bluuebunny/crossref_metadata_2025 huggingface dataset:
N,N′-Bis((6-methoxylpyridin-2-yl)methylene)-p-phenylenediimine based d10 transition metal complexes and their utilization in co-sensitized solar cells
Authors: Wei Liguo , Yang Yulin , Fan Ruiqing , Na Yong , Wang Ping , Dong Yuwei , Yang Bin , Cao Wenwu
Published: May 2014

New d10 transition metal complexes of ZnL, CdL and HgL enhanced the performance of DSSCs by co-sensitization with N719.
Towards full-color-tunable emission of two component Eu(iii)-doped Gd(iii) coordination frameworks by the variation of excitation light
Authors: Zhang Fengming , Yan Pengfei , Li Hongfeng , Zou Xiaoyan , Hou Guangfeng , Li Guangming
Published: May 2014

Eu(iii)-doped Gd(iii) pyrazine-2,3,5,6-tetracarboxylate alkali–lanthanide metal–organic frameworks (LnMOF) with a unique (411·68·82)(43·62·8)(43) topology present full color-tunable luminescence and white emission by the variation of excitation wavelengths.
Novel Li2MnO3 nanowire anode with internal Li-enrichment for use in a Li-ion battery
Authors: Wang Dandan , Zhao Yunlong , Xu Xu , Hercule Kalele Mulonda , Yan Mengyu , An Qinyou , Tian Xiaocong , Xu Jiaming , Qu Longbing , Mai Liqiang
Published: May 2014

We obtained a novel Li2MnO3 nanowire anode with internal Li-enrichment for use in Li-ion batteries.
Hierarchical MnCo2O4nanosheet arrays/carbon cloths as integrated anodes for lithium-ion batteries with improved performance
Authors: Hou Xiaojuan , Wang Xianfu , Liu Bin , Wang Qiufan , Luo Tao , Chen Di , Shen Guozhen
Published: May 2014

3D hierarchical MnCo2O4nanosheet arrays were synthesizedviaa hydrothermal method on carbon cloths, acting as binder-free anodes for lithium-ion batteries with better performance than their Co3O4counterparts.
Molecular photo-thermal optical coherence phase microscopy using gold nanorods
Authors: Pai Jing-Hong , Liu Tianqing , Hsu Hung-Yao , Wedding A. Bruce , Thierry Benjamin , Bagnaninchi Pierre O.
Published: May 2014

A new evolution of OCT is termed molecular OCPM, which is capable of imaging the expression of molecular markers at the cellular level by using functionalized gold nanorods as imaging agents.
A multivariate insight into ionic liquids toxicities
Authors: Paternò Alessio , D'Anna Francesca , Musumarra Giuseppe , Noto Renato , Scirè Salvatore
Published: May 2014

A multivariate insight into the toxicities of ionic liquids provides a comprehensive picture and guidelines for the evaluation of their eco- and bio-sustainability.
CVD graphene based immunosensor
Authors: Loo Adeline Huiling , Ambrosi Adriano , Bonanni Alessandra , Pumera Martin
Published: May 2014

Herein, we aim to draw attention to employing chemical vapour deposition (CVD) method grown graphene as a potential platform for immunosensing of IgG.
Cobaltate anion couples terminal dienes with trifluoroacetic anhydride: a direct fluoroacylation of 1,3-dienes
Authors: Kohn Benjamin L. , Rovis Tomislav
Published: May 2014

Perfluoroketones are useful products and intermediates in medicinal and materials chemistry.
Colloidal membranes of hard rods: unified theory of free edge structure and twist walls
Authors: Kaplan C. Nadir , Meyer Robert B.
Published: May 2014

The unified framework of the monolayer edge and twist walls, observed in colloidal fluid membranes, reveals their structure and stability.
Fabrication of homogenous three dimensionally ordered conducting polymer–polystyrene opal structures in microfluidic channels
Authors: Gorey Brian , Smyth Malcolm R. , White Blánaid , Morrin Aoife
Published: May 2014

A chemical polymerisation method for fabricating an electrochemically addressable, three dimensionally (3-D) ordered homogenous polyaniline (PANI)-based opal structure in a microfluidic channel is described.
Nucleocytoplasmic shuttling: a common theme in mechanotransduction
Authors: Sharili Amir S. , Connelly John T.
Published: May 2014

Cells sense their mechanical and physical environment through diverse mechanisms, and these interactions specify a wide range of responses including growth, survival, migration and differentiation. Although much work has focused on dissecting the adhesive and structural components of the cell responsible for transducing external mechanical forces into biochemical signalling cascades, only recently have studies begun to examine how mechanical signals are transmitted to the nucleus and activate specific gene expression programmes. One necessary step in these processes is the transport of signalling molecules from the cytoplasm to the nucleus. The SRF (serum-response factor) and YAP (Yes-associated protein)/TAZ (transcriptional co-activator with PDZ-binding motif) pathways are known mediators of this process in multiple cell types, including mesenchymal stem cells, keratinocytes, mammary epithelial cells and smooth muscle cells. In addition, recent evidence suggests a potential role for β-catenin and Smad signalling in mechanotransduction, but further mechanistic studies are needed to prove this hypothesis. As a model system, the epidermis of the skin is one tissue in which nucleocytoplasmic shuttling mediates cellular mechanosensing and is essential for tissue development, homoeostasis and repair. We propose that nuclear translocation is a common element of mechanotransduction conserved across multiple cell types and tissues.
In vivo cell reprogramming to pluripotency: exploring a novel tool for cell replenishment and tissue regeneration
Authors: de Lázaro Irene , Kostarelos Kostas
Published: May 2014

