WorldWideScience

Sample records for aperiodic blue variables

  1. PERIODIC AND APERIODIC VARIABILITY IN THE MOLECULAR CLOUD ρ OPHIUCHUS

    International Nuclear Information System (INIS)

    Parks, J. Robert; Plavchan, Peter; Gee, Alan H.; White, Russel J.

    2014-01-01

    Presented are the results of a near-IR photometric survey of 1678 stars in the direction of the ρ Ophiuchus (ρ Oph) star forming region using data from the 2MASS Calibration Database. For each target in this sample, up to 1584 individual J-, H-, and K s -band photometric measurements with a cadence of ∼1 day are obtained over three observing seasons spanning ∼2.5 yr; it is the most intensive survey of stars in this region to date. This survey identifies 101 variable stars with ΔK s -band amplitudes from 0.044 to 2.31 mag and Δ(J – K s ) color amplitudes ranging from 0.053 to 1.47 mag. Of the 72 young ρ Oph star cluster members included in this survey, 79% are variable; in addition, 22 variable stars are identified as candidate members. Based on the temporal behavior of the K s time-series, the variability is distinguished as either periodic, long time-scale or irregular. This temporal behavior coupled with the behavior of stellar colors is used to assign a dominant variability mechanism. A new period-searching algorithm finds periodic signals in 32 variable stars with periods between 0.49 to 92 days. The chief mechanism driving the periodic variability for 18 stars is rotational modulation of cool starspots while 3 periodically vary due to accretion-induced hot spots. The time-series for six variable stars contains discrete periodic ''eclipse-like'' features with periods ranging from 3 to 8 days. These features may be asymmetries in the circumstellar disk, potentially sustained or driven by a proto-planet at or near the co-rotation radius. Aperiodic, long time-scale variations in stellar flux are identified in the time-series for 31 variable stars with time-scales ranging from 64 to 790 days. The chief mechanism driving long time-scale variability is variable extinction or mass accretion rates. The majority of the variable stars (40) exhibit sporadic, aperiodic variability over no discernable time-scale. No chief variability mechanism

  2. PERIODIC AND APERIODIC VARIABILITY IN THE MOLECULAR CLOUD ρ OPHIUCHUS

    Energy Technology Data Exchange (ETDEWEB)

    Parks, J. Robert; Plavchan, Peter; Gee, Alan H. [Infrared Processing and Analysis Center, California Institute of Technology, Mail Code 100-22, 770 South Wilson Avenue, Pasadena, CA 91125 (United States); White, Russel J., E-mail: parksj@chara.gsu.edu [Georgia State University, Department of Physics and Astronomy, 25 Park Place, Room 605, Atlanta, GA 30303 (United States)

    2014-03-01

    Presented are the results of a near-IR photometric survey of 1678 stars in the direction of the ρ Ophiuchus (ρ Oph) star forming region using data from the 2MASS Calibration Database. For each target in this sample, up to 1584 individual J-, H-, and K{sub s} -band photometric measurements with a cadence of ∼1 day are obtained over three observing seasons spanning ∼2.5 yr; it is the most intensive survey of stars in this region to date. This survey identifies 101 variable stars with ΔK{sub s} -band amplitudes from 0.044 to 2.31 mag and Δ(J – K{sub s} ) color amplitudes ranging from 0.053 to 1.47 mag. Of the 72 young ρ Oph star cluster members included in this survey, 79% are variable; in addition, 22 variable stars are identified as candidate members. Based on the temporal behavior of the K{sub s} time-series, the variability is distinguished as either periodic, long time-scale or irregular. This temporal behavior coupled with the behavior of stellar colors is used to assign a dominant variability mechanism. A new period-searching algorithm finds periodic signals in 32 variable stars with periods between 0.49 to 92 days. The chief mechanism driving the periodic variability for 18 stars is rotational modulation of cool starspots while 3 periodically vary due to accretion-induced hot spots. The time-series for six variable stars contains discrete periodic ''eclipse-like'' features with periods ranging from 3 to 8 days. These features may be asymmetries in the circumstellar disk, potentially sustained or driven by a proto-planet at or near the co-rotation radius. Aperiodic, long time-scale variations in stellar flux are identified in the time-series for 31 variable stars with time-scales ranging from 64 to 790 days. The chief mechanism driving long time-scale variability is variable extinction or mass accretion rates. The majority of the variable stars (40) exhibit sporadic, aperiodic variability over no discernable time-scale. No chief

  3. SIMULATED PERFORMANCE OF TIMESCALE METRICS FOR APERIODIC LIGHT CURVES

    Energy Technology Data Exchange (ETDEWEB)

    Findeisen, Krzysztof; Hillenbrand, Lynne [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, MC 249-17, Pasadena, CA 91125 (United States); Cody, Ann Marie, E-mail: krzys@astro.caltech.edu [Spitzer Science Center, California Institute of Technology, MC 314-6, Pasadena, CA 91125 (United States)

    2015-01-10

    Aperiodic variability is a characteristic feature of young stars, massive stars, and active galactic nuclei. With the recent proliferation of time-domain surveys, it is increasingly essential to develop methods to quantify and analyze aperiodic variability. We develop three timescale metrics that have been little used in astronomy—Δm-Δt plots, peak-finding, and Gaussian process regression—and present simulations comparing their effectiveness across a range of aperiodic light curve shapes, characteristic timescales, observing cadences, and signal to noise ratios. We find that Gaussian process regression is easily confused by noise and by irregular sampling, even when the model being fit reflects the process underlying the light curve, but that Δm-Δt plots and peak-finding can coarsely characterize timescales across a broad region of parameter space. We make public the software we used for our simulations, both in the spirit of open research and to allow others to carry out analogous simulations for their own observing programs.

  4. SIMULATED PERFORMANCE OF TIMESCALE METRICS FOR APERIODIC LIGHT CURVES

    International Nuclear Information System (INIS)

    Findeisen, Krzysztof; Hillenbrand, Lynne; Cody, Ann Marie

    2015-01-01

    Aperiodic variability is a characteristic feature of young stars, massive stars, and active galactic nuclei. With the recent proliferation of time-domain surveys, it is increasingly essential to develop methods to quantify and analyze aperiodic variability. We develop three timescale metrics that have been little used in astronomy—Δm-Δt plots, peak-finding, and Gaussian process regression—and present simulations comparing their effectiveness across a range of aperiodic light curve shapes, characteristic timescales, observing cadences, and signal to noise ratios. We find that Gaussian process regression is easily confused by noise and by irregular sampling, even when the model being fit reflects the process underlying the light curve, but that Δm-Δt plots and peak-finding can coarsely characterize timescales across a broad region of parameter space. We make public the software we used for our simulations, both in the spirit of open research and to allow others to carry out analogous simulations for their own observing programs

  5. Aperiodic-metamaterial-based absorber

    Directory of Open Access Journals (Sweden)

    Quanlong Yang

    2017-09-01

    Full Text Available The periodic-metamaterial-based perfect absorber has been studied broadly. Conversely, if the unit cell in the metamaterial-based absorber is arranged aperiodically (aperiodic-metamaterial-based absorber, how does it perform? Inspired by this, here we present a systematic study of the aperiodic-metamaterial-based absorber. By investigating the response of metamaterial absorbers based on periodic, Fibonacci, Thue-Morse, and quasicrystal lattices, we found that aperiodic-metamaterial-based absorbers could display similar absorption behaviors as the periodic one in one hand. However, their absorption behaviors show different tendency depending on the thicknesses of the spacer. Further studies on the angle and polarization dependence of the absorption behavior are also presented.

  6. PREFACE: 6th International Conference on Aperiodic Crystals (APERIODIC'09)

    Science.gov (United States)

    Grimm, Uwe; McGrath, Rónán; Degtyareva, Olga; Sharma, Hem Raj

    2010-04-01

    Aperiodic Logo Aperiodic'09, the sixth International Conference on Aperiodic Crystals, took place in Liverpool 13-18 September 2009. It was the first major conference in this interdisciplinary research field held in the UK. The conference, which was organised under the auspices of the Commission on Aperiodic Crystals of the International Union of Crystallography (IUCr), followed on from Aperiodic'94 (Les Diablerets, Switzerland), Aperiodic'97 (Alpe d'Huez, France), Aperiodic'2000 (Nijmegen, The Netherlands), Aperiodic'03 (Belo Horizonte, Brazil) and Aperiodic'06 (Zao, Japan). The next conference in the series will take place in Australia in 2012. The Aperiodic conference series is itself the successor to a series of Conferences on Modulated Structures, Polytypes and Quasicrystals (MOSPOQ), which were held in Marseilles (France) in 1984, Wroclaw (Poland) in 1986, Varanasi (India) in 1988 and Balatonszeplak (Hungary) in 1991. The remit of the conference covers two broad areas of research on aperiodic crystals, incommensurately modulated and composite crystals on the one hand, and quasicrystals on the other hand, sharing the property that they are aperiodically ordered solids. In addition, the conference also featured recent research on complex metal alloys, which are in fact periodically ordered solids. However, the term complex refers to their large unit cells, which may contain thousands of atoms, and as a consequence complex metal alloys share some of the properties of quasicrystalline solids. Aperiodic'09 attracted about 110 participants from across the world, including 20 UK-based scientists (the second largest group after Japan who sent 21 delegates). A particular feature of the conference series is its interdisciplinary character, and once again the range of disciplines of participants included mathematics, physics, crystallography and materials science. The programme started with three tutorial lectures on Sunday afternoon, presenting introductory overviews

  7. Simulation of aperiodic bipedal sprinting.

    Science.gov (United States)

    Celik, Huseyin; Piazza, Stephen J

    2013-08-01

    Synthesis of legged locomotion through dynamic simulation is useful for exploration of the mechanical and control variables that contribute to efficient gait. Most previous simulations have made use of periodicity constraints, a sensible choice for investigations of steady-state walking or running. Sprinting from rest, however, is aperiodic by nature and this aperiodicity is central to the goal of the movement, as performance is determined in large part by a rapid acceleration phase early in the race. The purpose of this study was to create a novel simulation of aperiodic sprinting using a modified spring-loaded inverted pendulum (SLIP) biped model. The optimal control problem was to find the set of controls that minimized the time for the model to run 20 m, and this problem was solved using a direct multiple shooting algorithm that converts the original continuous time problem into piecewise discrete subproblems. The resulting nonlinear programming problem was solved iteratively using a sequential quadratic programming method. The starting point for the optimizer was an initial guess simulation that was a slow alternating-gait "jogging" simulation developed using proportional-derivative feedback to control trunk attitude, swing leg angle, and leg retraction and extension. The optimized aperiodic sprint simulation solution yielded a substantial improvement in locomotion time over the initial guess (2.79 s versus 6.64 s). Following optimization, the model produced forward impulses at the start of the sprint that were four times greater than those of the initial guess simulation, producing more rapid acceleration. Several gait features demonstrated in the optimized sprint simulation correspond to behaviors of human sprinters: forward trunk lean at the start; straightening of the trunk during acceleration; and a dive at the finish. Optimization resulted in reduced foot contact times (0.065 s versus 0.210 s), but contact times early in the optimized

  8. Mathematics of aperiodic order

    CERN Document Server

    Lenz, Daniel; Savinien, Jean

    2015-01-01

    What is order that is not based on simple repetition, that is, periodicity? How must atoms be arranged in a material so that it diffracts like a quasicrystal? How can we describe aperiodically ordered systems mathematically? Originally triggered by the – later Nobel prize-winning – discovery of quasicrystals, the investigation of aperiodic order has since become a well-established and rapidly evolving field of mathematical research with close ties to a surprising variety of branches of mathematics and physics. This book offers an overview of the state of the art in the field of aperiodic order, presented in carefully selected authoritative surveys. It is intended for non-experts with a general background in mathematics, theoretical physics or computer science, and offers a highly accessible source of first-hand information for all those interested in this rich and exciting field. Topics covered include the mathematical theory of diffraction, the dynamical systems of tilings or Delone sets, their cohomolog...

  9. Aperiodic order

    CERN Document Server

    Grimm, Uwe

    2017-01-01

    Quasicrystals are non-periodic solids that were discovered in 1982 by Dan Shechtman, Nobel Prize Laureate in Chemistry 2011. The mathematics that underlies this discovery or that proceeded from it, known as the theory of Aperiodic Order, is the subject of this comprehensive multi-volume series. This second volume begins to develop the theory in more depth. A collection of leading experts, among them Robert V. Moody, cover various aspects of crystallography, generalising appropriately from the classical case to the setting of aperiodically ordered structures. A strong focus is placed upon almost periodicity, a central concept of crystallography that captures the coherent repetition of local motifs or patterns, and its close links to Fourier analysis. The book opens with a foreword by Jeffrey C. Lagarias on the wider mathematical perspective and closes with an epilogue on the emergence of quasicrystals, written by Peter Kramer, one of the founders of the field.

  10. Aperiodic linear networked control considering variable channel delays: application to robots coordination.

    Science.gov (United States)

    Santos, Carlos; Espinosa, Felipe; Santiso, Enrique; Mazo, Manuel

    2015-05-27

    One of the main challenges in wireless cyber-physical systems is to reduce the load of the communication channel while preserving the control performance. In this way, communication resources are liberated for other applications sharing the channel bandwidth. The main contribution of this work is the design of a remote control solution based on an aperiodic and adaptive triggering mechanism considering the current network delay of multiple robotics units. Working with the actual network delay instead of the maximum one leads to abandoning this conservative assumption, since the triggering condition is fixed depending on the current state of the network. This way, the controller manages the usage of the wireless channel in order to reduce the channel delay and to improve the availability of the communication resources. The communication standard under study is the widespread IEEE 802.11g, whose channel delay is clearly uncertain. First, the adaptive self-triggered control is validated through the TrueTime simulation tool configured for the mentioned WiFi standard. Implementation results applying the aperiodic linear control laws on four P3-DX robots are also included. Both of them demonstrate the advantage of this solution in terms of network accessing and control performance with respect to periodic and non-adaptive self-triggered alternatives.

  11. Aperiodic Linear Networked Control Considering Variable Channel Delays: Application to Robots Coordination

    Directory of Open Access Journals (Sweden)

    Carlos Santos

    2015-05-01

    Full Text Available One of the main challenges in wireless cyber-physical systems is to reduce the load of the communication channel while preserving the control performance. In this way, communication resources are liberated for other applications sharing the channel bandwidth. The main contribution of this work is the design of a remote control solution based on an aperiodic and adaptive triggering mechanism considering the current network delay of multiple robotics units. Working with the actual network delay instead of the maximum one leads to abandoning this conservative assumption, since the triggering condition is fixed depending on the current state of the network. This way, the controller manages the usage of the wireless channel in order to reduce the channel delay and to improve the availability of the communication resources. The communication standard under study is the widespread IEEE 802.11g, whose channel delay is clearly uncertain. First, the adaptive self-triggered control is validated through the TrueTime simulation tool configured for the mentioned WiFi standard. Implementation results applying the aperiodic linear control laws on four P3-DX robots are also included. Both of them demonstrate the advantage of this solution in terms of network accessing and control performance with respect to periodic and non-adaptive self-triggered alternatives.

  12. Aperiodic Volume Optics

    Science.gov (United States)

    Gerke, Tim D.

    Presented in this thesis is an investigation into aperiodic volume optical devices. The three main topics of research and discussion are the aperiodic volume optical devices that we call computer-generated volume holograms (CGVH), defects within periodic 3D photonic crystals, and non-periodic, but ordered 3D quasicrystals. The first of these devices, CGVHs, are designed and investigated numerically and experimentally. We study the performance of multi-layered amplitude computer-generated volume holograms in terms of efficiency and angular/frequency selectivity. Simulation results show that such aperiodic devices can increase diffraction efficiency relative to periodic amplitude volume holograms while maintaining angular and wavelength selectivity. CGVHs are also designed as voxelated volumes using a new projection optimization algorithm. They are investigated using a volumetric diffraction simulation and a standard 3D beam propagation technique as well as experimentally. Both simulation and experiment verify that the structures function according to their design. These represent the first diffractive structures that have the capacity for generating arbitrary transmission and reflection wave fronts and that provide the ability for multiplexing arbitrary functionality given different illumination conditions. Also investigated and discussed in this thesis are 3D photonic crystals and quasicrystals. We demonstrate that these devices can be fabricated using a femtosecond laser direct writing system that is particularly appropriate for fabrication of such arbitrary 3D structures. We also show that these devices can provide 3D partial bandgaps which could become complete bandgaps if fabricated using high index materials or by coating lower index materials with high index metals. Our fabrication method is particularly suited to the fabrication of engineered defects within the periodic or quasi-periodic systems. We demonstrate the potential for fabricating defects within

  13. Variable blue straggler stars in NGC 5466

    International Nuclear Information System (INIS)

    Harris, H.C.; Mateo, M.; Olszewski, E.W.; Nemec, J.M.

    1990-01-01

    Nine variable blue stragglers have been found in the globular cluster NGC 5466. The six dwarf Cepheids in this cluster coexist in the instability strip with other nonvariable stars. The three eclipsing binaries are among the hottest of the blue stragglers. The hypothesis is discussed that all blue stragglers in this cluster have undergone mass transfer in close binaries. Under this hypothesis, rotation and spin-down play important roles in controlling the evolution of blue stragglers in old clusters and in affecting some of their observational properties. 14 refs

  14. Combinations of response-reinforcer relations in periodic and aperiodic schedules.

    Science.gov (United States)

    Kuroda, Toshikazu; Cançado, Carlos R X; Lattal, Kennon A; Elcoro, Mirari; Dickson, Chata A; Cook, James E

    2013-03-01

    Key pecking of 4 pigeons was studied under a two-component multiple schedule in which food deliveries were arranged according to a fixed and a variable interfood interval. The percentage of response-dependent food in each component was varied, first in ascending (0, 10, 30, 70 and 100%) and then in descending orders, in successive conditions. The change in response rates was positively related to the percentage of response-dependent food in each schedule component. Across conditions, positively accelerated and linear patterns of responding occurred consistently in the fixed and variable components, respectively. These results suggest that the response-food dependency determines response rates in periodic and aperiodic schedules, and that the temporal distribution of food determines response patterns independently of the response-food dependency. Running rates, but not postfood pauses, also were positively related to the percentage of dependent food in each condition, in both fixed and variable components. Thus, the relation between overall response rate and the percentage of dependent food was mediated by responding that occurred after postfood pausing. The findings together extend previous studies wherein the dependency was either always present or absent, and increase the generality of the effects of variations in the response-food dependency from aperiodic to periodic schedules. © Society for the Experimental Analysis of Behavior.

  15. Effect of aperiodicity on the broadband reflection of silicon nanorod structures for photovoltaics.

    Science.gov (United States)

    Lin, Chenxi; Huang, Ningfeng; Povinelli, Michelle L

    2012-01-02

    We carry out a systematic numerical study of the effects of aperiodicity on silicon nanorod anti-reflection structures. We use the scattering matrix method to calculate the average reflection loss over the solar spectrum for periodic and aperiodic arrangements of nanorods. We find that aperiodicity can either improve or deteriorate the anti-reflection performance, depending on the nanorod diameter. We use a guided random-walk algorithm to design optimal aperiodic structures that exhibit lower reflection loss than both optimal periodic and random aperiodic structures.

  16. Optimal design of aperiodic, vertical silicon nanowire structures for photovoltaics.

    Science.gov (United States)

    Lin, Chenxi; Povinelli, Michelle L

    2011-09-12

    We design a partially aperiodic, vertically-aligned silicon nanowire array that maximizes photovoltaic absorption. The optimal structure is obtained using a random walk algorithm with transfer matrix method based electromagnetic forward solver. The optimal, aperiodic structure exhibits a 2.35 times enhancement in ultimate efficiency compared to its periodic counterpart. The spectral behavior mimics that of a periodic array with larger lattice constant. For our system, we find that randomly-selected, aperiodic structures invariably outperform the periodic array.

  17. Creating aperiodic photonic structures by synthesized Mathieu-Gauss beams

    Science.gov (United States)

    Vasiljević, Jadranka M.; Zannotti, Alessandro; Timotijević, Dejan V.; Denz, Cornelia; Savić, Dragana M. Jović

    2017-08-01

    We demonstrate a kind of aperiodic photonic structure realized using the interference of multiple Mathieu-Gauss beams. Depending on the beam configurations, their mutual distances, angles of rotation, or phase relations we are able to observe different classes of such aperiodic optically induced refractive index structures. Our experimental approach is based on the optical induction in a single parallel writing process.

  18. A method to identify aperiodic disturbances in the ionosphere

    Science.gov (United States)

    Wang, J.-S.; Chen, Z.; Huang, C.-M.

    2014-05-01

    In this paper, variations in the ionospheric F2 layer's critical frequency are decomposed into their periodic and aperiodic components. The latter include disturbances caused both by geophysical impacts on the ionosphere and random noise. The spectral whitening method (SWM), a signal-processing technique used in statistical estimation and/or detection, was used to identify aperiodic components in the ionosphere. The whitening algorithm adopted herein is used to divide the Fourier transform of the observed data series by a real envelope function. As a result, periodic components are suppressed and aperiodic components emerge as the dominant contributors. Application to a synthetic data set based on significant simulated periodic features of ionospheric observations containing artificial (and, hence, controllable) disturbances was used to validate the SWM for identification of aperiodic components. Although the random noise was somewhat enhanced by post-processing, the artificial disturbances could still be clearly identified. The SWM was then applied to real ionospheric observations. It was found to be more sensitive than the often-used monthly median method to identify geomagnetic effects. In addition, disturbances detected by the SWM were characterized by a Gaussian-type probability density function over all timescales, which further simplifies statistical analysis and suggests that the disturbances thus identified can be compared regardless of timescale.

  19. Thermal Emission Control via Bandgap Engineering in Aperiodically Designed Nanophotonic Devices

    Directory of Open Access Journals (Sweden)

    Enrique Maciá

    2015-05-01

    Full Text Available Aperiodic photonic crystals can open up novel routes for more efficient photon management due to increased degrees of freedom in their design along with the unique properties brought about by the long-range aperiodic order as compared to their periodic counterparts. In this work we first describe the fundamental notions underlying the idea of thermal emission/absorption control on the basis of the systematic use of aperiodic multilayer designs in photonic quasicrystals. Then, we illustrate the potential applications of this approach in order to enhance the performance of daytime radiative coolers and solar thermoelectric energy generators.

  20. Reclaiming Spare Capacity and Improving Aperiodic Response Times in Real-Time Environments

    Directory of Open Access Journals (Sweden)

    Liu Xue

    2011-01-01

    Full Text Available Abstract Scheduling recurring task sets that allow some instances of the tasks to be skipped produces holes in the schedule which are nonuniformly distributed. Similarly, when the recurring tasks are not strictly periodic but are sporadic, there is extra processor bandwidth arising because of irregular job arrivals. The additional computation capacity that results from skips or sporadic tasks can be reclaimed to service aperiodic task requests efficiently and quickly. We present techniques for improving the response times of aperiodic tasks by identifying nonuniformly distributed spare capacity—because of skips or sporadic tasks—in the schedule and adding such extra capacity to the capacity queue of a BASH server. These gaps can account for a significant portion of aperiodic capacity, and their reclamation results in considerable improvement to aperiodic response times. We present two schemes: NCLB-CBS, which performs well in periodic real-time environments with firm tasks, and NCLB-CUS, which can be deployed when the basic task set to schedule is sporadic. Evaluation via simulations and implementation suggests that performance improvements for aperiodic tasks can be obtained with limited additional overhead.

  1. Dynamical mechanisms for sensitive response of aperiodic firing cells to external stimulation

    International Nuclear Information System (INIS)

    Xie Yong; Xu Jianxue; Hu Sanjue; Kang Yanmei; Yang Hongjun; Duan Yubin

    2004-01-01

    An interesting phenomenon that aperiodic firing neurons have a higher sensitivity to drugs than periodic firing neurons have been reported for the chronically compressed dorsal root ganglion neurons in rats. In this study, the dynamical mechanisms for such a phenomenon are uncovered from the viewpoint of dynamical systems theory. We use the Rose-Hindmarsh neuron model to illustrate our opinions. Periodic orbit theory is introduced to characterize the dynamical behavior of aperiodic firing neurons. It is considered that bifurcations, crises and sensitive dependence of chaotic motions on control parameters can be the underlying mechanisms. And then, a similar analysis is applied to the modified Chay model describing the firing behavior of pancreatic beta cells. The same dynamical mechanisms can be obtained underlying that aperiodic firing cells are more sensitive to external stimulation than periodic firing ones. As a result, we conjecture that sensitive response of aperiodic firing cells to external stimulation is a universal property of excitable cells

  2. Control, synchronization, and enhanced reliability of aperiodic oscillations in the Mercury Beating Heart system

    Science.gov (United States)

    Kumar, Pawan; Parmananda, P.

    2018-04-01

    Experiments involving the Mercury Beating Heart (MBH) oscillator, exhibiting irregular (aperiodic) dynamics, are performed. In the first set of experiments, control over irregular dynamics of the MBH oscillator was obtained via a superimposed periodic voltage signal. These irregular (aperiodic) dynamics were recovered once the control was switched off. Subsequently, two MBH oscillators were coupled to attain synchronization of their aperiodic oscillations. Finally, two uncoupled MBH oscillators were subjected, repeatedly, to a common stochastic forcing, resulting in an enhancement of their mutual phase correlation.

  3. Band structures and localization properties of aperiodic layered phononic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Yan Zhizhong, E-mail: zzyan@bit.edu.cn [Department of Applied Mathematics, Beijing Institute of Technology, Beijing 100081 (China); Zhang Chuanzeng [Department of Civil Engineering, University of Siegen, D-57078 Siegen (Germany)

    2012-03-15

    The band structures and localization properties of in-plane elastic waves with coupling of longitudinal and transverse modes oblique propagating in aperiodic phononic crystals based on Thue-Morse and Rudin-Shapiro sequences are studied. Using transfer matrix method, the concept of the localization factor is introduced and the correctness is testified through the Rytov dispersion relation. For comparison, the perfect periodic structure and the quasi-periodic Fibonacci system are also considered. In addition, the influences of the random disorder, local resonance, translational and/or mirror symmetries on the band structures of the aperiodic phononic crystals are analyzed in this paper.

  4. Structural color of a lycaenid butterfly: analysis of an aperiodic multilayer structure

    International Nuclear Information System (INIS)

    Yoshioka, S; Shimizu, Y; Kinoshita, S; Matsuhana, B

    2013-01-01

    We investigated the structural color of the green wing of the lycaenid butterfly Chrysozephyrus brillantinus. Electron microscopy revealed that the bottom plate of the cover scale on the wing consists of an alternating air–cuticle multilayer structure. However, the thicknesses of the layers were not constant but greatly differed depending on the layer, unlike the periodic multilayer designs often adopted for artificial laser-reflecting mirrors. The agreement between the experimentally determined and theoretically calculated reflectance spectra led us to conclude that the multilayer interference in the aperiodic system is the primary origin of the structural color. We analyzed optical interference in this aperiodic system using a simple analytical model and found that two spectral peaks arise from constructive interference among different parts of the multilayer structure. We discuss the advantages and disadvantages of the aperiodic system over a periodic one. (paper)

  5. A 'variable' stellar object in a variable blue nebula V-V 1-7

    International Nuclear Information System (INIS)

    Rao, N.K.; Gilra, D.P.

    1981-01-01

    V-V 1-7 is supposed to be one of the few planetary nebulae with Ao central stars and was included in the planetary-nebula catalogue as PK 235 + 1 0 1. The nebula was seen on the blue Palomar Observatory Sky Survey (POSS) print but not on the red print; as a result it was thought that it might be a reflection nebula. However, the symmetry of the nebula around the central star (HD 62001), and also the ultraviolet photometric variability of this central star led others to suggest that the nebula might be a nova shell. Subsequently it was found that the nebula V-V 1-7 has disappeared. It is not seen on any direct plate known to us except the POSS blue plate. In this paper the disappearance is reported (along with the nebula) of a stellar object, which appears within the 'nebular shell' of V-V 1-7 on the POSS blue plate, but not on the red plate. (author)

  6. Aperiodicity Correction for Rotor Tip Vortex Measurements

    Science.gov (United States)

    Ramasamy, Manikandan; Paetzel, Ryan; Bhagwat, Mahendra J.

    2011-01-01

    The initial roll-up of a tip vortex trailing from a model-scale, hovering rotor was measured using particle image velocimetry. The unique feature of the measurements was that a microscope was attached to the camera to allow much higher spatial resolution than hitherto possible. This also posed some unique challenges. In particular, the existing methodologies to correct for aperiodicity in the tip vortex locations could not be easily extended to the present measurements. The difficulty stemmed from the inability to accurately determine the vortex center, which is a prerequisite for the correction procedure. A new method is proposed for determining the vortex center, as well as the vortex core properties, using a least-squares fit approach. This approach has the obvious advantage that the properties are derived from not just a few points near the vortex core, but from a much larger area of flow measurements. Results clearly demonstrate the advantage in the form of reduced variation in the estimated core properties, and also the self-consistent results obtained using three different aperiodicity correction methods.

  7. Temporal variability of green and blue water footprint worldwide

    Science.gov (United States)

    Tamea, Stefania; Lomurno, Marianna; Tuninetti, Marta; Laio, Francesco; Ridolfi, Luca

    2016-04-01

    Water footprint assessment is becoming widely used in the scientific literature and it is proving useful in a number of multidisciplinary contexts. Given this increasing popularity, measures of green and blue water footprint (or virtual water content, VWC) require evaluations of uncertainty and variability to quantify the reliability of proposed analyses. As of today, no studies are known to assess the temporal variability of crop VWC at the global scale; the present contribution aims at filling this gap. We use a global high-resolution distributed model to compute the VWC of staple crops (wheat and maize), basing on the soil water balance, forced by hydroclimatic imputs, and on the total crop evapotranspiration in multiple growing seasons. Crop actual yield is estimated using country-based yield data, adjusted to account for spatial variability, allowing for the analysis of the different role played by climatic and management factors in the definition of crop yield. The model is then run using hydroclimatic data, i.e., precipitation and potential evapotranspiration, for the period 1961-2013 as taken from the CRU database (CRU TS v. 3.23) and using the corresponding country-based yield data from FAOSTAT. Results provide the time series of total evapotranspiration, actual yield and VWC, with separation between green and blue VWC, and the overall volume of water used for crop production, both at the cell scale (5x5 arc-min) and aggregated at the country scale. Preliminary results indicate that total (green+blue) VWC is, in general, weekly dependent on hydroclimatic forcings if water for irrigation is unlimited, because irrigated agriculture allows to compensate temporary water shortage. Conversely, most part of the VWC variability is found to be determined by the temporal evolution of crop yield. At the country scale, the total water used by countries for agricultural production has seen a limited change in time, but the marked increase in the water-use efficiency

  8. Improving emission uniformity and linearizing band dispersion in nanowire arrays using quasi-aperiodicity

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, P. Duke [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Univ. of Southern California, Los Angeles, CA (United States). Ming Hsieh Dept. of Electrical Engineering; Koleske, Daniel D. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Povinelli, Michelle L. [Univ. of Southern California, Los Angeles, CA (United States). Ming Hsieh Dept. of Electrical Engineering; Subramania, Ganapathi [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

    2017-10-01

    For this study, we experimentally investigate a new class of quasi-aperiodic structures for improving the emission pattern in nanowire arrays. Efficient normal emission, as well as lasing, can be obtained from III-nitride photonic crystal (PhC) nanowire arrays that utilize slow group velocity modes near the Γ-point in reciprocal space. However, due to symmetry considerations, the emitted far-field pattern of such modes are often ‘donut’-like. Many applications, including lighting for displays or lasers, require a more uniform beam profile in the far-field. Previous work has improved far-field beam uniformity of uncoupled modes by changing the shape of the emitting structure. However, in nanowire systems, the shape of nanowires cannot always be arbitrarily changed due to growth or etch considerations. Here, we investigate breaking symmetry by instead changing the position of emitters. Using a quasi-aperiodic geometry, which changes the emitter position within a photonic crystal supercell (2x2), we are able to linearize the photonic bandstructure near the Γ-point and greatly improve emitted far-field uniformity. We realize the III-nitride nanowires structures using a top-down fabrication procedure that produces nanowires with smooth, vertical sidewalls. Comparison of room-temperature micro-photoluminescence (µ-PL) measurements between periodic and quasi-aperiodic nanowire arrays reveal resonances in each structure, with the simple periodic structure producing a donut beam in the emitted far-field and the quasi-aperiodic structure producing a uniform Gaussian-like beam. We investigate the input pump power vs. output intensity in both systems and observe the simple periodic array exhibiting a non-linear relationship, indicative of lasing. We believe that the quasi-aperiodic approach studied here provides an alternate and promising strategy for shaping the emission pattern of nanoemitter systems.

  9. An aperiodic phenomenon of the unscented Kalman filter in filtering noisy chaotic signals

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A non-periodic oscillatory behavior of the unscented Kalman filter (UKF) when used to filter noisy contaminated chaotic signals is reported. We show both theoretically and experimentally that the gain of the UKF may not converge or diverge but oscillate aperiodically. More precisely, when a nonlinear system is periodic, the Kalman gain and error covariance of the UKF converge to zero. However, when the system being considered is chaotic, the Kalman gain either converges to a fixed point with a magnitude larger than zero or oscillates aperiodically.

  10. Charge transport properties of DNA aperiodic molecule: The role of interbase hopping in Watson-Crick base pair

    Science.gov (United States)

    Sinurat, E. N.; Yudiarsah, E.

    2017-07-01

    The charge transport properties of DNA aperiodic molecule has been studied by considering various interbase hopping parameter on Watson-Crick base pair. 32 base pairs long double-stranded DNA aperiodic model with sequence GCTAGTACGTGACGTAGCTAGGATATGCCTGA on one chain and its complement on the other chain is used. Transfer matrix method has been used to calculate transmission probabilities, for determining I-V characteristic using Landauer Büttiker formula. DNA molecule is modeled using tight binding hamiltonian combined with the theory of Slater-Koster. The result show, the increment of Watson-Crick hopping value leads to the transmission probabilities and current of DNA aperiodic molecule increases.

  11. Intrinsic periodic and aperiodic stochastic resonance in an electrochemical cell

    Science.gov (United States)

    Tiwari, Ishant; Phogat, Richa; Parmananda, P.; Ocampo-Espindola, J. L.; Rivera, M.

    2016-08-01

    In this paper we show the interaction of a composite of a periodic or aperiodic signal and intrinsic electrochemical noise with the nonlinear dynamics of an electrochemical cell configured to study the corrosion of iron in an acidic media. The anodic voltage setpoint (V0) in the cell is chosen such that the anodic current (I ) exhibits excitable fixed point behavior in the absence of noise. The subthreshold periodic (aperiodic) signal consists of a train of rectangular pulses with a fixed amplitude and width, separated by regular (irregular) time intervals. The irregular time intervals chosen are of deterministic and stochastic origins. The amplitude of the intrinsic internal noise, regulated by the concentration of chloride ions, is then monotonically increased, and the provoked dynamics are analyzed. The signal to noise ratio and the cross-correlation coefficient versus the chloride ions' concentration curves have a unimodal shape indicating the emergence of an intrinsic periodic or aperiodic stochastic resonance. The abscissa for the maxima of these unimodal curves correspond to the optimum value of intrinsic noise where maximum regularity of the invoked dynamics is observed. In the particular case of the intrinsic periodic stochastic resonance, the scanning electron microscope images for the electrode metal surfaces are shown for certain values of chloride ions' concentrations. These images, qualitatively, corroborate the emergence of order as a result of the interaction between the nonlinear dynamics and the composite signal.

  12. Simulation of photonic waveguides with deterministic aperiodic nanostructures for biosensing

    DEFF Research Database (Denmark)

    Neustock, Lars Thorben; Paulsen, Moritz; Jahns, Sabrina

    2016-01-01

    Photonic waveguides with deterministic aperiodic corrugations offer rich spectral characteristics under surface-normal illumination. The finite-element method (FEM), the finite-difference time-domain (FDTD) method and a rigorous coupled wave algorithm (RCWA) are compared for computing the near...

  13. Outer synchronization of complex networks with internal delay and coupling delay via aperiodically intermittent pinning control

    Science.gov (United States)

    Zhang, Chuan; Wang, Xingyuan; Wang, Chunpeng; Xia, Zhiqiu

    This paper concerns the outer synchronization problem between two complex delayed networks via the method of aperiodically intermittent pinning control. Apart from previous works, internal delay and coupling delay are both involved in this model, and the designed intermittent controllers can be aperiodic. The main work in this paper can be summarized as follows: First, two cases of aperiodically intermittent control with constant gain and adaptive gain are implemented, respectively. The intermittent control and pinning control are combined to reduce consumptions further. Then, based on the Lyapunov stability theory, synchronization protocols are given by strict derivation. Especially, the designed controllers are indeed simple and valid in application of theory to practice. Finally, numerical examples put the proposed control methods to the test.

  14. Non-commutative Chern numbers for generic aperiodic discrete systems

    Science.gov (United States)

    Bourne, Chris; Prodan, Emil

    2018-06-01

    The search for strong topological phases in generic aperiodic materials and meta-materials is now vigorously pursued by the condensed matter physics community. In this work, we first introduce the concept of patterned resonators as a unifying theoretical framework for topological electronic, photonic, phononic etc (aperiodic) systems. We then discuss, in physical terms, the philosophy behind an operator theoretic analysis used to systematize such systems. A model calculation of the Hall conductance of a 2-dimensional amorphous lattice is given, where we present numerical evidence of its quantization in the mobility gap regime. Motivated by such facts, we then present the main result of our work, which is the extension of the Chern number formulas to Hamiltonians associated to lattices without a canonical labeling of the sites, together with index theorems that assure the quantization and stability of these Chern numbers in the mobility gap regime. Our results cover a broad range of applications, in particular, those involving quasi-crystalline, amorphous as well as synthetic (i.e. algorithmically generated) lattices.

  15. Topological aperiodicity for product systems over semigroups of Ore type

    DEFF Research Database (Denmark)

    Kwasniewski, Bartosz; Szymanski, Wojciech

    2016-01-01

    aperiodicity condition on the latter, we obtain the uniqueness theorem and a simplicity criterion for the algebras in question. These results generalize the corresponding ones for crossed products by discrete groups, due to Archbold and Spielberg, and for Exel's crossed products, due to Exel and Vershik...

  16. Blue and Orange Two-Color CW Laser Based on Single-Pass Second-Harmonic and Sum-Frequency Generation in MgO:PPLN

    Directory of Open Access Journals (Sweden)

    Dismas K. Choge

    2018-04-01

    Full Text Available We demonstrate a compact blue and orange-two color continuous wave laser source emitting at 487 nm and from 597.4 to 600.3 nm, respectively. The temperature tunable coherent orange radiation is achieved by frequency mixing 974 nm laser diode (LD and a C-band amplified spontaneous emission laser source while the temperature insensitive blue radiation is generated by second-order quasi-phase-matching frequency doubling of 974 nm LD. We implement the simultaneous nonlinear processes in a single magnesium oxide doped periodically poled lithium niobate bulk crystal without the need of an aperiodic design.

  17. Aperiodic spin state ordering of bistable molecules and its photoinducede erasing

    Czech Academy of Sciences Publication Activity Database

    Collet, E.; Watanabe, H.; Bréfuel, N.; Palatinus, Lukáš; Roudaut, L.; Toupet, L.; Tanaka, K.; Tuchagues, J.-P.; Fertey, P.; Ravy, S.; Toudic, B.; Cailleau, H.

    2012-01-01

    Roč. 109, č. 25 (2012), "257206-1"-"257206-5" ISSN 0031-9007 Institutional research plan: CEZ:AV0Z10100521 Keywords : photocrystallography * aperiodic structure * spin-state ordering Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 7.943, year: 2012

  18. Diffuse scattering from periodic and aperiodic crystals

    International Nuclear Information System (INIS)

    Frey, F.

    1997-01-01

    A (selective) review on diffuse scattering from periodic and aperiodic crystalline solids is given to demonstrate the wide field of applications in basic and applied research. After a general introduction in this field each topic is exemplified by one or two examples. Main emphasis is laid on recent work. More established work, e.g., on diffuse scattering from metals and alloys, polytypes, stacking disorder from layered structures, etc. is omitted due to the availability of excellent textbooks and reviews. Finally a short summary of recent developments of experimental methods and evaluation techniques is presented. (orig.)

  19. Near-to far-field transformation in the aperiodic Fourier modal method

    NARCIS (Netherlands)

    Rook, R.; Pisarenco, M.; Setija, I.D.

    2013-01-01

    This paper addresses the task of obtaining the far-field spectrum for a finite structure given the near-field calculated by the aperiodic Fourier modal method in contrast-field formulation (AFMM-CFF). The AFMM-CFF efficiently calculates the solution to Maxwell's equations for a finite structure by

  20. Aperiodic signals processing via parameter-tuning stochastic resonance in a photorefractive ring cavity

    Directory of Open Access Journals (Sweden)

    Xuefeng Li

    2014-04-01

    Full Text Available Based on solving numerically the generalized nonlinear Langevin equation describing the nonlinear dynamics of stochastic resonance by Fourth-order Runge-Kutta method, an aperiodic stochastic resonance based on an optical bistable system is numerically investigated. The numerical results show that a parameter-tuning stochastic resonance system can be realized by choosing the appropriate optical bistable parameters, which performs well in reconstructing aperiodic signals from a very high level of noise background. The influences of optical bistable parameters on the stochastic resonance effect are numerically analyzed via cross-correlation, and a maximum cross-correlation gain of 8 is obtained by optimizing optical bistable parameters. This provides a prospective method for reconstructing noise-hidden weak signals in all-optical signal processing systems.

  1. Wide-Area Assessment of Aperiodic Small Signal Rotor Angle Stability in Real-Time

    DEFF Research Database (Denmark)

    Jóhannsson, Hjörtur; Nielsen, Arne Hejde; Østergaard, Jacob

    2013-01-01

    This paper presents the details of a new real-time stability assessment method. The method assesses a particular mechanism of stability: each generator’s capability to generate sufficient steady state electromechanical torque. The lack of sufficient steady state torque causes aperiodic increase...... of multiple operating points is derived in the paper. Finally, results from time-domain simulation of instability scenarios in the Nordic32 test system are presented and results used for testing the assessment method. The results illustrate the method’s capability to efficiently identify the location...... in rotor angle and a loss of synchronism, referred to as aperiodic small signal instability. The paper provides the theoretical background of the method and an analytical assessment criterion. Furthermore, a mathematical mapping of the generators’ operating points that enables informative visualization...

  2. Synchronization of coupled stochastic complex-valued dynamical networks with time-varying delays via aperiodically intermittent adaptive control

    Science.gov (United States)

    Wang, Pengfei; Jin, Wei; Su, Huan

    2018-04-01

    This paper deals with the synchronization problem of a class of coupled stochastic complex-valued drive-response networks with time-varying delays via aperiodically intermittent adaptive control. Different from the previous works, the intermittent control is aperiodic and adaptive, and the restrictions on the control width and time delay are removed, which lead to a larger application scope for this control strategy. Then, based on the Lyapunov method and Kirchhoff's Matrix Tree Theorem as well as differential inequality techniques, several novel synchronization conditions are derived for the considered model. Specially, impulsive control is also considered, which can be seen as a special case of the aperiodically intermittent control when the control width tends to zero. And the corresponding synchronization criteria are given as well. As an application of the theoretical results, a class of stochastic complex-valued coupled oscillators with time-varying delays is studied, and the numerical simulations are also given to demonstrate the effectiveness of the control strategies.

  3. Two methods for studying the X-ray variability

    NARCIS (Netherlands)

    Yan, Shu-Ping; Ji, Li; Méndez, Mariano; Wang, Na; Liu, Siming; Li, Xiang-Dong

    2016-01-01

    The X-ray aperiodic variability and quasi-periodic oscillation (QPO) are the important tools to study the structure of the accretion flow of X-ray binaries. However, the origin of the complex X-ray variability from X-ray binaries remains yet unsolved. We proposed two methods for studying the X-ray

  4. Analysis of Nonlinear Periodic and Aperiodic Media: Application to Optical Logic Gates

    Science.gov (United States)

    Yu, Yisheng

    This dissertation is about the analysis of nonlinear periodic and aperiodic media and their application to the design of intensity controlled all optical logic gates: AND, OR, and NOT. A coupled nonlinear differential equation that characterizes the electromagnetic wave propagation in a nonlinear periodic (and aperiodic) medium has been derived from the first principle. The equations are general enough that it reflects the effect of transverse modal fields and can be used to analyze both co-propagating and counter propagating waves. A numerical technique based on the finite differences method and absorbing boundary condition has been developed to solve the coupled differential equations here. The numerical method is simple and accurate. Unlike the method based on characteristics that has been reported in the literature, this method does not involve integration and step sizes of time and space coordinates are decoupled. The decoupling provides independent choice for time and space step sizes. The concept of "gap soliton" has also been re-examined. The dissertation consists of four manuscripts. Manuscript I reports on the design of all optical logic gates: AND, OR, and NOT based on the bistability property of nonlinear periodic and aperiodic waveguiding structures. The functioning of the logic gates has been shown by analysis. The numerical technique that has been developed to solve the nonlinear differential equations are addressed in manuscript II. The effect of transverse modal fields on the bistable property of nonlinear periodic medium is reported in manuscript III. The concept of "gap soliton" that are generated in a nonlinear periodic medium has been re-examined. The details on the finding of the re-examination are discussed in manuscript IV.

  5. Periodic and aperiodic flow patterns around an airfoil with leading-edge protuberances

    Science.gov (United States)

    Cai, Chang; Zuo, Zhigang; Maeda, Takao; Kamada, Yasunari; Li, Qing'an; Shimamoto, Kensei; Liu, Shuhong

    2017-11-01

    Recently leading-edge protuberances have attracted great attention as a passive method for separation control. In this paper, the effect of multiple leading-edge protuberances on the performance of a two-dimensional airfoil is investigated through experimental measurement of aerodynamic forces, surface tuft visualization, and numerical simulation. In contrast to the sharp stall of the baseline airfoil with large hysteresis effect during AOA (angle of attack) increasing and decreasing, the stall process of the modified airfoil with leading-edge protuberances is gentle and stable. Flow visualization revealed that the flow past each protuberance is periodic and symmetric at small AOAs. Streamwise vortices are generated on the shoulders of the protuberance, leading to a larger separation around the valley sections and a longer attachment along the peak sections. When some critical AOA is exceeded, aperiodic and asymmetric flow patterns occur on the protuberances at different spanwise positions, with leading-edge separation on some of the valley sections and non-stalled condition elsewhere. A combined mechanism, involving both the compartmentalization effect of the slender momentum-enhanced attached flows on the protuberance peaks and the downwash effect of the local stalled region with low circulation, is proposed to explain the generation of the aperiodic flow patterns. The influence of the number of protuberances is also investigated, which shows similar aperiodic flow patterns. The distance between the neighboring local stalled valley sections is found to be in the range of 4-7 times the protuberance wavelength. According to the proposed mechanism, it is speculated that the distance between the neighboring local stalled valley sections is inclined to increase with a smaller protuberance amplitude or at a larger AOA.

  6. Wide-Area Assessment of Aperiodic Small Signal Rotor Angle Stability in Real-Time

    DEFF Research Database (Denmark)

    Jóhannsson, Hjörtur; Nielsen, Arne Hejde; Østergaard, Jacob

    2014-01-01

    in rotor angle and a loss of synchronism, referred to as aperiodic small signal instability. The paper provides the theoretical background of the method and an analytical assessment criterion. Furthermore, a mathematical mapping of the generators' operating points that enables informative visualization...

  7. Wide Area Prosumption Control and Sensitivities of Aperiodic Small Signal Stability Indicators

    DEFF Research Database (Denmark)

    Wittrock, Martin Lindholm; Jóhannsson, Hjörtur; Nielsen, Arne Hejde

    2014-01-01

    and patterns, stability indicators for aperiodic small signal angular stability (ASSA) are examined, while the concept of prosumption is described. The methodology presented is shown to be able to assess the margin to instability and to predict how this margin can be affected if a load is changed in the grid...

  8. Investigation of aperiodic W/C multi-layer mirror for X-ray optics

    International Nuclear Information System (INIS)

    Wang Zhanshan; Cheng Xinbin; Zhu Jingtao; Huang Qiushi; Zhang Zhong; Chen Lingyan

    2011-01-01

    Design, fabrication and characterization of aperiodic tungsten/carbon (W/C) multi-layer mirror were studied. W/C multi-layer was designed as a broad-angle reflective supermirror for Cu-Kα line (λ = 0.154 nm) in the grazing incident angular range (0.9-1.1 deg.) using simulated annealing algorithm. To deposit the W/C depth-graded multi-layer mirror accurately, we introduce an effective layer growth rate as a function of layer thickness. This method greatly improves the reflectivity curve compared to the conventional multi-layer mirror prepared with constant growth rate. The deposited multi-layer mirror exhibits an average reflectivity of 19% over the grazing incident angle range of 0.88-1.08 deg. which mainly coincides with the designed value. Furthermore, the physical mechanisms were discussed and the re-sputtering process of light-atom layers is accounted for the modification of layer thicknesses which leads to the effective growth rates. Using this calibration method, the aperiodic multi-layer mirrors can be better fabricated for X-ray optics.

  9. Elastic wave localization in two-dimensional phononic crystals with one-dimensional random disorder and aperiodicity

    International Nuclear Information System (INIS)

    Yan Zhizhong; Zhang Chuanzeng; Wang Yuesheng

    2011-01-01

    The band structures of in-plane elastic waves propagating in two-dimensional phononic crystals with one-dimensional random disorder and aperiodicity are analyzed in this paper. The localization of wave propagation is discussed by introducing the concept of the localization factor, which is calculated by the plane-wave-based transfer-matrix method. By treating the random disorder and aperiodicity as the deviation from the periodicity in a special way, three kinds of aperiodic phononic crystals that have normally distributed random disorder, Thue-Morse and Rudin-Shapiro sequence in one direction and translational symmetry in the other direction are considered and the band structures are characterized using localization factors. Besides, as a special case, we analyze the band gap properties of a periodic planar layered composite containing a periodic array of square inclusions. The transmission coefficients based on eigen-mode matching theory are also calculated and the results show the same behaviors as the localization factor does. In the case of random disorders, the localization degree of the normally distributed random disorder is larger than that of the uniformly distributed random disorder although the eigenstates are both localized no matter what types of random disorders, whereas, for the case of Thue-Morse and Rudin-Shapiro structures, the band structures of Thue-Morse sequence exhibit similarities with the quasi-periodic (Fibonacci) sequence not present in the results of the Rudin-Shapiro sequence.

  10. New Galactic Candidate Luminous Blue Variables and Wolf-Rayet Stars

    Science.gov (United States)

    Stringfellow, Guy S.; Gvaramadze, Vasilii V.; Beletsky, Yuri; Kniazev, Alexei Y.

    2012-04-01

    We have undertaken a near-infrared spectral survey of stars associated with compact mid-IR shells recently revealed by the MIPSGAL (24 μm) and GLIMPSE (8 μm) Spitzer surveys, whose morphologies are typical of circumstellar shells produced by massive evolved stars. Through spectral similarity with known Luminous Blue Variable (LBV) and Wolf-Rayet (WR) stars, a large population of candidate LBVs (cLBVs) and a smaller number of new WR stars are being discovered. This significantly increases the Galactic cLBV population and confirms that nebulae are inherent to most (if not all) objects of this class.

  11. Long-term spectroscopic monitoring of the Luminous Blue Variable AG Carinae

    Science.gov (United States)

    Stahl, O.; Jankovics, I.; Kovács, J.; Wolf, B.; Schmutz, W.; Kaufer, A.; Rivinius, Th.; Szeifert, Th.

    2001-08-01

    We have extensively monitored the Luminous Blue Variable AG Car (HD 94910) spectroscopically. Our data cover the years 1989 to 1999. In this period, the star underwent almost a full S Dor cycle from visual minimum to maximum and back. Over several seasons, up to four months of almost daily spectra are available. Our data cover most of the visual spectral range with a high spectral resolution (lambda /Delta lambda ~ 20 000). This allows us to investigate the variability in many lines on time scales from days to years. The strongest variability occurs on a time scale of years. Qualitatively, the variations can be understood as changes of the effective temperature and radius, which are in phase with the optical light curve. Quantitatively, there are several interesting deviations from this behaviour, however. The Balmer lines show P Cygni profiles and have their maximum strength (both in equivalent width and line flux) after the peak of the optical light curve, at the descending branch of the light curve. The line-width during maximum phase is smaller than during minimum, but it has a local maximum close to the peak of the visual light curve. We derive mass-loss rates over the cycle from the Hα line and find the highest mass loss rates (log dot {M}/({M}_sun yr-1) ~ -3.8, about a factor of five higher than in the minimum, where we find log dot {M}/({M}_sun yr-1) ~ -4.5) after the visual maximum. Line-splitting is very commonly observed, especially on the rise to maximum and on the descending branch from maximum. The components are very long-lived (years) and are probably unrelated to similar-looking line-splitting events in normal supergiants. Small apparent accelerations of the components are observed. The change in radial velocity could be due to successive narrowing of the components, with the absorption disappearing at small expansion velocities first. In general, the line-splitting is more likely the result of missing absorption at intermediate velocities than of

  12. Shape control in wafer-based aperiodic 3D nanostructures

    International Nuclear Information System (INIS)

    Jeong, Hyeon-Ho; Mark, Andrew G; Gibbs, John G; Fischer, Peer; Reindl, Thomas; Waizmann, Ulrike; Weis, Jürgen

    2014-01-01

    Controlled local fabrication of three-dimensional (3D) nanostructures is important to explore and enhance the function of single nanodevices, but is experimentally challenging. We present a scheme based on e-beam lithography (EBL) written seeds, and glancing angle deposition (GLAD) grown structures to create nanoscale objects with defined shapes but in aperiodic arrangements. By using a continuous sacrificial corral surrounding the features of interest we grow isolated 3D nanostructures that have complex cross-sections and sidewall morphology that are surrounded by zones of clean substrate. (papers)

  13. Characteristics of aperiodic sequence of slip events caused by interaction between seismic patches and that caused be self-organized stress heterogeneity

    Science.gov (United States)

    Kato, N.

    2017-12-01

    Numerical simulations of earthquake cycles are conducted to investigate the origin of complexity of earthquake recurrence. There are two main causes of the complexity. One is self-organized stress heterogeneity due to dynamical effect. The other is the effect of interaction between some fault patches. In the model, friction on the fault is assumed to obey a rate- and state-dependent friction law. Circular patches of velocity-weakening frictional property are assumed on the fault. On the remaining areas of the fault, velocity-strengthening friction is assumed. We consider three models: Single patch model, two-patch model, and three-patch model. In the first model, the dynamical effect is mainly examined. The latter two models take into consideration the effect of interaction as well as the dynamical effect. Complex multiperiodic or aperiodic sequences of slip events occur when slip behavior changes from the seismic to aseismic, and when the degree of interaction between seismic patches is intermediate. The former is observed in all the models, and the latter is observed in the two-patch model and the three-patch model. Evolution of spatial distribution of shear stress on the fault suggests that aperiodicity at the transition from seismic to aseismic slip is caused by self-organized stress heterogeneity. The iteration maps of recurrence intervals of slip events in aperiodic sequences are examined, and they are approximately expressed by simple curves for aperiodicity at the transition from seismic to aseismic slip. In contrast, the iteration maps for aperiodic sequences caused by interaction between seismic patches are scattered and they are not expressed by simple curves. This result suggests that complex sequences caused by different mechanisms may be distinguished.

  14. Variable Stars Observed in the Galactic Disk by AST3-1 from Dome A, Antarctica

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Lingzhi; Ma, Bin; Hu, Yi; Liu, Qiang; Shang, Zhaohui [Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China); Li, Gang; Fu, Jianning [Department of Astronomy, Beijing Normal University, Beijing, 100875 (China); Wang, Lifan; Cui, Xiangqun; Du, Fujia; Gong, Xuefei; Li, Xiaoyan; Li, Zhengyang; Yuan, Xiangyan; Zhou, Jilin [Chinese Center for Antarctic Astronomy, Nanjing 210008 (China); Ashley, Michael C. B. [School of Physics, University of New South Wales, NSW 2052 (Australia); Pennypacker, Carl R. [Center for Astrophysics, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); York, Donald G., E-mail: wanglingzhi@bao.ac.cn [Department of Astronomy and Astrophysics and Enrico Fermi Institute, University of Chicago, Chicago, IL 60637 (United States)

    2017-03-01

    AST3-1 is the second-generation wide-field optical photometric telescope dedicated to time-domain astronomy at Dome A, Antarctica. Here, we present the results of an i -band images survey from AST3-1 toward one Galactic disk field. Based on time-series photometry of 92,583 stars, 560 variable stars were detected with i magnitude ≤16.5 mag during eight days of observations; 339 of these are previously unknown variables. We tentatively classify the 560 variables as 285 eclipsing binaries (EW, EB, and EA), 27 pulsating variable stars ( δ Scuti, γ Doradus, δ Cephei variable, and RR Lyrae stars), and 248 other types of variables (unclassified periodic, multiperiodic, and aperiodic variable stars). Of the eclipsing binaries, 34 show O’Connell effects. One of the aperiodic variables shows a plateau light curve and another variable shows a secondary maximum after peak brightness. We also detected a complex binary system with an RS CVn-like light-curve morphology; this object is being followed-up spectroscopically using the Gemini South telescope.

  15. Optimized emission in nanorod arrays through quasi-aperiodic inverse design.

    Science.gov (United States)

    Anderson, P Duke; Povinelli, Michelle L

    2015-06-01

    We investigate a new class of quasi-aperiodic nanorod structures for the enhancement of incoherent light emission. We identify one optimized structure using an inverse design algorithm and the finite-difference time-domain method. We carry out emission calculations on both the optimized structure as well as a simple periodic array. The optimized structure achieves nearly perfect light extraction while maintaining a high spontaneous emission rate. Overall, the optimized structure can achieve a 20%-42% increase in external quantum efficiency relative to a simple periodic design, depending on material quality.

  16. Inter-Annual Variability in Blue Whale Distribution off Southern Sri Lanka between 2011 and 2012

    Directory of Open Access Journals (Sweden)

    Asha de Vos

    2014-07-01

    Full Text Available Blue whale (Balaenoptera musculus movements are often driven by the availability of their prey in space and time. While globally blue whale populations undertake long-range migrations between feeding and breeding grounds, those in the northern Indian Ocean remain in low latitude waters throughout the year with the implication that the productivity of these waters is sufficient to support their energy needs. A part of this population remains around Sri Lanka where they are usually recorded close to the southern coast during the Northeast Monsoon. To investigate inter-annual variability in sighting locations, we conducted systematic Conductivity-Temperature-Depth (CTD and visual surveys between January–March 2011 and January–March 2012. In 2011, there was a notable decrease in inshore sightings compared to 2009 and 2012 (p < 0.001. CTD data revealed that in 2011 there was increased freshwater in the upper water column accompanied by deeper upwelling than in 2012. We hypothesise that anomalous rainfall, along with higher turbidity resulting from river discharge, affected the productivity of the inshore waters and caused a shift in blue whale prey and, consequently, the distribution of the whales themselves. An understanding of how predators and their prey respond to environmental variability is important for predicting how these species will respond to long-term changes. This is especially important given the rapid temperature increases predicted for the semi-enclosed northern Indian Ocean.

  17. Application of Artificial Neural Networks (ANNs for Weight Predictions of Blue Crabs (Callinectes sapidus RATHBUN, 1896 Using Predictor Variables

    Directory of Open Access Journals (Sweden)

    C. TURELI BILEN

    2011-10-01

    Full Text Available An evaluation of the performance of artificial networks (ANNs to estimate the weights of blue crab (Callinectes sapidus catches in Yumurtalık Cove (Iskenderun Bay that uses measured predictor variables is presented, including carapace width (CW, sex (male, female and female with eggs, and sampling month. Blue crabs (n=410 were collected each month between 15 September 1996 and 15 May 1998. Sex, CW, and sampling month were used and specified in the input layer of the network. The weights of the blue crabs were utilized in the output layer of the network. A multi-layer perception architecture model was used and was calibrated with the Levenberg Marguardt (LM algorithm. Finally, the values were determined by the ANN model using the actual data. The mean square error (MSE was measured as 3.3, and the best results had a correlation coefficient (R of 0.93. We compared the predictive capacity of the general linear model (GLM versus the Artificial Neural Network model (ANN for the estimation of the weights of blue crabs from independent field data. The results indicated the higher performance capacity of the ANN to predict weights compared to the GLM (R=0.97 vs. R=0.95, raw variable when evaluated against independent field data.

  18. Dual-wavelength green laser with a 4.5 THz frequency difference based on self-frequency- doubling in Nd3+ -doped aperiodically poled lithium niobate.

    Science.gov (United States)

    Maestre, H; Torregrosa, A J; Fernández-Pousa, C R; Rico, M L; Capmany, J

    2008-05-01

    We report a dual-wavelength continuous-wave laser at 542.4 and 546.8 nm based on an Nd(3+)-doped aperiodically poled lithium niobate crystal. Two fundamental infrared (IR) wavelengths at 1084.8 and 1093.6 nm are simultaneously oscillated and self-frequency-doubled to green. The aperiodic domain distribution patterned in the crystal allows for quasi-phase matched self-frequency-doubling of both IR fundamentals while avoiding their sum-frequency mixing.

  19. Influences of Fundamental Frequency, Formant Frequencies, Aperiodicity, and Spectrum Level on the Perception of Voice Gender

    Science.gov (United States)

    Skuk, Verena G.; Schweinberger, Stefan R.

    2014-01-01

    Purpose: To determine the relative importance of acoustic parameters (fundamental frequency [F0], formant frequencies [FFs], aperiodicity, and spectrum level [SL]) on voice gender perception, the authors used a novel parameter-morphing approach that, unlike spectral envelope shifting, allows the application of nonuniform scale factors to transform…

  20. Radiation-disorder and aperiodicity in irradiated ceramics

    International Nuclear Information System (INIS)

    Hobbs, L.W.

    1992-01-01

    This final technical report documents the accomplishments of the program of research entitled ''Radiation Disorder and Aperiodicity in Irradiated Ceramics'' for the period June 22, 1989--June 21, 1992. This research forms the latest part on an on-going program, begun at MIT in 1983 under DOE support, which has had as its objectives investigation of the responses in radiation environments of ceramics heavily-irradiated with electrons, neutrons and ions, with potential applications to fusion energy technology and high-level nuclear waste storage. Materials investigated have included SiO 2 , MgAl 2 O 4 , Al 23 O 27 N 5 , SiC, BeO, LiAlO 2 , Li 2 ZrO 3 , CaTiO 3 KTaO 3 and Ca(Zr, Pu)Ti 2 O 7 . The program initially proposed for 1989 had as its major objectives two main thrusts: (1) research on defect aggregation in irradiated non-oxide ceramics, and (2) research on irradiation-induced amorphization of network silicas and phosphates

  1. A Blue Lagoon Function

    DEFF Research Database (Denmark)

    Markvorsen, Steen

    2007-01-01

    We consider a specific function of two variables whose graph surface resembles a blue lagoon. The function has a saddle point $p$, but when the function is restricted to any given straight line through $p$ it has a {\\em{strict local minimum}} along that line at $p$.......We consider a specific function of two variables whose graph surface resembles a blue lagoon. The function has a saddle point $p$, but when the function is restricted to any given straight line through $p$ it has a {\\em{strict local minimum}} along that line at $p$....

  2. The nature of the nebula associated with the luminous blue variable star WRA 751

    OpenAIRE

    Hutsemekers, Damien; van Drom, E.

    1991-01-01

    Narrow-band filter imagery as well as medium to high resolution spectroscopy of the nebula surrounding the luminous blue variable (LBV) star WRA 751 are presented. The nebula appears as a slowly expanding H II region of low excitation characterized by a significant N/O overabundance which may be due to the presence in the nebula of nuclear processed material ejected by the star. With the recent discovery of a nebula around HR Car, all but one known galactic LBVs are now shown to be associated...

  3. Theoretical and experimental study of bent fully aperiodic large-pitch fibers for enhancing the high-order modes delocalization

    Science.gov (United States)

    du Jeu, Rémi; Dauliat, Romain; Darwich, Dia; Auguste, Jean-Louis; Benoît, Aurélien; Leconte, Baptiste; Malleville, Marie-Alicia; Jamier, Raphaël.; Schuster, Kay; Roy, Philippe

    2018-02-01

    The power scaling of fiber lasers and amplifiers has triggered an extensive development of large-mode area fibers among which the most promising are the distributed mode filtering fibers and the large-pitch fibers. These structures enable for an effective higher-order modes delocalization and subsequently a singlemode emission. An interesting alternative consists in using the fully-aperiodic large-pitch fibers, into which the standard air-silica photonic crystal cladding is replaced by an aperiodic pattern made of solid low-index inclusions cladding. However, in such a structure, the core and the background cladding material surrounding it must have rigorously the same refractive index. Current synthesis processes and measurement techniques offer respectively a maximum resolution of 5×10-4 and 1×10-4 while the indexmatching must be as precise as 1×10-5 . Lately a gain material with a refractive index 1.5×10-4 higher than that of the background cladding material was fabricated, thus re-confining the first higher-order modes in the core. A numerical study is carried out on the benefit of bending such fully-aperiodic fiber to counteract this phenomenon. Optimized bending axis and radius have been determined. Experiments are done in a laser cavity operating at 1030 nm using an 88cm-long 51μm core diameter ytterbium-doped fiber. Results demonstrate an improvement of the M2 from 1.7 when the fiber is kept straight to 1.2 when it is bent with a 100 to 60 cm bend radius. These primary results are promising for future power scaling.

  4. Visuo-manual tracking: does intermittent control with aperiodic sampling explain linear power and non-linear remnant without sensorimotor noise?

    Science.gov (United States)

    Gollee, Henrik; Gawthrop, Peter J; Lakie, Martin; Loram, Ian D

    2017-11-01

    A human controlling an external system is described most easily and conventionally as linearly and continuously translating sensory input to motor output, with the inevitable output remnant, non-linearly related to the input, attributed to sensorimotor noise. Recent experiments show sustained manual tracking involves repeated refractoriness (insensitivity to sensory information for a certain duration), with the temporary 200-500 ms periods of irresponsiveness to sensory input making the control process intrinsically non-linear. This evidence calls for re-examination of the extent to which random sensorimotor noise is required to explain the non-linear remnant. This investigation of manual tracking shows how the full motor output (linear component and remnant) can be explained mechanistically by aperiodic sampling triggered by prediction error thresholds. Whereas broadband physiological noise is general to all processes, aperiodic sampling is associated with sensorimotor decision making within specific frontal, striatal and parietal networks; we conclude that manual tracking utilises such slow serial decision making pathways up to several times per second. The human operator is described adequately by linear translation of sensory input to motor output. Motor output also always includes a non-linear remnant resulting from random sensorimotor noise from multiple sources, and non-linear input transformations, for example thresholds or refractory periods. Recent evidence showed that manual tracking incurs substantial, serial, refractoriness (insensitivity to sensory information of 350 and 550 ms for 1st and 2nd order systems respectively). Our two questions are: (i) What are the comparative merits of explaining the non-linear remnant using noise or non-linear transformations? (ii) Can non-linear transformations represent serial motor decision making within the sensorimotor feedback loop intrinsic to tracking? Twelve participants (instructed to act in three prescribed

  5. Voltage dependency of transmission probability of aperiodic DNA molecule

    Science.gov (United States)

    Wiliyanti, V.; Yudiarsah, E.

    2017-07-01

    Characteristics of electron transports in aperiodic DNA molecules have been studied. Double stranded DNA model with the sequences of bases, GCTAGTACGTGACGTAGCTAGGATATGCCTGA, in one chain and its complements on the other chains has been used. Tight binding Hamiltonian is used to model DNA molecules. In the model, we consider that on-site energy of the basis has a linearly dependency on the applied electric field. Slater-Koster scheme is used to model electron hopping constant between bases. The transmission probability of electron from one electrode to the next electrode is calculated using a transfer matrix technique and scattering matrix method simultaneously. The results show that, generally, higher voltage gives a slightly larger value of the transmission probability. The applied voltage seems to shift extended states to lower energy. Meanwhile, the value of the transmission increases with twisting motion frequency increment.

  6. MN112: a new Galactic candidate luminous blue variable

    Science.gov (United States)

    Gvaramadze, V. V.; Kniazev, A. Y.; Fabrika, S.; Sholukhova, O.; Berdnikov, L. N.; Cherepashchuk, A. M.; Zharova, A. V.

    2010-06-01

    We report the discovery of a new Galactic candidate luminous blue variable (cLBV) via detection of an infrared circular nebula and follow-up spectroscopy of its central star. The nebula, MN112, is one of many dozens of circular nebulae detected at 24μm in the Spitzer Space Telescope archival data, whose morphology is similar to that of nebulae associated with known (c)LBVs and related evolved massive stars. Specifically, the core-halo morphology of MN112 bears a striking resemblance to the circumstellar nebula associated with the Galactic cLBV GAL079.29+00.46, which suggests that both nebulae might have a similar origin and that the central star of MN112 is an LBV. The spectroscopy of the central star showed that its spectrum is almost identical to that of the bona fide LBV PCygni, which also supports the LBV classification of the object. To further constrain the nature of MN112, we searched for signatures of possible high-amplitude (>~1mag) photometric variability of the central star using archival and newly obtained photometric data covering a 45-yr period. We found that the B magnitude of the star was constant within error margins, while in the I band the star brightened by ~=0.4mag during the last 17 yr. Although the non-detection of large photometric variability leads us to use the prefix `candidate' in the classification of MN112, we remind the readers that the long-term photometric stability is not unusual for genuine LBVs and that the brightness of PCygni remained relatively stable during the last three centuries. Partially based on observations collected at the German-Spanish Astronomical Center, Calar Alto, jointly operated by the Max-Planck-Institut für Astronomie Heidelberg and the Instituto de Astrofísica de Andalucía (CSIC). E-mail: vgvaram@mx.iki.rssi.ru (VVG); akniazev@saao.ac.za (AYK); fabrika@sao.ru (SF); olga@sao.ru (OS); berdnik@sai.msu.ru (LNB); cher@sai.msu.ru (AMC); alla@sai.msu.ru (AVZ)

  7. Aperiodic nanoplasmonic devices for directional colour filtering and sensing.

    Science.gov (United States)

    Davis, Matthew S; Zhu, Wenqi; Xu, Ting; Lee, Jay K; Lezec, Henri J; Agrawal, Amit

    2017-11-07

    Exploiting the wave-nature of light in its simplest form, periodic architectures have enabled a panoply of tunable optical devices with the ability to perform useful functions such as filtering, spectroscopy, and multiplexing. Here, we remove the constraint of structural periodicity to enhance, simultaneously, the performance and functionality of passive plasmonic devices operating at optical frequencies. By using a physically intuitive, first-order interference model of plasmon-light interactions, we demonstrate a simple and efficient route towards designing devices with flexible, multi-spectral optical response, fundamentally not achievable using periodic architectures. Leveraging this approach, we experimentally implement ultra-compact directional light-filters and colour-sorters exhibiting angle- or spectrally-tunable optical responses with high contrast, and low spectral or spatial crosstalk. Expanding the potential of aperiodic systems to implement tailored spectral and angular responses, these results hint at promising applications in solar-energy harvesting, optical signal multiplexing, and integrated sensing.

  8. Discovery of a new Galactic bona fide luminous blue variable with Spitzer★

    Science.gov (United States)

    Gvaramadze, V. V.; Kniazev, A. Y.; Berdnikov, L. N.; Langer, N.; Grebel, E. K.; Bestenlehner, J. M.

