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Sample records for cage bulk negative-index

  1. The split cube in a cage: bulk negative-index material for infrared applications

    DEFF Research Database (Denmark)

    Andryieuski, Andrei; Menzel, C.; Rockstuhl, C.

    2009-01-01

    We propose the split cube in a cage (SCiC) design for application in producing a bulk metamaterial. Applying realistic material data for thin silver films, we observe an immediate convergence of the effective parameters obtained with a number of layers towards the bulk properties. Results are obt...

  2. Bulk isotropic negative-index material design for infrared

    DEFF Research Database (Denmark)

    Andryieuski, Andrei; Malureanu, Radu; Lavrinenko, Andrei

    Responding to the strong call for isotropic bulk negative index material we propose a Split Cube in Car-cass design. It shows negative refractive index -1.5, figure-of-merit 2 and transmittivity 30% for one layer at the telecommunication wavelength 1.6 μm. Effective parameters converge fast with ...

  3. Negative Index Materials and Plasmonic Antennas Based Nanocouplers

    DEFF Research Database (Denmark)

    Andryieuski, Andrei

    an optical fiber and future optical integrated circuit. Multiple nanocoupler possibilities are analyzed. Two realizations are investigated: negative index metamaterial and plasmonic nanoantenna based. The cubic symmetric negative index metamaterial Split cube in Cage and Split cube in Carcass designs...... for the telecom frequencies are proposed. It is shown that despite the exceptional bulkness (effective properties do not depend on the number of layers) and cubic symmetry the abovementioned designs exhibit strong spatial dispersion in the frequency range of interest. That prevents treating them as an isotropic...... negative index material. The wave propagation retrieval method for metamaterials with linear and circular eigenpolarizations and the field averaging of the restored Bloch mode method are proposed for metamaterials effective properties characterization. The methods are based on observation of the wave...

  4. Energy flow in negative index materials

    Institute of Scientific and Technical Information of China (English)

    Lorenzo Bolla; Michele Midrio; Carlo G. Someda

    2004-01-01

    From Maxwell's equations, we compute the speed and the direction of propagation of active power refractedfrom air into a negative index material. We prove, both analytically and numerically that the power mayrefract positively even if phase fronts refract negatively. Considerations on the usage of ray optics inproblems involving negative index materials are drawn.

  5. Towards negative index self-assembled metamaterials

    CERN Document Server

    Fruhnert, Martin; Lederer, Falk; Rockstuhl, Carsten

    2016-01-01

    We investigate the magnetic response of meta-atoms that can be fabricated by a bottom-up technique. Usually such meta-atoms consist of a dielectric core surrounded by a large number of solid metallic nanoparticles. In contrast to those meta-atoms considered thus far, we study here for the first time hollow metallic nanoparticles (shells). In doing so we solve one of the most pertinent problems of current self-assembled metamaterials, namely implementing meta-atoms with sufficiently large resonance strength and small absorption. Both conditions have to be met for deep sub-wavelength meta-atoms to obtain effectively homogeneous metamaterials which may be meaningfully described by negative material parameters. Eventually we show that by using these findings self-assembled negative index materials come in reach.

  6. Optical properties of multilayer optics including negative index materials

    OpenAIRE

    Lequime, Michel; Gralak, Boris; guenneau, sebastien; Zerrad, Myriam; Amra, Claude

    2013-01-01

    Negative indices are revisited through the thin-film admittance formalism. Effective indices and phase delay associated with wave propagation through negative index layers are carefully defined and computational rules easily implementable in standard thin-film software are derived from this approach. This admittance formalism is then used to recover the main features of the perfect lens and to highlight the benefit of such negative index materials to improve the performances of quarter-wavele...

  7. Optical properties of multilayer optics including negative index materials

    CERN Document Server

    Lequime, Michel; Guenneau, Sebastien; Zerrad, Myriam; Amra, Claude

    2013-01-01

    Negative indices are revisited through the thin-film admittance formalism. Effective indices and phase delay associated with wave propagation through negative index layers are carefully defined and computational rules easily implementable in standard thin-film software are derived from this approach. This admittance formalism is then used to recover the main features of the perfect lens and to highlight the benefit of such negative index materials to improve the performances of quarter-wavelength Bragg mirrors and Fabry-Perot band-pass filters.

  8. Radiation Pressure and Photon Momentum in Negative-Index Media

    CERN Document Server

    Mansuripur, Masud

    2013-01-01

    Radiation pressure and photon momentum in negative-index media are no different than their counterparts in ordinary (positive-index) materials. This is because the parameters responsible for these properties are the admittance, sqrt(epsilon/mu), and the group refractive index n_g of the material (both positive entities), and not the phase refractive index, n=sqrt(epsilon*mu), which is negative in negative-index media. One approach to investigating the exchange of momentum between electromagnetic waves and material media is via the Doppler shift phenomenon. In this paper we use the Doppler shift to arrive at an expression for the radiation pressure on a mirror submerged in a negative-index medium. In preparation for the analysis, we investigate the phenomenon of Doppler shift in various settings, and show the conditions under which a so-called "inverse" Doppler shift could occur. We also argue that a recent observation of the inverse Doppler shift upon reflection from a negative-index medium cannot be correct,...

  9. Negative-index metamaterials: looking into the unit cell

    NARCIS (Netherlands)

    Burresi, M.; Diessel, D.; van Oosten, D.; Linden, Stefan; Wegener, M.; Kuipers, L.

    2010-01-01

    With their potential for spectacular applications, like superlensing and cloaking, metamaterials are a powerful class of nanostructured materials. All these applications rely on the metamaterials acting as a homogeneous material. We investigate a negative index metamaterial with a phase-sensitive ne

  10. On the Fourier coefficients of negative index meromorphic Jacobi forms

    CERN Document Server

    Bringmann, Kathrin; Zwegers, Sander

    2015-01-01

    In this paper, we consider the Fourier coefficients of meromorphic Jacobi forms of negative index. This extends recent work of Creutzig and the first two authors for the special case of Kac-Wakimoto characters which occur naturally in Lie theory, and yields, as easy corollaries, many important PDEs arising in combinatorics such as the famous rank-crank PDE of Atkin and Garvan. Moreover, we discuss the relation of our results to partial theta functions and quantum modular forms as introducted by Zagier, which together with previous work on positive index meromorphic Jacobi forms illuminates the general structure of the Fourier coefficients of meromorphic Jacobi forms.

  11. Merging Nonlinear Optics and Negative-Index Metamaterials

    CERN Document Server

    Popov, Alexander K

    2011-01-01

    The extraordinary properties of nonlinear optical propagation processes in double-domain positive/negative index metamaterials are reviewed. These processes include second harmonic generation, three- and four-wave frequency mixing, and optical parametric amplification. Striking contrasts with the properties of the counterparts in ordinary materials are shown. We also discuss the possibilities for compensating strong losses inherent to plasmonic metamaterials, which present a major obstacle in numerous exciting applications, and the possibilities for creation of unique ultracompact photonic devices such as data processing chips and nonlinear-optical sensors. Finally, we propose similar extraordinary three-wave mixing processes in crystals based on optical phonons with negative dispersion.

  12. Electromagnetic field energy density in homogeneous negative index materials.

    Science.gov (United States)

    Shivanand; Webb, Kevin J

    2012-05-07

    An exact separation of both electric and magnetic energies into stored and lost energies is shown to be possible in the special case when the wave impedance is independent of frequency. A general expression for the electromagnetic energy density in such a dispersive medium having a negative refractive index is shown to be accurate in comparison with numerical results. Using an example metamaterial response that provides a negative refractive index, it is shown that negative time-averaged stored energy can occur. The physical meaning of this negative energy is explained as the energy temporarily borrowed by the field from the material. This observation for negative index materials is of interest when approaching properties for a perfect lens. In the broader context, the observation of negative stored energy is of consequence in the study of dispersive materials.

  13. Optical Properties of Synthetic Cannabinoids with Negative Indexes

    CERN Document Server

    Shen, Yao

    2016-01-01

    Some kinds of psychoactive drugs have the structures which are called split-ring resonators (SRRs). SRRs might result in negative permittivity and permeability simultaneously in electromagnetic field. Simultaneous negative indexes can lead to the famous phenomenon of negative refraction. This optical property makes it possible to distinguish synthetic cannabinoids from other abusive psychoactive drugs in the UV-vis region. This optical method is non-damaged and superior in forensic science. In this paper, we use tight-binding model calculating the permittivity and permeability of the main ingredients of synthetic cannabinoids. At the same time, we give two more results of zolpidem and caffeine. Further we discuss the negative refraction of the category of zepam qualitatively.

  14. Sub-picosecond optical switching with a negative index metamaterial

    Energy Technology Data Exchange (ETDEWEB)

    Dani, Keshav M [Los Alamos National Laboratory; Upadhya, Prashant C [Los Alamos National Laboratory; Zahyum, Ku [CHTM-UNM

    2009-01-01

    Development of all-optical signal processing, eliminating the performance and cost penalties of optical-electrical-optical conversion, is important for continu,ing advances in Terabits/sec (Tb/s) communications.' Optical nonlinearities are generally weak, traditionally requiring long-path, large-area devicesl,2 or very high-Q, narrow-band resonator structures.3 Optical metamaterials offer unique capabilities for optical-optical interactions. Here we report 600 femtosecond (fs) all-optical modulation using a fIShnet (2D-perforated metallamorphous-Si (a-Si)/metal film stack) negative-index meta material with a structurally tunable broad-band response near 1.2 {micro}m. Over 20% modulation (experimentally limited) is achieved in a path length of only 116 nm by photo-excitation of carriers in the a-Si layer. This has the potential for Tb/s aU-optical communication and will lead to other novel, compact, tunable sub-picosecond (ps) photonic devices.

  15. Low-loss negative index metamaterials for X, Ku, and K microwave bands

    Directory of Open Access Journals (Sweden)

    David A. Lee

    2015-04-01

    Full Text Available Low-loss, negative-index of refraction metamaterials were designed and tested for X, Ku, and K microwave frequency bands. An S-shaped, split-ring resonator was used as a unit cell to design homogeneous slabs of negative-index metamaterials. Then, the slabs of metamaterials were cut unto prisms to measure experimentally the negative index of refraction of a plane electromagnetic wave. Theoretical simulations using High-Frequency Structural Simulator, a finite element equation solver, were in good agreement with experimental measurements. The negative index of refraction was retrieved from the angle- and frequency-dependence of the transmitted intensity of the microwave beam through the metamaterial prism and compared well to simulations; in addition, near-field electromagnetic intensity mapping was conducted with an infrared camera, and there was also a good match with the simulations for expected frequency ranges for the negative index of refraction.

  16. Relationship between the Kramers-Kronig relations and negative index of refraction

    CERN Document Server

    Hickey, Mark C; Kussow, Adil-Gerai

    2010-01-01

    The condition for a negative index of refraction with respect to the vacuum index is established in terms of permittivity and permeability susceptibilities. It is found that the imposition of analyticity to satisfy the Kramers-Kronig relations is a sufficiently general criterion for a physical negative index. The satisfaction of the Kramers-Kronig relations is a manifestation of the principle of causality and the predicted frequency region of negative index agrees with the Depine-Lakhtakia condition for the phase velocity being anti-directed to the Poynting vector, although the conditions presented here do not assume {\\it a priori} a negative solution branch for n.

  17. Plasmon-Enhanced Photonic Crystal Negative Index Materials for Superlensing Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Negative index materials (NIMs) offer tremendous potential for the formation of highly compact as well as large-area deployable thin-film optical components. Omega...

  18. Relations between Multi-Poly-Bernoulli numbers and Poly-Bernoulli numbers of negative index

    OpenAIRE

    Komaki, Hiroyuki

    2015-01-01

    Poly-Bernoulli numbers $B_n^{(k)}\\in\\mathbb{Q}$\\,($n \\geq 0$,\\,$k \\in \\mathbb{Z}$) are defined by Kaneko in 1997. Multi-Poly-Bernoulli numbers\\,$B_n^{(k_1,k_2,\\ldots, k_r)}$, defined by using multiple polylogarithms, are generations of Kaneko's Poly-Bernoulli numbers\\,$B_n^{(k)}$. We researched relations between Multi-Poly-Bernoulli numbers and Poly-Bernoulli numbers of negative index in particular. In section 2, we introduce a identity for Multi-Poly-Bernoulli numbers of negative index which...

  19. The use of a negative index planoconcave lens array for wide-viewing angle integral imaging.

    Science.gov (United States)

    Kim, Hwi; Hahn, Joonku; Lee, Byoungho

    2008-12-22

    Wide-viewing angle integral imaging by means of a negative refractive index planoconcave lens array is theoretically investigated. The optical properties of a negative refractive index lens are analyzed from the point of view of integral imaging. The effective focal length of a positive index planoconvex lens and a negative index planoconcave lens with the same surface spherical curvature R are approximated as fP,eff = 2R and fN,eff = 0.4 R, respectively. This short effective focal length of the negative index lens is advantageous for extending the viewing angle of the integral imaging. In addition, some other optical properties of a negative index lens are analyzed and compared for a positive index lens. Three-dimensional ray-tracing observation simulations of integral imaging systems with a negative index lens array and a positive index lens array are then performed, in a comparative study of the wide- ewing angle mode for integral imaging. A three-dimensional ray-tracing simulator for an integral imaging system is then developed. Some interesting issues that appear in the wide-viewing mode of integral imaging are discussed. The negative refractive index planoconcave lens was found to give a wider viewing angle of -60(deg.) approximately +60(deg.) and reduces aberration with only a single spherical planoconcave lens.

  20. (Department of Science)On certain properties of poly-Bernoulli numbers with negative index

    OpenAIRE

    坂田, 実加; 大野, 泰生

    2013-01-01

    Poly-Bernoulli numbers were introduced and studied by M. Kaneko as a generalization of classical Bernoulli numbers. In this article, for any prime number ρ, certain congruence properties of poly-Bernoulli numbers with negative index modulo ρare given.

  1. Negative-index gratings formed by femtosecond laser overexposure and thermal regeneration.

    Science.gov (United States)

    He, Jun; Wang, Yiping; Liao, Changrui; Wang, Chao; Liu, Shen; Yang, Kaiming; Wang, Ying; Yuan, Xiaocong; Wang, Guo Ping; Zhang, Wenjing

    2016-03-16

    We demonstrate a method for the preparation of negative-index fibre Bragg gratings (FBGs) using 800 nm femtosecond laser overexposure and thermal regeneration. A positive-index type I-IR FBG was first inscribed in H2-free single-mode fibre using a femtosecond laser directed through a phase mask, and then a highly polarization dependant phase-shifted FBG (P-PSFBG) was fabricated from the type I-IR FBG by overexposure to the femtosecond laser. Subsequently, the P-PSFBG was thermally annealed at 800 °C for 12 hours. Grating regeneration was observed during thermal annealing, and a negative-index FBG was finally obtained with a high reflectivity of 99.22%, an ultra-low insertion loss of 0.08 dB, a blueshift of 0.83 nm in the Bragg wavelength, and an operating temperature of up to 1000 °C for more than 10 hours. Further annealing tests showed that the thermal stability of the negative-index FBG was lower than that of a type II-IR FBG, but much higher than that of a type I-IR FBG. Moreover, the formation of such a negative-index grating may result from thermally regenerated type IIA photosensitivity.

  2. Enlargement of zero averaged refractive index gaps in the photonic heterostructures containing negative-index materials.

    Science.gov (United States)

    Xiang, Yuanjiang; Dai, Xiaoyu; Wen, Shuangchun; Fan, Dianyuan

    2007-11-01

    We show that the frequency range of the zero averaged refractive index gap in a photonic heterostructure containing negative-index materials can be enlarged owing to the property that its lower and upper frequency edges depend on the thickness ratio of the positive- and negative-index materials. Compared to the zero averaged refractive index gap of a single photonic crystal, the frequency range of the zero averaged refractive index gaps in a photonic heterostructure can be notably enlarged. Moreover, it is shown that the band edge of the zero averaged refractive index gap is determined not only by the TM polarization but also by the TE polarization, which is obviously different from the omnidirectional band gaps in conventional photonic crystals, whose bandwidth is determined by the TM polarization.

  3. Creating double negative index materials using the Babinet principle with one metasurface

    Science.gov (United States)

    Zhang, Lei; Koschny, Thomas; Soukoulis, C. M.

    2013-01-01

    Metamaterials are patterned metallic structures which permit access to a novel electromagnetic response, negative index of refraction, impossible to achieve with naturally occurring materials. Using the Babinet principle, the complementary split ring resonator (SRR) is etched in a metallic plate to provide negative ɛ, with perpendicular direction. Here we propose a new design, etched in a metallic plate to provide negative magnetic permeability μ, with perpendicular direction. The combined electromagnetic response of this planar metamaterial, where the negative μ comes from the aperture and the negative ɛ from the remainder of the continuous metallic plate, allows achievement of a double negative index metamaterial (NIM) with only one metasurface and strong transmission. These designs can be used to fabricate NIMs at microwave and optical wavelengths and three-dimensional metamaterials.

  4. Observation of the inverse Doppler effect in negative-index materials at optical frequencies

    Science.gov (United States)

    Chen, Jiabi; Wang, Yan; Jia, Baohua; Geng, Tao; Li, Xiangping; Feng, Lie; Qian, Wei; Liang, Bingming; Zhang, Xuanxiong; Gu, Min; Zhuang, Songlin

    2011-04-01

    The Doppler effect is a fundamental frequency shift phenomenon that occurs whenever a wave source and an observer are moving with respect to one another. It has well-established applications in astrophotonics, biological diagnostics, weather and aircraft radar systems, velocimetry and vibrometry. The counterintuitive inverse Doppler effect was theoretically predicted in 1968 by Veselago in negative-index materials. However, because of the tremendous challenges of frequency shift measurements inside such materials, most investigations of the inverse Doppler effect have been limited to theoretical predictions and numerical simulations. Indirect experimental measurements have been conducted only in nonlinear transmission lines at ~1-2 GHz (ref. 8) and in acoustic media at 1-3 kHz (ref. 9). Here, we report the first experimental observation of the inverse Doppler shift at an optical frequency (λ = 10.6 µm) by refracting a laser beam in a photonic-crystal prism that has the properties of a negative-index material.

  5. Influence of Filling Medium of Holes on the Negative-Index Response of Sandwiched Metamaterials

    Institute of Scientific and Technical Information of China (English)

    WANG Xu-Dong; YE Yong-Hong; MA Ji; JIANG Mei-Ping

    2010-01-01

    @@ We numerically study the negative index properties of sandwiched metamaterials,perforated with a square array of circle holes filled with different media.Transmission spectra indicate that the filling medium can effectively change the position of the localized resonant peak,while keeping the position of the other transmission peaks hardly changed.Reflection spectra and retrieved effective impedance verify that an appropriate choice of the filling medium can provide a perfect impedance match.Due to the perfect impedance match,the electromagnetic responses of the negative index band based on the internal surface plasmon polaritons change in many aspects,such as a stronger magnetic resonance,a higher figure of merit and a narrower negative refractive index band.

  6. Low-loss multilayered metamaterial exhibiting a negative index of refraction at visible wavelengths

    Science.gov (United States)

    Garcia-Meca, Carlos

    2012-02-01

    Over the last decade, metamaterials have attracted a great interest thanks to their potential to expand the range of electromagnetic properties found in natural materials. In particular, the possibility of achieving negative refractive index media (NIM) enables us to implement superlenses and optical storing devices. Since the first experimental demonstration at microwave frequencies, much effort has been put in extending negative refraction to the visible spectrum, where we can take full advantage of NIM properties. For instance, the superior imaging ability of NIM would be essential for visible microscopy. The desired features for NIM are low loss and isotropy. This last property includes polarization independence and negative-index behavior in all spatial directions. None of these features have been attained in previous experiments. Thus, the current challenge is to improve such aspects in order to make NIM suitable for practical applications. In this work, we experimentally demonstrate a low-loss multilayer metamaterial exhibiting a double-negative index in the visible spectrum, while presenting polarization independence at normal incidence. This has been achieved by exploiting the properties of a second-order magnetic resonance of the so-called fishnet structure, in contrast to previous works that used first-order magnetic resonances, both related to gap surface plasmon polariton (SPP) modes. The low-loss nature of the employed magnetic resonance, together with the effect of the interacting adjacent layers, results in a figure of merit as high as 3.34. A wide spectral range of negative index is achieved, covering the wavelength region between 620 and 806 nm with only two different designs. The fabricated metamaterials are the first experimental multilayer NIM in the visible spectrum, which entails an important step towards homogeneous NIM in this range. Finally, we found that the SPP modes determining the permeability resonance display weak angular dispersion.

  7. Measurement of a broadband negative index with space-coiling acoustic metamaterials.

    Science.gov (United States)

    Xie, Yangbo; Popa, Bogdan-Ioan; Zigoneanu, Lucian; Cummer, Steven A

    2013-04-26

    We report the experimental demonstration of a broadband negative refractive index obtained in a labyrinthine acoustic metamaterial structure. Two different approaches were employed to prove the metamaterial negative index nature: one-dimensional extractions of effective parameters from reflection and transmission measurements and two-dimensional prism-based measurements that convincingly show the transmission angle corresponding to negative refraction. The transmission angles observed in the latter case also agree very well with the refractive index obtained in the one-dimensional measurements and numerical simulations. We expect this labyrinthine metamaterial to become the unit cell of choice for practical acoustic metamaterial devices that require broadband and significantly negative indices of refraction.

  8. Measurement of a Broadband Negative Index with Space-Coiling Acoustic Metamaterials

    Science.gov (United States)

    Xie, Yangbo; Popa, Bogdan-Ioan; Zigoneanu, Lucian; Cummer, Steven A.

    2013-04-01

    We report the experimental demonstration of a broadband negative refractive index obtained in a labyrinthine acoustic metamaterial structure. Two different approaches were employed to prove the metamaterial negative index nature: one-dimensional extractions of effective parameters from reflection and transmission measurements and two-dimensional prism-based measurements that convincingly show the transmission angle corresponding to negative refraction. The transmission angles observed in the latter case also agree very well with the refractive index obtained in the one-dimensional measurements and numerical simulations. We expect this labyrinthine metamaterial to become the unit cell of choice for practical acoustic metamaterial devices that require broadband and significantly negative indices of refraction.

  9. Three-dimensional negative index of refraction at optical frequencies by coupling plasmonic waveguides

    CERN Document Server

    Verhagen, Ewold; L.,; Kuipers,; Polman, Albert

    2010-01-01

    We identify a route towards achieving a negative index of refraction at optical frequencies based on coupling between plasmonic waveguides that support backwards waves. We show how modal symmetry can be exploited in metal-dielectric waveguide pairs to achieve negative refraction of both phase and energy. By properly controlling coupling between adjacent waveguides, a metamaterial consisting of a one-dimensional multilayer stack exhibiting an isotropic index of -1 can be achieved at a free-space wavelength of 400 nm. The general concepts developed here may inspire new low-loss metamaterial designs operating close to the metal plasma frequency.

  10. Three-Dimensional Negative Index of Refraction at Optical Frequencies by Coupling Plasmonic Waveguides

    Science.gov (United States)

    Verhagen, Ewold; de Waele, René; Kuipers, L.; Polman, Albert

    2010-11-01

    We identify a route towards achieving a negative index of refraction at optical frequencies based on coupling between plasmonic waveguides that support backwards waves. We show how modal symmetry can be exploited in metal-dielectric waveguide pairs to achieve negative refraction of both phase and energy. Control of waveguide coupling yields a metamaterial consisting of a one-dimensional multilayer stack that exhibits an isotropic index of -1 at a free-space wavelength of 400 nm. The concepts developed here may inspire new low-loss metamaterial designs operating close to the metal plasma frequency.

  11. Numerical simulations of negative-index refraction in a lamellar composite with alternating single negative layers

    Institute of Scientific and Technical Information of China (English)

    Dong Zheng-Gao; Zhu Shi-Ning; Liu Hui

    2006-01-01

    Negative-index refraction is demonstrated in a lamellar composite with epsilon-negative (ENG) and mu-negative (MNG) materials stacked alternatively. Based on the effective medium approximation, simultaneously negative effective permittivity and permeability of such a lamellar composite are obtained theoretically and further proven by full-wave simulations. Consequently, the renowned left-handed metamaterial comprising split ring resonators and wires is interpreted as an analogy of such ENG-MNG layers. In addition, beyond the effective medium approximation, the propagating field squeezed near the ENG/MNG interface is demonstrated to be left-handed surface waves with backward phase velocity.

  12. Tunable omnidirectional multichannel filters based on dual-defective photonic crystals containing negative-index materials

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yihang, E-mail: kallenmail@sina.co [School of Physics and Telecommunication Engineering, South China Normal University, Guangzhou 510006 (China)

    2009-04-07

    Multiple defect modes may generate in one-dimensional dual-defective photonic crystals containing negative-index materials. The interference between the two kinds of defect states of the proposed structure is avoided. Therefore, the frequency, frequency interval and number of the defect modes corresponding to different kinds of defects can be tuned independently as desired. These defect modes inside the zero n-bar gap are insensitive to the incident angle. It thus opens a promising way to fabricate omnidirectional multichannel filters with specific channels.

  13. High symmetry versus optical isotropy of a negative-index metamaterial

    DEFF Research Database (Denmark)

    Menzel, Christoph; Rockstuhl, Carsten; Lliew, Rumen;

    2010-01-01

    Optically isotropic metamaterials MMs are required for the implementation of subwavelength imaging systems. At first glance one would expect that their design should be based on unit cells exhibiting a cubic symmetry being the highest crystal symmetry. It is anticipated that this is a sufficient...... in carcass negative index MM. We show that this MM is basically optically isotropic but not in the spectral domain where it exhibits negative refraction. The primary goal of this contribution is to introduce a tool that allows to probe a MM against optical isotropy....

  14. Three-dimensional negative index of refraction at optical frequencies by coupling plasmonic waveguides.

    Science.gov (United States)

    Verhagen, Ewold; de Waele, René; Kuipers, L; Polman, Albert

    2010-11-26

    We identify a route towards achieving a negative index of refraction at optical frequencies based on coupling between plasmonic waveguides that support backwards waves. We show how modal symmetry can be exploited in metal-dielectric waveguide pairs to achieve negative refraction of both phase and energy. Control of waveguide coupling yields a metamaterial consisting of a one-dimensional multilayer stack that exhibits an isotropic index of -1 at a free-space wavelength of 400 nm. The concepts developed here may inspire new low-loss metamaterial designs operating close to the metal plasma frequency.

  15. Effects of negative index medium defect layers on the trans mission properties of one-dimensional photonic crystal

    Institute of Scientific and Technical Information of China (English)

    XIANG Yuan-jiang; DAI Xiao-yu; WEN Shuang-chun

    2007-01-01

    School of Computer and Communication, Hunan University, Changsha 410082, ChinaThe photonic band gap structure of 1D photonic crystal with a negative index medium defect layer is studied by using the transfer matrix method. Investigations show that the introdution of negative index medium defect layer and the increase of the negative index value will result in an extension of the band gap. Moreover, by increasing the negative index, the width of defect layer and the numbers of period photonic crystal, the width of defect modes will be narrowed, which is advantaged to obtain optical filters with narrow band. Finally, the effects of absorption on the properties of band gap and on defect modes have been discussed.

  16. Antisymmetric PT-photonic structures with balanced positive and negative index materials

    CERN Document Server

    Ge, Li

    2012-01-01

    In this Letter we study a new class of synthetic materials in which the refractive index satisfies a special symmetry, n(-x)=-n^*(x), which we term antisymmetric parity-time (APT) systems. Unlike PT-symmetric systems which require balanced gain and loss, i.e. n(-x)=n^*(x), APT systems consist of balanced positive and negative index materials (NIMs). Despite the seemingly PT-symmetric optical potential $V(x)\\equiv n(x)^2\\omega^2/c^2$, such systems are not invariant under combined PT operation due to the discontinuity of the spatial derivative of the wavefunction. We show that APT systems display intriguing properties such as spontaneous phase transition of the scattering matrix, bidirectional invisibility, and a continuous lasing spectrum.

  17. Creating wide-band negative-index-of-refraction metamaterials with fractal-based geometry

    Science.gov (United States)

    Penney, Keith

    2009-11-01

    A burgeoning topic of modern research in electrodynamics and antenna design is the design and fabrication of ``left-handed'' metamaterials. This ``left-handedness'' is often created through use of an array of conductive structures with geometry appropriate for coupling on the wavelength scale with incident radiation to produce a phase-shifted reflected wave that cancels out incoming radiation and prevents transmission. This property has been demonstrated in several papers published in the last decade. In every instance, though the ``left-handed'' response is only exhibited in a small bandwidth centered about a specific frequency (bandwidth typically less that 0.1 GHz). I will show that through use of tessellated, fractal-based structures, one can create a repeatable geometry that exhibits a negative index of refraction (NIR) for multiple frequency bands, limited only by fabrication precision, with the ultimate goal being a wide-band absorptive response.

  18. Aberration-free two-thin-lens systems based on negative-index materials

    Institute of Scientific and Technical Information of China (English)

    Lin Zhi-Li; Ding Jie-Chen; Zhang Pu

    2008-01-01

    Since the complete correction of all five monochromatic Seidel aberrations for a singlet lens with random shape or a two-thin-lens system is unprocurable merely by using the conventional positive-index materials both in theory and practice, this paper proposes that when one or both of the two lenses is/are made from negative-index materials, an imaging system composed of a pair of spherical thin lenses is possible to form a real image, in air, free from all five monochromatic Seidel aberrations. The calculated numerical solutions to the structural parameters of such lens systems possessing superior performance are provided and examples of them are illustrated for the given combinations of the two lenses' refractive indices, including an ultimately-remote imaging system.

  19. Backward phase-matching for nonlinear optical generation in negative-index materials

    Science.gov (United States)

    Lan, Shoufeng; Kang, Lei; Schoen, David T.; Rodrigues, Sean P.; Cui, Yonghao; Brongersma, Mark L.; Cai, Wenshan

    2015-08-01

    Metamaterials have enabled the realization of unconventional electromagnetic properties not found in nature, which provokes us to rethink the established rules of optics in both the linear and nonlinear regimes. One of the most intriguing phenomena in nonlinear metamaterials is `backward phase-matching', which describes counter-propagating fundamental and harmonic waves in a negative-index medium. Predicted nearly a decade ago, this process is still awaiting a definitive experimental confirmation at optical frequencies. Here, we report optical measurements showing backward phase-matching by exploiting two distinct modes in a nonlinear plasmonic waveguide, where the real parts of the mode refractive indices are 3.4 and -3.4 for the fundamental and the harmonic waves respectively. The observed peak conversion efficiency at the excitation wavelength of ~780 nm indicates the fulfilment of the phase-matching condition of k2ω = 2kω and n2ω = -nω, where the coherent harmonic wave emerges along a direction opposite to that of the incoming fundamental light.

  20. Negative Index Refraction in the Complex Ginzburg—Landau Equation in Connection with the Experimental CIMA Reaction

    Science.gov (United States)

    Yuan, Xu-Jin

    2012-09-01

    In comparison with the phenomenon of negative index refraction observed in artificial meta-materials, it is interesting to ask if this type of behavior also exists or not in reaction-diffusion systems that support nonlinear chemical waves. Previous studies indicate that the negative index refraction could occur on a interface between a medium of a normal wave and a medium that supports anti-waves. Here we investigate the phenomenon in the complex Ginzburg—Landau equation (CGLE) in a close relationship with the quantitative model for the chloriteiodide-malonic acid (CIMA) reaction. The amplitude equation CGLE is deduced from the CIMA reaction, and simulations with mapped parameters from the reaction-diffusion equation reveal that the competition between normal waves and anti-waves on the interface determines whether the negative index refraction occurs or not.

  1. A fermionic spacetime cage

    CERN Document Server

    Lin, De-Hone

    2015-01-01

    This paper is concerned with the application of a spacetime structure to a three-dimensional quantum system. There are three components. First, the main part of this paper presents the constraint conditions which build the relation of a spacetime structure and a form invariance solution to the covariant Dirac equation. The second is to devise a spacetime cage for fermions with chosen constraints. The third part discusses the feasibility of the cage with an experiment.

  2. Ultra low-loss, isotropic 2D optical negative-index metamaterial based on hybrid metal-semiconductor nanowires

    CERN Document Server

    Paniagua-Dominguez, R; Sanchez-Gil, J A

    2012-01-01

    In the past few years, many of the fascinating and previously almost unconceivable properties predicted for those novel, artificial, man-made materials, so called metamaterials, were demonstrated to be not only a tangible reality, but a very useful one. However, plenty of the best achievements in that newly discovered field are far from having a direct translation to the, in many aspects more interesting, high frequency range, without being burdened not only by technological difficulties, but also conceptual ones. Of particular importance within the realm of optical metamaterials having a negative index of refraction, often designated negative-index metamaterials (NIM), is the issue of simultaneously achieving a strong response of the system and low associated losses. In the present work, we demonstrate the possibility to use hybrid metal-semiconductor nanowires to obtain an isotropic optical NIM, with very strong electric and magnetic responses, which exhibits extremely low losses (about two orders of magnit...

  3. A Miniaturized Antenna with Negative Index Metamaterial Based on Modified SRR and CLS Unit Cell for UWB Microwave Imaging Applications

    Directory of Open Access Journals (Sweden)

    Md. Moinul Islam

    2015-01-01

    Full Text Available A miniaturized antenna employing a negative index metamaterial with modified split-ring resonator (SRR and capacitance-loaded strip (CLS unit cells is presented for Ultra wideband (UWB microwave imaging applications. Four left-handed (LH metamaterial (MTM unit cells are located along one axis of the antenna as the radiating element. Each left-handed metamaterial unit cell combines a modified split-ring resonator (SRR with a capacitance-loaded strip (CLS to obtain a design architecture that simultaneously exhibits both negative permittivity and negative permeability, which ensures a stable negative refractive index to improve the antenna performance for microwave imaging. The antenna structure, with dimension of 16 × 21 × 1.6 mm3, is printed on a low dielectric FR4 material with a slotted ground plane and a microstrip feed. The measured reflection coefficient demonstrates that this antenna attains 114.5% bandwidth covering the frequency band of 3.4–12.5 GHz for a voltage standing wave ratio of less than 2 with a maximum gain of 5.16 dBi at 10.15 GHz. There is a stable harmony between the simulated and measured results that indicate improved nearly omni-directional radiation characteristics within the operational frequency band. The stable surface current distribution, negative refractive index characteristic, considerable gain and radiation properties make this proposed negative index metamaterial antenna optimal for UWB microwave imaging applications.

  4. Mobile Phone Faraday Cage

    CERN Document Server

    French, M M J

    2011-01-01

    A Faraday cage is an interesting physics phenomena where an electromagnetic wave can be excluded from a volume of space by enclosure with an electrically conducting material. The practical application of this in the classroom is to block the signal to a mobile phone by enclosing it in a metal can! The background of the physics behind this is described in some detail followed by a explanation of some demonstrations and experiments which I have used.

  5. Defect modes properties in periodic lossy multilayer containing negative index materials with symmetric and asymmetric geometric structures

    CERN Document Server

    Aghajamali, Alireza; Barati, Mahmood; Wu, Chien-Jang

    2014-01-01

    In this paper the characteristic matrix method is used to study the propagation of electromagnetic waves through one-dimensional lossy photonic crystals composed of negative and positive refractive index material layers with symmetric and asymmetric geometric structures with a defect layer at the center of the structure. First, the positive index material defect layer is considered, and the effects of the polarization and the angle of incidence on the defect mode in the transmission spectra of the both structures are investigated. The results show that the number of the defect modes in the transmission spectra depends on the geometry (symmetric or asymmetric) of the structure. In addition, it is shown that the defect mode frequency increases as the angle of incidence increases. This property is independent of the geometry of the structure. Then, for normal incidence, the negative index material defect layer is considered, and the properties of defect modes for both structures are investigated. The results can...

  6. High levitation pressures with cage-cooled superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Hull, John R. [Energy Technology Division, Argonne National Laboratory, Argonne, IL (United States); Komori, Mochimitsu [Department of Mechanical Systems Engineering, Kyushu Institute of Technology, Iizuka, Fukuoka (Japan)

    2002-05-01

    We present an analysis of and experimental results from a levitational system comprising a stationary, bulk high-temperature superconductor (HTS) and a levitated component (rotor) that consists of a cylindrical permanent magnet surrounded by an annular HTS. The rotor is cooled below the critical temperature of the HTS while surrounded by a ferromagnetic cage. When the ferromagnetic cage is removed, the flux from the permanent magnet is essentially excluded from the interior of the HTS. When brought into proximity with the HTS stator, the cage-cooled rotor experiences a levitational force. The levitational force may be calculated by applying magnetic circuit theory. Such calculations indicate that for a sufficiently high critical current density, the levitational pressure may exceed that between the permanent magnet and its mirror image. We constructed a rotor from an NdFeB permanent magnet and YBCO bulk HTS with a critical current density of {approx}5 kA cm{sup -2}. A soft ferromagnetic steel cage was constructed in segments. The critical current density of the stator HTS was also {approx}5 kA cm{sup -2}. Experimental results obtained with the cage-cooled rotor and stationary HTS show a significant increase in force over that of an equivalent PM rotor and stationary HTS. (author)

  7. High levitation pressures with cage-cooled superconductors

    Science.gov (United States)

    Hull, John R.; Komori, Mochimitsu

    2002-05-01

    We present an analysis of and experimental results from a levitational system comprising a stationary, bulk high-temperature superconductor (HTS) and a levitated component (rotor) that consists of a cylindrical permanent magnet surrounded by an annular HTS. The rotor is cooled below the critical temperature of the HTS while surrounded by a ferromagnetic cage. When the ferromagnetic cage is removed, the flux from the permanent magnet is essentially excluded from the interior of the HTS. When brought into proximity with the HTS stator, the cage-cooled rotor experiences a levitational force. The levitational force may be calculated by applying magnetic circuit theory. Such calculations indicate that for a sufficiently high critical current density, the levitational pressure may exceed that between the permanent magnet and its mirror image. We constructed a rotor from an NdFeB permanent magnet and YBCO bulk HTS with a critical current density of ≈5 kA cm-2. A soft ferromagnetic steel cage was constructed in segments. The critical current density of the stator HTS was also ≈5 kA cm-2. Experimental results obtained with the cage-cooled rotor and stationary HTS show a significant increase in force over that of an equivalent PM rotor and stationary HTS.

  8. Cryogenic Caging for Science Instrumentation

    Science.gov (United States)

    Penanen, Konstantin; Chui, Talso C.

    2011-01-01

    A method has been developed for caging science instrumentation to protect from pyro-shock and EDL (entry, descent, and landing) acceleration damage. Caging can be achieved by immersing the instrument (or its critical parts) in a liquid and solidifying the liquid by cooling. After the launch shock and/or after the payload has landed, the solid is heated up and evaporated.

  9. Faraday Cage Protects Against Lightning

    Science.gov (United States)

    Jafferis, W.; Hasbrouck, R. T.; Johnson, J. P.

    1992-01-01

    Faraday cage protects electronic and electronically actuated equipment from lightning. Follows standard lightning-protection principles. Whether lightning strikes cage or cables running to equipment, current canceled or minimized in equipment and discharged into ground. Applicable to protection of scientific instruments, computers, radio transmitters and receivers, and power-switching equipment.

  10. Cage-based performance capture

    CERN Document Server

    Savoye, Yann

    2014-01-01

    Nowadays, highly-detailed animations of live-actor performances are increasingly easier to acquire and 3D Video has reached considerable attentions in visual media production. In this book, we address the problem of extracting or acquiring and then reusing non-rigid parametrization for video-based animations. At first sight, a crucial challenge is to reproduce plausible boneless deformations while preserving global and local captured properties of dynamic surfaces with a limited number of controllable, flexible and reusable parameters. To solve this challenge, we directly rely on a skin-detached dimension reduction thanks to the well-known cage-based paradigm. First, we achieve Scalable Inverse Cage-based Modeling by transposing the inverse kinematics paradigm on surfaces. Thus, we introduce a cage inversion process with user-specified screen-space constraints. Secondly, we convert non-rigid animated surfaces into a sequence of optimal cage parameters via Cage-based Animation Conversion. Building upon this re...

  11. A Mobile Phone Faraday Cage

    Science.gov (United States)

    French, M. M. J.

    2011-01-01

    A Faraday cage is an interesting physical phenomenon where an electromagnetic wave can be excluded from a volume of space by enclosure with an electrically conducting material. The practical application of this in the classroom is to block the signal to a mobile phone by enclosing it in a metal can. The background of the physics behind this is…

  12. MOLECULAR DYNAMICS SIMULATIONS OF FILLED AND EMPTY CAGE-LIKE WATER CLUSTERS IN LIQUID WATER AND THEIR SIGNIFICANCE TO GAS HYDRATE FORMATION MECHANISMS

    Institute of Scientific and Technical Information of China (English)

    GUO Guangjun; ZHANG Yigang; ZHAO Yajuan

    2003-01-01

    Molecular dynamics simulations are performed to observe the evolutions of 512 and 51262 cage-like water clusters filled with or without a methane molecule immersed in bulk liquid water at 250 K and 230 K. The lifetimes of these clusters are calculated according to their Lindemann index δ (t) using the criteria of δ≥0.07. For both the filled and empty clusters, we find the dynamics of bulk water determines the lifetimes of cage-like water clusters, and that the lifetime of 512 62 cage-like cluster is the same as that of 512 cage-like cluster. Although the methane molecule indeed makes the filled cage-like cluster more stable than the empty one, the empty cage-like cluster still has chance to be long-lived compared with the filled clusters. These observations support the labile cluster hypothesis on the formation mechanisms of gas hydrates.

  13. A mobile phone Faraday cage

    Science.gov (United States)

    French, M. M. J.

    2011-05-01

    A Faraday cage is an interesting physical phenomenon where an electromagnetic wave can be excluded from a volume of space by enclosure with an electrically conducting material. The practical application of this in the classroom is to block the signal to a mobile phone by enclosing it in a metal can. The background of the physics behind this is described in some detail, and this is followed by a explanation of some demonstrations and experiments which I have used.

  14. The caged state of some small molecules in the C60 cage

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The potential energy curves of some small molecules, H2, N2, O2, F2, HF, CO and NO, in the caged state within C60 cage and in the free state have been calculated by the quantum-chemical method AM1. In this study, the focus is on the cage effect of C60, and the concept of caged state is put forward. The results show that the bond lengths in the caged states are not much different from those in their corresponding free states, but the bond intensities in the caged states are much greater than those in their corresponding free states.

  15. Polymers containing borane or carborane cage compounds and related applications

    Science.gov (United States)

    Bowen, III, Daniel E; Eastwood, Eric A

    2013-04-23

    Polymers comprising residues of cage compound monomers having at least one polyalkoxy silyl substituent are provided. The cage compound monomers are selected from borane cage compound monomers comprising at least 7 cage atoms and/or carborane cage compound monomers comprising 7 to 11 cage compound monomers. Such polymers can further comprise one or more reactive matrices and/or co-monomers covalently bound with the cage compound monomer residues. Articles of manufacture comprising such polymers are also disclosed.

  16. Anisotropy and memory during cage breaking events close to a wall

    Science.gov (United States)

    Kohl, Matthias; Härtel, Andreas; Schmiedeberg, Michael

    2016-12-01

    The slow dynamics in a glassy hard-sphere system is dominated by cage breaking events, i.e. rearrangements where a particle escapes from the cage formed by its neighboring particles. We study such events for an overdamped colloidal system by the means of Brownian dynamics simulations. While it is difficult to relate cage breaking events to structural mean field results in bulk, we show that the microscopic dynamics of particles close to a wall can be related to the anisotropic two-particle density. In particular, we study cage-breaking trajectories, mean forces on a tracked particle, and the impact of the history of trajectories. Based on our simulation results, we further construct two different one-particle random-walk models—one without and one with memory incorporated—and find the local anisotropy and the history-dependence of particles as crucial ingredients to describe the escape from a cage. Finally, our detailed study of a rearrangement event close to a wall not only reveals the memory effect of cages, but leads to a deeper insight into the fundamental mechanisms of glassy dynamics.

  17. Optical isotropic negative index metamaterials

    DEFF Research Database (Denmark)

    Menzel, Christoph; Paul, Thomas; Rockstuhl, Carsten;

    2010-01-01

    Towards isotropic metamaterials, we analyze isofrequency surfaces of the dispersion relation of high symmetry metamaterials and show that they are optically not isotropic. We achieve instead isotropic metamaterials that consist of carefully designed multiple layers....

  18. Jules Verne's Metaphor of the Iron Cage

    NARCIS (Netherlands)

    Ossewaarde, M.R.R.

    2010-01-01

    Max Weber's concept of the iron cage has become a byword in the scholarly world since the publication in 1930 of Talcott Parsons’ translation of The Protestant Ethic and the Spirit of Capitalism. What is less well-known is that Jules Verne had earlier used the iron cage metaphor in Twenty Thousand L

  19. Particle cage dynamics in flowing colloidal dispersions

    Science.gov (United States)

    Marenne, Stephanie; Morris, Jeffrey F.

    2016-11-01

    The idea of the particle in a suspension at rest being trapped in a cage formed by its neighbors, widely used to understand glassy suspensions, has been applied to freely flowing suspensions. Stokesian Dynamics, a discrete particle simulation, is used to simulate the flow of monodisperse colloidal hard sphere suspensions. The cage analogy is useful to study the nonlinear stress in the material during start-up of shear flow, where the neighbor cage deforms and breaks, and during oscillatory shear flow where, depending on the amplitude of oscillation, the particle is trapped inside the cage or escapes during the oscillation cycle. A precise statistical definition of the cage in terms of the nearest neighbor ring in the pair distribution function is developed. We examine the dependence of the cage dynamics on the volume fraction of particles and the Peclet number Pe , the ratio between shear and Brownian forces. Under flow, the cage is found to break at quite definite positions, and the structural distortion is found to be clearly related to the shear and normal stress response. The shear strain needed to break the neighbor cage depends on Pe as Brownian motion enhances the total deformation. A simple model captures the strain at the stress overshoot for start-up of steady shear.

  20. Synthesis, Chemistry, and Applications of Heterocyclic Cage Compounds (V)

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ The synthesis and chemistry of polycyclic of cage compounds have attracted considerable attention in recent years. The vast majority of the work reported in this area has dealt with carbocylic cage compounds. On the other hand, the synthesis and chemistry of heterocyclic cage compounds have received less attention. Recently, we envisioned that studies on the synthesis and chemistry of heterocyclic cage compounds can greatly expand the scopes and utilities of cage compounds.1 As part of a program that involves the synthesis, chemistry, and application of heterocyclic cage compounds, we report here the synthesis of new thia-oxa-cage compounds and the chemical nature of these thia-cages.

  1. Some exclusion cages do not exclude predators

    Directory of Open Access Journals (Sweden)

    Olga M. C. C. Ameixa

    2011-12-01

    Full Text Available Exclusion techniques, such as cages, are the most frequently used means of evaluating the efficiency of natural enemies in suppressing the abundance of their prey. The growth rates and peak densities of aphid populations within cages are usually larger than those in uncaged populations. However, cages change the microenvironment and prevent aphids from emigrating. Attempts were made to avoid the change in the microenvironment by using cages with a large (8 mm mesh. Here we test the hypothesis that because of the large mesh size, predators can easily penetrate into such cages during an experiment. Our results have shown that cages with a large (8 mm mesh size do not prevent predators from entering the cages and therefore cannot be used as “exclusion cages” for measuring the effect of predators on aphid numbers. Other methods of assessing the effectiveness of natural enemies in reducing the abundance of their prey, like removing the predators or direct observations, should be used instead.

  2. Active cage model of glassy dynamics

    Science.gov (United States)

    Fodor, Étienne; Hayakawa, Hisao; Visco, Paolo; van Wijland, Frédéric

    2016-07-01

    We build up a phenomenological picture in terms of the effective dynamics of a tracer confined in a cage experiencing random hops to capture some characteristics of glassy systems. This minimal description exhibits scale invariance properties for the small-displacement distribution that echo experimental observations. We predict the existence of exponential tails as a crossover between two Gaussian regimes. Moreover, we demonstrate that the onset of glassy behavior is controlled only by two dimensionless numbers: the number of hops occurring during the relaxation of the particle within a local cage and the ratio of the hopping length to the cage size.

  3. Bulk metamaterials: Design, fabrication and characterization

    DEFF Research Database (Denmark)

    Andryieuski, Andrei; Malureanu, Radu; Alabastri, Alessandro

    2009-01-01

    Bulk metamaterials claim a lot of attention worldwide. We report about our activity and advances in design, fabrication and characterization of metal-dielectric composites with three-dimensional lattices. The nomenclature of designs exhibiting negative index behaviour in the near infrared includes...... the generic family of so-called nested structures. Such designs allow keeping the cubic symmetry of the unit cell along with the electric and magnetic responses showed by different parts in separate. For extraction of effective parameters we employ homemade wave propagation retrieving method free from...... ambiguity generic to the standard S-parameters retrieval method. Accurateness of the method is highlighted by a set of numerical checks. To fabricate smooth metal three-dimensional structures we develop an electroless chemical technique. We present the results of silver deposition on the surface of a 30...

  4. Synthesis of Caged Bicyclic Phosphate Derivatives

    Institute of Scientific and Technical Information of China (English)

    FANG Xiao-min; OU Yu-xiang; LUO Rui-bin; WANG Yong; LIAN Dan-jun; LI Xin

    2008-01-01

    Seven caged bicyclic phosphate compounds were synthesized by using 1-oxo-4-hydroxymethy1-2,6,7-trioxa-1-pho-sphabicyclo[2.2.2] octane (PEPA) as starting material. Within them were three PEPA derivatives containing single caged bicyclic phosphate structure(1a,2a,3a), another three PEPA deviratives containing two caged bicyclic phosphate structures(1b,2b,3b) and one devirative(1c) containing three caged bicyclic phosphate structures. Structures of the products were characterized by FTIR, 1H NMR, elemental analysis and TG analysis. The reaction conditions were also discussed. Thermal analysis showed they had high thermal stability and excellent char-forming ability. Besides, these compounds had pentaerythritol bone and flame retardant elements of phosphorus, bromine or nitrogen simultaneously in their molecules, endowed them with good fire retardancy, and made them can be used as intumescent flame retardant.

  5. Working papers cage Mod 2A definitions

    Energy Technology Data Exchange (ETDEWEB)

    Sprouse, L.D.

    1969-01-30

    This report presents working papers for the Cage Mod 2A program. Cost data are presented for manpower, irradiation, nuclear fuels and targets, security, transportation, reactor start-up and reactor shutdown.

  6. NMR Evidence of Cage-to-Cage Diffusion of H2 in H2-Clathrates

    Science.gov (United States)

    Senadheera, Lasitha; Conradi, Mark

    2008-03-01

    H2 and heavy-ice at P>1 kbar and T ˜250 K form H2-D2O clathrate; four and one H2 may occupy each large (L) and small (S) cage, respectively. In H2-THF-H2O clathrate, H2 occupies singly and only S cages. Previous electronic-structure calculations estimate the barriers for H2 passage though hexagonal and pentagonal faces of cages as ˜6 and ˜25 kcal/mol, respectively. Our H2 NMR linewidth data reflect random crystal fields from frozen cage-wall D2O orientations. We find dramatic reductions in linewidth starting at 120 K (175 K) for H2-D2O (H2-TDF-D2O) indicating time-averaging of the crystal fields. Assuming Arrhenius behavior, our data imply energies for escape from L (S) cages of about ˜4 (˜6) kcal/mol. For L cages, the agreement with the calculated (cages were treated as rigid) barrier is reasonable. For H2 in S cages, in H2-TDF-D2O, the extreme disagreement with theory points to another mechanism of time-averaging, reorientations of the cage-wall D2O molecules, as suggested by previous work in TDH-H2O clathrate. Our limited NMR spectra at high T ˜145 K in H2-D2O show evidence of distinct resonances from diffusionally mobile and immobile H2 molecules, as expected.

  7. Self-Assembled Pyridine-Dipyrrolate Cages.

    Science.gov (United States)

    Zhang, Huacheng; Lee, Juhoon; Lammer, Aaron D; Chi, Xiaodong; Brewster, James T; Lynch, Vincent M; Li, Hao; Zhang, Zhan; Sessler, Jonathan L

    2016-04-06

    An inherently nonlinear pyridine dipyrrolate ligand, namely 2,6-bis(3,4-diethyl-5-carboxy-1H-pyrrol-2yl)pyridine (compound 1), is able to distinguish between different zinc(II) cation sources, namely Zn(acac)2 and Zn(OAc)2, respectively. This differentiation is manifest both in terms of the observed fluorescent behavior in mixed organic media and the reaction chemistry. Treatment of 1 with Zn(acac)2 gives rise to a cage dimer, cage-1, wherein two molecules of compound 1 act as double bridging units to connect two individual cage subunits. As inferred from X-ray crystallographic studies, this cage system consists of discrete zinc dimers with hydroxide bridges that, with the assistance of bound DMF solvent molecules, serve to fix the geometry and orientation of the pyridine dipyrrolate building blocks. When a different zinc source, Zn(OAc)2, is used to carry out an ostensibly similar complexation reaction with compound 1, an acetate-bridged 1D abacus-like cage polymer is obtained as inferred from X-ray diffraction analysis. This extended solid state structure, cage-2, contains individual zinc dimer cage submits and appears stabilized by solvent molecules (DMF) and the counteranion (acetate). Rod-like assemblies are also observed by DLS and SEM. This construct, in contrast to cage-1, proved fluorescent in mixed organic media. The structure of the ligand itself (i.e., in the absence of Zn(II)) was confirmed by X-ray crystallographic analysis and was found to assemble into a supramolecular polymer. Conversion to a dimer form was seen upon the addition of TBAOAc. On the basis of the metric parameters, the structures seen in the solid state are stabilized via hydrogen bonding interactions involving solvent molecules.

  8. Usefulness of the "CAGE" in Malaysia.

    Science.gov (United States)

    Indran, S K

    1995-04-01

    This study examines the usefulness of the "CAGE", (which is an acronym for "cut down", "annoyed", "guilty" and "eye-opener"), a 4-question screening test to identify excessive drinkers among Malaysian inpatients. The CAGE questionnaire after translation and back translation was administered to all inpatients in the General Hospital, Kuala Lumpur. The author interviewed 'blindly' all who score positive on the CAGE score and 10% of all negatives using the DSM III interview schedule for alcohol abuse dependence. The results show that the CAGE performs best at a cut-off point of 2 and above, with a sensitivity of 92%, specificity of 62%, positive predictive values of 38% and Kappa (K) of 0.37 with a DSM III R diagnosis for alcohol abuse/dependence. The poor agreement with a DSM III diagnosis indicates that the CAGE is not useful in the Malaysian population. Reasons suggested for this are: cultural factors in the Malaysian population resulting in the overrating of the question of 'guilt' by Muslims and translations into the local languages which are only the closest approximations.

  9. Temperature dependence of polyhedral cage volumes in clathrate hydrates

    Science.gov (United States)

    Chakoumakos, B.C.; Rawn, C.J.; Rondinone, A.J.; Stern, L.A.; Circone, S.; Kirby, S.H.; Ishii, Y.; Jones, C.Y.; Toby, B.H.

