bluuebunny/crossref_metadata_2025 huggingface dataset:
SePaS: Word sense disambiguation by

se

quential

pa

tterns in

s

entences
Authors: NAROUEI MASOUD , AHMADI MANSOUR , SAMI ASHKAN
Published: September 2013

An open problem in natural language processing is word sense disambiguation (WSD). A word may have several meanings, but WSD is the task of selecting the correct sense of a polysemous word based on its context. Proposed solutions are based on supervised and unsupervised learning methods. The majority of researchers in the area focused on choosing proper size of ‘n’ in n-gram that is used for WSD problem. In this research, the concept has been taken to a new level by using variable ‘n’ and variable size window. The concept is based on the iterative patterns extracted from the text. We show that this type of sequential pattern is more effective than many other solutions for WSD. Using regular data mining algorithms on the extracted features, we significantly outperformed most monolingual WSD solutions. The state-of-the-art results were obtained using external knowledge like various translations of the same sentence. Our method improved the accuracy of the multilingual system more than 4 percent, although we were using monolingual features.
Involvement of A20 in the molecular switch that activates the non-canonical NF-кB pathway
Authors: Yamaguchi Noritaka , Oyama Masaaki , Kozuka-Hata Hiroko , Inoue Jun-ichiro
Published: September 2013

The non-canonical NF-κB pathway is crucial for the immune system. A critical event in activation of the non-canonical pathway is the attenuation of NF-κB-inducing kinase (NIK) degradation, which is promoted by continuous polyubiquitination of NIK catalyzed by the NIK ubiquitin-ligase complex composed of cellular inhibitor of apoptosis protein 1 and 2 (cIAP1/2), TNF receptor-associated factor 2 (TRAF2) and TRAF3. However, the molecular mechanism of stimulation-dependent NIK stabilization remains poorly understood. Here, we show that A20, a ubiquitin-editing enzyme, promotes efficient activation of the non-canonical pathway independent of its catalytic activity. A20 directly binds to cIAP1 through the seventh zinc finger of A20, resulting in dissociation of the TRAF2/TRAF3 interaction, thereby inactivating the ligase complex to stabilize NIK. Given that A20 negatively regulates the canonical pathway, A20 is likely involved in the molecular switch that promotes the transition from canonical to non-canonical activation for proper control of the immune system.
Flexible asymmetric supercapacitors based on ultrathin two-dimensional nanosheets with outstanding electrochemical performance and aesthetic property
Authors: Shi Shan , Xu Chengjun , Yang Cheng , Chen Yanyi , Liu Juanjuan , Kang Feiyu
Published: September 2013

Flexible asymmetric supercapacitors with excellent electrochemical performance and aesthetic property are realized by using ultrathin two-dimensional (2D) MnO2 and graphene nanosheets as cathode and anode materials, respectively. 2D MnO2 nanosheets (MSs) with a thickness of ca. 2 nm are synthesized with a soft template method for the first time, which achieve a high specific capacitance of 774 F g−1 even after 10000 cycles. Asymmetric supercapacitors based on ultrathin MSs and graphene exhibit a very high energy density up to 97.2 Wh kg−1 with no more than 3% capacitance loss after 10000 cycles in aqueous electrolyte. Most interestingly, we show that the energy storage device can have an aesthetic property. For instance, a “Chinese panda” supercapacitor is capable of lighting up a red light emitting diode. This work has another, quite different aspect that a supercapacitor is no longer a cold industry product, but could have the meaning of art.
Natural Polysaccharides as Treatment Agents for Wastewater
Authors: Srinivasan Rajani
Published: September 2013

This chapter gives an account of recent developments in biopolymers with an emphasis on natural polysaccharides as treatment agents in wastewater remediation. Almost all sources of water around the world are polluted to some degree, owing to a heavy influx of industrial effluents, domestic and agricultural wastes. These discharges vary from simple nutrients to highly toxic hazardous chemicals. Numerous approaches have been studied for the development of cheaper and more effective water remediation agents containing natural polymers. Among these, natural polysaccharides deserve particular attention. These materials have proved to be better treatment alternatives compared to their synthetic counterparts because of their particular structure, physicochemical characteristics, chemical stability, high reactivity and excellent selectivity towards aromatic compounds, metals and other contaminants that cause water pollution.
Functionalized Silica Gel as Green Material for Metal Remediation
Authors: Sharma R. K. , Gaba Garima , Kumar Anil , Puri Aditi
Published: September 2013

