bluuebunny/crossref_metadata_2025 huggingface dataset:
Thermoplastic Healing in Epoxy Networks: Exploring Performance and Mechanism of Alternative Healing Agents
Authors: Varley Russell J. , Craze David A. , Mouritz Adrian P. , Wang Chun H.
Published: April 2013

This paper investigates thermally activated healing in an epoxy amine network using six thermoplastic modifiers; ethylene vinyl acetate (EVA), poly (ethylene‐co‐glycidyl)‐methacrylate (PEGMA), poly(vinyl‐butyral) (PVB), styrene‐ethylene‐butadiene copolymer (SEBS), acrylonitrile‐butadiene‐styrene (ABS) and polyethylene‐co‐methacrylic acid (EMAA). They all exhibit healing but varied in efficiency, repeatability and mechanism. EMAA, PEGMA and EVA display superior healing or load recovery compared with ABS, SEBS and PVB with increasing healing events. For EMAA and PEGMA this is attributed to a pressure delivery mechanism, while for EVA, it is attributed to increased viscous flow and a highly elastomeric response to damage. Adhesive binding of the fracture surfaces is also critical in restoring load.

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Thermally Induced, Rapid Wettability Switching of Electrospun Blended Polystyrene/Poly(N‐Isopropylacrylamide) Nanofiber Mats
Authors: Muthiah Palanikkumaran , Boyle Timothy J. , Sigmund Wolfgang
Published: April 2013

The response time (to change from maximum to minimum contact angle—CA for a drop of water) on the electrospun poly(N‐isoporpylacrylamide) (PNIPA)/polystyrene (PS) fiber mats of 380, 990, and 1500 nm diameter fibers was found to be 4–5 s; whereas, on the 16 µm diameter fiber it was more than five times slower. While the reported switching times were limited by the experimental design, they are in the micro‐ to millisecond for fiber diameters ranging between 100 and 500 nm, in theory. The temperature‐dependent‐switch in CA values is attributed to the hydrogen bonding capability of PNIPA with water. The closer to superhydrophobic CA values at 65 °C was successfully described by the Cassie–Baxter (CB) state equation. The superhydrophilicity at RT was explained by hydrogen bonding as well as capillary forces provided by the fiber mat. The variations in the larger fibers' changes are attributed to lower surface area with reduced capillary driving forces for droplet spread.
On the global weak solutions for a modified two‐component Camassa‐Holm equation
Authors: Guan Chunxia , Yin Zhaoyang
Published: April 2013

In this paper, we investigate the existence of global weak solutions to the Cauchy problem of a modified two‐component Camassa‐Holm equation with the initial data satisfying limx → ±∞u0(x) = u±. By perturbing the Cauchy problem around a rarefaction wave, we obtain a global weak solution for the system under the assumption u− ≤ u+. The global weak solution is obtained as a limit of approximation solutions. The key elements in our analysis are the Helly theorem and the estimation of energy for approximation solutions in \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$H^1(\mathbb {R})\times H^1(\mathbb {R})$\end{document} and some a priori estimates on the first‐order derivatives of approximation solutions.
Bearing capacity of strip foundations reinforced with geogrid sheets by using upper bound finite‐element limit analysis
Authors: Kumar Jyant , Sahoo Jagdish Prasad
Published: April 2013

By using the upper bound finite‐elements limit analysis, with an inclusion of single and two horizontal layers of reinforcements, the ultimate bearing capacity has been computed for a rigid strip footing placed over (i) fully granular, (ii) cohesive‐frictional, and (iii) fully cohesive soils. It is assumed that (i) the reinforcements are structurally strong so that no axial tension failure can occur, (ii) the reinforcement sheets have negligible resistance to bending, and (iii) the shear failure can take place between the reinforcement and soil mass. It is expected that the different approximations on which the analysis has been based would generally remain applicable for reinforcements in the form of geogrid sheets. A method has been proposed to incorporate the effect of the reinforcement in the analysis. The efficiency factors, ηc and ηγ, to be multiplied with Nc and Nγ , for finding the bearing capacity of reinforced foundations, have been established. The results have been obtained (i) for different values of ϕ in case of fully granular and cohesive‐frictional soils, and (ii) for different rates at which the cohesion increases with depth for a fully cohesive soil. The optimum positions of the reinforcements' layers have also been determined. The effect of the reinforcements' length on the results has also been analyzed. As compared to cohesive soils, the granular soils, especially with higher values of ϕ, cause a much greater increase in the bearing capacity. The results compare reasonably well with the available theoretical and experimental data from literature. Copyright © 2013 John Wiley & Sons, Ltd.
The Development of Adolescent and Young Adult Participation Sort – Taiwanese Version
Authors: Hsin‐Yen Wang , Berg Christine
Published: April 2013

The purpose of this pilot research was to translate the Adolescent and Young Adult Participation Sort into Taiwanese (AYAPS‐T), an assessment tool measuring the activity participation and the self‐identified barriers of youth transitioning into adulthood. The study included five phases: translation, cultural adaptation, taking photographs, field testing for content validity and pilot testing of test–retest reliability. A literature review, expert review and translation with back‐translation were conducted for the initial activities. The activities were then edited on the basis of the feedback of 23Taiwanese youth for content validity. Test–retest reliability (intraclass correlation coefficient = 0.91) of the AYAPS‐T reported by 22 Taiwanese youth was high. With the activities designed to meet the developmental needs of young adults, the methodology of sorting photographs, the barrier list to identify possible obstacles and some psychometric properties established, the AYAPS‐T serves as a reliable and valid tool to identify engagement of young adults in their occupations. Because of the nature of a pilot study, results are limited by a small sample size and limited evidence of psychometric properties. Psychometric properties such as interrater reliability and internal consistency as well as construct validity and concurrent validity need to be tested on a larger sample size. Copyright © 2013 John Wiley & Sons, Ltd.
PLLA‐HA vs. PLGA‐HA characterization and comparative analysis
Authors: Albano Carmen , González Gema , Palacios Jordana , Karam Arquímedes , Covis María
Published: April 2013