    2014-11-01

    We report the discovery of a circular mid-infrared shell around the emission-line star Wray 16-137 using archival data of the Spitzer Space Telescope. Follow-up optical spectroscopy of Wray 16-137 with the Southern African Large Telescope revealed a rich emission spectrum typical of the classical luminous blue variables (LBVs) like P Cygni. Subsequent spectroscopic and photometric observations showed drastic changes in the spectrum and brightness during the last three years, meaning that Wray 16-137 currently undergoes an S Dor-like outburst. Namely, we found that the star has brightened by ≈1 mag in the V and Ic bands, while its spectrum became dominated by Fe II lines. Taken together, our observations unambiguously show that Wray 16-137 is a new member of the family of Galactic bona fide LBVs.

  9. Confirmation of the Luminous Blue Variable Status of MWC 930

    Directory of Open Access Journals (Sweden)

    A. S. Miroshnichenko

    2014-01-01

    Full Text Available We present spectroscopic and photometric observations of the emission-line star MWC 930 (V446 Sct during its long-term optical brightening in 2006–2013. Based on our earlier data we suggested that the object has features found in Luminous Blue Variables (LBV, such as a high luminosity (~3 105 L⊙, a low wind terminal velocity (~140 km s−1, and a tendency to show strong brightness variations (~1 mag over 20 years. For the last ~7 years it has been exhibiting a continuous optical and near-IR brightening along with a change of the emission-line spectrum appearance and cooling of the star’s photosphere. We present the object’s V-band light curve, analyze the spectral variations, and compare the observed properties with those of other recognized Galactic LBVs, such as AG Car and HR Car. Overall we conclude the MWC 930 is a bona fide Galactic LBV that is currently in the middle of an S Dor cycle.

  10. The evolution of the Gutenberg-Richter, b-value, throughout periodic and aperiodic stick-slip cycles

    Science.gov (United States)

    Bolton, D. C.; Riviere, J.; Marone, C.; Johnson, P. A.

    2017-12-01

    The Gutenberg-Richter earthquake size statistic, b value, is a useful proxy for documenting the state of stress on a fault and understanding precursory phenomena preceding dynamic failure. It has been shown that the b value varies systematically as a function of position within the seismic cycle. Frictional studies on intact rock samples with saw-cut faults have shown that b value decreases continuously preceding failure. For intact rock samples, the spatiotemporal changes in b value are thought to be related to the evolution of asperities and micro-cracks. However, few studies have shown how b value evolves spatially and temporally for fault zones containing gouge and wear materials. We hypothesize that the micromechanical mechanisms acting within fault gouge, such as creation and destruction of force chains, grain rolling, sliding, jamming and fracturing play an important role in the evolution of b value and that they may have distinct signatures during periodic and aperiodic cycles of stick-slip frictional motion. We report results from experiments conducted on simulated fault gouge using a biaxial deformation apparatus in a double-direct shear configuration. Acoustic emissions (AEs) are recorded at 4 MHz from 36 P-polarized piezoelectric transducers, which are embedded in steel blocks located adjacent to the fault zone. We compute the frequency-magnitude distribution of detected AEs using a moving window in events where each window is overlapped by 75%. We report on the evolution of b value as a function of normal stress and gouge layer thickness. For periodic slip events, b value reaches a maximum value immediately after a slip event and decreases continuously until the next failure. Aperiodic slip events show similar trends in b-value initially, however unlike periodic slip events, b value reaches a steady state value before failure occurs. In addition, for periodic slip events the magnitude of the change in b value scales inversely with gouge layer thickness

  11. Energy band and transport properties in magnetic aperiodic graphene superlattices of Thue-Morse sequence

    Science.gov (United States)

    Yin, Yiheng; Niu, Yanxiong; Zhang, Huiyun; Zhang, Yuping; Liu, Haiyue

    2016-02-01

    Utilizing the transfer matrix method, we develop the electronic band structure and transport properties in Thue-Morse aperiodic graphene superlattices with magnetic barriers. It is found that the normal transmission is blocked and the position of the Dirac point can be shifted along the wavevector axis by changing the height and width ratio of magnetic barriers, which is intrinsic different from electronic field modulated superlattices. In addition, the angular threshold property of the transmission spectra and the oscillatory property of the conductance have been studied.

  12. Discovery of a new bona fide luminous blue variable in Norma

    Science.gov (United States)

    Gvaramadze, V. V.; Kniazev, A. Y.; Berdnikov, L. N.

    2015-12-01

    We report the results of optical spectroscopy of the candidate evolved massive star MN44 revealed via detection of a circular shell with the Spitzer Space Telescope. First spectra taken in 2009 May-June showed the Balmer lines in emission as well as numerous emission lines of iron, which is typical of luminous blue variables (LBVs) near the visual maximum. New observations carried out in 2015 May-September detected significant changes in the spectrum, indicating that the star became hotter. We found that these changes are accompanied by significant brightness variability of MN44. In particular, the Ic-band brightness decreased by ≈ 1.6 mag during the last six years and after reaching its minimum in 2015 June has started to increase. Using archival data, we also found that the Ic-band brightness increased by ≈3 mag in ≈30 yr preceding our observations. MN44 therefore represents the 17th known example of the Galactic bona fide LBVs. We detected a nitrogen-rich knot to the north-west of the star, which might represent an interstellar cloudlet interacting with the circumstellar shell. We discuss a possible association between MN44 and the INTEGRAL transient source of hard X-ray emission IGR J16327-4940, implying that MN44 might be either a colliding-wind binary or a high-mass X-ray binary.

  13. Real-time remedial action against aperiodic small signal rotor angle instability

    DEFF Research Database (Denmark)

    Weckesser, Johannes Tilman Gabriel; Jóhannsson, Hjörtur; Østergaard, Jacob

    2016-01-01

    This paper presents a method that in real-time determines remedial actions, which restore stable operation with respect to aperiodic small signal rotor angle stability (ASSRAS) when insecure or unstable operation has been detected. An ASSRAS assessment method is used to monitor the stability...... impedance plane to determine an active power redispatch among selected generators to restore stable and secure operation. Since the method is purely based on analytically derived expression, the computation of the remedial actions is fast and well suited for real-time operation. The method was tested...... boundary for each generator in real-time. The ASSRAS boundary represents the condition when a generator reaches the maximum steady state active power injection. The proposed control method exploits analytically derived expressions for the ASSRAS boundary and other characteristic curves in the injection...

  14. Prolonged Sitting is Associated with Attenuated Heart Rate Variability during Sleep in Blue-Collar Workers

    Directory of Open Access Journals (Sweden)

    David M Hallman

    2015-11-01

    Full Text Available Prolonged sitting is associated with increased risk for cardiovascular diseases and mortality. However, research into the physiological determinants underlying this relationship is still in its infancy. The aim of the study was to determine the extent to which occupational and leisure-time sitting are associated with nocturnal heart rate variability (HRV in blue-collar workers. The study included 138 blue-collar workers (mean age 45.5 (SD 9.4 years. Sitting-time was measured objectively for four days using tri-axial accelerometers (Actigraph GT3X+ worn on the thigh and trunk. During the same period, a heart rate monitor (Actiheart was used to sample R-R intervals from the electrocardiogram. Time and frequency domain indices of HRV were only derived during nighttime sleep, and used as markers of cardiac autonomic modulation. Regression analyses with multiple adjustments (age, gender, body mass index, smoking, job-seniority, physical work-load, influence at work, and moderate-to-vigorous physical activity were used to investigate the association between sitting time and nocturnal HRV. We found that occupational sitting-time was negatively associated (p < 0.05 with time and frequency domain HRV indices. Sitting-time explained up to 6% of the variance in HRV, independent of the covariates. Leisure-time sitting was not significantly associated with any HRV indices (p > 0.05. In conclusion, objectively measured occupational sitting-time was associated with reduced nocturnal HRV in blue-collar workers. This indicates an attenuated cardiac autonomic regulation with increasing sitting-time at work regardless of moderate-to-vigorous physical activity. The implications of this association for cardiovascular disease risk warrant further investigation via long-term prospective studies and intervention studies.

  15. Self-similar transmission properties of aperiodic Cantor potentials in gapped graphene

    Science.gov (United States)

    Rodríguez-González, Rogelio; Rodríguez-Vargas, Isaac; Díaz-Guerrero, Dan Sidney; Gaggero-Sager, Luis Manuel

    2016-01-01

    We investigate the transmission properties of quasiperiodic or aperiodic structures based on graphene arranged according to the Cantor sequence. In particular, we have found self-similar behaviour in the transmission spectra, and most importantly, we have calculated the scalability of the spectra. To do this, we implement and propose scaling rules for each one of the fundamental parameters: generation number, height of the barriers and length of the system. With this in mind we have been able to reproduce the reference transmission spectrum, applying the appropriate scaling rule, by means of the scaled transmission spectrum. These scaling rules are valid for both normal and oblique incidence, and as far as we can see the basic ingredients to obtain self-similar characteristics are: relativistic Dirac electrons, a self-similar structure and the non-conservation of the pseudo-spin.

  16. Applied optics. Gain modulation by graphene plasmons in aperiodic lattice lasers.

    Science.gov (United States)

    Chakraborty, S; Marshall, O P; Folland, T G; Kim, Y-J; Grigorenko, A N; Novoselov, K S

    2016-01-15

    Two-dimensional graphene plasmon-based technologies will enable the development of fast, compact, and inexpensive active photonic elements because, unlike plasmons in other materials, graphene plasmons can be tuned via the doping level. Such tuning is harnessed within terahertz quantum cascade lasers to reversibly alter their emission. This is achieved in two key steps: first, by exciting graphene plasmons within an aperiodic lattice laser and, second, by engineering photon lifetimes, linking graphene's Fermi energy with the round-trip gain. Modal gain and hence laser spectra are highly sensitive to the doping of an integrated, electrically controllable, graphene layer. Demonstration of the integrated graphene plasmon laser principle lays the foundation for a new generation of active, programmable plasmonic metamaterials with major implications across photonics, material sciences, and nanotechnology. Copyright © 2016, American Association for the Advancement of Science.

  17. Multispectral selective near-perfect light absorption by graphene monolayer using aperiodic multilayer microstructures

    Science.gov (United States)

    Zand, Iman; Dalir, Hamed; Chen, Ray T.; Dowling, Jonathan P.

    2018-03-01

    We investigate one-dimensional aperiodic multilayer microstructures in order to achieve near-total absorptions at preselected wavelengths in a graphene monolayer. The proposed structures are designed using a genetic optimization algorithm coupled to a transfer matrix code. Coupled-mode-theory analysis, consistent with transfer matrix method results, indicates the existence of a critical coupling in the graphene monolayer for perfect absorptions. Our findings show that the near-total-absorption peaks are highly tunable and can be controlled simultaneously or independently in a wide range of wavelengths in the near-infrared and visible ranges. The proposed approach is metal-free, does not require surface texturing or patterning, and can be also applied for other two-dimensional materials.

  18. Aperiodic pressure pulsation under non optimal hydraulic turbine regimes at low swirl number

    Science.gov (United States)

    Skripkin, S. G.; Tsoy, M. A.; Kuibin, P. A.; Shtork, S. I.

    2017-09-01

    Off-design operating conditions of hydraulic turbines is hindered by pressure fluctuations in the draft tube of the turbine. A precessing helical vortex rope develops, which imperils the mechanical structure and limits the operation flexibility of hydropower station. Understanding of the underlying instabilities of precessing vortex rope at low swirl number is incomplete. In this paper flow regimes with different residual swirl is analysed, particular attention is paid to the regime with a small swirl parameter. Study defines upper and low boundaries of regime where aperiodic pressure surge is observed. Flow field at the runner exit is investigated by Laser Doppler Velocimetry and high-speed visualizations, which are complemented draft tube wall pressure measurements.

  19. Wave propagation in one-dimensional solid-fluid quasi-periodic and aperiodic phononic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Chen Ali, E-mail: alchen@bjtu.edu.cn [Institute of Engineering Mechanics, Beijing Jiaotong University, Beijing 100044 (China); Wang Yuesheng [Institute of Engineering Mechanics, Beijing Jiaotong University, Beijing 100044 (China); Zhang Chuanzeng [Department of Civil Engineering, University of Siegen, D-57068 Siegen (Germany)

    2012-02-01

    The propagation of the elastic waves in one-dimensional (1D) solid-fluid quasi-periodic phononic crystals is studied by employing the concept of the localization factor, which is calculated by the transfer matrix method. The solid-fluid interaction effect at the interfaces between the solid and the fluid components is considered. For comparison, the periodic systems and aperiodic Thue-Morse sequence are also analyzed in this paper. The splitting phenomenon of the pass bands and bandgaps are discussed for these 1D solid-fluid systems. At last the influences of the material impedance ratios on the band structures of the 1D solid-fluid quasi-periodic phononic crystals arranged as Fibonacci sequence are discussed.

  20. Achieving sub-50 nm controlled diameter of aperiodic Si nanowire arrays by ultrasonic catalyst removal for photonic applications

    Science.gov (United States)

    Chaliyawala, Harsh A.; Purohit, Zeel; Khanna, Sakshum; Ray, Abhijit; Pati, Ranjan K.; Mukhopadhyay, Indrajit

    2018-05-01

    We report an alternative approach to fabricate the vertically aligned aperiodic Si nanowire arrays by controlling the diameter of the Ag nanoparticles and tuneable ultrasonic removal. The process begins by sputtering the Ag thin film (t=5 nm) on the Si/SiO2 substrates. Followed by Ag thin film, annealed for various temperature (T=300°C, 400°C, 500°C and 600°C) to selectively achieve a high density, well-spaced and diameter controlled Ag nanoparticles (AgNPs) on the Si/SiO2 substrates. The sacrificial layer of AgNPs size indicates the controlled diameter of the Si nanowire arrays. Image J analysis for various annealed samples gives an indication of the high density, uniformity and equal distribution of closely packed AgNPs. Furthermore, the AgNPs covered with Au/Pd mesh (5 nm) as a template, was removed by ultrasonication in the etchant solution for several times in different intervals of preparation. The conventional and facile metal assisted electroless etching approach was finally employed to fabricate the vertically aperiodic sub-50 nm SiNWAs, can be applicable to various nanoscale opto-electronic applications.

  1. Tunable photonic crystals with partial bandgaps from blue phase colloidal crystals and dielectric-doped blue phases.

    Science.gov (United States)

    Stimulak, Mitja; Ravnik, Miha

    2014-09-07

    Blue phase colloidal crystals and dielectric nanoparticle/polymer doped blue phases are demonstrated to combine multiple components with different symmetries in one photonic material, creating a photonic crystal with variable and micro-controllable photonic band structure. In this composite photonic material, one contribution to the band structure is determined by the 3D periodic birefringent orientational profile of the blue phases, whereas the second contribution emerges from the regular array of the colloidal particles or from the dielectric/nanoparticle-doped defect network. Using the planewave expansion method, optical photonic bands of the blue phase I and II colloidal crystals and related nanoparticle/polymer doped blue phases are calculated, and then compared to blue phases with no particles and to face-centred-cubic and body-centred-cubic colloidal crystals in isotropic background. We find opening of local band gaps at particular points of Brillouin zone for blue phase colloidal crystals, where there were none in blue phases without particles or dopants. Particle size and filling fraction of the blue phase defect network are demonstrated as parameters that can directly tune the optical bands and local band gaps. In the blue phase I colloidal crystal with an additionally doped defect network, interestingly, we find an indirect total band gap (with the exception of one point) at the entire edge of SC irreducible zone. Finally, this work demonstrates the role of combining multiple - by symmetry - differently organised components in one photonic crystal material, which offers a novel approach towards tunable soft matter photonic materials.

  2. Active Luminous Blue Variables in the Large Magellanic Cloud

    Energy Technology Data Exchange (ETDEWEB)

    Walborn, Nolan R. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Gamen, Roberto C.; Lajús, Eduardo Fernández [Instituto de Astrofísica de La Plata, CONICET–UNLP and Facultad de Ciencias Astronómicas y Geofísicas, UNLP, Paseo del Bosque s/n, La Plata (Argentina); Morrell, Nidia I. [Las Campanas Observatory, Carnegie Observatories, Casilla 601, La Serena (Chile); Barbá, Rodolfo H. [Departamento de Física y Astronomía, Universidad de La Serena, Cisternas 1200 Norte, La Serena (Chile); Angeloni, Rodolfo, E-mail: walborn@stsci.edu, E-mail: rgamen@fcaglp.unlp.edu.ar, E-mail: eflajus@fcaglp.unlp.edu.ar, E-mail: nmorrell@lco.cl, E-mail: rbarba@dfuls.cl, E-mail: rangelon@gemini.edu [Gemini Observatory, Colina El Pino, Casilla 603, La Serena (Chile)

    2017-07-01

    We present extensive spectroscopic and photometric monitoring of two famous and currently highly active luminous blue variables (LBVs) in the Large Magellanic Cloud (LMC), together with more limited coverage of three further, lesser known members of the class. R127 was discovered as an Ofpe/WN9 star in the 1970s but entered a classical LBV outburst in or about 1980 that is still in progress, thus enlightening us about the minimum state of such objects. R71 is currently the most luminous star in the LMC and continues to provide surprises, such as the appearance of [Ca ii] emission lines, as its spectral type becomes unprecedentedly late. Most recently, R71 has developed inverse P Cyg profiles in many metal lines. The other objects are as follows: HDE 269582, now a “second R127” that has been followed from Ofpe/WN9 to A type in its current outburst; HDE 269216, which changed from late B in 2014 to AF in 2016, its first observed outburst; and R143 in the 30 Doradus outskirts. The light curves and spectroscopic transformations are correlated in remarkable detail and their extreme reproducibility is emphasized, both for a given object and among all of them. It is now believed that some LBVs proceed directly to core collapse. One of these unstable LMC objects may thus oblige in the near future, teaching us even more about the final stages of massive stellar evolution.

  3. Active Luminous Blue Variables in the Large Magellanic Cloud

    Science.gov (United States)

    Walborn, Nolan R.; Gamen, Roberto C.; Morrell, Nidia I.; Barbá, Rodolfo H.; Fernández Lajús, Eduardo; Angeloni, Rodolfo

    2017-07-01

    We present extensive spectroscopic and photometric monitoring of two famous and currently highly active luminous blue variables (LBVs) in the Large Magellanic Cloud (LMC), together with more limited coverage of three further, lesser known members of the class. R127 was discovered as an Ofpe/WN9 star in the 1970s but entered a classical LBV outburst in or about 1980 that is still in progress, thus enlightening us about the minimum state of such objects. R71 is currently the most luminous star in the LMC and continues to provide surprises, such as the appearance of [Ca II] emission lines, as its spectral type becomes unprecedentedly late. Most recently, R71 has developed inverse P Cyg profiles in many metal lines. The other objects are as follows: HDE 269582, now a “second R127” that has been followed from Ofpe/WN9 to A type in its current outburst; HDE 269216, which changed from late B in 2014 to AF in 2016, its first observed outburst; and R143 in the 30 Doradus outskirts. The light curves and spectroscopic transformations are correlated in remarkable detail and their extreme reproducibility is emphasized, both for a given object and among all of them. It is now believed that some LBVs proceed directly to core collapse. One of these unstable LMC objects may thus oblige in the near future, teaching us even more about the final stages of massive stellar evolution.

  4. Active Luminous Blue Variables in the Large Magellanic Cloud

    International Nuclear Information System (INIS)

    Walborn, Nolan R.; Gamen, Roberto C.; Lajús, Eduardo Fernández; Morrell, Nidia I.; Barbá, Rodolfo H.; Angeloni, Rodolfo

    2017-01-01

    We present extensive spectroscopic and photometric monitoring of two famous and currently highly active luminous blue variables (LBVs) in the Large Magellanic Cloud (LMC), together with more limited coverage of three further, lesser known members of the class. R127 was discovered as an Ofpe/WN9 star in the 1970s but entered a classical LBV outburst in or about 1980 that is still in progress, thus enlightening us about the minimum state of such objects. R71 is currently the most luminous star in the LMC and continues to provide surprises, such as the appearance of [Ca ii] emission lines, as its spectral type becomes unprecedentedly late. Most recently, R71 has developed inverse P Cyg profiles in many metal lines. The other objects are as follows: HDE 269582, now a “second R127” that has been followed from Ofpe/WN9 to A type in its current outburst; HDE 269216, which changed from late B in 2014 to AF in 2016, its first observed outburst; and R143 in the 30 Doradus outskirts. The light curves and spectroscopic transformations are correlated in remarkable detail and their extreme reproducibility is emphasized, both for a given object and among all of them. It is now believed that some LBVs proceed directly to core collapse. One of these unstable LMC objects may thus oblige in the near future, teaching us even more about the final stages of massive stellar evolution.

  5. On the algebraic characterization of aperiodic tilings related to ADE-root systems

    International Nuclear Information System (INIS)

    Kellendonk, J.

    1992-09-01

    The algebraic characterization of sets of locally equivalent aperiodic tilings, being examples of quantum spaces, is conducted for a certain type of tilings in a manner proposed by A. Connes. These 2-dimensional tilings are obtained by application of the strip method to the root lattice of an ADE-Coxeter group. The plane along which the strip is constructed is determined by the canonical Coxeter element leading to the result that a 2- dimensional tiling decomposes into a cartesian product of two 1- dimensional tilings. The properties of the tilings are investigated, including selfsimilarity, and the determination of the relevant algebraic is considered, namely the ordered K 0 -group of an algebra naturaly assigned to the quantum space. The result also yields an application of the 2-dimensional abstract gap labelling theorem. (orig.)

  6. The DNA electronic specific heat at low temperature: The role of aperiodicity

    Energy Technology Data Exchange (ETDEWEB)

    Sarmento, R.G. [Departamento de Física, Universidade Federal do Rio Grande do Norte, 59072-970, Natal, RN (Brazil); Mendes, G.A. [Departamento de Biofísica e Farmacologia, Universidade Federal do Rio Grande do Norte, 59072-970, Natal, RN (Brazil); Albuquerque, E.L., E-mail: eudenilson@gmail.com [Departamento de Biofísica e Farmacologia, Universidade Federal do Rio Grande do Norte, 59072-970, Natal, RN (Brazil); Fulco, U.L. [Departamento de Biofísica e Farmacologia, Universidade Federal do Rio Grande do Norte, 59072-970, Natal, RN (Brazil); Vasconcelos, M.S. [Escola de Ciências e Tecnologia, Universidade Federal do Rio Grande do Norte, 59072-970, Natal, RN (Brazil); Ujsághy, O. [Department of Theoretical Physics and Condensed Matter Research Group of the Hungarian Academy of Sciences, Budapest University of Technology and Economics, Budafoki út 8, H-1521 Budapest (Hungary); Freire, V.N. [Departamento de Física, Universidade Federal do Ceará, 60455-760, Fortaleza, CE (Brazil); Caetano, E.W.S. [Instituto Federal de Educação, Ciência e Tecnologia do Ceará, 60040-531, Fortaleza, CE (Brazil)

    2012-07-16

    The electronic specific heat spectra at constant volume (C{sub V}) of a long-range correlated extended ladder model, mimicking a DNA molecule, is theoretically analyzed for a stacked array of a double-stranded structure made up from the nucleotides guanine G, adenine A, cytosine C and thymine T. The role of the aperiodicity on C{sub V} is discussed, considering two different nucleotide arrangements with increasing disorder, namely the Fibonacci and the Rudin–Shapiro quasiperiodic structures. Comparisons are made for different values of the band fillings, considering also a finite segment of natural DNA, as part of the human chromosome Ch22. -- Highlights: ► Quasiperiodic sequence to mimic the DNA nucleotides arrangement. ► Electronic tight-binding Hamiltonian model. ► Electronic density of states. ► Electronic specific heat spectra.

  7. Computational Modeling of Bloch Surface Waves in One-Dimensional Periodic and Aperiodic Multilayer Structures

    Science.gov (United States)

    Koju, Vijay

    Photonic crystals and their use in exciting Bloch surface waves have received immense attention over the past few decades. This interest is mainly due to their applications in bio-sensing, wave-guiding, and other optical phenomena such as surface field enhanced Raman spectroscopy. Improvement in numerical modeling techniques, state of the art computing resources, and advances in fabrication techniques have also assisted in growing interest in this field. The ability to model photonic crystals computationally has benefited both the theoretical as well as experimental communities. It helps the theoretical physicists in solving complex problems which cannot be solved analytically and helps to acquire useful insights that cannot be obtained otherwise. Experimentalists, on the other hand, can test different variants of their devices by changing device parameters to optimize performance before fabrication. In this dissertation, we develop two commonly used numerical techniques, namely transfer matrix method, and rigorous coupled wave analysis, in C++ and MATLAB, and use two additional software packages, one open-source and another commercial, to model one-dimensional photonic crystals. Different variants of one-dimensional multilayered structures such as perfectly periodic dielectric multilayers, quasicrystals, aperiodic multilayer are modeled, along with one-dimensional photonic crystals with gratings on the top layer. Applications of Bloch surface waves, along with new and novel aperiodic dielectric multilayer structures that support Bloch surface waves are explored in this dissertation. We demonstrate a slow light configuration that makes use of Bloch Surface Waves as an intermediate excitation in a double-prism tunneling configuration. This method is simple compared to the more usual techniques for slowing light using the phenomenon of electromagnetically induced transparency in atomic gases or doped ionic crystals operated at temperatures below 4K. Using a semi

  8. THE RED NOVA-LIKE VARIABLE IN M31-A BLUE CANDIDATE IN QUIESCENCE

    International Nuclear Information System (INIS)

    Shara, Michael M.; Zurek, David; Prialnik, Dina; Yaron, Ofer; Kovetz, Attay

    2010-01-01

    M31-RV was an extraordinarily luminous (∼10 6 L sun ) eruptive variable, displaying very cool temperatures (roughly 1000 K) as it faded. While this object's peak luminosity matched or exceeded those of the brightest known classical novae, its red colors and cool spectra were very different from those of classical novae. The photometric behavior of M31-RV (and several other very red novae, i.e., luminous eruptive red variables) has led to several models of this apparently new class of astrophysical object. We list these models, which predict very red eruptions and very red remnants decades after the eruptions. One of the most detailed models is that of 'mergebursts'. Mergebursts are (hypothetical) mergers of close binary stars, predicted to rival or exceed the brightest classical novae in luminosity, but to be much cooler and redder than classical novae, and to become slowly hotter and bluer as they age. This prediction suggests two stringent and definitive tests of the mergeburst hypothesis. First, there should always be a cool red remnant, and NOT a hot blue remnant at the site of such an outburst. Second, the inflated envelope of a mergeburst event should be slowly contracting; hence, it must display a slowly rising effective temperature. We have searched the location of M31-RV in multiple observatory archives. Our search revealed a luminous, UV-bright object within 0.''4 (1.5σ of the astrometric position) of M31-RV in archival WFPC2 images taken 10 years after the outburst. Recent Hubble imagery, 20 years after the outburst, determines that this object is still hot and fading; it remains much too hot to be a mergeburst. Furthermore, the effective temperature of this object is declining, contrary to the prediction for mergebursts. If we have correctly identified M31-RV's remnant, it cannot be a mergeburst-but its behavior is consistent with theoretical nova models which erupt on a low-mass white dwarf. Future Hubble UV and visible images could determine if the

  9. Variability in the carbon storage of seagrass habitats and its implications for global estimates of blue carbon ecosystem service.

    Directory of Open Access Journals (Sweden)

    Paul S Lavery

    Full Text Available The recent focus on carbon trading has intensified interest in 'Blue Carbon'-carbon sequestered by coastal vegetated ecosystems, particularly seagrasses. Most information on seagrass carbon storage is derived from studies of a single species, Posidonia oceanica, from the Mediterranean Sea. We surveyed 17 Australian seagrass habitats to assess the variability in their sedimentary organic carbon (C org stocks. The habitats encompassed 10 species, in mono-specific or mixed meadows, depositional to exposed habitats and temperate to tropical habitats. There was an 18-fold difference in the Corg stock (1.09-20.14 mg C org cm(-3 for a temperate Posidonia sinuosa and a temperate, estuarine P. australis meadow, respectively. Integrated over the top 25 cm of sediment, this equated to an areal stock of 262-4833 g C org m(-2. For some species, there was an effect of water depth on the C org stocks, with greater stocks in deeper sites; no differences were found among sub-tidal and inter-tidal habitats. The estimated carbon storage in Australian seagrass ecosystems, taking into account inter-habitat variability, was 155 Mt. At a 2014-15 fixed carbon price of A$25.40 t(-1 and an estimated market price of $35 t(-1 in 2020, the C org stock in the top 25 cm of seagrass habitats has a potential value of $AUD 3.9-5.4 bill. The estimates of annual C org accumulation by Australian seagrasses ranged from 0.093 to 6.15 Mt, with a most probable estimate of 0.93 Mt y(-1 (10.1 t. km(-2 y(-1. These estimates, while large, were one-third of those that would be calculated if inter-habitat variability in carbon stocks were not taken into account. We conclude that there is an urgent need for more information on the variability in seagrass carbon stock and accumulation rates, and the factors driving this variability, in order to improve global estimates of seagrass Blue Carbon storage.

  10. Climate Change Impact on Variability of Rainfall Intensity in Upper Blue Nile Basin, Ethiopia

    Science.gov (United States)

    Worku, L. Y.

    2015-12-01

    Extreme rainfall events are major problems in Ethiopia with the resulting floods that usually could cause significant damage to agriculture, ecology, infrastructure, disruption to human activities, loss of property, loss of lives and disease outbreak. The aim of this study was to explore the likely changes of precipitation extreme changes due to future climate change. The study specifically focuses to understand the future climate change impact on variability of rainfall intensity-duration-frequency in Upper Blue Nile basin. Precipitations data from two Global Climate Models (GCMs) have been used in the study are HadCM3 and CGCM3. Rainfall frequency analysis was carried out to estimate quantile with different return periods. Probability Weighted Method (PWM) selected estimation of parameter distribution and L-Moment Ratio Diagrams (LMRDs) used to find the best parent distribution for each station. Therefore, parent distributions for derived from frequency analysis are Generalized Logistic (GLOG), Generalized Extreme Value (GEV), and Gamma & Pearson III (P3) parent distribution. After analyzing estimated quantile simple disaggregation model was applied in order to find sub daily rainfall data. Finally the disaggregated rainfall is fitted to find IDF curve and the result shows in most parts of the basin rainfall intensity expected to increase in the future. As a result of the two GCM outputs, the study indicates there will be likely increase of precipitation extremes over the Blue Nile basin due to the changing climate. This study should be interpreted with caution as the GCM model outputs in this part of the world have huge uncertainty.

  11. Spectral characterisation of aperiodic normal-incidence Sb/B4C multilayer mirrors for the λ < 124 Å range

    Science.gov (United States)

    Vishnyakov, E. A.; Kopylets, I. A.; Kondratenko, V. V.; Kolesnikov, A. O.; Pirozhkov, A. S.; Ragozin, E. N.; Shatokhin, A. N.

    2018-03-01

    Three broadband aperiodic Sb/B4C multilayer mirrors were synthesised for the purposes of soft X-ray optics and spectroscopy in the wavelength range beyond the L-edge of Si (λ plasma radiation source and an electronic detector with a 2D spatial resolution (a CCD matrix with 13 × 13 μm sized pixels). The experimental spectra are compared with theoretical calculations. The effect of lower antimony and B4C layer densities on the reflection spectra is discussed.

  12. Tunneling in quantum superlattices with variable lacunarity

    Energy Technology Data Exchange (ETDEWEB)

    Villatoro, Francisco R. [Departamento de Lenguajes y Ciencias de la Computacion, Universidad de Malaga, E-29071 Malaga (Spain); Monsoriu, Juan A. [Departamento de Fisica Aplicada, Universidad Politecnica de Valencia, E-46022 Valencia (Spain)], E-mail: jmonsori@fis.upv.es

    2008-05-19

    Fractal superlattices are composite, aperiodic structures comprised of alternating layers of two semiconductors following the rules of a fractal set. The scattering properties of polyadic Cantor fractal superlattices with variable lacunarity are determined. The reflection coefficient as a function of the particle energy and the lacunarity parameter present tunneling curves, which may be classified as vertical, arc, and striation nulls. Approximate analytical formulae for such curves are derived using the transfer matrix method. Comparison with numerical results shows good accuracy. The new results may be useful in the development of band-pass energy filters for electrons, semiconductor solar cells, and solid-state radiation sources up to THz frequencies.

  13. Organizational justice is related to heart rate variability in white-collar workers, but not in blue-collar workers-findings from a cross-sectional study.

    Science.gov (United States)

    Herr, Raphael M; Bosch, Jos A; van Vianen, Annelies E M; Jarczok, Marc N; Thayer, Julian F; Li, Jian; Schmidt, Burkhard; Fischer, Joachim E; Loerbroks, Adrian

    2015-06-01

    Perceived injustice at work predicts coronary heart disease. Vagal dysregulation represents a potential psychobiological pathway. We examined associations between organizational justice and heart rate variability (HRV) indicators. Grounded in social exchange and psychological contract theory, we tested predictions that these associations are more pronounced among white-collar than among blue-collar workers. Cross-sectional data from 222 blue-collar and 179 white-collar men were used. Interactional and procedural justice were measured by questionnaire. Ambulatory HRV was assessed across 24 h. Standardized regression coefficients (β) were calculated. Among white-collar workers, interactional justice showed positive relationships with 24-h HRV, which were strongest during sleeping time (adjusted βs≥0.26; p values≤0.01). No associations were found for blue-collar workers. A comparable but attenuated pattern was observed for procedural justice. Both dimensions of organizational injustice were associated with lowered HRV among white-collar workers. The impact of justice and possibly its association with health seems to differ by occupational groups.

  14. Design of an amplifier model accounting for thermal effect in fully aperiodic large pitch fibers

    Science.gov (United States)

    Tragni, K.; Molardi, C.; Poli, F.; Dauliat, R.; Leconte, B.; Darwich, D.; du Jeu, R.; Malleville, M. A.; Jamier, R.; Selleri, S.; Roy, P.; Cucinotta, A.

    2018-02-01

    Yb-doped Photonic Crystal Fibers (PCFs) have triggered a significant power scaling into fiber-based lasers. However thermally-induced effects, like mode instability, can compromise the output beam quality. PCF design with improved Higher Order Mode (HOM) delocalization and effective thermal resilience can contain the problem. In particular, Fully- Aperiodic Large-Pitch Fibers (FA-LPFs) have shown interesting properties in terms of resilience to thermal effects. In this paper the performances of a Yb-doped FA-LPF amplifier are experimentally and numerically investigated. Modal properties and gain competition between Fundamental Mode (FM) and first HOM have been calculated, in presence of thermal effects. The main doped fiber characteristics have been derived by comparison between experimental and numerical results.

  15. Assessment of AOD variability over Saudi Arabia using MODIS Deep Blue products

    International Nuclear Information System (INIS)

    Butt, Mohsin Jamil; Assiri, Mazen Ebraheem; Ali, Md. Arfan

    2017-01-01

    The aim of this study is to investigate the variability of aerosol over The Kingdom of Saudi Arabia. For this analysis, Moderate Resolution Imaging Spectroradiometer (MODIS) Deep Blue (DB) Aerosol Optical Depth (AOD) product from Terra and Aqua satellites for the years 2000–2013 is used. The product is validated using AERONET data from ground stations, which are situated at Solar Village Riyadh and King Abdullah University of Science and Technology (KAUST) Jeddah. The results show that both Terra and Aqua satellites exhibit a tendency to show the spatial variation of AOD with Aqua being better than Terra to represent the ground based AOD measurements over the study region. The results also show that the eastern, central, and southern regions of the country have a high concentration of AOD during the study period. The validation results show the highest correlation coefficient between Aqua and KAUST data with a value of 0.79, whilst the Aqua and Solar Village based AOD indicates the lowest Root Mean Square Error (RMSE) and Mean Absolute Error (MAE) values which are, 0.17 and 0.12 respectively. Furthermore, the Relative Mean Bias (RMB) based analysis show that the DB algorithm overestimates the AOD when using Terra and Solar Village data, while it underestimates the AOD when using Aqua with Solar Village and KAUST data. The RMB value for Aqua and Solar Village data indicates that the DB algorithm is close to normal in the study region. - Highlights: • The significance of aerosol in the Kingdom of Saudi Arabia is addressed. • MODIS (Terra and Aqua), AERONET and ground based sand event data is used. • MODIS DB product is used to prepare annual aerosol maps and monthly AOD variability. • A comparison is made between Terra and Aqua AOD product over bright surface. • MODIS DB AOD product is validated using AERONET data at Solar Village and KAUST. - This research highlighted the aerosol variability over The Kingdom of Saudi Arabia by using Satellite, AERONET

  16. The Pagoda Sequence: a Ramble through Linear Complexity, Number Walls, D0L Sequences, Finite State Automata, and Aperiodic Tilings

    Directory of Open Access Journals (Sweden)

    Fred Lunnon

    2009-06-01

    Full Text Available We review the concept of the number wall as an alternative to the traditional linear complexity profile (LCP, and sketch the relationship to other topics such as linear feedback shift-register (LFSR and context-free Lindenmayer (D0L sequences. A remarkable ternary analogue of the Thue-Morse sequence is introduced having deficiency 2 modulo 3, and this property verified via the re-interpretation of the number wall as an aperiodic plane tiling.

  17. Broad-Band Variability in Accreting Compact Objects

    Directory of Open Access Journals (Sweden)

    S. Scaringi

    2015-02-01

    Full Text Available Cataclysmic variable stars are in many ways similar to X-ray binaries. Both types of systems possess an accretion disk, which in most cases can reach the surface (or event horizon of the central compact object. The main difference is that the embedded gravitational potential well in X-ray binaries is much deeper than those found in cataclysmic variables. As a result, X-ray binaries emit most of their radiation at X-ray wavelengths, as opposed to cataclysmic variables which emit mostly at optical/ultraviolet wavelengths. Both types of systems display aperiodic broad-band variability which can be associated to the accretion disk. Here, the properties of the observed X-ray variability in XRBs are compared to those observed at optical wavelengths in CVs. In most cases the variability properties of both types of systems are qualitatively similar once the relevant timescales associated with the inner accretion disk regions have been taken into account. The similarities include the observed power spectral density shapes, the rms-flux relation as well as Fourier-dependant time lags. Here a brief overview on these similarities is given, placing them in the context of the fluctuating accretion disk model which seeks to reproduce the observed variability.

  18. Short-term variability and mass loss in Be stars. II. Physical taxonomy of photometric variability observed by the Kepler spacecraft

    Science.gov (United States)

    Rivinius, Th.; Baade, D.; Carciofi, A. C.

    2016-09-01

    Context. Classical Be stars have been established as pulsating stars. Space-based photometric monitoring missions contributed significantly to that result. However, whether Be stars are just rapidly rotating SPB or β Cep stars, or whether they have to be understood differently, remains debated in the view of their highly complex power spectra. Aims: Kepler data of three known Be stars are re-visited to establish their pulsational nature and assess the properties of additional, non-pulsational variations. The three program stars turned out to be one inactive Be star, one active, continuously outbursting Be star, and one Be star transiting from a non-outbursting into an outbursting phase, thus forming an excellent sample to distill properties of Be stars in the various phases of their life-cycle. Methods: The Kepler data was first cleaned from any long-term variability with Lomb-Scargle based pre-whitening. Then a Lomb-Scargle analysis of the remaining short-term variations was compared to a wavelet analysis of the cleaned data. This offers a new view on the variability, as it enables us to see the temporal evolution of the variability and phase relations between supposed beating phenomena, which are typically not visualized in a Lomb-Scargle analysis. Results: The short-term photometric variability of Be stars must be disentangled into a stellar and a circumstellar part. The stellar part is on the whole not different from what is seen in non-Be stars. However, some of the observed phenomena might be to be due to resonant mode coupling, a mechanism not typically considered for B-type stars. Short-term circumstellar variability comes in the form of either a group of relatively well-defined, short-lived frequencies during outbursts, which are called Štefl frequencies, and broad bumps in the power spectra, indicating aperiodic variability on a time scale similar to typical low-order g-mode pulsation frequencies, rather than true periodicity. Conclusions: From a

  19. The Search for New Luminous Blue Variable Stars: Near-Infrared Spectroscopy of Stars With 24 micron Shells

    Science.gov (United States)

    Stringfellow, Guy; Gvaramadze, Vasilii

    2010-02-01

    Luminous Blue Variable (LBV) stars represent an extremely rare class of very luminous and massive stars. Only about a dozen confirmed Galactic LBV stars are known to date, which precludes us from determining a solid evolutionary connection between LBV and other intermediate (e.g. Ofpe/WN9, WNL) phases in the life of very massive stars. The known LBV stars each have their own unique properties, so new discoveries add insight into the properties and evolutionary status of LBVs and massive stars; even one new discovery of objects of this type could provide break-through results in the understanding of the intermediate stages of massive star evolution. We have culled a prime sample of possible LBV candidates from the Spitzer 24 (micron) archival data. All have circumstellar nebulae, rings, and shells (typical of LBVs and related stars) surrounding reddened central stars. Spectroscopic followup of about two dozen optically visible central stars associated with the shells from this sample showed that they are either candidate LBVs, late WN-type Wolf-Rayet stars or blue supergiants. We propose infrared spectroscopic observations of the central stars for a large fraction (23 stars) of our northern sample to determine their nature and discover additional LBV candidates. These stars have no plausible optical counterparts, so infrared spectra are needed. This program requires two nights of Hale time using TripleSpec.

  20. An ultraviolet study of B[e] stars: evidence for pulsations, luminous blue variable type variations and processes in envelopes

    Science.gov (United States)

    Krtičková, I.; Krtička, J.

    2018-06-01

    Stars that exhibit a B[e] phenomenon comprise a very diverse group of objects in a different evolutionary status. These objects show common spectral characteristics, including the presence of Balmer lines in emission, forbidden lines and strong infrared excess due to dust. Observations of emission lines indicate illumination by an ultraviolet ionizing source, which is key to understanding the elusive nature of these objects. We study the ultraviolet variability of many B[e] stars to specify the geometry of the circumstellar environment and its variability. We analyse massive hot B[e] stars from our Galaxy and from the Magellanic Clouds. We study the ultraviolet broad-band variability derived from the flux-calibrated data. We determine variations of individual lines and the correlation with the total flux variability. We detected variability of the spectral energy distribution and of the line profiles. The variability has several sources of origin, including light absorption by the disc, pulsations, luminous blue variable type variations, and eclipses in the case of binaries. The stellar radiation of most of B[e] stars is heavily obscured by circumstellar material. This suggests that the circumstellar material is present not only in the disc but also above its plane. The flux and line variability is consistent with a two-component model of a circumstellar environment composed of a dense disc and an ionized envelope. Observations of B[e] supergiants show that many of these stars have nearly the same luminosity, about 1.9 × 105 L⊙, and similar effective temperatures.

  1. Application of the three-dimensional aperiodic Fourier modal method using arc elements in curvilinear coordinates.

    Science.gov (United States)

    Bucci, Davide; Martin, Bruno; Morand, Alain

    2012-03-01

    This paper deals with a full vectorial generalization of the aperiodic Fourier modal method (AFMM) in cylindrical coordinates. The goal is to predict some key characteristics such as the bending losses of waveguides having an arbitrary distribution of the transverse refractive index. After a description of the method, we compare the results of the cylindrical coordinates AFMM with simulations by the finite-difference time-domain (FDTD) method performed on an S-bend structure made by a 500 nm × 200 nm silicon core (n=3.48) in silica (n=1.44) at a wavelength λ=1550 nm, the bending radius varying from 0.5 up to 2 μm. The FDTD and AFMM results show differences comparable to the variations obtained by changing the parameters of the FDTD simulations.

  2. Statistical thermodynamics of supercapacitors and blue engines

    NARCIS (Netherlands)

    van Roij, R.H.H.G.

    2013-01-01

    We study the thermodynamics of electrode-electrolyte systems, for instance supercapacitors filled with an ionic liquid or blue-energy devices filled with river- or sea water. By a suitable mapping of thermodynamic variables, we identify a strong analogy with classical heat engines. We introduce

  3. Aperiodic dynamics in a deterministic adaptive network model of attitude formation in social groups

    Science.gov (United States)

    Ward, Jonathan A.; Grindrod, Peter

    2014-07-01

    Adaptive network models, in which node states and network topology coevolve, arise naturally in models of social dynamics that incorporate homophily and social influence. Homophily relates the similarity between pairs of nodes' states to their network coupling strength, whilst social influence causes coupled nodes' states to convergence. In this paper we propose a deterministic adaptive network model of attitude formation in social groups that includes these effects, and in which the attitudinal dynamics are represented by an activato-inhibitor process. We illustrate that consensus, corresponding to all nodes adopting the same attitudinal state and being fully connected, may destabilise via Turing instability, giving rise to aperiodic dynamics with sensitive dependence on initial conditions. These aperiodic dynamics correspond to the formation and dissolution of sub-groups that adopt contrasting attitudes. We discuss our findings in the context of cultural polarisation phenomena. Social influence. This reflects the fact that people tend to modify their behaviour and attitudes in response to the opinions of others [22-26]. We model social influence via diffusion: agents adjust their state according to a weighted sum (dictated by the evolving network) of the differences between their state and the states of their neighbours. Homophily. This relates the similarity of individuals' states to their frequency and strength of interaction [27]. Thus in our model, homophily drives the evolution of the weighted ‘social' network. A precise formulation of our model is given in Section 2. Social influence and homophily underpin models of social dynamics [21], which cover a wide range of sociological phenomena, including the diffusion of innovations [28-32], complex contagions [33-36], collective action [37-39], opinion dynamics [19,20,40,10,11,13,15,41,16], the emergence of social norms [42-44], group stability [45], social differentiation [46] and, of particular relevance

  4. Time variability of X-ray binaries: observations with INTEGRAL. Modeling

    International Nuclear Information System (INIS)

    Cabanac, Clement

    2007-01-01

    The exact origin of the observed X and Gamma ray variability in X-ray binaries is still an open debate in high energy astrophysics. Among others, these objects are showing aperiodic and quasi-periodic luminosity variations on timescales as small as the millisecond. This erratic behavior must put constraints on the proposed emission processes occurring in the vicinity of the neutrons star or the stellar mass black-hole held by these objects. We propose here to study their behavior following 3 different ways: first we examine the evolution of a particular X-ray source discovered by INTEGRAL, IGR J19140+0951. Using timing and spectral data given by different instruments, we show that the source type is plausibly consistent with a High Mass X-ray Binary hosting a neutrons star. Subsequently, we propose a new method dedicated to the study of timing data coming from coded mask aperture instruments. Using it on INTEGRAL/ISGRI real data, we detect the presence of periodic and quasi-periodic features in some pulsars and micro-quasars at energies as high as a hundred keV. Finally, we suggest a model designed to describe the low frequency variability of X-ray binaries in their hardest state. This model is based on thermal comptonization of soft photons by a warm corona in which a pressure wave is propagating in cylindrical geometry. By computing both numerical simulations and analytical solution, we show that this model should be suitable to describe some of the typical features observed in X-ray binaries power spectra in their hard state and their evolution such as aperiodic noise and low frequency quasi-periodic oscillations. (author) [fr

  5. Modelling the effects of environmental conditions on the acoustic occurrence and behaviour of Antarctic blue whales.

    Directory of Open Access Journals (Sweden)

    Fannie W Shabangu

    Full Text Available Harvested to perilously low numbers by commercial whaling during the past century, the large scale response of Antarctic blue whales Balaenoptera musculus intermedia to environmental variability is poorly understood. This study uses acoustic data collected from 586 sonobuoys deployed in the austral summers of 1997 through 2009, south of 38°S, coupled with visual observations of blue whales during the IWC SOWER line-transect surveys. The characteristic Z-call and D-call of Antarctic blue whales were detected using an automated detection template and visual verification method. Using a random forest model, we showed the environmental preferences pattern, spatial occurrence and acoustic behaviour of Antarctic blue whales. Distance to the southern boundary of the Antarctic Circumpolar Current (SBACC, latitude and distance from the nearest Antarctic shores were the main geographic predictors of blue whale call occurrence. Satellite-derived sea surface height, sea surface temperature, and productivity (chlorophyll-a were the most important environmental predictors of blue whale call occurrence. Call rates of D-calls were strongly predicted by the location of the SBACC, latitude and visually detected number of whales in an area while call rates of Z-call were predicted by the SBACC, latitude and longitude. Satellite-derived sea surface height, wind stress, wind direction, water depth, sea surface temperatures, chlorophyll-a and wind speed were important environmental predictors of blue whale call rates in the Southern Ocean. Blue whale call occurrence and call rates varied significantly in response to inter-annual and long term variability of those environmental predictors. Our results identify the response of Antarctic blue whales to inter-annual variability in environmental conditions and highlighted potential suitable habitats for this population. Such emerging knowledge about the acoustic behaviour, environmental and habitat preferences of

  6. Modelling the effects of environmental conditions on the acoustic occurrence and behaviour of Antarctic blue whales.

    Science.gov (United States)

    Shabangu, Fannie W; Yemane, Dawit; Stafford, Kathleen M; Ensor, Paul; Findlay, Ken P

    2017-01-01

    Harvested to perilously low numbers by commercial whaling during the past century, the large scale response of Antarctic blue whales Balaenoptera musculus intermedia to environmental variability is poorly understood. This study uses acoustic data collected from 586 sonobuoys deployed in the austral summers of 1997 through 2009, south of 38°S, coupled with visual observations of blue whales during the IWC SOWER line-transect surveys. The characteristic Z-call and D-call of Antarctic blue whales were detected using an automated detection template and visual verification method. Using a random forest model, we showed the environmental preferences pattern, spatial occurrence and acoustic behaviour of Antarctic blue whales. Distance to the southern boundary of the Antarctic Circumpolar Current (SBACC), latitude and distance from the nearest Antarctic shores were the main geographic predictors of blue whale call occurrence. Satellite-derived sea surface height, sea surface temperature, and productivity (chlorophyll-a) were the most important environmental predictors of blue whale call occurrence. Call rates of D-calls were strongly predicted by the location of the SBACC, latitude and visually detected number of whales in an area while call rates of Z-call were predicted by the SBACC, latitude and longitude. Satellite-derived sea surface height, wind stress, wind direction, water depth, sea surface temperatures, chlorophyll-a and wind speed were important environmental predictors of blue whale call rates in the Southern Ocean. Blue whale call occurrence and call rates varied significantly in response to inter-annual and long term variability of those environmental predictors. Our results identify the response of Antarctic blue whales to inter-annual variability in environmental conditions and highlighted potential suitable habitats for this population. Such emerging knowledge about the acoustic behaviour, environmental and habitat preferences of Antarctic blue whales is

  7. The Blue Compact Dwarf Galaxy IZw18

    NARCIS (Netherlands)

    Musella, I.; Marconi, M.; Fiorentino, G.; Clementini, G.; Aloisi, A.; Annibali, F.; Contreras, R.; Saha, A.; Tosi, M.; van der Marel, R. P.

    2012-01-01

    We present the results obtained for the Blue compact galaxy IZw18 on the basis of ACS HST data obtained from our group. In particular, we discuss the stellar population and the variable stars content of this galaxy to get information about its star formation history and distance.

  8. Inter-Annual Variability in Blue Whale Distribution off Southern Sri Lanka between 2011 and 2012

    OpenAIRE

    Vos, Asha de; Pattiaratchi, Charitha; Harcourt, Robert

    2014-01-01

    Blue whale (Balaenoptera musculus) movements are often driven by the availability of their prey in space and time. While globally blue whale populations undertake long-range migrations between feeding and breeding grounds, those in the northern Indian Ocean remain in low latitude waters throughout the year with the implication that the productivity of these waters is sufficient to support their energy needs. A part of this population remains around Sri Lanka where they are usually recorded cl...

  9. Blue mussel shell shape plasticity and natural environments: a quantitative approach

    DEFF Research Database (Denmark)

    Telesca, Luca; Michalek, Kati; Sanders, Trystan

    2018-01-01

    Shape variability represents an important direct response of organisms to selective environments. Here, we use a combination of geometric morphometrics and generalised additive mixed models (GAMMs) to identify spatial patterns of natural shell shape variation in the North Atlantic and Arctic blue...... scales analysed. Our results show how shell shape plasticity represents a powerful indicator to understand the alterations of blue mussel communities in rapidly changing environments....

  10. The Time Is Up: Compression of Visual Time Interval Estimations of Bimodal Aperiodic Patterns

    Science.gov (United States)

    Duarte, Fabiola; Lemus, Luis

    2017-01-01

    The ability to estimate time intervals subserves many of our behaviors and perceptual experiences. However, it is not clear how aperiodic (AP) stimuli affect our perception of time intervals across sensory modalities. To address this question, we evaluated the human capacity to discriminate between two acoustic (A), visual (V) or audiovisual (AV) time intervals of trains of scattered pulses. We first measured the periodicity of those stimuli and then sought for correlations with the accuracy and reaction times (RTs) of the subjects. We found that, for all time intervals tested in our experiment, the visual system consistently perceived AP stimuli as being shorter than the periodic (P) ones. In contrast, such a compression phenomenon was not apparent during auditory trials. Our conclusions are: first, the subjects exposed to P stimuli are more likely to measure their durations accurately. Second, perceptual time compression occurs for AP visual stimuli. Lastly, AV discriminations are determined by A dominance rather than by AV enhancement. PMID:28848406

  11. A novel scenario of aperiodical impacts appearance in the turbine draft tube

    Science.gov (United States)

    Alekseenko, S. V.; Kuibin, P. A.; Shtork, S. I.; Skripkin, S. G.; Sonin, V. I.; Tsoy, M. A.; Ustimenko, A. S.

    2016-11-01

    The swirling flow in the discharge cone of hydroturbine is characterized by various self-induced instabilities and associated low frequency phenomena when the turbine is operated far from the best efficiency point. In particular, the precessing vortex rope develops at part-load regimes in the draft tube. This rope can serve a reason of the periodical low- frequency pressure oscillations in the whole hydrodynamical system. During the experimental research of flow structure in the discharge cone in a regime of free runner new interesting phenomenon was discovered. Due to instability some coils of helical vortex close to each other and reconnection appears with generation of a vortex ring. The experiments were fulfilled at the cavitational conditions when a cavity arises in the vortex core. So the phenomenon was registered with help of visualization by the high speed video recording. The vortex ring after the reconnection moves apart from the main vortex rope toward the wall and downstream. When it reaches the area with high pressure the cavity collapses with generation of pressure impact. The mechanism of cavitational vortex rings generation and their further collapse can serve as a prototype of the aperiodical pressure impacts inside the turbine draft tube.

  12. Stochastic resonance in a bistable system subject to multi-time-delayed feedback and aperiodic signal

    International Nuclear Information System (INIS)

    Li Jianlong; Zeng Lingzao

    2010-01-01

    We discuss in detail the effects of the multi-time-delayed feedback driven by an aperiodic signal on the output of a stochastic resonance (SR) system. The effective potential function and dynamical probability density function (PDF) are derived. To measure the performance of the SR system in the presence of a binary random signal, the bit error rate (BER) defined by the dynamical PDF is employed, as is commonly used in digital communications. We find that the delay time, strength of the feedback, and number of time-delayed terms can change the effective potential function and the effective amplitude of the signal, and then affect the BER of the SR system. The numerical simulations strongly support the theoretical results. The goal of this investigation is to explore the effects of the multi-time-delayed feedback on SR and give a guidance to nonlinear systems in the application of information processing.

  13. Outflow-Induced Dynamical and Radiative Instability in Stellar Envelopes with an Application to Luminous Blue Variables and Wolf-Rayet Stars

    Science.gov (United States)

    Stothers, Richard B.; Hansen, James E. (Technical Monitor)

    2002-01-01

    Theoretical models of the remnants of massive stars in a very hot, post-red-supergiant phase display no obvious instability if standard assumptions are made. However, the brightest observed classical luminous blue variables (LBVs) may well belong to such a phase. A simple time-dependent theory of moving stellar envelopes is developed in order to treat deep hydrodynamical disturbances caused by surface mass loss and to test the moving envelopes for dynamical instability. In the case of steady-state outflow, the theory reduces to the equivalent of the Castor, Abbott, and Klein formulation for optically thick winds at distances well above the sonic point. The time-dependent version indicates that the brightest and hottest LBVs are both dynamically and radiatively unstable, as a result of the substantial lowering of the generalized Eddington luminosity limit by the mass-loss acceleration. It is suggested that dynamical instability, by triggering secular cycles of mass loss, is primarily what differentiates LBVs from the purely radiatively unstable Wolf-Rayet stars. Furthermore, when accurate main-sequence mass-loss rates are used to calculate the evolutionary tracks, the predicted surface hydrogen and nitrogen abundances of the blue remnants agree much better with observations of the brightest LBVs than before.

  14. Age-class separation of blue-winged ducks

    Science.gov (United States)

    Hohman, W.L.; Moore, J.L.; Twedt, D.J.; Mensik, John G.; Logerwell, E.

    1995-01-01

    and flyway differences in remigial measurements and reduced performance of age classification models as evidence of high variability in size of blue-winged ducks' remiges. Variability in remigial size of these and other small-bodied waterfowl may be related to nutrition during molt.

  15. High-luminosity blue and blue-green gallium nitride light-emitting diodes.

    Science.gov (United States)

    Morkoç, H; Mohammad, S N

    1995-01-06

    Compact and efficient sources of blue light for full color display applications and lighting eluded and tantalized researchers for many years. Semiconductor light sources are attractive owing to their reliability and amenability to mass manufacture. However, large band gaps are required to achieve blue color. A class of compound semiconductors formed by metal nitrides, GaN and its allied compounds AIGaN and InGaN, exhibits properties well suited for not only blue and blue-green emitters, but also for ultraviolet emitters and detectors. What thwarted engineers and scientists from fabricating useful devices from these materials in the past was the poor quality of material and lack of p-type doping. Both of these obstacles have recently been overcome to the point where highluminosity blue and blue-green light-emitting diodes are now available in the marketplace.

  16. Blue ocean strategy.

    Science.gov (United States)

    Kim, W Chan; Mauborgne, Renée

    2004-10-01

    Despite a long-term decline in the circus industry, Cirque du Soleil profitably increased revenue 22-fold over the last ten years by reinventing the circus. Rather than competing within the confines of the existing industry or trying to steal customers from rivals, Cirque developed uncontested market space that made the competition irrelevant. Cirque created what the authors call a blue ocean, a previously unknown market space. In blue oceans, demand is created rather than fought over. There is ample opportunity for growth that is both profitable and rapid. In red oceans--that is, in all the industries already existing--companies compete by grabbing for a greater share of limited demand. As the market space gets more crowded, prospects for profits and growth decline. Products turn into commodities, and increasing competition turns the water bloody. There are two ways to create blue oceans. One is to launch completely new industries, as eBay did with online auctions. But it's much more common for a blue ocean to be created from within a red ocean when a company expands the boundaries of an existing industry. In studying more than 150 blue ocean creations in over 30 industries, the authors observed that the traditional units of strategic analysis--company and industry--are of limited use in explaining how and why blue oceans are created. The most appropriate unit of analysis is the strategic move, the set of managerial actions and decisions involved in making a major market-creating business offering. Creating blue oceans builds brands. So powerful is blue ocean strategy, in fact, that a blue ocean strategic move can create brand equity that lasts for decades.

  17. Electronic properties of blue phosphorene/graphene and blue phosphorene/graphene-like gallium nitride heterostructures.

    Science.gov (United States)

    Sun, Minglei; Chou, Jyh-Pin; Yu, Jin; Tang, Wencheng

    2017-07-05

    Blue phosphorene (BlueP) is a graphene-like phosphorus nanosheet which was synthesized very recently for the first time [Nano Lett., 2016, 16, 4903-4908]. The combination of electronic properties of two different two-dimensional materials in an ultrathin van der Waals (vdW) vertical heterostructure has been proved to be an effective approach to the design of novel electronic and optoelectronic devices. Therefore, we used density functional theory to investigate the structural and electronic properties of two BlueP-based heterostructures - BlueP/graphene (BlueP/G) and BlueP/graphene-like gallium nitride (BlueP/g-GaN). Our results showed that the semiconducting nature of BlueP and the Dirac cone of G are well preserved in the BlueP/G vdW heterostructure. Moreover, by applying a perpendicular electric field, it is possible to tune the position of the Dirac cone of G with respect to the band edge of BlueP, resulting in the ability to control the Schottky barrier height. For the BlueP/g-GaN vdW heterostructure, BlueP forms an interface with g-GaN with a type-II band alignment, which is a promising feature for unipolar electronic device applications. Furthermore, we discovered that both G and g-GaN can be used as an active layer for BlueP to facilitate charge injection and enhance the device performance.

  18. MN48: a new Galactic bona fide luminous blue variable revealed by Spitzer and SALT

    Science.gov (United States)

    Kniazev, A. Y.; Gvaramadze, V. V.; Berdnikov, L. N.

    2016-07-01

    In this paper, we report the results of spectroscopic and photometric observations of the candidate evolved massive star MN48 disclosed via detection of a mid-infrared circular shell around it with the Spitzer Space Telescope. Follow-up optical spectroscopy of MN48 with the Southern African Large Telescope (SALT) carried out in 2011-2015 revealed significant changes in the spectrum of this star, which are typical of luminous blue variables (LBVs). The LBV status of MN48 was further supported by photometric monitoring which shows that in 2009-2011 this star has brightened by ≈0.9 and 1 mag in the V and Ic bands, respectively, then faded by ≈1.1 and 1.6 mag during the next four years, and apparently started to brighten again recently. The detected changes in the spectrum and brightness of MN48 make this star the 18th known Galactic bona fide LBV and increase the percentage of LBVs associated with circumstellar nebulae to more than 70 per cent. We discuss the possible birth place of MN48 and suggest that this star might have been ejected either from a putative star cluster embedded in the H II region IRAS 16455-4531 or the young massive star cluster Westerlund 1.

  19. A complex approach to the blue-loop problem

    Science.gov (United States)

    Ostrowski, Jakub; Daszynska-Daszkiewicz, Jadwiga

    2015-08-01

    The problem of the blue loops during the core helium burning, outstanding for almost fifty years, is one of the most difficult and poorly understood problems in stellar astrophysics. Most of the work focused on the blue loops done so far has been performed with old stellar evolution codes and with limited computational resources. In the end the obtained conclusions were based on a small sample of models and could not have taken into account more advanced effects and interactions between them.The emergence of the blue loops depends on many details of the evolution calculations, in particular on chemical composition, opacity, mixing processes etc. The non-linear interactions between these factors contribute to the statement that in most cases it is hard to predict without a precise stellar modeling whether a loop will emerge or not. The high sensitivity of the blue loops to even small changes of the internal structure of a star yields one more issue: a sensitivity to numerical problems, which are common in calculations of stellar models on advanced stages of the evolution.To tackle this problem we used a modern stellar evolution code MESA. We calculated a large grid of evolutionary tracks (about 8000 models) with masses in the range of 3.0 - 25.0 solar masses from the zero age main sequence to the depletion of helium in the core. In order to make a comparative analysis, we varied metallicity, helium abundance and different mixing parameters resulting from convective overshooting, rotation etc.The better understanding of the properties of the blue loops is crucial for our knowledge of the population of blue supergiants or pulsating variables such as Cepheids, α-Cygni or Slowly Pulsating B-type supergiants. In case of more massive models it is also of great importance for studies of the progenitors of supernovae.

  20. Discovery of two new Galactic candidate luminous blue variables with Wide-field Infrared Survey Explorer

    Science.gov (United States)

    Gvaramadze, V. V.; Kniazev, A. Y.; Miroshnichenko, A. S.; Berdnikov, L. N.; Langer, N.; Stringfellow, G. S.; Todt, H.; Hamann, W.-R.; Grebel, E. K.; Buckley, D.; Crause, L.; Crawford, S.; Gulbis, A.; Hettlage, C.; Hooper, E.; Husser, T.-O.; Kotze, P.; Loaring, N.; Nordsieck, K. H.; O'Donoghue, D.; Pickering, T.; Potter, S.; Romero Colmenero, E.; Vaisanen, P.; Williams, T.; Wolf, M.; Reichart, D. E.; Ivarsen, K. M.; Haislip, J. B.; Nysewander, M. C.; LaCluyze, A. P.

    2012-04-01

    We report the discovery of two new Galactic candidate luminous blue variable (LBV) stars via detection of circular shells (typical of confirmed and candidate LBVs) and follow-up spectroscopy of their central stars. The shells were detected at 22 μm in the archival data of the Mid-Infrared All Sky Survey carried out with the Wide-field Infrared Survey Explorer (WISE). Follow-up optical spectroscopy of the central stars of the shells conducted with the renewed Southern African Large Telescope (SALT) showed that their spectra are very similar to those of the well-known LBVs P Cygni and AG Car, and the recently discovered candidate LBV MN112, which implies the LBV classification for these stars as well. The LBV classification of both stars is supported by detection of their significant photometric variability: one of them brightened in the R and I bands by 0.68 ± 0.10 and 0.61 ± 0.04 mag, respectively, during the last 13-18 years, while the second one (known as Hen 3-1383) varies its B, V, R, I and Ks brightnesses by ≃0.5-0.9 mag on time-scales from 10 d to decades. We also found significant changes in the spectrum of Hen 3-1383 on a time-scale of ≃3 months, which provides additional support for the LBV classification of this star. Further spectrophotometric monitoring of both stars is required to firmly prove their LBV status. We discuss a connection between the location of massive stars in the field and their fast rotation, and suggest that the LBV activity of the newly discovered candidate LBVs might be directly related to their possible runaway status. a USNO B-1 (Monet et al. 2003); bDENIS; c2MASS; dSALT; ePROMPT.

  1. Anomalous Cepheids and population II blue stragglers

    Science.gov (United States)

    Nemec, James M.

    Recent studies of anomalous Cepheids (ACs) and population II blue stragglers (BSs), including photometrically variable BSs (VBSs), are reviewed. The VBSs represent about 25 percent of the BSs, the majority of which are SX Phe short-period variables in the Cepheid instability strip. Mass estimates derived using various techniques suggest that both ACs and BSs are relatively massive (about 1.0-1.6 solar mass). The recent discovery that two BSs in the globular cluster NGC 5466 are contact binaries, and the earlier discovery that one of the BSs in Omega Cen is an eclipsing binary, provide direct evidence that at least some BSs are binary systems.

  2. Dermatoscopy of blue vitiligo.

    Science.gov (United States)

    Chandrashekar, L

    2009-07-01

    Blue vitiligo is a distinct variant of vitiligo characterized by a blue-grey appearance of the skin, which corresponds histologically with absence of epidermal melanocytes and presence of numerous dermal melanophages. A 23-year-old woman of Indian origin with Fitzpatrick skin type V presented with a 1-month history of normoaesthetic depigmented macules over the right forearm, dorsa of the hands and right areola. The macule over the right forearm had a bluish tinge. A clinical diagnosis of vitiligo vulgaris with blue vitiligo was made. Dermatoscopy of the interface between the blue macule and the hypopigmented macule revealed a linear depigmented macule in the centre with multiple blue dots and absence of epidermal melanin on the side of the blue macule, and reticular pigmentation with a few depigmented macules and scattered blue dots over the side of the hypopigmented macule. Blue vitiligo was described previously in a patient seropositive for human immunodeficiency virus, and believed to represent postinflammatory hyperpigmentation in areas bordering the vitiliginous patches as a result of psoralen ultraviolet A treatment. This case is unusual because of its rarity and the description of the associated dermatoscopical findings.

  3. Statistical thermodynamics of supercapacitors and blue engines

    OpenAIRE

    van Roij, René

    2012-01-01

    We study the thermodynamics of electrode-electrolyte systems, for instance supercapacitors filled with an ionic liquid or blue-energy devices filled with river- or sea water. By a suitable mapping of thermodynamic variables, we identify a strong analogy with classical heat engines. We introduce several Legendre transformations and Maxwell relations. We argue that one should distinguish between the differential capacity at constant ion number and at constant ion chemical potential, and derive ...

  4. Assessment of the impact of climate change on spatiotemporal variability of blue and green water resources under CMIP3 and CMIP5 models in a highly mountainous watershed

    Science.gov (United States)

    Fazeli Farsani, Iman; Farzaneh, M. R.; Besalatpour, A. A.; Salehi, M. H.; Faramarzi, M.

    2018-04-01

    The variability and uncertainty of water resources associated with climate change are critical issues in arid and semi-arid regions. In this study, we used the soil and water assessment tool (SWAT) to evaluate the impact of climate change on the spatial and temporal variability of water resources in the Bazoft watershed, Iran. The analysis was based on changes of blue water flow, green water flow, and green water storage for a future period (2010-2099) compared to a historical period (1992-2008). The r-factor, p-factor, R 2, and Nash-Sutcliff coefficients for discharge were 1.02, 0.89, 0.80, and 0.80 for the calibration period and 1.03, 0.76, 0.57, and 0.59 for the validation period, respectively. General circulation models (GCMs) under 18 emission scenarios from the IPCC's Fourth (AR4) and Fifth (AR5) Assessment Reports were fed into the SWAT model. At the sub-basin level, blue water tended to decrease, while green water flow tended to increase in the future scenario, and green water storage was predicted to continue its historical trend into the future. At the monthly time scale, the 95% prediction uncertainty bands (95PPUs) of blue and green water flows varied widely in the watershed. A large number (18) of climate change scenarios fell within the estimated uncertainty band of the historical period. The large differences among scenarios indicated high levels of uncertainty in the watershed. Our results reveal that the spatial patterns of water resource components and their uncertainties in the context of climate change are notably different between IPCC AR4 and AR5 in the Bazoft watershed. This study provides a strong basis for water supply-demand analyses, and the general analytical framework can be applied to other study areas with similar challenges.

  5. Origin of colour stability in blue/orange/blue stacked phosphorescent white organic light-emitting diodes

    International Nuclear Information System (INIS)

    Kim, Sung Hyun; Jang, Jyongsik; Yook, Kyoung Soo; Lee, Jun Yeob

    2009-01-01

    The origin of colour stability in phosphorescent white organic light-emitting diodes (PHWOLEDs) with a blue/orange/blue stacked emitting structure was studied by monitoring the change in a recombination zone. A balanced recombination zone shift between the blue and the orange light-emitting layers was found to be responsible for the colour stability in the blue/orange/blue stacked PHWOLEDs.

  6. Corneal edema and permanent blue discoloration of a silicone intraocular lens by methylene blue.

    Science.gov (United States)

    Stevens, Scott; Werner, Liliana; Mamalis, Nick

    2007-01-01

    To report a silicone intraocular lens (IOL) stained blue by inadvertent intraoperative use of methylene blue instead of trypan blue and the results of experimental staining of various lens materials with different concentrations of the same dye. A "blue dye" was used to enhance visualization during capsulorhexis in a patient undergoing phacoemulsification with implantation of a three-piece silicone lens. Postoperatively, the patient presented with corneal edema and a discolored IOL. Various IOL materials were experimentally stained using methylene blue. Sixteen lenses (4 silicone, 4 hydrophobic acrylic, 4 hydrophilic acrylic, and 4 polymethylmethacrylate) were immersed in 0.5 mL of methylene blue at concentrations of 1%, 0.1%, 0.01%, and 0.001%. These lenses were grossly and microscopically evaluated for discoloration 6 and 24 hours after immersion. The corneal edema resolved within 1 month after the initial surgical procedure. After explantation, gross and microscopic analyses of the explanted silicone lens revealed that its surface and internal substance had been permanently stained blue. In the experimental study, all of the lenses except the polymethylmethacrylate lenses were permanently stained by methylene blue. The hydrophilic acrylic lenses showed the most intense blue staining in all dye concentrations. This is the first clinicopathological report of IOL discoloration due to intraocular use of methylene blue. This and other tissue dyes may be commonly found among surgical supplies in the operating room and due diligence is necessary to avoid mistaking these dyes for those commonly used during ocular surgery.