Advancement in industrialization and urbanization is a good indicator of the progress of humanity. However, it has an evil side as well. This advancement is identified as being responsible for deleterious effects on the health of human beings and aquatic biodiversity. Anthropogenic activities like mining and disposal of treated/untreated waste effluents containing toxic metals have resulted in severe deterioration of water quality, rendering serious environmental problems. The basic problem is that the wastewater generated through industries is not given the necessary pretreatment and is discharged directly into water resources. The metals beyond their permissible limits cause maximum negative impacts owing to their long biological half-lives and nondegradable nature. The condition is further worsening in economically deprived countries, where this metal-contaminated wastewater is directly used in various agricultural and day-to-day practices. As a solution to this, the extraction and removal of toxic metal ions from these polluted water resources at an industrial level is of paramount importance. This chapter provides the enthusiastic efforts of the scientific community to disseminate the fundamentals and practices of green analytical methods for metal removal. These methods are based on solid-phase extraction using functionalized silica gel for the separation and preconcentration of metal ions in polluted water resources. Ease of synthesis and extensive application of these organic-inorganic hybrid materials helps to fulfil the commitment of continual environmental improvement by remediating the wastewater.
Applications of Ionic Liquids in Metal Extraction
Authors: Durga Geeta , Goyal Deepti , Mishra Anuradha
Published: September 2013

Ionic liquids are a promising class of new materials with a bright technological future. These materials are now being used in applications that are enabled by their presence as well as in applications where process performance outweighs their high cost. The aim of this chapter is to summarize the applications of ionic liquids in the extraction of different types of metals. It begins with a brief introduction to ionic liquids and then covers various types of ionic liquid used in different metal extraction processes.
Sample Collection, Storage and Preparation
Authors: Hyötyläinen Tuulia
Published: September 2013

The first steps of the workflow in metabolomics include sampling, sample pre‐processing and sample preparation. In this chapter, the sample types and sample preparation techniques utilized in metabolomics are presented. The sample preparation methods include homogenization, cell disruption, different extraction methods, such as liquid–liquid extraction, solid–liquid extraction, sample clean‐up and fractionation, and derivatization. Guidelines for the selection of the appropriate sample preparation method based on both the final analysis method and the type of sample and analytes are given.
Gas Chromatographic Techniques in Metabolomics
Authors: Wachsmuth Christian J. , Vogl Franziska C. , Oefner Peter J. , Dettmer Katja
Published: September 2013

High chemical diversity and abundances ranging from trace to millimolar levels still constitute at times insurmountable challenges in the comprehensive analysis of metabolites in biomedical specimens. Nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS) hyphenated with separation techniques such as liquid chromatography (LC), gas chromatography (GC) and capillary electrophoresis (CE) are the most frequently used techniques for both targeted and discovery‐driven metabolomics. Of the separation techniques, comprehensive two‐dimensional gas chromatography (GC×GC) offers the highest peak resolution and capacity, and in combination with MS lower quantification limits in the submicromolar concentration range are realized. Moreover, electron ionization (EI), the most prominent ionization technique for GC‐MS, is highly reproducible, facilitating the generation of mass spectral libraries for routine metabolite identification. However, GC analysis often requires a derivatization prior to analysis and not all metabolite derivatives are recorded in the libraries available. Consequently, metabolite identification is still a major challenge. To identify unknown metabolite signals, soft ionization techniques in combination with high‐resolution MS are employed to determine the accurate mass of the quasi‐molecular ion. The latter is used to calculate elemental formulae that can be fed into metabolite databases for a putative identification or used for the interpretation of EI spectra.
Supramolecular Approach for Tumor Imaging and Photodynamic Therapy
Authors: Gupta Anurag , Pandey Ravindra K.
Published: September 2013

Photodynamic therapy (PDT) is based on the concept that certain photosensitizers can be localized preferably in neoplastic tissue, and subsequently, these photosensitizers can be activated with the appropriate wavelength of light to generate active molecular species, such as free radicals and singlet oxygen (1O2), which are toxic to cells and tissues. Selectivity can be further enhanced by binding photosensitizers to molecular delivery systems and or by conjugating them with targeting agents such as monoclonal antibodies, integrin antagonists, carbohydrates and other moieties known to have high affinity to target tissues. Most photosensitizers are hydrophobic in nature and therefore require a shuttle to deliver them to a given target cell or tissue. Block copolymers, ceramic, vesicles, liposomes, gel encapsulation and pro-drug approaches are common examples for delivery of hydrophobic drugs. Supramolecular approaches (e.g. nanoparticles) are promising drug delivery systems for improving the bioavailability of poorly water soluble drugs. Functionalities can be added to nanomaterials by interfacing them with biological molecules or structures. Current trends are focused on developing supramolecular delivery systems in which biologically active species are covalently linked, encapsulated or postloaded to the biodegradable and biocompatible nanoparticles. Efforts are also underway in various laboratories to develop multifunctional agents (theranostics) for tumor-imaging and therapy. This particular chapter is focused on the recent advances of various synthetic and supramolecular (nanoparticles) approaches in molecular imaging and PDT and in particular the importance of polyacrylamide-based nanoplatforms in tumor-imaging and therapy.
Power signal disturbance identification and classification using a modified frequency slice wavelet transform
Authors: Biswal Birendra , Mishra Sukumar
Published: September 2013