The chemical, thermal, thermo‐mechanical, and morphology properties of poly(L‐lactide) (PLLA) and poly(D,L Lactide‐co‐glycolide) (PLGA) composites with 30% hydroxyapatite (HA) were evaluated. The composites were prepared employing the solvent casting technique. The degradation kinetic parameters were obtained using the Coats–Redfern integral method for the reaction order and the E2 function methodology to calculate the activation energy (Ea). The addition of HA to these polymers matrices increased their glass transition temperature. This was confirmed by differential scanning calorimetery and dynamic–mechanical–thermal analysis. Also, the presence of HA increased the crystallization temperature of PLLA, implying a nucleation effect. The PLLA‐HA and PLGA‐HA composites exhibited better thermal stability, higher decomposition temperature, and higher activation energy for the decomposition process than the neat polymers. Morphology and dispersion of the filler are highly responsible for the thermal and mechanical properties of the composites, the PLGA‐HA composites showed a well dispersion but no improvement on storage modulus was found. On the other hand, the storage modulus (E′) of PLLA‐HA was enhanced, with respect to the neat polymer, mainly at temperatures above the glass transition. POLYM. COMPOS., 34:1433–1442, 2013. © 2013 Society of Plastics Engineers
Polymer solar cells with inkjet‐printed doped‐PEDOT: PSS anode
Authors: De Girolamo Del Mauro Anna , Diana Rosita , Grimaldi Immacolata Angelica , Loffredo Fausta , Morvillo Pasquale , Villani Fulvia , Minarini Carla
Published: April 2013

In this article, we describe the development of poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS)‐based ink for the fabrication of indium tin oxide (ITO)‐free polymer solar cells (PSCs). The ink consisted of PEDOT:PSS, suitably doped with dimethyl sulfoxide (DMSO) in solution. The printed PEDOT:PSS showed electrical conductivity of 1000 S/cm and transparency around 85% in the visible range. Then, they were employed as anodes in ITO‐free polymer PSCs based on a bulk heterojunction of poly(3‐hexylthiophene) and [6,6]‐phenyl C61‐butyric acid methyl ester. The effects of surface treatments (O2 plasma, UV ozone) of glass substrates on the quality and morphology of the printed layer were investigated in order to improve the anode quality. The performances of the devices with printed polymeric anode were compared to the one realized depositing DMSO‐PEDOT:PSS by spin coating technique. The best cells performances were obtained by UV ozone treatment reaching a power conversion efficiency of 1.5%. POLYM. COMPOS., 34:1493–1499, 2013. © 2013 Society of Plastics Engineers
Vegetable fiber pre‐tensioning influence on the composites reinforcement
Authors: Širvaitienė A. , Jankauskaitė V. , Bekampienė P. , Norkaitis J.
Published: April 2013

The automated manufacturing of several complex shape composite parts simultaneously by compression and transfer molding method faces the problem of poor elastic properties of synthetic fibers, what leads to the insufficient depth of formed part and fiber breakage. Alternative to synthetic fibers, vegetable fibers have higher elasticity and lower impact on environment, but due to the lower fiber bulk integrity and orientation vegetable fibers have lower strength. However, fiber pre‐tension processes involved in various composite manufacturing routes could enhance the fibrous reinforcement orientation and increase tensile strength. Nevertheless, the influence of this method commonly is used to increase the flexural strength of the composites and its influence on the tensile properties of the composite was not studied. Thus, the aim of this work was to investigate vegetable fiber pre‐tensioning influence on the tensile and flexural properties of the composites. It was obtained that significant enhancement of flexural performance is caused by the residual compressive forces propagated in the matrix polymer, achieved only at high values of pre‐tension (approximately at 50–70% of the ultimate strength of the reinforcement), while even minimal pre‐tension load significantly increases the tensile strength of the composite. Thus, the pre‐tension technique is particularly effective in the case of vegetable fibers reinforced composite, whose properties after pre‐tension are comparable with the properties of glass fiber composites. POLYM. COMPOS., 34:1533–1537, 2013. © 2013 Society of Plastics Engineers
Dyspepsia: alarm symptoms, investigation and management
Authors: Fong Steven , Dunn Jason
Published: April 2013

Dyspepsia is a common symptom and the priority is to identify alarm signals that necessitate endoscopy referral. Our Drug review discusses its investigation, management and some new drug developments, followed by sources of further information.
Prescribing outside of a drug's licence: issues and implications
Authors: Chisholm Alison
Published: April 2013

The GMC recently published updated guidance on prescribing outside of a medication's licence. Here, we examine the drivers and implications for off‐label prescribing, with a particular focus on the issues surrounding the prescribing of bevacizumab in wet AMD.
Pine Oil Effects on Chemical and Thermal Injury in Mice and Cultured Mouse Dorsal Root Ganglion Neurons
Authors: Clark S. P. , Bollag W. B. , Westlund K. N. , Ma F. , Falls G. , Xie D. , Johnson M. , Isales C. M. , Bhattacharyya M. H.
Published: April 2013

