bluuebunny/crossref_metadata_2025 huggingface dataset:
Self‐assembly of pH and calcium dual‐responsive peptide‐amphiphilic hydrogel
Authors: Zhou Xi‐Rui , Ge Rui , Luo Shi‐Zhong
Published: October 2013

Peptide‐based hydrogels have gained much interest for biomedical applications as a result of their biocompatibility. Herein, we reported a synthetic pH‐sensitive and calcium‐responsive peptide‐amphiphilic hydrogel. The sequences of the peptide amphiphiles were derived from the repeat‐in‐toxin (RTX) motif. At a certain peptide‐amphiphile concentration, self‐assembly was accompanied by the formation of a rigid, viscoelastic hydrogel at low pH or the presence of calcium ions. Circular dichroism spectra showed that the peptide amphiphiles adopted beta‐sheet structure. Meanwhile, as revealed by transmission electron microscopy, the peptide‐amphiphile self‐assembly was accompanied by the formation of long interconnected nanofibrillar superstructure. Material properties of the resulting peptide‐amphiphile hydrogel were characterized using oscillatory sheer rheology, and the storage modulus (G′) was found to be one order of magnitude higher than the loss modulus (G″), indicating a moderately rigid viscoelastic material. Furthermore, with systematical residue substitution, it was found that the aspartic acid within the repeat‐in‐toxin sequence of peptide amphiphiles was responsible for the pH and calcium selectivity. The environmental responsiveness, secondary structure, morphology, and mechanical nature of the peptide‐amphiphile hydrogel make it a possible material candidate for biomedical and engineering application. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd.
Two‐color lasing in a coupled multilayer cavity with InAs quantum dots by optical pumping
Authors: Kitada Takahiro , Harayama Chiho , Morita Ken , Isu Toshiro
Published: October 2013

Two‐color lasing in a GaAs/AlAs coupled multilayer cavity has been studied for a novel type of terahertz emitting devices. In the structure, two cavity layers based on GaAs were connected by the intermediate GaAs/AlAs distributed Bragg reflector multilayer and three layers of self‐assembled InAs quantum dots (QDs) were inserted only in the top‐side cavity layer as optical gain materials. The broadened QD emissions around 1.25 µm are very useful to realize the optical gain because they could cover the wide range of the mode frequency difference. Two mode emissions with an optical frequency difference of 3.2 THz were successfully demonstrated under room temperature cw operation by optical pumping. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Fabrication and analysis of current confinement structure for photonic crystal laser
Authors: Yamauchi S. , Morifuji M. , Kondow M.
Published: October 2013

We recently proposed a laser structure with a circularly arranged cavity structure with AlOx with the aim of fabricating an electrically driven photonic crystal (PC) laser. Fabricating our proposed laser requires carrier injection to the cavity. In this study, we fabricated and investigated the current confinement structure for our proposed PC laser and established a process for fabricating the structure. We were able to apply current to a funnel and measure the current‐voltage characteristics of the structure. The electrical characteristics showed an ohmic feature, showing the possibility of fabricating our proposed PC laser. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Changing photoluminescence spectra of graphene oxide by centrifugation treatments
Authors: Kozawa Daichi , Miyauchi Yuhei , Mouri Shinichiro , Matsuda Kazunari
Published: October 2013

We conducted continuous‐wave photoluminescence (PL) measurements to study optical properties of graphene oxide (GO) before and after a centrifugation treatment. The pristine GOs show a PL peak around near‐infrared (NIR) region (∼1.7 eV). In contrast, the centrifuged GOs exhibit PL peaks at blue (∼2.8 eV) and UV (∼4.1 eV) region. The difference among the emission features in the pristine and centrifuged GOs originates from the change of major structure from the sp2 clusters to the quasi‐molecular structure. Our findings indicate tunability of PL from GOs in the range from NIR to UV region by the centrifugation treatment. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Enhancing carrier mobility of IGZO TFT fabricated by non‐vacuum mist CVD with O3 assistance
Authors: Kawaharamura Toshiyuki , Uchida Takayuki , Wang Dapeng , Sanada Masaru , Furuta Mamoru
Published: October 2013

Recently, we succeeded in demonstrating an oxide TFT consisting of a channel layer (IGZO) and gate insulator (AlOx) continuously fabricated by non‐vacuum mist CVD. In this report, each thin film and the interfaces of the films have been improved with ozone (O3) assistance, as the initial oxide TFT had poor characteristics compared with those of the IGZO TFT fabricated by the conventional vacuum process. A superhydrophilic interface between AlOx and IGZO was obtained by removing the adhered organic matter from the film surface. The breakdown fields (EBD) and dielectric constant (κ) of the AlOx thin films were improved from 6 to 8 MV/cm and from 6 to 7, respectively, and the carrier concentration of the IGZO thin film decreased from 1019 to 1016 cm–3. The oxide TFT exhibited field effect mobility (μlin) of 8.7 cm2/(Vs), sub‐threshold slope (S) of around 0.3 V/dec. and hysteresis (ΔVH) of around 0.5 V. These values were obtained by improving each thin film and the interfaces of the films with O3 assistance. This result is an important first step toward non‐vacuum oxide TFT fabrication processes. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
First‐principles study of oxygen‐doping states in II‐VI semiconductors
Authors: Ishikawa Masato , Nakayama Takashi
Published: October 2013

