bluuebunny/crossref_metadata_2025 huggingface dataset:
Apheresis in developing countries around the World
Authors: Eichbaum Quentin , Smid W. Martin , Crookes Robert , Naim Norris , Mendrone Alfredo , Marques José Francisco Comenalli , Marques Marisa B.
Published: October 2014

At the combined American Society for Apheresis (ASFA) Annual Meeting/World Apheresis Association (WAA) Congress in San Francisco, California, in April of 2014, the opening session highlighted the status of apheresis outside of the United States. The organizers invited physicians active in apheresis in countries not usually represented at such international gatherings to give them a forum to share their experiences, challenges, and expectations in their respective countries with regard to both donor and therapeutic apheresis. Apheresis technology is expensive as well as technically and medically demanding, and low and median income countries have different experiences to share with the rest of the world. Apheresis procedures also require resources taken for granted in the developed world, such as reliable electrical power, that can be unpredictable in parts of the developing world. On the other hand, it was obvious that there are significant disparities in access to apheresis within the same country (such as in Brazil), as well as between neighboring nations in Africa and South America. A common trend in the presentations from Brazil, Indonesia, Malaysia, Nigeria, and South Africa, was the need for more and better physicians and practitioners' training in the indications of the various apheresis modalities and patient oversight during the procedures. As ASFA and WAA continue to work together, and globalization allows for increased knowledge‐sharing, improved access to apheresis procedures performed by qualified personnel with safety and high‐quality standards will be increasingly available. J. Clin. Apheresis 30:238–246, 2015. © 2014 Wiley Periodicals, Inc.
Performance of different advanced oxidation processes for tertiary wastewater treatment to remove the pesticide acetamiprid
Authors: Carra Irene , Sánchez Pérez José Antonio , Malato Sixto , Autin Olivier , Jefferson Bruce , Jarvis Peter
Published: October 2014

BACKGROUND

This work studied the performance of different advanced oxidation processes (AOPs) as tertiary treatment for removal of the pesticide acetamiprid from water. Specifically, UV, UV/TiO2, UV/H2O2/Fe, and two systems with persulfate (PS), UV/PS and UV/PS/Fe, were evaluated.

RESULTS

The study was carried out in deionised water, synthetic water from a secondary effluent and real effluent from a conventional activated sludge effluent (CAS effluent). In addition, the effect of humic acids, lignin‐derivative and lauryl sulphate was investigated as organic matter that affects AOP efficiency.

CONCLUSIONS

Photo‐Fenton at natural pH proved to be the most efficient process in all matrices. The persulfate systems have also shown that they have great potential for micropollutant removal. It was found that humic acids reduced degradation efficiency for UV/H2O2/Fe and UV/PS/Fe due to competition with radicals. Humic acids had a negative impact on UV photolysis at high concentration due to the absorptivity of UV light. Lignin had a negative effect on AOPs that used iron, forming Fe(II)‐complexes with high absorptivity which act as a light filter. For lauryl sulphate, its chemical structure did not favour the formation of iron complexes at natural pH, resulting in similar degradation rates for UV/H2O2/Fe, UV/H2O2, UV/PS and UV/PS/Fe. © 2014 Society of Chemical Industry
Magnetic nanosized calcium ferrite particles for efficient degradation of crystal violet using a microwave‐induced catalytic method: insight into the degradation pathway
Authors: Shi Wen , Li Qi , An Shuai , Zhang Tingting , Zhang Lei
Published: October 2014

BACKGROUND

Magnetic iron based catalysts with high oxidation performance are generally effective for many catalytic reactions and can be magnetically recovered after application, showing advantages over other metal oxides. In this work, a highly active nanosized CaFe2O4 was prepared by a sol–gel method. Application of the microwave‐induced catalytic degradation (MICD) method to the abatement of crystal violet (CV) using the magnetic catalyst was studied.

RESULTS

More than 90% of CV was degraded within 10 min. The intermediate products were investigated by UV–vis, HPLC and NMR. The results confirmed that CV was completely degraded and converted into harmless products. The reaction kinetics, effect of different ion species (Cl−, SO42−, NO3−, H2PO4− and HPO42−), pH, dye initial concentration, dosage of catalyst, and degradation mechanism were comprehensively studied. It was found that CaFe2O4 presented high activity to produce hydroxyl radicals and holes for degradation of CV under microwave radiation (MW). Surface hydroxyl groups of CaFe2O4 were a critical part in the generation of radicals, and iron on CaFe2O4 surface formed active sites to catalyze CV suggesting that CaFe2O4 plays a significant role in degradation of dyes.

CONCLUSION

This work provides valuable knowledge on the development of CaFe2O4 catalyst for environmental remediation technology. © 2014 Society of Chemical Industry
Synthesis of polyethyleneimine (PEI) and β‐cyclodextrin grafted PEI nanocomposites with magnetic cores for lipase immobilization and esterification
Authors: Khoobi Mehdi , Khalilvand‐Sedagheh Masoud , Ramazani Ali , Asadgol Zahra , Forootanfar Hamid , Faramarzi Mohammad Ali
Published: October 2014

BACKGROUND

Fabrication of nanocomposites with a magnetic core and their applications for enzyme immobilization has been introduced as an intresting trend during recent decades. The present study described the synthesis of polyethyleneimine (PEI) and β‐cyclodextrin grafted PEI nanocomposites with magnetic cores and their applications for lipase immobilization. Fe3O4 magnetic nanoparticles (MNPs) were prepared by co‐precipitation of Fe (III) and Fe (II) ions and then coated with polyethylenimine and/or hydroxyapatite/polyethylenimine, followed by grafting β‐cyclodextrin onto the surface of the prepared nanocomposites. The nanocomposites were then characterized using Fourier transform infrared spectroscopy, X‐ray diffraction, thermogravimetric analysis, vibrating sample magnetometry, and scanning and transmission electron microscopy and consequently applied for the immobilization of lipase.

