bluuebunny/crossref_metadata_2025 huggingface dataset:
Plane Wave Diffraction by an Open Parallel Plate Waveguide with Dielectric Loading
Authors: Türetken Bahattin , Alkumru Ali
Published: June 2016

The diffraction of plane electromagnetic waves by an open parallel plate waveguide with dielectric loading is investigated rigorously by using the Fourier transform technique. This method of formulation gives rise to Wiener- Hopf equations. The solution of each Wiener-Hopf equation contains a set of infinitely many constants satisfying an infinite system of linear algebraic equations. A numerical solution of this systems is obtained for various values of the distances between the plates, plate thickness, the number of wave in the dielectric region.
The Boundary Integral Equation Method for Elastoplastic Stres Analysis of Frictional Contact Problems
Authors: Gun Halit , Becker A.
Published: June 2016

For two-dimensional elastoplastic stress analysis of frictional contact problems an isoparametric quadratic formulation of the boundary integral equation (BIE) method is presented with emphasis on clarity at the expense of efficiency. The overall system of equation is obtained by using multi-domain approach in which the contact conditions are taken into account to couple the different system of equation for each body in contact, Several types of contact interface conditions are covered including Infinite friction (stick), frictionless and Coulomb friction slip. In order to include plastic deformation in the analysis, the initial strain formulation and von Mises yield criterion are used. In order to evaluate internal stress and strain rates the differentiation of the displacement in elementwise manner is adopted with its compulsory modeling of partial (where plastic deformation is expected) domain. Elastic-perfectly plastic, work-hardening or mixed hardening material behaviour can be assumed. An efficient and robust incremental-iterative process is proposed to find the proper contact conditions. For the numerical implementation, isoparametric three-noded line elements are used to represent the boundary and eight-noded quadrilateral domain cell are used for partially modelling interior domain. The proposed algorithm is applied to the heftz-like indentation problem and the results are, where appropriate, compared with the presented results in the literature to confirm its correctness and robustness.
Calculation of the Natural Frequencies of a Beam–Mass System Using Finite Element Method
Authors: Öz H.R.
Published: June 2016

In this study, the natural frequencies of an Euler-Bernoulli type beam with a mass are calculated. The beam is supported with different end conditions. The mass is located on different locations. The linear natural frequencies are calculated by using finite element method for the first five modes. Results are compared with those of exact and other approximate methods.
A Comparison of Chaotic Circuits from a Statistical Approach
Authors: KURT E. , ACAR S. , KASAP R.
Published: June 2016

In this paper, we have investigated the chaotic structure of two different nonlinear circuits by a statistical approach and compared the results of analyses for these systems. We have utilized time history technique to identify the dynamic system. According to the results of the analysis using the BDS test, it has been found that each time series data belonging to circuits indicate chaotic behavior in some cases.
On the Nonlinear Transverse Vibrations and Stability of an Axially Accelerating Beam
Authors: Öz H.
Published: June 2016

Nonlinear vibrations and stability analysis of an axially moving Euler-Bernoulli type beam are investigated. The beam is on fixed supports and moving with a harmonically varying velocity about a constant mean value. The method of multiple scales is used in the analysis. Nonlinear frequencies depending on vibration amplitudes are obtained. Stability and bifurcations of steady-state solutions are analyzed for frequencies close to two times any natural frequency. It is shown that the amplitudes are bounded in time for frequencies close to zero. The effect of fixed supports is discussed.
Frictionless Contact Problem between an Elastic Layer Bonded to a Rigid Support and a Rigid Stamp
Authors: Kahya Volkan , Birinci Ahmet , Erdöl Ragıp
Published: June 2016

The plane contact problem for an elastic layer bonded to a rigid support on its top surface is considered according to the theory of elasticity. The layer is subjected to a concentrated load at its bottom surface by means of a rigid stamp. Profile of the rigid stamp is taken in the form as circular, parabolic and rectangular. It is assumed that the contact between the layer and the stamp is frictionless and that only compressive normal tractions can be transmitted through the interface. The problem is formulated in terms of a singular integral equation. Numerical results for various dimensionless quantities are presented and discussed.
An Analytical Elastic-Plastic Stress Analysis for a Steel Fibre Reinforced Thermoplastic Composite Beam Subjected to Thermal Loading
Authors: Çallıoğlu H. , Şenel M. , Savran M.
Published: June 2016

This paper is concerned with a thermal elastic-plastic stress analysis on a steel fibre reinforced thermoplastic matrix composite beam fixed at its to ends. Temperature varying linearly is chosen at the upper and lower surfaces to be zero and T0, respectively. The solution is performed at 0, 60, 75 and 90° orientation angles. Plastic yielding does not occur at 30 and 45° orientation angles. It is found that the intensity of the residual stress component of σx and the equivalent plastic strain are maximum at the lower surface of the beam. The intensity of the residual stress is maximum at 0° orientation angle. The intensity of the equivalent plastic strain is found to be the greatest at 60° orientation angle.
Application of Holditch Theorem to Bezier and Quadratic Uniform B-Spline Curves
Authors: Caliskan A. , Tantay B.
Published: June 2016

