bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of BZSM‐5 Membranes Using Nano‐Zeolitic Seeds: Characterization and Separation Performance
Authors: Saboor F. H. , Ashrafizadeh S. N. , Kazemian H.
Published: March 2012

Nanoseeds of BZSM‐5 zeolite with a narrow particle size distribution of 100–200 nm were successfully prepared under mild hydrothermal conditions. Thin and oriented BZSM‐5 membranes of 3–4 μm, prepared at low temperature, were manufactured and examined for the separation of 5 wt‐% ethanol/water mixtures. Separation factor and flux were 13.93 and 1.11 kg m–2h–1, respectively. The temperature of synthesis showed a remarkable influence on the morphology, crystal orientation and separation performance of the membranes. The thinner a,b‐oriented membrane showed a higher separation performance than the thicker h0h‐oriented one.
Improvement of the Uniformity of Radial Solids Concentration Profiles in Circulating Fluidized‐Bed Risers
Authors: Peng B. , Zhang C. , Zhu J.
Published: March 2012

In order to enhance the uniformity of the radial solids distribution and thereby the performance of industrial circulating fluidized‐bed (CFB) risers, an approach by using the air jet from the riser circumference is proposed. The Eulerian‐Eulerian computational fluid dynamics (CFD) model with the kinetic theory of granular flow is adopted to simulate the gas‐solids two‐phase flow in a CFB riser with fluid catalytic cracking (FCC) particles. The numerical results indicate that by employing the circumferential air jet approach under appropriate jet velocities, the maximum solids concentration in the near‐wall region can be greatly reduced, the entrance region can be shortened, and the uniformity of the flow structure can be significantly improved.
Trickle flow liquid–solid mass transfer and wetting efficiency in small diameter columns
Authors: Joubert Rita , Nicol Willie
Published: March 2012

A novel method to simultaneously measure liquid solid mass transfer and external wetting efficiency was employed at column to particle ratios of 10, 6 and 3. Two prewetting procedures representing the upper (Kan) and lower (Levec) hysteresis branches were used. For a multipoint distributor on a Kan prewetted bed wetting efficiency and the specific mass transfer coefficient were almost unaffected by column diameter. The multipoint distributor on a Levec prewetted bed exhibited a decrease in specific mass transfer with decreasing column diameter. Point source experiments resulted in significantly lower wetting and mass transfer measurements with an increasing trend with respect to decreasing column diameter. The results indicate that with proper distribution and prewetting, the effect of column diameter on averaged wetting and liquid–solid mass transfer is almost negligible, a powerful result considering the importance of these parameters on reaction experiments. © 2012 Canadian Society for Chemical Engineering
Cofilin is required for organization of sarcomeric actin filaments in chicken skeletal muscle cells
Authors: Miyauchi‐Nomura Saeko , Obinata Takashi , Sato Naruki
Published: March 2012

Cofilin is an actin regulatory protein that plays a critical role in actin filament dynamics in a variety of cells. We have previously demonstrated that excess cofilin in skeletal muscle cells leads to disruption of actin filaments, followed by actin‐cofilin rod formation in the cytoplasm. In this study, to further clarify the role of cofilin in actin assembly during myofibrillogenesis, cofilin expression was suppressed in cultured chicken skeletal muscle cells. First, we confirmed that turnover of cofilin in myotubes was much higher than that of actin, and that the cofilin level could be decreased drastically within 2 days when cofilin de novo synthesis was suppressed. Next, cofilin expression in individual myotubes was suppressed by introducing antisense morpholino oligonucleotides into the cells by microinjection. Cofilin depletion at the early phase of myofibrillogenesis caused abnormal actin aggregates in myotubes and impaired actin organization into cross‐striated myofibril structures. However, when cofilin expression was suppressed in developed myotubes, actin localization in striated myofibrils was scarcely affected. These results indicate that cofilin plays a critical role in the regulation of actin assembly at the early process of myofibrillogenesis. © 2012 Wiley Periodicals, Inc
Optimizing network performance and carbon offset through opportunistic reclustering
Authors: Habib Sami J. , Marimuthu Paulvanna N.
Published: March 2012

We have viewed an enterprise information network as a flexible topology, where each node seeks the opportunity to join a cluster having high association with its nodes to reduce the external bandwidth and thereby producing less carbon. The opportunistic clustering is modeled as an optimization problem and we utilized heuristics such as genetic algorithm (GA) and simulated annealing (SA) to search for the best opportunistic topology. We have proposed redesign operations such as move and swap nodes to change the existing topology into an opportunistic topology. Also, we defined an opportunistic factor ranging from +1 to –1 to measure the gain in bandwidth and the amount of reduction in carbon emissions. Our simulation results demonstrate positive opportunistic factor in individual clusters from 0.4 to 0.7 in move operation, thereby showing a total bandwidth gain of 21% and 19% within GA and SA, respectively. In the swap operation, the opportunistic factor reached a maximum of 0.3, thereby showing a bandwidth gain of 9.7% and 5.1% within GA and SA, respectively. It is also observed that the optimization within GA outperforms SA in offsetting carbon emission with a maximum of 22%. Copyright © 2012 John Wiley & Sons, Ltd.
Atomic Layer Deposition‐Modified Ordered Mesoporous Silica Membranes
Authors: Cassidy David E. , DeSisto William J.
Published: March 2012