A commercial resin‐based pine oil (PO) derived from Pinus palustris and Pinus elliottii was the major focus of this investigation. Extracts of pine resins, needles, and bark are folk medicines commonly used to treat skin ailments, including burns. The American Burn Association estimates that 500,000 people with burn injuries receive medical treatment each year; one‐half of US burn victims are children, most with scald burns. This systematic study was initiated as follow‐up to personal anecdotal evidence acquired over more than 10 years by MH Bhattacharyya regarding PO's efficacy for treating burns. The results demonstrate that PO counteracted dermal inflammation in both a mouse ear model of contact irritant‐induced dermal inflammation and a second degree scald burn to the mouse paw. Furthermore, PO significantly counteracted the tactile allodynia and soft tissue injury caused by the scald burn. In mouse dorsal root ganglion neuronal cultures, PO added to the medium blocked adenosine triphosphate‐activated, but not capsaicin‐activated, pain pathways, demonstrating specificity. These results together support the hypothesis that a pine‐oil‐based treatment can be developed to provide effective in‐home care for second degree burns. Copyright © 2013 John Wiley & Sons, Ltd.
Palbinone from Paeonia suffruticosa Protects Hepatic Cells via Up‐regulation of Heme Oxygenase‐1
Authors: Ha Do Thi , Phuong Tran Thi , Oh Joonseok , Bae KiHwan , Thuan Nguyen Duy , Na MinKyun
Published: April 2013

Paeonia suffruticosa has been traditionally employed for vitalizing blood circulation and alleviating liver and inflammatory diseases. The pathways by which palbinone (PB) isolated from P. suffruticosa mediates heme oxygenase‐1 (HO‐1) induction were investigated using the specific inhibitors for PI3K and mitogen activated protein kinases pathways. The effect of PB‐treatment on Nrf2 translocalization and HO‐1‐antioxidant response element (ARE) regulation was examined employing Western blot and luciferase assays. PB induced HO‐1 expression via the activation of Nrf2 in the hepatic cells, and ARE‐dependent genes were stimulated via the PB‐mediated Nrf2 activation. PB‐mediated HO‐1 expression could be involved with PI3K/Akt and ERK1/2 pathways. Our study suggests the mechanism by which PB induces HO‐1 expression in the hepatic cells. This might substantiate the traditional applications of P. suffruticosa for the treatment of oxidative stress‐related diseases including oxidant and inflammatory‐mediated vascular and liver diseases. Copyright © 2013 John Wiley & Sons, Ltd.
EFFECT OF A MAJOR FLOOD ON BREEDING AND HABITAT OF THE CRIMSON FINCH (NEOCHMIA PHAETON): A RIPARIAN SPECIALIST
Authors: Houston W. A. , Black R. L.
Published: April 2013

Riparian specialists, such as the Crimson Finch (Estrildidae: Neochmia phaeton), are vulnerable to declines in habitat quality, including alterations of flow regime associated with dam construction. Crimson Finches persisted and bred in substantial numbers following two large floods in the Isaac–Connors catchment in early 2008. Major flooding was not detrimental to nesting and breeding success, although the immediate post‐flood period was identified as a bottleneck in the availability of riparian grass seed. Crimson Finches nested at 16 m or more above the normal river level (compared with an average of 2–3 m elsewhere in Northern Australia); indicating that they have adapted to the extreme flood peaks in the Fitzroy River basin. The tall river‐associated grass Chionachne cyathopoda was a key habitat plant, retaining seed well into the dry season when most other grasses are expended. It also provided abundant seeds following floods, coinciding with peaks in abundance of dependent young finches. The adaptations of both Crimson Finches and Chionachne suggest that increased flooding, predicted by climate change, is unlikely to be a problem. In contrast, a proposed dam on the Connors River may be a threat. River regulation that reduces peaks of major floods may favour introduced riparian grasses over flood adapted native grasses such as Chionachne. Any change in the quantity of this species could be detrimental to persistence of Crimson Finches. Environmental managers should carefully consider the ecology of Chionachne when making decisions about river flows. Copyright © 2013 John Wiley & Sons, Ltd.
Multi‐instrument characterization of the surfaces and materials in microfabricated, carbon nanotube‐templated thin layer chromatography plates. An analogy to ‘The Blind Men and the Elephant’
Authors: Jensen David S. , Kanyal Supriya S. , Madaan Nitesh , Hancock Jared M. , Dadson Andrew E. , Vail Michael A. , Vanfleet Richard , Shutthanandan V. , Zhu Zihua , Engelhard Mark H. , Linford Matthew R.
Published: April 2013

We apply a suite of analytical tools to characterize materials created in the production of microfabricated thin layer chromatography plates. Techniques used include X‐ray photoelectron spectroscopy (XPS), valence band spectroscopy, time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) in both positive and negative ion modes, Rutherford backscattering spectroscopy (RBS), and helium ion microscopy. Materials characterized include: the Si(100) substrate with native oxide: Si/SiO2, alumina (35 nm) deposited as a diffusion barrier on the Si/SiO2: Si/SiO2/Al2O3, iron (6 nm) thermally evaporated on the Al2O3: Si/SiO2/Al2O3/Fe, the iron film annealed in H2 to make Fe catalyst nanoparticles: Si/SiO2/Al2O3/Fe(NP), and carbon nanotubes (CNTs) grown from the Fe nanoparticles: Si/SiO2/Al2O3/Fe(NP)/CNT. The Fe films and nanoparticles appear in an oxidized state. Some of the analyses of the CNTs/CNT forests appear to be unique: (i) the CNT forest appears to exhibit an interesting ‘channeling’ phenomenon by RBS, (ii) we observe an odd–even effect in the SIMS spectra of Cn‐ species for n = 1 – 6, with the n ≥ 6 ions showing a steady decrease in intensity, and (iii) valence band characterization of CNTs using X‐radiation is reported. Initial analysis of the CNT forest by XPS shows that it is 100 at.% carbon. After one year, only ca. 0.25 at.% oxygen is observed. The information obtained from the combination of the different analytical tools provides a more complete understanding of our materials than a single technique, which is analogous to the story of ‘The Blind Men and the Elephant’. The raw XPS and ToF‐SIMS spectra from this study will be submitted to Surface Science Spectra for archiving. Copyright © 2013 John Wiley & Sons, Ltd.
Hierarchically Nanoperforated Graphene as a High Performance Electrode Material for Ultracapacitors
Authors: Mhamane Dattakumar , Suryawanshi Anil , Unni Sreekuttan M. , Rode Chandrashekhar , Kurungot Sreekumar , Ogale Satishchandra
Published: April 2013