  7. Human impact on sediment fluxes within the Blue Nile and Atbara River basins

    Science.gov (United States)

    Balthazar, Vincent; Vanacker, Veerle; Girma, Atkilt; Poesen, Jean; Golla, Semunesh

    2013-01-01

    A regional assessment of the spatial variability in sediment yields allows filling the gap between detailed, process-based understanding of erosion at field scale and empirical sediment flux models at global scale. In this paper, we focus on the intrabasin variability in sediment yield within the Blue Nile and Atbara basins as biophysical and anthropogenic factors are presumably acting together to accelerate soil erosion. The Blue Nile and Atbara River systems are characterized by an important spatial variability in sediment fluxes, with area-specific sediment yield (SSY) values ranging between 4 and 4935 t/km2/y. Statistical analyses show that 41% of the observed variation in SSY can be explained by remote sensing proxy data of surface vegetation cover, rainfall intensity, mean annual temperature, and human impact. The comparison of a locally adapted regression model with global predictive sediment flux models indicates that global flux models such as the ART and BQART models are less suited to capture the spatial variability in area-specific sediment yields (SSY), but they are very efficient to predict absolute sediment yields (SY). We developed a modified version of the BQART model that estimates the human influence on sediment yield based on a high resolution composite measure of local human impact (human footprint index) instead of countrywide estimates of GNP/capita. Our modified version of the BQART is able to explain 80% of the observed variation in SY for the Blue Nile and Atbara basins and thereby performs only slightly less than locally adapted regression models.

  8. The analysis and comparison of blue wool fibre populations found at random on clothing.

    Science.gov (United States)

    Wiggins, K; Drummond, P

    2005-01-01

    Fifty-eight garments were taped and searched for mid to dark blue wool fibres. These were then removed from the tapings, mounted on slides and examined using a high-power microscope (400x). A total of 2,740 blue wool fibres were identified and visible range microspectrophotometry (MSP) was performed on them. Three hundred independent blue wool populations were identified on 56 of the 58 garments searched. The lack of control fibres meant the spectral range of each population was unknown. The number of populations may have been underestimated by grouping together the fibres that had broad single peaks and a lack of distinguishing features in the spectra. Although blue wool is considered to be a common fibre type, 300 unique spectral shapes were identified by the use of microspectrophotometry alone. This demonstrates that the dyes used in the dyeing of blue wool are variable. Showing that many different populations of blue wool occur on a range of garments should ensure that the forensic scientist does not underestimate or understate the strength of evidence in cases where blue wool is found. Hopefully this work will enlighten scientists and enable them to also assess the true value of their findings when other commonly occurring fibres are encountered.

  9. Blue-Green Algae

    Science.gov (United States)

    ... that taking a specific blue-green algae product (Super Blue-Green Algae, Cell Tech, Klamath Falls, OR) ... system. Premenstrual syndrome (PMS). Depression. Digestion. Heart disease. Memory. Wound healing. Other conditions. More evidence is needed ...

  10. Blue gods, blue oil, and blue people.

    Science.gov (United States)

    Fairbanks, V F

    1994-09-01

    Studies of the composition of coal tar, which began in Prussia in 1834, profoundly affected the economies of Germany, Great Britain, India, and the rest of the world, as well as medicine and surgery. Such effects include the collapse of the profits of the British indigo monopoly, the growth in economic power of Germany based on coal tar chemistry, and an economic crisis in India that led to more humane tax laws and, ultimately, the independence of India and the end of the British Empire. Additional consequences were the development of antiseptic surgery and the synthesis of a wide variety of useful drugs that have eradicated infections and alleviated pain. Many of these drugs, particularly the commonly used analgesics, sulfonamides, sulfones, and local anesthetics, are derivatives of aniline, originally called "blue oil" or "kyanol." Some of these aniline derivatives, however, have also caused aplastic anemia, agranulocytosis, and methemoglobinemia (that is, "blue people"). Exposure to aniline drugs, particularly when two or three aniline drugs are taken concurrently, seems to be the commonest cause of methemoglobinemia today.

  11. [Acute blue urticaria following subcutaneous injection of patent blue dye].

    Science.gov (United States)

    Hamelin, A; Vial-Dupuy, A; Lebrun-Vignes, B; Francès, C; Soria, A; Barete, S

    2015-11-01

    Patent blue (PB) is a lymphatic vessel dye commonly used in France for sentinel lymph node detection in breast cancer, and less frequently in melanoma, and which may induce hypersensitivity reactions. We report a case of acute blue urticaria occurring within minutes of PB injection. Ten minutes after PB injection for sentinel lymph node detection during breast cancer surgery, a 49-year-old woman developed generalised acute blue urticaria and eyelid angioedema without bronchospasm or haemodynamic disturbance, but requiring discontinuation of surgery. Skin testing using PB and the anaesthetics given were run 6 weeks after the episode and confirmed PB allergy. PB was formally contra-indicated. Immediate hypersensitivity reactions to PB have been reported for between 0.24 and 2.2% of procedures. Such reactions are on occasion severe, chiefly involving anaphylactic shock. Two mechanisms are probably associated: non-specific histamine release and/or an IgE-mediated mechanism. Skin tests are helpful in confirming the diagnosis of PB allergy. Blue acute urticaria is one of the clinical manifestations of immediate hypersensitivity reactions to patent blue dye. Skin tests must be performed 6 weeks after the reaction in order to confirm the diagnosis and formally contra-indicate this substance. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  12. Public Perception of Blue-Algae Bloom Risk in Hongze Lake of China

    Science.gov (United States)

    Huang, Lei; Sun, Kai; Ban, Jie; Bi, Jun

    2010-05-01

    In this work we characterize the public perception of one kind of ecological risk—blue-algae bloom in Hongze Lake, China, based on the psychometric paradigm method. In the first survey of May 2008, 300 respondents of Sihong County adjacent to Hongze Lake were investigated, with a total of 156 questionnaires returned. Then in a second survey of July 2008, 500 respondents from the same research area were investigated, with 318 questionnaires collected. This research firstly attempted to explore the local respondents’ degree of concern regarding ecological changes to Hongze Lake in the last ten years. Secondly, to explore the public perception of blue-algae bloom compared to three typical kinds of hazards including earthquake, nuclear power and public traffic. T-test was used to examine the difference of risk perception in these four hazards over time. The third part of this research, with demographic analysis and nonparametric statistical test, predicted the different groups of respondents’ willingness to accept (WTA) risk of blue-algae bloom in two surveys. Using multiple linear regression analysis, the risk perception model explained 28.3% of variance in the WTA blue-algae bloom risk. The variables of Knowledge, Social effect, Benefit, Controllability and Trust in government were significantly correlated with WTA, which implied that these variables were the main influencing factors explaining the respondents’ willingness to accept risk. The results would help the Chinese government to comprehend the public’s risk perception of the lake ecosystem, inducing well designed communication of risks with public and making effective mitigation policies to improve people’s rational risk judgment.

  13. Jagua blue derived from Genipa americana L. fruit: A natural alternative to commonly used blue food colorants?

    Science.gov (United States)

    Brauch, J E; Zapata-Porras, S P; Buchweitz, M; Aschoff, J K; Carle, R

    2016-11-01

    Due to consumers' increasing health awareness, food industry aims at replacing synthetic dyes by natural counterparts. The substitution of blue synthetic dyes is particularly challenging since current natural alternatives such as phycocyanin (Spirulina) suffer from poor stability. Jagua blue (produced from Genipa americana L. fruit) might represent a potential novel blue pigment source. However, only little is known about its color properties, and application in food systems. Therefore, the blue color and the stability of Jagua blue were assessed for the first time and compared to commonly used colorants, namely, Spirulina, brilliant blue FCF (Blue no. 1), and indigo carmine (Blue no. 2). The reaction rate of Jagua blue was independent of its concentration, confirming thermal degradation to follow first-order kinetics. Between pH 3.6 and 5.0, the color hue of Jagua blue solutions was similar to that of Blue no. 2. However, Jagua blue revealed markedly higher storage stabilities (t 1/2 =86-105days) than Blue no. 2 (t 1 /2 ≤9days) and was less susceptible to acidic pH of 3.6 (t 1 /2 =86days) than Spirulina (t 1 /2 =70days). High negative b* values (blueness) of colored gelatin gels were only obtained for Jagua blue and Spirulina, and the former exhibited higher light stabilities (t 1 /2 =15days) than Spirulina gels (t 1 /2 =4days). Our findings indicate Jagua blue to be a most promising alternative to synthetic dyes, providing relevant information regarding potential food applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Non-invasive in situ Examination of Colour Changes of Blue Paints in Danish Golden Age Paintings

    DEFF Research Database (Denmark)

    Buti, David; Vila, Anna; Filtenborg, Troels Folke

    A non-invasive study of some paintings containing areas of paint with a Prussian blue component has been conducted at the Statens Museum for Kunst. The in situ campaign has been carried out with a range of different spectroscopic portable techniques, provided by the MOLAB transnational access...... of the frame. Prussian blue is a hydrated iron(III) hexacyanoferrate(II) complex of variable composition depending on the manufacturing [1]. It has been reported that the method of preparation, as well as the use of white pigments or extenders to dilute the blue pigment, may be a factor contributing to its......, the current in situ campaign aimed at mapping and understanding the degradation of Prussian blue and lead white admixtures using non-invasive portable techniques. The presence of Prussian blue was detected, with the MOLAB analytical means, in all the exposed, faded areas, although the colour had turned pale...

  15. The Fictional Black Blues Figure: Blues Music and the Art of Narrative Self-Invention

    OpenAIRE

    Mack, Kimberly

    2015-01-01

    The Fictional Black Blues Figure: Blues Music and the Art of Narrative Self-Invention, Kimberly MackMy dissertation examines representations of black American blues musicians in contemporary American fiction, drama, and popular music, and it argues that blues music can be examined as a narrative art rooted in the tradition of fictionalized autobiographical self-fashioning. I contend that the contemporary, multi-racial, literary and musical characters in my project who participate in so-called...

  16. Flickering of the symbiotic variable CH Cygni during outburst

    Energy Technology Data Exchange (ETDEWEB)

    Slovak, M H [Texas Univ., Austin (USA). Dept. of Astronomy; Africano, J

    1978-11-01

    High-speed and conventional BVRI photometry are reported for the bright symbiotic variable CH Cygni (M6 IIIe), obtained during the course of a recent outburst. Unlike the quiescent symbiotic stars, the presence of flickering similar in nature to that seen in the cataclysmic variables has been confirmed during this active phase. The BVRI photometry for a sample of stars in the field is used to derive the reddening and the distance to CH Cyg. A composite energy distribution is derived from 0.35 to 11.0 ..mu..m which clearly establishes the existence of a variable, blue continuum. The lack of variability in the near infrared suggests that the blue continuum arises from a hot companion. A binary model including a subluminous hot companion accreting material from the stellar wind of an SRa variable is discussed to account for the observed photometric properties.

  17. Coomassie Brilliant Blue G is a more potent antagonist of P2 purinergic responses than Reactive Blue 2 (Cibacron Blue 3GA) in rat parotid acinar cells

    International Nuclear Information System (INIS)

    Soltoff, S.P.; McMillian, M.K.; Talamo, B.R.

    1989-01-01

    The ability of Brilliant Blue G (Coomassie Brilliant Blue G) and Reactive Blue 2 (Cibacron Blue 3GA) to block the effects of extracellular ATP on rat parotid acinar cells was examined by evaluating their effects on ATP-stimulated 45Ca 2+ entry and the elevation of [Ca 2+ ]i (Fura 2 fluorescence). ATP (300 microM) increased the rate of Ca 2+ entry to more than 25-times the basal rate and elevated [Ca 2+ ]i to levels more than three times the basal value. Brilliant Blue G and Reactive Blue 2 greatly reduced the entry of 45 Ca 2+ into parotid cells, but the potency of Brilliant Blue G (IC50 approximately 0.4 microM) was about 100-times that of Reactive Blue 2. Fura 2 studies demonstrated that inhibitory concentrations of these compounds did not block the cholinergic response of these cells, thus demonstrating the selectivity of the dye compounds for purinergic receptors. Unlike Reactive Blue 2, effective concentrations of Brilliant Blue G did not substantially quench Fura 2 fluorescence. The greater potency of Brilliant Blue G suggests that it may be very useful in identifying P2-type purinergic receptors, especially in studies which utilize fluorescent probes

  18. Measuring Blue Space Visibility and 'Blue Recreation' in the Everyday Lives of Children in a Capital City.

    Science.gov (United States)

    Pearson, Amber L; Bottomley, Ross; Chambers, Tim; Thornton, Lukar; Stanley, James; Smith, Moira; Barr, Michelle; Signal, Louise

    2017-05-26

    Blue spaces (water bodies) may promote positive mental and physical health through opportunities for relaxation, recreation, and social connections. However, we know little about the nature and extent of everyday exposure to blue spaces, particularly in settings outside the home or among children, nor whether exposure varies by individual or household characteristics. Wearable cameras offer a novel, reliable method for blue space exposure measurement. In this study, we used images from cameras worn over two days by 166 children in Wellington, New Zealand, and conducted content and blue space quantification analysis on each image ( n = 749,389). Blue space was identified in 24,721 images (3.6%), with a total of 23 blue recreation events. Visual exposure and participation in blue recreation did not differ by ethnicity, weight status, household deprivation, or residential proximity to the coastline. Significant differences in both visual exposure to blue space and participation in blue recreation were observed, whereby children from the most deprived schools had significantly higher rates of blue space exposure than children from low deprivation schools. Schools may be important settings to promote equitable blue space exposures. Childhood exposures to blue space may not follow the expected income inequality trends observed among adults.

  19. The effect of inter-annual variability of consumption, production, trade and climate on crop-related green and blue water footprints and inter-regional virtual water trade: A study for China (1978-2008).

    Science.gov (United States)

    Zhuo, La; Mekonnen, Mesfin M; Hoekstra, Arjen Y

    2016-05-01

    Previous studies into the relation between human consumption and indirect water resources use have unveiled the remote connections in virtual water (VW) trade networks, which show how communities externalize their water footprint (WF) to places far beyond their own region, but little has been done to understand variability in time. This study quantifies the effect of inter-annual variability of consumption, production, trade and climate on WF and VW trade, using China over the period 1978-2008 as a case study. Evapotranspiration, crop yields and green and blue WFs of crops are estimated at a 5 × 5 arc-minute resolution for 22 crops, for each year in the study period, thus accounting for climate variability. The results show that crop yield improvements during the study period helped to reduce the national average WF of crop consumption per capita by 23%, with a decreasing contribution to the total from cereals and increasing contribution from oil crops. The total consumptive WFs of national crop consumption and crop production, however, grew by 6% and 7%, respectively. By 2008, 28% of total water consumption in crop fields in China served the production of crops for export to other regions and, on average, 35% of the crop-related WF of a Chinese consumer was outside its own province. Historically, the net VW within China was from the water-rich South to the water-scarce North, but intensifying North-to-South crop trade reversed the net VW flow since 2000, which amounted 6% of North's WF of crop production in 2008. South China thus gradually became dependent on food supply from the water-scarce North. Besides, during the whole study period, China's domestic inter-regional VW flows went dominantly from areas with a relatively large to areas with a relatively small blue WF per unit of crop, which in 2008 resulted in a trade-related blue water loss of 7% of the national total blue WF of crop production. The case of China shows that domestic trade, as governed by

  20. 75 FR 65525 - Anthem Blue Cross Blue Shield, Claim Management Services, Inc. Operations, a Division of...

    Science.gov (United States)

    2010-10-25

    ... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-74,327] Anthem Blue Cross Blue Shield, Claim Management Services, Inc. Operations, a Division of Wellpoint, Inc., Green Bay, WI; Notice... former workers of Anthem Blue Cross Blue Shield, Claim Management Services, Inc. Operations, a Division...

  1. Dyes adsorption blue vegetable and blue watercolor by natural zeolites modified with surfactants

    International Nuclear Information System (INIS)

    Jardon S, C. C.; Olguin G, M. T.; Diaz N, M. C.

    2009-01-01

    In this work was carried out the dyes removal blue vegetable and blue watercolor of aqueous solutions, to 20 C, at different times and using a zeolite mineral of Parral (Chihuahua, Mexico) modified with hexadecyl trimethyl ammonium bromide or dodecyl trimethyl ammonium bromide. The zeolite was characterized before and after of its adaptation with NaCl and later with HDTMABr and DTMABr. For the materials characterization were used the scanning electron microscopy of high vacuum; elementary microanalysis by X-ray spectroscopy of dispersed energy and X-ray diffraction techniques. It was found that the surfactant type absorbed in the zeolite material influences on the adsorption process of the blue dye. Likewise, the chemical structure between the vegetable blue dye and the blue watercolor, determines the efficiency of the color removal of the water, by the zeolites modified with the surfactants. (Author)

  2. EXTraS: Exploring the X-ray Transient and variable Sky

    Science.gov (United States)

    De Luca, A.; Salvaterra, R.; Tiengo, A.; D'Agostino, D.; Watson, M.; Haberl, F.; Wilms, J.

    2017-10-01

    The EXTraS project extracted all temporal domain information buried in the whole database collected by the EPIC cameras onboard the XMM-Newton mission. This included a search and characterisation of variability, both periodic and aperiodic, in hundreds of thousands of sources spanning more than eight orders of magnitude in time scale and six orders of magnitude in flux, as well as a search for fast transients, missed by standard image analysis. Phenomenological classification of variable sources, based on X-ray and multiwavelength information, has also been performed. All results and products of EXTraS are made available to the scientific community through a web public data archive. A dedicated science gateway will allow scientists to apply EXTraS pipelines on new observations. EXTraS is the most comprehensive analysis of variability, on the largest ever sample of soft X-ray sources. The resulting archive and tools disclose an enormous scientific discovery space to the community, with applications ranging from the search for rare events to population studies, with impact on the study of virtually all astrophysical source classes. EXTraS, funded within the EU/FP7 framework, is carried out by a collaboration including INAF (Italy), IUSS (Italy), CNR/IMATI (Italy), University of Leicester (UK), MPE (Germany) and ECAP (Germany).

  3. The intermediate-age pre-cataclysmic variables SDSS J172406+562003 and RE J2013+4002

    Science.gov (United States)

    Shimansky, V. V.; Borisov, N. V.; Nurtdinova, D. N.; Mitrofanova, A. A.; Vlasyuk, V. V.; Spiridonova, O. I.

    2012-06-01

    We have analyzed the physical status of the pre-cataclysmic variables SDSSJ172406+562003 and RE J2013+4002, which have evolved after their common-envelope stage a time t = 106-107 years. Spectroscopy and photometry of these systems were performed with the 6-m and 1-m telescopes of the Special Astrophysical Observatory. We demonstrate that emission lines in the spectra were formed solely by the reflection of radiation emitted by the white dwarfs on the surfaces of their cool companions, under conditions close to local thermodynamic equilibrium. These effects are also responsible for most of the objects' photometric variability amplitude. However, comparing the light curves of SDSS 172406 from different epochs, we find aperiodic brightness variations, probably due to spottedness of the surface of the secondary. Jointly analyzing the spectra, radial-velocity curves, and light curves of the pre-cataclysmic variables and modeling the reflection effects, we have derived their fundamental parameters. We demonstrate that the secondaries in these systems are consistent with evolutionary models for main-sequence stars and do not have the luminosity excesses characteristic of cool stars in young pre-cataclysmic variables.

  4. Blue Whale (Balaenoptera musculus Behavior and Group Dynamics as Observed from an Aircraft off Southern California

    Directory of Open Access Journals (Sweden)

    Kate Lomac-MacNair

    2016-02-01

    Full Text Available Group behavior and interactions of endangered blue whales (Balaenoptera musculus have not been systematically studied. Such behavioral data are often overlooked when assessing anthropogenic effects. Yet behavioral data are necessary to compare “normal” behaviors with behavior affected by anthropogenic factors of concern relative to effective management and recovery of blue whales. For a baseline study, we hypothesized that the response variables sighting rate, group size, calf presence and group cohesion (i.e., spacing between individuals within a group differed according to the spatio-temporal explanatory variables behavioral state, time of day, season, water depth and distance from shore. To address our hypotheses, we flew systematic line transect surveys in southern California and collected focal group data. Two sets of data were separately analyzed using different sampling approaches: (1 point sample data associated with the first sighting of a blue whale(s, and (2 extended all-occurrence focal group behavioral sampling data (i.e., focal follows collected on a subsample of all sightings while the aircraft circled at a radial distance of approximately 0.5-1 km and an altitude of 1,500 m for extended periods of 5 – 60 minutes. Chi-square contingency table and G² analyses were used to assess statistical relationships between response and explanatory variables. We conducted 18 one-week-long aerial surveys spanning October 2008 through May 2013 (at least once during every month except December, totaling 87,555 km of observation effort. Seventy blue whale sightings (117 individuals were seen, ranging in size from 1 – 6 whales, and focal follow was performed on over half (55% of these sightings. Results supported our hypotheses that blue whale group characteristics were related to behavioral state and spatio-temporal variables. Sighting rates were significantly highest during summer followed by spring, fall, and winter. Group type differed

  5. Blue Ocean Thinking

    Science.gov (United States)

    Orem, Donna

    2016-01-01

    This article describes a concept called the "blue ocean thinking strategy," developed by W. Chan Kim and Renée Mauborgne, professors at INSEAD, an international graduate school of business in France. The "blue ocean" thinking strategy considers opportunities to create new markets for services, rather than focusing solely on…

  6. Blue Emission in Proteins

    OpenAIRE

    Sarkar, Sohini; Sengupta, Abhigyan; Hazra, Partha; Mandal, Pankaj

    2014-01-01

    Recent literatures reported blue-green emission from amyloid fibril as exclusive signature of fibril formation. This unusual visible luminescence is regularly used to monitor fibril growth. Blue-green emission has also been observed in crystalline protein and in solution. However, the origin of this emission is not known exactly. Our spectroscopic study of serum proteins reveals that the blue-green emission is a property of protein monomer. Evidences suggest that semiconductor-like band struc...

  7. Thematic Mapper Analysis of Blue Oak (Quercus douglasii) in Central California

    Science.gov (United States)

    Paul A. Lefebvre Jr.; Frank W. Davis; Mark Borchert

    1991-01-01

    Digital Thematic Mapper (TM) satellite data from September 1986 and December 1985 were analyzed to determine seasonal reflectance properties of blue oak rangeland in the La Panza mountains of San Luis Obispo County. Linear regression analysis was conducted to examine relationships between TM reflectance and oak canopy cover, basal area, and site topographic variables....

  8. Cataclysmic variables, Hubble-Sandage variables and eta Carinae

    International Nuclear Information System (INIS)

    Bath, G.T.

    1980-01-01

    The Hubble-Sandage variables are the most luminous stars in external galaxies. They were first investigated by Hubble and Sandage (1953) for use as distance indicators. Their main characteristics are high luminosity, blue colour indices, and irregular variability. Spectroscopically they show hydrogen and helium in emission with occasionally weaker FeII and [FeII], and no Balmer jump (Humphreys 1975, 1978). In this respect they closely resemble cataclysmic variables, particularly dwarf novae. In the quiescent state dwarf novae show broad H and HeI, together with a strong UV continuum. In contrast to the spectroscopic similarities, the luminosities could hardly differ more. Rather than being the brightest stars known, quiescent dwarf novae are as faint or fainter than the sun. It is suggested that the close correspondence between the spectral appearance of the two classes combined with the difference in luminosity is well accounted for by a model of Hubble-Sandage variables in which the same physical processes are occurring, but on a larger scale. (Auth.)

  9. Evaluation of Code Blue Implementation Outcomes

    Directory of Open Access Journals (Sweden)

    Bengü Özütürk

    2015-09-01

    Full Text Available Aim: In this study, we aimed to emphasize the importance of Code Blue implementation and to determine deficiencies in this regard. Methods: After obtaining the ethics committee approval, 225 patient’s code blue call data between 2012 and 2014 January were retrospectively analyzed. Age and gender of the patients, date and time of the call and the clinics giving Code Blue, the time needed for the Code Blue team to arrive, the rates of false Code Blue calls, reasons for Code Blue calls and patient outcomes were investigated. Results: A total of 225 patients (149 male, 76 female were evaluated in the study. The mean age of the patients was 54.1 years. 142 (67.2% Code Blue calls occurred after hours and by emergency unit. The mean time for the Code Blue team to arrive was 1.10 minutes. Spontaneous circulation was provided in 137 patients (60.8%; 88 (39.1% died. The most commonly identified possible causes were of cardiac origin. Conclusion: This study showed that Code Blue implementation with a professional team within an efficient and targeted time increase the survival rate. Therefore, we conclude that the application of Code Blue carried out by a trained team is an essential standard in hospitals. (The Medical Bulletin of Haseki 2015; 53:204-8

  10. Competition model for aperiodic stochastic resonance in a Fitzhugh-Nagumo model of cardiac sensory neurons.

    Science.gov (United States)

    Kember, G C; Fenton, G A; Armour, J A; Kalyaniwalla, N

    2001-04-01

    Regional cardiac control depends upon feedback of the status of the heart from afferent neurons responding to chemical and mechanical stimuli as transduced by an array of sensory neurites. Emerging experimental evidence shows that neural control in the heart may be partially exerted using subthreshold inputs that are amplified by noisy mechanical fluctuations. This amplification is known as aperiodic stochastic resonance (ASR). Neural control in the noisy, subthreshold regime is difficult to see since there is a near absence of any correlation between input and the output, the latter being the average firing (spiking) rate of the neuron. This lack of correlation is unresolved by traditional energy models of ASR since these models are unsuitable for identifying "cause and effect" between such inputs and outputs. In this paper, the "competition between averages" model is used to determine what portion of a noisy, subthreshold input is responsible, on average, for the output of sensory neurons as represented by the Fitzhugh-Nagumo equations. A physiologically relevant conclusion of this analysis is that a nearly constant amount of input is responsible for a spike, on average, and this amount is approximately independent of the firing rate. Hence, correlation measures are generally reduced as the firing rate is lowered even though neural control under this model is actually unaffected.

  11. Blue objects in the field of M31

    Energy Technology Data Exchange (ETDEWEB)

    Romano, G [Padua Univ. (Italy). Istituto di Astronomia

    1976-10-01

    This paper gives the results of a photometric study of star-like blue objects Nos. 14, 15, 16, 17, and 18 discovered by Boerngen et al. (1970) in the field of M31 and of the QSO OA 33. Three of these objects - Nos. 14, 16 and 17 - exhibit variable light. No. 14 is a probable U Geminorum-star; No. 16 is a QSO and very likely also the No. 17. Finally, a candidate is suggested for the optical counterpart of OA 33.

  12. PRECISION PHOTOMETRIC MONITORING OF VERY LOW MASS σ ORIONIS CLUSTER MEMBERS: VARIABILITY AND ROTATION AT A FEW Myr

    International Nuclear Information System (INIS)

    Cody, Ann Marie; Hillenbrand, Lynne A.

    2010-01-01

    We present high-precision photometry on 107 variable low-mass stars and brown dwarfs in the ∼3 Myr σ Orionis open cluster. We have carried out I-band photometric monitoring within two fields, encompassing 153 confirmed or candidate members of the low-mass cluster population, from 0.02 to 0.5 M sun . We are sensitive to brightness changes on timescales from 10 minutes to two weeks with amplitudes as low as 0.004 mag, and find variability on these timescales in nearly 70% of cluster members. We identify both periodic and aperiodic modes of variability, as well as semi-periodic rapid fading events that are not accounted for by the standard explanations of rotational modulation of surface features or accretion. We have incorporated both optical and infrared color data to uncover trends in variability with mass and circumstellar disks. While the data confirm that the lowest-mass objects (M sun ) rotate more rapidly than the 0.2-0.5 M sun members, they do not support a direct connection between rotation rate and the presence of a disk. Finally, we speculate on the origin of irregular variability in cluster members with no evidence for disks or accretion.

  13. The WFCAM multiwavelength Variable Star Catalog

    Science.gov (United States)

    Ferreira Lopes, C. E.; Dékány, I.; Catelan, M.; Cross, N. J. G.; Angeloni, R.; Leão, I. C.; De Medeiros, J. R.

    2015-01-01

    Context. Stellar variability in the near-infrared (NIR) remains largely unexplored. The exploitation of public science archives with data-mining methods offers a perspective for a time-domain exploration of the NIR sky. Aims: We perform a comprehensive search for stellar variability using the optical-NIR multiband photometric data in the public Calibration Database of the WFCAM Science Archive (WSA), with the aim of contributing to the general census of variable stars and of extending the current scarce inventory of accurate NIR light curves for a number of variable star classes. Methods: Standard data-mining methods were applied to extract and fine-tune time-series data from the WSA. We introduced new variability indices designed for multiband data with correlated sampling, and applied them for preselecting variable star candidates, i.e., light curves that are dominated by correlated variations, from noise-dominated ones. Preselection criteria were established by robust numerical tests for evaluating the response of variability indices to the colored noise characteristic of the data. We performed a period search using the string-length minimization method on an initial catalog of 6551 variable star candidates preselected by variability indices. Further frequency analysis was performed on positive candidates using three additional methods in combination, in order to cope with aliasing. Results: We find 275 periodic variable stars and an additional 44 objects with suspected variability with uncertain periods or apparently aperiodic variation. Only 44 of these objects had been previously known, including 11 RR Lyrae stars on the outskirts of the globular cluster M 3 (NGC 5272). We provide a preliminary classification of the new variable stars that have well-measured light curves, but the variability types of a large number of objects remain ambiguous. We classify most of the new variables as contact binary stars, but we also find several pulsating stars, among which

  14. Different stimulation frequencies alter synchronous fluctuations in motor evoked potential amplitude of intrinsic hand muscles – a TMS study.

    Directory of Open Access Journals (Sweden)

    Martin Victor Sale

    2016-03-01

    Full Text Available The amplitude of motor-evoked potentials (MEPs elicited with transcranial magnetic stimulation (TMS varies from trial-to-trial. Synchronous oscillations in cortical neuronal excitability contribute to this variability, however it is not known how different frequencies of stimulation influence MEP variability, and whether these oscillations are rhythmic or aperiodic. We stimulated the motor cortex with TMS at different regular (i.e., rhythmic rates, and compared this with pseudo-random (aperiodic timing. In 18 subjects, TMS was applied at three regular frequencies (0.05 Hz, 0.2 Hz, 1 Hz and one aperiodic frequency (mean 0.2 Hz. MEPs (n = 50 were recorded from three intrinsic hand muscles of the left hand with different functional and anatomical relations. MEP amplitude correlation was highest for the functionally related muscle pair, less for the anatomically related muscle pair and least for the functionally- and anatomically-unrelated muscle pair. MEP correlations were greatest with 1 Hz, and least for stimulation at 0.05 Hz. Corticospinal neuron synchrony is higher with shorter TMS intervals. Further, corticospinal neuron synchrony is similar irrespective of whether the stimulation is periodic or aperiodic. These findings suggest TMS frequency is a crucial consideration for studies using TMS to probe correlated activity between muscle pairs.

  15. Different Stimulation Frequencies Alter Synchronous Fluctuations in Motor Evoked Potential Amplitude of Intrinsic Hand Muscles—a TMS Study

    Science.gov (United States)

    Sale, Martin V.; Rogasch, Nigel C.; Nordstrom, Michael A.

    2016-01-01

    The amplitude of motor-evoked potentials (MEPs) elicited with transcranial magnetic stimulation (TMS) varies from trial-to-trial. Synchronous oscillations in cortical neuronal excitability contribute to this variability, however it is not known how different frequencies of stimulation influence MEP variability, and whether these oscillations are rhythmic or aperiodic. We stimulated the motor cortex with TMS at different regular (i.e., rhythmic) rates, and compared this with pseudo-random (aperiodic) timing. In 18 subjects, TMS was applied at three regular frequencies (0.05 Hz, 0.2 Hz, 1 Hz) and one aperiodic frequency (mean 0.2 Hz). MEPs (n = 50) were recorded from three intrinsic hand muscles of the left hand with different functional and anatomical relations. MEP amplitude correlation was highest for the functionally related muscle pair, less for the anatomically related muscle pair and least for the functionally- and anatomically-unrelated muscle pair. MEP correlations were greatest with 1 Hz, and least for stimulation at 0.05 Hz. Corticospinal neuron synchrony is higher with shorter TMS intervals. Further, corticospinal neuron synchrony is similar irrespective of whether the stimulation is periodic or aperiodic. These findings suggest TMS frequency is a crucial consideration for studies using TMS to probe correlated activity between muscle pairs. PMID:27014031

  16. A resolution to the blue whiting (Micromesistius poutassou population paradox?

    Directory of Open Access Journals (Sweden)

    Fabien Pointin

    Full Text Available We provide the strongest evidence to date supporting the existence of two independent blue whiting (Micromesistius poutassou (Risso, 1827 populations in the North Atlantic. In spite of extensive data collected in conjunction with the fishery, the population structure of blue whiting is poorly understood. On one hand, genetic, morphometric, otolith and drift modelling studies point towards the existence of two populations, but, on the other hand, observations of adult distributions point towards a single population. A paradox therefore arises in attempting to reconcile these two sets of information. Here we analyse 1100 observations of blue whiting larvae from the Continuous Plankton Recorder (CPR from 1948-2005 using modern statistical techniques. We show a clear spatial separation between a northern spawning area, in the Rockall Trough, and a southern one, off the Porcupine Seabight. We further show a difference in the timing of spawning between these sites of at least a month, and meaningful differences in interannual variability. The results therefore support the two-population hypothesis. Furthermore, we resolve the paradox by showing that the acoustic observations cited in support of the single-population model are not capable of resolving both populations, as they occur too late in the year and do not extend sufficiently far south to cover the southern population: the confusion is the result of a simple observational artefact. We conclude that blue whiting in the North Atlantic comprises two populations.

  17. Direct sequencing of mitochondrial DNA detects highly divergent haplotypes in blue marlin (Makaira nigricans).

    Science.gov (United States)

    Finnerty, J R; Block, B A

    1992-06-01

    We were able to differentiate between species of billfish (Istiophoridae family) and to detect considerable intraspecific variation in the blue marlin (Makaira nigricans) by directly sequencing a polymerase chain reaction (PCR)-amplified, 612-bp fragment of the mitochondrial cytochrome b gene. Thirteen variable nucleotide sites separated blue marlin (n = 26) into 7 genotypes. On average, these genotypes differed by 5.7 base substitutions. A smaller sample of swordfish from an equally broad geographic distribution displayed relatively little intraspecific variation, with an average of 1.3 substitutions separating different genotypes. A cladistic analysis of blue marlin cytochrome b variants indicates two major divergent evolutionary lines within the species. The frequencies of these two major evolutionary lines differ significantly between Atlantic and Pacific ocean basins. This finding is important given that the Atlantic stocks of blue marlin are considered endangered. Migration from the Pacific can help replenish the numbers of blue marlin in the Atlantic, but the loss of certain mitochondrial DNA haplotypes in the Atlantic due to overfishing probably could not be remedied by an influx of Pacific fish because of their absence in the Pacific population. Fishery management strategies should attempt to preserve the genetic diversity within the species. The detection of DNA sequence polymorphism indicates the utility of PCR technology in pelagic fishery genetics.

  18. A MODEL FOR (QUASI-)PERIODIC MULTIWAVELENGTH PHOTOMETRIC VARIABILITY IN YOUNG STELLAR OBJECTS

    Energy Technology Data Exchange (ETDEWEB)

    Kesseli, Aurora Y. [Boston University, 725 Commonwealth Ave, Boston, MA 02215 (United States); Petkova, Maya A.; Wood, Kenneth; Gregory, Scott G. [SUPA, School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews, Fife, KY16 9AD (United Kingdom); Whitney, Barbara A. [Department of Astronomy, University of Wisconsin-Madison, 475 N. Charter St, Madison, WI 53706 (United States); Hillenbrand, L. A. [Astronomy Department, California Institute of Technology, Pasadena, CA 91125 (United States); Stauffer, J. R.; Morales-Calderon, M.; Rebull, L. [Spitzer Science Center, California Institute of Technology, CA 91125 (United States); Alencar, S. H. P., E-mail: aurorak@bu.com [Departamento de Física—ICEx—UFMG, Av. Antônio Carlos, 6627, 30270-901, Belo Horizonte, MG (Brazil)

    2016-09-01

    We present radiation transfer models of rotating young stellar objects (YSOs) with hot spots in their atmospheres, inner disk warps, and other three-dimensional effects in the nearby circumstellar environment. Our models are based on the geometry expected from magneto-accretion theory, where material moving inward in the disk flows along magnetic field lines to the star and creates stellar hot spots upon impact. Due to rotation of the star and magnetosphere, the disk is variably illuminated. We compare our model light curves to data from the Spitzer YSOVAR project to determine if these processes can explain the variability observed at optical and mid-infrared wavelengths in young stars. We focus on those variables exhibiting “dipper” behavior that may be periodic, quasi-periodic, or aperiodic. We find that the stellar hot-spot size and temperature affects the optical and near-infrared light curves, while the shape and vertical extent of the inner disk warp affects the mid-IR light curve variations. Clumpy disk distributions with non-uniform fractal density structure produce more stochastic light curves. We conclude that magneto-accretion theory is consistent with certain aspects of the multiwavelength photometric variability exhibited by low-mass YSOs. More detailed modeling of individual sources can be used to better determine the stellar hot-spot and inner disk geometries of particular sources.

  19. "Blue-Collar Blues" uurib töösuhteid uutes oludes / Janar Ala

    Index Scriptorium Estoniae

    Ala, Janar, 1979-

    2009-01-01

    Tööproblemaatikat käsitlev näitus "Blue-Collar Blues" Tallinna Kunstihoones ja Tallinna Kunstihoone galeriis 31. jaanuarini 2010, kuraator Anders Härm. Lähemalt belgia-mehhiko kunstniku Francis Alys'e videost, austria kunstniku Oliver Ressleri ning venetsueela-saksa politoloogi Dario Azzelini videost "Viis tehast. Tööliste kontroll Venezuelas"

  20. The spectrum of dermatoscopic patterns in blue nevi.

    Science.gov (United States)

    Di Cesare, Antonella; Sera, Francesco; Gulia, Andrea; Coletti, Gino; Micantonio, Tamara; Fargnoli, Maria Concetta; Peris, Ketty

    2012-08-01

    Blue nevi are congenital or acquired, dermal dendritic melanocytic proliferations that can simulate melanocytic and nonmelanocytic lesions including melanoma, cutaneous metastasis of melanoma, Spitz/Reed nevi, and basal cell carcinoma. We sought to investigate global and local dermatoscopic patterns of blue nevi compared with melanomas and basal cell carcinomas. We retrospectively analyzed global and local features in 95 dermatoscopic images of blue nevi and in 190 melanomas and basal cell carcinomas that were selected as control lesions on the basis of similar pigmentation. Lesion pigmentation was classified as monochromatic, dichromatic, or multichromatic. A global pattern characterized by homogeneous pigmentation was observed in all of 95 (100%) blue nevi. Eighty of 95 (84.2%) blue nevi presented a homogeneous pattern consisting of one color (blue, black, or brown) or two colors (blue-brown, blue-gray, or blue-black). Fifteen of 95 (15.8%) blue nevi had a multichromatic (blue, gray, black, brown, and/or red) pigmentation. In all, 47 of 95 (49.5%) blue nevi were characterized by pigmentation in the absence of pigment network or any other local dermatoscopic features. And 48 of 95 (50.5%) blue nevi showed local dermatoscopic patterns including whitish scarlike depigmentation, dots/globules, vascular pattern, streaks, and networklike pattern. The study was retrospective and involved only Caucasian people of Italian origin. The characteristic feature of blue nevi is a homogeneous pigmentation that is blue, blue-gray, blue-brown, or blue-black. We showed that a wide spectrum of local dermatoscopic features (whitish scarlike depigmentation, dots/globules, peripheral streaks or vessels) may also be present. In such cases, clinical and dermatoscopic distinction from melanoma or nonmelanocytic lesions may be difficult or impossible, and surgical excision is necessary. Copyright © 2011 American Academy of Dermatology, Inc. Published by Mosby, Inc. All rights reserved.

  1. The Blue Coma: The Role of Methylene Blue in Unexplained Coma After Cardiac Surgery.

    Science.gov (United States)

    Martino, Enrico Antonio; Winterton, Dario; Nardelli, Pasquale; Pasin, Laura; Calabrò, Maria Grazia; Bove, Tiziana; Fanelli, Giovanna; Zangrillo, Alberto; Landoni, Giovanni

    2016-04-01

    Methylene blue commonly is used as a dye or an antidote, but also can be used off label as a vasopressor. Serotonin toxicity is a potentially lethal and often misdiagnosed condition that can result from drug interaction. Mild serotonin toxicity previously was reported in settings in which methylene blue was used as a dye. The authors report 3 cases of life-threatening serotonin toxicity in patients undergoing chronic selective serotonin reuptake inhibitor (SSRI) therapy who also underwent cardiac surgery and received methylene blue to treat vasoplegic syndrome. An observational study. A cardiothoracic intensive care unit (ICU) in a teaching hospital. Three patients who received methylene blue after cardiac surgery, later discovered to be undergoing chronic SSRI therapy. None. All 3 patients received high doses of fentanyl during general anesthesia. They all developed vasoplegic syndrome and consequently were given methylene blue in the ICU. All 3 patients developed serotonin toxicity, including coma, after this administration and diagnostic tests were negative for acute intracranial pathology. Coma lasted between 1 and 5 days. Two patients were discharged from the ICU shortly after awakening, whereas the third patient experienced a complicated postoperative course for concomitant refractory low-cardiac-output syndrome. Patients undergoing chronic SSRI therapy should not be administered methylene blue to treat vasoplegic syndrome. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Plasma volume methodology: Evans blue, hemoglobin-hematocrit, and mass density transformations

    Science.gov (United States)

    Greenleaf, J. E.; Hinghofer-Szalkay, H.

    1985-01-01

    Methods for measuring absolute levels and changes in plasma volume are presented along with derivations of pertinent equations. Reduction in variability of the Evans blue dye dilution technique using chromatographic column purification suggests that the day-to-day variability in the plasma volume in humans is less than + or - 20 m1. Mass density determination using the mechanical-oscillator technique provides a method for measuring vascular fluid shifts continuously for assessing the density of the filtrate, and for quantifying movements of protein across microvascular walls. Equations for the calculation of volume and density of shifted fluid are presented.

  3. Identification of Young Stellar Variables with KELT for K2 . I. Taurus Dippers and Rotators

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, Joseph E.; Cargile, Phillip A. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Ansdell, Megan [Institute for Astronomy, University of Hawaií at Manoa, Honolulu, HI 96822 (United States); Oelkers, Ryan J.; Somers, Garrett; Lund, Michael B.; Stassun, Keivan G. [Department of Physics and Astronomy, Vanderbilt University, 6301 Stevenson Center, Nashville, TN 37235 (United States); Gaidos, Eric [Department of Geology and Geophysics, University of Hawaií at Manoa, Honolulu, HI 96822 (United States); Cody, Ann Marie [NASA Ames Research Center, Mountain View, CA 94035 (United States); Stevens, Daniel J.; Gaudi, B. Scott [Department of Astronomy, The Ohio State University, Columbus, OH 43210 (United States); James, David [Astronomy Department, University of Washington, Box 351580, Seattle, WA 98195 (United States); Beatty, Thomas G. [Department of Astronomy and Astrophysics, The Pennsylvania State University, 525 Davey Lab, University Park, PA 16802 (United States); Siverd, Robert J. [Las Cumbres Observatory Global Telescope Network, 6740 Cortona Drive, Suite 102, Santa Barbara, CA 93117 (United States); Kuhn, Rudolf B. [South African Astronomical Observatory, PO Box 9, Observatory 7935 (South Africa); Pepper, Joshua [Department of Physics, Lehigh University, 16 Memorial Drive East, Bethlehem, PA 18015 (United States)

    2017-10-20

    One of the most well-studied young stellar associations, Taurus–Auriga, was observed by the extended Kepler mission, K2 , in the spring of 2017. K2 Campaign 13 (C13) is a unique opportunity to study many stars in this young association at high photometric precision and cadence. Using observations from the Kilodegree Extremely Little Telescope (KELT) survey, we identify “dippers,” aperiodic and periodic variables among K2 C13 target stars. This release of the KELT data (light curve data in e-tables) provides the community with long-time baseline observations to assist in the understanding of the more exotic variables in the association. Transient-like phenomena on timescales of months to years are known characteristics in the light curves of young stellar objects, making contextual pre- and post- K2 observations critical to understanding their underlying processes. We are providing a comprehensive set of the KELT light curves for known Taurus–Auriga stars in K2 C13. The combined data sets from K2 and KELT should permit a broad array of investigations related to star formation, stellar variability, and protoplanetary environments.

  4. Identification of Young Stellar Variables with KELT for K2 . I. Taurus Dippers and Rotators

    International Nuclear Information System (INIS)

    Rodriguez, Joseph E.; Cargile, Phillip A.; Ansdell, Megan; Oelkers, Ryan J.; Somers, Garrett; Lund, Michael B.; Stassun, Keivan G.; Gaidos, Eric; Cody, Ann Marie; Stevens, Daniel J.; Gaudi, B. Scott; James, David; Beatty, Thomas G.; Siverd, Robert J.; Kuhn, Rudolf B.; Pepper, Joshua

    2017-01-01

    One of the most well-studied young stellar associations, Taurus–Auriga, was observed by the extended Kepler mission, K2 , in the spring of 2017. K2 Campaign 13 (C13) is a unique opportunity to study many stars in this young association at high photometric precision and cadence. Using observations from the Kilodegree Extremely Little Telescope (KELT) survey, we identify “dippers,” aperiodic and periodic variables among K2 C13 target stars. This release of the KELT data (light curve data in e-tables) provides the community with long-time baseline observations to assist in the understanding of the more exotic variables in the association. Transient-like phenomena on timescales of months to years are known characteristics in the light curves of young stellar objects, making contextual pre- and post- K2 observations critical to understanding their underlying processes. We are providing a comprehensive set of the KELT light curves for known Taurus–Auriga stars in K2 C13. The combined data sets from K2 and KELT should permit a broad array of investigations related to star formation, stellar variability, and protoplanetary environments.

  5. Quantum discord and classical correlation signatures of mobility edges in one-dimensional aperiodic single-electron systems

    International Nuclear Information System (INIS)

    Gong, Longyan; Zhu, Hao; Zhao, Shengmei; Cheng, Weiwen; Sheng, Yubo

    2012-01-01

    We investigate numerically the quantum discord and the classical correlation in a one-dimensional slowly varying potential model and a one-dimensional Soukoulis–Economou ones, respectively. There are well-defined mobility edges in the slowly varying potential model, while there are discrepancies on mobility edges in the Soukoulis–Economou ones. In the slowly varying potential model, we find that extended and localized states can be distinguished by both the quantum discord and the classical correlation. There are sharp transitions in the quantum discord and the classical correlation at mobility edges. Based on these, we study “mobility edges” in the Soukoulis–Economou model using the quantum discord and the classical correlation, which gives another perspectives for these “mobility edges”. All these provide us good quantities, i.e., the quantum discord and the classical correlation, to reflect mobility edges in these one-dimensional aperiodic single-electron systems. Moreover, our studies propose a consistent interpretation of the discrepancies between previous numerical results about the Soukoulis–Economou model. -- Highlights: ► Quantum discord and classical correlation can signal mobility edges in two models. ► An interpretation for mobility edges in the Soukoulis–Economou model is proposed. ► Quantum discord and classical correlation can reflect well localization properties.

  6. Why Blue-Collar Blacks Help Less

    OpenAIRE

    Smith, Sandra Susan; Young, Kara Alexis

    2013-01-01

    Why are blue-collar blacks less likely to help jobseekers than jobholders from other ethnoracial groups or even than more affluent blacks? Drawing from in-depth, semi-structured interviews with 97 black and Latino workers at one large, public sector employer, we find that blue-collar black workers both helped less proactively and rejected more requests for assistance than did blue-collar Latino and white-collar black workers. We attribute blue-collar blacks’ more passive engagement to their...

  7. Phase Transition between Black and Blue Phosphorenes: A Quantum Monte Carlo Study

    Science.gov (United States)

    Li, Lesheng; Yao, Yi; Reeves, Kyle; Kanai, Yosuke

    Phase transition of the more common black phosphorene to blue phosphorene is of great interest because they are predicted to exhibit unique electronic and optical properties. However, these two phases are predicted to be separated by a rather large energy barrier. In this work, we study the transition pathway between black and blue phosphorenes by using the variable cell nudge elastic band method combined with density functional theory calculation. We show how diffusion quantum Monte Carlo method can be used for determining the energetics of the phase transition and demonstrate the use of two approaches for removing finite-size errors. Finally, we predict how applied stress can be used to control the energetic balance between these two different phases of phosphorene.

  8. ENERGY-DEPENDENT POWER SPECTRAL STATES AND ORIGIN OF APERIODIC VARIABILITY IN BLACK HOLE BINARIES

    International Nuclear Information System (INIS)

    Yu Wenfei; Zhang Wenda

    2013-01-01

    We found that the black hole candidate MAXI J1659–152 showed distinct power spectra, i.e., power-law noise (PLN) versus band-limited noise (BLN) plus quasi-periodic oscillations (QPOs) below and above about 2 keV, respectively, in observations with Swift and the Rossi X-ray Timing Explorer during the 2010 outburst, indicating a high energy cutoff of the PLN and a low energy cutoff of the BLN and QPOs around 2 keV. The emergence of the PLN and the fading of the BLN and QPOs initially took place below 2 keV when the source entered the hard intermediate state and settled in the soft state three weeks later. The evolution was accompanied by the emergence of the disk spectral component and decreases in the amplitudes of variability in the soft and hard X-ray bands. Our results indicate that the PLN is associated with an optically thick disk in both hard and intermediate states, and the power spectral state is independent of the X-ray energy spectral state in a broadband view. We suggest that in the hard or intermediate state, the BLN and QPOs emerge from the innermost hot flow subjected to Comptonization, while the PLN originates from the optically thick disk farther out. The energy cutoffs of the PLN and the BLN or QPOs then follow the temperature of the seed photons from the inner edge of the optically thick disk, while the high frequency cutoff of the PLN follows the orbital frequency of the inner edge of the optically thick disk as well.

  9. Raman analysis of cobalt blue pigment in blue and white porcelain: A reassessment

    Science.gov (United States)

    Jiang, Xiaochenyang; Ma, Yanying; Chen, Yue; Li, Yuanqiu; Ma, Qinglin; Zhang, Zhaoxia; Wang, Changsui; Yang, Yimin

    2018-02-01

    Cobalt blue is a famous pigment in human history. In the past decade it is widely reported that the cobalt aluminate has been detected in ancient ceramics as blue colorant in glaze, yet the acquired Raman spectra are incredibly different from that of synthesised references, necessitating a reassessment of such contradictory scenario with more accurate analytic strategies. In this study, micro-Raman spectroscopy (MRS) and scanning electron microscopy (SEM) in association with energy dispersive spectrometry (EDS) were performed on under-glaze cobalt pigments from one submerged blue and white porcelain shard dated from Wanli reign (1573-1620 CE) of Ming dynasty (1365-1644 CE) excavated at Nan'ao I shipwreck off the southern coast of China. The micro-structural inspection reveals that the pigment particles have characteristics of small account, tiny size, heterogeneously distribution, and more importantly, been completely enwrapped by well-developed anorthite crystals in the glaze, indicating that the signals recorded in previous publications are probably not from cobalt pigments themselves but from outside thickset anorthite shell. The further spectromicroscopic analyses confirm this presumption when the accurate spectra of cobalt aluminate pigment and surrounding anorthite were obtained separately with precise optical positioning. Accordingly, we reassess and clarify the previous Raman studies dedicated to cobalt blue pigment in ancient ceramics, e.g. cobalt blue in celadon glaze, and in turn demonstrate the superiority and necessity of coupling spectroscopic analysis with corresponding structure observation, especially in the characterization of pigments from complicated physico-chemical environment like antiquities. Thus, this study promotes a better understanding of Raman spectroscopy study of cobalt blue pigments in art and archaeology field.

  10. Luminous and Variable Stars in M31 and M33. IV. Luminous Blue Variables, Candidate LBVs, B[e] Supergiants, and the Warm Hypergiants: How to Tell Them Apart

    Energy Technology Data Exchange (ETDEWEB)

    Humphreys, Roberta M.; Gordon, Michael S.; Hahn, David [Minnesota Institute for Astrophysics, 116 Church Street SE, University of Minnesota, Minneapolis, MN 55455 (United States); Martin, John C. [University of Illinois Springfield, Springfield, IL 62703 (United States); Weis, Kerstin, E-mail: roberta@umn.edu [Astronomical Institute, Ruhr-Universitaet Bochum (Germany)

    2017-02-10

    In this series of papers we have presented the results of a spectroscopic survey of luminous stars in the nearby spirals M31 and M33. Here, we present spectroscopy of 132 additional stars. Most have emission-line spectra, including luminous blue variables (LBVs) and candidate LBVs, Fe ii emission line stars, the B[e] supergiants, and the warm hypergiants. Many of these objects are spectroscopically similar and are often confused with each other. We examine their similarities and differences and propose the following guidelines that can be used to help distinguish these stars in future work. (1) The B[e] supergiants have emission lines of [O i] and [Fe ii] in their spectra. Most of the spectroscopically confirmed sgB[e] stars also have warm circumstellar dust in their spectral energy distributions (SEDs). (2) Confirmed LBVs do not have the [O i] emission lines in their spectra. Some LBVs have [Fe ii] emission lines, but not all. Their SEDs show free–free emission in the near-infrared but no evidence for warm dust . Their most important and defining characteristic is the S Dor-type variability. (3) The warm hypergiants spectroscopically resemble the LBVs in their dense wind state and the B[e] supergiants. However, they are very dusty. Some have [Fe ii] and [O i] emission in their spectra like the sgB[e] stars, but are distinguished by their A- and F-type absorption-line spectra. In contrast, the B[e] supergiant spectra have strong continua and few if any apparent absorption lines. Candidate LBVs should share the spectral characteristics of the confirmed LBVs with low outflow velocities and the lack of warm circumstellar dust.

  11. Unraveling the Mystery of the Blue Fog: Structure, Properties, and Applications of Amorphous Blue Phase III.

    Science.gov (United States)

    Gandhi, Sahil Sandesh; Chien, Liang-Chy

    2017-12-01

    The amorphous blue phase III of cholesteric liquid crystals, also known as the "blue fog," are among the rising stars in materials science that can potentially be used to develop next-generation displays with the ability to compete toe-to-toe with disruptive technologies like organic light-emitting diodes. The structure and properties of the practically unobservable blue phase III have eluded scientists for more than a century since it was discovered. This progress report reviews the developments in this field from both fundamental and applied research perspectives. The first part of this progress report gives an overview of the 130-years-long scientific tour-de-force that very recently resulted in the revelation of the mysterious structure of blue phase III. The second part reviews progress made in the past decade in developing electrooptical, optical, and photonic devices based on blue phase III. The strong and weak aspects of the development of these devices are underlined and criticized, respectively. The third- and-final part proposes ideas for further improvement in blue phase III technology to make it feasible for commercialization and widespread use. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. "Blue-Collar Blues" : kõigi maade töötud, ühinege! / Ants Juske

    Index Scriptorium Estoniae

    Juske, Ants, 1956-2016

    2009-01-01

    Rahvusvaheline näitus "Blue-Collar Blues" Tallinna Kunstihoones ja Kunstihoone galeriis 31. jaanuarini 2010. Kuraator Anders Härm. Näituse ajendiks on 1. juulist 2009 Eestis kehtima hakanud töölepinguseadus, näituse fookus on töösuhetel

  13. The water use of Indian diets and socio-demographic factors related to dietary blue water footprint.

    Science.gov (United States)

    Harris, Francesca; Green, Rosemary F; Joy, Edward J M; Kayatz, Benjamin; Haines, Andy; Dangour, Alan D

    2017-06-01

    Agriculture accounts for ~90% of India's fresh water use, and there are concerns that future food production will be threatened by insufficient water supply of adequate quality. This study aimed to quantify the water required in the production of diets in India using the water footprint (WF) assessment method. The socio-demographic associations of dietary WFs were explored using mixed effects regression models with a particular focus on blue (irrigation) WF given the importance for Indian agriculture. Dietary data from ~7000 adults living in India were matched to India-specific WF data for food groups to quantify the blue and green (rainfall) WF of typical diets. The mean blue and green WF of diets was 737l/capita/day and 2531l/capita/day, respectively. Vegetables had the lowest WFs per unit mass of product, while roots/tubers had the lowest WFs per unit dietary energy. Poultry products had the greatest blue WFs. Wheat and rice contributed 31% and 19% of the dietary blue WF respectively. Vegetable oils were the highest contributor to dietary green WF. Regional variation in dietary choices meant large differences in dietary blue WFs, whereby northern diets had nearly 1.5 times greater blue WFs than southern diets. Urban diets had a higher blue WF than rural diets, and a higher standard of living was associated with larger dietary blue WFs. This study provides a novel perspective on the WF of diets in India using individual-level dietary data, and demonstrates important variability in WFs due to different food consumption patterns and socio-demographic characteristics. Future dietary shifts towards patterns currently consumed by individuals in higher income groups, would likely increase irrigation requirements putting substantial pressure on India's water resources. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  14. Poporodní blues – česká adaptace dotazníku „Maternity blues questionnaire“

    Czech Academy of Sciences Publication Activity Database

    Takács, L.; Smolík, Filip; Mlíková Seidlerová, J.; Čepický, P.; Hoskovcová, S.

    2016-01-01

    Roč. 81, č. 5 (2016), s. 355-368 ISSN 1210-7832 Institutional support: RVO:68081740 Keywords : EPDS postpartum mood * Maternity Blues Questionnaire * postnatal depression * postpartum blues * postpartum depression Subject RIV: AN - Psychology

  15. Two-color photographic photometry of variables in the globular cluster M28

    International Nuclear Information System (INIS)

    Wehlau, A.; Butterworth, S.

    1990-01-01

    Visual magnitudes have been measured for 20 variables on 32 plates of M28. These have been combined with previously published as well as newly determined blue magnitudes in order to obtain colors for the variables. Blue and visual light curves are presented for 15 of the the variables, including one W Virginis star V4, one RV Tauri star V17, one field Mira variable V7, nine cluster RR Lyrae stars, and three field RR Lyrae stars. It is shown that V14, previously thought to be a c type RR Lyrae star, is to the red of the instability strip. The visual light curve of V9 suggests that the star may be a member of a binary or a very close optical double. Possible evidence for differential reddening in the vicinity of M28 is presented. The bimodal distribution of the periods of the RR Lyrae stars in M28 may indicate a spread in metallicity among the RR Lyrae variables. 16 refs

  16. Long-Period Solar Variability

    Energy Technology Data Exchange (ETDEWEB)

    GAUTHIER,JOHN H.

    2000-07-20

    Terrestrial climate records and historical observations of the Sun suggest that the Sun undergoes aperiodic oscillations in radiative output and size over time periods of centuries and millenia. Such behavior can be explained by the solar convective zone acting as a nonlinear oscillator, forced at the sunspot-cycle frequency by variations in heliomagnetic field strength. A forced variant of the Lorenz equations can generate a time series with the same characteristics as the solar and climate records. The timescales and magnitudes of oscillations that could be caused by this mechanism are consistent with what is known about the Sun and terrestrial climate.

  17. Studying the variability in the Raman signature of writing pen inks.

    Science.gov (United States)

    Braz, André; López-López, María; García-Ruiz, Carmen

    2014-12-01

    This manuscript aims to study the inter and intra brand, model and batch variability in the Raman spectral signature among modern pen inks that will help forensic document examiners during the interpretation process. Results showed that most oil-based samples have similar Raman signatures that are characteristic of the Crystal Violet dye, independently of the brand. Exception was the Pilot samples that use Victoria Pure Blue BO instead. This small inter-brand variability makes oil-based pens difficult to discriminate by brand. On the contrary, gel and liquid-based samples use different colorants such as Rhodamine B, Copper Phthalocyanine, Ethyl Violet and Victoria Blue B. No particular pattern was observed regarding the colorants used by each brand, except the Pilot samples that were the only brand using the Victoria Blue B dye, which is a clear distinct feature. Additionally, the intra-brand variability was also large among gel-based Pilot samples. The small spectral differences observed among several batches of Bic Crystal Medium samples demonstrated that changes were introduced in their chemical formula over the years. The intra-batch variability was small and no spectral differences were observed within batches. This manuscript demonstrates the potential of Raman spectroscopy for discriminating pens inks from different brands and models and even, batches. Additionally, the main colorants used in modern pens were also identified. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  18. 76 FR 22923 - Wellpoint, Inc. D/B/A/Anthem Blue Cross & Blue Shield Enterprise Provider Data Management Team...

    Science.gov (United States)

    2011-04-25

    .../B/A/Anthem Blue Cross & Blue Shield Enterprise Provider Data Management Team Including On-Site... & Blue Shield, Enterprise Provider Data Management Team, Including On-Site Leased Workers From Kelly... Of Kentucky, Enterprise Provider Data Management Team, Louisville, Kentucky TA-W-74,895B Wellpoint...

  19. Fast Blue RR—Siloxane Derivatized Materials Indicate Wound Infection Due to a Deep Blue Color Development

    Directory of Open Access Journals (Sweden)

    Doris Schiffer

    2015-09-01

    Full Text Available There is a strong need for simple and fast methods for wound infection determination. Myeloperoxidase, an immune system-derived enzyme was found to be a suitable biomarker for wound infection. Hence, alkoxysilane-derivatized Fast Blue RR was immobilized via simple hydrolytic polymerization. The resulting enzyme-responsive siloxane layers were incubated with myeloperoxidase, wound fluid or hemoglobin. The reaction was monitored via HPLC measurements and the color development quantified spectrophotometrically. Myeloperoxidase was indeed able to oxidize immobilized Fast Blue RR leading to a blue colored product. No conversion was detected in non-infected wound fluids. The visible color changes of these novel materials towards blue enable an easy distinction between infected and non-infected wound fluids.

  20. Genomic copy number analysis of a spectrum of blue nevi identifies recurrent aberrations of entire chromosomal arms in melanoma ex blue nevus.

    Science.gov (United States)

    Chan, May P; Andea, Aleodor A; Harms, Paul W; Durham, Alison B; Patel, Rajiv M; Wang, Min; Robichaud, Patrick; Fisher, Gary J; Johnson, Timothy M; Fullen, Douglas R

    2016-03-01

    Blue nevi may display significant atypia or undergo malignant transformation. Morphologic diagnosis of this spectrum of lesions is notoriously difficult, and molecular tools are increasingly used to improve diagnostic accuracy. We studied copy number aberrations in a cohort of cellular blue nevi, atypical cellular blue nevi, and melanomas ex blue nevi using Affymetrix's OncoScan platform. Cases with sufficient DNA were analyzed for GNAQ, GNA11, and HRAS mutations. Copy number aberrations were detected in 0 of 5 (0%) cellular blue nevi, 3 of 12 (25%) atypical cellular blue nevi, and 6 of 9 (67%) melanomas ex blue nevi. None of the atypical cellular blue nevi displayed more than one aberration, whereas complex aberrations involving four or more regions were seen exclusively in melanomas ex blue nevi. Gains and losses of entire chromosomal arms were identified in four of five melanomas ex blue nevi with copy number aberrations. In particular, gains of 1q, 4p, 6p, and 8q, and losses of 1p and 4q were each found in at least two melanomas. Whole chromosome aberrations were also common, and represented the sole finding in one atypical cellular blue nevus. When seen in melanomas, however, whole chromosome aberrations were invariably accompanied by partial aberrations of other chromosomes. Three melanomas ex blue nevi harbored aberrations, which were absent or negligible in their precursor components, suggesting progression in tumor biology. Gene mutations involving GNAQ and GNA11 were each detected in two of eight melanomas ex blue nevi. In conclusion, copy number aberrations are more common and often complex in melanomas ex blue nevi compared with cellular and atypical cellular blue nevi. Identification of recurrent gains and losses of entire chromosomal arms in melanomas ex blue nevi suggests that development of new probes targeting these regions may improve detection and risk stratification of these lesions.

  1. Building climate resilience in the Blue Nile/Abay Highlands: Part II-arole for earth system sciences

    Science.gov (United States)

    The Blue Nile (Abay) Highlands of Ethiopia are characterized by significant interannual climate variability, dissected topography and associated local climate contrasts, erosive rains and erodible soils, and intense land pressure due to an increasing population and an economy that is almost entirely...

  2. Analyzing the variability of sediment yield: A case study from paired watersheds in the Upper Blue Nile basin, Ethiopia

    Science.gov (United States)

    Ebabu, Kindiye; Tsunekawa, Atsushi; Haregeweyn, Nigussie; Adgo, Enyew; Meshesha, Derege Tsegaye; Aklog, Dagnachew; Masunaga, Tsugiyuki; Tsubo, Mitsuru; Sultan, Dagnenet; Fenta, Ayele Almaw; Yibeltal, Mesenbet

    2018-02-01

    Improved knowledge of watershed-scale spatial and temporal variability of sediment yields (SY) is needed to design erosion control strategies, particularly in the most severely eroded areas. The present study was conducted to provide this knowledge for the humid tropical highlands of Ethiopia using the Akusity and Kasiry paired watersheds in the Guder portion of the Upper Blue Nile basin. Discharge and suspended sediment concentration data were monitored during the rainy season of 2014 and 2015 using automatic flow stage sensors, manual staff gauges and a depth-integrated sediment sampler. The SY was calculated using empirical discharge-sediment curves for different parts of each rainy season. The measured mean daily sediment concentration differed greatly between years and watersheds (0.51 g L- 1 in 2014 and 0.92 g L- 1 in 2015 for Kasiry, and 1.04 g L- 1 in 2014 and 2.20 g L- 1 in 2015 for Akusity). Sediment concentrations at both sites decreased as the rainy season progressed, regardless of the rainfall pattern, owing to depletion of the sediment supply and limited transport capacity of the flows caused by increased vegetation cover. Rainy season SYs for Kasiry were 7.6 t ha- 1 in 2014 and 27.2 t ha- 1 in 2015, while in Akusity SYs were 25.7 t ha- 1 in 2014 and 71.2 t ha- 1 in 2015. The much larger values in 2015 can be partly explained by increased rainfall and larger peak flow events. The magnitude and timing of peak flow events are major determinants of the amount and variability of SYs. Thus, site-specific assessment of such events is crucial to reveal SY dynamics of small watersheds in tropical highland environments.

  3. The lithium abundance of M67 blue stragglers - A constraint on the blue straggler phenomenon

    International Nuclear Information System (INIS)

    Pritchet, C.J.; Glaspey, J.W.

    1991-01-01

    Upper limits have been placed on the line strength of the 6707 A Li I resonance doublet in seven blue stragglers in M67. The corresponding upper limits on abundances range from log N(Li) less than about 1.3 to less than about 2.3. This result is significantly below the level of log N(Li) about 3.1 + or - 0.1 found in field main-sequence stars of comparable temperature. It is concluded that some form of mixing has affected the outer envelopes of blue stragglers. (Such mixing has been proposed as the mechanism needed to prolong the lifetimes of blue stragglers relative to normal main-sequence stars at the same luminosity). Virtually all mechanisms for the production of blue stragglers other than mixing, binary mass transfer, or binary coalescence appear to be ruled out by the present observations. 45 refs

  4. Ecology of blue straggler stars

    CERN Document Server

    Carraro, Giovanni; Beccari, Giacomo

    2015-01-01

    The existence of blue straggler stars, which appear younger, hotter, and more massive than their siblings, is at odds with a simple picture of stellar evolution. Such stars should have exhausted their nuclear fuel and evolved long ago to become cooling white dwarfs. They are found to exist in globular clusters, open clusters, dwarf spheroidal galaxies of the Local Group, OB associations and as field stars. This book summarises the many advances in observational and theoretical work dedicated to blue straggler stars. Carefully edited extended contributions by well-known experts in the field cover all the relevant aspects of blue straggler stars research: Observations of blue straggler stars in their various environments; Binary stars and formation channels; Dynamics of globular clusters; Interpretation of observational data and comparison with models. The book also offers an introductory chapter on stellar evolution written by the editors of the book.

  5. Natural Blue Food Colour

    DEFF Research Database (Denmark)

    Roda-Serrat, Maria Cinta

    In recent years, there has been a growing tendency to avoid the use of artificial colorants and additives in food products, especially after some studies linked their consumption with behavioural changes in children. However, the incorporation of colorants from natural origin remains a challenge...... for food technologists, as these are typically less vivid and less stable than their synthetic alternatives. Regarding blue colorants, phycocyanins from cyanobacteria are currently in the spotlight as promising new natural blue colorants. Phycocyanins are proteins which blue colour results from...... the presence of the chromophore phycocyanobilin (PCB), a covalently attached linear tetrapyrrole. The applications of phycocyanins as food colorants are however limited, as they show poor stability in certain conditions of pH, light and temperature. Cleavage of PCB from the protein followed by careful product...

  6. A new interpretation of luminous blue stars

    International Nuclear Information System (INIS)

    Stothers, R.

    1976-01-01

    A major revision of current theoretical ideas about the brightest blue stars must be made if Carson's new radiative opacities are adopted in stellar models. Unlike earlier opacities, the new opacities exhibit a large ''bump'' due to CNO ionization, which leads to very strong central condensation, convective instability, and pulsational instability in hot, diffuse stellar envelopes (typically those in which L/M>10 3 solar units). Despite a number of theoretical uncertainties, the new picture of the structure of very luminous stars is reasonably successful in accounting for a variety of previously unexplained observations. Thus, the new stellar models for the phase of core hydrogen burning predict large radii and rather cool effective temperatures (which are yet to be observationally confirmed) for O stars, and a spreading out of the main-sequence band in the H-R diagram toward luminous cool supergiants for masses higher than approx.20 M/sub sun/, beginning at M/sub v/=-4.5 and Sp=B1. They also predict slower surface rotations for O stars compared with B stars; and, in binary systems, slower apsidal motions, closer rotational-revolutional synchronism, and smaller orbital eccentricities. In massive X-ray binary systems, circular orbits and supergiant-like visual companions are expected to be quite common. Radial pulsations of the models have been calculated by employing linearized nonadiabatic pulsation theory. Long-period variability is predicted to exist for massive blue supergiants of luminosity class Ia. The new models for helium stars predict large radii and rather cool effective temperatures for Wolf-Rayet stars, as well as multimodal pulsational instability and, possibly, surface turbulence for these stars. Ultrashort-period variability, observed in many classes of hot luminous stars, may be due, in part, to high radial overtone pulsations (or, possibly, to nonradial pulsation or convective modes)

  7. Intra-population variability of ocean acidification impacts on the physiology of Baltic blue mussels (Mytilus edulis): integrating tissue and organism response.

    Science.gov (United States)

    Stapp, L S; Thomsen, J; Schade, H; Bock, C; Melzner, F; Pörtner, H O; Lannig, G

    2017-05-01

    Increased maintenance costs at cellular, and consequently organism level, are thought to be involved in shaping the sensitivity of marine calcifiers to ocean acidification (OA). Yet, knowledge of the capacity of marine calcifiers to undergo metabolic adaptation is sparse. In Kiel Fjord, blue mussels thrive despite periodically high seawater PCO 2 , making this population interesting for studying metabolic adaptation under OA. Consequently, we conducted a multi-generation experiment and compared physiological responses of F1 mussels from 'tolerant' and 'sensitive' families exposed to OA for 1 year. Family classifications were based on larval survival; tolerant families settled at all PCO 2 levels (700, 1120, 2400 µatm) while sensitive families did not settle at the highest PCO 2 (≥99.8% mortality). We found similar filtration rates between family types at the control and intermediate PCO 2 level. However, at 2400 µatm, filtration and metabolic scope of gill tissue decreased in tolerant families, indicating functional limitations at the tissue level. Routine metabolic rates (RMR) and summed tissue respiration (gill and outer mantle tissue) of tolerant families were increased at intermediate PCO 2 , indicating elevated cellular homeostatic costs in various tissues. By contrast, OA did not affect tissue and routine metabolism of sensitive families. However, tolerant mussels were characterised by lower RMR at control PCO 2 than sensitive families, which had variable RMR. This might provide the energetic scope to cover increased energetic demands under OA, highlighting the importance of analysing intra-population variability. The mechanisms shaping such difference in RMR and scope, and thus species' adaptation potential, remain to be identified.