The potential of cell-replacement strategies for the treatment of disorders in which a particular cell type is damaged or degenerated has prompted the search for the perfect cell source. iPSCs (induced pluripotent stem cells) stand out as very advantageous candidates thanks to their self-renewal capacity and differentiation potential, together with the possibility of generating them from autologous somatic cells with minimally invasive techniques. However, their differentiation into the required cell type, precise delivery and successful engraftment and survival in the host are still challenging. We have proposed the transient reprogramming of somatic cells towards a pluripotent state in their in vivo microenvironment as a means to facilitate the regeneration of the tissue. The initial reports of in vivo reprogramming to pluripotency in the literature are reviewed and the potential clinical applications of this strategy are discussed.
The intestinal stem cell niche: a computational tissue approach
Authors: Buske Peter , Przybilla Jens , Loeffler Markus , Galle Joerg
Published: May 2014

The intestinal epithelium is permanently renewed during homoeostasis. Stable function of its stem cells is ensured by interaction with a specific tissue compartment, the so-called ‘intestinal stem cell niche’. The essential regulatory principles of this niche are still under debate. In order to approach this question, we have introduced several single cell-based models of the spatiotemporal stem cell organization in murine intestinal crypts and organoids. In the present article, we provide a brief review of these models. Starting with pedigree models reproducing cell kinetics, over the last few years, we have successively improved these models by refining the biomechanical representation of the system and introducing environmentally controlled lineage specification. Our current models of the intestinal crypt are capable of linking a broad spectrum of experimental observations encompassing spatially confined cell proliferation, directed cell migration, multiple cell lineage decisions and clonal competition. Our model of intestinal organoids provides for the first time a description of a self-organizing intestinal stem cell niche. It suggests that this niche is established by secretory activity of specified cells and in addition requires a defined spatial organization, which sensitively depends on tissue biomechanics.
New insights into skin stem cell aging and cancer
Authors: Ortells M. Carmen , Keyes William M.
Published: May 2014

Adult tissue homoeostasis requires continual replacement of cells that are lost due to normal turnover, injury and disease. However, aging is associated with an overall decline in tissue function and homoeostasis, suggesting that the normal regulatory processes that govern self-renewal and regeneration may become impaired with age. Tissue-specific SCs (stem cells) lie at the apex of organismal conservation and regeneration, ultimately being responsible for continued tissue maintenance. In many tissues, there are changes in SC numbers, or alteration of their growth properties during aging, often involving imbalances in tumour-suppressor- and oncogene-mediated pathways. Uncovering the molecular mechanisms leading to changes in SC function during aging will provide an essential tool to address tissue-specific age-related pathologies. In the present review, we summarize the age-related alterations found in different tissue SC populations, highlighting recently identified changes in aged HFSCs (hair-follicle SCs) in the skin.
Tadpole tail regeneration in Xenopus
Authors: Chen Yaoyao , Love Nick R. , Amaya Enrique
Published: May 2014

Some organisms have a remarkable ability to heal wounds without scars and to regenerate complex tissues following injury. By gaining a more complete understanding of the biological mechanisms that promote scar-free healing and tissue regeneration, it is hoped that novel treatments that can enhance the healing and regenerative capacity of human patients can be found. In the present article, we briefly examine the genetic, molecular and cellular mechanisms underlying the regeneration of the Xenopus tadpole tail.
Engineering tissue for the fetus: stem cells and matrix signalling
Authors: De Coppi Paolo
Published: May 2014

Congenital malformations are major causes of disease and death during the first years of life and, most of the time, functional replacement of the missing or damaged organs remains an unmet clinical need. Particularly relevant for the treatment of congenital malformation would be to collect the stem cells at diagnosis, before birth, to be able to intervene during the gestation or in the neonatal period. Human AFSCs (amniotic fluid stem cells), which have characteristics intermediate between those of embryonic and adult stem cells, have been isolated. c-Kit+Lin− cells derived from amniotic fluid display a multilineage haemopoietic potential and they can be easily reprogrammed to a pluripotent status. Although, in the future, we hope to use cells derived from the amniotic fluid, we and others have proved recently that simple organs such as the trachea can be engineered using adult progenitors utilizing decellularized cadaveric matrices. A similar approach could be used in the future for more complex organs such as the muscles, intestines or lungs.
Coupled cellular therapy and magnetic targeting for airway regeneration
Authors: Ordidge Katherine L. , Gregori Maria , Kalber Tammy L. , Lythgoe Mark F. , Janes Sam M. , Giangreco Adam
Published: May 2014

Airway diseases including COPD (chronic obstructive pulmonary disease), cystic fibrosis and lung cancer are leading causes of worldwide morbidity and mortality, with annual healthcare costs of billions of pounds. True regeneration of damaged airways offers the possibility of restoring lung function and protecting against airway transformation. Recently, advances in tissue engineering have allowed the development of cadaveric and biosynthetic airway grafts. Although these have produced encouraging results, the ability to achieve long-term functional airway regeneration remains a major challenge. To promote regeneration, exogenously delivered stem and progenitor cells are being trialled as cellular therapies. Unfortunately, current evidence suggests that only small numbers of exogenously delivered stem cells engraft within lungs, thereby limiting their utility for airway repair. In other organ systems, magnetic targeting has shown promise for improving long-term robust cell engraftment. This technique involves in vitro cell expansion, magnetic actuation and magnetically guided cell engraftment to sites of tissue damage. In the present paper, we discuss the utility of coupling stem cell-mediated cellular therapy with magnetic targeting for improving airway regeneration.
Study of Takagi‐Sugeno fuzzy‐based terminal‐sliding mode fault‐tolerant control
Authors: Xu Sendren Sheng‐Dong , Liu Yi‐Kuo
Published: May 2014