High performance is reported for a symmetric ultracapacitor (UC) cell made up of hierarchically perforated graphene nanosheets (HPGN) as an electrode material with excellent values of energy density (68.43 Wh kg−1) and power density (36.31 kW kg−1). Perforations are incorporated in the graphite oxide (GO) and graphene system at room temperature by using silica nanoparticles as template. The symmetric HPGN‐based UC cell exhibits excellent specific capacitance (Cs) of 492 F g−1 at 0.1 A g−1 and 200 F g−1 at 20 A g−1 in 1M H2SO4 electrolyte. This performance is further highlighted by galvanostatic charge–discharge study at 2 A g−1 over a large number (1000) of cycles exhibiting 93% retention of the initial Cs. These property features are far superior as compared to those of symmetric UC cells made up of only graphene nanosheets (GNs), i.e. graphene sheets without perforations. The latter exhibit Cs of only 158 F g−1 at 0.1 A g−1 and the cells is not stable at high current density.
Cell Surface Receptor Targeted Biomimetic Apatite Nanocrystals for Cancer Therapy
Authors: Iafisco Michele , Delgado‐Lopez Josè Manuel , Varoni Elena Maria , Tampieri Anna , Rimondini Lia , Gomez‐Morales Jaime , Prat Maria
Published: April 2013

Nanosized drug carriers functionalized with moieties specifically targeting tumor cells are promising tools in cancer therapy, due to their ability to circulate in the bloodstream for longer periods and their selectivity for tumor cells, enabling the sparing of healthy tissues. Because of its biocompatibility, high bioresorbability, and responsiveness to pH changes, synthetic biomimetic nanocrystalline apatites are used as nanocarriers to produce multifunctional nanoparticles, by coupling them with the chemotherapeutic drug doxorubicin (DOXO) and the DO‐24 monoclonal antibody (mAb) directed against the Met/Hepatocyte Growth Factor receptor (Met/HGFR), which is over‐expressed on different types of carcinomas and thus represents a useful tumor target. The chemical‐physical features of the nanoparticles are fully investigated and their interaction with cells expressing (GTL‐16 gastric carcinoma line) or not expressing (NIH‐3T3 fibroblasts) the Met/HGFR is analyzed. Functionalized nanoparticles specifically bind to and are internalized in cells expressing the receptor (GTL‐16) but not in the ones that do not express it (NIH‐3T3). Moreover they discharge DOXO in the targeted GTL‐16 cells that reach the nucleus and display cytotoxicity as assessed in an MTT assay. Two different types of ternary nanoparticles are prepared, differing for the sequence of the functionalization steps (adsorption of DOXO first and then mAb or vice versa), and it is found that the ones in which mAb is adsorbed first are more efficient under all the examined aspects (binding, internalization, cytotoxicity), possibly because of a better mAb orientation on the nanoparticle surface. These multifunctional nanoparticles could thus be useful instruments for targeted local or systemic drug delivery, allowing a reduction in the therapeutic dose of the drug and thus adverse side effects. Moreover, this work opens new perspectives in the use of nanocrystalline apatites as a new platform for theranostic applications in nanomedicine.
Droplet‐Based Microreactors for Continuous Production of Palladium Nanocrystals with Controlled Sizes and Shapes
Authors: Kim Yun Ho , Zhang Lei , Yu Taekyung , Jin Minshang , Qin Dong , Xia Younan
Published: April 2013

Droplet‐based microreactors are used for the continuous production of Pd nanocrystals. Specifically, commercially available polytetrafluoroethylene (PTFE) tube and silica capillaries are utilized to fabricate a fluidic device capable of generating water‐in‐oil droplets. In addition to the feasibility of using such droplets as microreactors for conducting a synthesis, the ability to control the composition and concentration of reagents by adjusting the flow rates is demonstrated; reagents are mixed by periodically pinching the PTFE tube, and nanocrystals are produced with uniform size distribution in a continuous fashion. The capability to tailor the size and shape of the resultant nanocrystals is further demonstrated by introducing the reducing agent and capping agent at different flow rates to control the nucleation and growth processes. The ability to transform a bulk synthesis into a droplet‐based system holds great potential for the development of a new route to the high‐volume production of nanocrystals.
Hydrothermal Growth of TiO2 Nanorod Arrays and In Situ Conversion to Nanotube Arrays for Highly Efficient Quantum Dot‐Sensitized Solar Cells
Authors: Huang Hui , Pan Lei , Lim Chiew Keat , Gong Hua , Guo Jun , Tse Man Siu , Tan Ooi Kiang
Published: April 2013