Oxygen doping into zinc‐family II‐VI semiconductors is studied by the first‐principles calculation. We found that a large band‐gap reduction occurs for ZnS and ZnSe, while there is little reduction and appears a deep level of oxygen in the band gap for ZnTe. It is shown that such difference reflects the order of energy positions of host cation (Zn) 4s‐orbital and oxygen (O) 3s‐orbital states. We also study the electronic states and stability of oxy‐gen pair. By calculating the formation energy of O pair, we found that O dopants prefer to locate isolated. This is because O atom has so small radius that the pairing pro‐motes a large elastic strain in host system, which feature is in contrast to the case of N pair in III‐V systems.
Surface morphology of multilayer graphene synthesized directly on silicon dioxide
Authors: Katakura Kenta , Tomori Hikari , Ootuka Youiti , Kanda Akinobu
Published: October 2013

We report the surface morphology of multilayer graphene synthesized directly on a SiO2/Si substrate through graphitization of amorphous carbon with Ni catalyst. We demonstrate that the disorder‐induced Raman D peak is effectively suppressed when the Ni catalyst layer is covered with Au layer. Scanning electron microscope observation reveals that the Au layer prevents granulation of Ni after the annealing process, leading to the formation of continuous graphene with less holes. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Broadband emission centered at ∼1 µm with a Gaussian‐like spectrum by stacking In‐flushed QD layers
Authors: Ozaki Nobuhiko , Hino Yuji , Ohkouchi Shunsuke , Ikeda Naoki , Sugimoto Yoshimasa
Published: October 2013

We have grown a stack of In‐flushed InAs quantum dot (QD) layers to realize a broadband emission centered at ∼1 µm with a Gaussian‐like spectrum as a light source for optical coherence tomography (OCT). The In‐flush process, which enables control of the height of the QD, was optimized to control the emission wavelength and intensity of self‐assembled InAs/GaAs QDs. A partial capping layer of GaAs was deposited on as‐grown InAs/GaAs QDs with various thicknesses (dcap), and a rapid annealing of the sample was executed with the proper annealing temperature. By optimizing dcap and the annealing temperature for each QD layer, a broadband Gaussian‐like spectrum with a 102‐nm‐bandwidth was obtained. The coherence function of the emission spectrum exhibits a 4.5‐µm axial resolution for OCT images without distinct side lobes. These results demonstrate the effectiveness of the In‐flushed QDs as a light source to obtain high‐quality OCT images. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The influence of temperature on the recombination processes in blue and green InGaN LEDs
Authors: Crutchley Benjamin G. , Marko Igor P. , Sweeney Stephen J.
Published: October 2013

A temperature dependent investigation into the efficiency droop effect in blue and green InGaN light‐emitting diodes (LEDs) is presented. The efficiency droop effect is observed to be the strongest at low temperatures in both blue and green LEDs. We show such behaviour is consistent with a reduced hole injection rate resulting in an increased concentration of electron leakage from the quantum wells. Spectral measurements demonstrate that the emission peak has an “s‐shape” dependence on tem‐perature and a full‐width at half‐maximum which increases with decreasing temperature below 100 K. Such observations indicate the importance of carrier localization in the InGaN LEDs. At temperatures where hole injection is not problematic the efficiency droop is the result of carrier delocalization and subsequent defect related recombination with increasing current injection. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Polymer‐free, low tension graphene mechanical resonators
Authors: Alemán Benjamín , Rousseas Michael , Yang Yisheng , Regan Will , Crommie Michael , Wang Feng , Zettl Alex
Published: October 2013

Graphene resonators are fabricated using a polymer‐free, direct transfer method onto metal reinforced holey carbon grids. The resonators are distinguished by the absence of organic residues and excellent crystallinity. The normal mode frequencies are measured using a Fabry–Perot technique; resonance curves indicate highly linear behaviour but very little built‐in strain, which is consistent with device geometry examined by atomic force microscopy. We conclude that the oscillators' restoring force is due instead to graphene's intrinsic bending rigidity; our measurements indicate a value of approximately 1.0 eV, consistent with previous theoretical and experimental work. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Strained graphene as a local probe for plasmon‐enhanced Raman scattering by gold nanostructures
Authors: Heeg Sebastian , Oikonomou Antonios , Garcia Roberto Fernandez , Maier Stefan A. , Vijayaraghavan Aravind , Reich Stephanie
Published: October 2013

We investigate with Raman spectroscopy how gold nanostructures of different shape, size and geometry locally modify a graphene cover layer through strain. The resulting phonon softening translates into frequency downshifts of up to 85 cm–1 for the 2D‐mode of graphene. With spatially resolved and excitation dependent Raman measurements we demonstrate that the downshifted Raman peaks exclusively arise from strained graphene subject to plasmonic enhancement by the nanostructures. The signals arise from an area well below the size of the laser spot. They serve as a local probe for the interaction between graphene and intense light fields. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Chemical vapor deposition of graphene on silver foil as a tarnish‐resistant coating
Authors: Ayhan Muhammed Emre , Kalita Golap , Sharma Subash , Tanemura Masaki
Published: October 2013

Here, we demonstrate the synthesis of graphene on Ag foil by an atmospheric‐pressure (AP) chemical vapor deposition (CVD) process as tarnish‐resistant coating. Synthesis of a continuous graphene film on Ag foil is achieved using the solid camphor as carbon precursor in a gas mixture of Ar and H2. Tarnishing of the Ag surface through sulfidation is investigated with and without coating of the graphene film. It is observed that the bare Ag surface immediately reacts with sulfur vapor to turn black, whereas graphene coating passivates the Ag surface robustly and thereby restrains the sulfur reaction to preserve from tarnishing. Our findings show that a large‐area graphene film can be effectively grown on Ag surface by a CVD process as a tarnish and corrosion resistance barrier.

magnified image

Synthesis of graphene structure on Ag foil by an AP‐CVD process as a tarnish‐resistant coating.

(© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Liquiritigenin Restores Osteoblast Damage through Regulating Oxidative Stress and Mitochondrial Dysfunction
Authors: Choi Eun Mi , Suh Kwang Sik , Lee Young Soon
Published: October 2013

We investigated the protective effect of liquiritigenin, one of the flavonoids present in Glycyrrhizae radix, against antimycin A‐induced mitochondrial dysfunction in MC3T3‐E1 osteoblast cells. Osteoblastic MC3T3‐E1 cells were pre‐incubated with liquiritigenin before treatment with antimycin A, and markers of mitochondrial function and oxidative damage were examined. In addition, the effects of liquiritigenin on the activation of phosphoinositide 3‐kinase (PI3K) were examined in MC3T3‐E1 cells. Liquiritigenin protected MC3T3‐E1 cells from antimycin A‐induced cell death. However, the PI3K inhibitor, LY294002, significantly attenuated liquiritigenin‐mediated cell survival, indicating the involvement of PI3K in the cytoprotective effect of liquiritigenin. Pretreatment with liquiritigenin prior to antimycin A exposure significantly reduced antimycin A‐induced PI3K inactivation, mitochondrial membrane potential dissipation, complex IV inactivation, and ATP loss. Liquiritigenin also reduced mitochondrial superoxide generation, nitrotyrosine production, and cardiolipin peroxidation during mitochondrial complex inhibition with antimycin A. Taken together, the results of this study show that modulation of PI3K, antioxidant effects, and the attenuation of mitochondrial dysfunction by liquiritigenin represent an important mechanism for its protection of osteoblasts against cytotoxicity resulting from mitochondrial oxidative stress. Copyright © 2013 John Wiley & Sons, Ltd.
Comparative study of sialyl glycoprotein with multiple glycosylation sites using isotope labeling and capillary liquid chromatography/mass spectrometry
Authors: Ma Yi‐Chun , Lin Chih‐Yu , Her Guor‐Rong
Published: October 2013

RATIONALE

A comparative strategy has been demonstrated using RNase B, a single‐site N‐linked high‐mannose glycoprotein. Glycoproteins are more common with multiple glycosylation sites and with complex glycans. A strategy capable of differentiating the changes caused by glycoprotein concentration, glycosylation site occupancy, and a glycoform profile of complex glycoproteins would be beneficial.

METHODS

Tryptic‐digested glycoproteins were labeled using 12C,H‐formaldehyde and 13C, D‐formaldehyde, purified, and then analyzed using capillary reversed‐phase liquid chromatography/mass spectrometry (RPLC/MS). The relative intensity of non‐glycosylated peptides provided information on glycoprotein concentration variation. A site‐specific glycoform profile variation was obtained by comparing the glycoform profile of CH2 and 13CD2 glycopeptides. Determining the protein concentration and glycoform profile variations allows the glycosylation site occupancy variation to be calculated.

RESULTS

A strong correlation between the observed and prepared ratios for fetuin glycopeptides from 0.2 to 5 was obtained. Two fetuin samples with different glycoprotein concentrations (4‐fold change), glycoform profiles (normal and modified), and glycosylation site occupancies (100% and 50%) were prepared, labeled, mixed, purified, and analyzed using RPLC/MS. The results of the comparative study had a strong correlation with the prepared values.

CONCLUSIONS

In this report, we demonstrated a comparative analysis of fetuin, a glycoprotein with multiple glycosylation sites and complex sialyl glycans. Compared to our previous approach, we made several modifications including the use of RPLC, a larger mass difference isotope tag, and isotope overlapping correction. The modified approach is expected to be applicable to most glycoproteins. Copyright © 2013 John Wiley & Sons, Ltd.
Quantitative determination of poly(amidoamine) dendrimers in urine by liquid chromatography/electrospray ionization hybrid quadrupole linear ion trap mass spectrometry
Authors: Uclés Ana , Martínez Bueno María Jesús , Ulaszewska Maria Malgorzata , Hernando María Dolores , Ferrer Carmen , Fernández‐Alba Amadeo R.
Published: October 2013

RATIONALE

Dendrimer nanocarriers have become of increasing interest in the field of biomedicine for their drug delivery potential. Surface modifications and optimized nanosize control are the strategies being followed to enhance drug delivery efficacy and renal clearance, especially for dendrimers of a lower generation number. The aim of this study was the development and performance evaluation of an analytical method for the quantitative determination of polyamidoamine (PAMAM) dendrimers in urine.

METHODS

PAMAM dendrimers (generations G0 to G3) were analyzed using liquid chromatography/electrospray ionization hybrid quadrupole linear ion trap mass spectrometry (LC/ESI‐QqLIT‐MS). Quantitative analysis was performed in selected reaction monitoring (SRM) mode. To confer a higher degree of confidence on the identification of PAMAM dendrimers, an SRM scan and collision‐induced dissociation (CID), as a dependent scan, were performed in one single run using the information‐dependent acquisition (IDA) mode.