    2003-01-01

    The polyhedral cage volumes of structure I (sI) (carbon dioxide, methane, trimethylene oxide) and structure II (sII) (methane-ethane, propane, tetrahydrofuran, trimethylene oxide) hydrates are computed from atomic positions determined from neutron powder-diffraction data. The ideal structural formulas for sI and sII are, respectively, S2L6 ?? 46H2O and S16L???8 ?? 136H2O, where S denotes a polyhedral cage with 20 vertices, L a 24-cage, and L??? a 28-cage. The space-filling polyhedral cages are defined by the oxygen atoms of the hydrogen-bonded network of water molecules. Collectively, the mean cage volume ratio is 1.91 : 1.43 : 1 for the 28-cage : 24-cage : 20-cage, which correspond to equivalent sphere radii of 4.18, 3.79, and 3.37 A??, respectively. At 100 K, mean polyhedral volumes are 303.8, 227.8, and 158.8 A??3 for the 28-cage, 24-cage, and 20-cage, respectively. In general, the 20-cage volume for a sII is larger than that of a sI, although trimethylene oxide is an exception. The temperature dependence of the cage volumes reveals differences between apparently similar cages with similar occupants. In the case of trimethylene oxide hydrate, which forms both sI and sII, the 20-cages common to both structures contract quite differently. From 220 K, the sII 20-cage exhibits a smooth monotonic reduction in size, whereas the sI 20-cage initially expands upon cooling to 160 K, then contracts more rapidly to 10 K, and overall the sI 20-cage is larger than the sII 20-cage. The volumes of the large cages in both structures contract monotonically with decreasing temperature. These differences reflect reoriented motion of the trimethyelene oxide molecule in the 24-cage of sI, consistent with previous spectroscopic and calorimetric studies. For the 20-cages in methane hydrate (sI) and a mixed methane-ethane hydrate (sII), both containing methane as the guest molecule, the temperature dependence of the 20-cage volume in sII is much less than that in sI, but sII is overall

  10. GSM 光束在负折射率介质中的传输特性研究%Study on propagation properties of Gaussian-Schell model beams in negative index medium

    Institute of Scientific and Technical Information of China (English)

    许森东; 徐弼军

    2014-01-01

    In order to study the propagation characteristics of Gaussian-Schell model(GSM) beams in negative index medium, the analytical expression was obtained for the cross-spectral density function of GSM beam passing through negative index medium based on the matrix optics theory , diffraction integral theory and unification theory of coherence and polarization .The spectral density and the spectral coherence degree of the beam passing through the negative index medium were obtained with the formula .Numerical examples show that both the spectral density and the coherence spectral degree of GSM beam can be modulated by the frequency of the negative index medium .The results provide a new modulation method for the beam propagation .%为了研究高斯-谢尔模型光束在负折射率介质中的传输特性,利用矩阵光学理论、衍射积分理论、相干偏振统一理论推导了高斯-谢尔模型光束通过负折射率介质中传输交叉谱密度方程的解析表达式,并利用该解析表达式得到了高斯-谢尔模型光束通过负折射率介质的谱密度和谱相干度。结果表明,高斯-谢尔模型光束的谱密度和谱相干度都可以通过负折射率介质的工作频率调控。此研究结果提供了一种新的调控光传输的方法和技术。

  11. Synthesis, Chemistry, and Applications of Heterocyclic Cage Compounds (V)

    Institute of Scientific and Technical Information of China (English)

    WU; Hsien-Jen

    2001-01-01

    The synthesis and chemistry of polycyclic of cage compounds have attracted considerable attention in recent years. The vast majority of the work reported in this area has dealt with carbocylic cage compounds. On the other hand, the synthesis and chemistry of heterocyclic cage compounds have received less attention. Recently, we envisioned that studies on the synthesis and chemistry of heterocyclic cage compounds can greatly expand the scopes and utilities of cage compounds.1 As part of a program that involves the synthesis, chemistry, and application of heterocyclic cage compounds, we report here the synthesis of new thia-oxa-cage compounds and the chemical nature of these thia-cages.  ……

  12. High-throughput Transcriptome analysis, CAGE and beyond

    KAUST Repository

    Kodzius, Rimantas

    2008-11-25

    1. Current research - PhD work on discovery of new allergens - Postdoctoral work on Transcriptional Start Sites a) Tag based technologies allow higher throughput b) CAGE technology to define promoters c) CAGE data analysis to understand Transcription - Wo

  13. A caged substrate peptide for matrix metalloproteinases.

    Science.gov (United States)

    Decaneto, Elena; Abbruzzetti, Stefania; Heise, Inge; Lubitz, Wolfgang; Viappiani, Cristiano; Knipp, Markus

    2015-02-01

    Based on the widely applied fluorogenic peptide FS-6 (Mca-Lys-Pro-Leu-Gly-Leu-Dpa-Ala-Arg-NH2; Mca = methoxycoumarin-4-acetyl; Dpa = N-3-(2,4-dinitrophenyl)l-α,β-diaminopropionyl) a caged substrate peptide Ac-Lys-Pro-Leu-Gly-Lys*-Lys-Ala-Arg-NH2 (*, position of the cage group) for matrix metalloproteinases was synthesized and characterized. The synthesis implies the modification of a carbamidated lysine side-chain amine with a photocleavable 2-nitrobenzyl group. Mass spectrometry upon UV irradiation demonstrated the complete photolytic cleavage of the protecting group. Time-resolved laser-flash photolysis at 355 nm in combination with transient absorption spectroscopy determined the biphasic decomposition with τa = 171 ± 3 ms (79%) and τb = 2.9 ± 0.2 ms (21%) at pH 6.0 of the photo induced release of the 2-nitrobenzyl group. The recombinantly expressed catalytic domain of human membrane type I matrix metalloproteinase (MT1-MMP or MMP-14) was used to determine the hydrolysis efficiency of the caged peptide before and after photolysis. It turned out that the cage group sufficiently shields the peptide from peptidase activity, which can be thus controlled by UV light.

  14. Resonance spectra of caged black holes

    CERN Document Server

    Hod, Shahar

    2014-01-01

    Recent numerical studies of the coupled Einstein-Klein-Gordon system in a cavity have provided compelling evidence that {\\it confined} scalar fields generically collapse to form black holes. Motivated by this intriguing discovery, we here use analytical tools in order to study the characteristic resonance spectra of the confined fields. These discrete resonant frequencies are expected to dominate the late-time dynamics of the coupled black-hole-field-cage system. We consider caged Reissner-Nordstr\\"om black holes whose confining mirrors are placed in the near-horizon region $x_{\\text{m}}\\equiv (r_{\\text{m}}-r_+)/r_+\\ll\\tau\\equiv (r_+-r_-)/r_+$ (here $r_{\\text{m}}$ is the radius of the confining mirror and $r_{\\pm}$ are the radii of the black-hole horizons). We obtain a simple analytical expression for the fundamental quasinormal resonances of the coupled black-hole-field-cage system: $\\omega_n=-i2\\pi T_{\\text{BH}}\\cdot n[1+O(x^n_{\\text{m}}/\\tau^n)]$, where $T_{\\text{BH}}$ is the temperature of the caged black...

  15. Systemic listeriosis in caged Canaries (Serinus canarius)

    OpenAIRE

    Akanbi, Olatunde B; Breithaupt, Angele; Polster, Ulf; Alter, Thomas; Quandt, Anette; Bracke, Andreas; Teifke, Jens Peter

    2009-01-01

    Abstract The occurrence of listeriosis in 12 caged canaries is described where 50 % of the birds including the female and all the offspring died within two weeks without clinical signs. At necropsy, multifocal necrotising and partly granulomatous hepatitis, splenitis, myocarditis, interstitial nephritis, and exudative pericarditis with intralesional Listeria monocytogenes were the predominant findings as shown by histopathology and immunohistochemistry. Microbiology, serology ...

  16. Geomechanics of fracture caging in wellbores

    NARCIS (Netherlands)

    Weijermars, R.; Zhang, X.; Schultz-Ela, D.

    2013-01-01

    This study highlights the occurrence of so-called ‘fracture cages’ around underbalanced wellbores, where fractures cannot propagate outwards due to unfavourable principal stress orientations. The existence of such cages is demonstrated here by independent analytical and numerical methods. We explain

  17. Resonance spectra of caged black holes

    Energy Technology Data Exchange (ETDEWEB)

    Hod, Shahar [The Ruppin Academic Center, Emeq Hefer (Israel); The Hadassah Institute, Jerusalem (Israel)

    2014-11-15

    Recent numerical studies of the coupled Einstein-Klein-Gordon system in a cavity have provided compelling evidence that confined scalar fields generically collapse to form black holes. Motivated by this intriguing discovery, we here use analytical tools in order to study the characteristic resonance spectra of the confined fields. These discrete resonant frequencies are expected to dominate the late-time dynamics of the coupled black-hole-field-cage system. We consider caged Reissner-Nordstroem black holes whose confining mirrors are placed in the near-horizon region x{sub m} ≡ (r{sub m} - r{sub +})/r{sub +} << τ ≡ (r{sub +} - r{sub -})/r{sub +} (here r{sub m} is the radius of the confining mirror and r{sub ±} are the radii of the black-hole horizons). We obtain a simple analytical expression for the fundamental quasinormal resonances of the coupled blackhole- field-cage system: ω{sub n} = -2πT{sub BH}.n [1 + O(x{sub m}{sup n}/τ{sup n})], where T{sub BH} is the temperature of the caged black hole and n = 1, 2, 3,.. is the resonance parameter. (orig.)

  18. Functional detection of proteins by caged aptamers.

    Science.gov (United States)

    Pinto, Alessandro; Lennarz, Sabine; Rodrigues-Correia, Alexandre; Heckel, Alexander; O'Sullivan, Ciara K; Mayer, Günter

    2012-02-17

    While many diagnostic assay platforms enable the measurement of analytes with high sensitivity, most of them result in a disruption of the analyte's native structure and, thus, in loss of function. Consequently, the analyte can be used neither for further analytical assessment nor functional analysis. Herein we report the use of caged aptamers as templates during apta-PCR analysis of targets. Aptamers are short nucleic acids that fold into a well-defined three-dimensional structure in which they interact with target molecules with high affinity and specificity. Nucleic acid aptamers can also serve as templates for qPCR approaches and, thus, have been used as high affinity ligands to bind to target molecules and subsequently for quantification by qPCR, an assay format coined apta-PCR. Caged aptamers in turn refer to variants that bear one or more photolabile groups at strategic positions. The activity of caged aptamers can thus be turned on or off by light irradiation. The latter allows the mild elution of target-bound aptamers while the target's native structure and function remain intact. We demonstrate that this approach allows the quantitative and subsequently the functional assessment of analytes. Since caged aptamers can be generated emanating from virtually every available aptamer, the described approach can be generalized and adopted to any target-aptamer pair and, thus, have a broad applicability in proteomics and clinical diagnostics.

  19. Busting out of the Teacher Cage

    Science.gov (United States)

    Hess, Frederick M.

    2015-01-01

    The author lays out guidelines and suggestions for how teachers can actually become policy leaders, taken from his book, "The Cage-Busting Teacher" (Harvard Education Press, 2015). Teachers serious about leadership can get the ear of policy makers by leveraging their positional and moral authority--though they may need to be persistent…

  20. 48 CFR 204.7202-1 - CAGE codes.

    Science.gov (United States)

    2010-10-01

    ...) DLIS assigns or records and maintains CAGE codes to identify commercial and Government entities. DoD....39-M, Federal Logistics Information System (FLIS) Procedures Manual, prescribe use of CAGE codes. (b... the provision at 252.204-7001, Commercial and Government Entity (CAGE) Code Reporting, use...

  1. Multielectrode machine for making the cages of bag filters

    Energy Technology Data Exchange (ETDEWEB)

    Gordeev, F.I.; Arkov, V.G.; Boldyrev, A.F.; Sharenko, D.G.; Zhidkov, V.A.

    1986-01-01

    This paper describes an automatic multielectrode machine for making wire cages with an internal spiral. The machine automatically produces an endless cage from wire, joins the wires by multiple spot contact welding, and cuts it into pieces of desired length. The machine is illustrated and the method of making wire cages is demonstrated. The cages are used in bag filters of gas-cleaning systems. The machine can be used to form cages of 130-mm diameter from wires of 3-mm diameter. It is easy to operate and has a high output rate of 90m/h.

  2. On metallic clusters squeezed in atomic cages

    CERN Document Server

    Apostol, M

    1996-01-01

    The stability of metallic clusters of sodium (Na) in the octahedral cages of Na-doped fullerites Na6C60 and Na11C60 is discussed within a Thomas-Fermi model. It is shown that the tetrahedral Na4-cluster in Na6C60 has an electric charge of cca. +2.7 (in electron charge units), while the body-centered cubic Na9-cluster in Na11C60 is almost electrically neutral.

  3. Cathodic Cage Plasma Nitriding: An Innovative Technique

    OpenAIRE

    Sousa,R.R.M.; de Araújo, F. O.; J. A. P. da Costa; Brandim,A.S.; R. A. de Brito; C. Alves

    2012-01-01

    Cylindrical samples of AISI 1020, AISI 316, and AISI 420 steels, with different heights, were simultaneously treated by a new technique of ionic nitriding, entitled cathodic cage plasma nitriding (CCPN), in order to evaluate the efficiency of this technique to produce nitrided layers with better properties compared with those obtained using conventional ionic nitriding technique. This method is able to eliminate the edge effect in the samples, promoting a better uniformity of temperature, and...

  4. Incorporation of AgI clusters into the cages of zeolites LTA and FAU observed by optical spectra and X-ray diffraction patterns

    Science.gov (United States)

    Kodaira, Tetsuya; Ikeda, Takuji; Takeo, Harutoshi

    1999-02-01

    The loading of AgI into the cages of zeolites LTA and FAU was performed by vapor-phase adsorption. The successful incorporation of AgI clusters into the cages was confirmed by optical absorption spectra and X-ray powder diffraction patterns. Large blue shifts of the absorption edges were observed in the spectra of adsorbed AgI to both zeolites, compared with the lowest excited state of AgI in the bulk. The present observation of the shift implies that a strong quantum confinement in the photoexcited state of AgI occurs, which leads to the conclusion that AgI clusters have been formed in the cages. In the X-ray powder diffraction pattern of AgI-loaded LTA, superlattice reflection peaks are observed which cannot be assigned either to the reflection of LTA or the AgI in the bulk.

  5. Adsorption. Cage molecules to pick up the pollutants; Adsorption. Des molecules cages pour capter les polluants

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1999-12-01

    The cyclo-dextrins have the property to be cage molecules, that is to say they are able to shut up organic molecules in their structure. To use them in remedial action against pollution it is necessary to find a support on which they can be grafted. The Laboratory of organic chemistry and macromolecules from the University of Sciences and Technologies of Lilles is looking for this. The researchers have used a textile material in non weaved polypropylene, a support chemically steady that resists to aggressive media such polluted effluents. To graft the cage molecule, the technique of electrons bombing has been chosen. It produces a monomer (methacrylate of glycidyl) that allows to have a tissue bearer of epoxide functions susceptible to react with the cyclo-dextrin. The studies are continued in particular to valid the use of cage molecules on the dioxin and pesticides, and also to adapt the filter to gaseous media (volatile organic compounds, smells). (N.C.)

  6. Superconductivity in Y6Tr4Al43 (Tr = Nb, Mo, Ta) with Peanut-Shaped Cage Structure

    Science.gov (United States)

    Kase, Naoki; Satoh, Ryoh; Nakano, Tomohito; Takeda, Naoya

    2016-10-01

    Superconductivity is discovered in Y6Tr4Al43 (Tr = Nb, Mo, Ta) with a peanut-shaped cage structure at Tc = 0.86, 0.75, and 0.68 K, respectively. The superconducting state is revealed by performing electrical resistivity and specific heat measurements. The upper critical field is obtained to be 0.22 (Nb), 0.175 (Mo), and 0.15 T (Ta). A specific heat jump provides evidence of bulk superconductivity in these compounds.

  7. Multi-responsive metal-organic lantern cages in solution.

    Science.gov (United States)

    Brega, Valentina; Zeller, Matthias; He, Yufan; Lu, H Peter; Klosterman, Jeremy K

    2015-03-25

    Soluble copper-based M4L4 lantern-type metal-organic cages bearing internal amines were synthesized. The solution state integrity of the paramagnetic metal-organic cages was demonstrated using NMR, DLS, MS, and AFM spectroscopy. 1D supramolecular pillars of pre-formed cages or covalent host-guest complexes selectively formed upon treatment with 4,4'-bipyridine and acetic anhydride, respectively.

  8. Systemic listeriosis in caged canaries (Serinus canarius).

    Science.gov (United States)

    Akanbi, Olatunde B; Breithaupt, Angele; Polster, Ulf; Alter, Thomas; Quandt, Anette; Bracke, Andreas; Teifke, Jens P

    2008-06-01

    The occurrence of listeriosis in 12 caged canaries is described where 50% of the birds, including the female and all of the offspring, died within 2 weeks without clinical signs. At necropsy, multifocal necrotizing and partly granulomatous hepatitis, splenitis, myocarditis, interstitial nephritis, and exudative pericarditis with intra-lesional Listeria monocytogenes were the predominant findings as shown by histopathology and immunohistochemistry. Microbiology, serology and polymerase chain reaction revealed L. monocytogenes serotype 1/2a as the causative agent. Thus listeriosis has to be considered in the differential diagnosis for granulomas associated with mycobacteriosis, yersiniosis, coligranulomatosis or fungal infections.

  9. Genetic encoding of caged cysteine and caged homocysteine in bacterial and mammalian cells.

    Science.gov (United States)

    Uprety, Rajendra; Luo, Ji; Liu, Jihe; Naro, Yuta; Samanta, Subhas; Deiters, Alexander

    2014-08-18

    We report the genetic incorporation of caged cysteine and caged homocysteine into proteins in bacterial and mammalian cells. The genetic code of these cells was expanded with an engineered pyrrolysine tRNA/tRNA synthetase pair that accepts both light-activatable amino acids as substrates. Incorporation was validated by reporter assays, western blots, and mass spectrometry, and differences in incorporation efficiency were explained by molecular modeling of synthetase-amino acid interactions. As a proof-of-principle application, the genetic replacement of an active-site cysteine residue with a caged cysteine residue in Renilla luciferase led to a complete loss of enzyme activity; however, upon brief exposure to UV light, a >150-fold increase in enzymatic activity was observed, thus showcasing the applicability of the caged cysteine in live human cells. A simultaneously conducted genetic replacement with homocysteine yielded an enzyme with greatly reduced activity, thereby demonstrating the precise probing of a protein active site. These discoveries provide a new tool for the optochemical control of protein function in mammalian cells and expand the set of genetically encoded unnatural amino acids.

  10. Effect of cage configuration in structural and optical properties of tin films grown by cathodic cage discharge

    Directory of Open Access Journals (Sweden)

    Natália de Freitas Daudt

    2013-01-01

    Full Text Available Cathodic cage discharge was developed recently in order to eliminate phenomena as edge effect and overheating, which occurs during conventional processes. In this study, the effect of cage configuration in active species during the deposition process and optical properties of TiN film were studied. TiN compound was chosen because its optical properties are very sensitive to slight variations in microstructure and film thickness, becoming a good monitoring tool in fabrication process control. Cages were made of titanium and have different holes numbers and holes diameter. Electrical efficiency of the system and optical properties of TiN films were strongly influenced by experimental conditions. It was found that with more holes at the top of cage, deposition rate and crystallinity were higher, if compared to cages with a small number of holes at the top. On the other hand, the opposite behavior was observed when more holes were located at the sidewall of cage.

  11. Preinjector for Linac 1, Faraday cage

    CERN Multimedia

    1974-01-01

    The 50 MeV Linac 1 started up in 1958 as injector to the 26 GeV PS, with a 520 kV Cockcroft-Walton generator as its preinjector, housed in a vast Faraday cage, visible here. When the Cockcroft-Walton broke down in 1973, it was replaced by a much smaller SAMES generator, of the kind used for electrostatic separators. From 1980 on, Linac 2 took over as injector for the 800 MeV Booster, and Linac 1 continued as injector for LEAR. In 1984, the electrostatic preinjector (i.e. the Faraday cage with its contents, SAMES generator and all) was replaced by a 520 keV RFQ. At the lower left corner we see the HV connectors to the SAMES generator, at the right edge part of the opened electronics-platform. Jean-Luc Vallet sees to it that all parts are properly grounded. See also 7403073X, 7403074X, 7403081X, 7403083X.

  12. Computed tomography measurement of rib cage morphometry in emphysema.

    Directory of Open Access Journals (Sweden)

    Nicola Sverzellati

    Full Text Available BACKGROUND: Factors determining the shape of the human rib cage are not completely understood. We aimed to quantify the contribution of anthropometric and COPD-related changes to rib cage variability in adult cigarette smokers. METHODS: Rib cage diameters and areas (calculated from the inner surface of the rib cage in 816 smokers with or without COPD, were evaluated at three anatomical levels using computed tomography (CT. CTs were analyzed with software, which allows quantification of total emphysema (emphysema%. The relationship between rib cage measurements and anthropometric factors, lung function indices, and %emphysema were tested using linear regression models. RESULTS: A model that included gender, age, BMI, emphysema%, forced expiratory volume in one second (FEV1%, and forced vital capacity (FVC% fit best with the rib cage measurements (R(2 = 64% for the rib cage area variation at the lower anatomical level. Gender had the biggest impact on rib cage diameter and area (105.3 cm(2; 95% CI: 111.7 to 98.8 for male lower area. Emphysema% was responsible for an increase in size of upper and middle CT areas (up to 5.4 cm(2; 95% CI: 3.0 to 7.8 for an emphysema increase of 5%. Lower rib cage areas decreased as FVC% decreased (5.1 cm(2; 95% CI: 2.5 to 7.6 for 10 percentage points of FVC variation. CONCLUSIONS: This study demonstrates that simple CT measurements can predict rib cage morphometric variability and also highlight relationships between rib cage morphometry and emphysema.

  13. Abnormal Behavior in Relation to Cage Size in Rhesus Monkeys

    Science.gov (United States)

    Paulk, H. H.; And Others

    1977-01-01

    Examines the effects of cage size on stereotyped and normal locomotion and on other abnormal behaviors in singly caged animals, whether observed abnormal behaviors tend to co-occur, and if the development of an abnormal behavior repertoire leads to reduction in the number of normal behavior categories. (Author/RK)

  14. Teaching in the Institutional Cage: Metaphor and Collateral Oppression

    Science.gov (United States)

    Noël Smith, Becky L.

    2014-01-01

    This analysis is a philosophical exploration of Marilyn Frye's metaphor of the cage and Patricia Hill Collins' theory of intersecting oppressions. It argues that social structures and forms of oppressive knowledge make up the individual wires on each person's cage and that these work to confine individuals, particularly those in the…

  15. Dynamic Combinatorial Libraries of Disulfide Cages in Water

    NARCIS (Netherlands)

    West, Kevin R.; Bake, Kyle D.; Otto, Sijbren

    2005-01-01

    Dynamic combinatorial libraries (DCLs) containing water-soluble disulfide-linked cages (alongside macrocyclic structures) have been generated and characterized. Unlike most other strategies for generating molecular cages, the structures are held together by covalent bonds, which are formed under the

  16. Design of the UHVDC Corona Cage in China

    Institute of Scientific and Technical Information of China (English)

    GUO Jian; LU Jiayu; ZHANG Wenliang

    2013-01-01

    For the purpose of testing and analysing the corona characteristics of UHVDC bundle conductors,UHVDC corona cage would be built in China.Corona cage is one of the indispensable equipments for conductor corona performance researches.Tests of conductor cotona characteristics in corona cages can overcome the shortages of those with test lines.The dimensions of several corona cages constructed overseas were introduced in this paper.Based on foreign experiences and the requirement of State Grid Corporation of China,the UHVDC corona cage was designed as double-cage,double-layer,three-seetions,and catenary shape with the size of 70 m×22 m× 13 m.The corona loss measurement system,radio interference measuring system,and the audible noise measuring system are also detailed,including the measurement theory,connection with the cage,the parameters and the designing basis.The UHVDC corona cage has been put into service.It now undergoes a large amount of audible noise and radio frequency interference tests.

  17. Photoactivatable Caged Prodrugs of VEGFR-2 Kinase Inhibitors

    Directory of Open Access Journals (Sweden)

    Boris Pinchuk

    2016-04-01

    Full Text Available In this study, we report on the design, synthesis, photokinetic properties and in vitro evaluation of photoactivatable caged prodrugs for the receptor tyrosine kinase VEGFR-2. Highly potent VEGFR-2 inhibitors 1 and 3 were caged by introduction of a photoremovable protecting group (PPG to yield the caged prodrugs 4 and 5. As expected, enzymatic and cellular proliferation assays showed dramatically diminished efficacy of caged prodrugs in vitro. Upon ultraviolet (UV irradiation of the prodrugs original inhibitory activity was completely restored and even distinctly reinforced, as was the case for the prodrug 4. The presented results are a further evidence for caging technique being an interesting approach in the protein kinase field. It could enable spatial and temporal control for the inhibition of VEGFR-2. The described photoactivatable prodrugs might be highly useful as biological probes for studying the VEGFR-2 signal transduction.

  18. Organic cage compounds--from shape-persistency to function.

    Science.gov (United States)

    Zhang, Gang; Mastalerz, Michael

    2014-03-21

    Defined cavities are found in biological systems, such as in enzymes to accelerate specific reactions with specific molecular targets, or as transport containers for molecular cargoes. Chemists have been inspired by those phenomena found in nature and synthesized defined cage compounds for different purposes, such as for stabilizing reactive intermediates, running reactions within the cavities or studying recognition events. However, most cage compounds are based on the coordination of metal ions, and only a few are charge neutral. Purely organic cages are usually charge neutral and more stable due to existing covalent bonds. Covalent bonds can be made in two ways, applying irreversible reactions or reversible reactions. By introducing dynamic covalent chemistry (DCC), cages have become accessible in good yields from rather simple precursors. Here, we compare both methods and highlight those that give very good yields. Furthermore, the use of organic cage compounds in sorption, recognition, sensing, separation and stabilization of molecules will be discussed.

  19. Transcription regulatory networks analysis using CAGE

    KAUST Repository

    Tegnér, Jesper N.

    2009-10-01

    Mapping out cellular networks in general and transcriptional networks in particular has proved to be a bottle-neck hampering our understanding of biological processes. Integrative approaches fusing computational and experimental technologies for decoding transcriptional networks at a high level of resolution is therefore of uttermost importance. Yet, this is challenging since the control of gene expression in eukaryotes is a complex multi-level process influenced by several epigenetic factors and the fine interplay between regulatory proteins and the promoter structure governing the combinatorial regulation of gene expression. In this chapter we review how the CAGE data can be integrated with other measurements such as expression, physical interactions and computational prediction of regulatory motifs, which together can provide a genome-wide picture of eukaryotic transcriptional regulatory networks at a new level of resolution. © 2010 by Pan Stanford Publishing Pte. Ltd. All rights reserved.

  20. Cathodic Cage Plasma Nitriding: An Innovative Technique

    Directory of Open Access Journals (Sweden)

    R. R. M. de Sousa

    2012-01-01

    Full Text Available Cylindrical samples of AISI 1020, AISI 316, and AISI 420 steels, with different heights, were simultaneously treated by a new technique of ionic nitriding, entitled cathodic cage plasma nitriding (CCPN, in order to evaluate the efficiency of this technique to produce nitrided layers with better properties compared with those obtained using conventional ionic nitriding technique. This method is able to eliminate the edge effect in the samples, promoting a better uniformity of temperature, and consequently, a smaller variation of the thickness/height relation can be obtained. The compound layers were characterized by X-ray diffraction, optical microscopy, and microhardness test profile. The results were compared with the properties of samples obtained with the conventional nitriding, for the three steel types. It was verified that samples treated by CCPN process presented, at the same temperature, a better uniformity in the thickness and absence of the edge effect.

  1. Evaluation of unilateral cage-instrumented fixation for lumbar spine

    Directory of Open Access Journals (Sweden)

    Chen Hung-Yi

    2010-11-01

    Full Text Available Abstract Background To investigate how unilateral cage-instrumented posterior lumbar interbody fusion (PLIF affects the three-dimensional flexibility in degenerative disc disease by comparing the biomechanical characteristics of unilateral and bilateral cage-instrumented PLIF. Methods Twelve motion segments in sheep lumbar spine specimens were tested for flexion, extension, axial rotation, and lateral bending by nondestructive flexibility test method using a nonconstrained testing apparatus. The specimens were divided into two equal groups. Group 1 received unilateral procedures while group 2 received bilateral procedures. Laminectomy, facectomy, discectomy, cage insertion and transpedicle screw insertion were performed sequentially after testing the intact status. Changes in range of motion (ROM and neutral zone (NZ were compared between unilateral and bilateral cage-instrumented PLIF. Results Both ROM and NZ, unilateral cage-instrumented PLIF and bilateral cage-instrumented PLIF, transpedicle screw insertion procedure did not revealed a significant difference between flexion-extension, lateral bending and axial rotation direction except the ROM in the axial rotation. The bilateral group's ROM (-1.7 ± 0. 8 of axial rotation was decreased significantly after transpedicle screw insertion procedure in comparison with the unilateral group (-0.2 ± 0.1. In the unilateral cage-instrumented PLIF group, the transpedicle screw insertion procedure did not demonstrate a significant difference between right and left side in the lateral bending and axial rotation direction. Conclusions Based on the results of this study, unilateral cage-instrumented PLIF and bilateral cage-instrumented PLIF have similar stability after transpedicle screw fixation in the sheep spine model. The unilateral approach can substantially reduce exposure requirements. It also offers the biomechanics advantage of construction using anterior column support combined with pedicle

  2. In-situ bioassays using caged bivalves

    Energy Technology Data Exchange (ETDEWEB)

    Salazar, M.H.; Salazar, S.M.

    1995-12-31

    It is important to make the distinction between chemical measurements to assess bioaccumulation potential versus biological measurements to assess potential bioeffects because bioaccumulation is not a bioeffect. Caging provides a unique opportunity to make synoptic measurements of each and facilitates making these measurements over space and time. Measuring bioaccumulation in resident and transplanted bivalves has probably been the most frequently used form of an in-situ bioassay because bivalves concentrate chemicals in their tissues. They are also easy to collect, cage, and measure. The authors have refined bivalve bioassay methods by minimizing the size range of test animals, making repetitive measurements of the same individuals, and standardizing test protocols for a variety of applications. They are now attempting to standardize criteria for accepting and interpreting data in the same way that laboratory bioassays have been standardized. Growth measurements can serve two purposes in this assessment strategy: (1) An integrated biological response endpoint that is easily quantifiable and with significance to the population, and (2) A means of calibrating bioaccumulation by assessing the relative health and physiological state of tissues that have accumulated the chemicals. In general, the authors have found the highest bioconcentration factors associated with the highest growth rates, the highest concentrations ({micro}g/g) of chemicals in juvenile mussels, and the highest chemical content ({micro}g/animal) in adult mussels. Without accounting for possible dilution of chemical concentrations by tissue growth or magnification through degrowth, contaminant concentrations can be misleading. Examples are provided for the Sudbury River in Massachusetts (Elliptio complanata), San Diego Bay (Mytilus galloprovincialis), and the Harbor Island Superfund Site in Puget Sound (Mytilus trossulus).

  3. A novel vented microisolation container for caging animals: microenvironmental comfort in a closed-system filter cage.

    Science.gov (United States)

    Rivard, G F; Neff, D E; Cullen, J F; Welch, S W

    2000-01-01

    We designed a closed-system cage with vent ports that would allow continuous airflow in the occupied cage to ensure adequate ventilation and gas exchange. In this system, the metabolic heat loads of mice generate upward thermal air currents. Heat exits via the exhaust port, and room air enters via the intake port, providing adequate ventilation. Simulations based on computational fluid dynamics (CFD) helped us to optimize the cage's design. CFD simulations and smoke visualizations with a feeder-trough assembly illustrated the one-pass air circulation pattern and the lack of air recirculation, turbulence, and dead air space in our system. We used hot-film anemometry and smoke-test methodologies to show that adequate ventilation was provided. In a room with still air (0 air changes per hour [ACH]), a cage fitted with double wire-cloth filters (40 mesh size) and occupied by five mice has at least 12 ACH, whereas the same cage occupied by one mouse has 6 ACH. After five mice had occupied the cage for a week, its average temperature was 0.58C, relative humidity was 34%, and ammonia concentration was 3 ppm higher than that of the room. Our novel vented microisolation cage provides adequate intracage ACH, isolates mice from environmental contaminants, and contains allergenic particles within the cage in an environment appropriate for the species.

  4. Large area bulk superconductors

    Science.gov (United States)

    Miller, Dean J.; Field, Michael B.

    2002-01-01

    A bulk superconductor having a thickness of not less than about 100 microns is carried by a polycrystalline textured substrate having misorientation angles at the surface thereof not greater than about 15.degree.; the bulk superconductor may have a thickness of not less than about 100 microns and a surface area of not less than about 50 cm.sup.2. The textured substrate may have a thickness not less than about 10 microns and misorientation angles at the surface thereof not greater than about 15.degree.. Also disclosed is a process of manufacturing the bulk superconductor and the polycrystalline biaxially textured substrate material.

  5. Negative Index of Refraction in Optical Metamaterials

    CERN Document Server

    Shalaev, V M; Chettiar, U; Yuan, H K; Sarychev, A K; Drachev, V P; Kildishev, A V; Shalaev, Vladimir M.; Cai, Wenshan; Chettiar, Uday; Yuan, Hsiao-Kuan; Sarychev, Andrey K.; Drachev, Vladimir P.; Kildishev, Alexander V.

    2005-01-01

    An array of pairs of parallel gold nanorods is shown to have a negative refractive index in the optical range, close to a wavelength of 1 micron. Such behavior results from the plasmon resonance in the pairs of nanorods for both the electric and magnetic components of light. The metal rods act as inductive elements whereas the dielectric gaps perform as capacitive elements, forming an optical LC-circuit. Our experiments and simulations demonstrate the resonant behavior for an index of refraction. Above the resonance, the refractive index becomes negative. Paired metal nanorods open new opportunities for developing negative-refraction materials in optics.

  6. The planimetric unfold method of fullerene cage structure

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Two kinds of planimetric diagrams, which consist of the boat form F6 and F5, the storm petrel form F6 and F5, respectively, were proposed to express the geometric structure of fullerene cage in this study. There are two chief advantages using the diagrams: (ⅰ) the spatial symmetrical characteristic of fullerene cage is not destroyed; (ⅱ) the coordination forms of F5 and F6 in the structure can be clearly expressed. This work has laid the foundation for studying the structural geometry of fullerene cage and its quantum chemistry and property.

  7. Linear diffusion into a Faraday cage.

    Energy Technology Data Exchange (ETDEWEB)

    Warne, Larry Kevin; Lin, Yau Tang; Merewether, Kimball O.; Chen, Kenneth C.

    2011-11-01

    Linear lightning diffusion into a Faraday cage is studied. An early-time integral valid for large ratios of enclosure size to enclosure thickness and small relative permeability ({mu}/{mu}{sub 0} {le} 10) is used for this study. Existing solutions for nearby lightning impulse responses of electrically thick-wall enclosures are refined and extended to calculate the nearby lightning magnetic field (H) and time-derivative magnetic field (HDOT) inside enclosures of varying thickness caused by a decaying exponential excitation. For a direct strike scenario, the early-time integral for a worst-case line source outside the enclosure caused by an impulse is simplified and numerically integrated to give the interior H and HDOT at the location closest to the source as well as a function of distance from the source. H and HDOT enclosure response functions for decaying exponentials are considered for an enclosure wall of any thickness. Simple formulas are derived to provide a description of enclosure interior H and HDOT as well. Direct strike voltage and current bounds for a single-turn optimally-coupled loop for all three waveforms are also given.

  8. Multiexpandable cage for minimally invasive posterior lumbar interbody fusion

    Science.gov (United States)

    Coe, Jeffrey D; Zucherman, James F; Kucharzyk, Donald W; Poelstra, Kornelis A; Miller, Larry E; Kunwar, Sandeep

    2016-01-01

    The increasing adoption of minimally invasive techniques for spine surgery in recent years has led to significant advancements in instrumentation for lumbar interbody fusion. Percutaneous pedicle screw fixation is now a mature technology, but the role of expandable cages is still evolving. The capability to deliver a multiexpandable interbody cage with a large footprint through a narrow surgical cannula represents a significant advancement in spinal surgery technology. The purpose of this report is to describe a multiexpandable lumbar interbody fusion cage, including implant characteristics, intended use, surgical technique, preclinical testing, and early clinical experience. Results to date suggest that the multiexpandable cage allows a less invasive approach to posterior/transforaminal lumbar interbody fusion surgery by minimizing iatrogenic risks associated with static or vertically expanding interbody prostheses while providing immediate vertebral height restoration, restoration of anatomic alignment, and excellent early-term clinical results. PMID:27729817

  9. Homogenized boundary conditions and resonance effects in Faraday cages

    Science.gov (United States)

    Hewett, D. P.; Hewitt, I. J.

    2016-05-01

    We present a mathematical study of two-dimensional electrostatic and electromagnetic shielding by a cage of conducting wires (the so-called `Faraday cage effect'). Taking the limit as the number of wires in the cage tends to infinity, we use the asymptotic method of multiple scales to derive continuum models for the shielding, involving homogenized boundary conditions on an effective cage boundary. We show how the resulting models depend on key cage parameters such as the size and shape of the wires, and, in the electromagnetic case, on the frequency and polarization of the incident field. In the electromagnetic case, there are resonance effects, whereby at frequencies close to the natural frequencies of the equivalent solid shell, the presence of the cage actually amplifies the incident field, rather than shielding it. By appropriately modifying the continuum model, we calculate the modified resonant frequencies, and their associated peak amplitudes. We discuss applications to radiation containment in microwave ovens and acoustic scattering by perforated shells.

  10. Homogenized boundary conditions and resonance effects in Faraday cages

    Science.gov (United States)

    Hewitt, I. J.

    2016-01-01

    We present a mathematical study of two-dimensional electrostatic and electromagnetic shielding by a cage of conducting wires (the so-called ‘Faraday cage effect’). Taking the limit as the number of wires in the cage tends to infinity, we use the asymptotic method of multiple scales to derive continuum models for the shielding, involving homogenized boundary conditions on an effective cage boundary. We show how the resulting models depend on key cage parameters such as the size and shape of the wires, and, in the electromagnetic case, on the frequency and polarization of the incident field. In the electromagnetic case, there are resonance effects, whereby at frequencies close to the natural frequencies of the equivalent solid shell, the presence of the cage actually amplifies the incident field, rather than shielding it. By appropriately modifying the continuum model, we calculate the modified resonant frequencies, and their associated peak amplitudes. We discuss applications to radiation containment in microwave ovens and acoustic scattering by perforated shells. PMID:27279775

  11. Caged Protein Prenyltransferase Substrates: Tools for Understanding Protein Prenylation

    Energy Technology Data Exchange (ETDEWEB)

    DeGraw, Amanda J.; Hast, Michael A.; Xu, Juhua; Mullen, Daniel; Beese, Lorena S.; Barany, George; Distefano, Mark D. (Duke); (UMM)

    2010-11-15

    Originally designed to block the prenylation of oncogenic Ras, inhibitors of protein farnesyltransferase currently in preclinical and clinical trials are showing efficacy in cancers with normal Ras. Blocking protein prenylation has also shown promise in the treatment of malaria, Chagas disease and progeria syndrome. A better understanding of the mechanism, targets and in vivo consequences of protein prenylation are needed to elucidate the mode of action of current PFTase (Protein Farnesyltransferase) inhibitors and to create more potent and selective compounds. Caged enzyme substrates are useful tools for understanding enzyme mechanism and biological function. Reported here is the synthesis and characterization of caged substrates of PFTase. The caged isoprenoid diphosphates are poor substrates prior to photolysis. The caged CAAX peptide is a true catalytically caged substrate of PFTase in that it is to not a substrate, yet is able to bind to the enzyme as established by inhibition studies and X-ray crystallography. Irradiation of the caged molecules with 350 nm light readily releases their cognate substrate and their photolysis products are benign. These properties highlight the utility of those analogs towards a variety of in vitro and in vivo applications.

  12. Homogenized boundary conditions and resonance effects in Faraday cages.

    Science.gov (United States)

    Hewett, D P; Hewitt, I J

    2016-05-01

    We present a mathematical study of two-dimensional electrostatic and electromagnetic shielding by a cage of conducting wires (the so-called 'Faraday cage effect'). Taking the limit as the number of wires in the cage tends to infinity, we use the asymptotic method of multiple scales to derive continuum models for the shielding, involving homogenized boundary conditions on an effective cage boundary. We show how the resulting models depend on key cage parameters such as the size and shape of the wires, and, in the electromagnetic case, on the frequency and polarization of the incident field. In the electromagnetic case, there are resonance effects, whereby at frequencies close to the natural frequencies of the equivalent solid shell, the presence of the cage actually amplifies the incident field, rather than shielding it. By appropriately modifying the continuum model, we calculate the modified resonant frequencies, and their associated peak amplitudes. We discuss applications to radiation containment in microwave ovens and acoustic scattering by perforated shells.

  13. Bulk chemicals from biomass

    NARCIS (Netherlands)

    Haveren, van J.; Scott, E.L.; Sanders, J.P.M.

    2008-01-01

    Given the current robust forces driving sustainable production, and available biomass conversion technologies, biomass-based routes are expected to make a significant impact on the production of bulk chemicals within 10 years, and a huge impact within 20-30 years. In the Port of Rotterdam there is a

  14. Multicomponent Protein Cage Architectures for Photocatalysis

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Arunava [Univ. of Alabama, Tuscaloosa, AL (United States); Prevelige, Peter E [Univ. of Alabama, Birmingham, AL (United States)

    2016-01-04

    The primary goal of the project was to develop protein-templated approaches for the synthesis and directed assembly of semiconductor nanomaterials that are efficient for visible light absorption and hydrogen production. In general, visible-light-driven photocatalysis reactions exhibit low quantum efficiency for solar energy conversion primarily because of materials-related issues and limitations, such as the control of the band gap, band structure, photochemical stability, and available reactive surface area of the photocatalyst. Synthesis of multicomponent hierarchical nano-architectures, consisting of semiconductor nanoparticles (NPs) with desired optical properties fabricated to maximize spatial proximity for optimum electron and energy transfer represents an attractive route for addressing the problem. Virus capsids are highly symmetrical, self-assembling protein cage nanoparticles that exist in a range of sizes and symmetries. Selective deposition of inorganic, by design, at specific locations on virus capsids affords precise control over the size, spacing, and assembly of nanomaterials, resulting in uniform and reproducible nano-architectures. We utilized the self-assembling capabilities of the 420 subunit, 60 nm icosahedral, P22 virus capsid to direct the nucleation, growth, and proximity of a range of component materials. Controlled fabrication on the exterior of the temperature stable shell was achieved by genetically encoding specific binding peptides into an externally exposed loop which is displayed on each of the 420 coat protein subunits. Localization of complimentary materials to the interior of the particle was achieved through the use “scaffolding-fusion proteins. The scaffolding domain drives coat protein polymerization resulting in a coat protein shell surrounding a core of approximately 300 scaffolding/fusion molecules. The fusion domain comprises a peptide which specifically binds the semiconductor material of interest.

  15. Automated home cage observations as a tool to measure the effects of wheel running on cage floor locomotion.

    Science.gov (United States)

    de Visser, Leonie; van den Bos, Ruud; Spruijt, Berry M

    2005-05-28

    This paper introduces automated observations in a modular home cage system as a tool to measure the effects of wheel running on the time distribution and daily organization of cage floor locomotor activity in female C57BL/6 mice. Mice (n = 16) were placed in the home cage system for 6 consecutive days. Fifty percent of the subjects had free access to a running wheel that was integrated in the home cage. Overall activity levels in terms of duration of movement were increased by wheel running, while time spent inside a sheltering box was decreased. Wheel running affected the hourly pattern of movement during the animals' active period of the day. Mice without a running wheel, in contrast to mice with a running wheel, showed a clear differentiation between novelty-induced and baseline levels of locomotion as reflected by a decrease after the first day of introduction to the home cage. The results are discussed in the light of the use of running wheels as a tool to measure general activity and as an object for environmental enrichment. Furthermore, the possibilities of using automated home cage observations for e.g. behavioural phenotyping are discussed.

  16. CAGE BREEDING OF WARM WATER FRESHWATER FISH SPECIES

    Directory of Open Access Journals (Sweden)

    Roman Safner

    2008-10-01

    Full Text Available In the 1970s, Croatia became actively involved in the contemporary trend of breeding fish in floating cages. In addition to various species of marine fishes, breeding was attempted with trout, carp, catfish, cisco and salmon. Of the above freshwater fish species, specific standards were established only for the cage breeding of rainbow trout. Cage breeding of the remaining species remained at the level of occasional attempts, with more of an experimental than a commercial character. The regular attempts to master this technique for cage breeding of warm water freshwater fish species were aimed at achieving the known benefits of such breeding, such as simplicity of implementing technological measures, easier establishment of the breeding system, simpler manipulation, the possibility of denser colonies per unit volume with a high level of production, easier adaptations to market conditions and fewer initial structural investments. Despite the many advantages, the main reasons for the lack of greater implementation of the cage breeding technology for warm water species of freshwater fish include problems in obtaining the appropriate category and quantity of healthy fry, the specificity and applicability of physical and chemical properties of the recipients and human error. In evaluating the advantages and disadvantages, the final decision on the justification of cage breeding for individual warm water freshwater species must be based on both biological and economic factors. Based on the knowledge of cage breeding acquired to date, the rule for virtually all intensive breeding systems is that it is only recommended for those species with high market demand and a high market price. The technology that demands nutrition with highly concentrated feed and other production expenditures is costly, and is therefore not profitable with less expensive fish species. Furthermore, production must be market oriented, i.e. the appropriate market research measures

  17. Radiative Bulk Viscosity

    CERN Document Server

    Chen, X

    2001-01-01

    Viscous resistance to changes in the volume of a gas arises when different degrees of freedom have different relaxation times. Collisions tend to oppose the resulting departures from equilibrium and, in so doing, generate entropy. Even for a classical gas of hard spheres, when the mean free paths or mean flight times of constituent particles are long, we find a nonvanishing bulk viscosity. Here we apply a method recently used to uncover this result for a classical rarefied gas to radiative transfer theory and derive an expression for the radiative stress tensor for a gray medium with absorption and Thomson scattering. We determine the transport coefficients through the calculation of the comoving entropy generation. When scattering dominates absorption, the bulk viscosity becomes much larger than either the shear viscosity or the thermal conductivity.

  18. Application of Taguchi method in optimization of cervical ring cage.

    Science.gov (United States)

    Yang, Kai; Teo, Ee-Chon; Fuss, Franz Konstantin

    2007-01-01

    The Taguchi method is a statistical approach to overcome the limitation of the factorial and fractional factorial experiments by simplifying and standardizing the fractional factorial design. The objective of the current study is to illustrate the procedures and strengths of the Taguchi method in biomechanical analysis by using a case study of a cervical ring cage optimization. A three-dimensional finite element (FE) model of C(5)-C(6) with a generic cervical ring cage inserted was modelled. Taguchi method was applied in the optimization of the cervical ring cage in material property and dimensions for producing the lowest stress on the endplate to reduce the risk of cage subsidence, as in the following steps: (1) establishment of objective function; (2) determination of controllable factors and their levels; (3) identification of uncontrollable factors and test conditions; (4) design of Taguchi crossed array layout; (5) execution of experiments according to trial conditions; (6) analysis of results; (7) determination of optimal run; (8) confirmation of optimum run. The results showed that a cage with larger width, depth and wall thickness can produce the lower von Mises stress under various conditions. The contribution of implant materials is found trivial. The current case study illustrates that the strengths of the Taguchi method lie in (1) consistency in experimental design and analysis; (2) reduction of time and cost of experiments; (3) robustness of performance with removing the noise factors. The Taguchi method will have a great potential application in biomechanical field when factors of the issues are at discrete level.

  19. The theory of the bird-cage resonator

    Science.gov (United States)

    Tropp, James

    Circuit equations for the low-pass bird-cage resonator are solved to yield a two-parameter expression for the resonant frequencies; good agreement with experiment is shown for a bird cage of eight meshes. A theory of the driven bird-cage coil is given, which describes capacitive or inductive drive schemes, neglecting perturbations of coil symmetry due to the drive reactance. The theory shows how the polarization plane of the B field of a perfectly symmetrical bird cage can be rotated arbitrarily about the resonator's cylinder axis. Deviations from ideal symmetry, due to imperfect construction or trimming reactances, are then treated by perturbation theory. It is shown that in first order, the perturbation does not disturb the sinusoidal current distribution of the bird cage, although it does polarize that distribution along a direction fixed by the positions of the perturbing elements. The measured and calculated polarization directions are shown to agree to within experimental error; the measured frequency shifts due to perturbation are within 10% of those calculated. It is shown that two identical perturbations in space quadrature produce eigenstates with no spatial polarization, i.e., circularly traveling current waves.

  20. PROBLEMS OF BIOFOULING ON FISH–CAGE NETS IN AQUACULTURE

    Directory of Open Access Journals (Sweden)

    Merica Slišković

    2002-09-01

    Full Text Available Biofouling on fish–cage netting is a serious technical and economical problem to aquaculture worldwide. Compensation for the effects of biofouling must be included in cage system design and planning, as fouling can dramatically increase both weight and drag. Settlements of sessile plants and animals, with accumulation of the detritus diminish the size of mesh and can rapidly occlude mesh. Negative effect of smaller mesh size is changing in water flow trough the cages. Biofouling problems necessitating purchase of a second sets of nets or more, and frequent cleaning and changing of biofouling. Changing and cleaning frequency depend on many factors such as: location of cages (near the coast or off shore, productivity of that location, time of the year, time period in which the cages are placed on that location (cause of loading of phosphorus and nitrogen from the unconsumed food in the sediment. Net changing and cleaning procedures are labor and capital intensive. Process of the cleaning of the nets is inadequate, especially when there isnžt adequate equipment available as it is case in smaller aquaculture industry. Chemical control of biofouling e. g. use of antifoulants is questioningly cause of their possible negative effects on breeding species and environment.

  1. A laboratory cage for foster nursing newborn mice

    Directory of Open Access Journals (Sweden)

    S. Marques-de-Araújo

    1999-03-01

    Full Text Available We describe a cage to be used for foster nursing in order to guarantee that original mother's colostrum is not ingested by the newborn mice. A common (30.5 cm x 19.5 cm x 12.0 cm mouse cage was fitted with a wire net tray with a mesh (1 cm x 1 cm, which divides the cage into an upper and a lower compartment. Mice born to females placed in the upper compartment pass through the mesh and fall into the lower compartment, where another lactating female with one or two of its own pups are. Of a total of 28 newborn mice of C3H/He and Swiss strains, 23 were successfully fostered. Important observations are presented to show that this is a valuable alternative for foster studies without great suffering on the part of the female.

  2. A Post-Functionalizable Iso-Polyoxotitanate Cage Cluster.

    Science.gov (United States)

    Hou, Jie; Hu, Junyi; Sun, Qing; Zhang, Guanyun; Tung, Chen-Ho; Wang, Yifeng

    2016-07-18

    During solvothermal alcoholysis of a mixture of TiI4 and Ti(O(i)Pr)4, a {I@Ti22} cage cluster encapsulating an OH and iodide guests is crystallized. The {I@Ti22} host-guest cluster surface is postfunctionalizable with catecholate and carboxylate ligands. The synthetic details, structural characterization, spectroscopic properties of the obtained cages clusters are provided. The present study provides candidates for modeling ligand exchange and electron-hole transfer at the titanate nanoparticle surface, and meanwhile offers new opportunities for understanding the TiO2 nanocrystalline formation in solvothermal processes.

  3. Equivalence Between Squirrel Cage and Sheet Rotor Induction Motor

    Science.gov (United States)

    Dwivedi, Ankita; Singh, S. K.; Srivastava, R. K.

    2016-06-01

    Due to topological changes in dual stator induction motor and high cost of its fabrication, it is convenient to replace the squirrel cage rotor with a composite sheet rotor. For an experimental machine, the inner and outer stator stampings are normally available whereas the procurement of rotor stampings is quite cumbersome and is not always cost effective. In this paper, the equivalence between sheet/solid rotor induction motor and squirrel cage induction motor has been investigated using layer theory of electrical machines, so as to enable one to utilize sheet/solid rotor in dual port experimental machines.

  4. Numerical Simulation of Hydrodynamic Behaviors of Gravity Cage in Waves

    Institute of Scientific and Technical Information of China (English)

    ZHAO Yun-peng; LI Yu-cheng; DONG Guo-hai; GUI Fu-kun

    2007-01-01

    This paper aims at investigation of the dynamic properties of gravity cage exposed to waves by use of a numerical model. The numerical model is developed, based on lumped mass method to set up the equations of motion of the whole cage; meanwhile the solutions of equations are solved by the Runge-Kutta-Verner fifth-order and sixth-order method. Physical model tests have been carried out to examine the validity of the numerical model. The results by the numerical simulation agree well with the experimental data.

  5. Mice Do Not Habituate to Metabolism Cage Housing

    DEFF Research Database (Denmark)

    Kalliokoski, Otto; Jacobsen, Kirsten Rosenmaj; Darusman, Huda Shalahudin;

    2013-01-01

    state of the mice also indicated impaired well-being in the metabolism cage housed mice. However, monitoring body weight and feed intake was found misleading in assessing the wellbeing of mice over a longer time course, and the forced swim test was found poorly suited for studying chronic stress in mice...... of abnormality were monitored. Forced swim tests were conducted to determine whether the animals experienced behavioral despair and the serotonergic integrity was tested using an 8-OH-DPAT challenge. The metabolism cage housed mice excreted approximately tenfold higher amounts of corticosterone metabolites...

  6. Quantum collision states for positive charges in an octahedral cage

    CERN Document Server

    Mendes, R V

    2003-01-01

    One-electron energy levels are studied for a configuration of two positive charges inside an octahedral cage, the vertices of the cage being occupied by atoms with a partially filled shell. Although ground states correspond to large separations, there are relatively low-lying states with large collision probabilities. Electromagnetic radiation fields used to excite the quantum collisional levels may provide a means to control nuclear reactions. However, given the scale of the excitation energies involved, this mechanism cannot provide an explanation for the unexplained ``cold fusion'' events.

  7. Caged DNA does not aggregate in high ionic strength solutions.

    Science.gov (United States)

    Trubetskoy, V S; Loomis, A; Slattum, P M; Hagstrom, J E; Budker, V G; Wolff, J A

    1999-01-01

    The assembly of DNA into compact particles that do not aggregate in physiologic salt solution occurs naturally in chromatin and viral particles but has been challenging to duplicate using artificial constructs. Cross-linking amino-containing polycations in the presence of DNA with bisimidoester cross-linker leads to the formation of caged DNA particles that are stable in salt solutions. This first demonstration of caged DNA provides insight into how natural condensation processes avoid aggregation and a promising avenue for developing nonviral gene therapy vectors.

  8. Bulk-Fill Resin Composites

    DEFF Research Database (Denmark)

    Benetti, Ana Raquel; Havndrup-Pedersen, Cæcilie; Honoré, Daniel;

    2015-01-01

    the restorative procedure. The aim of this study, therefore, was to compare the depth of cure, polymerization contraction, and gap formation in bulk-fill resin composites with those of a conventional resin composite. To achieve this, the depth of cure was assessed in accordance with the International Organization...... for Standardization 4049 standard, and the polymerization contraction was determined using the bonded-disc method. The gap formation was measured at the dentin margin of Class II cavities. Five bulk-fill resin composites were investigated: two high-viscosity (Tetric EvoCeram Bulk Fill, SonicFill) and three low......-viscosity (x-tra base, Venus Bulk Fill, SDR) materials. Compared with the conventional resin composite, the high-viscosity bulk-fill materials exhibited only a small increase (but significant for Tetric EvoCeram Bulk Fill) in depth of cure and polymerization contraction, whereas the low-viscosity bulk...

  9. The Incredible Bulk

    CERN Document Server

    Fukushima, Keita; Kumar, Jason; Sandick, Pearl; Yamamoto, Takahiro

    2014-01-01

    Recent experimental results from the LHC have placed strong constraints on the masses of colored superpartners. The MSSM parameter space is also constrained by the measurement of the Higgs boson mass, and the requirement that the relic density of lightest neutralinos be consistent with observations. Although large regions of the MSSM parameter space can be excluded by these combined bounds, leptophilic versions of the MSSM can survive these constraints. In this paper we consider a scenario in which the requirements of minimal flavor violation, vanishing $CP$-violation, and mass universality are relaxed, specifically focusing on scenarios with light sleptons. We find a large region of parameter space, analogous to the original bulk region, for which the lightest neutralino is a thermal relic with an abundance consistent with that of dark matter. We find that these leptophilic models are constrained by measurements of the magnetic and electric dipole moments of the electron and muon, and that these models have ...

  10. Creating bulk nanocrystalline metal.

    Energy Technology Data Exchange (ETDEWEB)

    Fredenburg, D. Anthony (Georgia Institute of Technology, Atlanta, GA); Saldana, Christopher J. (Purdue University, West Lafayette, IN); Gill, David D.; Hall, Aaron Christopher; Roemer, Timothy John (Ktech Corporation, Albuquerque, NM); Vogler, Tracy John; Yang, Pin

    2008-10-01

    Nanocrystalline and nanostructured materials offer unique microstructure-dependent properties that are superior to coarse-grained materials. These materials have been shown to have very high hardness, strength, and wear resistance. However, most current methods of producing nanostructured materials in weapons-relevant materials create powdered metal that must be consolidated into bulk form to be useful. Conventional consolidation methods are not appropriate due to the need to maintain the nanocrystalline structure. This research investigated new ways of creating nanocrystalline material, new methods of consolidating nanocrystalline material, and an analysis of these different methods of creation and consolidation to evaluate their applicability to mesoscale weapons applications where part features are often under 100 {micro}m wide and the material's microstructure must be very small to give homogeneous properties across the feature.

  11. Explosive bulk charge

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Jacob Lee

    2015-04-21

    An explosive bulk charge, including: a first contact surface configured to be selectively disposed substantially adjacent to a structure or material; a second end surface configured to selectively receive a detonator; and a curvilinear side surface joining the first contact surface and the second end surface. The first contact surface, the second end surface, and the curvilinear side surface form a bi-truncated hemispherical structure. The first contact surface, the second end surface, and the curvilinear side surface are formed from an explosive material. Optionally, the first contact surface and the second end surface each have a substantially circular shape. Optionally, the first contact surface and the second end surface consist of planar structures that are aligned substantially parallel or slightly tilted with respect to one another. The curvilinear side surface has one of a smooth curved geometry, an elliptical geometry, and a parabolic geometry.

  12. 48 CFR 204.7204 - Maintenance of the CAGE file.

    Science.gov (United States)

    2010-10-01

    ...) Submit requests for changes to CAGE files on DD Form 2051, or electronic equivalent, to—Defense Logistics.... Telephone Numbers: toll-free (888) 352-9333, DSN 932-4725, commercial (616) 961-4725. Facsimile: (616) 961... contracting and contract administration office receiving notification of changes from the commercial...

  13. Assessment of the Usability of the Workbench Faraday Cage Method

    DEFF Research Database (Denmark)

    Sørensen, Morten; Franek, Ondrej; Christensen, Søren K.

