bluuebunny/crossref_metadata_2025 huggingface dataset:
Ilex paraguariensis crude extract acts on protection and reversion from damage induced by t‐butyl hydroperoxide in human erythrocytes: a comparative study with isolated caffeic and/or chlorogenic acids
Authors: Portela José Luiz , Soares Deividi , Rosa Hemerson , Roos Daniel Henrique , Pinton Simone , Ávila Daiana Silva , Puntel Robson L
Published: August 2016

BACKGROUND

Studies comparing the effects of phytochemicals under different regimens of exposure are necessary to give a better indication about their mechanism(s) of protection. Hence, in the present study, we investigated the preventive (pre‐incubation), protective (co‐incubation) and/or remediative (post‐incubation) activity of chlorogenic acid and caffeic acids, in comparison with Ilex paraguariensis crude extract, against t‐butyl hydroperoxide (t‐BHP)‐induced damage to human erythrocytes.

RESULTS

We found that both caffeic and chlorogenic acids were able to prevent and revert the hemolysis associated with t‐BHP exposure. By contrast, isolated compounds (alone or in combination) presented no effect on basal and/or t‐BHP‐induced non‐protein thiol (NPSH) oxidation or production of thiobarbituric acid reactive substances (TBBARS). In turn, I. paraguariensis extract was effective to prevent, protect and revert the hemolysis associated with t‐BHP exposure. Moreover, I. paraguariensis significantly protects and reverts t‐BHP‐induced NPSH oxidation and TBARS production.

CONCLUSIONS

We have found that I. paraguariensis extract acts better with respect to the protection and reversion of t‐BHP‐associated changes, whereas isolated compounds are more active in preventing and reverting t‐BHP pro‐hemolytic action. Moreover, our data suggest that the pro‐hemolytic activity of t‐BHP may occur via mechanism(s) other(s) than lipid peroxidation and/or NPSH oxidation. © 2016 Society of Chemical Industry
Imidazolium‐embedded iodoacetamide‐functionalized silica‐based stationary phase for hydrophilic interaction/reversed‐phase mixed‐mode chromatography
Authors: Wang Huizhen , Zhang Lu , Ma Teng , Zhang Liyuan , Qiao Xiaoqiang
Published: August 2016

A novel imidazolium‐embedded iodoacetamide‐functionalized silica‐based stationary phase has been prepared by surface radical chain‐transfer polymerization. The stationary phase was characterized by Fourier transform infrared spectrometry, thermogravimetric analysis, and element analysis. Fast and efficient separations of polar analytes, such as nucleosides and nucleic acid bases, water‐soluble vitamins and saponins, were well achieved in hydrophilic interaction chromatography mode. Additionally, a mixed mode of hydrophilic interaction and reversed‐phase could be also obtained in the analysis of polar and nonpolar compounds, including weak acidic phenols, basic anilines and positional isomers, with high resolution and molecular‐planarity selectivity, outperforming the commercially available amino column. Moreover, simultaneous separation of polar and nonpolar compounds was also achieved. In conclusion, the multimodal retention capabilities of the imidazolium‐embedded iodoacetamide‐functionalized silica‐based column could offer a wide range of retention behavior and flexible selectivity toward hydrophilic and hydrophobic compounds.
Rapid magnetic solid‐phase extraction of Congo Red and Basic Red 2 from aqueous solution by ZIF‐8@CoFe2O4 hybrid composites
Authors: Xu Yan , Jin Jingjie , Li Xianliang , Han Yide , Meng Hao , Wu Junbiao , Zhang Xia
Published: August 2016

Core–shell metal–organic framework materials have attracted considerable attention mainly due to their enhanced or new physicochemical properties compared with their single‐component counterparts. In this work, a core–shell heterostructure of CoFe2O4‐Zeolitic Imidazolate Framework‐8 (ZIF‐8@CoFe2O4) is successfully fabricated and used as an solid‐phase extraction adsorbent to efficiently extract Congo Red and Basic Red 2 dyes from contaminated aqueous solution. Vibrating sample magnetometry indicates that the saturated magnetization of ZIF‐8@CoFe2O4 is 3.3 emu/g, which is large enough for magnetic separation. The obtained hybrid magnetic metal‐organic framework based material ZIF‐8@CoFe2O4 can remove the investigated dyes very fast within 1 min of the contact time. The adsorbent ZIF‐8@CoFe2O4 also shows a good reusability. After regeneration, the adsorbent can still exhibit high removal efficiency (∼97%) toward Congo Red for five cycles of desorption–adsorption. This work reveals the great potential of core–shell ZIF‐8@CoFe2O4 sorbents for the fast separation and preconcentration of organic pollutants in aqueous solution before high‐performance liquid chromatography analysis.
Einflußeiner Verzinkung auf die Korrosion von mit Zementmörtel beschichtetem Stahl in NaCl‐Lösung
Authors: Hildebrand Heinrich , Schwenk W.
Published: August 2016

Verzinkte oder gebeizte Blechproben wurden mit Portlandzement‐Mörtel unterschiedlicher Erhärtung und Wasserzementwerte beschichtet und 1 bis 5 Jahre in 0,5 M NaCl vollständig oder zur Hälfte eingetaucht. In Abhängigkeit von der Versuchsdauer wurden die Freien Korrosionspotentiale und elektrische Widerstände gemessen.

Den größten Einfluß auf die Korrosionsbeständigkeit der Bleche haben die Verzinkung und die Tauchart.

Vollständig eingetauchte Proben zeigen sehr negative Potentiale. Sie können deshalb als Kathoden in Korrosionselementen nicht wirksam werden. Die Bleche korrodieren im Mörtel nahezu nicht. Zur Hälfte eingetauchte Proben zeigen verhältnismäßig positive Potentiale. Auch bei verzinkten Proben wird das Potential im Laufe der Zeit zu gleich positiven Potentialen verschoben. Solche Proben kommen somit als Kathoden für Korrosionselemente infrage. An der Wasser/Luft‐Grenze entsteht örtliche Korrosion. Bei unverzinkten Proben kann die Mörtelschicht durch Korrosionsprodukte aufbrechen. Bei verzinkten Proben kann die örtliche Korrosion wesentlich verzögert werden.