RESULTS

The LC/ESI‐QqLIT‐MS method, in SRM mode, allowed quantitative determination in urine matrix with good repeatability and reproducibility (relative standard deviation (R.S.D.) from 2 to 15%), linearity (R >0.99) over the concentration range (6∙10–4 to 5∙10–2 mmol.L–1), and sensitivity within the micromolar range. The detection limit values were above 1∙10–4 mmol.L–1 in both solvent and urine, for the generations studied.

CONCLUSIONS

The developed method has demonstrated a capability for the identification and quantification of PAMAM dendrimer nanoparticles in a complex liquid matrix. The use of an LC/ESI‐QqLIT‐MS system, of modest m/z range and unit resolution, offers an alternative in the analysis of lower generation PAMAM dendrimers between mass analyzers of higher resolution and the conventional LC‐UV method that is commonly applied for dendrimer quantification, but which lacks sufficient identification capacity. Copyright © 2013 John Wiley & Sons, Ltd.
Gas chromatography/mass spectrometry analysis of the six‐ring regioisomeric dimethoxybenzyl‐N‐methylpiperazines (DMBMPs)
Authors: Abdel‐Hay Karim M. , DeRuiter Jack , Clark C. Randall
Published: October 2013

RATIONALE

Piperazine‐based designer drugs represent a novel class of substances found in illicit drug samples in the US and abroad. The clandestine production of these substances often makes use of piperazine as a key commercially available precursor substance. The commercial availability of 1‐methylpiperazine suggests additional designer modification based on this additional precursor material.

METHODS

This study focuses on the electron ionization mass spectrometric (EI‐MS) fragmentation of the dimethoxybenzyl‐N‐methylpiperazines as potential designer modifications of the general benzylpiperazine drug skeleton and explores the gas chromatography (GC)/MS properties of all six of these regioisomeric substances.

RESULTS

Fragmentation of the bond between the benzylic carbon and the adjacent piperazine nitrogen provides the base peak in all six spectra. The internal fragmentation within the piperazine ring produces a number of unique ions in the mass spectra of these dimethoxybenzyl‐N‐methylpiperazines. The migration of methyl groups from nitrogen and oxygen were confirmed by deuterium‐labeling experiments.

CONCLUSIONS

The six regioisomeric dimethoxybenzyl‐N‐methylpiperazines yield equivalent fragment ions and deuterium labeling confirmed the elemental composition of the characteristic fragments in their mass spectra. Mixtures of the dimethoxybenzyl‐N‐methylpiperazines were successfully resolved via capillary gas chromatography using a relatively polar stationary phase and temperature‐programming conditions. Copyright © 2013 John Wiley & Sons, Ltd.
Phosphorus and sulfur metabonomic profiling of tissue and plasma obtained from tumour‐bearing mice using ultra‐performance liquid chromatography/inductively coupled plasma mass spectrometry
Authors: Thompson David F. , Michopoulos Filippos , Smith Christopher J. , Duckett Catherine J. , Wilkinson Robert W. , Jarvis Philip , Wilson Ian D.
Published: October 2013

RATIONALE

Metabonomic studies use complex biological samples (blood plasma/serum, tissues, etc.) that when analysed with high‐performance liquid chromatography/mass spectrometry (HPLC/MS) or nuclear magnetic resonance (NMR) generate profiles that may contain many thousands of features. These profiles can be difficult to interpret with the majority of the features contributing little to the study. As such there is an argument for the development of techniques that can simplify the problem by targeting particular classes of compounds.

METHODS

In this study ultra‐performance liquid chromatography/inductively coupled plasma mass spectrometry (UPLC/ICP‐MS) was used to profile tumour tissue and plasma samples for phosphorus‐ and sulfur‐containing metabolites. These samples were xenograft tumours (derived from breast, lung and colon cell lines) and plasma obtained from nude mice. Plasma was also obtained from non‐tumour‐bearing mice as a control. Due to isobaric interferences this method took advantage of the dynamic reaction cell within the ICP‐MS system to react the phosphorus and sulfur ions with oxygen. The PO+ and SO+ ions were then monitored free of interferences. The total phosphorus and sulfur within each sample was also recorded using flow injection ICP‐MS. A robust quality control system based on pooled sample replicate analysis was used throughout the study.

RESULTS

Determination of the total phosphorus and sulfur content of each sample was sufficient in itself for statistical differentiation between the majority of the cell lines analysed. Subsequent reversed‐phase chromatographic profiling of the organic tumour and plasma extracts revealed the presence of a number of well‐retained phosphorus‐containing compounds that showed tumour‐specific profiles. Reversed‐phase profiling was not suitable for the sulfur‐containing compounds which eluted with the solvent front.

CONCLUSIONS

This study has shown the potential use of UPLC/ICP‐MS to differentiate between tumour cell lines, using both plasma and tumour tissue samples, based solely on metabolites that contain phosphorus or sulfur. Whilst further work is required to identify these compounds this methodology shows the ability of the described methods to provide targets for future biomarker discovery studies. Copyright © 2013 John Wiley & Sons, Ltd.
Comparison of the initial surgical experience with robotic and laparoscopic myomectomy
Authors: Pluchino Nicola , Litta Piero , Freschi Letizia , Russo Marinella , Simi Giovanna , Santoro Anna N. , Angioni Stefano , Gadducci Angiolo , Cela Vito
Published: October 2013

Objective

To compare the initial surgical outcomes of robotic and laparoscopic myomectomy in patients with symptomatic uterine myomas.

