research agenda are also highlighted here. Copyright © 2016 Strategic Management Society.
Wild Bootstrap Inference for Wildly Different Cluster Sizes
Authors: MacKinnon James G. , Webb Matthew D.
Published: February 2016

The cluster robust variance estimator (CRVE) relies on the number of clusters being sufficiently large. Monte Carlo evidence suggests that the ‘rule of 42’ is not true for unbalanced clusters. Rejection frequencies are higher for datasets with 50 clusters proportional to US state populations than with 50 balanced clusters. Using critical values based on the wild cluster bootstrap performs much better. However, this procedure fails when a small number of clusters is treated. We explain why CRVE t statistics and the wild bootstrap fail in this case, study the ‘effective number’ of clusters and simulate placebo laws with dummy variable regressors. Copyright © 2016 John Wiley & Sons, Ltd.
Skin and muscle permeating antibacterial nanoparticles for treating Staphylococcus aureus infected wounds
Authors: Dhanalakshmi V. , Nimal T. R. , Sabitha M. , Biswas Raja , Jayakumar R.
Published: February 2016

Majority of the chronic wounds are infected with bacteria like Staphylococcus aureus (S. aureus). The deep tissue infections are difficult to treat using topical antibiotics, due to their poor tissue penetration. In order to treat S. aureus deep tissue infections we have developed an antibiotic delivery system using chitosan nanoparticles (CNPs). To enhance their tissue penetration these CNPs were further coated using lecithin (CLNPs). Antibiotic tigecycline was loaded into chitosan nanoparticles (tCNPs) and then coated with lecithin to generate lecithin coated tigecycline loaded chitosan nanoparticles (tCLNPs). The prepared nanoparticles were characterized using DLS, SEM, TEM and FT‐IR. The prepared CNPs, tCNPs, CLNPs and tCLNPs have the size range of 85 ± 10, 90 ± 18, 188 ± 5 and 235 ± 20 nm, respectively. The tCLNPs shows more sustained release pattern of tigecycline. The antibacterial activity of the developed nanoparticles was confirmed against laboratory and clinical strains of S. aureus using in vitro and ex vivo experiments. The ex vivo skin and muscle permeation study ensures the enhanced delivery of tigecycline to the deeper tissue. The prepared nanoparticles were hemo‐compatible and cyto‐compatible. Our study suggests that the prepared tCLNPs can be effectively used for the treatment of S. aureus infected wounds. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 797–807, 2016.
Fabrication of Hexagonal Boron Nitride Nanosheets by Using a Simple Thermal Exfoliation Process
Authors: Ko Wen‐Yin , Chen Cheng‐Yu , Chen Wei‐Hung , Lin Kuan‐Jiuh
Published: February 2016

A simple and inexpensive method to exfoliate boron nitride powder to form boron nitride nanosheets (BNNSs) with few layers was achieved by using a physically thermal process. The obtained BNNSs were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), atomic force microscopy (AFM), X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), IR spectroscopy, and Raman spectroscopy. The size distribution of the sheets and average sheet size is in the range of 80–380 nm and 200±62 nm, respectively, and the pure phase h‐BN products were confirmed. XPS result showed the B/N atomic ratio to be 0.99. In addition, the BNNSs can well disperse in aqueous solution to form a cloudy suspension and importantly, can remain suspended for 1 month without precipitate, which would have good potential in a wide range of applications.
DFT Study of Carbon Crystals from Nested K4 Lattice to BC‐8 Structure
Authors: Hagita Katsumi , Sahara Ryoji , Kawazoe Yoshiyuki
Published: February 2016

Carbon crystals of a nested K4 lattice and BC‐8 structure are studied. We propose a unified relationship between the nested K4 lattice and the BC‐8 structure. The atomic positons of both structures can be given by Wyckoff position 16(c) of space group No. 206 and its shifted lattice. We can obtain continuously changing configurations from the nested K4 lattice to the BC‐8 structure with one parameter. DFT calculation based on plane waves is performed in order to estimate the total energy and phonon DOS. The structure near the BC‐8 structure is found to have a stable state. We consider the nested K4 lattice a saddle point on the energy landscape and it is in a metastable state.
Synthesis of ZnO Nanoparticles Based on Zn Complex Achieved from L‐leucine
Authors: Gharagozlou Mehrnaz , Naghibi Sanaz
Published: February 2016