    2011-01-01

    The workbench Faraday Cage method (WBFC) is a time efficient module pre-compliance test regarding radiated emission. This work investigates the method’s usability and credibility and concludes that for this particular case the WBFC perform a tolerable compliance test for frequencies below 360 MHz...

  14. Environmental Impact of Cage Culture on Poondi Reservoir, Tamil Nadu

    Directory of Open Access Journals (Sweden)

    P. Anusuya Devi

    2015-12-01

    Full Text Available The present investigation was carried out in Poondi reservoir, Tamil Nadu, for a period of 8 months from September, 2014 to April, 2015 where the cage culture has been already initiated by the state fisheries department. The water and sediment samples were collected from the reservoir at point and non- point sources of the cage culture units and were analyzed for their physico-chemical parameters. The total microbial load, E. coli and feacal streptococci population were also assessed from the reservoir. During the study period, pH, sulphate, nitrate and BOD values were found within the permissible range for drinking water quality. The alkalinity values were found optimum in the reservoir water. The sediment characteristics such as pH, electrical conductivity, total organic carbon and available phosphorus values were also found to be within the standard limit. The optimum water and sediment quality characteristics and the absence of E. coli and feacal streptococci observed in the cage culture unit clearly showed that the small cage farming in the reservoir does not have major environmental impacts on the water and sediment quality.

  15. EFFECTS OF CAGING DENSITY ON PITUITARY AND TESTICLE RELATED RESPONSES

    Science.gov (United States)

    Effects of caging density on pituitary and testicle related responses A significant negative correlation between the incidence of testicular interstitial cell tumors (ICT) and of pituitary tumors (PT) in control male F344 rats is reported associated with the number of ani...

  16. Massive acetabular bone loss: Limits of trabecular metal cages

    Directory of Open Access Journals (Sweden)

    Villanueva-Martínez Manuel

    2011-01-01

    Full Text Available Massive acetabular bone loss (more than 50% of the acetabular area can result in insufficient native bone for stable fixation and long-term bone ingrowth of conventional porous cups. The development of trabecular metal cages with osteoconductive properties may allow a more biological and versatile approach that will help restore bone loss, thus reducing the frequency of implant failure in the short-to-medium term. We report a case of massive bone loss affecting the dome of the acetabulum and the ilium, which was treated with a trabecular metal cage and particulate allograft. Although the trabecular metal components had no intrinsic stability, they did enhance osseointegration and incorporation of a non-impacted particulate graft, thus preventing failure of the reconstruction. The minimum 50% contact area between the native bone and the cup required for osseointegration with the use of porous cups may not hold for new trabecular metal cups, thus reducing the need for antiprotrusio cages. The osteoconductive properties of trabecular metal enhanced allograft incorportation and iliac bone rebuilding without the need to fill the defect with multiple wedges nor protect the reconstruction with an antiprotrusio cage.

  17. Dynamics of caged ions in glassy ionic conductors.

    Science.gov (United States)

    Habasaki, J; Ngai, K L; Hiwatari, Y

    2004-05-01

    At sufficiently high frequency and low temperature, the dielectric responses of glassy, crystalline, and molten ionic conductors all invariably exhibit nearly constant loss. This ubiquitous characteristic occurs in the short-time regime when the ions are still caged, indicating that it could be a determining factor of the mobility of the ions in conduction at longer times. An improved understanding of its origin should benefit the research of ion conducting materials for portable energy source as well as the resolution of the fundamental problem of the dynamics of ions. We perform molecular dynamics simulations of glassy lithium metasilicate (Li2SiO3) and find that the length scales of the caged Li+ ions motions are distributed according to a Levy distribution that has a long tail. These results suggest that the nearly constant loss originates from "dynamic anharmonicity" experienced by the moving but caged Li+ ions and provided by the surrounding matrix atoms executing correlated movements. The results pave the way for rigorous treatments of caged ion dynamics by nonlinear Hamiltonian dynamics.

  18. Multiexpandable cage for minimally invasive posterior lumbar interbody fusion

    Directory of Open Access Journals (Sweden)

    Coe JD

    2016-09-01

    Full Text Available Jeffrey D Coe,1 James F Zucherman,2 Donald W Kucharzyk,3 Kornelis A Poelstra,4 Larry E Miller,5 Sandeep Kunwar,6 1Silicon Valley Spine Institute, Campbell, 2San Francisco Orthopaedic Surgeons, San Francisco, CA, 3Orthopaedic Pediatric and Spine, Crown Point, IN, 4Department of Surgery, Sacred Heart Hospital on the Emerald Coast, Miramar Beach, FL, 5Miller Scientific Consulting, Inc., Asheville, NC, 6Bell Neuroscience Institute, Washington Hospital Healthcare System, Fremont, CA, USA Abstract: The increasing adoption of minimally invasive techniques for spine surgery in recent years has led to significant advancements in instrumentation for lumbar interbody fusion. Percutaneous pedicle screw fixation is now a mature technology, but the role of expandable cages is still evolving. The capability to deliver a multiexpandable interbody cage with a large footprint through a narrow surgical cannula represents a significant advancement in spinal surgery technology. The purpose of this report is to describe a multiexpandable lumbar interbody fusion cage, including implant characteristics, intended use, surgical technique, preclinical testing, and early clinical experience. Results to date suggest that the multiexpandable cage allows a less invasive approach to posterior/transforaminal lumbar interbody fusion surgery by minimizing iatrogenic risks associated with static or vertically expanding interbody prostheses while providing immediate vertebral height restoration, restoration of anatomic alignment, and excellent early-term clinical results. Keywords: degenerative disc disease, expandable, low back pain, Luna

  19. Three-dimensional protonic conductivity in porous organic cage solids

    Science.gov (United States)

    Liu, Ming; Chen, Linjiang; Lewis, Scott; Chong, Samantha Y.; Little, Marc A.; Hasell, Tom; Aldous, Iain M.; Brown, Craig M.; Smith, Martin W.; Morrison, Carole A.; Hardwick, Laurence J.; Cooper, Andrew I.

    2016-09-01

    Proton conduction is a fundamental process in biology and in devices such as proton exchange membrane fuel cells. To maximize proton conduction, three-dimensional conduction pathways are preferred over one-dimensional pathways, which prevent conduction in two dimensions. Many crystalline porous solids to date show one-dimensional proton conduction. Here we report porous molecular cages with proton conductivities (up to 10-3 S cm-1 at high relative humidity) that compete with extended metal-organic frameworks. The structure of the organic cage imposes a conduction pathway that is necessarily three-dimensional. The cage molecules also promote proton transfer by confining the water molecules while being sufficiently flexible to allow hydrogen bond reorganization. The proton conduction is explained at the molecular level through a combination of proton conductivity measurements, crystallography, molecular simulations and quasi-elastic neutron scattering. These results provide a starting point for high-temperature, anhydrous proton conductors through inclusion of guests other than water in the cage pores.

  20. Business plan Tilapia cage farming in Tete Zambezi Valley, Mozambique

    NARCIS (Netherlands)

    Meer, van der Magnus; Brouwer, Herman

    2015-01-01

    Tete province offers great opportunities for cage farming of tilapia in Lake Cahora Bassa. The climate and water quality are favourable for fish production, and the fast economic developments in the region will facilitate fish sales. In Tete tilapia (pende) is highly valued food. Major markets for t

  1. Sex effect in mutual olfactory relationships of individually caged rabbits

    Directory of Open Access Journals (Sweden)

    Alessandro Finzi

    2015-12-01

    Full Text Available To assess the sex influence on sniffing behavior of rabbits, sets of three rabbits each were located for seven days in contiguous cages divided by a metal wall with holes that prevented the neighboring rabbits to see each other. A buck was located in the central cage, with a doe at each side. Rabbit behavior was video recorded to observe animals sniffing with the muzzle near the wall. The bucks displayed an olfactory preference towards one of the two does, which decreased in few days. The significance was p  0.05. The interest of bucks towards the does was also characterized by a frenetic scratching of the separation wall, contemporary with intense sniffing, displayed only for the first 35 min of the first day. The sniffing behavior of does at the central cage housing the male was not so marked as in bucks, and it progressively changed across the trial (p < 0.01. In conclusion, rabbits establish a transitory sex-oriented olfactory relationship with the conspecifics housed in contiguous cages, which looks no longer necessary once the rabbits have recognized each other.

  2. Three-dimensional protonic conductivity in porous organic cage solids

    Science.gov (United States)

    Liu, Ming; Chen, Linjiang; Lewis, Scott; Chong, Samantha Y.; Little, Marc A.; Hasell, Tom; Aldous, Iain M.; Brown, Craig M.; Smith, Martin W.; Morrison, Carole A.; Hardwick, Laurence J.; Cooper, Andrew I.

    2016-01-01

    Proton conduction is a fundamental process in biology and in devices such as proton exchange membrane fuel cells. To maximize proton conduction, three-dimensional conduction pathways are preferred over one-dimensional pathways, which prevent conduction in two dimensions. Many crystalline porous solids to date show one-dimensional proton conduction. Here we report porous molecular cages with proton conductivities (up to 10−3 S cm−1 at high relative humidity) that compete with extended metal-organic frameworks. The structure of the organic cage imposes a conduction pathway that is necessarily three-dimensional. The cage molecules also promote proton transfer by confining the water molecules while being sufficiently flexible to allow hydrogen bond reorganization. The proton conduction is explained at the molecular level through a combination of proton conductivity measurements, crystallography, molecular simulations and quasi-elastic neutron scattering. These results provide a starting point for high-temperature, anhydrous proton conductors through inclusion of guests other than water in the cage pores. PMID:27619230

  3. The biological effect of cage design corrected for reductions in spray penetration

    OpenAIRE

    Fritz Bradley Keith; Hoffmann Wesley Clint; Bonds Jane Annalise Sara; Haas Keith; Czaczyk Zbigniew

    2014-01-01

    In-field measures of physical spray concentration do not tend to correlate well with caged insect mortality data. This is partly due to the reduced penetration of the spray into the cage. Spray penetration is hindered by the structure of the cage. Wind tunnel studies were conducted to investigate the accuracy of those calculations developed to correct for filtration levels in caged mosquito bioassays. Zenivex E20 (Etofenprox) was applied at rates ranging from an LD10 to an LD90. Thre...

  4. Mouse Housing System Using Pressurized Cages Intraventilated by Direct-Current Microfans

    OpenAIRE

    Martinewski, Alexandre; Correia, Caio SC; de Souza, Nívea L; Merusse, José LB

    2012-01-01

    We performed the initial assessment of an alternative pressurized intraventilated (PIV) caging system for laboratory mice that uses direct-current microfans to achieve cage pressurization and ventilation. Twenty-nine pairs of female SPF BALB/c mice were used, with 19 experimental pairs kept in PIV cages and 10 control pairs kept in regular filter-top (FT) cages. Both groups were housed in a standard housing room with a conventional atmospheric control system. For both systems, intracage tempe...

  5. Laser Induced C60 Cage Opening Studied by Semiclassical Dynamics Simulation

    Directory of Open Access Journals (Sweden)

    Yusheng Dou

    2011-01-01

    Full Text Available Laser induced opening of the C60 cage is studied by a semiclassical electron-radiation-ion dynamics technique. The simulation results indicate that the C60 cage is abruptly opened immediately after laser excitation. The opening of the C60 cage induces a quick increase in kinetic energy and a sharp decrease in electronic energy, suggesting that the breaking of the C60 cage efficiently heats up the cluster and enhances the thermal fragmentation of C60 fullerene.

  6. Social communication in mice--are there optimal cage conditions?

    Directory of Open Access Journals (Sweden)

    Allain-Thibeault Ferhat

    Full Text Available Social communication is heavily affected in patients with neuropsychiatric disorders. Accordingly, mouse models designed to study the mechanisms leading to these disorders are tested for this phenotypic trait. Test conditions vary between different models, and the effect of these test conditions on the quantity and quality of social interactions and ultrasonic communication is unknown. The present study examines to which extent the habituation time to the test cage as well as the shape/size of the cage influence social communication in freely interacting mice. We tested 8 pairs of male mice in free dyadic social interactions, with two habituation times (20 min and 30 min and three cage formats (rectangle, round, square. We tested the effect of these conditions on the different types of social contacts, approach-escape sequences, follow behavior, and the time each animal spent in the vision field of the other one, as well as on the emission of ultrasonic vocalizations and their contexts of emission. We provide for the first time an integrated analysis of the social interaction behavior and ultrasonic vocalizations. Surprisingly, we did not highlight any significant effect of habituation time and cage shape/size on the behavioral events examined. There was only a slight increase of social interactions with the longer habituation time in the round cage. Remarkably, we also showed that vocalizations were emitted during specific behavioral sequences especially during close contact or approach behaviors. The present study provides a protocol reliably eliciting social contacts and ultrasonic vocalizations in adult male mice. This protocol is therefore well adapted for standardized investigation of social interactions in mouse models of neuropsychiatric disorders.

  7. Cage Versus Noncage Laying-Hen Housings: Worker Respiratory Health.

    Science.gov (United States)

    Mitchell, Diane; Arteaga, Veronica; Armitage, Tracey; Mitloehner, Frank; Tancredi, Daniel; Kenyon, Nicholas; Schenker, Marc

    2015-01-01

    The objective of this study was to compare respiratory health of poultry workers in conventional cage, enriched cage and aviary layer housing on a single commercial facility, motivated by changing requirements for humane housing of hens. Three workers were randomly assigned daily, one to each of conventional cage, enriched cage, and aviary housing in a crossover repeated-measures design for three observation periods (for a total of 123 worker-days, eight different workers). Workers' exposure to particles were assessed (Arteaga et al. J Agromedicine. 2015;20:this issue) and spirometry, exhaled nitric oxide, respiratory symptoms, and questionnaires were conducted pre- and post-shift. Personal exposures to particles and endotoxin were significantly higher in the aviary than the other housings (Arteaga et al., 2015). The use of respiratory protection was high; the median usage was 70% of the shift. Mixed-effects multivariate regression models of respiratory cross-shift changes were marginally significant, but the aviary system consistently posted the highest decrements for forced expiratory volume in 1 and 6 seconds (FEV1 and FEV6) compared with the enriched or conventional housing. The adjusted mean difference in FEV1 aviary - enriched cage housing was -47 mL/s, 95% confidence interval (CI): (-99 to 4.9), P = .07. Similarly, for FEV6, aviary - conventional housing adjusted mean difference was -52.9 mL/6 s, 95% CI: (-108 to 2.4), P = .06. Workers adopting greater than median use of respiratory protection were less likely to exhibit negative cross-shift pulmonary function changes. Although aviary housing exposed workers to significantly higher respiratory exposures, cross-shift pulmonary function changes did not differ significantly between houses. Higher levels of mask use were protective; poultry workers should wear respiratory protection as appropriate to avoid health decrements.

  8. The effects of climbing cages on behaviour of female mink during the lactation period

    DEFF Research Database (Denmark)

    Lidfors, L.; Axelsson, H.; Loberg, J.;

    2012-01-01

    The aim was to investigate if there were differences in behaviour of female mink when kept in a climbing cage compared with a standard cage during the lactation period. The study was carried out on 90 mink of the colour type "black cross". Females were housed in either climbing cages (4.350 cm², n...

  9. 48 CFR 252.204-7001 - Commercial and Government Entity (CAGE) code reporting.

    Science.gov (United States)

    2010-10-01

    ... Entity (CAGE) code reporting. 252.204-7001 Section 252.204-7001 Federal Acquisition Regulations System... Entity (CAGE) Code Reporting (AUG 1999) (a) The offeror is requested to enter its CAGE code on its offer... AND CONTRACT CLAUSES Text of Provisions And Clauses 252.204-7001 Commercial and Government...

  10. Rotational Brownian Dynamics simulations of clathrin cage formation

    Energy Technology Data Exchange (ETDEWEB)

    Ilie, Ioana M.; Briels, Wim J. [Computational BioPhysics, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede (Netherlands); MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede (Netherlands); Otter, Wouter K. den, E-mail: w.k.denotter@utwente.nl [Computational BioPhysics, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede (Netherlands); MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede (Netherlands); Multi Scale Mechanics, Faculty of Engineering Technology, University of Twente, P.O. Box 217, 7500 AE Enschede (Netherlands)

    2014-08-14

    The self-assembly of nearly rigid proteins into ordered aggregates is well suited for modeling by the patchy particle approach. Patchy particles are traditionally simulated using Monte Carlo methods, to study the phase diagram, while Brownian Dynamics simulations would reveal insights into the assembly dynamics. However, Brownian Dynamics of rotating anisotropic particles gives rise to a number of complications not encountered in translational Brownian Dynamics. We thoroughly test the Rotational Brownian Dynamics scheme proposed by Naess and Elsgaeter [Macromol. Theory Simul. 13, 419 (2004); Naess and Elsgaeter Macromol. Theory Simul. 14, 300 (2005)], confirming its validity. We then apply the algorithm to simulate a patchy particle model of clathrin, a three-legged protein involved in vesicle production from lipid membranes during endocytosis. Using this algorithm we recover time scales for cage assembly comparable to those from experiments. We also briefly discuss the undulatory dynamics of the polyhedral cage.

  11. Mutual Inductance in the Bird-Cage Resonator

    Science.gov (United States)

    Tropp, James

    1997-05-01

    Formulas are derived to account for the effect of the mutual inductances, between all meshes, upon the electrical resonance spectra bird-cage resonators, and similar structures such as the TEM resonator of P. K. H. Röschmann (United States Patent 4,746,866) and J. T. Vaughanet al.(Magn. Reson. Med.32,206, 1994). The equations are parameterized in terms of isolated mesh frequencies and coupling coefficients, and ought therefore apply not only to simple magnetic couplings used in the derivation, but to electromagnetic couplings as well. A method for measuring the coupling coefficients-applicable to shielded as well as unshielded resonators-is described, based upon the splitting of frequencies in pairs of coupled resonators; and detailed comparisons are given between calculated and measured resonance spectra: for bird-cage resonators, with and without shields, and for the TEM resonator.

  12. Macromolecularly "Caged" Carbon Nanoparticles for Intracellular Trafficking via Switchable Photoluminescence.

    Science.gov (United States)

    Misra, Santosh K; Srivastava, Indrajit; Tripathi, Indu; Daza, Enrique; Ostadhossein, Fatemeh; Pan, Dipanjan

    2017-02-08

    Reversible switching of photoluminescence (PL) of carbon nanoparticles (CNP) can be achieved with counterionic macromolecular caging and decaging at the nanoscale. A negatively charged uncoated, "bare" CNP with high luminescence loses its PL when positively charged macromolecules are wrapped around its surface. Prepared caged carbons could regain their emission only through interaction with anionic surfactant molecules, representing anionic amphiphiles of endocytic membranes. This process could be verified by gel electrophoresis, spectroscopically and in vitro confocal imaging studies. Results indicated for the first time that luminescence switchable CNPs can be synthesized for efficient intracellular tracking. This study further supports the origin of photoluminescence in CNP as a surface phenomenon correlated a function of characteristic charged macromolecules.

  13. Lanthanides caged by the organic chelates; structural properties.

    Science.gov (United States)

    Smentek, Lidia

    2011-04-13

    The structure, in particular symmetry, geometry and morphology of organic chelates coordinated with the lanthanide ions are analyzed in the present review. This is the first part of a complete presentation of a theoretical description of the properties of systems, which are widely used in technology, but most of all, in molecular biology and medicine. The discussion is focused on the symmetry and geometry of the cages, since these features play a dominant role in the spectroscopic activity of the lanthanides caged by organic chelates. At the same time, the spectroscopic properties require more formal presentation in the language of Racah algebra, and deserve a separate analysis. In addition to the parent systems of DOTA, DOTP, EDTMP and CDTMP presented here, their modifications by various antennas are analyzed. The conclusions that have a strong impact upon the theory of the energy transfer and the sensitized luminescence of these systems are based on the results of numerical density functional theory calculations.

  14. Rotational Brownian dynamics simulations of clathrin cage formation.

    Science.gov (United States)

    Ilie, Ioana M; den Otter, Wouter K; Briels, Wim J

    2014-08-14

    The self-assembly of nearly rigid proteins into ordered aggregates is well suited for modeling by the patchy particle approach. Patchy particles are traditionally simulated using Monte Carlo methods, to study the phase diagram, while Brownian Dynamics simulations would reveal insights into the assembly dynamics. However, Brownian Dynamics of rotating anisotropic particles gives rise to a number of complications not encountered in translational Brownian Dynamics. We thoroughly test the Rotational Brownian Dynamics scheme proposed by Naess and Elsgaeter [Macromol. Theory Simul. 13, 419 (2004); Naess and Elsgaeter Macromol. Theory Simul. 14, 300 (2005)], confirming its validity. We then apply the algorithm to simulate a patchy particle model of clathrin, a three-legged protein involved in vesicle production from lipid membranes during endocytosis. Using this algorithm we recover time scales for cage assembly comparable to those from experiments. We also briefly discuss the undulatory dynamics of the polyhedral cage.

  15. Mutual Inductance in the Bird-Cage Resonator

    Science.gov (United States)

    Tropp

    1997-05-01

    Formulas are derived to account for the effect of the mutual inductances, between all meshes, upon the electrical resonance spectra bird-cage resonators, and similar structures such as the TEM resonator of P. K. H. Roschmann (United States Patent 4,746,866) and J. T. Vaughan et al. (Magn. Reson. Med. 32, 206, 1994). The equations are parameterized in terms of isolated mesh frequencies and coupling coefficients, and ought therefore apply not only to simple magnetic couplings used in the derivation, but to electromagnetic couplings as well. A method for measuring the coupling coefficients-applicable to shielded as well as unshielded resonators-is described, based upon the splitting of frequencies in pairs of coupled resonators; and detailed comparisons are given between calculated and measured resonance spectra: for bird-cage resonators, with and without shields, and for the TEM resonator.

  16. Can bulk viscosity drive inflation

    Energy Technology Data Exchange (ETDEWEB)

    Pacher, T.; Stein-Schabes, J.A.; Turner, M.S.

    1987-09-15

    Contrary to other claims, we argue that bulk viscosity associated with the interactions of non- relativistic particles with relativistic particles around the time of the grand unified theory (GUT) phase transition cannot lead to inflation. Simply put, the key ingredient for inflation, negative pressure, cannot arise due to the bulk-viscosity effects of a weakly interacting mixture of relativistic and nonrelativistic particles.

  17. Brane Couplings from Bulk Loops

    OpenAIRE

    Georgi, Howard; Grant, Aaron K.; Hailu, Girma

    2000-01-01

    We compute loop corrections to the effective action of a field theory on a five-dimensional $S_1/Z_2$ orbifold. We find that the quantum loop effects of interactions in the bulk produce infinite contributions that require renormalization by four-dimensional couplings on the orbifold fixed planes. Thus bulk couplings give rise to renormalization group running of brane couplings.

  18. Early access to perches in caged White Leghorn pullets.

    Science.gov (United States)

    Enneking, S A; Cheng, H W; Jefferson-Moore, K Y; Einstein, M E; Rubin, D A; Hester, P Y

    2012-09-01

    Osteoporosis, a progressive decrease in mineralized structural bone, causes 20 to 35% of all mortalities in caged White Leghorn hens. Previous research has focused on manipulating the egg laying environment to improve skeletal health, with little research on the pullet. The objective of the current study was to determine the effect of perch access on pullet health, bone mineralization, muscle deposition, and stress in caged White Leghorns. From 0 to 17 wk of age, half of the birds were placed in cages with 2 round metal perches, while the other half did not have perches (controls). Bone mineralization and bone size traits were determined in the tibia, femur, sternum, humerus, ulna, radius, and phalange (III carpometacarpal) using dual energy x-ray absorptiometry. Muscle weights were obtained for the breast and left leg (drum and thigh). A sample of pullets from each cage was evaluated for foot health, BW, right adrenal weight, and packed cell volume. Most measurements were taken at 3, 6, and 12 wk of age. Access to perches did not affect breast muscle weight, percentage breast muscle, percentage leg muscle, bone mineral density, bone length, bone width, adrenal weight, packed cell volume, and hyperkeratosis of the foot-pad and toes. There were no differences in BW, bone mineral content, and leg muscle weight at 3 and 6 wk of age. However, at 12 wk of age, BW (P = 0.025), bone mineral content of the tibia, sternum, and humerus (P = 0.015), and the left leg muscle weight (P = 0.006) increased in pullets with access to perches as compared with controls. These results suggest that perch access has beneficial effects on pullet health by stimulating leg muscle deposition and increasing the mineral content of certain bones without causing a concomitant decrease in bone mineral density.

  19. Inherent helicity in an extended tris-bipyridyl molecular cage

    Energy Technology Data Exchange (ETDEWEB)

    Perkins, D.; Lindoy, L.; Meehan, G.; Turner, P. (University of Sydney)

    2010-11-16

    A new molecular cage incorporating three bipyridyl units has been synthesised by a conventional multi-step procedure as well as, much more efficiently, by a Ni(II) template procedure; an X-ray structure of the nickel complex shows that it adopts an exo configuration of each of the bridgehead nitrogen lone pairs, the central metal ion acts to promote a triple helical twist that extends {approx}22 {angstrom} along the axial length of the molecule.

  20. Crop impaction resulting from feather ball formation in caged layers.

    Science.gov (United States)

    Morishita, T Y; Aye, P P; Harr, B S

    1999-01-01

    Abnormal behaviors in commercial poultry, including feather pulling and pica, have been known to occur when birds are exposed to an unfamiliar environment. We report here the development of crop impactions resulting from feather ball formation. Twelve specific-pathogen-free (SPF) chickens were placed in one of three cages housed among a commercial layer flock in three different buildings on a farm site. Three weeks after placement, the birds were removed from the cages and given a physical exam. Chickens were thin, and one bird in each of the three caged groups had a palpable mass at the level of the thoracic inlet. At necropsy, a mass was noted in the crop. Upon further dissection, a wet, foul-smelling mass consisting of feathers and feed debris was recovered. Results from our case indicate that unfamiliar surroundings can cause pica in birds. Hence, avian researchers and veterinarians planning to introduce new birds into a flock, i.e., SPF birds, should consider the birds' previous environmental conditions prior to placement because sudden placement in unfamiliar surroundings can result in pica.

  1. Structure and energetic characteristics of methane hydrates. From single cage to triple cage: A DFT-D study

    Science.gov (United States)

    Giricheva, N. I.; Ischenko, A. A.; Yusupov, V. I.; Bagratashvili, V. N.; Girichev, G. V.

    2017-03-01

    Electronic, geometrical, vibrational and energetic characteristics of the ice I TDT fragment consisted of dodecahedron H2O[512] (D) fused with two tetrakaidecahedrons H2O[51262] (T) and of the TDT cluster with three encapsulated CH4 molecules (3CH4·TDT) were calculated using a DFT/B97-D/6-311++G(2d,2p) approach. Binding energies, hydrogen bonding energies, energies of encapsulation of methane molecules into small D- and large T-cages of the TDT fragment, energies of frontier orbitals, the translational and librational frequencies, as well as the intramolecular vibrations of methane within the cages of different sizes were studied. Similar characteristics of isolated D- and T-cages and clathrates CH4·D and CH4·T were studied as function of compression/expansion of their oxygen skeletons using DFT/B97-D, LC-B3LYP, B3LYP-D2 methods.

  2. Flow Field Characteristics of the Rotor Cage in Turbo Air Classifiers

    Institute of Scientific and Technical Information of China (English)

    GUO Lijie; LIU Jiaxiang; LIU Shengzhao

    2009-01-01

    The turbo air classifier is widely used powder classification equipment in a variety of fields. The flow field characteristics of the turbo air classifier are important basis for the improvement of the turbo air classifier's structural design. The flow field characteristics of the rotor cage in turbo air classifiers were investigated under different operating conditions by laser Doppler velocimeter(LDV), and a measure diminishing the axial velocity is proposed. The investigation results show that the tangential velocity of the air flow inside the rotor cage is different from the rotary speed of the rotor cage on the same measurement point due to the influences of both the negative pressure at the exit and the rotation of the rotor cage. The tangential velocity of the air flow likewise decreases as the radius decreases in the case of the rotor cage's low rotary speed. In contrast, the tangential velocity of the air flow increases as the radius decreases in the case of the rotor cage's high rotary speed. Meanwhile, the vortex inside the rotor cage is found to occur near the pressure side of the blade when the rotor cage's rotary speed is less than the tangential velocity of air flow. On the contrary, the vortex is found to occur near the blade suction side once the rotor cage's rotary speed is higher than the tangential velocity of air flow. Inside the rotor cage, the axial velocity could not be disregarded and is largely determined by the distances between the measurement point and the exit.

  3. Effects of Furnished Cage Type on Behavior and Welfare of Laying Hens.

    Science.gov (United States)

    Li, Xiang; Chen, Donghua; Li, Jianhong; Bao, Jun

    2016-06-01

    This study was conducted to compare the effects of layout of furniture (a perch, nest, and sandbox) in cages on behavior and welfare of hens. Two hundred and sixteen Hyline Brown laying hens were divided into five groups (treatments) with four replicates per group: small furnished cages (SFC), medium furnished cages type I (MFC-I), medium furnished cages type II (MFC-II), and medium furnished cages type III (MFC-III) and conventional cages (CC). The experiment started at 18 week of age and finished at 52 week of age. Hens' behaviors were filmed during the following periods: 8:00 to 10:00; 13:00 to 14:00; 16:00 to 17:00 on three separate days and two hens from each cage were measured for welfare parameters at 50 wk of age. The results showed that feeding and laying of all hens showed no effect by cage type (p>0.05), and the hens in the furnished cages had significantly lower standing and higher walking than CC hens (p0.05). The hens in MFC-I, -II, and -III showed a significant higher socializing behavior than SFC and CC (p<0.05). The lowest perching was for the hens in SFC and the highest perching found for the hens in MFC-III. Overall, the hens in CC showed poorer welfare conditions than the furnished cages, in which the feather condition score, gait score and tonic immobility duration of the hens in CC was significantly higher than SFC, MFC-I, MFC-II, and MFC-III (p<0.05). In conclusion, the furnished cage design affected both behavior and welfare states of hens. Overall, MFC-III cage design was better than SFC, MFC-I, and MFC-II cage designs.

  4. Synthesis of copper and zinc sulfide nanocrystals via thermolysis of the polymetallic thiolate cage

    Directory of Open Access Journals (Sweden)

    Toshihiro Kuzuya, Yutaka Tai, Saeki Yamamuro and Kenji Sumiyama

    2005-01-01

    Full Text Available In this paper report on the synthesis of copper and zinc sulfide nanocrystals (NCs via the formation of polymetallic thiolate cages. Cu2S NCs derived from Cu–dodecanethiol complex formed well-defined spherers, which were sufficiently monodisperse (with a size distribution of ~10% standard deviation of approximately 4.7 nm diameter on average to generate ordered self-assemblies. An electron diffraction pattern and UV–vis spectrum of Cu2S NCs indicate that this process can provide pure β-chalcocite (Cu2S. Nearly monodisperse ZnS NCs with a size ranging from 3 to 7 nm were obtained by thermolysis of the S–Zn–dodecanethiol precursor. The electron diffraction pattern indicates that zinc sulfide NCs are either wurtzite or a mixture of wurtzite and zincblende. TEM observation and UV–vis spectra revealed that the growth rate of ZnS NCs depends strongly on the annealing temperature. UV–vis spectra of 3 nm ZnS NCs show sharp excitonic features and a large blue shift from the bulk material. The photoluminescence spectra exhibit a large red shift from the absorption band edges. These shifts could be attributed to recombination from the surface traps. The narrow size distribution of Cu2S and ZnS NCs led to the formation of ordered self-assemblies with various well-defined but nonclosed-packing.

  5. Supramolecular concepts and new techniques in mechanochemistry: cocrystals, cages, rotaxanes, open metal-organic frameworks.

    Science.gov (United States)

    Friščić, Tomislav

    2012-05-07

    Mechanochemical reactions effected by milling or grinding are an attractive means to conduct chemical reactions dependent on molecular recognition and to systematically explore different modes of molecular self-assembly. The natural relationship between milling mechanochemistry and supramolecular chemistry arises primarily from the ability to avoid bulk solvent, which simultaneously avoids limitations of solution-based chemistry, such as solubility, solvent complexation, or solvolysis, and makes the resulting process highly environmentally friendly. This tutorial review highlights the use of mechanochemistry for the synthesis of supramolecular targets in the solid state, such as molecular hydrogen- or halogen-bonded complexes, molecular and supramolecular cages, open frameworks and interlocked architectures. It is also demonstrated that the molecular self-assembly phenomena that are well-established in solution chemistry, such as reversible binding through covalent or non-covalent bonds, thermodynamic equilibration and structure templating, are also accessible in milling mechanochemistry through recently developed highly efficient methodologies such as liquid-assisted grinding (LAG) or ion- and liquid-assisted grinding (ILAG). Also highlighted are the new opportunities arising from the marriage of concepts of supramolecular and mechanochemical synthesis, including organocatalysis, deracemisation and discovery of new molecular recognition motifs.

  6. Can bulk viscosity drive inflation

    Energy Technology Data Exchange (ETDEWEB)

    Pacher, T.; Stein-Schabes, J.A.; Turner, M.S.

    1987-04-01

    Contrary to other claims, we argue that, bulk viscosity associated with the interactions of nonrelativistic particles with relativistic particles around the time of the grand unified theory (GUT) phase transition cannot lead to inflation. Simply put, the key ingredient for inflation, negative pressure, cannot arise due to the bulk viscosity effects of a weakly-interacting mixture of relativistic and nonrelativistic particles. 13 refs., 1 fig.

  7. Design and performance of a double-tuned bird-cage coil

    Science.gov (United States)

    Rath, Alan R.

    The "high-pass" and "low-pass" designations commonly given to bird-cage coils derive in each case from the relationship of the individual sections of the bird cage to simple filters. By extension of the concept of constructing a bird-cage coil from elementary filter sections, it is possible to create coils which support "bird-cage mode" resonances at more than one frequency. Designs based on both simple bandpass and band-stop filters, for example, provide means to realize bird-cage coils which may be tuned simultaneously to two frequencies. Construction and performance of a band-stop bird cage operating at both 200 and 81 MHz are described.

  8. Design And Development Of Roll Cage For An All-Terrain Vehicle

    Directory of Open Access Journals (Sweden)

    Khelan Chaudhari

    2013-12-01

    Full Text Available The study aims to design, develop and fabricate a roll cage for an All-Terrain Vehicle (ATV in accordance with the rulebook of BAJA 2013 given by SAE. A roll cage is a skeleton of an ATV. The roll cage not only forms the structural base but also a 3-D shell surrounding the occupant which protects the occupant in case of impact and roll over incidents. The roll cage also adds to the aesthetics of a vehicle. The design and development comprises of material selection, chassis and frame design, cross section determination, determining strength requirements of roll cage, stress analysis and simulations to test the ATV against failure. Finally the roll cage is fabricated as per the tools and techniques available in the workshop.

  9. Synthesis and photochemical properties of PEGylated coumarin-caged ceramides for cell studies.

    Science.gov (United States)

    Kim, Young Ah; Day, Jenna; Lirette, Carol Ann; Costain, Willard J; Johnston, Linda J; Bittman, Robert

    2016-01-01

    Caged ceramide analogues (C6-, C16-, C18-, C22- and C24-Cer) have been prepared by introducing a hydrophilic coumarin-based cage bearing a short polyethylene glycol (PEG) chain. (6-Bromo-7-mTEGylated-coumarin-4-yl)methyl (Btc) caged ceramide showed efficient photo-uncaging to release the parent ceramide upon direct exposure to 350 nm UV light; in contrast (7-mTEGylated-coumarin-4-yl)methyl (Tc) caged ceramide was photolysed more slowly. In preliminary experiments, Btc-caged ceramides were taken up by cells and their photolysis led to decreases in cell viability, but not to activation of caspase enzymes, suggesting that either reactive oxygen species or an alternate caspase-independent pathway may be responsible for the decreases in cell viability caused by photolysis of caged ceramides.

  10. Greenhouse Gas Emissions from Three Cage Layer Housing Systems

    Directory of Open Access Journals (Sweden)

    John Feddes

    2011-12-01

    Full Text Available Agriculture accounts for 10 to 12% of the World’s total greenhouse gas (GHG emissions. Manure management alone is responsible for 13% of GHG emissions from the agricultural sector. During the last decade, Québec’s egg production systems have shifted from deep-pit housing systems to manure belt housing systems. The objective of this study was to measure and compare carbon dioxide (CO2, methane (CH4 and nitrous oxide (N2O emissions from three different cage layer housing systems: a deep liquid manure pit and a manure belt with natural or forced air drying. Deep liquid manure pit housing systems consist of “A” frame layer cages located over a closed pit containing the hens’ droppings to which water is added to facilitate removal by pumping. Manure belt techniques imply that manure drops on a belt beneath each row of battery cages where it is either dried naturally or by forced air until it is removed. The experiment was replicated with 360 hens reared into twelve independent bench-scale rooms during eight weeks (19–27 weeks of age. The natural and forced air manure belt systems reduced CO2 (28.2 and 28.7 kg yr−1 hen−1, respectively, CH4 (25.3 and 27.7 g yr−1 hen−1, respectively and N2O (2.60 and 2.48 g yr−1 hen−1, respectively emissions by about 21, 16 and 9% in comparison with the deep-pit technique (36.0 kg CO2 yr−1 hen−1, 31.6 g CH4 yr−1 hen−1 and 2.78 g N2O yr−1 hen−1. The shift to manure belt systems needs to be encouraged since this housing system significantly decreases the production of GHG.

  11. The influence of halides in polyoxotitanate cages; dipole moment, splitting and expansion of d-orbitals and electron-electron repulsion.

    Science.gov (United States)

    Hanf, Schirin; Matthews, Peter D; Li, Ning; Luo, He-Kuan; Wright, Dominic S

    2017-01-03

    Metal-doped polyoxotitanate (M-POT) cages have been shown to be efficient single-source precursors to metal-doped titania [TiO2(M)] (state-of-the-art photocatalytic materials) as well as molecular models for the behaviour of dopant metal ions in bulk titania. Here we report the influence halide ions have on the optical and electronic properties of a series of halide-only, and cobalt halide-'doped' POT cages. In this combined experimental and computational study we show that halide ions can have several effects on the band gaps of halide-containing POT cages, influencing the dipole moment (hole-electron separation) and the structure of the valance band edge. Overall, the band gap behaviour stems from the effects of increasing orbital energy moving from F to I down Group 17, as well as crystal-field splitting of the d-orbitals, the potential effects of the Nephelauxetic influence of the halides and electron-electron repulsion.

  12. Effect of steerable cage placement during minimally invasive transforaminal lumbar interbody fusion on lumbar lordosis.

    Science.gov (United States)

    Lindley, Timothy E; Viljoen, Stephanus V; Dahdaleh, Nader S

    2014-03-01

    Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) is commonly used for the treatment of a variety of degenerative spine disorders. Recently, steerable interbody cages have been developed which potentially allow for greater restoration of lumbar lordosis. Here we describe a technique and radiographic results following minimally invasive placement of steerable cages through a bilateral approach. A retrospective review was conducted of the charts and radiographs of 15 consecutive patients who underwent 19 levels of bilateral MIS-TLIF with the placement of steerable cages. These were compared to 10 patients who underwent 16 levels of unilateral MIS-TLIF with the placement of bullet cages. The average age, body mass index, distribution of the levels operated and follow-up were similar in both groups. The average height of the steerable cage placed was 10.9 mm compared to 8.5mm for bullet cages. The preoperative focal Cobb's angle per level was similar between both groups with a mean of -5.3 degrees for the steerable cage group and -4.8 degrees for the bullet cage group. There was a significant improvement in postoperative Cobb's angle after placement of a steerable cage with a mean of -13.7 (p<0.01) and this persisted at the last follow-up with -13 degrees (p<0.01). There was no significant change in Cobb's angle after bullet cage placement with -5.7 degrees postoperatively and a return to the baseline preoperative Cobb's angle of -4.8 at the last follow-up. Steerable cage placement for MIS-TLIF improves focal lordosis compared to bullet cage placement.

  13. Are assemblages of the fireworm Hermodice carunculata enhanced in sediments beneath offshore fish cages?

    Institute of Scientific and Technical Information of China (English)

    Rodrigo Riera; Oscar Prez; Myriam Rodrguez; Eva Ramos; scar Monterroso

    2014-01-01

    Abundances of the fireworm Hermodice carunculata were counted through a monitoring assessment study of fish cages in Barranco Hondo (NE Tenerife). Seven campaigns were conducted from November 2007 to June 2010 and temporal variations were found, as well as differences among sampling stations. The poly-chaete H. carunculata obtained its highest abundance in sediments beneath fish cages throughout the study period. Thus, the assemblages of this omnivorous species were favoured by the presence of fish cages.

  14. Shape assisted fabrication of fluorescent cages of squarate based metal-organic coordination frameworks.

    Science.gov (United States)

    Jayaramulu, Kolleboyina; Krishna, Katla Sai; George, Subi J; Eswaramoorthy, Muthuswamy; Maji, Tapas Kumar

    2013-05-11

    Micronic cage structures of squarate based metal-organic coordination frameworks (MOCFs) have been fabricated for the first time by specific anion selective etching of metal squarate cubes. Time and stoichiometry dependent synthesis and the corresponding microscopic studies have provided mechanistic insight into the cage formation. Furthermore, a non-covalent post-synthetic strategy has been adopted to functionalize the micronic cubes or cages with chromophores rendering the resulting hybrids green fluorescent.

  15. Regioselective nitration of aromatic substrates in zeolite cages

    Indian Academy of Sciences (India)

    T Esakkidurai; M Kumarraja; K Pitchumani

    2003-04-01

    Phenol is nitrated regioselectively by fuming nitric acid inside the cages of faujasite zeolites (dependent on the loading level) and a remarkable orthoselectivity is observed in solid state nitration. Toluene and chlorobenzene also containing ortho-/para-orienting substituents, undergo faster nitration, though the regioselectivity is less significant in zeolite media. The results are explained on the basis of diffusion and binding of phenol inside zeolite, which facilitate regioselectivity (and which is absent in toluene and chlorobenzene). Other advantages of employing zeolites as media for mild and selective nitration are also highlighted.

  16. Bambusurils as effective ion caging agents: Does desolvation guide conformation?

    Science.gov (United States)

    Cova, Tânia F. G. G.; Nunes, Sandra C. C.; Pinho e Melo, Teresa M. V. D.; Pais, Alberto A. C. C.

    2017-03-01

    Water soluble bambusurils can bind and isolate inorganic anions in the center of the hydrophobic cavity, with high affinity and selectivity. This makes them appealing anion carriers and ion transporters for a wide range of biomedical applications, including in ion-channel diseases of the muscles, bones and brain. For understanding the bambusuril ion caging ability in aqueous media, molecular dynamics simulations, including free energy calculations are used. It is seen that the ion is hermetically sealed inside the cavity, as a result of a concerted action involving conformation and desolvation of both ion and bambusuril cavity.

  17. SAMURAI-TPC: Field Cage Design and Prototyping

    Science.gov (United States)

    Lu, F.; Barney, J.; Chajecki, Z.; Chan, C. F.; Dunn, J. W.; Estee, J.; Gilbert, J.; Lynch, W. G.; Shane, R.; Tsang, M. B.; McIntosh, A. B.; Yenello, S. J.; Famiano, M.; Isobe, T.; Sakurai, H.; Taketani, A.; Murakami, T.; Samurai-Tpc Collaboration

    2011-10-01

    The SAMURAI-TPC is a time-projection chamber to be used in conjunction with the SAMURAI spectrometer being built at the Radioactive Isotope Beam Facility at RIKEN, Japan. It will be used to measure charged pions, protons and light ions. The pi+/pi- ratios from heavy-ion collisions should provide constraints on the asymmetry term in the nuclear equation of state at densities about twice saturation density. In this talk, the design and operation of the field cage, an essential part of the detector, will be discussed, along with the results of prototype testing. This work is supported by the Department of Energy under Grant DE-SC0004835.

  18. Concerning the Optimal Salt Bridge for Trp-cage Stabilization†

    Science.gov (United States)

    Williams, D. Victoria; Byrne, Aimee; Stewart, James; Andersen, Niels H.

    2011-01-01

    Gai and co-workers (Bunagan, M. R. (2006) J. Phys. Chem. B 110, 3759-3763) reported computational design studies suggesting that a D9E mutation would stabilize the Trp-cage. Experimental studies for this mutation were reported in 2008 (Hudaky, P. (2008) Biochemistry 47, 1007-1016); the authors suggested that [D9E]-TC5b presented a more compact, and melting resistant structure due to the “optimal distance between the two sides of the molecule”. Nonetheless, the authors reported essentially the same CD melting temperature, 38±0.3 °C, for TC5b and its [D9E] mutant. In this study, a more stable Trp-cage, DAYAQ WLKDG GPSSG RPPPS, was examined by NMR and CD with the following mutations: [D9E], [D9R,R16E], [R16Orn], [D9E,R16Orn], [R16K], and [D9E,R16K]. Of these, the [D9E]-mutant displayed the smallest acidification induced change in the apparent Tm. In analogy to the prior study, the CD melts of TC10b and its [D9E] mutant were, however, very similar; all of the other mutations were significantly fold destabilizing by all measures. A detailed analysis indicates that the original D9/R16 salt bridge is optimal with regard to fold cooperativity and fold stabilization. Evidence for salt-bridging is also provided for a swapped pair, the [D9R,R16E]-mutant. Model systems reveal that an ionized aspartate at the C-terminus of a helix significantly decreases intrinsic helicity, a requirement for Trp-cage fold stability. The CD evidence which was cited as supporting increased fold stability for the [D9E]-TC5b at higher temperatures appears to be a reflection of increased helix stability in both the folded and unfolded state rather than a more favorable salt bridge. The present study also provides evidence for other Trp-cage stabilizing roles of the R16 sidechain. PMID:21222485

  19. Design of Automated Rotory Cage Type Fixture for Cylinder Block

    Directory of Open Access Journals (Sweden)

    Y.S.Kapnichor

    2014-08-01

    Full Text Available Project gives feasible solution to move and rotate the component with full proofing fixturing for special purpose operations like drilling, Tapping, deburring, washing, drying involve in manufacturing and assembly unit of industry. Rotary cage type fixture is made for handling the cylinder head inside the cleaning machine use for making fully ready component before assembly operation .System is useful to save time manpower and deliver perfect cleaned and dry component .system involved all the mechanical components along with the sensors used to restrict the rotating operations, stop and go operations etc.

  20. Preinjector for Linac 1, inside the Faraday cage

    CERN Multimedia

    1974-01-01

    For a description of the Linac 1 preinjector, please see first 7403070X. Here, the view is towards the upper level of the Faraday cage. Far to the right, a technician is peering through the service door. The huge box-shaped cubicle is the electronics platform, at 520 kV potential during operation. The "bull eye" at the left back sits at the top end of the accelerating column (see 7403081X) and houses the ion source with its electronics (see 7403083X). The SAMES generator, providing the 520 kV HV (7403074) sits on the floor and is not visible here.

  1. A high-precision instrument for analyzing nonlinear dynamic behavior of bearing cage

    Science.gov (United States)

    Yang, Z.; Chen, H.; Yu, T.; Li, B.

    2016-08-01

    The high-precision ball bearing is fundamental to the performance of complex mechanical systems. As the speed increases, the cage behavior becomes a key factor in influencing the bearing performance, especially life and reliability. This paper develops a high-precision instrument for analyzing nonlinear dynamic behavior of the bearing cage. The trajectory of the rotational center and non-repetitive run-out (NRRO) of the cage are used to evaluate the instability of cage motion. This instrument applied an aerostatic spindle to support and spin test the bearing to decrease the influence of system error. Then, a high-speed camera is used to capture images when the bearing works at high speeds. A 3D trajectory tracking software tema Motion is used to track the spot which marked the cage surface. Finally, by developing the matlab program, a Lissajous' figure was used to evaluate the nonlinear dynamic behavior of the cage with different speeds. The trajectory of rotational center and NRRO of the cage with various speeds are analyzed. The results can be used to predict the initial failure and optimize cage structural parameters. In addition, the repeatability precision of instrument is also validated. In the future, the motorized spindle will be applied to increase testing speed and image processing algorithms will be developed to analyze the trajectory of the cage.

  2. Evaluation of cage micro-environment of mice housed on various types of bedding materials

    Science.gov (United States)

    Smith, E.; Stockwell, J.D.; Schweitzer, I.; Langley, S.H.; Smith, A.L.

    2004-01-01

    A variety of environmental factors can affect the outcomes of studies using laboratory rodents. One such factor is bedding. Several new bedding materials and processing methods have been introduced to the market in recent years, but there are few reports of their performance. In the studies reported here, we have assessed the cage micro-environment (in-cage ammonia levels, temperature, and humidity) of mice housed on various kinds of bedding and their combinations. We also compared results for bedding supplied as Nestpaks versus loose bedding. We studied C57BL/6J mice (commonly used) and NOD/LtJ mice (heavy soilers) that were maintained, except in one study, in static duplex cages. In general, we observed little effect of bedding type on in-cage temperature or humidity; however, there was considerable variation in ammonia concentrations. The lowest ammonia concentrations occurred in cages housing mice on hardwood bedding or a mixture of corncob and alpha cellulose. In one experiment comparing the micro-environments of NOD/LtJ male mice housed on woodpulp fiber bedding in static versus ventilated caging, we showed a statistically significant decrease in ammonia concentrations in ventilated cages. Therefore, our data show that bedding type affects the micro-environment in static cages and that effects may differ for ventilated cages, which are being used in vivaria with increasing frequency.

  3. A high-precision instrument for analyzing nonlinear dynamic behavior of bearing cage.

    Science.gov (United States)

    Yang, Z; Chen, H; Yu, T; Li, B

    2016-08-01

    The high-precision ball bearing is fundamental to the performance of complex mechanical systems. As the speed increases, the cage behavior becomes a key factor in influencing the bearing performance, especially life and reliability. This paper develops a high-precision instrument for analyzing nonlinear dynamic behavior of the bearing cage. The trajectory of the rotational center and non-repetitive run-out (NRRO) of the cage are used to evaluate the instability of cage motion. This instrument applied an aerostatic spindle to support and spin test the bearing to decrease the influence of system error. Then, a high-speed camera is used to capture images when the bearing works at high speeds. A 3D trajectory tracking software tema Motion is used to track the spot which marked the cage surface. Finally, by developing the matlab program, a Lissajous' figure was used to evaluate the nonlinear dynamic behavior of the cage with different speeds. The trajectory of rotational center and NRRO of the cage with various speeds are analyzed. The results can be used to predict the initial failure and optimize cage structural parameters. In addition, the repeatability precision of instrument is also validated. In the future, the motorized spindle will be applied to increase testing speed and image processing algorithms will be developed to analyze the trajectory of the cage.

  4. Abnormal behavior in caged birds kept as pets.

    Science.gov (United States)

    van Hoek, C S; ten Cate, C

    1998-01-01

    There are a limited number of studies dealing with abnormal behavior in caged birds kept as pets. However, these studies demonstrate the presence of abnormal behavior in both songbirds and parrots. Ethological studies on these birds, as well as studies on domestic and zoo birds, indicate that inappropriate rearing and housing conditions may lead to behavioral abnormalities. Together these data indicate that behavioral abnormalities occur among both wild-caught and domesticated pet birds. The severity and magnitude of these abnormalities is probably underestimated, and there is a need for systematic studies on the nature, origin, variability, species-specificity, and reversibility of behavioral problems in pet birds. Abnormal behavior in caged birds may to some extent be prevented and reduced by environmental enrichment. However, most enrichment studies are anecdotal and not based on a thorough analysis of the behavioral abnormalities, which may lead to measures resulting in a reduction of symptoms rather than the underlying causes. Although it is likely that several of these problems could be reduced by modifying rearing and housing conditions, the current insights into the causal mechanisms underlying abnormal behavior of domesticated and wild-caught pet birds are limited, as are the insights into the possibilities of preventing or curing abnormal behavior.

  5. Protection characteristics of a Faraday cage compromised by lightning burnthrough.

    Energy Technology Data Exchange (ETDEWEB)

    Warne, Larry Kevin; Bystrom, Edward; Jorgenson, Roy Eberhardt; Montoya, Sandra L.; Merewether, Kimball O.; Coats, Rebecca Sue; Martinez, Leonard E.; Jojola, John M.

    2012-01-01

    A lightning flash consists of multiple, high-amplitude but short duration return strokes. Between the return strokes is a lower amplitude, continuing current which flows for longer duration. If the walls of a Faraday cage are made of thin enough metal, the continuing current can melt a hole through the metal in a process called burnthrough. A subsequent return stroke can couple energy through this newly-formed hole. This LDRD is a study of the protection provided by a Faraday cage when it has been compromised by burnthrough. We initially repeated some previous experiments and expanded on them in terms of scope and diagnostics to form a knowledge baseline of the coupling phenomena. We then used a combination of experiment, analysis and numerical modeling to study four coupling mechanisms: indirect electric field coupling, indirect magnetic field coupling, conduction through plasma and breakdown through the hole. We discovered voltages higher than those encountered in the previous set of experiments (on the order of several hundreds of volts).

  6. Construction of silica-enhanced S-layer protein cages.

    Science.gov (United States)

    Schuster, D; Küpcü, S; Belton, D J; Perry, C C; Stöger-Pollach, M; Sleytr, U B; Pum, D

    2013-03-01

    The work presented here shows for the first time that it is possible to silicify S-layer coated liposomes and to obtain stable functionalized hollow nano-containers. For this purpose, the S-layer protein of Geobacillus stearothermophilus PV72/p2 was recombinantly expressed and used for coating positively charged liposomes composed of dipalmitoylphosphatidylcholine, cholesterol and hexadecylamine in a molar ratio of 10:5:4. Subsequently, plain (uncoated) liposomes and S-layer coated liposomes were silicified. Determination of the charge of the constructs during silicification allowed the deposition process to be followed. After the particles had been silicified, lipids were dissolved by treatment with Triton X-100 with the release of previously entrapped fluorescent dyes being determined by fluorimetry. Both, ζ-potential and release experiments showed differences between silicified plain liposomes and silicified S-layer coated liposomes. The results of the individual preparation steps were examined by embedding the respective assemblies in resin, ultrathin sectioning and inspection by bright-field transmission electron microscopy (TEM). Energy filtered TEM confirmed the successful construction of S-layer based silica cages. It is anticipated that this approach will provide a key to enabling technology for the fabrication of nanoporous protein cages for applications ranging from nano medicine to materials science.

  7. Automated Operant Conditioning in the Mouse Home Cage

    Science.gov (United States)

    Francis, Nikolas A.; Kanold, Patrick O.

    2017-01-01

    Recent advances in neuroimaging and genetics have made mice an advantageous animal model for studying the neurophysiology of sensation, cognition, and locomotion. A key benefit of mice is that they provide a large population of test subjects for behavioral screening. Reflex-based assays of hearing in mice, such as the widely used acoustic startle response, are less accurate than operant conditioning in measuring auditory processing. To date, however, there are few cost-effective options for scalable operant conditioning systems. Here, we describe a new system for automated operant conditioning, the Psibox. It is assembled from low cost parts, designed to fit within typical commercial wire-top cages, and allows large numbers of mice to train independently in their home cages on positive reinforcement tasks. We found that groups of mice trained together learned to accurately detect sounds within 2 weeks of training. In addition, individual mice isolated from groups also showed good task performance. The Psibox facilitates high-throughput testing of sensory, motor, and cognitive skills in mice, and provides a readily available animal population for studies ranging from experience-dependent neural plasticity to rodent models of mental disorders. PMID:28298887

  8. Electromechanical interaction in rotordynamics of cage induction motors

    Science.gov (United States)

    Holopainen, Timo P.; Tenhunen, Asmo; Arkkio, Antero

    2005-06-01

    Eccentric rotor motion induces an unbalanced magnetic pull between the rotor and stator of cage induction motors. Recently, a linear parametric model of this eccentricity force due to the arbitrary rotor motion was presented. The purpose of this study is to combine this electromagnetic force model with a simple mechanical rotor model, and further, to demonstrate the rotordynamic response induced by this electromechanical interaction. An electromechanical rotor model is derived on the basis of the Jeffcott rotor with two additional variables for the harmonic currents of the rotor cage. Applying this model, the rotordynamic effects of electromechanical interaction were studied. Three induction motors were used in the numerical examples. The electromechanical parameters of these motors were estimated from the numerical simulations carried out separately. The results obtained show that the electromechanical interaction may decrease the natural frequencies of the rotor, induce additional damping or cause rotordynamic instability. These interaction effects are most significant in motors operating at or near the first bending critical speed. Excluding the potential rotordynamic instability, the numerical results indicate that the electromechanical interaction reduces effectively the unbalance response close to the first bending critical speed.

  9. Looking for a bulk point

    CERN Document Server

    Maldacena, Juan; Zhiboedov, Alexander

    2015-01-01

    We consider Lorentzian correlators of local operators. In perturbation theory, singularities occur when we can draw a position-space Landau diagram with null lines. In theories with gravity duals, we can also draw Landau diagrams in the bulk. We argue that certain singularities can arise only from bulk diagrams, not from boundary diagrams. As has been previously observed, these singularities are a clear diagnostic of bulk locality. We analyze some properties of these perturbative singularities and discuss their relation to the OPE and the dimensions of double-trace operators. In the exact nonperturbative theory, we expect no singularity at these locations. We prove this statement in 1+1 dimensions by CFT methods.