This study presents a novel approach to localise, detect and classify non‐stationary power signal disturbances using a modified frequency slice wavelet transform (MFSWT). MFSWT is an extension of frequency slice wavelet transform (FSWT), which provides frequency‐dependant resolution with additional window parameters for better localisation of the spectral characteristics. An advantage of the MFSWT is attributed to the fact that the modulating sinusoids are fixed with respect to the time axis, whereas a localising scalable modified Gaussian window dilates and translates. Several practical power signals are considered for visual analysis using MFSWT, and the disturbance patterns are appropriately localised with unique signature corresponding to each type. This work also evaluates the detection capability of the proposed methodology and a comparison with earlier FSWT and Hilbert transform to show the superiority of proposed technique in detecting the power quality disturbances. A probabilistic neural network (PNN) based classifier is used for identifying the various disturbance classes. The spread parameter of the Gaussian activation function in PNN is tuned and its effect on the classification at different strengths of noise is studied.
Reference Correlation of the Viscosity of n-Hexane from the Triple Point to 600 K and up to 100 MPa
Authors: Michailidou E. K. , Assael M. J. , Huber M. L. , Perkins R. A.
Published: September 2013

This paper contains new, representative reference equations for the viscosity of n-hexane. The equations are based in part upon a body of experimental data that has been critically assessed for internal consistency and for agreement with theory whenever possible. The correlations are valid from the triple point to 600 K, and at pressures up to 100 MPa. We estimate the expanded uncertainty at a 95% confidence level to be 2% for the liquid phase at temperatures from the triple point to 450 K and pressures to 100 MPa. For the liquid at 450–600 K at pressures to 100 MPa, the expanded uncertainty at the 95% confidence level is 6%, and is 0.3% for the low-density gas at pressures to 0.3 MPa.
A coarse grain model for protein-surface interactions
Authors: Wei Shuai , Knotts Thomas A.
Published: September 2013

The interaction of proteins with surfaces is important in numerous applications in many fields—such as biotechnology, proteomics, sensors, and medicine—but fundamental understanding of how protein stability and structure are affected by surfaces remains incomplete. Over the last several years, molecular simulation using coarse grain models has yielded significant insights, but the formalisms used to represent the surface interactions have been rudimentary. We present a new model for protein surface interactions that incorporates the chemical specificity of both the surface and the residues comprising the protein in the context of a one-bead-per-residue, coarse grain approach that maintains computational efficiency. The model is parameterized against experimental adsorption energies for multiple model peptides on different types of surfaces. The validity of the model is established by its ability to quantitatively and qualitatively predict the free energy of adsorption and structural changes for multiple biologically-relevant proteins on different surfaces. The validation, done with proteins not used in parameterization, shows that the model produces remarkable agreement between simulation and experiment.
Solvent dependence of Stokes shift for organic solute–solvent systems: A comparative study by spectroscopy and reference interaction-site model–self-consistent-field theory
Authors: Nishiyama Katsura , Watanabe Yasuhiro , Yoshida Norio , Hirata Fumio
Published: September 2013

The Stokes shift magnitudes for coumarin 153 (C153) in 13 organic solvents with various polarities have been determined by means of steady-state spectroscopy and reference interaction-site model–self-consistent-field (RISM–SCF) theory. RISM–SCF calculations have reproduced experimental results fairly well, including individual solvent characteristics. It is empirically known that in some solvents, larger Stokes shift magnitudes are detected than anticipated on the basis of the solvent relative permittivity, ɛr. In practice, 1,4-dioxane (ɛr = 2.21) provides almost identical Stokes shift magnitudes to that of tetrahydrofuran (THF, ɛr = 7.58), for C153 and other typical organic solutes. In this work, RISM–SCF theory has been used to estimate the energetics of C153–solvent systems involved in the absorption and fluorescence processes. The Stokes shift magnitudes estimated by RISM–SCF theory are ∼5 kJ mol−1 (400 cm−1) less than those determined by spectroscopy; however, the results obtained are still adequate for dipole moment comparisons, in a qualitative sense. We have also calculated the solute–solvent site–site radial distributions by this theory. It is shown that solvation structures with respect to the C–O–C framework, which is common to dioxane and THF, in the near vicinity (∼0.4 nm) of specific solute sites can largely account for their similar Stokes shift magnitudes. In previous works, such solute–solvent short-range interactions have been explained in terms of the higher-order multipole moments of the solvents. Our present study shows that along with the short-range interactions that contribute most significantly to the energetics, long-range electrostatic interactions are also important. Such long-range interactions are effective up to 2 nm from the solute site, as in the case of a typical polar solvent, acetonitrile.
Magnetic characteristics of phase-separated CeO2:Co thin films
Authors: Prestgard M. C. , Siegel G. , Ma Q. , Tiwari A.
Published: September 2013

Herewith, we are reporting the magnetic properties of phase-separated Co-doped CeO2 films (with a Ce:Co atomic-ratio of 0.97:0.03) grown on single-crystal SrTiO3 (001) substrates. A comparison of the magnetic characteristics of these films with those of homogenously doped CeO2:Co films of the same composition illustrates the significant differences in their magnetic behavior. These behavioral characteristics provide a model for determining if the magnetic behavior observed in this, as well as in other diluted magnetic dielectric systems, is due to homogeneous doping, a mixture of doping and transition metal cluster formation, or exists purely as a result of transition metal clustering.
Multiscale shear-strain gradient for detecting delamination in composite laminates
Authors: Cao M. S. , Ostachowicz W. , Radzieński M. , Xu W.
Published: September 2013