  8. Can greening of aquaculture sequester blue carbon?

    Science.gov (United States)

    Ahmed, Nesar; Bunting, Stuart W; Glaser, Marion; Flaherty, Mark S; Diana, James S

    2017-05-01

    Globally, blue carbon (i.e., carbon in coastal and marine ecosystems) emissions have been seriously augmented due to the devastating effects of anthropogenic pressures on coastal ecosystems including mangrove swamps, salt marshes, and seagrass meadows. The greening of aquaculture, however, including an ecosystem approach to Integrated Aquaculture-Agriculture (IAA) and Integrated Multi-Trophic Aquaculture (IMTA) could play a significant role in reversing this trend, enhancing coastal ecosystems, and sequestering blue carbon. Ponds within IAA farming systems sequester more carbon per unit area than conventional fish ponds, natural lakes, and inland seas. The translocation of shrimp culture from mangrove swamps to offshore IMTA could reduce mangrove loss, reverse blue carbon emissions, and in turn increase storage of blue carbon through restoration of mangroves. Moreover, offshore IMTA may create a barrier to trawl fishing which in turn could help restore seagrasses and further enhance blue carbon sequestration. Seaweed and shellfish culture within IMTA could also help to sequester more blue carbon. The greening of aquaculture could face several challenges that need to be addressed in order to realize substantial benefits from enhanced blue carbon sequestration and eventually contribute to global climate change mitigation.

  9. The fading of irradiated blue-colored pearls

    International Nuclear Information System (INIS)

    Okamoto, Shinichi

    1982-01-01

    The fading of irradiated and natural blue-colored pearls was investigated in this experiment. Thirty natural blue-colored pearls and sixty irradiated blue-colored pearls were used. Some of them were placed at a light position of RT. Another pearls were placed at a dark position of 50 0 C. The irradiated pearls placed at a light position of RT didn't show remarkable fading in their color in 294 days. But the natural blue-colored pearls showed a little recovery from 4% to 8% in reflection factors in 223 days at RT. The irradiated pearls placed at a dark position of 50 0 C showed the recovery from 9% to 14% in 264 days independently of irradiation times. The natural blue-colored pearls also showed the bleaching from 5% to 10% in reflection factor in 86 days at 50 0 C. Both irradiated and natural blue-colored pearls hardly showed their remarkable changes in their chromaticities independently of temperatures. (author)

  10. Blue space geographies: Enabling health in place.

    Science.gov (United States)

    Foley, Ronan; Kistemann, Thomas

    2015-09-01

    Drawing from research on therapeutic landscapes and relationships between environment, health and wellbeing, we propose the idea of 'healthy blue space' as an important new development Complementing research on healthy green space, blue space is defined as; 'health-enabling places and spaces, where water is at the centre of a range of environments with identifiable potential for the promotion of human wellbeing'. Using theoretical ideas from emotional and relational geographies and critical understandings of salutogenesis, the value of blue space to health and wellbeing is recognised and evaluated. Six individual papers from five different countries consider how health can be enabled in mixed blue space settings. Four sub-themes; embodiment, inter-subjectivity, activity and meaning, document multiple experiences within a range of healthy blue spaces. Finally, we suggest a considerable research agenda - theoretical, methodological and applied - for future work within different forms of blue space. All are suggested as having public health policy relevance in social and public space. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Starbursts in Blue compact dwarf galaxies

    International Nuclear Information System (INIS)

    Thuan, T.X.

    1987-01-01

    We summarize all the arguments for a bursting mode of star formation in blue compact dwarf galaxies. We show in particular how spectral synthesis of far ultraviolet spectra of Blue compact dwarf galaxy constitutes a powerful way for studying the star formation history in these galaxies. Blue compact dwarf galaxy luminosity functions show jumps and discontinuities. These jumps act like fossil records of the star-forming bursts, helping us to count and date the bursts

  12. Hubble's View of Little Blue Dots

    Science.gov (United States)

    Kohler, Susanna

    2018-02-01

    The recent discovery of a new type of tiny, star-forming galaxy is the latest in a zoo of detections shedding light on our early universe. What can we learn from the unique little blue dots found in archival Hubble data?Peas, Berries, and DotsGreen pea galaxies identified by citizen scientists with Galaxy Zoo. [Richard Nowell Carolin Cardamone]As telescope capabilities improve and we develop increasingly deeper large-scale surveys of our universe, we continue to learn more about small, faraway galaxies. In recent years, increasing sensitivity first enabled the detection of green peas luminous, compact, low-mass (10 billion solar masses; compare this to the Milky Ways 1 trillion solar masses!) galaxies with high rates of star formation.Not long thereafter, we discovered galaxies that form stars similarly rapidly, but are even smaller only 330 million solar masses, spanning less than 3,000 light-years in size. These tiny powerhouses were termed blueberries for their distinctive color.Now, scientists Debra and Bruce Elmegreen (of Vassar College and IBM Research Division, respectively) report the discovery of galaxies that have even higher star formation rates and even lower masses: little blue dots.Exploring Tiny Star FactoriesThe Elmegreens discovered these unique galaxies by exploring archival Hubble data. The Hubble Frontier Fields data consist of deep images of six distant galaxy clusters and the parallel fields next to them. It was in the archival data for two Frontier Field Parallels, those for clusters Abell 2744 and MAS J0416.1-2403, that the authors noticed several galaxies that stand out as tiny, bright, blue objects that are nearly point sources.Top: a few examples of the little blue dots recently identified in two Hubble Frontier Field Parallels. Bottom: stacked images for three different groups of little blue dots. [Elmegreen Elmegreen 2017]The authors performed a search through the two Frontier Field Parallels, discovering a total of 55 little blue dots

  13. EXPERIMENTAL RESEARCHES OF ELECTRO-THERMAL RESISTIBILITY OF SEND-OFFS AND CABLES TO ACTION RATIONED ON THE INTERNATIONAL STANDARD OF IEC 62305-1-2010 OF APERIODIC IMPULSE OF CURRENT OF ARTIFICIAL LIGHTNING

    Directory of Open Access Journals (Sweden)

    M.I. Baranov

    2016-03-01

    Full Text Available Purpose. Experimental researches of electro-thermal resistibility of cable-explorer products, applied in the power electric circuits of objects of electric-power industry, to action on its copper and aluminum parts bearings a current rationed on the International Standard of IEC 62305-1-2010 aperiodic impulse 10/350 μs of current of artificial lightning. Methodology. Electrophysics bases of technique of high tensions and high pulsed currents (HPC, and also scientific and technical bases of planning of devices of high-voltage impulsive technique and measuring HPC in them. Results. Experimental a way the quantitative levels of maximal values maximum of possible and critical closenesses of aperiodic impulse 10/350 μs of current of artificial lightning with rationed on the international standard of IEC 62305-1-2010 peak-temporal parameters and admittances on them in copper (aluminum parts bearings a current of send-offs and cables with a polyethylene (PET and polyvinylchloride (PVCH isolation. Originality. First in world practice on the unique powerful high-voltage generator of HPC of artificial lightning experimental researches of resistibility to lightning of pre-production models of send-offs (cables are conducted with copper (aluminum tendons, PET and PVCH by an isolation, in-use in power electric circuits of electric-power industry objects. Practical value. The use in practice of protecting from lightning of the got results will allow substantially to promote functional and fire-prevention safety of engineering communications of objects of industrial electroenergy in the conditions of action on them of short shots of linear lightning.

  14. Molecular evidence for the subspecific differentiation of blue sheep (Pseudois nayaur) and polyphyletic origin of dwarf blue sheep (Pseudois schaeferi).

    Science.gov (United States)

    Tan, Shuai; Zou, Dandan; Tang, Lei; Wang, Gaochao; Peng, Quekun; Zeng, Bo; Zhang, Chen; Zou, Fangdong

    2012-06-01

    Blue sheep (Pseudois nayaur), a Central Asian ungulate with restricted geographic distribution, exhibits unclear variation in morphology and phylogeographic structure. The composition of species and subspecies in the genus Pseudois is controversial, particularly with respect to the taxonomic designation of geographically restricted populations. Here, 26 specimens including 5 dwarf blue sheep (Pseudois schaeferi), which were collected from a broad geographic region in China, were analyzed for 2 mitochondrial DNA fragments (cytochrome b and control region sequences). In a pattern consistent with geographically defined subspecies, we found three deeply divergent mitochondrial lineages restricted to different geographic regions. The currently designated two subspecies of blue sheep, Pseudois nayaur nayaur and Pseudois nayaur szechuanensis, were recognized in the phylogenetic trees. In addition, the Helan Mountain population showed distinct genetic characteristics from other geographic populations, and thus should be classified as a new subspecies. In contrast, dwarf blue sheep clustered closely with some blue sheep from Sichuan Province in the phylogenetic trees. Therefore, dwarf blue sheep appear to be a subset of Pseudois nayaur szechuanensis. After considering both population genetic information and molecular clock analysis, we obtained some relevant molecular phylogeographic information concerning the historical biogeography of blue sheep. These results also indicate that western Sichuan was a potential refugium for blue sheep during the Quaternary period.

  15. Movements of Blue Sharks (Prionace glauca) across Their Life History

    Science.gov (United States)

    Vandeperre, Frederic; Aires-da-Silva, Alexandre; Fontes, Jorge; Santos, Marco; Serrão Santos, Ricardo; Afonso, Pedro

    2014-01-01

    Spatial structuring and segregation by sex and size is considered to be an intrinsic attribute of shark populations. These spatial patterns remain poorly understood, particularly for oceanic species such as blue shark (Prionace glauca), despite its importance for the management and conservation of this highly migratory species. This study presents the results of a long-term electronic tagging experiment to investigate the migratory patterns of blue shark, to elucidate how these patterns change across its life history and to assess the existence of a nursery area in the central North Atlantic. Blue sharks belonging to different life stages (n = 34) were tracked for periods up to 952 days during which they moved extensively (up to an estimated 28.139 km), occupying large parts of the oceanic basin. Notwithstanding a large individual variability, there were pronounced differences in movements and space use across the species' life history. The study provides strong evidence for the existence of a discrete central North Atlantic nursery, where juveniles can reside for up to at least 2 years. In contrast with previously described nurseries of coastal and semi-pelagic sharks, this oceanic nursery is comparatively vast and open suggesting that shelter from predators is not its main function. Subsequently, male and female blue sharks spatially segregate. Females engage in seasonal latitudinal migrations until approaching maturity, when they undergo an ontogenic habitat shift towards tropical latitudes. In contrast, juvenile males generally expanded their range southward and apparently displayed a higher degree of behavioural polymorphism. These results provide important insights into the spatial ecology of pelagic sharks, with implications for the sustainable management of this heavily exploited shark, especially in the central North Atlantic where the presence of a nursery and the seasonal overlap and alternation of different life stages coincides with a high fishing

  16. The discrimination of (non-denim) blue cotton.

    Science.gov (United States)

    Palmer, Ray; Hutchinson, William; Fryer, Verity

    2009-03-01

    This study was conducted to determine the degree of discrimination obtained between non-denim blue cotton fibres using visible-UV range microspectrophotometry alone. To this end, samples of fibres were taken from 100, nondenim, blue cotton, outer garments, including t-shirts, trousers and jumpers and subjected to analysis by both visible and UV range microspectrophotometry. The results obtained from the samples of each garment were compared to determine if they 'matched' or not. From an initial visual comparison of the garments it was possible to subdivide the samples into two populations consisting of 73 'dark blue' garments and 27 'mid-blue' garments. It was found that of the 73 'dark blue' garments, 22 distinct sub-populations could be distinguished using visible range MSP, this figure being increased to 43 when the analysis was extended into the UVW range. In the case of the 27 'mid-blue' garments, 9 distinct sub-populations were discriminated using visible range MSP, this figure being increased to 17 when the analysis was extended into the UV range. The discriminating power (i.e., the number of discriminated pairs divided by the number of possible pairs) of visible range microspectrophotometry was calculated as 0.89 for 'mid-blue' garments and 0.87 for 'dark blue' garments. Extending microspectrophotometry into the UV range increased discrimination by 7%, giving a discriminating power of 0.96 for both mid and dark blue cotton fibres which was similar to that reported by a previous study where this method was combined with light and fluorescence microscopy. Intra-garment variation was found to be negligible. The implications of this study for casework are discussed and a revised analytical pathway for the comparison of this fibre type/colour combination using microspectrophotometry as a primary screening tool, is proposed.

  17. BLUES function method in computational physics

    Science.gov (United States)

    Indekeu, Joseph O.; Müller-Nedebock, Kristian K.

    2018-04-01

    We introduce a computational method in physics that goes ‘beyond linear use of equation superposition’ (BLUES). A BLUES function is defined as a solution of a nonlinear differential equation (DE) with a delta source that is at the same time a Green’s function for a related linear DE. For an arbitrary source, the BLUES function can be used to construct an exact solution to the nonlinear DE with a different, but related source. Alternatively, the BLUES function can be used to construct an approximate piecewise analytical solution to the nonlinear DE with an arbitrary source. For this alternative use the related linear DE need not be known. The method is illustrated in a few examples using analytical calculations and numerical computations. Areas for further applications are suggested.

  18. GROWTH PERFORMANCE AND MEAT QUALITY OF DOMESTICATED BLUE SWIMMING CRAB (Portunus pelagicus)

    OpenAIRE

    Fujaya, Yushinta; Trijuno, Dody Dharmawan; Aslamyah, Siti; Alam, Nur

    2015-01-01

    Blue Swimming Crab (Portunus pelagicus) is one of the commercial crabs traded widely around the world. But, crab aquaculture has not made a significant contribution in meeting the increasing overseas market demand. Some constraints in crab cultivation were high mortality, low and variable growth rate, and low of meat quality. The aims of this research were to produce a superior broodstock through domestication and selective breeding. Superior broodstock was expected to produce a high qual...

  19. New insights into the role of Mn and Fe in coloring origin of blue decorations of blue-and-white porcelains by XANES spectroscopy

    International Nuclear Information System (INIS)

    Zhu, Jian; Luo, Wugan; Ming, Chaofang; Wang, Changsui; Chen, Dongliang; Xu, Wei; Wang, Lihua

    2013-01-01

    Blue and white porcelain is one of the most valuable ancient ceramics varieties in ancient China. It is well known for its beautiful blue decorations. However, the origin of its blue color has not been very clear till now. In this research, two blue and white porcelains from Jingdezhen, Jiangxi province were selected and Mn and Fe K-edge XANES spectra were recorded from blue decorations with or without transparent glaze. Results showed that Mn K-edge XANES features were almost identical between different samples while that of iron changed. The above findings indicated the positive role of iron in the variation of blue decorations. As for manganese, although more system researches were need, its negative role on the variations of the tone of blue decorations was obtained. On the other hand, the paper also revealed the XAFS results will be affect by the glaze layer above the pigment. These findings provided us more information to understand the coloring origin of blue decorations of blue-and-white porcelain by means of XANES spectroscopy.

  20. New insights into the role of Mn and Fe in coloring origin of blue decorations of blue-and-white porcelains by XANES spectroscopy

    Science.gov (United States)

    Zhu, Jian; Luo, Wugan; Chen, Dongliang; Xu, Wei; Ming, Chaofang; Wang, Changsui; Wang, Lihua

    2013-04-01

    Blue and white porcelain is one of the most valuable ancient ceramics varieties in ancient China. It is well known for its beautiful blue decorations. However, the origin of its blue color has not been very clear till now. In this research, two blue and white porcelains from Jingdezhen, Jiangxi province were selected and Mn and Fe K-edge XANES spectra were recorded from blue decorations with or without transparent glaze. Results showed that Mn K-edge XANES features were almost identical between different samples while that of iron changed. The above findings indicated the positive role of iron in the variation of blue decorations. As for manganese, although more system researches were need, its negative role on the variations of the tone of blue decorations was obtained. On the other hand, the paper also revealed the XAFS results will be affect by the glaze layer above the pigment. These findings provided us more information to understand the coloring origin of blue decorations of blue-and-white porcelain by means of XANES spectroscopy.

  1. Nature's palette: the search for natural blue colorants.

    Science.gov (United States)

    Newsome, Andrew G; Culver, Catherine A; van Breemen, Richard B

    2014-07-16

    The food and beverage industry is seeking to broaden the palette of naturally derived colorants. Although considerable effort has been devoted to the search for new blue colorants in fruits and vegetables, less attention has been directed toward blue compounds from other sources such as bacteria and fungi. The current work reviews known organic blue compounds from natural plant, animal, fungal, and microbial sources. The scarcity of blue-colored metabolites in the natural world relative to metabolites of other colors is discussed, and structural trends common among natural blue compounds are identified. These compounds are grouped into seven structural classes and evaluated for their potential as new color additives.

  2. Evidence for deterministic chaos in aperiodic oscillations of acute lymphoblastic leukemia cells in long-term culture

    Science.gov (United States)

    Lambrou, George I.; Chatziioannou, Aristotelis; Vlahopoulos, Spiros; Moschovi, Maria; Chrousos, George P.

    Biological systems are dynamic and possess properties that depend on two key elements: initial conditions and the response of the system over time. Conceptualizing this on tumor models will influence conclusions drawn with regard to disease initiation and progression. Alterations in initial conditions dynamically reshape the properties of proliferating tumor cells. The present work aims to test the hypothesis of Wolfrom et al., that proliferation shows evidence for deterministic chaos in a manner such that subtle differences in the initial conditions give rise to non-linear response behavior of the system. Their hypothesis, tested on adherent Fao rat hepatoma cells, provides evidence that these cells manifest aperiodic oscillations in their proliferation rate. We have tested this hypothesis with some modifications to the proposed experimental setup. We have used the acute lymphoblastic leukemia cell line CCRF-CEM, as it provides an excellent substrate for modeling proliferation dynamics. Measurements were taken at time points varying from 24h to 48h, extending the assayed populations beyond that of previous published reports that dealt with the complex dynamic behavior of animal cell populations. We conducted flow cytometry studies to examine the apoptotic and necrotic rate of the system, as well as DNA content changes of the cells over time. The cells exhibited a proliferation rate of nonlinear nature, as this rate presented oscillatory behavior. The obtained data have been fit in known models of growth, such as logistic and Gompertzian growth.

  3. Influence of altitude on the height of blue cone in a premixed flame

    Energy Technology Data Exchange (ETDEWEB)

    Amell, Andres A. [Gas Science and Technology Group, Engineering Faculty, University of Antioquia, Calle 67 No. 53-108 Bloque 20-435, Medellin (Colombia)

    2007-02-15

    For economic and environmental reasons natural gas begins to take an important participation as an energy source in the residential sector of Latin American cities placed at high altitudes: La Paz (3719m), Santa Fe de Bogota (2600m), Mexico City (2240m), Manizales (2150m), Medellin (1550m), Cali (1000m) and others. One of the most widely used natural gas systems in the residential sector is the partially aerated burner. The height of the blue cone in a premixed flame increases as the altitude above sea level becomes greater. In this work this behavior is determined experimentally, for this purpose tests were carried out in colombian location placed at 40, 550, 1220, 2040 and 2550m above sea level. In every place of tests three replicas were performed, keeping constant the following variables: chemical composition of natural gas, with a methane content of 98%, gas pressure discharge at the injector at 20mbar, injector diameter in 1.35mm, mixer geometry and port diameter in 17mm. The images of the blue cone were captured with a Pixera digital camera for images registration. Images were stored to determine later, through the software Matrox Inspector for images analysis, the height of the blue cone in each experiment for the different altitudes. It was found that the height of the blue cone is increased in 1.49+/-0.12mm by each 304m (1000feet) rise in altitude. (author)

  4. On the K-term and dispersion ratios of semi-regular variables

    International Nuclear Information System (INIS)

    Aslan, Z.

    1981-01-01

    Optical velocities of semi-regular (SR) and irregular (Lb) variables are analysed for a K-term. There is evidence for a dependence upon stellar period. Absorption lines in shorter period non-emission SR variables are blue-shifted relative to the centre-of-mass velocity by about 6 +- 3 km s -1 . Emission-line SR variables give a non-negative absorption K-term and Lb variables give no K-terms other than zero. Comparison is made with the K-terms implied by the OH velocity pattern in long-period variables. Dispersion ratios are also calculated. (author)

  5. Quasi-periodic Pulse Amplitude Modulation in the Accreting Millisecond Pulsar IGR J00291+5934

    Energy Technology Data Exchange (ETDEWEB)

    Bult, Peter [Astrophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Doesburgh, Marieke van; Klis, Michiel van der [Anton Pannekoek Institute, University of Amsterdam, Postbus 94249, 1090 GE Amsterdam (Netherlands)

    2017-08-20

    We introduce a new method for analyzing the aperiodic variability of coherent pulsations in accreting millisecond X-ray pulsars (AMXPs). Our method involves applying a complex frequency correction to the time-domain light curve, allowing for the aperiodic modulation of the pulse amplitude to be robustly extracted in the frequency domain. We discuss the statistical properties of the resulting modulation spectrum and show how it can be correlated with the non-pulsed emission to determine if the periodic and aperiodic variability are coupled processes. Using this method, we study the 598.88 Hz coherent pulsations of the AMXP IGR J00291+5934 as observed with the Rossi X-ray Timing Explorer and XMM-Newton . We demonstrate that our method easily confirms the known coupling between the pulsations and a strong 8 mHz quasi-periodic oscillation (QPO) in XMM-Newton observations. Applying our method to the RXTE observations, we further show, for the first time, that the much weaker 20 mHz QPO and its harmonic are also coupled with the pulsations. We discuss the implications of this coupling and indicate how it may be used to extract new information on the underlying accretion process.

  6. Phototherapy with blue and green mixed-light is as effective against unconjugated jaundice as blue light and reduces oxidative stress in the Gunn rat model.

    Science.gov (United States)

    Uchida, Yumiko; Morimoto, Yukihiro; Uchiike, Takao; Kamamoto, Tomoyuki; Hayashi, Tamaki; Arai, Ikuyo; Nishikubo, Toshiya; Takahashi, Yukihiro

    2015-07-01

    Phototherapy using blue light-emitting diodes (LED) is effective against neonatal jaundice. However, green light phototherapy also reduces unconjugated jaundice. We aimed to determine whether mixed blue and green light can relieve jaundice with minimal oxidative stress as effectively as either blue or green light alone in a rat model. Gunn rats were exposed to phototherapy with blue (420-520 nm), filtered blue (FB; 440-520 nm without 1.00), respectively. Blue plus green phototherapy is as effective as blue phototherapy and it attenuates irradiation-induced oxidative stress. Combined blue and green spectra might be effective against neonatal hyperbilirubinemia. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  7. MOCK OBSERVATIONS OF BLUE STRAGGLERS IN GLOBULAR CLUSTER MODELS

    International Nuclear Information System (INIS)

    Sills, Alison; Glebbeek, Evert; Chatterjee, Sourav; Rasio, Frederic A.

    2013-01-01

    We created artificial color-magnitude diagrams of Monte Carlo dynamical models of globular clusters and then used observational methods to determine the number of blue stragglers in those clusters. We compared these blue stragglers to various cluster properties, mimicking work that has been done for blue stragglers in Milky Way globular clusters to determine the dominant formation mechanism(s) of this unusual stellar population. We find that a mass-based prescription for selecting blue stragglers will select approximately twice as many blue stragglers than a selection criterion that was developed for observations of real clusters. However, the two numbers of blue stragglers are well-correlated, so either selection criterion can be used to characterize the blue straggler population of a cluster. We confirm previous results that the simplified prescription for the evolution of a collision or merger product in the BSE code overestimates their lifetimes. We show that our model blue stragglers follow similar trends with cluster properties (core mass, binary fraction, total mass, collision rate) as the true Milky Way blue stragglers as long as we restrict ourselves to model clusters with an initial binary fraction higher than 5%. We also show that, in contrast to earlier work, the number of blue stragglers in the cluster core does have a weak dependence on the collisional parameter Γ in both our models and in Milky Way globular clusters

  8. Alcian blue-stained particles in a eutrophic lake

    DEFF Research Database (Denmark)

    Worm, J.; Søndergaard, Morten

    1998-01-01

    We used a neutral solution of Alcian Blue to stain transparent particles in eutrophic Lake Frederiksborg Slotss0, Denmark. Alcian Blue-stained particles (ABSP) appeared to be similar to the so-called transparent exopolymer particles (TEP) identified with an acidic solution of Alcian Blue. Our...

  9. FIXED-BED COLUMN ADSORPTION OF METHYL BLUE USING ...

    African Journals Online (AJOL)

    userpc

    Axle Wood Carbon (AWC) was used to study the removal of Methyl Blue (MB) from ... height, initial methyl blue (MB) concentration, .... colour from blue to dark purple- .... Environ. Earth Sci. 13; 1–13. Yagub, M. T., Sen, T. K., Afroze, S., and Ang,.

  10. Blue light-induced oxidative stress in live skin.

    Science.gov (United States)

    Nakashima, Yuya; Ohta, Shigeo; Wolf, Alexander M

    2017-07-01

    Skin damage from exposure to sunlight induces aging-like changes in appearance and is attributed to the ultraviolet (UV) component of light. Photosensitized production of reactive oxygen species (ROS) by UVA light is widely accepted to contribute to skin damage and carcinogenesis, but visible light is thought not to do so. Using mice expressing redox-sensitive GFP to detect ROS, blue light could produce oxidative stress in live skin. Blue light induced oxidative stress preferentially in mitochondria, but green, red, far red or infrared light did not. Blue light-induced oxidative stress was also detected in cultured human keratinocytes, but the per photon efficacy was only 25% of UVA in human keratinocyte mitochondria, compared to 68% of UVA in mouse skin. Skin autofluorescence was reduced by blue light, suggesting flavins are the photosensitizer. Exposing human skin to the blue light contained in sunlight depressed flavin autofluorescence, demonstrating that the visible component of sunlight has a physiologically significant effect on human skin. The ROS produced by blue light is probably superoxide, but not singlet oxygen. These results suggest that blue light contributes to skin aging similar to UVA. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Compact and efficient blue laser sheet for measurement

    Science.gov (United States)

    Qi, Yan; Wang, Yu; Wu, Bin; Wang, Yanwei; Yan, Boxia

    2017-10-01

    Compact and efficient blue laser sheet has important applications in the field of measurement, with laser diode end pumped Nd:YAG directly and LBO intracavity frequency doubling, a compact and efficient CW 473nm blue laser sheet composed of dual path liner blue laser is realized. At an incident pump power of 12.4W, up to 1.4W output power of the compound blue laser is achieved, the optical-to-optical conversion efficiency is as high as 11.3%.

  12. The Structure of the Blue Whirl

    Science.gov (United States)

    Hariharan, Sriram Bharath; Hu, Yu; Xiao, Huahua; Gollner, Michael; Oran, Elaine

    2017-11-01

    Recent experiments have led to the discovery of the blue whirl, a small, stable regime of the fire whirl that burns typically sooty liquid hydrocarbons without producing soot. The physical structure consists of three regions - the blue cone, the vortex rim and the purple haze. The physical nature of the flame was further investigated through digital imaging techniques, which suggest that the transition (from the fire whirl to the blue whirl) and shape of the flame may be influenced by vortex breakdown. The flame was found to develop over a variety of surfaces, which indicates that the formation of the blue whirl is strongly influenced by the flow structure over the incoming boundary layer. The thermal structure was investigated using micro-thermocouples, thin-filament pyrometry and OH* spectroscopy. These revealed a peak temperature around 2000 K, and that most of the combustion occurs in the relatively small, visibly bright vortex rim. The results of these investigations provide a platform to develop a theory on the structure of the blue whirl, a deeper understanding of which may affirm potential for applications in the energy industry. This work was supported by an NSF EAGER award and Minta Martin Endowment Funds in the Department of Aerospace Engineering at the University of Maryland.

  13. Blue whales Balaenoptera musculus off Angola: recent sightings ...

    African Journals Online (AJOL)

    Further survey work is required to better clarify the status of blue whales in Angolan waters, particularly with regard to population structure and potential calving grounds. Keywords: Antarctic blue whale, calving, catch data, pygmy blue whale, South-East Atlantic, stomach contents. African Journal of Marine Science 2014, ...

  14. Geothermal Technologies Program Blue Ribbon Panel Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2011-06-17

    The Geothermal Technologies Program assembled a geothermal Blue Ribbon Panel on March 22-23, 2011 in Albuquerque, New Mexico for a guided discussion on the future of geothermal energy in the United States and the role of the DOE Program. The Geothermal Blue Ribbon Panel Report captures the discussions and recommendations of the experts. An addendum is available here: http://www.eere.energy.gov/geothermal/pdfs/gtp_blue_ribbon_panel_report_addendum10-2011.pdf

  15. Spectra and ages of blue stragglers

    International Nuclear Information System (INIS)

    Abt, H.A.

    1985-01-01

    A mechanism similar to Wheeler's quasi-homogeneous evolution and Finzi and Wolf's proposal for blue stragglers is proposed as the origin of the blue stragglers in intermediate-age clusters. Blue stragglers are stars whose positions in color-magnitude diagrams of open and globular clusters are significantly above the turn-off points and in the region of the (former) main sequence; they seem to represent a conflict with the general conclusion that all stars in a cluster originated at about the same time. It is concluded that there are at least two kinds of blue stragglers: (1) those stars of types about B3-A2 are primarily Ap stars and slow rotators, occur in the intermediate age clusters and remain in the main sequence region probably through magnetic mixing; and (2) the stars of type O6-B2 frequently have emission lines, are rapid rotators, occur in the young cluster, and remain in the main sequence region probably by rotational mixing. 30 references

  16. Characteristics of Alcian-blue Dye Adsorption of Natural Biofilm Matrix

    Science.gov (United States)

    Kurniawan, A.; Yamamoto, T.; Sukandar; Guntur

    2018-01-01

    In this study, natural biofilm matrices formed on stones have been used for the adsorption of Alcian blue dye. Alcian blue is a member of polyvalent basic dyes that largely used from laboratory until industrial dying purposes. The adsorption of the dye onto the biofilm matrix has been carried out at different experimental conditions such as adsorption isotherm and kinetic of adsorption. The electric charge properties of biofilm matrix and its changes related to the adsorption of Alcian blue have been also investigated. Moreover, the results of Alcian blue adsorption to the biofilm were compared to those onto the acidic and neutral resin. The kinetics of adsorption result showed that the adsorption of the Alcian blue dye reached to a maximum adsorption amount within 60 minutes. The adsorption amount of Alcian blue to biofilm increased monotonously, and the maximum adsorption amount was greater compared to the resins. On the contrary, Alcian blue did not attach to the neutral resin having no electric charge. It seems that Alcian blue attached to the acidic resins due to electrostatic attractive force, and the same seems to be the case for adsorption of Alcian blue to biofilm. The adsorption of Alcian blue to the biofilm and acidic resins fitted to Langmuir type indicates that the binding of Alcian blue to the biofilm and acidic resins occurred in a monolayer like form. The maximum adsorption amount of Alcian blue on the biofilm (0.24 mmol/dry-g) was greater than those of acidic resin (0.025 mmol/dry-g). This indicates that the biofilm has many more sites for Alcian blue attachment than acidic resins. According to the result of this study, the biofilm matrix can be a good adsorbent for dye such as Alcian blue or other dyes that causing hazards in nature.

  17. Effects of blue light and caffeine on mood.

    Science.gov (United States)

    Ekström, Johan G; Beaven, C Martyn

    2014-09-01

    Both short wavelength (blue) light and caffeine have been studied for their mood enhancing effects on humans. The ability of blue light to increase alertness, mood and cognitive function via non-image forming neuropathways has been suggested as a non-pharmacological countermeasure for depression across a range of occupational settings. This experimental study compared blue light and caffeine and aimed to test the effects of blue light/placebo (BLU), white light/240-mg caffeine (CAF), blue light/240-mg caffeine (BCAF) and white light/placebo (PLA), on mood. A randomised, controlled, crossover design study was used, in a convenience population of 20 healthy volunteers. The participants rated their mood on the Swedish Core Affect Scales (SCAS) prior to and after each experimental condition to assess the dimensions of valence and activation. There was a significant main effect of light (p = 0.009), and the combination of blue light and caffeine had clear positive effects on core effects (ES, ranging from 0.41 to 1.20) and global mood (ES, 0.61 ± 0.53). The benefits of the combination of blue light and caffeine should be further investigated across a range of applications due to the observed effects on the dimensions of arousal, valence and pleasant activation.

  18. Occupational contact dermatitis in blue-collar workers

    DEFF Research Database (Denmark)

    Schwensen, Jakob F; Menné, Torkil; Veien, Niels K

    2014-01-01

    BACKGROUND: Blue-collar workers have a high risk of occupational contact dermatitis, but epidemiological studies are scarce. OBJECTIVES: To investigate allergic contact dermatitis in blue-collar workers with dermatitis registered by the Danish Contact Dermatitis Group. METHODS: A retrospective...... analysis of patch test data from 1471 blue-collar workers and 1471 matched controls tested between 2003 and 2012 was performed. A logistic regression was used to test for associations. RESULTS: The blue-collar workers often had occupational hand dermatitis (p dermatitis was less commonly......, and methylchloroisothiazolinone (MCI)/methylisothiazolinone (MI). The following occupations were additionally identified as risk factors for contact sensitization to MCI/MI and MI, epoxy resins, and potassium dichromate, respectively: painting, construction work, and tile setting/terrazzo work. CONCLUSION: Contact allergy...

  19. The Online Big Blue Test for Promoting Exercise: Health, Self-Efficacy, and Social Support.

    Science.gov (United States)

    Gómez-Zúñiga, Beni; Pousada, Modesta; Hernandez, Manny M; Colberg, Sheri; Gabarrón, Elia; Armayones, Manuel

    2015-10-01

    Recent articles have documented the influence of self-efficacy and social support on exercising. Simultaneously, insulin use is also related to the perception of self-efficacy and social support in patients with diabetes. We combine these two ideas through the Big Blue Test experience in a social networking site and propose to analyze whether a change in blood sugar levels after completion of the Big Blue Test and insulin use are related to the perception of self-efficacy and social support in patients with diabetes. To undergo the Big Blue Test, 3,926 participants voluntarily joined the Diabetes Hands Foundation. Responses were analyzed using descriptive analysis. The participants who reduced their blood glucose after exercise the least were those with lower self-efficacy and also with lower perceived social support. There seems to have been no relationship between changes in blood sugar level and the explicit intention of doing exercise in the future. Insulin-dependent participants demonstrated a lower perception of self-efficacy and social support than non-insulin-dependent participants. Change in blood glucose level or being insulin-dependent or not do not explain completely a health behavior such as exercise. Hence, self-efficacy and social support have an impact on behavioral change such as exercise to become a habit in people with diabetes, and this experience through a social networking site is an important tool for this behavioral change. For exercise to become a habit in people with diabetes, it is necessary to consider not only the crucial physiological variables, but also those psychological variables that clearly have an impact on behavioral change.

  20. Cholesteric liquid crystals: the blue phase and the analogy with 3He-A

    International Nuclear Information System (INIS)

    Wright, D.C.

    1983-01-01

    Part I of this thesis presents a unified view of some of the theoretical progress on the blue phase of cholesteric liquid crystals. The elastic and bulk cholesteric energies are found to be separately minimized by different forms of the order parameter, and the problem of minimizing the full free energy can be viewed as a competition between these incompatible forms. Near the transition to the high temperature disordered phase, the bulk and elastic contributions may be comparable, and complicated, non-uniform structures can appear as compromise solutions to the minimization problem. These structures are interpreted as the blue phases. The two predominant models for the blue phase, which use either a director or second rank tensor order parameter, are seen in this picture as forms applicable in two limits, when the transition from the disordered phase is strongly and weakly first order, respectively. Both methods of constructing the order parameters, and the relation between them, is presented. Part II of this thesis concerns the problem of describing long wavelength distortions in cholesterics. A proposed analogy between cholesterics and superfluid 3 He-A, with the uniform twist in cholesterics corresponding to stable superflow in helium is considered. The difficulty with such a description lies in attempting to define variables which are well-defined in the distorted system and which vary slowly enough to justify a gradient expansion of the distortion energy. By requiring the variables in such a theory to be slowly varying, as in the superfluid case, only director configurations which are not stationary points of the free energy can be described. A solution is proposed which includes rapid variations of the director and corrects this description in such a way to satisfy the stationary conditions

  1. Degradation of phosphorescent blue organic light-emitting diodes

    Energy Technology Data Exchange (ETDEWEB)

    Chiu, Chien-Shu [Department of Electrical Engineering and Information Technology, Technical University of Braunschweig (Germany); Siemens AG, CT MM 1, Erlangen (Germany); Steinbacher, Frank [Department of Materials Science VI, University of Erlangen-Nuernberg (Germany); Siemens AG, CT MM 1, Erlangen (Germany); Krause, Ralf; Hunze, Arvid [Siemens AG, CT MM 1, Erlangen (Germany); Kowalsky, Wolfgang [Department of Electrical Engineering and Information Technology, Technical University of Braunschweig (Germany)

    2009-07-01

    Development of phosphorescent materials has significantly improved the efficiency of organic light-emitting diodes (OLEDs). By using efficient red, green and blue phosphorescent emitter materials high efficient white OLEDs can be achieved. However, due to low stability of blue phosphorescent materials the lifetime of phosphorescent white OLEDs remains an issue. As a result, degradation of blue phosphorescent materials needs to be further investigated and improved. In this work, blue OLED devices based on the phosphorescent emitter FIrpic were investigated. Single-carrier hole-only as well as electron-only devices were fabricated. For investigation of degradation process the devices were stressed with electrical current and UV-light to study the impact of charge carriers as well as excitons and exciton-polaron quenching on the stability of the blue dye.

  2. Effects of Watershed Land Use and Geomorphology on Stream Low Flows During Severe Drought Conditions in the Southern Blue Ridge Mountains, Georgia and North Carolina, United States

    Science.gov (United States)

    Land use and physiographic variability influence stream low flows, yet their interactions and relative influence remain unresolved. Our objective was to assess the influence of land use and watershed geomorphic characteristics on low-flow variability in the southern Blue Ridge Mo...

  3. Crystalline liquids: the blue phases

    Science.gov (United States)

    Wright, David C.; Mermin, N. David

    1989-04-01

    The blue phases of cholesteric liquid crystals are liquids that exhibit orientational order characterized by crystallographic space-group symmetries. We present here a pedagogical introduction to the current understanding of the equilibrium structure of these phases accompanied by a general overview of major experimental results. Using the Ginzburg-Landau free energy appropriate to the system, we first discuss in detail the character and stability of the usual helical phase of cholesterics, showing that for certain parameter ranges the helical phase is unstable to the appearance of one or more blue phases. The two principal models for the blue phases are two limiting cases of the Ginzburg-Landau theory. We explore each limit and conclude with some general considerations of defects in both models and an exact minimization of the free energy in a curved three-dimensional space.

  4. Intraoral blue (Jadassohn-Tieche) nevus.

    Science.gov (United States)

    Hasse, C D; Zoutendam, G L; Gombas, O F

    1978-05-01

    Blue nevus of the oral mucosa is a distinctly uncommon clincial entity. Careful review of the literature yielded thirty-one previously reported cases. The present article reports the occurrence of a blue nevus of the hard palate in a 58-year-old man. It is of interest since it is the smallest (1 by 1 mm.) intraoral blue nevus to be reported. A clinicopathologic study of the previous thirty-one cases and of our case suggests that this lesion has no age or sex predilection. The most common site of occurrence was the hard palate. There appears to be no tendency toward recurrence. A brief review of the historical background, clinical features, theories of possible origin, and differential diagnosis is presented. Excisional biopsy of localized areas of oral pibmentation, together with histopathologic study, is indicated to rule out melanoma.

  5. New York Blue

    Data.gov (United States)

    Federal Laboratory Consortium — New York Blue is used cooperatively by the Laboratory and Stony Brook University as part of the New York Center for Computation Sciences. Ranked as the 28th fastest...

  6. The secret of the blue fog

    Science.gov (United States)

    Henrich, Oliver; Marenduzzo, Davide

    2017-04-01

    Why certain liquids turn blue when cooled was a mystery that stumped scientists for more than a century. As Oliver Henrich and Davide Marenduzzo explain, solving the secret of the “blue fog” proved to be an intellectual tour de force - and one that could lead to new types of display devices

  7. Tapered photonic crystal fibers for blue-enhanced supercontinuum generation

    DEFF Research Database (Denmark)

    Møller, Uffe; Sørensen, Simon Toft; Larsen, Casper

    2012-01-01

    Tapering of photonic crystal fibers is an effective way of shifting the blue edge of a supercontinuum spectrum down in the deep-blue. We discuss the optimum taper profile for enhancing the power in the blue edge....

  8. A Rare Case of Multifocal Prostatic Blue Nevus

    Directory of Open Access Journals (Sweden)

    Elias J. Farran

    2018-01-01

    Full Text Available Prostatic blue nevus is a rare benign pathologic diagnosis most commonly diagnosed incidentally on many different types of prostate specimens. Blue nevus is the deposition of stromal melanin characterized by spindle cells within the fibromuscular stroma which stains positive for melanin-specific stains Fontana-Masson and S100 and stains negative for CD68, HMB45, and iron stains. We report the case of a multifocal and bilateral blue nevus in a 52-year-old Hispanic male who presented with an elevated prostate-specific antigen of 4.3 and mild obstructive lower urinary tract symptoms, found by transrectal ultrasound-guided prostate needle biopsy. The biopsy also revealed benign prostatic tissue with postatrophic hyperplasia and chronic inflammation. This is the 35th reported case of prostatic blue nevus and the third to show multifocal blue nevus.

  9. Blue Light Protects Against Temporal Frequency Sensitive Refractive Changes.

    Science.gov (United States)

    Rucker, Frances; Britton, Stephanie; Spatcher, Molly; Hanowsky, Stephan

    2015-09-01

    Time spent outdoors is protective against myopia. The outdoors allows exposure to short-wavelength (blue light) rich sunlight, while indoor illuminants can be deficient at short-wavelengths. In the current experiment, we investigate the role of blue light, and temporal sensitivity, in the emmetropization response. Five-day-old chicks were exposed to sinusoidal luminance modulation of white light (with blue; N = 82) or yellow light (without blue; N = 83) at 80% contrast, at one of six temporal frequencies: 0, 0.2, 1, 2, 5, 10 Hz daily for 3 days. Mean illumination was 680 lux. Changes in ocular components and corneal curvature were measured. Refraction, eye length, and choroidal changes were dependent on the presence of blue light (P light, refraction did not change across frequencies (mean change -0.24 [diopters] D), while in the absence of blue light, we observed a hyperopic shift (>1 D) at high frequencies, and a myopic shift (>-0.6 D) at low frequencies. With blue light there was little difference in eye growth across frequencies (77 μm), while in the absence of blue light, eyes grew more at low temporal frequencies and less at high temporal frequencies (10 vs. 0.2 Hz: 145 μm; P light. Illuminants rich in blue light can protect against myopic eye growth when the eye is exposed to slow changes in luminance contrast as might occur with near work.

  10. Blue whales respond to anthropogenic noise.

    Directory of Open Access Journals (Sweden)

    Mariana L Melcón

    Full Text Available Anthropogenic noise may significantly impact exposed marine mammals. This work studied the vocalization response of endangered blue whales to anthropogenic noise sources in the mid-frequency range using passive acoustic monitoring in the Southern California Bight. Blue whales were less likely to produce calls when mid-frequency active sonar was present. This reduction was more pronounced when the sonar source was closer to the animal, at higher sound levels. The animals were equally likely to stop calling at any time of day, showing no diel pattern in their sensitivity to sonar. Conversely, the likelihood of whales emitting calls increased when ship sounds were nearby. Whales did not show a differential response to ship noise as a function of the time of the day either. These results demonstrate that anthropogenic noise, even at frequencies well above the blue whales' sound production range, has a strong probability of eliciting changes in vocal behavior. The long-term implications of disruption in call production to blue whale foraging and other behaviors are currently not well understood.

  11. Pectoral sound generation in the blue catfish Ictalurus furcatus.

    Science.gov (United States)

    Mohajer, Yasha; Ghahramani, Zachary; Fine, Michael L

    2015-03-01

    Catfishes produce pectoral stridulatory sounds by "jerk" movements that rub ridges on the dorsal process against the cleithrum. We recorded sound synchronized with high-speed video to investigate the hypothesis that blue catfish Ictalurus furcatus produce sounds by a slip-stick mechanism, previously described only in invertebrates. Blue catfish produce a variably paced series of sound pulses during abduction sweeps (pulsers) although some individuals (sliders) form longer duration sound units (slides) interspersed with pulses. Typical pulser sounds are evoked by short 1-2 ms movements with a rotation of 2°-3°. Jerks excite sounds that increase in amplitude after motion stops, suggesting constructive interference, which decays before the next jerk. Longer contact of the ridges produces a more steady-state sound in slides. Pulse pattern during stridulation is determined by pauses without movement: the spine moves during about 14 % of the abduction sweep in pulsers (~45 % in sliders) although movement appears continuous to the human eye. Spine rotation parameters do not predict pulse amplitude, but amplitude correlates with pause duration suggesting that force between the dorsal process and cleithrum increases with longer pauses. Sound production, stimulated by a series of rapid movements that set the pectoral girdle into resonance, is caused by a slip-stick mechanism.

  12. Blue-light emitting triazolopyridinium and triazoloquinolinium salts

    KAUST Repository

    Carboni, Valentina; Su, Xin; Qian, Hai; Aprahamian, Ivan; Credi, Alberto

    2017-01-01

    Compounds that emit blue light are of interest for applications that include optoelectronic devices and chemo/biosensing and imaging. The design and synthesis of small organic molecules that can act as high-efficiency deep-blue-light emitters

  13. Determinants of Colour Constancy and the Blue Bias

    Science.gov (United States)

    Gegenfurtner, Karl

    2017-01-01

    We investigated several sensory and cognitive determinants of colour constancy across 40 illumination hues. In the first experiment, we measured colour naming for the illumination and for the colour induced by the illumination on the colorimetric grey. Results confirmed that the induced colours are approximately complementary to the colour of the illumination. In the second experiment, we measured colour constancy using achromatic adjustments. Average colour constancy was perfect under the blue daylight illumination and decreased in colour directions away from the blue daylight illumination due to undershooting and a strong blue bias. Apart from this blue bias, colour constancy was not related to illumination discrimination and to chromatic detection measured previously with the same setup and stimuli. We also observed a strong negative relationship between the degree of colour constancy and the consensus of naming the illumination colour. Constancy coincided with a low naming consensus, in particular because bluish illumination colours were sometimes seen as achromatic. Blue bias and category consensus alone explained >68%, and all determinants together explained >94% of the variance of achromatic adjustments. These findings suggest that colour constancy is optimised for blue daylight. PMID:29348910

  14. Hypnosis-associated blue-tinted vision: a case report

    Directory of Open Access Journals (Sweden)

    Savedoff Aaron D

    2005-12-01

    Full Text Available Abstract Background Self-hypnosis has been taught routinely at the SUNY Upstate Medical University for treatment of pulmonary symptoms thought to be amenable to psychological therapy. While using hypnosis for relaxation, four individuals, including a patient with cystic fibrosis, reported development of blue-tinted vision. Based on a search of the literature, we believe this is the first published report of hypnosis-associated blue-tinted vision. Case presentation The patient reported blue-tinted vision when he used hypnosis on an almost daily basis for seven years. The visual change typically occurred when he was relaxed. Moreover, a concurrent erection in the absence of sexual thoughts usually was present. The other three individuals reported blue-tinted vision after learning how to use hypnosis for relaxation as part of a group hypnosis instruction. Conclusion The blue-tinted vision experienced by the individuals in this report may be the result of an hypnosis-induced primary change in cognitive processing. Additionally, as the relaxing effect of hypnosis can be associated with a reduction in blood pressure and increased blood flow, hypnosis-associated blue-tinted vision also may be related to retinal vasodilation.

  15. How does the blue-ringed octopus (Hapalochlaena lunulata) flash its blue rings?

    Science.gov (United States)

    Mäthger, Lydia M; Bell, George R R; Kuzirian, Alan M; Allen, Justine J; Hanlon, Roger T

    2012-11-01

    The blue-ringed octopus (Hapalochlaena lunulata), one of the world's most venomous animals, has long captivated and endangered a large audience: children playing at the beach, divers turning over rocks, and biologists researching neurotoxins. These small animals spend much of their time in hiding, showing effective camouflage patterns. When disturbed, the octopus will flash around 60 iridescent blue rings and, when strongly harassed, bite and deliver a neurotoxin that can kill a human. Here, we describe the flashing mechanism and optical properties of these rings. The rings contain physiologically inert multilayer reflectors, arranged to reflect blue-green light in a broad viewing direction. Dark pigmented chromatophores are found beneath and around each ring to enhance contrast. No chromatophores are above the ring; this is unusual for cephalopods, which typically use chromatophores to cover or spectrally modify iridescence. The fast flashes are achieved using muscles under direct neural control. The ring is hidden by contraction of muscles above the iridophores; relaxation of these muscles and contraction of muscles outside the ring expose the iridescence. This mechanism of producing iridescent signals has not previously been reported in cephalopods and we suggest that it is an exceptionally effective way to create a fast and conspicuous warning display.

  16. Blue objects in the vicinity of M13. 1

    International Nuclear Information System (INIS)

    Oganesyan, Eh.Ya.

    1978-01-01

    Presented are photometric data in the UBV system for 225 objects in the region of 16 square degrees in size, adjacent to M13 cluster. ''Two-colour diagram'' and ''colour-luminosity'' diagram are built, and on their basis analysis of the data obtained is made. Half the objects investigated are subdwarfs. Among others there are white - blue dwarfs conventional stars of the main sequence stars, halo stars, stars of globular clusters and objects, which might be of extragalactic nature. On the basis of object distribution as to brightness and colour, and also according to their visible distribution several different groups can be singled out. Several variable stars are also found as a result of photometric investigation

  17. The coherent variability of African river flows : composite climate ...

    African Journals Online (AJOL)

    The composite structure of the ocean and atmosphere around Africa is studied in the context of river flow variability. Annual streamflows are analysed for the Blue and White Nile, Congo, Niger, Senegal, Zambezi, and Orange Rivers, and inflow to Lake Malawi. Spectral energy is concentrated in 6.6- and 2.4-year bands.

  18. Non-destructive characterization of oriental porcelain glazes and blue underglaze pigments using μ-EDXRF, μ-Raman and VP-SEM

    Energy Technology Data Exchange (ETDEWEB)

    Coutinho, M.L. [Universidade Nova de Lisboa, REQUIMTE-CQFB, Faculdade de Ciencias e Tecnologia, Caparica (Portugal); Universidade Nova de Lisboa, Departamento de Conservacao e Restauro, Faculdade de Ciencias e Tecnologia, Caparica (Portugal); Muralha, V.S.F. [Universidade Nova de Lisboa, Research Unit VICARTE, Vidro e Ceramica para as Artes, Faculdade de Ciencias e Tecnologia, Caparica (Portugal); Mirao, J. [Universidade de Evora, Laboratorio HERCULES, Evora (Portugal); Veiga, J.P. [Universidade Nova de Lisboa, CENIMAT/I3N, Departamento de Ciencia dos Materiais, Faculdade de Ciencias e Tecnologia, Caparica (Portugal)

    2014-03-15

    The study of ancient materials with recognized cultural and economic value is a challenge to scientists and conservators, since it is usually necessary an approach through non-destructive techniques. Difficulties in establishing a correct analytical strategy are often significantly increased by the lack of knowledge on manufacture technologies and raw materials employed combined with the diversity of decay processes that may have acted during the lifetime of the cultural artefacts. A non-destructive characterization was performed on the glaze and underglaze pigments from a group of Chinese porcelain shards dated from the late Ming Dynasty (1368-1644) excavated at the Monastery of Santa Clara-a-Velha in Coimbra (Portugal). Chemical analysis was performed using micro-energy dispersive X-ray fluorescence spectrometry (μ-EDXRF). Mineralogical characterization was achieved by Raman microscopy (μ-Raman) and observation of small-surface crystallization dark spots with a metallic lustre in areas with high pigment concentration was done by variable pressure scanning electron microscopy (VP-SEM). Cobalt aluminate was identified as the blue underglaze pigment and a comparison of blue and dark blue pigments was performed by the ratio of Co, Mn, and Fe oxides, indicating a compositional difference between the two blue tonalities. Manganese oxide compounds were also identified as colouring agents in dark blue areas and surface migration of manganese compounds was verified. (orig.)

  19. Non-destructive characterization of oriental porcelain glazes and blue underglaze pigments using μ-EDXRF, μ-Raman and VP-SEM

    International Nuclear Information System (INIS)

    Coutinho, M.L.; Muralha, V.S.F.; Mirao, J.; Veiga, J.P.

    2014-01-01

    The study of ancient materials with recognized cultural and economic value is a challenge to scientists and conservators, since it is usually necessary an approach through non-destructive techniques. Difficulties in establishing a correct analytical strategy are often significantly increased by the lack of knowledge on manufacture technologies and raw materials employed combined with the diversity of decay processes that may have acted during the lifetime of the cultural artefacts. A non-destructive characterization was performed on the glaze and underglaze pigments from a group of Chinese porcelain shards dated from the late Ming Dynasty (1368-1644) excavated at the Monastery of Santa Clara-a-Velha in Coimbra (Portugal). Chemical analysis was performed using micro-energy dispersive X-ray fluorescence spectrometry (μ-EDXRF). Mineralogical characterization was achieved by Raman microscopy (μ-Raman) and observation of small-surface crystallization dark spots with a metallic lustre in areas with high pigment concentration was done by variable pressure scanning electron microscopy (VP-SEM). Cobalt aluminate was identified as the blue underglaze pigment and a comparison of blue and dark blue pigments was performed by the ratio of Co, Mn, and Fe oxides, indicating a compositional difference between the two blue tonalities. Manganese oxide compounds were also identified as colouring agents in dark blue areas and surface migration of manganese compounds was verified. (orig.)

  20. Non-destructive characterization of oriental porcelain glazes and blue underglaze pigments using μ-EDXRF, μ-Raman and VP-SEM

    Science.gov (United States)

    Coutinho, M. L.; Muralha, V. S. F.; Mirão, J.; Veiga, J. P.

    2014-03-01

    The study of ancient materials with recognized cultural and economic value is a challenge to scientists and conservators, since it is usually necessary an approach through non-destructive techniques. Difficulties in establishing a correct analytical strategy are often significantly increased by the lack of knowledge on manufacture technologies and raw materials employed combined with the diversity of decay processes that may have acted during the lifetime of the cultural artefacts. A non-destructive characterization was performed on the glaze and underglaze pigments from a group of Chinese porcelain shards dated from the late Ming Dynasty (1368-1644) excavated at the Monastery of Santa Clara- a- Velha in Coimbra (Portugal). Chemical analysis was performed using micro-energy dispersive X-ray fluorescence spectrometry (μ-EDXRF). Mineralogical characterization was achieved by Raman microscopy (μ-Raman) and observation of small-surface crystallization dark spots with a metallic lustre in areas with high pigment concentration was done by variable pressure scanning electron microscopy (VP-SEM). Cobalt aluminate was identified as the blue underglaze pigment and a comparison of blue and dark blue pigments was performed by the ratio of Co, Mn, and Fe oxides, indicating a compositional difference between the two blue tonalities. Manganese oxide compounds were also identified as colouring agents in dark blue areas and surface migration of manganese compounds was verified.

  1. Challenges for the next generation of BlueTEC emission technology; Anforderungen und Weiterentwicklungen zur naechsten Generation der BlueTEC-Antriebstechnologie

    Energy Technology Data Exchange (ETDEWEB)

    Enderle, C.; Binz, R.; Paule, M.; Mackensen, A.; Lindemann, B. [Daimler AG, Stuttgart (Germany)

    2010-07-01

    Mercedes-Benz BlueTEC vehicles have been on the cutting edge of clean diesel technology since 2006. BlueTEC vehicles furthermore passed millions of kilometres in the hands of customers without any problems. Of course SCR systems already meet the most stringent exhaust emissions standards in international markets such as the USA, Europe and Japan. Diesel engines with BlueTEC technology also reduce CO{sub 2} emissions and provide the high torque and performance associated with the diesel engine in addition to keeping exhaust emissions at the lowest possible level. The following challenges are the focus of efforts to further advance the BlueTEC drives: - Reduce development and calibration outlay. - Standardise and reduce the costs of SCR components. - Improve performance by further reducing exhaust emissions (e.g. SULEV) and meeting the special requirements associated with the ever lower exhaust temperatures of vehicles designed to minimise CO{sub 2} emissions. - Expand on BlueTEC technology by integrating additional emissions components and combining these with other CO{sub 2} technology modules such as hybrid systems. The BlueTEC diesel engines from Mercedes-Benz represents ultra-clean drive technology, with low CO{sub 2} emissions, that can be adapted for specific markets and vehicles in a modular fashion, ideally combined with other CO{sub 2} technologies, and refined to meet future requirements. (orig.)

  2. QCD on the BlueGene/L Supercomputer

    International Nuclear Information System (INIS)

    Bhanot, G.; Chen, D.; Gara, A.; Sexton, J.; Vranas, P.

    2005-01-01

    In June 2004 QCD was simulated for the first time at sustained speed exceeding 1 TeraFlops in the BlueGene/L supercomputer at the IBM T.J. Watson Research Lab. The implementation and performance of QCD in the BlueGene/L is presented

  3. QCD on the BlueGene/L Supercomputer

    Science.gov (United States)

    Bhanot, G.; Chen, D.; Gara, A.; Sexton, J.; Vranas, P.

    2005-03-01

    In June 2004 QCD was simulated for the first time at sustained speed exceeding 1 TeraFlops in the BlueGene/L supercomputer at the IBM T.J. Watson Research Lab. The implementation and performance of QCD in the BlueGene/L is presented.

  4. Blue-light emitting triazolopyridinium and triazoloquinolinium salts

    KAUST Repository

    Carboni, Valentina

    2017-01-27

    Compounds that emit blue light are of interest for applications that include optoelectronic devices and chemo/biosensing and imaging. The design and synthesis of small organic molecules that can act as high-efficiency deep-blue-light emitters in the solid state and can be easily processed from solutions represents a significant challenge. Herein we present the preparation and photophysical, photochemical and electrochemical properties of a series of triazolopyridinium and triazoloquinolinium compounds. The compounds are soluble in water or polar organic solvents and exhibit photoluminescence in the blue region of the spectrum in fluid solution, in the solid state and in a frozen matrix.

  5. Efficient fluorescent red, green, and blue organic light-emitting devices with a blue host of spirobifluorene derivative

    Energy Technology Data Exchange (ETDEWEB)

    Lee, R.-H. [Department of Chemical and Material Engineering, National Yunlin University of Science and Technology, Yunlin 640, Taiwan (China)], E-mail: lerongho@yuntech.edu.tw; Huang, Y.-W.; Wang, Y.-Y. [Department of Chemical and Material Engineering, National Yunlin University of Science and Technology, Yunlin 640, Taiwan (China); Chang, H.-Y. [EChem Hightech CO., LTD, Hsin-Chu Industrial Park, Hu-Kou, Hsin-Chu, Taiwan (China)

    2008-06-02

    Efficient fluorescent blue, green, and red (RGB) organic light-emitting devices (OLEDs) were fabricated using a blue host material of pyrimidine-containing spirobifluorene derivative 2,7-bis[2-(4-tert-butylphenyl)pyrimidine-5-yl]-9,9'-spirobifluorene (TBPSF) doped with blue dye perylene, green dye 10-(2-benzothiazolyl)-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H, 11H-benzo[l] pyrano[6,7,8-ij] quinolizin-11-one (C545T), and red dye 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl) -4H-pyran (DCJTB), respectively. The brightness and current efficiency of the perylene doped blue device reached 10117 cd/m{sup 2} and 2.97 cd/A. Green emission of the C545T doped device reached 8500 cd/m{sup 2} and 13.0 cd/A. Red emission of the DCJTB doped device can be as high as 9000 cd/m{sup 2} and 2.0 cd/A, respectively. High color purity of the blue (Commission Internationale de L'Eclairage (CIE{sub x,y}) coordinates (CIE, x = 0.27, y = 0.24)), green (CIE, x = 0.19, y = 0.63) and red (CIE, x = 0.62, y = 0.37) emissions were achieved for RGB dyes doped TBPSF OLEDs. High brightness, large current efficiency, and good color purity of TBPSF-based RGB OLEDs were obtained by the configuration optimization device, such as inserting the hole and electron-injection materials, and suitable dopant content and light emitting layer thickness.

  6. Blue Pseudoazulene-Skeleton Pigments of Natural Origin

    OpenAIRE

    井上, 謙一郎; イノウエ, ケンイチロウ; KENICHIRO, INOUE

    1993-01-01

    Genipin, an iridoid constituent of Genipa americana, readily reacts with amino acids in the presence of oxygen to give a mixture of polymeric blue pigments whose structures are not determined. In the basic studies to elucidate the structure and formation mechnism of blue pigments, the reaction of genipin with methylamine in the absence of oxygen yielded 9 red compounds leading to blue pigments. In this article, the structures and spectroscopic properties of these red compounds were described....

  7. Experimental investigation of the transverse modal instabilities onset in high power fully-aperiodic-large-pitch fiber lasers

    Science.gov (United States)

    Malleville, Marie-Alicia; Benoît, Aurélien; Dauliat, Romain; Leconte, Baptiste; Darwich, Dia; du Jeu, Rémi; Jamier, Raphaël.; Schwuchow, Anka; Schuster, Kay; Roy, Philippe

    2018-02-01

    Over the last decade, significant work has been carried out in order to increase the energy/peak power provided by fiber lasers. Indeed, new microstructured fibers with large (or very large) mode area cores (LMA) such as Distributed Mode Filtering (DMF) fibers and Large-Pitch Fibers (LPF) have been developed to address this concern. These technologies have allowed diffraction-limited emission with core diameters higher than 80 μm, and have state-of-the-art performances in terms of pulse energy or peak power while keeping an excellent spatial beam quality. Although these fibers were designed to reach high power levels while maintaining a single transverse mode propagation, power scaling becomes quickly limited by the onset of transverse modal instabilities (TMI). This effect suddenly arises when a certain average power threshold is exceeded, drastically degrading the emitted beam quality. In this work, we investigate the influence of the core dimensions and the refractive index mismatch between the active core and the background cladding material, on the TMI power threshold in rod-type Fully-Aperiodic-LPF. This fiber structure was specifically designed to enhance the higher-order modes (HOMs) delocalization out of the gain region and thus push further the onset of modal instabilities. Using a 400W pump diode at 976 nm, the power scaling, as well as the spatial beam quality and its temporal behavior were investigated in laser configuration, which theoretically provides a lower TMI power threshold than the amplifier one due to the lack of selective excitation of the fundamental mode.

  8. Quirks of dye nomenclature. 1. Evans blue.

    Science.gov (United States)

    Cooksey, C J

    2014-02-01

    The history, origin, identity, chemistry and use of Evans blue dye are described along with the first application to staining by Herbert McLean Evans in 1914. In the 1930s, the dye was marketed under the name, Evans blue dye, which was profoundly more acceptable than the ponderous chemical name.

  9. How bees distinguish patterns by green and blue modulation.

    Science.gov (United States)

    Horridge, Adrian

    2015-01-01

    In the 1920s, Mathilde Hertz found that trained bees discriminated between shapes or patterns of similar size by something related to total length of contrasting contours. This input is now interpreted as modulation in green and blue receptor channels as flying bees scan in the horizontal plane. Modulation is defined as total contrast irrespective of sign multiplied by length of edge displaying that contrast, projected to vertical, therefore, combining structure and contrast in a single input. Contrast is outside the eye; modulation is a phasic response in receptor pathways inside. In recent experiments, bees trained to distinguish color detected, located, and measured three independent inputs and the angles between them. They are the tonic response of the blue receptor pathway and modulation of small-field green or (less preferred) blue receptor pathways. Green and blue channels interacted intimately at a peripheral level. This study explores in more detail how various patterns are discriminated by these cues. The direction of contrast at a boundary was not detected. Instead, bees located and measured total modulation generated by horizontal scanning of contrasts, irrespective of pattern. They also located the positions of isolated vertical edges relative to other landmarks and distinguished the angular widths between vertical edges by green or blue modulation alone. The preferred inputs were the strongest green modulation signal and angular width between outside edges, irrespective of color. In the absence of green modulation, the remaining cue was a measure and location of blue modulation at edges. In the presence of green modulation, blue modulation was inhibited. Black/white patterns were distinguished by the same inputs in blue and green receptor channels. Left-right polarity and mirror images could be discriminated by retinotopic green modulation alone. Colors in areas bounded by strong green contrast were distinguished as more or less blue than the

  10. Global monthly water scarcity: Blue water footprints versus blue water availability

    NARCIS (Netherlands)

    Hoekstra, Arjen Ysbert; Mekonnen, Mesfin; Chapagain, Ashok; Mathews, R.E.; Richter, B.D.

    2012-01-01

    Freshwater scarcity is a growing concern, placing considerable importance on the accuracy of indicators used to characterize and map water scarcity worldwide. We improve upon past efforts by using estimates of blue water footprints (consumptive use of ground- and surface water flows) rather than

  11. THE RR LYRAE VARIABLES AND HORIZONTAL BRANCH OF NGC 6656 (M22) {sup ,}

    Energy Technology Data Exchange (ETDEWEB)

    Kunder, Andrea; Walker, Alistair R.; Paredes Alvarez, Leonardo [Cerro Tololo Inter-American Observatory, Casilla 603, La Serena (Chile); Stetson, Peter B. [Dominion Astrophysical Observatory, NRC-Herzberg, National Research Council, Victoria BC, V9E 2E7 (Canada); Cassisi, Santi [INAF-Osservatorio Astronomico di Collurania, Via M. Maggini, I-64100 Teramo (Italy); Layden, Andrew [Bowling Green State University, Bowling Green, OH 43403 (United States); Bono, Giuseppe [Dipartimento di Fisica, Universita di Roma Tor Vergata, Rome (Italy); Catelan, Márcio [Pontificia Universidad Católica de Chile, Departamento de Astronomía y Astrofísica, Av. Vicuña Mackenna 4860, 782-0436 Macul, Santiago (Chile); Clem, James L. [Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803-4001 (United States); Matsunaga, Noriyuki [Department of Astronomy, School of Science, The University of Tokyo (Japan); Salaris, Maurizio [Astrophysics Research Institute, Liverpool John Moores University, Twelve Quays House, Egerton Wharf, Birkenhead CH41 1LD (United Kingdom); Lee, Jae-Woo [Korea Astronomy and Space Science Institute, Daejeon 305-348 (Korea, Republic of); Chaboyer, Brian, E-mail: akunder@ctio.noao.edu, E-mail: mcatelan@astro.puc.cl [Department of Physics and Astronomy, Dartmouth College, Hanover, NH 03755 (United States)

    2013-11-01

    The first calibrated broadband UBVI time-series photometry is presented for the RR Lyrae variable stars in NGC 6656 (M22), with observations spanning a range of 22 years. We have also redetermined the variability types and periods for the RR Lyrae stars identified previously by photographic observations, revising the number of fundamental-mode RR Lyrae variables (RR0) to 10 and the number of first-overtone variables (RR1) to 16. The mean periods of the RR0 and RR1 variables are (P) {sub RR0} = 0.66 ± 0.02 days and (P) {sub RR1} = 0.33 ± 0.01 days, respectively, supporting an Oosterhoff II classification for the cluster. The number ratio of RR1-type to all RR-type variables is N {sub 1}/N{sub RR} = 0.61, also consistent with an Oosterhoff II designation. Both the RR Lyrae stars' minimum light colors and the blue edge of the RR Lyrae instability strip suggest E( B – – V) = 0.36 ± 0.02 mag toward M22. Regarding the HB morphology of M22, we find (B-R)/(B+V+R) = +0.97 ± 0.1 and at least one ''gap'' located in an unusual part of the blue HB, in the middle of the so-called hot HB stars.

  12. The ancient blue oak woodlands of California: longevity and hydroclimatic history

    Science.gov (United States)

    Stahle, D.W.; Griffin, R.D.; Meko, D.M.; Therrell, M.D.; Edmondson, J.R.; Cleaveland, M.K.; Burnette, D.J.; Abatzoglou, J.T.; Redmond, K.T.; Dettinger, M.D.; Cayan, D.R.

    2013-01-01

    Ancient blue oak trees are still widespread across the foothills of the Coast Ranges, Cascades, and Sierra Nevada in California. The most extensive tracts of intact old-growth blue oak woodland appear to survive on rugged and remote terrain in the south Coast Ranges and on the foothills west and southwest of Mt. Lassen. In our sampling of old-growth stands, most blue oak appear to have recruited to the canopy in the mid- to late-19th century. The oldest living blue oak tree sampled was over 459-years old and several dead blue oak logs had over 500 annual rings. Precipitation sensitive tree-ring chronologies up to 700-years long have been developed from old blue oak trees and logs. Annual ring-width chronologies of blue oak are strongly correlated with cool season precipitation totals, streamflow in the major rivers of California, and the estuarine water quality of San Francisco Bay. A new network of 36 blue oak chronologies records spatial anomalies in growth that arise from latitudinal changes in the mean storm track and location of landfalling atmospheric rivers. These long, climate-sensitive blue oak chronologies have been used to reconstruct hydroclimatic history in California and will help to better understand and manage water resources. The environmental history embedded in blue oak growth chronologies may help justify efforts to conserve these authentic old-growth native woodlands.

  13. Suppressed speckle contrast of blue light emission out of white lamp with phosphors excited by blue laser diodes for high-brightness lighting applications

    Science.gov (United States)

    Kinoshita, Junichi; Ikeda, Yoshihisa; Takeda, Yuji; Ueno, Misaki; Kawasaki, Yoji; Matsuba, Yoshiaki; Heike, Atsushi

    2012-11-01

    The speckle contrast of blue light emission out of high-brightness white lamps using phosphors excited by InGaN/GaN blue laser diodes is evaluated as a measure of coherence. As a result, speckle contrast of as low as 1.7%, the same level as a blue light emitting diode, is obtained. This implies that the original blue laser light can be converted into incoherent light through lamp structures without any dynamic mechanisms. This unique speckle-free performance is considered to be realized by multiple scattering inside the lamp structure, the multi-longitudinal mode operation of the blue laser diodes, and the use of multiple laser diodes. Such almost-incoherent white lamps can be applied for general lighting without any nuisance of speckle noise and should be categorized as lamps rather than lasers in terms of laser safety regulation.