  10. Bulk nano-crystalline alloys

    OpenAIRE

    T.-S. Chin; Lin, C. Y.; Lee, M.C.; R.T. Huang; S. M. Huang

    2009-01-01

    Bulk metallic glasses (BMGs) Fe–B–Y–Nb–Cu, 2 mm in diameter, were successfully annealed to become bulk nano-crystalline alloys (BNCAs) with α-Fe crystallite 11–13 nm in size. A ‘crystallization-and-stop’ model was proposed to explain this behavior. Following this model, alloy-design criteria were elucidated and confirmed successful on another Fe-based BMG Fe–B–Si–Nb–Cu, 1 mm in diameter, with crystallite sizes 10–40 nm. It was concluded that BNCAs can be designed in general by the proposed cr...

  11. Development of an integrated CAD-FEA system for patient-specific design of spinal cages.

    Science.gov (United States)

    Zhang, Mingzheng; Pu, Fang; Xu, Liqiang; Zhang, Linlin; Liang, Hang; Li, Deyu; Wang, Yu; Fan, Yubo

    2017-03-01

    Spinal cages are used to create a suitable mechanical environment for interbody fusion in cases of degenerative spinal instability. Due to individual variations in bone structures and pathological conditions, patient-specific cages can provide optimal biomechanical conditions for fusion, strengthening patient recovery. Finite element analysis (FEA) is a valuable tool in the biomechanical evaluation of patient-specific cage designs, but the time- and labor-intensive process of modeling limits its clinical application. In an effort to facilitate the design and analysis of patient-specific spinal cages, an integrated CAD-FEA system (CASCaDeS, comprehensive analytical spinal cage design system) was developed. This system produces a biomechanical-based patient-specific design of spinal cages and is capable of rapid implementation of finite element modeling. By comparison with commercial software, this system was validated and proven to be both accurate and efficient. CASCaDeS can be used to design patient-specific cages with a superior biomechanical performance to commercial spinal cages.

  12. Standard methods for maintaining adult Apis mellifera in cages under in vitro laboratory conditions

    NARCIS (Netherlands)

    Williams, G.R.; Alaux, C.; Costa, C.; Csaki, C.; Steen, van der J.J.M.

    2013-01-01

    Adult honey bees are maintained in vitro in laboratory cages for a variety of purposes. For example, researchers may wish to perform experiments on honey bees caged individually or in groups to study aspects of parasitology, toxicology, or physiology under highly controlled conditions, or they may c

  13. Mercury accumulation in caged Corbicula: rate of uptake and seasonal variation.

    Science.gov (United States)

    Neufeld, Douglas S G

    2010-09-01

    The uptake and seasonal fluctuations of total mercury were followed in caged and uncaged Asiatic clams, Corbicula fluminea, over a 1-year period in South River, Virginia. Mercury was rapidly accumulated in clams transplanted from a nominally uncontaminated site into cages on the contaminated South River, reaching 0.99 microg g(-1) dry mass within the first month. Resident clams moved to cages had higher mercury contents after the first month (2.04 microg g(-1) dry mass) and at all subsequent times in the study. Large monthly fluctuations in mercury were noted for both resident caged and transplant caged clams with a notable peak occurring in early spring (4.31 microg g(-1) dry mass in resident caged clams). Tissue mass of caged clams steadily increased through the winter and early spring. Adjustment of mercury concentrations for tissue mass changes indicated that the changes in mercury contents were primarily due to uptake/release rather than changes in tissue mass (concentration/dilution). The present study demonstrates the utility of using caged Corbicula as mercury biomonitors and illustrates the importance of accounting for large, short-term changes of mercury content in Corbicula when designing long-term biomonitoring studies.

  14. International standardization of cage designs and feeding regimes for honey bee in vitro experiments

    Science.gov (United States)

    The aim of this study was to improve and standardize cage systems for maintaining adult honey bee workers under in vitro laboratory conditions. To achieve this goal, we experimentally evaluated the impact of different cages, developed by scientists of the international research network COLOSS (Preve...

  15. A generic strategy for pharmacological caging of growth factors for tissue engineering.

    Science.gov (United States)

    Karlsson, Maria; Lienemann, Philipp S; Sprossmann, Natallia; Heilmann, Katharina; Brummer, Tilman; Lutolf, Matthias P; Ehrbar, Martin; Weber, Wilfried

    2013-07-01

    The caging of small molecules has revolutionized biological research by providing a means to regulate a wide range of processes. Here we report on a generic pharmacological method to cage proteins in a similar fashion. The present approach is of value in both fundamental and applied research, e.g. in tissue engineering.

  16. A pyrrolo-tetrathiafulvalene cage: Synthesis and X-ray crystal structure

    DEFF Research Database (Denmark)

    Nielsen, Kent A.; Jeppesen, Jan O.; Levillain, Eric;

    2002-01-01

    A novel type of tetrathiafulvalene-cage 4 containing three monopyrrolo-tetrathiafulvalene units has been prepared employing a general and efficient synthetic approach. X-ray crystal structure analysis revealed that the cage is able to accommodate solvent molecules within a cavity in the solid state....

  17. Improving aeration for efficient oxygenation in sea bass sea cages. Blood, brain and gill histology

    Directory of Open Access Journals (Sweden)

    Berillis Panagiotis

    2016-01-01

    Full Text Available An air diffusion based system (Airx was developed to control the dissolved oxygen levels in aquaculture sea cages. The system was introduced and then tested for 37 days in a sea bass sea cage (aerated cage. A second sea bass sea cage, without the AirX, was used as a control. Oxygen levels were measured in both cages at the start of the trial, before the AirX system was introduced, and during the working period of the AirX system. Fish samples were collected 15 days after the AirX system was introduced and at the end of the experiment. Blood smears were prepared and examined microscopically. Erythrocyte major axis, minor axis and area of fish erythrocytes were measured. Leucocyte differentiation was also examined. In the control cage, the fish had significantly larger red blood cells when compared with the red blood cells of the fish in the aerated cage. Histological examination of the gills and brain revealed no morphological differences or alterations between the two groups of fish. This study demonstrated that an air diffuser system could improve the water quality of fish farmed in sea cages and enhance sea bass physiological performance, especially if DO levels fall below 60% oxygen saturation.

  18. Longitudinal bulk acoustic mass sensor

    DEFF Research Database (Denmark)

    Hales, Jan Harry; Teva, Jordi; Boisen, Anja

    2009-01-01

    A polycrystalline silicon longitudinal bulk acoustic cantilever is fabricated and operated in air at 51 MHz. A mass sensitivity of 100 Hz/fg (1 fg=10(-15) g) is obtained from the preliminary experiments where a minute mass is deposited on the device by means of focused ion beam. The total noise i...

  19. The Universe With Bulk Viscosity

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Exact solutions for a model with variable G, A and bulk viscosity areobtained. Inflationary solutions with constant (de Sitter-type) and variable energydensity are found. An expanding anisotropic universe is found to isotropize duringits expansion but a static universe cannot isotropize. The gravitational constant isfound to increase with time and the cosmological constant decreases with time asAo∝t-2.

  20. Parameters estimation of squirrel-cage induction motors using ANN and ANFIS

    Directory of Open Access Journals (Sweden)

    Mehdi Ahmadi Jirdehi

    2016-03-01

    Full Text Available In the transient behavior analysis of a squirrel-cage induction motor, the parameters of the single-cage and double-cage models are studied. These parameters are usually hard to obtain. This paper presents two new methods to predict the induction motor parameters in the single-cage and double-cage models based on artificial neural network (ANN and adaptive neuro-fuzzy inference system (ANFIS. For this purpose, the experimental data (manufacturer data of 20 induction motors with the different power are used. The experimental data are including of the starting torque and current, maximum torque, full load sleep, efficiency, rated active power and reactive power. The obtained results from the proposed ANN and ANFIS models are compared with each other and with the experimental data, which show a good agreement between the predicted values and the experimental data. But the proposed ANFIS model is more accurate than the proposed ANN model.

  1. Dynamic Analysis of Flexible Cage of High-speed Angular Contact Ball Bearing

    Institute of Scientific and Technical Information of China (English)

    邓四二; 谢鹏飞; 杨海生; 高银涛

    2012-01-01

    A dynamics formula was established for the flexible cage of high-speed angular contact ball bearing. A modified Craig-Bampton component mode synthetic method was used to establish the formula with regard to the flexibility of cage and based on a dynamic analysis of angular contact ball bearing, and a rigid-flexible multi-body dynamic analysis program was developed using ADAMS, which is verified by a computation example of Gupta. The results show that it' s not likely to keep the rotation smoothness of cage when the ratio of pocket clearance to guiding clearance and the ratio of radial load to axial load become too large or too small. By comparison, the flexible cage runs more smoothly than the rigid cage.

  2. Magnetotactic Bacterial Cages as Safe and Smart Gene Delivery Vehicles

    KAUST Repository

    Alsaiari, Shahad K.

    2016-07-27

    In spite of the huge advances in the area of synthetic carriers, their efficiency still poorly compares to natural vectors. Herein, we report the use of unmodified magnetotactic bacteria as a guidable delivery vehicle for DNA functionalized gold nanoparticles (AuNPs). High cargo loading is established under anaerobic conditions (bacteria is alive) through endocytosis where AuNPs are employed as transmembrane proteins mimics (facilitate endocytosis) as well as imaging agents to verify and quantify loading and release. The naturally bio-mineralized magnetosomes, within the bacteria, induce heat generation inside bacteria through magnetic hyperthermia. Most importantly after exposing the system to air (bacteria is dead) the cell wall stays intact providing an efficient bacterial vessel. Upon incubation with THP-1 cells, the magnetotactic bacterial cages (MBCs) adhere to the cell wall and are directly engulfed through the phagocytic activity of these cells. Applying magnetic hyperthermia leads to the dissociation of the bacterial microcarrier and eventual release of cargo.

  3. Classical Effective Field Theory and Caged Black Holes

    CERN Document Server

    Kol, Barak

    2007-01-01

    Matched Asymptotic Expansion (MAE) is a useful technique in General Relativity and other fields whenever interaction takes place between physics at two different length scales. Here MAE is argued to be equivalent quite generally to Classical Effective Field Theory (ClEFT) where one (or more) of the zones is replaced by an effective theory whose terms are organized in order of increasing irrelevancy, as demonstrated by Goldberger and Rothstein in a certain gravitational context. The ClEFT perspective has advantages as the procedure is clearer, it allows a representation via Feynman diagrams, and divergences can be regularized and renormalized in standard field theoretic methods. As a side product we obtain a wide class of classical examples of regularization and renormalization, concepts which are usually associated with Quantum Field Theories. We demonstrate these ideas through the thermodynamics of caged black holes, both simplifying the non-rotating case, and computing the rotating case. In particular we ar...

  4. Resonance Spectra of Caged Stringy Black Hole and Its Spectroscopy

    CERN Document Server

    Sakalli, I

    2015-01-01

    The Maggiore's method (MM), which evaluates the transition frequency that appears in the adiabatic invariant from the highly damped quasinormal mode (QNM) frequencies, is used to investigate the entropy/area spectra of the Garfinkle--Horowitz--Strominger black hole (GHSBH). Instead of the ordinary QNMs, we compute the boxed QNMs (BQNMs) that are the characteristic resonance spectra of the confined scalar fields in the GHSBH geometry. For this purpose, we assume that the GHSBH has a confining cavity (mirror) placed in the vicinity of the event horizon. We then show how the complex resonant frequencies of the caged GHSBH are computed using the Bessel differential equation that arises when the scalar perturbations around the event horizon are considered. Although the entropy/area is characterized by the GHSBH parameters, their quantization is shown to be independent of those parameters. However, both spectra are equally spaced.

  5. Resonance Spectra of Caged Stringy Black Hole and Its Spectroscopy

    Directory of Open Access Journals (Sweden)

    I. Sakalli

    2015-01-01

    quasinormal mode (QNM frequencies, is used to investigate the entropy/area spectra of the Garfinkle–Horowitz–Strominger black hole (GHSBH. Instead of the ordinary QNMs, we compute the boxed QNMs (BQNMs that are the characteristic resonance spectra of the confined scalar fields in the GHSBH geometry. For this purpose, we assume that the GHSBH has a confining cavity (mirror placed in the vicinity of the event horizon. We then show how the complex resonant frequencies of the caged GHSBH are computed using the Bessel differential equation that arises when the scalar perturbations around the event horizon are considered. Although the entropy/area is characterized by the GHSBH parameters, their quantization is shown to be independent of those parameters. However, both spectra are equally spaced.

  6. Chemistry and biology of the caged Garcinia xanthones.

    Science.gov (United States)

    Chantarasriwong, Oraphin; Batova, Ayse; Chavasiri, Warinthorn; Theodorakis, Emmanuel A

    2010-09-03

    Natural products have been a great source of many small molecule drugs for various diseases. In spite of recent advances in biochemical engineering and fermentation technologies that allow us to explore microorganisms and the marine environment as alternative sources of drugs, more than 70 % of the current small molecule therapeutics derive their structures from plants used in traditional medicine. Natural-product-based drug discovery relies heavily on advances made in the sciences of biology and chemistry. Whereas biology aims to investigate the mode of action of a natural product, chemistry aims to overcome challenges related to its supply, bioactivity, and target selectivity. This review summarizes the explorations of the caged Garcinia xanthones, a family of plant metabolites that possess a unique chemical structure, potent bioactivities, and a promising pharmacology for drug design and development.

  7. CAGE Analysis of China’s Trade Globalization

    Directory of Open Access Journals (Sweden)

    Emmanuel Olusegun STOBER

    2014-06-01

    Full Text Available Gravity model of international trade states that trade interaction between two countries is in direct proportion to their size measured by Gross Domestic Product and in inverse proportion to the geographic distance. Conley and Ligon (2001 argued that the relevant economic distance between countries is often not the geographic distance. Thus, this study uses original datasets on economic distance to structure observed variations, to decompose the multidimensional CAGE distance framework of globalization derived from the Newton’s Law of gravitation as it applies to China’s international interaction, to evaluate bilateral trade patterns in identifying and prioritizing the importance of cross-border flows and differences that accounted for the development of China’s global strategies. This study confirms that distance must be accounted for in the decision making of any country’s globalization process or any firm’s global expansion as the effects on cross-border economic activities are enormous.

  8. Cage Versus Noncage Laying-Hen Housings: Respiratory Exposures.

    Science.gov (United States)

    Arteaga, Veronica; Mitchell, Diane; Armitage, Tracey; Tancredi, Daniel; Schenker, Marc; Mitloehner, Frank

    2015-01-01

    The objective of this study was to compare the personal respiratory exposures of poultry workers in three different types of layer housing under commercial production conditions. Workers were randomly assigned to each of conventional cage, enriched cage, and aviary barns in a crossover repeated-measures design for three observation periods over the hens' lifetime. Inhalable and fine particulate matter (PM) and endotoxin in both size fractions were assessed by personal and area samplers over the work shift. Concentrations of inhalable PM, PM2.5 (PM with an aerodynamic diameter <2.5 μm), and endotoxin in both size fractions were higher in aviary than either the conventional or enriched barns. Geometric means (95% confidence intervals [CIs]) of inhalable PM and endotoxin for the aviary, conventional, and enriched barns were 8.9 (6.8-11.5) mg/m(3) and 7517.9 (5403.2-10,460.2) EU/m(3), 3.7 (2.8-4.8) mg/m(3) and 1655.7 (1144.6-2395.2) EU/m(3), 2.4 (1.8-3.3) mg/m(3) and 1404.8 (983.3-2007.0) EU/m(3), respectively. Area samplers recorded a lower mean inhalable PM concentration and higher PM2.5 concentration than personal samplers. Ammonia concentrations were low throughout three monitoring seasons. These findings show that the aviary barns pose higher respiratory exposures to poultry workers than either conventional or enriched barns.

  9. Electromechanical interaction in rotordynamics of cage induction motors

    Energy Technology Data Exchange (ETDEWEB)

    Holopainen, T.P. [VTT Industrial Systems, Espoo (Finland)

    2004-08-01

    Electromagnetic fields in the air gap of an electric machine produce electromagnetic forces between the rotor and stator. The total force exerted on the rotor due to the eccentric rotor position is called the unbalanced magnetic pull. This eccentricity force is directed roughly over the shortest air gap. At low frequencies, the vibration amplitudes of flexural modes may be large enough to couple the electromagnetic system to the mechanical one. This electromechanical inter-action changes the vibration behaviour of the system. The main purpose of this dissertation is to reveal the main rotordynamic consequences induced by the electromechanical interaction in cage induction motors. Another goal is to achieve this by deriving a simple and representative electro mechanical rotor model with physical variables and parameters. In this study, a new parametric model was derived for the unbalanced magnetic pull induced by an arbitrary rotor motion in transient operation. The parameters of this model can be determined analytically from the basis of the machine characteristics or estimated numerically as in this study. To estimate the parameters, an efficient numerical method was developed from the analysis of impulse response. The numerical results showed that the simple electromagnetic force model, together with the estimated parameters, predicts the unbalanced magnetic pull fairly accurately. An electromechanical rotor model was derived by combining the Jeffcott rotor model with the simple electromagnetic force model, including two additional variables for the harmonic currents of the rotor cage. Applying this model, the rotordynamic effects of electromechanical interaction were studied. Three induction motors were used in the numerical examples. The results obtained show that the electromechanical interaction may decrease the flexural frequencies of the rotor, induce additional damping or cause rotordynamic instability. These interaction effects are most significant in

  10. Bulk Superconductors in Mobile Application

    Science.gov (United States)

    Werfel, F. N.; Delor, U. Floegel-; Rothfeld, R.; Riedel, T.; Wippich, D.; Goebel, B.; Schirrmeister, P.

    We investigate and review concepts of multi - seeded REBCO bulk superconductors in mobile application. ATZ's compact HTS bulk magnets can trap routinely 1 T@77 K. Except of magnetization, flux creep and hysteresis, industrial - like properties as compactness, power density, and robustness are of major device interest if mobility and light-weight construction is in focus. For mobile application in levitated trains or demonstrator magnets we examine the performance of on-board cryogenics either by LN2 or cryo-cooler application. The mechanical, electric and thermodynamical requirements of compact vacuum cryostats for Maglev train operation were studied systematically. More than 30 units are manufactured and tested. The attractive load to weight ratio is more than 10 and favours group module device constructions up to 5 t load on permanent magnet (PM) track. A transportable and compact YBCO bulk magnet cooled with in-situ 4 Watt Stirling cryo-cooler for 50 - 80 K operation is investigated. Low cooling power and effective HTS cold mass drives the system construction to a minimum - thermal loss and light-weight design.

  11. Effect of 2 Bedding Materials on Ammonia Levels in Individually Ventilated Cages.

    Science.gov (United States)

    Koontz, Jason M; Kumsher, David M; Kelly, Richard; Stallings, Jonathan D

    2016-01-01

    This study sought to identify an optimal rodent bedding and cage-change interval to establish standard procedures for the IVC in our rodent vivarium. Disposable cages were prefilled with either corncob or α-cellulose bedding and were used to house 2 adult Sprague-Dawley rats (experimental condition) or contained no animals (control). Rats were observed and intracage ammonia levels measured daily for 21 d. Intracage ammonia accumulation became significant by day 8 in experimental cages containing α-cellulose bedding, whereas experimental cages containing corncob bedding did not reach detectable levels of ammonia until day 14. In all 3 experimental cages containing α-cellulose, ammonia exceeded 100 ppm (our maximum acceptable limit) by day 11. Two experimental corncob cages required changing at days 16 and 17, whereas the remaining cage containing corncob bedding lasted the entire 21 d without reaching the 100-ppm ammonia threshold. These data suggests that corncob bedding provides nearly twice the service life of α-cellulose bedding in the IVC system.

  12. Effect of 2 Bedding Materials on Ammonia Levels in Individually Ventilated Cages

    Science.gov (United States)

    Koontz, Jason M; Kumsher, David M; III, Richard Kelly; Stallings, Jonathan D

    2016-01-01

    This study sought to identify an optimal rodent bedding and cage-change interval to establish standard procedures for the IVC in our rodent vivarium. Disposable cages were prefilled with either corncob or α-cellulose bedding and were used to house 2 adult Sprague–Dawley rats (experimental condition) or contained no animals (control). Rats were observed and intracage ammonia levels measured daily for 21 d. Intracage ammonia accumulation became significant by day 8 in experimental cages containing α-cellulose bedding, whereas experimental cages containing corncob bedding did not reach detectable levels of ammonia until day 14. In all 3 experimental cages containing α-cellulose, ammonia exceeded 100 ppm (our maximum acceptable limit) by day 11. Two experimental corncob cages required changing at days 16 and 17, whereas the remaining cage containing corncob bedding lasted the entire 21 d without reaching the 100-ppm ammonia threshold. These data suggests that corncob bedding provides nearly twice the service life of α-cellulose bedding in the IVC system. PMID:26817976

  13. Suitability of carbon fiber-reinforced polyetheretherketone cages for use as anterior struts following corpectomy.

    Science.gov (United States)

    Heary, Robert F; Parvathreddy, Naresh K; Qayumi, Zainab S; Ali, Naiim S; Agarwal, Nitin

    2016-08-01

    OBJECTIVE Fibular allograft remains a widely used strut for corpectomy surgeries. The amount of graft material that can be packed into an allograft strut has not been quantified. Cages are an alternative to fibular allograft for fusion surgeries. The authors of this study assessed the suitability of carbon fiber-reinforced polyetheretherketone (CFRP) cages for anterior corpectomy surgeries. They further explored the parameters known to affect fusion rates in clinical practice. METHODS Six fibular allografts were tested at standard lengths. Three sets of carbon fiber cages (Bengal, DePuy Spine), each with a different footprint size but the same lengths, were tested. The allografts and cages were wrapped in adhesive, fluid-tight transparent barriers and filled with oil. The volume and weight of the oil instilled as well as the implant footprints were measured. The fibular allografts and cages were tested at 20-, 40-, and 50-mm lengths. Two investigators independently performed all measurements 5 times. Five CFRP cubes (1 × 1 × 1 cm) were tested under pure compression, and load versus displacement curves were plotted to determine the modulus of elasticity. RESULTS Significantly more oil fit in the CFRP cages than in the fibular allografts (p Carbon fiber-reinforced polyetheretherketone cages can accommodate much more graft material than can fibular allografts. In clinical practice, the ability to deliver greater amounts of graft material following a corpectomy may improve fusion rates.

  14. Digestibility and behavior of dogs housed in kennels or metabolic cages

    Directory of Open Access Journals (Sweden)

    Tabyta Tamara Sabchuk

    2012-01-01

    Full Text Available The objective of the present study was to compare the apparent digestibility coefficients of a commercial dog food, fecal consistency and behavior of dogs housed in kennels and metabolic cages. Six adult Beagle dogs were distributed in cross-over experimental design, with six replicates per treatment. Dogs were housed in two environments: metabolic cages and in masonry kennels with solarium. Dogs were fed for a five-day adaptation period, and the five following days were used for total feces collection. Dogs behavior was recorded during a 48-h period, with 10-min intervals. Apparent digestibility coefficients were not different between treatments. However, dogs housed in metabolic cages produced lower weight and more consistent feces as compared with dogs housed in kennels. Dogs spent most of the time sleeping in both housing systems; however, dogs housed in the metabolic cages slept more than those in kennels. Stress-related behaviors (barking, whimpering, stereotypies, etc were observed for no longer than 15 minutes per day, and were not different between dogs in kennels or in cages. There is no difference in food digestibility evaluated in dogs housed in metabolic cages or kennels; however, dogs kept in metabolic cages eliminate drier feces and spend more time inactive than those kept in kennels.

  15. Individually ventilated cages cause chronic low-grade hypoxia impacting mice hematologically and behaviorally

    Science.gov (United States)

    York, Jason M.; McDaniel, Allison W.; Blevins, Neil A.; Guillet, Riley R.; Allison, Sarah O.; Cengel, Keith A.; Freund, Gregory G.

    2012-01-01

    Use of individually ventilated caging (IVC) systems for mouse-based laboratory investigation has dramatically increased. We found that without mice present, intra-cage oxygen concentration was comparable (21%) between IVC housing and ambient environment caging (AEC) that used wire top lids. However, when mice were housed 4-to-a-cage for 1 week, intra-cage oxygen dropped to 20.5% in IVC housing as compared to 21% for AEC housing. IVC intra-cage humidity was also elevated relative to AEC housing. Mice raised in IVC housing as compared to mice raised in AEC housing had higher RBC mass, hematocrit and hemoglobin concentrations. They also had elevated platelet counts but lower white blood cell counts. IVC mice relative to AEC mice had increased saccharin preference and increased fluid consumption but similar locomotion, food intake, social exploration and novel object recognition when tested in an AEC environment. Taken together, these data indicate that ventilated caging systems can have a 0.5% reduction from ambient oxygen concentration that is coupled to mouse red blood cell indices indicative of chronic exposure to a hypoxia. Importantly, IVC housing can impact behavioral testing for depressive-like behavior. PMID:22561683

  16. Effect of curcumin caged silver nanoparticle on collagen stabilization for biomedical applications.

    Science.gov (United States)

    Srivatsan, Kunnavakkam Vinjimur; Duraipandy, N; Begum, Shajitha; Lakra, Rachita; Ramamurthy, Usha; Korrapati, Purna Sai; Kiran, Manikantan Syamala

    2015-04-01

    The current study aims at understanding the influence of curcumin caged silver nanoparticle (CCSNP) on stability of collagen. The results indicated that curcumin caged silver nanoparticles efficiently stabilize collagen, indicated by enhanced tensile strength, fibril formation and viscosity. The tensile strength of curcumin caged silver nanoparticle cross-linked collagen and elongation at break was also found to be higher than glutaraldehyde cross-linked collagen. The physicochemical characteristics of curcumin caged nanoparticle cross-linked collagen exhibited enhanced strength. The thermal properties were also good with both thermal degradation temperature and hydrothermal stability higher than native collagen. CD analysis showed no structural disparity in spite of superior physicochemical properties suggesting the significance of curcumin caged nanoparticle mediated cross-linking. The additional enhancement in the stabilization of collagen could be attributed to multiple sites for interaction with collagen molecule provided by curcumin caged silver nanoparticles. The results of cell proliferation and anti-microbial activity assays indicated that curcumin caged silver nanoparticles promoted cell proliferation and inhibited microbial growth making it an excellent biomaterial for wound dressing application. The study opens scope for nano-biotechnological strategies for the development of alternate non-toxic cross-linking agents facilitating multiple site interaction thereby improving therapeutic values to the collagen for biomedical application.

  17. Computational design and fabrication of a novel bioresorbable cage for tibial tuberosity advancement application.

    Science.gov (United States)

    Castilho, Miguel; Rodrigues, Jorge; Vorndran, Elke; Gbureck, Uwe; Quental, Carlos; Folgado, João; Fernandes, Paulo R

    2017-01-01

    Tibial tuberosity advancement (TTA) is a promising method for the treatment of cruciate ligament rupture in dogs that usually implies the implantation of a titanium cage as bone implant. This cage is non-biodegradable and fails in providing adequate implant-bone tissue integration. The objective of this work is to propose a new process chain for designing and manufacturing an alternative biodegradable cage that can fulfill specific patient requirements. A three-dimensional finite element model (3D FEM) of the TTA system was first created to evaluate the mechanical environment at cage domain during different stages of the dog walk. The cage microstructure was then optimized using a topology optimization tool, which addresses the accessed local mechanical requirements, and at same time ensures the maximum permeability to allow nutrient and oxygen supply to the implant core. The designed cage was then biofabricated by a 3D powder printing of tricalcium phosphate cement. This work demonstrates that the combination of a 3D FEM with a topology optimization approach enabled the design of a novel cage for TTA application with tailored permeability and mechanical properties, that can be successfully 3D printed in a biodegradable bioceramic material. These results support the potential of the design optimization strategy and fabrication method to the development of customized and bioresorbable implants for bone repair.

  18. Growth of uniform CaGe2 films by alternating layer molecular beam epitaxy

    Science.gov (United States)

    Xu, Jinsong; Katoch, Jyoti; Ahmed, Adam S.; Pinchuk, Igor V.; Young, Justin R.; Johnston-Halperin, Ezekiel; Pelz, Jonathan; Kawakami, Roland K.

    2017-02-01

    Layered Zintl phase van der Waals (vdW) materials are of interest due to their strong spin-orbit coupling and potential for high mobility. Here, we report the successful growth of large area CaGe2 films, as a model of layered Zintl phase materials, on atomically flat Ge(111) substrates by molecular beam epitaxy (MBE) using an alternating layer growth (ALG) protocol. Reflection high energy electron diffraction (RHEED) patterns of the Ge buffer layer and CaGe2 indicate high quality two dimensional surfaces, which is further confirmed by atomic force microscopy (AFM), showing atomically flat and uniform CaGe2 films. The appearance of Laue oscillations in X-ray diffraction (XRD) and Kiessig fringes in the X-ray reflectivity (XRR), which are absent in co-deposited CaGe2, confirms the uniformity of the CaGe2 film and the smoothness of the interface. These results demonstrate a novel method of deposition of CaGe2 that could be also applied to other layered Zintl phase vdW materials. Also, the high quality of the CaGe2 film is promising for the exploration of novel properties of germanane.

  19. Low home cage social behaviors in BTBR T+tf/J mice during juvenile development.

    Science.gov (United States)

    Babineau, Brooke A; Yang, Mu; Berman, Robert F; Crawley, Jacqueline N

    2013-04-10

    BTBR T+tf/J (BTBR) is a genetically homogenous inbred strain of mice that displays abnormal social behaviors, deficits in vocalizations, and high levels of repetitive behaviors, relevant to the three diagnostic symptoms of autism spectrum disorder, leading to the use of this strain as a mouse model of autism. Comprehensive observations of BTBR social behaviors within the home cage during early stages of development have not been conducted. Here we evaluate the home cage behaviors of BTBR in two laboratory environments (NIMH, Bethesda, Maryland vs. UC Davis, Davis, California), starting from the day of weaning and continuing into adulthood. Extensive ethogram parameters were scored for BTBR in home cages that contained four BTBR conspecifics, versus home cages that contained four C57BL/6J (B6) conspecifics. BTBR were considerably less interactive than B6 in the home cage at both sites, as measured during the early dark stage of their circadian cycle. A novel home cage behavioral measure, frequency of long interactions, was found to be more frequent and of longer duration in B6 versus BTBR home cages across experimental sites. Significant strain differences in the occurrence of investigative and affiliative behaviors were also seen, however these findings were not fully consistent across the two testing sites. At the end of the 30-day home cage observation period, each seven-week old subject mouse was tested in the three-chambered social approach task. BTBR displayed lack of sociability and B6 displayed significant sociability, consistent with previous reports. Our findings reveal that BTBR engaged in lower levels of some components of spontaneous conspecific social interactions in the home cage environment throughout juvenile development, consistent with their deficits in juvenile and adult sociability as measured in specialized social tasks.

  20. Spiro annulation of cage polycycles via Grignard reaction and ring-closing metathesis as key steps

    Directory of Open Access Journals (Sweden)

    Sambasivarao Kotha

    2015-08-01

    Full Text Available A simple synthetic strategy to C2-symmetric bis-spiro-pyrano cage compound 7 involving ring-closing metathesis is reported. The hexacyclic dione 10 was prepared from simple and readily available starting materials such as 1,4-naphthoquinone and cyclopentadiene. The synthesis of an unprecedented octacyclic cage compound through intramolecular Diels–Alder (DA reaction as a key step is described. The structures of three new cage compounds 7, 12 and 18 were confirmed by single crystal X-ray diffraction studies.

  1. A Perspective on the Synthesis, Purification, and Characterization of Porous Organic Cages.

    Science.gov (United States)

    Briggs, Michael E; Cooper, Andrew I

    2017-01-10

    Porous organic cages present many opportunities in functional materials chemistry, but the synthetic challenges for these molecular solids are somewhat different from those faced in the areas of metal-organic frameworks, covalent-organic frameworks, or porous polymer networks. Here, we highlight the practical methods that we have developed for the design, synthesis, and characterization of imine porous organic cages using CC1 and CC3 as examples. The key points are transferable to other cages, and this perspective should serve as a practical guide to researchers who are new to this field.

  2. Genome-wide detection and analysis of hippocampus core promoters using DeepCAGE

    DEFF Research Database (Denmark)

    Valen, Eivind; Pascarella, Giovanni; Chalk, Alistair;

    2009-01-01

    in a given tissue. Here, we present a new method for high-throughput sequencing of 5' cDNA tags-DeepCAGE: merging the Cap Analysis of Gene Expression method with ultra-high-throughput sequence technology. We apply DeepCAGE to characterize 1.4 million sequenced TSS from mouse hippocampus and reveal a wealth...... of novel core promoters that are preferentially used in hippocampus: This is the most comprehensive promoter data set for any tissue to date. Using these data, we present evidence indicating a key role for the Arnt2 transcription factor in hippocampus gene regulation. DeepCAGE can also detect promoters...

  3. Bulk Moisture and Salinity Sensor

    Science.gov (United States)

    Nurge, Mark; Monje, Oscar; Prenger, Jessica; Catechis, John

    2013-01-01

    Measurement and feedback control of nutrient solutions in plant root zones is critical to the development of healthy plants in both terrestrial and reduced-gravity environments. In addition to the water content, the amount of fertilizer in the nutrient solution is important to plant health. This typically requires a separate set of sensors to accomplish. A combination bulk moisture and salinity sensor has been designed, built, and tested with different nutrient solutions in several substrates. The substrates include glass beads, a clay-like substrate, and a nutrient-enriched substrate with the presence of plant roots. By measuring two key parameters, the sensor is able to monitor both the volumetric water content and salinity of the nutrient solution in bulk media. Many commercially available moisture sensors are point sensors, making localized measurements over a small volume at the point of insertion. Consequently, they are more prone to suffer from interferences with air bubbles, contact area of media, and root growth. This makes it difficult to get an accurate representation of true moisture content and distribution in the bulk media. Additionally, a network of point sensors is required, increasing the cabling, data acquisition, and calibration requirements. measure the dielectric properties of a material in the annular space of the vessel. Because the pore water in the media often has high salinity, a method to measure the media moisture content and salinity simultaneously was devised. Characterization of the frequency response for capacitance and conductance across the electrodes was completed for 2-mm glass bead media, 1- to 2-mm Turface (a clay like media), and 1- to 2-mm fertilized Turface with the presence of root mass. These measurements were then used to find empirical relationships among capacitance (C), the dissipation factor (D), the volumetric water content, and the pore water salinity.

  4. Toughness of Bulk Metallic Glasses

    Directory of Open Access Journals (Sweden)

    Shantanu V. Madge

    2015-07-01

    Full Text Available Bulk metallic glasses (BMGs have desirable properties like high strength and low modulus, but their toughness can show much variation, depending on the kind of test as well as alloy chemistry. This article reviews the type of toughness tests commonly performed and the factors influencing the data obtained. It appears that even the less-tough metallic glasses are tougher than oxide glasses. The current theories describing the links between toughness and material parameters, including elastic constants and alloy chemistry (ordering in the glass, are discussed. Based on the current literature, a few important issues for further work are identified.

  5. Intermolecular hydrogen transfer between guest species in small and large cages of methane + propane mixed gas hydrates.

    Science.gov (United States)

    Sugahara, Takeshi; Kobayashi, Yusuke; Tani, Atsushi; Inoue, Tatsuya; Ohgaki, Kazunari

    2012-03-15

    To investigate the molecular interaction between guest species inside of the small and large cages of methane + propane mixed gas hydrates, thermal stabilities of the methyl radical (possibly induced in small cages) and the normal propyl and isopropyl radicals (induced in large cages) were investigated by means of electron spin resonance measurements. The increase of the total amount of the normal propyl and isopropyl radicals reveals that the methyl radical in the small cage withdraws one hydrogen atom from the propane molecule enclathrated in the adjacent large cage of the structure-II hydrate. A guest species in a hydrate cage has the ability to interact closely with the other one in the adjacent cages. The clathrate hydrate may be utilized as a possible nanoscale reaction field.

  6. Use of cage molecules for cleansing and chemical analysis; Utilisations de molecules cages pour la depollution et l'analyse chimique

    Energy Technology Data Exchange (ETDEWEB)

    Janus, L.

    2003-06-15

    Cage molecules are capable to include a large variety of compounds, and to release them without any modification. This 'host'-'guest' or 'receptor'-'substrate' association concept is commonly encountered in the biological domains, and thus cage molecules can imitate a natural process. In this work 4 types of cage molecules have been used: beta-cyclo-dextrin and two of its derivatives, and tetra-pyrazole macrocycles. Polymer supports carrying these different molecules have been elaborated by different ways (grafting, polymerization, coating of a pre-existing mineral support) and have been used for two types of applications: cleansing and chiral recognition. The targeted pollutants are the toxic aromatic compounds and the heavy metals. The chiral recognition is performed by capillary electrophoresis and high-performance liquid chromatography techniques. (J.S.)

  7. Courses of Action to Optimize Heavy Bearings Cages

    Science.gov (United States)

    Szekely, V. G.

    2016-11-01

    The global expansion in the industrial, economically and technological context determines the need to develop products, technologies, processes and methods which ensure increased performance, lower manufacturing costs and synchronization of the main costs reported to the elementary values which correspond to utilization”. The development trend of the heavy bearing industry and the wide use of bearings determines the necessity of choosing the most appropriate material for a given application in order to meet the cumulative requirements of durability, reliability, strength, etc. Evaluation of commonly known or new materials represents a fundamental criterion, in order to choose the materials based on the cost, machinability and the technological process. In order to ensure the most effective basis for the decision, regarding the heavy bearing cage, in the first stage the functions of the product are established and in a further step a comparative analysis of the materials is made in order to establish the best materials which satisfy the product functions. The decision for selecting the most appropriate material is based largely on the overlapping of the material costs and manufacturing process during which the half-finished material becomes a finished product. The study is orientated towards a creative approach, especially towards innovation and reengineering by using specific techniques and methods applied in inventics. The main target is to find new efficient and reliable constructive and/or technological solutions which are consistent with the concept of sustainable development.

  8. Structure and assembly of scalable porous protein cages

    Science.gov (United States)

    Sasaki, Eita; Böhringer, Daniel; van de Waterbeemd, Michiel; Leibundgut, Marc; Zschoche, Reinhard; Heck, Albert J. R.; Ban, Nenad; Hilvert, Donald

    2017-03-01

    Proteins that self-assemble into regular shell-like polyhedra are useful, both in nature and in the laboratory, as molecular containers. Here we describe cryo-electron microscopy (EM) structures of two versatile encapsulation systems that exploit engineered electrostatic interactions for cargo loading. We show that increasing the number of negative charges on the lumenal surface of lumazine synthase, a protein that naturally assembles into a ~1-MDa dodecahedron composed of 12 pentamers, induces stepwise expansion of the native protein shell, giving rise to thermostable ~3-MDa and ~6-MDa assemblies containing 180 and 360 subunits, respectively. Remarkably, these expanded particles assume unprecedented tetrahedrally and icosahedrally symmetric structures constructed entirely from pentameric units. Large keyhole-shaped pores in the shell, not present in the wild-type capsid, enable diffusion-limited encapsulation of complementarily charged guests. The structures of these supercharged assemblies demonstrate how programmed electrostatic effects can be effectively harnessed to tailor the architecture and properties of protein cages.

  9. Four-dimensional multi-site photolysis of caged neurotransmitters

    Directory of Open Access Journals (Sweden)

    Mary Ann eGo

    2013-12-01

    Full Text Available Neurons receive thousands of synaptic inputs that are distributed in space and time. The systematic study of how neurons process these inputs requires a technique to stimulate multiple yet highly targeted points of interest along the neuron's dendritic tree. Three-dimensional multi-focal patterns produced via holographic projection combined with two-photon photolysis of caged compounds can provide for highly localized release of neurotransmitters within each diffraction-limited focus, and in this way emulate simultaneous synaptic inputs to the neuron. However, this technique so far cannot achieve time-dependent stimulation patterns due to fundamental limitations of the hologram-encoding device and other factors that affect the consistency of controlled synaptic stimulation. Here, we report an advanced technique that enables the design and application of arbitrary spatio-temporal photostimulation patterns that resemble physiological synaptic inputs. By combining holographic projection with a programmable high-speed light-switching array, we have overcome temporal limitations with holographic projection, allowing us to mimic distributed activation of synaptic inputs leading to action potential generation. Our experiments uniquely demonstrate multi-site two-photon glutamate uncaging in three dimensions with submillisecond temporal resolution. Implementing this approach opens up new prospects for studying neuronal synaptic integration in four dimensions.

  10. Designing and defining dynamic protein cage nanoassemblies in solution.

    Science.gov (United States)

    Lai, Yen-Ting; Hura, Greg L; Dyer, Kevin N; Tang, Henry Y H; Tainer, John A; Yeates, Todd O

    2016-12-01

    Central challenges in the design of large and dynamic macromolecular assemblies for synthetic biology lie in developing effective methods for testing design strategies and their outcomes, including comprehensive assessments of solution behavior. We created and validated an advanced design of a 600-kDa protein homododecamer that self-assembles into a symmetric tetrahedral cage. The monomeric unit is composed of a trimerizing apex-forming domain genetically linked to an edge-forming dimerizing domain. Enhancing the crystallographic results, high-throughput small-angle x-ray scattering (SAXS) comprehensively contrasted our modifications under diverse solution conditions. To generate a phase diagram associating structure and assembly, we developed force plots that measure dissimilarity among multiple SAXS data sets. These new tools, which provided effective feedback on experimental constructs relative to design, have general applicability in analyzing the solution behavior of heterogeneous nanosystems and have been made available as a web-based application. Specifically, our results probed the influence of solution conditions and symmetry on stability and structural adaptability, identifying the dimeric interface as the weak point in the assembly. Force plots comparing SAXS data sets further reveal more complex and controllable behavior in solution than captured by our crystal structures. These methods for objectively and comprehensively comparing SAXS profiles for systems critically affected by solvent conditions and structural heterogeneity provide an enabling technology for advancing the design and bioengineering of nanoscale biological materials.

  11. Protein cages, rings and tubes: useful components of future nanodevices?

    Directory of Open Access Journals (Sweden)

    Jonathan G Heddle

    2008-11-01

    Full Text Available Jonathan G HeddleGlobal Edge Institute, Tokyo Institute of Technology, Nagatsuda, Midori-ku, Yokohama Kanagawa, JapanAbstract: There is a great deal of interest in the possibility that complex nanoscale devices can be designed and engineered. Such devices will lead to the development of new materials, electronics and smart drugs. Producing complex nanoscale devices, however will present many challenges and the components of such devices will require a number of special features. Devices will be engineered to incorporate desired functionalities but, because of the difficulties of controlling matter precisely at the nanoscale with current technology, the nanodevice components must self-assemble. In addition, nanocomponents that are to have wide applicability in various devices must have enough flexibility to integrate into a large number of potentially very different environments. These challenges are daunting and complex, and artificial nanodevices have not yet been constructed. However, the existence of nanomachines in nature in the form of proteins (eg, enzymes suggests that they will be possible to produce. As the material from which nature’s nanomachines are made, proteins seem ideal to form the basis of engineered components of such nanodevices. Initially, engineering projects may focus on building blocks such as rings, cages and tubes, examples of which exist in nature and may act as a useful start point for modification and further development. This review focuses on the recent research and possible future development of such protein building blocks.Keywords: bionanotechnology, protein engineering, nanomachine, building-blocks, synthetic biology

  12. Generalized Analytical Solutions for Nonlinear Positive-Negative Index Couplers

    Directory of Open Access Journals (Sweden)

    Zh. Kudyshev

    2012-01-01

    Full Text Available We find and analyze a generalized analytical solution for nonlinear wave propagation in waveguide couplers with opposite signs of the linear refractive index, nonzero phase mismatch between the channels, and arbitrary nonlinear coefficients.

  13. Three-Dimensional Approaches to Assembling Negative Index Metamedia

    Science.gov (United States)

    2012-04-02

    California, the IPO Distinguished Inventor (1998), the 1998 Thomas Alva Edison Award for innovation in emerging technology, the 1999 Materials Research...Near-field focusing plates and their design,” IEEE Trans. Antennas Propag. 56. 3159-3165 (2008). [5] A. Grbic, R. Merlin, E. M. Thomas and M. F...assembled InAs quantum dots on GaAs," Appl. Phys. Lett. 98, 021903 (2011). 72. A. Grbic, R. Merlin, E. M. Thomas and M. F. Imani, "Near-Field Plates

  14. Self-Assembled Soft Optical Negative Index Materials

    Science.gov (United States)

    2008-08-05

    Nanorods by Lyotropic Chromonic Materials’, Langmuir, 24 (2008), 13833-37. [15]. A. B. Golovin , and O. D. Lavrentovich, ’Electrically...Reconfigurable Optical Metamaterial Based on Colloidal Dispersion of Metal Nanorods in Dielectric Fluid’, Applied Physics Letters, 95 (2009) [16]. A. B. Golovin ...of Metal Nano-Rods in Dielectric Fluids’, Liquid Crystals Xiv, 7775 (2010) [17]. A. B. Golovin , J. Xiang, H. S. Park, L. Tortora, Y. A. Nastishin

  15. Compact wavelength demultiplexing using focusing negative index photonic crystal superprisms.

    Science.gov (United States)

    Momeni, Babak; Huang, Jiandong; Soltani, Mohammad; Askari, Murtaza; Mohammadi, Saeed; Rakhshandehroo, Mohammad; Adibi, Ali

    2006-03-20

    Here, we demonstrate a compact photonic crystal wavelength demultiplexing device based on a diffraction compensation scheme with two orders of magnitude performance improvement over the conventional superprism structures reported to date. We show that the main problems of the conventional superprism-based wavelength demultiplexing devices can be overcome by combining the superprism effect with two other main properties of photonic crystals, i.e., negative diffraction and negative refraction. Here, a 4-channel optical demultiplexer with a channel spacing of 8 nm and cross-talk level of better than -6.5 dB is experimentally demonstrated using a 4500 microm(2) photonic crystal region.

  16. Structure of Coatomer Cage Proteins and the Relationship among COPI, COPII, and Clathrin Vesicle Coats

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Changwook; Goldberg, Jonathan (MSKCC)

    2010-09-13

    COPI-coated vesicles form at the Golgi apparatus from two cytosolic components, ARF G protein and coatomer, a heptameric complex that can polymerize into a cage to deform the membrane into a bud. Although coatomer shares a common evolutionary origin with COPII and clathrin vesicle coat proteins, the architectural relationship among the three cages is unclear. Strikingly, the {alpha}{beta}-COP core of coatomer crystallizes as a triskelion in which three copies of a {beta}-COP {beta}-propeller domain converge through their axial ends. We infer that the trimer constitutes the vertex of the COPI cage. Our model proposes that the COPI cage is intermediate in design between COPII and clathrin: COPI shares with clathrin an arrangement of three curved {alpha}-solenoid legs radiating from a common center, and COPI shares with COPII highly similar vertex interactions involving the axial ends of {beta}-propeller domains.

  17. Direct gravimetric sensing of GBL by a molecular recognition process in organic cage compounds.

    Science.gov (United States)

    Brutschy, Malte; Schneider, Markus W; Mastalerz, Michael; Waldvogel, Siegfried R

    2013-09-28

    Organic cages were identified as highly potent affinity materials for the tracing of γ-butyrolactone. The selectivity over ethanol and water is based on the interior functional groups which allow preferential hydrogen bonding to the target analyte.

  18. STRENGTH AND DUCTILITY OF CONCRETE CYLINDERS REINFORCED WITH PREFABRICATED STEEL CAGE

    Directory of Open Access Journals (Sweden)

    CHITHRA R

    2011-09-01

    Full Text Available The article presents the results of an experimental and analytical study on behaviour of concrete cylinders confined with prefabricated cage. Totally 75 cylinders of 150mm diameter and 300mm in high confined by prefabricated cage are tested under uniaxial compression loads to obtain the stress strain curves of the cylinders. Test variables include thickness of cage, centre to centre spacing of ties and compressive strength of concrete. Equations to predict the ultimate compressive strength and strain at peak load were developed. A comparison between the experimental results and those of analytical results indicate that the proposed model provides satisfactory predictions of ultimate compressive strength. The study shows that the Mander et al’s model underestimate the strength of concrete confined by prefabricated cage.

  19. Anterior cervical discectomy with or without fusion with ray titanium cage: a prospective randomized clinical study

    DEFF Research Database (Denmark)

    Hauerberg, J.; Kosteljanetz, M.; Bøge-Rasmussen, Torben;

    2008-01-01

    STUDY DESIGN: A prospective randomized clinical study. OBJECTIVE: To compare 2 surgical methods in the treatment of cervical radiculopathy caused by hard or soft disc herniation; namely, simple discectomy versus discectomy with an additional interbody fusion with a Ray titanium cage. SUMMARY...... by fusion with a Ray titanium cage (40 patients) or to discectomy alone (46 patients). Clinical and radiologic follow-up was performed 3, 12, and 24 months after surgery. RESULTS: There was no statistically significant difference between the 2 groups concerning self-reported satisfaction or severity of pain...... in the neck and arm. Two years after the operation, 86.1% of the patients treated with cage stated a good outcome versus 76.7% in the discectomy group (P = 0.44). The rate of fusion was 83.3% in the cage group versus 81.0% in the discectomy group (P = 0.30). Furthermore, after 2 years, also the rates of new...

  20. A Cobalt Supramolecular Triple-Stranded Helicate-based Discrete Molecular Cage

    Science.gov (United States)

    Mai, Hien Duy; Kang, Philjae; Kim, Jin Kyung; Yoo, Hyojong

    2017-01-01

    We report a strategy to achieve a discrete cage molecule featuring a high level of structural hierarchy through a multiple-assembly process. A cobalt (Co) supramolecular triple-stranded helicate (Co-TSH)-based discrete molecular cage (1) is successfully synthesized and fully characterized. The solid-state structure of 1 shows that it is composed of six triple-stranded helicates interconnected by four linking cobalt species. This is an unusual example of a highly symmetric cage architecture resulting from the coordination-driven assembly of metallosupramolecular modules. The molecular cage 1 shows much higher CO2 uptake properties and selectivity compared with the separate supramolecular modules (Co-TSH, complex 2) and other molecular platforms. PMID:28262690

  1. The design of a cervical vertebra titanium plate-interbody fusion cage

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Objective: To study the biomechanical feature of a newly designed cervical vertebra internal fixation device and its clinical applications Methods: Some functional spinal units were fixed respectively with titanium plate, fusion cage and new device designed by ourselves, then a controlled biomechanical study including flexion, extension, torsion and lateral bending was performed and the results were analyzed. Results: As to the mechanical performance, fusion cage showed poor performance in extension test and so did the titanium plate in the distortion test. However, the new device showed good performance in every test. Conclusion: Both simple titanium plate fixation and simple fusion cage fixation have biomechanical defaults, but they are complementary. The titanium plate-interbody fusion cage avoids the defaults and has specific advantages.

  2. Unprecedented formation of polycyclic diazadiborepine derivatives through cage deboronation of m-carborane.

    Science.gov (United States)

    Harmgarth, Nicole; Hrib, Cristian G; Lorenz, Volker; Hilfert, Liane; Edelmann, Frank T

    2014-11-11

    An unprecedented deboronation reaction of icosahedral carboranes is described, in which a BH group of m-carborane is detached from the cage and incorporated into an unusual nido-carborane-anellated diazadiborepine ring system.

  3. Food consumption and food exchange of caged honey bees using a radioactive labelled sugar solution

    Science.gov (United States)

    Libor, Anika; Kupelwieser, Vera; Crailsheim, Karl

    2017-01-01

    We measured the distribution of sugar solution within groups of caged honey bees (Apis mellifera) under standard in vitro laboratory conditions using 14C polyethylene glycol as a radioactive marker to analyze ingestion by individual bees after group feeding. We studied the impact of different experimental setups by varying the number of bees, age of bees, origin of bees, duration of experiment, the amount of available diet, and the influence of the neurotoxic pesticide imidacloprid in the diet on the feeding and food sharing behavior (trophallaxis). Sugar solution was non-uniformly distributed in bees in 36 out of 135 cages. As a measure of the extent to which the sugar diet was equally distributed between caged bees, we calculated the (inner 80%) intake ratio by dividing the intake of the 90th percentile bee by the intake of the 10th percentile bee. This intake ratio ranged from 1.3 to 94.8 in 133 individual cages, further supporting a non-uniform distribution of food among caged bees. We can expect a cage with 10 or 30 bees containing one bee that ingests, on average, the 8.8-fold of the bee in the same cage ingesting the smallest quantity of food. Inner 80% intake ratios were lower in experiments with a permanent or chronic offering of labelled sugar solution compared to temporary or acute feedings. After pooling the data of replicates to achieve a higher statistical power we compared different experimental setups. We found that uniform food distribution is best approached with 10 newly emerged bees per cage, which originate from a brood comb from a single colony. We also investigated the trophallaxis between caged honey bees which originally consumed the diet and newly added bees. Color marked bees were starved and added to the cages in a ratio of 10:5 or 20:20 after the initial set of bees consumed all the labelled sugar solution. The distribution of the labelled sugar solution by trophallaxis within 48 hours to added bees was 25% (10:5) or 45% (20:20) of the

  4. Synthesis of Silsesquioxane Cages from Phenyl-cis-tetrol,1,3-Divinyltetraethoxydisiloxane and Cyclopentyl Resins

    Institute of Scientific and Technical Information of China (English)

    LIU Zhi-hua; Alan R. Bassindale; Peter G. Taylor

    2004-01-01

    The synthesis of Ts, T10 and T12 silsesquioxane cages from a range of starting materials: phenyl-cistetrol, 1,3-divinyltetraethoxydisiloxane and cyclopentyl T resins by using tetra n-butylammonium fluoride (TBAF) as the catalyst is described in this paper. The reaction yields obtained via the current route are better compared to those via the literature routes. Some of the cage compounds have been characterized by X-ray crystallography.

  5. Extended Durability of a Cloth-Covered Star-Edwards Caged Ball Prosthesis in Aortic Position

    Directory of Open Access Journals (Sweden)

    Yusuf Ata

    2009-01-01

    Full Text Available The Starr-Edwards caged ball valve is one of the oldest cardiac valve prosthesis and was widely used all around the world in the past decades. Despite the long-term results that have been reported there are only a few cases reported that exceed 30 years of durability. Here in, we report a 53-year-old patient with a well-functioning 35-year-old aortic Starr-Edwards caged ball prosthesis.

  6. Mouse housing system using pressurized cages intraventilated by direct-current microfans.

    Science.gov (United States)

    Martinewski, Alexandre; Correia, Caio S C; de Souza, Nívea L; Merusse, José L B

    2012-03-01

    We performed the initial assessment of an alternative pressurized intraventilated (PIV) caging system for laboratory mice that uses direct-current microfans to achieve cage pressurization and ventilation. Twenty-nine pairs of female SPF BALB/c mice were used, with 19 experimental pairs kept in PIV cages and 10 control pairs kept in regular filter-top (FT) cages. Both groups were housed in a standard housing room with a conventional atmospheric control system. For both systems, intracage temperatures were in equilibrium with ambient room temperature. PIV cages showed a significant difference in pressure between days 1 and 8. Air speed (and consequently airflow rate) and the number of air changes hourly in the PIV cages showed decreasing trends. In both systems, ammonia concentrations increased with time, with significant differences between groups starting on day 1. Overall, the data revealed that intracage pressurization and ventilation by using microfans is a simple, reliable system, with low cost, maintenance requirements, and incidence of failures. Further experiments are needed to determine the potential influence of this system on the reproductive performance and pulmonary integrity in mice.

  7. Effects of Metabolic Cage Housing on Rat Behavior and Performance in the Social Interaction Test.

    Science.gov (United States)

    Whittaker, Alexandra L; Lymn, Kerry A; Howarth, Gordon S

    2016-01-01

    Although the metabolic cage is commonly used for housing nonhuman animals in the laboratory, it has been recognized as constituting a unique stressor. Such an environment would be expected to affect behavioral change in animals housed therein. However, few studies have specifically addressed the nature or magnitude of this change. The current study sought to characterize the behavioral time budget of rats in metabolic cage housing in comparison to that of individually housed animals in standard open-top cages. Rats in metabolic cages spent less time moving, manipulating enrichment, and carrying out rearing behaviors, and there was a corresponding shift toward inactivity. In an applied Social Interaction Test, behavioral scoring implied that metabolic cage housing had an anxiogenic effect. In conclusion, metabolic cage housing produces measurable effects on spontaneous and evoked behavior in rats in the laboratory. These behavioral changes may lead to a negative emotional state in these animals, which could have negative welfare consequences. Further research is needed to quantify the existence and magnitude of such an effect on rat well being.