Delamination is a typical failure mode in composite laminates. For detecting delamination, a new physical concept of a multiscale shear-strain gradient (MSG) is formulated from a vibrational mode shape of a Kirchhoff plate. In a laminate containing a small delamination, the MSG characterizes shear-strain singularities with an explicit physical implication and no need for material properties, in turn manifesting the distribution of the delamination; moreover, multiscale property enables the MSG to identify delaminations at a high noise level. Numerical and experimental results show that the MSG defies the traditional understanding that vibrational features are inappropriate to localize a slight delamination.
Band tailing and efficiency limitation in kesterite solar cells
Authors: Gokmen Tayfun , Gunawan Oki , Todorov Teodor K. , Mitzi David B.
Published: September 2013

We demonstrate that a fundamental performance bottleneck for hydrazine processed kesterite Cu2ZnSn(S,Se)4 (CZTSSe) solar cells with efficiencies reaching above 11% can be the formation of band-edge tail states, which quantum efficiency and photoluminescence data indicate is roughly twice as severe as in higher-performing Cu(In,Ga)(S,Se)2 devices. Low temperature time-resolved photoluminescence data suggest that the enhanced tailing arises primarily from electrostatic potential fluctuations induced by strong compensation and facilitated by a lower CZTSSe dielectric constant. We discuss the implications of the band tails for the voltage deficit in these devices.
Exploration of microfluidic devices based on multi-filament threads and textiles: A review
Authors: Nilghaz A. , Ballerini D. R. , Shen W.
Published: September 2013

In this paper, we review the recent progress in the development of low-cost microfluidic devices based on multifilament threads and textiles for semi-quantitative diagnostic and environmental assays. Hydrophilic multifilament threads are capable of transporting aqueous and non-aqueous fluids via capillary action and possess desirable properties for building fluid transport pathways in microfluidic devices. Thread can be sewn onto various support materials to form fluid transport channels without the need for the patterned hydrophobic barriers essential for paper-based microfluidic devices. Thread can also be used to manufacture fabrics which can be patterned to achieve suitable hydrophilic-hydrophobic contrast, creating hydrophilic channels which allow the control of fluids flow. Furthermore, well established textile patterning methods and combination of hydrophilic and hydrophobic threads can be applied to fabricate low-cost microfluidic devices that meet the low-cost and low-volume requirements. In this paper, we review the current limitations and shortcomings of multifilament thread and textile-based microfluidics, and the research efforts to date on the development of fluid flow control concepts and fabrication methods. We also present a summary of different methods for modelling the fluid capillary flow in microfluidic thread and textile-based systems. Finally, we summarized the published works of thread surface treatment methods and the potential of combining multifilament thread with other materials to construct devices with greater functionality. We believe these will be important research focuses of thread- and textile-based microfluidics in future.
Perspective: Graphene aerogel goes to superelasticity and ultraflyweight
Authors: Xu Zhen , Sun Haiyan , Gao Chao
Published: September 2013

Three-dimensional graphene-based aerogels have been promoted to present fascinating superelasticity and ultralightness by the intelligent design on microstructures. In this perspective, we conclude the recent design strategies to realize these dual elasticity and lightness, and look forward to the promising applications of graphene-based aerogels with multifunctional merits.
Photoconductive ZnO films with embedded quantum dot or ruthenium dye sensitizers
Authors: White Michael A. , Dempsey Jillian L. , Carroll Gerard M. , Gallagher James D. , Gamelin Daniel R.
Published: September 2013

We report a new type of solution-processed photoconductive film based on embedding photosensitizers (semiconductor nanocrystals or ruthenium dye molecules) within conductive ZnO sol-gel matrices. Mixing photosensitizers directly with sol-gel precursors prior to film deposition yields highly colored ZnO films containing well-dispersed sensitizers. These films show internal photoconductivity quantum efficiencies up to ∼50% and photoresponses over 100 mA/W with visible photoexcitation, competitive with other more complex photodetectors reported recently. This simple motif is attractive for the development of robust sensitized-oxide photodetectors and for fundamental studies of photoinduced charge separation from a variety of molecular or quantum dot sensitizers into conductive oxides.
The effect of specimen surface curvature on x-ray diffraction peak profiles
Authors: Zhigachev Andrey O.
Published: September 2013

The effect of specimen surface curvature on profiles of asymmetric X-ray diffraction peaks obtained using the Bragg-Brentano geometry with a position sensitive detector (PSD) was studied. Asymmetric diffraction peaks were experimentally obtained from cylindrical surfaces with controlled curvature. Peaks were collected for a set of curvature radii, diffraction angles, and materials. A mathematical approach and a computer model for calculations of peak profiles were developed: a general method for computation of peak profiles is consideration of diffraction cones intersection with the PSD surface. Effects of axial and radial divergence, finite sample size, and local surface tilt were included in the model. Calculated peak profiles agree with reflections obtained experimentally at a wide range of curvature radii and diffraction angle values. Computation of important characteristics such as the peak centroid and change in position of the maximum and full-width-half-maximum is provided.
Rashba-induced spin scattering at graphene edges
Authors: Liu Feilong , Liu Yue , Hu Jiaxi , Smith Darryl L. , Paul Ruden P.
Published: September 2013