RESULTS

The results obtained for thermal and pH stability, reusability, and storage stability showed that the MNPs@hydroxyapatite/polyethylenimine/β‐cyclodextrin was the best nanocomposite for lipase immobilization. Application of the immobilized lipase onto the selected nanocomposite for the synthesis of ethyl valerate (green apple flavor) revealed esterification rates of 79% and 62% in n‐hexane and dimethyl sulfoxide, respectively, after 24 h incubation.

CONCLUSION

The results obtained demonstrate good stability, reusability, and potential application of immobilized lipase on magnetic nanocomposite of MNPs@hydroxyapatite/polyethylenimine/β‐cyclodextrin for synthesis of ethyl valerate especially in organic medium. © 2014 Society of Chemical Industry
Targeting Cdk11 in osteosarcoma cells using the CRISPR‐cas9 system
Authors: Feng Yong , Sassi Slim , Shen Jacson K. , Yang Xiaoqian , Gao Yan , Osaka Eiji , Zhang Jianming , Yang Shuhua , Yang Cao , Mankin Henry J. , Hornicek Francis J. , Duan Zhenfeng
Published: October 2014

Osteosarcoma is the most common type primary malignant tumor of bone. Patients with regional osteosarcoma are routinely treated with surgery and chemotherapy. In addition, many patients with metastatic or recurrent osteosarcoma show poor prognosis with current chemotherapy agents. Therefore, it is important to improve the general condition and the overall survival rate of patients with osteosarcoma by identifying novel therapeutic strategies. Recent studies have revealed that CDK11 is essential in osteosarcoma cell growth and survival by inhibiting CDK11 mRNA expression with RNAi. Here, we apply the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)‐Cas9 system, a robust and highly efficient novel genome editing tool, to determine the effect of targeting endogenous CDK11 gene at the DNA level in osteosarcoma cell lines. We show that CDK11 can be efficiently silenced by CRISPR‐Cas9. Inhibition of CDK11 is associated with decreased cell proliferation and viability, and induces cell death in osteosarcoma cell lines KHOS and U‐2OS. Furthermore, the migration and invasion activities are also markedly reduced by CDK11 knockout. These results demonstrate that CRISPR‐Cas9 system is a useful tool for the modification of endogenous CDK11 gene expression, and CRISPR‐Cas9 targeted CDK11 knockout may be a promising therapeutic regimen for the treatment of osteosarcoma. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:199–207, 2015.
Contemporary imaging of soft tissue sarcomas
Authors: Amini Behrang , Jessop Aaron C. , Ganeshan Dhakshina M. , Tseng William W. , Madewell John E.
Published: October 2014

Imaging plays an important role in the diagnosis, biopsy, staging, and follow‐up of patients with soft tissue sarcomas. General principles of imaging diagnosis of soft‐tissue sarcomas using radiography, ultrasound, CT, MRI, and PET/CT will be discussed, with emphasis on the role of location, internal fat and calcification, presence of myxoid stroma, and enhancement characteristics. J. Surg. Oncol. 2015 111:496–503. © 2014 Wiley Periodicals, Inc.
Does cochleostomy location influence electrode trajectory and intracochlear trauma?
Authors: Zhou Ling , Friedmann David R. , Treaba Claudiu , Peng Robert , Roland J. Thomas
Published: October 2014

Objectives/Hypothesis

Trauma to intracochlear structures during cochlear implant insertion is associated with poorer hearing outcomes. One way surgeons can influence insertion trauma is by choosing the surgical approach. We seek to compare cochleostomy (CO), peri–round window (PRW), and round window (RW) approaches using a fresh frozen temporal bone model.

Study Design

Experiments using fresh frozen temporal bones.

Methods

Cochlear implant insertions using the three aforementioned approaches were performed on 15 fresh frozen human temporal bones using a Cochlear 422 electrode. Insertions were evaluated by examining fluoroscopic recordings of histologic sections.

Results

Five cochlear implant insertions were performed using each of the three aforementioned approaches. Fluoroscopic examination revealed that none of the CO or PRW insertions contacted the modiolus during insertion, whereas three of five RW insertions did. RW insertions were less linear during insertion when compared to CO and PRW insertions (P < .05). CO insertions had significantly larger angular depth of insertion (487°) when compared to PRW (413°) and RW (375°) (P < .05). Histologic examination revealed one RW insertion resulted in osseous spiral lamina fracture, whereas the remaining insertions had no evidence of trauma. In the damaged specimen, the inserted electrode was observed to rest in the scala vestibuli, whereas the remaining electrodes rested in the scala tympani.

Conclusions

Due to variability in RW anatomy, a CO or PRW window surgical approach appears to minimize the risk for insertion trauma. However, with favorable anatomy, a Cochlear 422 electrode can be inserted with any of the three approaches.