In the present study, ZnO nanoparticle preparation in a water‐base medium without using toxic chemicals was investigated. Zinc (II) acetate dehydrate, Lleucine and 5sulfosalicylaldehyde sodium salt were utilized as the starting materials. Xray diffraction analyses proved that ZnO was achieved as a unique phase. The highest value of crystallinity was obtained at 600 °C and the minimum values of crystallite size and lattice strain were reported at 400 and 500 °C, respectively. The photoluminescence spectroscopy showed that firing at 500 °C leads to decrease the point defects in ZnO structure. SEM and TEM images confirmed the relation between the firing temperature, the degree of crystallinity and the crystallite size. Firing at 400 °C leads to form ZnO nanoparticles with a size distribution ranging from 15 to 50 nm with cubic, circle and hexagonal shapes. By increasing the temperature to 500 °C, the nanoparticles dimensions increase to 30–60 nm. The particle size of sample ‘c’ is more than 50 nm. The optimum temperature to achieve the goal of this research, namely a high crystallinity and low structure defects, was found to be 500 °C.
Clinical Value of Hypochromia Markers in the Detection of Latent Iron Deficiency in Nonanemic Premenopausal Women
Authors: Urrechaga Eloísa , Borque Luís , Escanero Jesús F.
Published: February 2016

Background

Iron deficiency (ID) is the most common cause of anemia in fertile women and hemoglobin (Hb) within the reference interval does not exclude ID. The consequence of an imbalance between the iron requirements and supply is a reduction of red‐cell Hb content, which causes hypochromic cells. The aim of this study was to assess the reliability of new parameters low Hb density (LHD%), reticulocyte Hb equivalent (RetHe), and percentage of hypochromic erythrocytes (%HypoHe) in the detection of latent ID (LID), defined as depletion of iron stores without anemia.

Methods

Two hundred fifty consecutive nonanemic women in fertile age (18–40 years, mean 33.5 years), whose analyses had been requested by general practitioners, were included. Independent samples t‐test, receiver operating characteristic (ROC) curve analysis (gold standard for detecting LID ferritin <30 μg/l), and Cohen's kappa index were applied.

Results

One hundred fifty‐three women had ferritin within the reference range and Hb >120 g/L; 97 (38.8%) had LID. The results were as follows: %HypoHe—AUC 0.934, cutoff 1.6%, sensitivity 85.7%, specificity 92.1%; RetHe—AUC 0.914, cutoff 29.9 pg, sensitivity 86.8%, specificity 85.7%; LHD%—AUC 0.898, cutoff 5.0%, sensitivity 85.9%, specificity 84.1%. Applying those cutoffs, agreement between ferritin and %HypoHe was κ 0.61 and 0.56 for RetHe and LHD%.

Conclusions

LHD%, %HypoHe, and RetHe emerge as reliable tests for the investigation of LID and could improve the ability to detect ID before anemia is present.
Meaning Making in the Context of Disasters
Authors: Park Crystal L.
Published: February 2016

Objective

Understanding the factors underlying adaptive psychological responses and recovery after disasters has important implications for intervention and prevention efforts. To date, little attention has been paid to successful coping processes in recovering from natural and technological disasters. This article takes a meaning making perspective to explicate how survivors successfully adapt after disasters.

Method

Relevant literature is reviewed to illustrate the process of adaptation and resilience after disasters.

Results

Studies to date suggest both survivors’ global meaning, particularly their religiousness and sense of meaning, and their appraisals and meaning making after the disaster are important influences on their postdisaster resilience. Meanings made in the form of changes in global beliefs and perceived growth have been reported and shown to have inconsistent relations with adjustment.

Conclusions

Although much more research is needed, current literature suggests that meaning making processes are central to recovery and resilience after a range of disasters.
Response Surface Analysis and Nonlinear Optimization Algorithm for Maximization of Clinical Drug Performance: Application to Extended‐Release and Long‐Acting Injectable Paliperidone
Authors: Gomeni Roberto , Bressolle‐Gomeni Françoise , Fava Maurizio
Published: February 2016