We investigate theoretically the behavior of electron spin states near graphene edges at low temperature in the presence of an external electric field. The graphene Hamiltonian is solved directly in the low energy regime including the Rashba spin-orbit interaction. Spin propagation in graphene and spin reflection at the edge are explored by calculating the probability of spin flips between the final and initial states. The spin scattering at the edge is affected by the initial location and the propagating direction of the electron with respect to the edge. Results for an example device structure including the effects of the non-uniform electrostatic field and potential near the graphene edge are presented.
Coherent acoustic phonon generation and detection by femtosecond laser pulses in ZnTe single crystals
Authors: Feng D. H. , Pan X. Q. , Li X. , Jia T. Q. , Sun Z. R.
Published: September 2013

We report experiments of coherent acoustic phonon generations and detections using a two-color femtosecond pump-probe technique in [001] and [110] oriented ZnTe single crystals. The above-bandgap pump excitation initiates strain waves to yield coherent acoustic phonons. The generation and propagation of coherent acoustic waves not only modulate the intensity of the reflected probe light but also change its polarization periodically due to strain-induced birefringence. The nonuniform excitation due to Gaussian spatial distribution of pump pulses takes an important role in the polarimetric detection of coherent acoustic phonon oscillations.
Granular metamaterials for vibration mitigation
Authors: Gantzounis G. , Serra-Garcia M. , Homma K. , Mendoza J. M. , Daraio C.
Published: September 2013

Acoustic metamaterials that allow low-frequency band gaps are interesting for many practical engineering applications, where vibration control and sound insulation are necessary. In most prior studies, the mechanical response of these structures has been described using linear continuum approximations. In this work, we experimentally and theoretically address the formation of low-frequency band gaps in locally resonant granular crystals, where the dynamics of the system is governed by discrete equations. We investigate the quasi-linear behavior of such structures. The analysis shows that a stopband can be introduced at about one octave lower frequency than in materials without local resonances. Broadband and multi-frequency stopband characteristics can also be achieved by strategically tailoring the non-uniform local resonance parameters.
Interaction in ferromagnetic thin film across an antiferromagnetic layer
Authors: Tang Xiao-Li , Weiwei Du , Su Hua , Zhang Huai-Wu , Zhong Zhi-Yong , Jing Yu-Lan
Published: September 2013

NiFe (5 nm)/IrMn (15 nm)/NiFe (t nm) dual exchange bias systems with various thicknesses of top NiFe layers were grown in a magnetic field. Magnetometry studies revealed that the exchange bias field Hex at the bottom NiFe/IrMn interface of fixed thickness increased when the Hex at the top IrMn/NiFe interface increased. The bottom Hex increased linearly with the decrease in thickness of the top pinned layer. Furthermore, the Hex values achieved in the bottom NiFe/IrMn interface in the dual exchange bias samples were all larger than that of the same thickness of NiFe/IrMn bilayer. In addition, by comparison of NiFe/IrMn/NiFe and Cu/IrMn/NiFe with similar microstructures, Hex achieved in the top NiFe/IrMn interface was found to be large in the dual exchange bias system. These results provide evidence of the interaction in the dual exchange-coupling system across the antiferromagnetic layer.
First-principles calculation of intrinsic carrier mobility of silicene
Authors: Shao Zhi-Gang , Ye Xue-Sheng , Yang Lei , Wang Cang-Long
Published: September 2013

The intrinsic carrier mobility of silicene is calculated using first-principles methods incorporating density functional theory, Boltzman transport equation, and the deformation potential theory. The electron mobility is 2.57×105 cm2V-1s-1 and the hole mobility is 2.22×105 cm2V-1s-1 at room temperature, which is smaller than that of graphene but still very high.
Effects of point defect healing on phosphorus implanted germanium n+/p junction and its thermal stability
Authors: Shim Jaewoo , Shin Jeong-hun , Lee In-Yeal , Choi Daebeom , Woo Baek Jung , Heo Jonggon , Park Wonkyu , Woo Leem Jung , Su Yu Jae , Jung Woo-Shik , Saraswat Krishna , Park Jin-Hong
Published: September 2013

In this work, the effect of Ge point defect healing process between 550 °C and 650 °C is investigated, in the aspect of leakage (off) current and junction depth of Ge n+/p junction diodes using ECV, TEM, J-V, and SIMS analyses. After 600 °C anneal, off-current density (2 × 10−4 A/cm2) is dramatically reduced due to the defect healing phenomenon that decreases the number of point defects, subsequently providing a higher on/off-current ratio of 5 × 103. In spite of the high healing temperature, junction diodes seem not to suffer from the deep diffusion of phosphorus (P) in Ge because those diffuse mostly through VGe. In addition, it is also confirmed that Ti is an appropriate material in terms of diffusion barrier and diffusivity for Ge n+/p junction contact metal.
Shear avalanches in metallic glasses under nanoindentation: Deformation units and rate dependent strain burst cut-off
Authors: Bian X. L. , Wang G. , Chan K. C. , Ren J. L. , Gao Y. L. , Zhai Q. J.
Published: September 2013