This study studies the fault‐tolerant control (FTC) design based on the Takagi‐Sugeno (T‐S) fuzzy system models and terminal‐sliding‐mode control (TSMC). This hybrid scheme can keep the advantages of both methods. By using the T‐S fuzzy models to approximate the original non‐linear system, the online computation burden can be alleviated since most of the T‐S parameters can be offline computed. Moreover, TSMC not only owns the merits, including robustness to uncertainties and/or disturbances, fast response and easy implementation, but also performs better than conventional sliding‐mode control (SMC) since the system states of TSMC will converge in finite time to the control objective point, that is, equivalent point, after the system states intersect sliding surface. Both of the active and passive FTC design schemes are presented. The proposed analytical results are also applied to the FTC for the attitude stabilisation of a spacecraft. Simulation results demonstrate the benefits of the proposed scheme.
Estimation and rejection of aperiodic disturbance in a modified repetitive‐control system
Authors: Zhou Lan , She Jinhua , Wu Min , He Yong , Zhou Shaowu
Published: May 2014

This study concerns the problem of aperiodic‐disturbance estimation and rejection in a modified repetitive‐control system (MRCS). First, the configuration of an improved MRCS with an equivalent‐input‐disturbance (EID) estimator is constructed. The aperiodic disturbances are estimated by the EID estimator and their effect to the output channel are compensated by directly incorporating the estimates into the repetitive‐control law. Next, the small gain theory and the separation theorem are used to derive the stability criterion. Then, the two‐dimensional system approach and pole assignment are employed to constitute two independent design algorithms, one for the design of the state‐feedback gains of the MRCS and one for the design of the EID estimator. Finally, a numerical example demonstrates the validity of the method.
Effective background modelling and subtraction approach for moving object detection
Authors: Liu Wei , Yu Hongfei , Yuan Huai , Zhao Hong , Xu Xiaowei
Published: May 2014

This study presents a hierarchical background modelling and subtraction approach for real‐time detection of moving objects. At the first level, a novel pixel‐wise background modelling method is proposed for coarse detection. The method can dynamically assign the optimal number of components for each pixel with the borrow–lend strategy. And a flexible learning rate which is variable and different for each component is presented to adapt to scene changes. Additionally, a new mechanism using a framework of finite state machine is introduced to maintain and update the background models. At the second level, in order to deal with sudden illumination changes, a block‐wise foreground validation approach is adopted for refined detection. The authors compare the proposed approach with state‐of‐the‐art methods and experimental results under various scenes demonstrate the robustness and effectiveness of the proposed approach.
Parallel Monte Carlo approach for distribution reliability assessment
Authors: Martinez‐Velasco Juan A. , Guerra Gerardo
Published: May 2014

This study presents the basic features of a Monte Carlo approach for reliability evaluation of distribution systems without embedded generation using parallel computation. The test system is represented by means of a three‐phase model that includes protective devices and is simulated during one year. The procedure has been implemented in an open environment in which OpenDSS is driven from MATLAB. The document includes a detailed description of the procedure, and some results derived from the simulation of an overhead distribution test system.
Using graphical adaptive lasso approach to construct transcription factor and microRNA's combinatorial regulatory network in breast cancer
Authors: Su Naifang , Dai Ding , Deng Chao , Qian Minping , Deng Minghua
Published: May 2014

Discovering the regulation of cancer‐related gene is of great importance in cancer biology. Transcription factors and microRNAs are two kinds of crucial regulators in gene expression, and they compose a combinatorial regulatory network with their target genes. Revealing the structure of this network could improve the authors’ understanding of gene regulation, and further explore the molecular pathway in cancer. In this article, the authors propose a novel approach graphical adaptive lasso (GALASSO) to construct the regulatory network in breast cancer. GALASSO use a Gaussian graphical model with adaptive lasso penalties to integrate the sequence information as well as gene expression profiles. The simulation study and the experimental profiles verify the accuracy of the authors’ approach. The authors further reveal the structure of the regulatory network, and explore the role of feedforward loops in gene regulation. In addition, the authors discuss the combinatorial regulatory effect between transcription factors and microRNAs, and select miR‐155 for detailed analysis of microRNA's role in cancer. The proposed GALASSO approach is an efficient method to construct the combinatorial regulatory network. It also provides a new way to integrate different data sources and could find more applications in meta‐analysis problem.
Method of nanocarbon/montmorillonite powder extraction
Authors: Tang Jialun , Zhang Zepeng , Zhou Daojin
Published: May 2014

In this reported work, carbon/montmorillonite (C/MMT) nanometre particles and micrometre particles blended were extracted by the froth flotation method, extraction and density gradient centrifugation. X‐ray diffraction, scanning electron microscopy, transmission electron microscopy and particle size analysis were employed to characterise the C/MMT extracted before and after. The results have shown that the froth flotation method cannot effectively collect C/MMT nanocomposites, and the extraction is not effective, whereas density gradient centrifugation can collect vari‐size grained C/MMT nanocomposite particles. On using density gradient centrifugation, the thicknesses of C/MMT nanocomposite particles are <20 nm.
Two-dimensional fluorescence-detected coherent spectroscopy with absolute phasing by confocal imaging of a dynamic grating and 27-step phase-cycling
Authors: De Arijit K. , Monahan Daniele , Dawlaty Jahan M. , Fleming Graham R.
Published: May 2014