Mesoporous silica membranes, prepared by surfactant‐templating with a pore diameter of ∼4 nm on an alumina support, are modified by atomic layer deposition (ALD) of aluminum oxide. ALD of aluminum oxide is achieved using trimethyl aluminum (TMA) and water as reactants. Membranes modified up to 50 ALD reaction cycles are characterized periodically during progressive reaction cycles to provide details of the pore modification process. A decrease in light gas permeance, pore size distribution shift to lower pore sizes, and a decrease in porosity provide evidence for pore‐size reduction through ALD. Further analysis of the data indicates that the ALD reaction favors larger pores and defects, and becomes less efficient as the pore size decreases.
Modeling Fluid Flow in the Gas Diffusion Layers in PEMFC Using the Multiple Relaxation‐time Lattice Boltzmann Method
Authors: Gao Y. , Zhang X. X. , Rama P. , Liu Y. , Chen R. , Ostadi H. , Jiang K.
Published: March 2012

The gas diffusion layers (GDLs) are key components in proton exchange membrane fuel cells and understanding fluid flow through them plays a significant role in improving fuel cell performance. In this paper we used a combination of multiple‐relaxation time lattice Boltzmann method and imaging technology to simulate fluid flow through the void space in a carbon paper GDL. The micro‐structures of the GDL were obtained by digitizing 3D images acquired by X‐ray computed micro‐tomography at a resolution of 1.76 μm, and fluid flow through the structures was simulated by applying pressure gradient in both through‐plane and in‐plane directions, respectively. The simulated velocity field at micron scale was then used to estimate the anisotropic permeability of the GDL. To test the method, we simulated fluid flow in a column packed with glass beads and the estimated permeability was found to be in good agreement with experimental measurements. The simulated results for the GDL revealed that the increase of permeability with porosity was well fitted by the model of Tomadakis–Sotirchos [48] without fitting parameters. The permeability calculated using fluids with different viscosities indicated that the multiple‐relaxation time lattice Boltzmann method provides robust solutions, giving a viscosity‐independent permeability. This is a significant improvement over the commonly used single‐time relaxation lattice Boltzmann model which was found to give rise to a unrealistic viscosity‐dependent permeability because of its inaccuracy in solving the fluid–solid boundaries.
Experimental Investigation of Air Relative Humidity (RH) Cycling Tests on MEA/Cell Aging in PEMFC Part I: Study of High RH Cycling Test With air RH at 62%/100%
Authors: Huang B. T. , Chatillon Y. , Bonnet C. , Lapicque F. , Leclerc S. , Hinaje M. , Raël S.
Published: March 2012

The effect of high air relative humidity (RH) cycling (RHC 62%/100%) on the degradation mechanisms of a single (5 × 5 cm2) proton exchange membrane fuel cells was investigated. The cell performance was compared to a cell operated at constant humidification (RHC = 62%). Runs were conducted over approximately 1,500 h at 0.3 A cm–2. The overall loss in cell performance for the high RH cycling test was 12 μV h–1 whereas it was at 3 μV h–1 under constant humidification. Impedance spectroscopy reveals that the ohmic and charge transfer resistances were little modified in both runs. H2 crossover measurement indicated that both high RH cycling and constant RH test did not promote serious effect on gas permeability. The electroactive surface loss for anode and cathode during high air RH cycling was more significant than at constant RH operation. The water uptake determined by 1H nuclear magnetic resonance within the membrane electrode assembly (MEA) after high RH cycling was reduced by 12% in comparison with a fresh MEA. Transmission electron microscopy showed bubbles and pinholes formation in the membrane, catalyst particles agglomeration (also observed by X‐ray diffraction), catalyst particles migration in the membrane and thickness reduction of the catalytic layers. Scanning electron microscopy was conducted to observe the changes in morphology of gas diffusion layers after the runs.
Evaluation of the Performance of Platinum Nanoparticle–Titanium Oxide Nanotubes as a New Refreshable Electrode for Formic Acid Electro‐oxidation
Authors: Hosseini M. G. , Momeni M. M.
Published: March 2012

Platinum nanoparticles (Pt‐NP) are deposited on the surface of titanium oxide nanotubes (TN) by microemulsion method. Highly ordered TN on a pure titanium substrate are successfully fabricated by anodizing of titanium. The morphology and surface analysis of Pt‐NP/TN electrodes were investigated using scanning electron microscopy and X‐ray diffraction spectroscopy, respectively. The electro‐oxidation of formic acid on Pt‐NP/TN electrodes in acidic medium was studied by cyclic voltammetry and chronoamperometry methods. The results showed that the oxidation peak currents on the Pt‐NP/TN electrode for formic acid oxidation are several times larger than a smooth platinum electrode and confirmed the better electro‐catalytic activity and stability of these new electrodes. The photocatalytic properties of titanium oxide make the Pt‐NP/TN electrode reusable after a short UV treatment, and the electro‐oxidation current density of Pt‐NP/TN electrode after UV‐cleaning can be re‐established. So Pt‐NP/TN electrode has a good application potential to fuel cells.
Assessing the potential of reservoir outflow management to reduce sedimentation using continuous turbidity monitoring and reservoir modelling
Authors: Lee Casey , Foster Guy
Published: March 2012