Indented metallic glasses at the nanoscale deform via strain bursts. Conventional continuum descriptions are not appropriate for such highly stochastic, intermittent deformations. In this study, after a statistical analysis of strain bursts in five metallic glasses, the dependence of the cut-off of the strain burst size on deformation units and loading rate is established. For soft metallic glasses with smaller deformation units, cut-off of the strain burst size truncates the scale-free behavior at larger strain burst sizes. For hard metallic glasses, scale-free behavior occurs in a wide range of strain burst sizes.
Flame pyrolysis synthesis of self-oriented carbon nanotubes
Authors: Sun B. M. , Cao W. H. , Guo Y. H. , Wang Y. , Luo J. T. , Jiang P.
Published: September 2013

In this paper, the flame pyrolysis method to synthesize self-oriented carbon nanotubes (CNTs) with Fe/Mo/Al2O3 as catalyst is studied. The outcome arrays are well aligned and relatively good in morphology. Furthermore, after electric field being applied to flame pyrolysis synthesis, the arrays become straighter and longer significantly, with higher yield.
Lifecycle Stages and Residential Location Choice in the Presence of Latent Preference Heterogeneity
Authors: Smith Brett , Olaru Doina
Published: September 2013

The choice of residential locations is affected by both dwelling and location characteristics. Preferences for these characteristics vary with each household's requirements, traditionally attributed to the household's lifecycle stage. With a cross-sectional study that identifies lifecycle stages according to household structure, this paper offers an investigation of residential location and shows that not all components of preference heterogeneity can be accounted for by household structure. Latent class choice models examine household segments according to lifestyle preferences. The results reveal the degree of association between identified household lifecycle segments and estimated lifestyle latent classes. The composition of the latent structure differs for each lifecycle segment; income and the age of the head of household strongly affect housing preferences, but do not lead to the same latent class structure for households at different lifecycle stages.
Extinct habitat, extant species: lessons learned from conservation recovery actions for the Pedder galaxias (Galaxias pedderensis) in south-west Tasmania, Australia
Authors: Chilcott Stuart , Freeman Rob , Davies Peter E. , Crook David A. , Fulton Wayne , Hamr Premck , Jarvis David , Sanger Andrew C.
Published: September 2013

The Pedder galaxias (Galaxias pedderensis) from Lake Pedder, Tasmania, Australia, is one of the world’s most threatened freshwater fish. The flooding of Lake Pedder in 1972 for hydroelectric power generation caused a major change to the ecosystem that initiated an irreversible decline in the Pedder galaxias within its natural range. The flooding inundated another headwater catchment and native and introduced fish from this catchment colonised the impoundment. Numbers of the Pedder galaxias declined markedly as the impoundment matured and as colonising fish proliferated. Surveys in the 1980s confirmed the parlous state of the population, highlighting the need for conservation intervention. Several urgent conservation actions were undertaken to save the species from extinction. Translocation was considered the most important recovery action, given the critically low numbers in the wild. The species is now extinct from its natural range and is known from only two translocated populations. The conservation program, and specifically the translocation recovery action, saved the Pedder galaxias from extinction. The conservation management was extremely challenging since rapidly declining fish numbers needed timely and critical decisions to underpin the future of the fish. Recommendations are provided arising from this case study to guide conservation of freshwater fish in similar circumstances.
Freshwater fish conservation in the face of critical water shortages in the southern Murray–Darling Basin, Australia
Authors: Hammer Michael P. , Bice Christopher M. , Hall Arkellah , Frears Adrienne , Watt Adam , Whiterod Nick S. , Beheregaray Luciano B. , Harris James O. , Zampatti Brenton P.
Published: September 2013

The lower reaches of the expansive Murray–Darling Basin, Australia, are a hotspot for freshwater biodiversity. The regional ecosystem, however, has been significantly altered by river regulation, including local and catchment-wide water abstraction. Freshwater fishes have suffered from the resultant altered flow regime, together with other threats including habitat degradation and alien species. Impacts reached a critical point (imminent species extinction) during a prolonged drought (1997–2010) that lead to broad-scale habitat loss and drying of refuges during 2007–2010, and urgent conservation measures were subsequently instigated for five threatened small-bodied fish species. A critical response phase included ad hoc interventions that were later incorporated within a broader, coordinated multi-agency program (i.e. the Drought Action Plan and Critical Fish Habitat projects). On-ground actions included local translocation, alien species control, in situ habitat maintenance (e.g. earthworks, environmental water delivery), fish rescues, artificial refuge establishment and captive breeding. Improved river flows signalled an initial phase of recovery in 2011–2012 that included reintroductions. The present paper aims to document the actions undertaken in the Lower Murray, and review successes and lessons from practical examples that will help guide and inform management responses to conserve fish in modified systems subjected to severe water decline.
Prospects of elimination of HIV with test-and-treat strategy
Authors: Kretzschmar Mirjam E. , Schim van der Loeff Maarten F. , Birrell Paul J. , De Angelis Daniela , Coutinho Roel A.
Published: September 2013