  14. Effects of competition on great and blue tit reproduction: intensity and importance in relation to habitat quality.

    Science.gov (United States)

    Dhondt, André A

    2010-01-01

    1. In studies on the effect of competition in plant communities two terms are used to describe its effects: the absolute reduction in growth of an individual as a consequence of the presence of another one is called intensity, while the relative impact of competition on an individual as a proportion of the impact of the whole environment is called importance. One school of thought is that the role of competition remains constant across productivity gradients, while the other is that it decreases with increasing severity. J.B. Grace (1991. A clarification of the debate between grime and tilman. Functional Ecology, 5, 583-587.) suggested that the apparent contradiction might be solved if we acknowledge that the two schools are discussing different aspects of competition: the intensity of competition might remain constant while its importance declines with increasing severity. 2. There are no studies that compare intensity and importance of competition in bird populations between areas that differ in quality or productivity and hence it is not possible to make predictions how intensity or importance of competition would vary between them. 3. I compared variation in intensity and importance of competition of three demographic variables between five plots that differ strongly in quality for great Parus major L. and blue tit Cyanistes caeruleus (L.). 4. Both intensity and importance of competition are larger in great than in blue tit populations meaning that the effect of competition on demographic variables is stronger in great than in blue tits and that the contribution of competition to variation in these variables is relatively higher in great than in blue tits. 5. Intensity of competition is higher in low quality than in high quality plots for both species, a result not expected from studies in plant communities. 6. Importance of competition varies strongly between plots. It is larger in oak-dominated plots than in mixed deciduous plots. 7. In birds breeding density

  15. A binary origin for 'blue stragglers' in globular clusters.

    Science.gov (United States)

    Knigge, Christian; Leigh, Nathan; Sills, Alison

    2009-01-15

    Blue stragglers in globular clusters are abnormally massive stars that should have evolved off the stellar main sequence long ago. There are two known processes that can create these objects: direct stellar collisions and binary evolution. However, the relative importance of these processes has remained unclear. In particular, the total number of blue stragglers found in a given cluster does not seem to correlate with the predicted collision rate, providing indirect support for the binary-evolution model. Yet the radial distributions of blue stragglers in many clusters are bimodal, with a dominant central peak: this has been interpreted as an indication that collisions do dominate blue straggler production, at least in the high-density cluster cores. Here we report that there is a clear, but sublinear, correlation between the number of blue stragglers found in a cluster core and the total stellar mass contained within it. From this we conclude that most blue stragglers, even those found in cluster cores, come from binary systems. The parent binaries, however, may themselves have been affected by dynamical encounters. This may be the key to reconciling all of the seemingly conflicting results found to date.

  16. Screening of oral premalignant lesions in smokers using toluidine blue

    Directory of Open Access Journals (Sweden)

    Yanti Leosari

    2009-06-01

    Full Text Available Background: A smoker is associated with the risk of developing oral premalignant lesions due to the cacinogenic contents in cigarette. Toluidine blue is a basic chromatic dye used in screening the presence of premalignant lesions due to its ability to detect acidic components in cells and tissues. Purpose: This study was purposed to observe the outcomes of toluidine blue staining on oral mucosa of smokers and non smokers and to find out whether quantity and duration of smoking affect the final results of toluidine blue staining. Methods: Forty male subjects, aged 20-60 years old were involved in this study, consisted of 10 heavy smokers, 10 moderate smokers, 10 light smokers and 10 non smokers. Subjects were instructed to rinse their mouths with mineral water for 20 seconds followed by acetic acid 1% for another 20 seconds. Toluidine blue stain was applied in excess and left on site for 1 minute. Subjects were instructed to rinse with acetic acid 1% and sufficient water consecutively for 20 seconds each. The areas of oral mucosa that stained blue were captured with intraoral camera and transferred to the computer unit. The staining procedure was repeated after 14 days. Results: Chi-square test showed that toluidine blue positive staining dominates the smokers group. Regression and correlation test indicate that Toluidine blue staining is more obvious in subjects who consume more cigarettes. Conclusion: It was concluded that oral mucosa of smokers absorbed more toluidine blue than that of non smokers and retention of toluidine blue is affected by quantity and duration of smoking.

  17. Origin of faint blue stars

    International Nuclear Information System (INIS)

    Tutukov, A.; Iungelson, L.

    1987-01-01

    The origin of field faint blue stars that are placed in the HR diagram to the left of the main sequence is discussed. These include degenerate dwarfs and O and B subdwarfs. Degenerate dwarfs belong to two main populations with helium and carbon-oxygen cores. The majority of the hot subdwarfs most possibly are helium nondegenerate stars that are produced by mass exchange close binaries of moderate mass cores (3-15 solar masses). The theoretical estimates of the numbers of faint blue stars of different types brighter than certain stellar magnitudes agree with star counts based on the Palomar Green Survey. 28 references

  18. Blue light phototherapy for Psoriasis from a systems biology perspective

    NARCIS (Netherlands)

    Félix Garza, Z.C.; Liebmann, J.; Hilbers, P.A.J.; Riel, van N.A.W.

    2014-01-01

    This work analyses the effect of UV-free blue light (BL) irradiation of the skin using mathematical modelling. Prior research has shown that blue light reduces the proliferation of keratinocytes by inducing their differentiation, and causes apoptosis of lymphocytes. The effects of blue light on

  19. The blue supergiant MN18 and its bipolar circumstellar nebula

    Science.gov (United States)

    Gvaramadze, V. V.; Kniazev, A. Y.; Bestenlehner, J. M.; Bodensteiner, J.; Langer, N.; Greiner, J.; Grebel, E. K.; Berdnikov, L. N.; Beletsky, Y.

    2015-11-01

    We report the results of spectrophotometric observations of the massive star MN18 revealed via discovery of a bipolar nebula around it with the Spitzer Space Telescope. Using the optical spectrum obtained with the Southern African Large Telescope, we classify this star as B1 Ia. The evolved status of MN18 is supported by the detection of nitrogen overabundance in the nebula, which implies that it is composed of processed material ejected by the star. We analysed the spectrum of MN18 by using the code CMFGEN, obtaining a stellar effective temperature of ≈21 kK. The star is highly reddened, E(B - V) ≈ 2 mag. Adopting an absolute visual magnitude of MV = -6.8 ± 0.5 (typical of B1 supergiants), MN18 has a luminosity of log L/L⊙ ≈ 5.42 ± 0.30, a mass-loss rate of ≈(2.8-4.5) × 10- 7 M⊙ yr- 1, and resides at a distance of ≈5.6^{+1.5} _{-1.2} kpc. We discuss the origin of the nebula around MN18 and compare it with similar nebulae produced by other blue supergiants in the Galaxy (Sher 25, HD 168625, [SBW2007] 1) and the Large Magellanic Cloud (Sk-69°202). The nitrogen abundances in these nebulae imply that blue supergiants can produce them from the main-sequence stage up to the pre-supernova stage. We also present a K-band spectrum of the candidate luminous blue variable MN56 (encircled by a ring-like nebula) and report the discovery of an OB star at ≈17 arcsec from MN18. The possible membership of MN18 and the OB star of the star cluster Lynga 3 is discussed.

  20. Blue-noise remeshing with farthest point optimization

    KAUST Repository

    Yan, Dongming

    2014-08-01

    In this paper, we present a novel method for surface sampling and remeshing with good blue-noise properties. Our approach is based on the farthest point optimization (FPO), a relaxation technique that generates high quality blue-noise point sets in 2D. We propose two important generalizations of the original FPO framework: adaptive sampling and sampling on surfaces. A simple and efficient algorithm for accelerating the FPO framework is also proposed. Experimental results show that the generalized FPO generates point sets with excellent blue-noise properties for adaptive and surface sampling. Furthermore, we demonstrate that our remeshing quality is superior to the current state-of-the art approaches. © 2014 The Eurographics Association and John Wiley & Sons Ltd.

  1. Blue-noise remeshing with farthest point optimization

    KAUST Repository

    Yan, Dongming; Guo, Jianwei; Jia, Xiaohong; Zhang, Xiaopeng; Wonka, Peter

    2014-01-01

    In this paper, we present a novel method for surface sampling and remeshing with good blue-noise properties. Our approach is based on the farthest point optimization (FPO), a relaxation technique that generates high quality blue-noise point sets in 2D. We propose two important generalizations of the original FPO framework: adaptive sampling and sampling on surfaces. A simple and efficient algorithm for accelerating the FPO framework is also proposed. Experimental results show that the generalized FPO generates point sets with excellent blue-noise properties for adaptive and surface sampling. Furthermore, we demonstrate that our remeshing quality is superior to the current state-of-the art approaches. © 2014 The Eurographics Association and John Wiley & Sons Ltd.

  2. THE PITFALLS OF THE BLUE OCEAN STRATEGY CANVAS

    DEFF Research Database (Denmark)

    Lindgren, Peter; Saghaug, Kristin Margrethe; Clemmensen, Suberia

    2009-01-01

    Numerous authors have developed a list of tactics and analyticaltechniques to discover new business or new business models (Markides2008)(Johnson 2008). The Blue Ocean strategy (Kim & Mauborgne 2005)have been one of these - probably one of the most important analyticaltechniques related to the area...... of innovation and new business model (BM)innovation since 2005. Today many consultancies and managersresponsible for innovation use the Blue Ocean framework as one of theirtop 5 innovation tools.Wanting to accentuate the importance of analyzing the strategy canvascarefully, when generating new business models...... - it is important tounderstand the very foundation and construction of the strategy canvas -namely value.This paper addresses the question on How is value defined, measured andfrom which viewed in the Blue Ocean theory and framework. How is valuedefined and used by companies using the Blue Ocean strategy...

  3. Variability of the Structural Coloration in Two Butterfly Species with Different Prezygotic Mating Strategies.

    Directory of Open Access Journals (Sweden)

    Gábor Piszter

    Full Text Available Structural coloration variability was investigated in two Blue butterfly species that are common in Hungary. The males of Polyommatus icarus (Common Blue and Plebejus argus (Silver-studded Blue use their blue wing coloration for conspecific recognition. Despite living in the same type of habitat, these two species display differences in prezygotic mating strategy: the males of P. icarus are patrolling, while P. argus males have sedentary behavior. Therefore, the species-specific photonic nanoarchitecture, which is the source of the structural coloration, may have been subjected to different evolutionary effects. Despite the increasing interest in photonic nanoarchitectures of biological origin, there is a lack of studies focused on the biological variability of structural coloration that examine a statistically relevant number of individuals from the same species. To investigate possible structural color variation within the same species in populations separated by large geographical distances, climatic differences, or applied experimental conditions, one has to be able to compare these variations to the normal biological variability within a single population. The structural coloration of the four wings of 25 male individuals (100 samples for each species was measured and compared using different light-collecting setups: perpendicular and with an integrating sphere. Significant differences were found in the near UV wavelength region that are perceptible by these polyommatine butterflies but are invisible to human observers. The differences are attributed to the differences in the photonic nanoarchitecture in the scales of these butterflies. Differences in the intensity of structural coloration were also observed and were tentatively attributed to the different prezygotic mating strategies of these insects. Despite the optical complexity of the scale covered butterfly wings, for sufficiently large sample batches, the averaged normal incidence

  4. Variability of the Structural Coloration in Two Butterfly Species with Different Prezygotic Mating Strategies.

    Science.gov (United States)

    Piszter, Gábor; Kertész, Krisztián; Bálint, Zsolt; Biró, László Péter

    2016-01-01

    Structural coloration variability was investigated in two Blue butterfly species that are common in Hungary. The males of Polyommatus icarus (Common Blue) and Plebejus argus (Silver-studded Blue) use their blue wing coloration for conspecific recognition. Despite living in the same type of habitat, these two species display differences in prezygotic mating strategy: the males of P. icarus are patrolling, while P. argus males have sedentary behavior. Therefore, the species-specific photonic nanoarchitecture, which is the source of the structural coloration, may have been subjected to different evolutionary effects. Despite the increasing interest in photonic nanoarchitectures of biological origin, there is a lack of studies focused on the biological variability of structural coloration that examine a statistically relevant number of individuals from the same species. To investigate possible structural color variation within the same species in populations separated by large geographical distances, climatic differences, or applied experimental conditions, one has to be able to compare these variations to the normal biological variability within a single population. The structural coloration of the four wings of 25 male individuals (100 samples for each species) was measured and compared using different light-collecting setups: perpendicular and with an integrating sphere. Significant differences were found in the near UV wavelength region that are perceptible by these polyommatine butterflies but are invisible to human observers. The differences are attributed to the differences in the photonic nanoarchitecture in the scales of these butterflies. Differences in the intensity of structural coloration were also observed and were tentatively attributed to the different prezygotic mating strategies of these insects. Despite the optical complexity of the scale covered butterfly wings, for sufficiently large sample batches, the averaged normal incidence measurements and

  5. Blue jay attacks and consumes cedar waxwing

    Science.gov (United States)

    Daniel Saenz; Joshua B. Pierce

    2009-01-01

    Blue Jays (Cyanocitta cristata) are known to be common predators on bird nests (Wilcove 1985, Picman and Schriml 1994). In addition to predation on eggs and nestlings, Blue Jays occasionally prey on fledgling and adult birds (Johnson and Johnson 1976, Dubowy 1985). A majority of reports involve predation on House Sparrows (Passer domesticus) and other small birds (...

  6. BlueHealth: a study programme protocol for mapping and quantifying the potential benefits to public health and well-being from Europe's blue spaces.

    Science.gov (United States)

    Grellier, James; White, Mathew P; Albin, Maria; Bell, Simon; Elliott, Lewis R; Gascón, Mireia; Gualdi, Silvio; Mancini, Laura; Nieuwenhuijsen, Mark J; Sarigiannis, Denis A; van den Bosch, Matilda; Wolf, Tanja; Wuijts, Susanne; Fleming, Lora E

    2017-06-14

    Proximity and access to water have long been central to human culture and accordingly deliver countless societal benefits. Over 200 million people live on Europe's coastline, and aquatic environments are the top recreational destination in the region. In terms of public health, interactions with 'blue space' (eg, coasts, rivers, lakes) are often considered solely in terms of risk (eg, drowning, microbial pollution). Exposure to blue space can, however, promote health and well-being and prevent disease, although underlying mechanisms are poorly understood. The BlueHealth project aims to understand the relationships between exposure to blue space and health and well-being, to map and quantify the public health impacts of changes to both natural blue spaces and associated urban infrastructure in Europe, and to provide evidence-based information to policymakers on how to maximise health benefits associated with interventions in and around aquatic environments. To achieve these aims, an evidence base will be created through systematic reviews, analyses of secondary data sets and analyses of new data collected through a bespoke international survey and a wide range of community-level interventions. We will also explore how to deliver the benefits associated with blue spaces to those without direct access through the use of virtual reality. Scenarios will be developed that allow the evaluation of health impacts in plausible future societal contexts and changing environments. BlueHealth will develop key inputs into policymaking and land/water-use planning towards more salutogenic and sustainable uses of blue space, particularly in urban areas. Throughout the BlueHealth project, ethics review and approval are obtained for all relevant aspects of the study by the local ethics committees prior to any work being initiated and an ethics expert has been appointed to the project advisory board. So far, ethical approval has been obtained for the BlueHealth International Survey and

  7. Northeast Atlantic blue whiting

    OpenAIRE

    Heino, Mikko

    2010-01-01

    Heino, M. 2010. Northeast Atlantic blue whiting. In Life cycle spatial patterns of small pelagic fish in the Northeast Atlantic, pp. 59-64. Ed by P. Petitgas. ICES Cooperative Research Report 306. ICES, Copenhagen.

  8. Manajemen Strategi Pengembangan Pariwisata dengan Pendekatan Blue Ocean Strategy

    OpenAIRE

    Muzha, Vianda Kushardianti

    2015-01-01

    Persaingan industri pariwisata di Indonesia saat ini sangatlah ketat, setiap daerah berlomba untuk menonjolkan keunikannya tersendiri. Dengan adanya persaingan yang sangat ketat tersebut, Kota Batu berusaha keluar dari persaingan (red ocean) dengan menciptkan inovasi baru melalui konsep Blue Ocean Strategy. Blue Ocean Strategy adalah istilah dalam ilmu manajemen strategi yang merujuk pada siasat untuk menciptakan pasar baru yang belum dipenuhi persaingan yang ketat. Blue Ocean Strategy pada d...

  9. Plant responses to UV and blue light: biochemical and genetic approaches

    International Nuclear Information System (INIS)

    Jenkins, G.I.; Christie, J.M.; Fuglevand, G.; Long, J.C.; Jackson, J.A.

    1995-01-01

    UV and blue light control many aspects of plant growth and development. It is evident that several different photoreceptors mediate responses to UV and blue light, and there are reports of the functional and biochemical characterisation of a putative photoreceptor for phototropism and of the functional and molecular characterisation of the CRY1 photoreceptor, encoded by the Arabidopsis HY4 gene. The CRY1 photoreceptor mediates extension growth and gene expression responses to UV-A/blue light presumably through different or branching signal transduction pathways. Progress has been made in cell physiological and biochemical studies of UV/blue light signal transduction, but much remains to be done to relate candidate UV/blue signal transduction events to particular photoreceptors and responses. The application of a genetic approach in Arabidopsis has been responsible for many advances in understanding UV/blue responses, but further UV-B, UV-A and blue light response mutants need to be isolated. (author)

  10. BlueHealth: a study programme protocol for mapping and quantifying the potential benefits to public health and well-being from Europe’s blue spaces

    Science.gov (United States)

    White, Mathew P; Albin, Maria; Bell, Simon; Elliott, Lewis R; Gascón, Mireia; Gualdi, Silvio; Mancini, Laura; Nieuwenhuijsen, Mark J; Sarigiannis, Denis A; van den Bosch, Matilda; Wolf, Tanja; Wuijts, Susanne; Fleming, Lora E

    2017-01-01

    Introduction Proximity and access to water have long been central to human culture and accordingly deliver countless societal benefits. Over 200 million people live on Europe’s coastline, and aquatic environments are the top recreational destination in the region. In terms of public health, interactions with ‘blue space’ (eg, coasts, rivers, lakes) are often considered solely in terms of risk (eg, drowning, microbial pollution). Exposure to blue space can, however, promote health and well-being and prevent disease, although underlying mechanisms are poorly understood. Aims and methods The BlueHealth project aims to understand the relationships between exposure to blue space and health and well-being, to map and quantify the public health impacts of changes to both natural blue spaces and associated urban infrastructure in Europe, and to provide evidence-based information to policymakers on how to maximise health benefits associated with interventions in and around aquatic environments. To achieve these aims, an evidence base will be created through systematic reviews, analyses of secondary data sets and analyses of new data collected through a bespoke international survey and a wide range of community-level interventions. We will also explore how to deliver the benefits associated with blue spaces to those without direct access through the use of virtual reality. Scenarios will be developed that allow the evaluation of health impacts in plausible future societal contexts and changing environments. BlueHealth will develop key inputs into policymaking and land/water-use planning towards more salutogenic and sustainable uses of blue space, particularly in urban areas. Ethics and dissemination Throughout the BlueHealth project, ethics review and approval are obtained for all relevant aspects of the study by the local ethics committees prior to any work being initiated and an ethics expert has been appointed to the project advisory board. So far, ethical approval

  11. The Blue Hook Populations of Massive Globular Clusters

    Science.gov (United States)

    Brown, Thomas

    2006-07-01

    Blue hook stars are a class of hot { 35,000 K} subluminous horizontal branch stars that have been recently discovered using HST ultraviolet images of the globular clusters omega Cen and NGC 2808. These stars occupy a region of the HR diagram that is unexplained by canonical stellar evolution theory. Using new theoretical evolutionary and atmospheric models, we have shown that the blue hook stars are very likely the progeny of stars that undergo extensive internal mixing during a late helium core flash on the white dwarf cooling curve. This "flash mixing" produces an enormous enhancement of the surface helium and carbon abundances, which suppresses the flux in the far ultraviolet. Although flash mixing is more likely to occur in stars that are born with high helium abundances, a high helium abundance, by itself, does not explain the presence of a blue hook population - flash mixing of the envelope is required. We propose ACS ultraviolet {SBC/F150LP and HRC/F250W} observations of the five additional globular clusters for which the presence of blue hook stars is suspected from longer wavelength observations. Like omega Cen and NGC 2808, these five targets are also among the most massive globular clusters, because less massive clusters show no evidence for blue hook stars. Because our targets span 1.5 dex in metallicity, we will be able to test our prediction that flash-mixing should be less drastic in metal-rich blue hook stars. In addition, our observations will test the hypothesis that blue hook stars only form in globular clusters massive enough to retain the helium-enriched ejecta from the first stellar generation. If this hypothesis is correct, then our observations will yield important constraints on the chemical evolution and early formation history in globular clusters, as well as the role of helium self-enrichment in producing blue horizontal branch morphologies and multiple main sequence turnoffs. Finally, our observations will provide new insight into the

  12. Influence of vegetation dynamic modeling on the allocation of green and blue waters

    Science.gov (United States)

    Ruiz-Pérez, Guiomar; Francés, Félix

    2015-04-01

    The long history of the Mediterranean region is dominated by the interactions and co-evolution between man and its natural environment. It is important to consider that the Mediterranean region is recurrently or permanently confronted with the scarcity of the water. The issue of climate change is (and will be) aggravating this situation. This raises the question of a loss of services that ecosystems provide to human and also the amount of available water to be used by vegetation. The question of the water cycle, therefore, should be considered in an integrated manner by taking into account both blue water (water in liquid form used for the human needs or which flows into the oceans) and green water (water having the vapor for resulting from evaporation and transpiration processes). In spite of this, traditionally, very few hydrological models have incorporated the vegetation dynamic as a state variable. In fact, most of them are able to represent fairly well the observed discharge, but usually including the vegetation as a static parameter. However, in the last decade, the number of hydrological models which explicitly take into account the vegetation development as a state variable has increased substantially. In this work, we want to analyze if it is really necessary to use a dynamic vegetation model to quantify adequately the distribution of water into blue and green water. The study site is located in the Public Forest Monte de la Hunde y Palomeras (Spain). The vegetation in the study area is dominated by Aleppo pine of high tree density with scant presence of other species. Two different daily models were applied (with static and dynamic vegetation representation respectively) in three different scenarios: dry year (2005), normal year (2008) and wet year (2010). The static vegetation model simulates the evapotranspiration considering the vegetation as a stationary parameter. Contrarily, the dynamic vegetation model connects the hydrological model with a

  13. Effects of watershed land use and geomorphology on stream low flows during severe drought conditions in the southern Blue Ridge Mountains, Georgia and North Carolina, United States

    Science.gov (United States)

    Katie Price; C. Jackson; Albert Parker; Trond Reitan; John Dowd; Mike Cyterski

    2011-01-01

    Land use and physiographic variability influence stream low flows, yet their interactions and relative influence remain unresolved. Our objective was to assess the influence of land use and watershed geomorphic characteristics on low-flow variability in the southern Blue Ridge Mountains of North Carolina and Georgia. Ten minute interval discharge data for 35 streams (...

  14. PENGARUH BRAND IMAGE DAN KUALITAS PELAYANAN TERHADAP KEPUASAN WISATAWAN DALAM MEMILIH TAKSI BLUE BIRD DI BALI

    Directory of Open Access Journals (Sweden)

    Dewa Ayu Putu Mega Puriani

    2017-07-01

    Full Text Available In Bali, many types of taxi can be encountered starting from the airport until city and tourist destination, one of them is Blue Bird Taxi. Blue Bird taxi has a brand image and good service quality which can be seen from many awards, some of them are Mark Plus Wow Service Excellence Award 2015 and Indonesian Leading Taxi/Limousine Company. Along with the technology development, giving significant impact to competition among land transportation for instance online based taxi. The technique of determining the respondents is purposive sampling technique with the number of respondents were 170 respondents. Furthermore, in analysing the data, this study using multiple regression analysis techniques. Results of this study mention that variable dimension dominate on brand image is strength. In partially brand image give positive and significant impact on tourist satisfaction with tcount of 2,465 and significant value of 0,015. And variable dimension dominate on service quality is tangible. Service quality give positive and significant impact on tourist satisfaction with tcount of 9,219 and significant value of 0,000. Simultaneously, it can be concluded that brand image and service quality give positive and significant impact on tourist satisfaction with Fcount of 105,731 and significant value of 0,000.

  15. A prospective randomized trial comparing patent blue and methylene blue for the detection of the sentinel lymph node in breast cancer patients

    Directory of Open Access Journals (Sweden)

    Régis Resende Paulinelli

    Full Text Available Summary Introduction: Methylene blue is more widely available and less expensive than patent blue, with an apparently lower risk of anaphylaxis. Objective: The two dyes were compared regarding detection of the sentinel lymph node (SLN. Method: A prospective, randomized trial involved 142 patients with invasive breast carcinoma. Sixty-nine (49.3% assigned to patent blue (group A and 71 (50.70% to methylene blue (group B. Thirty-five patients (25.0% were clinical stage III or IV; 55 (38.7% had axillary lymph nodes affected; and 69 (49.3% underwent neoadjuvant chemotherapy. Two patients were excluded because the dye type was not recorded. Results: Patients and tumor characteristics were similar in both groups. SLNs were identified in 47 women (68.1% in group A and 43 (60.6% in group B (p=0.35. SLNs were affected in 22 cases (51.2% in group A and 21 (48.8% in group B (p=0.62. The SLN was the only node affected in 12 cases (54.5% in group A and six (33.3% in group B (p=0.18. The time and degree of difficulty involved in identifying the SLN were similar in both groups. There were no complications or allergies. Conclusion: Methylene blue performed as well as patent blue in identifying the SLN in breast cancer patients.

  16. Blue light-mediated inactivation of Enterococcus faecalis in vitro.

    Science.gov (United States)

    Pileggi, Giorgio; Wataha, John C; Girard, Myriam; Grad, Iwona; Schrenzel, Jacques; Lange, Norbert; Bouillaguet, Serge

    2013-05-01

    In dentistry, residual infection remains a major cause of failure after endodontic treatment; many of these infections involve Enterococcus faecalis. In the current study, we explored the possibility that blue light activated photosensitizers could be used, in principle, to inactivate this microbe as an adjunct disinfection strategy for endodontic therapy. Three blue light absorbing photosensitizers, eosin-Y, rose bengal, and curcumin, were tested on E. faecalis grown in planktonic suspensions or biofilms. Photosensitizers were incubated for 30 min with bacteria then exposed to blue light (450-500 nm) for 240 s. Sodium hypochlorite (3%) was used as a control. After 48 h, the viability of E. faecalis was estimated by measuring colony-forming units post-exposure vs. untreated controls (CFU/mL). Blue light irradiation alone did not alter E. faecalis viability. For planktonic cultures, blue light activated eosin-Y (5 μM), rose bengal (1 μM), or curcumin (5 μM) significantly (pcurcumin of 100, 10, and 10 μM respectively, completely suppressed E. faecalis viability (p<0.05). Although the current results are limited to an in vitro model, they support further exploration of blue light activated antimicrobials as an adjunct therapy in endodontic treatment. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. Blue Ribbon Panel Report

    Science.gov (United States)

    An NCI Cancer Currents blog by the NCI acting director thanking the cancer community for contributing to the Cancer Moonshot Blue Ribbon Panel report, which was presented to the National Cancer Advisory Board on September 7.

  18. Twisted bilayer blue phosphorene: A direct band gap semiconductor

    Science.gov (United States)

    Ospina, D. A.; Duque, C. A.; Correa, J. D.; Suárez Morell, Eric

    2016-09-01

    We report that two rotated layers of blue phosphorene behave as a direct band gap semiconductor. The optical spectrum shows absorption peaks in the visible region of the spectrum and in addition the energy of these peaks can be tuned with the rotational angle. These findings makes twisted bilayer blue phosphorene a strong candidate as a solar cell or photodetection device. Our results are based on ab initio calculations of several rotated blue phosphorene layers.

  19. Fluctuating and Directional Asymmetry of the Blue Mussel (

    NARCIS (Netherlands)

    Lajus, D.; Katolikova, M.; Strelkov, P.; Hummel, H.

    2015-01-01

    In this work we examined morphological variation at different levels to study performance and population structuring of the blue mussel Mytilus edulis. Our objectives were: (i) to develop an integrated technique for analyzing morphological variation in blue mussels and, based on this technique; (ii)

  20. The Blue Marble

    Science.gov (United States)

    2002-01-01

    This spectacular Moderate Resolution Imaging Spectroradiometer (MODIS) 'blue marble' image is based on the most detailed collection of true-color imagery of the entire Earth to date. Using a collection of satellite-based observations, scientists and visualizers stitched together months of observations of the land surface, oceans, sea ice, and clouds into a seamless, true-color mosaic of every square kilometer (.386 square mile) of our planet. Most of the information contained in this image came from MODIS, illustrating MODIS' outstanding capacity to act as an integrated tool for observing a variety of terrestrial, oceanic, and atmospheric features of the Earth. The land and coastal ocean portions of this image is based on surface observations collected from June through September 2001 and combined, or composited, every eight days to compensate for clouds that might block the satellite's view on any single day. Global ocean color (or chlorophyll) data was used to simulate the ocean surface. MODIS doesn't measure 3-D features of the Earth, so the surface observations were draped over topographic data provided by the U.S. Geological Survey EROS Data Center. MODIS observations of polar sea ice were combined with observations of Antarctica made by the National Oceanic and Atmospheric Administration's AVHRR sensor-the Advanced Very High Resolution Radiometer. The cloud image is a composite of two days of MODIS imagery collected in visible light wavelengths and a third day of thermal infra-red imagery over the poles. A large collection of imagery based on the blue marble in a variety of sizes and formats, including animations and the full (1 km) resolution imagery, is available at the Blue Marble page. Image by Reto Stockli, Render by Robert Simmon. Based on data from the MODIS Science Team

  1. Borax methylene blue: a spectroscopic and staining study.

    Science.gov (United States)

    Donaldson, P T; Russo, A; Reynolds, C; Lillie, R D

    1978-07-01

    Borax methylene blue is quite stable at room temperatures of 22-25 C. At 30 C polychroming is slow; during 50 days in a water bath at this temperature the absorption peak moves from 665 to 656 nm. At 35 C, the absorption peak reaches 660 nm in 7 days, 654 nm in 14. At 60 C polychroming is rapid, the absorption peak reaching 640-620 nm in 3 days. When the pH of the borax methylene blue solutions, normally about 9.0, is adjusted to pH 6.5, the absorption peak remains at 665 nm even when incubated at 60 C for extended periods. When used as a blood stain 0.4 ml borax methylene blue (1% methylene blue in 1% borax), 4 ml acetone, 2 ml borax-acid phosphate buffer to bring the solution to pH 6.5, and distilled water to make 40 ml, with 0.2 ml 1% eosin added just before using, an excellent Nocht-Giemsa type stain is achieved after 30 minutes staining. The material plasmodia P. falciparum, P. vivax, and P. berghei stain moderate blue with dark red chromatin and green to black pigment granules. The study confirms Malachowski's 1891 results and explains Gautier's 1896-98 failure to duplicate it.

  2. Eggshell spottiness reflects maternally transferred antibodies in blue tits.

    Directory of Open Access Journals (Sweden)

    Marie-Jeanne Holveck

    Full Text Available Blue-green and brown-spotted eggshells in birds have been proposed as sexual signals of female physiological condition and egg quality, reflecting maternal investment in the egg. Testing this hypothesis requires linking eggshell coloration to egg content, which is lacking for brown protoporphyrin-based pigmentation. As protoporphyrins can induce oxidative stress, and a large amount in eggshells should indicate either high female and egg quality if it reflects the female's high oxidative tolerance, or conversely poor quality if it reflects female physiological stress. Different studies supported either predictions but are difficult to compare given the methodological differences in eggshell-spottiness measurements. Using the blue tit Cyanistes caeruleus as a model species, we aimed at disentangling both predictions in testing if brown-spotted eggshell could reflect the quality of maternal investment in antibodies and carotenoids in the egg, and at improving between-study comparisons in correlating several common measurements of eggshell coloration (spectral and digital measures, spotted surface, pigmentation indices. We found that these color variables were weakly correlated highlighting the need for comparable quantitative measurements between studies and for multivariate regressions incorporating several eggshell-color characteristics. When evaluating the potential signaling function of brown-spotted eggshells, we thus searched for the brown eggshell-color variables that best predicted the maternal transfer of antibodies and carotenoids to egg yolks. We also tested the effects of several parental traits and breeding parameters potentially affecting this transfer. While eggshell coloration did not relate to yolk carotenoids, the eggs with larger and less evenly-distributed spots had higher antibody concentrations, suggesting that both the quantity and distribution of brown pigments reflected the transfer of maternal immune compounds in egg yolks

  3. The BlueSky Smoke Modeling Framework: Recent Developments

    Science.gov (United States)

    Sullivan, D. C.; Larkin, N.; Raffuse, S. M.; Strand, T.; ONeill, S. M.; Leung, F. T.; Qu, J. J.; Hao, X.

    2012-12-01

    BlueSky systems—a set of decision support tools including SmartFire and the BlueSky Framework—aid public policy decision makers and scientific researchers in evaluating the air quality impacts of fires. Smoke and fire managers use BlueSky systems in decisions about prescribed burns and wildland firefighting. Air quality agencies use BlueSky systems to support decisions related to air quality regulations. We will discuss a range of recent improvements to the BlueSky systems, as well as examples of applications and future plans. BlueSky systems have the flexibility to accept basic fire information from virtually any source and can reconcile multiple information sources so that duplication of fire records is eliminated. BlueSky systems currently apply information from (1) the National Oceanic and Atmospheric Administration's (NOAA) Hazard Mapping System (HMS), which represents remotely sensed data from the Moderate Resolution Imaging Spectroradiometer (MODIS), Advanced Very High Resolution Radiometer (AVHRR), and Geostationary Operational Environmental Satellites (GOES); (2) the Monitoring Trends in Burn Severity (MTBS) interagency project, which derives fire perimeters from Landsat 30-meter burn scars; (3) the Geospatial Multi-Agency Coordination Group (GeoMAC), which produces helicopter-flown burn perimeters; and (4) ground-based fire reports, such as the ICS-209 reports managed by the National Wildfire Coordinating Group. Efforts are currently underway to streamline the use of additional ground-based systems, such as states' prescribed burn databases. BlueSky systems were recently modified to address known uncertainties in smoke modeling associated with (1) estimates of biomass consumption derived from sparse fuel moisture data, and (2) models of plume injection heights. Additional sources of remotely sensed data are being applied to address these issues as follows: - The National Aeronautics and Space Administration's (NASA) Tropical Rainfall Measuring Mission

  4. Pengaruh Current Ratio, Asset Size, dan Earnings Variability terhadap Beta Pasar

    Directory of Open Access Journals (Sweden)

    Ahim Abdurahim

    2016-02-01

    Full Text Available The research objective was to determine the effect of variable accounting ie :, current ratio, asset size and earnings variability of the market beta. This study used 72 samples. Analyzer used to test the hypothesis that regression. Previous methods of Fowler and Rorke (1983 to adjust the market beta, and BLUE test is used to test classic assumptions of the independent variables are multikolinearitas, heteroskedasitas with Breushch-Pagan-Godfrey test, and autocorrelation with BG (The Breussh-Godfrey. The results found that the hypothesis H1a, H1b, H1c, and H2a powered means no influence current ratio, asset size and earnings variability of the market beta, both individually and simultaneously.

  5. A Survey of Blue-Noise Sampling and Its Applications

    KAUST Repository

    Yan, Dongming; Guo, Jian-Wei; Wang, Bin; Zhang, Xiao-Peng; Wonka, Peter

    2015-01-01

    In this paper, we survey recent approaches to blue-noise sampling and discuss their beneficial applications. We discuss the sampling algorithms that use points as sampling primitives and classify the sampling algorithms based on various aspects, e.g., the sampling domain and the type of algorithm. We demonstrate several well-known applications that can be improved by recent blue-noise sampling techniques, as well as some new applications such as dynamic sampling and blue-noise remeshing.

  6. A Survey of Blue-Noise Sampling and Its Applications

    KAUST Repository

    Yan, Dongming

    2015-05-05

    In this paper, we survey recent approaches to blue-noise sampling and discuss their beneficial applications. We discuss the sampling algorithms that use points as sampling primitives and classify the sampling algorithms based on various aspects, e.g., the sampling domain and the type of algorithm. We demonstrate several well-known applications that can be improved by recent blue-noise sampling techniques, as well as some new applications such as dynamic sampling and blue-noise remeshing.

  7. Aspen biology, community classification, and management in the Blue Mountains

    Science.gov (United States)

    David K. Swanson; Craig L. Schmitt; Diane M. Shirley; Vicky Erickson; Kenneth J. Schuetz; Michael L. Tatum; David C. Powell

    2010-01-01

    Quaking aspen (Populus tremuloides Michx.) is a valuable species that is declining in the Blue Mountains of northeastern Oregon. This publication is a compilation of over 20 years of aspen management experience by USDA Forest Service workers in the Blue Mountains. It includes a summary of aspen biology and occurrence in the Blue Mountains, and a...

  8. Implementation of EAM and FS potentials in HOOMD-blue

    Science.gov (United States)

    Yang, Lin; Zhang, Feng; Travesset, Alex; Wang, Caizhuang; Ho, Kaiming

    HOOMD-blue is a general-purpose software to perform classical molecular dynamics simulations entirely on GPUs. We provide full support for EAM and FS type potentials in HOOMD-blue, and report accuracy and efficiency benchmarks, including comparisons with the LAMMPS GPU package. Two problems were selected to test the accuracy: the determination of the glass transition temperature of Cu64.5Zr35.5 alloy using an FS potential and the calculation of pair distribution functions of Ni3Al using an EAM potential. In both cases, the results using HOOMD-blue are indistinguishable from those obtained by the GPU package in LAMMPS within statistical uncertainties. As tests for time efficiency, we benchmark time-steps per second using LAMMPS GPU and HOOMD-blue on one NVIDIA Tesla GPU. Compared to our typical LAMMPS simulations on one CPU cluster node which has 16 CPUs, LAMMPS GPU can be 3-3.5 times faster, and HOOMD-blue can be 4-5.5 times faster. We acknowledge the support from Laboratory Directed Research and Development (LDRD) of Ames Laboratory.

  9. Bactericidal effect of blue LED light irradiated TiO2/Fe3O4 particles on fish pathogen in seawater

    International Nuclear Information System (INIS)

    Cheng, T.C.; Yao, K.S.; Yeh, N.; Chang, C.I.; Hsu, H.C.; Gonzalez, F.; Chang, C.Y.

    2011-01-01

    This study uses blue LED light (λ max = 475 nm) activated TiO 2 /Fe 3 O 4 particles to evaluate the particles' photocatalytic activity efficiency and bactericidal effects in seawater of variable salinities. Different TiO 2 to Fe 3 O 4 mole ratios have been synthesized using sol-gel method. The synthesized particles contain mainly anatase TiO 2 , Fe 3 O 4 and FeTiO 3 . The study has identified TiO 2 /Fe 3 O 4 's bactericidal effect to marine fish pathogen (Photobacterium damselae subsp. piscicida BCRC17065) in seawater. The SEM photo reveals the surface destruction in bacteria incubated with blue LED irradiated TiO 2 /Fe 3 O 4 . The result of this study indicates that 1) TiO 2 /Fe 3 O 4 acquires photocatalytic activities in both the freshwater and the seawater via blue LED irradiation, 2) higher photocatalytic activities appear in solutions of higher TiO 2 /Fe 3 O 4 mole ratio, and 3) photocatalytic activity decreases as salinity increases. These results suggest that the energy saving blue LED light is a feasible light source to activate TiO 2 /Fe 3 O 4 photocatalytic activities in both freshwater and seawater.

  10. Characteristics of quantum open systems: free random variables approach

    International Nuclear Information System (INIS)

    Gudowska-Nowak, E.; Papp, G.; Brickmann, J.

    1998-01-01

    Random Matrix Theory provides an interesting tool for modelling a number of phenomena where noises (fluctuations) play a prominent role. Various applications range from the theory of mesoscopic systems in nuclear and atomic physics to biophysical models, like Hopfield-type models of neural networks and protein folding. Random Matrix Theory is also used to study dissipative systems with broken time-reversal invariance providing a setup for analysis of dynamic processes in condensed, disordered media. In the paper we use the Random Matrix Theory (RMT) within the formalism of Free Random Variables (alias Blue's functions), which allows to characterize spectral properties of non-Hermitean ''Hamiltonians''. The relevance of using the Blue's function method is discussed in connection with application of non-Hermitean operators in various problems of physical chemistry. (author)

  11. Collecting and displaying well-site data using BlueGauge technology

    Energy Technology Data Exchange (ETDEWEB)

    Morley, D.; Thiessen, N. [TR Labs, Calgary, AB (Canada)

    2004-07-01

    BlueGauge is a wireless technology solution for collecting and displaying well-site data, using off-the-shelf components and working at a distance of up to 100 meters. In addition, BlueGauge supports up to 255 sensors that monitor pressure, flow, or temperature. It was developed by TRLabs for an Edmonton-based company, for whom the prototype was built and tested. This presentation outlined the BlueGauge system architecture and hardware prototypes were demonstrated, including transceivers, embedded computers and pressure transducers. An overview of the software and its operating functions was presented, including screen shots. Operational benefits of BlueGauge technology include increased productivity through gathering process data quickly and easily, and the elimination of data entry errors. Safety was considered to be a primary benefit of BlueGauge equipment, particularly for monitoring dials and gauges in hard-to-access or hazardous locations. An additional safety benefit was the fact that BlueGauge has the ability to alert personnel when readings are outside of normal operating ranges. Details of installation and maintenance benefits include: ease of installation and relocation; support towards auto-discovery of new sensors; and the fact that no instrumentation cables or radio licence are required. Future plans were outlined and included a search for other companies interested in commercializing BlueGauge technology. tabs, figs.

  12. On the chemical variability of Middelburg glass beads and rods

    International Nuclear Information System (INIS)

    Karklins, K.; Kottman, J.; Hancock, R.G.V.; Sempowski, M.L.; Nohe, A.W.; Moreau, J.-F.; Aufreiter, S.; Kenyon, I.

    2001-01-01

    Forty-three glass samples from a late 16th-early 17th century, glass beadmaking house in Middelburg, the Netherlands, were selected for maximum colouring variability, including plain and multi-coloured varieties. The glass chemistries were quite diverse, within each colour grouping. For each single colour of glass, anticipated colouring elements (copper for turquoise blue, cobalt for dark blue, manganese for rose, and tin for white) were used, with the exception of two beads that were opacified wih antimony rather than with tin. Multi-coloured glass glasses (chevron beads) produced chemistries that match the mixing of the different coloured glasses. In some cases, low relative amounts of some inter-mixed glasses were not detectable against the composition of the major glass component. (author). 16 refs., 3 tabs

  13. Geology along the Blue Ridge Parkway in Virginia

    Science.gov (United States)

    Carter, Mark W.; Southworth, C. Scott; Tollo, Richard P.; Merschat, Arthur J.; Wagner, Sara; Lazor, Ava; Aleinikoff, John N.

    2017-01-01

    Detailed geologic mapping and new SHRIMP (sensitive high-resolution ion microprobe) U-Pb zircon, Ar/Ar, Lu-Hf, 14C, luminescence (optically stimulated), thermochronology (fission-track), and palynology reveal the complex Mesoproterozoic to Quaternary geology along the ~350 km length of the Blue Ridge Parkway in Virginia. Traversing the boundary of the central and southern Appalachians, rocks along the parkway showcase the transition from the para-autochthonous Blue Ridge anticlinorium of northern and central Virginia to the allochthonous eastern Blue Ridge in southern Virginia. From mile post (MP) 0 near Waynesboro, Virginia, to ~MP 124 at Roanoke, the parkway crosses the unconformable to faulted boundary between Mesoproterozoic basement in the core of the Blue Ridge anticlinorium and Neoproterozoic to Cambrian metasedimentary and metavolcanic cover rocks on the western limb of the structure. Mesoproterozoic basement rocks comprise two groups based on SHRIMP U-Pb zircon geochronology: Group I rocks (1.2-1.14 Ga) are strongly foliated orthogneisses, and Group II rocks (1.08-1.00 Ga) are granitoids that mostly lack obvious Mesoproterozoic deformational features.Neoproterozoic to Cambrian cover rocks on the west limb of the anticlinorium include the Swift Run and Catoctin Formations, and constituent formations of the Chilhowee Group. These rocks unconformably overlie basement, or abut basement along steep reverse faults. Rocks of the Chilhowee Group are juxtaposed against Cambrian rocks of the Valley and Ridge province along southeast- and northwest-dipping, high-angle reverse faults. South of the James River (MP 64), Chilhowee Group and basement rocks occupy the hanging wall of the nearly flat-lying Blue Ridge thrust fault and associated splays.South of the Red Valley high-strain zone (MP 144.5), the parkway crosses into the wholly allochthonous eastern Blue Ridge, comprising metasedimentary and meta-igneous rocks assigned to the Wills Ridge, Ashe, and Alligator

  14. Liquid crystal blue phases: stability, field effects and alignment

    OpenAIRE

    Gleeson, HF; Miller, RJ; Tian, L; Görtz, V; Goodby, JW

    2015-01-01

    The blue phases are fascinating structures in liquid crystals, fluids that exhibit cubic structures that have true crystalline order. The blue phases were discovered in the 1970s and were the subject of extensive research in the 1980s, when a deep understanding of many of their properties was established. The discovery that the blue phases could be stabilised to exist over wide temperature ranges meant that they became more than scientific curiosities and led to a recent resurgence in researc...

  15. Service design as an approach for recognizing blue ocean

    OpenAIRE

    Koskelo, Minna

    2013-01-01

    This thesis aims to show that service design as an approach can be utilized for discovering new market space, referred as blue ocean and new business opportunities, and thus to show that service design can be seen as an approach for bringing the new logic for value creation into strategic level. From the field of strategic management the theory of blue ocean strategy was chosen for presenting the strategic outcome and further since there are similarities be-tween blue ocean strategy approach ...

  16. “Key to the highway”: blues records and the great migration

    Directory of Open Access Journals (Sweden)

    Louis Mazzari

    2012-01-01

    Full Text Available This paper looks at the way “race record” blues of the 1920s and 1930s reinforced the decision of poor farmers, sharecroppers, and working men and women to move to the cities of the North. The theme is the way black southerners used the blues as the soundtrack of the Great Migration. In a sense, the Delta blues was a musical travel narrative for tens of thousands of people who were leaving the rural South for an unknown, modern and industrial future. The paper will explore blues music as an expression of the fluidity of African American society and culture during the Great Depression.While avoiding direct protest, blues singers and musicians—first women, later men—crafted an art form and employed the technology of the phonograph to encourage freedom of movement and choice. At the moment the “race record” industry was being born, and black farmers and families were quietly picking up and leaving the South, the music they traveled with was the blues. The paper will look at examples of blues singers whose records dealt specifically with the Great Migration and consider their influence on listeners.Cet article considère la manière dont le « race-record » blues des années 1920 et 1930 a renforcé la décision des agriculteurs, des métayers, et des ouvriers Afro-Américains d’émigrer vers les villes du nord. L’objectif général est de montrer comment les Afro-Américains se sont servi du blues comme accompagnement musical pour cette « grande migration ». En un sens, les vinyles de blues représentaient un récit de voyage musical pour des dizaines de milliers de personnes. Les chanteurs et les musiciens de blues ont conçu leur art et ont utilisé la technologie du phonographe en ayant pour but d’encourager la liberté de mouvement et de choix. Enfin, cet article examine en détail des exemples de disques de blues qui traitaient directement de la « grande migration », ainsi que leurs influences sur les musiciens et

  17. Blue-green photoluminescence in MCM-41 mesoporous nanotubes

    CERN Document Server

    Shen, J L; Lui, Y L; Cheng, P W; Cheng, C F

    2003-01-01

    Different photoluminescence (PL) techniques have been used to study the blue-green emission from siliceous MCM-41 nanotubes. It was found that the intensity of the blue-green PL is enhanced by rapid thermal annealing (RTA). This enhancement is explained by the generation of twofold-coordinated Si centres and non-bridging oxygen hole centres, in line with the surface properties of MCM-41. On the basis of the analysis of the PL following RTA, polarized PL, and PL excitation, we suggest that the triplet-to-singlet transition of twofold-coordinated silicon centres is responsible for the blue-green PL in MCM-41 nanotubes. (letter to the editor)

  18. Adsorption of methylene blue onto treated activated carbon

    International Nuclear Information System (INIS)

    Yamin Yasin; Mohd Zobir Hussein; Faujan Ahmad

    2007-01-01

    The potential feasibility of treated and untreated activated carbon for removal of methylene blue from aqueous solution was investigated. The effects of various experimental parameters such as contact time, solution pH and adsorbent dosage were investigated. The extent of methylene blue removal increased with the increased in contact time, solution pH and amount of adsorbent used. Adsorption data was better fitted to the Langmuir isotherm. The results in this study indicated that the treated activated carbon was an attractive candidate for removing organic dye of methylene blue which shows great reduction of colour while reducing the time contact to achieve equilibrium. (author)

  19. Multi-Epoch Hubble Space Telescope Observations of IZw18 : Characterization of Variable Stars at Ultra-Low Metallicities

    NARCIS (Netherlands)

    Fiorentino, G.; Ramos, R. Contreras; Clementini, G.; Marconi, M.; Musella, I.; Aloisi, A.; Annibali, F.; Saha, A.; Tosi, M.; van der Marel, R. P.

    2010-01-01

    Variable stars have been identified for the first time in the very metal-poor blue compact dwarf galaxy IZw18, using deep multi-band (F606W, F814W) time-series photometry obtained with the Advanced Camera for Surveys on board the Hubble Space Telescope. We detected 34 candidate variable stars in the

  20. Prussian blue as an antidote for radioactive thallium and cesium poisoning

    Directory of Open Access Journals (Sweden)

    Altagracia-Martinez M

    2012-06-01

    Full Text Available Marina Altagracia-Martínez, Jaime Kravzov-Jinich, Juan Manuel Martínez-Núñez, Camilo Ríos-Castañeda, Francisco López-NaranjoDepartments of Biological Systems and Health Care, Biological and Health Sciences Division, Universidad Autónoma Metropolitana-Xochimilco, Mexico DF, MexicoBackground: Following the attacks on the US on September 11, 2001, potentially millions of people might experience contamination from radioactive metals. However, before the specter of such accidents arose, Prussian blue was known only as an investigational agent for accidental thallium and cesium poisoning. The purpose of this review is to update the state of the art concerning use of Prussian blue as an effective and safe drug against possible bioterrorism attacks and to disseminate medical information in order to contribute to the production of Prussian blue as a biodefense drug.Methods: We compiled articles from a systematic review conducted from January 1, 1960 to March 30, 2011. The electronic databases consulted were Medline, PubMed, the Cochrane Library, and Scopus.Results: Prussian blue is effective and safe for use against radioactive intoxications involving cesium-137 and thallium. The US Food and Drug Administration has approved Prussian blue as a drug, but there is only one manufacturer providing Prussian blue to the US. Based on the evidence, Prussian blue is effective for use against radioactive intoxications involving cesium-137 and thallium, but additional clinical research on and production of Prussian blue are needed.Keywords: Prussian blue, radioactive cesium, thallium, intoxication, biodefense drug

  1. Can methylene blue dye be used as an alternative to patent blue dye to find the sentinel lymph node in breast cancer surgery?

    Directory of Open Access Journals (Sweden)

    Asieh Sadat Fattahi

    2014-01-01

    Full Text Available Background: Sentinel lymph node biopsy (SLNB is standard care to evaluate axillary involvement in early breast cancer. It has fewer complications than complete lymph node dissection; however, using blue dye in SLNB is controversial. We have evaluated the detection rate and local complications associated with methylene blue dye (MBD used in SLNB in early breast cancer patients and compared these results to patent blue dye (PBD. Materials and Methods : In a cohort prospective study, 312 patients with early breast cancer without axillary lymph node involvement were divided into two groups according to dye type. All of the patients received radiotracer and one type of blue dye. We filled out a checklist for the patients that contained demographic data, size of tumor, stage, detection of sentinel lymph node, and complications and then analyzed the data. Results: Demographic and histopathologic characteristics were not significantly different in both groups. Mean (standard deviation [SD] tumor size in all patients was 2.4 (0.8 cm. Detection rate in the MBD group was 77.5% with dye alone and 94.2% with dye and radioisotope; and in the PBD group it was 80.1% and 92.9% respectively (P > 0.05. We had blue discoloration of the skin in 23.7% in the PBD and 14.1% in the MBD group (P < 0.05 local inflammation was detected in one patient in the PBD and five in the MBD group (P < 0.05. Skin necrosis and systemic complications were not observed. Conclusion: Methylene blue has an acceptable detection rate, which may be a good alternative in SLNB. Complication such as blue discoloration of the skin was also lower with MBD.

  2. Microwave-assisted synthesis of graphene-Prussian Blue networked nanocomposites for electrocatalysis

    DEFF Research Database (Denmark)

    Zhang, Minwei; Ulstrup, Jens; Chi, Qijin

    There has been a great deal of interest recently in Prussian blue functional graphene. Due to they displayed advantage of both Prussian blue and graphene, we presented a one-pot and green method to synthesize interlocked graphene-Prussian Blue nanocomposites. Considering that graphene oxide (GO) ...

  3. BLUE OCEAN STRATEGY (BOS SEBAGAI PARADIGMA BARU MANAJEMEN PENDIDIKAN ISLAM

    Directory of Open Access Journals (Sweden)

    Ikhwan Fuad

    2016-08-01

    Full Text Available The focus of this article is to describe the Blue Ocean Strategy as a new paradigm of Islamic education management. the author seeks to elaborate on how the adoption of the Blue Ocean strategy of the business world to the world of education and answered the principles of what is accepted and rejected away from the theory. Adoption of blue ocean strategy is done by applying the universal principles are : among others reconstruct market boundaries, focus on the big picture rather than numbers, reach beyond existing demand, perform a series of strategies with appropriate, efforts to overcome organizational constraints and integrate execution into strategy. The principles of Blue Ocean Strategy Indicators that can be absorbed is an indicator that focuses gave excellent service and were not absorbed is a strong indicator of economic motivation. Generally, Blue Ocean Strategy quite well applied as a management paradigm of Islamic education.

  4. Blue LED irradiation to hydration of skin

    Science.gov (United States)

    Menezes, Priscila F. C.; Requena, Michelle B.; Lizarelli, Rosane F., Z.; Bagnato, Vanderlei S.

    2015-06-01

    Blue LED system irradiation shows many important properties on skin as: bacterial decontamination, degradation of endogenous skin chromophores and biostimulation. In this clinical study we prove that the blue light improves the skin hydration. In the literature none authors reports this biological property on skin. Then this study aims to discuss the role of blue light in the skin hydration. Twenty patients were selected to this study with age between 25-35 years old and phototype I, II and III. A defined area from forearm was pre determined (A = 4.0 cm2). The study was randomized in two treatment groups using one blue light device (power of 5.3mW and irradiance of 10.8mW/cm2). The first treatment group was irradiated with 3J/cm2 (277seconds) and the second with 6J/cm2 (555 seconds). The skin hydration evaluations were done using a corneometer. The measurements were collected in 7, 14, 21 and 30 days, during the treatment. Statistical test of ANOVA, Tukey and T-Student were applied considering 5% of significance. In conclusion, both doses were able to improve the skin hydration; however, 6J/cm2 has kept this hydration for 30 days.

  5. Blue and grey water footprint of textile industry in China.

    Science.gov (United States)

    Wang, Laili; Ding, Xuemei; Wu, Xiongying

    2013-01-01

    Water footprint (WF) is a newly developed idea that indicates impacts of freshwater appropriation and wastewater discharge. The textile industry is one of the oldest, longest and most complicated industrial chains in the world's manufacturing industries. However, the textile industry is also water intensive. In this paper, we applied a bottom-up approach to estimate the direct blue water footprint (WFdir,blue) and direct grey water footprint (WFdir,grey) of China's textile industry at sector level based on WF methodology. The results showed that WFdir,blue of China's textile industry had an increasing trend from 2001 to 2010. The annual WFdir,blue surpassed 0.92 Gm(3)/yr (giga cubic meter a year) since 2004 and rose to peak value of 1.09 Gm(3)/yr in 2007. The original and residuary WFdir,grey (both were calculated based on the concentration of chemical oxygen demand (CODCr)) of China's textile industry had a similar variation trend with that of WFdir,blue. Among the three sub-sectors of China's textile industry, the manufacture of textiles sector's annual WFdir,blue and WFdir,grey were much larger than those of the manufacture of textile wearing apparel, footware and caps sector and the manufacture of chemical fibers sector. The intensities of WFdir,blue and WF(res)dir,grey of China's textile industry were year by year decreasing through the efforts of issuing restriction policies on freshwater use and wastewater generation and discharge, and popularization of water saving and wastewater treatment technologies.

  6. Biological behaviour of buccal cells exposed to blue light

    International Nuclear Information System (INIS)

    Gritsch, Kerstin; Ponsonnet, Laurence; Schembri, Catherine; Farge, Pierre; Pourreyron, Laurence; Grosgogeat, Brigitte

    2008-01-01

    Blue light is used in dental practise to cure resin-based materials, but the path of the light often includes oral tissues such as gingival tissues. While adverse effects of blue light exposure on cells - such as retina cells - are well known, few studies have investigated the impact of blue light exposure on oral cells. The aim of the present in vitro study was to assess the biological effects of blue light emitted by two dental curing devices (a plasma-arc and a light-emitting diode curing unit) on human gingival fibroblasts. Light intensities and light-induced temperature rise were respectively measured with a radiometer and a thermocouple. Cellular response to blue light exposure was assessed by the observation of cell morphology (scanning electron microscopy) and the estimation of cell mitochondrial activity (MTT assay). Light intensities measured at the clinical distance were 488 ± 42 mW/cm 2 for the plasma-arc unit and ranged from 61 ± 5 to 140 ± 16 mW/cm 2 for the light-emitting diodes unit, according to the curing program used. The highest temperature rise was 0.5 and 3.5 deg. C for exposure to the plasma-arc light and to the light-emitting diodes light, respectively. Results showed no differences between exposed- and non-exposed cells in regards to cell morphology. However, cells exposed to blue light presented an increased mitochondrial activity compared to control cells (non-exposed), and mostly those exposed to plasma-arc light

  7. Compete or Leapfrog: Creating Blue Ocean through Entrepreneurial Orientation

    Directory of Open Access Journals (Sweden)

    Arslan Ayub

    2013-10-01

    Full Text Available The study analyzes the role of entrepreneurial orientation with mediating effect of knowledge creation process to creating Blue Ocean in corporate sector in Pakistan There is an increasing competition among companies due to globalization and technological advancements. Thus, it requires a study to measure the multifaceted influence of entrepreneurial orientation on knowledge creation process and Blue Ocean besides the actual paradigm of this terminology. This concept has been well discussed in this research arena since its inception in 2005. Numerous such initiatives have already been taken, however this concept invites a lot more addition, related companies are still in pursuit to materialize the research concepts. We highlight the contingencies in the shift from a red ocean to Blue Ocean. The study uses exploratory approach; primary data is collected from 391 professionals working in different sectors of Pakistan. The study uses structural equation model (SEM technique to test the hypotheses. The study found a positive relationship between entrepreneurial orientation and Blue Ocean, entrepreneurial orientation, knowledge creation process, and Blue Ocean. The study throws light on the importance of entrepreneurial orientation and knowledge creation process to head on this fast-paced competition.

  8. Crop damage of Eriotheca gracilipes (Bombacaceae by the Blue-Fronted Amazon (Amazona aestiva, Psittacidae, in the Brazilian Cerrado

    Directory of Open Access Journals (Sweden)

    J Ragusa-Netto

    Full Text Available Seed predation has major effects on the reproductive success of individuals, spatial patterns of populations, genetic variability, interspecific interactions and ultimately in the diversity of tree communities. At a Brazilian savanna, I evaluated the proportional crop loss of Eriotheca gracilipes due the Blue-Fronted Amazon (Amazona aestiva during a fruiting period. Also, I analyzed the relationship between proportional crop loss to Amazons and both fruit crop size and the distance from the nearest damaged conspecific. Trees produced from 1 to 109 fruits, so that Amazons foraged more often on trees bearing larger fruit crop size, while seldom visited less productive trees. Moreover, the relationship between fruit crop sizes and the number of depredated fruits was significant. However, when only damaged trees were assessed, I found a negative and significant relation between fruit crop size and proportional crop loss to Blue-Fronted Amazons. Taking into account this as a measure more directly related to the probability of seed survival, a negative density dependent effect emerged. Also, Amazons similarly damaged the fruit crops of either close or distant neighboring damaged trees. Hence, in spite of Blue-Fronted Amazons searched for E. gracilipes bearing large fruit crops, they were swamped due to the presence of more fruits than they could eat. Moderate seed predation by Blue-Fronted Amazons either at trees with large fruit crops or in areas where fruiting trees were aggregated implies in an enhanced probability of E. gracilipes seed survival and consequent regeneration success.

  9. Crop damage of Eriotheca gracilipes (Bombacaceae) by the Blue-Fronted Amazon (Amazona aestiva, Psittacidae), in the Brazilian Cerrado.

    Science.gov (United States)

    Ragusa-Netto, J

    2014-11-01

    Seed predation has major effects on the reproductive success of individuals, spatial patterns of populations, genetic variability, interspecific interactions and ultimately in the diversity of tree communities. At a Brazilian savanna, I evaluated the proportional crop loss of Eriotheca gracilipes due the Blue-Fronted Amazon (Amazona aestiva) during a fruiting period. Also, I analyzed the relationship between proportional crop loss to Amazons and both fruit crop size and the distance from the nearest damaged conspecific. Trees produced from 1 to 109 fruits, so that Amazons foraged more often on trees bearing larger fruit crop size, while seldom visited less productive trees. Moreover, the relationship between fruit crop sizes and the number of depredated fruits was significant. However, when only damaged trees were assessed, I found a negative and significant relation between fruit crop size and proportional crop loss to Blue-Fronted Amazons. Taking into account this as a measure more directly related to the probability of seed survival, a negative density dependent effect emerged. Also, Amazons similarly damaged the fruit crops of either close or distant neighboring damaged trees. Hence, in spite of Blue-Fronted Amazons searched for E. gracilipes bearing large fruit crops, they were swamped due to the presence of more fruits than they could eat. Moderate seed predation by Blue-Fronted Amazons either at trees with large fruit crops or in areas where fruiting trees were aggregated implies in an enhanced probability of E. gracilipes seed survival and consequent regeneration success.

  10. Posthuman blues

    CERN Document Server

    Tonnies, Mac

    2013-01-01

    Posthuman Blues, Vol. I is first volume of the edited version of the popular weblog maintained by author Mac Tonnies from 2003 until his tragic death in 2009. Tonnies' blog was a pastiche of his original fiction, reflections on his day-to-day life, trenchant observations of current events, and thoughts on an eclectic range of material he culled from the Internet. What resulted was a remarkably broad portrait of a thoughtful man and the complex times in which he lived, rendered with intellige...

  11. The monoamine oxidase inhibition properties of selected structural analogues of methylene blue

    International Nuclear Information System (INIS)

    Delport, Anzelle; Harvey, Brian H.; Petzer, Anél; Petzer, Jacobus P.

    2017-01-01

    The thionine dye, methylene blue (MB), is a potent inhibitor of monoamine oxidase (MAO) A, a property that may, at least in part, mediate its antidepressant effects in humans and animals. The central inhibition of MAO-A by MB has also been linked to serotonin toxicity (ST) which may arise when MB is used in combination with serotonergic drugs. Structural analogues and the principal metabolite of MB, azure B, have also been reported to inhibit the MAO enzymes, with all compounds exhibiting specificity for the MAO-A isoform. To expand on the structure-activity relationships (SARs) of MAO inhibition by MB analogues, the present study investigates the human MAO inhibition properties of five MB analogues: neutral red, Nile blue, new methylene blue, cresyl violet and 1,9-dimethyl methylene blue. Similar to MB, these analogues also are specific MAO-A inhibitors with cresyl violet (IC 50 = 0.0037 μM), Nile blue (IC 50 = 0.0077 μM) and 1,9-dimethyl methylene blue (IC 50 = 0.018 μM) exhibiting higher potency inhibition compared to MB (IC 50 = 0.07 μM). Nile blue also represents a potent MAO-B inhibitor with an IC 50 value of 0.012 μM. From the results it may be concluded that non-thionine MB analogues (e.g. cresyl violet and Nile blue) also may exhibit potent MAO inhibition, a property which should be considered when using these compounds in pharmacological studies. Benzophenoxazines such as cresyl violet and Nile blue are, similar to phenothiazines (e.g. MB), representative of high potency MAO-A inhibitors with a potential risk of ST. - Highlights: • MB analogues, cresyl violet and Nile blue, are high potency MAO-A inhibitors. • Nile blue also represents a potent MAO-B inhibitor. • Potent MAO-A inhibition should alert to potential serotonin toxicity.

  12. The monoamine oxidase inhibition properties of selected structural analogues of methylene blue

    Energy Technology Data Exchange (ETDEWEB)

    Delport, Anzelle [Pharmaceutical Chemistry, School of Pharmacy, North-West University, Private Bag X6001, Potchefstroom 2520 (South Africa); Centre of Excellence for Pharmaceutical Sciences, North-West University, Private Bag X6001, Potchefstroom 2520 (South Africa); Harvey, Brian H. [Centre of Excellence for Pharmaceutical Sciences, North-West University, Private Bag X6001, Potchefstroom 2520 (South Africa); Pharmacology, School of Pharmacy, North-West University, Private Bag X6001, Potchefstroom 2520 (South Africa); Petzer, Anél [Pharmaceutical Chemistry, School of Pharmacy, North-West University, Private Bag X6001, Potchefstroom 2520 (South Africa); Centre of Excellence for Pharmaceutical Sciences, North-West University, Private Bag X6001, Potchefstroom 2520 (South Africa); Petzer, Jacobus P., E-mail: jacques.petzer@nwu.ac.za [Pharmaceutical Chemistry, School of Pharmacy, North-West University, Private Bag X6001, Potchefstroom 2520 (South Africa); Centre of Excellence for Pharmaceutical Sciences, North-West University, Private Bag X6001, Potchefstroom 2520 (South Africa)

    2017-06-15

    The thionine dye, methylene blue (MB), is a potent inhibitor of monoamine oxidase (MAO) A, a property that may, at least in part, mediate its antidepressant effects in humans and animals. The central inhibition of MAO-A by MB has also been linked to serotonin toxicity (ST) which may arise when MB is used in combination with serotonergic drugs. Structural analogues and the principal metabolite of MB, azure B, have also been reported to inhibit the MAO enzymes, with all compounds exhibiting specificity for the MAO-A isoform. To expand on the structure-activity relationships (SARs) of MAO inhibition by MB analogues, the present study investigates the human MAO inhibition properties of five MB analogues: neutral red, Nile blue, new methylene blue, cresyl violet and 1,9-dimethyl methylene blue. Similar to MB, these analogues also are specific MAO-A inhibitors with cresyl violet (IC{sub 50} = 0.0037 μM), Nile blue (IC{sub 50} = 0.0077 μM) and 1,9-dimethyl methylene blue (IC{sub 50} = 0.018 μM) exhibiting higher potency inhibition compared to MB (IC{sub 50} = 0.07 μM). Nile blue also represents a potent MAO-B inhibitor with an IC{sub 50} value of 0.012 μM. From the results it may be concluded that non-thionine MB analogues (e.g. cresyl violet and Nile blue) also may exhibit potent MAO inhibition, a property which should be considered when using these compounds in pharmacological studies. Benzophenoxazines such as cresyl violet and Nile blue are, similar to phenothiazines (e.g. MB), representative of high potency MAO-A inhibitors with a potential risk of ST. - Highlights: • MB analogues, cresyl violet and Nile blue, are high potency MAO-A inhibitors. • Nile blue also represents a potent MAO-B inhibitor. • Potent MAO-A inhibition should alert to potential serotonin toxicity.

  13. Gamma irradiation of yellow and blue colorants in polystyrene packaging materials

    International Nuclear Information System (INIS)

    Komolprasert, V.; Diel, Todd; Sadler, G.

    2006-01-01

    The effect of 10- and 20-kGy gamma irradiation was studied on chromophtal yellow 2RLTS (Yellow 110-2, 3, 4, 5-tetrachloro-6-cyanobenzoic acid) and Irgalite Blue GBP (copper (II) phthalocyanine blue) colorants, which were added to polystyrene (PS) material used to package food prior to irradiation. Analytical results obtained suggest that irradiation did not generate any new chemicals in the PS polymer containing either yellow or blue colorant at a concentration of up to 1% (w/w). Both yellow and blue colorants are relatively stable to gamma irradiation

  14. China Mobile: Expanding "Blue Ocean"

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Driving force is crucial for realizing high-speed growth. The strong driving force from "Blue Ocean Strategy" is an important advantage for China Mobile to realize harmonious and leap-forward development.

  15. Fe K-edge XANES of Maya blue pigment

    Science.gov (United States)

    Río, M. Sánchez del; Sodo, A.; Eeckhout, S. G.; Neisius, T.; Martinetto, P.; Dooryhée, E.; Reyes-Valerio, C.

    2005-08-01

    The utilization of techniques used in Materials Science for the characterization of artefacts of interest for cultural heritage is getting more and more attention nowadays. One of the products of the ancient Maya chemistry is the "Maya blue" pigment, made with natural indigo and palygorskite. This pigment is different from any other pigment used in other parts of the world. It is durable and acid-resistant, and still keeps many secrets to scientists even though it has been studied for more than 50 years. Although the pigment is basically made of palygorskite Si8(Mg2Al2)O20(OH)2(OH2)4.4H2O and an organic colourant (indigo: C16H10N2O2), a number of other compounds have been found in previous studies on archaeological samples, like other clays and minerals, iron nanoparticles, iron oxides, impurities of transition metals (Cr, Mn, Ti, V), etc. We measured at the ESRF ID26 beamline the Fe K-edge XANES spectra of the blue pigment in ancient samples. They are compared to XANES spectra of Maya blue samples synthesized under controlled conditions, and iron oxides usually employed as pigments (hematite and goethite). Our results show that the iron found in ancient Maya blue pigment is related to the Fe exchanged in the palygorskite clay. We did not find iron in metallic form or goethite in archaeological Maya blue.

  16. Fe K-edge XANES of Maya blue pigment

    International Nuclear Information System (INIS)

    Rio, M. Sanchez del; Sodo, A.; Eeckhout, S.G.; Neisius, T.; Martinetto, P.; Dooryhee, E.; Reyes-Valerio, C.

    2005-01-01

    The utilization of techniques used in Materials Science for the characterization of artefacts of interest for cultural heritage is getting more and more attention nowadays. One of the products of the ancient Maya chemistry is the 'Maya blue' pigment, made with natural indigo and palygorskite. This pigment is different from any other pigment used in other parts of the world. It is durable and acid-resistant, and still keeps many secrets to scientists even though it has been studied for more than 50 years. Although the pigment is basically made of palygorskite Si 8 (Mg 2 Al 2 )O 20 (OH) 2 (OH 2 ) 4 .4H 2 O and an organic colourant (indigo: C 16 H 10 N 2 O 2 ), a number of other compounds have been found in previous studies on archaeological samples, like other clays and minerals, iron nanoparticles, iron oxides, impurities of transition metals (Cr, Mn, Ti, V), etc. We measured at the ESRF ID26 beamline the Fe K-edge XANES spectra of the blue pigment in ancient samples. They are compared to XANES spectra of Maya blue samples synthesized under controlled conditions, and iron oxides usually employed as pigments (hematite and goethite). Our results show that the iron found in ancient Maya blue pigment is related to the Fe exchanged in the palygorskite clay. We did not find iron in metallic form or goethite in archaeological Maya blue

  17. Physicochemical, Thermal, and Sensory Properties of Blue Corn (Zea Mays L.).

    Science.gov (United States)

    Mutlu, Ceren; Arslan-Tontul, Sultan; Candal, Cihadiye; Kilic, Ozlem; Erbas, Mustafa

    2018-01-01

    The aim of this study was to investigate some physicochemical and sensory properties of blue corn cultivated in Turkey. The length and width of the cob with kernels, hectoliter, and 1000-kernel weight of blue corn were measured as 7.66, 2.02 mm, 84.40 kg/100 L, and 44.27 g, respectively. The gelatinization onset, peak, and end temperatures were measured as 61.12 °C, 64.35 °C, and 75.65 °C, respectively. The water activity, moisture content, total protein, lipid, and crude fiber contents of the blue corn sample were detected as 0.44, 9.39%, 13.13%, 4.30%, and 2.68%, respectively. Total starch and resistant starch contents of blue corn were determined as 63.94% and 8.89%, respectively. Also, total monomeric anthocyanin content and antioxidant capacity of blue corn were detected as 915.43 mg CGE/kg and 7.99 μmol TE/g, respectively. Additionally, the major fatty acids detected in blue corn samples were palmitic, stearic, oleic, and linoleic acids. Blue corn can be utilized in the production of enjoyable and healthier snacks, such as popcorn and chips, because of its color and high phenolic, anthocyanin, and fiber contents. © 2017 Institute of Food Technologists®.