Level of Evidence

NA Laryngoscope, 125:966–971, 2015
Hierarchical Self‐Assembly of PDMA‐b‐PS Chains into Granular Nanoparticles: Genesis and Fate
Authors: Bianchi Alberto , Mauri Michele , Bonetti Simone , Koynov Kaloian , Kappl Michael , Lieberwirth Ingo , Butt Hans‐Jürgen , Simonutti Roberto
Published: October 2014

The hierarchical self‐assembly of an amphiphilic block copolymer, poly(N,N‐dimethylacrylamide)‐block‐polystyrene with a very short hydrophilic block (PDMA10‐b‐PS62), in large granular nanoparticles is reported. While these nanoparticles are stable in water, their disaggregation can be induced either mechanically (i.e., by applying a force via the tip of the cantilever of an atomic force microscope (AFM)) or by partial hydrolysis of the acrylamide groups. AFM force spectroscopy images show the rupture of the particle as a combination of collapse and flow, while scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images of partly hydrolyzed nanoparticles provide a clear picture of the granular structure.

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Epidermal growth factor‐network signaling mediates luteinizing hormone regulation of BNP and CNP and their receptor NPR2 during porcine oocyte meiotic resumption
Authors: Zhang Wenqiang , Chen Qian , Yang Ye , Liu Wei , Zhang Meijia , Xia Guoliang , Wang Chao
Published: October 2014

The epidermal growth factor (EGF) network, induced by luteinizing hormone (LH), plays an essential role during the regulation of oocyte maturation, cumulus expansion, and ovulation. Binding of brain natriuretic peptide (BNP) and C‐type natriuretic peptide (CNP) to natriuretic receptor 2 (NPR2) generates cyclic guanosine monophosphate (cGMP), a key inhibitor that sustains porcine oocyte meiotic arrest. This correlation suggests that LH interacts with natriuretic‐peptide signaling, possibly via the EGF network, to promote porcine meiotic resumption. In testing this hypothesis, we found that the majority of porcine oocytes remain arrested in the germinal‐vesicle stage after 44 hr of co‐culturing cumulus–oocyte complexes with 107 granulosa cells, which secreted active BNP and CNP; these natriuretic peptides associate with NPR2 on cumulus cells, thereby inhibiting porcine oocyte maturation. This inhibitory effect of BNP and CNP was relieved by EGF‐like growth factors, whose expression naturally increases in granulosa cells 18 hr after human chorionic gonadotropin injection. LH and the EGF‐like peptide amphiregulin (AREG) decreased BNP and CNP production in granulosa cells and down‐regulated NPR2 expression in cumulus cells, which together decreased oocyte cGMP to levels that permit meiotic resumption. The effects of AREG on the gene expression of natriuretic‐peptide signaling components and on oocyte maturation were completely blocked by the EGF receptor kinase inhibitor AG1478; the effect of LH, however, was only partially reversed by AG1478. Based on these results, LH regulates natriuretic‐peptide signaling, although other pathways also cooperate with the EGF network to induce porcine oocyte maturation. Mol. Reprod. Dev. 81: 1030–1041, 2014. © 2014 Wiley Periodicals, Inc.
Thermo‐hydro‐mechanical modeling with Langmuir's adsorption isotherm of the CO2 injection in coal
Authors: Saliya Kanssoune , Grgic Dragan , Giot Richard , Giraud Albert
Published: October 2014

In this paper, we used a theoretical model for the variation of Eulerian porosity, which takes into account the adsorption process known to be the main mechanism of production or sequestration of gas in many reservoir of coal. This process is classically modeled using Langmuir's isotherm. After implementation in Code_Aster, a fully coupled thermo‐hydro‐mechanical analysis code for structures calculations, we used numerical simulations to investigate the influence of coal's hydro‐mechanical properties (Biot's coefficient, bulk modulus), Langmuir's adsorption parameters, and the initial liquid pressure in rock mass during CO2 injection in coal. These simulations showed that the increase in the values of Langmuir's parameters and Biot's coefficient promotes a reduction in porosity because of the adsorption process when the gas pressure increases. Low values of bulk modulus increase the positive effect (i.e., increase) of hydro‐mechanical coupling on the porosity evolution. The presence of high initial liquid pressure in the rock mass prevents the progression of injected gas pressure when CO2 dissolution in water is taken into account. Copyright © 2014 John Wiley & Sons, Ltd.
A survey and performance evaluation of decentralized aggregation schemes for autonomic management
Authors: Makhloufi Rafik , Doyen Guillaume , Bonnet Grégory , Gaïti Dominique
Published: October 2014

Over the last few years, autonomic network and service management has emerged as a serious alternative to traditional management approaches. In these systems, distributed entities, called autonomic managers, perform monitoring and control operations in an autonomous and decentralized way. The monitoring consists of providing indicators on the state of the system. Several monitoring solutions have been proposed to enable autonomic managers to obtain a partial or complete knowledge of an indicator through aggregation processes. Such a profusion of solutions raises important questions regarding the choice of an aggregation scheme in a particular operational context and for a particular management information because each class of solution presents different benefits and weaknesses. That is why, in this paper, we present the result of our study of decentralized aggregation schemes for autonomic network and service monitoring. The contribution is twofold: (i) a survey of decentralized aggregation schemes based on a refined taxonomy; and (ii) the results of an evaluation campaign we performed to compare typical aggregation schemes. These results highlight the context, in terms of the managed network behaviour as well as information dynamics, in which each aggregation scheme outperforms the others, thus helping autonomic management system designers in choosing the best scheme for their management purpose. Copyright © 2014 John Wiley & Sons, Ltd
Stability and accuracy of time‐stepping schemes and dispersion relations for a nonlocal wave equation
Authors: Guan Qingguang , Gunzburger Max
Published: October 2014