Recently, there has been much debate about the prospects of eliminating HIV from high endemic countries by a test-and-treat strategy. This strategy entails regular HIV testing in the entire population and starting antiretroviral treatment immediately in all who are found to be HIV infected. We present the concept of the elimination threshold and investigate under what conditions of treatment uptake and dropout elimination of HIV is feasible. We used a deterministic model incorporating an accurate description of disease progression and variable infectivity. We derived explicit expressions for the basic reproduction number and the elimination threshold. Using estimates of exponential growth rates of HIV during the initial phase of epidemics, we investigated for which populations elimination is within reach. The concept of the elimination threshold allows an assessment of the prospects of elimination of HIV from information in the early phase of the epidemic. The relative elimination threshold quantifies prospects of elimination independently of the details of the transmission dynamics. Elimination of HIV by test-and-treat is only feasible for populations with very low reproduction numbers or if the reproduction number is lowered significantly as a result of additional interventions. Allowing low infectiousness during primary infection, the likelihood of elimination becomes somewhat higher. The elimination threshold is a powerful tool for assessing prospects of elimination from available data on epidemic growth rates of HIV. Empirical estimates of the epidemic growth rate from phylogenetic studies were used to assess the potential for elimination in specific populations.
Weighted means and Karcher equations of positive operators
Authors: Lawson Jimmie , Lim Yongdo
Published: September 2013

Significance

As positive matrices and operators have gained increased prominence in theoretical, applied, and computational settings, finding appropriate methods for averaging them has become an important task. In recent years, the minimizer of the (weighted) sum of the distances (in an appropriately chosen metric) to the points to be averaged has been shown to exhibit many attractive features. In this paper, we extend most of these results to the infinite-dimensional setting, where the metric definition needs to be replaced by a solution shown to be unique of a corresponding equation called the Karcher equation. A multivariable weighted operator mean results that in many senses generalizes the geometric mean of a finite number of positive real numbers.
Adaptive hydrophobic and hydrophilic interactions of mussel foot proteins with organic thin films
Authors: Yu Jing , Kan Yajing , Rapp Michael , Danner Eric , Wei Wei , Das Saurabh , Miller Dusty R. , Chen Yunfei , Waite J. Herbert , Israelachvili Jacob N.
Published: September 2013

Significance

Two popular perceptions about the much-mimicked adhesion of mussels are (
i
) the adhesion depends entirely on 3, 4-dihydroxyphenylalanine (Dopa) groups (benzene derivatives with two H-bonding prongs) and (
ii
) Dopa can stick to all surfaces. This study shows that both perceptions are incorrect: using three Dopa-containing mussel foot proteins (Mfps) on two chemically different self-assembled monolayers (SAM), we found the highest adhesion on the nonpolar (i.e., hydrophobic) SAMs was exhibited by the Mfp with the most hydrophobic side chains, not the most Dopa. Furthermore, increasing the spacing between the H-bond acceptors in the SAMs prevented the double-pronged H-bonding of Dopa side chains to polar SAMs. These findings clarify the roles of hydrophobic and hydrophilic interactions in both biological and nonbiological adhesion.
Language Problems and Language Planning
Authors: Li Wenwen , Liu Haitao
Published: September 2013

As one of the most authoritative journals in the field of language planning, Language Problems and Language Planning has a long history. In this paper, we describe the development and changes that the journal has experienced in different periods, the characteristics that have remained constant, and the role that it has played in the development of language planning. To this end, we collected information from the first 100 issues of the journal (1977 to 2010) to build a corpus, and then used software to extract different categories of information. Through analysis of these statistics, we found that the journal is in many respects representative of changes in the field of language planning, following trends in the discipline and clearly and accurately reflecting the evolving priorities of language planning over the years.
Conservation of the Owens Pupfish: Genetic Effects of Multiple Translocations and Extirpations
Authors: Finger Amanda J. , Parmenter Steve , May Bernie P.
Published: September 2013

The Owens Pupfish Cyprinodon radiosus represents many of the challenges of managing threatened or endangered species in fragmented refuge populations. All six extant populations of the endangered Owens Pupfish were examined to assess how management practices, including serial translocations and founder events, have influenced the genetic diversity of the species and to make recommendations for future management. Four populations were sampled twice with 3–4 years intervening; two additional populations were sampled once. Populations were genotyped at nine microsatellite loci; estimated effective population sizes ranged from 34.2 to 347.8 individuals based on the linkage disequilibrium method and from 10 to 48 using the sibship assignment method. All of the populations were estimated to have undergone severe bottlenecks, and statistically significant pairwise FST values increased during the period between sampling. From this data we infer that the individual refuge populations have differentiated and lost genetic diversity and that without intervention they will continue to do so. For the long‐term persistence of this species, we recommend founding new populations composed of 30–50 founders from each of the extant populations, regularly translocating up to 10 migrants per generation among stable populations, and maximizing habitat area and quality.
Stereotype Threat can Reduce Older Adults' Memory Errors
Authors: Barber Sarah J. , Mather Mara
Published: September 2013