Im Detail werden die Ergebnisse zur Klärung praktischer Probleme der Elementbildung, des inneren und äußeren Rohrschutzes und des Bewertungsstahls bei Stahl‐Wasser‐Bauten erörtert.
Untersuchungen zur Werkstoffschädigung im Hochtemperatur‐LCF‐Bereich
Authors: Lachmann E.
Published: August 2016

Das Werkstoffverhalten unter Hochtemperatur‐LCF‐Beanspruchung wird überwiegend von den zeitabhängigen Schädigungsprozessen Kriechen und Oxidation (Umgebungseinfluß) bestimmt. Zur Untersuchung der Einflußgrößen Dehngeschwindigkeit, Zyklusform und Umgebung auf die Werkstoffschädigung wurden dehnungsgesteuerte Zug‐Druck‐Wechselversuche an Proben aus 13 CrMo 44 und X 10 CrNiTi 18 9 bei 560°C bzw. 530°C durchgeführt.

Anhand umfangreicher metallographischer und mikrofraktographischer Untersuchungen wird die Wechselwirkung von zyklischer Wechselverformung (Ermüdung), Umgebung (Oxidation) und Kriechen (Relaxation) auf die Werkstoffschädigung dargestellt. Es wird weiterhin gezeigt, daß die für das Ermüdungsverhalten hauptsächlich verantwortliche Einflußgröße von den Parametern Werkstoff, Beanspruchungshöhe, Dehngeschwindigkeit und Zyklusform abhängt.
On the atmospheric corrosion of thin copper films
Authors: v. d. Leest R. E.
Published: August 2016

Sputtered and electrodeposited copper specimens were exposed to the laboratory atmosphere for 18 months, after which the corrosion products were analysed by electrochemical methods and reflectance spectra. The formation of corrosion products takes place in three stages: initially cuprous oxide is formed, followed by the growth of cuprous sulphide, and finally cuprous oxide is converted to cuprous sulphide. The presence of water is essential for these corrosion reactions to occur.
Korrosionselektrochemisches Verhalten von Eisen‐Nickel‐Legierungen in sauren Sulfidlösungen
Authors: Raicheff R. , Aroyo M. , Arpadjan S.
Published: August 2016

Mit Hilfe der Methode des Polarisationswiderstandes und der potentiodynamischen Polarisationsmessungen wurde der Einfluß des Schwefelwasserstoffs auf das korrosionselektrochemische Verhalten der Eisen‐Nickel‐Legierungen in schwefelsauren Medien untersucht. Es wurde festgestellt, daß das H2S stimulierend auf die Korrosionsgeschwindigkeit wirkt. Diese Wirkung hängt vom pH‐Wert der Lösung, von der Zusammensetzung und der Struktur der Legierungen ab und ist für Legierungen mit erhöhtem Nickelgehalt stärker ausgeprägt. Es wurde gezeigt, daß die Anwesenheit des H2S in der Lösung sowohl auf die anodische Reaktion der Metallauflösung, als auch auf die kathodische Reaktion der Wasserstoffabspaltung wirkt. Die Unterschiede im elektrochemischen Verhalten der beiden Fe‐Ni‐Legierungen (mit einer Struktur der α‐ und γ‐Phase) zeigen sich in Gegenwart von H2S nur bei der kathodischen Reaktion. Mittels Atomabsorptionsanalyse wurde festgestellt, daß die Anwesenheit des H2S in schwefelsauren Medien keine selektive Auflösung der Komponenten der Fe‐Ni‐Legierungen verursacht.
Reaktionen zwischen Natriumpolysulfid und Stromabnehmermaterialien für Natrium/Schwefel‐Batterien
Authors: Heusler K. E. , Grzegorzewski A.
Published: August 2016

Zur Messung der Korrosionsgeschwindigkeit von Materialien, die als Stromabnehmer in der Natriumpolysulfidschmelze von Natrium/Schwefel‐Batterien interessant sind, wurden die zeitlichen Veränderungen der Dicke dünner Schichten in situ mit einer 4‐Punkt‐Widerstandsmethode verfolgt. Die stationäre Korrosionsgeschwindigkeit des Aluminiums am Ruhepotential war in Na2S4 bei 350°C ⩽ 150 μm/a, die Aktivierungsenthalpie 300 kJ/mol. Die Korrosionsgeschwindigkeit wuchs mit dem Quadrat des kathodischen Gesamtstroms an. Anodische Polarisation erhöhte die Dicke der passivierenden Deckschicht, kaum die mittlere Korrosionsgeschwindigkeit, und führte zu lokal unterschiedlichen Geschwindigkeiten.

Auf dem Stahl X10CrA124 (W.Nr. 1.4762) wuchs eine Deckschicht nach dem parabolischen Zeitgesetz, bis eine stationäre Korrosionsgeschwindigkeit, bei 350°C etwa 90 μm/a, erreicht war. Der aluminiumfreie Stahl X10CrNiMoTi 18 10 (W.Nr. 1.4571) korrodierte mit der Geschwindigkeit von 1,5 mm/a. Die Korrosionsgeschwindigkeit, bei 350°C etwa 90 μm/a, ereicht war. Der aluminiumfreie Stahl X10CrNiMoTi 18 10 (W.Nr. 1.4571) korrodierte mit der Geschwindigkeit von 1,5 mm/a. Die Korrosionsgeschwindigkeit des Chroms war noch höher. Dagegen korrodierten Stellite 6 und Glanzkohlenstoff mit Geschwindigkeiten < 2 μm/a.
The corrosion behavior of stainless steels and copper alloys exposed to natural seawater
Authors: Little Brenda J. , Mansfeld Florian B.
Published: August 2016