Model‐based approach is recognized as a tool to make drug development more productive and to better support regulatory and therapeutic decisions. The objective of this study was to develop a novel model‐based methodology based on the response surface analysis and a nonlinear optimizer algorithm to maximize the clinical performances of drug treatments. The treatment response was described using a drug‐disease model accounting for multiple components such as the dosage regimen, the pharmacokinetic characteristics of a drug (including the mechanism and the rate of drug delivery), and the exposure‐response relationship. Then, the clinical benefit of a treatment was defined as a function of the diseases and the clinical endpoints and was estimated as a function of the target pharmacodynamic endpoints used to evaluate the treatment effect. A case study is presented to illustrate how the treatment performances of paliperidone extended release (ER) and paliperidone long‐acting injectable (LAI) can be improved. A convolution‐based approach was used to characterize the pharmacokinetics of ER and LAI paliperidone. The drug delivery properties and the dosage regimen maximizing the clinical benefit (defined as the target level of D2 receptor occupancy) were estimated using a nonlinear optimizer. The results of the analysis indicated that a substantial improvement in clinical benefit (from 15% to 27% for the optimization of the in vivo release and from ∼30% to ∼70% for the optimization of dosage regimen) was obtained when optimal strategies were deployed either for optimizing the in vivo drug delivery properties of ER formulations or for optimizing the dosage regimen of LAI formulations.
A Clinical Study Evaluating the Effects of Fluvastatin on Serum Osteoprotegerin Levels in Rheumatoid Arthritis Patients
Authors: Hegazy Sahar Kamal , El‐Ghany El‐Sayed Salwa El‐Morsy Abd , El‐Hefnawy Marwa El‐Saeed
Published: February 2016

Osteoprotegerin (OPG), a member of the tumor necrosis factor receptor family, has been identified as a critical regulator of bone resorption. Considering the possible role of OPG in rheumatoid arthritis (RA) and in the osteoclastogenesis suppression effects of statins, the present study aims to investigate the effects of fluvastatin on serum levels OPG and disease activity score (DAS) in patients with RA. Forty patients with RA were randomized in a placebo‐controlled trial to receive 40 mg fluvastatin or placebo as an adjunct to existing disease‐modifying antirheumatic drug (DMARD) therapy (methotrexate, leflunomide, hydroxychloroquine). Patients were followed up over 12 weeks. OPG and disease activity variables were measured at baseline and after 12 weeks of treatment. After 12 weeks, the OPG level was significantly increased in the fluvastatin group compared to the placebo group. DAS‐28 was significantly decreased in the fluvastatin group compared to the placebo group. C‐reactive protein (CRP), morning stiffness, swollen joint count (SJC), and tender joint count (TJC) were significantly decreased in the fluvastatin group compared to the placebo group; however, erythrocyte sedimentation rate (ESR), modified health assessment questionnaire (MHAQ), and visual analogue screen (VAS) were not changed significantly. In conclusion, fluvastatin administration could increase the OPG levels and improve disease activity variables in patients with RA. Therefore, fluvastatin may serve a potential benefit in the treatment of RA patients.
The Maximum Number of Complete Subgraphs of Fixed Size in a Graph with Given Maximum Degree
Authors: Cutler Jonathan , Radcliffe A. J.
Published: February 2016

In this article, we make progress on a question related to one of Galvin that has attracted substantial attention recently. The question is that of determining among all graphs G with n vertices and , which has the most complete subgraphs of size t, for . The conjectured extremal graph is , where with . Gan et al. (Combin Probab Comput 24(3) (2015), 521–527) proved the conjecture when , and also reduced the general conjecture to the case . We prove the conjecture for and also establish a weaker form of the conjecture for all r.
Association of the apparent diffusion coefficient with maturity in adolescent sacroiliac joints
Authors: Bray Timothy J.P. , Vendhan Kanimozhi , Roberts James , Atkinson David , Punwani Shonit , Sen Debajit , Ioannou Yiannis , Hall‐Craggs Margaret A.
Published: February 2016

Purpose

To determine the extent to which apparent diffusion coefficient (ADC) values vary with skeletal maturity in adolescent joints.

Materials and Methods

A retrospective study was performed with Institutional Review Board (IRB) approval. We used a picture archiving and communication system (PACS) search to identify and recruit all adolescents who had undergone 1.5T magnetic resonance imaging (MRI) of the sacroiliac joints (SIJs) between January 2010 and June 2015, and had no evidence of sacroiliitis and normal inflammatory markers. In all, 55 individuals were assessed. For each patient, coronal and sagittal images of the sacrum were visually analyzed to determine sacral maturity. Patients were divided into three groups depending on the degree of fusion of the sacral segmental apophyses: “Fused,” “Partial,” and “Unfused.” For each group, SIJ ADC was measured using a linear region‐of‐interest technique.