A time‐dependent nonlocal wave equation is considered. A feature of the model is that instead of boundary conditions, constraints over regions having finite measures are imposed. The Newmark scheme is considered for discretizing the time derivative and piecewise‐linear finite element methods are used for spatial discretization. For certain ranges of a parameter appearing in the Newmark scheme, unconditional stability is proved; in particular, this result applies to the backward‐Euler‐like and Crank‐Nicolson‐like schemes. For other values of the parameter which includes the forward‐Euler‐like scheme, conditional stability is proved. Dispersion relations for the nonlocal wave equation in one and two dimensions are derived. Comparisons with the analogous results for the classical wave equation are provided as the results of numerical experiments that illustrate the theoretical results. © 2014 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 31: 500–516, 2015
Analysis and numerical solution of stochastic phase‐field models of tumor growth
Authors: Lima Ernesto A. B. F. , Almeida Regina C. , Oden J. Tinsley
Published: October 2014

Carcinogenesis, as every biological process, is not purely deterministic as all systems are subject to random perturbations from the environment. In tumor growth models, the values of the parameters are subjected to many uncertainties that can arise from experimental variations or due to patient‐specific data. The present work is devoted to the development and analysis of numerical methods for the solution of a system of stochastic partial differential equations governing a six‐species tumor growth model. The model system simulates the stochastic behavior of cellular and macrocellular events affecting the evolution of avascular cancerous tissue. It is a continuous phase‐field model that incorporates several key features in tumor dynamics. A sensitivity analysis is performed to identify the more influential parameters. A mixed finite element method and a stochastic collocation scheme are introduced to approximate random‐variables components of the solution. The results of numerous numerical experiments are also presented and discussed. © 2014 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 31: 552–574, 2015
Online stakeholder targeting and the acquisition of social media capital
Authors: Saxton Gregory D. , Guo Chao
Published: October 2014

The diffusion of social media has opened new possibilities for targeted stakeholder communication and, with it, new forms of organizational resources. This article examines the nexus between social media‐based stakeholder communication and the acquisition of social media‐based resources, referred to here as social media capital. After laying out a conceptual mapping of both targeted stakeholder communication and social media capital, the article turns to an inductive analysis of the relationship between the messages 117 US community foundations are sending to their core stakeholders on Twitter and subsequent levels of social media capital. The article thus contributes to the existing literature by elaborating new forms of targeted stakeholder communication, a new type of organizational resource, and the relationship between the two.

Copyright © 2014 John Wiley & Sons, Ltd.
The Necessity of Having a Tetradentate Ligand to Extract Copper(II) Ions from Amyloids
Authors: Nguyen Michel , Rechignat Lionel , Robert Anne , Meunier Bernard
Published: October 2014

The accumulation of redox‐active metal ions, in particular copper, in amyloid plaques is considered to the cause of the intensive oxidation damage to the brain of patients with Alzheimers disease (AD). Drug candidates based on a bis(8‐aminoquinoline) tetradentate ligand are able to efficiently extract Cu2+ from copper‐loaded amyloids (Cu–Aβ). Contrarily, in the presence of a bidentate hydroxyquinoline, such as clioquinol, the copper is not released from Aβ, but remains sequestrated within a Aβ–Cu–clioquinol ternary complex that has been characterized by mass spectrometry. Facile extraction of copper(II) at a low amyloid/ligand ratio is essential for the re‐introduction of copper in regular metal circulation in the brain. As, upon reduction, the Cu+ is easily released from the bis(8‐aminoquinoline) ligand unable to accommodate CuI, it should be taken by proteins with an affinity for copper. So, the tetradentate bis(8‐aminoquinoline) described here might act as a regulator of copper homeostasis.
Cancer‐associated fibroblasts predict poor outcome and promote periostin‐dependent invasion in oesophageal adenocarcinoma
Authors: Underwood Timothy J , Hayden Annette L , Derouet Mathieu , Garcia Edwin , Noble Fergus , White Michael J , Thirdborough Steve , Mead Abbie , Clemons Nicholas , Mellone Massimiliano , Uzoho Chudy , Primrose John N , Blaydes Jeremy P , Thomas Gareth J
Published: October 2014

Interactions between cancer cells and cancer‐associated fibroblasts (CAFs) play an important role in tumour development and progression. In this study we investigated the functional role of CAFs in oesophageal adenocarcinoma (EAC). We used immunochemistry to analyse a cohort of 183 EAC patients for CAF markers related to disease mortality. We characterized CAFs and normal oesophageal fibroblasts (NOFs) using western blotting, immunofluorescence and gel contraction. Transwell assays, 3D organotypic culture and xenograft models were used to examine the effects on EAC cell function and to dissect molecular mechanisms regulating invasion. Most EACs (93%) contained CAFs with a myofibroblastic (α‐SMA‐positive) phenotype, which correlated significantly with poor survival [p = 0.016; HR 7. 1 (1.7–29.4)]. Primary CAFs isolated from EACs have a contractile, myofibroblastic phenotype and promote EAC cell invasion in vitro (Transwell assays, p ≤ 0.05; organotypic culture, p < 0.001) and in vivo (p ≤ 0.05). In vitro, this pro‐invasive effect is modulated through the matricellular protein periostin. Periostin is secreted by CAFs and acts as a ligand for EAC cell integrins αvβ3 and αvβ5, promoting activation of the PI3kinase–Akt pathway. In patient samples, periostin expression at the tumour cell–stromal interface correlates with poor overall and disease‐free survival. Our study highlights the importance of the tumour stroma in EAC progression. Paracrine interaction between CAF‐secreted periostin and EAC‐expressed integrins results in PI3 kinase–Akt activation and increased tumour cell invasion. Most EACs contain a myofibroblastic CAF‐rich stroma; this may explain the aggressive, highly infiltrative nature of the disease, and suggests that stromal targeting may produce therapeutic benefit in EAC patients. © 2014 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
Polyvinyl alcohol‐modified Pithecellobium Clypearia Benth herbal residue fiber/polypropylene composites
Authors: Feng Yanhong , Chen Hong , Dong Xiaolong , Qu Jinping , He Hezhi , Xu Baiping , Zhang Yeqing
Published: October 2014