The corrosion behavior of stainless steels, titanium and copper alloys exposed to flowing Pacific Ocean water was characterized using surface analytical and electrochemical techniques. Biofilm formation on stainless steels and titanium resulted in thin films of bacteria and diatoms that did not cause significant changes of the corrosion potential (Ecorr) or surface properties. Rotating cylinder experiments indicated that both Ecorr and corrosion rates for stainless steels and titanium were independent of mass transport. Four surface layers were identified on copper‐containing materials: substratum metal; an inorganic chloride corrosion layer that contained alloying elements; a biofilm; and crystalline, spherical phosphate‐rich deposits. All copper surfaces were colonized by bacteria independent of alloy composition. The complexity of the impedance spectra for copper‐containing materials was attributed to formation of surface layers and contributions of charge transfer and mass transport controlled reactions mediated by the layers. Both anodic and cathodic reactions for copper‐based materials were affected by mass transport.
Corrosion of synthetic metals
Authors: Beck Fritz , Michaelis Ronald
Published: August 2016

Intrinsically conducting polymers as polypyrrole or polythiophene are new materials which have found widespread interest in the last ten years. Acceptor type doping leads to a solid, which is well comparable to graphite salts. For any kind of practical application of these polymers, the problem of adequate long term stability under environmental conditions must be solved. There are only a few measurements of conductivity vs. time in the air to derive conclusions in this direction, e.g. for polypyrrole. For the first time we present results of a systematic research into the understanding of corrosion phenomena, which occur in aqueous eletrolytes at different pH. Polypyrrole is selected as a well established candidate for a synthetic metal. Layers at a nominal thickness of 10μm on platinum, doped with BF4− anions, were investigated in aqueous buffers in the pH‐range of 1–13. Corrosion was determined via the measurement of the residual redox capacities. The material corroded after a rapid electrochemical mechanism and a relatively slow chemical mechanism. Both processes involve the radical cationic centers (polarons) in the solid. The time constants varied from 102 to > 108 s. Our findings allow for a better understanding of corrosion and selfdischarge of polypyrrole. Other conducting polymers were found to corrode after the same mechanism.
Influence of surface treatment on the photoelectrochemical behaviour of Y‐Ba‐Cu‐O thin films
Authors: Hampel M. , Grabner E. W. , Jabs T. , Strehblow H.‐H.
Published: August 2016

Y‐Ba‐Cu‐O films with different surface treatments have been studied by photoelectrochemical and XPS measurements. The influence of etching by bromine in ethanol of these films has been followed by means of the electrochemical oxidation of ferrocene in an aprotic electrolyte. From the dependence of dark and photocurrent on etching time it is concluded that Y‐Ba‐Cu‐O thin films on LaAlO3 are covered by a 1, 1nm thick nonstoichiometric surface layer. The cathodic polarization of Y‐Ba‐Cu‐O at ‐0,9 V vs. Ag/AgCl in acetonitrile/0,1 M lithium perchlorate leads to the formation of a lithium‐containing, oxygen‐enriched surface layer. The photoelectrochemical response of the reduced films is similar to that of cuprous oxide and passive layers on copper.
Microfluidic Studies of Polymer Adsorption in Flow
Authors: Salari Alinaghi , Kumacheva Eugenia
Published: August 2016

Adsorption of polymer molecules under flow conditions governs a broad range of desired or undesired phenomena and has a broad range of applications. Microfluidic platforms integrated with analytical instrumentation offer the capability to study polymer adsorption in flow in a time‐ and labour‐efficient manner. Precise control of the microchannel dimensions and flow parameters enables accurate control of shear forces imposed on polymer solutions and on the molecules deposited on the surface, along with high sensitivity, enhanced reliability, and low reagent consumption. This review highlights recent advances in theoretical and experimental microfluidic studies of polymer immobilization under flow conditions in three area, namely, biosensing, biofouling, and studies of thrombosis and hemostasis.

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Light‐Induced Bulk Architecturation of PDMS Membranes
Authors: Stricher Arthur , Rinaldi Renaud G. , Machado Guilherme , Chagnon Gregory , Favier Denis , Chazeau Laurent , Ganachaud François
Published: August 2016

One major challenge of biomaterial engineering is to mimic the mechanical properties of anisotropic, multifunctional natural soft tissues. Existing solutions toward controlled anisotropy include the use of oriented reinforcing fillers, with complicated interface issues, or UV‐curing processing through patterned masks, that makes use of harmful photosensitive molecules. Here, a versatile process to manufacture biocompatible silicone elastomer membranes by light degradation of the platinum catalyst prior to thermal cross‐linking is presented. The spatial control of network density is demonstrated by experimental and theoretical characterizations of the mechanical responses of patterned cross‐linked membranes, with a view to mimic advanced implantable materials.

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Reversible Deactivation Radical Polymerization of Monomers Containing Activated Aziridine Groups
Authors: McLeod David C. , Tsarevsky Nicolay V.
Published: August 2016

Polymers bearing activated aziridine groups are attractive precursors to α‐substituted‐β‐amino‐functionalized materials due to the enhanced reactivity of the pendant aziridine functionalities toward ring‐opening by nucleophiles. Two aziridine‐containing styrenic monomers, 2‐(4‐vinylphenyl)aziridine (VPA) and N‐mesyl‐2‐(4‐vinylphenyl)aziridine (NMVPA), were polymerized under a variety of reversible deactivation radical polymerization conditions. Low‐catalyst‐concentration atom transfer radical polymerization (LCC‐ATRP) and reversible addition‐fragmentation chain‐transfer (RAFT) polymerization were ineffective at producing well‐defined polymers from VPA due to side reactions between the aziridine functionalities and the agents controlling the polymerizations (catalysts or chain transfer agents). PolyVPA produced under nitroxide‐mediated polymerization (NMP) conditions had narrow molecular weight distribution at low to moderate conversions of monomer, but branched and eventually cross‐linked polymers were formed at higher conversions due to ring‐opening reactions of the aziridine groups. Most of these undesirable side reactions were eliminated by attaching a methanesulfonyl (mesyl) group to the aziridine nitrogen atom, and well‐defined linear homopolymers with targeted molecular weights were realized from NMVPA under RAFT and NMP conditions; however, side reactions between the aziridine groups and the catalyst in LCC‐ATRP still occured and the polymerization was uncontrolled using this technique.