We present a novel experimental scheme for two-dimensional fluorescence-detected coherent spectroscopy (2D-FDCS) using a non-collinear beam geometry with the aid of “confocal imaging” of dynamic (population) grating and 27-step phase-cycling to extract the signal. This arrangement obviates the need for distinct experimental designs for previously developed transmission detected non-collinear two-dimensional coherent spectroscopy (2D-CS) and collinear 2D-FDCS. We also describe a novel method for absolute phasing of the 2D spectrum. We apply this method to record 2D spectra of a fluorescent dye in solution at room temperature and observe “spectral diffusion.”
Elastically cooperative activated barrier hopping theory of relaxation in viscous fluids. II. Thermal liquids
Authors: Mirigian Stephen , Schweizer Kenneth S.
Published: May 2014

Building on the elastically collective nonlinear Langevin equation theory developed for hard spheres in Paper I, we propose and implement a quasi-universal theory for the alpha relaxation of thermal liquids based on mapping them to an effective hard sphere fluid via the dimensionless compressibility. The result is a zero adjustable parameter theory that can quantitatively address in a unified manner the alpha relaxation time over 14 or more decades. The theory has no singularities above zero Kelvin, and relaxation in the equilibrium low temperature limit is predicted to be of a roughly Arrhenius form. The two-barrier (local cage and long range collective elastic) description results in a rich dynamic behavior including apparent Arrhenius, narrow crossover, and deeply supercooled regimes, and multiple characteristic or crossover times and temperatures of clear physical meaning. Application of the theory to nonpolar molecules, alcohols, rare gases, and liquids metals is carried out. Overall, the agreement with experiment is quite good for the temperature dependence of the alpha time, plateau shear modulus, and Boson-like peak frequency for van der Waals liquids, though less so for hydrogen-bonding molecules. The theory predicts multiple growing length scales upon cooling, which reflect distinct aspects of the coupled local hopping and cooperative elastic physics. Calculations of the growth with cooling of an activation volume, which is strongly correlated with a measure of dynamic cooperativity, agree quantitatively with experiment. Comparisons with elastic, entropy crisis, dynamic facilitation, and other approaches are performed, and a fundamental basis for empirically extracted crossover temperatures is established. The present work sets the stage for addressing distinctive glassy phenomena in polymer melts, and diverse liquids under strong confinement.
The Nosé–Hoover looped chain thermostat for low temperature thawed Gaussian wave-packet dynamics
Authors: Coughtrie David J. , Tew David P.
Published: May 2014

We have used a generalised coherent state resolution of the identity to map the quantum canonical statistical average for a general system onto a phase-space average over the centre and width parameters of a thawed Gaussian wave packet. We also propose an artificial phase-space density that has the same behaviour as the canonical phase-space density in the low-temperature limit, and have constructed a novel Nosé–Hoover looped chain thermostat that generates this density in conjunction with variational thawed Gaussian wave-packet dynamics. This forms a new platform for evaluating statistical properties of quantum condensed-phase systems that has an explicit connection to the time-dependent Schrödinger equation, whilst retaining many of the appealing features of path-integral molecular dynamics.
Dissociation pathways of a single dimethyl disulfide on Cu(111): Reaction induced by simultaneous excitation of two vibrational modes
Authors: Motobayashi Kenta , Kim Yousoo , Arafune Ryuichi , Ohara Michiaki , Ueba Hiromu , Kawai Maki
Published: May 2014

We present a novel reaction mechanism for a single adsorbed molecule that proceeds via simultaneous excitation of two different vibrational modes excited by inelastic tunneling electrons from a scanning tunneling microscope. Specifically, we analyze the dissociation of a single dimethyl disulfide (DMDS, (CH3S)2) molecule on Cu(111) by using a versatile theoretical method, which permits us to simulate reaction rates as a function of sample bias voltage. The reaction is induced by the excitation of C-H stretch and S-S stretch modes by a two-electron process at low positive bias voltages. However, at increased voltages, the dissociation becomes a single-electron process that excites a combination mode of these stretches, where excitation of the C-H stretch is the energy source and excitation of the S-S stretch mode enhances the anharmonic coupling rate. A much smaller dissociation yield (few orders of magnitude) at negative bias voltages is understood in terms of the projected density of states of a single DMDS on Cu(111), which reflects resonant excitation through the molecular orbitals.
MONSTIR II: A 32-channel, multispectral, time-resolved optical tomography system for neonatal brain imaging
Authors: Cooper Robert J. , Magee Elliott , Everdell Nick , Magazov Salavat , Varela Marta , Airantzis Dimitrios , Gibson Adam P. , Hebden Jeremy C.
Published: May 2014