Study Design

Retrospective chart review of 86 patients undergoing robotic (RM) (n = 43) or laparoscopic (LM) (n = 43) myomectomy. Data included fibroid characteristics (number, weight, location) layers of uterine reconstruction, operating time, blood loss, complications, and postoperative hospital stay.

Results

No significant differences were noted between RM and LM for fibroid number and weight and mean operating time, although the number of patients receiving at least a double‐layer uterine reconstruction was higher in RM than LM. Blood loss was higher after LM, while no differences resulted in hospital stay.

Conclusion

RM may have some additional advantages compared with LM in terms of bleeding and uterine suturing without compromising operation duration, at least when surgeons were at the beginning of their experience of endoscopic treatment of symptomatic uterine myomas. Copyright © 2013 John Wiley & Sons, Ltd.
Context and Implications Document for: Multiple comprehension strategies instruction in the intermediate grades: three remarks about content and pedagogy in the intervention literature
Authors: Davis Dennis S.
Published: October 2013

This guide accompanies the following article: Dennis S. Davis, Multiple comprehension strategies instruction in the intermediate grades: three remarks about content and pedagogy in the intervention literature, Review of Education, 10.1002/rev3.3005
Control of discrete‐time periodic linear systems with input saturation via multi‐step periodic invariant sets
Authors: Zhou Bin , Li Dewei , Lin Zongli
Published: October 2013

This paper studies local control of discrete‐time periodic linear systems subject to input saturation by using the multi‐step periodic invariant set approach. A multi‐step periodic invariant set refers to a set from which all trajectories will enter a periodic invariant set after finite steps, remain there forever, and eventually converge to the origin as time approaches infinity. The problems of (robust) estimation of the domain of attraction, (robust) local stabilization (with bounded uncertainties), and disturbance rejection are considered. Compared with the conventional periodic invariant set approach, which has been used in the literature for local stability analysis and stabilization of discrete‐time periodic linear systems subject to input saturation, this new invariant set approach is capable of significantly reducing the conservatism by introducing additional auxiliary variables in the set invariance conditions. Moreover, the new approach allows to design (robust) stabilizing periodic controller, in the presence of norm bounded uncertainties, whose period is the same as the open‐loop system and is different from the existing periodic enhancement approach by which the period of the controller is multiple times of the period of the open‐loop system. Several numerical examples are worked out to show the effectiveness of the proposed approach. Copyright © 2013 John Wiley & Sons, Ltd.
Distributed control of linear time‐varying systems interconnected over arbitrary graphs
Authors: Farhood Mazen , Di Zhe , Dullerud Geir E.
Published: October 2013

In this paper, we focus on designing distributed controllers for interconnected systems in situations where the controller sensing and actuation topology is inherited from that of the plant. The distributed systems considered are composed of discrete‐time linear time‐varying subsystems interconnected over arbitrary graph structures. The main contribution of this paper is to provide results on general graph interconnection structures in which the graphs have potentially an infinite number of vertices. This is accomplished by first extending previous machinery developed for systems with spatial dynamics on the lattice . We derive convex analysis and synthesis conditions for design in this setting. These conditions reduce to finite sequences of LMIs in the case of eventually periodic subsystems interconnected over finite graphs. The paper also provides results on distributed systems with communication latency and gives an illustrative example on the distributed control of hovercrafts along eventually periodic trajectories. The methodology developed here provides a unifying viewpoint for our previous and related work on distributed control. Copyright © 2013 John Wiley & Sons, Ltd.
Quantitative analysis and synthesis for networked control systems with non‐uniformly distributed packet dropouts and interval time‐varying sampling periods
Authors: Wang Yu‐Long , Han Qing‐Long
Published: October 2013

This paper is concerned with quantitative analysis and synthesis for a networked control system under simultaneous consideration of non‐uniformly distributed packet dropouts, interval time‐varying sampling periods and network‐induced delays. A new packet dropout separation method is proposed to separate packet dropouts from the lump sum of network‐induced delays and packet dropouts. An interval time‐varying sampling period approach, which is more general than a switched sampling period approach, is presented to model the variation of the sampling period. Then a packet dropout decomposition‐based Lyapunov functional is constructed to drive some stability criteria. Based on these stability criteria, a state feedback controller is designed to asymptotically stabilize the networked system in the sense of mean‐square. Numerical examples are given to illustrate the effectiveness of the obtained results. Copyright © 2013 John Wiley & Sons, Ltd.
The mycological effect on morphological, electrochemical and redox properties of the polyaniline surface
Authors: Binkauskiene Elena , Lugauskas Albinas , Bukauskas Virginijus
Published: October 2013