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Fabrication and Characterization of Completely Biodegradable Copolyester–Chitosan Blends: I. Spectroscopic and Thermal Characterization
Authors: Pokhrel Shanta , Lach Ralf , Le Hai Hong , Wutzler André , Grellmann Wolfgang , Radusch Hans‐Joachim , Dhakal Rabindra P. , Esposito Antonella , Henning Sven , Yadav Paras N. , Saiter Jean M. , Heinrich Gert , Adhikari Rameshwar
Published: August 2016

Chitosan was prepared from shells of locally available fresh water prawns with variation of sodium hydroxide concentration and reaction time. The biopolymer was melt‐mixed with a commercially available biodegradable polymer, the poly(butylene adipate‐co‐terephthalate) (PBAT). The chitosan and blend films were characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The glass transition temperature (Tg) and melting point of the materials remained unchanged implying complete incompatibility of the blend components. Kinetic study showed that activation energy of the degradation process, i.e., thermal stability of the blends, decreased with increasing chitosan content in the blends. As the thermal properties of all the samples were found to be identical, it can be concluded that there was no effect of the added chitosan on the crystallization and melting behavior of the PBAT. These findings support the notion of the absence of interactions among the blend components. The rate of biodegradation was found to be higher in blends compared to pure PBAT polymer.
Silver Nanoparticle Entrapped Calcium‐Alginate Beads for Fe(II) Removal via Adsorption
Authors: Asthana Anupama , Verma Renu , Singh Ajaya Kumar , Susan Md. Abu Bin Hasan , Adhikari Rameshwar
Published: August 2016

Silver nanoparticle entrapped calcium‐alginate beads (AgNP‐CAB) were successfully synthesized as adsorbent for effective removal of Fe(II) ions from aqueous solution. The adsorbent was characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), X‐ray diffraction (XRD) and thermogravimetric analysis (TGA). Batch adsorption experiments were used to determine the adsorption capacity. The influence of various factors (such as temperature, pH, adsorbent dosage and contact time) on adsorption behaviour was investigated. The adsorbent thus developed showed higher uptake at pH 4, and adsorption the capacity decreased with increasing temperature. The kinetic results for the adsorption process were interpreted using pseudo‐first order and pseudo‐second order rate equations, as well as Elovich and intra‐particle diffusion models. A good correlation with the pseudo‐second order rate kinetics (R2 = 0.998) could be observed. Adsorption isotherms were fitted to Langmuir, Freundlich, Temkin and Harkins–Jura isotherms whereby the experimental data was found to best fitted for the Langmuir model. The maximum adsorption capacity of adsorbent was found to be 236.40 mg/g.
Bone Fracture: Parallels to Polymer Fatigue
Authors: Klehm Jessica , Henning Sven , Adhikari Rameshwar , Brandt Jörg
Published: August 2016

Based on electron microscopic investigations, initial stages of microcrack formation and growth in bone are described as craze‐like phenomena. The comparison of micro‐ and nanoscopic processes of deformation and fracture induced under different experimental conditions give rise to the conclusion that crazing is a fundamental micromechanical process during bone damage and fracture. Although there are striking similarities to crazes in polymeric materials, craze formation and growth in bone is strongly influenced by the morphology of the main building blocks of the bone matrix, i.e., the mineralized collagen fibrils, as well as by the significant anisotropy of bone architecture.
Global regularity for a two‐dimensional nonlinear Boussinesq system
Authors: Qin Yuming , Su Xing , Wang Yang , Zhang Jianlin
Published: August 2016

In this paper, we first utilize the vanishing diffusivity method to prove the existence of global quasi‐strong solutions and get some higher order estimates, and then prove the global well‐posedness of the two‐dimensional Boussinesq system with variable viscosity for H3 initial data. Copyright © 2016 John Wiley & Sons, Ltd.
Renal ischemia and reperfusion assessment with three‐dimensional hyperpolarized 13C,15N2‐urea
Authors: Nielsen Per Mose , Szocska Hansen Esben Søvsø , Nørlinger Thomas Stokholm , Nørregaard Rikke , Bonde Bertelsen Lotte , Stødkilde Jørgensen Hans , Laustsen Christoffer
Published: August 2016

Purpose

The aim of this work was to investigate whether hyperpolarized 13C,15N2‐urea can be used as an imaging marker of renal injury in renal unilateral ischemic reperfusion injury (IRI), given that urea is correlated with the renal osmotic gradient, which describes the renal function.

Methods

Hyperpolarized three‐dimensional balanced steady‐state 13C magnetic resonance imaging (MRI) experiments alongside kidney function parameters and quantitative polymerase chain reaction measurements were performed in rats subjected to unilateral renal ischemia for 60‐minute and 24‐hour reperfusion.

Results

We revealed a significant reduction in the intrarenal gradient in the ischemic kidney in agreement with cortical injury markers neutrophil gelatinase‐associated lipocalin and kidney injury molecule 1, as well as functional kidney parameters.