In‐stream sensors are increasingly deployed as part of ambient water quality‐monitoring networks. Temporally dense data from these networks can be used to better understand the transport of constituents through streams, lakes or reservoirs. Data from existing, continuously recording in‐stream flow and water quality monitoring stations were coupled with the two‐dimensional hydrodynamic CE‐QUAL‐W2 model to assess the potential of altered reservoir outflow management to reduce sediment trapping in John Redmond Reservoir, located in east‐central Kansas. Monitoring stations upstream and downstream from the reservoir were used to estimate 5.6 million metric tons of sediment transported to John Redmond Reservoir from 2007 through 2010, 88% of which was trapped within the reservoir. The two‐dimensional model was used to estimate the residence time of 55 equal‐volume releases from the reservoir; sediment trapping for these releases varied from 48% to 97%. Smaller trapping efficiencies were observed when the reservoir was maintained near the normal operating capacity (relative to higher flood pool levels) and when average residence times were relatively short. An idealized, alternative outflow management scenario was constructed, which minimized reservoir elevations and the length of time water was in the reservoir, while continuing to meet downstream flood control end points identified in the reservoir water control manual. The alternative scenario is projected to reduce sediment trapping in the reservoir by approximately 3%, preventing approximately 45 000 metric tons of sediment from being deposited within the reservoir annually. This article presents an approach to quantify the potential of reservoir management using existing in‐stream data; actual management decisions need to consider the effects on other reservoir benefits, such as downstream flood control and aquatic life. Copyright © 2012 John Wiley & Sons, Ltd.
Etiology of preschool behavior problems: Contributions of temperament attributes in early childhood
Authors: Gartstein Maria A. , Putnam Samuel P. , Rothbart Mary K.
Published: March 2012

The present study was conducted to examine the contributions of early appearing temperament attributes to toddler and preschool‐age behavior problems. High levels of negative emotionality and low levels of effortful control were linked to both externalizing and internalizing difficulties. All fine‐grained dimensions of negative affect were concurrently associated with internalizing problems whereas relations between components of negative affect and externalizing were observed only for frustration, sadness, and low falling reactivity. Higher surgency was associated with increased risk for externalizing behaviors whereas low surgency increased the likelihood of internalizing problems. Trait‐by‐trait moderation occurred, such that negative emotionality was most closely related to behavior problems when orienting/regulatory capacity or effortful control was low or when infant surgency was high. Results of this study have implications for theory linking temperament and psychopathology, and clinical applications utilizing temperament assessment to prevent behavior problems.
INTEGRATED METAHEURISTIC OPTIMIZATION OF 130–30 INVESTMENT‐STRATEGY‐BASED LONG–SHORT PORTFOLIOS
Authors: Vijayalakshmi Pai G.A. , Michel Thierry
Published: March 2012

A 130–30 strategy is an attractive and viable equity investment strategy for building long–short portfolios and notionally expected to enhance investment exposure and market protection. However, the amalgamation of the strategy in the portfolio optimization problem model poses complex constraints which render the problem model difficult for solving using traditional methods, thus justifying the application of metaheuristic solutions.

We discuss a metaheuristic and integrated optimization of long–short portfolios, when the 130–30‐strategy‐based constraint, besides other investor preferential constraints, is incorporated in the problem's formulation. In the absence of reported work and for reasons of performance comparison and analysis, two metaheuristic strategies have been proposed in order to solve the problem: (i) evolution strategy with hall of fame and (ii) differential evolution (rand/1/bin) with hall of fame. The experimental studies were undertaken on the Bombay Stock Exchange (BSE200) and Tokyo Stock Exchange (Nikkei 225) data sets and specifically for the period March 1999–March 2009, which included both upturns and downturns in the global markets. The efficiencies of the portfolios obtained by the two metaheuristic methods were analysed using an efficiency improvement possibility function, a portfolio productivity indicator which is a variation of Luenberger's shortage functions. Copyright © 2012 John Wiley & Sons, Ltd.
‘I am absolutely shattered’: The impact of chronic low back pain on Australian Aboriginal people
Authors: Lin I.B. , O'Sullivan P.B. , Coffin J.A. , Mak D.B. , Toussaint S. , Straker L.M.
Published: March 2012

Background

Aboriginal people in Australia have been uniquely identified as less susceptible to chronic low back pain (CLBP) disability when compared to non‐Aboriginal populations, reportedly due to cultural beliefs about pain. A qualitative, culturally secure research approach was used to explore this assumption.

Methods

In‐depth interviews were undertaken with 32 Aboriginal men and women with CLBP in regional and remote areas of Western Australia. Interviews were conducted collaboratively with male and female Aboriginal co‐investigators, and with the support of local Aboriginal community organizations. A primary focus was to investigate the impact of CLBP from the perspective of Aboriginal people living with the condition.

Results

The experience of CLBP was found to be multidimensional, impacting on activities of daily life, employment, sport and family participation, emotional and cultural well‐being.

Conclusions

Contrary to previous assumptions, CLBP is profoundly disabling for some Aboriginal people and a priority health concern. Issues of gender, cultural obligations and the emotional consequences of CLBP are important consideration for health care. These findings, and the contextual approach used to gain an in‐depth understanding of CLBP, may be relevant to populations elsewhere.
Effects of dexmedetomidine on conditioned pain modulation in humans
Authors: Baba Y. , Kohase H. , Oono Y. , Fujii‐Abe K. , Arendt‐Nielsen L.
Published: March 2012

Background

Systemic administration of dexmedetomidine (DEX; selective α2‐adrenoceptor agonist) is found to inhibit diffuse noxious inhibitory control in rats, now referred to as conditioned pain modulation (CPM) in humans. The present study was designed to investigate the effect of intravenous administration of DEX on CPM in humans.

Methods

There were two sequential sessions in this double blind, randomized study. The first session was the control with normal saline infusion (N1st, L1st, H1st). During the second session, three types of agents were infused: normal saline (N2nd); a low plasma concentration of DEX (0.04 ng/mL; L2nd); and a high plasma concentration of DEX (0.08 ng/mL; H2nd).