Results

Mean ADC values were 690 × 10−6 mm2/s in the fused group, 720 × 10−6 mm2/s in the partial group, and 842 × 10−6 mm2/s in the unfused group. ADC values were significantly higher in the unfused group than in the fused group (P = 0.046). ADC values were also higher in unfused subjects than partially fused subjects (P = 0.074).

Conclusion

Joint ADC values are higher in skeletally immature (unfused) patients than in skeletally more mature (fused) patients. ADC values measured in the unfused group overlap with those previously reported in sacroiliitis. These results suggest that ADC measurements in adolescent joints must be interpreted in light of joint maturity. Joint immaturity may lead to misdiagnosis of sacroiliitis, since immature juxta‐articular bone may appear similar to inflammation. J. Magn. Reson. Imaging 2016. J. Magn. Reson. Imaging 2016;44:556–564.
A Tailor‐Made Synthetic Polymer for Cell Encapsulation: Design Rationale, Synthesis, Chemical–Physics and Biological Characterizations
Authors: Gerges Irini , Tamplenizza Margherita , Rossi Eleonora , Tocchio Alessandro , Martello Federico , Recordati Camilla , Kumar Deepak , Forsyth Nicholas R. , Liu Yang , Lenardi Cristina
Published: February 2016

This study presents a custom‐made in situ gelling polymeric precursor for cell encapsulation. Composed of poly((2‐hydroxyethyl)methacrylate‐co‐(3‐aminopropyl)methacrylamide) (P(HEMA‐co‐APM) mother backbone and RGD‐mimicking poly(amidoamine) (PAA) moiteis, the comb‐like structured polymeric precursor is tailored to gather the advantages of the two families of synthetic polymers, i.e., the good mechanical integrity of PHEMA‐based polymers and the biocompatibility and biodegradability of PAAs. The role of P(HEMA‐co‐APM) in the regulation of the chemico‐physical properties of P(HEMA‐co‐APM)/PAA hydrogels is thoroughly investigated. On the basis of obtained results, namely the capability of maintaining vital NIH3T3 cell line in vitro for 2 d in a 3D cell culture, the in vivo biocompatibility in murine model for 16 d, and the ability of finely tuning mechanical properties and degradation kinetics, it can be assessed that P(HEMA‐co‐APM)/PAAs offer a cost‐effective valid alternative to the so far studied natural polymer‐based systems for cell encapsulation.

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Polyaniline‐Wrapped ZnO Nanorod Composite Films on Diazonium‐Modified Flexible Plastic Substrates
Authors: Mekki Ahmed , Ait‐Touchente Zouhair , Samanta Soumen , Singh Ajay , Mahmoud Rachid , Chehimi Mohamed M. , Aswal Dinesh K.
Published: February 2016

Vertically aligned core/shell‐like polyaniline‐wrapped ZnO nanorod composite films are prepared on diazonium‐modified biaxially oriented polyethylene terephthalate (BOPET) sheets, in two main steps. (i) The BOPET substrate is modified by grafting of 4‐aminobenzenoic groups from the in situ generated diazonium compound; (ii) ZnO nanorod/polyaniline composite film is grown on the substrates by wet chemical route followed by the preparation of polyaniline (PANI) by in situ chemical oxidative polymerization of aniline on the immobilized ZnO nanorods. Scanning electron microscopy images reveal the vertical growth and homogeneous distribution of the ZnO nanorods and their nanocomposites on the diazonium modified substrates. In contrast, the ZnO and PANI‐coated ZnO nanorods are randomly distributed on pristine BOPET. X‐ray photoelectron spectra permit to characterize the chemical nature of the aryl and the nano­composite adlayers. X‐ray diffraction analysis results indicate that ZnO nanorods retain their wurtzite structure within the nanocomposite coating. Fourier‐transform infrared (FTIR) and Raman indicate the presence of interaction between ZnO nanorods and PANI chains. The ZnO/PANI‐coated diazonium‐modified BOPET sheets exhibit excellent mechanical flexibility with electroconductive characteristics even in the highly bent state. This work highlights the efficiency of the interfacial chemistry of aryl diazonium salts in the preparation of nanocomposite films with outstanding morphology, adhesion, and physical properties even under mechanical stress.