Conclusion

Hyperpolarized functional 13C,15N2 urea MRI can be used to successfully detect changes in the intrarenal urea gradient post‐IRI, thereby enabling in vivo monitoring of the intrarenal functional status in the rat kidney. Magn Reson Med 76:1524–1530, 2016. © 2016 International Society for Magnetic Resonance in Medicine
A Community‐Engaged Assessment of Barriers and Facilitators to Rapid Stroke Treatment
Authors: Nemeth Lynne S. , Jenkins Carolyn , Jauch Edward C. , Conway Sharon , Pearlman Adam , Spruill Ida J. , Brown Lynette J. , Linnen Joyce , Linnen Florene , Andrews Jeannette O.
Published: August 2016

Treatment for acute ischemic stroke must be initiated within hours of stroke symptom onset, and the sooner it is administered, the better. In South Carolina, 76% of the population can access expert stroke care, and rural hospitals may provide specialized treatment using telemedicine, but many stroke sufferers seek care too late to achieve full benefit. Using a community‐engaged approach in a southern rural community, we explored barriers and facilitators to early stroke care and implications for improvement. The Community‐Engaged Assessment to facilitate Stroke Elimination (CEASE) study was guided by a community advisory group to ensure community centeredness and local relevance. In a qualitative descriptive study, eight focus groups were conducted including 52 individuals: recent stroke survivors, family members, emergency medical personnel, hospital emergency department staff, primary care providers, and community leaders. From analysis of focus group transcripts came six themes: lack of trust in healthcare system and providers; weak relationships fueled by poor communication; low health literacy; financial limitations related to health care; community‐based education; and faith as a message of hope. A hierarchy model for improving early community‐based stroke care was developed through consensus dialogue by community representatives and the research team. This model can be used to inform a community‐partnered, stakeholder‐informed intervention to improve stroke care in a rural southern community with the goal of improving stroke education, care, and outcome. © 2016 Wiley Periodicals, Inc.
Validation of the Chinese Version of the Functional Outcomes of Sleep Questionnaire‐10 in Pregnant Women
Authors: Tsai Shao‐Yu , Shun Shiow‐Ching , Lee Pei‐Lin , Lee Chien‐Nan , Weaver Terri E.
Published: August 2016

We evaluated the psychometric properties of a Mandarin Chinese version of the Functional Outcomes of Sleep Questionnaire‐10 (FOSQ‐10) in pregnant women. A total of 228 first‐trimester pregnant women participated in the study, which was conducted in an outpatient obstetric clinic at a medical center in Taipei, Taiwan. The Chinese version of the FOSQ‐10 demonstrated satisfactory internal consistency (Cronbach alpha = .85), adequate corrected item‐total correlations (from .40 to .67), and acceptable test–retest reliability over 7 days (ICC = .73). Construct validity was supported by exploratory factor analysis showing a one‐factor structure with item loadings between .49 and .77. Significant associations with the Medical Outcomes Study Short‐Form Health Survey 12 version 2 and Pittsburgh Sleep Quality Index supported criterion‐related and convergent validity. Significant differences in the Chinese version of the FOSQ‐10 total scores were found between women with clinically significant daytime sleepiness and those without, suggesting adequate discriminant validity. Ceiling effects were observed for all items, but no floor or ceiling effects were found for total scores. Findings suggest that the Chinese version of the FOSQ‐10 is a valid and reliable instrument to identify important effects of sleep‐related impairment in Chinese women during pregnancy. Further testing is needed in more diverse pregnant women, such as women with complicated pregnancies and those with sleep disorders. © 2016 Wiley Periodicals, Inc.
Preparation and characterization of microcapsules containing particulate phosphorescent agent with suspension polymerization
Authors: Taguchi Yoshinari , Ito Daisuke , Saito Natsukaze , Kimura Isao , Tanaka Masato
Published: August 2016

Microcapsules containing particulate phosphorescent agent (strontium aluminate) were prepared by the suspension polymerization method and characterized about a few items such as the mean diameters, the content, the inner structure and the afterglow luminance property. Furthermore, the fundamental experiments were conducted to investigate how the dispersing feature of particulate phosphorescent agent affects the afterglow luminance property. In the experiment, the concentration of oil soluble surfactant, the crosslinking agent species, the added weight of the phosphorescent agent and the pre‐bulk polymerization time were mainly changed stepwise. Afterglow luminance of particulate phosphorescent agent gradually decreased with the afterglow time and considerably decreased because of soaking them in water. Decline of afterglow luminance because of soaking in water could be prevented by microencapsulation. Afterglow luminance of the multicore type microcapsules was found to be higher than that of the core–shell type microcapsules. The content of particulate phosphorescent agent could be increased by performing pre‐bulk polymerization and increasing the concentration of the oil soluble surfactant. Copyright © 2016 John Wiley & Sons, Ltd.
Nanoclay reinforced polyethylene composites: Effect of different melt compounding methods
Authors: Boran Sevda , Kiziltas Alper , Erbas Kiziltas Esra , Gardner Douglas J. , Rushing Todd S.
Published: August 2016

Nanoclay (NC) reinforced high‐density polyethylene (HDPE) composites were prepared by different melt compounding methods using (1) a single screw extruder (SSE), (2) twin screw extruder (TSE), (3) a combination of SSE and extensional flow mixer (EFM), and (4) a bowl mixer masterbatch method (MB). PE‐grafted maleic anhydride (PE‐g‐MA) was used as a compatibilizer. EFM increased complex melt viscosity (η*) of the HDPE/NC composites as compared to the neat HDPE and also provided a better interaction between HDPE and NC to create slightly lower melt η* as compared to MB and PE‐g‐MA composites. The low viscosity melt behavior of the pure HDPE changes to more solid like melt behavior in the PE‐g‐MA HDPE/NC composites in the low frequency (ω) region. PE‐g‐MA + EFM method exhibited better impact strength compared to the other HDPE/NC composites. Using the PE‐g‐MA and masterbatch compounding methods had a beneficial role in improving mechanical properties. POLYM. ENG. SCI., 57:324–334, 2017. © 2016 Society of Plastics Engineers
Comparison of Fresh‐Frozen Plasma, Four‐Factor Prothrombin Complex Concentrates, and Recombinant Factor VIIa to Facilitate Procedures in Critically Ill Patients with Coagulopathy from Liver Disease: A Retrospective Cohort Study
Authors: Kwon Jennifer O. , MacLaren Robert
Published: August 2016

Study Objective

To evaluate fresh‐frozen plasma (FFP), four‐factor prothrombin complex concentrates (PCCs), and recombinant factor VIIa (rFVIIa) for lowering international normalized ratio (INR) and facilitating procedures in critically ill patients with hepatic impairment.