Pithecellobium Clypearia Benth herbal residues (PHRs) were pretreated by steam explosion to produce PHR fibers (PHRFs) that were subsequently co‐steam explosion modified with various molecular weight of polyvinyl alcohol (PVA). High value use of PHRs was realized when the unmodified PHRFs and modified PHRFs were used to reinforce polypropylene (PP). The component and structural changes of PHRFs, as well as the mechanism of PVA action during co‐steam explosion, were analyzed. The effect of the PVA co‐steam explosion on the mechanical properties, water absorption and interfacial properties of PHRF/PP composites were also studied as a function of PVA molecular weight. Relative to unmodified‐PHRF/PP composites, the mechanical and interfacial properties were improved, while water absorption was almost unchanged, for composites containing PHRFs modified by PVA co‐steam explosion. This was because PVA had been grafted on to the PHRFs during the co‐steam explosion. POLYM. COMPOS., 37:915–924, 2016. © 2014 Society of Plastics Engineers
Polyaniline/silver nanocomposites synthesized via UV–Vis‐assisted aniline polymerization with a reversed micellar microemulsion system
Authors: Li Zhihua , Li Yanbo , Lin Wei , Zheng Feng , Laven Jozua
Published: October 2014

Polyaniline (PANI)/silver (Ag) nanocomposites were successfully synthesized within a sodium dodecyl sulfate reverse micro‐emulsion system and characterized by Fourier transform infrared spectroscopy, X‐ray diffraction, ultraviolet spectrometry, thermogravimetric analysis, scanning electron microscopy, transmission electron microscopy, and electrochemical methods. The results show that the core‐shell nanoparticles of less than 100 nm may be synthesized with PANI as shell formed around a core of nanoparticle. PANI/Ag nanocomposite prepared by this method has better thermal stability, higher conductivity, and electrochemical performance. The maximum conductivity (95.5 S/cm) was obtained when W0 (water‐oil ratio) is 22. Cyclic voltammograms results show that PANI/Ag prepared by this method has a high response current and large capacitance. Polarization results show that Ecorr (174.1 mV) and Icorr (50.6 μA/cm2) are better than the results for PANI and for PANI/Ag prepared by micro‐emulsion method. PANI/Ag nanocomposites prepared by the current method have potential applications in electrode materials, capacitors, conductive adhesives, and anticorrosion materials. POLYM. COMPOS. 37:1064–1071, 2016. © 2014 Society of Plastics Engineers
The Effect of CNT‐modified matrix of cyanate ester CFRPs on the hydrothermal behavior of the material. Evaluation of the water uptake using electrical resistance measurements
Authors: Kotrotsos A. , Vavouliotis A. , Loutas T. , Kostopoulos V.
Published: October 2014

In this work, reference and nanomodified unidirectional cyanate matrix, carbon fiber‐reinforced polymers (CFRPs), were exposed to distilled water at 80°C. Water uptake was investigated as a function of the carbon nanotube CNT wt% content up to saturation level. In parallel the variation of glass transition temperature (Tg) was also monitored using dynamic mechanical analysis tests. The distilled water absorption process was modeled following the Fick's law, and the experimental results were found to be in very good agreement with the theoretical predictions up to saturation. Finally, during the tests and, at defined time intervals the variation of the electrical conductivity of the materials under investigation was studied and a correlation between the water absorption and the variation of the electrical conductivity was established. It was shown that the presence of CNTs into the cyanate matrix affects the water absorption mechanism, since an important amount of additional interfaces has been introduced. POLYM. COMPOS. 37:1072–1077, 2016. © 2014 Society of Plastics Engineers
Preparation and properties of peroxide dynamically vulcanized poly(vinylidene fluoride)/silicone rubber/zinc dimethacrylate composites
Authors: Wang Yanpeng , Chen Zhonghua , Ding Jianping , Chen Yukun
Published: October 2014

Composites of poly(vinylidene fluoride) (PVDF), silicone rubber (SR), and zinc dimethacrylate (ZDMA) were prepared via peroxide dynamic vulcanization. The effect of ZDMA loading on the morphology, mechanical properties, and rheology of the PVDF/SR/ZDMA composite was investigated. It was found that, some rubber particles with different diameters were aggregated and distributed in the PVDF matrix. The average diameters of rubber particles increased when ZDMA was incorporated into the PVDF/SR blend. A higher content of ZDMA seemed to show a favorable effect on the mechanical properties of PVDF/SR/ZDMA composites. The tensile strength, flexural strength, and flexural modulus of PVDF/SR/ZDMA composites decreased with increasing the ZDMA loading, which was due to the decreased tensile strength and total crosslink density of SR/ZDMA composite and the increased diameter of rubber particles, but the compatibility and interfacial interaction between PVDF phase and SR phase were obviously improved, which contributed to improved the Izod impact strength. In addition, the rheology analysis also suggested that interfacial adhesion between PVDF phase and SR phase was improved due to the incorporation of ZDMA. POLYM. COMPOS. 37:1093–1100, 2016. © 2014 Society of Plastics Engineers
Maleated high oleic sunflower oil‐treated cellulose fiber‐based styrene butadiene rubber composites
Authors: Raza Mohsin A. , Ashraf Muhammad A. , Westwood Aidan V.K. , Jamil Tahir , Ahmad Rafiq , Inam Aqil , Deen Kashif M.
Published: October 2014