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Synergistic Effect of Functionalized Carbon Nanotubes and Micron‐Sized Rubber Particles on the Mechanical Properties of Epoxy Resin
Authors: Zewde Berhanu , Pitliya Praveen , Karim Alamgir , Raghavan Dharmaraj
Published: February 2016

In this study, the synergistic effect of functionalized carbon nanotubes (fCNT) and micron‐sized rubber particles in improving the thermomechanical properties of epoxy resin is demonstrated. fCNT is mixed with carboxyl‐terminated butadiene acrylonitrile toughened epoxy (CTBNTE) by ultrasonication followed by the addition of curing agent and mixing with planetary shear mixer. A significant improvement is noticed in fracture toughness (≈ 200%) and thermal stability (≈ 12 °C) of fCNT‐filled CTBNTE system but only a marginal improvement in fracture toughness and thermal stability of pristine CNT‐filled CTBNTE relative to epoxy. Dispersion of fCNT is better than pristine CNT in the epoxy matrix. Scanning electron microscope (SEM) images of fractured surface of fCNT‐filled CTBNTE reveal plastic deformation zone, stress whitening, and overall rougher surface compared to pristine CNT‐filled CTBNTE. The findings of our work show promise for use of fCNT in conjunction with a rubber toughener as filler for improving the properties of epoxy resin for advanced structural applications.

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The order of starlikeness of the class of uniformly starlike functions
Authors: Wiśniowska‐Wajnryb Agnieszka
Published: February 2016

We investigate classes of k‐uniformly starlike functions which generalize the class UST introduced by Goodman in 1991. Obtained results enable us to solve the problem of finding the largest such that the class of k‐uniformly starlike functions is contained in the class of starlike functions of order α.
Shear Viscosity of Poly (Acrylamide/Acrylic Acid) Solutions
Authors: Riahinezhad Marzieh , McManus Neil , Penlidis Alexander
Published: February 2016

Acrylamide (AAm)/Acrylic acid (AAc) copolymers are being used in a wide spectrum of applications, from which enhanced oil recovery (EOR) is the target application in this research study. The shear viscosity of the copolymer solution is extremely important in determining the performance properties of AAm/AAc copolymers. A series of copolymers with selected properties were prepared to study the effect of polymer concentration, copolymer composition, and salinity on the shear viscosity of the copolymer solutions. The results revealed the considerable effect of solution concentration and salinity on shear viscosity. Moreover, the behavior of the copolymer composition showed a maximum with respect to shear viscosity.
Conductive Elastomer Composites Based on Inherent and Extrinsic Conductive Polymers
Authors: Rosas‐Aburto Alberto , Roquero‐Tejeda Pedro , Vivaldo‐Lima Eduardo , Pérez‐Salinas Patricia , Phifer Daniel W. , Vázquez R. Javier Revilla
Published: February 2016

Printed Electronics is the designation given to a set of new technological routes for the manufacture of electronic devices which are light, discrete, flexible, and capable of folding. These devices require power sources that share these properties. This paper is focused on how to obtain electrically conductive elastomer composites. These elastomeric composite materials are obtained by mechanical mixing of electronic and ionic conductive polymers with commercial grade styrene‐butadiene rubbers (SBS). The produced materials had good capacitance, thus performing well as rechargeable batteries. These materials were characterized by scanning electron microscopy (SEM) and electrical conductivity measurements to quantify the abundance and distribution of conductive polymers within the rubbery matrix. Our generated experimental results were used to test the predictive power of two mathematical equations based on Hashin–Shtrikman models and composites theory, respectively. Electrical conductivity vs voltage profiles for these conductive elastomer composites were adequately predicted by these models.
Influence of Activation Conditions on the Gas Phase Polymerisation of Propylene
Authors: Cancelas Aarón J. , Monteil Vincent , McKenna Timothy F. L.
Published: February 2016

The impact of injection conditions of a supported Ziegler Natta catalyst on the rate of polymerization of propylene in a gas phase process is investigated. It is observed that the instantaneous rate of propylene polymerization is higher if the catalyst is injected wetted with a hydrocarbon before being charged to the reactor. This is attributed to the effect of the hydrocarbon in decreasing local particle overheating for the critical initial instants of polymerization, due to lower diffusion of the monomer to the active sites and to absorption of the heat of vaporization. An enhancement of the observed initial polymerization rate is also observed with prepolymerization.
Controlled Release of Vitamin B‐12 Using Hydrogels Synthesized by Free Radical and RAFT Copolymerization in scCO2
Authors: Pérez‐Salinas Patricia , Rosas‐Aburto Alberto , Antonio‐Hernández Carlos Hipólito , Jaramillo‐Soto Gabriel , Vivaldo‐Lima Eduardo , Licea‐Claverie Ángel , Castro‐Ceseña Ana Bertha , Vázquez‐Torres Humberto
Published: February 2016