We detail the design, construction and performance of the second generation UCL time-resolved optical tomography system, known as MONSTIR II. Intended primarily for the study of the newborn brain, the system employs 32 source fibres that sequentially transmit picosecond pulses of light at any four wavelengths between 650 and 900 nm. The 32 detector channels each contain an independent photo-multiplier tube and temporally correlated photon-counting electronics that allow the photon transit time between each source and each detector position to be measured with high temporal resolution. The system's response time, temporal stability, cross-talk, and spectral characteristics are reported. The efficacy of MONSTIR II is demonstrated by performing multi-spectral imaging of a simple phantom.
Dynamic symmetry of indirectly driven inertial confinement fusion capsules on the National Ignition Facility
Authors: Town R. P. J. , Bradley D. K. , Kritcher A. , Jones O. S. , Rygg J. R. , Tommasini R. , Barrios M. , Benedetti L. R. , Berzak Hopkins L. F. , Celliers P. M. , Döppner T. , Dewald E. L. , Eder D. C. , Field J. E. , Glenn S. M. , Izumi N. , Haan S. W. , Khan S. F. , Kline J. L. , Kyrala G. A. , Ma T. , Milovich J. L. , Moody J. D. , Nagel S. R. , Pak A. , Peterson J. L. , Robey H. F. , Ross J. S. , Scott R. H. H. , Spears B. K. , Edwards M. J. , Kilkenny J. D. , Landen O. L.
Published: May 2014

In order to achieve ignition using inertial confinement fusion it is important to control the growth of low-mode asymmetries as the capsule is compressed. Understanding the time-dependent evolution of the shape of the hot spot and surrounding fuel layer is crucial to optimizing implosion performance. A design and experimental campaign to examine sources of asymmetry and to quantify symmetry throughout the implosion has been developed and executed on the National Ignition Facility (NIF) [E. I. Moses et al., Phys. Plasmas 16, 041006 (2009)]. We have constructed a large simulation database of asymmetries applied during different time intervals. Analysis of the database has shown the need to measure and control the hot-spot shape, areal density distribution, and symmetry swings during the implosion. The shape of the hot spot during final stagnation is measured using time-resolved imaging of the self-emission, and information on the shape of the fuel at stagnation can be obtained from Compton radiography [R. Tommasini et al., Phys. Plasmas 18, 056309 (2011)]. For the first time on NIF, two-dimensional inflight radiographs of gas-filled and cryogenic fuel layered capsules have been measured to infer the symmetry of the radiation drive on the capsule. These results have been used to modify the hohlraum geometry and the wavelength tuning to improve the inflight implosion symmetry. We have also expanded our shock timing capabilities by the addition of extra mirrors inside the re-entrant cone to allow the simultaneous measurement of shock symmetry in three locations on a single shot, providing asymmetry information up to Legendre mode 4. By diagnosing the shape at nearly every step of the implosion, we estimate that shape has typically reduced fusion yield by about 50% in ignition experiments.
Efficient zinc sulfide cathode layers for organic photovoltaic applications via n-type doping
Authors: Traverse Christopher J. , Young Margaret , Wagner Sean , Zhang Pengpeng , Askeland Per , Barr Miles C. , Lunt Richard R.
Published: May 2014

We demonstrate efficient zinc sulfide cathode window layers in thin-film organic photovoltaics enabled by n-type doping zinc sulfide (ZnS) with aluminum sulfide (Al2S3) directly through co-deposition. By optimizing the Al2S3 concentration, the power conversion efficiency is improved from 0.6% ± 0.2% in undoped ZnS window layer devices to 1.8% ± 0.1%, identical to control devices. The mechanism for this performance enhancement is shown to stem from the enhanced conductivity and interface energetics of ZnS upon n-type doping. This work expands the catalog of efficient, inorganic, non-toxic, cathode side window layers that could be effective in a range of thin-film photovoltaic technologies.
Signature of cluster disruption within magnetic fluid samples: The key information provided by low frequency alternating current susceptibility measurements
Authors: Du Zhongzhou , Liu Wenzhong , Zhong Jing , Zhou Ming , Zhang Pu , Cesar Morais Paulo
Published: May 2014

This paper is focused on the signature of thermal-assisted cluster disruption while analyzing the inverse alternating current (AC) susceptibility (1/χ) versus temperature (T) curves recorded at lower AC frequencies (f), below 300 Hz. A commercial oil-based magnetic fluid (MF) sample was used in the experiments to investigate the critical temperature (T*) that characterizes the thermal disruption of aggregates suspended within the MF sample. T* was found to reduce as f increased within the frequency range of our investigation (63–263 Hz). Furthermore, T* was found to scale with the square of the applied AC frequency. Both theoretical and experimental evidences support that the excitation field frequency (f) dependence of the critical temperature (T*) is well described by T*(f)=T*(0)−Af21+Bf2. The model is based on energy absorption of magnetic nanoparticles in an AC magnetic field.
Novel attributes in modeling and optimizing of the new graphene based InxGa1−xN Schottky barrier solar cells
Authors: Arefinia Zahra , Asgari Asghar
Published: May 2014

Based on the ability of InxGa1−xN materials to optimally span the solar spectrum and their superior radiation resistance, solar cells based on p-type InxGa1−xN with low indium contents and interfacing with graphene film (G/InxGa1−xN), is proposed to exploit the benefit of transparency and work function tunability of graphene. Then, their solar power conversion efficiency modeled and optimized using a new analytical approach taking into account all recombination processes and accurate carrier mobility. Furthermore, their performance was compared with graphene on silicon counterparts and G/p-InxGa1−xN showed relatively smaller short-circuits current (∼7 mA/cm2) and significantly higher open-circuit voltage (∼4 V) and efficiency (∼30%). The thickness, doping concentration, and indium contents of p-InxGa1−xN and graphene work function were found to substantially affect the performance of G/p-InxGa1−xN.
Influence of grain size and surface condition on minority-carrier lifetime in undoped n-BaSi2 on Si(111)
Authors: Takabe Ryota , Hara Kosuke O. , Baba Masakazu , Du Weijie , Shimada Naoya , Toko Kaoru , Usami Noritaka , Suemasu Takashi
Published: May 2014