Surface treatment of cellulose fibers was performed with maleated high oleic sunflower oil (MSOHO). The MSOHO‐treated cellulose fibers and unmodified cellulose fibers were dispersed in styrene butadiene rubber (SBR) using a two roll mill. Vapor grown carbon nanofibers (VGCNF) were also incorporated at only one parts per hundred rubber (phr) in unmodified cellulose fibers/SBR composites. The curing characteristics, mechanical properties, and water absorption of the resulting composites were determined. MSOHO‐treated fibers completed curing at much slower rate and also decreased the cure density of composites, compared to unmodified fibers. In contrast, the combination of VGCNF and unmodified cellulose fibers accelerated the SBR curing process, but reduced the cure density. MSOHO treatment improved the dispersion of the fibers in the SBR, which resulted in improved mechanical properties of composites. The composite incorporating 1 phr VGCNF and 15 phr unmodified cellulose fibers showed the greatest increase in tensile strength as compared with neat SBR. POLYM. COMPOS. 37:1113–1121, 2016. © 2014 Society of Plastics Engineers
Accuracy of prenatal diagnosis of isolated aqueductal stenosis
Authors: Emery Stephen P. , Hogge W. Allen , Hill Lyndon M.
Published: October 2014

Objective

The objective of this article is to determine the success rate of prenatally diagnosed isolated aqueductal stenosis (AS) as a first step in an evidence‐based reassessment of ventriculoamniotic shunting for isolated AS.

Methods

Cases of ventriculomegaly at Magee‐Womens Hospital between 2006 and 2013 were ascertained. AS was suspected when prenatal ultrasound and magnetic resonance imaging (MRI) demonstrated signs of pressure hydrocephalus. The prenatal diagnosis generated by ultrasound and MRI was compared with the postnatal diagnosis based upon neonatal neuroimaging.

Results

The initial query of the Magee‐Womens Hospital database resulted in 370 cases of ventriculomegaly. After exclusion for associated central nervous system malformations, 110 cases of severe ventriculomegaly remained. The imaging studies on each fetus were reviewed, and cases of prenatally diagnosed AS were identified. The median gestational age of the ultrasound diagnosis and prenatal MRI was 23 weeks 3 days and 33 weeks 3 days, respectively. All cases of prenatally suspected isolated AS (six of six) and cases of AS with other associated central nervous system anomalies (six of six) were correctly identified.

Conclusion

An accurate prenatal diagnosis of isolated fetal AS is possible. This is an important first step in an evidence‐based reassessment of ventriculoamniotic shunting for isolated AS. © 2014 John Wiley & Sons, Ltd.
NEUROPSYCHOLOGY OF CHILD MALTREATMENT AND IMPLICATIONS FOR SCHOOL PSYCHOLOGISTS
Authors: Davis Andrew S. , Moss Lauren E. , Nogin Margarita M. , Webb Nadia Elizabeth
Published: October 2014

Child maltreatment has the potential to alter a child's neurodevelopmental trajectory and substantially increase the risk of later psychiatric disorders, as well as to deleteriously impact neurocognitive functioning throughout the lifespan. Child maltreatment has been linked to multiple domains of neurocognitive impairment, including language, visual–spatial functioning, intelligence, executive functioning, and motor skills. Research is increasingly indicating that alterations in neurobiological functioning occur as a result of childhood maltreatment, which in turn may produce an epigenetic and transgenerational effect. School psychologists should be aware of these factors when working with maltreated children to better understand their current functioning and assessment results, and to educate family members, school personnel, and the community about the adverse effects of childhood maltreatment, as well as to work toward prevention.
Expression of soluble triggering receptor expressed on myeloid cells‐1 in childhood CF and non‐CF bronchiectasis
Authors: Masekela R. , Anderson R. , de Boeck K. , Vreys M. , Steel H.C. , Olurunju S. , Green R.J.
Published: October 2014

Background

Soluble triggering receptor expressed on myeloid cells‐1 (sTREM‐1) is demonstrating promise as an inflammatory biomarker of acute infection in various pulmonary conditions; including community acquired pneumonia, ventilator associated pneumonia and non‐tuberculous mycobacterial infection.

Introduction

The expression of sTREM‐1 has been poorly studied in all forms of bronchiectasis, both in the context of cystic fibrosis (CF) and non‐cystic fibrosis bronchiectasis.

Method

: Induced sputum samples were collected for sTREM‐1 determination in children with HIV‐associated bronchiectasis and CF‐bronchiectasis. The presence or absence of an exacerbation was noted at study entry. Lung function parameters (FEV1, FVC, FEV1/FVC, FEF25–75) were measured using the Viasys SpiroPro Jaeger Spirometer (Hoechberg, Germany).

Result

: A total of twenty‐six children with HIV‐associated bronchiectasis and seventeen with CF were included. With respect to sTREM‐1, the levels were readily detected in both groups, but were significantly higher in children with HIV‐associated bronchiectasis (1244.0 pg/ml (iqr 194.5; 3755.3 pg/ml) and 204.9  pg/ml (iqr 66.9; 653.6 pg/ml) P = 0.003. There was a positive correlation between sTREM‐1 and IL‐8 as well as sputum neutrophil elastase in the HIV‐bronchiectasis group (r = 0.715 and r = 0.630), respectively both P < 0.005. sTREM‐1 was not further increased in subjects presenting with an acute pulmonary exacerbation in the HIV‐associated bronchiectasis and in CF participants (P = 0.971 and P = 0.481), respectively. In the CF group sTREM‐1 strongly correlated with FVC% predicted and FEV1% predicted (r = 0.950 and r = 0.954), both P < 0.005.