Research in polymer network synthesis is mostly focused on materials with absorbent or controlled‐release properties. They are important in healthcare applications. Free radical copolymerization is the main route to obtain gels, using monomers and crosslinking agents, but the materials produced by this route are highly heterogeneous. These heterogeneities reduce the efficiency of chemical compounds used in controlled‐release applications. Our research is focused on creating new routes of polymer synthesis to reduce these heterogeneities. In this article, we compare gels synthesized by conventional free radical and by reversible addition‐fragmentation chain transfer (RAFT) copolymerization of acrylic monomers in supercritical carbon dioxide. These gels are evaluated for controlled drug delivery applications with vitamin B12. The materials were characterized by scanning electron microscopy (SEM), nitrogen adsorption (BET), differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA). These characterization techniques allowed us to determine the morphology and texture of each hydrogel and to explain how vitamin release performance is affected by these characteristics of the hydrogel.
Multiscale Modeling of Expanding Polyurethane Foams via Computational Fluid Dynamics and Population Balance Equation
Authors: Karimi Mohsen , Droghetti Hermes , Marchisio Daniele L.
Published: February 2016

This study is aimed to formulate a numerical modeling recipe for polyurethane foams. The model is capable of simulating the foam principal characteristics during mold filling. The model is formulated upon coupling of Computational Fluid Dynamics (CFD) and Population Balance Equation (PBE) to predict and simulate the evolution of foam features including apparent density and viscosity, bubble (or cell) size distribution (BSD) during the polymerization, as well as its kinetics. The solution of PBE inside the CFD code is performed with Quadrature Method of Moments (QMOM). The foam, constituted by a liquid polymer and gas bubbles, is simulated as a pseudo‐single‐phase system, while the interface between the foam and the surrounding air is tracked by a Volume‐of‐Fluid (VOF) solver within the open‐source CFD code OpenFOAM. The modeling is applied for a simple foaming experiment and attention is paid to the effect of the rheological model on the predictions.
Fouling in the High Pressure LDPE Process: Experimental and Computational Investigation Approach
Authors: Fries Sebastian , Castañeda‐Zúñiga Diego Mauricio , Duchateau Jan , Neuteboom Peter , Porras Carolina Toloza , Busch Markus
Published: February 2016

A combined experimental and computational approach is presented in order to study reactor fouling in high pressure LDPE tubular reactors. Indications are found that fouling is a process driven by low polymer diffusion speeds and higher friction in the region close to the reactor wall. These findings can explain the formation of polymer rich layers on the reactor wall which are responsible for the reduction of heat transfer and typical tailing observed in molecular weight distributions of LDPE.
Coupled Deterministic and Stochastic Modeling of an Industrial Multi‐Zone LDPE Autoclave Reactor
Authors: Eckes David , Busch Markus
Published: February 2016

Simulation aided product design of LDPE often requires deep understanding of polymer architectures produced in the industrial polymerization. Therefore, a hybrid‐stochastic approach is further developed that allows for the good description of the typical polymeric microstructure produced in a multi‐zone autoclave reactor. The here presented kinetic network goes beyond the basic polymerization scheme and accounts for the propagation of terminal double bonds as well as the mechanical degradation of polymer molecules due to shear stress. By including these reactions a good agreement between experimental and predicted molecular weight distribution is achieved. Furthermore, the comparison of individual contraction factors from experimental data and contraction factors calculated by a 3‐D random walker result in a good agreement.
Production of Polyolefins by Metallocene Catalysts and Their Recycling by Pyrolysis
Authors: Kaminsky Walter
Published: February 2016