TiO2 nanorod (NR) and nanotube (NT) arrays grown on transparent conductive substrates are attractive electrode for solar cells. In this paper, TiO2 NR arrays are hydrothermally grown on FTO substrate, and are in situ converted into NT arrays by hydrothermally etching. The TiO2 NR arrays are reported as single crystalline, but the TiO2 NR arrays are demonstrated to be polycrystalline with a bundle of 2–5 nm single crystalline nanocolumns grown along [001] throughout the whole NR from bottom to top. TiO2 NRs can be converted to NTs by hydrothermal selective etching of the (001) core and remaining the inert sidewall of (110) face. A growth mechanism of the NR and NT arrays is proposed. Quantum dot‐sensitized solar cells (QDSCs) are fabricated by coating CdSe QDs on to the TiO2 arrays. After conversion from NRs to NTs, more QDs can be filled in the NTs and the energy conversion efficiency of the QDSCs almost double.
Microfluidic Surface‐Enhanced Raman Scattering Sensors Based on Nanopillar Forests Realized by an Oxygen‐Plasma‐Stripping‐of‐Photoresist Technique
Authors: Mao Haiyang , Wu Wengang , She Didi , Sun Gongchen , Lv Pengpeng , Xu Jun
Published: April 2013

A novel surface‐enhanced Raman scattering (SERS) sensor is developed for real‐time and highly repeatable detection of trace chemical and biological indicators. The sensor consists of a polydimethylsiloxane (PDMS) microchannel cap and a nanopillar forest‐based open SERS‐active substrate. The nanopillar forests are fabricated based on a new oxygen‐plasma‐stripping‐of‐photoresist technique. The enhancement factor (EF) of the SERS‐active substrate reaches 6.06 × 106, and the EF of the SERS sensor is about 4 times lower due to the influence of the PDMS cap. However, the sensor shows much higher measurement repeatability than the open substrate, and it reduces the sample preparation time from several hours to a few minutes, which makes the device more reliable and facile for trace chemical and biological analysis.
Photosystem I (PSI)/Photosystem II (PSII)‐Based Photo‐Bioelectrochemical Cells Revealing Directional Generation of Photocurrents
Authors: Yehezkeli Omer , Tel‐Vered Ran , Michaeli Dorit , Nechushtai Rachel , Willner Itamar
Published: April 2013

Layered assemblies of photosystem I, PSI, and/or photosystem II, PSII, on ITO electrodes are constructed using a layer‐by‐layer deposition process, where poly N,N′‐dibenzyl‐4,4′‐bipyridinium (poly‐benzyl viologen, PBV2+) is used as an inter‐protein “glue”. While the layered assembly of PSI generates an anodic photocurrent only in the presence of a sacrificial electron donor system, such as dichlorophenol indophenol (DCPIP)/ascorbate, the PSII‐modified electrode leads, upon irradiation, to the formation of an anodic photocurrent (while evolving oxygen), in the absence of any sacrificial component. The photocurrent is generated by transferring the electrons from the PSII units to the PBV2+ redox polymer. The charge‐separated species allow, then, the injection of the electrons to the electrode, with the concomitant evolution of O2. A layered assembly, consisting of a PSI layer attached to a layer of PSII by the redox polymer PBV2+, leads to an anodic photocurrent that is 2‐fold higher, as compared to the anodic photocurrent generated by a PSII‐modified electrode. This observation is attributed to an enhanced charge separation in the two‐photosystem assembly. By the further nano‐engineering of the two photosystems on the electrode using two different redox polymers, vectorial electron transfer to the electrode is demonstrated, resulting in a ca. 6‐fold enhancement in the photocurrent. The reversed bi‐layer assembly, consisting of a PSII layer linked to a layer of PSI by the PBV2+ redox polymer, yields, upon irradiation, an inefficient cathodic current. This observation is attributed to a mixture of photoinduced electron transfer reactions of opposing effects on the photocurrent directions in the two‐photosystem assembly.
Advanced Subcompartmentalized Microreactors: Polymer Hydrogel Carriers Encapsulating Polymer Capsules and Liposomes
Authors: Hosta‐Rigau Leticia , Shimoni Olga , Städler Brigitte , Caruso Frank
Published: April 2013

The design of compartmentalized carriers for advanced drug delivery systems or artificial cells and organelles is of interest for biomedical applications. Herein, a polymer carrier microreactor that contains two different classes of subcompartments, multilayered polymer capsules and liposomes, is presented. 50 nm‐diameter liposomes and 300 nm‐diameter polymer capsules are encapsulated into a larger polymer carrier capsule, demonstrating control over the spatial positioning of the subcompartments, which are either ‘membrane‐associated’ or 'free‐floating’ in the aqueous interior. Selective and spatially dependent degradation of the 300 nm‐diameter subcompartments (without destroying the structural integrity of the enzyme‐loaded liposomes) is also shown, by performing an encapsulated enzymatic reaction using the liposomal subcompartments. These findings cover several important aspects toward the development of engineered compartmentalized carrier vessels for the creation of artificial cell mimics or advanced therapeutic delivery systems.
Particle Formation in the Emulsion‐Solvent Evaporation Process
Authors: Staff Roland H. , Schaeffel David , Turshatov Andrey , Donadio Davide , Butt Hans‐Jürgen , Landfester Katharina , Koynov Kaloian , Crespy Daniel
Published: April 2013