Parametric polynomial functions are one of the most common types of functions that are used in curve and surface design. Bezier and quadratic uniform B-Spline curves are some common examples of those functions. Crossectional areas between these curves have great importance in computer aided geometric design (CAGD) and computer aided geometric manufacturing (CAM). While calculating these areas, the kind of the curves and surfaces of which the objects are composed, is very important. After determining the types of the curves, we choose one of the most suitable methods to calculate the area. In this paper, we used Holditch Theorem to calculate the areas between two Bezier curves and two quadratic uniform B-Spline curves.
Some Generating Function Relations of Multiindex Hermite Polynomials
Authors: Shrivastava HSP
Published: June 2016

In the present some generating functions relations of Hermite polynomial also of two, three and in turn several index are derived. Some known and unknown particular cases have also been discussed.
Possibility of Practical Using of Electric Field in Transportation Systems
Authors: Hassanov Hikmet
Published: June 2016

Liquid motion in pipes under electric field action has been theoretically and experimentally investigated for the first time. Essential dependences of liquid properties on electric field are found. Flowrate increase is discovered and viscosity change is estimated. Condition for the effect validity is given. New electric field construction for real transportation system is developed. Using real hydrodynamic diagram, some appropriate pressure gains are calculated.
Robust Control of a Spatial Robot Using Sliding Modes
Authors: Yagiz Nurkan
Published: June 2016

In this work the control of a spatial robot by sliding mode control is studied. The robot model has three degrees of freedom. These robots are usually used in material handling in remote dangerous environments and production line. First, the mathematical model of the system is formulated. The equations of motion are driven by employing Lagrangian formulation based on the energy equations. Then the sliding mode control theory is applied. Special care is given to the chattering problem. The chattering may have serious damaging effect on gear systems as well as motor drive systems. Hence, the chattering character of classical sliding mode control is overcome and a new version of the control method is applied on robot. The simulation results are presented in graphical form and the robust character of the selected control method is shown to be capable of controlling the robots successfully against the disturbances as well as having the robot follow the desired trajectory.
Some Properties of Ruled Surfaces under Homothety in E3
Authors: Kasap Emin , Yüce Salim , Kuruoğlu Nuri
Published: June 2016

It is clearly that, If f : E3→E3 is a homothety and \(\varphi\) is a surface in three dimensional Euclidean space E3, \(f(\varphi) = \overline{\varphi}\) is also a surface in E3. In this paper, the surface \(\varphi\) has been taken a ruled surface, specially. It was shown that image surface \(f(\varphi) = \overline{\varphi}\) has been a ruled surface, too. Furthermore, It was investigated whether some properties related with ruled surfaces on \(\varphi\) have been invariant under the homothety f or not.
A Mathematical Model for The Separation of Viscous Liquid Flow by Magnetic Field
Authors: Hassanov Hikmet
Published: June 2016

Inverse problem of the two - phase liquid flow separation on components under magnetic field action is firstly resolved at given law of the moving boundary alteration. Automodel solution is established, which may be approximated till various areas of dimensionless variable O. It is found the relationship between the phase radius r o and magnetic properties of the liquid involved. The dependence of velocity function on rheological parameters of the liquid is estimated. The changes of the liquid flow separation due to effect of the alternating magnetic field are shown. It is established, what liquids should be combined in total flow in order to acquire the best effect of separation.
On the Buckling Analysis of Plates Reinforced with Stiff Ribs
Authors: Akbulut Hamit , Gündoğdu Ömer
Published: June 2016

This paper deals with analytical buckling analysis of the rectangular orthotropic simply supported plates reinforced with longitudinal stiff ribs. It was considered that the ribs with rectangular and circular cross-sections were parallel and equivalent to each other. It was further assumed that the ribs were rigidly fastened to the plate and that their cross sections were perpendicular to the undeformed middle surface of the plate. These reinforced plates were subjected to the uniaxial uniform distributed compressive loads. In the study, the effect of the numbers and the cross-sections of the ribs on the buckling load were investigated. The results are striking in that how the ribs effect the isotropic plates with low strength.
Approximate First Integrals of a Hamiltonian System with Two-Degrees of Freedom
Authors: Ünal Gazanfer
Published: June 2016

Approximate Noether symmetries of a Hamiltonian system with two-degrees of freedom have been determined by incorporating the resonances. Approximate first integrals corresponding to these symmetries have been obtained by utilizing the approximate. version of the Noether’s theorem. Analytically obtained result has been compared with the numerically obtained Poincaré’s surface of sections.
Prediction of Ratio of Mineral Substitution in the Production of Low-Clinker Factored Cement by Artificial Neural Network
Authors: Canpolat Fethullah , Yilmaz Kemalettin , Ata Raşit , Köse M.
Published: June 2016

Artificial Neural Networks (ANN) has been widely used to solve some of the problems in science and engineering, which requires experimental analysis. Use of ANN in civil engineering applications started in late eighties. One of the important features of the ANN is its ability to learn from experience and examples and then to adapt with changing situations. Engineers often deal with incomplete and noisy data, which is one of the areas where ANN can easily be applied. Dealing with incomplete and noisy data is the conceptual stage of the design process. This paper shows practical guidelines for designing ANN for civil engineering applications. ANN is in cement industry: in the production of low-clinker factored cement, and in the derivation of composition of natural and artificial puzzolans in the production of high performance cement and concrete. By using ANN, a study to find out the optimum ratio of substitution and compression strengths was carried out.
Numerical Simulations of Flow Distribution in Unpacked and Partially Packed Vessels
Authors: Zughbi Habib , Sheikh Saiffudin
Published: June 2016