The amplitude of somatosensory evoked potentials (ampSEP)s and the visual analogue scale of tooth pain (VASt) induced by electrical tooth stimulation were evaluated with and without conditioning CO2 laser stimulation of the hand. The inhibition rate (% inhibition) was calculated [= (1‐[ampSEP or VASt with conditioning stimuli]/[ampSEP or VASt without conditioning stimuli]) × 100] to compare the magnitude of the DEX effects on CPM.

Results

The inhibition rates of ampSEPs and VASt in Types N, L and H varied significantly, demonstrating a dose‐dependent reduction of CPM effects of ampSEP and VASt during randomized DEX administration, consistent with results from animal studies.

Conclusions

The present study shows that systemic administration of an α2‐adrenoceptor agonist (DEX), less than the clinical dose, inhibited CPM in humans. These results may provide some mechanistic insight into why many chronic pain patients show impaired CPM.
Reclaiming Literacy Classrooms Through Critical Dialogue
Authors: Fecho Bob , Coombs Dawan , McAuley Sean
Published: March 2012

Authors Fecho, Coombs, and McAuley discuss the integral role of dialogue in literacy classrooms dominated by standardized testing, curriculum, and instruction. Their argument in support of the dialogical literacy classroom begins with a historical and theoretical justification for these principles, then transitions into a discussion of the troubling condition of schools as a result of the current lack of dialogue. By including the voices of students and teachers, the authors offer glimpses into classrooms in need of dialogical transactions. This commentary concludes with a call to teachers, policy makers, and community members to consider what educators risk when they fail to open up classrooms as places where diverse perspectives can be heard and individual meaning can be made of the texts of students’ lives. In addition, the authors argue here that establishing a critical dialogue in literacy classrooms is needed, perhaps now more than at any time in our past.
“Without Comic Books, There Would Be No Me”: Teachers as Connoisseurs of Adolescents’ Literate Lives
Authors: Simon Rob
Published: March 2012

This article explores the notion of connoisseurship as a framework for learning about adolescents’ lives and literacies and developing relationships in literacy classrooms. Drawing upon data from a two‐year qualitative study of the collaborative inquiries of a community of student English teachers, the author examines inquiry projects written for an English methods course in which two student teachers, Alex and Jared, construct counternarratives about the promise of students who had been positioned as problems within their schools. These examples illustrate how becoming connoisseurs of adolescents’ distinctiveness and abilities can be a basis for developing counterpractices in literacy classrooms, opening spaces of possibility for otherwise struggling students to begin to reorient their negative trajectories in school. Among other implications, this work suggests the positive consequences of teachers’ attentiveness to students’ literacy practices, and the importance of teachers cultivating more relational stances toward students.
The Power of the Sketch(Book): Reflections From High School English Students
Authors: Rebecca Leigh S.
Published: March 2012

This paper explores the potential of sketchbooks as a pathway for developing ideas for writing in high school English classrooms. This paper examines how shifting between drawing and writing impacts students’ ability to develop ideas for writing and create meaningful texts. Specifically, this paper explores four types of visual sign making that students use in mediating, expressing, and representing meaning. Findings in this study suggest that sketchbooks can be used as an effective tool for inquiry in the pedagogy of writing instruction. As well, students’ voices offer clarification on perceptions about art and language as modes of expression which suggest curricular changes for the secondary English classroom.
Books for Adolescents
Authors: Blasingame James , Fruth Nicole , Sahlin Jacqueline , Votaw Marsha , Cummins Sunday , Masser Carol , Turchi Laura
Published: March 2012

This department offers reviews of new YA titles.
Classroom Materials
Authors: Hryniuk‐Adamov Carol
Published: March 2012

This department offers an in‐depth review of classroom resources.
The political economy of financial reform: How robust are huang's findings?
Authors: Zandberg Eelco , Haan Jakob De , Paul Elhorst J.
Published: March 2012

Using new data on financial liberalization taken from Abiad et al. (2008, IMF Working Papers, No. 08/266) for 62 countries over the period 1975–2005, we show that some of the main findings of Huang's (2009, Journal of Applied Econometrics 24: 1207–1213) replication study on the drivers of financial liberalization are not robust. Major changes concern the effect of democracy on financial reform and the supposed relationship between the desired level of financial liberalization and a country's per capita income. Copyright © 2012 John Wiley & Sons, Ltd.
The impact of immobilization of BMP‐2 on PDO membrane for bone regeneration
Authors: Kim Ji‐Eun , Lee Eun‐Jung , Kim Hyoun‐Ee , Koh Young‐Hag , Jang Jun‐Hyeog
Published: March 2012

Poly(dioxanone) (PDO) is colorless, crystalline, a biodegradable synthetic polymers that is used for biomedical applications, such as surgical sutures, cardiovascular applications, orthopedics, and plastic surgery. Recently, bone morphogenetic protein‐2 (BMP‐2) is widely used for bone tissue engineering. For the first time we report here on the in vitro performance of an electrospun PDO membrane immobilized with BMP‐2. Immobilized BMP‐2 on PDO membrane enhanced ALPase activity, the osteogenic differentiation gene expressions as well as cell attachment, except cell proliferation when compared to that of PDO membrane alone. These results suggest that PDO membrane with BMP‐2 is helpful to promote bone healing and regeneration. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2012.
Chemical reactivity in the framework of pair density functional theories
Authors: Otero Nicolás , Mandado Marcos
Published: March 2012