The mechanism of particle formation from submicrometer emulsion droplets by solvent evaporation is revisited. A combination of dynamic light scattering, fluorescence resonance energy transfer, zeta potential measurements, and fluorescence cross‐correlation spectroscopy is used to analyze the colloids during the evaporation process. It is shown that a combination of different methods yields reliable and quantitative data for describing the fate of the droplets during the process. The results indicate that coalescence plays a minor role during the process; the relatively large size distribution of the obtained polymer colloids can be explained by the droplet distribution after their formation.
Operations Research (OR) in Service Industries: A Comprehensive Review
Authors: Xing Yiting , Li Ling , Bi Zhuming , Wilamowska‐Korsak Marzena , Zhang Li
Published: April 2013

The share of gross domestic product from the service industry reflects the competitiveness of a nation; the service industry in the USA accounts for around 80% of its gross domestic product, and it has been increasing gradually. Continual innovations and advances in enabling technologies for the service industry are crucial for developed countries to sustain their leading positions in the globalized economy. To clarify future research directions of operations research (OR) in the service industry, the state of art of OR has been examined systematically, the new requirements of OR are identified for its applications in service industries in comparison with those in manufacturing industries, and the limitations of existing methodologies and tools have been discussed. This paper was intended to provide an updated review on how OR has been applied in the service sector in recent years and what directions the study of OR will be carried forward in the near future. Under a proposed research framework, recent OR‐related articles were collected from 17 leading OR journals and classified into the five most active sectors, that is, transportation and warehousing, information and communication, human health and social assistance, retails and wholesales, and financial and insurance services. The conclusions on the limitations of existing studies and the demanding ORs in the service have been drawn from our summaries and observations from a comprehensive review in this field. Copyright © 2013 John Wiley & Sons, Ltd.
Knowledge representation and processing with formal concept analysis
Authors: Kuznetsov Sergei O. , Poelmans Jonas
Published: April 2013

During the last three decades, formal concept analysis (FCA) became a well‐known formalism in data analysis and knowledge discovery because of its usefulness in important domains of knowledge discovery in databases (KDD) such as ontology engineering, association rule mining, machine learning, as well as relation to other established theories for representing knowledge processing, like description logics, conceptual graphs, and rough sets. In early days, FCA was sometimes misconceived as a static crisp hardly scalable formalism for binary data tables. In this paper, we will try to show that FCA actually provides support for processing large dynamical complex (may be uncertain) data augmented with additional knowledge. © 2013 Wiley Periodicals, Inc.

This article is categorized under:

Fundamental Concepts of Data and Knowledge > Key Design Issues in Data Mining

Fundamental Concepts of Data and Knowledge > Knowledge Representation

Technologies > Computational Intelligence
RNA synthetic mechanisms employed by diverse families of RNA viruses
Authors: McDonald Sarah M.
Published: April 2013

RNA viruses are ubiquitous in nature, infecting every known organism on the planet. These viruses can also be notorious human pathogens with significant medical and economic burdens. Central to the lifecycle of an RNA virus is the synthesis of new RNA molecules, a process that is mediated by specialized virally encoded enzymes called RNA‐dependent RNA polymerases (RdRps). RdRps directly catalyze phosphodiester bond formation between nucleoside triphosphates in an RNA‐templated manner. These enzymes are strikingly conserved in their structural and functional features, even among diverse RNA viruses belonging to different families. During host cell infection, the activities of viral RdRps are often regulated by viral cofactor proteins. Cofactors can modulate the type and timing of RNA synthesis by directly engaging the RdRp and/or by indirectly affecting its capacity to recognize template RNA. High‐resolution structures of RdRps as apoenzymes, bound to RNA templates, in the midst of catalysis, and/or interacting with regulatory cofactor proteins, have dramatically increased our understanding of viral RNA synthetic mechanisms. Combined with elegant biochemical studies, such structures are providing a scientific platform for the rational design of antiviral agents aimed at preventing and treating RNA virus‐induced diseases. WIREs RNA 2013, 4:351–367. doi: 10.1002/wrna.1164

This article is categorized under:

RNA Interactions with Proteins and Other Molecules > RNA–Protein Complexes

RNA in Disease and Development > RNA in Disease
The Periodate‐Based Double Perovskites M2NaIO6 (M = Ca, Sr, and Ba)
Authors: Kubel Frank , Wandl Nicole , Pantazi Mariana , D'Anna Vincenza , Hagemann Hans
Published: April 2013

The crystal structures of the M2NaIO6 series (M = Ca, Sr, Ba), prepared at 650 °C by ceramic methods, were determined from conventional laboratory X‐ray powder diffraction data. Synthesis and crystal growth were made by oxidizing I– with O2(air) to I7+ followed by crystal growth in the presence of NaF as mineralizator, or by the reaction of the alkali‐metal periodate with the alkaline‐earth metal hydroxide. All three compounds are insoluble and stable in water. The barium compound crystallizes in the cubic space group Fm3m (no. 225) with lattice parameters of a = 8.3384(1) Å, whereas the strontium and calcium compounds crystallize in the monoclinic space group P21/c (no. 14) with a = 5.7600(1) Å, b = 5.7759(1) Å, c = 9.9742(1) Å, β = 125.362(1)° and a = 5.5376(1) Å, b = 5.7911(1) Å, c = 9.6055(1) Å, β = 124.300(1)°, respectively. The crystal structure consists of either symmetric (for Ba) or distorted (for Sr and Ca) perovskite superstructures. Ba2NaIO6 contains the first perfectly octahedral [IO6]5– unit reported. The compounds of the ortho‐periodates are stable up to 800 °C. Spectroscopic measurements as well as DFT calculations show a reasonable agreement between calculated and observed IR‐ and Raman‐active vibrations.
Differences Between Attendings’ and Residents’ Operative Notes for Laparoscopic Cholecystectomy
Authors: Wauben Linda S. G. L. , Goossens Richard H. M. , Lange Johan F.
Published: April 2013

Background

Operative notes are the gold standard for detecting adverse events and near misses and form the basis for scientific research. In order to guarantee safe patient care, operative notes must be objective, complete, and accurate. This study explores the current routine of note writing for laparoscopic cholecystectomy (LC) and the differences between the notes of attendings and residents.