We have fabricated approximately 0.5-μm-thick undoped n-BaSi2 epitaxial films with various average grain areas ranging from 2.6 to 23.3 μm2 on Si(111) by molecular beam epitaxy, and investigated their minority-carrier lifetime properties by the microwave-detected photoconductivity decay method at room temperature. The measured excess-carrier decay curves were divided into three parts in terms of decay rate. We characterized the BaSi2 films using the decay time of the second decay mode, τSRH, caused by Shockley-Read-Hall recombination without the carrier trapping effect, as a measure of the minority-carrier properties in the BaSi2 films. The measured τSRH was grouped into two, independently of the average grain area of BaSi2. BaSi2 films with cloudy surfaces or capped intentionally with a 3 nm Ba or Si layer, showed large τSRH (ca. 8 μs), whereas those with mirror surfaces much smaller τSRH (ca. 0.4 μs). X-ray photoelectron spectroscopy measurements were performed to discuss the surface region of the BaSi2 films.
The differential Howland current source with high signal to noise ratio for bioimpedance measurement system
Authors: Liu Jinzhen , Qiao Xiaoyan , Wang Mengjun , Zhang Weibo , Li Gang , Lin Ling
Published: May 2014

The stability and signal to noise ratio (SNR) of the current source circuit are the important factors contributing to enhance the accuracy and sensitivity in bioimpedance measurement system. In this paper we propose a new differential Howland topology current source and evaluate its output characters by simulation and actual measurement. The results include (1) the output current and impedance in high frequencies are stabilized after compensation methods. And the stability of output current in the differential current source circuit (DCSC) is 0.2%. (2) The output impedance of two current circuits below the frequency of 200 KHz is above 1 MΩ, and below 1 MHz the output impedance can arrive to 200 KΩ. Then in total the output impedance of the DCSC is higher than that of the Howland current source circuit (HCSC). (3) The SNR of the DCSC are 85.64 dB and 65 dB in the simulation and actual measurement with 10 KHz, which illustrates that the DCSC effectively eliminates the common mode interference. (4) The maximum load in the DCSC is twice as much as that of the HCSC. Lastly a two-dimensional phantom electrical impedance tomography is well reconstructed with the proposed HCSC. Therefore, the measured performance shows that the DCSC can significantly improve the output impedance, the stability, the maximum load, and the SNR of the measurement system.
Note: Proton irradiation at kilowatt-power and neutron production from a free-surface liquid-lithium target
Authors: Halfon S. , Arenshtam A. , Kijel D. , Paul M. , Weissman L. , Aviv O. , Berkovits D. , Dudovitch O. , Eisen Y. , Eliyahu I. , Feinberg G. , Haquin G. , Hazenshprung N. , Kreisel A. , Mardor I. , Shimel G. , Shor A. , Silverman I. , Tessler M. , Yungrais Z.
Published: May 2014

The free-surface Liquid-Lithium Target, recently developed at Soreq Applied Research Accelerator Facility (SARAF), was successfully used with a 1.9 MeV, 1.2 mA (2.3 kW) continuous-wave proton beam. Neutrons (∼2 × 1010 n/s having a peak energy of ∼27 keV) from the 7Li(p,n)7Be reaction were detected with a fission-chamber detector and by gold activation targets positioned in the forward direction. The setup is being used for nuclear astrophysics experiments to study neutron-induced reactions at stellar energies and to demonstrate the feasibility of accelerator-based boron neutron capture therapy.
An exact field solution of contact resistance and comparison with the transmission line model
Authors: Zhang Peng , Lau Y. Y.
Published: May 2014

Based on the exact solution of the electric field, the contact resistance is calculated and compared with the widely used lumped-circuit transmission line model. Our model fully accounts for the spreading resistance, and is applicable to arbitrary contact size, film thickness, and resistivity in different parts forming the contact. The regimes dominated by the specific contact resistance or by the spreading resistance are identified and compared with experimental data.
Large thickness airfoils with high lift in the operating range of angle of attack
Authors: Li Xingxing , Yang Ke , Zhang Lei , Bai Jingyan , Xu Jianzhong
Published: May 2014

This paper presents the design, prediction and evaluation of a family of large thickness airfoils with blunt trailing edges. The family includes four airfoils, whose relative thickness ranges from 45% to 60% and relative thickness of trailing edge ranges from 7% to 16%. These airfoils are designed by the RFOIL solver at different design Reynolds numbers of 4.0 × 106, 3.5 × 106, 3.0 × 106, and 2.5 × 106 with increasing thickness. The design Reynolds numbers are calculated by the operating characteristics of a 5 MW wind turbine. The design objectives focus on the aerodynamic performance in operating ranges of angle of attack at blade root, differing from those of the aviation airfoils and traditional wind turbine airfoils. And the main design constraint is the stability of the lift coefficients in range of large angles of attack with the variation of Reynolds number. The predictions by RFOIL show that, in the range of angle of attack (15°–30°), the values of lift coefficient of the four new airfoils are largely in the range of (1.0–1.7) and stable with the variation of Reynolds number. These features help obtain more efficient and stable output. The evaluation results indicate that the overall performance of new airfoils is acceptable for the design of multi-MW rotor blades.
Parallel parametric amplification of coherently excited propagating spin waves in a microscopic Ni81Fe19 waveguide
Authors: Brächer T. , Pirro P. , Meyer T. , Heussner F. , Lägel B. , Serga A. A. , Hillebrands B.
Published: May 2014