In this study, flow in an unpacked and a partially packed vessels is investigated using numerical simulations. The effects of various factors including the number of inlets and outlets, and throttling the jets by inserting orifice plates above them on the flow fields are investigated. Other factors investigated include fluid flow rate and turbulence model. ft was found that for a given number and location inlets and outlets, the injection velocity does not have a very significant impact on the flow distribution, This distribution could be improved with a careful choice of the number and location of inlets and outlets. For partially packed vessels, the packing may behave like a good distributor depending on the resistance to flow offered by the bed.
A Note on Mellin Transform and Distributions
Authors: Kiliçman Adem
Published: June 2016

Mellin Transform occurs in many branches of Applied Mathematics and Engineering. The Mellin transform is very much related to the Laplace and Fourier transforms and the theory for the ordinary functions is well established. In the distributional sense, first it was studied by Zemanian in [2]. In this work we try to extend to the wider class of distributions.
Presentations for Regular Unbranched Cp-Coverings of a Klein Bottle
Authors: Kazaz M.
Published: June 2016

In this paper, we obtain presentations for the non-equivalent regular unbranched Cp-coverings of a Klein Bottle by using the Reidemeister-Schreier method, where Cp =< a | ap =1 > is a cyclic group of order p (p is a prime).
Free Vibration Analysis of Elastic Beams Using Harmonic Differential Quadraure (HDQ)
Authors: Civalek Ömer , Ülker Mehmet
Published: June 2016

Harmonic differential quadrature method is developed for the free vibration analysis of linear elastic beams. In the method of differential quadrature, partial space derivatives of a function appearing in a differential equation are approximated by means of a polynomial expressed as the weighted linear sum of the function values at a preselected grid of discrete points. The weighting coefficients are treated as the unknowns. Applying this concept to the governing differential equation of beam gives a set of linear simultaneous equations, which are solved for the unknown weighting coefftcients by accounting for the boundary conditions. Beams of different support combinations such as clamped, simply supported, guided, and free are selected to demonstrate the accuracy of the method. Flexural vibration case is taken into consideration. First two frequencies are obtained in the applications. Numerical results are presented to illustrate the method and demonstrate its efficiency.
Estimation of Efficiency and Infinitesimals in Data Envelopment Analysis
Authors: Jahanshahloo G. , Hosseinzadeh Lotfi F. , Zohrehbandian M.
Published: June 2016

The role of the non-Archimedean construct ε in the DEA models is clarified. It is established that the multiplier (envelopment) forms of DEA models can be infeasible (unbounded). Sufficient conditions are established for feasibility (bounded ness) of multiplier (envelopment) forms of DEA models and a method of securing a global assurance interval for ε is provided.
A Feature Based Parametric Design Program and Expert System for Design
Authors: Başak Hüdayim , Gülesin Mahmut
Published: June 2016

In this study, a feature based parametric design program including manufacturing features which are used in machining of prismatic parts by chip removal methods has been developed. Prismatic parts modelled in the feature based system can be modified parametrically by the developed parametric design module. To modify the part model parametrically enables feature based modelling process to be flexible and easy In the developed program. the features which are added to the models prepared by a feature based design program are evaluated by the expert system module and They are used in part modelling after determining of their compatibilty according to the rules. The aim of this study is to model the manufacturing features such as a pocket, slot and hole that are used in machining operations by adding to prismatic parts, to enable the modification of the part model parametrically and to warn, inform and guide the user for design and manufacturing mistakes. The system has been developed in AutoCAD using AutoLISP language.
On the Properties of (k+1)-Dimensional Time-Like Ruled Surfaces with the Space like Generating Space in the Minkowski Space IR1n
Authors: Can S. , Uyar B. , Aydemir İ.
Published: June 2016

The purpose of this paper is to introduce a summary of known results and the definition of the time-like ruled surface with the space-like generating space in the Minkowski space IR1n, and to present some characteristic results related with minimality and total developability of the ruled surface in the n-dimensional Minkowski space IR1n.
Modeling the Torque and Power Requirements of Traction Tires of Horticultural Tractors using Dimensional Analysis
Authors: Tarhan Sefa , Çarman Kazim
Published: June 2016

The development of computational tools will promote the design and use of more energy-efficient tires. Two mathematical equations were developed by dimensional analysis to predict the torque and power requirements at zero net traction for traction fires (6.5-12; 7.00-18) on a hard surface. Some structural and working parameters of fire that affect the torque requirement, such as tire size, tire deflection, tire load, and rolling radius, were considered for the analysis. Experiments were conducted to study the effect of different wheel sizes and system parameters on torque and energy consumed per unit distance traveled in a soil bin. The ratio of tire width over fire diameter and the ratio of tire deflection over tire section height were found to be dimensionless terms radically controlling the torque and energy requirements of tires. The prediction equation closely followed the experimental results.
Detection of Volatile Metabolites of Garlic in Human Breast Milk
Authors: Scheffler Laura , Sauermann Yvonne , Zeh Gina , Hauf Katharina , Heinlein Anja , Sharapa Constanze , Buettner Andrea
Published: June 2016