Methods

Attendings and residents were sent a DVD with footage of three LCs and were asked to “write” the corresponding notes and to complete a questionnaire. Dictation tapes were transcribed and items in the notes were analyzed for each procedure (“item described” or “item not described”). Fisher’s exact tests were performed using SPSS 16.0 for Mac.

Results

Thirteen sets of typewritten notes and 10 dictation tapes were returned. The results of the questionnaire showed that 16 of the 23 sets of notes were dictated. Eight participants found the current system for generating notes inadequate. 14 items (31 %) were included more often in the attendings’ notes and 25 items (56 %) were included more often in the residents’ notes. Overall, residents significantly more often described the location of the epigastric trocar (P = 0.018), the size of both working trocars (P = 0.019), the opening of the peritoneal envelope (P = 0.002), Critical View of Safety reached (P = 0.002), and the location for removing the gallbladder (P = 0.019). With the exception of “gallbladder perforation” (20 of 21 notes), complications were underreported.

Conclusions

In this study residents described more items than attendings. All notes lacked information concerning complications in the procedure, which makes the notes subjective and incomplete. A procedure‐specific template or black‐box‐based operative notes based on established guidelines could improve the quality of the notes of both attendings and residents.
Clinical importance of Familial Pancreatic Cancer Registry in Japan: a report from kick‐off meeting at International Symposium on Pancreas Cancer 2012
Authors: Wada Keita , Takaori Kyoichi , Traverso L. William , Hruban Ralph H. , Furukawa Toru , Brentnall Teresa A. , Hatori Takashi , Sano Keiji , Takada Tadahiro , Majima Yoshiyuki , Shimosegawa Tooru
Published: April 2013

Pancreatic cancer is still a highly lethal disease with a 5‐year survival rate of approximately 5 %. Early detection offers one of the best hopes for improving survival. Previous cohort studies and case—control studies showed that 4—10 % of pancreatic cancers have a hereditary basis, and individuals with a family history have an increased risk of developing pancreatic and extra‐pancreatic malignancies. Since individuals with a family history of pancreatic cancer and those with a known genetic syndrome that predisposes to pancreatic cancer will be the first to benefit from early detection tests as they become available, familial pancreatic cancer (FPC) registries have been established in the US and Europe, but not yet in Japan. Such registries form the basis for epidemiological studies, clinical trials, and basic research on familial pancreatic cancer. There is a need for FPC registries in Japan as cancer risk varies among different populations and discoveries made in Western populations may not translate to the Japanese population. These registries in Japan will align with ongoing international efforts and add to a better understanding of the natural history, risk factors, screening strategies, and responsible genes, for improving survival of this dismal disease.
Influence of 1,3‐Butanediol on the Viscoelasticity of Surfactant Solutions
Authors: Abdel‐Rahem Rami A.
Published: April 2013

The rheological behavior of rodlike micelles in a 1,3‐butanediol/water mixed solvent was investigated. The rodlike micelles were prepared by mixing sodium salicylate, with cetyltrimethylammonium bromide. When water was replaced by 1,3‐butanediol, the viscosity maxima decreased drastically. The viscosity minimum, on the other hand, increased at low 1,3‐butanediol contents and decreased again at higher amounts of 1,3‐butanediol. As a result of the opposite changes the two maxima were replaced by a single maxima when the content of 1,3‐butanediol was 15 %. The change in the viscosity was a consequence of a change in the structural relaxation times while the storage moduli remained constant. The stress relaxation was due to a reptation mechanism at maximum points while at the minimum of the viscosity the mechanism was due to a kinetic controlled mechanism.
Characteristics of Oil and Skim in Enzyme‐Assisted Aqueous Extraction of Soybeans
Authors: de Moura Bell J. M. L. N. , Maurer D. , Yao L. , Wang T. , Jung S. , Johnson L. A.
Published: April 2013

The economic viability of enzyme‐assisted aqueous extraction processing (EAEP) of soybeans depends on properties and potential applications of all fractions (skim and insolubles as well as oil). EAEP oil contained lower free fatty acid, phosphorus, and tocopherol contents, similar unsaponifiable matter levels, and higher degrees of oxidation (peroxide and p‐anisidine values) than hexane‐extracted oil. The phospholipid profile of EAEP fractions was mainly composed of phosphatidic acid, followed by phosphatidylcholine, phosphatidylinositol, and phosphatidylethanolamine. Most of phospholipids were present in the skim, except for phosphatidic acid, which was the major phospholipid in the cream fraction. Skim and cream contained 55 and 3 % of the soluble carbohydrates in the original extruded flakes, respectively. Soluble carbohydrates of the skim were mainly composed of stachyose (5.8 ± 0.8 mg/mL) and sucrose (9.9 ± 0.8 mg/mL), which were hydrolyzed into glucose, galactose, and fructose after addition of α‐galactosidase. Skim and cream peptides contained <20 kDa MW molecules. About 71 % of the skim peptides were <20 kDa MW, with 49 % being <1.35 kDa MW, 22 % being 17–1.35 kDa MW, and 29 % being 44–670 kDa MW. Skim protein and carbohydrate contents make this fraction suitable for replacing water in ethanol fermentations, thereby improving the fermentation rate/production and the nutritional quality of distiller's dried grains with solubles.
Turkmenistan and Military Buildup in the Caspian Region: A Small State in the Post-Unipolar Era
Authors: Shlapentokh Dmitry
Published: April 2013