Stereotype threat often incurs the cost of reducing the amount of information that older adults accurately recall. In the current research, we tested whether stereotype threat can also benefit memory. According to the regulatory focus account of stereotype threat, threat induces a prevention focus in which people become concerned with avoiding errors of commission and are sensitive to the presence or absence of losses within their environment. Because of this, we predicted that stereotype threat might reduce older adults' memory errors. Results were consistent with this prediction. Older adults under stereotype threat had lower intrusion rates during free-recall tests (Experiments 1 and 2). They also reduced their false alarms and adopted more conservative response criteria during a recognition test (Experiment 2). Thus, stereotype threat can decrease older adults' false memories, albeit at the cost of fewer veridical memories, as well.
Development of a Nonlethal and Minimally Invasive Protocol to Study Elasmobranch Reproduction
Authors: Prohaska Bianca K. , Tsang Paul C. W. , Driggers William B. , Hoffmayer Eric R. , Sulikowski James A.
Published: September 2013

An understanding of basic reproductive biology is essential for successful species-specific management of elasmobranch fishes (sharks, skates, and rays). Such information is often gained through gross dissection or other lethal techniques, which are not appropriate for threatened and endangered species. Previous work on other vertebrates suggested that sex steroid hormones can be extracted from muscle tissues to identify reproductive status. Collecting for muscle biopsy is quick and minimally invasive and can be done without removing an animal from the water. Thus, the objective of the current study was to determine the efficacy of using muscle steroid hormones to assess the reproductive biology of elasmobranch fishes. The results suggest that concentrations of muscle progesterone, testosterone, and estradiol can be successfully quantified to study reproduction by radioimmunoassay. Additionally, there were significant correlations between the plasma and muscle estradiol concentrations in Spiny Dogfish Squalus acanthias and the progesterone, testosterone, and estradiol concentrations in Atlantic Sharpnose Sharks Rhizoprionodon terraenovae. The present investigation thus demonstrates that skeletal muscle is a nonlethally harvestable tissue that is well suited for studying the reproductive biology of elasmobranchs.

Received October 12, 2012; accepted March 12, 2013
Patterns and processes of habitat-specific demographic variability in exploited marine species
Authors: Vasconcelos Rita P. , Eggleston David B. , Le Pape Olivier , Tulp Ingrid
Published: September 2013

Population dynamics are governed by four demographic rates: births, deaths, immigration, and emigration. Variation in these rates and processes underlying such variation can be used to prioritize habitat conservation and restoration as well as to parameterize models that predict habitat-specific effects on population dynamics. The current understanding of patterns of habitat-specific demographic variability in exploited marine species, as well as processes underlying these patterns, was reviewed. We describe patterns of (i) habitat-specific density, followed by ontogenetic changes in habitat use, such as (ii) immigration (i.e. use as a settlement habitat) and (iii) emigration (i.e. use as a habitat for secondary dispersal to and from), and demographic rates such as (iv) growth, and (v) mortality. Despite the importance of coastal habitats for fish and invertebrate species and the vulnerability of these habitats to human impacts, there was ambiguous evidence on their role in driving of population dynamics. Roughly 63% of the studies were descriptive, 21% experimental, and 11% used a combination of descriptive and experimental approaches, whereas 5% used meta-analyses. Habitat-specific density was the most common pattern quantified, followed by growth and mortality, with relatively few examples of studies of habitat-specific larval settlement. There were many examples of the influence of coastal habitats on survival, growth, and movement, especially at young stages, and there was an emerging focus on the effects of habitat degradation on demographic rates. There needs to be an increased effort on quantifying habitat-specific demographic rates and integrating these to better predict the effects of coastal habitats on the dynamics of exploited marine populations.
Kodamaea transpacifica f.a., sp. nov., a yeast species isolated from ephemeral flowers and insects in the Galápagos Islands and Malaysia: further evidence for ancient human transpacific contacts
Authors: Freitas Larissa F. D. , Barriga Enrique Javier Carvajal , Barahona Patricia Portero , Lachance Marc-André , Rosa Carlos A.
Published: September 2013

Twenty-four yeast strains were isolated from ephemeral flowers of Ipomoea spp. and Datura sp. and their associated insects in the Galápagos Archipelago, Ecuador, and from Ipomoea spp. and associated insects in the Cameron Highlands, Malaysia. Sequences of the D1/D2 domains of the large subunit rRNA gene indicated that these strains belong to a novel yeast species of the Kodamaea clade, although the formation of ascospores was not observed. The closest relative is Candida restingae. The human-mediated dispersion of this species by transpacific contacts in ancient times is suggested. The name Kodamaea transpacifica f.a., sp. nov. is proposed to accommodate these isolates. The type strain is CLQCA-24i-070T ( = CBS 12823T = NCYC 3852T); MycoBank number MB 803609.