Polyolefins are the main industrial used polymers as they are sustainable materials. They show a wide variety of properties, consist of only carbon and hydrogen atoms, can efficiently be produced from easy available monomers and can be recycled. Beside Ziegler‐Natta and Phillips catalysts, metallocenes and other transition metal complexes, activated by methylaluminoxane allow to tailor the structure, the tacticity, and the stereoregularity of polyolefins in a way which has not been reached before. Metallocene catalysts are able to copolymerize ethene or propene with different olefins, cyclic olefins, polar monomers as well as with macromers to form polymer short or long chain branched polymers with new properties. Polyolefin wastes can easily be recycled by extrusion moulding or by pyrolysis to gas and oil. While for extrusion moulding pure polymers have to be used the pyrolysis can take mixed and contaminated polyolefins. In a fluidized bed process, indirectly heated by fire tubes, different products are obtained in dependence of the pyrolysis temperature. By 500°C about 90 % aliphatic waxes are formed, by 700°C mainly olefins and aromatics. By addition of Lewis acids such as titanium or aluminum chlorides to the fluidized bed it is possible to decreasing the pyrolysis temperature by 100 °C.
The free serratus anterior artery perforator flap—A case report and anatomic study
Authors: Park Seong Oh , Chang Hak , Imanishi Nobuaki
Published: February 2016

We report a reconstructive case using a free serratus anterior artery perforator flap and an anatomic study. A 50‐year‐old man with upper esophageal sphincter stricture underwent segmental cervical esophageal resection. The size of the defect was approximately 5.5 cm. We then performed esophageal reconstruction using the free serratus anterior artery perforator flap. Esophagography performed on postoperative day 7 revealed no definite leakage and a viable anastomosis site with wide patency. No complications developed during the long‐term follow‐up period of 3 years. We reviewed the literature and performed an anatomic study using four fresh cadavers. We performed an angiographic study using two specimens and dissection of this perforator using other two specimens. We found that a direct connection existed between the serratus anterior artery and intercostal perforator to the skin in two of eight chests. The connection was located at the 4th intercostal space in the left chest of one cadaver and at the 6th/7th intercostal space in the left chest of the other cadaver. The free serratus anterior artery perforator flap is a new flap that could be considered for use during the elevation of a perforator flap in the lateral chest area, and especially in the area overlying the serratus anterior muscle. © 2016 Wiley Periodicals, Inc. Microsurgery 36:339–344, 2016.
Existence and asymptotic behavior to the incompressible nematic liquid crystal flow in the whole space
Authors: Yang Minghua , Sun Jinyi
Published: February 2016

In this article, first of all, the global existence and asymptotic stability of solutions to the incompressible nematic liquid crystal flow is investigated when initial data are a small perturbation near the constant steady state (0,δ0); here, δ0 is a constant vector with |δ0|=1. Precisely, we show the existence and asymptotic stability with small initial data
for
. The initial data class
of us is not entirely included in the space BMO−1×BMO and contains strongly singular functions and measures. As an application, we obtain a class of asymptotic existence of a basin of attraction for each self‐similar solution with homogeneous initial data. We also study global existence of a large class of decaying solutions and construct an explicit asymptotic formula for ∣x∣→∞, relating the self‐similar profile (U(x),D(x)) to its corresponding initial data (u0,d0). In two dimensions, we obtain higher‐order asymptotics of (u(x),d(x)). Copyright © 2016 John Wiley & Sons, Ltd.
Global stability of a discrete virus dynamics model with Holling type‐II infection function
Authors: Yang Yu , Ma Xinsheng , Li Yahui
Published: February 2016

In this paper, we propose a discrete virus dynamics model with Holling type‐II infection function. By constructing Lyapunov function, we prove that if
, then the infection‐free equilibrium is globally asymptotically stable; whereas if
, then sufficient conditions are established for global stability of the infection equilibrium. Our results generalize some known results studied by other researchers. Copyright © 2015 John Wiley & Sons, Ltd.
Asymptotic expansion for harmonic functions in the half‐space with a pressurized cavity
Authors: Aspri Andrea , Beretta Elena , Mascia Corrado
Published: February 2016

In this paper, we address a simplified version of a problem arising from volcanology. Specifically, as a reduced form of the boundary value problem for the Lamé system, we consider a Neumann problem for harmonic functions in the half‐space with a cavity C. Zero normal derivative is assumed at the boundary of the half‐space; differently, at ∂C, the normal derivative of the function is required to be given by an external datum g, corresponding to a pressure term exerted on the medium at ∂C. Under the assumption that the (pressurized) cavity is small with respect to the distance from the boundary of the half‐space, we establish an asymptotic formula for the solution of the problem. Main ingredients are integral equation formulations of the harmonic solution of the Neumann problem and a spectral analysis of the integral operators involved in the problem. In the special case of a datum g, which describes a constant pressure at ∂C, we recover a simplified representation based on a polarization tensor. Copyright © 2016 John Wiley & Sons, Ltd.
Applications of model theory to the study of ‘soft’ universals in language
Authors: Gilkey Peter , Karousou Alexandra , Ornat Susana López
Published: February 2016