Caspian Sea had been actually a Soviet internal lake. Iran was too weak to be a competitor/rival for the USSR. The collapse of the USSR had transformed Caspian Sea into the sea surrounded by several states and each of them vie for the Caspian Sea's natural resources. Caspian Sea became also important as the route for delivery of oil/gas. All of this led to considerable tensions among the states in the area and naval buildup. Even Turkmenistan, desert republic, started to build the navy and contribute to the rise of tension in Caspian Sea. All of this indicated the increasing global instability which followed the end of Cold War and the end of the USA unipolarity.
An Analytical Study of Geopolitical Consequences of Normalization of Turkish–Armenian Relations
Authors: Valigholizadeh Ali , Zaki Yashar , Barani Kazem Zoghi
Published: April 2013

In order to study the Turkey–Armenia relations in past and present times and their processes, the current paper, taking into account geopolitical views, tries to analyze the political and economic consequences of normalization of Turkey–Armenia relationships. With respect to the outcome of this research, it seems, expansion of such ties would benefit Ankara, only if the national interests of other regional states are taken into account. In other words, ignoring the interests of other regional states in the course of normalization of Turkey–Armenia relations would damage the Turkish interests and its relations with Azerbaijan and Georgia. From the point of views of influential regional powers, too, the possible consequences of expansion of Turkey–Armenia ties would accompany particular complexities. With the expansion of such ties, we may see a kind of balance of influence between profit seeking powers in the region.
EFA6 activates Arf6 and participates in its targeting to the Flemming body during cytokinesis
Authors: Ueda Tomoko , Hanai Ayako , Takei Tomomi , Kubo Keiji , Ohgi Minako , Sakagami Hiroyuki , Takahashi Senye , Shin Hye-Won , Nakayama Kazuhisa
Published: April 2013

The small GTPase Arf6 is transiently associated with the ingressing cleavage furrow and subsequently targeted to the Flemming body during cytokinesis, suggesting its activation around the cleavage furrow. Here, we show that EFA6 (exchange factor for Arf6) localizes on the cleavage furrow through its PH domain. Time‐lapse analysis showed that both EFA6 and Arf6 are transiently localized around the ingressing cleavage furrow, but only Arf6 is subsequently targeted to the Flemming body. Expression of an EFA6 mutant suppresses Arf6 recruitment onto the Flemming body. These results suggest that EFA6 participates in activation of Arf6 around the cleavage furrow during cytokinesis.
Stochastic machines as a colocalization mechanism for scaffold protein function
Authors: Xue Bin , Romero Pedro R. , Noutsou Maria , Maurice Madelon M. , Rüdiger Stefan G.D. , William Albert M. , Mizianty Marcin J. , Kurgan Lukasz , Uversky Vladimir N. , Dunker A. Keith
Published: April 2013

The axis inhibition (Axin) scaffold protein colocalizes β‐catenin, casein kinase Iα, and glycogen synthetase kinase 3β by their binding to Axin's long intrinsically disordered region, thereby yielding structured domains with flexible linkers. This complex leads to the phosphorylation of β‐catenin, marking it for destruction. Fusing proteins with flexible linkers vastly accelerates chemical interactions between them by their colocalization. Here we propose that the complex works by random movements of a “stochastic machine,” not by coordinated conformational changes. This non‐covalent, modular assembly process allows the various molecular machine components to be used in multiple processes.
Structural determinants for phosphatidylinositol recognition by Sfh3 and substrate‐induced dimer–monomer transition during lipid transfer cycles
Authors: Yang Huiseon , Tong Junsen , Leonard Thomas A. , Im Young Jun
Published: April 2013

Sec14 family homologs are the major yeast phosphatidylinositol/phosphatidylcholine transfer proteins regulating lipid metabolism and vesicle trafficking. The structure of Saccharomyces cerevisiae Sfh3 displays a conserved Sec14 scaffold and reveals determinants for the specific recognition of phosphatidylinositol ligand. Apo‐Sfh3 forms a dimer through the hydrophobic interaction of gating helices. Binding of phosphatidylinositol leads to dissociation of the dimer into monomers in a reversible manner. This study suggests that the substrate induced dimer–monomer transformation is an essential part of lipid transfer cycles by Sfh3.
Klotho sensitivity of the hERG channel
Authors: Munoz Carlos , Pakladok Tatsiana , Almilaji Ahmad , Elvira Bernat , Seebohm Guiscard , Voelkl Jakob , Föller Michael , Shumilina Ekaterina , Lang Florian
Published: April 2013

Klotho, a hormone and enzyme, is a powerful regulator of ageing and life span. Klotho deficiency leads to cardiac arrythmia and sudden cardiac death. We thus explored whether klotho modifies cardiac K+‐channel hERG. Current was determined utilizing dual electrode voltage clamp and hERG protein abundance utilizing immunohistochemistry and chemiluminescence in Xenopus oocytes expressing hERG with or without klotho. Coexpression of klotho increased cell membrane hERG‐protein abundance and hERG current at any given voltage without significantly modifying the voltage required to activate the channel. The effect of klotho coexpression was mimicked by recombinant klotho protein and reversed by β‐glucuronidase‐inhibitor d‐saccharic acid‐1,4‐lactone.