The odor of human breast milk after ingestion of raw garlic at food-relevant concentrations by breastfeeding mothers was investigated for the first time chemo-analytically using gas chromatography−mass spectrometry/olfactometry (GC-MS/O), as well as sensorially using a trained human sensory panel. Sensory evaluation revealed a clear garlic/cabbage-like odor that appeared in breast milk about 2.5 h after consumption of garlic. GC-MS/O analyses confirmed the occurrence of garlic-derived metabolites in breast milk, namely allyl methyl sulfide (AMS), allyl methyl sulfoxide (AMSO) and allyl methyl sulfone (AMSO2). Of these, only AMS had a garlic-like odor whereas the other two metabolites were odorless. This demonstrates that the odor change in human milk is not related to a direct transfer of garlic odorants, as is currently believed, but rather derives from a single metabolite. The formation of these metabolites is not fully understood, but AMSO and AMSO2 are most likely formed by the oxidation of AMS in the human body. The excretion rates of these metabolites into breast milk were strongly time-dependent with large inter-individual differences.
The Influence of Modified Silica Nanomaterials on Adult Stem Cell Culture
Authors: Tarpani Luigi , Morena Francesco , Gambucci Marta , Zampini Giulia , Massaro Giuseppina , Argentati Chiara , Emiliani Carla , Martino Sabata , Latterini Loredana
Published: June 2016

The preparation of tailored nanomaterials able to support cell growth and viability is mandatory for tissue engineering applications. In the present work, silica nanoparticles were prepared by a sol-gel procedure and were then functionalized by condensation of amino groups and by adsorption of silver nanoparticles. Transmission electron microscopy (TEM) imaging was used to establish the morphology and the average dimensions of about 130 nm, which were not affected by the functionalization. The three silica samples were deposited (1 mg/mL) on cover glasses, which were used as a substrate to culture adult human bone marrow-mesenchymal stem cells (hBM-MSCs) and human adipose-derived stem cells (hASCs). The good cell viability over the different silica surfaces was evaluated by monitoring the mitochondrial dehydrogenase activity. The analysis of the morphological parameters (aspect ratio, cell length, and nuclear shape Index) yielded information about the interactions of stem cells with the surface of three different nanoparticles. The data are discussed in terms of chemical properties of the surface of silica nanoparticles.
Engineered Nanomaterials in the Environment
Authors: Judy Jonathan , Bertsch Paul
Published: June 2016

This Special Issue of Nanomaterials, “Engineered Nanomaterials in the Environment”, is comprised of one communication and ﬁve research articles.[...]
Influence of Polyplex Formation on the Performance of Star-Shaped Polycationic Transfection Agents for Mammalian Cells
Authors: Raup Alexander , Stahlschmidt Ullrich , Jérôme Valérie , Synatschke Christopher , Müller Axel , Freitag Ruth
Published: June 2016

Genetic modification (“transfection”) of mammalian cells using non-viral, synthetic agents such as polycations, is still a challenge. Polyplex formation between the DNA and the polycation is a decisive step in such experiments. Star-shaped polycations have been proposed as superior transfection agents, yet have never before been compared side-by-side, e.g., in view of structural effects. Herein four star-shaped polycationic structures, all based on (2-dimethylamino) ethyl methacrylate (DMAEMA) building blocks, were investigated for their potential to deliver DNA to adherent (CHO, L929, HEK-293) and non-adherent (Jurkat, primary human T lymphocytes) mammalian cells. The investigated vectors included three structures where the PDMAEMA arms (different arm length and grafting densities) had been grown from a center silsesquioxane or silica-coated γ-Fe2O3-core and one micellar structure self-assembled from poly(1,2-butadiene)-block PDMAEMA polymers. All nano-stars combined high transfection potential with excellent biocompatibility. The micelles slightly outperformed the covalently linked agents. For method development and optimization, the absolute amount of polycation added to the cells was more important than the N/P-ratio (ratio between polycation nitrogen and DNA phosphate), provided a lower limit was passed and enough polycation was present to overcompensate the negative charge of the plasmid DNA. Finally, the matrix (NaCl vs. HEPES-buffered glucose solution), but also the concentrations adjusted during polyplex formation, affected the results.
Distinguishing Land Change from Natural Variability and Uncertainty in Central Mexico with MODIS EVI, TRMM Precipitation, and MODIS LST Data
Authors: Christman Zachary , Rogan John , Eastman J. , Turner B.
Published: June 2016

Precipitation and temperature enact variable influences on vegetation, impacting the type and condition of land cover, as well as the assessment of change over broad landscapes. Separating the influence of vegetative variability independent and discrete land cover change remains a major challenge to landscape change assessments. The heterogeneous Lerma-Chapala-Santiago watershed of central Mexico exemplifies both natural and anthropogenic forces enacting variability and change on the landscape. This study employed a time series of Enhanced Vegetation Index (EVI) composites from the Moderate Resolution Imaging Spectoradiometer (MODIS) for 2001–2007 and per-pixel multiple linear regressions in order to model changes in EVI as a function of precipitation, temperature, and elevation. Over the seven-year period, 59.1% of the variability in EVI was explained by variability in the independent variables, with highest model performance among changing and heterogeneous land cover types, while intact forest cover demonstrated the greatest resistance to changes in temperature and precipitation. Model results were compared to an independent change uncertainty assessment, and selected regional samples of change confusion and natural variability give insight to common problems afflicting land change analyses.
Homogeneous Biosensing Based on Magnetic Particle Labels
Authors: Schrittwieser Stefan , Pelaz Beatriz , Parak Wolfgang , Lentijo-Mozo Sergio , Soulantica Katerina , Dieckhoff Jan , Ludwig Frank , Guenther Annegret , Tschöpe Andreas , Schotter Joerg
Published: June 2016