We relate soft universals and efficiency in linguistics to mathematical model theory and recursion. Mathematical models are built from language – complexity theory enters because mathematical model theory is a new higher‐order level part of human cognition within previous linguistic context. Copyright © 2016 John Wiley & Sons, Ltd.
Global behavior of solutions to the fast diffusion equation with boundary flux governed by memory
Authors: Anderson Jeffrey R. , Deng Keng , Wang Qian
Published: February 2016

We study global existence and blow up in finite time for a one‐dimensional fast diffusion equation with memory boundary condition. The problem arises out of a corresponding model formulated from tumor‐induced angiogenesis. We obtain necessary and sufficient conditions for global existence of solutions to the problem. Copyright © 2016 John Wiley & Sons, Ltd.
Existence and nonexistence of positive solutions of a fractional thermostat model with a parameter
Authors: Shen Chunfang , Zhou Hui , Yang Liu
Published: February 2016

In this paper, we investigate positive solutions for boundary value problem of a fractional thermostat model with a parameter. Under different conditions of the function f, existence and nonexistence results for positive solutions are derived in terms of different values of λ. The results are illustrated with an example. Copyright © 2016 John Wiley & Sons, Ltd.
Assessment of vitamin D levels in type 1 and type 2 diabetes patients: Results from metaanalysis
Authors: Shen Liang , Zhuang Qi‐Shuai , Ji Hong‐Fang
Published: February 2016

Scope

Accumulating evidence indicates that vitamin D deficiency is prevalent in patients with type 1 (T1D) and type 2 diabetes (T2D). The present study aims to assess 25‐hydroxyvitamin D [25(OH)D] levels in T1D and T2D patients compared with controls through a metaanalysis.

Methods and results

We searched databases for articles published until January 2015. A total of 12 studies covering 2003 patients and 1882 controls and 11 studies covering 2236 patients and 2438 controls were included to metaanalyze 25(OH)D levels in patients with T1D and T2D, respectively. Pooled data showed that T1D patients had lower levels of 25(OH)D than controls (summary standardized mean difference (SMD) –0.70, 95% confidence interval (CI) –1.02 to –0.37). Further age‐subgroup analysis found that 25(OH)D levels in T1D patients was also significantly lower than controls in subgroup aged ≤ 14 years (summary SMD –1.04, 95% CI –1.55 to –0.53), while the association is not statistically significant in the subgroup aged > 14 years. Similarly, T2D patients had lower 25(OH)D levels compared with controls (summary SMD –0.58, 95%CI –1.16 to –0.00).

Conclusion

Available data indicated that both T1D and T2D patients had lower levels of 25(OH)D than controls overall. The mechanistic underpinnings of this association warrant further elucidation.
Development of a symmetric echo planar imaging framework for clinical translation of rapid dynamic hyperpolarized 13C imaging
Authors: Gordon Jeremy W. , Vigneron Daniel B. , Larson Peder E.Z.
Published: February 2016

Purpose

To develop symmetric echo planar imaging (EPI) and a reference scan framework for hyperpolarized 13C metabolic imaging.

Methods

Symmetric, ramp‐sampled EPI with partial Fourier reconstruction was implemented on a 3T scanner. The framework for acquiring a reference scan on the 1H channel and applied to 13C data was described and validated in both phantoms and in vivo metabolism of [1‐13C]pyruvate.

Results

Ramp‐sampled, symmetric EPI provided a substantial increase in the signal‐to‐noise ratio of the phantom experiments. The reference scan acquired on the 1H channel yielded 13C phantom images that varied in mean signal intensity <2%, compared with 13C images reconstructed with a reference scan directly measured on the 13C channel. The structural similarity index and dynamic time course from in vivo 13C data further support the application of a 1H reference scan to 13C data to mitigate Nyquist ghost artifacts.

Conclusion

Ramp‐sampled, symmetric EPI with spectral‐spatial excitation of a single metabolite provides a fast, robust, and clinically efficacious approach to acquire hyperpolarized 13C dynamic molecular imaging data. The gains of this efficient sampling, combined with partial Fourier methods, enables large matrix sizes required for human studies. Magn Reson Med 77:826–832, 2017. © 2016 International Society for Magnetic Resonance in Medicine