Design

Retrospective cohort study.

Setting

Intensive care units at a large university‐affiliated teaching hospital.

Patients

Forty‐five adults with hepatic impairment who were admitted between September 1, 2011, and December 31, 2015, and had an admission INR of 1.5 or greater, required an invasive intervention or minor surgical procedure, and received FFP alone (15 patients), PCCs (15 patients), or rFVIIa (15 patients).

Measurements and Main Results

The primary outcomes were rates of achieving an INR less than 1.5 at the time of the procedure and an absolute change in INR from 12 hours before the procedure to the time of the procedure. Secondary outcomes were the time to the procedure, blood product use, bleeding rates, and adverse events. The mean ± SD doses of FFP, PCCs, and rFVIIa were 1.1 ± 0.5 units, 2523 ± 861 units, and 2.6 ± 0.9 mg, respectively, administered 2.1 ± 1.4 hours (p<0.05, FFP vs PCCs or rFVIIa), 1.3 ± 0.5 hours, and 1.3 ± 0.6 hours before the procedure, respectively. Achieving an INR less than 1.5 was more likely to occur with PCCs (80%, p=0.03) and rFVIIa (87%, p=0.01) compared with FFP (27%). INR reduction was greater with PCCs (1.6 ± 0.9, p<0.05) and rFVIIa (1.8 ± 0.7, p<0.01) compared with FFP (0.5 ± 0.8). Use of blood products (FFP, cryoprecipitate, packed red blood cells, and platelets) was significantly greater in the FFP group both before and after the procedural intervention. Hypervolemia was less likely to occur in the PCCs (40%, p=0.02) or rFVIIa (33%, p<0.01) groups than in the FFP group (93%). Overall, 33 (73%) of the 45 patients experienced minor bleeding. Three patients (7%) experienced clotting of a central line or dialysis filter, and all were in the PCCs or rFVIIa groups.

Conclusion

Unlike FFP, PCCs and rFVIIa effectively and safely reduced INR in critically ill patients with coagulopathy associated with liver impairment to expedite interventions. The amount of blood products used was significantly lower in the PCC and rFVIIa groups, possibly reducing the risk of hypervolemia. Bleeding rates, however, were similar across groups.
Rivaroxaban versus Heparin Bridging to Warfarin Therapy: Impact on Hospital Length of Stay and Treatment Costs for Low‐Risk Patients with Pulmonary Embolism
Authors: Weeda Erin R. , Kohn Christine G. , Peacock W. Frank , Fermann Gregory J. , Crivera Concetta , Schein Jeff R. , Coleman Craig I.
Published: August 2016

Study Objective

To compare hospital length of stay (LOS) and hospital treatment costs in low‐risk patients with pulmonary embolism (PE) anticoagulated with rivaroxaban or heparin bridging to warfarin therapy.

Design

Retrospective review of electronic health records and hospital billing records.

Setting

Large, teaching hospital in the northeastern United States.

Patients

One hundred ninety adults with objectively confirmed acute PE presenting to the emergency department between November 1, 2012, and May, 12, 2015, who were classified as low risk of early mortality and received anticoagulation with either rivaroxaban or heparin (i.e., unfractionated heparin or low‐molecular‐weight heparin) bridging to warfarin therapy were included in the analysis. Patients were identified as low risk by at least one of the following prediction rules: simplified Pulmonary Embolism Severity Index (sPESI; 115 patients), Hestia criteria (87 patients), or In‐hospital Mortality for Pulmonary Embolism using Claims Data (IMPACT; 108 patients); these were not mutually exclusive, as patients could be classified as low risk by more than one risk stratification tool.

Measurements and Main Results

We divided low‐risk patients identified by each prediction rule into two cohorts: those receiving rivaroxaban (allowing ≤ 2 days of prior heparin use) or heparin bridging to warfarin therapy. The primary end points for this study were LOS (number of days from the patient's arrival at our institution until discharge) and total hospital treatment costs (our institution's actual costs to provide treatment) for the index PE hospital encounter. Using multivariable generalized linear model regression (gamma‐distributed error and log‐link), we estimated differences in LOS and hospital costs (in 2015 U.S. dollars) between the two cohorts after covariate adjustment. Rivaroxaban was associated with significantly shorter adjusted LOS (range −2.1 to −4.3 days) and significantly lower index hospital costs (range −$3835 to −$7094) versus heparin bridging to warfarin, regardless of the prediction rule used to identify low‐risk patients.

Conclusion

Among low‐risk PE patients identified by using sPESI, Hestia or IMPACT, rivaroxaban was associated with significantly shorter LOS and lower hospital treatment costs versus heparin bridging to warfarin.
ProteinProcessor: A probabilistic analysis using mass accuracy and the MS spectrum
Authors: Epstein Jonathan A. , Blank Paul S. , Searle Brian C. , Catlin Aaron D. , Cologna Stephanie M. , Olson Matthew T. , Backlund Peter S. , Coorssen Jens R. , Yergey Alfred L.
Published: August 2016