  18. THE TRANSATLANTIC BLUE DIPLOMACY

    Directory of Open Access Journals (Sweden)

    Ioana GUTU

    2016-12-01

    Full Text Available The international diplomatic environment has reached to an unprecedented development, involving one of the newly specialized diplomatic types, namely the economic diplomacy. At the core of the fast movements in the diplomatic spheres across the Globe are the international agreements like the Transatlantic Trade and Investment Partnership (TTIP that determined diplomacy to dissolve into new subtypes, evolving from ground to the ocean and implementing new ways of achieving economic and climate sustainability. One of the newly created diplomatic spheres, is the blue ocean diplomacy that acts mainly in accordance with the rules and regulations that are being applied to the transatlantic economy. Even though TTIP encourages the increase of trade flows across the Atlantic, it will also ease the foreign investment procedures that, under the approach of keeping a sustainable environment, will represent one of the most important initiatives in implementing the blue economy concept within the framework of the transatlantic diplomacy.

  19. OPTIMIZATION OF REACTIVE BLUE 19 DECOLORIZATION BY GANODERMA SP. USING RESPONSE SURFACE METHODOLOGY

    Directory of Open Access Journals (Sweden)

    1M. Mohammadian Fazli, *1A. R. Mesdaghinia, 1K. Naddafi, 1S. Nasseri , 1M. Yunesian, 2M. Mazaheri Assadi, 3S. Rezaie, 4H. Hamzehei

    2010-01-01

    Full Text Available Synthetic dyes are extensively used in different industries. Dyes have adverse impacts such as visual effects, chemical oxygen demand, toxicity, mutagenicity and carcinogenicity characteristics. White rot fungi, due to extracellular enzyme system, are capable to degrade dyes and various xenobiotics. The aim of this study was to optimize decolorization of reactive blue 19 (RB19 dye using Ganoderma sp. fungus. Response Surface Methodology (RSM was used to study the effect of independent variables, namely glycerol concentration (15, 20 and 25 g/L, temperature (27, 30 and 33 oC and pH (5.5, 6.0 and 6.5 on color removal efficiency in aqueous solution. From RSM-generated model, the optimum conditions for RB19 decolorization were identified to be at temperature of 27oC, glycerol concentration of 19.14 mg/L and pH=6.3. At the optimum conditions, predicted decolorization was 95.3 percent. The confirmatory experiments were conducted and confirmed the results by 94.89% color removal. Thus, this statistical approach enabled to improve reactive blue 19 decolorization process by Ganoderma sp. up to 1.27 times higher than non-optimized conditions.

  20. Removal of direct blue-86 from aqueous solution by new activated carbon developed from orange peel.

    Science.gov (United States)

    Nemr, Ahmed El; Abdelwahab, Ola; El-Sikaily, Amany; Khaled, Azza

    2009-01-15

    The use of low-cost, easy obtained, high efficiency and eco-friendly adsorbents has been investigated as an ideal alternative to the current expensive methods of removing dyes from wastewater. This study investigates the potential use of activated carbon prepared from orange peel for the removal of direct blue-86 (DB-86) (Direct Fast Turquoise Blue GL) dye from simulated wastewater. The effects of different system variables, adsorbent dosage, initial dye concentration, pH and contact time were studied. The results showed that as the amount of the adsorbent increased, the percentage of dye removal increased accordingly. Optimum pH value for dye adsorption was determined as approximately 2.0. Maximum dye was sequestered within 30min after the beginning for every experiment. The adsorption of direct blue-86 followed a pseudo-second-order rate equation and fit well Langmuir, Tempkin and Dubinin-Radushkevich (D-R) equations better than Freundlich and Redlich-Peterson equations. The maximum removal of direct blue-86 was obtained at pH 2 as 92% for adsorbent dose of 6gL(-1) and 100mgL(-1) initial dye concentration at room temperature. The maximum adsorption capacity obtained from Langmuir equation was 33.78mgg(-1). Furthermore, adsorption kinetics of DB-86 was studied and the rate of adsorption was found to conform to pseudo-second-order kinetics with a good correlation (R2>0.99) with intraparticle diffusion as one of the rate determining steps. Activated carbon developed from orange peel can be attractive options for dye removal from diluted industrial effluents since test reaction made on simulated dyeing wastewater show better removal percentage of DB-86.

  1. Blue Guardian: open architecture intelligence, surveillance, and reconnaissance (ISR) demonstrations

    Science.gov (United States)

    Shirey, Russell G.; Borntrager, Luke A.; Soine, Andrew T.; Green, David M.

    2017-04-01

    The Air Force Research Laboratory (AFRL) - Sensors Directorate has developed the Blue Guardian program to demonstrate advanced sensing technology utilizing open architectures in operationally relevant environments. Blue Guardian has adopted the core concepts and principles of the Air Force Rapid Capabilities Office (AFRCO) Open Mission Systems (OMS) initiative to implement an open Intelligence, Surveillance and Reconnaissance (ISR) platform architecture. Using this new OMS standard provides a business case to reduce cost and program schedules for industry and the Department of Defense (DoD). Blue Guardian is an early adopting program of OMS and provides much needed science and technology improvements, development, testing, and implementation of OMS for ISR purposes. This paper presents results and lessons learned under the Blue Guardian Project Shepherd program which conducted Multi-INT operational demonstrations in the Joint Interagency Task Force - South (JIATF-S) and USSOUTHCOM area of operations in early 2016. Further, on-going research is discussed to enhance Blue Guardian Multi-INT ISR capabilities to support additional mission sets and platforms, including unmanned operations over line of sight (LOS) and beyond line of sight (BLOS) datalinks. An implementation of additional OMS message sets and services to support off-platform sensor command and control using OMS/UCI data structures and dissemination of sensor product data/metadata is explored. Lastly, the Blue Guardian team is working with the AgilePod program to use OMS in a full Government Data Rights Pod to rapidly swap these sensors to different aircraft. The union of the AgilePod (which uses SOSA compliant standards) and OMS technologies under Blue Guardian programs is discussed.

  2. On the physical origin of blue-shifted hydrogen bonds.

    Science.gov (United States)

    Li, Xiaosong; Liu, Lei; Schlegel, H Bernhard

    2002-08-14

    For blue-shifted hydrogen-bonded systems, the hydrogen stretching frequency increases rather than decreases on complexation. In computations at various levels of theory, the blue-shift in the archetypical system, F(3)C-H.FH, is reproduced at the Hartree-Fock level, indicating that electron correlation is not the primary cause. Calculations also demonstrate that a blue-shift does not require either a carbon center or the absence of a lone pair on the proton donor, because F(3)Si-H.OH(2), F(2)NH.FH, F(2)PH.NH(3), and F(2)PH.OH(2) have substantial blue-shifts. Orbital interactions are shown to lengthen the X-H bond and lower its vibrational frequency, and thus cannot be the source of the blue-shift. In the F(3)CH.FH system, the charge redistribution in F(3)CH can be reproduced very well by replacing the FH with a simple dipole, which suggests that the interactions are predominantly electrostatic. When modeled with a point charge for the proton acceptor, attractive electrostatic interactions elongate the F(3)C-H, while repulsive interactions shorten it. At the equilibrium geometry of a hydrogen-bonded complex, the electrostatic attraction between the dipole moments of the proton donor and proton acceptor must be balanced by the Pauli repulsion between the two fragments. In the absence of orbital interactions that cause bond elongation, this repulsive interaction leads to compression of the X-H bond and a blue-shift in its vibrational frequency.

  3. Metal-nonmetal oscillations in doped blue phosphorene: a first-principles study

    Science.gov (United States)

    Li, Hui; Zhang, Liwei; Cai, Xiaolin; Li, Xiaohua; Wang, Baoji; Yu, Weiyang; Zhao, Ruiqi

    2018-05-01

    Based on density functional theory (DFT), we have systematically investigated the geometry structure and electronic properties of group IIIA, IVA, VA, and VIA atoms doped blue phosphorene, such as B‑, C‑, N‑, O‑, Al‑, Si- and S-doped blue phosphorene systems. We find that the electronic properties of blue phosphorene are drastically modified by the number of valence electrons in dopant atoms. An intriguing general rule of metal-nonmetal oscillations have been obtained that the dopant atoms from even group, such as IVA and VIA, lead to metal properties, while dopant atoms from odd group, such as IIIA and VA, give rise to semiconductor properties, which is different from traditional n or p doping effect in bulk case. This even–odd oscillating behavior is attributed to the peculiar bonding characteristics of blue phosphorene and the strong hybridization of sp orbitals between dopants and blue phosphorene. Then the underlying mechanism has been investigated with the electronic filling analysis. These results pave an intriguing way to tune the transport properties of electronic and photoelectronic devices based on blue phosphorene.

  4. Directed self-assembly of liquid crystalline blue-phases into ideal single-crystals

    Science.gov (United States)

    Martínez-González, Jose A.; Li, Xiao; Sadati, Monirosadat; Zhou, Ye; Zhang, Rui; Nealey, Paul F.; de Pablo, Juan J.

    2017-06-01

    Chiral nematic liquid crystals are known to form blue phases--liquid states of matter that exhibit ordered cubic arrangements of topological defects. Blue-phase specimens, however, are generally polycrystalline, consisting of randomly oriented domains that limit their performance in applications. A strategy that relies on nano-patterned substrates is presented here for preparation of stable, macroscopic single-crystal blue-phase materials. Different template designs are conceived to exert control over different planes of the blue-phase lattice orientation with respect to the underlying substrate. Experiments are then used to demonstrate that it is indeed possible to create stable single-crystal blue-phase domains with the desired orientation over large regions. These results provide a potential avenue to fully exploit the electro-optical properties of blue phases, which have been hindered by the existence of grain boundaries.

  5. Variability in the Water Footprint of Arable Crop Production across European Regions

    Directory of Open Access Journals (Sweden)

    Anne Gobin

    2017-02-01

    Full Text Available Crop growth and yield are affected by water use during the season: the green water footprint (WF accounts for rain water, the blue WF for irrigation and the grey WF for diluting agri-chemicals. We calibrated crop yield for FAO’s water balance model “Aquacrop” at field level. We collected weather, soil and crop inputs for 45 locations for the period 1992–2012. Calibrated model runs were conducted for wheat, barley, grain maize, oilseed rape, potato and sugar beet. The WF of cereals could be up to 20 times larger than the WF of tuber and root crops; the largest share was attributed to the green WF. The green and blue WF compared favourably with global benchmark values (R2 = 0.64–0.80; d = 0.91–0.95. The variability in the WF of arable crops across different regions in Europe is mainly due to variability in crop yield ( c v ¯ = 45% and to a lesser extent to variability in crop water use ( c v ¯ = 21%. The WF variability between countries ( c v ¯ = 14% is lower than the variability between seasons ( c v ¯ = 22% and between crops ( c v ¯ = 46%. Though modelled yields increased up to 50% under sprinkler irrigation, the water footprint still increased between 1% and 25%. Confronted with drainage and runoff, the grey WF tended to overestimate the contribution of nitrogen to the surface and groundwater. The results showed that the water footprint provides a measurable indicator that may support European water governance.

  6. Photometry of faint blue stars

    International Nuclear Information System (INIS)

    Kilkenny, D.; Hill, P.W.; Brown, A.

    1977-01-01

    Photometry on the uvby system is given for 61 faint blue stars. The stars are classified by means of the Stromgren indices, using criteria described in a previous paper (Kilkenny and Hill (1975)). (author)

  7. Blue-Green Solutions in Urban Development

    Science.gov (United States)

    Karlsson, Caroline; Kalantari, Zahra

    2017-04-01

    With the ongoing urbanisation and increasing pressure for new housing and infrastructure, the nexus of developing compact, energy-efficient and yet liveable and sustainable cities is urgent to address. In this context, blue-green spaces and related ecosystem services (ES) are critical resources that need to be integrated in policy and planning of urban. Among the ES provided by blue-green spaces, regulating ES such as water retention and purification are particularly important in urban areas, affecting water supply and quality, related cultural ES and biodiversity, as well as cities potential to adapt to climate change. Blue-green infrastructure management is considered a sustainable way to reducing negative effects of urbanisation, such as decreasing flood risks, as well as adapting to climate change for example by controlling increasing flood and drought risks. Blue-green infrastructure management can for example create multifunctional surfaces with valuable environmental and social functions and generally handle greenways and ecological networks as important ecosystem service components, for example for stormwater regulation in a sustainable urban drainage system. The Norrström drainage basin (22,000 km2) is a large demonstrator for Blue-green infrastructure management. Both urbanisation and agriculture are extensive within this basin, which includes the Swedish capital Stockholm and is part of the fertile Swedish belt. Together, the relatively high population density combined with agricultural and industrial activities in this region imply large eutrophication and pollution pressures, not least transferred through storm runoff to both inland surface waters and the coastal waters of the Baltic Sea. The ecosystems of this basin provide highly valued but also threatened services. For example, Lake Mälaren is the single main freshwater supply for the Swedish capital Stockholm, as well as a key nutrient retention system that strongly mitigates waterborne nutrient

  8. In vivo biocompatibility evaluation of Cibacron blue-agarose.

    Science.gov (United States)

    Kao, J M; Rose, R; Yousef, M; Hunter, S K; Rodgers, V G

    1999-12-15

    This study investigated the biocompatibility of Cibacron blue-agarose as a biomaterial for microencapsulation. Cibacron blue-agarose is known to have an affinity for albumin under certain pH conditions and in the proper steric environment. Thus it was postulated that the material's high affinity for host albumin might reduce a secondary immune response and reduce the fibrotic overgrowth that often accompanies transplanted foreign materials. In vivo tests were performed using the Lewis rat model. Both Cibacron blue-agarose and plain agarose disks were prepared, with some disks from each group being pre-exposed to sera from Lewis rats. The disks were transplanted into the peritoneal cavities of Lewis rats. After 115 days the disks were excised. Fibrotic overgrowth was analyzed using light microscopy, and a blind study was used to measure the average growth thickness on each disk. The results demonstrated that all disks developed some fibrotic encapsulation and that the presence of Cibacron blue was not significant in reducing fibrotic overgrowth (p = 0.62). Agarose disks pre-exposed to sera had significantly less average overgrowth than any other group (p = 0. 06). Copyright 1999 John Wiley & Sons, Inc.

  9. FROM CIRCULAR ECONOMY TO BLUE ECONOMY

    Directory of Open Access Journals (Sweden)

    Iustin-Emanuel, ALEXANDRU

    2014-11-01

    Full Text Available Addressing the subject of this essay is based on the background ideas generated by a new branch of science - Biomimicry. According to European Commissioner for the Environment, "Nature is the perfect model of circular economy". Therefore, by imitating nature, we are witnessing a process of cycle redesign: production-consumption-recycling. The authors present some reflections on the European Commission's decision to adopt after July 1, 2014 new measures concerning the development of more circular economies. Starting from the principles of Ecolonomy, which is based on the whole living paradigm, this paper argues for the development within each economy of entrepreneurial policies related to the Blue economy. In its turn, Blue economy is based on scientific analyses that identify the best solutions in a business. Thus, formation of social capital will lead to healthier and cheaper products, which will stimulate entrepreneurship. Blue economy is another way of thinking economic practice and is a new model of business design. It is a healthy, sustainable business, designed for people. In fact, it is the core of the whole living paradigm through which, towards 2020, circular economy will grow more and more.

  10. Ancient origin and maternal inheritance of blue cuckoo eggs.

    Science.gov (United States)

    Fossøy, Frode; Sorenson, Michael D; Liang, Wei; Ekrem, Torbjørn; Moksnes, Arne; Møller, Anders P; Rutila, Jarkko; Røskaft, Eivin; Takasu, Fugo; Yang, Canchao; Stokke, Bård G

    2016-01-12

    Maternal inheritance via the female-specific W chromosome was long ago proposed as a potential solution to the evolutionary enigma of co-existing host-specific races (or 'gentes') in avian brood parasites. Here we report the first unambiguous evidence for maternal inheritance of egg colouration in the brood-parasitic common cuckoo Cuculus canorus. Females laying blue eggs belong to an ancient (∼2.6 Myr) maternal lineage, as evidenced by both mitochondrial and W-linked DNA, but are indistinguishable at nuclear DNA from other common cuckoos. Hence, cuckoo host races with blue eggs are distinguished only by maternally inherited components of the genome, which maintain host-specific adaptation despite interbreeding among males and females reared by different hosts. A mitochondrial phylogeny suggests that blue eggs originated in Asia and then expanded westwards as female cuckoos laying blue eggs interbred with the existing European population, introducing an adaptive trait that expanded the range of potential hosts.

  11. Hole-Size Increasing PCFs for Blue-Extended Supercontinuum Generation

    DEFF Research Database (Denmark)

    Sørensen, Simon Toft; Larsen, Casper; Jakobsen, C.

    2013-01-01

    into the deep-blue in a single mode PCF with varying hole-size and pitch fabricated directly at the draw-tower. The PCFs in this work are fabricated by increasing the pressure on the air holes during the drawing. However, this process alone will lead to an undesirable structure where both the relative hole......Supercontinuum (SC) sources with spectra extending into the deep-blue region below 400 nm are highly desirable in areas such as fluorescent microscopy [1]. Tapering of photonic crystal fibers (PCFs) with high air-fill fractions has proven an effective way of extending the spectra into the deep...... wavelength spectral edge to wavelengths in the deep-blue or even UV. Previous reports on blue-extended SC generation were typically achieved in tapered PCFs where the air-hole structure was preserved [1-4], i.e. the relative hole-size constant. However, such PCFs with high air-fill fractions are inevitably...

  12. The "Blue Banana" Revisited

    NARCIS (Netherlands)

    Faludi, A.K.F.

    2015-01-01

    This essay is about the “Blue Banana”. Banana is the name given subsequently by others to a Dorsale européenne (European backbone) identified empirically by Roger Brunet. In a background study to the Communication of the European Commission ‘Europe 2000’, Klaus Kunzmann and Michael Wegener put

  13. The University of Montana's Blue Mountain Observatory

    Science.gov (United States)

    Friend, D. B.

    2004-12-01

    The University of Montana's Department of Physics and Astronomy runs the state of Montana's only professional astronomical observatory. The Observatory, located on nearby Blue Mountain, houses a 16 inch Boller and Chivens Cassegrain reflector (purchased in 1970), in an Ash dome. The Observatory sits just below the summit ridge, at an elevation of approximately 6300 feet. Our instrumentation includes an Op-Tec SSP-5A photoelectric photometer and an SBIG ST-9E CCD camera. We have the only undergraduate astronomy major in the state (technically a physics major with an astronomy option), so our Observatory is an important component of our students' education. Students have recently carried out observing projects on the photometry of variable stars and color photometry of open clusters and OB associations. In my poster I will show some of the data collected by students in their observing projects. The Observatory is also used for public open houses during the summer months, and these have become very popular: at times we have had 300 visitors in a single night.

  14. Fe K-edge XANES of Maya blue pigment

    Energy Technology Data Exchange (ETDEWEB)

    Rio, M. Sanchez del [ESRF, Experiments Division, B.P. 220, F-38043, Grenoble Cedex (France)]. E-mail: srio@esrf.fr; Sodo, A. [ESRF, Experiments Division, B.P. 220, F-38043, Grenoble Cedex (France); Eeckhout, S.G. [ESRF, Experiments Division, B.P. 220, F-38043, Grenoble Cedex (France); Neisius, T. [ESRF, Experiments Division, B.P. 220, F-38043, Grenoble Cedex (France); Martinetto, P. [Laboratoire de Cristallographie, CNRS, Grenoble B.P. 166, F-38042, Grenoble Cedex 09 (France); Dooryhee, E. [Laboratoire de Cristallographie, CNRS, Grenoble B.P. 166, F-38042, Grenoble Cedex 09 (France); Reyes-Valerio, C. [INAH, Mexico DF (Mexico)

    2005-08-15

    The utilization of techniques used in Materials Science for the characterization of artefacts of interest for cultural heritage is getting more and more attention nowadays. One of the products of the ancient Maya chemistry is the 'Maya blue' pigment, made with natural indigo and palygorskite. This pigment is different from any other pigment used in other parts of the world. It is durable and acid-resistant, and still keeps many secrets to scientists even though it has been studied for more than 50 years. Although the pigment is basically made of palygorskite Si{sub 8}(Mg{sub 2}Al{sub 2})O{sub 20}(OH){sub 2}(OH{sub 2}){sub 4}.4H{sub 2}O and an organic colourant (indigo: C{sub 16}H{sub 10}N{sub 2}O{sub 2}), a number of other compounds have been found in previous studies on archaeological samples, like other clays and minerals, iron nanoparticles, iron oxides, impurities of transition metals (Cr, Mn, Ti, V), etc. We measured at the ESRF ID26 beamline the Fe K-edge XANES spectra of the blue pigment in ancient samples. They are compared to XANES spectra of Maya blue samples synthesized under controlled conditions, and iron oxides usually employed as pigments (hematite and goethite). Our results show that the iron found in ancient Maya blue pigment is related to the Fe exchanged in the palygorskite clay. We did not find iron in metallic form or goethite in archaeological Maya blue.

  15. Dyes adsorption blue vegetable and blue watercolor by natural zeolites modified with surfactants;Adsorcion de colorantes azul vegetal y azul acuarela por zeolitas naturales modificadas con surfactantes

    Energy Technology Data Exchange (ETDEWEB)

    Jardon S, C. C.; Olguin G, M. T. [ININ, Departamento de Quimica, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Diaz N, M. C., E-mail: teresa.olguin@inin.gob.m [Instituto Tecnologico de Toluca, Av. Instituto Tecnologico s/n, Ex-Rancho la Virgen, 52140 Metepec, Estado de Mexico (Mexico)

    2009-07-01

    In this work was carried out the dyes removal blue vegetable and blue watercolor of aqueous solutions, to 20 C, at different times and using a zeolite mineral of Parral (Chihuahua, Mexico) modified with hexadecyl trimethyl ammonium bromide or dodecyl trimethyl ammonium bromide. The zeolite was characterized before and after of its adaptation with NaCl and later with HDTMABr and DTMABr. For the materials characterization were used the scanning electron microscopy of high vacuum; elementary microanalysis by X-ray spectroscopy of dispersed energy and X-ray diffraction techniques. It was found that the surfactant type absorbed in the zeolite material influences on the adsorption process of the blue dye. Likewise, the chemical structure between the vegetable blue dye and the blue watercolor, determines the efficiency of the color removal of the water, by the zeolites modified with the surfactants. (Author)

  16. Phototropin 1 and dim-blue light modulate the red light de-etiolation response.

    Science.gov (United States)

    Wang, Yihai; M Folta, Kevin

    2014-01-01

    Light signals regulate seedling morphological changes during de-etiolation through the coordinated actions of multiple light-sensing pathways. Previously we have shown that red-light-induced hypocotyl growth inhibition can be reversed by addition of dim blue light through the action of phototropin 1 (phot1). Here we further examine the fluence-rate relationships of this blue light effect in short-term (hours) and long-term (days) hypocotyl growth assays. The red stem-growth inhibition and blue promotion is a low-fluence rate response, and blue light delays or attenuates both the red light and far-red light responses. These de-etiolation responses include blue light reversal of red or far-red induced apical hook opening. This response also requires phot1. Cryptochromes (cry1 and cry2) are activated by higher blue light fluence-rates and override phot1's influence on hypocotyl growth promotion. Exogenous application of auxin transport inhibitor naphthylphthalamic acid abolished the blue light stem growth promotion in both hypocotyl growth and hook opening. Results from the genetic tests of this blue light effect in auxin transporter mutants, as well as phytochrome kinase substrate mutants indicated that aux1 may play a role in blue light reversal of red light response. Together, the phot1-mediated adjustment of phytochrome-regulated photomorphogenic events is most robust in dim blue light conditions and is likely modulated by auxin transport through its transporters.

  17. Isolation and Characterization of Blue Green Algae from Egyptian ...

    African Journals Online (AJOL)

    meldemellawy

    2014-02-20

    Feb 20, 2014 ... aminotransferase (AMT) domains of the mycE and ndaF genes (Jungblut et al., 2006) allowing detection of microcystin and nodularin-producing cyanobacteria. MATERIALS AND METHODS. Isolation and cultivation of blue green algae. Blue green algae had been isolated from soil of Rice field in river.

  18. Ontwikkeling van een BlueJ-getinte uitbreiding voor NetBeans

    OpenAIRE

    Boutsen, Stijn

    2017-01-01

    BlueJ is een open-source IDE die het aanleren van object georiënteerd programmeren in JAVA vergemakkelijkt. Dit programma wordt gebruikt in 1BA maar is niet geschikt om grote applicaties te schrijven. Door het ontbreken van de educatieve tools van BlueJ hebben studenten moeilijkheden met de overgang naar een professionele programmeeromgeving zoals de NetBeans IDE. Deze masterproef realiseert een plugin voor NetBeans met de belangrijkste educatieve kenmerken van BlueJ. Zowel het visueel kla...

  19. Seasonal and geographic variation of southern blue whale subspecies in the Indian Ocean.

    Directory of Open Access Journals (Sweden)

    Flore Samaran

    Full Text Available Understanding the seasonal movements and distribution patterns of migratory species over ocean basin scales is vital for appropriate conservation and management measures. However, assessing populations over remote regions is challenging, particularly if they are rare. Blue whales (Balaenoptera musculus spp are an endangered species found in the Southern and Indian Oceans. Here two recognized subspecies of blue whales and, based on passive acoustic monitoring, four "acoustic populations" occur. Three of these are pygmy blue whale (B.m. brevicauda populations while the fourth is the Antarctic blue whale (B.m. intermedia. Past whaling catches have dramatically reduced their numbers but recent acoustic recordings show that these oceans are still important habitat for blue whales. Presently little is known about the seasonal movements and degree of overlap of these four populations, particularly in the central Indian Ocean. We examined the geographic and seasonal occurrence of different blue whale acoustic populations using one year of passive acoustic recording from three sites located at different latitudes in the Indian Ocean. The vocalizations of the different blue whale subspecies and acoustic populations were recorded seasonally in different regions. For some call types and locations, there was spatial and temporal overlap, particularly between Antarctic and different pygmy blue whale acoustic populations. Except on the southernmost hydrophone, all three pygmy blue whale acoustic populations were found at different sites or during different seasons, which further suggests that these populations are generally geographically distinct. This unusual blue whale diversity in sub-Antarctic and sub-tropical waters indicates the importance of the area for blue whales in these former whaling grounds.

  20. Modification Of Cesium Toxicity By Prussian Blue In Adult Male Albino Rats

    International Nuclear Information System (INIS)

    MANGOOD, S.A.; HAGGAG, A.M.

    2009-01-01

    The purposes of this study were to asses the toxicological effects of stable cesium chloride, and investigate the possible therapeutic role of Prussian blue (PB) in adult male albino rats.Thirty two adult male albino rats were used in this study and classified to 4 groups (8 rats/group) as follows:1- Group one (G1): rats were considered as controls and kept on the commercial diet without any treatments.2-Group two (G2): treated with daily oral cesium chloride (50 mg/300 g body weight).3-Group three (G3): treated with daily oral Prussian blue (250 mg/rats).4-Group four (G4): treated with cesium chloride at a daily oral dose of 50 mg/300 g body weight + Prussian blue at a daily oral dose of 250 mg/rats.All animals were administered the CsCl and/or PB via intubation tube and the duration of this study was 35 consecutive days. Hemoglobin (Hb), hematocrit (Ht%), red blood cells (RBC), white blood cells (WBC), folic acid, vitamin B12, total protein, albumin, globulin, A/G ratio, ALT, AST, total bilirubin, alkaline phosphatase, blood glucose, urea, creatinine, creatine phosphokinase (CPK), lactate dehydrogenase (LDH), sodium, potassium, calcium and inorganic phosphorous and body weight were determined in all groups.The data obtained revealed that the intake of stable cesium chloride in adult male rats caused significant decreases in the Hb, hematocrit, folic acid, vitamin B12 and potassium contents, with significant increases in WBC count, urea and creatinine levels and no effect on the other parameters. On the other hand, PB as a therapeutic agent caused significant amelioration in the changes produced by CsCl with variable degrees leading to the conclusion that the therapeutic agents might provide a protection against the toxicological effects of CsCl.

  1. The spatially resolved characterisation of Egyptian blue, Han blue and Han purple by photo-induced luminescence digital imaging.

    Science.gov (United States)

    Verri, G

    2009-06-01

    The photo-induced luminescence properties of Egyptian blue, Han blue and Han purple were investigated by means of near-infrared digital imaging. These pigments emit infrared radiation when excited in the visible range. The emission can be recorded by means of a modified commercial digital camera equipped with suitable glass filters. A variety of visible light sources were investigated to test their ability to excite luminescence in the pigments. Light-emitting diodes, which do not emit stray infrared radiation, proved an excellent source for the excitation of luminescence in all three compounds. In general, the use of visible radiation emitters with low emission in the infrared range allowed the presence of the pigments to be determined and their distribution to be spatially resolved. This qualitative imaging technique can be easily applied in situ for a rapid characterisation of materials. The results were compared to those for Egyptian green and for historical and modern blue pigments. Examples of the application of the technique on polychrome works of art are presented.

  2. Blue eyes in lemurs and humans: same phenotype, different genetic mechanism

    DEFF Research Database (Denmark)

    Bradley, Brenda J; Pedersen, Anja; Mundy, Nicholas I

    2009-01-01

    Almost all mammals have brown or darkly-pigmented eyes (irises), but among primates, there are some prominent blue-eyed exceptions. The blue eyes of some humans and lemurs are a striking example of convergent evolution of a rare phenotype on distant branches of the primate tree. Recent work...... on humans indicates that blue eye color is associated with, and likely caused by, a single nucleotide polymorphism (rs12913832) in an intron of the gene HERC2, which likely regulates expression of the neighboring pigmentation gene OCA2. This raises the immediate question of whether blue eyes in lemurs might...... have a similar genetic basis. We addressed this by sequencing the homologous genetic region in the blue-eyed black lemur (Eulemur macaco flavifrons; N = 4) and the closely-related black lemur (Eulemur macaco macaco; N = 4), which has brown eyes. We then compared a 166-bp segment corresponding...

  3. Reverse leakage current characteristics of InGaN/GaN multiple quantum well ultraviolet/blue/green light-emitting diodes

    Science.gov (United States)

    Zhou, Shengjun; Lv, Jiajiang; Wu, Yini; Zhang, Yuan; Zheng, Chenju; Liu, Sheng

    2018-05-01

    We investigated the reverse leakage current characteristics of InGaN/GaN multiple quantum well (MQW) near-ultraviolet (NUV)/blue/green light-emitting diodes (LEDs). Experimental results showed that the NUV LED has the smallest reverse leakage current whereas the green LED has the largest. The reason is that the number of defects increases with increasing nominal indium content in InGaN/GaN MQWs. The mechanism of the reverse leakage current was analyzed by temperature-dependent current–voltage measurement and capacitance–voltage measurement. The reverse leakage currents of NUV/blue/green LEDs show similar conduction mechanisms: at low temperatures, the reverse leakage current of these LEDs is attributed to variable-range hopping (VRH) conduction; at high temperatures, the reverse leakage current of these LEDs is attributed to nearest-neighbor hopping (NNH) conduction, which is enhanced by the Poole–Frenkel effect.

  4. Detection and identification of dyes in blue writing inks by LC-DAD-orbitrap MS.

    Science.gov (United States)

    Sun, Qiran; Luo, Yiwen; Yang, Xu; Xiang, Ping; Shen, Min

    2016-04-01

    In the field of forensic questioned document examination, to identify dyes detected in inks not only provides a solid foundation for ink discrimination in forged contents identification, but also facilitates the investigation of ink origin or the study regarding ink dating. To detect and identify potential acid and basic dyes in blue writing inks, a liquid chromatography-diode array detection-Orbitrap mass spectrometry (LC-DAD-Orbitrap MS) method was established. Three sulfonic acid dyes (Acid blue 1, Acid blue 9 and Acid red 52) and six triphenylmethane basic dyes (Ethyl violet, Crystal violet, Methyl violet 2B, Basic blue 7, Victoria blue B and Victoria blue R) were employed as reference dyes for method development. Determination of the nine dyes was validated to evaluate the instrument performance, and it turned out to be sensitive and stable enough for quantification. The method was then applied in the screening analysis of ten blue roller ball pen inks and twenty blue ballpoint pen inks. As a result, including TPR (a de-methylated product of Crystal violet), ten known dyes and four unknown dyes were detected in the inks. The latter were further identified as a de-methylated product of Victoria blue B, Acid blue 104, Acid violet 49 and Acid blue 90, through analyzing their characteristic precursor and product ions acquired by Orbitrap MS with good mass accuracy. The results showed that the established method is capable of detecting and identifying potential dyes in blue writing inks. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  5. Temperature Dependence of the Moessbauer Effect on Prussian Blue Nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Zhou Pingheng; Xue Desheng; Luo Haiqing; Shi Huigang [Lanzhou University, Key Lab for Magnetism and Magnetic Materials of MOE (China)

    2002-09-15

    Highly ordered Prussian blue nanowires with diameter of about 50 nm and length up to 4 {mu}m have been fabricated by an electrodepositing technology with two-step anodizing anodic aluminum oxide films. The Moessbauer spectra taken between 15 and 300 K indicate that the hyperfine parameters decrease as the temperature increases. The temperature dependence of the quadrupole splitting, the isomer shift and the spectra area are discussed. A decrease of Debye temperature for Prussian blue nanowires was found with respect to that of Prussian blue bulk.

  6. Full Color Camouflage in a Printable Photonic Blue-Colored Polymer

    OpenAIRE

    Moirangthem, Monali; Schenning, Albertus P. H. J.

    2018-01-01

    A blue reflective photonic polymer coating which can be patterned in full color, from blue to red, by printing with an aqueous calcium nitrate solution has been fabricated. Color change in the cholesteric liquid-crystalline polymer network over the entire visible spectrum is obtained by the use of nonreactive mesogen. The pattern in the coating is hidden in the blue color dry state and appears upon exposure to water or by exhaling breath onto it due to different degrees of swelling of the pol...

  7. New photo-convertible reactions of blue-fluorescent calf α-crystallin

    International Nuclear Information System (INIS)

    Fujimori, E.

    1979-01-01

    Both native blue fluorescent α-crystalline from calf lenses and UV (300 nm)-irradiated blue-fluorescent α-crystalline, when further irradiated with 365 nm-UV light, produce photo-products capable of emitting a new fluorescence at 455 nm. Illumination of the photo-products with 420 nm visible light regenerates the original fluorescence at 420-425 nm. In addition, another fluorescence at 400 nm has also been found in UV (300 nm)-irradiated blue-fluorescent α-crystallin, when exposed to 365 nm-UV light. (author)

  8. Blue Light Enhances Bacterial Clearance and Reduces Organ Injury During Sepsis.

    Science.gov (United States)

    Lewis, Anthony J; Zhang, Xianghong; Griepentrog, John E; Yuan, Du; Collage, Richard D; Waltz, Paul K; Angus, Derek C; Zuckerbraun, Brian S; Rosengart, Matthew R

    2018-05-04

    The physiology of nearly all mammalian organisms are entrained by light and exhibit circadian rhythm. The data derived from animal studies show that light influences immunity, and these neurophysiologic pathways are maximally entrained by the blue spectrum. Here, we hypothesize that bright blue light reduces acute kidney injury by comparison with either bright red or standard, white fluorescent light in mice subjected to sepsis. To further translational relevance, we performed a pilot clinical trial of blue light therapy in human subjects with appendicitis. Laboratory animal research, pilot human feasibility trial. University basic science laboratory and tertiary care hospital. Male C57BL/6J mice, adult (> 17 yr) patients with acute appendicitis. Mice underwent cecal ligation and puncture and were randomly assigned to a 24-hour photoperiod of bright blue, bright red, or ambient white fluorescent light. Subjects with appendicitis were randomized to receive postoperatively standard care or standard care plus high-illuminance blue light. Exposure to bright blue light enhanced bacterial clearance from the peritoneum, reduced bacteremia and systemic inflammation, and attenuated the degree of acute kidney injury. The mechanism involved an elevation in cholinergic tone that augmented tissue expression of the nuclear orphan receptor REV-ERBα and occurred independent of alterations in melatonin or corticosterone concentrations. Clinically, exposure to blue light after appendectomy was feasible and reduced serum interleukin-6 and interleukin-10 concentrations. Modifying the spectrum of light may offer therapeutic utility in sepsis.

  9. Movements of blue rockfish (Sebastes mystinus off central California with comparisons to similar species.

    Directory of Open Access Journals (Sweden)

    Kristen M Green

    Full Text Available Olive (Sebastes serranoides, black (Sebastes melanops, and blue rockfish (Sebastes mystinus are all common inhabitants of nearshore ecosystems on the West coast of North America and important components of the recreational fishery off California. Acoustic monitoring studies indicate that olive rockfish are highly residential and that black rockfish are capable of long migrations and have less site fidelity; yet little is known about the long-term movements of blue rockfish. External tag-recapture studies indicate that blue rockfish may have intermediate movements relative to these congener nearshore species. To better understand the site fidelity, and daily and seasonal movements of blue rockfish over long (>1-year time scales, we placed acoustic transmitters into 21 adult blue rockfish (30-41 cm total length in Carmel Bay, California. Blue rockfish displayed intermediate movement patterns and residency relative to other similar kelp forest rockfish species. Two-thirds of tagged blue rockfish (13 fish exhibited high residency to the study area (>12 mo. When in residence, mean home range of blue rockfish was 0.23 km2, however as many as 30% of tagged blue rockfish shifted their core home range area during the study. Most shifts in home range occurred during upwelling season, and tagged fish moved up to 3.1 km when in residence. Blue rockfish with short residence times were last detected in the study area in late winter and early spring. Blue rockfish were observed at shallower depths during day than night, likely indicative of diurnal feeding. However, over longer time scales, blue rockfish were detected at deeper depths during upwelling periods and with increased wave heights. Daily and seasonal vertical movements of blue rockfish may be influenced by upwelling conditions and local prey abundance.

  10. Blue-shifted photoluminescence of Alq3 dispersed in PMMA

    Indian Academy of Sciences (India)

    Administrator

    Abstract. Alq3 is known to emit bright green light under UV excitation. Blue shift of the emission was reported in recent literature. This was ascribed to the presence of various isomers/crystallographic modifica- tions obtained through train sublimation. Here a blue shift was reported for Alq3 dispersed in PMMA. No iso-.

  11. No effect of blue on winning contests in judo

    NARCIS (Netherlands)

    Dijkstra, Peter D.; Preenen, Paul T. Y.

    2008-01-01

    A study by Rowe et al. reported a winning bias for judo athletes wearing a blue outfit relative to those wearing a white one during the 2004 Olympics. It was suggested that blue is associated with a higher likelihood of winning through differential effects of colour on opponent visibility and/or an

  12. Spatial and temporal occurrence of blue whales off the U.S. West Coast, with implications for management.

    Directory of Open Access Journals (Sweden)

    Ladd M Irvine

    Full Text Available Mortality and injuries caused by ship strikes in U.S. waters are a cause of concern for the endangered population of blue whales (Balaenoptera musculus occupying the eastern North Pacific. We sought to determine which areas along the U.S. West Coast are most important to blue whales and whether those areas change inter-annually. Argos-monitored satellite tags were attached to 171 blue whales off California during summer/early fall from 1993 to 2008. We analyzed portions of the tracks that occurred within U.S. Exclusive Economic Zone waters and defined the 'home range' (HR and 'core areas' (CAU as the 90% and 50% fixed kernel density distributions, respectively, for each whale. We used the number of overlapping individual HRs and CAUs to identify areas of highest use. Individual HR and CAU sizes varied dramatically, but without significant inter-annual variation despite covering years with El Niño and La Niña conditions. Observed within-year differences in HR size may represent different foraging strategies for individuals. The main areas of HR and CAU overlap among whales were near highly productive, strong upwelling centers that were crossed by commercial shipping lanes. Tagged whales generally departed U.S. Exclusive Economic Zone waters from mid-October to mid-November, with high variability among individuals. One 504-d track allowed HR and CAU comparisons for the same individual across two years, showing similar seasonal timing, and strong site fidelity. Our analysis showed how satellite-tagged blue whales seasonally used waters off the U.S. West Coast, including high-risk areas. We suggest possible modifications to existing shipping lanes to reduce the likelihood of collisions with vessels.

  13. Blue emitting KSCN:xCe phosphor for solid state lighting

    Energy Technology Data Exchange (ETDEWEB)

    Chikte, Devayani, E-mail: devi.awade@gmail.com [G.N. Khalsa College, Matunga, Mumbai 400019 (India); Omanwar, S.K. [Department of Physics, S.G.B. Amravati University, Amravati (India); Moharil, S.V. [Department of Physics, R.T.M. Nagpur University, Nagpur 440010 (India)

    2014-01-15

    The intense blue emitting phosphor KSCN:xCe (x=0.005, 0.01, 0.02, 0.04) is synthesized by a simple, time saving, economical method of re-crystallization through aqueous solution at 353 K. Photoluminescence measurements showed that the said phosphor exhibits emission with good intensity peaking at 450 nm corresponding to d→f transitions of Ce{sup 3+} ion. The excitation spectra monitored at 450 nm shows small peak at 282 nm and broad intense excitation band peaking at 350 nm. The latter lies in near ultraviolet (350–410 nm) emission of UV LED. The phosphor KSCN:0.02Ce{sup 3+} shows CIE 1931 color coordinates as (0.1484, 0.0602) whereas the commercial blue phosphor BAM:Eu{sup 2+} shows the color co-ordinates as (0.1417, 0.1072), respectively, indicating better color purity for KSCN: 0.02Ce{sup 3+} compared to the BAM:Eu{sup 2+} phosphor. The color coordinates of KSCN: 0.02Ce{sup 3+} phosphor (0.1484, 0.0602) are nearer to the color coordinate for blue color suggested by the color systems EBUPAL/SECAM, sRGB Blue as well as Adobe blue(0.15, 0.06). -- Highlights: • Novel phosphor KSCN:xCe prepared for the first time. • Method is simple, time saving, economical, easy to handle. • Intense, blue, Characteristic Ce{sup 3+} emission at 450 nm. • nUV excitation, suitable for solid state lighting.

  14. Blue light emitting diodes for optical stimulation of quartz in retrospective dosimetry and dating

    DEFF Research Database (Denmark)

    Bøtter-Jensen, L.; Duller, G.A.T.; Murray, A.S.

    1999-01-01

    Recently developed blue light emitting diodes (LEDs) for the optical stimulation of quartz for use in routine optically stimulated luminescence (OSL) dating and retrospective dosimetry have been tested. For similar power densities, it was found that the higher energy light provided by the blue LE......, preliminary results from ramping the blue light power output with time are demonstrated. It is shown that this technique enables the separation of OSL components with differing stimulation rates.......Recently developed blue light emitting diodes (LEDs) for the optical stimulation of quartz for use in routine optically stimulated luminescence (OSL) dating and retrospective dosimetry have been tested. For similar power densities, it was found that the higher energy light provided by the blue LEDs...... (470 nm) gives order of magnitude greater rate of stimulation in quartz than that from conventional blue-green light filtered from a halogen lamp. A practical blue LED OSL configuration is described. From comparisons of OSL decay curves produced by green and blue light sources, and by examination...

  15. Proteomics meets blue biotechnology: a wealth of novelties and opportunities.

    Science.gov (United States)

    Hartmann, Erica M; Durighello, Emie; Pible, Olivier; Nogales, Balbina; Beltrametti, Fabrizio; Bosch, Rafael; Christie-Oleza, Joseph A; Armengaud, Jean

    2014-10-01

    Blue biotechnology, in which aquatic environments provide the inspiration for various products such as food additives, aquaculture, biosensors, green chemistry, bioenergy, and pharmaceuticals, holds enormous promise. Large-scale efforts to sequence aquatic genomes and metagenomes, as well as campaigns to isolate new organisms and culture-based screenings, are helping to push the boundaries of known organisms. Mass spectrometry-based proteomics can complement 16S gene sequencing in the effort to discover new organisms of potential relevance to blue biotechnology by facilitating the rapid screening of microbial isolates and by providing in depth profiles of the proteomes and metaproteomes of marine organisms, both model cultivable isolates and, more recently, exotic non-cultivable species and communities. Proteomics has already contributed to blue biotechnology by identifying aquatic proteins with potential applications to food fermentation, the textile industry, and biomedical drug development. In this review, we discuss historical developments in blue biotechnology, the current limitations to the known marine biosphere, and the ways in which mass spectrometry can expand that knowledge. We further speculate about directions that research in blue biotechnology will take given current and near-future technological advancements in mass spectrometry. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Green synthesis of silver nanoparticle-reduced graphene oxide using Psidium guajava and its application in SERS for the detection of methylene blue

    Science.gov (United States)

    Chettri, Prajwal; Vendamani, V. S.; Tripathi, Ajay; Singh, Manish Kumar; Pathak, Anand P.; Tiwari, Archana

    2017-06-01

    Here we present the synthesis of reduced graphene oxide and silver nanoparticle-reduced graphene oxide composites using aqueous extract of dry leaves of Psidium guajava by one pot reflux method. Psidium guajava extract simultaneously reduces silver nitrate and graphene oxide in the reaction mixture which is confirmed by various spectroscopic techniques. Variable concentrations of silver nitrate solution are used to obtain reduced graphene oxide with different dosage of silver nanoparticles and the resultant composites are examined using surface enhanced Raman scattering measurements. Considering methylene blue as a probe molecule, it is found that the surface enhanced Raman scattering activity increases with the increase in the dose of silver nanoparticles. Our as-synthesised silver nanoparticle-reduced graphene oxide composite shows remarkable performance in detecting methylene blue with concentration as low as 10-8 M for which the enhancement factor is 4.6 × 105. In addition, we report that the reduced graphene oxide quenches the photoluminescence of methylene blue more efficiently than silver nanoparticle-reduced graphene oxide composite. The charge transfer states have been extracted which are mainly responsible for the quenching processes.

  17. Integrated mangrove-shrimp cultivation: Potential for blue carbon sequestration.

    Science.gov (United States)

    Ahmed, Nesar; Thompson, Shirley; Glaser, Marion

    2018-05-01

    Globally, shrimp farming has had devastating effects on mangrove forests. However, mangroves are the most carbon-rich forests, with blue carbon (i.e., carbon in coastal and marine ecosystems) emissions seriously augmented due to devastating effects on mangrove forests. Nevertheless, integrated mangrove-shrimp cultivation has emerged as a part of the potential solution to blue carbon emissions. Integrated mangrove-shrimp farming is also known as organic aquaculture if deforested mangrove area does not exceed 50% of the total farm area. Mangrove destruction is not permitted in organic aquaculture and the former mangrove area in parts of the shrimp farm shall be reforested to at least 50% during a period of maximum 5 years according to Naturland organic aquaculture standards. This article reviews integrated mangrove-shrimp cultivation that can help to sequester blue carbon through mangrove restoration, which can be an option for climate change mitigation. However, the adoption of integrated mangrove-shrimp cultivation could face several challenges that need to be addressed in order to realize substantial benefits from blue carbon sequestration.

  18. Current distribution and population size of the Blue Swallow Hirundo ...

    African Journals Online (AJOL)

    , the crops, natural pastures, livestock and their dung possibly provide the food source for the aerial arthropods on which the Blue Swallows feed. In total, 151 Blue Swallows were recorded consisting of 62 males, 68 females and 21 unsexed ...

  19. Cyclometalated Iridium(III) Carbene Phosphors for Highly Efficient Blue Organic Light-Emitting Diodes.

    Science.gov (United States)

    Chen, Zhao; Wang, Liqi; Su, Sikai; Zheng, Xingyu; Zhu, Nianyong; Ho, Cheuk-Lam; Chen, Shuming; Wong, Wai-Yeung

    2017-11-22

    Five deep blue carbene-based iridium(III) phosphors were synthesized and characterized. Interestingly, one of them can be fabricated into deep blue, sky blue and white organic light-emitting diodes (OLEDs) through changing the host materials and exciton blocking layers. These deep and sky blue devices exhibit Commission Internationale de l'Éclairage (CIE) coordinates of (0.145, 0.186) and (0.152, 0.277) with external quantum efficiency (EQE) of 15.2% and 9.6%, respectively. The EQE of the deep blue device can be further improved up to 19.0% by choosing a host with suitable energy level of its lowest unoccupied molecular orbital (LUMO).

  20. Clinical and histological effects of blue light on normal skin.

    NARCIS (Netherlands)

    Kleinpenning, M.M.; Smits, T.; Frunt, M.H.A.; Erp, P.E.J. van; Kerkhof, P.C.M. van de; Gerritsen, R.M.

    2010-01-01

    INTRODUCTION: Phototherapy with visible light is gaining interest in dermatological practice. Theoretically, blue light could induce biological effects comparable to ultraviolet A (UVA) radiation. OBJECTIVES: To study the effects of blue light on normal skin in terms of photodamage, skin ageing and

  1. [The dangers of blue light: True story!].

    Science.gov (United States)

    Renard, G; Leid, J

    2016-05-01

    The dangers of the blue light are the object of numerous publications, for both the scientific community and the general public. The new prolific development of light sources emitting potentially toxic blue light (415-455nm) ranges from LED (Light Emitting Diodes) lamps for interior lighting to television screens, computers, digital tablets and smartphones using OLED (Organic Light Emitting Diode) or AMOLED (Active-Matrix Organic Light Emitting Diode) technology. First we will review some technical terms and the main characteristics of light perceived by the human eye. Then we will discuss scientific proof of the toxicity of blue light to the eye, which may cause cataract or macular degeneration. Analysis of the light spectra of several light sources, from natural light to LED lamps, will allow us to specify even better the dangers related to each light source. LED lamps, whether used as components for interior lighting or screens, are of concern if they are used for extended viewing times and at short distance. While we can protect ourselves from natural blue light by wearing colored glasses which filter out, on both front and back surfaces, the toxic wavelengths, it is more difficult to protect oneself from LED lamps in internal lighting, the use of which should be restricted to "white warmth" lamps (2700K). As far as OLED or AMOLED screens are concerned, the only effective protection consists of using them occasionally and only for a short period of time. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  2. The Physics of the Blues

    Science.gov (United States)

    Gibson, J. Murray

    2009-03-01

    In looking at the commonalities between music and science, one sees that the musician's palette is based on the principles of physics. The pitch of a musical note is determined by the frequency of the sound wave. The scales that musicians use to create and play music can be viewed as a set of rules. What makes music interesting is how musicians develop those rules and create ambiguity with them. I will discuss the evolution of western musical scales in this context. As a particular example, ``Blue'' notes are very harmonic notes that are missing from the equal temperament scale. The techniques of piano blues and jazz represent the melding of African and Western music into something totally new and exciting. Live keyboard demonstrations will be used. Beyond any redeeming entertainment value the talk will emphasize the serious connections between science and art in music. Nevertheless tips will be accepted.

  3. Code Blue Emergencies: A Team Task Analysis and Educational Initiative.

    Science.gov (United States)

    Price, James W; Applegarth, Oliver; Vu, Mark; Price, John R

    2012-01-01

    The objective of this study was to identify factors that have a positive or negative influence on resuscitation team performance during emergencies in the operating room (OR) and post-operative recovery unit (PAR) at a major Canadian teaching hospital. This information was then used to implement a team training program for code blue emergencies. In 2009/10, all OR and PAR nurses and 19 anesthesiologists at Vancouver General Hospital (VGH) were invited to complete an anonymous, 10 minute written questionnaire regarding their code blue experience. Survey questions were devised by 10 recovery room and operation room nurses as well as 5 anesthesiologists representing 4 different hospitals in British Columbia. Three iterations of the survey were reviewed by a pilot group of nurses and anesthesiologists and their feedback was integrated into the final version of the survey. Both nursing staff (n = 49) and anesthesiologists (n = 19) supported code blue training and believed that team training would improve patient outcome. Nurses noted that it was often difficult to identify the leader of the resuscitation team. Both nursing staff and anesthesiologists strongly agreed that too many people attending the code blue with no assigned role hindered team performance. Identifiable leadership and clear communication of roles were identified as keys to resuscitation team functioning. Decreasing the number of people attending code blue emergencies with no specific role, increased access to mock code blue training, and debriefing after crises were all identified as areas requiring improvement. Initial team training exercises have been well received by staff.

  4. Code Blue Emergencies: A Team Task Analysis and Educational Initiative

    Directory of Open Access Journals (Sweden)

    James W. Price

    2012-04-01

    Full Text Available Introduction: The objective of this study was to identify factors that have a positive or negative influence on resuscitation team performance during emergencies in the operating room (OR and post-operative recovery unit (PAR at a major Canadian teaching hospital. This information was then used to implement a team training program for code blue emergencies. Methods: In 2009/10, all OR and PAR nurses and 19 anesthesiologists at Vancouver General Hospital (VGH were invited to complete an anonymous, 10 minute written questionnaire regarding their code blue experience. Survey questions were devised by 10 recovery room and operation room nurses as well as 5 anesthesiologists representing 4 different hospitals in British Columbia. Three iterations of the survey were reviewed by a pilot group of nurses and anesthesiologists and their feedback was integrated into the final version of the survey. Results: Both nursing staff (n = 49 and anesthesiologists (n = 19 supported code blue training and believed that team training would improve patient outcome. Nurses noted that it was often difficult to identify the leader of the resuscitation team. Both nursing staff and anesthesiologists strongly agreed that too many people attending the code blue with no assigned role hindered team performance. Conclusion: Identifiable leadership and clear communication of roles were identified as keys to resuscitation team functioning. Decreasing the number of people attending code blue emergencies with no specific role, increased access to mock code blue training, and debriefing after crises were all identified as areas requiring improvement. Initial team training exercises have been well received by staff.

  5. Temporal dynamics of blue and green virtual water trade networks

    Science.gov (United States)

    Konar, M.; Dalin, C.; Hanasaki, N.; Rinaldo, A.; Rodriguez-Iturbe, I.

    2012-12-01

    Global food security increasingly relies on the trade of food commodities. Freshwater resources are essential to agricultural production and are thus embodied in the trade of food commodities, referred to as "virtual water trade." Agricultural production predominantly relies on rainwater (i.e., "green water"), though irrigation (i.e., "blue water") does play an important role. These different sources of water have distinctly different opportunity costs, which may be reflected in the way these resources are traded. Thus, the temporal dynamics of the virtual water trade networks from these distinct water sources require characterization. We find that 42 × 109 m3 blue and 310 × 109 m3 green water was traded in 1986, growing to 78 × 109 m3 blue and 594 × 109 m3 green water traded in 2008. Three nations dominate the export of green water resources: the USA, Argentina, and Brazil. As a country increases its export trade partners it tends to export relatively more blue water. However, as a country increases its import trade partners it does not preferentially import water from a specific source. The amount of virtual water that a country imports by increasing its import trade partners has been decreasing over time, with the exception of the soy trade. Both blue and green virtual water networks are efficient: 119 × 109 m3 blue and 105 × 109 m3 green water were saved in 2008. Importantly, trade has been increasingly saving water over time, due to the intensification of crop trade on more water-efficient links.

  6. Blue ocean leadership.

    Science.gov (United States)

    Kim, W Chan; Mauborgne, Renée

    2014-05-01

    Ten years ago, two INSEAD professors broke ground by introducing "blue ocean strategy," a new model for discovering uncontested markets that are ripe for growth. In this article, they apply their concepts and tools to what is perhaps the greatest challenge of leadership: closing the gulf between the potential and the realized talent and energy of employees. Research indicates that this gulf is vast: According to Gallup, 70% of workers are disengaged from their jobs. If companies could find a way to convert them into engaged employees, the results could be transformative. The trouble is, managers lack a clear understanding of what changes they could make to bring out the best in everyone. Here, Kim and Mauborgne offer a solution to that problem: a systematic approach to uncovering, at each level of the organization, which leadership acts and activities will inspire employees to give their all, and a process for getting managers throughout the company to start doing them. Blue ocean leadership works because the managers' "customers"-that is, the people managers oversee and report to-are involved in identifying what's effective and what isn't. Moreover, the approach doesn't require leaders to alter who they are, just to undertake a different set of tasks. And that kind of change is much easier to implement and track than changes to values and mind-sets.

  7. Removing the Influence of Shimmer in the Calculation of Harmonics-To-Noise Ratios Using Ensemble-Averages in Voice Signals

    OpenAIRE

    Carlos Ferrer; Eduardo González; María E. Hernández-Díaz; Diana Torres; Anesto del Toro

    2009-01-01

    Harmonics-to-noise ratios (HNRs) are affected by general aperiodicity in voiced speech signals. To specifically reflect a signal-to-additive-noise ratio, the measurement should be insensitive to other periodicity perturbations, like jitter, shimmer, and waveform variability. The ensemble averaging technique is a time-domain method which has been gradually refined in terms of its sensitivity to jitter and waveform variability and required number of pulses. In this paper, shimmer is introduced ...

  8. Designing green and blue infrastructure to support healthy urban living

    NARCIS (Netherlands)

    Gehrels, H.; Meulen, van der Suzanne; Schasfoort, F.; Bosch, Peter; Brolsma, R.; Dinther, van D.; Geerling, G.J.; Goossens, M.; Jacobs, C.M.J.; jong, de Merijn; Kok, Sien; Massop, H.T.L.

    2016-01-01

    This report focuses on developing concepts and design principles for blue and green infrastructure that not only support climate resilience but also contribute to a healthy and liveable urban environment. We will first assess the effectiveness of blue and green infrastructure on the basis of

  9. The Biology of blue-green algae

    National Research Council Canada - National Science Library

    Carr, Nicholas G; Whitton, B. A

    1973-01-01

    .... Their important environmental roles, their part in nitrogen fixation and the biochemistry of phototrophic metabolism are some of the attractions of blue-geen algae to an increasing number of biologists...

  10. Combatant eye protection: an introduction to the blue light hazard

    Science.gov (United States)

    Lattimore, Morris R.

    2016-05-01

    Emerging evidence of metabolic vulnerability to visible blue light is vitally important, as it is indicative of a scalable threshold effect. Added stressors (e.g., increased altitude or contact lens wear) could shift the wavelength effects toward a more damaging clinical picture. Recent reports have indicated rod photo-pigment damage resulting from solar blue-light exposures, adversely affecting unaided night vision, a militarily important performance decrement. The activation wavelength for the daily synchronous setting of the Circadian Clock, which regulates the synchronization of all hormonal and organ systems throughout the body, falls within this blue light perceptual range.

  11. Sustainable and efficient allocation of limited blue and green water resources

    OpenAIRE

    Schyns, Joseph Franciscus

    2018-01-01

    Freshwater stems from precipitation over land, which differentiates into a blue water flow (groundwater and surface water) and a green water flow (evaporation). Both flows are partially allocated to serve the economy, resulting in blue and green water footprints (WF). There are maximum sustainable levels to the blue and green WF, since rainfall is limited and part of the flows need to be reserved for aquatic and terrestrial biodiversity. Water scarcity, the degree to which the actual approach...

  12. Microscopic origin of the optical processes in blue sapphire.

    Science.gov (United States)

    Bristow, Jessica K; Parker, Stephen C; Catlow, C Richard A; Woodley, Scott M; Walsh, Aron

    2013-06-11

    Al2O3 changes from transparent to a range of intense colours depending on the chemical impurities present. In blue sapphire, Fe and Ti are incorporated; however, the chemical process that gives rise to the colour has long been debated. Atomistic modelling identifies charge transfer from Ti(III) to Fe(III) as being responsible for the characteristic blue appearance.

  13. Microscopic origin of the optical processes in blue sapphire

    OpenAIRE

    Bristow, JK; Parker, SC; Catlow, CRA; Woodley, SM; Walsh, A

    2013-01-01

    Al2O3 changes from transparent to a range of intense colours depending on the chemical impurities present. In blue sapphire, Fe and Ti are incorporated; however, the chemical process that gives rise to the colour has long been debated. Atomistic modelling identifies charge transfer from Ti(III) to Fe(III) as being responsible for the characteristic blue appearance.

  14. BlueSky Cloud Framework: An E-Learning Framework Embracing Cloud Computing

    Science.gov (United States)

    Dong, Bo; Zheng, Qinghua; Qiao, Mu; Shu, Jian; Yang, Jie

    Currently, E-Learning has grown into a widely accepted way of learning. With the huge growth of users, services, education contents and resources, E-Learning systems are facing challenges of optimizing resource allocations, dealing with dynamic concurrency demands, handling rapid storage growth requirements and cost controlling. In this paper, an E-Learning framework based on cloud computing is presented, namely BlueSky cloud framework. Particularly, the architecture and core components of BlueSky cloud framework are introduced. In BlueSky cloud framework, physical machines are virtualized, and allocated on demand for E-Learning systems. Moreover, BlueSky cloud framework combines with traditional middleware functions (such as load balancing and data caching) to serve for E-Learning systems as a general architecture. It delivers reliable, scalable and cost-efficient services to E-Learning systems, and E-Learning organizations can establish systems through these services in a simple way. BlueSky cloud framework solves the challenges faced by E-Learning, and improves the performance, availability and scalability of E-Learning systems.

  15. Bedazzled: A Blue and Black Ship, Dressed to Deceive

    Directory of Open Access Journals (Sweden)

    Tim S. Meese

    2015-04-01

    Full Text Available The blue and black dress that “melted the Internet” is thought to have done so because its perceived color depended on people using different prior assumptions about discounting the illuminant. However, this is not the first monochromatic object to have confused the public. For a brief period during WWI, RMS Mauretania was dressed in (dazzle camouflage shades of blue and black/grey, yet she is sometimes depicted by artists, modelers, and historians in a much showier dress of red, blue, yellow, green, and black. I raise the possibility that this originates from a case of public deception deriving from the momentary misperception of a playful artist who neglected to discount the illuminant, propagating the most (perhaps only successful application of dazzle camouflage known.

  16. Perianth bottom-specific blue color development in Tulip cv. Murasakizuisho requires ferric ions.

    Science.gov (United States)

    Shoji, Kazuaki; Miki, Naoko; Nakajima, Noriyuki; Momonoi, Kazumi; Kato, Chiharu; Yoshida, Kumi

    2007-02-01

    The entire flower of Tulipa gesneriana cv. Murasakizuisho is purple, except the bottom, which is blue. To elucidate the mechanism of the different color development in the same petal, we prepared protoplasts from the purple and blue epidermal regions and measured the flavonoid composition by HPLC, the vacuolar pH by a proton-selective microelectrode, and element contents by the inductively coupled plasma (ICP) method. Chemical analyses revealed that the anthocyanin and flavonol compositions in both purple and blue colored protoplasts were the same; delphinidin 3-O-rutinoside (1) and major three flavonol glycosides, manghaslin (2), rutin (3) and mauritianin (4). The vacuolar pH values of the purple and blue protoplasts were 5.5 and 5.6, respectively, without any significant difference. However, the Fe(3+) content in the blue protoplast was approximately 9.5 mM, which was 25 times higher than that in the purple protoplasts. We could reproduce the purple solution by mixing 1 with two equimolar concentrations of flavonol with lambda(vismax) = 539 nm, which was identical to that of the purple protoplasts. Furthermore, addition of Fe(3+) to the mixture of 1-4 gave the blue solution with lambda(vismax) = 615 nm identical to that of the blue protoplasts. We have established that Fe(3+) is essential for blue color development in the tulip.

  17. Prussian Blue decorporation of 137Cs in beagles of different ages

    International Nuclear Information System (INIS)

    Melo, D.R.; Lundgren, D.L.; Muggenburg, B.A.; Guilmette, R.A.

    1996-01-01

    A 6-wk study was conducted using immature (4.7 mo), young adult (2.4 y), and aged (13.5 y) male beagles to determine the modifying effect of age on the effectiveness of Prussian Blue decorporation therapy for the removal of injected 137 Cs. Whole-body clearance rates for injected 137 Cs decreased with increasing age in the dogs. Treatment with Prussian Blue changed the ratio of fecal to urinary 137 Cs excretion from 0.8 in untreated dogs to 2.2 in treated animals. The 137 Cs concentrations in tissues of untreated and Prussian Blue-treated dogs at the end of the 6-wk study were similar, with the greatest concentrations in the skeletal muscle tissue, spleen, and kidneys. There was a lower concentration of 137 Cs in the livers of the treated dogs. The reductions in the average total whole-body doses resulting from Prussian Blue treatment during the course of this study were 51% in the immature, 31% in the young adult, and 38% in the aged dogs. Because of the differences in the intake of Prussian Blue by the dogs in the different groups relative to their body weight, it is unclear as to the relative effectiveness of Prussian Blue in dogs of different ages. 33 refs., 1 fig., 5 tabs

  18. Identifying the optical phenomena responsible for the blue appearance of veins

    Science.gov (United States)

    Van Leeuwen, Spencer R.; Baranoski, Gladimir V. G.

    2017-09-01

    Blue in nature is often associated with beauty. It can be observed all around us, from captivating blue eyes to iridescent blue butterfly wings. While colours in nature are often the result of pigmentation, the majority of natural blue is produced by structural coloration. The colour of the sky, for example, is primarily caused by Rayleigh scattering. In this paper, we examine a single occurrence of blue in nature, specifically the blue appearance of veins near the surface of human skin. The most comprehensive investigation of this coloration to date showed that it arises from a combination of the scattering properties of skin and the absorptance of venous blood. However, that work only considered broad optical properties of these mediums and did not identify the source of the colour. In this paper, we employ in silico experiments, performed using first-principles light interaction models for skin and blood, to investigate the net effect of skin and vein optical properties on their aggregate reflectance across the visible range. We show that the contribution of skin to the distinct appearance of veins primarily results from Rayleigh scattering occurring within the papillary dermis, a sublayer of the skin. The results of this paper, in addition to addressing an old open scientific question, may have practical implications for performing non-invasive measurements of the physiological properties of skin and blood.

  19. Modified methylene blue injection improves lymph node harvest in rectal cancer.

    Science.gov (United States)

    Liu, Jianpei; Huang, Pinjie; Zheng, Zongheng; Chen, Tufeng; Wei, Hongbo

    2017-04-01

    The presence of nodal metastases in rectal cancer plays an important role in accurate staging and prognosis, which depends on adequate lymph node harvest. The aim of this prospective study is to investigate the feasibility and survival benefit of improving lymph node harvest by a modified method with methylene blue injection in rectal cancer specimens. One hundred and thirty-one patients with rectal cancer were randomly assigned to the control group in which lymph nodes were harvested by palpation and sight, or to the methylene blue group using a modified method of injection into the superior rectal artery with methylene blue. Analysis of clinicopathologic records, including a long-term follow-up, was performed. In the methylene blue group, 678 lymph nodes were harvested by simple palpation and sight. Methylene blue injection added 853 lymph nodes to the total harvest as well as 32 additional metastatic lymph nodes, causing a shift to node-positive stage in four patients. The average number of lymph nodes harvested was 11.7 ± 3.4 in the control group and 23.2 ± 4.7 in the methylene blue group, respectively. The harvest of small lymph nodes (rectal cancer, especially small node and metastatic node retrieval, which provided more accurate staging. However, it was not associated with overall survival. © 2014 Royal Australasian College of Surgeons.

  20. Codigestion of Taihu blue algae with swine manure for biogas production

    International Nuclear Information System (INIS)

    Miao, Hengfeng; Wang, Shouquan; Zhao, Mingxing; Huang, Zhenxing; Ren, Hongyan; Yan, Qun; Ruan, Wenquan

    2014-01-01

    Highlights: • Codigestion of blue algae with swine manure has the highest CH 4 yield at ISR 2.0. • pH, TAN, N-NH 3 and VFAs confirmed the appropriate stability of the codigestion. • 35.44% VS reduction was achieved by codigestion of blue algae with swine manure. • Three key enzyme characteristics demonstrated the higher efficiencies of codigestion. - Abstract: Anaerobic digestion (AD) of Taihu blue algae and its codigestion with swine manure was evaluated at different inoculum substrate ratios (ISRs) from 0.5 to 3.0. Results showed that codigestion of blue algae with swine manure led to the highest methane (CH 4 ) production of 212.7 mL g −1 VS at ISR 2.0, while digestion of blue algae inoculated with granular sludge brought out the optimized CH 4 production of 73.5 mL g −1 VS at ISR 3.0. The values of pH, total ammonia nitrogen (TAN), free ammonia nitrogen (N-NH 3 ) and volatile fatty acids (VFAs) showed no significant difference between the digestion and codigestion, confirming the appropriate stability of the two batch anaerobic processes. Closer examination of VS removal rates and key enzymes variation proved codigestion had higher efficiencies in biodegradation and methanation, which demonstrated that AD of blue algae with swine manure was a promising technology for both solid wastes treatment and renewable-energy production

  1. Valuing blue carbon: carbon sequestration benefits provided by the marine protected areas in Colombia.

    Directory of Open Access Journals (Sweden)

    Tatiana G Zarate-Barrera

    Full Text Available Marine protected areas are aimed to protect and conserve key ecosystems for the provision of a number of ecosystem services that are the basis for numerous economic activities. Among the several services that these areas provide, the capacity of sequestering (capturing and storing organic carbon is a regulating service, provided mainly by mangroves and seagrasses, that gains importance as alternatives for mitigating global warming become a priority in the international agenda. The objective of this study is to value the services associated with the capture and storage of oceanic carbon, known as Blue Carbon, provided by a new network of marine protected areas in Colombia. We approach the monetary value associated to these services through the simulation of a hypothetical market for oceanic carbon. To do that, we construct a benefit function that considers the capacity of mangroves and seagrasses for capturing and storing blue carbon, and simulate scenarios for the variation of key variables such as the market carbon price, the discount rate, the natural rate of loss of the ecosystems, and the expectations about the post-Kyoto negotiations. The results indicate that the expected benefits associated to carbon capture and storage provided by these ecosystems are substantial but highly dependent on the expectations in terms of the negotiations surrounding the extension of the Kyoto Protocol and the dynamics of the carbon credit's demand and supply. We also find that the natural loss rate of these ecosystems does not seem to have a significant effect on the annual value of the benefits. This approach constitutes one of the first attempts to value blue carbon as one of the services provided by conservation.

  2. NAMMA MODIS/AQUA AND MODIS/TERRA DEEP BLUE PRODUCTS V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The NAMMA MODIS/AQUA and MODIS/TERRA Deep Blue Products dataset is a collection of images depicting the aerosol optical depth derived from the MODIS deep blue...

  3. Dynamic Blue Light-Inducible T7 RNA Polymerases (Opto-T7RNAPs) for Precise Spatiotemporal Gene Expression Control.

    Science.gov (United States)

    Baumschlager, Armin; Aoki, Stephanie K; Khammash, Mustafa

    2017-11-17

    Light has emerged as a control input for biological systems due to its precise spatiotemporal resolution. The limited toolset for light control in bacteria motivated us to develop a light-inducible transcription system that is independent from cellular regulation through the use of an orthogonal RNA polymerase. Here, we present our engineered blue light-responsive T7 RNA polymerases (Opto-T7RNAPs) that show properties such as low leakiness of gene expression in the dark state, high expression strength when induced with blue light, and an inducible range of more than 300-fold. Following optimization of the system to reduce expression variability, we created a variant that returns to the inactive dark state within minutes once the blue light is turned off. This allows for precise dynamic control of gene expression, which is a key aspect for most applications using optogenetic regulation. The regulators, which only require blue light from ordinary light-emitting diodes for induction, were developed and tested in the bacterium Escherichia coli, which is a crucial cell factory for biotechnology due to its fast and inexpensive cultivation and well understood physiology and genetics. Opto-T7RNAP, with minor alterations, should be extendable to other bacterial species as well as eukaryotes such as mammalian cells and yeast in which the T7 RNA polymerase and the light-inducible Vivid regulator have been shown to be functional. We anticipate that our approach will expand the applicability of using light as an inducer for gene expression independent from cellular regulation and allow for a more reliable dynamic control of synthetic and natural gene networks.