The growing availability of biomarker panels for molecular diagnostics is leading to an increasing need for fast and sensitive biosensing technologies that are applicable to point-of-care testing. In that regard, homogeneous measurement principles are especially relevant as they usually do not require extensive sample preparation procedures, thus reducing the total analysis time and maximizing ease-of-use. In this review, we focus on homogeneous biosensors for the in vitro detection of biomarkers. Within this broad range of biosensors, we concentrate on methods that apply magnetic particle labels. The advantage of such methods lies in the added possibility to manipulate the particle labels by applied magnetic fields, which can be exploited, for example, to decrease incubation times or to enhance the signal-to-noise-ratio of the measurement signal by applying frequency-selective detection. In our review, we discriminate the corresponding methods based on the nature of the acquired measurement signal, which can either be based on magnetic or optical detection. The underlying measurement principles of the different techniques are discussed, and biosensing examples for all techniques are reported, thereby demonstrating the broad applicability of homogeneous in vitro biosensing based on magnetic particle label actuation.
The Multiscale Fluctuations of the Correlation between Oil Price and Wind Energy Stock
Authors: Huang Shupei , An Haizhong , Gao Xiangyun , Jiang Meihui
Published: June 2016

Wind energy is considered a clear and sustainable substitution for fossil fuel, and the stock index of the wind energy industry is closely related to the oil price fluctuation. Their relationship is characterized by multiscale and time-varying features based on a variety of stakeholders who have different objectives within various time horizons, which makes it difficult to identify the factor in which time scale could be the most influential one in the market. Aiming to explore the correlation between oil price and the wind energy stock index from the time–frequency domain in a dynamic perspective, we propose an algorithm combining the wavelet transform, complex network, and gray correlation analyses and choose the Brent oil price and the international securities exchange (ISE) global wind energy index from January 2006 to October 2015 in daily frequency as data sample. First, we define the multiscale conformation by a set of fluctuation information with different time horizons to represent the fluctuation status of the correlation of the oil–wind nexus rather than by a single original correlation value. Then, we transform the multiscale conformation evolution into a network model, and only 270 multiscale conformations and 710 transmissions could characterize 2451 data points. We find that only 30% of conformations and transmissions work as a backbone of the entire correlation series; through these major conformations, we identify that the main factor that could influence the oil–wind nexus are long-term components, such as policies, the status of the global economy and demand–supply issues. In addition, there is a clustering effect and transmissions among conformations that mainly happen inside clusters and rarely among clusters, which means the interaction of the oil–wind nexus is stable over a short period of time.
Experience with LEDS and NAMA Low Carbon Strategies: The Case of Georgia
Authors: Mdivani Kakhaberi , Hoppe Thomas
Published: June 2016

Low Emission Development Strategies (LEDS) and National Appropriate Mitigation Actions (NAMAs) have the potential to support developing countries in attaining low carbon goals. In spite of the evident potential, there is a need to learn from practice. This paper explores the case of Georgia. The main research question discussed is: What experience has been gained with the development of LEDS and NAMAs in Georgia? The study reveals that both LEDS and NAMAs are subject to barriers that considerably slow development processes: there is a lack of institutional capacity, little inter-governmental goal alignment and poor coordination of actions, a lack of experienced staff and insufficient, substantial, earmarked funding. Capacity building depends on support from organizations in donor countries. This paper contributes to a growing body of knowledge of the implementation of LEDS and NAMA.
Is qPCR a Reliable Indicator of Cyanotoxin Risk in Freshwater?
Authors: Pacheco Ana , Guedes Iame , Azevedo Sandra
Published: June 2016

The wide distribution of cyanobacteria in aquatic environments leads to the risk of water contamination by cyanotoxins, which generate environmental and public health issues. Measurements of cell densities or pigment contents allow both the early detection of cellular growth and bloom monitoring, but these methods are not sufficiently accurate to predict actual cyanobacterial risk. To quantify cyanotoxins, analytical methods are considered the gold standards, but they are laborious, expensive, time-consuming and available in a limited number of laboratories. In cyanobacterial species with toxic potential, cyanotoxin production is restricted to some strains, and blooms can contain varying proportions of both toxic and non-toxic cells, which are morphologically indistinguishable. The sequencing of cyanobacterial genomes led to the description of gene clusters responsible for cyanotoxin production, which paved the way for the use of these genes as targets for PCR and then quantitative PCR (qPCR). Thus, the quantification of cyanotoxin genes appeared as a new method for estimating the potential toxicity of blooms. This raises a question concerning whether qPCR-based methods would be a reliable indicator of toxin concentration in the environment. Here, we review studies that report the parallel detection of microcystin genes and microcystin concentrations in natural populations and also a smaller number of studies dedicated to cylindrospermopsin and saxitoxin. We discuss the possible issues associated with the contradictory findings reported to date, present methodological limitations and consider the use of qPCR as an indicator of cyanotoxin risk.
The Future of Urban Science
Authors: Smith Michael
Published: June 2016