Current approaches to protein identification rely heavily on database matching of fragmentation spectra or precursor peptide ions. We have developed a method for MALDI TOF‐TOF instrumentation that uses peptide masses and their measurement errors to confirm protein identifications from a first pass MS/MS database search. The method uses MS1‐level spectral data that have heretofore been ignored by most search engines. This approach uses the distribution of mass errors of peptide matches in the MS1 spectrum to develop a probability model that is independent of the MS/MS database search identifications. Peptide mass matches can come from both precursor ions that have been fragmented as well as those that are tentatively identified by accurate mass alone. This additional corroboration enables us to confirm protein identifications to MS/MS‐based scores that are otherwise considered to be only of moderate quality. Straightforward and easily applicable to current proteomic analyses, this tool termed “ProteinProcessor” provides a robust and invaluable addition to current protein identification tools.
Qigong/tai chi for sleep and fatigue in prostate cancer patients undergoing radiotherapy: a randomized controlled trial
Authors: McQuade Jennifer L. , Prinsloo Sarah , Chang David Z. , Spelman Amy , Wei Qi , Basen‐Engquist Karen , Harrison Carol , Zhang Zonghao , Kuban Debra , Lee Andrew , Cohen Lorenzo
Published: August 2016

Objectives

Sleep disturbances and fatigue are common in prostate cancer patients undergoing radiotherapy. Prior research suggests mind‐body techniques may improve these outcomes. We conducted a randomized controlled trial of qigong/tai chi (QGTC) in men with prostate cancer undergoing radiotherapy.

Methods

Men with prostate cancer starting definitive radiation were randomized to 1 of 3 groups: (1) QGTC; (2) light exercise (LE); or (3) waiting list control. Sleep disturbances (Pittsburgh Sleep Quality Index) and fatigue (Brief Fatigue Inventory) were assessed at baseline, midway through radiotherapy (T2), during the last week of radiotherapy (T3), and at 1 (T4) and 3 months (T5) after the end of radiotherapy. Patients in the QGTC and LE groups attended three 40‐minute classes per week throughout radiotherapy.

Results

Ninety patients were randomized to the 3 groups (QGTC = 26; LE = 26; waiting list control = 24). The QGTC group reported longer sleep duration midway through radiotherapy (QGTC = 7.01 h; LE = 6.42; WL = 6.50; P = .05), but this difference did not persist over time. There were no group differences in other domains of sleep or fatigue. Exploratory analyses conducted to examine the effect of health‐related quality of life (Expanded Prostate Cancer Index Composite and American Urological Association Symptom score) on sleep and fatigue showed significant correlations across multiple domains.

Conclusions

Qigong/tai chi during radiation for prostate cancer resulted in superior sleep duration midway through radiation, but this effect was not durable, and there were no differences in other domains of sleep or fatigue. Exploratory analysis demonstrated that both sleep and fatigue were highly correlated with prostate cancer–related physical symptoms. Future mind‐body intervention studies should incorporate multimodal therapy focused on improving physical symptoms in this population.
Reduce litigation, legal costs in 3 simple steps
Authors: Charmatz Marc
Published: August 2016

Your college or university can take three simple steps to help prevent litigation under the Americans with Disabilities Act and/or Section 504 of the Rehabilitation Act, or at the very least avoid exposure to high damages and attorney's fees awards.
An efficient group key agreement protocol for secure P2P communication
Authors: Vijayakumar Pandi , Naresh Ramu , Jegatha Deborah Lazarus , Hafizul Islam SK
Published: August 2016

The efficient design of a distributed group key management for a peer to peer (P2P) network with minimal computation complexity in dynamic secure group communication is a challenging issue. This is because of the absence of a centralized coordinator. In order to provide this facility, a self‐composed distributed group key management framework is proposed for secure P2P communication. In this proposed work, group key computation is performed using Chinese remainder theorem and secure communication is performed through RSA encryption algorithm. This self‐composed key management is a one round protocol in which a shared group key is generated using the public key of each individual user, and it is derived from the respective private key. The main advantage of the group key management scheme proposed in this paper is that it reduces the computation complexity of the peer users to O(1). This reduction in computation complexity is achieved by performing one addition and multiplication operation during a single member join and one subtraction operation during a single member leave operation. The proposed algorithm has been implemented and analyzed with well‐known existing distributed group key management protocols and observed that it reduces the computation complexity significantly. Copyright © 2016 John Wiley & Sons, Ltd.
A Bayesian adaptive phase I–II trial design for optimizing the schedule of therapeutic cancer vaccines
Authors: Cunanan Kristen M. , Koopmeiners Joseph S.
Published: August 2016

Phase I–II clinical trials refer to the class of designs that evaluate both the safety and efficacy of a novel therapeutic agent in a single trial. Typically, Phase I–II oncology trials take the form of dose‐escalation studies, where initial subjects are treated at the lowest dose level and subsequent subjects are treated at progressively higher doses until the optimal dose is identified. While dose‐escalation designs are well‐motivated in the case of traditional chemotherapeutic agents, an alternate approach may be considered for therapeutic cancer vaccines, where an investigator's main objective is to evaluate the safety and efficacy of a set of dosing schedules or adjuvant combinations rather than to compare the safety and efficacy of progressively higher dose levels. We present a two‐stage, Bayesian adaptive Phase I–II trial design to evaluate the safety and efficacy of therapeutic cancer vaccines. In the first stage, we determine whether a vaccination schedule achieves a minimum level of performance by comparing the toxicity and immune response rates to historical benchmarks. Vaccination schedules that achieve a minimum level of performance are compared using their magnitudes of immune response. If the superiority of a single schedule cannot be established after the first stage, Bayesian posterior predictive probabilities are used to determine the additional sample size required to identify the optimal vaccination schedule in a second stage. Copyright © 2016 John Wiley & Sons, Ltd.
Structural, Optical Characterization and Growth Mechanism of Kadamba Flower like ZnO Nanocrystals Synthesized by a Simple Chemical Route.
Authors: Kundu Samapti , Sain Sumanta , Kar Tanusree , Pradhan Swapan K.
Published: August 2016