  4. Evolution of a blue supergiant with a neutron star companion immersed in its envelope

    International Nuclear Information System (INIS)

    Delgado, A.J.

    1980-01-01

    The evolution of a binary system consisting of 1 Msub(sun) neutron star and a 25 Msub(sun) blue supergiant through a phase of common envelope is investigated. We include the effects of an additional energy source on the supergiant's envelope, due to the presence of the neutron star, and variable mass loss from the system, taken as proportional to the total luminosity. The results indicate that, independently of the initial period, the system loses its whole envelope as a consequence of the common envelope phase, the final product of this being a detached system, consisting of a neutron star and a helium star. (orig.)

  5. Analysis and modification of blue sapphires from Rwanda by ion beam techniques

    International Nuclear Information System (INIS)

    Bootkul, D.; Chaiwai, C.; Tippawan, U.; Wanthanachaisaeng, B.; Intarasiri, S.

    2015-01-01

    Highlights: • Ion beam analysis is an effective method for detecting trace elements. • Ion beam treatment is able to improve optical and color appearances of the blue sapphire from Rwanda. • These alternative methods can be extended to jewelry industry for large scale application. - Abstract: Blue sapphire is categorised in a corundum (Al_2O_3) group. The gems of this group are always amazed by their beauties and thus having high value. In this study, blue sapphires from Rwanda, recently came to Thai gemstone industry, are chosen for investigations. On one hand, we have applied Particle Induced X-ray Emission (PIXE), which is a highly sensitive and precise analytical technique that can be used to identify and quantify trace elements, for chemical analysis of the sapphires. Here we have found that the major element of blue sapphires from Rwanda is Al with trace elements such as Fe, Ti, Cr, Ga and Mg as are commonly found in normal blue sapphire. On the other hand, we have applied low and medium ion implantations for color improvement of the sapphire. It seems that a high amount of energy transferring during cascade collisions have altered the gems properties. We have clearly seen that the blue color of the sapphires have been intensified after nitrogen ion bombardment. In addition, the gems were also having more transparent and luster. The UV–Vis–NIR measurement detected the modification of their absorption properties, implying of the blue color increasing. Here the mechanism of these modifications is postulated and reported. In any point of view, the bombardment by using nitrogen ion beam is a promising technique for quality improvement of the blue sapphire from Rwanda.

  6. Oxidation states of Fe and Ti in blue sapphire

    International Nuclear Information System (INIS)

    Wongrawang, P; Wongkokua, W; Monarumit, N; Thammajak, N; Wathanakul, P

    2016-01-01

    X-ray absorption near-edge spectroscopy (XANES) can be used to study the oxidation state of a dilute system such as transition metal defects in solid-state samples. In blue sapphire, Fe and Ti are defects that cause the blue color. Inter-valence charge transfer (IVCT) between Fe 2+ and Ti 4+ has been proposed to describe the optical color’s origin. However, the existence of divalent iron cations has not been thoroughly investigated. Fluorescent XANES is therefore employed to study K-edge absorptions of Fe and Ti cations in various blue sapphire samples including natural, synthetic, diffused and heat-treated sapphires. All the samples showed an Fe absorption edge at 7124 eV, corresponding to the Fe 3+ state; and Ti at 4984 eV, corresponding to Ti 4+ . From these results, we propose Fe 3+ -Ti 4+ mixed acceptor states located at 1.75 eV and 2.14 eV above the valence band of corundum, that correspond to 710 nm and 580 nm bands of UV–vis absorption spectra, to describe the cause of the color of blue sapphire. (paper)

  7. 77 FR 68117 - Blue Summit Wind, LLC; Notice of Petition for Declaratory Order

    Science.gov (United States)

    2012-11-15

    ... from the Blue Summit's wind energy generator (Blue Summit Facility) located within the Southwest Power... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. EL13-17-000] Blue Summit Wind, LLC; Notice of Petition for Declaratory Order Take notice that on November 6, 2012, pursuant to...

  8. Determination of performance characteristics of scientific applications on IBM Blue Gene/Q

    Energy Technology Data Exchange (ETDEWEB)

    Evangelinos, C. [IBM Research Division, Cambridge, MA (United States); Walkup, R. E. [IBM, Yorktown Heights, NY (United States). Thomas J. Watson Research Center; Sachdeva, V. [IBM Research Division, Cambridge, MA (United States); Jordan, K. E. [IBM Research Division, Cambridge, MA (United States); Gahvari, H. [Univ. of Illinois, Urbana-Champaign, IL (United States). Computer Science Dept.; Chung, I. -H. [IBM, Yorktown Heights, NY (United States). Thomas J. Watson Research Center; Perrone, M. P. [IBM, Yorktown Heights, NY (United States). Thomas J. Watson Research Center; Lu, L. [IBM, Yorktown Heights, NY (United States). Thomas J. Watson Research Center; Liu, L. -K. [IBM, Yorktown Heights, NY (United States). Thomas J. Watson Research Center; Magerlein, K. [IBM, Yorktown Heights, NY (United States). Thomas J. Watson Research Center

    2013-02-13

    The IBM Blue Gene®/Q platform presents scientists and engineers with a rich set of hardware features such as 16 cores per chip sharing a Level 2 cache, a wide SIMD (single-instruction, multiple-data) unit, a five-dimensional torus network, and hardware support for collective operations. Especially important is the feature related to cores that have four “hardware threads,” which makes it possible to hide latencies and obtain a high fraction of the peak issue rate from each core. All of these hardware resources present unique performance-tuning opportunities on Blue Gene/Q. We provide an overview of several important applications and solvers and study them on Blue Gene/Q using performance counters and Message Passing Interface profiles. We also discuss how Blue Gene/Q tools help us understand the interaction of the application with the hardware and software layers and provide guidance for optimization. Furthermore, on the basis of our analysis, we discuss code improvement strategies targeting Blue Gene/Q. Information about how these algorithms map to the Blue Gene® architecture is expected to have an impact on future system design as we move to the exascale era.

  9. Investigation of Blue Bedding in Cages Housing Treatment-Naïve Hamsters.

    Science.gov (United States)

    Shah, Vishal D; Walton, Betsy J; Culp, Amanda G; Castellino, Stephen

    2015-11-01

    During the acclimation phase of a preclinical safety study involving Syrian golden hamsters, some of the cages of treatment-naïve animals were noted to contain blue-tinged bedding; the urine of these hamsters was not discolored. We sought to understand the underlying cause of this unusual finding to ensure that the study animals were healthy and free from factors that might confound the interpretation of the study. Analysis of extracts from the blue bedding by using HPLC with inline UV detection and high-resolution mass spectrometry indicated that the color was due to the presence of indigo blue. Furthermore, the indigo blue likely was formed through a series of biochemical events initiated by the intestinal metabolism of tryptophan to an indoxyl metabolite. We offer 2 hypotheses regarding the fate of the indoxyl metabolite: indigo blue formation through oxidative coupling in the liver or through urinary bacterial metabolism.

  10. Blue Ocean vs. Five Forces

    NARCIS (Netherlands)

    A.E. Burke (Andrew); A.J. van Stel (André); A.R. Thurik (Roy)

    2010-01-01

    textabstractThe article reports on the authors' research in the Netherlands which focused on a profit model in Dutch retail stores and a so-called blue-ocean approach which requires a new market that attracts consumers and increases profits. Topics include the competitive strategy approach to

  11. Adsorption Of Blue-Dye On Activated Carbons Produced From Rice ...

    African Journals Online (AJOL)

    The activated carbons prepared were used for the adsorption of blue-dye of concentration ranging from 100 to 2000 mg/l from aqueous solution. The results obtained indicated that ferric chloride-activated carbons produced from coconut coirpith are better adsorbents for blue-dye than those prepared from rice husk.

  12. Full color camouflage in a printable photonic blue-colored polymer

    NARCIS (Netherlands)

    Moirangthem, M.; Schenning, A.P.H.J.

    2018-01-01

    A blue reflective photonic polymer coating which can be patterned in full color, from blue to red, by printing with an aqueous calcium nitrate solution has been fabricated. Color change in the cholesteric liquid-crystalline polymer network over the entire visible spectrum is obtained by the use of

  13. Optimization of Tapered Photonic Crystal Fibers for Blue-Enhanced Supercontinuum Generation

    DEFF Research Database (Denmark)

    Møller, Uffe; Sørensen, Simon Toft; Larsen, Casper

    2012-01-01

    Tapering of photonic crystal fibers is an effective way of shifting the dispersive wavelength edge of a supercontinuum spectrum down in the deep-blue. We discuss the optimum taper profile for blue-enhanced supercontinuum generation....

  14. Breeding performance of blue tits (Cyanistes cæruleus ultramarinus) in relation to lead pollution and nest failure rates in rural, intermediate, and urban sites in Algeria

    International Nuclear Information System (INIS)

    Brahmia, Zahra; Scheifler, Renaud; Crini, Nadia; Maas, Samuel; Giraudoux, Patrick; Benyacoub, Slim

    2013-01-01

    The breeding parameters and the egg and nestling morphology of Cyanistes caeruleus populations from rural, intermediate, and urban sites in Algeria and the relationships of those variables with lead contamination were studied during three consecutive years. Breeding success was explained only by predation and vandalism rates. Predation was higher in the rural area, whereas vandalism was higher in the urban site. The other measured breeding parameters and egg characteristics were relatively insensitive to study site. The morphology of urban nestlings exhibited a trend toward smaller body size and mass compared to individuals from intermediate and rural sites. Although lead concentrations were higher in the tissues of urban birds than in intermediate and rural individuals, we did not detect a clear influence of this variable on nestling morphology. We conclude that urbanization influenced blue tit breeding parameters through predation and vandalism and nestling morphology through mechanisms other than lead pollution. -- Highlights: ► Life history traits in relation to lead contamination were studied in blue tits from rural, industrial and urban sites. ► The study took place in Annaba, the fourth most populated city of Algeria, during 3 consecutive years. ► Breeding success depended on predation and vandalism, which were high in the rural and urban sites, respectively. ► Urban nestlings exhibited a trend toward smaller body size and mass, which was not explained by lead contamination. ► Urbanization influences breeding success and nestling morphology in blue tits through other mechanisms than lead pollution. -- Urbanization modifies the nestling morphology and breeding success of populations of the Algerian blue tit (Cyanistes caeruleus ultramarinus) through mechanisms other than lead pollution

  15. Chromatic summation and receptive field properties of blue-on and blue-off cells in marmoset lateral geniculate nucleus.

    Science.gov (United States)

    Eiber, C D; Pietersen, A N J; Zeater, N; Solomon, S G; Martin, P R

    2017-11-22

    The "blue-on" and "blue-off" receptive fields in retina and dorsal lateral geniculate nucleus (LGN) of diurnal primates combine signals from short-wavelength sensitive (S) cone photoreceptors with signals from medium/long wavelength sensitive (ML) photoreceptors. Three questions about this combination remain unresolved. Firstly, is the combination of S and ML signals in these cells linear or non-linear? Secondly, how does the timing of S and ML inputs to these cells influence their responses? Thirdly, is there spatial antagonism within S and ML subunits of the receptive field of these cells? We measured contrast sensitivity and spatial frequency tuning for four types of drifting sine gratings: S cone isolating, ML cone isolating, achromatic (S + ML), and counterphase chromatic (S - ML), in extracellular recordings from LGN of marmoset monkeys. We found that responses to stimuli which modulate both S and ML cones are well predicted by a linear sum of S and ML signals, followed by a saturating contrast-response relation. Differences in sensitivity and timing (i.e. vector combination) between S and ML inputs are needed to explain the amplitude and phase of responses to achromatic (S + ML) and counterphase chromatic (S - ML) stimuli. Best-fit spatial receptive fields for S and/or ML subunits in most cells (>80%) required antagonistic surrounds, usually in the S subunit. The surrounds were however generally weak and had little influence on spatial tuning. The sensitivity and size of S and ML subunits were correlated on a cell-by-cell basis, adding to evidence that blue-on and blue-off receptive fields are specialised to signal chromatic but not spatial contrast. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Topology of tiling spaces

    CERN Document Server

    Sadun, Lorenzo

    2008-01-01

    Aperiodic tilings are interesting to mathematicians and scientists for both theoretical and practical reasons. The serious study of aperiodic tilings began as a solution to a problem in logic. Simpler aperiodic tilings eventually revealed hidden "symmetries" that were previously considered impossible, while the tilings themselves were quite striking. The discovery of quasicrystals showed that such aperiodicity actually occurs in nature and led to advances in materials science. Many properties of aperiodic tilings can be discerned by studying one tiling at a time. However, by studying families of tilings, further properties are revealed. This broader study naturally leads to the topology of tiling spaces. This book is an introduction to the topology of tiling spaces, with a target audience of graduate students who wish to learn about the interface of topology with aperiodic order. It isn't a comprehensive and cross-referenced tome about everything having to do with tilings, which would be too big, too hard to ...

  17. Spatial variability of oceanic phycoerythrin spectral types derived from airborne laser-induced fluorescence emissions

    Science.gov (United States)

    Hoge, Frank E.; Wright, C. Wayne; Kana, Todd M.; Swift, Robert N.; Yungel, James K.

    1998-07-01

    We report spatial variability of oceanic phycoerythrin spectral types detected by means of a blue spectral shift in airborne laser-induced fluorescence emission. The blue shift of the phycoerythrobilin fluorescence is known from laboratory studies to be induced by phycourobilin chromophore substitution at phycoerythrobilin chromophore sites in some strains of phycoerythrin-containing marine cyanobacteria. The airborne 532-nm laser-induced phycoerythrin fluorescence of the upper oceanic volume showed distinct segregation of cyanobacterial chromophore types in a flight transect from coastal water to the Sargasso Sea in the western North Atlantic. High phycourobilin levels were restricted to the oceanic (oligotrophic) end of the flight transect, in agreement with historical ship findings. These remotely observed phycoerythrin spectral fluorescence shifts have the potential to permit rapid, wide-area studies of the spatial variability of spectrally distinct cyanobacteria, especially across interfacial regions of coastal and oceanic water masses. Airborne laser-induced phytoplankton spectral fluorescence observations also further the development of satellite algorithms for passive detection of phytoplankton pigments. Optical modifications to the NASA Airborne Oceanographic Lidar are briefly described that permitted observation of the fluorescence spectral shifts.

  18. Analysis and modification of blue sapphires from Rwanda by ion beam techniques

    Science.gov (United States)

    Bootkul, D.; Chaiwai, C.; Tippawan, U.; Wanthanachaisaeng, B.; Intarasiri, S.

    2015-12-01

    Blue sapphire is categorised in a corundum (Al2O3) group. The gems of this group are always amazed by their beauties and thus having high value. In this study, blue sapphires from Rwanda, recently came to Thai gemstone industry, are chosen for investigations. On one hand, we have applied Particle Induced X-ray Emission (PIXE), which is a highly sensitive and precise analytical technique that can be used to identify and quantify trace elements, for chemical analysis of the sapphires. Here we have found that the major element of blue sapphires from Rwanda is Al with trace elements such as Fe, Ti, Cr, Ga and Mg as are commonly found in normal blue sapphire. On the other hand, we have applied low and medium ion implantations for color improvement of the sapphire. It seems that a high amount of energy transferring during cascade collisions have altered the gems properties. We have clearly seen that the blue color of the sapphires have been intensified after nitrogen ion bombardment. In addition, the gems were also having more transparent and luster. The UV-Vis-NIR measurement detected the modification of their absorption properties, implying of the blue color increasing. Here the mechanism of these modifications is postulated and reported. In any point of view, the bombardment by using nitrogen ion beam is a promising technique for quality improvement of the blue sapphire from Rwanda.

  19. Nanotubes based on monolayer blue phosphorus

    KAUST Repository

    Montes Muñ oz, Enrique; Schwingenschlö gl, Udo

    2016-01-01

    We demonstrate structural stability of monolayer zigzag and armchair blue phosphorus nanotubes by means of molecular dynamics simulations. The vibrational spectrum and electronic band structure are determined and analyzed as functions of the tube

  20. Prussian blue caged in spongiform adsorbents using diatomite and carbon nanotubes for elimination of cesium

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Baiyang [Graduate School of Environmental Science, Hokkaido University, Sapporo 060-0810 (Japan); Fugetsu, Bunshi, E-mail: hu@ees.hokudai.ac.jp [Graduate School of Environmental Science, Hokkaido University, Sapporo 060-0810 (Japan); Yu, Hongwen [Graduate School of Environmental Science, Hokkaido University, Sapporo 060-0810 (Japan); Abe, Yoshiteru [Kyoei Engineering Corporation, Niigata 959-1961 (Japan)

    2012-05-30

    Highlights: Black-Right-Pointing-Pointer Prussian blue was sealed in cavities of diatomite using carbon nanotubes. Black-Right-Pointing-Pointer The caged Prussian blue after being permanently immobilized in polyurethane spongy showed a 167 mg/g capability for absorbing cesium. Black-Right-Pointing-Pointer Cesium elimination was accomplished by simply adding the Prussian-blue based spongiform adsorbent to radioactive water. - Abstract: We developed a spongiform adsorbent that contains Prussian blue, which showed a high capacity for eliminating cesium. An in situ synthesizing approach was used to synthesize Prussian blue inside diatomite cavities. Highly dispersed carbon nanotubes (CNTs) were used to form CNT networks that coated the diatomite to seal in the Prussian blue particles. These ternary (CNT/diatomite/Prussian-blue) composites were mixed with polyurethane (PU) prepolymers to produce a quaternary (PU/CNT/diatomite/Prussian-blue), spongiform adsorbent with an in situ foaming procedure. Prussian blue was permanently immobilized in the cell walls of the spongiform matrix and preferentially adsorbed cesium with a theoretical capacity of 167 mg/g cesium. Cesium was absorbed primarily by an ion-exchange mechanism, and the absorption was accomplished by self-uptake of radioactive water by the quaternary spongiform adsorbent.

  1. Investigation of phosphorescent blue organic light emitting diodes

    Energy Technology Data Exchange (ETDEWEB)

    Chiu, Chien-Shu [Department of Electrical Engineering and Information Technology, Technical University of Braunschweig (Germany); Siemens AG, CT MM 1, Erlangen (Germany); Krause, Ralf [Department of Materials Science VI, University of Erlangen-Nuernberg (Germany); Siemens AG, CT MM 1, Erlangen (Germany); Kozlowski, Fryderyk; Hunze, Arvid [Siemens AG, CT MM 1, Erlangen (Germany); Kowalsky, Wolfgang [Department of Electrical Engineering and Information Technology, Technical University of Braunschweig (Germany)

    2008-07-01

    Recently, rapid development of phosphorescent materials has significantly improved the efficiency of organic light emitting diodes (OLEDs). By using efficient phosphorescent emitter materials white OLEDs with high power efficiency values could be demonstrated. But especially blue phosphorescent devices, due to stability issues, need to be further investigated und optimized. In this work, blue OLED devices based on the phosphorescent emitter FIrpic were investigated. Single-carrier hole-only as well as electron-only devices were fabricated and characterized to study the impact of charge carriers on device performance.

  2. Environmental blue light prevents stress in the fish Nile tilapia

    Directory of Open Access Journals (Sweden)

    Volpato G.L.

    2001-01-01

    Full Text Available The present study aimed to test the effects of blue, green or white light on the stress response of the Nile tilapia, Oreochromis niloticus (L.. Each color was tested on two groups of isolated adult Nile tilapia (8 replicates each: one being subjected to confinement stress, and the other not (control. A different environmental color was imposed on each compartment by covering the light source with cellophane of the respective color (green or blue; no cellophane was used for white light. The intensity of green, white and blue lights was 250, 590 and 250 lux, respectively. Basal plasma cortisol levels were determined for each fish prior to the experimental procedures. The fish were confined by being displaced toward one side of the aquarium using an opaque partition for 1 h both in the morning and the afternoon of the two consecutive days of the test. At the end of this 48-h period, plasma cortisol levels were measured again. Basal cortisol levels (ng/ml were similar for each group (ANOVA, F(2;42 = 0.77, P = 0.47. Thus, plasma cortisol levels were analyzed in terms of variation from their respective basal level. After confinement, plasma cortisol levels were not increased in fish submitted to a blue light environment. Thus, blue light prevents the confinement-induced cortisol response, an effect not necessarily related to light intensity.

  3. Does Blue Uniform Color Enhance Winning Probability in Judo Contests?

    Directory of Open Access Journals (Sweden)

    Peter D. Dijkstra

    2018-01-01

    Full Text Available The color of an athlete's uniform may have an effect on psychological functioning and consequently bias the chances of winning contests in sport competition. Several studies reported a winning bias for judo athletes wearing a blue outfit relative to those wearing a white outfit. However, we argue there is no winning bias and that previous studies were confounded and based on small and specific data sets. We tested whether blue biases winning in judo using a very extensive judo data set (45,874 contests from all international judo tournaments between 2008 and 2014. In judo, the first called athlete for the fight used to wear the blue judogi but this was changed to the white judogi in 2011. This switch enabled us to compare the win bias before and after this change to isolate the effect of the color of the judogi. We found a significant win bias for the first called athlete, but this effect was not significantly related to the color of the judogi. The lack of a significant win effect of judogi color suggests that blue does not bias winning in judo, and that the blue-white pairing ensures an equal level of play. Our study shows the importance of thoroughly considering alternative explanations and using extensive datasets in color research in sports and psychology.

  4. Does Blue Uniform Color Enhance Winning Probability in Judo Contests?

    Science.gov (United States)

    Dijkstra, Peter D; Preenen, Paul T Y; van Essen, Hans

    2018-01-01

    The color of an athlete's uniform may have an effect on psychological functioning and consequently bias the chances of winning contests in sport competition. Several studies reported a winning bias for judo athletes wearing a blue outfit relative to those wearing a white outfit. However, we argue there is no winning bias and that previous studies were confounded and based on small and specific data sets. We tested whether blue biases winning in judo using a very extensive judo data set (45,874 contests from all international judo tournaments between 2008 and 2014). In judo, the first called athlete for the fight used to wear the blue judogi but this was changed to the white judogi in 2011. This switch enabled us to compare the win bias before and after this change to isolate the effect of the color of the judogi . We found a significant win bias for the first called athlete, but this effect was not significantly related to the color of the judogi . The lack of a significant win effect of judogi color suggests that blue does not bias winning in judo, and that the blue-white pairing ensures an equal level of play. Our study shows the importance of thoroughly considering alternative explanations and using extensive datasets in color research in sports and psychology.

  5. 700 W blue fiber-coupled diode-laser emitting at 450 nm

    Science.gov (United States)

    Balck, A.; Baumann, M.; Malchus, J.; Chacko, R. V.; Marfels, S.; Witte, U.; Dinakaran, D.; Ocylok, S.; Weinbach, M.; Bachert, C.; Kösters, A.; Krause, V.; König, H.; Lell, A.; Stojetz, B.; Löffler, A.; Strauss, U.

    2018-02-01

    A high-power blue laser source was long-awaited for processing materials with low absorption in the near infrared (NIR) spectral range like copper or gold. Due to the huge progress of GaN-based semiconductors, the performance of blue diode-lasers has made a major step forward recently. With the availability of unprecedented power levels at cw-operating blue diode-lasers emitting at 450 nm, it was possible to set up a high-power diode-laser in the blue spectral range to address these conventional laser applications and probably beyond that to establish completely new utilizations for lasers. Within the scope of the research project "BlauLas", funded within the German photonic initiative "EFFILAS" [8] by the German Federal Ministry of Education and Research (BMBF), Laserline in cooperation with OSRAM aims to realize a cw fiber-coupled diode-laser exceeding 1 kW blue laser power. In this paper the conceptual design and experimental results of a 700 W blue fiber-coupled diode-laser are presented. Initially a close look had to be taken on the mounting techniques of the semiconductors to serve the requirements of the GaN laser diodes. Early samples were used for extensive long term tests to investigate degradation processes. With first functional laser-modules we set up fiber-coupled laser-systems for further testing. Besides adaption of well-known optical concepts a main task within the development of the laser system was the selection and examination of suitable materials and assembling in order to minimize degradation and reach adequate lifetimes. We realized R&D blue lasersystems with lifetimes above 5,000 h, which enable first application experiments on processing of various materials as well as experiments on conversion to white-light.

  6. Analysis and modification of blue sapphires from Rwanda by ion beam techniques

    Energy Technology Data Exchange (ETDEWEB)

    Bootkul, D., E-mail: mo_duangkhae@hotmail.com [Department of General Science - Gems & Jewelry, Faculty of Science, Srinakharinwirot University, Bangkok 10110 (Thailand); Chaiwai, C.; Tippawan, U. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Wanthanachaisaeng, B. [Gems Enhancement Research Unit, Faculty of Gems, Burapha University, Chanthaburi Campus, Chanthaburi 22170 (Thailand); Intarasiri, S., E-mail: saweat@gmail.com [Science and Technology Research Institute, Chiang Mai University, Chiang Mai 50200 (Thailand)

    2015-12-15

    Highlights: • Ion beam analysis is an effective method for detecting trace elements. • Ion beam treatment is able to improve optical and color appearances of the blue sapphire from Rwanda. • These alternative methods can be extended to jewelry industry for large scale application. - Abstract: Blue sapphire is categorised in a corundum (Al{sub 2}O{sub 3}) group. The gems of this group are always amazed by their beauties and thus having high value. In this study, blue sapphires from Rwanda, recently came to Thai gemstone industry, are chosen for investigations. On one hand, we have applied Particle Induced X-ray Emission (PIXE), which is a highly sensitive and precise analytical technique that can be used to identify and quantify trace elements, for chemical analysis of the sapphires. Here we have found that the major element of blue sapphires from Rwanda is Al with trace elements such as Fe, Ti, Cr, Ga and Mg as are commonly found in normal blue sapphire. On the other hand, we have applied low and medium ion implantations for color improvement of the sapphire. It seems that a high amount of energy transferring during cascade collisions have altered the gems properties. We have clearly seen that the blue color of the sapphires have been intensified after nitrogen ion bombardment. In addition, the gems were also having more transparent and luster. The UV–Vis–NIR measurement detected the modification of their absorption properties, implying of the blue color increasing. Here the mechanism of these modifications is postulated and reported. In any point of view, the bombardment by using nitrogen ion beam is a promising technique for quality improvement of the blue sapphire from Rwanda.

  7. Bactericidal effect of blue LED light irradiated TiO{sub 2}/Fe{sub 3}O{sub 4} particles on fish pathogen in seawater

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, T.C. [Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, Taiwan (China); Yao, K.S. [Department of Horticulture, National Taitung Junior College, Taiwan (China); Yeh, N. [Mingdao University, Taiwan (China); Chang, C.I. [Aquaculture Division, Fisheries Research Institute, Council of Agriculture, Taiwan (China); Hsu, H.C. [Department of Life Science, Mingdao University, Taiwan (China); Gonzalez, F. [Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, Taiwan (China); Chang, C.Y., E-mail: cyc1136@yahoo.com.tw [Center of General Education, National Taitung Junior College, Taiwan (China)

    2011-05-31

    This study uses blue LED light ({lambda}{sub max} = 475 nm) activated TiO{sub 2}/Fe{sub 3}O{sub 4} particles to evaluate the particles' photocatalytic activity efficiency and bactericidal effects in seawater of variable salinities. Different TiO{sub 2} to Fe{sub 3}O{sub 4} mole ratios have been synthesized using sol-gel method. The synthesized particles contain mainly anatase TiO{sub 2}, Fe{sub 3}O{sub 4} and FeTiO{sub 3}. The study has identified TiO{sub 2}/Fe{sub 3}O{sub 4}'s bactericidal effect to marine fish pathogen (Photobacterium damselae subsp. piscicida BCRC17065) in seawater. The SEM photo reveals the surface destruction in bacteria incubated with blue LED irradiated TiO{sub 2}/Fe{sub 3}O{sub 4}. The result of this study indicates that 1) TiO{sub 2}/Fe{sub 3}O{sub 4} acquires photocatalytic activities in both the freshwater and the seawater via blue LED irradiation, 2) higher photocatalytic activities appear in solutions of higher TiO{sub 2}/Fe{sub 3}O{sub 4} mole ratio, and 3) photocatalytic activity decreases as salinity increases. These results suggest that the energy saving blue LED light is a feasible light source to activate TiO{sub 2}/Fe{sub 3}O{sub 4} photocatalytic activities in both freshwater and seawater.

  8. Compete or Leapfrog: Creating Blue Ocean through Entrepreneurial Orientation

    OpenAIRE

    Arslan Ayub; Muhammad Salman Aslam; Hanan Iftekhar; Adeel Razzaq; Sabiha Hafeez

    2013-01-01

    The study analyzes the role of entrepreneurial orientation with mediating effect of knowledge creation process to creating Blue Ocean in corporate sector in Pakistan There is an increasing competition among companies due to globalization and technological advancements. Thus, it requires a study to measure the multifaceted influence of entrepreneurial orientation on knowledge creation process and Blue Ocean besides the actual paradigm of this terminology. This concept has been well discussed i...

  9. Sickness benefit cuts mainly affect blue-collar workers.

    Science.gov (United States)

    Aaviksoo, E; Kiivet, R-A

    2014-08-01

    To analyse the impact of sick-pay cuts on the use of sickness absence by employees of different socioeconomic groups. In 2009 cuts in sick pay were implemented in reaction to an economic crisis in Estonia. Nationwide health survey data from the years 2004, 2006, 2008, and 2010 were used to evaluate sickness absence among blue-collar and white-collar workers. The dataset comprised 7,449 employees of 20-64 years of age. Difference in prevalence of absentees before and after the reform was assessed using the chi-squared test. Odds ratios (OR) for sickness absence were calculated in a multivariate logistic regression model. After the reform, the proportion of blue-collar workers who had been on sick leave decreased from 51% to 40% (pgender, age, self-rated health, and presence of chronic disease, especially among those with low incomes; in white-collar employees it reached statistical significance only in those with good self-rated health (p=0.033). In a multivariate model the odds of having lower sickness absence were highly significant only in blue-collar employees (OR 0.63; 95% confidence interval 0.51-0.77, p<0.001). The cuts in sickness benefits had a major impact on the use of sickness absence by blue-collar employees with low salaries. This indicates that lower income was a major factor hindering the use of sick leave as these employees are most vulnerable to the loss of income. © 2014 the Nordic Societies of Public Health.

  10. Point process models for spatio-temporal distance sampling data from a large-scale survey of blue whales

    KAUST Repository

    Yuan, Yuan; Bachl, Fabian E.; Lindgren, Finn; Borchers, David L.; Illian, Janine B.; Buckland, Stephen T.; Rue, Haavard; Gerrodette, Tim

    2017-01-01

    Distance sampling is a widely used method for estimating wildlife population abundance. The fact that conventional distance sampling methods are partly design-based constrains the spatial resolution at which animal density can be estimated using these methods. Estimates are usually obtained at survey stratum level. For an endangered species such as the blue whale, it is desirable to estimate density and abundance at a finer spatial scale than stratum. Temporal variation in the spatial structure is also important. We formulate the process generating distance sampling data as a thinned spatial point process and propose model-based inference using a spatial log-Gaussian Cox process. The method adopts a flexible stochastic partial differential equation (SPDE) approach to model spatial structure in density that is not accounted for by explanatory variables, and integrated nested Laplace approximation (INLA) for Bayesian inference. It allows simultaneous fitting of detection and density models and permits prediction of density at an arbitrarily fine scale. We estimate blue whale density in the Eastern Tropical Pacific Ocean from thirteen shipboard surveys conducted over 22 years. We find that higher blue whale density is associated with colder sea surface temperatures in space, and although there is some positive association between density and mean annual temperature, our estimates are consistent with no trend in density across years. Our analysis also indicates that there is substantial spatially structured variation in density that is not explained by available covariates.

  11. Point process models for spatio-temporal distance sampling data from a large-scale survey of blue whales

    KAUST Repository

    Yuan, Yuan

    2017-12-28

    Distance sampling is a widely used method for estimating wildlife population abundance. The fact that conventional distance sampling methods are partly design-based constrains the spatial resolution at which animal density can be estimated using these methods. Estimates are usually obtained at survey stratum level. For an endangered species such as the blue whale, it is desirable to estimate density and abundance at a finer spatial scale than stratum. Temporal variation in the spatial structure is also important. We formulate the process generating distance sampling data as a thinned spatial point process and propose model-based inference using a spatial log-Gaussian Cox process. The method adopts a flexible stochastic partial differential equation (SPDE) approach to model spatial structure in density that is not accounted for by explanatory variables, and integrated nested Laplace approximation (INLA) for Bayesian inference. It allows simultaneous fitting of detection and density models and permits prediction of density at an arbitrarily fine scale. We estimate blue whale density in the Eastern Tropical Pacific Ocean from thirteen shipboard surveys conducted over 22 years. We find that higher blue whale density is associated with colder sea surface temperatures in space, and although there is some positive association between density and mean annual temperature, our estimates are consistent with no trend in density across years. Our analysis also indicates that there is substantial spatially structured variation in density that is not explained by available covariates.

  12. Giant congenital cellular blue nevus of the scalp: neonatal presentation and approach

    Directory of Open Access Journals (Sweden)

    Debyser M

    2011-12-01

    Full Text Available Martine Debyser1, Sofie De Schepper2, James D'haese1, Veerle De Ketelaere3, Luc Cornette11Neonatal Intensive Care Unit AZ St Jan Bruges-Ostend AV, Bruges, Belgium; 2Department of Dermatology, Ghent University Hospital, Ghent, Belgium; 3Department of Paediatrics, St Rembert Hospital, Torhout, BelgiumAbstract: The authors report the case of a massive vaginal bleeding during labor and delivery, resulting in the birth of a newborn infant in hypovolemic shock. The origin of the bleeding was a giant congenital cellular blue nevus (CBN of the scalp. The report illustrates the crucial role of immediate and aggressive volume resuscitation, suturing of the skin dehiscence, and firm external compression. This therapy was combined with whole-body hypothermia. The neurological outcome of the patient was normal. A shiny blue mass on the scalp should alert neonatologists to the possibility of a blue nevus of the scalp, rather than a simple scalp hematoma. Final diagnosis is made by biopsy and histologic examination. Early surgical intervention is necessary to prevent malignant degeneration and metastasis. A multidisciplinary approach involving a pediatrician/neonatologist, dermatologist, and surgeon is thus needed for diagnosis, treatment, and long-term follow-up.Keywords: neonate, cellular blue nevus, giant blue nevus, giant congenital blue nevus, hemorrhagic shock, whole-body hypothermia

  13. ProFile Vortex and Vortex Blue Nickel-Titanium Rotary Instruments after Clinical Use.

    Science.gov (United States)

    Shen, Ya; Zhou, Huimin; Coil, Jeffrey M; Aljazaeri, Bassim; Buttar, Rene; Wang, Zhejun; Zheng, Yu-feng; Haapasalo, Markus

    2015-06-01

    The aim of this study was to analyze the incidence and mode of ProFile Vortex and Vortex Blue instrument defects after clinical use in a graduate endodontic program and to examine the impact of clinical use on the instruments' metallurgical properties. A total of 330 ProFile Vortex and 1136 Vortex Blue instruments from the graduate program were collected after each had been used in 3 teeth. The incidence and type of instrument defects were analyzed. The lateral surfaces and fracture surfaces of the fractured files were examined by using scanning electron microscopy. Unused and used instruments were examined by full and partial differential scanning calorimetry. No fractures were observed in the 330 ProFile Vortex instruments, whereas 20 (6.1%) revealed bent or blunt defects. Only 2 of the 1136 Vortex Blue files fractured during clinical use. The cause of fracture was shear stress. The fractures occurred at the tip end of the spirals. Only 1.8% (21 of 1136) of the Vortex Blue files had blunt tips. Austenite-finish temperatures were very similar for unused and used ProFile Vortex files and were all greater than 50°C. The austenite-finish temperatures of used and unused Vortex Blue files (38.5°C) were lower than those in ProFile Vortex instruments (P Vortex Blue files had an obvious 2-stage transformation, martensite-to-R phase and R-to-austenite phase. The trends of differential scanning calorimetry plots of unused Vortex Blue instruments and clinically used instruments were very similar. The risk of ProFile Vortex and Vortex Blue instrument fracture is very low when instruments are discarded after clinical use in the graduate endodontic program. The Vortex Blue files have metallurgical behavior different from ProFile Vortex instruments. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  14. ''Blue clearing'' on Mars in connection with dust clouds in August and September 1971

    International Nuclear Information System (INIS)

    Prokof'eva, V.V.; Chuprakova, T.A.; Dzyamko, S.S.; Bryzgalova, T.V.

    1975-01-01

    Photometric processing of Mars TV pictures obtained in ultraviolet, blue, green and red spectrum regions reveals the connection of the ''blue clearing'' effect with the appearance of dust clouds above the light regions of the planet. The obtained data confirm the hypothesis about the dust nature of blue clearings: the illusion of blue clearings is produced as a result of increasing brightness of thse Mars light regions, when dust clouds apr above them

  15. Hazard Prevention Regarding Occupational Accidents Involving Blue-Collar Foreign Workers: A Perspective of Taiwanese Manpower Agencies.

    Science.gov (United States)

    Chang, Huan-Cheng; Wang, Mei-Chin; Liao, Hung-Chang; Cheng, Shu-Fang; Wang, Ya-Huei

    2016-07-13

    Since 1989, blue-collar foreign workers have been permitted to work in Taiwanese industries. Most blue-collar foreign workers apply for jobs in Taiwan through blue-collar foreign workers' agencies. Because blue-collar foreign workers are not familiar with the language and culture in Taiwan, in occupational accident education and hazard prevention, the agencies play an important role in the coordination and translation between employees and blue-collar foreign workers. The purpose of this study is to establish the agencies' role in the occupational accidents education and hazard prevention for blue-collar foreign workers in Taiwan. This study uses a qualitative method-grounded theory-to collect, code, and analyze the data in order to understand the agencies' role in occupational accident education and hazard prevention for blue-collar foreign workers in Taiwan. The results show that the duty of agencies in occupational accident education and hazard prevention includes selecting appropriate blue-collar foreign workers, communicating between employees and blue-collar foreign workers, collecting occupational safety and health information, assisting in the training of occupational safety and health, and helping blue-collar foreign workers adapt to their lives in Taiwan. Finally, this study suggests seven important points and discusses the implementation process necessary to improve governmental policies. The government and employees should pay attention to the education/training of occupational safety and health for blue-collar foreign workers to eliminate unsafe behavior in order to protect the lives of blue-collar foreign workers.

  16. Hazard Prevention Regarding Occupational Accidents Involving Blue-Collar Foreign Workers: A Perspective of Taiwanese Manpower Agencies

    Directory of Open Access Journals (Sweden)

    Huan-Cheng Chang

    2016-07-01

    Full Text Available Since 1989, blue-collar foreign workers have been permitted to work in Taiwanese industries. Most blue-collar foreign workers apply for jobs in Taiwan through blue-collar foreign workers’ agencies. Because blue-collar foreign workers are not familiar with the language and culture in Taiwan, in occupational accident education and hazard prevention, the agencies play an important role in the coordination and translation between employees and blue-collar foreign workers. The purpose of this study is to establish the agencies’ role in the occupational accidents education and hazard prevention for blue-collar foreign workers in Taiwan. This study uses a qualitative method—grounded theory—to collect, code, and analyze the data in order to understand the agencies’ role in occupational accident education and hazard prevention for blue-collar foreign workers in Taiwan. The results show that the duty of agencies in occupational accident education and hazard prevention includes selecting appropriate blue-collar foreign workers, communicating between employees and blue-collar foreign workers, collecting occupational safety and health information, assisting in the training of occupational safety and health, and helping blue-collar foreign workers adapt to their lives in Taiwan. Finally, this study suggests seven important points and discusses the implementation process necessary to improve governmental policies. The government and employees should pay attention to the education/training of occupational safety and health for blue-collar foreign workers to eliminate unsafe behavior in order to protect the lives of blue-collar foreign workers.

  17. Blue Oak Canopy Effect on Seasonal Forage Production and Quality

    Science.gov (United States)

    William E. Frost; Neil K. McDougald; Montague W. Demment

    1991-01-01

    Forage production and forage quality were measured seasonally beneath the canopy of blue oak (Quercus douglasii) and in open grassland at the San Joaquin Experimental Range. At the March and peak standing crop sampling dates forage production was significantly greater (p=.05) beneath blue oak compared to open grassland. At most sampling dates, the...

  18. Anti-cytomegalovirus activity of the anthraquinone atanyl blue PRL.

    Science.gov (United States)

    Alam, Zohaib; Al-Mahdi, Zainab; Zhu, Yali; McKee, Zachary; Parris, Deborah S; Parikh, Hardik I; Kellogg, Glen E; Kuchta, Alison; McVoy, Michael A

    2015-02-01

    Human cytomegalovirus (CMV) causes significant disease in immunocompromised patients and serious birth defects if acquired in utero. Available CMV antivirals target the viral DNA polymerase, have significant toxicities, and suffer from resistance. New drugs targeting different pathways would be beneficial. The anthraquinone emodin is proposed to inhibit herpes simplex virus by blocking the viral nuclease. Emodin and related anthraquinones are also reported to inhibit CMV. In the present study, emodin reduced CMV infectious yield with an EC50 of 4.9μM but was cytotoxic at concentrations only twofold higher. Related anthraquinones acid blue 40 and alizarin violet R inhibited CMV at only high concentrations (238-265μM) that were also cytotoxic. However, atanyl blue PRL inhibited infectious yield of CMV with an EC50 of 6.3μM, significantly below its 50% cytotoxic concentration of 216μM. Atanyl blue PRL reduced CMV infectivity and inhibited spread. When added up to 1h after infection, it dramatically reduced CMV immediate early protein expression and blocked viral DNA synthesis. However, it had no antiviral activity when added 24h after infection. Interestingly, atanyl blue PRL inhibited nuclease activities of purified CMV UL98 protein with IC50 of 4.5 and 9.3μM. These results indicate that atanyl blue PRL targets very early post-entry events in CMV replication and suggest it may act through inhibition of UL98, making it a novel CMV inhibitor. This compound may provide valuable insights into molecular events that occur at the earliest times post-infection and serve as a lead structure for antiviral development. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Blue Light Emitting Polyphenylene Dendrimers with Bipolar Charge Transport Moieties

    Directory of Open Access Journals (Sweden)

    Guang Zhang

    2016-10-01

    Full Text Available Two light-emitting polyphenylene dendrimers with both hole and electron transporting moieties were synthesized and characterized. Both molecules exhibited pure blue emission solely from the pyrene core and efficient surface-to-core energy transfers when characterized in a nonpolar environment. In particular, the carbazole- and oxadiazole-functionalized dendrimer (D1 manifested a pure blue emission from the pyrene core without showing intramolecular charge transfer (ICT in environments with increasing polarity. On the other hand, the triphenylamine- and oxadiazole-functionalized one (D2 displayed notable ICT with dual emission from both the core and an ICT state in highly polar solvents. D1, in a three-layer organic light emitting diode (OLED by solution processing gave a pure blue emission with Commission Internationale de l’Éclairage 1931 CIE xy = (0.16, 0.12, a peak current efficiency of 0.21 cd/A and a peak luminance of 2700 cd/m2. This represents the first reported pure blue dendrimer emitter with bipolar charge transport and surface-to-core energy transfer in OLEDs.

  20. Blue Light Emitting Polyphenylene Dendrimers with Bipolar Charge Transport Moieties.

    Science.gov (United States)

    Zhang, Guang; Auer-Berger, Manuel; Gehrig, Dominik W; Blom, Paul W M; Baumgarten, Martin; Schollmeyer, Dieter; List-Kratochvil, E J W; Müllen, Klaus

    2016-10-20

    Two light-emitting polyphenylene dendrimers with both hole and electron transporting moieties were synthesized and characterized. Both molecules exhibited pure blue emission solely from the pyrene core and efficient surface-to-core energy transfers when characterized in a nonpolar environment. In particular, the carbazole- and oxadiazole-functionalized dendrimer ( D1 ) manifested a pure blue emission from the pyrene core without showing intramolecular charge transfer (ICT) in environments with increasing polarity. On the other hand, the triphenylamine- and oxadiazole-functionalized one ( D2 ) displayed notable ICT with dual emission from both the core and an ICT state in highly polar solvents. D1 , in a three-layer organic light emitting diode (OLED) by solution processing gave a pure blue emission with Commission Internationale de l'Éclairage 1931 CIE xy = (0.16, 0.12), a peak current efficiency of 0.21 cd/A and a peak luminance of 2700 cd/m². This represents the first reported pure blue dendrimer emitter with bipolar charge transport and surface-to-core energy transfer in OLEDs.

  1. Blue light irradiation-induced oxidative stress in vivo via ROS generation in rat gingival tissue.

    Science.gov (United States)

    Yoshida, Ayaka; Shiotsu-Ogura, Yukako; Wada-Takahashi, Satoko; Takahashi, Shun-suke; Toyama, Toshizo; Yoshino, Fumihiko

    2015-10-01

    It has been reported that oxidative stress with reactive oxygen species (ROS) generation is induced by blue light irradiation to a living body. Only limited research has been reported in dental field on the dangers of blue light, mostly focusing on cytotoxicity associated with heat injury of dental pulp. We thus performed an in vivo study on oral tissue exposed to blue light. ROS generated upon blue light irradiation of flavin adenine dinucleotide were measured by electron spin resonance spectroscopy. After blue light irradiation, the palatal gingiva of Wistar rats were isolated. Collected samples were subjected to biochemical analysis of lipid peroxidation and glutathione. Singlet oxygen was generated by blue light irradiation, but was significantly quenched in an N-acetyl-L-cysteine (NAC) concentration-dependent manner. Blue light significantly accelerated oxidative stress and increased the oxidized glutathione levels in gingival tissue. These effects were also inhibited by NAC pre-administration. The results suggest that blue light irradiation at clinical levels of tooth bleaching treatment may enhance lipid peroxidation by the induction of oxidative stress and the consumption of a significant amount of intracellular glutathione. In addition, NAC might be an effective supplement for the protection of oral tissues against blue light irradiation-induced oxidative damage. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. A New Kind of Blue Hybrid Electroluminescent Device.

    Science.gov (United States)

    Wang, Junling; Li, Zhuan; Liu, Chunmei

    2016-04-01

    Bright blue Electroluminescence come from a ITO/BBOT doped silica (6 x 10(-3) M) made by a sol-gel method/Al driven by AC with 500 Hz at different voltages and Gaussian analysis under 55 V showed that blue emission coincidenced with typical triple emission from BBOT. This kind of device take advantage of organics (BBOT) and inorganics (silica). Electroluminescence from a single-layered sandwiched device consisting of blue fluorescent dye 2,5-bis (5-tert-butyl-2-benzoxazolyl) thiophene (BBOT) doped silica made by sol-gel method was investigated. A number of concentrations of hybrid devices were prepared and the maxium concentration was 6 x 10(-3) M. Blue electroluminescent (EL) always occurred above a threshold field 8.57 x 10(5) V/cm (30 V) at alternating voltage at 500 HZ. The luminance of the devices increased with the concentration of doped BBOT, but electroluminescence characteristics were different from a single molecule's photoluminescence properties of triple peaks. When analyzing in detail direct-current electroluminescence devices of pure BBOT, a single peak centered at 2.82 eV appeared with the driven voltage increase, which is similar to the hybrid devices. Comparing Gaussian decomposition date between two kinds of devices, the triple peak characteristic of BBOT was consistent. It is inferred that BBOT contributed EL of the hybrid devices mainly and silica may account for a very small part. Meanwhile the thermal stability of matrix silica was measured by Thermal Gravity-Mass Spectroscopy (TG-MS). There is 12 percent weight loss from room temperature to 1000 °C and silica has about 95% transmittance. So the matric silica played an important role in thermal stability and optical stability for BBOT. In addition, this kind of blue electroluminescence device can take advantages of organic materials BBOT and inorganic materials silica. This is a promising way to enrich EL devices, especially enriching inorganic EL color at a low cost.

  3. Manufacturing Gender Inequality in the New Economy: High School Training for Work in Blue-Collar Communities.

    Science.gov (United States)

    Sutton, April; Bosky, Amanda; Muller, Chandra

    2016-08-01

    Tensions between the demands of the knowledge-based economy and remaining, blue-collar jobs underlie renewed debates about whether schools should emphasize career and technical training or college-preparatory curricula. We add a gendered lens to this issue, given the male-dominated nature of blue-collar jobs and women's greater returns to college. Using the ELS:2002, this study exploits spatial variation in school curricula and jobs to investigate local dynamics that shape gender stratification. Results suggest a link between high school training and jobs in blue-collar communities that structures patterns of gender inequality into early adulthood. Although high school training in blue-collar communities reduced both men's and women's odds of four-year college enrollment, it had gender-divergent labor market consequences. Men in blue-collar communities took more blue-collar courses, had higher rates of blue-collar employment, and earned similar wages relative to otherwise comparable men from non-blue-collar communities. Women were less likely to work and to be employed in professional occupations, and they suffered severe wage penalties relative to their male peers and women from non-blue-collar communities. These relationships were due partly to high schools in blue-collar communities offering more blue-collar and fewer advanced college-preparatory courses. This curricular tradeoff may benefit men, but it appears to disadvantage women.

  4. Experimental determination of deflagration velocity and blue cone height for natural gases from Guajira and Cusiana

    International Nuclear Information System (INIS)

    Fernandez Martinez, Alejandro; Piza Molina, Carlos Andres; Vanegas Jaramillo, Gilmar Adoni

    2001-01-01

    In this project the conical flame method was implemented to measure deflagration rate and a direct photography method to measure the height of blue cone for to natural gases with Guajira and Cusiana composition. Besides of these the existent relation between both variables was determined. The information obtained in this work is fundamental, as long as it provides an experimental method that applied to real conditions, allows the characterization of the natural gases of Guajira and Cusiana, witch will be of utility to define criterions of de sing and interchange ability in the commercial and industrial combustion systems

  5. High-level methodology for carrying out combined red and blue teams

    CSIR Research Space (South Africa)

    Veerasamy, N

    2009-12-01

    Full Text Available This paper proposes a combined Red and Blue Team Methodology to guide the process of carrying out such security auditing and penetration testing tasks. Red and Blue Teams consist of various security auditing and penetration testing tasks which serve...

  6. Effects of fire and browsing on regeneration of blue oak

    Science.gov (United States)

    James W. Bartolome; Mitchel P. McClaran; Barbara H. Allen-Diaz; Jim Dunne; Lawrence D. Ford; Richard B. Standiford; Neil K. McDougald; Larry C. Forero

    2002-01-01

    Blue oaks (Quercus douglasii) are not regenerating well over much of California. The roles of fire and browsing in regeneration are probably significant, but poorly understood. We burned two foothill blue oak woodland sites which contained significant numbers of small trees between 40 and 70 cm tall, then compared height growth over 14 years among 48...

  7. Low luminance/eyes closed and monochromatic stimulations reduce variability of flash visual evoked potential latency

    Directory of Open Access Journals (Sweden)

    Senthil Kumar Subramanian

    2013-01-01

    Full Text Available Context: Visual evoked potentials are useful in investigating the physiology and pathophysiology of the human visual system. Flash visual evoked potential (FVEP, though technically easier, has less clinical utility because it shows great variations in both latency and amplitude for normal subjects. Aim: To study the effect of eye closure, low luminance, and monochromatic stimulation on the variability of FVEPs. Subjects and Methods: Subjects in self-reported good health in the age group of 18-30 years were divided into three groups. All participants underwent FVEP recording with eyes open and with white light at 0.6 J luminance (standard technique. Next recording was done in group 1 with closed eyes, group 2 with 1.2 and 20 J luminance, and group 3 with red and blue lights, while keeping all the other parameters constant. Two trials were given for each eye, for each technique. The same procedure was repeated at the same clock time on the following day. Statistical Analysis: Variation in FVEP latencies between the individuals (interindividual variability and the variations within the same individual for four trials (intraindividual variability were assessed using coefficient of variance (COV. The technique with lower COV was considered the better method. Results: Recording done with closed eyes, 0.6 J luminance, and monochromatic light (blue > red showed lower interindividual and intraindividual variability in P2 and N2 as compared to standard techniques. Conclusions: Low luminance flash stimulations and monochromatic light will reduce FVEP latency variability and may be clinically useful modifications of FVEP recording technique.

  8. Blue and near ultraviolet reversible photoreaction in the induction of fungal conidiation

    International Nuclear Information System (INIS)

    Kumagai, T.

    1982-01-01

    The effects of blue light and near UV light on the induction of conidiation in the fungus, Alternaria tomato, were investigated. Induction of conidiation was repeatedly controlled by alternating doses of near UV light and blue light. When the final light was near UV, conidiation was induced and conidia developed in the following darkness; when it was blue, the induction of conidiation was suppressed. When conidiation was induced by irradiation with a light mixed with near UV and blue, not only the time lag for inducing conidiation but also the amount of conidia formed were regulated by the fluence rates of both those lights. Thus, 'mycochrome' is considered to function as a photoreceptor system in the induction of conidiation of this fungus. (author)

  9. Evaluation of blue light exposure to beta brainwaves on simulated night driving

    Science.gov (United States)

    Purawijaya, Dandri Aly; Fitri, Lulu Lusianti; Suprijanto

    2015-09-01

    Numbers of night driving accident in Indonesia since 2010 are exponentially rising each year with total of loss more than 50 billion rupiah. One of the causes that contribute to night driving accident is drowsiness. Drowsiness is affected by circadian rhythm resulted from the difference of blue light quality and quantity between night and day. Blue light may effect on human physiology through non-visual pathway by suppressing melatonin hormone suppression that influence drowsiness. Meanwhile, the production of hormones and other activities in brain generate bioelectrical activity such as brainwaves and can be recorded using Electroencephalograph (EEG). Therefore, this research objective is to evaluate the effect of blue light exposure to beta brainwave emergence during night driving simulation to a driver. This research was conducted to 4 male subjects who are able to drive and have a legitimate car driving license. The driving simulator was done using SCANIA Truck Driving Simulator on freeform driving mode in dark environment. Subjects drove for total 32 minutes. The data collections were taken in 2 days with 16 minutes for each day. The 16 minutes were divided again into 8 minutes adaptation in dark and 8 minutes for driving either in blue light exposure or in total darkness. While driving the simulation, subjects' brainwaves were recorded using EEG EMOTIV 14 Channels, exposed by LED monochromatic blue light with 160 Lux from source and angle 45o and sat 1 m in front of the screen. Channels used on this research were for visual (O1; O2), cognition (F3; F4; P7; P8), and motor (FC5; FC6). EEG brainwave result was filtered with EEGLab to obtain beta waves at 13 - 30 Hz frequencies. Results showed that beta waves response to blue light varied for each subject. Blue light exposure either increased or decreased beta waves in 2 minutes pattern and maintaining beta waves on cognition and motor area in 3 out of 4 subjects. Meanwhile, blue light exposure did not maintain

  10. Capacity constrained blue-noise sampling on surfaces

    KAUST Repository

    Zhang, Sen

    2015-11-27

    We present a novel method for high-quality blue-noise sampling on mesh surfaces with prescribed cell-sizes for the underlying tessellation (capacity constraint). Unlike the previous surface sampling approach that only uses capacity constraints as a regularizer of the Centroidal Voronoi Tessellation (CVT) energy, our approach enforces an exact capacity constraint using the restricted power tessellation on surfaces. Our approach is a generalization of the previous 2D blue noise sampling technique using an interleaving optimization framework. We further extend this framework to handle multi-capacity constraints. We compare our approach with several state-of-the-art methods and demonstrate that our results are superior to previous work in terms of preserving the capacity constraints.

  11. Prussian Blue Analogues of Reduced Dimensionality

    NARCIS (Netherlands)

    Gengler, Regis Y. N.; Toma, Luminita M.; Pardo, Emilio; Lloret, Francesc; Ke, Xiaoxing; Van Tendeloo, Gustaaf; Gournis, Dimitrios; Rudolf, Petra

    2012-01-01

    Mixed-valence polycyanides (Prussian Blue analogues) possess a rich palette of properties spanning from room-temperature ferromagnetism to zero thermal expansion, which can be tuned by chemical modifications or the application of external stimuli (temperature, pressure, light irradiation). While

  12. Staring at the cold sun: blue light regulation is distributed within the genus Acinetobacter.

    Directory of Open Access Journals (Sweden)

    Adrián Golic

    Full Text Available We previously showed that the opportunistic nosocomial pathogen Acinetobacter baumannii is able to sense and respond to light via BlsA, a BLUF (Blue-Light-sensing Using FAD-domain photoreceptor protein. Here, we extend our previous studies showing that light regulation is not restricted to A. baumannii, but rather widespread within the genus Acinetobacter. First, we found that blue light modulates motility and biofilm formation in many species of the genus, including members of the Acinetobacter calcoaceticus-A. baumannii complex. In many of these species blue light acts as a key factor guiding the decision between motility or sessility at 24°C, whereas in A. baumannii, light inhibits both motility and biofilm formation. We also show that light regulation of motility occurred not only at 24°C but also at 37°C in non-A. baumannii species, contrasting the situation of A. baumannii which only shows photoregulation at 24°C. Second, we show that Acinetobacter baylyi (strain ADP1 BLUF-photoreceptors can functionally replace in vivo the A. baumannii 17978 BlsA protein and that the pathways leading to biofilm formation are inversely regulated at 24°C between these two microorganisms. Finally, we found the presence of predicted genes coding BLUF-containing proteins in all Acinetobacter sequenced genomes, even though the copy number is variable among them. Phylogenetic analysis suggests a common origin for all BLUF domains present in members of this genus, and could distinguish well-differentiated clusters that group together BLUF homologs from different species, a situation particularly clear for members of the ACB complex. Despite a role played by these BLUF domain-containing proteins in the photoregulation observed in the members of the genus Acinetobacter is a likely scenario given our findings in A. baumannii and A. baylyi, further research will contribute to confirm this possibility.

  13. Staring at the Cold Sun: Blue Light Regulation Is Distributed within the Genus Acinetobacter

    Science.gov (United States)

    Golic, Adrián; Vaneechoutte, Mario; Nemec, Alexandr; Viale, Alejandro M.; Actis, Luis A.; Mussi, María Alejandra

    2013-01-01

    We previously showed that the opportunistic nosocomial pathogen Acinetobacter baumannii is able to sense and respond to light via BlsA, a BLUF (Blue-Light-sensing Using FAD)-domain photoreceptor protein. Here, we extend our previous studies showing that light regulation is not restricted to A. baumannii, but rather widespread within the genus Acinetobacter. First, we found that blue light modulates motility and biofilm formation in many species of the genus, including members of the Acinetobacter calcoaceticus-A. baumannii complex. In many of these species blue light acts as a key factor guiding the decision between motility or sessility at 24°C, whereas in A. baumannii, light inhibits both motility and biofilm formation. We also show that light regulation of motility occurred not only at 24°C but also at 37°C in non-A. baumannii species, contrasting the situation of A. baumannii which only shows photoregulation at 24°C. Second, we show that Acinetobacter baylyi (strain ADP1) BLUF-photoreceptors can functionally replace in vivo the A. baumannii 17978 BlsA protein and that the pathways leading to biofilm formation are inversely regulated at 24°C between these two microorganisms. Finally, we found the presence of predicted genes coding BLUF-containing proteins in all Acinetobacter sequenced genomes, even though the copy number is variable among them. Phylogenetic analysis suggests a common origin for all BLUF domains present in members of this genus, and could distinguish well-differentiated clusters that group together BLUF homologs from different species, a situation particularly clear for members of the ACB complex. Despite a role played by these BLUF domain-containing proteins in the photoregulation observed in the members of the genus Acinetobacter is a likely scenario given our findings in A. baumannii and A. baylyi, further research will contribute to confirm this possibility. PMID:23358859

  14. Preoperative Localization of Mediastinal Parathyroid Adenoma with Intra-arterial Methylene Blue

    Energy Technology Data Exchange (ETDEWEB)

    Salman, Rida; Sebaaly, Mikhael G. [American University of Beirut Medical Center, Department of Diagnostic Radiology (Lebanon); Wehbe, Mohammad Rachad; Sfeir, Pierre; Khalife, Mohamad [American University of Beirut Medical Center, Department of General Surgery (Lebanon); Al-Kutoubi, Aghiad, E-mail: mk00@aub.edu.lb [American University of Beirut Medical Center, Department of Diagnostic Radiology (Lebanon)

    2017-06-15

    Ectopic parathyroid is found in 16% of patients with hyperparathyroidism. 2% of ectopic parathyroid adenomas are not accessible to standard cervical excision. In such cases, video-assisted thoracoscopic resection is the recommended definitive treatment. We present a case of mediastinal parathyroid adenoma localized preoperatively by injecting methylene blue within a branch of the internal mammary artery that is supplying the adenoma. Intra-arterial methylene blue injection facilitated visualization and resection of the adenoma. The preoperative intra-arterial infusion of methylene blue appears to be an effective and safe method for localization of ectopic mediastinal parathyroid adenomas and allows rapid identification during thoracoscopic resection.

  15. Enhancement of autonomic and psychomotor arousal by exposures to blue wavelength light: importance of both absolute and relative contents of melanopic component.

    Science.gov (United States)

    Yuda, Emi; Ogasawara, Hiroki; Yoshida, Yutaka; Hayano, Junichiro

    2017-01-31

    Blue light containing rich melanopsin-stimulating (melanopic) component has been reported to enhance arousal level, but it is unclear whether the determinant of the effects is the absolute or relative content of melanopic component. We compared the autonomic and psychomotor arousal effects of melanopic-enriched blue light of organic light-emitting diode (OLED) with those of OLED lights with lesser absolute amount of melanopic component (green light) and with greater absolute but lesser relative content (white light). Using a ceiling light consisting of 120 panels (55 × 55 mm square) of OLED modules with adjustable color and brightness, we examined the effects of blue, green, and white lights (melanopic photon flux densities, 0.23, 0.14, and 0.38 μmol/m 2 /s and its relative content ratios, 72, 17, and 14%, respectively) on heart rate variability (HRV) during exposures and on the performance of psychomotor vigilance test (PVT) after exposures in ten healthy subjects with normal color vision. For each of the three colors, five consecutive 10-min sessions of light exposures were performed in the supine position, interleaved by four 10-min intervals during which 5-min PVT was performed under usual fluorescent light in sitting position. Low-frequency (LF, 0.04-0.15 Hz) and high-frequency (HF, 0.15-0.40 Hz) power and LF-to-HF ratio (LF/HF) of HRV during light exposures and reaction time (RT) and minor lapse (RT >500 ms) of PVT were analyzed. Heart rate was higher and the HF power reflecting autonomic resting was lower during exposures to the blue light than the green and white lights, while LF/HF did not differ significantly. Also, the number of minor lapse and the variation of reaction time reflecting decreased vigilance were lower after exposures to the blue light than the green light. The effects of blue OLED light for maintaining autonomic and psychomotor arousal levels depend on both absolute and relative contents of melanopic component in the light.

  16. Improper, Blue-Shifting Hydrogen Bond

    Czech Academy of Sciences Publication Activity Database

    Hobza, Pavel; Havlas, Zdeněk

    2002-01-01

    Roč. 108, - (2002), s. 325-334 ISSN 1432-881X R&D Projects: GA MŠk LN00A032 Institutional research plan: CEZ:AV0Z4055905; CEZ:AV0Z4040901 Keywords : improper, blue-shifting hydrogen bond * properties * nature Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.421, year: 2002

  17. Generation of blue chrysanthemums by anthocyanin B-ring hydroxylation and glucosylation and its coloration mechanism.

    Science.gov (United States)

    Noda, Naonobu; Yoshioka, Satoshi; Kishimoto, Sanae; Nakayama, Masayoshi; Douzono, Mitsuru; Tanaka, Yoshikazu; Aida, Ryutaro

    2017-07-01

    Various colored cultivars of ornamental flowers have been bred by hybridization and mutation breeding; however, the generation of blue flowers for major cut flower plants, such as roses, chrysanthemums, and carnations, has not been achieved by conventional breeding or genetic engineering. Most blue-hued flowers contain delphinidin-based anthocyanins; therefore, delphinidin-producing carnation, rose, and chrysanthemum flowers have been generated by overexpression of the gene encoding flavonoid 3',5'-hydroxylase (F3'5'H), the key enzyme for delphinidin biosynthesis. Even so, the flowers are purple/violet rather than blue. To generate true blue flowers, blue pigments, such as polyacylated anthocyanins and metal complexes, must be introduced by metabolic engineering; however, introducing and controlling multiple transgenes in plants are complicated processes. We succeeded in generating blue chrysanthemum flowers by introduction of butterfly pea UDP (uridine diphosphate)-glucose:anthocyanin 3',5'- O -glucosyltransferase gene, in addition to the expression of the Canterbury bells F3'5'H . Newly synthesized 3',5'-diglucosylated delphinidin-based anthocyanins exhibited a violet color under the weakly acidic pH conditions of flower petal juice and showed a blue color only through intermolecular association, termed "copigmentation," with flavone glucosides in planta. Thus, we achieved the development of blue color by a two-step modification of the anthocyanin structure. This simple method is a promising approach to generate blue flowers in various ornamental plants by metabolic engineering.

  18. [The role of some psychological, psychosocial and obstetrical factors in the intensity of postpartum blues].

    Science.gov (United States)

    Séjourné, N; Denis, A; Theux, G; Chabrol, H

    2008-04-01

    Within days following birth, most women show signs of mood changes, commonly named baby blues. Baby blues can result in postpartum depression. Hence it appears important to explore in more details the clinical background related to the intensity of postpartum blues. The aim of this study is to investigate the contribution of psychological, psychosocial and obstetrical factors to the intensity of postpartum blues. One hundred and forty-eight women participated in the study and completed questionnaires three days after delivery. A questionnaire was built to collect information on psychosocial and obstetrical factors. The Maternity Blues (Kennerley and Gath, 1989) was used to assess postpartum blues. Psychological factors were measured with the Maternal Self-Report Inventory (Shea et Tronick, 1988), the Perceived Stress Scale (Cohen, Kamarch et Mermelstein, 1983) and the Sarason's Social Support Questionnaire (1983). Four multiple regression analyses were conducted to predict the intensity of postpartum blues by entering psychosocial factors, history of depression, obstetrical factors and psychological and relational factors. Significant predictors (maternal self-esteem, marital status, previous psychotherapeutic treatment, previous antidepressant treatment) were entered in a multiple regression analysis predicting the intensity of postpartum blues. This model accounted for 31% of the variance in the intensity of postpartum blues (F(4, 143)=17.9; Pself-esteem (beta=-0.37; Porder to detect women who exhibit risk factors.

  19. Observations of Blue Discharges Associated With Negative Narrow Bipolar Events in Active Deep Convection

    Science.gov (United States)

    Liu, Feifan; Zhu, Baoyou; Lu, Gaopeng; Qin, Zilong; Lei, Jiuhou; Peng, Kang-Ming; Chen, Alfred B.; Huang, Anjing; Cummer, Steven A.; Chen, Mingli; Ma, Ming; Lyu, Fanchao; Zhou, Helin

    2018-03-01

    On 19 August 2012, the Imager of Sprites and Upper Atmospheric Lightning on board the FORMOSAT-2 satellite captured a sequence of seven blue discharges within 1 min that emanated from a parent thunderstorm over Lake Taihu in East China. The analysis of lightning activity produced in the thunderstorm indicates that at least six of these events occurred in association with negative narrow bipolar events (NBEs) that were concurrent with the blue discharge by less than 1 ms, and negative cloud-to-ground occurred within 6 s before each blue discharge, which is in agreement with the modeling presented by Krehbiel et al. (2008). Therefore, the frequent occurrence of negative cloud-to-ground could provide the favorable condition for the production of blue discharges, and negative NBEs are probably the initial event of blue discharges. The detection of negative NBEs might provide a convenient approach to detect the occurrence of blue discharges as lightning bolt shooting upward from the top of energetic thunderstorms.

  20. The Cluster AgeS Experiment (CASE). Variable Stars in the Field of the Globular Cluster M22

    Science.gov (United States)

    Rozyczka, M.; Thompson, I. B.; Pych, W.; Narloch, W.; Poleski, R.; Schwarzenberg-Czerny, A.

    2017-09-01

    The field of the globular cluster M22 (NGC 6656) was monitored between 2000 and 2008 in a search for variable stars. BV light curves were obtained for 359 periodic, likely periodic, and long-term variables, 238 of which are new detections. 39 newly detected variables, and 63 previously known ones are members or likely members of the cluster, including 20 SX Phe, 10 RRab and 16 RRc type pulsators, one BL Her type pulsator, 21 contact binaries, and 9 detached or semi-detached eclipsing binaries. The most interesting among the identified objects are V112 - a bright multimode SX Phe pulsator, V125 - a β Lyr type binary on the blue horizontal branch, V129 - a blue/yellow straggler with a W UMa-like light curve, located halfway between the extreme horizontal branch and red giant branch, and V134 - an extreme horizontal branch object with P=2.33 d and a nearly sinusoidal light curve. All four of them are proper motion members of the cluster. Among nonmembers, a P=2.83 d detached eclipsing binary hosting a δ Sct type pulsator was found, and a peculiar P=0.93 d binary with ellipsoidal modulation and narrow minimum in the middle of one of the descending shoulders of the sinusoid. We also collected substantial new data for previously known variables. In particular we revise the statistics of the occurrence of the Blazhko effect in RR Lyr type variables of M22.

  1. A comparison of blue light and caffeine effects on cognitive function and alertness in humans.

    Science.gov (United States)

    Beaven, C Martyn; Ekström, Johan

    2013-01-01

    The alerting effects of both caffeine and short wavelength (blue) light have been consistently reported. The ability of blue light to enhance alertness and cognitive function via non-image forming neuropathways have been suggested as a non-pharmacological countermeasure for drowsiness across a range of occupational settings. Here we compare and contrast the alerting and psychomotor effects of 240 mg of caffeine and a 1-h dose of ~40 lx blue light in a non-athletic population. Twenty-one healthy subjects performed a computer-based psychomotor vigilance test before and after each of four randomly assigned trial conditions performed on different days: white light/placebo; white light/240 mg caffeine; blue light/placebo; blue light/240 mg caffeine. The Karolinska Sleepiness Scale was used to assess subjective measures of alertness. Both the caffeine only and blue light only conditions enhanced accuracy in a visual reaction test requiring a decision and an additive effect was observed with respect to the fastest reaction times. However, in a test of executive function, where a distraction was included, caffeine exerted a negative effect on accuracy. Furthermore, the blue light only condition consistently outperformed caffeine when both congruent and incongruent distractions were presented. The visual reactions in the absence of a decision or distraction were also enhanced in the blue light only condition and this effect was most prominent in the blue-eyed participants. Overall, blue light and caffeine demonstrated distinct effects on aspects of psychomotor function and have the potential to positively influence a range of settings where cognitive function and alertness are important. Specifically, despite the widespread use of caffeine in competitive sporting environments, the possible impact of blue light has received no research attention.