Biofilm formation with eight different microscopic fungi on the polyaniline surface and its effect on the morphological, electrochemical and redox properties have been studied. The investigations on selected Chrysosporium merdarium and Rhizomucor pusillus fungi behavior were performed. Conspicuous difference in the oxidation level, redox activity and oxalate impurities at the polymer surface layer treated with Chrysosporium merdarium and Rhizomucor pusillus was confirmed. The electrochemical behavior of the modified electrode was characterized using the cyclic voltammetry technique. The chemical composition of treated surface was determined by X‐ray photoelectron spectroscopy. For the estimation of conductive polymer morphology and roughness, the method of optical and scanning probe microscopy was applied, which showed that the polyaniline surfaces treated with Chrysosporium merdarium are homogenous and smoother than the polyaniline surfaces treated with Rhizomucor pusillus. Water contact angle measurements confirmed the effect of microbial growth on the properties of the polyaniline surface. Copyright © 2013 John Wiley & Sons, Ltd.
Cleaning requirements for silica‐coated sensors used in optical waveguide lightmode spectroscopy
Authors: Ryder Matthew P. , McGuire Joseph , Schilke Karl F.
Published: October 2013

Optical waveguide lightmode spectroscopy (OWLS), based on the incoupling of laser light into a waveguide sensor by an optical grating, allows for the in situ measurement of protein adsorption. Few reports have described cleaning methods for the surfaces of such sensors, and in this investigation, we compare common methods for cleaning of silica surfaces in relation to their effectiveness for cleaning silica‐coated waveguide sensors used in OWLS. For this purpose, atomic force microscopy (AFM) analysis of surface morphology and OWLS detection of protein adsorption kinetics were used to evaluate waveguide sensors before and after cleaning. While AFM line scans showed a substantial increase in average waveguide peak‐to‐valley height after RCA cleaning relative to all other methods tested, chemical etching owing to the alkaline component of the rolling circle amplification method rendered the waveguide unusable for detection of protein adsorption with OWLS. A revised method, based on replacement of the alkaline step with immersion in sodium dodecyl sulfate, was not only effective at cleaning OWLS waveguides off‐the‐shelf but also showed excellent protein adsorption reproducibility after ex situ cleaning. Moreover, the revised method showed excellent reproducibility when applied in situ, between repeated adsorption‐elution cycles. Copyright © 2013 John Wiley & Sons, Ltd.
Synthesis, characterization, and application of silver nanoparticle‐thiophenol nanocomposite film on the glassy carbon surface
Authors: Güzel Remziye , Ekşi Haslet , Üstündağ Zafer , Solak Ali Osman
Published: October 2013

In this study, 4‐thiophenol modified glassy carbon electrode was prepared by the reduction of 4‐diazothiophenol tetrafluoroborate salt. Silver nanoparticles were attached to the thiophenol modified surface to prepare a thiophenol‐silver nanoparticle composite film. 4‐Aminothiopenol molecules were deposited by self‐assembling technique to form multi‐layered nanofilms of TP/SNP/PhNH2 on glassy carbon substrate. These surfaces were characterized by cyclic voltammetry, electrochemical impedance spectroscopy, X‐ray photoelectron spectroscopy, reflectance‐absorption infrared spectroscopy, and ellipsometry at each multilayer film growth process. Atomic force microscopic images of GC/TP/SNP/PhNH2 surfaces were also acquired. The characterization methods show that the amine group containing surface permits the subsequent modification by a variety of coupling reactions for the immobilization of more complex systems. An application of the electrode modification for the determination of uric acid with a significantly lower detection limit is described. Copyright © 2013 John Wiley & Sons, Ltd.
Optimization of electrospun TiO2 nanofibers photoanode film for dye‐sensitized solar cells through interfacial pre‐treatment, controllable calcination, and surface post‐treatment
Authors: Du Pingfan , Song Lixin , Xiong Jie , Cui Can
Published: October 2013

Dye‐sensitized solar cells (DSSCs) are generally viewed as next generation photovoltaic devices. Electrospun TiO2 nanofibers (NFs) film can be used to construct photoanode for DSSCs. A systematic strategy to optimize such a novel photoanode material of DSSCs was elaborated in this paper. A main drawback of NFs photoanode is the poor adhesion of ceramic NFs film to its conductive glass substrate. This problem can be well solved by sandwiching a transition layer between the overlaid NFs film and the underlaid glass substrate through an interfacial spin‐coating pre‐treatment. After electrospinning, a controllable calcination is also indispensable for obtaining an ideal nanofibrous mat with good morphology and adhesion. The choice of calcination parameters including temperature, holding time, and heating rate was discussed in detail. In addition, a surface TiCl4 post‐treatment can further improve adhesion as well as strength for the NFs photoanode film. And the performance of the resulting DSSCs will benefit from the TiCl4 post‐treatment. Copyright © 2013 John Wiley & Sons, Ltd.
A Web-Based Survey of Erection Hardness Score and its Relationship to Aging, Sexual Behavior, Confidence, and Risk Factors in Japan
Authors: Kimura Masaki , Shimura Satoru , Tai Toshihiro , Kobayashi Hideyuki , Baba Shiro , Kano Munehide , Nagao Koichi
Published: October 2013

Introduction

Erection hardness is an elemental component of men's sexual quality of life that can be easily measured by the Erection Hardness Score (EHS). However, there are few published data regarding EHS, and there is little understanding of its relationships to aging, men's sexual behavior, sexual confidence, and risk factors in Japan.

Aim

To assess EHS and how it correlates to aging, sexual behaviors, sexual self-confidence, and risk factors in a Japanese population database.

Methods

A web-based cross-sectional nationwide survey conducted between March and May 2009 in Japan.