  8. Atomistic simulations of CO2 and N2 within cage-type silica zeolites.

    Science.gov (United States)

    Madison, Lindsey; Heitzer, Henry; Russell, Colin; Kohen, Daniela

    2011-03-01

    The behavior of CO(2) and N(2), both as single components and as binary mixtures, in two cage-type silica zeolites was studied using atomistic simulations. The zeolites considered, ITQ-3 and paradigm cage-type zeolite ZK4 (the all-silica analog of LTA), were chosen so that the principles illustrated can be generalized to other adsorbent/adsorbate systems with similar topology and types of interactions. N(2) was chosen both because of the potential uses of N(2)/CO(2) separations and because it differs from CO(2) most significantly in the magnitude of its Coulombic interactions with zeolites. Despite similarities between N(2) and CO(2) diffusion in other materials, we show here that the diffusion of CO(2) within cage-type zeolites is dominated by an energy barrier to diffusion located at the entrance to the narrow channels connecting larger cages. This barrier originates in Coulombic interactions between zeolites and CO(2)'s quadrupole and results in well-defined orientations for the diffusing molecules. Furthermore, CO(2)'s favorable electrostatic interactions with the zeolite framework result in preferential binding in the windows between cages. N(2)'s behavior, in contrast, is more consistent with that of molecules previously studied. Our analysis suggests that CO(2)'s behavior might be common for adsorbates with quadrupoles that interact strongly with a material that has narrow windows between cages.

  9. Effect of lipopolysaccharide on sickness behaviour in hens kept in cage and free range environments.

    Science.gov (United States)

    Gregory, N G; Payne, S R; Devine, C D; Cook, C J

    2009-08-01

    The aim of this study was to assess whether environmental enrichment and environmental conditions can influence the expression of sickness behaviour. The behaviour in response to injection of lipopolysaccharide or saline was examined in a total of 96 62-weeks old hatchmate hens kept in a free range or cage environment. There were eight experimental treatments, each with 12 birds. Half the birds were sourced from a commercial cage layer unit (C/-) and half from a commercial free range unit (FR/-). After intraperitoneal injection with either lipopolysaccharide or saline (as a control), the hens were placed in either a cage (-/C) or free range (-/FR) environment. Lipopolysaccharide caused greater suppression of activity in free range (FR/FR) than in caged hens, including less walking (53% reduction), roosting (-86%) and preening (-60%) (pcaged birds released into free range, nor in free range birds introduced to cages, suggesting that both the presence of and the familiarity with an environment affected sickness behaviour patterns. Increased sleeping was the most consistent response (+147%; pcaged hens, and this may make it more difficult to recognise disease expression in the caged environment.

  10. Titanium Alloy Cage Implantation for the Treatment of Ischemic Necrosis of Femoral Head in Dogs

    Institute of Scientific and Technical Information of China (English)

    Ruiying WANG; Yan GAO; Shuhua YANG; Cao YANG

    2008-01-01

    To study the effect of titanium alloy cage on the treatment of the ischemic necrosis of femoral head in dog, the model of the ischemic necrosis of femoral head was made with the liquid nitrogon in 15 hybrid adult dogs. The titanium alloy cage made of a hollow cylinder was driven into the subchondral bone of necrotic femoral head via central channel. The dogs were divided into 3 groups, each group was sacrificed 3, 6, 12 weeks after the operation respectively. No collapse of femoral head was observed after the operation. The position of the cages was good on radiograph. Microscopically, the cancellous bone of necrotic femoral head rebuilt gradually and grew into cage. After 12 weeks of creeping substitution, the cancellous bone filled up the hollow cavity and holes of the cages. It is concluded that the titanium alloy cage can provide structural support for the subchondral bone and prevent collapse and can be used for the treatment of the ischemic necrosis of femoral head.

  11. Environmental impact of sea bass cage farming in the north Adriatic Sea

    Directory of Open Access Journals (Sweden)

    Domenico Lanari

    2010-01-01

    Full Text Available The main objective of the research was to reduce the organic and nutrient load under the net pen fish farms. An exper- iment was conducted to study the effects of artificial barriers fixed under a set of sea cages in order to reduce the envi- ronmental impact. The artificial barriers were made of four submerged galvanized steel pipes coated with plastic and placed on the sea floor (10 m depth in the Trieste gulf. The experimental design was as follows: control (C, cages with barriers (B, cages without barriers (WB. Measurements were taken on the surface as well as at 4 and 8m of depth. The trial lasted from the end of June 2000 to December 2001. Water quality parameters were not significantly influenced by the fish cages. Surface samples were characterised by lower levels of salinity and higher levels of oxygen and nitrate compared to those taken at 4 and 8 m. The artificial barriers favoured the establishment of a rich epiphytic fauna that took advantage of the presence of organic matter derived from fish cages. The two species Nucula nucleusand Neanthes caudataand the total bacterial counts were identified as potential indicators of pollution under the fish cage farms.

  12. DFT-based inhibitor and promoter selection criteria for pentagonal dodecahedron methane hydrate cage

    Indian Academy of Sciences (India)

    Snehanshu Pal; T K Kundu

    2013-09-01

    Density functional theory (DFT)-based simulations have been performed to provide electronic structure property correlation based reasoning for conceptualizing the effect of encapsulated methane molecule on the formation of methane hydrate cages, the role of methanol and ethylene glycol as inhibitor and the role of tetra-hydro-furan (THF) and cyclopentane as promoter of methane hydrate. Geometry optimization of 512 cage, 51262 cage and 51264 cage with and without encapsulated methane and the cluster of 512 cage with ethylene glycol, methanol, cyclopentane have been performed by density functional theory using B97X-D/6-31++G(d,p) method. Methane hydrate formation inhibition by methanol and ethylene glycol as well as methane hydrate stabilization by cyclopentane and tetrahydrofuran are critically analysed based on the interaction energy, free energy change, dipole moment and infrared frequency calculation. Calculation of free energy change for formation of methane hydrate with/without reagents at various temperature and pressure using optimized structure is reported here. It is observed that hydrogen bond between water molecules of clathrate 512 cages become stronger in the presence of cyclopentane and tetrahydrofuran but weaker/broken in the presence of ethylene glycol and methanol. Simulated results correspond well with experimental findings and can be useful for designing new inhibitor and promoter molecules for gas hydrate formation.

  13. Provision Of Carbon Nanotube Bucky Paper Cages For Immune Shielding Of Cells, Tissues, and Medical Devices

    Science.gov (United States)

    Loftus, David J. (Inventor)

    2006-01-01

    System and method for enclosing cells and/or tissue, for purposes of growth, cell differentiation, suppression of cell differentiation, biological processing and/or transplantation of cells and tissues (biological inserts), and for secretion, sensing and monitoring of selected chemical substances and activation of gene expression of biological inserts implanted into a human body. Selected cells and/or tissue are enveloped in a "cage" that is primarily carbon nanotube Bucky paper, with a selected thickness and porosity. Optionally, selected functional groups, proteins and/or peptides are attached to the carbon nanotube cage, or included within the cage, to enhance the growth and/or differentiation of the cells and/or tissue, to select for certain cellular sub-populations, to optimize certain functions of the cells and/or tissue and/or to optimize the passage of chemicals across the cage surface(s). A cage system is also used as an immuns shield and to control operation of a nano-device or macroscopic device, located within the cage, to provide or transform a selected chemical and/or a selected signal.

  14. Model of a generator end-winding cage; Modelisation d`une cage de developpantes d`alternateur

    Energy Technology Data Exchange (ETDEWEB)

    Leger, A.C.; Fanton, J.P.; Davies, C.

    1994-09-01

    This document presents some studies concerning the vibratory characterization of particular structures called: generator end-winding cages. These structures are mainly made up of the endings of armature windings. The question of their good mechanical behaviour is of prime importance, since they are submitted to high electromagnetic efforts during the different electrical ratings encountered during operation. The designer (GEC-Alsthom) and the user (EDF) have both undertaken numerical calculations in order to characterize a given machine, in this case a 600 MW bipolar generator; it appeared interesting to compare such calculations. The models realized respectively by GEC-Alsthom and EDF make use of different techniques and hypotheses. GEC-Alsthom represents the sets of rods and spacers by plates, which properties are determined by a pre-processor. The model is simplified to take into account the existing symmetries. It takes profit of previous experience and aims at a fast utilisation. The EDF model tends to allow a further comprehensive calculation, form the electromagnetic efforts to the determination of local stresses. The whole set of the constituting elements of the structure is modelled by beams, which leads to an important size for the model (21 000 degrees of freedom). The validation performed on the two models has been focused on the comparison between respective results and also with experimental results. Each model provides values for the first eigenfrequencies and the associated modes shapes. (authors). 3 refs., 3 figs., 2 tabs.

  15. Handling of bulk solids theory and practice

    CERN Document Server

    Shamlou, P A

    1990-01-01

    Handling of Bulk Solids provides a comprehensive discussion of the field of solids flow and handling in the process industries. Presentation of the subject follows classical lines of separate discussions for each topic, so each chapter is self-contained and can be read on its own. Topics discussed include bulk solids flow and handling properties; pressure profiles in bulk solids storage vessels; the design of storage silos for reliable discharge of bulk materials; gravity flow of particulate materials from storage vessels; pneumatic transportation of bulk solids; and the hazards of solid-mater

  16. Nanofluidics, from bulk to interfaces.

    Science.gov (United States)

    Bocquet, Lydéric; Charlaix, Elisabeth

    2010-03-01

    Nanofluidics has emerged recently in the footsteps of microfluidics, following the quest for scale reduction inherent to nanotechnologies. By definition, nanofluidics explores transport phenomena of fluids at nanometer scales. Why is the nanometer scale specific? What fluid properties are probed at nanometric scales? In other words, why does 'nanofluidics' deserve its own brand name? In this critical review, we will explore the vast manifold of length scales emerging for fluid behavior at the nanoscale, as well as the associated mechanisms and corresponding applications. We will in particular explore the interplay between bulk and interface phenomena. The limit of validity of the continuum approaches will be discussed, as well as the numerous surface induced effects occurring at these scales, from hydrodynamic slippage to the various electro-kinetic phenomena originating from the couplings between hydrodynamics and electrostatics. An enlightening analogy between ion transport in nanochannels and transport in doped semi-conductors will be discussed (156 references).

  17. New fermions in the bulk

    CERN Document Server

    de Brito, K P S

    2016-01-01

    Spinor fields on 5-dimensional Lorentzian manifolds are classified, according to the geometric Fierz identities that involve their bilinear covariants. Based upon this classification that generalises the celebrated 4-dimensional Lounesto classification of spinor fields, new non-trivial classes of 5-dimensional spinor fields are, hence, found, with important potential applications regarding bulk fermions and their subsequent localisation on brane-worlds. In addition, quaternionic bilinear covariants are used to derive the quaternionic spin density, through the truncated exterior bundle. In order to accomplish a realisation of these new spinors, a Killing vector field is constructed on the horizon of 5-dimensional Kerr black holes. This Killing vector field is shown to reach the time-like Killing vector field at the spatial infinity, through a current 1-form density, constructed with the derived new spinor fields. The current density is, moreover, expressed as the f\\"unfbein components, assuming a condensed for...

  18. New fermions in the bulk

    Science.gov (United States)

    de Brito, K. P. S.; da Rocha, Roldão

    2016-10-01

    The spinor fields on 5-dimensional Lorentzian manifolds are classified according to the geometric Fierz identities, which involve their bilinear covariants. Based upon this classification, which generalises the celebrated 4-dimensional Lounesto classification of spinor fields, new non-trivial classes of 5-dimensional spinor fields are hence found, with important potential applications regarding bulk fermions and their subsequent localisation on brane-worlds. In addition, quaternionic bilinear covariants are used to derive the quaternionic spin density through the truncated exterior bundle. In order to accomplish the realisation of these new spinors, a Killing vector field is constructed on the horizon of a 5-dimensional Kerr black hole. This Killing vector field is shown to reach the time-like Killing vector field at spatial infinity through a current 1-form density, constructed with the new derived spinor fields. The current density is, moreover, expressed as the fünfbein component, assuming a condensed form.

  19. Effects of wire-bottom caging on heart rate, activity and body temperature in telemetry-implanted rats.

    Science.gov (United States)

    Giral, Marta; García-Olmo, Dolores C; Kramer, Klaas

    2011-10-01

    Some experimental procedures are associated with placement of animals in wire-bottom cages. The goal of this study was to evaluate stress-related physiological parameters (heart rate [HR], body temperature [BT], locomotor activity [LA], body weight [BW] and food consumption) in rats under two housing conditions, namely in wire-bottom cages and in bedding-bottom cages. Telemetry devices were surgically implanted in male Sprague-Dawley rats. HR, BT and LA were recorded at 5 min intervals. Analysis under each housing condition was performed from 16:00 to 08:00 h of the following day (4 h light, 12 h dark). During almost all of the light phase, the HR of rats housed in wire-bottom cages remained high (371 ± 35 bpm; mean ± SD; n = 6) and was significantly different from that of rats housed in bedding-bottom cages (340 ± 29 bpm; n = 6; P wire-bottom cages, BT tended to fluctuate more widely during the dark phase. LA decreased when animals were housed in wire-bottom cages, in particular during the dark phase. Moreover, there was a significant difference with respect to the gain in BW: BW of rats housed in bedding-bottom cages increased 12 ± 2 g, whereas that of rats in wire-bottom cages decreased by 2 ± 3 g (P wire-bottom cages overnight leads to immediate alterations of HR, BW and LA, which might be related to a stress response.

  20. Analysis and interpretation of the model of a Faraday cage for electromagnetic compatibility testing

    Directory of Open Access Journals (Sweden)

    Nenad V. Munić

    2014-02-01

    Full Text Available In order to improve the work of the Laboratory for Electromagnetic Compatibility Testing in the Technical Test Center (TTC, we investigated the influence of the Faraday cage on measurement results. The primary goal of this study is the simulation of the fields in the cage, especially around resonant frequencies, in order to be able to predict results of measurements of devices under test in the anechoic chamber or in any other environment. We developed simulation (computer models of the cage step by step, by using the Wipl-D program and by comparing the numerical results with measurements as well as by resolving difficulties due to the complex structure and imperfections of the cage. The subject of this paper is to present these simulation models and the corresponding results of the computations and measurements. Construction of the cage The cage is made of steel plates with the dimensions 1.25 m x 2.5 m. The base of the cage is a square; the footprint interior dimensions are 3.76 m x 3.76 m, and the height is 2.5 m. The cage ceiling is lowered by plasticized aluminum strips. The strips are loosely attached to the carriers which are screwed to the ceiling. The cage has four ventilation openings (two on the ceiling and two on one wall, made of honeycomb waveguide holes. In one corner of the cage, there is a single door with springs made of beryllium bronze. For frequencies of a few tens of MHz, the skin effect is fully developed in the cage walls. By measuring the input impedance of the wire line parallel to a wall of the cage, we calculated the surface losses of the cage plates. In addition, we used a magnetic probe to detect shield discontinuities. We generated a strong current at a frequency of 106 kHz outside the cage and measured the magnetic field inside the cage at the places of cage shield discontinuities. In this paper, we showed the influence of these places on the measurement results, especially on the qualitative and quantitative

  1. 快速笼式烟夹的研制与应用%Development and Application of Quick Cage Tobacco Clip

    Institute of Scientific and Technical Information of China (English)

    王卫峰; 张克勤; 李波; 李开和; 王五权; 陆华君; 赵宾; 邓明军; 卢燕回

    2013-01-01

      为解决当前烟叶夹持设备存在的不足,减轻劳动强度,研制了快速笼式烟夹,并对其进行了应用效果试验。结果表明,与传统挂竿烘烤相比,使用快速笼式烟夹可增加密集烤房装烟容量51%,能耗节约0.09元/kg干烟,节约用工34.5个/hm2,烤后烟叶颜色橘黄,成熟度好,评吸得分85.6分,烟叶外观质量得到改善。%The quick cage tobacco clip was developed to improve efficiency of tobacco leaf holding equipment and reduce labor intensity. Compared with the traditional leaf loading approach, the quick cage tobacco clip could increase capacity of bulk curing barn by 51%, reduce the energy consumption by 0.09 yuan/kg tobacco leaf, save labor cost by 34.5 md/ha, and improve appearance quality of cured leaves, with an average score of 85.6 for smoking test.

  2. Impact of sea waves on underwater fish-breeding cages

    Directory of Open Access Journals (Sweden)

    Pilyaev Sergey Ivanovich

    2014-02-01

    Full Text Available Cultivation of sea objects is of great importance while solving the problems of providing the constantly growing requirements of the national economy with sea products. Cultivation of sea objects uses special hydrobiotechnical constructions. As the practice showed, cultivation of seafood is commercially impossible without solving the questions of calculating and designing such constructions. In special literature these questions are poorly covered or not considered at all. In the article the results of theoretical and pilot studies of waves influence on hydrobiotechnical constructions is provided, in particular on underwater fish-breeding cages.This article offers the theoretical solution to the problem of determining the efforts of the ropes holding the fish tank under wave influences. In order to solve this problem, the equations of hard drives movements were set up and the differential equations of free oscillations of buzz were obtained.When determining the horizontal movements, the four different configurations of connections and the system motion directions in general are possible in case of waveoscillations. Next step is the solution of the differential equations and determination of natural oscillation frequency in the direction of the vertical axis. Defining efforts in the ropes from their own weight (static calculation is self-explanatory, it should be noted that accounting for the weighing influence of water on such structures does not have significant influence.Further the authors defined loading and efforts from the regular waves’ impacts.Modeling of the waves influence on submersible fish tank was carried by Fraud method. The studies were conducted with two models with large and small mesh. The signals of strain gauge sensors were registered by electronic measuring equipment.When comparing the theoretical and experimental data, satisfactory results have been obtained. It was determined that in order to improve the calculation

  3. Calcium Sulfoaluminate Sodalite (Ca 4 Al 6 O 12 SO 4 ) Crystal Structure Evaluation and Bulk Modulus Determination

    KAUST Repository

    Hargis, Craig W.

    2013-12-12

    The predominant phase of calcium sulfoaluminate cement, Ca 4(Al6O12)SO4, was investigated using high-pressure synchrotron X-ray diffraction from ambient pressure to 4.75 GPa. A critical review of the crystal structure of Ca4(Al 6O12)SO4 is presented. Rietveld refinements showed the orthorhombic crystal structure to best match the observed peak intensities and positions for pure Ca4(Al6O 12)SO4. The compressibility of Ca4(Al 6O12)SO4 was studied using cubic, orthorhombic, and tetragonal crystal structures due to the lack of consensus on the actual space group, and all three models provided similar results of 69(6) GPa. With its divalent cage ions, the bulk modulus of Ca4(Al6O 12)SO4 is higher than other sodalites with monovalent cage ions, such as Na8(AlSiO4)6Cl2 or Na8(AlSiO4)6(OH)2·H 2O. Likewise, comparing this study to previous ones shows the lattice compressibility of aluminate sodalites decreases with increasing size of the caged ions. Ca4(Al6O12)SO4 is more compressible than other cement clinker phases such as tricalcium aluminate and less compressible than hydrated cement phases such as ettringite and hemicarboaluminate. © 2013 The American Ceramic Society.

  4. Biomechanical evaluation of DTRAX® posterior cervical cage stabilization with and without lateral mass fixation

    Science.gov (United States)

    Voronov, Leonard I; Siemionow, Krzysztof B; Havey, Robert M; Carandang, Gerard; Patwardhan, Avinash G

    2016-01-01

    Introduction Lateral mass screw (LMS) fixation with plates or rods is the current standard procedure for posterior cervical fusion. Recently, implants placed between the facet joints have become available as an alternative to LMS or transfacet screws for patients with cervical spondylotic radiculopathy. The purpose of this study was to evaluate the biomechanical stability of the DTRAX® cervical cage for single- and two-level fusion and compare this to the stability achieved with LMS fixation with rods in a two-level construct. Methods Six cadaveric cervical spine (C3–C7) specimens were tested in flexion–extension, lateral bending, and axial rotation to ±1.5 Nm moment without preload (0 N) in the following conditions: 1) intact (C3–C7), 2) LMS and rods at C4–C5 and C5–C6, 3) removal of all rods (LMS retained) and placement of bilateral posterior cages at C5–C6, 4) bilateral posterior cages at C4–C5 and C5–C6 (without LMS and rods), and 5) C4–C5 and C5–C6 bilateral posterior cages at C4–C5 and C5–C6 with rods reinserted. Results Bilateral posterior cervical cages significantly reduced range of motion in all tested directions in both single- and multilevel constructs (P<0.05). Similar stability was achieved with bilateral posterior cages and LMS in a two-level construct: 0.6°±0.3° vs 1.2°±0.4° in flexion–extension (P=0.001), (5.0°±2.6° vs 3.1°±1.3°) in lateral bending (P=0.053), (1.3°±1.0° vs 2.2°±0.9°) in axial rotation (P=0.091) for posterior cages and LMS, respectively. Posterior cages, when placed as an adjunct to LMS, further reduced range of motion in a multilevel construct (P<0.05). Conclusion Bilateral posterior cages provide similar cervical segmental stability compared with a LMS and rod construct and may be an alternative surgical option for select patients. Furthermore, supplementation of a lateral mass construct with posterior cages increases cervical spine stability in single- and multilevel conditions. PMID

  5. Sea-cage aquaculture, sea lice, and declines of wild fish.

    Science.gov (United States)

    Frazer, L Neil

    2009-06-01

    A sea cage, sometimes referred to as a net pen, is an enclosure designed to prevent farm fish from escaping and to protect them from large predators, while allowing a free flow of water through the cage to carry away waste. Farm fish thus share water with wild fish, which enables transmission of parasites, such as sea lice, from wild to farm and farm to wild fishes. Sea lice epidemics, together with recently documented population-level declines of wild salmon in areas of sea-cage farming, are a reminder that sea-cage aquaculture is fundamentally different from terrestrial animal culture. The difference is that sea cages protect farm fish from the usual pathogen-control mechanisms of nature, such as predators, but not from the pathogens themselves. A sea cage thus becomes an unintended pathogen factory. Basic physical theory explains why sea-cage aquaculture causes sea lice on sympatric wild fish to increase and why increased lice burdens cause wild fish to decline, with extirpation as a real possibility. Theory is important to this issue because slow declines of wild fish can be difficult to detect amid large fluctuations from other causes. The important theoretical concepts are equilibrium, host-density effect, reservoir-host effect, and critical stocking level of farmed fish (stocking level at which lice proliferate on farm fish even if wild fish are not present to infect them). I explored these concepts and their implications without mathematics through examples from salmon farming. I also considered whether the lice-control techniques used by sea-cage farmers (medication and shortened grow-out times) are capable of protecting wild fish. Elementary probability showed that W ≈ W* - εF (where W is the abundance of wild fish, W* is the prefarm abundance, F is the abundance of farm fish, and ε is the ratio of lice per farm fish to lice per wild fish). Declines of wild fish can be reduced by short growing cycles for farm fish, medicating farm fish, and keeping

  6. Effect of cage type on the behaviour patterns of rabbit does at different physiological stages

    Directory of Open Access Journals (Sweden)

    Clara Alfonso-Carrillo

    2014-03-01

    Full Text Available Interest in commercially farmed rabbit welfare has increased in recent years. As a result, new alternativehousing systems have been developed, although they require evaluation in order to demonstrate their potential for improving welfare. The aim of this trial was to study the behavioural traits of rabbit does housed in 2 different types of cage (TC: conventional vs. alternative with an elevated platform, at different physiological stages (PS; lactation and gestation. Behavioural observations were carried out on 12 rabbit commercial does using continuous 24 h video recording. Independently of PS and TC, rabbit does spent most of their time on foot mats (on av. 57.7%. However, due to the use of platforms (on av. 23.0% of time, lactating does spent 36.6% less time on foot mats (P<0.001 and gestating does spent 27.0% less time on wire mesh (P<0.001 in alternative cages than in conventional cages. Alternative cages allowed for standing posture, but this behaviour was only observed in gestating does (on av. 4.6 times a day. Frequency of drinking was higher in conventional than in alternative cages (24.6 vs. 19.1 times a day; P<0.05. Gestating does housed in conventional cages reached the highest duration and frequency of interacting with neighbours (276 s/d and 4.6 times/d; P<0.05. The frequency of interacting with kits was lower in alternative than in conventional cages (2.4 vs. 8.6 times a day; P<0.01. Doe behaviour was influenced by the time of day, with less activity during the midday hours. During dark hours, rabbit does more frequently performed restless behaviour such as hyperactivity or nursing, matching the time at which rabbit does spent more time on the platform. The platform was frequently used by rabbit does, regardless of their physiological stage, and during late lactation phase, when mothers were not receptive to nursing, does housed in alternative cages used the platform as a mean to flee from kits trying to suckle

  7. Posterior lumbar inter-body fusion (PLIF) using autogenous bone and cage with pedicle screw instrumentation versus PLIF using cage with pedicle screw instrumentation in adult spondylolisthesis

    Institute of Scientific and Technical Information of China (English)

    Dou Yusheng; Hao Dingjun; Wen Shiming

    2005-01-01

    Objective: To compare the clinical outcomes of PLIF using autogenous bone and cage with pedicle screw fixation (group 2) and simple cage fusion with pedicle screw fixation (group 1) in adult spondylolisthesis.Methods: 27 patients with minimum follow-up of 24 months, treated by inter-body fusion with pedicle screw fixation were prospectively studied. Disc space height, degree of slippage and fusion rate had been compared before and after operation between the two groups. Results: After minimum 24 month's follow-up, there was no significant difference between the two groups in terms of the amount of blood loss, duration of hospital stay, back pain,radiating pain, fusion rate, or complication (P>0.05). however, there was a significant difference between the two groups in terms of disc space height and percentage of slippage (P<0.05). Conclusion: PLIF using autogenous bone and cage with pedicle screw fixation more beneifical to improve fusion rate and prevent long-term instabilities than simple cage fusion with pedicle screw fixation in adult spondylolisthesis.

  8. The fear levels after transport of hens from cages and a free-range system.

    Science.gov (United States)

    Scott, G B; Connell, B J; Lambe, N R

    1998-01-01

    All end-of-lay hens must be transported from the production site to the site for slaughter, usually by road. The acts of being crated and transported are likely to be novel and potentially frightening. Frightened birds can be put into tonic immobility (TI), an unlearned, catatonic state, the duration of which is positively related to the fear level of the birds. Ninety ISA Brown free-range birds (in three groups of 30) and 90 caged ISA Brown birds (in similar groups) were transported (one group from cages and free-range per day) on a journey of 68 km (74 min approximately). On their return, each of the birds was subjected to TI. Although no significant differences were recorded between free-range and caged birds after they were transported (P = 0.087), in the comparison between the same birds after 7 wk, without transport, a significant difference in fear levels was observed (P birds were less frightened than the caged birds. No significant difference was ever found in fear levels for caged birds from different tiers. Handling and transport on this relatively short journey was apparently equally frightening for caged and free-range birds. It cannot be assumed that just because fear levels differ between free-range and caged birds, this difference will be apparent for all novel stimuli. If all birds, at all tiers, receive the same amount of human contact during the production period, there is no reason to expect differences to occur in fear levels of birds from different tiers.

  9. Horizontal transmission of Salmonella Enteritidis in experimentally infected laying hens housed in conventional or enriched cages.

    Science.gov (United States)

    Gast, Richard K; Guraya, Rupa; Jones, Deana R; Anderson, Kenneth E

    2014-12-01

    The majority of human illnesses caused by Salmonella Enteritidis are attributed to contaminated eggs, and the prevalence of this pathogen in commercial laying flocks has been identified as a leading epidemiologic risk factor. Flock housing and management systems can affect opportunities for the introduction, transmission, and persistence of foodborne pathogens in poultry. The animal welfare implications of different types of housing for laying hens have been widely discussed in recent years, but the food safety consequences of these production systems remain incompletely understood. The present study assessed the effects of 2 different housing systems (conventional cages and colony cages enriched with perching and nesting areas) on the horizontal transmission of experimentally introduced Salmonella Enteritidis infection within groups of laying hens. In each of 2 trials, 136 hens were distributed among cages of both housing systems and approximately one-third of the hens in each cage were orally inoculated with doses of 10(8) cfu of Salmonella Enteritidis (phage type 13a in one trial and phage type 4 in the other). At regular intervals through 23 d postinoculation, cloacal swabs were collected from all hens (inoculated and uninoculated) and cultured for Salmonella Enteritidis. Horizontal contact transmission of infection was observed for both Salmonella Enteritidis strains, reaching peak prevalence values of 27.1% of uninoculated hens in conventional cages and 22.7% in enriched cages. However, no significant differences (P > 0.05) in the overall frequencies of horizontal Salmonella Enteritidis transmission were evident between the 2 types of housing. These results suggest that opportunities for Salmonella Enteritidis infection to spread horizontally throughout laying flocks may be similar in conventional and enriched cage-based production systems.

  10. Field cage studies and progressive evaluation of genetically-engineered mosquitoes.

    Directory of Open Access Journals (Sweden)

    Luca Facchinelli

    Full Text Available BACKGROUND: A genetically-engineered strain of the dengue mosquito vector Aedes aegypti, designated OX3604C, was evaluated in large outdoor cage trials for its potential to improve dengue prevention efforts by inducing population suppression. OX3604C is engineered with a repressible genetic construct that causes a female-specific flightless phenotype. Wild-type females that mate with homozygous OX3604C males will not produce reproductive female offspring. Weekly introductions of OX3604C males eliminated all three targeted Ae. aegypti populations after 10-20 weeks in a previous laboratory cage experiment. As part of the phased, progressive evaluation of this technology, we carried out an assessment in large outdoor field enclosures in dengue endemic southern Mexico. METHODOLOGY/PRINCIPAL FINDINGS: OX3604C males were introduced weekly into field cages containing stable target populations, initially at 10:1 ratios. Statistically significant target population decreases were detected in 4 of 5 treatment cages after 17 weeks, but none of the treatment populations were eliminated. Mating competitiveness experiments, carried out to explore the discrepancy between lab and field cage results revealed a maximum mating disadvantage of up 59.1% for OX3604C males, which accounted for a significant part of the 97% fitness cost predicted by a mathematical model to be necessary to produce the field cage results. CONCLUSIONS/SIGNIFICANCE: Our results indicate that OX3604C may not be effective in large-scale releases. A strain with the same transgene that is not encumbered by a large mating disadvantage, however, could have improved prospects for dengue prevention. Insights from large outdoor cage experiments may provide an important part of the progressive, stepwise evaluation of genetically-engineered mosquitoes.

  11. The effect of perch availability during pullet rearing and egg laying on the behavior of caged White Leghorn hens.

    Science.gov (United States)

    Hester, P Y; Garner, J P; Enneking, S A; Cheng, H W; Einstein, M E

    2014-10-01

    Enriched cages, compared with conventional cages, allow egg laying strains of chickens to meet some behavioral needs, including a high motivation to perch. The objective of this study was to determine if perch availability during rearing affected perch use as adults and if perch presence affected eating and drinking in caged White Leghorn hens. Chickens were assigned to 14 cages each with and without 2 round metal perches from hatch to 16.9 wk of age. At 17 wk of age, pullets were assigned to laying cages consisting of 1 of 4 treatments. Treatment 1 chickens never had access to perches (controls). Treatment 2 chickens only had access to 2 round metal perches during the laying phase (17 to 71 wk of age). Treatment 3 chickens only had access to 2 round perches during the pullet phase (0 to 16.9 wk of age). Treatment 4 chickens had access to the perches during both the pullet and laying phase. Each treatment during the adult phase consisted of 9 cages with 9 birds/cage for a total of 36 cages. Automatic infrared cameras were used to monitor behavior of hens in each cage for a 24-h period at 19, 24, 29, 34, 39, 44, 49, 54, 59, 64, and 69 wk of age. Behavior was also recorded twice weekly by an observer in the room where the hens were housed during photophase from 25 to 68 wk of age. Behavioral data were analyzed using ANOVA with repeated measures and the MIXED model procedure. A greater proportion of hens without perches as pullets used the rear perch more during both photophase and scotophase than hens with prior pullet perching experience. Eating and drinking activities of caged adult Leghorns were not impaired by their prior experience to perches as pullets or by the presence of perches in laying cages. It is concluded that providing perches in cages to White Leghorns during pullet rearing did not facilitate use of perches as adults.

  12. Final Report for DUSEL R&D: BetaCage: A Screener of Ultra-Low-Level Radioactive Surface Contamination

    Energy Technology Data Exchange (ETDEWEB)

    Golwala, Sunil R. [California Institute of Technology

    2013-12-20

    The eventual full-size, radiopure BetaCage will be a low-background, atmospheric-pressure neon drift chamber with unprecedented sensitivity to emitters of low-energy electrons and alpha particles. We expect that the prototype BetaCage already developed will be an excellent screener of alpha particles. Both the prototype and final BetaCage will provide new infrastructure for rare-event science.

  13. Effect of multilevel laboratory rat caging system on the well-being of the singly-housed Sprague Dawley rat.

    Science.gov (United States)

    Wheeler, R R; Swan, M P; Hickman, D L

    2015-01-01

    Current regulations emphasize that good husbandry practices allow animals to engage in species appropriate postural adjustments without touching the enclosure walls. This study evaluated the well-being of rats housed in a commercially available multilevel rat caging system, with or without access to the upper level of the caging. The evaluation methodologies included assessment of behavioral observations in the home cage, physiological assessment of metabolism and immune function, and determination of the affective state using a spatial cognitive bias assay. The study determined that rats that were provided access to the full multilevel cage during testing after initial restriction to the lower level of the cage demonstrated behavioral changes consistent with a positive affective state, while those with no changes to their housing situation had no significant differences in their affective states. Rats that were consistently housed with access restricted to the lower level of the cage exhibited a tendency to increased neutrophil:lymphocyte ratios as compared with those provided with access to all levels of the multilevel cage. There were no differences in body weight demonstrated between the experimental groups. Overall use of the cage space, as documented through analysis of behavioral observations in the home cage, demonstrated no significant differences in preferred location in the cage during the light or dark cycles, though rats with access to both levels of the cage were significantly more active during the light cycle. The results of this study suggest that the use of a multilevel caging system may improve the well-being of rats used in research.

  14. Coupling brane fields to bulk supergravity

    Energy Technology Data Exchange (ETDEWEB)

    Parameswaran, Susha L. [Uppsala Univ. (Sweden). Theoretical Physics; Schmidt, Jonas [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2010-12-15

    In this note we present a simple, general prescription for coupling brane localized fields to bulk supergravity. We illustrate the procedure by considering 6D N=2 bulk supergravity on a 2D orbifold, with brane fields localized at the fixed points. The resulting action enjoys the full 6D N=2 symmetries in the bulk, and those of 4D N=1 supergravity at the brane positions. (orig.)

  15. Relative entropy equals bulk relative entropy

    CERN Document Server

    Jafferis, Daniel L; Maldacena, Juan; Suh, S Josephine

    2015-01-01

    We consider the gravity dual of the modular Hamiltonian associated to a general subregion of a boundary theory. We use it to argue that the relative entropy of nearby states is given by the relative entropy in the bulk, to leading order in the bulk gravitational coupling. We also argue that the boundary modular flow is dual to the bulk modular flow in the entanglement wedge, with implications for entanglement wedge reconstruction.

  16. John Cage y su influencia en la obra del video artista Nam June Paik

    Directory of Open Access Journals (Sweden)

    Sarriugarte Gómez, Íñigo

    2009-12-01

    Full Text Available In 1958, the Korean artist Nam June Paik (*1932; †2006 meets in Germany John Cage (*1912; †1992, avant-garde musician, who was deeply interested in the Zen Buddhism. The meeting with Cage was vital, because the North American composer will convince him to orient his career towards the artistic avant-garde, giving up his facet like classic pianist. The philosophy of Cage is refl ected in compositions like “4’ 33’’, from 1952, where the spectator doesn’t listen the sound of the piano, because this isn’t played, but he listens a silence that is interrupted by the environmental sound. There are several versions of this piece, marking the silences by means of processes at random with the “I Ching”. In this sense, the silence used by John Cage is related to the vacuity of the Zen Buddhism. Also, Paik makes use of silence in numerous works, like “1963 TV Clock”, where 24 colour television sets are manipulated, feeling at the same time the silence, interrupted again by the own momentary circumstances of the spectator. This same infl uence of the Zen Buddhism in the music of Cage is observed when argues that the music composed of melodies has the same value than the sound understood by us like noises. This aspect, among others, infl uenced to Paik, whose video images are defi ned like attributes of traditional works that don’t impress to the audience, but they suggest variable conditions. Some of his works related to Cage’s philosophy have been “Hommage à John Cage” from 1959; “Study for pianoforte” from 1960; and “Global Grove” from 1973, where Paik uses as a collage the images of his avant-garde collaborators John Cage, Allen Ginsberg and Merce Cunningham.

    En 1958, el artista coreano Nam June Paik (*1932; †2006 conoce en Alemania a John Cage (*1912; †1992, músico vanguardista, quien estaba profundamente interesado en el budismo zen. Su encuentro con Cage fue vital, ya que el compositor

  17. 33 CFR 127.313 - Bulk storage.

    Science.gov (United States)

    2010-07-01

    ...) WATERFRONT FACILITIES WATERFRONT FACILITIES HANDLING LIQUEFIED NATURAL GAS AND LIQUEFIED HAZARDOUS GAS Waterfront Facilities Handling Liquefied Natural Gas Operations § 127.313 Bulk storage. (a) The...

  18. Applications of bulk high-temperature superconductors

    Science.gov (United States)

    Hull, J. R.

    The development of high-temperature superconductors (HTS's) can be broadly generalized into thin-film electronics, wire applications, and bulk applications. We consider bulk HTS's to include sintered or crystallized forms that do not take the geometry of filaments or tapes, and we discuss major applications for these materials. For the most part applications may be realized with the HTS's cooled to 77 K, and the properties of the bulk HTS's are often already sufficient for commercial use. A non-exhaustive list of applications for bulk HTS's includes trapped field magnets, hysteresis motors, magnetic shielding, current leads, and magnetic bearings. These applications are briefly discussed in this paper.

  19. Biomechanical evaluation of immediate stability with rectangular versus cylindrical interbody cages in stabilization of the lumbar spine

    Directory of Open Access Journals (Sweden)

    Webb John K

    2002-10-01

    Full Text Available Abstract Background Recent cadaver studies show stability against axial rotation with a cylindrical cage is marginally superior to a rectangular cage. The purpose of this biomechanical study in cadaver spine was to evaluate the stability of a new rectangular titanium cage design, which has teeth similar to the threads of cylindrical cages to engage the endplates. Methods Ten motion segments (five L2-3, five L4-5 were tested. From each cadaver spine, one motion segment was fixed with a pair of cylindrical cages (BAK, Sulzer Medica and the other with paired rectangular cages (Rotafix, Corin Spinal. Each specimen was tested in an unconstrained state, after cage introduction and after additional posterior translaminar screw fixation. The range of motion (ROM in flexion-extension, lateral bending, and rotation was tested in a materials testing machine, with +/- 5 Nm cyclical load over 10 sec per cycle; data from the third cycle was captured for analysis. Results ROM in all directions was significantly reduced (p Conclusions There was no significant difference in immediate stability in any direction between the threaded cylindrical cage and the new design of the rectangular cage with endplate teeth.

  20. Small cages with insect couples provide a simple method for a preliminary assessment of mating disruption.

    Science.gov (United States)

    Briand, Françoise; Guerin, Patrick M; Charmillot, Pierre-Joseph; Kehrli, Patrik

    2012-01-01

    Mating disruption by sex pheromones is a sustainable, effective and widely used pest management scheme. A drawback of this technique is its challenging assessment of effectiveness in the field (e.g., spatial scale, pest density). The aim of this work was to facilitate the evaluation of field-deployed pheromone dispensers. We tested the suitability of small insect field cages for a pre-evaluation of the impact of sex pheromones on mating using the grape moths Eupoecilia ambiguella and Lobesia botrana, two major pests in vineyards. Cages consisted of a cubic metal frame of 35 cm sides, which was covered with a mosquito net of 1500 μm mesh size. Cages were installed in the centre of pheromone-treated and untreated vineyards. In several trials, 1 to 20 couples of grape moths per cage were released for one to three nights. The proportion of mated females was between 15 to 70% lower in pheromone-treated compared to untreated vineyards. Overall, the exposure of eight couples for one night was adequate for comparing different control schemes. Small cages may therefore provide a fast and cheap method to compare the effectiveness of pheromone dispensers under standardised semi-field conditions and may help predict the value of setting-up large-scale field trials.

  1. Small Cages with Insect Couples Provide a Simple Method for a Preliminary Assessment of Mating Disruption

    Directory of Open Access Journals (Sweden)

    Françoise Briand

    2012-01-01

    Full Text Available Mating disruption by sex pheromones is a sustainable, effective and widely used pest management scheme. A drawback of this technique is its challenging assessment of effectiveness in the field (e.g., spatial scale, pest density. The aim of this work was to facilitate the evaluation of field-deployed pheromone dispensers. We tested the suitability of small insect field cages for a pre-evaluation of the impact of sex pheromones on mating using the grape moths Eupoecilia ambiguella and Lobesia botrana, two major pests in vineyards. Cages consisted of a cubic metal frame of 35 cm sides, which was covered with a mosquito net of 1500 μm mesh size. Cages were installed in the centre of pheromone-treated and untreated vineyards. In several trials, 1 to 20 couples of grape moths per cage were released for one to three nights. The proportion of mated females was between 15 to 70% lower in pheromone-treated compared to untreated vineyards. Overall, the exposure of eight couples for one night was adequate for comparing different control schemes. Small cages may therefore provide a fast and cheap method to compare the effectiveness of pheromone dispensers under standardised semi-field conditions and may help predict the value of setting-up large-scale field trials.

  2. Effect of housing birds in cages or an aviary system on bone characteristics.

    Science.gov (United States)

    Newman, S; Leeson, S

    1998-10-01

    Sixty-nine-week-old brown egg layers were either maintained in cages or moved to a litter-floored aviary system. After 10 or 20 d, birds were selected at random from within each environment, and their tibiae removed. After drying, bones were measured and then subject to various physical measurements of strength and elasticity. Bone ash and bone calcium content were also measured. Birds maintained in an aviary initially had stronger bones as measured by force (P birds had stronger bones, as assessed by force, than their contemporaries maintained in cages. This same relationship was seen in measures of bone stress (P caged birds had bone ash values that were intermediate between birds held only in cages or the aviary (P > 0.05). Bone calcium content was not influenced by the bird's environment. It appears that the skeleton of caged birds can be affected by providing them with an environment that allows opportunity for increased static and dynamic loading of the bones.

  3. RESULTS OF THE USE OF PEEK CAGES IN THE TREATMENT OF BASILAR INVAGINATION BY GOEL TECHNIQUE

    Directory of Open Access Journals (Sweden)

    Luís Eduardo Carelli Teixeira da Silva

    2016-03-01

    Full Text Available ABSTRACT Objective: Analysis of the use of polyetheretherketone (PEEK cages for atlantoaxial facet realignment and distraction for treatment of basilar invagination by Goel technique. Method: Retrospective descriptive statistical analysis of the neurological status, pain, presence of subsidence and bone fusion with the use of PEEK cages in 8 atlantoaxial joints of 4 patients with basilar invagination. All patients were treated with atlantoaxial facet distraction and realignment and subsequent arthrodesis C1-C2 by the technique of Goel modified by the use of PEEK cage. Results: All patients showed improvement in Nurick neurological assessment scale and Visual Analogue Scale (VAS of pain. There were no cases of subsidence, migration, or damage to the vertebral artery during the insertion of the cage. All joints evolved with bone fusion, assessed by dynamic radiographs, and computed tomography. Two patients developed neuropathic pain in dermatome of C2 and one patient had unilateral vertebral artery injury during C2 instrumentation treated with insertion of pedicle screw to control the bleeding. Conclusion: The results of the treatment of basilar invagination by the Goel technique with the use of PEEK cages shown to be effective and safe although further studies are needed to confirm this use.

  4. Numerical Analysis of Hydrodynamic Behaviors of Two Net Cages with Grid Mooring System Under Wave Action

    Institute of Scientific and Technical Information of China (English)

    CHEN Chang-ping; ZHAO Yun-peng; LI Yu-cheng; DONG Guo-hai; ZHENG Yan-na

    2012-01-01

    Based on rigid kinematics theory and lumped mass method,a mathematical model of the two net cages of grid mooring system under waves is developed.In order to verify the numerical model,a series of physical model tests have been carried out.According to the comparisons between the simulated and the experimental results,it can be found that the simulated and the experimental results agree well in each wave condition.Then,the forces on the mooring lines and the floating collar movement are calculated under different wave conditions.Numerical results show that under the same condition,the forces on the bridle ropes are the largest,followed by forces on the main ropes and the grid ropes.The horizontal and the vertical float collar motion amplitudes increase with the increase of wave height,while the relationship of the horizontal motion amplitude and the wave period is indistinct.The vertical motion amplitude of the two cages is almost the same,while on the respect of horizontal motion amplitude,cage B (behind cage A,as shown in Fig.4) moves much farther than cage A under the same wave condition.The inclination angle of the floating system both in clockwise alongy axis and the counter one enlarges a little with the increase of wave height.

  5. Hydrodynamic coefficients of a simplified floating system of gravity cage in waves

    Institute of Scientific and Technical Information of China (English)

    Chang-wen WU; Fu-kun GUI; Yu-cheng LI; Wei-huan FANG

    2008-01-01

    Numerical simulation and experimental tests were carried out to examine the hydrodynamic behaviors of a double-column floating system of gravity cage under wave conditions. A floating system of gravity cage can be treated as a small-sized floating structure when compared with the wavelengths. The main problem in calculating the wave loads on the small-sized floating structure is to obtain the reasonable force coefficients, which may differ from a submerged structure. In this paper, the floating system of gravity cage is simplified to a 2D problem, where the floating system is set symmetrically under wave conditions. The motion equations were deduced under wave conditions and a specific method was proposed to resolve the problem of wave forces acting on a small-sized floating system of gravity cage at water surface. Results of the numerical method were compared with those from model tests and the hydrodynamic coefficients Cn and C?were studied. It is found that Cn ranges from 0.6 to 1.0 while C?is between 0.4 and 0.6 in this study. The results are useful for research on the hydrodynamic behavior of the deep-water gravity sea cages.

  6. DNA damage in caged Gammarus fossarum amphipods: A tool for freshwater genotoxicity assessment

    Energy Technology Data Exchange (ETDEWEB)

    Lacaze, Emilie [Universite de Lyon, INRA-ENTPE, Laboratoire des Sciences de l' Environnement, rue Maurice Audin, Vaulx en Velin F-69518 (France); Cemagref, Unite de Recherche des Milieux Aquatiques, (UR MALY), 3 bis quai Chauveau, 69336 Lyon, Cedex 9 (France); Devaux, Alain [Universite de Lyon, INRA-ENTPE, Laboratoire des Sciences de l' Environnement, rue Maurice Audin, Vaulx en Velin F-69518 (France); Mons, Raphael [Cemagref, Unite de Recherche des Milieux Aquatiques, (UR MALY), 3 bis quai Chauveau, 69336 Lyon, Cedex 9 (France); Bony, Sylvie [Universite de Lyon, INRA-ENTPE, Laboratoire des Sciences de l' Environnement, rue Maurice Audin, Vaulx en Velin F-69518 (France); Garric, Jeanne [Cemagref, Unite de Recherche des Milieux Aquatiques, (UR MALY), 3 bis quai Chauveau, 69336 Lyon, Cedex 9 (France); Geffard, Alain [EA 2069 URVVC-SE, Laboratoire d' Eco-Toxicologie, UFR Sciences, Moulin de la Housse, BP 1039, 51687 Reims Cedex 2 (France); Geffard, Olivier, E-mail: olivier.geffard@cemagref.fr [Cemagref, Unite de Recherche des Milieux Aquatiques, (UR MALY), 3 bis quai Chauveau, 69336 Lyon, Cedex 9 (France)

    2011-06-15

    The aim of this study was to propose a tool for freshwater environmental genotoxicity assessment using Gammarus fossarum, a high ecologically relevant species. In a first part, gammarids were caged upstream and downstream wastewater treatment plant effluent output. The sensitivity of genotoxic responses of haemocytes, oocytes and spermatozoa was compared using the Comet assay. Spermatozoa appeared to be the most sensitive, suitable and relevant cell type for genotoxicity risk assessment. In a second part, a watershed-scale study was conducted over 2 years to evaluate the applicability of our caging procedure. The genotoxic impact of a contamination was followed, taking into account seasonal variability. DNA damage in spermatozoa exhibited low basal level and low variability in control upstream sites, providing a reliable discrimination of polluted sites. Finally, DNA damage in caged G. fossarum has been proved to be a sensitive and reproducible tool for freshwater genotoxicity assessment. - Highlights: > Two different contamination contexts: WWTP effluents and polymetallic contamination. > DNA damage in caged Gammarus fossarum is a sensitive tool for freshwater quality assessment. > Spermatozoa is the most relevant cell type for biomonitoring freshwater genotoxicity. > Combining biomarker responses with analytical chemistry provides rich ecotoxicological information. - We propose an approach to assess freshwater genotoxicity in the field based on caged Gammarus fossarum (Crustacea, amphipoda).

  7. Spin signatures of photogenerated radical anions in polymer-[70]fullerene bulk-heterojunctions : high-frequency pulsed EPR spectroscopy.

    Energy Technology Data Exchange (ETDEWEB)

    Poluektov, O. G.; Filippone, S.; Martin, N.; Sperlich, A.; Deibel, C.; Dyakonov, V. (Chemical Sciences and Engineering Division); (Univ. Complutense de Madrid); (Univ. of Wurzburg)

    2010-04-14

    Charged polarons in thin films of polymer-fullerene composites are investigated by light-induced electron paramagnetic resonance (EPR) at 9.5 GHz (X-band) and 130 GHz (D-band). The materials studied were poly(3-hexylthiophene) (PHT), [6,6]-phenyl-C61-butyric acid methyl ester (C{sub 60}-PCBM), and two different soluble C{sub 70}-derivates: C{sub 70}-PCBM and diphenylmethano[70]fullerene oligoether (C{sub 70}-DPM-OE). The first experimental identification of the negative polaron localized on the C{sub 70}-cage in polymer-fullerene bulk heterojunctions has been obtained. When recorded at conventional X-band EPR, this signal is overlapping with the signal of the positive polaron, which does not allow for its direct experimental identification. Owing to the superior spectral resolution of the high frequency D-band EPR, we were able to separate light-induced signals from P{sup +} and P{sup -} in PHT-C{sub 70} bulk heterojunctions. Comparing signals from C{sub 70}-derivatives with different side-chains, we have obtained experimental proof that the polaron is localized on the cage of the C{sub 70} molecule.

  8. Spin Signatures of Photogenerated Radical Anions in Polymer-[70]Fullerene Bulk Heterojunctions: High Frequency Pulsed EPR Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Poluektov, Oleg G. [Argonne National Lab. (ANL), Argonne, IL (United States); Filippone, Salvatore [Universidad Complutense de Madrid (Spain); Martin, C. R. [Universidad Complutense de Madrid (Spain); Sperlich, Andreas [Julius-Maximilians Univ. of Wurzburg (Germany); Deibel, Carsten [Julius-Maximilians Univ. of Wurzburg (Germany); Dyakonov, Vladimir [Julius-Maximilians Univ. of Wurzburg (Germany)

    2010-11-18

    Charged polarons in thin films of polymer-fullerene composites are investigated by light-induced electron paramagnetic resonance (EPR) at 9.5 GHz (X-band) and 130 GHz (D-band). The materials studied were poly(3-hexylthiophene) (PHT), [6,6]-phenyl-C61-butyric acid methyl ester (C60-PCBM), and two different soluble C70-derivates: C70-PCBM and diphenylmethano[70]fullerene oligoether (C70-DPM-OE). The first experimental identification of the negative polaron localized on the C70-cage in polymer-fullerene bulk heterojunctions has been obtained. When recorded at conventional X-band EPR, this signal is overlapping with the signal of the positive polaron, which does not allow for its direct experimental identification. Owing to the superior spectral resolution of the high frequency D-band EPR, we were able to separate light-induced signals from P+ and P- in PHT-C70 bulk heterojunctions. Comparing signals from C70-derivatives with different side-chains, we have obtained experimental proof that the polaron is localized on the cage of the C70 molecule.

  9. Spin signatures of photogenerated radical anions in polymer-[70]fullerene bulk heterojunctions: high frequency pulsed EPR spectroscopy.

    Science.gov (United States)

    Poluektov, Oleg G; Filippone, Salvatore; Martín, Nazario; Sperlich, Andreas; Deibel, Carsten; Dyakonov, Vladimir

    2010-11-18

    Charged polarons in thin films of polymer-fullerene composites are investigated by light-induced electron paramagnetic resonance (EPR) at 9.5 GHz (X-band) and 130 GHz (D-band). The materials studied were poly(3-hexylthiophene) (PHT), [6,6]-phenyl-C61-butyric acid methyl ester (C(60)-PCBM), and two different soluble C(70)-derivates: C(70)-PCBM and diphenylmethano[70]fullerene oligoether (C(70)-DPM-OE). The first experimental identification of the negative polaron localized on the C(70)-cage in polymer-fullerene bulk heterojunctions has been obtained. When recorded at conventional X-band EPR, this signal is overlapping with the signal of the positive polaron, which does not allow for its direct experimental identification. Owing to the superior spectral resolution of the high frequency D-band EPR, we were able to separate light-induced signals from P(+) and P(-) in PHT-C(70) bulk heterojunctions. Comparing signals from C(70)-derivatives with different side-chains, we have obtained experimental proof that the polaron is localized on the cage of the C(70) molecule.

  10. Spin signatures of photogenerated radical anions in polymer-[70] fullerene bulk-heterojunctions : high-frequency pulsed EPR spectroscopy.

    Energy Technology Data Exchange (ETDEWEB)

    Poluektov, O. G.; Filippone, S.; Martin, N.; Sperlich, A.; Deibel, C.; Dyakonov, V. (Chemical Sciences and Engineering Division); (Univ. Complutense de Madrid); (Univ. of Wurzburg)

    2010-01-01

    Charged polarons in thin films of polymer-fullerene composites are investigated by light-induced electron paramagnetic resonance (EPR) at 9.5 GHz (X-band) and 130 GHz (D-band). The materials studied were poly(3-hexylthiophene) (PHT), [6,6]-phenyl-C61-butyric acid methyl ester (C{sub 60}-PCBM), and two different soluble C{sub 70}-derivates: C{sub 70}-PCBM and diphenylmethano[70]fullerene oligoether (C{sub 70}-DPM-OE). The first experimental identification of the negative polaron localized on the C{sub 70}-cage in polymer-fullerene bulk heterojunctions has been obtained. When recorded at conventional X-band EPR, this signal is overlapping with the signal of the positive polaron, which does not allow for its direct experimental identification. Owing to the superior spectral resolution of the high frequency D-band EPR, we were able to separate light-induced signals from P{sup +} and P{sup -} in PHT-C{sub 70} bulk heterojunctions. Comparing signals from C{sub 70}-derivatives with different side-chains, we have obtained experimental proof that the polaron is localized on the cage of the C{sub 70} molecule.

  11. Design Concepts of Polycarbonate-Based Intervertebral Lumbar Cages: Finite Element Analysis and Compression Testing

    Directory of Open Access Journals (Sweden)

    J. Obedt Figueroa-Cavazos

    2016-01-01

    Full Text Available This work explores the viability of 3D printed intervertebral lumbar cages based on biocompatible polycarbonate (PC-ISO® material. Several design concepts are proposed for the generation of patient-specific intervertebral lumbar cages. The 3D printed material achieved compressive yield strength of 55 MPa under a specific combination of manufacturing parameters. The literature recommends a reference load of 4,000 N for design of intervertebral lumbar cages. Under compression testing conditions, the proposed design concepts withstand between 7,500 and 10,000 N of load before showing yielding. Although some stress concentration regions were found during analysis, the overall viability of the proposed design concepts was validated.

  12. Tunneling Motion and Antiferroelectric Ordering of Lithium Cations Trapped inside Carbon Cages

    Science.gov (United States)

    Aoyagi, Shinobu; Tokumitu, Akio; Sugimoto, Kunihisa; Okada, Hiroshi; Hoshino, Norihisa; Akutagawa, Tomoyuki

    2016-09-01

    Dielectric and X-ray diffraction measurements of [Li@C60](PF6) single crystals reveal the motion of the Li+ cations inside the C60 cages at low temperature. An increase in the dielectric permittivity below 100 K is consistent with a combined tunneling and hopping motion of the Li+ cation between two positions inside the C60 cage. A phase transition accompanied by a decrease in the dielectric permittivity at TC = 24 K is explained by an antiferroelectric ordering of the Li+ cations. The Li+ ordering is caused by interactions among electric dipole moments formed between the Li+ cations inside and the PF6- anions outside the C60 cages. The electric dipole moments that are switched by the Li+ tunneling and interact with each other are potential qubits in a quantum computer using electric dipole moments.

  13. Tilapia cage culture and the dissolved oxygen trends in Sampaloc Lake, the Philippines.

    Science.gov (United States)

    Santiago, A E; Arcilla, R P

    1993-02-01

    The 28-hectare tilapia cage culture that occupied the 104-hectare Sampaloc Lake, a crater lake, shifted to intensive method in 1986 when tilapia growth slowed done at the beginning of 1982. Thus, commercial feeds became the main source of allochthonous organic matter in the lake. Total feeds given annually for the 28-hectare cage culture at 3 croppings per year amounted to 5250 tons. At feed conversion ratio of 1 : 2 a significant portion of the feeds given ended as organic wastes in the lake. In 1988, tilapia cage operators began experiencing their worst occurrences of fishkill, worth millions of pesos. An assessment of the dissolved oxygen condition of Sampaloc lake in late 1989, 1990 and mid-1991 showed ominous trends which might adversely affect the use of Sampaloc lake for fishery.