  2. A comparison of blue light and caffeine effects on cognitive function and alertness in humans.

    Directory of Open Access Journals (Sweden)

    C Martyn Beaven

    Full Text Available The alerting effects of both caffeine and short wavelength (blue light have been consistently reported. The ability of blue light to enhance alertness and cognitive function via non-image forming neuropathways have been suggested as a non-pharmacological countermeasure for drowsiness across a range of occupational settings. Here we compare and contrast the alerting and psychomotor effects of 240 mg of caffeine and a 1-h dose of ~40 lx blue light in a non-athletic population. Twenty-one healthy subjects performed a computer-based psychomotor vigilance test before and after each of four randomly assigned trial conditions performed on different days: white light/placebo; white light/240 mg caffeine; blue light/placebo; blue light/240 mg caffeine. The Karolinska Sleepiness Scale was used to assess subjective measures of alertness. Both the caffeine only and blue light only conditions enhanced accuracy in a visual reaction test requiring a decision and an additive effect was observed with respect to the fastest reaction times. However, in a test of executive function, where a distraction was included, caffeine exerted a negative effect on accuracy. Furthermore, the blue light only condition consistently outperformed caffeine when both congruent and incongruent distractions were presented. The visual reactions in the absence of a decision or distraction were also enhanced in the blue light only condition and this effect was most prominent in the blue-eyed participants. Overall, blue light and caffeine demonstrated distinct effects on aspects of psychomotor function and have the potential to positively influence a range of settings where cognitive function and alertness are important. Specifically, despite the widespread use of caffeine in competitive sporting environments, the possible impact of blue light has received no research attention.

  3. Better to be red than blue in virtual competition

    DEFF Research Database (Denmark)

    Ilie, Andrei; Ioan, Silvia; Zagrean, Leon

    2008-01-01

    In the 2004 Olympic Games, opponents wearing red athletic uniforms were more likely to win against opponents wearing blue uniforms. To investigate whether this color bias extends to the world of virtual competition, we compared the performance of red and blue teams in a popular multiplayer first......-person-shooter (FPS) computer game. For 3 consecutive months, we collected data from a publicly available global statistics server. Outcomes from 1,347 matches played by the top 10 players on the same virtual arena were included. Red teams won 54.9% of matches, and this effect was highly significant. Our data suggest...... that joining the red team may offer a slight advantage over the blue team in virtual competition, and this should be accounted for when designing FPS games. It is likely that "seeing red" may trigger a powerful psychological distractor signal in human aggressive competition that can affect the outcome...

  4. Blue laser diode (450 nm) systems for welding copper

    Science.gov (United States)

    Silva Sa, M.; Finuf, M.; Fritz, R.; Tucker, J.; Pelaprat, J.-M.; Zediker, M. S.

    2018-02-01

    This paper will discuss the development of high power blue laser systems for industrial applications. The key development enabling high power blue laser systems is the emergence of high power, high brightness laser diodes at 450 nm. These devices have a high individual brightness rivaling their IR counterparts and they have the potential to exceed their performance and price barriers. They also have a very high To resulting in a 0.04 nm/°C wavelength shift. They have a very stable lateral far-field profile which can be combined with other diodes to achieve a superior brightness. This paper will report on the characteristics of the blue laser diodes, their integration into a modular laser system suitable for scaling the output power to the 1 kW level and beyond. Test results will be presented for welding of copper with power levels ranging from 150 Watts to 600 Watts

  5. Microanalysis study of archaeological mural samples containing Maya blue pigment

    International Nuclear Information System (INIS)

    Sanchez del Rio, M.; Martinetto, P.; Somogyi, A.; Reyes-Valerio, C.; Dooryhee, E.; Peltier, N.; Alianelli, L.; Moignard, B.; Pichon, L.; Calligaro, T.; Dran, J.-C.

    2004-01-01

    Elemental analysis by X-ray fluorescence and particle induced X-ray emission is applied to the study of several Mesoamerican mural samples containing blue pigments. The most characteristic blue pigment is Maya blue, a very stable organo-clay complex original from Maya culture and widely used in murals, pottery and sculptures in a vast region of Mesoamerica during the pre-hispanic time (from VIII century) and during the colonization until 1580. The mural samples come from six different archaeological sites (four pre-hispanic and two from XVI century colonial convents). The correlation between the presence of some elements and the pigment colour is discussed. From the comparative study of the elemental concentration, some conclusions are drawn on the nature of the pigments and the technology used

  6. Microanalysis study of archaeological mural samples containing Maya blue pigment

    Science.gov (United States)

    Sánchez del Río, M.; Martinetto, P.; Somogyi, A.; Reyes-Valerio, C.; Dooryhée, E.; Peltier, N.; Alianelli, L.; Moignard, B.; Pichon, L.; Calligaro, T.; Dran, J.-C.

    2004-10-01

    Elemental analysis by X-ray fluorescence and particle induced X-ray emission is applied to the study of several Mesoamerican mural samples containing blue pigments. The most characteristic blue pigment is Maya blue, a very stable organo-clay complex original from Maya culture and widely used in murals, pottery and sculptures in a vast region of Mesoamerica during the pre-hispanic time (from VIII century) and during the colonization until 1580. The mural samples come from six different archaeological sites (four pre-hispanic and two from XVI century colonial convents). The correlation between the presence of some elements and the pigment colour is discussed. From the comparative study of the elemental concentration, some conclusions are drawn on the nature of the pigments and the technology used.

  7. Microanalysis study of archaeological mural samples containing Maya blue pigment

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez del Rio, M. [ESRF, BP220, F-38043 Grenoble (France)]. E-mail: srio@esrf.fr; Martinetto, P. [Laboratoire de Cristallographie, CNRS, BP166 F-30842 Grenoble (France); Somogyi, A. [ESRF, BP220, F-38043 Grenoble (France); Reyes-Valerio, C. [INAH, Mexico DF (Mexico); Dooryhee, E. [Laboratoire de Cristallographie, CNRS, BP166 F-30842 Grenoble (France); Peltier, N. [Laboratoire de Cristallographie, CNRS, BP166 F-30842 Grenoble (France); Alianelli, L. [INFM-OGG c/o ESRF, BP220, F-38043 Grenoble Cedex (France); Moignard, B. [C2RMF, 6 Rue des Pyramides, F-75041 Paris Cedex 01 (France); Pichon, L. [C2RMF, 6 Rue des Pyramides, F-75041 Paris Cedex 01 (France); Calligaro, T. [C2RMF, 6 Rue des Pyramides, F-75041 Paris Cedex 01 (France); Dran, J.-C. [C2RMF, 6 Rue des Pyramides, F-75041 Paris Cedex 01 (France)

    2004-10-08

    Elemental analysis by X-ray fluorescence and particle induced X-ray emission is applied to the study of several Mesoamerican mural samples containing blue pigments. The most characteristic blue pigment is Maya blue, a very stable organo-clay complex original from Maya culture and widely used in murals, pottery and sculptures in a vast region of Mesoamerica during the pre-hispanic time (from VIII century) and during the colonization until 1580. The mural samples come from six different archaeological sites (four pre-hispanic and two from XVI century colonial convents). The correlation between the presence of some elements and the pigment colour is discussed. From the comparative study of the elemental concentration, some conclusions are drawn on the nature of the pigments and the technology used.

  8. Factors associated with blue-collar workers' risk perception of cardiovascular disease.

    Science.gov (United States)

    Hwang, Won Ju; Hong, Oisaeng; Kim, Mi Ja

    2012-12-01

    The purpose of this study was to investigate the contribution of actual cardiovascular disease (CVD) risk, as well as, individual, psychosocial, and work-related factors as predictors of CVD risk perception among Korean blue-collar workers. The participants were 238 Korean blue-collar workers who worked in small companies. Data were collected through a survey; anthropometric and blood pressure measures; and blood sampling for lipid levels. Blue-collar workers had high actual CVD risk and low CVD risk perception. The significant predictors of risk perception included perceived health status, alcohol consumption, knowledge of CVD risk, actual CVD risk, decision latitude, and shift work. The model explained 26% of the variance in CVD risk perception. The result suggests when occupational health nurses are giving routine health examination in small companies, they can enhance CVD risk perception in blue-collar workers by providing essential information about CVD risk factors and personal counseling on the individual worker's CVD risk status.

  9. Reduction of molybdate to molybdenum blue by Klebsiella sp. strain hkeem.

    Science.gov (United States)

    Lim, H K; Syed, M A; Shukor, M Y

    2012-06-01

    A novel molybdate-reducing bacterium, tentatively identified as Klebsiella sp. strain hkeem and based on partial 16s rDNA gene sequencing and phylogenetic analysis, has been isolated. Strain hkeem produced 3 times more molybdenum blue than Serratia sp. strain Dr.Y8; the most potent Mo-reducing bacterium isolated to date. Molybdate was optimally reduced to molybdenum blue using 4.5 mM phosphate, 80 mM molybdate and using 1% (w/v) fructose as a carbon source. Molybdate reduction was optimum at 30 °C and at pH 7.3. The molybdenum blue produced from cellular reduction exhibited absorption spectrum with a maximum peak at 865 nm and a shoulder at 700 nm. Inhibitors of electron transport system such as antimycin A, rotenone, sodium azide, and potassium cyanide did not inhibit the molybdenum-reducing enzyme. Mercury, silver, and copper at 1 ppm inhibited molybdenum blue formation in whole cells of strain hkeem. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Origin of the blue emissions of polyacetylenes bearing carbazole side groups

    International Nuclear Information System (INIS)

    Huang Yuanming; Song Yibing; Huang Chong; Zhou Xueping; Ouyang Yandong; Ge Weikun; Lam, Jacky W.Y.; Tang Benzhong

    2005-01-01

    The optical properties and electronic structures of one mono-substituted polyacetylene and two di-substituted polyacetylenes have been investigated. Each of the substituted polyacetylenes bears a carbazole unit in the side chain. In spite of the differences in their molecular structures, the dilute solutions (∼1x10 -6 M) of these substituted polyacetylenes exhibit the same absorptions and the same deep-blue emissions (∼360 nm). Interestingly, the absorption and emission spectra of these substituted polyacetylenes are similar to those of the small molecule carbazole. As the concentration of the substituted polyacetylenes increases to about 1x10 -3 M, we have detected intense blue emissions at about 475 nm. Using Hueckel tight binding programs, we have calculated the electronic structures of the carbazole-containing polyacetylenes. Our results indicate that the absorption, the deep-blue emission (∼360 nm) and the intense blue emission (∼475 nm) originate from the carbazole chromophores in the side chain

  11. Improved power efficiency of blue fluorescent organic light-emitting diode with intermixed host structure

    Energy Technology Data Exchange (ETDEWEB)

    Yue, Shouzhen; Zhang, Shiming; Zhang, Zhensong; Wu, Yukun; Wang, Peng; Guo, Runda; Chen, Yu; Qu, Dalong; Wu, Qingyang; Zhao, Yi, E-mail: yizhao@jlu.edu.cn; Liu, Shiyong

    2013-11-15

    High power efficiency (PE) p-bis(p-N,N-diphenyl-aminostyryl)benzene (DSA-ph) based fluorescent blue organic light-emitting diode (OLED) is demonstrated by utilizing intermixed host (IH) structure. The PE outperforms those devices based on single host (SH), mixed host (MH), and double emitting layers (DELs). By further optimizing the intermixed layer, peak PE of the IH device is increased up to 8.7 lm/W (1.7 times higher than conventional SH device), which is the highest value among the DSA-ph based blue device reported so far. -- Highlights: • DSA-ph based blue fluorescent OLEDs are fabricated. • The intermixed host structure is first introduced into the blue devices. • Blue device with the highest power efficiency based on DSA-ph is obtained.

  12. Electronic structures and enhanced optical properties of blue phosphorene/transition metal dichalcogenides van der Waals heterostructures

    Science.gov (United States)

    Peng, Qiong; Wang, Zhenyu; Sa, Baisheng; Wu, Bo; Sun, Zhimei

    2016-01-01

    As a fast emerging topic, van der Waals (vdW) heterostructures have been proposed to modify two-dimensional layered materials with desired properties, thus greatly extending the applications of these materials. In this work, the stacking characteristics, electronic structures, band edge alignments, charge density distributions and optical properties of blue phosphorene/transition metal dichalcogenides (BlueP/TMDs) vdW heterostructures were systematically studied based on vdW corrected density functional theory. Interestingly, the valence band maximum and conduction band minimum are located in different parts of BlueP/MoSe2, BlueP/WS2 and BlueP/WSe2 heterostructures. The MoSe2, WS2 or WSe2 layer can be used as the electron donor and the BlueP layer can be used as the electron acceptor. We further found that the optical properties under visible-light irradiation of BlueP/TMDs vdW heterostructures are significantly improved. In particular, the predicted upper limit energy conversion efficiencies of BlueP/MoS2 and BlueP/MoSe2 heterostructures reach as large as 1.16% and 0.98%, respectively, suggesting their potential applications in efficient thin-film solar cells and optoelectronic devices. PMID:27553787

  13. Electronic structures and enhanced optical properties of blue phosphorene/transition metal dichalcogenides van der Waals heterostructures.

    Science.gov (United States)

    Peng, Qiong; Wang, Zhenyu; Sa, Baisheng; Wu, Bo; Sun, Zhimei

    2016-08-24

    As a fast emerging topic, van der Waals (vdW) heterostructures have been proposed to modify two-dimensional layered materials with desired properties, thus greatly extending the applications of these materials. In this work, the stacking characteristics, electronic structures, band edge alignments, charge density distributions and optical properties of blue phosphorene/transition metal dichalcogenides (BlueP/TMDs) vdW heterostructures were systematically studied based on vdW corrected density functional theory. Interestingly, the valence band maximum and conduction band minimum are located in different parts of BlueP/MoSe2, BlueP/WS2 and BlueP/WSe2 heterostructures. The MoSe2, WS2 or WSe2 layer can be used as the electron donor and the BlueP layer can be used as the electron acceptor. We further found that the optical properties under visible-light irradiation of BlueP/TMDs vdW heterostructures are significantly improved. In particular, the predicted upper limit energy conversion efficiencies of BlueP/MoS2 and BlueP/MoSe2 heterostructures reach as large as 1.16% and 0.98%, respectively, suggesting their potential applications in efficient thin-film solar cells and optoelectronic devices.

  14. Treatment of attention deficit hyperactivity disorder insomnia with blue wavelength light-blocking glasses

    Directory of Open Access Journals (Sweden)

    Fargason RE

    2013-01-01

    Full Text Available Rachel E Fargason, Taylor Preston, Emily Hammond, Roberta May, Karen L GambleDepartment of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham School of Medicine, Birmingham, AL, USABackground: The aim of this study was to examine a nonmedical treatment alternative to medication in attention deficit hyperactivity disorder (ADHD insomnia, in which blue wavelength light-blocking glasses are worn during the evening hours to counteract the phase-delaying effect of light. Outcome measures included sleep quality and midsleep time. The capacity of ADHD subjects to comply with treatment using the glasses was assessed.Methods: Daily bedtime, wake-up time, and compliance diaries were used to assess sleep quality and timing during a baseline observation week and a 2-week intervention period. The Pittsburgh Sleep Quality Index (PSQI was administered following baseline and intervention. The intervention protocol consisted of use of blue wavelength-blocking glasses and a moderate lighting environment during evening hours.Results: Partial and variable compliance were noted, with only 14 of 22 subjects completing the study due to nonadherence with wearing the glasses and diary completion. Despite the minimum 3-hour recommendation, glasses were worn, on average, for 2.4 hours daily. Lighting was reduced for only 58.7% of the evening. Compared with baseline, the intervention resulted in significant improvement in global PSQI scores, PSQI subcomponent scores, and sleep diary measures of morning refreshment after sleep (P = 0.037 and night-time awakenings (P = 0.015. Global PSQI scores fell from 11.15 to 4.54, dropping below the cut-off score of 5 for clinical insomnia. The more phase-delayed subjects, ie, those with an initial midsleep time after 4:15 am, trended towards an earlier midsleep time by 43.2 minutes following the intervention (P = 0.073. Participants reported less anxiety following the intervention (P = 0.048.Conclusions

  15. The different star formation histories of blue and red spiral and elliptical galaxies

    Science.gov (United States)

    Tojeiro, Rita; Masters, Karen L.; Richards, Joshua; Percival, Will J.; Bamford, Steven P.; Maraston, Claudia; Nichol, Robert C.; Skibba, Ramin; Thomas, Daniel

    2013-06-01

    We study the spectral properties of intermediate mass galaxies (M* ˜ 1010.7 M⊙) as a function of colour and morphology. We use Galaxy Zoo to define three morphological classes of galaxies, namely early types (ellipticals), late-type (disc-dominated) face-on spirals and early-type (bulge-dominated) face-on spirals. We classify these galaxies as blue or red according to their Sloan Digital Sky Survey (SDSS) g - r colour and use the spectral fitting code Versatile Spectral Analyses to calculate time-resolved star formation histories, metallicity and total starlight dust extinction from their SDSS fibre spectra. We find that red late-type spirals show less star formation in the last 500 Myr than blue late-type spirals by up to a factor of 3, but share similar star formation histories at earlier times. This decline in recent star formation explains their redder colour: their chemical and dust content are the same. We postulate that red late-type spirals are recent descendants of blue late-type spirals, with their star formation curtailed in the last 500 Myr. The red late-type spirals are however still forming stars ≃17 times faster than red ellipticals over the same period. Red early-type spirals lie between red late-type spirals and red ellipticals in terms of recent-to-intermediate star formation and dust content. Therefore, it is plausible that these galaxies represent an evolutionary link between these two populations. They are more likely to evolve directly into red ellipticals than red late-type spirals, which show star formation histories and dust content closer to blue late-type spirals. Blue ellipticals show similar star formation histories as blue spirals (regardless of type), except that they have formed less stars in the last 100 Myr. However, blue ellipticals have different dust content, which peaks at lower extinction values than all spiral galaxies. Therefore, many blue ellipticals are unlikely to be descendants of blue spirals, suggesting there may

  16. MANAJEMEN PENDIDIKAN TINGGI ISLAM DALAM SPEKTRUM BLUE OCEAN STRATEGY

    Directory of Open Access Journals (Sweden)

    Mardia Mardia

    2011-06-01

    Full Text Available Abstract: The Islamic higher educations are undergoing important changes involving the development of missions and reorganization of management, with implications for their quality education in the midst of complexity. The main study of this article highlights the importance of governance quality in Islamic higher education in the face of complexity from the perspective of Blue Ocean Strategy. It can be concluded that to win in the future, Islamic higher educations must stop competing each other. The only way to beat the competition is to stop trying to beat the competition. Blue Ocean Strategy to be one of the alternatives in the management of educational institutions to create distinctive adavantage and competitiveness based graduates. Abstrak:  Pendidikan tinggi Islam mengalami perubahan signifikan pada pengembangan misi dan reorganisasi manajemen yang mempengaruhi kualitas pendidikan di era kompleksitas. Kompleksitas tersebut tidak dapat diprediksi dan mempengaruhi munculnya gejala disorientasi nilai, disharmoni sosial, dan peran disfungsional. Pokok kajian tulisan ini menyorot pentingnya tatakelola pendidikan tinggi Islam bermutu dalam perspektif Blue Ocean Strategy dalam menghadapi kompleksitas. Pendekatan yang digunakan adalah analisis deskriptif teoritis dan praktis. Temuan penelitian adalah untuk berdaya saing di masa depan, pendidikan tinggi Islam harus berhenti bersaing satu sama lain. Satu-satunya cara untuk mengalahkan kompetisi adalah berhenti berusaha memenangi kompetisi. Blue Ocean Strategy menjadi salah satu alternatif dalam pengelolaan lembaga pendidikan dalam mencetak lulusan yang kompetitif dan unggul.

  17. Inhibitory effect of blue light emitting diode on migration and invasion of cancer cells.

    Science.gov (United States)

    Oh, Phil-Sun; Kim, Hyun-Soo; Kim, Eun-Mi; Hwang, Hyosook; Ryu, Hyang Hwa; Lim, SeokTae; Sohn, Myung-Hee; Jeong, Hwan-Jeong

    2017-12-01

    The aim of this study was to determine the effects and molecular mechanism of blue light emitting diode (LED) in tumor cells. A migration and invasion assay for the metastatic behavior of mouse colon cancer CT-26 and human fibrosarcoma HT-1080 cells was performed. Cancer cell migration-related proteins were identified by obtaining a 2-dimensional gel electrophoresis (2-DE) in total cellular protein profile of blue LED-irradiated cancer cells, followed by matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) analysis of proteins. Protein levels were examined by immunoblotting. Irradiation with blue LED inhibited CT-26 and HT-1080 cell migration and invasion. The anti-metastatic effects of blue LED irradiation were associated with inhibition of matrix metalloproteinase (MMP)-2 and MMP-9 expression. P38 MAPK phosphorylation was increased in blue LED-irradiated CT-26 and HT-1080 cells, but was inhibited after pretreatment with SB203580, a specific inhibitor of p38 MAPK. Inhibition of p38 MAPK phosphorylation by SB203580 treatment increased number of migratory cancer cells in CT-26 and HT-1080 cells, indicating that blue LED irradiation inhibited cancer cell migration via phosphorylation of p38 MAPK. Additionally blue LED irradiation of mice injected with CT-26 cells expressing luciferase decreased early stage lung metastasis compared to untreated control mice. These results indicate that blue LED irradiation inhibits cancer cell migration and invasion in vitro and in vivo. © 2017 Wiley Periodicals, Inc.

  18. Profuse activity of blue electrical discharges at the tops of thunderstorms

    DEFF Research Database (Denmark)

    Chanrion, Olivier; Neubert, Torsten; Mogensen, Andreas

    2017-01-01

    . The emissions are related to the so-called blue jets, blue starters and possibly pixies. The observations are the first of their kind and give a new perspective on the electrical activity at the top of tropical thunderstorms; further, they underscore that thunderstorm discharges directly perturb the chemistry...

  19. Blue laser diode (LD) and light emitting diode (LED) applications

    International Nuclear Information System (INIS)

    Bergh, Arpad A.

    2004-01-01

    The family of blue LEDs, edge emitting and surface emitting lasers, enable a number of applications. Blue lasers are used in digital applications such as optical storage in high density DVDs. The resolution of the spot size and hence the storage density is diffraction limited and is inversely proportional to the square of the wavelength of the laser. Other applications include printing, optical scanners, and high-resolution photo-lithography. As light emitters, blue LEDs are used for signaling and in direct view large area emissive displays. They are also making inroads into signage and LCD back-lighting, mobile platforms, and decorative accent lighting in curtains, furniture, etc. Blue LEDs produce white light either with phosphor wavelength converters or in combination with red and green LEDs. The full potential of LED light sources will require three devices to enable complete control over color and intensity. Sensing and medical/bio applications have a major impact on home security, on monitoring the environment, and on health care. New emerging diagnostic and therapeutic applications will improve the quality and reduce the cost of health care. (copyright 2004 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  20. Blue laser diode (LD) and light emitting diode (LED) applications

    Energy Technology Data Exchange (ETDEWEB)

    Bergh, Arpad A [Optoelectronics Industry Development Association (OIDA), 1133 Connecticut Avenue, NW, Suite 600, Washington, DC 20036-4329 (United States)

    2004-09-01

    The family of blue LEDs, edge emitting and surface emitting lasers, enable a number of applications. Blue lasers are used in digital applications such as optical storage in high density DVDs. The resolution of the spot size and hence the storage density is diffraction limited and is inversely proportional to the square of the wavelength of the laser. Other applications include printing, optical scanners, and high-resolution photo-lithography. As light emitters, blue LEDs are used for signaling and in direct view large area emissive displays. They are also making inroads into signage and LCD back-lighting, mobile platforms, and decorative accent lighting in curtains, furniture, etc. Blue LEDs produce white light either with phosphor wavelength converters or in combination with red and green LEDs. The full potential of LED light sources will require three devices to enable complete control over color and intensity. Sensing and medical/bio applications have a major impact on home security, on monitoring the environment, and on health care. New emerging diagnostic and therapeutic applications will improve the quality and reduce the cost of health care. (copyright 2004 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  1. Blue light potentiates neurogenesis induced by retinoic acid-loaded responsive nanoparticles.

    Science.gov (United States)

    Santos, Tiago; Ferreira, Raquel; Quartin, Emanuel; Boto, Carlos; Saraiva, Cláudia; Bragança, José; Peça, João; Rodrigues, Cecília; Ferreira, Lino; Bernardino, Liliana

    2017-09-01

    Neurogenic niches constitute a powerful endogenous source of new neurons that can be used for brain repair strategies. Neuronal differentiation of these cells can be regulated by molecules such as retinoic acid (RA) or by mild levels of reactive oxygen species (ROS) that are also known to upregulate RA receptor alpha (RARα) levels. Data showed that neural stem cells from the subventricular zone (SVZ) exposed to blue light (405nm laser) transiently induced NADPH oxidase-dependent ROS, resulting in β-catenin activation and neuronal differentiation, and increased RARα levels. Additionally, the same blue light stimulation was capable of triggering the release of RA from light-responsive nanoparticles (LR-NP). The synergy between blue light and LR-NP led to amplified neurogenesis both in vitro and in vivo, while offering a temporal and spatial control of RA release. In conclusion, this combinatory treatment offers great advantages to potentiate neuronal differentiation, and provides an innovative and efficient application for brain regenerative therapies. Controlling the differentiation of stem cells would support the development of promising brain regenerative therapies. Blue light transiently increased reactive oxygen species, resulting in neuronal differentiation and increased retinoic acid receptor (RARα) levels. Additionally, the same blue light stimulation was capable of triggering the release of RA from light-responsive nanoparticles (LR-NP). The synergy between blue light and LR-NP led to amplified neurogenesis, while offering a temporal and spatial control of RA release. In this sense, our approach relying on the modulation of endogenous stem cells for the generation of new neurons may support the development of novel clinical therapies. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  2. Blue green component and integrated urban design

    Directory of Open Access Journals (Sweden)

    Stanković Srđan M.

    2016-01-01

    Full Text Available This paper aims to demonstrate the hidden potential of blue green components, in a synergetic network, not as separate systems, like used in past. The innovative methodology of the project Blue Green Dream is presented through examples of good practice. A new approach in the project initiate thoughtful planning and remodeling of the settlement for the modern man. Professional and scientific public is looking for way to create more healthy and stimulating place for living. However, offered integrative solutions still remain out of urban and architectural practice. Tested technologies in current projects confirmed measurability of innovative approaches and lessons learned. Scientific and professional contributions are summarized in master's and doctoral theses that have been completed or are in process of writing.

  3. The effect of provider control of Blue Shield plans on health care markets.

    Science.gov (United States)

    Arnould, R J; DeBrock, L M

    1985-07-01

    Blue Shield plans often are granted regulatory advantages by the states in which they operate. Run efficiently, such not-for-profit firms should use these lower costs to eliminate their less advantaged rivals, the commercial insurers. However, these higher-cost commercial providers have been able to offer insurance coverage at prices competitive with the Blues, as evidenced by the fact that Blue plans have, on average, less than 50 percent market share. Similar prices with lower overall costs implies that economic rents are being earned, rents which a not-for-profit firm cannot distribute to owners. In this paper we argue that when there are competing goals among the groups controlling the Blue Shield plans, the different possible "uses" of the regulatory advantage become endogenously determined, necessitating the use of simultaneous equation estimation. Testing this model we find the major effect of doctor-control of Blue Shield plans is to raise doctors' fees while lowering the amount of rents captured by both consumers and administrators.

  4. Study of extraction-spectrophotometric micro-determination of boron with methylene blue and its application

    International Nuclear Information System (INIS)

    Zhu Daohong

    1990-08-01

    A sensitive extraction-spectrophotometric method for microdetermination of boron with methylene blue was investigated. The method was based on the extraction of a BF 4 - -methylene blue complex into dichloroethane. Boron was determined directly by measuring the absorbance at 658 nm. The calibration graph was linear over the range of 2.5 x 10 -9 to 8 x 10 -8 g/mL. The blank, mechanism of the reactions, interference of other ions and some optimum conditions of the method were studied in detail. The main source of the blank resulted from methylene blue and the complex of F - -methylene blue. In order to reduce the blank, the amounts of methylene blue, H 2 SO 4 and HF were used as less as possible. Only one to one complex BF 4 - -methylene blue was formed in the medium of H 2 SO 4 . About 90% of methylene blue and F - -methylene blue complex was removre with 5 ml of water and only a little amount of BF 4 -methylene blue complex was decomposed. The extraction-spectrophotometric method with methylene blue was first applied to the microdetermination of boron in sodium metal and UF 6 . The sample of sodium metal was taken and weighed in the glovebox filled with argon. Then sodium metal was oxidized, hydrolyzed, netralized and fluorizated with H 2 O, H 2 SO 4 and HF, respectively. The 0.5 ppm of boron in sodium metal was determined with a relative error about ±4%. This method can be applied to the determination of boron in sodium metal, sodium sulfate and sodium hydroxide at diffeent grades. The species of boron in the hydrolysate of UF 6 is BF 4 - anion, so the sample can be directly analyzed. Boron contents in the range of 0.1 to 0.5 ppm was determined with a relative error about ±3%. Six samples could be analysed in 2h

  5. Prussian blue caged in spongiform adsorbents using diatomite and carbon nanotubes for elimination of cesium.

    Science.gov (United States)

    Hu, Baiyang; Fugetsu, Bunshi; Yu, Hongwen; Abe, Yoshiteru

    2012-05-30

    We developed a spongiform adsorbent that contains Prussian blue, which showed a high capacity for eliminating cesium. An in situ synthesizing approach was used to synthesize Prussian blue inside diatomite cavities. Highly dispersed carbon nanotubes (CNTs) were used to form CNT networks that coated the diatomite to seal in the Prussian blue particles. These ternary (CNT/diatomite/Prussian-blue) composites were mixed with polyurethane (PU) prepolymers to produce a quaternary (PU/CNT/diatomite/Prussian-blue), spongiform adsorbent with an in situ foaming procedure. Prussian blue was permanently immobilized in the cell walls of the spongiform matrix and preferentially adsorbed cesium with a theoretical capacity of 167 mg/g cesium. Cesium was absorbed primarily by an ion-exchange mechanism, and the absorption was accomplished by self-uptake of radioactive water by the quaternary spongiform adsorbent. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Methylene Blue to Treat Protamine-induced Anaphylaxis Reactions. An Experimental Study in Pigs

    Directory of Open Access Journals (Sweden)

    Agnes Afrodite S. Albuquerque

    Full Text Available ABSTRACT Objective: To examine if methylene blue (MB can counteract or prevent protamine (P cardiovascular effects. Methods: The protocol included five heparinized pig groups: Group Sham -without any drug; Group MB - MB 3 mg/kg infusion; Group P - protamine; Group P/MB - MB after protamine; Group MB/P - MB before protamine. Nitric oxide levels were obtained by the nitric oxide/ozone chemiluminescence method, performed using the Nitric Oxide Analizer 280i (Sievers, Boulder, CO, USA. Malondialdehyde plasma levels were estimated using the thiobarbiturate technique. Results: 1 Groups Sham and MB presented unchanged parameters; 2 Group P - a Intravenous protamine infusion caused mean arterial pressure decrease and recovery trend after 25-30 minutes, b Cardiac output decreased and remained stable until the end of protamine injection, and c Sustained systemic vascular resistance increased until the end of protamine injection; 3 Methylene blue infusion after protamine (Group P/MB - a Marked mean arterial pressure decreased after protamine, but recovery after methylene blue injection, b Cardiac output decreased after protamine infusion, recovering after methylene blue infusion, and c Sustained systemic vascular resistance increased after protamine infusion and methylene blue injections; 4 Methylene blue infusion before protamine (Group MB/P - a Mean arterial pressure decrease was less severe with rapid recovery, b After methylene blue, there was a progressive cardiac output increase up to protamine injection, when cardiac output decreased, and c Sustained systemic vascular resistance decreased after protamine, followed by immediate Sustained systemic vascular resistance increase; 5 Plasma nitrite/nitrate and malondialdehyde values did not differ among the experimental groups. Conclusion: Reviewing these experimental results and our clinical experience, we suggest methylene blue safely prevents and treats hemodynamic protamine complications, from the

  7. Age and sex dimorphism in the Canary Blue Tit Cyanistes teneriffae ...

    African Journals Online (AJOL)

    The Canary Blue Tit Cyanistes teneriffae has recently been split off from the Common Blue Tit Cyanistes caeruleus as a separate species. Live biometrics from across the entire distribution on the island of Tenerife (subspecies teneriffae teneriffae) are reported. Results suggest that first-year birds had similar bill shape to ...

  8. Intradermal Alcian-Blue Injection Method to Trace Acupuncture Meridians

    Directory of Open Access Journals (Sweden)

    Baeckkyoung Sung

    2008-06-01

    Full Text Available Objective : In this article, we report on the intradermal Alcian blue staining method for tracing the meridians of acupuncture. Methods : 1% Alcian blue solution was injected into acupoints by using a 0.5mL insulin syringe with a 31-gauge needle, then the skin was incised and was observed under a stereoscopic microscope. The specimens were examined by using immunohistochemical methods and were observed under a confocal laser scanning microscope. Results : A threadlike structure, which was visualized with Alcian blue, existed in dermis layer and proceeded to hypodermis. In this structure, characteristic alignments of rod- shaped nuclei and 1-2μm sized DNA granules were observed. Furthermore, abundant blood capillary plexuses, peripheral nerve endings, and a corpusclelike structure(about 300μm in diameter were visualized in the skin tissues of acupoints. Conclusion : It was concluded that the specific threadlike and corpuscle-like structures corresponded to superficial Bonghan duct and corpuscle, respectively.

  9. T's and Blues. Specialized Information Service.

    Science.gov (United States)

    Do It Now Foundation, Phoenix, AZ.

    This compilation of journal articles provides basic information on abuse of Talwin, a mild prescription painkiller (T's), and Pyribenzamine, a nonprescription antihistimine (Blues). These two drugs, taken in combination, produce an effect similar to that produced by heroin. Stories from "Drug Survival News,""Emergency…

  10. Blue lighting accelerates post-stress relaxation: Results of a preliminary study.

    Science.gov (United States)

    Minguillon, Jesus; Lopez-Gordo, Miguel Angel; Renedo-Criado, Diego A; Sanchez-Carrion, Maria Jose; Pelayo, Francisco

    2017-01-01

    Several authors have studied the influence of light on both human physiology and emotions. Blue light has been proved to reduce sleepiness by suppression of melatonin secretion and it is also present in many emotion-related studies. Most of these have a common lack of objective methodology since results and conclusions are based on subjective perception of emotions. The aim of this work was the objective assessment of the effect of blue lighting in post-stress relaxation, in comparison with white lighting, by means of bio-signals and standardized procedures. We conducted a study in which twelve healthy volunteers were stressed and then performed a relaxation session within a chromotherapy room with blue (test group) or white (control group) lighting. We conclude that the blue lighting accelerates the relaxation process after stress in comparison with conventional white lighting. The relaxation time decreased by approximately three-fold (1.1 vs. 3.5 minutes). We also observed a convergence time (3.5-5 minutes) after which the advantage of blue lighting disappeared. This supports the relationship between color of light and stress, and the observations reported in previous works. These findings could be useful in clinical and educational environments, as well as in daily-life context and emerging technologies such as neuromarketing. However, our study must be extended to draw reliable conclusions and solid scientific evidence.

  11. Blue lighting accelerates post-stress relaxation: Results of a preliminary study.

    Directory of Open Access Journals (Sweden)

    Jesus Minguillon

    Full Text Available Several authors have studied the influence of light on both human physiology and emotions. Blue light has been proved to reduce sleepiness by suppression of melatonin secretion and it is also present in many emotion-related studies. Most of these have a common lack of objective methodology since results and conclusions are based on subjective perception of emotions. The aim of this work was the objective assessment of the effect of blue lighting in post-stress relaxation, in comparison with white lighting, by means of bio-signals and standardized procedures. We conducted a study in which twelve healthy volunteers were stressed and then performed a relaxation session within a chromotherapy room with blue (test group or white (control group lighting. We conclude that the blue lighting accelerates the relaxation process after stress in comparison with conventional white lighting. The relaxation time decreased by approximately three-fold (1.1 vs. 3.5 minutes. We also observed a convergence time (3.5-5 minutes after which the advantage of blue lighting disappeared. This supports the relationship between color of light and stress, and the observations reported in previous works. These findings could be useful in clinical and educational environments, as well as in daily-life context and emerging technologies such as neuromarketing. However, our study must be extended to draw reliable conclusions and solid scientific evidence.

  12. Human Blue Cone Opsin Regeneration Involves Secondary Retinal Binding with Analog Specificity.

    Science.gov (United States)

    Srinivasan, Sundaramoorthy; Fernández-Sampedro, Miguel A; Morillo, Margarita; Ramon, Eva; Jiménez-Rosés, Mireia; Cordomí, Arnau; Garriga, Pere

    2018-03-27

    Human color vision is mediated by the red, green, and blue cone visual pigments. Cone opsins are G-protein-coupled receptors consisting of an opsin apoprotein covalently linked to the 11-cis-retinal chromophore. All visual pigments share a common evolutionary origin, and red and green cone opsins exhibit a higher homology, whereas blue cone opsin shows more resemblance to the dim light receptor rhodopsin. Here we show that chromophore regeneration in photoactivated blue cone opsin exhibits intermediate transient conformations and a secondary retinoid binding event with slower binding kinetics. We also detected a fine-tuning of the conformational change in the photoactivated blue cone opsin binding site that alters the retinal isomer binding specificity. Furthermore, the molecular models of active and inactive blue cone opsins show specific molecular interactions in the retinal binding site that are not present in other opsins. These findings highlight the differential conformational versatility of human cone opsin pigments in the chromophore regeneration process, particularly compared to rhodopsin, and point to relevant functional, unexpected roles other than spectral tuning for the cone visual pigments. Copyright © 2018 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  13. Discovery of a blue whale feeding and nursing ground in southern Chile.

    Science.gov (United States)

    Hucke-Gaete, Rodrigo; Osman, Layla P; Moreno, Carlos A; Findlay, Ken P; Ljungblad, Don K

    2004-05-07

    After the extensive exploitation that reduced the Southern Hemisphere blue whale (Balaenoptera musculus) populations to less than 3% of its original numbers, studies on its recovery have been compounded by the inaccessibility of most populations and the extensive migrations between low and high latitudes, thus ensuring that knowledge about blue whale ecology and status remains limited. We report the recent discovery of, arguably, the most important blue whale feeding and nursing ground known to date in the Southern Hemisphere, which is located near the fjords off southern Chile. Through aerial and marine surveys (n = 7) 47 groups, comprising 153 blue whales including at least 11 mother-calf pairs, were sighted during the austral summer and early autumn of 2003. The implications of this discovery on the biological understanding and conservation of this endangered species are discussed.

  14. WS1: one more new Galactic bona fide luminous blue variable★

    Science.gov (United States)

    Kniazev, A. Y.; Gvaramadze, V. V.; Berdnikov, L. N.

    2015-04-01

    In this Letter, we report the results of spectroscopic and photometric monitoring of the candidate luminous blue variable (LBV) WS1, which was discovered in 2011 through the detection of a mid-infrared circular shell and follow-up optical spectroscopy of its central star. Our monitoring showed that WS1 brightened in the B, V and I bands by more than 1 mag during the last three years, while its spectrum revealed dramatic changes during the same time period, indicating that the star became much cooler. The light curve of WS1 demonstrates that the brightness of this star has reached maximum in 2013 December and then starts to decline. These findings unambiguously proved the LBV nature of WS1 and added one more member to the class of Galactic bona fide LBVs, bringing their number to sixteen (an updated census of these objects is provided).

  15. Performance of Fluidized bed Fenton process in Degrading Acid Blue 113

    Science.gov (United States)

    Bello, M. M.; Raman, A. A.

    2017-06-01

    The performance of a fluidized bed Fenton process in degrading Acid Blue 113 (AB 113) was investigated. Fluidized bed Fenton process is a modification of conventional Fenton oxidation, aimed at reducing sludge generation and improving process performance. Response surface methodology was used to study the effects of operational parameter on the color removal from the dye. Dimensionless factors, Dye/Fe2+, H2O2/Fe2+ and pH were used as the independent variables in Box-Behnken Design (BDD). Reduced quadratic model was developed to predict the color removal. The process could remove up to 99 % of the initial color. The most significant factor for color removal was found to be Dye/Fe2+, followed by H2O2/Fe2+. Unlike conventional Fenton, the initial pH of the solution does not have a significant effect on the color removal.

  16. Application of Blue Ocean Strategy to Chinese 3G Mobile Telecom Industry

    OpenAIRE

    Wang, Zang; Yang, Jin Wei

    2010-01-01

    The purpose of this study was to apply “Blue Ocean” strategy to Chinese 3G mobile telecom industry. Chinese 3G mobile telecom industry is a rapidly growing multiple industry which served a lot of services to customers. The thesis tries to find whether all services are important to Chinese 3G operators’ competiveness and how to create a blue ocean for Chinese 3G operators, help Chinese 3G operators to find their core service from the customers’ opinion and create a new blue ocean industry of m...

  17. Stroemgren and BV photometry of potential halo blue horizontal branch field stars

    Energy Technology Data Exchange (ETDEWEB)

    Flynn, C; Sommer-Larsen, J

    1988-11-01

    Stroemgren four-colour and broadband BV photoelectric photometry has been obtained for a sample of potential halo blue horizontal branch stars in two high galactic latitude fields. The large majority of the stars observed are classified as blue horizontal branch stars on the basis of two different surface gravity indicators. Measurements of Ca K-line equivalent widths from medium-dispersion spectra of the stars confirm that most are Population II objects. No metal-rich A-stars were found beyond a few kpc from the galactic disc in the study of faint blue stars.

  18. Carotenoid metabolic profiling and transcriptome-genome mining reveal functional equivalence among blue-pigmented copepods and appendicularia

    KAUST Repository

    Mojib, Nazia; Amad, Maan H.; Thimma, Manjula; Aldanondo, Naroa; Kumaran, Mande; Irigoien, Xabier

    2014-01-01

    The tropical oligotrophic oceanic areas are characterized by high water transparency and annual solar radiation. Under these conditions, a large number of phylogenetically diverse mesozooplankton species living in the surface waters (neuston) are found to be blue pigmented. In the present study, we focused on understanding the metabolic and genetic basis of the observed blue phenotype functional equivalence between the blue-pigmented organisms from the phylum Arthropoda, subclass Copepoda (Acartia fossae) and the phylum Chordata, class Appendicularia (Oikopleura dioica) in the Red Sea. Previous studies have shown that carotenoid–protein complexes are responsible for blue coloration in crustaceans. Therefore, we performed carotenoid metabolic profiling using both targeted and nontargeted (high-resolution mass spectrometry) approaches in four different blue-pigmented genera of copepods and one blue-pigmented species of appendicularia. Astaxanthin was found to be the principal carotenoid in all the species. The pathway analysis showed that all the species can synthesize astaxanthin from β-carotene, ingested from dietary sources, via 3-hydroxyechinenone, canthaxanthin, zeaxanthin, adonirubin or adonixanthin. Further, using de novo assembled transcriptome of blue A. fossae (subclass Copepoda), we identified highly expressed homologous β-carotene hydroxylase enzymes and putative carotenoid-binding proteins responsible for astaxanthin formation and the blue phenotype. In blue O. dioica (class Appendicularia), corresponding putative genes were identified from the reference genome. Collectively, our data provide molecular evidences for the bioconversion and accumulation of blue astaxanthin–protein complexes underpinning the observed ecological functional equivalence and adaptive convergence among neustonic mesozooplankton.

  19. Carotenoid metabolic profiling and transcriptome-genome mining reveal functional equivalence among blue-pigmented copepods and appendicularia

    KAUST Repository

    Mojib, Nazia

    2014-06-01

    The tropical oligotrophic oceanic areas are characterized by high water transparency and annual solar radiation. Under these conditions, a large number of phylogenetically diverse mesozooplankton species living in the surface waters (neuston) are found to be blue pigmented. In the present study, we focused on understanding the metabolic and genetic basis of the observed blue phenotype functional equivalence between the blue-pigmented organisms from the phylum Arthropoda, subclass Copepoda (Acartia fossae) and the phylum Chordata, class Appendicularia (Oikopleura dioica) in the Red Sea. Previous studies have shown that carotenoid–protein complexes are responsible for blue coloration in crustaceans. Therefore, we performed carotenoid metabolic profiling using both targeted and nontargeted (high-resolution mass spectrometry) approaches in four different blue-pigmented genera of copepods and one blue-pigmented species of appendicularia. Astaxanthin was found to be the principal carotenoid in all the species. The pathway analysis showed that all the species can synthesize astaxanthin from β-carotene, ingested from dietary sources, via 3-hydroxyechinenone, canthaxanthin, zeaxanthin, adonirubin or adonixanthin. Further, using de novo assembled transcriptome of blue A. fossae (subclass Copepoda), we identified highly expressed homologous β-carotene hydroxylase enzymes and putative carotenoid-binding proteins responsible for astaxanthin formation and the blue phenotype. In blue O. dioica (class Appendicularia), corresponding putative genes were identified from the reference genome. Collectively, our data provide molecular evidences for the bioconversion and accumulation of blue astaxanthin–protein complexes underpinning the observed ecological functional equivalence and adaptive convergence among neustonic mesozooplankton.

  20. The blue water footprint of electricity from hydropower

    Directory of Open Access Journals (Sweden)

    M. M. Mekonnen

    2012-01-01

    Full Text Available Hydropower accounts for about 16% of the world's electricity supply. It has been debated whether hydroelectric generation is merely an in-stream water user or whether it also consumes water. In this paper we provide scientific support for the argument that hydroelectric generation is in most cases a significant water consumer. The study assesses the blue water footprint of hydroelectricity – the water evaporated from manmade reservoirs to produce electric energy – for 35 selected sites. The aggregated blue water footprint of the selected hydropower plants is 90 Gm3 yr−1, which is equivalent to 10% of the blue water footprint of global crop production in the year 2000. The total blue water footprint of hydroelectric generation in the world must be considerably larger if one considers the fact that this study covers only 8% of the global installed hydroelectric capacity. Hydroelectric generation is thus a significant water consumer. The average water footprint of the selected hydropower plants is 68 m3 GJ−1. Great differences in water footprint among hydropower plants exist, due to differences in climate in the places where the plants are situated, but more importantly as a result of large differences in the area flooded per unit of installed hydroelectric capacity. We recommend that water footprint assessment is added as a component in evaluations of newly proposed hydropower plants as well as in the evaluation of existing hydroelectric dams, so that the consequences of the water footprint of hydroelectric generation on downstream environmental flows and other water users can be evaluated.

  1. 'Blue Whale Challenge': A Game or Crime?

    Science.gov (United States)

    Mukhra, Richa; Baryah, Neha; Krishan, Kewal; Kanchan, Tanuj

    2017-11-11

    A bewildering range of games are emerging every other day with newer elements of fun and entertainment to woo youngsters. Games are meant to reduce stress and enhance the cognitive development of children as well as adults. Teenagers are always curious to indulge in newer games; and e-gaming is one such platform providing an easy access and quicker means of entertainment. The particular game challenge which has taken the world by storm is the dangerous "Blue Whale Challenge" often involving vulnerable teenagers. The Blue Whale Challenge is neither an application nor internet based game but the users get a link through social media chat groups to enter this "deadly" challenge game. This probably is the only game where the participant has to end his/her life to complete the game. The innocent teenagers are being targeted based on their depressed psychology and are coercively isolated from their social milieux on the pretext of keeping the challenges confidential. To add to the woes, no option is offered to quit the challenge even if the contender is unable to complete the challenge. Blue Whale Challenge in its sheer form could be seen as an illegal, unethical and inhumane endeavor in our present society. The present communication discusses the severe effects of the game on teenagers, the ethical concerns involved and the preventive measures necessary to curb it.

  2. The assesment of flex blue implementation in Indonesia

    International Nuclear Information System (INIS)

    Sahala Maruli Lumbanraja

    2014-01-01

    Flex blue is a small power modular and light water cooled reactor. The reactor site is located at the bottom of the sea surface (off shore) and main control room on the ground. Hull that contains of the main reactor components is placed at a depth of 60-100 m in the bottom of the sea surface so that the safety and security system is quite high. NPP was developed by the DCNS-France to meet the electrical energy needs of the world. The purpose of this study was to study the pre-feasibility of Flex blue implementation in Indonesia based on technological factors, sea geographical conditions and regulatory. The methodology used is to study a variety of literature study on NPP Flex blue technology, geographic conditions, and regulatory systems in Indonesia. In this study, location of potential sites are on the east coast of the island of Sumatra, Java's northern coast, the coast of the Borneo island and surrounding coastal islands between the east of the Sumatra island, northern Java and Borneo, however in terms of regulation, this technology could not be implemented. (author)

  3. African Retentions in Blues and Jazz.

    Science.gov (United States)

    Meadows, Eddie S.

    1979-01-01

    The perseverance of African musical characteristics among American Blacks is an historic reality. African retentions have been recorded in Black music of the antebellum period. Various African scales and rhythms permeate Black American music today as evidenced in the retentions found in blues and jazz. (RLV)

  4. Investigating temporal patterns of a native bee community in a remnant North American bunchgrass prairie using blue vane traps.

    Science.gov (United States)

    Kimoto, Chiho; Debano, Sandra J; Thorp, Robbin W; Rao, Sujaya; Stephen, William P

    2012-01-01

    Native bees are important ecologically and economically because their role as pollinators fulfills a vital ecosystem service. Pollinators are declining due to various factors, including habitat degradation and destruction. Grasslands, an important habitat for native bees, are particularly vulnerable. One highly imperiled and understudied grassland type in the United States is the Pacific Northwest Bunchgrass Prairie. No studies have examined native bee communities in this prairie type. To fill this gap, the bee fauna of the Zumwalt Prairie, a large, relatively intact remnant of the Pacific Northwest Bunchgrass Prairie, was examined. Native bees were sampled during the summers of 2007 and 2008 in sixteen 40-ha study pastures on a plateau in northeastern Oregon, using a sampling method not previously used in grassland studies-blue vane traps. This grassland habitat contained an abundant and diverse community of native bees that experienced marked seasonal and inter-annual variation, which appears to be related to weather and plant phenology. Temporal variability evident over the entire study area was also reflected at the individual trap level, indicating a consistent response across the spatial scale of the study. These results demonstrate that temporal variability in bee communities can have important implications for long-term monitoring protocols. In addition, the blue vane trap method appears to be well-suited for studies of native bees in large expanses of grasslands or other open habitats, and may be a useful tool for monitoring native bee communities in these systems.

  5. High-power pure blue laser diodes

    Energy Technology Data Exchange (ETDEWEB)

    Ohta, M.; Ohizumi, Y.; Hoshina, Y.; Tanaka, T.; Yabuki, Y.; Goto, S.; Ikeda, M. [Development Center, Sony Shiroishi Semiconductor Inc., Miyagi (Japan); Funato, K. [Materials Laboratories, Sony Corporation, Kanagawa (Japan); Tomiya, S. [Materials Analysis Laboratory, Sony Corporation, Kanagawa (Japan)

    2007-06-15

    We successfully developed high-power and long-lived pure blue laser diodes (LDs) having an emission wavelength of 440-450 nm. The pure-blue LDs were grown by metalorganic chemical vapor deposition (MOCVD) on GaN substrates. The dislocation density was successfully reduced to {proportional_to}10{sup 6} cm{sup -2} by optimizing the MOCVD growth conditions and the active layer structure. The vertical layer structure was designed to have an absorption loss of 4.9 cm{sup -1} and an internal quantum efficiency of 91%. We also reduced the operating current density to 6 kA/cm{sup 2} under 750 mW continuous-wave operation at 35 C by optimizing the stripe width to 12 {mu}m and the cavity length to 2000 {mu}m. The half lifetimes in constant current mode are estimated to be longer than 10000 h. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  6. Habitat suitability—density relationship in an endangered woodland species: the case of the Blue Chaffinch (Fringilla polatzeki

    Directory of Open Access Journals (Sweden)

    Luis M. Carrascal

    2017-09-01

    Full Text Available Background Understanding constraints to the distribution of threatened species may help to ascertain whether there are other suitable sectors for reducing the risks associated with species that are recorded in only one protected locality, and to inform about the suitability of other areas for reintroduction or translocation programs. Methods We studied the Gran Canaria blue chaffinch (Fringilla polatzeki, a habitat specialist endemic of the Canary Islands restricted to the pine forest of Inagua, the only area where the species has been naturally present as a regular breeder in the last 25 years. A suitability distribution model using occurrences with demographic relevance (i.e., nest locations of successful breeding attempts analysed using boosted classification trees was built considering orographic, climatic and habitat structure predictors. By means of a standardized survey program we monitored the yearly abundance of the species in 100 sectors since the declaration of Inagua as a Strict Nature Reserve in 1994. Results The variables with the highest relative importance in blue chaffinch habitat preferences were pine height, tree cover, altitude, and rainfall during the driest trimester (July–September. The observed local abundance of the blue chaffinch in Inagua (survey data was significantly correlated with habitat suitability derived from modelling the location of successful nesting attempts (using linear and quantile regressions. The outcomes of the habitat suitability model were used to quantify the suitability of other natural, historic, pine forests of Gran Canaria. Tamadaba is the forest with most suitable woodland patches for the species. We estimated a population size of 195–430 blue chaffinches in Inagua since 2011 (95% CI, the smallest population size of a woodland passerine in the Western Palearctic. Discussion Habitat suitability obtained from modelling the location of successful breeding attempts is a good surrogate of the

  7. Fecal steroid hormones reveal reproductive state in female blue whales sampled in the Gulf of California, Mexico.

    Science.gov (United States)

    Valenzuela-Molina, Marcia; Atkinson, Shannon; Mashburn, Kendall; Gendron, Diane; Brownell, Robert L

    2018-05-15

    Steroid hormone assessment using non-invasive sample collection techniques can reveal the reproductive status of aquatic mammals and the physiological mechanisms by which they respond to changes in their environment. A portion of the eastern North Pacific blue whale (Balaenoptera musculus) population that seasonally visits the Gulf of California, Mexico has been monitored using photo-identified individuals for over 30 years. The whales use the area in winter-early spring for nursing their calves and feeding and it therefore is well suited for fecal sample collection. Using radioimmunoassays in 25 fecal samples collected between 2009 and 2012 to determine reproductive state and stress, we validated three steroid hormones (progesterone, corticosterone and cortisol) in adult female blue whales. Females that were categorized as pregnant had higher mean fecal progesterone metabolite concentrations (1292.6 ± 415.6 ng·g -1 ) than resting and lactating females (14.0 ± 3.7 ng·g -1 ; 23.0 ± 5.4 ng·g -1 , respectively). Females classified as pregnant also had higher concentrations of corticosterone metabolites (37.5 ± 9.9 ng·g -1 ) than resting and lactating females (17.4 ± 2.0 ng·g -1 ; 16.8 ± 2.8 ng·g -1 , respectively). In contrast, cortisol metabolite concentrations showed high variability between groups and no significant relationship to reproductive state. We successfully determined preliminary baseline parameters of key steroid hormones by reproductive state in adult female blue whales. The presence of pregnant or with luteal activity and known lactating females confirms that the Gulf of California is an important winter-spring area for the reproductive phase of these blue whales. The baseline corticosterone levels we are developing will be useful for assessing the impact of the increasing coastal development and whale-watching activities on the whales in the Gulf of California. Copyright © 2018 Elsevier Inc. All

  8. Marennine, Promising Blue Pigments from a Widespread Haslea Diatom Species Complex

    Directory of Open Access Journals (Sweden)

    Romain Gastineau

    2014-05-01

    Full Text Available In diatoms, the main photosynthetic pigments are chlorophylls a and c, fucoxanthin, diadinoxanthin and diatoxanthin. The marine pennate diatom Haslea ostrearia has long been known for producing, in addition to these generic pigments, a water-soluble blue pigment, marennine. This pigment, responsible for the greening of oysters in western France, presents different biological activities: allelopathic, antioxidant, antibacterial, antiviral, and growth-inhibiting. A method to extract and purify marennine has been developed, but its chemical structure could hitherto not be resolved. For decades, H. ostrearia was the only organism known to produce marennine, and can be found worldwide. Our knowledge about H. ostrearia-like diatom biodiversity has recently been extended with the discovery of several new species of blue diatoms, the recently described H. karadagensis, H. silbo sp. inedit. and H. provincialis sp. inedit. These blue diatoms produce different marennine-like pigments, which belong to the same chemical family and present similar biological activities. Aside from being a potential source of natural blue pigments, H. ostrearia-like diatoms thus present a commercial potential for aquaculture, cosmetics, food and health industries.

  9. Photochemical transformation of silver nanoparticles by combining blue and green irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Cardoso-Avila, P. E.; Pichardo-Molina, J. L., E-mail: jpichardo@cio.mx [Centro de Investigaciones en Optica A.C (Mexico); Krishna, C. Murali [Advanced Center for Treatment, Research and Education in Cancer (ACTREC), Tata Memorial Center (TMC) (India); Castro-Beltran, R. [Centro de Investigaciones en Optica A.C (Mexico)

    2015-03-15

    Spherical silver nanoparticles (diameter 3 nm) were transformed by means of photochemical synthesis using superluminescent LEDs. Flat rounded (21 nm) and decahedral nanoparticles (78 nm) were, respectively, obtained when the colloid was exposed to green and blue radiation. Furthermore, by changing from blue to green radiation at different exposure times, various morphologies and sizes were obtained. Exposure times shorter than 30 min of blue radiation followed by green radiation resulted on different morphologies such as twine rounded (42 nm), flat elongated (peanuts, 17 nm), and flat rounded nanoparticles (11 and 24 nm). Times longer than 45 min produced decahedral nanoparticles with corners ranging from rounded to sharp (size 71–78 nm). Additionally, these results showed that by controlling morphologies and sizes through the combination of blue and green light at different exposure times, it was possible to tune the plasmon band from 511 to 594 nm. Moreover, controlling the morphology of nanoparticles is of prime importance in order to exploit their properties as part of novel emerging technologies.

  10. A fluorescent stilbenoid dendrimer for solution-processed blue light emitting diodes

    Science.gov (United States)

    Coya, C.; Álvarez, A. L.; Ramos, M.; de Andrés, A.; Zaldo, C.; Gómez, R.; Segura, J. L.; Seoane, C.

    2008-04-01

    We report a solution processed blue stilbenoid dendrimer based on a 1, 3, 5 - benzene core and endowed with a periphery of electron donating and solubilizing alkoxy chains. Raman analysis it is revealed as a helpful tool to investigate changes from the pristine material to the material in the OLED structure, explaining the differences between the dendrimer single layer thin film photoluminescence (PL) and the electroluminescence (EL) dendrimer active layer emission in the device. We report a blue EL emission (439 nm) and a very promising effective mobility value of 2.55 × 10 -5 cm2/(V•s) suggesting good transport properties for non doped blue OLEDs that use air stable Al as the cathode.

  11. Tm3+ activated lanthanum phosphate: a blue PDP phosphor

    International Nuclear Information System (INIS)

    Rao, R.P.

    2005-01-01

    Plasma display panels (PDPs) are gaining attention due to their high performance and scalability as a medium for large format TVs. The performance and life of a PDP strongly depends upon the nature of phosphors. Currently, Eu 2+ activated barium magnesium aluminate (BAM) is being used as a blue component. Because of its low life, efforts are being made to explore new blue emitting phosphors. One of the alternatives to BAM is Tm 3+ activated lanthanum phosphate (LPTM) phosphor. LPTM phosphor samples are prepared by a solid-state as well as sol-gel process in presence of flux. The phosphor of the present investigation, having uniform and spherical shape particles in the range of 0.1-2 μm, is appropriate for thin phosphor screens required for PDP applications. It exhibits a narrow band emission in the blue region, peaking at 452 nm and also a number of narrow bands in the UV region when excited by 147 and 173 nm radiation from a xenon gas mixture. Various possible transitions responsible for UV and visible emission from Tm 3+ ion are presented. These phosphors also exhibit good color saturation and better stability when excited with VUV radiation. To achieve higher brightness, they are blended with other UV excited blue emitting phosphors such as BAM. Results related to morphology, excitation, after glow decay, emission and degradation of these phosphors in the powder form as well as in plasma display panels are presented and discussed

  12. Adsorption of a textile dye "Indanthrene Blue RS (C.I. Vat Blue 4)" from aqueous solutions onto smectite-rich clayey rock.

    Science.gov (United States)

    Chaari, Islem; Feki, Mongi; Medhioub, Mounir; Bouzid, Jalel; Fakhfakh, Emna; Jamoussi, Fakher

    2009-12-30

    The adsorption of a textile dye, namely, Indanthrene Blue RS (C.I. Vat Blue 4) onto smectite-rich clayey rock (AYD) and its sulphuric acid-activated products (AYDS) in aqueous solution was studied in a batch system with respect to contact time, pH, and temperature. The adsorbents employed were characterized by X-ray diffraction, infrared spectroscopy and specific surface area, cation exchange capacity and point of zero charge were also estimated. The effect of contact time on dye adsorption showed that the equilibrium was reached after a contact time of 40 min for the both adsorbents. The optimum pH for dye retention was found 6.0 for AYDS and 7.3 for AYD. The equilibrium adsorption data were analysed using the Langmuir and Freundlich isotherms. The adsorption capacities (Q(m)) for AYD and AYDS were found 13.92 mg/g and 17.85 mg/g, respectively. The effect of temperature on the adsorption was also investigated; adsorption of Indanthrene Blue RS is an endothermic process. This study demonstrates that all the considered adsorbents can be used as an alternative emerging technology for water treatment.

  13. The Return of the Blue Butterfly

    Science.gov (United States)

    Santos, Anabela

    2014-05-01

    The Return of the Blue Butterfly The English writer Charles Dickens once wrote: "I only ask to be free. The butterflies are free". But are they really? The work that I performed with a group of students from 8th grade, had a starting point of climate change and the implications it has on ecosystems. Joining the passion I have for butterflies, I realized that they are also in danger of extinction due to these climatic effects. Thus, it was easy to seduce my students wanting to know more. Luckily I found Dr. Paula Seixas Arnaldo, a researcher at the University of Trás-os-Montes and Alto Douro, who has worked on butterflies and precisely investigated this issue. Portugal is the southern limit of butterfly-blue (Phengaris alcon), and has been many years in the red book of endangered species. Butterfly-blue is very demanding of their habitat, and disappears very easily if ideal conditions are not satisfied. Increased fragmentation of landscapes and degradation of suitable habitats, are considered the greatest challenges of the conservation of Phengaris butterfly in Portugal. In recent decades, climate change has also changed butterfly-blue spatial distribution with a movement of the species northward to colder locations, and dispersion in latitude. Butterflies of Europe must escape to the North because of the heat. Dr. Paula Seixas Arnaldo and her research team began a project, completed in December 2013, wanted to preserve and restore priority habitats recognized by the European Union to help species in danger of disappearing with increasing temperature. The blue butterfly is extremely important because it is a key indicator of the quality of these habitats. In the field, the butterflies are monitored to collect all possible data in order to identify the key species. Butterflies start flying in early July and cease in late August. Mating takes about an hour and occurs in the first days of life. The gentian-peat (Gentiana pneumonanthe) serves as the host plant for

  14. Blue Light Emitting Diodes for Optical Stimulation of Quartz in Retrospective Dosimetry and Dating (invited paper)

    International Nuclear Information System (INIS)

    Botter-Jensen, L.; Duller, G.A.T.; Murray, A.S.; Banerjee, D.

    1999-01-01

    Recently developed blue light emitting diodes (LEDs) for the optical stimulation of quartz for use in routine optically stimulated luminescence (OSL) dating and retrospective dosimetry have been tested. For similar power densities, it was found that the higher energy light provided by the blue LEDs (470 nm) gives order of magnitude greater rate of stimulation in quartz than that from conventional blue-green light filtered from a halogen lamp. A practical blue LED OSL configuration is described. From comparisons of OSL decay curves produced by green and blue light sources, and by examination of the dependence of the blue LED OSL on preheat temperature, it is deduced that there is no evidence that the blue LEDs stimulate deep traps in a different manner from broadband filtered light. It is concluded that blue LEDs offer a practical alternative to existing stimulation sources. They have the significant advantages that the life-time is indefinite, and the output can be controlled electronically; this allows the power to be readily controlled by software. Unlike a filtered light source, there are no electromechanical parts, and the switch on/off times are about 10 times faster than a shutter. Finally, preliminary results from ramping the blue light power output with time are demonstrated. It is shown that this technique enables the separation of OSL components with differing stimulation rates. (author)

  15. Photo Inactivation of Streptococcus mutans Biofilm by Violet-Blue light.

    Science.gov (United States)

    Gomez, Grace F; Huang, Ruijie; MacPherson, Meoghan; Ferreira Zandona, Andrea G; Gregory, Richard L

    2016-09-01

    Among various preventive approaches, non-invasive phototherapy/photodynamic therapy is one of the methods used to control oral biofilm. Studies indicate that light at specific wavelengths has a potent antibacterial effect. The objective of this study was to determine the effectiveness of violet-blue light at 380-440 nm to inhibit biofilm formation of Streptococcus mutans or kill S. mutans. S. mutans UA159 biofilm cells were grown for 12-16 h in 96-well flat-bottom microtiter plates using tryptic soy broth (TSB) or TSB with 1 % sucrose (TSBS). Biofilm was irradiated with violet-blue light for 5 min. After exposure, plates were re-incubated at 37 °C for either 2 or 6 h to allow the bacteria to recover. A crystal violet biofilm assay was used to determine relative densities of the biofilm cells grown in TSB, but not in TSBS, exposed to violet-blue light. The results indicated a statistically significant (P mutans growth and reduce the formation of S. mutans biofilm. This in vitro study demonstrated that violet-blue light has the capacity to inhibit S. mutans biofilm formation. Potential clinical applications of light therapy in the future remain bright in preventing the development and progression of dental caries.

  16. Blue light inhibits the growth of B16 melanoma cells

    International Nuclear Information System (INIS)

    Ohara, Masayuki; Katoh, Osamu; Watanabe, Hiromitsu

    2002-01-01

    Although a number of studies have been carried out to examine the biological effects of radiation and ultraviolet radiation (UV), little is known concerning the effects of visible light. In the present study, exposure of B16 melanoma cells to blue light (wavelength 470 nm, irradiance 5.7 mW/cm 2 ) from a light-emitting diode (LED) inhibited cell growth in proportion to the period of exposure, with no increase observed in the number of dead cells. The number of B16 melanoma colonies that formed after exposure to blue light for 20 min was only slightly less than that in non-exposed controls, but the colony size as assessed by the area covered by colonies and cell counts per colony were markedly decreased. The percentages of G0/G1 and G2/M phase cells were markedly increased, with a reduction in S phase cells as determined by flow cytometry after exposure to blue light. Furthermore, analysis of the incorporation of 5-bromo-2'-deoxyuridine (BrdU) into DNA also showed a reduction in the percentage of S phase cells after exposure. These results indicate that blue light exerts cytostatic effects, but not a cytocidal action, on B16 melanoma cells. (author)

  17. Blue light inhibits the growth of B16 melanoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Ohara, Masayuki; Katoh, Osamu; Watanabe, Hiromitsu [Hiroshima Univ. (Japan). Research Inst. for Radiation Biology and Medicine; Kawashima, Yuzo [Otsuka Pharmaceutical Factory, Inc., Naruto, Tokushima (Japan)

    2002-05-01

    Although a number of studies have been carried out to examine the biological effects of radiation and ultraviolet radiation (UV), little is known concerning the effects of visible light. In the present study, exposure of B16 melanoma cells to blue light (wavelength 470 nm, irradiance 5.7 mW/cm{sup 2}) from a light-emitting diode (LED) inhibited cell growth in proportion to the period of exposure, with no increase observed in the number of dead cells. The number of B16 melanoma colonies that formed after exposure to blue light for 20 min was only slightly less than that in non-exposed controls, but the colony size as assessed by the area covered by colonies and cell counts per colony were markedly decreased. The percentages of G0/G1 and G2/M phase cells were markedly increased, with a reduction in S phase cells as determined by flow cytometry after exposure to blue light. Furthermore, analysis of the incorporation of 5-bromo-2'-deoxyuridine (BrdU) into DNA also showed a reduction in the percentage of S phase cells after exposure. These results indicate that blue light exerts cytostatic effects, but not a cytocidal action, on B16 melanoma cells. (author)

  18. Locating the origins of blue and white porcelains using EDXRF

    International Nuclear Information System (INIS)

    Yu, K.N.; Miao, J.M.

    1997-01-01

    Among the main sites of production of ancient Chinese blue and white porcelains can be included Jingdezhen in Jiangxi Province, the Yuxi and Jianshui Kilns of Yunnan Province and the Pinghe Kiln of Fujian Province. The current work focuses on an elemental characterization of ancient porcelains according to the location of manufacture, also incorporating a similar study of the blue and white porcelains of the Qing dynasty from Wun Yiu in Hong Kong, and modern blue and white porcelains from Germany, Japan and Thailand. Non-destructive analysis of samples of porcelain using energy dispersive X-ray fluorescence (EDXRF) has yielded results in terms of 13 chemical elements, namely, Ti, Mn, Fe, Co, Ni, Cu, Zn, Ga, Pb, Rb, Sr, Y and Zr. Principal component analysis has been performed on the data, allowing representation of the first, second and third principal components of the data in 3 D scatter plots; the results reveal data clusterings which correlate to a high degree with the known sites of origin. The conclusion is that the present method is capable of determining differences in elemental concentrations of blue and white porcelains, and that these differences can be used to locate the originating site of manufacture. (Author)

  19. Dynamics of InGaN tandem blue-violet semiconductor lasers

    International Nuclear Information System (INIS)

    Antohi, I.; Rusu, S.S.; Tronciu, V.Z.

    2013-01-01

    Full text: Blue-violet semiconductor lasers have received much attention because of their promise for high-density optical storage applications. In particular, blue-violet laser diodes operating at 400 nm are required for BD- systems and for use in medicine, biology, color printers and monitors, etc, In recent years, numerous fabrication methods have been proposed and developed for blue lasers with CW and self-pulsating operations and the lifetime of such lasers has been increased to over 15000 h. Recently, we have reported self-pulsation and excitable behaviour for an InGaN laser with a p-type saturable absorber, and SP in the frequency range from 1.6 to 2.9 GHz has been achieved with such lasers. In this paper, we present an investigation of the dynamics of tandem 400 nm blue-violet lasers with setup presented in Fig.1a. A particular feature of the devices is the connection of the contacts of the SA, to reduce the carrier lifetime in the SA with the intention of producing self-pulsation and excitability. We examine the laser dynamics in terms of bifurcation diagrams. A typical calculation of bifurcation for the periodic solution is shown in Fig. 1b. This figure shows the dependence of the peak of the photon number on the injected.

  20. Locating the origins of blue and white porcelains using EDXRF

    Energy Technology Data Exchange (ETDEWEB)

    Yu, K.N. [City Univ., Hong Kong (Hong Kong). Dept. of Physics and Materials Science; Miao, J.M. [Palace Museum, Beijing (China). Dept. of Science and Technology

    1997-07-30

    Among the main sites of production of ancient Chinese blue and white porcelains can be included Jingdezhen in Jiangxi Province, the Yuxi and Jianshui Kilns of Yunnan Province and the Pinghe Kiln of Fujian Province. The current work focuses on an elemental characterization of ancient porcelains according to the location of manufacture, also incorporating a similar study of the blue and white porcelains of the Qing dynasty from Wun Yiu in Hong Kong, and modern blue and white porcelains from Germany, Japan and Thailand. Non-destructive analysis of samples of porcelain using energy dispersive X-ray fluorescence (EDXRF) has yielded results in terms of 13 chemical elements, namely, Ti, Mn, Fe, Co, Ni, Cu, Zn, Ga, Pb, Rb, Sr, Y and Zr. Principal component analysis has been performed on the data, allowing representation of the first, second and third principal components of the data in 3 D scatter plots; the results reveal data clusterings which correlate to a high degree with the known sites of origin. The conclusion is that the present method is capable of determining differences in elemental concentrations of blue and white porcelains, and that these differences can be used to locate the originating site of manufacture. (Author).