Main Outcome Measures

EHS, lifestyle factors, comorbidities, general health, sexual confidence, frequency of sexual behaviors, and attitudes toward treatment of erectile dysfunction (ED).

Results

A total of 7,710 men with a mean age of 39.3 ± 13.0 years participated in this survey. In 6,528 participants who were not using phosphodiesterase type 5 inhibitors, 3,540 (54.2%) had EHS ≤ 3 and 1,196 (18.3%) had EHS ≤ 2. We found a significant age-dependent decrease in EHS, sexual confidence, and frequency of sexual activities. Sexual confidence was strongly associated with higher EHS but was also associated with older age groups, presence of offspring, awareness of better general health, and greater frequency of sexual activity. In age-adjusted multivariate logistic regression, risk factors for a lower EHS (defined as EHS ≤ 2) were heavy smoking, which was defined as more than two packs per day (odds ratio [OR], 1.7) or a history of metabolic syndrome (OR, 1.4), hypertension (OR, 1.2), and diabetes mellitus (OR, 1.4).

Conclusions

EHS correlates to various elements, such as aging, sexual behaviors, sexual confidence, and ED-related risk factors, and can be a valuable tool in clinical practice for monitoring and treating ED and thereby improving the quality of life for men and their sexual partners.
Disadvantaged Family Background and Depression among Young Adults in the United States: The Roles of Chronic Stress and Self‐Esteem
Authors: Mossakowski Krysia N.
Published: October 2013

Although several longitudinal studies have demonstrated that having a disadvantaged family background is a risk factor for subsequent symptoms of depression, few studies have examined the mediating mechanisms that explain this long‐term relationship. Thus, this study uses US national longitudinal data and integrates social stress theory with the life course perspective by focusing on two mediating mechanisms—the chronic stress of poverty and self‐esteem during the transition to adulthood. Results reveal that self‐esteem largely mediates the inverse relationship between parental education and levels of depressive symptoms in young adulthood. However, the inverse relationship between parental occupational prestige and depressive symptoms among young adults is not mediated by self‐esteem, but rather long durations of poverty across 16 years. Overall, these findings suggest that different components of family socioeconomic status can leave a lasting imprint on mental health via the self‐concept and the chronic stress of poverty throughout the journey to adulthood. Copyright © 2013 John Wiley & Sons, Ltd.
Reaction Engineering Strategies for the Production of Inorganic Nanomaterials
Authors: Sebastian Victor , Arruebo Manuel , Santamaria Jesus
Published: October 2013

The rapid expansion of nanotechnology requires scaled‐up production rates to cope with increased nanomaterials demand. However, in many cases, the final uses of nanomaterials impose strict requisites on their physical and chemical characteristics including size, shape, chemical composition and type of functional groups on their surface. Frequently, additional features such as a limited degree of agglomeration are also demanded. These requisites represent a serious challenge to present‐day synthesis methods when nanomaterials must be produced in large amounts. Some of the possible solutions from the reaction engineering perspective are discussed in this work for both gas and liquid phase production processes. Special attention will be devoted to enabling technologies, which allow the production of engineered nanoparticles with limited aggregation and with a good control on their nano‐scale characteristics.
Macroscale Colloidal Noble Metal Nanocrystal Arrays and Their Refractive Index‐Based Sensing Characteristics
Authors: Shao Lei , Ruan Qifeng , Jiang Ruibin , Wang Jianfang
Published: October 2013

Colloidal noble metal nanocrystals are promising for a large number of optical and biotechnological applications. Many practical applications require the formation of large‐area, high‐density, and uniformly distributed metal nanocrystal arrays on various substrates, to overcome the limitations brought by the instability of colloidal metal nanocrystal solutions and the high cost of single‐particle spectroscopy characterizations. A method is developed for directly depositing colloidal metal nanocrystals, including Au nanospheres, Au nanorods, Au nanobipyramids, and (Au core)/(Ag shell) nanorods, from their solutions onto different substrates. The resultant nanocrystal arrays are relatively uniform and dense, with the peak extinction value of a single layer reaching 0.3. Their areas are up to 10 cm by 10 cm and can be further increased if larger‐size containers are utilized. The refractive index sensitivities are studied for Au nanorod arrays supported on glass slides, mesoporous silica and titania films, and capped with different molecules. Au nanorods deposited on mesoporous titania films are found to exhibit the highest index sensitivities, comparable to those of the same nanorod sample in solutions. It is expected that this approach will greatly facilitate plasmonic applications that require large‐area arrays of noble metal nanocrystals.
Methodological framework for the allocation of work packages in global software development
Authors: Ruano‐Mayoral Marcos , Casado‐Lumbreras Cristina , Garbarino‐Alberti Helena , Misra Sanjay
Published: October 2013

Global software development in software development industry is a new aspect for many software project managers. In this scenario, the allocation of work packages among project participants is not a simple task. This allocation was traditionally determined by availability and competence but this new trend introduces complexity in an already complex process. Given the need to define new models to guide managers in these operations, this paper presents a framework to allocate work packages among project participants. Apart from the introduction of the framework itself, the results of its implementation are presented. These results show a notable output of the implementation in terms of accuracy of task execution to planning, effect introduction and overall satisfaction. Copyright © 2013 John Wiley & Sons, Ltd.
A novel monitoring mechanism by event trigger for Hadoop system performance analysis
Authors: Liao Chih‐Shan , Chuang Chen‐Po , Chang Ruay‐Shiung
Published: October 2013