Urban Science is a scholarly international journal which provides a platform for the exchange of theories, ideas, methods, analysis, and comparative studies of urban and regional development.[...]
Phylogenetic and Molecular Variability Studies Reveal a New Genetic Clade of Citrus leprosis virus C
Authors: Ramos-González Pedro , Chabi-Jesus Camila , Guerra-Peraza Orlene , Breton Michèle , Arena Gabriella , Nunes Maria , Kitajima Elliot , Machado Marcos , Freitas-Astúa Juliana
Published: June 2016

Citrus leprosis virus C (CiLV-C) causes a severe disease affecting citrus orchards in the Western hemisphere. This study reveals the molecular variability of the virus by analyzing four genomic regions (p29, p15, MP and RNA2-intergenic region) distributed over its two RNAs. Nucleotide diversity (π) values were relatively low but statistically different over the analyzed genes and subpopulations, indicating their distinct evolutionary history. Values of πp29 and πMP were higher than those of πp15 and πRNA2–IR, whereas πMP was increased due to novel discovered isolates phylogenetically clustered in a divergent clade that we called SJP. Isolate BR_SP_SJP_01 RNA1 and RNA2 sequences, clade SJP, showed an identity of 85.6% and 88.4%, respectively, with those corresponding to CiLV-C, the type member of the genus Cilevirus, and its RNA2 5′-proximal region was revealed as a minor donor in a putative inter-clade recombination event. In addition to citrus, BR_SP_SJP_01 naturally infects the weed Commelina benghalensis and is efficiently transmitted by Brevipalpus yothersi mites. Our data demonstrated that negative selection was the major force operating in the evaluated viral coding regions and defined amino acids putatively relevant for the biological function of cilevirus proteins. This work provides molecular tools and sets up a framework for further epidemiological studies.
Antiviral Effects of Black Raspberry (Rubus coreanus) Seed and Its Gallic Acid against Influenza Virus Infection
Authors: Lee Ji-Hye , Oh Mi , Seok Jong , Kim Sella , Lee Dan , Bae Garam , Bae Hae-In , Bae Seon , Hong Young-Min , Kwon Sang-Oh , Lee Dong-Hun , Song Chang-Seon , Mun Ji , Chung Mi , Kim Kyung
Published: June 2016

Influenza is a serious public health concern worldwide, as it causes significant morbidity and mortality. The emergence of drug-resistant viral strains requires new approaches for the treatment of influenza. In this study, Rubus coreanus seed (RCS) that is left over from the production of wine or juice was found to show antiviral activities against influenza type A and B viruses. Using the time-of-addition plaque assay, viral replication was almost completely abolished by simultaneous treatment with the RCS fraction of less than a 1-kDa molecular weight (RCSF1). One of the polyphenols derived from RCSF1, gallic acid (GA), identified by liquid chromatography-tandem mass spectrometry, showed inhibitory effects against both influenza type A and B viruses, albeit at relatively high concentrations. RCSF1 was bound to hemagglutinin protein, inhibited hemagglutination significantly and disrupted viral particles, whereas GA was found to only disrupt the viral particles by using transmission electron microscopy. In BALB/c mice infected with influenza virus, oral administration of RCSF1 significantly improved the survival rate and reduced the viral titers in the lungs. Our results demonstrate that RCSF1 and GA show potent and broad antiviral activity against influenza A and B type viruses and are promising sources of agents that target virus particles.
A Designed “Nested” Dimer of Cyanovirin-N Increases Antiviral Activity
Authors: Woodrum Brian , Maxwell Jason , Allen Denysia , Wilson Jennifer , Krumpe Lauren , Bobkov Andrey , Hill R. , Kibler Karen , O’Keefe Barry , Ghirlanda Giovanna
Published: June 2016

Cyanovirin-N (CV-N) is an antiviral lectin with potent activity against enveloped viruses, including HIV. The mechanism of action involves high affinity binding to mannose-rich glycans that decorate the surface of enveloped viruses. In the case of HIV, antiviral activity of CV-N is postulated to require multivalent interactions with envelope protein gp120, achieved through a pseudo-repeat of sequence that adopts two near-identical glycan-binding sites, and possibly involves a 3D-domain-swapped dimeric form of CV-N. Here, we present a covalent dimer of CV-N that increases the number of active glycan-binding sites, and we characterize its ability to recognize four glycans in solution. A CV-N variant was designed in which two native repeats were separated by the “nested” covalent insertion of two additional repeats of CV-N, resulting in four possible glycan-binding sites. The resulting Nested CV-N folds into a wild-type-like structure as assessed by circular dichroism and NMR spectroscopy, and displays high thermal stability with a Tm of 59 °C, identical to WT. All four glycan-binding domains encompassed by the sequence are functional as demonstrated by isothermal titration calorimetry, which revealed two sets of binding events to dimannose with dissociation constants Kd of 25 μM and 900 μM, assigned to domains B and B’ and domains A and A’ respectively. Nested CV-N displays a slight increase in activity when compared to WT CV-N in both an anti-HIV cellular assay and a fusion assay. This construct conserves the original binding specifityies of domain A and B, thus indicating correct fold of the two CV-N repeats. Thus, rational design can be used to increase multivalency in antiviral lectins in a controlled manner.
Stress Response and Translation Control in Rotavirus Infection
Authors: López Susana , Oceguera Alfonso , Sandoval-Jaime Carlos
Published: June 2016