Chemical reactivity descriptors are derived within the framework of the pair density functional theory. These indices provide valuable information about bonding rearrangements and activating mechanisms upon electrophilic or nucleophilic reactions. Indices derived and tested in this work represent nonlocal counterparts of the local reactivity indices derived in the context of conceptual density functional theory (CDFT) and frequently used in reactivity studies; the Fukui function, the local softness and the dual descriptor. In this work, we show how these nonlocal indices provide a quantum chemical basis to explain the success of qualitative resonance models in chemical reactivity predictions. Also, local information is implicitly contained as CDFT indices are obtained by simple integration. As illustrative examples, we have considered in this work the Markovnikov's rule, the reactivity of enolate anion, the nucleophilic conjugate addition to α,β‐unsaturated compounds and the electrophilic aromatic substitution of benzene derivatives. The densities used in this work were obtained with Hartree‐Fock, Kohn‐Sham DFT, and singles and doubles configuration interaction (CISD) approaches. © 2012 Wiley Periodicals, Inc.
Electrochemical Behaviours and Detection of Adenosine‐5¢‐triphosphate on an Ionic Liquid Modified Carbon Paste Electrode
Authors: Niu Qing‐juan , Liu Jun , Li Guang‐jiu , Qin Hong‐qing , Gao Hong‐wei , Sun Wei
Published: March 2012

In this paper a new electrochemical method based on the ionic liquid modified carbon paste electrode (IL‐CPE) was proposed for the determination of adenosine‐5′‐triphosphate (ATP) in a pH 4.5 Britton‐Robinson (B‐R) buffer solution. IL‐CPE was prepared by using 1‐butyl‐3‐methylimidazolium trifluoroacetate (BMIMCF3COO) as the modifier. Cyclic voltammetry was used to investigate the electrochemical behaviors of ATP on the IL‐CPE, and the results indicated that IL‐CPE exhibited strong electrocatalytic ability to promote the oxidation of ATP with a single well‐defined irreversible adsorption‐controlled oxidation peak appeared. The electrochemical reaction parameters of ATP were calculated with the results of the electron transfer coefficient (α) as 0.40, the electron transfer number (n) as 1.17, the apparent heterogeneous electron transfer rate constant (ks) as 3.66 × 10‐6 s‐1 and the surface coverage (Γτ) as 2.48 × 10‐9 mol cm‐2. Under the selected conditions the proposed IL‐CPE showed good performances to the ATP detection in the concentration range from 0.1 to 1000.0 μmol L‐1 with the detection limit as 3.65 × 10‐8 mol L‐1 (3σ) by differential pulse voltammetry. The method showed good selectivity to the ATP detection without the interferences of coexisting substances and was successfully applied to the ATP injection samples detection with satisfactory results.
Microwave Promoted, Sodium Acetate Catalyzed One Pot Synthesis of Poly Functionalized 4H‐Pyrans
Authors: Pandharpatte Mahesh Shivaji , Mulani Khudbudin Baban , Mohammed Nazeruddin Nasiruddin Gulam
Published: March 2012

A clean and efficient one pot synthesis of 4H‐pyran derivatives through condensation of aromatic aldehydes, malononitrile and dicarbonyl compounds under microwave irradiation in presence of Sodium acetate as a catalyst is described.
Structure and Dielectric Properties of NiTiO3 Powders Synthesized by the Modified Sol–Gel Method
Authors: Chuang Shiow‐Huey , Hsieh Min‐Lung , Wang Ding‐Yeong
Published: March 2012

This study reports the synthesis of nickel titanate (NiTiO3) powders by using the modified sol‐gel method, with nickel acetate tetrahydrate as the nickel source, titanium isopropoxide as the titanium source, and 2‐methoxyethanol as the solvent, followed by post‐heat treatment in air at temperatures ranging from 500 °C to 900 °C. The characteristics of powders were determined by X‐ray diffraction (XRD), FT‐infrared spectroscopy (FT‐IR), ultraviolet/visible spectroscopy (UV/Vis), and Raman spectroscopy. The particle size and surface area of the powders were also measured. The results indicated that single‐phase NiTiO3 can be prepared using the modified sol‐gel method, followed by post‐heat treatment at the relatively low temperature of 550 °C. The crystallite sizes and particle sizes of NiTiO3 powders increase in conjunction with the post‐heat treatment temperatures. However, the surface area of the powders shrinks as the post‐heat treatment temperatures increase. The dielectric constants of NiTiO3 powders, based on the capacitance‐voltage analysis, are within a range of 13.2 to 17.8.
Low density lipoprotein receptor‐related protein 1 modulates the proliferation and migration of human hepatic stellate cells
Authors: Llorente‐Cortes V. , Barbarigo V. , Badimon L.
Published: March 2012