We present parallel parametric amplification of coherently excited, propagating spin waves in a microstructured magnonic Ni81Fe19 waveguide. Amplification is achieved by the pumping field generated by a microwave current flowing through a Cu micro-stripline underneath the waveguide. By employing microfocussed Brillouin light scattering spectroscopy, we investigate the spatial decay of the propagating spin waves and their amplification by means of parallel pumping. We analyze the dependence of the intensity of the amplified spin waves on the spin-wave excitation power, pumping power, and pumping duration, revealing the most efficient working point for a noise-free amplification. This paves the way for a frequency selective amplification of spin waves in microstructured magnonic circuits.
Flow-through electroporation of mammalian cells in decoupled flow streams using microcapillaries
Authors: Luo Yuan , Yobas Levent
Published: May 2014

We report on reversible electroporation of cells in a flow-through microfluidic device, whereby the required electric field is delivered through a set of integrated microcapillaries between a centre stream of cells and side streams of liquid electrolytes. The electrolytes are applied with a sine wave voltage and cells flow by the microcapillary openings encounter a burst of ac field with a duration and strength determined by their average speed and spatial proximity to the microcapillary openings, respectively. Effectiveness of the approach is presented through numerical simulations and empirical results on electroporation efficiency and cell viability against various flow rates (exposure time to the field) as well as frequencies and root-mean-square (rms) intensities of the field. High frequencies (80–400 kHz) and high intensities (e.g., 1.6 kV/cm, rms) are identified with increased electroporation efficiency 61% and viability 86% on average. These results suggest that the device demonstrated here with a simple design and robust operation offers a viable platform for flow-through electroporation.
Strain engineered barium strontium titanate for tunable thin film resonators
Authors: Khassaf H. , Khakpash N. , Sun F. , Sbrockey N. M. , Tompa G. S. , Kalkur T. S. , Alpay S. P.
Published: May 2014

Piezoelectric properties of epitaxial (001) barium strontium titanate (BST) films are computed as functions of composition, misfit strain, and temperature using a non-linear thermodynamic model. Results show that through adjusting in-plane strains, a highly adaptive rhombohedral ferroelectric phase can be stabilized at room temperature with outstanding piezoelectric response exceeding those of lead based piezoceramics. Furthermore, by adjusting the composition and the in-plane misfit, an electrically tunable piezoelectric response can be obtained in the paraelectric state. These findings indicate that strain engineered BST films can be utilized in the development of electrically tunable and switchable surface and bulk acoustic wave resonators.
Nonlinear optical localization in embedded chalcogenide waveguide arrays
Authors: Li Mingshan , Huang Sheng , Wang Qingqing , Petek Hrvoje , Chen Kevin P.
Published: May 2014

We report the nonlinear optical localization in an embedded waveguide array fabricated in chalcogenide glass. The array, which consists of seven waveguides with circularly symmetric cross sections, is realized by ultrafast laser writing. Light propagation in the chalcogenide waveguide array is studied with near infrared laser pulses centered at 1040 nm. The peak intensity required for nonlinear localization for the 1-cm long waveguide array was 35.1 GW/cm2, using 10-nJ pulses with 300-fs pulse width, which is 70 times lower than that reported in fused silica waveguide arrays and with over 7 times shorter interaction distance. Results reported in this paper demonstrated that ultrafast laser writing is a viable tool to produce 3D all-optical switching waveguide circuits in chalcogenide glass.
Potential of crude extract and isolated compounds from golden beard grass (Chrysopogon serrulatus) for control of sprangletop (Leptochloa chinensis) in aerobic rice systems
Authors: Chuah T. S. , Oh H. Y. , Habsah M. , Norhafizah M. Z. , Ismail B. S.
Published: May 2014

Extraction and fractionation of the culm plus leaves of Chrysopogon serrulatus Trin. produce three major compounds, dibutyl phthalate (DBP), diphenylamine, 4,4′-dioctyl and simiarenol, which potentially act as allelochemicals or phytotoxic compounds. The effects of these compounds were examined using Leptochloa chinensis (L.) Nees as the bioassay species. The isolated compounds showed different degrees of inhibitory effects against L. chinensis. Of the three, DBP was the most potent and was able to inhibit L. chinensis germination by >70% at 500 mg L–1, followed by simiarenol and diphenylamine, 4,4′-dioctyl with inhibition values ranging from 40 to 52%. Under aerobic conditions, DBP at 2.4 kg a.i. ha–1 reduced the emergence and shoot fresh weight of L. chinensis by >50%, with negligible effect on root and shoot growth of aerobic rice seedlings, suggesting this as the most suitable rate and compound to control L. chinensis without injuring rice seedlings. At an application on the day of sowing rice seed, across DBP rates, reduction in root and shoot height of rice plants was evident when assessed 14 days after DBP treatment. However, rice plants become less susceptible with increasing growth stage. The findings suggest that DBP has potential to be developed as a pre-emergence, soil-applied natural herbicide for control of L. chinensis in aerobic rice system.
Genomic selection in crops, trees and forages: a review
Authors: Lin Z. , Hayes B. J. , Daetwyler H. D.
Published: May 2014