The general stress and innate immune responses are closely linked and overlap at many levels. The outcomes of these responses serve to reprogram host expression patterns to prevent viral invasions. In turn, viruses counter attack these cell responses to ensure their replication. The mechanisms by which viruses attempt to control host cell responses are as varied as the number of different virus families. One of the most recurrent strategies used by viruses to control the antiviral response of the cell is to hijack the translation machinery of the host, such that viral proteins are preferentially synthesized, while the expression of the stress and antiviral responses of the cell are blocked at the translation level. Here, we will review how rotaviruses, an important agent of acute severe gastroenteritis in children, overcome the stress responses of the cell to establish a productive infectious cycle.
Assessment of Risk Due to Chemicals Transferred in a Watershed: A Case of an Aquifer Storage Transfer and Recovery Site
Authors: Ji Hyon , Lee Sang-Il
Published: June 2016

This paper presents an analysis of the potential risks of chemicals that can affect an aquifer storage transfer and recovery (ASTR) site. ASTR is a water supply system that injects surface water into an aquifer and then extracts naturally filtered groundwater. The pilot site of the ASTR supplying drinking water is located downstream of the Nakdong River in South Korea. Hazard analysis and critical control points (HACCP) was adopted to ensure suitable water quality in response to the deteriorated water quality of the Nakdong River. HACCP is a proactive management system for ensuring consistent confidence in food (or water). Hazard analysis, the first of the seven principles of HACCP, assesses physical, microbial, chemical, and radioactive hazards. This study focuses on the chemicals that are most likely to be involved in major hazardous events. Pollutant release and transfer register (PRTR) data were used to analyze potential risks of chemicals. A PRTR is a national environmental database of potentially hazardous chemicals. Potential risk analysis considers the total amount of chemicals transferred off-site for treatment or disposal. Fifty-five cities and the top 10 chemicals released in the Nakdong River basin were investigated. Potential risk was defined as a function of total transfers, the relative distance, and toxicity. The top 10 cities with high potential risks were identified, and the city with the highest potential risk turned out to be Ulju.
Théocrite et les Bacchantes
Authors: Carrière Jean
Published: June 2016

L'étude ne porte que sur quelques vers. Mais ces vers, à les lire autrement qu'on ne fait d'habitude, démarquent suffisamment une grande œuvre classique pour nous renseigner quelque peu sur son inspiration véritable, incertaine jusqu'à présent.
La poésie élégiaque de Giovanni Pontano
Authors: Nespoulous Pierre
Published: June 2016

To his tone of true sincerity, Pontano adds, in a combination of his own nature and of his culture, an imitation of the Latin poets, and particularly Catullus, whom he mentions. And his amorous declarations do not concern one mistress alone ! Taking up themes or expressions of his predecessors, he evokes the force of love, laughter and tears, the sufferings of the lover. The topics of love's madness, of paraklausithuron are typical of Horace, Tibullus, Propertius and Ovid, as are the awareness of Nature, the evocation of the fountain, of the tree, of the rose, this latter leading to the brevety of life and the Carpe diem, an obsession with death dominating all.
Naissance d'Electre
Authors: Moreau Alain
Published: June 2016

The birth of Electra.

The origins of the myth of Electra are perhaps to be looked for in the Mesopo- tamian area. At any rate, there is no mention of that heroine in Homer. A mere name for a long time, she very progressively came in to existence in Hesoid, Xanthos, or on some vase paintings. Aischylos kept her in a passive role, as a character devoid of any heroism. On the contrary, Sophocles and Euripides brought the to its term, and with them Electra becomes a powerful and impressive, even bloodthirsty, character, worthy of her mother to whom she bears close resemblance : the heroine has achieved her full stature. Meanwhile, the gods have withdrawn into the blakground and Orestes has become a dimmer character.
Galba et Tarraco : à propos de Suétone, Galba, XII, 1
Authors: Le Roux Patrick
Published: June 2016

Galba and Tarraco : on Suetonius' Galba XII, 1.

In his French translation of Suetonius' Galba, XII, 1, H. Ailloud did not pay enough attention to the technical character of the vocabulary used by the As a result, there are errors of interpretation and the historical importance of the text is distorted. In Suetonius' work, the psychological portraits of Roman do not correspond to abstract models ; they are expressive of actual between individuals and the reality of imperial politics. This paper aims to point out the need for fruitful collaboration between philologists and historians in their search for new approaches to Roman political history.
La Byzacène méridionale au milieu du VIème siècle pC. d'après la Johannide de Corippus
Authors: Lassère Jean-Marie
Published: June 2016