Human hepatic stellate cells (HHSCs) proliferation and migration play a key role in the pathogenesis of liver inflammation and fibrogenesis. Low density lipoprotein receptor‐related protein (LRP1) is an endocytic receptor involved in intracellular signal transduction. The aim of this work was to analyse the role of low density lipoprotein receptor‐related protein (LRP1) in HHSCs proliferation and migration and the mechanisms involved. Human LRP1 deficient‐HHSCs were generated by nucleofecting the line HHSCs with siRNA anti‐LRP1. HHSCs DNA synthesis was measured by [3H]‐thymidine incorporation and cell cycle progression by flow cytometry after annexin V and iodure propidium staining. Cell migration was assessed using a wound repair model system. LRP1 expression and extracellular matrix‐regulated kinase (ERK1,2) phosphorylation were analysed by Western blot analysis. Transforming growth factor‐β (TGF‐β) extracellular levels were analysed by ELISA. siRNA‐antiLRP1 treatment almost completely inhibited LRP1 mRNA and protein expression. LRP1 deficient HHSCs showed higher proliferative response (172 ± 19 vs. 93 ± 8 [3H]‐thymidine incorporation; 78.68% vs. 82.69% in G0/G1, 21.32% vs. 17.30% in G2/S) and higher migration rates than control HHSCs. LRP1 deficient cells showed higher levels of phosphorylated ERK1,2. TGF‐β extracellular levels were threefold higher in LRP1‐deficient than in control HHSCs cells. These results demonstrate that LRP1 regulates HHSCs proliferation and migration through modulation of ERK1,2 phosphorylation and TGF‐β extracellular levels. These results suggest that HHSCs‐LRP1 may play a key role in the modulation of factors determining hepatic fibrosis. J. Cell. Physiol. 227: 3528–3533, 2012. © 2012 Wiley Periodicals, Inc.
Protein sequences involved in the mitochondrial import of the 3,5,3′‐L‐triiodothyronine receptor p43
Authors: Carazo Angel , Levin Jonathan , Casas François , Seyer Pascal , Grandemange Stéphanie , Busson Muriel , Pessemesse Laurence , Wrutniak‐Cabello Chantal , Cabello Gérard
Published: March 2012

The major effect of T3 on mitochondrial activity has been partly explained by the discovery of p43, a T3‐dependent transcription factor of the mitochondrial genome. P43 is imported into mitochondria in an atypical manner which is not yet fully understood. Our aim was to characterize the p43 sequences inducing its mitochondrial import, using in organello import experiments with wild‐type or mutated proteins and validation in CV1 cells. We find that several sequences define the mitochondrial addressing. Two alpha helices in the C‐terminal part of p43 are actual mitochondrial import sequences as fusion to a cytosolic protein induces its mitochondrial translocation. Helix 5 drives the atypical mitochondrial import process, whereas helices 10/11 induce a classical import process. However, despite its inability to drive a mitochondrial import, the N‐terminal region of p43 also plays a permissive role as in the presence of the C‐terminal import sequences different N‐terminal regions determine whether the protein is imported or not. These results can be extrapolated to other mitochondrial proteins related to the nuclear receptor superfamily, devoid of classical mitochondrial import sequences. J. Cell. Physiol. 227: 3768–3777, 2012. © 2012 Wiley Periodicals, Inc.
Establishment of keratinocyte colonies from small‐sized cervical intraepithelial neoplasia specimens
Authors: Bononi Ilaria , Bosi Silvia , Bonaccorsi Gloria , Marci Roberto , Patella Alfredo , Ferretti Stefano , Tognon Mauro , Garutti Paola , Martini Fernanda
Published: March 2012

The size of human cervical intraepithelial neoplasia (CIN) biopsies is usually very small and standard methods do not allow an adequate number of keratinocytes to be isolated for culturing purposes. In this study, a new approach to establish keratinocyte cultures from small CIN a tissue fragments was developed. Neoplastic specimens and corresponding normal tissues, which were used as controls, were digested with collagenase. Tissue‐derived fibroblasts and keratinocytes were co‐cultured in calcium and serum medium. Single keratinocyte colonies from primary cultures were expanded using a culture medium optimized in our laboratory. Primary keratinocyte colonies, as well as expanded colonies, were tested for epithelial and cervical markers such as 5, 14, 17, and 19 keratins, and p63 by immunofluorescence. Our results indicate that a variable number of primary keratinocyte colonies could be detected in neoplastic cultures, depending on the grade of cervical lesions from which the colonies originated. Single colonies, when cultured with our new medium, grew at a high rate with uniform size and morphology for some passages. Epithelial and p63 markers were expressed in keratinocyte colonies, as well as in expanded colonies. In conclusion, our study reports a rapid and easy culturing system which enables keratinocyte colonies from minute cervical tumor tissues to be obtained. Moreover, using the new culture medium, keratinocyte colonies can be expanded at a high proliferative rate. J. Cell. Physiol. 227: 3787–3795, 2012. © 2012 Wiley Periodicals, Inc.
Micro‐ and nanostructures of iridescent wing scales in purple emperor butterflies (Lepidoptera: Apatura ilia and A. iris)
Authors: Ćurčić Srećko B. , Pantelić Dejan V. , Ćurčić Božidar P.M. , Savić‐Šević Svetlana N. , Makarov Slobodan E. , Lačković Vesna B. , Labudović‐Borović Milica M. , Ćurčić Nina B. , Stojanović Dejan V.
Published: March 2012

Apatura ilia (Denis and Schiffermüller, 1775) and A. iris (Linnaeus, 1758) are fascinating butterflies found in the Palaearctic ecozone (excepting the north of Africa). The wings of these insects are covered with a great number of two types of scales positioned like roof tiles. Type I scales are on the surface, while type II scales are situated below them. The structural color of the type I scales is recognized only on the dorsal side of both the fore and hind wings of the males of the aforementioned species. Both types of scales are responsible for pigment color of the wings, but iridescence is observed only in the type I scales. The brilliant structural color is due to a multilayer structure. The features of the scales, their dimensions and fine structure were obtained using scanning electron microscopy. Cross sections of the scales were then analyzed by transmission electron microscopy. The scales of the “normal” and clytie forms of A. ilia have a different nanostructure, but are of the same type. A similar type of structure, but with a different morphology, was also noticed in A. iris. The scales of the analyzed species resemble the scales of tropical Morpho butterflies. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
Correlation of perfusion parameters on dynamic contrast‐enhanced MRI with prognostic factors and subtypes of breast cancers
Authors: Koo Hye Ryoung , Cho Nariya , Song In Chan , Kim Hyeonjin , Chang Jung Min , Yi Ann , Yun Bo La , Moon Woo Kyung
Published: March 2012

Purpose:

To investigate whether a correlation exists between perfusion parameters obtained from dynamic contrast‐enhanced (DCE) magnetic resonance imaging (MRI) and prognostic factors or immunohistochemical subtypes of breast cancers.