Conclusion

The pulmonary innate immune functions are over‐active in HIV‐associated bronchiectasis, with readily detected sTREM‐1 values, which were higher than those in CF. sTREM‐1 does not correlate with markers of HIV‐disease activity but does correlate with markers of neutrophilic inflammation. In CF sTREM‐1 has a negative correlation with pulmonary function parameters. Pediatr Pulmonol. 2015; 50:333–339. © 2014 Wiley Periodicals, Inc.
Slow‐release formulations of the herbicide MCPA by using clay–protein composites
Authors: Alromeed Alaa Aldin , Scrano Laura , A. Bufo Sabino , Undabeytia Tomás
Published: October 2014

BACKGROUND

MCPA [(4‐chloro‐2‐methylphenoxy) acetic acid] is a widely used herbicide showing high leaching in the soil. In this study, clay–protein‐based formulations of this herbicide were designed to reduce the risk of water pollution resulting from conventional formulations.

RESULTS

Clay–gelatin formulations of MCPA were prepared, and the influence of synthesis parameters such as pH and the presence of a plasticiser (glycerol) on the active substance content and performance of the new formulations was examined. Differential scanning calorimetry measurements provided information on the stability of the gelatin matrix in the gelatin–clay complex. Fourier transform infrared spectroscopy showed that the herbicide was retained by the formation of hydrogen bonds with side amino groups of the protein backbone and polyion complexation. Clay–protein‐based formulations prepared at a pH below the isoelectric point value of the protein and in the absence of glycerol provided the slowest release of MCPA in water. Soil column experiments showed a fourfold reduction in leaching and improved bioactivity in the upper soil layer for the new formulation compared with a commercial product used as a control.

CONCLUSIONS

A reduction in the recommended dose of MCPA can be achieved by employing clay–gelatin, which reduces the environmental risk associated with herbicide applications. © 2014 Society of Chemical Industry
Electron spin lifetime in chemically synthesized graphene sheets
Authors: Náfrádi Bálint , Forró László , Choucair Mohammad
Published: October 2014

Graphene is theoretically expected to be a highly suitable material for spintronic and quantum computation applications. Current experimental reports assign surprisingly low spin lifetimes to graphene and related carbon structures. Recently, we showed a solvothermal synthesis method that can be employed to produce a high‐purity sample, which approximates very well the assembly of graphene sheets. Using the contactless spectroscopic technique of electron spin resonance (ESR), we were able to identify in this graphene material the ESR of both conduction electrons and localized spins [Náfrádi et al., Carbon 74, 346–351 (2014)]. Here, we show the temperature dependent evolution of the ESR of these two spin species.
Similarity theory based on the Dougherty–Ozmidov length scale
Authors: Grachev Andrey A. , Andreas Edgar L , Fairall Christopher W. , Guest Peter S. , Persson P. Ola G.
Published: October 2014

This article describes a local similarity theory for developed turbulence in the stably stratified boundary layer that is based on the Brunt–Väisälä frequency and the dissipation rate of turbulent kinetic energy instead of the turbulent fluxes used in the traditional Monin–Obukhov similarity theory. Based on dimensional analysis (Pi theorem), it is shown that any properly scaled statistics of the small‐scale turbulence are universal functions of a stability parameter defined as the ratio of a reference height z and the Dougherty–Ozmidov length scale, which in the limit of z‐less stratification is linearly proportional to the Obukhov length scale. Measurements of atmospheric turbulence made at five levels on a 20 m tower over the Arctic pack ice during the Surface Heat Budget of the Arctic Ocean experiment (SHEBA) are used to examine the behaviour of different similarity functions in the stable boundary layer. In the framework of this approach the non‐dimensional turbulent viscosity is equal to the gradient Richardson number, whereas the non‐dimensional turbulent thermal diffusivity is equal to the flux Richardson number. These results are a consequence of the approximate local balance between production of turbulence by shear in the mean flow and viscous dissipation. The turbulence framework based on the Brunt–Väisälä frequency and the dissipation rate of turbulent kinetic energy may have practical advantages for estimating turbulence when the fluxes are not directly available.
A novel high‐temperature combustion based system for stable isotope analysis of dissolved organic carbon in aqueous samples. I: development and validation
Authors: Federherr E. , Cerli C. , Kirkels F. M. S. A. , Kalbitz K. , Kupka H. J. , Dunsbach R. , Lange L. , Schmidt T. C.
Published: October 2014

RATIONALE

Traditionally, dissolved organic carbon (DOC) stable isotope analysis (SIA) is performed using either offline sample preparation followed by elemental analyzer/isotope ratio mass spectrometry (EA/IRMS) or a wet chemical oxidation (WCO)‐based device coupled to an isotope ratio mass spectrometer. The first method is time‐consuming and laborious. The second involves the risks of underestimation of DOC concentration and isotopic fractionation due to incomplete oxidation. The development of an analytical method for accurate and sensitive DOC SIA is described in this study.

METHODS

A high‐temperature combustion (HTC) system improves upon traditional methods. A novel total organic carbon (TOC) system, specially designed for SIA, was coupled to an isotope ratio mass spectrometer. An integrated purge and trap technique (peak focusing), flexible injection volume (0.05–3 mL), favorable carrier gas flow, modified ash crucible, new design of combustion tube and optimized drying system were used to achieve the necessary performance.