Genomic selection is now being used at an accelerating pace in many plant species. This review first discusses the factors affecting the accuracy of genomic selection, and then interprets results of existing plant genomic selection studies in light of these factors. Differences between genomic breeding strategies for self-pollinated and open-pollinated species, and between-population level v. within-family design, are highlighted. As expected, more training individuals, higher trait heritability and higher marker density generally lead to better accuracy of genomic breeding values in both self-pollinated and open-pollinated plants. Most published studies to date have artificially limited effective population size by using designs of bi-parental or within-family structure to increase accuracies. The capacity of genomic selection to reduce generation intervals by accurately evaluating traits at an early age makes it an effective tool to deliver more genetic gain from plant breeding in many cases.
Cbfβ deletion in mice recapitulates cleidocranial dysplasia and reveals multiple functions of Cbfβ required for skeletal development
Authors: Chen Wei , Ma Junqing , Zhu Guochun , Jules Joel , Wu Mengrui , McConnell Matthew , Tian Fei , Paulson Christie , Zhou Xuedong , Wang Lin , Li Yi-Ping
Published: May 2014

Significance

Cleidocranial dysplasia (CCD) is a hereditary human skeletal disease. Mutations in
Runt-related transcription factor 2
, which functions as a heterodimer with core binding factor β (Cbfβ), are found in most individuals with CCD. It has been suspected that Cbfβ may be responsible for other CCD cases. The pathogenesis of CCD and the role of Cbfβ in postnatal skeletogenesis remain unclear. There has been no animal model to study this disease. We demonstrate that ablation of Cbfβ in various skeletal cells results in severe craniofacial and skeletal dysplasia with the phenotype recapitulating clinical features of CCD. The findings from this study of Cbfβ in the skeleton provide insight into the role of Cbfβ in postnatal skeletogenesis and pathogenesis of CCD, which may assist in developing new therapies for CCD and osteoporosis.
Genomic landscape of CD34
+
hematopoietic cells in myelodysplastic syndrome and gene mutation profiles as prognostic markers
Authors: Xu Lan , Gu Zhao-Hui , Li Yang , Zhang Jin-Li , Chang Chun-Kang , Pan Chun-Ming , Shi Jing-Yi , Shen Yang , Chen Bing , Wang Yue-Ying , Jiang Lu , Lu Jing , Xu Xin , Tan Jue-Ling , Chen Yu , Wang Sheng-Yue , Li Xiao , Chen Zhu , Chen Sai-Juan
Published: May 2014

Significance

Myelodysplastic syndrome (MDS) represents a common hematopoietic disease, often in elderly patients, with heterogeneous clinical phenotypes and complex disease mechanisms. Here, we report on characteristic genome lesions, clonal architecture, and distinct tumor clone expansion patterns in a group of patients with refractory anemia with excess blasts, the MDS subtype with the highest propensity to acute myeloid leukemia. An integrative gene mutation analysis in 196 patients with different MDS subtypes allowed a regulatory network of mutually cooperative or exclusive molecules to be discovered among eight functional categories, whereas the combination of a panel of marker genes of prognostic value with the revised-International Prognostic Scoring System may provide a better stratification system for MDS.
Overview of Substance Use and Treatment from Australia
Authors: Haber Paul S. , Day Carolyn A.
Published: May 2014

This paper aims to provide an overview of drug and alcohol issues and their management in Australia. Overall, Australia has good health relative to the United States and other similar nations and generally similar rates of substance use disorders. A whole-of-government strategic approach has been developed for managing drug and alcohol problems, with a National Drug Strategy that has adopted a pragmatic approach to substance use problems through 3 “pillars”—demand, supply, and harm reduction. This approach has been attributed to Australia's remarkably low human immunodeficiency virus (HIV) prevalence among people who inject drugs (<2%). Most community primary health care is provided through Australia's universal health care scheme, which provides a rebate for nearly all medical services according to a scheduled fee. Inpatient and outpatient care, including drug and alcohol services, delivered at public hospitals are currently provided with no patient co-payments. The health of Australia's first peoples, Australian Aboriginals and Torres Strait Islanders, remains challenging primarily due to the transgenerational impacts of dispossession, social and economic disadvantage, and some cultural differences. Although substance use is a key issue for Australian Aboriginals, there are currently insufficient dedicated drug and alcohol services for this group. Notwithstanding this important exception, Australia's health and substance use is favorable relative to other developed nations, offering universal health care and a pragmatic drug and alcohol strategy.
A fungal prenyltransferase catalyzes the regular di-prenylation at positions 20 and 21 of paxilline
Authors: Liu Chengwei , Noike Motoyoshi , Minami Atsushi , Oikawa Hideaki , Dairi Tohru
Published: May 2014

A putative indole diterpene biosynthetic gene cluster composed of eight genes was identified in a genome database of Phomopsis amygdali, and from it, biosynthetic genes of fusicoccin A were cloned and characterized. The six genes showed significant similarities to pax genes, which are essential to paxilline biosynthesis in Penicillium paxilli. Recombinants of the three putative prenyltransferase genes in the cluster were overexpressed in Escherichia coli and characterized by means of in vitro experiments. AmyG is perhaps a GGDP synthase. AmyC and AmyD were confirmed to be prenyltransferases catalyzing the transfer of GGDP to IGP and a regular di-prenylation at positions 20 and 21 of paxilline, respectively. AmyD is the first know example of an enzyme with this function. The Km values for AmyD were calculated to be 7.6 ± 0.5 μM for paxilline and 17.9 ± 1.7 μM for DMAPP at a kcat of 0.12 ± 0.003/s.