Le poème de Corippus. la johannide (une épopée de 5000 hexamètres consacrée à la campagne du général byzantin Jean Troglita en Afrique de 546 à 548) est l'oeuvre d'un Africain qui connaît les paysages du sud de la Bysacène, région où l'on doit situer les opérations contre les Maures révoltés, entre lunci (Bordj Younga) et Tilibari (Remada). Quelques notations (parfois trop rapides) évoquent avec véracité et précision les vastes espaces poudreux de la steppe, les longs reliefs tabulaires, le rare tapis végétal. Le poète énumère quelques espèces d'arbres et donne une description des effets du sirocco. Il fait aussi allusion aux activités dans la : le charroi sur les routes ; le bétail (en particulier les chameaux). L'auteur également des préoccupations du moment et nous plonge dans l'atmosphère de cette guerre, où la fidélité souvent douteuse des Maures constitue le danger essentiel, Donc un témoignage important et intéressant sur le sud des steppes au milieu du VIe s. de notre ère.
La référence au veuvage dans les papyrus byzantins
Authors: Beaucamp Joëlle
Published: June 2016

De la fin du IIIe au milieu du VIIe siècle, les papyrus ne mentionnent que le féminin, au moyen des termes ? ? ?e ?a, ? ? ?a ? ?t ? ?, ? ? ?e ? ? ?sa et ? ? ?a La référence au veuvage figure dans des requêtes - comme à l'époque - pour inciter le destinataire à la bienveillance, ou bien - ce qui est neuf - dans des textes de caractère économique à propos de prestations charitables ou dans des actes notariés, des contrats, comme élément de la désignation d'une femme. Avec ces deux emplois nouveaux, nous n'avons pas affaire à une simple marque « d'état civil », mais il s'agit soit de justifier une aumône soit de marquer la pleine capacité de la veuve, qui échappe à la tutelle maritale.
Les transformations du mythe dans l'Hélène d'Euripide
Authors: Assaël Jacqueline
Published: June 2016

Euripide transforme complètement la légende d'Hélène que l'on connaît d'après les poèmes homériques. Il introduit dans sa pièce un double fantomatique du personnage et il crée ainsi une atmosphère de fantastique. Il inverse d'autre part la valeur de tous les éléments qui composent la légende traditionnelle et il construit un drame volontairement contradictoire par rapport à la version connue. Aucun récit mythique ou dramatique n'apparaît plus désormais crédible. Le poète ébranle toutes les certitudes. Au-delà de la contestation des mythes, sa technique théâtrale semble remettre en cause toute possibilité de connaissance. Euripide transpose, dans le domaine du théâtre, une réflexion philosophique dont on retrouve les thèmes dans la pensée grecque de son époque.
Diane, Hercule et les Convenae
Authors: Carabia Jacqueline
Published: June 2016

En 1961, on découvrit à Öhringen (Vicus Aurelius), sur le limes de Germanie Supérieure, quatre autels mutilés dont deux consacrés à Diane et à Hercule, en l'honneur de la maison divine. Tous deux datés du 13 décembre 232, furent élevés par le collegium convenarum, collège totalement inconnu. Ce collège réunissait peut-être des soldats originaires de Lugdunum Convenarum (Aquitaine) ou des hommes de diverses origines : civils et militaires, jeunes et vétérans, habitants des deux Castella d'Öhringen. En 232, le danger barbare menace le limes, il justifie l'appel à Hercule, ancêtre légendaire d'Alexandre de Macédoine dont Sévère-Alexandre se réclamait. L'érection de ces deux autels s'inscrit dans le contexte général de renouveau de religiosité et de loyalisme à l'égard du prince.
Les combats de coq furent-ils un sport ?
Authors: Dumont Jacques
Published: June 2016

"Was cock-fighting a sport ?" .

In Greece the cock was a bird recently imported from India via Persia in the 6th century BC. Stripped of its exotic allurement and a good deal of its sacredness it was soon to be used as a lover's gift and a plaything. The Greeks insisted on reading into cockfighting a real agôn on the pattern of heroic contests, while it was only a ludus , a game determined by the bird's instincts and the very peculiar biological structure of its eye : double fovea. The game may have been a way to compensate for the loss of military power in Athens, but, despite Elian's anecdote, it never was a noble activity. In a like spirit, the Greeks long opposed any gladiatorial fight on their soil.
Les religions orientales, troisième époque
Authors: Pailler Jean-Marie
Published: June 2016

Les religions orientales dans l'Empire romain connaîtront-elles une "troisième époque" ? Inventé au début de ce siècle, ce concept a eu son heure de gloire avec les études de Franz Cumont : on situait alors ce phénomène, perçu comme unitaire, au cœur de l'évolution de l'Empire s'ouvrant aux influences de l'Orient, et bientôt du christianisme. Les malheurs du IIIe siècle auraient tourné les esprits inquiets vers ces croyances nouvelles. De 1960 à sa mort récente, M.J. Vermaseren a consacré plus de cent volumes des "E.P.R.O." à un travail international d'information et de réflexion sur cette question. Aujourd'hui on dispose d'un Corpus épigraphique, textuel, iconographique pour chaque divinité, mais les problèmes de fond restent posés : - celui de l'unité du phénomène ; - celui du poids relatif des religions orientales et d'un paganisme classique resté en fait bien vivant ; - celui de l'iconographie de dieux comme Sabazios, ou du succès de Cybèle en Gaule. Et quelle place accorder aux religions orientales dans l'évolution vers "l'Antiquité tardive" ?