RESULTS

The system can reliably measure concentrations up to 1000 mgC/L. Compounds resistant to oxidation, such as barbituric acid, melamine and humic acid, were analyzed with recovery rates of 100 ± 1% proving complete oxidation. In this initial testing, the δ13C values of these compounds were determined with precision and trueness of ≤0.2‰ even with 3.5% salinity. Further tests with samples with low DOC concentrations resulted in LOQSIA method values of 0.5 mgC/L and 0.2 mgC/L for LOQSIA instr, considering an accuracy of ±0.5‰ as acceptable.

CONCLUSIONS

The novel HTC system coupled to an isotope ratio mass spectrometer resulted in significantly improved sensitivity. The system is suitable for salt‐containing liquids and compounds that are resistant to oxidation, and it offers a large concentration range. A second paper (which follows this one in this issue) will present a more comprehensive assessment of the analytical performance with a broad set of solutions and real samples. This highly efficient TOC stable isotopic analyzer will probably open up new possibilities in biogeochemical carbon cycle research. Copyright © 2014 John Wiley & Sons, Ltd.
Assessment of acylation routes and structural characterisation by liquid chromatography/tandem mass spectrometry of semi‐synthetic acyl ester analogues of lipophilic marine toxins
Authors: de la Iglesia Pablo , Fonollosa Elena , Diogène Jorge
Published: October 2014

RATIONALE

Esterification is one of the most important metabolic routes of lipophilic marine toxins in shellfish. In this work we assessed several chemical acylation reactions aimed at obtaining acyl ester analogues via partial synthesis from the free toxins. The procedures developed including sensitive and selective methods based on liquid chromatography/tandem mass spectrometry (LC/MS/MS) can be applied to obtain reference materials that may be used as analytical standards (internal/external) for method development and calibration, as well as to perform toxicological in vitro and in vivo studies.

METHODS

Acylation systems involved both anhydrous and non‐anhydrous fatty acid or acid halides as a source of the acyl radical, and several catalysers of the reaction. A series of mass spectrometric experiments involving product ion scans and multiple reaction monitoring (MRM) were used to confirm the identity and to elucidate the fragmentation pathways of the synthesised products.

RESULTS

Reaction yields regarding reaction time and temperature were examined at sub‐nmol scale for the acylation system consisting of palmitic anhydride and 4‐(dimethylamino)pyridine (DMAP) in anhydrous pyridine, showing the best conditions at 75 °C for 60 min, 75 °C for 120 min and 100 °C for 270 min for cyclic imines, azaspiracid‐1 and pectenotoxin‐2, respectively. The esterification approach was verified at a larger scale for the esterification of gymnodimine‐A (GYM‐A), which kept a good yield >90% for the synthesis of 10‐O‐palmitoyl‐GYM‐A.

CONCLUSIONS

Acyl ester analogues of lipophilic marine toxins have been synthesised and their structure elucidated by LC/MS/MS. For acyl ester analogues identical to natural metabolites, the procedures developed have potential to be applied for the semi‐synthesis of metabolites in a sustainable, scalable and controlled way, avoiding extensive and tedious isolation and purification procedures from naturally contaminated shellfish. For the semi‐synthetic esters structurally different than those found in shellfish, they may have applicability as internal standards for accurate quantifications of natural metabolites present in complex matrices. Copyright © 2014 John Wiley & Sons, Ltd.
Innovation means open minds and open doors
Authors: Bowman Jo
Published: October 2014

Big businesses need to think like start‐ups—and sometimes invite them on board, says Telefónica strategic development executive Richard Blades.
When mobile qualitative works best
Authors: August Steve
Published: October 2014

Mobile is the answer … now, what's the question?
Wanted: Mobile Audiences
Authors: Mareck Manfred
Published: October 2014

Does growing mobile‐device usage impact media consumption?
Coupled variable selection for regression modeling of complex treatment patterns in a clinical cancer registry
Authors: Schmidtmann I. , Elsäßer A. , Weinmann A. , Binder H.
Published: October 2014

For determining a manageable set of covariates potentially influential with respect to a time‐to‐event endpoint, Cox proportional hazards models can be combined with variable selection techniques, such as stepwise forward selection or backward elimination based onp‐values, or regularized regression techniques such as component‐wise boosting. Cox regression models have also been adapted for dealing with more complex event patterns, for example, for competing risks settings with separate, cause‐specific hazard models for each event type, or for determining the prognostic effect pattern of a variable over different landmark times, with one conditional survival model for each landmark. Motivated by a clinical cancer registry application, where complex event patterns have to be dealt with and variable selection is needed at the same time, we propose a general approach for linking variable selection between several Cox models. Specifically, we combine score statistics for each covariate across models by Fisher's method as a basis for variable selection. This principle is implemented for a stepwise forward selection approach as well as for a regularized regression technique. In an application to data from hepatocellular carcinoma patients, the coupled stepwise approach is seen to facilitate joint interpretation of the different cause‐specific Cox models. In conditional survival models at landmark times, which address updates of prediction as time progresses and both treatment and other potential explanatory variables may change, the coupled regularized regression approach identifies potentially important, stably selected covariates together with their effect time pattern, despite having only a small number of events. These results highlight the promise of the proposed approach for coupling variable selection between Cox models, which is particularly relevant for modeling for clinical cancer registries with their complex event patterns. Copyright © 2014 John Wiley & Sons, Ltd.