Cloud computing has become more and more popular nowadays since it possesses various conveniences such as pay as you go, dynamically deployment, and high efficiency. A numbers of cloud computing platforms are now in the market. Apache Hadoop, an open‐source platform, is one of these platforms which has been widely used by companies and organizations, because it is free for both research and production. From the perspective of service providers, it is better to see infrastructure running at the lowest possible power consumption and in the same time satisfying the QoS. From the viewpoint of the service clients, it is also the best situation that all functions they desire are running well at the lowest service cost. By putting ourselves in their shoes, in this paper, we propose the event trigger, which provides an automatic event recording mechanism. The event trigger applies the recorded parameters onto an easy‐understanding visual graph. By doing so, users will be able to adjust their deployment of hardware resource through a simple and straightforward understanding of their system performance records. Copyright © 2013 John Wiley & Sons, Ltd.
Mellow Yellow: Taking a Systems Thinking Approach to Designing Research on Transitioning to More Sustainable Sewage Management
Authors: Sankaran Shankar , Abeysuriya Kumi , Gray Janice , Kachenko Anthony
Published: October 2013

This paper will explain how a framework derived from systems thinking, including soft systems methodology and the use of action research as a methodology, shaped a research project addressing an area of application (sustainable sanitation). The research used F (intellectual framework) M (methodology for using F) to address A (area of application) for understanding rational intervention in human affairs proposed by Peter Checkland in the 1980s. This Australia‐first research project was conducted by a multidisciplinary team of collaborators from academia, industry and government that included researchers, practitioners and students. It explored the use of innovative urine‐diverting toilets in an institutional setting. The paper is focussed on the initial stages of the project—the project design and early investigative phase, and demonstrates how systems thinking and a transdisciplinary research approach were used to structure a complex problem related to sustainability, a problem that infringed on social and cultural issues. Copyright © 2013 John Wiley & Sons, Ltd.
CD44 Expressed on Cancer-Associated Fibroblasts Is a Functional Molecule Supporting the Stemness and Drug Resistance of Malignant Cancer Cells in the Tumor Microenvironment
Authors: Kinugasa Yumi , Matsui Takahiro , Takakura Nobuyuki
Published: October 2013

Cells constituting the tumor microenvironment are attractive targets for developing new cancer therapies. Here we show that cancer-associated fibroblasts (CAFs) support tumor growth in vivo and maintain the stemness of cancer stem/initiating cells in an in vitro model using an established CAF cell line. We found that CD44 is abundantly expressed on CAFs. This molecule is a cancer stem cell marker in several tumors, but its role in tumorigenesis when expressed by CAFs has not been investigated. It is generally accepted that hypoxic and hyponutritional conditions are triggers of cancer malignancy. We found that CAFs strongly express CD44 in hypoxic and avascular areas in the tumor and that its expression on established CAFs is upregulated under hypoxic and hyponutritional conditions in vitro. In addition, CAF CD44-positivity in tumor tissues was increased after treatment with inhibitors of angiogenesis. Using cocultures and tumor sphere formation assays, CAFs from wild-type mice were found to sustain the stemness of cancer stem/initiating cells, while CD44-deficient CAFs did not. Furthermore, CD44 was involved in malignant cancer cell drug resistance mechanisms. In conclusion, our study suggests that CD44 on CAFs is a functional molecule contributing to the maintenance of cancer stem cell populations in the tumor microenvironment. Stem Cells  2014;32:145–156
Critical Components of the Pluripotency Network Are Targets for the p300/CBP Interacting Protein (p/CIP) in Embryonic Stem Cells
Authors: Chitilian J.M. , Thillainadesan G. , Manias J.L. , Chang W.Y. , Walker E. , Isovic M. , Stanford W.L. , Torchia J.
Published: October 2013

p/CIP, also known as steroid receptor coactivator 3 (SRC-3)/Nuclear Receptor Coactivator 3 (NCoA3), is a transcriptional coactivator that binds liganded nuclear hormone receptors, as well as other transcription factors, and facilitates transcription through direct recruitment of accessory factors. We have found that p/CIP is highly expressed in undifferentiated mouse embryonic stem cells (mESCs) and is downregulated during differentiation. siRNA-mediated knockdown of p/CIP decreased transcript levels of Nanog, but not Oct4 or Sox2. Microarray expression analysis showed that Klf4, Tbx3, and Dax-1 are significantly downregulated in mESCs when p/CIP is knocked down. Subsequent chromatin immunoprecipitation (ChIP) analysis demonstrated that Tbx3, Klf4, and Dax-1 are direct transcriptional targets of p/CIP. Using the piggyBac transposition system, a mouse ESC line that expresses Flag-p/CIP in a doxycycline-dependent manner was generated. p/CIP overexpression increased the level of target genes and promoted the formation of undifferentiated colonies. Collectively, these results indicate that p/CIP contributes to the maintenance of ESC pluripotency through direct regulation of essential pluripotency genes. To better understand the mechanism by which p/CIP functions in ESC pluripotency, we integrated our ChIP and transcriptome data with published protein-protein interaction and promoter occupancy data to draft a p/CIP gene regulatory network. The p/CIP gene regulatory network identifies various feed-forward modules including one in which p/CIP activates members of the extended pluripotency network, demonstrating that p/CIP is a component of this extended network. Stem Cells  2014;32:204–215