Kadamba‐flower like morphology of ZnO nanocrystals (NCs) has been synthesized at room temperature by a wet chemical route without using any template or capping agent. Growth mechanism of these NCs has been proposed based on detailed structural and microstructural interpretations by analyzing X‐ray diffraction (XRD) patterns employing Rietveld refinement method and FESEM/HRTEM images. FESEM images clearly reveal that the flower like 3D morphology transforms gradually to thin layer like 2D network of ZnO nanorods (NRs) (petals) with increase in chemical reaction time. Chemical composition of these flowers has been obtained from the energy dispersive X‐ray (EDX) spectroscopy. It is noticed that the John‐Teller (JT) distortion in ZnO4 tetrahedron within the hexagonal ZnO lattice gradually diminishes to zero with increasing wet chemical reaction time and the hydroxyl group plays an important role during the growth of ZnO nanoflowers. Change in optical band gap of ZnO due to morphological transformation is ascertained from the UV‐Vis spectrum analysis. PL spectrum reveals the content of excess oxygen in ZnO nanoflower which has also been estimated from Rietveld refinement of XRD data.
Adsorption Separation of R‐22, R‐32 and R‐125 Fluorocarbons using 4A Molecular Sieve Zeolite
Authors: Wanigarathna DarshikaK. J. A. , Gao Jiajian , Takanami Tetsuo , Zhang Qichun , Liu Bin
Published: August 2016

Global warming has received great attention over the past decades, which is having costly impacts on our communities, health and climate. Fluorocarbon derivatives that are widely used in various industries such as refrigerants and solvents have significant effect on global warming due to their high global warming potential. Recycling and reuse of fluorocarbons help not only to minimize the environmental release but also to fulfill the future demand with the rapid phase out of some of the fluorocarbons. Herein, our work reports the adsorption separation of mixtures of difluoromethane (R‐32), chlorodifluoromethane (R‐22) and pentafluoroethane (R‐125) into their pure components using 4A molecular sieve zeolite under ambient conditions. Pure gas equilibrium isotherm measurements indicate that the uptake capacity follows the order of R‐32 > R‐22 > R‐125 on 4A zeolite with negligible uptake capacity for R‐125. As evidenced by the gas breakthrough results, R‐32, R‐22 and R‐125 could be successfully separated into pure components using 4A zeolite. Steric effects were responsible for the separation of R‐32 and R‐22 from R‐125 while slower uptake rate of R‐22 compared to R‐32 facilitated the successful separation of R‐22 from R‐32. The regular pore structure, excellent match of pore size of 4A zeolite with the molecular sizes of the fluorocarbon make the product gases very pure, to the extent of direct industrial applications.
A Facile Approach towards Fabrication of GdB6‐ZnO Heteroarchitecture as High Current Density Cold Cathode
Authors: Suryawanshi Sachin R. , Mistari Chetan D. , Singh Anil K. , Phase Deodatta M. , Late Dattatray J. , Sinha Sucharita , More Mahendra A.
Published: August 2016

Three dimensional (3D) GdB6‐ZnO heteroarchitecture comprised of thin coating of GdB6 on self aligned ZnO urchins with pointed apex has been synthesized employing optimized Pulsed Laser Deposition (PLD) technique. The self aligned ZnO urchins on Zn substrate were obtained using hydrothermal route. The as‐synthesized GdB6‐ZnO heteroarchitecture was characterized using XRD, SEM, TEM XPS, and UPS in order to reveal its structural, morphological, chemical, and electronic properties. Interestingly, the GdB6‐ZnO heteroarchitecture exhibits superior field emission (FE) behviour in contrast to the pristine ZnO urchins envisaged by extraction of very high emission current density of ∼ 4.6 mA/cm2 at an applied field of ∼ 4.5 V/μm, against ∼1.5 mA/cm2 at an applied field of ∼ 5.6 V/μm from the pristine ZnO urchins emitter. Furthermore, the GdB6‐ZnOemitter exhibits good emission stability at pre‐set value of ∼5 μA over duration of more than 3 hours. The superior FE behaviour of the GdB6‐ZnO is attributed to low workfunction of GdB6 and presence of nanometric protrusions on the emitter surface, further enhancing the aspect ratio provided by the ZnO urchins. The present results demonstrate a facile approach towards fabrication of high current density cold cathodes due to rare earth hexaborides via designing heteroarchitectures comprised of their well adherent ultrathin coating on high aspect ratio metal oxide nanostructures.
Synthesis and Characterization of Bis(sigma)borate and Bis–zwitterionic Complexes of Rhodium and Iridium
Authors: Roy Dipak Kumar , Borthakur Rosmita , De Anangsha , Varghese Babu , Phukan Ashwini K. , Ghosh Sundargopal
Published: August 2016

Building upon the chemistry of Rh–N,S‐heterocyclic carbene complex, [(Cp*Rh)(L2)(1‐benzothiazol‐2‐ylidene)], 2 (Cp*=η5‐C5Me5; L=C7H4NS2) with various monoboranes‐Lewis adducts, we explored the chemistry of 2 with BH3⋅thf at elevated temperature. As a result, mild thermolysis of 2 with BH3⋅thf led to the formation of bis(sigma)borate [(η4‐C5Me5H)Rh(η2‐H3BL)], 3 and a bis‐zwitterionic species [Cp*RhS(BH2L2)], 4 with the concomitant release of BH3⋅bt (bt=benzothiazole). The RhS3C2N2B2 atoms in 4 generates two six membered rings fused by a common Rh−S bond, which may be considered as a bicycle [4.4.0] cage at the rhodium center. In an effort to generate the iridium analogue of 3, reaction of [Cp*IrCl2]2 with Na[H3B(mbt)] (mbt=2‐mercaptobenzothiazole) was carried out that produced bis(sigma)borate complex [(η4‐C5Me5H)Ir(η2‐H3BL)], 1. The solid state X‐ray structures of 1 and 3 showed that the Cp*H ligand coordinated to the metal center in a η4‐fashion. In compound 3, the methyl group is oriented towards rhodium center, whereas it is away from Ir center in 1. In addition, the DFT computations were performed to shed light on the bonding and electronic structures of these compounds.