  14. Photorelease of GABA with visible light using an inorganic caging group

    Directory of Open Access Journals (Sweden)

    Emiliano Rial Verde

    2008-08-01

    Full Text Available We describe the selective photorelease of γ-amino butyric acid (GABA with a novel caged-GABA compound that uses a ruthenium complex as photosensor. This compound (“RuBi-GABA” can be excited with visible wavelengths, providing greater tissue penetration, less photo-toxicity, and faster photorelease kinetics than currently used UV light-sensitive caged compounds. Using pyramidal neurons from neocortical brain slices, we show that RuBi-GABA uncaging induces GABA-A receptor-mediated responses, has no detectable side effects on endogenous GABAergic and glutamatergic receptors and generates responses with kinetics and spatial resolution comparable to the best caged GABA compounds presently available. Finally, we illustrate two potential applications of RuBi-GABA uncaging: GABA receptor mapping, and optical silencing of neuronal firing.

  15. On the Damper Cage Bar´s Currents Calculation Forsalient Pole Large Synchronous Machina

    Directory of Open Access Journals (Sweden)

    Liliana Vicol

    2008-01-01

    Full Text Available The damper cage bars’ currents occur only when the synchronous machine operates in a dynamic regime and its rotor speed differs from the stator field speed. Basically there are two ways of calculating the damper cage currents, by using the machine equivalent circuit or by employing a 2D or 3D finite element method (FEM analysis. In this paper are discussedtwo methods to calculate the damper cage currents, one based on a coupled field-circuit approach when all the machine dimensions and winding should be known and another based on DC-decay tests conducted with the rotor on d, respectively q axis when all the transient parameters and time constants are obtained. Both methods are quite simple and offer an acceptable accuracy.

  16. Cage rattling does not correlate with the local geometry in molecular liquids

    CERN Document Server

    Bernini, S; Leporini, D

    2016-01-01

    Molecular-dynamics simulations of a liquid of short linear molecules have been performed to investigate the correlation between the particle dynamics in the cage of the neighbors and the local geometry. The latter is characterized in terms of the size and the asphericity of the Voronoi polyhedra. The correlation is found to be poor. In particular, in spite of the different Voronoi volume around the end and the inner monomers of a molecule, all the monomers exhibit coinciding displacement distribution when they are caged (as well as at longer times during the structural relaxation). It is concluded that the fast dynamics during the cage trapping is a non-local collective process involving monomers beyond the nearest neighbours.

  17. Bulk amorphous Mg-based alloys

    DEFF Research Database (Denmark)

    Pryds, Nini

    2004-01-01

    The present paper describes the preparation and properties of bulk amorphous quarternary Mg-based alloys and the influence of additional elements on the ability of the alloy to form bulk amorphous. The main goal is to find a Mg-based alloy system which shows both high strength to weight ratio and...

  18. 27 CFR 20.191 - Bulk articles.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Bulk articles. 20.191... Users of Specially Denatured Spirits Operations by Users § 20.191 Bulk articles. Users who convey articles in containers exceeding one gallon may provide the recipient with a photocopy of subpart G of...

  19. Application of carbon cage (Brantigan) to lumber vertebra diseases. The examination by MRI

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Masato; Nakahara, Shinnosuke; Suenaga, Atsushi; Yamauchi, Taro [Okayama National Hospital (Japan)

    1997-12-01

    Recently several kinds of interlumber spacers have been used for the posterior lumber interbody fusion (PLIF). We have used Brantigan I/F cage (carbon cage) for PLIF. Here we report the results of PLIF and the postoperative MRI. We examined 10 patients (9 men and 10 women) who underwent carbon cage-used PLIF. Patients at surgery were aged from 36 to 77 years (average 61 years). The postoperative observation periods were from 6 months to 17 months (mean 8.2 months). Diseases contained 12 of lumber degenerative sliding disease, 2 of lumber-spine separate disease and 5 of lumber spine stricture complicating the unstable lumber vertebra. We observed synostosis in all cases, and we obtained the improvement rate by JOA score of 71.4%. There was no complications during surgery, except one case of transient neuroparalysis by postoperative hematoma. The carbon cage-used PLIF was effective to minimize sampling of autologous bones and to prevent the crush of bone grafts. MRI was quite effective to evaluate the position of the carbon cage and to judge synostosis. Using MRI we could judge synostosis by the contrast of grafted bones at only 3 months after surgery. The carbon cage transmits X-ray, which makes it easy to judge synostosis. It has the open window to graft autologous bones and the elasticity almost similar to the cortical bone. On the other hand it has some disadvantages; the difficulty to determine the position by the X-ray images, the biological safety, etc. (K.H.)

  20. Specific Internalisation of Gold Nanoparticles into Engineered Porous Protein Cages via Affinity Binding

    Science.gov (United States)

    Peng, Tao; Free, Paul; Fernig, David G.; Lim, Sierin; Tomczak, Nikodem

    2016-01-01

    Porous protein cages are supramolecular protein self-assemblies presenting pores that allow the access of surrounding molecules and ions into their core in order to store and transport them in biological environments. Protein cages’ pores are attractive channels for the internalisation of inorganic nanoparticles and an alternative for the preparation of hybrid bioinspired nanoparticles. However, strategies based on nanoparticle transport through the pores are largely unexplored, due to the difficulty of tailoring nanoparticles that have diameters commensurate with the pores size and simultaneously displaying specific affinity to the cages’ core and low non-specific binding to the cages’ outer surface. We evaluated the specific internalisation of single small gold nanoparticles, 3.9 nm in diameter, into porous protein cages via affinity binding. The E2 protein cage derived from the Geobacillus stearothermophilus presents 12 pores, 6 nm in diameter, and an empty core of 13 nm in diameter. We engineered the E2 protein by site-directed mutagenesis with oligohistidine sequences exposing them into the cage’s core. Dynamic light scattering and electron microscopy analysis show that the structures of E2 protein cages mutated with bis- or penta-histidine sequences are well conserved. The surface of the gold nanoparticles was passivated with a self-assembled monolayer made of a mixture of short peptidols and thiolated alkane ethylene glycol ligands. Such monolayers are found to provide thin coatings preventing non-specific binding to proteins. Further functionalisation of the peptide coated gold nanoparticles with Ni2+ nitrilotriacetic moieties enabled the specific binding to oligohistidine tagged cages. The internalisation via affinity binding was evaluated by electron microscopy analysis. From the various mutations tested, only the penta-histidine mutated E2 protein cage showed repeatable and stable internalisation. The present work overcomes the limitations of

  1. The Design and its Verification of the Double Rotor Double Cage Induction Motor

    Science.gov (United States)

    Sinha, Sumita; Deb, Nirmal K.; Biswas, Sujit K.

    2017-02-01

    The concept of a double rotor motor presented earlier and its equivalent circuit has been developed, showing a non-linear parameter content. The two rotors (which are recommended to be double cage type for development of high starting torque) can run with equal or unequal speed independently, depending on their individual loading. This paper presents the elaborate design procedure, step-by-step, for the double rotor double cage motor and verifies the designed data with that obtained from three separate tests (compared to two for conventional motor) on a prototype, such that optimum performance can be obtained from the motor.

  2. High-pass bird-cage coil for nuclear-magnetic resonance

    Science.gov (United States)

    Watkins, Joel C.; Fukushima, Eiichi

    1988-06-01

    Cylindrical bird-cage coils generate uniform magnetic fields transverse to the cylinder axis for use in the large sample nuclear-magnetic resonance (NMR) experiments. We describe the design and construction of an eight-rung high-pass bird-cage coil to operate at 80 MHz in a cylindrical bore of a superconducting magnet. The coil is 12.7 cm in diameter by 30.5 cm long and has a 7-cm-diam region in the center where the field intensity is within 10% of the average.

  3. Growth and stress of dourado cultivated in cages at different stocking densities

    Directory of Open Access Journals (Sweden)

    Neiva Braun

    2013-08-01

    Full Text Available The objective of this work was to evaluate the growth and the stress levels of juvenile dourado (Salminus brasiliensis cultivated in cages. Fish stocked at densities of 15 (D15 and 30 (D30 fish per square meter were evaluated in a completely randomized design with three replicates. Fish were fed twice a day with extruded ration (42% crude protein. Density influenced only biomass and daily food intake, and glucose and lactate concentrations increased over time. D15 and D30 did not influence the growth of dourado. However, the increase of glucose and lactate levels over time indicates that cultivation in cages is a stressful condition for this species.

  4. Calculation of the environmental capacity of cooling ponds for cage fish farming

    Directory of Open Access Journals (Sweden)

    N. Starco

    2016-12-01

    Full Text Available Purpose. The determination of a maximum annual amount of fish reared in cagesm which does not result in the deterioration of the ecological state of water cooling ponds of the Zmiev Thermal Power Plant and Kursk Nuclear Power Plant series Ι and ΙΙ. Methodology. The specific (per 1 ton of farmed fish nutrient intake necessary for calculations was determined according to the data of own studies. For this purpose, we perfrormed the determination of the input of suspended solids into cooling ponds from cage lines. The calculation of mean fish weight increase during the period of trap exposition bsed on fish farm data allowed calculating the specific input of suspended solids from cages. The effect of artificial feeds and a mixture of feed resideus and fish of fishes collected under cages on water quality were evaluated in the condoitins of laboratory experiments. The effect of fish metabolites on water quality was taken into account according to literature data. Findings. In the specific conditions of the investigated cooling ponds, the environmentally allowable concentrations of biogenic elements are established based on the mineral nitrogen content. With the mean volume of the Zmiev Thermal Power Plant of 40.5 million m3, the total amount of mineral nitrogen, which can be introduced with cage aquaculture residues, is 21.87 tons. When rearing one ton of fish in cages, 91.3 kg of mineral nitrogen get into the cooling pond. Thus, the environmental capacity of the Zmiev Thermal Power Plant cooling pond for cage fish farming is 281.7 tons. Accordingly, the allowable amounts of the production of cage fish farming for the Kursk NPP taking into account N content of 0.406 mgN/dm3 and volume of the cooling pond is 625.5 tons. Originality. For the first time, we calculated the ecological capacity of cooling ponds of the Zmiev TPP and Kursk NPP, series I–II. Practical value. Application of the results presented in the paper will allow creating and

  5. A lightweight field cage for a large TPC prototype for the ILC

    Energy Technology Data Exchange (ETDEWEB)

    Behnke, Ties; Dehmelt, Klaus; Diener, Ralf; Hallermann, Lea; Matsuda, Takeshi; Prahl, Volker; Schade, Peter

    2010-06-15

    We have developed and constructed the field cage of a prototype Time Projection Chamber for research and development studies for a detector at the International Linear Collider. This prototype has an inner diameter of 72 cm and a length of 61 cm. The design of the field cage wall was optimized for a low material budget of 1.21% of a radiation length and a drift field homogeneity of {delta}E/E

  6. Two-component magnetic structure of iron oxide nanoparticles mineralized in Listeria innocua protein cages

    Science.gov (United States)

    Usselman, Robert J.; Klem, Michael T.; Russek, Stephen E.; Young, Mark; Douglas, Trevor; Goldfarb, Ron B.

    2010-06-01

    Magnetometry was used to determine the magnetic properties of maghemite (γ-Fe2O3) nanoparticles formed within Listeria innocua protein cage. The electron magnetic resonance spectrum shows the presence of at least two magnetization components. The magnetization curves are explained by a sum of two Langevin functions in which each filled protein cage contains both a large magnetic iron oxide core plus an amorphous surface consisting of small noncoupled iron oxide spin clusters. This model qualitatively explains the observed decrease in the temperature dependent saturation moment and removes an unrealistic temperature dependent increase in the particle moment often observed in nanoparticle magnetization measurements.

  7. The Design and its Verification of the Double Rotor Double Cage Induction Motor

    Science.gov (United States)

    Sinha, Sumita; Deb, Nirmal K.; Biswas, Sujit K.

    2016-06-01

    The concept of a double rotor motor presented earlier and its equivalent circuit has been developed, showing a non-linear parameter content. The two rotors (which are recommended to be double cage type for development of high starting torque) can run with equal or unequal speed independently, depending on their individual loading. This paper presents the elaborate design procedure, step-by-step, for the double rotor double cage motor and verifies the designed data with that obtained from three separate tests (compared to two for conventional motor) on a prototype, such that optimum performance can be obtained from the motor.

  8. Beak condition and cage density determine abundance and spatial distribution of northern fowl mites, Ornithonyssus sylviarum, and chicken body lice, Menacanthus stramineus, on caged laying hens.

    Science.gov (United States)

    Mullens, B A; Chen, B L; Owen, J P

    2010-12-01

    Adult White Leghorn hens (Hy-Line strain W-36) were inoculated with either northern fowl mites or chicken body lice, and the ectoparasite populations were monitored over periods of 9 to 16 wk. Two beak conditions (beak trimmed or beak intact) and 2 housing densities (1 or 2 hens per 25 × 31 cm suspended wire cage) were tested. Populations of both ectoparasites were at least 10 times lower on beak-intact hens compared with populations on beak-trimmed hens. Cage density did not influence mite numbers, but higher numbers of lice (2 to 3 times) developed on hens held at the higher cage density. Louse distribution on the body and louse population age structure were also influenced by host beak condition. Beak-intact hens had a higher proportion of lice under the wings, whereas beak-trimmed hens had the majority of lice on the lower abdomen. Louse populations on beak-trimmed hens also comprised relatively more immature stages than populations found on beak-intact hens. The effects are likely related to decreased grooming efficiency by beak-trimmed hens and, in the case of lice, the higher host density. The high mite and louse populations on most commercial caged laying hens are probably a direct result of beak trimming. However, selection of more docile breeds that can be held without trimming may allow the hens themselves to reduce ectoparasites below economically damaging levels. This could benefit producers, animal welfare advocates, and human health by reducing 1) costs of beak trimming, 2) pesticide treatment costs (including human and bird chemical exposure concerns), and 3) objections to beak trimming from the animal welfare community.

  9. Biomechanical evaluation of DTRAX® posterior cervical cage stabilization with and without lateral mass fixation

    Directory of Open Access Journals (Sweden)

    Voronov LI

    2016-08-01

    Full Text Available Leonard I Voronov,1,2 Krzysztof B Siemionow,3 Robert M Havey,1,2 Gerard Carandang,2 Avinash G Patwardhan1,2 1Department of Orthopaedic Surgery and Rehabilitation, Loyola University Chicago, Maywood, 2Musculoskeletal Biomechanics Laboratory, Edward Hines Jr. VA Hospital, Hines, 3Department of Orthopaedics, University of Illinois College of Medicine at Chicago, Chicago, IL, USA Introduction: Lateral mass screw (LMS fixation with plates or rods is the current standard procedure for posterior cervical fusion. Recently, implants placed between the facet joints have become available as an alternative to LMS or transfacet screws for patients with cervical spondylotic radiculopathy. The purpose of this study was to evaluate the biomechanical stability of the DTRAX® cervical cage for single- and two-level fusion and compare this to the stability achieved with LMS fixation with rods in a two-level construct.Methods: Seven cadaveric cervical spine (C3–C7 specimens were tested in flexion–extension, lateral bending, and axial rotation to ±1.5 Nm moment without preload (0 N in the following conditions: 1 intact (C3–C7, 2 LMS and rods at C4–C5 and C5–C6, 3 removal of all rods (LMS retained and placement of bilateral posterior cages at C5–C6, 4 bilateral posterior cages at C4–C5 and C5–C6 (without LMS and rods, and 5 C4–C5 and C5–C6 bilateral posterior cages at C4–C5 and C5–C6 with rods reinserted.Results: Bilateral posterior cervical cages significantly reduced range of motion in all tested directions in both single- and multilevel constructs (P<0.05. Similar stability was achieved with bilateral posterior cages and LMS in a two-level construct: 0.6°±0.3° vs 1.2°±0.4° in flexion–­extension (P=0.001, (5.0°±2.6° vs 3.1°±1.3° in lateral bending (P=0.053, (1.3°±1.0° vs 2.2°±0.9° in axial rotation (P=0.091 for posterior cages and LMS, respectively. Posterior cages, when placed as an adjunct to LMS, further reduced

  10. Spray washing, absorbent corn starch powder and dry time to reduce bacterial numbers on soiled boiler transport cage flooring

    Science.gov (United States)

    Most broilers in the U.S. are transported live to slaughter facilities in cages with fiberglass floors. Cages are often used repeatedly without washing and fecal matter deposited on the floor surface can transfer Campylobacter from one flock to another. Drying feces out between uses is an effectiv...

  11. Spray washing, absorbent cornstarch powder, and dry time to reduce bacterial numbers on soiled transport cage flooring

    Science.gov (United States)

    Broiler transport cages are often used repeatedly without washing and fecal matter deposited on the floor surface can transfer Campylobacter from one flock to another. Allowing feces to dry is an effective but slow and logistically impractical means to kill Campylobacter in soiled transport cages. ...

  12. Kinetic stabilization against the oxidation reaction induced by a silaalkane cage in a thiophene-bridged molecular gyroscope.

    Science.gov (United States)

    Setaka, Wataru; Ohmizu, Soichiro; Kira, Mitsuo

    2014-02-01

    Macrocage molecules with a bridged rotor have been synthesized as molecular gyroscopes. The kinetics of the oxidation reaction of the thiophene-bridged molecular gyroscope, whose thiophene ring was bridged inside a silaalkane cage, was investigated. A remarkable kinetic stabilization against the oxidation of the thiophene moiety induced by the molecular cage framework was observed.

  13. Palladium-catalyzed regioselective intramolecular coupling of o-carborane with aromatics via direct cage B-H activation.

    Science.gov (United States)

    Quan, Yangjian; Xie, Zuowei

    2015-03-18

    Palladium-catalyzed intramolecular coupling of o-carborane with aromatics via direct cage B-H bond activation has been achieved, leading to the synthesis of a series of o-carborane-functionalized aromatics in high yields with excellent regioselectivity. In addition, the site selectivity can also be tuned by the substituents on cage carbon atom.

  14. Laying Performance of Wareng Chicken under Free Choice Feeding and Different Cage Density

    Directory of Open Access Journals (Sweden)

    S. Iskandar

    2011-04-01

    Full Text Available The aim of the experiment was to explore the possibility of using free choice feeding technique under different cage density for unselected native chicken. Eighty hens of laying Wareng chicken were divided into two feeding systems. Half of them were fed complete commercial diet of 17% crude protein, with 2800 kcal ME/kg and the other half were subjected to free choice diet. The diets were in mash form and placed in sufficient feed troughs in front of each cage. Each cage was occupied by four or six hens. Free choice feeding hens were served with commercial concentrate (30% crude protein, ground corn and oyster shell, placed separately in feed troughs. Observation was carried out during 24 weeks laying period, starting from 20 to 44 weeks of age. The results showed that egg production (9.35% hen day, and the intake of feed (42.74 g/day, protein (7.01 g/day, energy (116.6 kcal ME/day, calcium (1.99 g/day and phosphorus (0.22 g/day were not affected (P>0.05 by feeding system nor by cage density. The results however indicated that free choice feeding technique provided sufficient nutrients in supporting maximum egg production of unselected native chicken.

  15. Parameters identification of the compound cage rotor induction machine based on linearized Kalman filtering

    Institute of Scientific and Technical Information of China (English)

    王铁成; 李伟力; 孙建伟

    2003-01-01

    A mathematical model has been built up for compound cage rotor induction machine with the rotor re-sistance and leakage inductance in the model identified through Kalman filtering method. Using the identifiedparameters, simulation studies are performed, and simulation results are compared with testing results.

  16. Analysis of Efficiency Characteristics of Squirrel-Cage Induction Motor Loaded With Water System Pump

    Directory of Open Access Journals (Sweden)

    Zbigniew Lukasik

    2007-01-01

    Full Text Available The article presents a method of calculating efficiency of squirrel-cage induction motor. This efficiency depends on frequency of the voltage supplied to the motor and on electrical power. Results of laboratory testing of the motor's efficiency are presented.

  17. Sternum Length and Rib Cage Dimensions Compared with Bodily Proportions in Adults with Cystic Fibrosis

    Directory of Open Access Journals (Sweden)

    Louis-Philippe Laurin

    2012-01-01

    Full Text Available BACKGROUND: A greater structural expansion of the rib cage in females compared with males has been described in cystic fibrosis (CF patients; however, conflicting data exist as to whether an elongation of the bony ribs and sternum contributes to this expansion.

  18. Economic traits and performance of Italian quails reared at different cage stocking densities

    Directory of Open Access Journals (Sweden)

    ABG Faitarone

    2005-03-01

    Full Text Available This study assessed the effect of different cage stocking densities on the performance of Italian quails in the laying period. Two hundred and sixty four quails with 30 weeks of age and 280g mean body weight were used. Birds were randomly assigned to 96 x 33 x 16 cm cages and distributed in a randomized block design with 4 treatments (12, 15, 18 and 21 quails per cage or 264, 211, 176 and 151 cm² per quail, respectively and 4 replicates. Birds were given feed and water ad libitum and submitted to the same experimental conditions. The experimental diet was formulated based on NRC (1994 recommendations. There were no significant differences among treatments for feed conversion per egg mass (kg:kg, percentage of broken eggs and mortality. There was a linear reduction (p<0.05 in egg weight, feed consumption, percentage of production, egg mass and feed conversion per dozen with the increase in stocking density. The gain per house per day was better at the cage density of 151 cm² per bird. However, the density of 211 cm² per bird provided the best gain per bird per day, because this stocking density had better productive indexes when compared with the other treatments.

  19. Novel approach to the behavioural characterization of inbred mice : automated home cage observations

    NARCIS (Netherlands)

    de Visser, L; van den Bos, R; Kuurman, W W; Kas, M J H; Spruijt, B M

    2006-01-01

    Here we present a newly developed tool for continuous recordings and analysis of novelty-induced and baseline behaviour of mice in a home cage-like environment. Aim of this study was to demonstrate the strength of this method by characterizing four inbred strains of mice, C57BL/6, DBA/2, C3H and 129

  20. Control of an Unusual Photo-Claisen Rearrangement in Coumarin Caged Tamoxifen through an Extended Spacer.

    Science.gov (United States)

    Wong, Pamela T; Roberts, Edward W; Tang, Shengzhuang; Mukherjee, Jhindan; Cannon, Jayme; Nip, Alyssa J; Corbin, Kaitlin; Krummel, Matthew F; Choi, Seok Ki

    2017-02-17

    The use of coumarin caged molecules has been well documented in numerous photocaging applications including for the spatiotemporal control of Cre-estrogen receptor (Cre-ERT2) recombinase activity. In this article, we report that 4-hydroxytamoxifen (4OHT) caged with coumarin via a conventional ether linkage led to an unexpected photo-Claisen rearrangement which significantly competed with the release of free 4OHT. The basis for this unwanted reaction appears to be related to the coumarin structure and its radical-based mechanism of uncaging, as it did not occur in ortho-nitrobenzyl (ONB) caged 4OHT that was otherwise linked in the same manner. In an effort to perform design optimization, we introduced a self-immolative linker longer than the ether linkage and identified an optimal linker which allowed rapid 4OHT release by both single-photon and two-photon absorption mechanisms. The ability of this construct to actively control Cre-ERT2 mediated gene modifications was investigated in mouse embryonic fibroblasts (MEFs) in which the expression of a green fluorescent protein (GFP) reporter dependent gene recombination was controlled by 4OHT release and measured by confocal fluorescence microscopy and flow cytometry. In summary, we report the implications of this photo-Claisen rearrangement in coumarin caged compounds and demonstrate a rational linker strategy for addressing this unwanted side reaction.

  1. Coupling of caged molecule dynamics to Johari-Goldstein β-relaxation in metallic glasses

    Science.gov (United States)

    Wang, Z.; Ngai, K. L.; Wang, W. H.; Capaccioli, S.

    2016-01-01

    Three recently published papers have discovered a general property of the fast caged dynamics observed in the glassy states of polyalcohols (S. Capaccioli et al., J. Phys. Chem. B 119, 8800 (2015)), amorphous polymers (K. L. Ngai et al., J. Phys. Chem. B 119, 12502 (2015)), and van der Waals molecular glass-formers (K. L. Ngai et al., J. Phys. Chem. B 119, 12519 (2015)). The fast caged dynamics are manifested as nearly constant loss (NCL) in dielectric and mechanical susceptibility. Shown before in these papers is the intensity of the caged dynamics change temperature dependence at a temperature THF nearly coincident with the secondary glass transition temperature Tgβ, at which the Johari-Goldstein (JG) β-relaxation time τJG reaches ˜103 s. Evidently this finding indicates the coupling of the caged dynamics to the secondary glass transition. The glass-formers considered so far are all soft matters. However, the generality of the phenomenon and its explanation implies that the relation, THF ≈ Tgβ, should be observed in other classes of glass-formers. In this paper, we extend the consideration of the phenomenon and explanation to metallic glasses, which are not soft matter. The experimental data presented show the same phenomenon, supporting its generality and fundamental importance in the physics of glass and glass transition.

  2. Friction moment analysis of space gyroscope bearing with ribbon cage under ultra-low oscillatory motion

    Directory of Open Access Journals (Sweden)

    Jiang Shaona

    2014-10-01

    Full Text Available This paper presents the model of calculating the total friction moment of space gyroscope ball bearings which usually work under ultra-low oscillatory motion and are very sensitive to the friction moment. The aim is to know the proportion of the friction moment caused by each frictional source in the bearing’s total friction moment, which is helpful to optimize the bearing design to deduce the friction moment. In the model, the cage dynamic equations considering six degree-of-freedom and the balls dynamic equations considering two degree-of-freedom were solved. The good trends with different loads between the measured friction moments and computational results prove that the model under constant rate was validated. The computational results show that when the speed was set at 5 r/min, the bearing’s maximum total friction moment when oscillation occurred was obviously larger than that occurred at a constant rate. At the onset of each oscillatory motion, the proportion of the friction moment caused by cage in the bearing’s total friction moment was very high, and it increased with the increasing speed. The analyses of different cage thicknesses and different clearances between cage pocket and ball show that smaller thickness and clearance were preferred.

  3. Energy loss caused by shielding effect of steel cage outside source tube

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The energy loss, produced by shielding effect of steel cage outside the source tube, is quite considerable.With PENELOPE software package, MC results have been obtained based on the simulation of different source conformations. The result illustrates that the naked source tubes can improve the utilization ratio of the cobalt facilities. It demonstrates the applied value of the naked source tube in engineering.

  4. Dynamic Analysis of Hydrodynamic Behavior of A Flatfish Cage System Under Wave Conditions

    Institute of Scientific and Technical Information of China (English)

    崔勇; 关长涛; 万荣; 黄滨; 李娇

    2014-01-01

    This paper presents a simulation model based on the finite element method. The method is used to analyze the motion response and mooring line tension of the flatfish cage system in waves. The cage system consists of top frames, netting, mooring lines, bottom frames, and floats. A series of scaled physical model tests in regular waves are conducted to verify the numerical model. The comparison results show that the simulated and the experimental results agree well under the wave conditions, and the maximum pitch of the bottom frame with two orientations is about 12º. The motion process of the whole cage system in the wave can be described with the computer visualized technology. Then, the mooring line tensions and the motion of the bottom frame with three kinds of weight are calculated under different wave conditions. According to the numerical results, the differences in mooring line tensions of flatfish cages with three weight modes are indistinct. The maximum pitch of the bottom frame decreases with the increase of the bottom weight.

  5. Effect of Elastic Modulus on Biomechanical Properties of Lumbar Interbody Fusion Cage

    Institute of Scientific and Technical Information of China (English)

    Yue Zhu; Fusheng Li; Shujun Li; Yulin Hao; Rui Yang

    2009-01-01

    This work focuses on the influence of elastic modulus on biomechanical properties of lumbar interbody fusion cages by selecting two titanium alloys with different elastic modulus.They were made by a new β type alloy with chemical composition of Ti-24Nb-4Zr-7.6Sn having low Young's modulus ~50 GPa and by a conventional biomedical alloy Ti-6Al-4V having Young's modulus ~110 GPa.The results showed that the designed cages with low modulus (LMC) and high modulus (HMC) can keep identical compression load ~9.8 kN and endure fatigue cycles higher than 5× 106 without functional or mechanical failure under 2.0 kN axial compression.The anti-subsidence ability of both group cages were examined by axial compression of thoracic spine specimens (T9~T10) dissected freshly from the calf with averaged age of 6 months.The results showed that the LMC has better anti-subsidence ability than the HMC (p<0.05).The above results suggest that the cage with low elastic modulus has great potential for clinical applications.

  6. That Entertainment Called a Discussion: The Critical Arts Pedagogy of John Cage

    Science.gov (United States)

    Muller, Otto

    2015-01-01

    Just as John Cage used chance techniques to relinquish control in his practice as a composer, he used pedagogical techniques that facilitated shared learning and experimentation. The tenets of Critical Pedagogy, as laid out by Paulo Freire in "The Pedagogy of the Oppressed," offer insights into the structures and strategies implicit in…

  7. FUZZY LOGIC BASED INTELLIGENT CONTROL OF A VARIABLE SPEED CAGE MACHINE WIND GENERATION SYSTEM

    Science.gov (United States)

    The paper describes a variable-speed wind generation system where fuzzy logic principles are used to optimize efficiency and enhance performance control. A squirrel cage induction generator feeds the power to a double-sided pulse width modulated converter system which either pump...

  8. Romantic Remediation? John Cage and Henry David Thoreau’s Walden State of Mind

    NARCIS (Netherlands)

    Mehring, F.

    2014-01-01

    Rather than identifying Cage as a romantic soul mate of the transcendentalists exhibiting a rebellious attitude against conventions, I will investigate new ways to detect with greater exactness what Sean Wilentz described in the context of David S. Reynolds work on the American Renaissance as “the s

  9. Nicolas Cage otsib kadunud tütart naistesaarelt / Triin Tael

    Index Scriptorium Estoniae

    Tael, Triin

    2006-01-01

    Õudusfilm "Ohvripidu" : režissöör Neil LaBute : peaosas Nicholas Cage : Ameerika Ühendriigid - Saksamaa 2006. Film on uusversioon briti 1973.a. filmist, mille režissöör oli Robin Hardy ja ühes peaosadest Christopher Lee

  10. INTERACTIVE EFFECT OF CAGE DENSITY AND DIETARY BLACK CUMIN LEVEL ON PRODUCTIVE EFFICIENCY IN BROILER CHICKENS

    Directory of Open Access Journals (Sweden)

    L. D. Mahfudz

    2015-09-01

    Full Text Available The present research was aimed to evaluate an interactive effect of cage density and level ofdietary black cumin (BC on productive efficiency of broiler chickens. A total of 270 broiler chickens(initial body weight of 163.12 ± 8.10g were allocated into a completely randomized design with a 3 x 3factorial pattern. The first factor was the cage density (bird/m2 namely, D1 = 8; D2 = 10, and D3 = 12.The second factor was BC level (%, namely, B1 = 1; B2 = 2, and B3 = 3. Feed consumption, bodyweight gain (BWG, feed conversion ratio (FCR, protein digestibility, and income over feed cost(IOFC were the parameters measured. Data were subjected to ANOVA and continued to Duncan test.No interaction between cage density and black cumin on all parameters was observed. Feedconsumption and FCR were increased, but BWG was lowered significantly (P<0.05 due to the cagedensities of 10 and 12 birds/m2 on weeks 2 and 3. Protein digestibility was significantly increased byfeeding 2 and 3% BC. IOFC decreased significantly (P<0.05 when cage densities were 10 and 12birds/m2. In conclusion, the improvement of productive efficiency of broiler chicken reared at the cagedensity of 12 birds /m2 can be sufficiently achieved by feeding 1% black cumin.

  11. Disabling Men: Masculinity and Disability in Al Davison’s Graphic Autobiography, 'The Spiral Cage'

    DEFF Research Database (Denmark)

    McIlvenny, Paul

    2003-01-01

    society . Al Davison was born with severe spina bifida in 1960 in northern England, and his comic book called The Spiral Cage (SC) relates in a rich graphic style the trials and joys of growing up 'disabled' in English society. It was first published in the USA in 1988 by Renegade Press . I will mainly...

  12. Friction moment analysis of space gyroscope bearing with ribbon cage under ultra-low oscillatory motion

    Institute of Scientific and Technical Information of China (English)

    Jiang Shaona; Chen Xiaoyang; Gu Jiaming; Shen Xuejin

    2014-01-01

    This paper presents the model of calculating the total friction moment of space gyro-scope ball bearings which usually work under ultra-low oscillatory motion and are very sensitive to the friction moment. The aim is to know the proportion of the friction moment caused by each frictional source in the bearing’s total friction moment, which is helpful to optimize the bearing design to deduce the friction moment. In the model, the cage dynamic equations considering six degree-of-freedom and the balls dynamic equations considering two degree-of-freedom were solved. The good trends with different loads between the measured friction moments and computational results prove that the model under constant rate was validated. The computational results show that when the speed was set at 5 r/min, the bearing’s maximum total friction moment when oscillation occurred was obviously larger than that occurred at a constant rate. At the onset of each oscillatory motion, the proportion of the friction moment caused by cage in the bearing’s total friction moment was very high, and it increased with the increasing speed. The analyses of different cage thicknesses and different clearances between cage pocket and ball show that smaller thickness and clearance were preferred.

  13. Let the Caged Bird Sing: Using Literature to Teach Developmental Psychology.

    Science.gov (United States)

    Boyatzis, Chris J.

    1992-01-01

    Describes the use of fictional literature in a college-level developmental psychology class. Focuses specifically on Maya Angelou's "I Know Why the Caged Bird Sings" and its relation to several child development topics. Contends that literature should be used more often as part of instruction, especially in the sciences. (CFR)

  14. Superconducting bulk magnets for magnetic levitation systems

    Science.gov (United States)

    Fujimoto, H.; Kamijo, H.

    2000-06-01

    The major applications of high-temperature superconductors have mostly been confined to products in the form of wires and thin films. However, recent developments show that rare-earth REBa 2Cu 3O 7- x and light rare-earth LREBa 2Cu 3O 7- x superconductors prepared by melt processes have a high critical-current density at 77 K and high magnetic fields. These superconductors will promote the application of bulk high-temperature superconductors in high magnetic fields; the superconducting bulk magnet for the Maglev train is one possible application. We investigated the possibility of using bulk magnets in the Maglev system, and examined flux-trapping characteristics of multi-superconducting bulks arranged in array.

  15. Measuring Bulk Flows in Large Scale Surveys

    CERN Document Server

    Feldman, H A; Feldman, Hume A.; Watkins, Richard

    1993-01-01

    We follow a formalism presented by Kaiser to calculate the variance of bulk flows in large scale surveys. We apply the formalism to a mock survey of Abell clusters \\'a la Lauer \\& Postman and find the variance in the expected bulk velocities in a universe with CDM, MDM and IRAS--QDOT power spectra. We calculate the velocity variance as a function of the 1--D velocity dispersion of the clusters and the size of the survey.

  16. Effects of perch access and age on physiological measures of stress in caged White Leghorn pullets.

    Science.gov (United States)

    Yan, F F; Hester, P Y; Enneking, S A; Cheng, H W

    2013-11-01

    The neuroendocrine system controls animals' adaptability to their environments by releasing psychotropic compounds such as catecholamines [epinephrine (EP), norepinephrine (NE), and dopamine (DA)], corticosterone (CORT), and serotonin (5-hydroxytryptamine or 5-HT). Changes of these neuroendocrine compounds have been used as biomarkers of animals' stress responses associated with their well-being. Assuming that pullets, like laying hens, are highly motivated to perch, we hypothesize that pullets with access to perches will experience less stress than pullets that never have access to perches. The objective of this study was to examine the effects of perch access and age on physiological measurements of stress in White Leghorn pullets housed in conventional cages. Hatchlings (n = 1,064) were randomly assigned to 28 cages. Two parallel metal round perches were installed in each of 14 cages assigned the perch treatment, whereas control cages were without perches. Two birds per cage were bled at wk 4, 6, and 12 wk of age. Plasma levels of CORT, DA, EP, and NE, blood concentrations of 5-HT and Trp, and heterophil to lymphocyte ratios were measured. Data were analyzed using a 2-way ANOVA. The perch treatment or its interaction with age did not affect any parameter measured in the study. The increase in the concentrations of circulating EP, NE, 5-HT (numerical increase at 4 wk), and Trp in 4- and 6-wk-old pullets compared with 12-wk-old pullets is unclear, but may have been due to acute handling stress at younger ages. In contrast, concentrations of DA were less at 4 wk compared with levels at 6 and 12 wk of age. Plasma CORT levels and the heterophil to lymphocyte ratio, indicators of long-term stress, were unaffected by age (P = 0.07 and 0.49, respectively). These results indicated that age, but not perch access, affects neuroendocrine homeostasis in White Leghorn pullets. Pullets that were never exposed to perches showed no evidence of eliciting a stress response.

  17. Forms and Balance of Nitrogen and Phosphorus in Cage Culture Waters in Guangdong Province, China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In order to approach the characteristics of nitrogen and phosphorus pollution caused by cage culture and the balance of nitrogen and phosphorus during the process of cage culture, a monitoring was conducted in Daya Bay of Guangdong Province, China from April 2002 to Jane 2003. The results show that the concentrations of total nitrogen (TN) in the waters at the sites with five and ten years of cage culture history are 1.8 and 2.3 times of that at control site respectively. Ammonium (NH3-N) is the main form of nitrogen in spring while nitrate (NO3-) in winter. The concentrations of TN, total dissolved nitrogen (TDN) and dissolved organic nitrogen (DON) are highest in autumn. The concentration of phosphorus increases with the increasing of the culturing time, among which phosphate (PO34-) increases most obviously.The concentrations of total phosphorus (TP) and total dissolved phosphorus (TDP) are highest in autumn. The nitrogen and phosphorus are accumulated significantly in the sediment of cage culture area. The model of N balance in the cage culture area: bait (70.62%) + fry (0.28%) + input by tide (14.8%) + release from sediment (14.3%) = harvest of adult fish (12.07%) + deposition into sediment (28.75%) + output by tide (56.18%) + others (3.00%). The model of P balance: bait (83.11%) + fry (0.17%) + input by tide (12.23%) + release from sediment (4.49%) = harvest of adult fish (8.43%) + deposition into sediment (48.59%) + output by tide (41.94%) + others (1.04%). In one fish growth year, the contents of nitrogen and phosphorus in harvest of adult fish are only 17.0% and 10.1% of the contents of nitrogen and phosphorus in fish bait and fry, wherein 83% of nitrogen and more than 89% of phosphorus in fish bait became marine pollutants.

  18. Prospects for Detecting a Cosmic Bulk Flow

    Science.gov (United States)

    Rose, Benjamin; Garnavich, Peter M.; Mathews, Grant James

    2015-01-01

    The ΛCDM model is based upon a homogeneous, isotropic space-time leading to uniform expansion with random peculiar velocities caused by local gravitation perturbations. The Cosmic Microwave Background (CMB) radiation evidences a significant dipole moment in the frame of the Local Group. This motion is usually explained with the Local Group's motion relative to the background Hubble expansion. An alternative explanation, however, is that the dipole moment is the result of horizon-scale curvature remaining from the birth of space-time, possibly a result of quantum entanglement with another universe. This would appear as a single velocity (a bulk flow) added to all points in space. These two explanations differ observationally on cosmic distance scales (z > 0.1). There have been many differing attempts to detect a bulk flow, many with no detectable bulk flow but some with a bulk flow velocity as large as 1000 km/s. Here we report on a technique based upon minimizing the scatter around the expected cosine distribution of the Hubble redshift residuals with respect to angular distance on the sky. That is, the algorithm searches for a directional dependence of Hubble residuals. We find results consistent with most other bulk flow detections at z Type Ia Supernovae to be ~0.01, whereas the current error (~0.2.) is more than an order of magnitude too large for the detection of bulk flow beyond z~0.05.

  19. A polycaprolactone-tricalcium phosphate composite scaffold as an autograft-free spinal fusion cage in a sheep model.

    Science.gov (United States)

    Li, Yi; Wu, Zhi-gang; Li, Xiao-kang; Guo, Zheng; Wu, Su-hua; Zhang, Yong-quan; Shi, Lei; Teoh, Swee-hin; Liu, Yu-chun; Zhang, Zhi-yong

    2014-07-01

    Titanium (Ti) based spinal fusion cages are frequently used in the clinics for the treatment of spinal degeneration and related diseases, however, their further clinical application is generally harassed by several drawbacks such as stress shielding, non-biodegradability and additional bone grafting procedure. Our earlier work has demonstrated the efficacy of a biodegradable macro-porous polycaprolactone-tricalcium phosphate (PCL-TCP) composite scaffold in promoting bony tissue ingrowth as well as its ability to sustain mechanical loads upon implantation into an orthotopic defect site. In this study, we investigated the use of PCL-TCP scaffold as an autograft-free spinal fusion cage in a preclinical sheep model over 12 months, and compared the fusion efficacy against Ti cages incorporated with autografts. Results showed that despite PCL-TCP scaffold as an autograft-free cage attaining a slower fusion rate at early stage (6 month), it achieved similar degree of spinal fusion efficacy as Ti cages aided with autograft at 12 month post-operation as evidenced by the radiographic and histological evaluation. PCL-TCP cages alone demonstrated better bone ingrowth with 2.6 fold higher bone/interspace ratio (B/I) and more homogeneous bone tissue distribution compared with that of the Ti cages (88.10  ±  3.63% vs. 33.74  ±  2.78%, p CT analysis. Moreover, besides the bone tissue ingrowth, a quantitative approach was illustrated to accurately evaluate the osteointegration of fusion cage with surrounding bone tissue, and showed a 1.36 fold higher degree of osteointegration occurred in PCL-TCP cage group than Ti cage group (CS/PC: 79.31  ±  3.15% vs 58.44  ±  2.43%, p  0.05). The degradation profile of the PCL-TCP cages was noted to increase in tandem with new bone ingrowth into the pores, while maintaining good structural integrity necessary for supporting the spinal interbody segments. Therefore, with the better osteointegration, more bone tissue

  20. Atomically flat Ge buffer layers and alternating shutter growth of CaGe2 for large area germanane

    Science.gov (United States)

    Xu, Jinsong; Katoch, Jyoti; Ahmed, Adam; Pinchuk, Igor; Williams, Robert; McComb, David; Kawakami, Roland

    Germanane (GeH), which is converted from CaGe2 by soaking in HCl acid, has recently attracted interest because of its novel properties, such as large band gap (1.56eV), spin orbit coupling and predictions of high mobility (18000 cm2/Vs). Previously CaGe2 was successfully grown on Ge(111) substrates by molecular beam epitaxy (MBE) growth. But there were cracks between µm-sized islands, which is not desirable for scientific study and application, and limits the material quality. By growing atomically flat Ge buffer layers and using alternating shutter MBE growth, we are able to grow crack-free, large area films of CaGe2 films. Reflection high energy electron diffraction (RHEED) patterns of Ge buffer layer and CaGe2 indicates high quality two dimensional surfaces, which is further confirmed by atomic force microscopy (AFM), showing atomically flat and uniform Ge buffer layer and CaGe2. The appearance of Laue oscillation in X-ray diffraction (XRD) and Kiessig fringes in X-ray reflectivity (XRR) proves the uniformity of CaGe2 film and the smoothness of the interface. The high quality of CaGe2 film makes it promising to explore novel properties of GeH. Funded by NSF MRSEC DMR-1420451.

  1. Photochemical Modulation of Ras-Mediated Signal Transduction using Caged Farnesyltransferase Inhibitors: Activation via One- and Two-Photon Excitation

    Science.gov (United States)

    Abate-Pella, Daniel; Zeliadt, Nicholette A.; Ochocki, Joshua D.; Warmka, Janel K.; Dore, Timothy M.; Blank, David A.; Wattenberg, Elizabeth V.; Distefano, Mark D.

    2012-01-01

    The creation of caged molecules involves the attachment of protecting groups to biologically active compounds such as ligands, substrates, and drugs that can be removed under specific conditions. Photoremovable caging groups are the most common due to their ability to be removed with high spatial and temporal resolution. Here, the synthesis and photochemistry of a caged inhibitor of protein farnesyltransferase, Bhc-FTI, is described. The inhibitor was caged by alkylation of a critical thiol functional group with a Bhc moiety; while Bhc is well established as a protecting group for carboxylates and phosphates, it has not been extensively used to cage sulfhydryls. The resulting caged molecule, Bhc-FTI, can be photolyzed with UV light to release the inhibitor (FTI) that prevents Ras farnesylation, Ras membrane localization and downstream signaling. Finally, it is shown that Bhc-FTI can be uncaged by two-photon excitation to produce FTI at levels sufficient to inhibit Ras localization and alter cell morphology. Given the widespread involvement of Ras proteins in signal transduction pathways, this caged inhibitor should be useful in a plethora of studies. PMID:22492666

  2. Photochemical modulation of Ras-mediated signal transduction using caged farnesyltransferase inhibitors: activation by one- and two-photon excitation.

    Science.gov (United States)

    Abate-Pella, Daniel; Zeliadt, Nicholette A; Ochocki, Joshua D; Warmka, Janel K; Dore, Timothy M; Blank, David A; Wattenberg, Elizabeth V; Distefano, Mark D

    2012-05-07

    The creation of caged molecules involves the attachment of protecting groups to biologically active compounds such as ligands, substrates and drugs that can be removed under specific conditions. Photoremovable caging groups are the most common due to their ability to be removed with high spatial and temporal resolution. Here, the synthesis and photochemistry of a caged inhibitor of protein farnesyltransferase is described. The inhibitor, FTI, was caged by alkylation of a critical thiol group with a bromohydroxycoumarin (Bhc) moiety. While Bhc is well established as a protecting group for carboxylates and phosphates, it has not been extensively used to cage sulfhydryl groups. The resulting caged molecule, Bhc-FTI, can be photolyzed with UV light to release the inhibitor that prevents Ras farnesylation, Ras membrane localization and downstream signaling. Finally, it is shown that Bhc-FTI can be uncaged by two-photon excitation to produce FTI at levels sufficient to inhibit Ras localization and alter cell morphology. Given the widespread involvement of Ras proteins in signal transduction pathways, this caged inhibitor should be useful in a plethora of studies.

  3. Posterior lumbar interbody fusion using one diagonal fusion cage with transpedicular screw/rod fixation.

    Science.gov (United States)

    Zhao, Jie; Hou, Tiesheng; Wang, Xinwei; Ma, Shengzhong

    2003-04-01

    Posterior lumbar interbody fusion (PLIF) using threaded cages has gained wide popularity for lumbosacral spinal disease. Our biomechanical tests showed that PLIF using a single diagonal cage with unilateral facetectomy does add a little to spinal stability and provides equal or even higher postoperative stability than PLIF using two posterior cages with bilateral facetectomy. Studies also demonstrated that cages placed using a posterior approach did not cause the same increase in spinal stiffness seen with pedicle screw instrumentation, and we concluded that cages should not be used posteriorly without other forms of fixation. On the other hand, placement of two cages using a posterior approach does have the disadvantage of risk to the bilateral nerve roots. We therefore performed a prospective study to determine whether PLIF can be accomplished by utilizing a single diagonal fusion cage with the application of supplemental transpedicular screw/rod instrumentation. Twenty-seven patients underwent a PLIF using one single fusion cage (BAK, Sulzer Spine-Tech, Minneapolis, MN, USA) inserted posterolaterally and oriented anteromedially on the symptomatic side with unilateral facetectomy and at the same level supplemental fixation with a transpedicular screw/rod system. The internal fixation systems included 12 SOCON spinal systems (Aesculap AG, Germany) and 15 TSRH spinal systems (Medtronic Sofamor Danek, USA). The inclusion criteria were grade 1 to 2 lumbar isthmic spondylolisthesis, lumbar degenerative spondylolisthesis, and recurrent lumbar disc herniations with instability. Patients had at least 1 year of low back pain and/or unilateral sciatica and a severely restricted functional ability in individuals aged 28-55 years. Patients with more than grade 2 spondylolisthesis or adjacent-level degeneration were excluded from the study. Patients were clinically assessed prior to surgery by an independent assessor; they were then reassessed at 1, 3, 6, 12, 18, and 24

  4. 75 FR 64585 - Bulk Solid Hazardous Materials: Harmonization With the International Maritime Solid Bulk Cargoes...

    Science.gov (United States)

    2010-10-19

    ... nonsubstantive changes, however, to correct grammar, internal paragraph references, and a temperature conversion... means the English version of the ``International Maritime Solid Bulk Cargoes Code'' published by...

  5. Detection of early behavioral markers of Huntington's disease in R6/2 mice employing an automated social home cage

    DEFF Research Database (Denmark)

    Rudenko, Olga; Tkach, Vadim; Berezin, Vladimir;

    2009-01-01

    developed behavior screening system, the IntelliCage, allows automated testing of mouse behavior in the home cage employing individual recognition of animals living in social groups. The present study validates the ability of the IntelliCage system to detect behavioral and cognitive dysfunction in R6/2 mice......Huntington's disease (HD) is an autosomal-dominant neurodegenerative disorder, for which no known cure or effective treatment exists. To facilitate the search for new potential treatments of HD, an automated system for analyzing the behavior of transgenic HD mice is urgently needed. A recently...

  6. Energetics and bonding study of hexamethylenetetramine and fourteen related cage molecules: An ab initio G3(MP2 investigation

    Directory of Open Access Journals (Sweden)

    HO-ON HO

    2005-04-01

    Full Text Available The ab initio G3(MP2method has been applied to hexamethylenetetramine (HMT and fourteen related cage systems. The agreement between the calculated and experimental molecular dimensions, which are available for five of the 15 cage species, ranges from satisfactory to excellent. In addition, the G3(MP2 heat of formation at 298 K for HMT is in excellent accord with experimental results. Hence, the calculated heats of formation for the other 14 cage systems should be reliable estimates.

  7. Biomechanical effects of polyaxial pedicle screw fixation on the lumbosacral segments with an anterior interbody cage support

    Directory of Open Access Journals (Sweden)

    Chen Hsiang-Ho

    2007-03-01

    Full Text Available Abstract Background Lumbosacral fusion is a relatively common procedure that is used in the management of an unstable spine. The anterior interbody cage has been involved to enhance the stability of a pedicle screw construct used at the lumbosacral junction. Biomechanical differences between polyaxial and monoaxial pedicle screws linked with various rod contours were investigated to analyze the respective effects on overall construct stiffness, cage strain, rod strain, and contact ratios at the vertebra-cage junction. Methods A synthetic model composed of two ultrahigh molecular weight polyethylene blocks was used with four titanium pedicle screws (two in each block and two rods fixation to build the spinal construct along with an anterior interbody cage support. For each pair of the construct fixed with polyaxial or monoaxial screws, the linked rods were set at four configurations to simulate 0°, 7°, 14°, and 21° lordosis on the sagittal plane, and a compressive load of 300 N was applied. Strain gauges were attached to the posterior surface of the cage and to the central area of the left connecting rod. Also, the contact area between the block and the cage was measured using prescale Fuji super low pressure film for compression, flexion, lateral bending and torsion tests. Results Our main findings in the experiments with an anterior interbody cage support are as follows: 1 large segmental lordosis can decrease the stiffness of monoaxial pedicle screws constructs; 2 polyaxial screws rather than monoaxial screws combined with the cage fixation provide higher compression and flexion stiffness in 21° segmental lordosis; 3 polyaxial screws enhance the contact surface of the cage in 21° segmental lordosis. Conclusion Polyaxial screws system used in conjunction with anterior cage support yields higher contact ratio, compression and flexion stiffness of spinal constructs than monoaxial screws system does in the same model when the spinal segment

  8. Into the Bulk: A Covariant Approach

    CERN Document Server

    Engelhardt, Netta

    2016-01-01

    I propose a general, covariant way of defining when one region is "deeper in the bulk" than another. This definition is formulated outside of an event horizon (or in the absence thereof) in generic geometries; it may be applied to both points and surfaces, and may be used to compare the depth of bulk points or surfaces relative to a particular boundary subregion or relative to the entire boundary. Using the recently proposed "lightcone cut" formalism, the comparative depth between two bulk points can be determined from the singularity structure of Lorentzian correlators in the dual field theory. I prove that, by this definition, causal wedges of progressively larger regions probe monotonically deeper in the bulk. The definition furthermore matches expectations in pure AdS and in static AdS black holes with isotropic spatial slices, where a well-defined holographic coordinate exists. In terms of holographic RG flow, this new definition of bulk depth makes contact with coarse-graining over both large distances ...

  9. Development of superconductor bulk for superconductor bearing

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chan Joong; Jun, Byung Hyuk; Park, Soon Dong (and others)

    2008-08-15

    Current carrying capacity is one of the most important issues in the consideration of superconductor bulk materials for engineering applications. There are numerous applications of Y-Ba-Cu-O (YBCO) bulk superconductors e.g. magnetic levitation train, flywheel energy storage system, levitation transportation, lunar telescope, centrifugal device, magnetic shielding materials, bulk magnets etc. Accordingly, to obtain YBCO materials in the form of large, single crystals without weak-link problem is necessary. A top seeded melt growth (TSMG) process was used to fabricate single crystal YBCO bulk superconductors. The seeded and infiltration growth (IG) technique was also very promising method for the synthesis of large, single-grain YBCO bulk superconductors with good superconducting properties. 5 wt.% Ag doped Y211 green compacts were sintered at 900 .deg. C {approx} 1200 .deg.C and then a single crystal YBCO was fabricated by an infiltration method. A refinement and uniform distribution of the Y211 particles in the Y123 matrix were achieved by sintering the Ag-doped samples. This enhancement of the critical current density was ascribable to a fine dispersion of the Y211 particles, a low porosity and the presence of Ag particles. In addition, we have designed and manufactured large YBCO single domain with levitation force of 10-13 kg/cm{sup 2} using TSMG processing technique.

  10. Energetics, relative stabilities, and size-dependent properties of nanosized carbon clusters of different families: fullerenes, bucky-diamond, icosahedral, and bulk-truncated structures.

    Science.gov (United States)

    Yu, M; Chaudhuri, I; Leahy, C; Wu, S Y; Jayanthi, C S

    2009-05-14

    Structures and relative stabilities of carbon clusters belonging to different families have been investigated for diameters d simulation. Carbon clusters studied include fullerenes and fullerene-derived structures (e.g., cages and onions), icosahedral structures, bucky-diamond structures, and clusters cut from the bulk diamond with spherical and facetted truncations. The reason for using a semiempirical MD is partly due to the large number of different cases (or carbon allotropes) investigated and partly due to the size of the clusters investigated in this work. The particular flavor of the semiempirical MD scheme is based on a self-consistent and environment-dependent Hamiltonian developed in the framework of linear combination of atomic orbitals. We find that (i) among the families of carbon clusters investigated, fullerene structures have the lowest energy with the relative energy ordering being E(fullerene) structures is likely at d approximately 8 nm, (iii) the highest occupied molecular orbital-lowest unoccupied molecular orbital gap as a function of the diameter for the case of fullerenes shows an oscillatory behavior with the gap ranging from 2 eV to 6 meV, and the gap approaching that of gapless graphite for d > 3.5 nm, and (iv) there can be three types of phase transformations depending on the manner of heating and cooling in our simulated annealing studies: (a) a bucky-diamond structure --> an onionlike structure, (b) an onionlike --> a cage structure, and (c) a bucky-diamond --> a cage structure.

  11. Bulk fields from the boundary OPE

    CERN Document Server

    Guica, Monica

    2016-01-01

    Previous work has established an equality between the geodesic integral of a free bulk field in AdS and the contribution of the conformal descendants of its dual CFT primary operator to the OPE of two other operators inserted at the endpoints of the geodesic. Working in the context of AdS$_3$/CFT$_2$, we extend this relation to include all $1/N$ corrections to the bulk field obtained by dressing it with i) a $U(1)$ current and ii) the CFT stress tensor, and argue it equals the contribution of the Ka\\v{c}-Moody/the Virasoro block to the respective boundary OPE. This equality holds for a particular framing of the bulk field to the boundary that involves a split Wilson line.

  12. A Diphoton Resonance from Bulk RS

    CERN Document Server

    Csaki, Csaba

    2016-01-01

    Recent LHC data hints at a 750 GeV mass resonance that decays into two photons. A significant feature of this resonance is that its decays to Higges and to any other Standard Model particles are so far too low to be detected. Such a state has a compelling explanation in terms of a scalar or a pseudoscalar that is strongly coupled to vector states charged under the Standard Model gauge groups. We argue that if the state is a scalar, some form of sequestering is likely to be necessary to naturally explain the suppressed scalar-Higgs interactions. Such a scenario is readily accommodated in bulk RS with a scalar localized in the bulk away from the Higgs. Turning this around, we argue that a good way to find the elusive bulk RS model might be the search for a resonance with prominent couplings to gauge bosons.

  13. Bulk Comptonization by Turbulence in Accretion Disks

    CERN Document Server

    Kaufman, J

    2016-01-01

    Radiation pressure dominated accretion discs around compact objects may have turbulent velocities that greatly exceed the electron thermal velocities within the disc. Bulk Comptonization by the turbulence may therefore dominate over thermal Comptonization in determining the emergent spectrum. Bulk Comptonization by divergenceless turbulence is due to radiation viscous dissipation only. It can be treated as thermal Comptonization by solving the Kompaneets equation with an equivalent "wave" temperature, which is a weighted sum over the power present at each scale in the turbulent cascade. Bulk Comptonization by turbulence with non-zero divergence is due to both pressure work and radiation viscous dissipation. Pressure work has negligible effect on photon spectra in the limit of optically thin turbulence, and in this limit radiation viscous dissipation alone can be treated as thermal Comptonization with a temperature equivalent to the full turbulent power. In the limit of extremely optically thick turbulence, ra...