Materials and Methods:

Quantitative parameters (Ktrans, kep, and ve) of 70 invasive ductal carcinomas were obtained using DCE‐MRI as a postprocessing procedure. Correlations between parameters and prognostic factors, including tumor size, axillary nodal status, histologic grade, nuclear grade, expression of estrogen receptor (ER), progesterone receptor (PR), Ki‐67, p53, bcl‐2, and human epidermal growth factor receptor 2 (HER2) and subtypes categorized as luminal (ER or PR‐positive), triple negative (ER or PR‐negative, HER2‐negative), and HER2 (ER and PR‐negative, HER2 overexpression) were analyzed.

Results:

Mean Ktrans was higher in tumors with a high histologic grade than with a low histologic grade (P = 0.007), with a high nuclear grade than with a low nuclear grade (P = 0.002), and with ER negativity than ER positivity (P = 0.056). Mean kep was higher in tumors with a high histologic grade than with a low histologic grade (P = 0.005), with a high nuclear grade than with a low nuclear grade (P = 0.001), and with ER negativity than with ER positivity (P = 0.043). Mean ve was lower in tumors with a high histologic grade than with a low histologic grade (P = 0.038) and with ER negativity than with ER positivity (P = 0.015). Triple‐negative cancers showed a higher mean kep than the luminal type (P = 0.015).

Conclusion:

Breast cancers with higher Ktrans and kep, or lower ve, had poor prognostic factors and were often of the triple‐negative subtype. J. Magn. Reson. Imaging 2012;36:145–151. © 2012 Wiley Periodicals, Inc.
The diagnostic value of nipple discharge cytology: Breast imaging complements predictive value of nipple discharge cytology
Authors: Kalu Ogori N. , Chow Cassandra , Wheeler Amanda , Kong Christina , Wapnir Irene
Published: March 2012

Background

Papilloma is the most common finding associated with pathologic nipple discharge. In the absence of breast imaging abnormalities, the incidence of occult malignancy is <3%.

Objective

To determine the predictive value of nipple discharge cytology in conjunction with breast imaging.

Methods

Retrospective review of 160 charts; inclusion criteria of clinically pathologic nipple discharge, subsequent excisional biopsy, and absence of palpable abnormalities. Nipple discharge cytology categorized as negative, atypical, suspicious, and papillary. Breast imaging was analyzed. Preoperative tests were correlated to final surgical pathology.

Results

89 patients identified. Sixty‐five had positive cytology, with a false positive rate of 32.3%. They were associated with papillomas in 52%, benign non‐papillary in 33% and malignant lesions in 9% of cases. Nipple discharge cytology was positive in 69.6% of papillomas and 92% of atypical/malignant lesions; 30% had abnormal breast imaging and positive cytology. Nipple discharge cytology had a sensitivity of 74.5%, specificity of 30%, and positive predictive value of 68%. The positive predictive value increased to 85% with associated abnormal breast imaging.

Conclusions

Nipple discharge cytology is useful in evaluating pathologic discharge. However, negative cytology with negative imaging is not enough to avoid surgery in cases of suspicious clinical presentation. J. Surg. Oncol. 2012; 106:381–385. © 2012 Wiley Periodicals, Inc.
Capital City Museums and Tourism Flows: an Empirical Study of the Museum of New Zealand Te Papa Tongarewa
Authors: Carey Simon , Davidson Lee , Sahli Mondher
Published: March 2012

This study uses time series analysis to explore the extent to which the opening of the Museum of New Zealand in 1998 contributed to tourism growth in the nation's capital, Wellington. With the use of a series of different measures for tourism and major events in the city, econometric regressions are undertaken to better understand the relationship between visitors to the museum and tourism growth in the city's short‐term commercial accommodation sector. The findings are consistent with the museum having a positive impact on tourist arrivals and overnight stays. These results contribute valuable empirical evidence of the positive role of museums in attracting tourists to urban centres. Copyright © 2012 John Wiley & Sons, Ltd.
Resource partitioning among cape foxes, bat‐eared foxes, and black‐backed jackals in South Africa
Authors: Kamler Jan F. , Stenkewitz Ute , Klare Unn , Jacobsen Nicolas F. , Macdonald David W.
Published: March 2012