  14. A diphoton resonance from bulk RS

    Science.gov (United States)

    Csáki, Csaba; Randall, Lisa

    2016-07-01

    Recent LHC data hinted at a 750 GeV mass resonance that decays into two photons. A significant feature of this resonance is that its decays to any other Standard Model particles would be too low to be detected so far. Such a state has a compelling explanation in terms of a scalar or a pseudoscalar that is strongly coupled to vector states charged under the Standard Model gauge groups. Such a scenario is readily accommodated in bulk RS with a scalar localized in the bulk away from but close to the Higgs. Turning this around, we argue that a good way to find the elusive bulk RS model might be the search for a resonance with prominent couplings to gauge bosons.

  15. Orchestrating Bulk Data Movement in Grid Environments

    Energy Technology Data Exchange (ETDEWEB)

    Vazhkudai, SS

    2005-01-25

    Data Grids provide a convenient environment for researchers to manage and access massively distributed bulk data by addressing several system and transfer challenges inherent to these environments. This work addresses issues involved in the efficient selection and access of replicated data in Grid environments in the context of the Globus Toolkit{trademark}, building middleware that (1) selects datasets in highly replicated environments, enabling efficient scheduling of data transfer requests; (2) predicts transfer times of bulk wide-area data transfers using extensive statistical analysis; and (3) co-allocates bulk data transfer requests, enabling parallel downloads from mirrored sites. These efforts have demonstrated a decentralized data scheduling architecture, a set of forecasting tools that predict bandwidth availability within 15% error and co-allocation architecture, and heuristics that expedites data downloads by up to 2 times.

  16. Multiphase composites with extremal bulk modulus

    DEFF Research Database (Denmark)

    Gibiansky, L. V.; Sigmund, Ole

    2000-01-01

    This paper is devoted to the analytical and numerical study of isotropic elastic composites made of three or more isotropic phases. The ranges of their effective bulk and shear moduli are restricted by the Hashin-Shtrikman-Walpole (HSW) bounds. For two-phase composites, these bounds are attainable......, that is, there exist composites with extreme bulk and shear moduli. For multiphase composites, they may or may not be attainable depending on phase moduli and volume fractions. Sufficient conditions of attainability of the bounds and various previously known and new types of optimal composites...... are described. Most of our new results are related to the two-dimensional problem. A numerical topology optimization procedure that solves the inverse homogenization problem is adopted and used to look for two-dimensional three-phase composites with a maximal effective bulk modulus. For the combination...

  17. A stereoscopic look into the bulk

    Science.gov (United States)

    Czech, Bartlomiej; Lamprou, Lampros; McCandlish, Samuel; Mosk, Benjamin; Sully, James

    2016-07-01

    We present the foundation for a holographic dictionary with depth perception. The dictionary consists of natural CFT operators whose duals are simple, diffeomorphisminvariant bulk operators. The CFT operators of interest are the "OPE blocks," contributions to the OPE from a single conformal family. In holographic theories, we show that the OPE blocks are dual at leading order in 1 /N to integrals of effective bulk fields along geodesics or homogeneous minimal surfaces in anti-de Sitter space. One widely studied example of an OPE block is the modular Hamiltonian, which is dual to the fluctuation in the area of a minimal surface. Thus, our operators pave the way for generalizing the Ryu-Takayanagi relation to other bulk fields.

  18. Spherically symmetric brane spacetime with bulk gravity

    Science.gov (United States)

    Chakraborty, Sumanta; SenGupta, Soumitra

    2015-01-01

    Introducing term in the five-dimensional bulk action we derive effective Einstein's equation on the brane using Gauss-Codazzi equation. This effective equation is then solved for different conditions on dark radiation and dark pressure to obtain various spherically symmetric solutions. Some of these static spherically symmetric solutions correspond to black hole solutions, with parameters induced from the bulk. Specially, the dark pressure and dark radiation terms (electric part of Weyl curvature) affect the brane spherically symmetric solutions significantly. We have solved for one parameter group of conformal motions where the dark radiation and dark pressure terms are exactly obtained exploiting the corresponding Lie symmetry. Various thermodynamic features of these spherically symmetric space-times are studied, showing existence of second order phase transition. This phenomenon has its origin in the higher curvature term with gravity in the bulk.

  19. Making bulk-conductive glass microchannel plates

    Science.gov (United States)

    Yi, Jay J. L.; Niu, Lihong

    2008-02-01

    The fabrication of microchannel plate (MCP) with bulk-conductive characteristics has been studied. Semiconducting clad glass and leachable core glass were used for drawing fibers and making MCP. Co-axial single fiber was drawn from a platinum double-crucible in an automatic fiberizing system, and the fibers were stacked and redrawn into multifiber by a special gripping mechanism. The multifibers were stacked again and the boule was made and sliced into discs. New MCPs were made after chemically leaching process without the traditional hydrogen firing. It was shown that bulk-conductive glass MCP can operate at higher voltage with lower noise.

  20. Synthesis of Bulk Superconducting Magnesium Diboride

    Directory of Open Access Journals (Sweden)

    Margie Olbinado

    2002-06-01

    Full Text Available Bulk polycrystalline superconducting magnesium diboride, MgB2, samples were successfully prepared via a one-step sintering program at 750°C, in pre Argon with a pressure of 1atm. Both electrical resistivity and magnetic susceptibility measurements confirmed the superconductivity of the material at 39K, with a transition width of 5K. The polycrystalline nature, granular morphology, and composition of the sintered bulk material were confirmed using X-ray diffractometry (XRD, scanning electron microscopy (SEM, and energy dispersive X-ray analysis (EDX.

  1. Towards a Reconstruction of General Bulk Metrics

    CERN Document Server

    Engelhardt, Netta

    2016-01-01

    We prove that the metric of a general holographic spacetime can be reconstructed (up to an overall conformal factor) from distinguished spatial slices - "light-cone cuts" - of the conformal boundary. Our prescription is covariant and applies to bulk points in causal contact with the boundary. Furthermore, we describe a procedure for determining the light-cone cuts corresponding to bulk points in the causal wedge of the boundary in terms of the divergences of correlators in the dual field theory. Possible extensions for determining the conformal factor and including the cuts of points outside of the causal wedge are discussed. We also comment on implications for subregion/subregion duality.

  2. STUDIES ON THE SYNTHESES AND PROPERTIES OF SNAKE—CAGE TYPE CHELATE RESINS

    Institute of Scientific and Technical Information of China (English)

    QURongjun; WANGShen; 等

    1999-01-01

    Using carboxymethyl chitosan(CM-CTS) as snake resin,B-62 resin crosslinked by triethylentetraamine(TETA)as cage resin,a series of novel snake-cage type resin were synthesized.Such factors as the best synthetic conditions,the swelling and regeneration properties.and the sorption capactities of the above mentioned resins for metal ions were investigated.The experimental results show these resins have good swelling properties and mechanical stability,and do not run off in organic and inorganic solvents.The sorption capactities of them for Cu2+,Ni2+,Zn2+,and Pb2+ were 0.89,0.54,0.32,and 0.22mmol/g,rspectively.

  3. Nuclear spin conversion of water inside fullerene cages detected by low-temperature nuclear magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Mamone, Salvatore, E-mail: s.mamone@soton.ac.uk; Concistrè, Maria; Carignani, Elisa; Meier, Benno; Krachmalnicoff, Andrea; Johannessen, Ole G.; Denning, Mark; Carravetta, Marina; Whitby, Richard J.; Levitt, Malcolm H., E-mail: mhl@soton.ac.uk [School of Chemistry, University of Southampton, Southampton SO17 1BJ (United Kingdom); Lei, Xuegong; Li, Yongjun [Department of Chemistry, Columbia University, New York, New York 10027 (United States); Goh, Kelvin; Horsewill, Anthony J. [School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD (United Kingdom)

    2014-05-21

    The water-endofullerene H{sub 2}O@C{sub 60} provides a unique chemical system in which freely rotating water molecules are confined inside homogeneous and symmetrical carbon cages. The spin conversion between the ortho and para species of the endohedral H{sub 2}O was studied in the solid phase by low-temperature nuclear magnetic resonance. The experimental data are consistent with a second-order kinetics, indicating a bimolecular spin conversion process. Numerical simulations suggest the simultaneous presence of a spin diffusion process allowing neighbouring ortho and para molecules to exchange their angular momenta. Cross-polarization experiments found no evidence that the spin conversion of the endohedral H{sub 2}O molecules is catalysed by {sup 13}C nuclei present in the cages.

  4. Numerical Simulation of Dynamic Response of A Net Cage for Flatfish in Waves

    Institute of Scientific and Technical Information of China (English)

    桂福坤; 赵云鹏; 许条建; 关长涛

    2014-01-01

    A numerical model of flatfish cage is built based on the lumped mass method and the principle of rigid body kinematics. To validate the numerical model, a series of physical model tests are conducted in the wave flume. The numerical results correspond well with the data sets from physical model test. The effect of weight of bottom frame, height of fish net and net shape on motion responses of fish cage and tension force on mooring lines is then analyzed. The results indicate that the vertical displacements of float collar and bottom frame decrease with the increase in the weight of bottom frame; the maximum tension force on mooring lines increases with the increasing weight of bottom frame. The inclination angles of float collar and bottom frame decrease with the increasing net height; the maximum tension force increases obviously with the increase of net height.

  5. Simulation of alternative genetic control systems for Aedes aegypti in outdoor cages and with a computer

    Energy Technology Data Exchange (ETDEWEB)

    Curtis, C.F.; Lorimer, N.; Rai, K.S.; Suguna, S.G.; Uppal, D.K.; Kazmi, S.J.; Hallinan, E.; Dietz, K.

    1976-06-01

    Cycling populations of A. aegypti of wild origin were established in outdoor cages. Releases were then made for 32 to 43 days of either males carrying chromosome translocations cr males of the sex ratio distorter type. The translocation caused a maximum of 50% sterility, but this declined rapidly after termination of releases. The distorter males depressed the proportion of females among the pupae produced in the cage to a minimum of 35% and the distortion of sex ratio persisted for 13 weeks following termination of releases. It was possible to simulate the effects of the releases with a computer. Simulations were aslo made of standard release schedules of three types of genetic material. A strain carrying both sex ratio distortion and a translocation gave the most effective population suppression.

  6. Cyclic Water Clusters in Tape-Like and Cage-Like Structures

    Directory of Open Access Journals (Sweden)

    Fuhou Lei

    2011-04-01

    Full Text Available Controlling the ratio of 2,2′-bpy to benzene-1,3,5-tricarboxylic acid produces two interesting complexes, namely [Co(2,2′-bpy3] (SO4 8.5H2O (1 and [Cu2(BTCA (2,2′-bpy4] (OH (2,2′-bpy0.5·14H2O (2 (H3BTCA = benzene-1,3,5-tricarboxylic acid, 2,2′-bpy = 2,2′-bipyridine. We report the structural evidence in the solid state of discrete lamellar water cluster conformations. These units are found to act as supramolecular glue in the aggregation of cobalt (II or copper (II complexes to give three dimensional cage-like networks through hydrogen-bonding. It is interesting that the structure of complex 1 contains a 3D negatively charged cage.

  7. Isolation of avian serotype 3 paramyxoviruses from imported caged birds in Israel.

    Science.gov (United States)

    Shihmanter, E; Weisman, Y; Lublin, A; Mahani, S; Panshin, A; Lipkind, M

    1998-01-01

    Ten avian serotype 3 paramyxoviruses were isolated for the first time in Israel from passerine and psittacine imported caged birds. The birds were submitted for investigation of an illness characterized by nonspecific signs of weakness, anorexia, vomiting, and sneezing. In addition, only the parakeets developed specific neurologic signs. In bacteriologic and pathologic investigation, cachexia and diarrhea were observed in both groups of birds. In psittacines, considerable alterations were observed in lungs, liver, and spleen. Some nonviral pathogens were occasionally isolated. The isolates appeared to belong to serotype 3b avian paramyxovirus (APMV), the prototype strain of which is APMV-3b/parakeet/Netherlands/449/75. The isolation of APMV-3 viruses from imported caged birds may represent a way of introduction of these viruses into the country.

  8. Observation of gold sub-nanocluster nucleation within a crystalline protein cage

    Science.gov (United States)

    Maity, Basudev; Abe, Satoshi; Ueno, Takafumi

    2017-01-01

    Protein scaffolds provide unique metal coordination environments that promote biomineralization processes. It is expected that protein scaffolds can be developed to prepare inorganic nanomaterials with important biomedical and material applications. Despite many promising applications, it remains challenging to elucidate the detailed mechanisms of formation of metal nanoparticles in protein environments. In the present work, we describe a crystalline protein cage constructed by crosslinking treatment of a single crystal of apo-ferritin for structural characterization of the formation of sub-nanocluster with reduction reaction. The crystal structure analysis shows the gradual movement of the Au ions towards the centre of the three-fold symmetric channels of the protein cage to form a sub-nanocluster with accompanying significant conformational changes of the amino-acid residues bound to Au ions during the process. These results contribute to our understanding of metal core formation as well as interactions of the metal core with the protein environment. PMID:28300064

  9. Exogenous control over intracellular acidification: Enhancement via proton caged compounds coupled to gold nanoparticles.

    Science.gov (United States)

    Carbone, Marilena; Sabbatella, Gianfranco; Antonaroli, Simonetta; Remita, Hynd; Orlando, Viviana; Biagioni, Stefano; Nucara, Alessandro

    2015-11-01

    The pH regulation has a fundamental role in several intracellular processes and its variation via exogenous compounds is a potential tool for intervening in the intracellular processes. Proton caged compounds (PPCs) release protons upon UV irradiation and may efficiently provoke intracellular on-command acidification. Here, we explore the intracellular pH variation, when purposely synthesized PCCs are coupled to gold nanoparticles (AuNPs) and dosed to HEK-293 cells. We detected the acidification process caused by the UV irradiation by monitoring the intensity of the asymmetric stretching mode of the CO(2) molecule at 2343 cm(-1). The comparison between free and AuNPs functionalized proton caged compound demonstrates a highly enhanced CO(2) yield, hence pH variation, in the latter case. Finally, PCC functionalized AuNPs were marked with a purposely synthesized fluorescent marker and dosed to HEK-293 cells. The corresponding fluorescence optical images show green grains throughout the whole cytoplasm.

  10. Spatial cognition in a virtual reality home-cage extension for freely moving rodents.

    Science.gov (United States)

    Kaupert, Ursula; Thurley, Kay; Frei, Katja; Bagorda, Francesco; Schatz, Alexej; Tocker, Gilad; Rapoport, Sophia; Derdikman, Dori; Winter, York

    2017-01-11

    Virtual reality environments are part of a powerful tool set to investigate brain mechanisms of behavior in animals. For this, animals are mostly head-fixed or in a harness, and training for cognitively more complex VR paradigms is time consuming. A virtual reality apparatus allowing free animal movement and 24/7 operator-independent training of tasks would enable many new applications. Key prospective usages include brain imaging in behaving animals carrying a miniaturized mobile device such as a fluorescence microscope, or an optetrode. Here we introduce the servoball, a spherical virtual reality treadmill that is connected to the home cage from where single individuals can voluntarily enter through an RFID automated access control. We automatically trained rats that demonstrated use of visual or acoustic cues to solve spatial cognitive tasks, and recorded spatially modulated entorhinal cells. This integrated home cage with VR-arena experimental system permits highly efficient experimentation for complex cognitive experiments.

  11. Utilisation of dried caged-hen manure and cassava peels for intensive sheep production.

    Science.gov (United States)

    Okeudo, N J; Adegbola, A A

    1993-11-01

    Twenty grower ewes with an average weight of 14.3 +/- 3.7 kg were allotted to 5 dietary treatments. The diets contained 0, 13, 25, 35 and 45% dried caged-hen manure which replaced 0, 25, 50, 75 and 100%, respectively of the conventional protein supplements. The animals were fed 55.0 g/w0.75 kg/day of the concentrate food during a 104 days growth study. Air dried cassava peels and water were also provided ad libitum. The differences in average total dry matter intake were not statistically significant. The higher the manure content in the diets, the lower the energy content and the higher the cassava peels intake. No statistical differences were found in growth rates. The efficiency of food conversion decreased progressively though insignificantly. It was concluded that sheep can be fed caged-hen manure as the sole protein supplement in cassava peel based diets.

  12. Validation of an automated mite counter for Dermanyssus gallinae in experimental laying hen cages.

    Science.gov (United States)

    Mul, Monique F; van Riel, Johan W; Meerburg, Bastiaan G; Dicke, Marcel; George, David R; Groot Koerkamp, Peter W G

    2015-08-01

    For integrated pest management (IPM) programs to be maximally effective, monitoring of the growth and decline of the pest populations is essential. Here, we present the validation results of a new automated monitoring device for the poultry red mite (Dermanyssus gallinae), a serious pest in laying hen facilities world-wide. This monitoring device (called an "automated mite counter") was validated in experimental laying hen cages with live birds and a growing population of D. gallinae. This validation study resulted in 17 data points of 'number of mites counted' by the automated mite counter and the 'number of mites present' in the experimental laying hen cages. The study demonstrated that the automated mite counter was able to track the D. gallinae population effectively. A wider evaluation showed that this automated mite counter can become a useful tool in IPM of D. gallinae in laying hen facilities.

  13. Stability of gold cages (Au16 and Au17) at finite temperature

    Indian Academy of Sciences (India)

    Prachi Chandrachud; Kavita Joshi; Sailaja Krishnamurty; D G Kanhere

    2009-05-01

    We have employed ab initio molecular dynamics to investigate the stability of the smallest gold cages, namely Au16 and Au17, at finite temperatures. First, we obtain the ground state structure along with at least 50 distinct isomers for both the clusters. This is followed by the finite temperature simulations of these clusters. Each cluster is maintained at 12 different temperatures for a time period of at least 150 ps. Thus, the total simulation time is of the order of 2.4 ns for each cluster. We observe that the cages are stable at least up to 850 K. Although both clusters melt around the same temperature, i.e. around 900 K, Au17 shows a peak in the heat capacity curve in contrast to the broad peak seen for Au16.

  14. Numerical simulation of dynamic response of a net cage for flatfish in waves

    Science.gov (United States)

    Gui, Fu-kun; Zhao, Yun-peng; Xu, Tiao-jian; Guan, Chang-tao

    2014-03-01

    A numerical model of flatfish cage is built based on the lumped mass method and the principle of rigid body kinematics. To validate the numerical model, a series of physical model tests are conducted in the wave flume. The numerical results correspond well with the data sets from physical model test. The effect of weight of bottom frame, height of fish net and net shape on motion responses of fish cage and tension force on mooring lines is then analyzed. The results indicate that the vertical displacements of float collar and bottom frame decrease with the increase in the weight of bottom frame; the maximum tension force on mooring lines increases with the increasing weight of bottom frame. The inclination angles of float collar and bottom frame decrease with the increasing net height; the maximum tension force increases obviously with the increase of net height.

  15. Observation of gold sub-nanocluster nucleation within a crystalline protein cage

    Science.gov (United States)

    Maity, Basudev; Abe, Satoshi; Ueno, Takafumi

    2017-03-01

    Protein scaffolds provide unique metal coordination environments that promote biomineralization processes. It is expected that protein scaffolds can be developed to prepare inorganic nanomaterials with important biomedical and material applications. Despite many promising applications, it remains challenging to elucidate the detailed mechanisms of formation of metal nanoparticles in protein environments. In the present work, we describe a crystalline protein cage constructed by crosslinking treatment of a single crystal of apo-ferritin for structural characterization of the formation of sub-nanocluster with reduction reaction. The crystal structure analysis shows the gradual movement of the Au ions towards the centre of the three-fold symmetric channels of the protein cage to form a sub-nanocluster with accompanying significant conformational changes of the amino-acid residues bound to Au ions during the process. These results contribute to our understanding of metal core formation as well as interactions of the metal core with the protein environment.

  16. Cup-cage construct for acute fractures of the acetabulum, re-defining indications.

    Science.gov (United States)

    Chana-Rodríguez, Francisco; Villanueva-Martínez, Manuel; Rojo-Manaute, Jose; Sanz-Ruíz, Pablo; Vaquero-Martín, Javier

    2012-12-01

    Acetabular fractures in the elderly are challenging injuries. The use of a trabecular metal acetabular cage was investigated as the treatment option in a series of elderly patients with acetabular fractures. At a 2-year follow up, 6 elderly patients were found to have mimimum pain, increased function, and increased scores using the Merle d'Aubigné and Postel system modified by Charnley. Radiographically, the areas of morsellised autograft that surrounded the cups were seen to have incorporated uniformly well, and the acetabular fractures were healed within six months after surgery. No mechanical failure, screw breakage, loosening, or migration was noticed. This novel indication of the cup-cage construction that uses revision techniques, for selected patients and fractures, to achieve an acute stable reconstruction, should be considered as an alternative reconstruction option in elderly patients presenting with acetabular fractures.

  17. Pentagonal dodecahedron methane hydrate cage and methanol system—An ab initio study

    Indian Academy of Sciences (India)

    Snehanshu Pal; T K Kundu

    2013-03-01

    Density functional theory based studies have been performed to elucidate the role of methanol as an methane hydrate inhibitor. A methane hydrate pentagonal dodecahedron cage’s geometry optimization, natural bond orbital (NBO) analysis, Mullikan charge determination, electrostatic potential evaluation and vibrational frequency calculation with and without the presence of methanol using WB97XD/6-31++G(d,p) have been carried out. Calculated geometrical parameters and interaction energies indicate that methanol destabilizes pentagonal dodecahedron methane hydrate cage (1CH4@512) with and without the presence of sodium ion. NBO analysis and red shift of vibrational frequency reveal that hydrogen bond formation between methanol and water molecules of 1CH4@512 cage is favourable subsequently after breaking its original hydrogen bonded network.

  18. Calibration of excitation function measurement based on corona cage test results.

    Science.gov (United States)

    Lan, Lei; Chen, Xiaoyue; Wen, Xishan; Li, Wei; Xiao, Guozhou

    2016-11-01

    Corona cage approaches are crucial for research on the corona characteristics of conductors. Calibration is an indispensable task for determining excitation functions, which are used to predict corona performance of long transmission lines through extrapolation from measurements of short lines in corona cages. In this paper, the amplification factor G is calculated through a frequently adopted method, propagation analysis of high-frequency corona current along a short line. Another convenient calibration method, based on distributed parameter equivalent circuits, is established. The results for G obtained through propagation analysis and equivalent circuits are compared. To verify the rationality of calculation parameters in propagation analysis and equivalent circuits, a calibration experiment based on the excitation caused by a simulated monopulse current was performed. The results of the proposed calibration method and the calibration experiment are in good agreement.

  19. Synthesis and Structure of A Novel Caged Bicyclic Phosphate Flame Retardant

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A novel caged bicyclic phosphate flame retardant tri(1-oxo-2,6,7-trioxa-l-phosphabicyclo [2.2.2] octane-methyl) phosphate (Trimer) was synthesized from 1-oxo-4-hydroxymethyl-2,6,7-trioxa-l-phosphabicyclo [2.2.2] octane (PEPA) and phosphorus oxychloride in this paper.Its structure was characterized by elemental analysis, FTIR, 1H NMR, 31P NMR and X-ray diffraction analysis.

  20. Validation of an automated mite counter for Dermanyssus gallinae in experimental laying hen cages

    OpenAIRE

    Mul, Monique; van Riel, Johan; Meerburg, Bastiaan; Dicke, Marcel; George, David; Groot Koerkamp, Peter

    2015-01-01

    For integrated pest management (IPM) programs to be maximally effective, monitoring of the growth and decline of the pest populations is essential. Here, we present the validation results of a new automated monitoring device for the poultry red mite (Dermanyssus gallinae), a serious pest in laying hen facilities world-wide. This monitoring device (called an “automated mite counter”) was validated in experimental laying hen cages with live birds and a growing population of D. gallinae. This va...

  1. Cathodic cage nitriding of AISI 409 ferritic stainless steel with the addition of CH4

    Directory of Open Access Journals (Sweden)

    Rômulo Ribeiro Magalhães de Sousa

    2012-04-01

    Full Text Available AISI 409 ferritic stainless steel samples were nitrided using the cathodic cage plasma nitriding technique (CCPN, with the addition of methane to reduce chromium precipitation, increase hardness and wear resistance and reduce the presence of nitrides when compared to plasma carbonitriding. Microhardness profiles and X-Ray analysis confirm the formation of a very hard layer containing mainly ε-Fe3N and expanded ferrite phases.

  2. Template-directed synthesis of nets based upon octahemioctahedral cages that encapsulate catalytically active metalloporphyrins

    KAUST Repository

    Zhang, ZhenJie

    2012-01-18

    meso-Tetra(N-methyl-4-pyridyl)porphine tetratosylate (TMPyP) templates the synthesis of six new metal-organic materials by the reaction of benzene-1,3,5-tricarboxylate with transition metals, five of which exhibit HKUST-1 or tbo topology (M = Fe, Mn, Co, Ni, Mg). The resulting materials, porph@MOMs, selectively encapsulate the corresponding metalloporphyrins in octahemioctahedral cages and can serve as size-selective heterogeneous catalysts for oxidation of olefins. © 2011 American Chemical Society.

  3. Endotoxin concentration in poultry houses for laying hens kept in cages or in alternative housing systems

    OpenAIRE

    2011-01-01

    Abstract 1. Endotoxins as components of organic dust may have adverse effects on the respiratory health of workers in poultry buildings. The move towards more welfare-friendly housing systems for layers may increase worker exposure to air contaminants due to the use of litter. 2. The endotoxin concentrations in the inhalable fraction of airborne dust (below 100 ?m) from cage and alternative system henhouses (on-floor, free range and aviaries) were compared under both experiment...

  4. Boron cage compound materials and composites for shielding and absorbing neutrons

    Science.gov (United States)

    Bowen, III, Daniel E; Eastwood, Eric A

    2014-03-04

    Boron cage compound-containing materials for shielding and absorbing neutrons. The materials include BCC-containing composites and compounds. BCC-containing compounds comprise a host polymer and a BCC attached thereto. BCC-containing composites comprise a mixture of a polymer matrix and a BCC filler. The BCC-containing materials can be used to form numerous articles of manufacture for shielding and absorbing neutrons.

  5. Confocal Bioluminescence Imaging for Living Tissues with a Caged Substrate of Luciferin.

    Science.gov (United States)

    Hattori, Mitsuru; Kawamura, Genki; Kojima, Ryosuke; Kamiya, Mako; Urano, Yasuteru; Ozawa, Takeaki

    2016-06-21

    Fluorescence imaging can elucidate morphological organization and coordinal networks, but its background luminescence degrades the image contrast. Our confocal bioluminescence imaging system uses a luciferase caged substrate, with light passing through multipinhole arrays, causing bioluminescence at a focal plane. After a charge-coupled device camera captures luminescence, the imaging system acquires confocal images of multilayered cells with depth information, supporting quantitative analysis of spatial cellular localization in living tissues.

  6. Lewis acid fragmentation of a lithium aryloxide cage: generation of new heterometallic aluminium-lithium species.

    Science.gov (United States)

    Muñoz, Ma Teresa; Urbaneja, Carmen; Temprado, Manuel; Mosquera, Marta E G; Cuenca, Tomás

    2011-11-14

    Heterometallic aluminium-lithium species were prepared by the fragmentation reaction of the hexametallic cage compound [Li{2,6-(MeO)(2)C(6)H(3)O}](6) (1) with alkyl aluminium derivatives. Depending on the aluminium precursor, the species formed present different nuclearities in the solid state as shown by single crystal X-ray analysis. Spectroscopic and computational studies have been performed to study the nuclearity of the synthesized compounds in solution.

  7. A Self-Assembled Electro-Active M8L4 Cage Based on Tetrathiafulvalene Ligands

    Directory of Open Access Journals (Sweden)

    Sébastien Goeb

    2014-01-01

    Full Text Available Two self-assembled redox-active cages are presented. They are obtained by coordination-driven self-assembly of a tetra-pyridile tetrathiafulvalene ligand with cis-M(dppf(OTf2 (M = Pd or Pt; dppf = 1,1′-bis(diphenylphosphinoferrocene; OTf = trifluoromethane-sulfonate complexes. Both species are fully characterized and are constituted of 12 electro-active subunits that can be reversibly oxidized.

  8. In-electrode vs. on-electrode: ultrasensitive Faraday cage-type electrochemiluminescence immunoassay.

    Science.gov (United States)

    Guo, Zhiyong; Sha, Yuhong; Hu, Yufang; Wang, Sui

    2016-03-28

    A new-concept of an "in-electrode" Faraday cage-type electrochemiluminescence immunoassay (ECLIA) method for the ultrasensitive detection of neurotensin (NT) was reported with capture antibody (Ab1)-nanoFe3O4@graphene (GO) and detector antibody (Ab2)&N-(4-aminobutyl)-N-ethylisoluminol (ABEI)@GO, which led to about 1000-fold improvement in sensitivity by extending the Helmholtz plane (OHP) of the proposed electrode assembly effectively.

  9. High-pressure carbon dioxide uptake for porous organic cages: comparison of spectroscopic and manometric measurement techniques.

    Science.gov (United States)

    Hasell, Tom; Armstrong, Jayne A; Jelfs, Kim E; Tay, Feng H; Thomas, K Mark; Kazarian, Sergei G; Cooper, Andrew I

    2013-10-21

    A chemoselective spectroscopic method for measuring CO2 sorption isotherms at pressures up to 14 MPa (140 bar) is validated against manometric measurements and molecular simulations, giving insights into the preferred sorption sites in various crystalline porous organic cages.

  10. 9 CFR 82.10 - Interstate movement of vehicles, cages, coops, containers, troughs, and other equipment from a...

    Science.gov (United States)

    2010-01-01

    ... TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS EXOTIC NEWCASTLE DIS- EASE (END) AND CHLAMYDIOSIS Exotic Newcastle Disease (END) § 82.10 Interstate movement of vehicles, cages, coops,...

  11. Probing confinement resonances by photoionizing Xe inside a C60+ molecular cage

    Science.gov (United States)

    Phaneuf, R. A.; Kilcoyne, A. L. D.; Aryal, N. B.; Baral, K. K.; Thomas, C. M.; Esteves-Macaluso, D. A.; Lomsadze, R.; Gorczyca, T. W.; Ballance, C. P.; Manson, S. T.; Hasoglu, M. F.; Hellhund, J.; Schippers, S.; Müller, A.

    2014-05-01

    Double photoionization accompanied by loss of n C atoms (n = 0 , 2 , 4 , 6) was investigated by merging beams of Xe@C60+ ions and synchrotron radiation and measuring the yields of product ions. The giant 4 d dipole resonance of the caged Xe atom has a prominent signature in the cross section for these product channels, which together account for 6 . 2 +/- 1 . 4 of the total Xe 4 d oscillator strength of 10. Compared to that for a free Xe atom, the oscillator strength is redistributed in photon energy due to multipath interference of outgoing Xe 4 d photoelectron waves that may be transmitted or reflected by the spherical C60+ molecular cage, yielding so-called confinement resonances. The data are compared with an earlier measurement and with theoretical predictions for this single-molecule photoelectron interferometer system. Relativistic R-matrix calculations for the Xe atom in a spherical potential shell representing the fullerene cage show the sensitivity of the interference pattern to the molecular geometry.

  12. Distance Factors and Croatian Export Obstacles in the EU15: CAGE Approach

    Directory of Open Access Journals (Sweden)

    Helena Miloloža

    2015-07-01

    Full Text Available For long-term sustainability of any enterprise, it is required to observe each market separately and systematically modify business approach to prevailing conditions in each. However, adaptation to each market can be a complex affair that requires certain financial costs but ignoring distinguishing criteria leads to reduction in revenues and undermines long-term profitability. Time saving and cost-effectiveness can be achieved by application of The CAGE Distance Framework – a model that analysis all diversities between two or more countries. Croatia did not yet utilize the benefits that European Union membership provides nor did significantly improved its international business. It is obvious that Croatia faces difficulties in the strategic approach to prospective foreign markets. Therefore, emphasis of this article is on analysis and identification of the distinguishing factors between Croatia and the EU15 in order to facilitate and enhance cooperation among them in the future. Throughout the analysis of Croatian export from the beginning of the economic crisis, this article gives an overview of international collaboration among Croatia and the EU15 and comparative analysis by using The CAGE Distance Framework. This analysis has confirmed significant fluctuations, unexploited potential and problems of the Croatian economy in all dimensions of The CAGE model.

  13. Haematological and Biochemical Parameters during the Laying Period in Common Pheasant Hens Housed in Enhanced Cages

    Directory of Open Access Journals (Sweden)

    Petra Hrabčáková

    2014-01-01

    Full Text Available The development of selected haematological and biochemical parameters during the laying period was monitored in common pheasant hens housed in an enhanced cage system. The cages were enhanced by the addition of two perches and a shelter formed by strips of cloth hanging in the corner of the cage. The results showed significant changes in the haematological and biochemical parameters monitored during egg laying. At the time when laying capacity approached a maximum, a decrease was observed (P<0.05 in haematocrit, erythrocytes, and haemoglobin values, whereas monocytes, eosinophils, the heterophil/lymphocyte ratio, phosphorus, and calcium exhibited an increase (P<0.05. At the end of the laying period, an increase (P<0.05 was recorded in the count of leukocytes, heterophils, lymphocytes and basophils, the heterophil to lymphocyte ratio, and the concentrations of aspartate aminotransferase, cholesterol, phosphorus, and calcium, whereas lower values (P<0.05 were recorded for haematocrit and plasma total protein in comparison with the values of the indicators at the beginning of the laying period. The results provide new information about dynamic changes in selected haematological and biochemical parameters in clinically healthy common pheasant hens during the laying period.

  14. Survey of prevalence and control of ectoparasites in caged poultry in China.

    Science.gov (United States)

    Wang, F F; Wang, M; Xu, F R; Liang, D M; Pan, B L

    2010-12-11

    To investigate the prevalence and control of ectoparasites in China, 1200 questionnaires were delivered to caged commercial layer or parent hen keepers. Of the 860 respondents, 785 (91.3 per cent) claimed they found suspected ectoparasites in their birds and 833 samples were received. Ectoparasites of the species Dermanyssus gallinae, Ornithonyssus sylviarum or Menacanthuss stramineus were found in 736 (88.4 per cent) samples. For caged commercial layers, D gallinae was the most common ectoparasite (64.1 per cent). For caged parent hens, O sylviarum was the most common ectoparasite (46.9 per cent). Most bird keepers (95.0 per cent of commercial layer keepers and 74.9 per cent of parent hen keepers) used pyrethroids, organophosphates or other insecticides or acaricides to control ectoparasites. However, 34.6 per cent of layer keepers and 25.7 per cent of parent hen keepers did not re-treat their birds with insecticides or acaricides within two weeks after the first treatment. Sanitation procedures, including cleaning, washing and disinfection, were conducted in empty houses between flocks and on most commercial layer farms and parent hen farms. However, insecticides or acaricides were used in empty houses between flocks only in 24.8 per cent of commercial layer farms and in 36.1 per cent of parent hen farms.

  15. Corticosterone and fear behaviour in white and brown caged laying hens.

    Science.gov (United States)

    Fraisse, F; Cockrem, J F

    2006-04-01

    Physiological and behavioural measures of stress in caged hens on a commercial farm were compared between White Leghorn and brown Hyline strains, and between three tiers of cages. Blood and faecal samples were collected from undisturbed birds for corticosterone measurements. Plasma corticosterone responses to a stressor were measured by the collection of blood samples after 15, 30, and 60 min of a handling stressor. Tonic immobility and novel object tests were used to measure fear behaviour. Plasma corticosterone in undisturbed hens and faecal corticosterone did not differ between White Leghorn and brown Hyline hens, whereas the plasma corticosterone response to a handling stressor was greater in White Leghorns. The duration of tonic immobility, latency to first head movement and number of head movements in tonic immobility tests were greater in white than brown birds, whereas the number of inductions was less for tonic immobility tests. There were no differences between the strains in their responses to a novel object. There were no differences between tiers in plasma corticosterone or corticosterone responses or tonic immobility responses, and no consistent differences in responses of birds to a novel object. This is the first study in which plasma and faecal corticosterone concentrations and fear behaviour have been measured together in laying hens, and the first description of plasma corticosterone responses to handling over 60 min for caged laying hens on a commercial farm. The study has shown the value of measuring endocrine and behavioural variables together to provide objective data on characteristics of different strains of hens.

  16. Effects of Changing to Individually Ventilated Caging on Guinea Pigs (Cavia porcellus).

    Science.gov (United States)

    Giral, Marta; Armengol, Clara; Sánchez-Gómez, Sonia; Gavaldà, Amadeu

    2015-05-01

    The goal of this study was to evaluate the effect of changing to IVC housing on guinea pigs by recording several physiologic parameters in guinea pigs housed sequentially in open-top cages (OTC) and IVC. To register heart rate and locomotor activity, 10 male Dunkin-Hartley guinea pigs implanted with telemetric transmitters were moved from OTC to new, freshly prepared OTC or IVC and subsequently monitored by telemetry during the 4 d after the first cage change. Body weight and food consumption were measured twice during the study. Comparison of data from OTC- and IVC-housed guinea pigs showed no relevant differences in heart rate (mean ± 1 SD; 213 ± 10 bpm and 207 ± 9 bpm, respectively) at any time point. In contrast, locomotor activity varied: whereas activity during the first 4 h after the change of cage type was greater in IVC-housed animals, that during the following 24 h was greater in OTC but was similar between groups thereafter. Animals housed in OTC consumed more food than did those in IVC and, under both conditions, consumption was statistically related to body weight changes. Together, these results show that a change to IVC housing induced only transient increases in locomotor activity in guinea pigs without a marked increase in heart rate but with a decrease in food consumption. Because decreased food consumption was the only stress-associated sign during the 4-d observation, longer studies are needed to ascertain the importance of this finding.

  17. Novel approach to the behavioural characterization of inbred mice: automated home cage observations.

    Science.gov (United States)

    de Visser, L; van den Bos, R; Kuurman, W W; Kas, M J H; Spruijt, B M

    2006-08-01

    Here we present a newly developed tool for continuous recordings and analysis of novelty-induced and baseline behaviour of mice in a home cage-like environment. Aim of this study was to demonstrate the strength of this method by characterizing four inbred strains of mice, C57BL/6, DBA/2, C3H and 129S2/Sv, on locomotor activity. Strains differed in circadian rhythmicity, novelty-induced activity and the time-course of specific behavioural elements. For instance, C57BL/6 and DBA/2 mice showed a much faster decrease in activity over time than C3H and 129S2/Sv mice. Principal component analysis revealed two major factors within locomotor activity, which were defined as 'level of activity' and 'velocity/stops'. These factors were able to distinguish strains. Interestingly, mice that displayed high levels of activity in the initial phase of the home cage test were also highly active during an open-field test. Velocity and the number of stops during movement correlated positively with anxiety-related behaviour in the elevated plus maze. The use of an automated home cage observation system yields temporal changes in elements of locomotor activity with an advanced level of spatial resolution. Moreover, it avoids the confounding influence of human intervention and saves time-consuming human observations.

  18. In vivo antimicrobial activity of marbofloxacin against Pasteurella multocida in a tissue cage model in calves

    Directory of Open Access Journals (Sweden)

    Changfu eCao

    2015-07-01

    Full Text Available Marbofloxacin is a fluoroquinolone specially developed for use in veterinary medicine with broad-spectrum antibacterial activity. The objective of our study was to re-evaluate in vivo antimicrobial activity of marbofloxacin against Pasteurella multocida using subcutaneously implanted tissue cages in calves. Calves were infected by direct injection into tissue cages with Pasteurella multocida(type B, serotype 2, then intramuscularly received a range of marbofloxacin doses 24h after inoculation. The ratio of 24h area under the concentration-time curve divided by the minimum inhibitory concentration or the mutant prevention concentration (AUC24h/MIC or AUC24h/MPC was the pharmacokinetic-pharmacodynamic (PK/PD index that best described the effectiveness of marbofloxacin against Pasteurella multocida (R2=0.8514 by nonlinear regression analysis. Marbofloxacin exhibited a good antimicrobial activity in vivo. The levels of AUC24h/MIC and AUC24h/MPC that produced 50% (1.5log10CFU/mL reduction and 90% (3log10CFU/mL reduction of maximum response were 18.60h and 50.65h, 4.67h and 12.89h by using sigmoid Emax model WINNONLIN software, respectively. The in vivo PK/PD integrated methods by tissue cage model display the advantage of the evaluation of antimicrobial activity and the optimization of the dosage regimen for antibiotics in the presence of the host defenses, especially in target animal of veterinary interest.

  19. In vivo antimicrobial activity of marbofloxacin against Pasteurella multocida in a tissue cage model in calves.

    Science.gov (United States)

    Cao, Changfu; Qu, Ying; Sun, Meizhen; Qiu, Zhenzhen; Huang, Xianhui; Huai, Binbin; Lu, Yan; Zeng, Zhenling

    2015-01-01

    Marbofloxacin is a fluoroquinolone specially developed for use in veterinary medicine with broad-spectrum antibacterial activity. The objective of our study was to re-evaluate in vivo antimicrobial activity of marbofloxacin against Pasteurella multocida using subcutaneously implanted tissue cages in calves. Calves were infected by direct injection into tissue cages with P. multocida(type B, serotype 2), then intramuscularly received a range of marbofloxacin doses 24 h after inoculation. The ratio of 24 h area under the concentration-time curve divided by the minimum inhibitory concentration or the mutant prevention concentration (AUC24 h/MIC or AUC24 h/MPC) was the pharmacokinetic-pharmacodynamic (PK/PD) index that best described the effectiveness of marbofloxacin against P. multocida (R (2) = 0.8514) by non-linear regression analysis. Marbofloxacin exhibited a good antimicrobial activity in vivo. The levels of AUC24 h/MIC and AUC24 h/MPC that produced 50% (1.5log10 CFU/mL reduction) and 90% (3log10 CFU/mL reduction) of maximum response were 18.60 and 50.65 h, 4.67 and 12.89 h by using sigmoid Emax model WINNONLIN software, respectively. The in vivo PK/PD integrated methods by tissue cage model display the advantage of the evaluation of antimicrobial activity and the optimization of the dosage regimen for antibiotics in the presence of the host defenses, especially in target animal of veterinary interest.

  20. Structural and static electric response properties of highly symmetric lithiated silicon cages: theoretical predictions.

    Science.gov (United States)

    Koukaras, Emmanuel N; Zdetsis, Aristides D; Karamanis, Panaghiotis; Pouchan, Claude; Avramopoulos, Aggelos; Papadopoulos, Manthos G

    2012-04-15

    It is shown by density functional theory calculations that high symmetry silicon cages can be designed by coating with Li atoms. The resulting highly symmetric lithiated silicon cages (up to D(5d) symmetry) are low-lying true minima of the energy hypersurface with binding energies of the order of 4.6 eV per Si atom and moderate highest occupied molecular orbital-lowest unoccupied molecular orbital gaps. Moreover, relying on a systematic study of the electric response properties obtained by ab initio (Hartree-Fock, MP2, and configuration interaction singles (CIS)) and density functional (B3LYP, B2PLYP, and CAM-B3LYP) methods, it is shown that lithium coating has a large impact on the magnitude of their second hyperpolarizabilities resulting to highly hyperpolarizable species. Such hyperpolarizable character is directly connected to the increase in the density of the low-lying excited states triggered by the interaction between the Si cage and the surrounding Li atoms.

  1. Transdural retrieval of a retropulsed lumbar interbody cage: Technical case report.

    Science.gov (United States)

    Zaidi, Hasan Aqdas; Shah, Ashish; Kakarla, Udaya Kumar

    2016-01-01

    The purpose of this case report was to describe a novel method to retrieve a herniated lumbar interbody cage. Transforaminal lumbar interbody fusion (TLIF) is an increasingly popular method of spinal fixation and fusion. Unexpected retropulsion of an interbody is a rare event that can result in intractable pain or motor compromise necessitating surgical retrieval of the interbody. Both anterior and posterior approaches to removing migrated cages may be associated with significant surgical morbidity and mortality. A 60-year-old woman underwent an L4-S1 TLIF coupled with pedicle screw fixation at a previous hospital 5 years prior to admission. She noted sudden-onset bilateral lower extremity weakness and right-sided foot drop. Magnetic resonance imaging and radiographs were notable for purely centrally herniated interbody. A posterior, midline transdural approach was used to retrieve the interbody. Situated in between nerve rootlets to the ventral canal, this virgin corridor allowed us to easily visualize and protect neurological structures while safely retrieving the interbody. The patient experienced an immediate improvement in symptoms and was discharged on postoperative day 3. At 12-month follow-up, she had no evidence of cerebrospinal fluid (CSF) leak and had returned to normal activities of daily living. While the risk of CSF leak may be higher with a transdural approach, we maintain that avoiding unnecessary retraction of the nerve roots may outweigh this risk. To our knowledge, this is the first case report of a transdural approach for the retrieval of a retropulsed lumbar interbody cage.

  2. Emissions of ammonia, carbon dioxide and particulate matter from cage-free layer houses in California

    Science.gov (United States)

    Lin, Xingjun; Zhang, Ruihong; Jiang, Shumei; El-Mashad, Hamed; Xin, Hongwei

    2017-03-01

    Cage-free housing systems have attracted considerable attention in the United States recently as they provide more space and other resources (such as litter area, perches, and nest boxes) for hens and are considered to be more favorable from the standpoint of hen welfare. This study was carried out to quantify emissions of aerial ammonia (NH3), carbon dioxide (CO2) and particulate matter (PM10 and PM2.5) from cage-free layer houses in California and compare the values with those for other types of layer houses. Two commercial cage-free houses with 38,000 hens each were monitored from March 1, 2012 to April 1, 2013. Results show that NH3 and CO2 concentrations in the houses were affected by ventilation rate, which was largely influenced by ambient air temperature. The PM10 and PM2.5 concentrations in the houses depended on the activity of birds, ventilation rate and relative humidity of the ambient air. The average emission rates of NH3, CO2, PM10 and PM2.5 were 0.29, 89.9, 0.163 and 0.020 g d-1 hen-1, respectively. The NH3 emission rate determined in this study was higher than those of aviary houses. The PM10 and PM2.5 emission rates were higher than those reported for high-rise layer houses.

  3. Be12O12 Nano-cage as a Promising Catalyst for CO2 Hydrogenation

    Science.gov (United States)

    Zhu, Haiyan; Li, Yawei; Zhu, Guizhi; Su, Haibin; Chan, Siew Hwa; Sun, Qiang

    2017-01-01

    An efficient conversion of CO2 into valuable fuels and chemicals has been hotly pursued recently. Here, for the first time, we have explored a series of M12x12 nano-cages (M = B, Al, Be, Mg; X = N, P, O) for catalysis of CO2 to HCOOH. Two steps are identified in the hydrogenation process, namely, H2 activation to 2H*, and then 2H* transfer to CO2 forming HCOOH, where the barriers of two H* transfer are lower than that of the H2 activation reaction. Among the studied cages, Be12O12 is found to have the lowest barrier in the whole reaction process, showing two kinds of reaction mechanisms for 2H* (simultaneous transfer and a step-wise transfer with a quite low barrier). Moreover, the H2 activation energy barrier can be further reduced by introducing Al, Ga, Li, and Na to B12N12 cage. This study would provide some new ideas for the design of efficient cluster catalysts for CO2 reduction.

  4. The reaction process of firefly bioluminescence triggered by photolysis of caged-ATP.

    Science.gov (United States)

    Kageyama, Takeshi; Tanaka, Masatoshi; Sekiya, Takao; Ohno, Shin-Ya; Wada, Naohisa

    2011-01-01

    The reaction process of firefly bioluminescence was studied by photolyzing caged-ATP to adenosine triphosphate (ATP) within 100 ms. The intensity of luminescence increases markedly to reach a maximum within 1 s, maintains almost the same intensity up to 5 s and then decays monotonically. The rise γ(1) and decay γ(2) rate constants were determined to be about 5 s(-1) and 1 × 10(-2) s(-1), respectively, so as to phenomenologically fit the time course. A second luminescence peak appears after around 350 s. The dependence of the rate constants on the concentrations of reactants and a viscous reagent revealed that two kinds of reaction contribute the observed time course: (1) an intrinsic reaction by ATP photolyzed from caged-ATP that is already trapped in luciferase; and (2) a diffusion-controlled reaction by free ATP in the buffer solution outside luciferase. Numerical analysis based on reaction kinetics related γ(1) and γ(2) to the rate constants of a three-step reaction model, and accurately described the effects of concentration of reactants and a viscous reagent on the time courses of bioluminescence. Thus, it has been clearly concluded that the binding mode of caged-ATP at the catalytic center of luciferase is very different from that of ATP.

  5. Sublethal effects in caged rainbow trout during remedial activities in Lake Jaernsjoen

    Energy Technology Data Exchange (ETDEWEB)

    Blom, S.; Foerlin, L. [Goeteborg Univ. (Sweden). Dept. of Zoophysiology; Norrgren, L. [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Faculty of Veterinary Medicine, Dept. of Pathology

    1998-08-01

    Caging juvenile rainbow trout in the PCB polluted Lake Jaernsjoen in 1991 prior to remediation resulted in induction of liver ethoxyresorufin-O-deethylase (EROD) activity, liver lesions, skin lesions and fin erosions, all of which can be caused by subchronic exposure to PCB. During the remediation in 1993 and 1994, pronounced induction of the liver EROD, bile-duct proliferation and a relatively high incidence of necrotic hepatocytes were seen in the rainbow trout caged in Lake Jaernsjoen. The histopathological damage noted in the liver was reflected in changes in plasma ASAT activities. In 1996, two years after the remedial activities, the EROD activity was still slightly induced in caged rainbow trout in Jaernsjoen, but the fish showed no sign of histopathological changes. In addition, the liver EROD activity was induced in some sites downstream of Jaernsjoen. These results indicate a downstream transport of contaminants following the remedial action Special issue. The Jaernsjoen project, Sweden. Remediation of PCB-contaminated sediments. 50 refs, 4 figs, 6 tabs

  6. The light spot test: Measuring anxiety in mice in an automated home-cage environment.

    Science.gov (United States)

    Aarts, Emmeke; Maroteaux, Gregoire; Loos, Maarten; Koopmans, Bastijn; Kovačević, Jovana; Smit, August B; Verhage, Matthijs; Sluis, Sophie van der

    2015-11-01

    Behavioral tests of animals in a controlled experimental setting provide a valuable tool to advance understanding of genotype-phenotype relations, and to study the effects of genetic and environmental manipulations. To optimally benefit from the increasing numbers of genetically engineered mice, reliable high-throughput methods for comprehensive behavioral phenotyping of mice lines have become a necessity. Here, we describe the development and validation of an anxiety test, the light spot test, that allows for unsupervised, automated, high-throughput testing of mice in a home-cage system. This automated behavioral test circumvents bias introduced by pretest handling, and enables recording both baseline behavior and the behavioral test response over a prolonged period of time. We demonstrate that the light spot test induces a behavioral response in C57BL/6J mice. This behavior reverts to baseline when the aversive stimulus is switched off, and is blunted by treatment with the anxiolytic drug Diazepam, demonstrating predictive validity of the assay, and indicating that the observed behavioral response has a significant anxiety component. Also, we investigated the effectiveness of the light spot test as part of sequential testing for different behavioral aspects in the home-cage. Two learning tests, administered prior to the light spot test, affected the light spot test parameters. The light spot test is a novel, automated assay for anxiety-related high-throughput testing of mice in an automated home-cage environment, allowing for both comprehensive behavioral phenotyping of mice, and rapid screening of pharmacological compounds.

  7. Multiple biomarkers of pollution effects in caged mussels on the Greek coastline.

    Science.gov (United States)

    Tsangaris, C; Kormas, K; Strogyloudi, E; Hatzianestis, I; Neofitou, C; Andral, B; Galgani, F

    2010-04-01

    A suite of biomarkers was measured in caged mussels at areas impacted by different anthropogenic activities along the Greek coastline to assess biological effects of environmental pollution. Mussels were caged at coastal sites in the vicinity of major cities, in areas influenced by major industries, agricultural practices and in islands away from known sources of pollution. Biomarkers indicative of neurotoxicity (acetylcholinesterase, AchE), oxidative stress (catalase, CAT), phase II biotransformation of xenobiotics (glutathione S-transferase, GST), metal exposure (metallothioneins, MTs) and protein synthesis (RNA:DNA ratio) were measured to assess effects of various types of pollutants. AchE activity proved to be the most responsive biomarker with decreased values at sites influenced by agricultural, urban and industrial activities. Decreased CAT and GST activities and increased MTs levels were recorded at a number of anthropogenic-impacted sites. RNA:DNA ratio showed a biphasic response as both high and low values were found at impacted sites. Principal component analysis clearly distinguished sites receiving pollution inputs from non-polluted sites. The combination of the selected biomarkers used in caged mussels resulted useful in the assessment of the effects of environmental pollution.

  8. Dipole-induced band-gap reduction in an inorganic cage.

    Science.gov (United States)

    Lv, Yaokang; Cheng, Jun; Steiner, Alexander; Gan, Lihua; Wright, Dominic S

    2014-02-10

    Metal-doped polyoxotitanium cages are a developing class of inorganic compounds which can be regarded as nano- and sub-nano sized molecular relatives of metal-doped titania nanoparticles. These species can serve as models for the ways in which dopant metal ions can be incorporated into metal-doped titania (TiO2 ), a technologically important class of photocatalytic materials with broad applications in devices and pollution control. In this study a series of cobalt(II)-containing cages in the size range ca. 0.7-1.3 nm have been synthesized and structurally characterized, allowing a coherent study of the factors affecting the band gaps in well-defined metal-doped model systems. Band structure calculations are consistent with experimental UV/Vis measurements of the Tix Oy absorption edges in these species and reveal that molecular dipole moment can have a profound effect on the band gap. The observation of a dipole-induced band-gap decrease mechanism provides a potentially general design strategy for the formation of low band-gap inorganic cages.

  9. RESULTS OF TREATMENT OF CERVICAL DISCOPATHY WITH PEEK INTERBODY CAGES AT THREE LEVELS WITHOUT PLATE FIXATION

    Directory of Open Access Journals (Sweden)

    Amado González Moga

    Full Text Available ABSTRACT Objective: To present the results of treatment of patients with cervical discopathy by anterior cervical approach, discectomy and placement of a PEEK interbody cage without anterior plate fixation. Methods: Retrospective, cross-sectional study from March 2013 to March 2015. Sixteen patients with radiculopathy or clinical signs of myelopathy were included; all patients underwent cervical surgery through anterior approach, discectomy, and placement of PEEK cages on three levels. Decompression levels were determined according to the correlation between preoperative radiological and clinical findings. Results: Sixteen patients predominantly male were included, with mean age of 50 years at the onset of the condition. Ten patients had involvement of C4-C5, C5-C6, C6-C7 levels, and six patients C3-C4, C4-C5 and C5-C6. Fourteen patients had cervicobrachialgia and two myelopathy. The preoperative visual analog scale average was 8/10 and the average postoperative value at 6 months was 3/10. At 6 months, there was no radiological evidence of recurrence. One patient had non-fatal complications. Conclusions: The treatment of cervical discopathy by anterior approach with interbody fusion with PEEK cage on three levels, with no plate fixation seemed to be safe and effective with better long-term results in terms of pain and myelopathy. The clinical results compare favorably with other similar series and, most importantly, the complications associated with anterior fixation plate are avoided.

  10. Slotted cage resonator for high-field magnetic resonance imaging of rodents

    Energy Technology Data Exchange (ETDEWEB)

    Marrufo, O; Vasquez, F; Solis, S E; Rodriguez, A O, E-mail: arog@xanum.uam.mx [Departamento de Ingenieria Electrica, Universidad Autonoma Metropolitana Iztapalapa, Mexico, DF 09340 (Mexico)

    2011-04-20

    A variation of the high-frequency cavity resonator coil was experimentally developed according to the theoretical frame proposed by Mansfield in 1990. Circular slots were used instead of cavities to form the coil endplates and it was called the slotted cage resonator coil. The theoretical principles were validated via a coil equivalent circuit and also experimentally with a coil prototype. The radio frequency magnetic field, B1, produced by several coil configurations was numerically simulated using the finite-element approach to investigate their performances. A transceiver coil, 8 cm long and 7.6 cm in diameter, and composed of 4 circular slots with a 15 mm diameter on both endplates, was built to operate at 300 MHz and quadrature driven. Experimental results obtained with the slotted cage resonator coil were presented and showed very good agreement with the theoretical expectations for the resonant frequency as a function of the coil dimensions and slots. A standard birdcage coil was also built for performance comparison purposes. Phantom images were then acquired to compute the signal-to-noise ratio of both coils showing an important improvement of the slotted cage coil over the birdcage coil. The whole-body images of the mouse were also obtained showing high-quality images. Volume resonator coils can be reliably built following the physical principles of the cavity resonator design for high-field magnetic resonance imaging applications of rodents.