Cape foxes (Vulpes chama) and bat‐eared foxes (Otocyon megalotis) are sympatric with black‐backed jackals (Canis mesomelas) over much of southern Africa, although competition with and/or predation by jackals may suppress local populations of both fox species. From 2005 to 2008, we captured, radio‐collared, and monitored 11 cape foxes, 22 bat‐eared foxes, and 15 black‐backed jackals on a game ranch in South Africa to investigate their spatial, habitat, temporal, and dietary resource overlap. Mean annual home‐range sizes were 27.7 km2for cape foxes, 5.0 km2for bat‐eared foxes, and 17.8 km2for jackal family groups. Home ranges overlapped completely between species, although core areas overlapped less (<45%), with cape foxes and jackals overlapping the least (12%). When active, cape foxes, but not bat‐eared foxes, used core areas of jackal groups less than expected. Additionally, both fox species used jackal core areas less than expected for their den sites, suggesting areas outside jackal core areas were used as refuges by foxes. Strong levels of habitat partitioning were not apparent at the study site or home‐range levels, although habitat selection for den sites differed between jackals and cape foxes. Jackals were the most diurnal across seasons, whereas cape foxes were the most nocturnal. Diets overlapped little (R0 = 0.20–0.34) among the canid species, with bat‐eared foxes overlapping the least with the others. Jackals killed at least 5 collared bat‐eared foxes and 1 collared cape fox, indicating potential interference competition, probably for exclusive use of territorial space rather than over shared resources. We conclude that bat‐eared foxes coexisted with jackals primarily by their dietary specialization and group living. Cape foxes coexisted with jackals by exhibiting high levels of spatial, habitat, temporal, and dietary partitioning. Surprisingly, the fox species exhibited positive associations with each other. Our results show the mechanisms that may allow jackals to suppress fox populations, yet also show how foxes, in turn, use different mechanisms to coexist with a dominant canid. © 2012 The Wildlife Society.
THREE‐STAGE ANALYSIS OF THE ADOPTION OF SOIL AND WATER CONSERVATION IN THE HIGHLANDS OF RWANDA
Authors: Bizoza A. R.
Published: March 2012

This paper investigates the adoption of bench terraces by applying a three‐stage analysis using data from 301 households in the highlands of Rwanda. Ongoing adoption of bench terraces is ‘unpacked’ to consider both adopters willing to retain and increase the intensity of using terraces already constructed and new adopters willing to develop new bench terraces. Results suggest that farmers' inability to maintain existing terraces may explain the reluctance to adopt new terraces. The same inability explains why some of the terraces constructed earlier are not well maintained and fully used by farmers in northern and southern Rwanda. Policy actions aimed at improving farmer's capacity to invest in complementary inputs will sustain future generations of soil and water conservation measures in Rwanda. Copyright © 2012 John Wiley & Sons, Ltd.
Polyelectrolyte Capsules as Carriers for Growth Factor Inhibitor Delivery to Hepatocellular Carcinoma
Authors: Baldassarre Francesca , Vergaro Viviana , Scarlino Flavia , De Santis Flavia , Lucarelli Giovanna , Torre Antonio della , Ciccarella Giuseppe , Rinaldi Ross , Giannelli Gianluigi , Leporatti Stefano
Published: March 2012

The efficient internalization of TGF‐beta inhibitor‐loaded polyelectrolyte capsules and particles is studied in two HCC cell lines. Two polyelectrolyte pairs (biocompatible but not degradable and biodegradable crosslinked with gluteraldehyde) are employed for coating. The capsules are characterized by SEM. LY is successfully loaded inside the core and embedded between polymer layers. MS is used to quantify the loading efficiency by comparing post‐loading and core‐loading methods, since both coated templates and hollow shells are used as carriers. CLSM confirms dissolution of the pre‐formed multilayer upon enzymatic degradation as the method of release, and migration assays demonstrate a higher inhibition efficiency of TGF‐beta in tailored biodegradable capsules compared to free LY administration.

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Nanopaper: Thin Films Prepared from Polymeric Nanotubes
Authors: Huang Bin , Hill Reghan , van de Ven Theo
Published: March 2012

A novel mesoporous material (“nanopaper”) prepared from template‐synthesized, polyelectrolyte‐stabilized polymer nanotubes is reported. The stacked network of completely collapsed, flat nanotubes forms the porous structure, which has a water‐vapor permeability that can be tuned by the stabilizer. The transport mechanism is elucidated based on microscopy, thermal analysis, spectroscopy characterization, and mass‐transfer theory. The results suggest that the nanotube surface plays a key role in the through‐film transport process. This effect vanishes in the more open films formed from micro‐fibrillated cellulose having similar fibril diameters. Nanopaper mechanical properties are also reported. With a pore structure and functionality that can be varied, nanopaper is a promising functional membrane.

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A New Flame Retardant for Wood Materials Tested in Wood‐Plastic Composites
Authors: Seefeldt Henrik , Braun Ulrike
Published: March 2012

A new flame retardant based on an ammonium phosphonate is studied with respect to its thermal decomposition and its mode of action in wood‐plastic composites (WPCs). The measurements are carried out by means of fire tests (cone calorimeter) and pyrolysis investigations (thermogravimetry, infrared spectroscopy). The flame retardant acts mainly in the condensed phase by increasing the amount of residue formed by the wood part in the WPC. Additional flame dilution is achieved by the release of water, ammonia and carbon dioxide during the decomposition of the flame retardant.

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A Study on Transreactions of PET/PEN Reactive Blending in a Twin‐Screw Extruder Using an Axial Dispersion Model
Authors: Khonakdar Hossein Ali , Golriz Mahdi , Jafari Seyed Hassan , Abedini Hossein , Wagenknecht Udo , Heinrich Gert
Published: March 2012

Transreactions of PET and PEN melt‐mixed in a twin‐screw extruder are investigated. The extruder is modeled and characterized in the frame of a tubular system of closed type. The kinetic modeling is based on a modified second‐order reversible reaction equation, which allows the dispersion equation to be solved analytically. The analysis shows a good agreement between the model and experiment. The axial dispersion model is employed to predict the extent of transesterification reactions (X) and degree of randomness (RD). 1H NMR measurements are performed to estimate X and RD. Theoretical and experimental data are in good agreement. The model can thus be exploited to describe the effects of processing parameters, mixing time, mixing temperature, and blend composition on X and RD.

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