  11. Stocking densities of juvenile Brycon orthotaenia: production parameters and economic benefits in net cages

    Directory of Open Access Journals (Sweden)

    Aline de Assis Lago

    2014-07-01

    Full Text Available Developing a rearing technology requires the determination of the optimum stocking density. This study aimed to determine the best stocking density for Brycon orthotaenia juveniles grown in net cages, during the rearing phase. The research was conducted at the Experimental Farm of EPAMIG, in Felixlândia, Minas Gerais State, in the Três Marias Reservoir. 9,000 fingerlings were distributed into 12 net cages, 2 m3each, according to a completely randomized design with three replications and four different stocking densities (150, 300, 450, 600 fish m-3. Random samples were taken from each net cage, at the onset of the experiment and at 60 rearing days, to assess production parameters, specific growth rate and uniformity. We verified a positive linear relationship (p 0.05 for growth parameters, uniformity and final weight. It can be concluded that the density of 300 fish m-3 is the most suitable, because it provides higher net revenue, survival, and a good feed conversion.

  12. Does rearing laying hens in aviaries adversely affect long-term welfare following transfer to furnished cages?

    Directory of Open Access Journals (Sweden)

    Fernanda M Tahamtani

    Full Text Available This study tests the hypothesis that hens that are reared in aviaries but produce in furnished cages experience poorer welfare in production than hens reared in caged systems. This hypothesis is based on the suggestion that the spatial restriction associated with the transfer from aviaries to cages results in frustration or stress for the aviary reared birds. To assess the difference in welfare between aviary and cage reared hens in production, non-beak trimmed white leghorn birds from both rearing backgrounds were filmed at a commercial farm that used furnished cage housing. The videos were taken at 19 and 21 weeks of age, following the birds' transition to the production environment at 16 weeks. Videos were analysed in terms of the performance of aversion-related behaviour in undisturbed birds, comfort behaviour in undisturbed birds, and alert behaviour directed to a novel object in the home cage. A decrease in the performance of the former behaviour and increase in the performance of the latter two behaviours indicates improved welfare. The results showed that aviary reared birds performed more alert behaviour near to the object than did cage reared birds at 19 but not at 21 weeks of age (P = 0.03. Blood glucose concentrations did not differ between the treatments (P>0.10. There was a significant difference in mortality between treatments (P = 0.000, with more death in aviary reared birds (5.52% compared to cage birds (2.48%. The higher mortality of aviary-reared birds indicates a negative effect of aviary rearing on bird welfare, whereas the higher duration of alert behavior suggests a positive effect of aviary rearing.

  13. Does rearing laying hens in aviaries adversely affect long-term welfare following transfer to furnished cages?

    Science.gov (United States)

    Tahamtani, Fernanda M; Hansen, Tone Beate; Orritt, Rachel; Nicol, Christine; Moe, Randi O; Janczak, Andrew M

    2014-01-01

    This study tests the hypothesis that hens that are reared in aviaries but produce in furnished cages experience poorer welfare in production than hens reared in caged systems. This hypothesis is based on the suggestion that the spatial restriction associated with the transfer from aviaries to cages results in frustration or stress for the aviary reared birds. To assess the difference in welfare between aviary and cage reared hens in production, non-beak trimmed white leghorn birds from both rearing backgrounds were filmed at a commercial farm that used furnished cage housing. The videos were taken at 19 and 21 weeks of age, following the birds' transition to the production environment at 16 weeks. Videos were analysed in terms of the performance of aversion-related behaviour in undisturbed birds, comfort behaviour in undisturbed birds, and alert behaviour directed to a novel object in the home cage. A decrease in the performance of the former behaviour and increase in the performance of the latter two behaviours indicates improved welfare. The results showed that aviary reared birds performed more alert behaviour near to the object than did cage reared birds at 19 but not at 21 weeks of age (P = 0.03). Blood glucose concentrations did not differ between the treatments (P>0.10). There was a significant difference in mortality between treatments (P = 0.000), with more death in aviary reared birds (5.52%) compared to cage birds (2.48%). The higher mortality of aviary-reared birds indicates a negative effect of aviary rearing on bird welfare, whereas the higher duration of alert behavior suggests a positive effect of aviary rearing.

  14. Persistence of fecal shedding of Salmonella Enteritidis by experimentally infected laying hens housed in conventional or enriched cages.

    Science.gov (United States)

    Gast, Richard K; Guraya, Rupa; Jones, Deana R; Anderson, Kenneth E

    2015-07-01

    Salmonella Enteritidis can be deposited inside eggs laid by infected hens, so the prevalence of this pathogen in commercial egg-producing flocks is an important risk factor for human illness. Opportunities for the introduction, transmission, and persistence of salmonellae in poultry are potentially influenced by flock housing and management systems. Animal welfare concerns have spurred the development of alternatives to traditional cage-based housing. However, the consequences of poultry housing systems for food safety have not been fully resolved by prior research. The present study assessed the effects of two different housing systems (conventional cages and colony cages enriched with perching and nesting areas) on the persistence of fecal shedding of Salmonella Enteritidis by groups of experimentally infected laying hens. In each of two trials, 136 hens were distributed among cages of both housing systems and orally inoculated with doses of 10(8) cfu of Salmonella Enteritidis (phage type 13a in one trial and phage type 4 in the other). At weekly intervals, samples of voided feces were collected from beneath each cage and cultured to detect Salmonella Enteritidis. Fecal shedding of Salmonella Enteritidis was detected for up to 8 wk post-inoculation by hens housed in enriched colony cages and 10 wk by hens housed in conventional cages. For both trials combined, the frequency of positive fecal cultures was significantly (P Salmonella Enteritidis can differ between conventional and enriched cage-based production systems, although this effect does not necessarily translate into a corresponding difference in the longer-term persistence of fecal shedding.

  15. Exogenous control over intracellular acidification: Enhancement via proton caged compounds coupled to gold nanoparticles and an alternative pathway with DMSO

    Directory of Open Access Journals (Sweden)

    Marilena Carbone

    2016-03-01

    In the process of searching a pathway to augment the intracellular uptake of proton caged compounds, we probed the association of 1-(2-nitrophenyl-ethylhexadecyl sulfonate (HDNS with DMSO, an agent to enhance the membrane permeability. We found out a different UV-induced protonation mechanism that opens up to new conduits of employing of proton caged compounds. Here, we report the infrared data we collected in this set of experiments.

  16. THE OPTIMIZATION OF PLUSH YARNS BULKING PROCESS

    Directory of Open Access Journals (Sweden)

    VINEREANU Adam

    2014-05-01

    Full Text Available This paper presents the experiments that were conducted on the installation of continuous bulking and thermofixing “SUPERBA” type TVP-2S for optimization of the plush yarns bulking process. There were considered plush yarns Nm 6.5/2, made of the fibrous blend of 50% indigenous wool sort 41 and 50% PES. In the first stage, it performs a thermal treatment with a turboprevaporizer at a temperature lower than thermofixing temperature, at atmospheric pressure, such that the plush yarns - deposed in a freely state on a belt conveyor - are uniformly bulking and contracting. It was followed the mathematical modeling procedure, working with a factorial program, rotatable central composite type, and two independent variables. After analyzing the parameters that have a direct influence on the bulking degree, there were selected the pre-vaporization temperature (coded x1,oC and the velocity of belt inside pre-vaporizer (coded x 2, m/min. As for the dependent variable, it was chosen the plush yarn diameter (coded y, mm. There were found the coordinates of the optimal point, and then this pair of values was verified in practice. These coordinates are: x1optim= 90oC and x 2optim= 6.5 m/min. The conclusion is that the goal was accomplished: it was obtained a good cover degree f or double-plush carpets by reducing the number of tufts per unit surface.

  17. The Bulk Multicore Architecture for Improved Programmability

    Science.gov (United States)

    2009-12-01

    dependences bundled together. In the Bulk Multi- core, the log must store only the total order of chunk commits, an approach we call DeLorean .13 The...ACM Press, New York, 2007, 69–80. 13. Montesinos, P., Ceze, L., and Torrellas, J. DeLorean : Recording and deterministically replaying shared

  18. Failure by fracture in bulk metal forming

    DEFF Research Database (Denmark)

    Silva, C.M.A.; Alves, Luis M.; Nielsen, Chris Valentin

    2015-01-01

    This paper revisits formability in bulk metal forming in the light of fundamental concepts of plasticity,ductile damage and crack opening modes. It proposes a new test to appraise the accuracy, reliability and validity of fracture loci associated with crack opening by tension and out-of-plane she...

  19. Bulk viscosity effects on ultrasonic thermoacoustic instability

    Science.gov (United States)

    Lin, Jeffrey; Scalo, Carlo; Hesselink, Lambertus

    2016-11-01

    We have carried out unstructured fully-compressible Navier-Stokes simulations of a minimal-unit traveling-wave ultrasonic thermoacoustic device in looped configuration. The model comprises a thermoacoustic stack with 85% porosity and a tapered area change to suppress the fundamental standing-wave mode. A bulk viscosity model, which accounts for vibrational and rotational molecular relaxation effects, is derived and implemented via direct modification of the viscous stress tensor, τij ≡ 2 μSij +λ/2 μ ∂uk/∂xk δij , where the bulk viscosity is defined by μb ≡ λ +2/3 μ . The effective bulk viscosity coefficient accurately captures acoustic absorption from low to high ultrasonic frequencies and matches experimental wave attenuation rates across five decades. Using pressure-based similitude, the model was downscaled from total length L = 2 . 58 m to 0 . 0258 m, corresponding to the frequency range f = 242 - 24200 Hz, revealing the effects of bulk viscosity and direct modification of the thermodynamic pressure. Simulations are carried out to limit cycle and exhibit growth rates consistent with linear stability analyses, based on Rott's theory.

  20. Forming of bulk metallic glass microcomponents

    DEFF Research Database (Denmark)

    Wert, John A.; Thomsen, Christian; Jensen, Rune Debel

    2009-01-01

    The present article considers forward extrusion, closed-die forging and backward extrusion processes for fabrication of individual microcomponents from two bulk metallic glass (BMG) compositions: Mg60Cu30Y10 and Zr44Cu40Ag8Al8. Two types of tooling were used in the present work: relatively massive...

  1. Polymer-fullerene bulk heterojunction solar cells

    NARCIS (Netherlands)

    Janssen, RAJ; Hummelen, JC; Saricifti, NS

    2005-01-01

    Nanostructured phase-separated blends, or bulk heterojunctions, of conjugated Polymers and fullerene derivatives form a very attractive approach to large-area, solid-state organic solar cells.The key feature of these cells is that they combine easy, processing from solution on a variety of substrate

  2. Fluctuating brane in a dilatonic bulk

    CERN Document Server

    Brax, P; Rodríguez-Martinez, M; Brax, Philippe; Langlois, David; Rodriguez-Martinez, Maria

    2003-01-01

    We consider a cosmological brane moving in a static five-dimensional bulk spacetime endowed with a scalar field whose potential is exponential. After studying various cosmological behaviours for the homogeneous background, we investigate the fluctuations of the brane that leave spacetime unaffected. A single mode embodies these fluctuations and obeys a wave equation which we study for bouncing and ever-expanding branes.

  3. Longitudinal bulk a coustic mass sensor

    DEFF Research Database (Denmark)

    Hales, Jan Harry; Teva, Jordi; Boisen, Anja;

    2009-01-01

    Design, fabrication and characterization, in terms of mass sensitivity, is presented for a polycrystalline silicon longitudinal bulk acoustic cantilever. The device is operated in air at 51 MHz, resulting in a mass sensitivity of 100 HZ/fg (1 fg = 10{su−15 g). The initial characterization...

  4. A Stereoscopic Look into the Bulk

    CERN Document Server

    Czech, Bartlomiej; McCandlish, Samuel; Mosk, Benjamin; Sully, James

    2016-01-01

    We present the foundation for a holographic dictionary with depth perception. The dictionary consists of natural CFT operators whose duals are simple, diffeomorphism-invariant bulk operators. The CFT operators of interest are the "OPE blocks," contributions to the OPE from a single conformal family. In holographic theories, we show that the OPE blocks are dual at leading order in 1/N to integrals of effective bulk fields along geodesics or homogeneous minimal surfaces in anti-de Sitter space. One widely studied example of an OPE block is the modular Hamiltonian, which is dual to the fluctuation in the area of a minimal surface. Thus, our operators pave the way for generalizing the Ryu-Takayanagi relation to other bulk fields. Although the OPE blocks are non-local operators in the CFT, they admit a simple geometric description as fields in kinematic space--the space of pairs of CFT points. We develop the tools for constructing local bulk operators in terms of these non-local objects. The OPE blocks also allow ...

  5. Wire-bottom versus solid-bottom rodent caging issues important to scientists and laboratory animal science specialists.

    Science.gov (United States)

    Stark, D M

    2001-11-01

    Recent emphasis in the National Research Council's Guide for the Care and Use of Laboratory Animals and by the Association for Assessment and Accreditation of Laboratory Animal Care, International, related to the availability of bedding in rodent cages raises regulatory and accreditation issues in the toxicology-laboratory setting. This article reviews the results of a recent survey of 12 United States-based pharmaceutical and contract toxicology laboratories. The perceived benefits and issues related to the use of wire-bottom and bedded caging for rodent studies are presented. The 1999 survey showed that more than 80% of the rodents in surveyed toxicology facilities were housed in wire-bottom cages. Long-term budget expenses related to supplies and waste disposal are assessed. Considerable short-term and long-term costs to programs would be associated with a change from wire-bottom to solid-bottom caging. A review of the past and recent literature related to animal preferences and cage-associated animal lesions is included. The importance of IACUC review of caging chosen by the investigative staff is emphasized.

  6. Microbiota composition of simultaneously colonized mice housed under either a gnotobiotic isolator or individually ventilated cage regime

    Science.gov (United States)

    Lundberg, Randi; Bahl, Martin I.; Licht, Tine R.; Toft, Martin F.; Hansen, Axel K.

    2017-01-01

    Germ-free rodents colonized with microbiotas of interest are used for host-microbiota investigations and for testing microbiota-targeted therapeutic candidates. Traditionally, isolators are used for housing such gnotobiotic rodents due to optimal protection from the environment, but research groups focused on the microbiome are increasingly combining or substituting isolator housing with individually ventilated cage (IVC) systems. We compared the effect of housing systems on the gut microbiota composition of germ-free mice colonized with a complex microbiota and housed in either multiple IVC cages in an IVC facility or in multiple open-top cages in an isolator during three generations and five months. No increase in bacterial diversity as assessed by 16S rRNA gene sequencing was observed in the IVC cages, despite not applying completely aseptic cage changes. The donor bacterial community was equally represented in both housing systems. Time-dependent clustering between generations was observed in both systems, but was strongest in the IVC cages. Different relative abundance of a Rikenellaceae genus contributed to separate clustering of the isolator and IVC communities. Our data suggest that complex microbiotas are protected in IVC systems, but challenges related to temporal dynamics should be addressed. PMID:28169374

  7. Porous biodegradable lumbar interbody fusion cage design and fabrication using integrated global-local topology optimization with laser sintering.

    Science.gov (United States)

    Kang, Heesuk; Hollister, Scott J; La Marca, Frank; Park, Paul; Lin, Chia-Ying

    2013-10-01

    Biodegradable cages have received increasing attention for their use in spinal procedures involving interbody fusion to resolve complications associated with the use of nondegradable cages, such as stress shielding and long-term foreign body reaction. However, the relatively weak initial material strength compared to permanent materials and subsequent reduction due to degradation may be problematic. To design a porous biodegradable interbody fusion cage for a preclinical large animal study that can withstand physiological loads while possessing sufficient interconnected porosity for bony bridging and fusion, we developed a multiscale topology optimization technique. Topology optimization at the macroscopic scale provides optimal structural layout that ensures mechanical strength, while optimally designed microstructures, which replace the macroscopic material layout, ensure maximum permeability. Optimally designed cages were fabricated using solid, freeform fabrication of poly(ε-caprolactone) mixed with hydroxyapatite. Compression tests revealed that the yield strength of optimized fusion cages was two times that of typical human lumbar spine loads. Computational analysis further confirmed the mechanical integrity within the human lumbar spine, although the pore structure locally underwent higher stress than yield stress. This optimization technique may be utilized to balance the complex requirements of load-bearing, stress shielding, and interconnected porosity when using biodegradable materials for fusion cages.

  8. Integration of bulk piezoelectric materials into microsystems

    Science.gov (United States)

    Aktakka, Ethem Erkan

    Bulk piezoelectric ceramics, compared to deposited piezoelectric thin-films, provide greater electromechanical coupling and charge capacity, which are highly desirable in many MEMS applications. In this thesis, a technology platform is developed for wafer-level integration of bulk piezoelectric substrates on silicon, with a final film thickness of 5-100microm. The characterized processes include reliable low-temperature (200°C) AuIn diffusion bonding and parylene bonding of bulk-PZT on silicon, wafer-level lapping of bulk-PZT with high-uniformity (+/-0.5microm), and low-damage micro-machining of PZT films via dicing-saw patterning, laser ablation, and wet-etching. Preservation of ferroelectric and piezoelectric properties is confirmed with hysteresis and piezo-response measurements. The introduced technology offers higher material quality and unique advantages in fabrication flexibility over existing piezoelectric film deposition methods. In order to confirm the preserved bulk properties in the final film, diaphragm and cantilever beam actuators operating in the transverse-mode are designed, fabricated and tested. The diaphragm structure and electrode shapes/sizes are optimized for maximum deflection through finite-element simulations. During tests of fabricated devices, greater than 12microm PP displacement is obtained by actuation of a 1mm2 diaphragm at 111kHz with management IC, which incorporates a supply-independent bias circuitry, an active diode for low-dropout rectification, a bias-flip system for higher efficiency, and a trickle battery charger. The overall system does not require a pre-charged battery, and has power consumption of sleep-mode (simulated). Under lg vibration at 155Hz, a 70mF ultra-capacitor is charged from OV to 1.85V in 50 minutes.

  9. 46 CFR 148.04-23 - Unslaked lime in bulk.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Unslaked lime in bulk. 148.04-23 Section 148.04-23... HAZARDOUS MATERIALS IN BULK Special Additional Requirements for Certain Material § 148.04-23 Unslaked lime in bulk. (a) Unslaked lime in bulk must be transported in unmanned, all steel, double-hulled...

  10. The influence of fish cage aquaculture on pelagic carbon flow and water chemistry in tidally dominated mangrove estuaries of peninsular Malaysia.

    Science.gov (United States)

    Alongi, D M; Chong, V C; Dixon, P; Sasekumar, A; Tirendi, F

    2003-05-01

    The impact of floating net cages culturing the seabass, Lates calcarifer, on planktonic processes and water chemistry in two heavily used mangrove estuaries in Malaysia was examined. Concentrations of dissolved inorganic and particulate nutrients were usually greater in cage vs. adjacent (approximately 100 m) non-cage waters, although most variability in water-column chemistry related to water depth and tides. There were few consistent differences in plankton abundance, production or respiration between cage and non-cage sites. Rates of primary production were low compared with rates of pelagic mineralization reflecting high suspended loads coupled with large inputs of organic matter from mangrove forests, fishing villages, fish cages, pig farms and other industries within the catchment. Our preliminary sampling did not reveal any large-scale eutrophication due to the cages. A crude estimate of the contribution of fish cage inputs to the estuaries shows that fish cages contribute only approximately 2% of C but greater percentages of N (32-36%) and P (83-99%) to these waters relative to phytoplankton and mangrove inputs. Isolating and detecting impacts of cage culture in such heavily used waterways--a situation typical of most mangrove estuaries in Southeast Asia--are constrained by a background of large, highly variable fluxes of organic material derived from extensive mangrove forests and other human activities.

  11. Towards a reconstruction of general bulk metrics

    Science.gov (United States)

    Engelhardt, Netta; Horowitz, Gary T.

    2017-01-01

    We prove that the metric of a general holographic spacetime can be reconstructed (up to an overall conformal factor) from distinguished spatial slices—‘light-cone cuts’—of the conformal boundary. Our prescription is covariant and applies to bulk points in causal contact with the boundary. Furthermore, we describe a procedure for determining the light-cone cuts corresponding to bulk points in the causal wedge of the boundary in terms of the divergences of correlators in the dual field theory. Possible extensions for determining the conformal factor and including the cuts of points outside of the causal wedge are discussed. We also comment on implications for subregion/subregion duality.

  12. Modeling direct interband tunneling. I. Bulk semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Andrew, E-mail: pandrew@ucla.edu [Department of Electrical Engineering, University of California, Los Angeles, Los Angeles, California 90095 (United States); Chui, Chi On [Department of Electrical Engineering, University of California, Los Angeles, Los Angeles, California 90095 (United States); California NanoSystems Institute, University of California, Los Angeles, Los Angeles, California 90095 (United States)

    2014-08-07

    Interband tunneling is frequently studied using the semiclassical Kane model, despite uncertainty about its validity. Revisiting the physical basis of this formula, we find that it neglects coupling to other bands and underestimates transverse tunneling. As a result, significant errors can arise at low and high fields for small and large gap materials, respectively. We derive a simple multiband tunneling model to correct these defects analytically without arbitrary parameters. Through extensive comparison with band structure and quantum transport calculations for bulk InGaAs, InAs, and InSb, we probe the accuracy of the Kane and multiband formulas and establish the superiority of the latter. We also show that the nonlocal average electric field should be used when applying either of these models to nonuniform potentials. Our findings are important for efficient analysis and simulation of bulk semiconductor devices involving tunneling.

  13. Multilayer Integrated Film Bulk Acoustic Resonators

    CERN Document Server

    Zhang, Yafei

    2013-01-01

    Multilayer Integrated Film Bulk Acoustic Resonators mainly introduces the theory, design, fabrication technology and application of a recently developed new type of device, multilayer integrated film bulk acoustic resonators, at the micro and nano scale involving microelectronic devices, integrated circuits, optical devices, sensors and actuators, acoustic resonators, micro-nano manufacturing, multilayer integration, device theory and design principles, etc. These devices can work at very high frequencies by using the newly developed theory, design, and fabrication technology of nano and micro devices. Readers in fields of IC, electronic devices, sensors, materials, and films etc. will benefit from this book by learning the detailed fundamentals and potential applications of these advanced devices. Prof. Yafei Zhang is the director of the Ministry of Education’s Key Laboratory for Thin Films and Microfabrication Technology, PRC; Dr. Da Chen was a PhD student in Prof. Yafei Zhang’s research group.

  14. Portable design rules for bulk CMOS

    Science.gov (United States)

    Griswold, T. W.

    1982-01-01

    It is pointed out that for the past several years, one school of IC designers has used a simplified set of nMOS geometric design rules (GDR) which is 'portable', in that it can be used by many different nMOS manufacturers. The present investigation is concerned with a preliminary set of design rules for bulk CMOS which has been verified for simple test structures. The GDR are defined in terms of Caltech Intermediate Form (CIF), which is a geometry-description language that defines simple geometrical objects in layers. The layers are abstractions of physical mask layers. The design rules do not presume the existence of any particular design methodology. Attention is given to p-well and n-well CMOS processes, bulk CMOS and CMOS-SOS, CMOS geometric rules, and a description of the advantages of CMOS technology.

  15. Fully antisymmetrised dynamics for bulk fermion systems

    CERN Document Server

    Vantournhout, Klaas

    2011-01-01

    The neutron star's crust and mantel are typical examples of non-uniform bulk systems with spacial localisations. When modelling such systems at low temperatures, as is the case in the crust, one has to work with antisymmetrised many-body states to get the correct fermion behaviour. Fermionic molecular dynamics, which works with an antisymmetrised product of localised wave packets, should be an appropriate choice. Implementing periodic boundary conditions into the fermionic molecular dynamics formalism would allow the study of the neutron star's crust as a bulk quantum system. Unfortunately, the antisymmetrisation is a non-local entanglement which reaches far out of the periodically repeated unit cell. In this proceeding, we give a brief overview how periodic boundary conditions and fermionic molecular dynamics can be combined without truncating the long-range many-body correlation induced by the antisymmetry of the many-body state.

  16. Bulk and shear viscosity in Hagedorn fluid

    Energy Technology Data Exchange (ETDEWEB)

    Tawfik, A.; Wahba, M. [Egyptian Center for Theoretical Physics (ECTP), MTI University, Faculty of Engineering, Cairo (Egypt)

    2010-11-15

    Assuming that the Hagedorn fluid composed of known particles and resonances with masses m <2 GeV obeys the first-order theory (Eckart) of relativistic fluid, we discuss the transport properties of QCD confined phase. Based on the relativistic kinetic theory formulated under the relaxation time approximation, expressions for bulk and shear viscosity in thermal medium of hadron resonances are derived. The relaxation time in the Hagedorn dynamical fluid exclusively takes into account the decay and eventually van der Waals processes. We comment on the in-medium thermal effects on bulk and shear viscosity and averaged relaxation time with and without the excluded-volume approach. As an application of these results, we suggest the dynamics of heavy-ion collisions, non-equilibrium thermodynamics and the cosmological models, which require thermo- and hydro-dynamics equations of state. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  17. Bulk and Shear Viscosity in Hagedorn Fluid

    CERN Document Server

    Tawfik, A

    2010-01-01

    Assuming that the Hagedorn fluid composed of known particles and resonances with masses $m<2\\,$GeV obeys the {\\it first-order} theory (Eckart) of relativistic fluid, we discuss the transport properties of QCD confined phase. Based on the relativistic kinetic theory formulated under the relaxation time approximation, expressions for bulk and shear viscosity in thermal medium are derived. The relaxation time in the Hagedorn dynamical fluid exclusively takes into account the decay and eventually van der Waals processes. We comment on the {\\it in-medium} thermal effects on bulk and shear viscosities and averaged relaxation time with and without the excluded-volume approach. As an application of these results, we suggest the dynamics of heavy-ion collisions, non-equlibrium thermodynamics and the cosmological models, which require thermo and hydrodynamics equations of state.

  18. Microfabricated bulk wave acoustic bandgap device

    Science.gov (United States)

    Olsson, Roy H.; El-Kady, Ihab F.; McCormick, Frederick; Fleming, James G.; Fleming, Carol

    2010-06-08

    A microfabricated bulk wave acoustic bandgap device comprises a periodic two-dimensional array of scatterers embedded within the matrix material membrane, wherein the scatterer material has a density and/or elastic constant that is different than the matrix material and wherein the periodicity of the array causes destructive interference of the acoustic wave within an acoustic bandgap. The membrane can be suspended above a substrate by an air or vacuum gap to provide acoustic isolation from the substrate. The device can be fabricated using microelectromechanical systems (MEMS) technologies. Such microfabricated bulk wave phononic bandgap devices are useful for acoustic isolation in the ultrasonic, VHF, or UHF regime (i.e., frequencies of order 1 MHz to 10 GHz and higher, and lattice constants of order 100 .mu.m or less).

  19. Depleted Bulk Heterojunction Colloidal Quantum Dot Photovoltaics

    KAUST Repository

    Barkhouse, D. Aaron R.

    2011-05-26

    The first solution-processed depleted bulk heterojunction colloidal quantum dot solar cells are presented. The architecture allows for high absorption with full depletion, thereby breaking the photon absorption/carrier extraction compromise inherent in planar devices. A record power conversion of 5.5% under simulated AM 1.5 illumination conditions is reported. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. On bulk viscosity and moduli decay

    OpenAIRE

    M. Laine

    2010-01-01

    This pedagogically intended lecture, one of four under the header "Basics of thermal QCD", reviews an interesting relationship, originally pointed out by Bodeker, that exists between the bulk viscosity of Yang-Mills theory (of possible relevance to the hydrodynamics of heavy ion collision experiments) and the decay rate of scalar fields coupled very weakly to a heat bath (appearing in some particle physics inspired cosmological scenarios). This topic serves, furthermore, as a platform on whic...

  1. Depleted bulk heterojunction colloidal quantum dot photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Barkhouse, D.A.R. [Department of Electrical and Computer Engineering, University of Toronto, 10 King' s College Road, Toronto, Ontario M5S 3G4 (Canada); IBM Thomas J. Watson Research Center, Kitchawan Road, Yorktown Heights, NY, 10598 (United States); Debnath, Ratan; Kramer, Illan J.; Zhitomirsky, David; Levina, Larissa; Sargent, Edward H. [Department of Electrical and Computer Engineering, University of Toronto, 10 King' s College Road, Toronto, Ontario M5S 3G4 (Canada); Pattantyus-Abraham, Andras G. [Department of Electrical and Computer Engineering, University of Toronto, 10 King' s College Road, Toronto, Ontario M5S 3G4 (Canada); Quantum Solar Power Corporation, 1055 W. Hastings, Ste. 300, Vancouver, BC, V6E 2E9 (Canada); Etgar, Lioz; Graetzel, Michael [Laboratory for Photonics and Interfaces, Institute of Chemical Sciences and Engineering, School of Basic Sciences, Swiss Federal Institute of Technology, CH-1015 Lausanne (Switzerland)

    2011-07-26

    The first solution-processed depleted bulk heterojunction colloidal quantum dot solar cells are presented. The architecture allows for high absorption with full depletion, thereby breaking the photon absorption/carrier extraction compromise inherent in planar devices. A record power conversion of 5.5% under simulated AM 1.5 illumination conditions is reported. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  2. Effects of bulk viscosity on cosmological evolution

    CERN Document Server

    Pimentel, L O; Pimentel, L O; Diaz-Rivera, L M

    1994-01-01

    Abstract:The effect of bulk viscisity on the evolution of the homogeneous and isotropic cosmological models is considered. Solutions are found, with a barotropic equation of state, and a viscosity coefficient that is proportional to a power of the energy density of the universe. For flat space, power law expansions, related to extended inflation are found as well as exponential solutions, related to old inflation; also a solution with expansion that is an exponential of an exponential of the time is found.

  3. Raman characterization of bulk ferromagnetic nanostructured graphite

    Energy Technology Data Exchange (ETDEWEB)

    Pardo, Helena, E-mail: hpardo@fq.edu.uy [Centro NanoMat, Polo Tecnologico de Pando, Facultad de Quimica, Universidad de la Republica, Cno. Aparicio Saravia s/n, 91000, Pando, Canelones (Uruguay); Crystallography, Solid State and Materials Laboratory (Cryssmat-Lab), DETEMA, Facultad de Quimica, Universidad de la Republica, Gral. Flores 2124, P.O. Box 1157, Montevideo (Uruguay); Divine Khan, Ngwashi [Mantfort University, Leicester (United Kingdom); Faccio, Ricardo [Centro NanoMat, Polo Tecnologico de Pando, Facultad de Quimica, Universidad de la Republica, Cno. Aparicio Saravia s/n, 91000, Pando, Canelones (Uruguay); Crystallography, Solid State and Materials Laboratory (Cryssmat-Lab), DETEMA, Facultad de Quimica, Universidad de la Republica, Gral. Flores 2124, P.O. Box 1157, Montevideo (Uruguay); Araujo-Moreira, F.M. [Grupo de Materiais e Dispositivos-CMDMC, Departamento de Fisica e Engenharia Fisica, UFSCar, Caixa Postal 676, 13565-905, Sao Carlos SP (Brazil); Fernandez-Werner, Luciana [Centro NanoMat, Polo Tecnologico de Pando, Facultad de Quimica, Universidad de la Republica, Cno. Aparicio Saravia s/n, 91000, Pando, Canelones (Uruguay); Crystallography, Solid State and Materials Laboratory (Cryssmat-Lab), DETEMA, Facultad de Quimica, Universidad de la Republica, Gral. Flores 2124, P.O. Box 1157, Montevideo (Uruguay)

    2012-08-15

    Raman spectroscopy was used to characterize bulk ferromagnetic graphite samples prepared by controlled oxidation of commercial pristine graphite powder. The G:D band intensity ratio, the shape and position of the 2D band and the presence of a band around 2950 cm{sup -1} showed a high degree of disorder in the modified graphite sample, with a significant presence of exposed edges of graphitic planes as well as a high degree of attached hydrogen atoms.

  4. Modeling of Microimprinting of Bulk Metallic Glasses

    Institute of Scientific and Technical Information of China (English)

    Ming CHENG; John A. Wert

    2006-01-01

    A finite element analysis (FEA) model has been developed to analyze microimprinting of bulk metallic glasses (BMG) near the glass transition temperature (Tg). The results reveal an approximately universal imprinting response for BMG, independent of surface feature length scale. The scale-independent nature of BMG imprinting derives from the flow characteristics of BMG in the temperature range above Tg. It also shows that the lubrication condition has a mild influence on BMG imprinting in the temperature range above Tg.

  5. Pseudo-Riemannian Universe from Euclidean bulk

    CERN Document Server

    Vasilić, Milovan

    2015-01-01

    I develop the idea that our world is a brane-like object embedded in Euclidean bulk. In its ground state, the brane constituent matter is assumed to be homogeneous and isotropic, and of negligible influence on the bulk geometry. No action functional is initially specified. Instead, the brane dynamics is derived from the universally valid stress-energy conservation equations. The present work studies the cosmology of a $3$-sphere in the $5$-dimensional Euclidean bulk. It is shown that the conventional equation of state $p=\\alpha\\rho$ is universal in the sector of small energy densities, and so is the resulting brane dynamics. The inequality $\\alpha<0$ is found to be a necessary condition for the existence of a stable ground state of the Universe. It is demonstrated that the generic braneworld physics rules out the Big Bang cosmology, and in that matter, any cosmology of finite lifetime. I also demonstrate that stable brane vibrations satisfy Klein-Gordon-like equation with an effective metric of Minkowski s...

  6. Bulk viscous cosmology in early Universe

    Indian Academy of Sciences (India)

    C P Singh

    2008-07-01

    The effect of bulk viscosity on the early evolution of Universe for a spatially homogeneous and isotropic Robertson-Walker model is considered. Einstein's field equations are solved by using `gamma-law' equation of state = ( - 1)ρ, where the adiabatic parameter gamma () depends on the scale factor of the model. The `gamma' function is defined in such a way that it describes a unified solution of early evolution of the Universe for inflationary and radiation-dominated phases. The fluid has only bulk viscous term and the coefficient of bulk viscosity is taken to be proportional to some power function of the energy density. The complete general solutions have been given through three cases. For flat space, power-law as well as exponential solutions are found. The problem of how the introduction of viscosity affects the appearance of singularity, is briefly discussed in particular solutions. The deceleration parameter has a freedom to vary with the scale factor of the model, which describes the accelerating expansion of the Universe.

  7. Bulk Higgs with a heavy diphoton signal

    Science.gov (United States)

    Frank, Mariana; Pourtolami, Nima; Toharia, Manuel

    2017-02-01

    We consider scenarios of warped extra dimensions with all matter fields in the bulk and in which both the hierarchy and the flavor puzzles of the Standard Model are addressed. Inspired by the puzzling excess of diphoton events at 750 GeV reported in the early LHC Run II data (since then understood as a statistical excess), we consider here the general question as to whether the simplest extra-dimensional extension of the Standard Model Higgs sector, i.e., a five-dimensional bulk Higgs doublet, can lead to an intermediate mass resonance (between 500 GeV and 1.5 TeV) of which the first signature would be the presence of diphoton events. This surprising phenomenology can happen if the resonance is the lightest C P -odd state coming from the Higgs sector. No new matter content is required, the only new ingredient being the presence of (positive) brane localized kinetic terms associated to the five-dimensional bulk Higgs (which reduce the mass of the C P -odd states). Production and decay of this resonance can naturally give rise to observable diphoton signals, keeping dijet production under control, with very low ZZ and WW signals and with a highly reduced top pair production in an important region of parameter space. We use the 750 GeV excess as an example case scenario.

  8. Cosmological Implications of QGP Bulk Viscosity

    CERN Document Server

    Anand, Sampurn; Bhatt, Jitesh R

    2016-01-01

    Recent studies of the hot QCD matter indicate that the bulk viscosity ($\\zeta$) of quark-gluon plasma (QGP) rises sharply near the critical point of the QCD phase transition. In this work, we show that such a sharp rise of the bulk viscosity will lead to an effective negative pressure near the critical temperature, $T_{c}$ which in turn drives the Universe to inflate. This inflation has a natural graceful exist when the viscous effect evanesce. We estimate that, depending upon the peak value of $\\zeta$, universe expands by a factor of $10$ to $80$ times in a very short span ($\\Delta t\\sim 10^{-8}$ seconds). Another important outcome of the bulk viscosity dominated dynamics is the cavitation of QGP around $T \\sim 1.5T_{c}$. This would lead to the phenomenon of formation of cavitation bubbles within the QGP phase. The above scenario is independent of the order of QCD phase transition. We delineate some of the important cosmological consequences of the inflation and the cavitation.

  9. Bulk Rashba Semiconductors and Related Quantum Phenomena.

    Science.gov (United States)

    Bahramy, Mohammad Saeed; Ogawa, Naoki

    2017-03-29

    Bithmuth tellurohalides BiTeX (X = Cl, Br and I) are model examples of bulk Rashba semiconductors, exhibiting a giant Rashba-type spin splitting among their both valence and conduction bands. Extensive spectroscopic and transport experiments combined with the state-of-the-art first-principles calculations have revealed many unique quantum phenomena emerging from the bulk Rashba effect in these systems. The novel features such as the exotic inter- and intra-band optical transitions, enhanced magneto-optical response, divergent orbital dia-/para-magnetic susceptibility and helical spin textures with a nontrivial Berry's phase in the momentum space are among the salient discoveries, all arising from this effect. Also, it is theoretically proposed and indications have been experimentally reported that bulk Rashba semiconductors such as BiTeI have the capability of becoming a topological insulator under the application of a hydrostatic pressure. Here, we overview these studies and show that BiTeX are an ideal platform to explore the next aspects of quantum matter, which could ultimately be utilized to create spintronic devices with novel functionalities.

  10. Molecular imprinting of bulk, microporous silica

    Science.gov (United States)

    Katz, Alexander; Davis, Mark E.

    2000-01-01

    Molecular imprinting aims to create solid materials containing chemical functionalities that are spatially organized by covalent or non-covalent interactions with imprint (or template) molecules during the synthesis process. Subsequent removal of the imprint molecules leaves behind designed sites for the recognition of small molecules, making the material ideally suited for applications such as separations, chemical sensing and catalysis. Until now, the molecular imprinting of bulk polymers and polymer and silica surfaces has been reported, but the extension of these methods to a wider range of materials remains problematic. For example, the formation of substrate-specific cavities within bulk silica, while conceptually straightforward, has been difficult to accomplish experimentally. Here we describe the imprinting of bulk amorphous silicas with single aromatic rings carrying up to three 3-aminopropyltriethoxysilane side groups; this generates and occupies microporosity and attaches functional organic groups to the pore walls in a controlled fashion. The triethoxysilane part of the molecules' side groups is incorporated into the silica framework during sol-gel synthesis, and subsequent removal of the aromatic core creates a cavity with spatially organized aminopropyl groups covalently anchored to the pore walls. We find that the imprinted silicas act as shape-selective base catalysts. Our strategy can be extended to imprint other functional groups, which should give access to a wide range of functionalized materials.

  11. Evidence for Bulk Ripplocations in Layered Solids

    Science.gov (United States)

    Gruber, Jacob; Lang, Andrew C.; Griggs, Justin; Taheri, Mitra L.; Tucker, Garritt J.; Barsoum, Michel W.

    2016-09-01

    Plastically anisotropic/layered solids are ubiquitous in nature and understanding how they deform is crucial in geology, nuclear engineering, microelectronics, among other fields. Recently, a new defect termed a ripplocation–best described as an atomic scale ripple–was proposed to explain deformation in two-dimensional solids. Herein, we leverage atomistic simulations of graphite to extend the ripplocation idea to bulk layered solids, and confirm that it is essentially a buckling phenomenon. In contrast to dislocations, bulk ripplocations have no Burgers vector and no polarity. In graphite, ripplocations are attracted to other ripplocations, both within the same, and on adjacent layers, the latter resulting in kink boundaries. Furthermore, we present transmission electron microscopy evidence consistent with the existence of bulk ripplocations in Ti3SiC2. Ripplocations are a topological imperative, as they allow atomic layers to glide relative to each other without breaking the in-plane bonds. A more complete understanding of their mechanics and behavior is critically important, and could profoundly influence our current understanding of how graphite, layered silicates, the MAX phases, and many other plastically anisotropic/layered solids, deform and accommodate strain.

  12. Temperature dependence of electron magnetic resonance spectra of iron oxide nanoparticles mineralized in Listeria innocua protein cages.

    Science.gov (United States)

    Usselman, Robert J; Russek, Stephen E; Klem, Michael T; Allen, Mark A; Douglas, Trevor; Young, Mark; Idzerda, Yves U; Singel, David J

    2012-10-15

    Electron magnetic resonance (EMR) spectroscopy was used to determine the magnetic properties of maghemite (γ-Fe(2)O(3)) nanoparticles formed within size-constraining Listeria innocua (LDps)-(DNA-binding protein from starved cells) protein cages that have an inner diameter of 5 nm. Variable-temperature X-band EMR spectra exhibited broad asymmetric resonances with a superimposed narrow peak at a gyromagnetic factor of g ≈ 2. The resonance structure, which depends on both superparamagnetic fluctuations and inhomogeneous broadening, changes dramatically as a function of temperature, and the overall linewidth becomes narrower with increasing temperature. Here, we compare two different models to simulate temperature-dependent lineshape trends. The temperature dependence for both models is derived from a Langevin behavior of the linewidth resulting from "anisotropy melting." The first uses either a truncated log-normal distribution of particle sizes or a bi-modal distribution and then a Landau-Liftshitz lineshape to describe the nanoparticle resonances. The essential feature of this model is that small particles have narrow linewidths and account for the g ≈ 2 feature with a constant resonance field, whereas larger particles have broad linewidths and undergo a shift in resonance field. The second model assumes uniform particles with a diameter around 4 nm and a random distribution of uniaxial anisotropy axes. This model uses a more precise calculation of the linewidth due to superparamagnetic fluctuations and a random distribution of anisotropies. Sharp features in the spectrum near g ≈ 2 are qualitatively predicted at high temperatures. Both models can account for many features of the observed spectra, although each has deficiencies. The first model leads to a nonphysical increase in magnetic moment as the temperature is increased if a log normal distribution of particles sizes is used. Introducing a bi-modal distribution of particle sizes resolves

  13. Temperature dependence of electron magnetic resonance spectra of iron oxide nanoparticles mineralized in Listeria innocua protein cages

    Science.gov (United States)

    Usselman, Robert J.; Russek, Stephen E.; Klem, Michael T.; Allen, Mark A.; Douglas, Trevor; Young, Mark; Idzerda, Yves U.; Singel, David J.

    2012-10-01

    Electron magnetic resonance (EMR) spectroscopy was used to determine the magnetic properties of maghemite (γ-Fe2O3) nanoparticles formed within size-constraining Listeria innocua (LDps)-(DNA-binding protein from starved cells) protein cages that have an inner diameter of 5 nm. Variable-temperature X-band EMR spectra exhibited broad asymmetric resonances with a superimposed narrow peak at a gyromagnetic factor of g ≈ 2. The resonance structure, which depends on both superparamagnetic fluctuations and inhomogeneous broadening, changes dramatically as a function of temperature, and the overall linewidth becomes narrower with increasing temperature. Here, we compare two different models to simulate temperature-dependent lineshape trends. The temperature dependence for both models is derived from a Langevin behavior of the linewidth resulting from "anisotropy melting." The first uses either a truncated log-normal distribution of particle sizes or a bi-modal distribution and then a Landau-Liftshitz lineshape to describe the nanoparticle resonances. The essential feature of this model is that small particles have narrow linewidths and account for the g ≈ 2 feature with a constant resonance field, whereas larger particles have broad linewidths and undergo a shift in resonance field. The second model assumes uniform particles with a diameter around 4 nm and a random distribution of uniaxial anisotropy axes. This model uses a more precise calculation of the linewidth due to superparamagnetic fluctuations and a random distribution of anisotropies. Sharp features in the spectrum near g ≈ 2 are qualitatively predicted at high temperatures. Both models can account for many features of the observed spectra, although each has deficiencies. The first model leads to a nonphysical increase in magnetic moment as the temperature is increased if a log normal distribution of particles sizes is used. Introducing a bi-modal distribution of particle sizes resolves the unphysical

  14. Urea-Functionalized M4L6 Cage Receptors: Self-Assembly, Dynamics, and Anion Recognition in Aqueous Solutions

    Energy Technology Data Exchange (ETDEWEB)

    Custelcean, Radu [ORNL; Bonnesen, Peter V [ORNL; Duncan, Nathan C [ORNL; Van Berkel, Gary J [ORNL; Hay, Benjamin [ORNL

    2012-01-01

    We present an extensive study of a novel class of de novo designed tetrahedral M{sub 4}L{sub 6} (M = Ni, Zn) cage receptors, wherein internal decoration of the cage cavities with urea anion-binding groups, via functionalization of the organic components L, led to selective encapsulation of tetrahedral oxoanions EO{sub 4}{sup -} (E = S, Se, Cr, Mo, W, n = 2; E = P, n = 3) from aqueous solutions, based on shape, size, and charge recognition. External functionalization with tBu groups led to enhanced solubility of the cages in aqueous methanol solutions, thereby allowing for their thorough characterization by multinuclear ({sup 1}H, {sup 13}C, {sup 77}Se) and diffusion NMR spectroscopies. Additional experimental characterization by electrospray ionization mass spectrometry, UV-vis spectroscopy, and single-crystal X-ray diffraction, as well as theoretical calculations, led to a detailed understanding of the cage structures, self-assembly, and anion encapsulation. We found that the cage self-assembly is templated by EO{sub 4}{sup -} oxoanions (n {ge} 2), and upon removal of the templating anion the tetrahedral M{sub 4}L{sub 6} cages rearrange into different coordination assemblies. The exchange selectivity among EO{sub 4}{sup -} oxoanions has been investigated with {sup 77}Se NMR spectroscopy using {sup 77}SeO{sub 4}{sup 2-} as an anionic probe, which found the following selectivity trend: PO{sub 4}{sup 3-} CrO{sub 4}{sup 2-} > SO{sub 4}{sup 2-} > SeO{sub 4}{sup 2-} > MoO{sub 4}{sup 2-} > WO{sub 4}{sup 2-}. In addition to the complementarity and flexibility of the cage receptor, a combination of factors have been found to contribute to the observed anion selectivity, including the anions charge, size, hydration, basicity, and hydrogen-bond acceptor abilities.

  15. Simultaneous Detection of Caga and Cage of Helicobacter pylori Strains Recovered from Iranian Patients with Different Gastroduodenal Diseases

    Directory of Open Access Journals (Sweden)

    M Douraghi

    2009-06-01

    Full Text Available "nBackground: To asses the status of two representative genes of cag PAI i.e cagA and cagE of Helicobacter pylori strains infecting Iranian patients suffered from various clinical outcomes using one-step PCR. "nMethods: A total of 120 H. pylori infected patients including non-ulcer dyspepsia, NUD (n=81, peptic ulcer disease, PUD (n=17, and gastric carcinoma, GC (n= 22 referred for endoscopy or gastric resection to AmirAlam Hospital or Cancer Institute from 2005 to 2008 were assessed. The status of cagA and cagE genes was determined by gene specific PCR."nResults: 84.2% and 90.8% of the tested strains were positive for cagA and cage, respectively. 81.7% strains were positive for both cagA and cagE genes, whereas 8 (6.7% were found double negative. The prevalence of cagA in GC patients (100% was slightly higher than PUD patients (94.1%. All of GC cases were infected with cagA-positive strains. The same distribution pattern was indicated for cagE gene in GC and PUD patients. The cagA-positive strains were significantly associated with GC as compared with NUD (P< 0.05 but this association did not gain statistical significance when cagE gene was assessed."nConclusion: The concurrent detection of cagA/cagE genes allowed rapid and specific clarification of cag PAI status. The strains with cagA/cagE genotype are predominant in Iran regardless of clinical outcome and create a distinct cluster pattern from those in the West and similar to those of East Asian countries. The current study also demonstrated that cagE gene can be explored as a better indication of cag-PAI in Iranian H. pylori strains.

  16. EFFECTS OF STRAIN, CAGE DENSITY AND POSITION ON IMMUNE RESPONSE TO VACCINES AND BLOOD PARAMETERS IN LAYER PULLETS

    Directory of Open Access Journals (Sweden)

    Z. BOZKURT

    2013-07-01

    Full Text Available Two thousand 1-day-old layer chicks were used in the study from Lohman Brown, Isa Brown, Lohman White and Bowans White breeds. The chicks were placed in the at 3 cage densities (211.8, 274.5 and 370.6 cm2 per bird and on 3 positions (as top, middle and bottom tiers. All birds were kept under standard management policy and a commercial vaccination program was practiced. Total specific antibody titres to Infectious Brochitis Virus (IBV, Infectious Bursal Desease Virus (IBDV, Newcastle Disease Virus (NDV and Egg Drop Syndrome Virus (EDSV vaccines at the ages of 5, 10 and 20 weeks were serologically determined by ELISA. Cellmediated immune response was also evaluated. In commercial white egg laying strains specific antibody titres to IBV, IBDV, NDV and EDSV vaccines were greater than in Brown egg layer strains. Keeping in cage created more stress in Brown egg laying chicks than those in white egg laying chicks. As cage density increased, the ratio of heterophils to lymphocytes (H/L ratio slightly increased. Cage position had no influence on the titres of antibodies to IBV and IBDV vaccines but the position of cage in pullets where chicks were stocked, from top to bottom, NDV and EDSV antibody titre decreased and percentage of heterophils, H/L ratio and basophil rates were low. These findings suggest that cage-related stress could be decreased, resistance to diseases and finally well-being of hens may be improved if hens are kept under proper position and density within cage systems with respect to their physiological and behavioral characteristics that controlled by genes.

  17. Evaluation of anterior cervical reconstruction with titanium mesh cages versus nano-hydroxyapatite/polyamide66 cages after 1- or 2-level corpectomy for multilevel cervical spondylotic myelopathy: a retrospective study of 117 patients.

    Directory of Open Access Journals (Sweden)

    Yuan Zhang

    Full Text Available OBJECTIVE: To retrospectively compare the efficacy of the titanium mesh cage (TMC and the nano-hydroxyapatite/polyamide66 cage (n-HA/PA66 cage for 1- or 2-level anterior cervical corpectomy and fusion (ACCF to treat multilevel cervical spondylotic myelopathy (MCSM. METHODS: A total of 117 consecutive patients with MCSM who underwent 1- or 2-level ACCF using a TMC or an n-HA/PA66 cage were studied retrospectively at a mean follow-up of 45.28 ± 12.83 months. The patients were divided into four groups according to the level of corpectomy (1- or 2-level corpectomy and cage type used (TMC or n-HA/PA66 cage. Clinical and radiological parameters were used to evaluate outcomes. RESULTS: At the one-year follow-up, the fusion rate in the n-HA/PA66 group was higher, albeit non-significantly, than that in the TMC group for both 1- and 2-level ACCF, but the fusion rates of the procedures were almost equal at the final follow-up. The incidence of cage subsidence at the final follow-up was significantly higher in the TMC group than in the n-HA/PA66 group for the 1-level ACCF (24% vs. 4%, p = 0.01, and the difference was greater for the 2-level ACCF between the TMC group and the n-HA/PA66 group (38% vs. 5%, p = 0.01. Meanwhile, a much greater loss of fused height was observed in the TMC group compared with the n-HA/PA66 group for both the 1- and 2-level ACCF. All four groups demonstrated increases in C2-C7 Cobb angle and JOA scores and decreases in VAS at the final follow-up compared with preoperative values. CONCLUSION: The lower incidence of cage subsidence, better maintenance of the height of the fused segment and similar excellent bony fusion indicate that the n-HA/PA66 cage may be a superior alternative to the TMC for cervical reconstruction after cervical corpectomy, in particular for 2-level ACCF.

  18. Tailoring Magnetic Properties in Bulk Nanostructured Solids

    Science.gov (United States)

    Morales, Jason Rolando

    Important magnetic properties and behaviors such as coercivity, remanence, susceptibility, energy product, and exchange coupling can be tailored by controlling the grain size, composition, and density of bulk magnetic materials. At nanometric length scales the grain size plays an increasingly important role since magnetic domain behavior and grain boundary concentration determine bulk magnetic behavior. This has spurred a significant amount of work devoted to developing magnetic materials with nanometric features (thickness, grain/crystallite size, inclusions or shells) in 0D (powder), 1D (wires), and 2D (thin films) materials. Large 3D nanocrystalline materials are more suitable for many applications such as permanent magnets, magneto-optical Faraday isolators etc. Yet there are relatively few successful demonstrations of 3D magnetic materials with nanoscale influenced properties available in the literature. Making dense 3D bulk materials with magnetic nanocrystalline microstructures is a challenge because many traditional densification techniques (HIP, pressureless sintering, etc.) move the microstructure out of the "nano" regime during densification. This dissertation shows that the Current Activated Pressure Assisted Densification (CAPAD) method, also known as spark plasma sintering, can be used to create dense, bulk, magnetic, nanocrystalline solids with varied compositions suited to fit many applications. The results of my research will first show important implications for the use of CAPAD for the production of exchange-coupled nanocomposite magnets. Decreases in grain size were shown to have a significant role in increasing the magnitude of exchange bias. Second, preferentially ordered bulk magnetic materials were produced with highly anisotropic material properties. The ordered microstructure resulted in changing magnetic property magnitudes (ex. change in coercivity by almost 10x) depending on the relative orientation (0° vs. 90°) of an externally

  19. AAH Cage Out-Link and In-Link Antenna Characterization

    Science.gov (United States)

    Jeutter, Dean C.

    1998-01-01

    This final report encapsulates the accomplishments of the third year of work on an Advanced Biotelemetry System (ABTS). Overall MU/ABTS project objectives are to provide a biotelemetry system that can collect data from and send commands to an implanted biotransceiver. This system will provide for studies of rodent development in space. The system must be capable of operating in a metal animal cage environment. An important goal is the development of a small, "smart", micropower, -channel data output and single channel command implantable biotransceiver with eight input capabilities with the flexibility for easy customization for a variety of physiologic investigations. The NASA Ames/Marquette University Joint Research work has been devoted to the system design of such a new state of the art biotelemetry system, having multiple physiologic inputs, and bi-directional data transfer capabilities. This work has provided a successful prototype system that connects, by two-way radio links, an addressable biotelemetry system that provides communication between an animal biotelemeter prototype and a personal computer. The operational features of the prototype system are listed below: Two-Way PCM Communication with Implanted Biotelemeter Microcontroller Based Biotelemeter Out-Link: Wideband FSK (60 kbaud) In-Link: OOK (2.4 kbaud) Septum Antenna Arrays (In/Out-Links) Personal Computer Data Interface The important requirement of this third year's work, to demonstrate two-way communication with transmit and receive antennas inside the metal animal cage, has been successfully accomplished. The advances discussed in this report demonstrate that the AAH cage antenna system can provide Out-link and In-link capability for the ABTS bi-directional telemetry system, and can serve as a benchmark for project status.

  20. Self-assembled hexanuclear organometallic cages: synthesis, characterization, and host-guest properties.

    Science.gov (United States)

    Han, Ying-Feng; Li, Hao; Zheng, Zhi-Fang; Jin, Guo-Xin

    2012-06-01

    A series of iridium- and rhodium-based hexanuclear organometallic cages containing 2,5-dichloro-3,6-dihydroxy-1,4-benzoquinone, 9,10-dihydroxy-1,4-anthraquinone, and 6,11-dihydroxynaphthacene-5,12-dione ligands were synthesized from the self-assembly of the corresponding molecular "clips" and 2,4,6-tri(4-pyridyl)-1,3,5-triazine ligands in good yields. These organometallic cages can form inclusion systems with a wide variety of π-donor substrates, including coronene, pyrene, [Pt(acac)(2)], and hexamethoxytriphenylene. The 1:1 complexation of the resulting supramolecular assemblies was confirmed by (1)H NMR spectroscopy. Large complexation shifts (Δδ>1 ppm) were observed in the (1)H NMR spectra of guests in the presence of cage [Cp*(6)M(6)(μ-DHNA)(3)(tpt)(2)](OTf)(6) (6a; M=Ir, tpt=2,4,6-tri(4-pyridyl)-1,3,5-triazine). The formation of discrete 1:1 donor-acceptor complexes, pyrene⊂6b (M=Rh), coronene⊂6a, coronene⊂6b, and [Pt(acac)(2)]⊂6a was confirmed by their single-crystal X-ray analyses. In these systems, the most important driving force for the formation of guest-host complexes is clearly the donor-acceptor π···π stacking interaction, including charge-transfer interactions between the electron-donating and electron-accepting aromatic components. These structures provide compelling evidence for the existence of strong attractive forces between the electron-deficient triazine core and electron-rich guest. The results presented here may provide useful guidance for designing artificial receptors for functional biomolecules.

  1. Cage-enrichment: rabbit does prefer straw or a compressed wooden block

    Directory of Open Access Journals (Sweden)

    Jorine M. Rommers

    2014-12-01

    Full Text Available The effect of different food related materials on the behaviour of commercial meat rabbit does was investigated to provide them enrichment. Five different treatments were tested. Control (pens without additional enrichment, C was compared with pens containing a pinewood stick (Pine, straw in a plastic bin (Straw, a compressed wooden block (Ply or a combination of straw and a pinewood stick (Straw+Pine. The experiment was conducted on a commercial rabbit farm using 80 cages with multiparous lactating hybrid (Hycole rabbit does. Behavioural observations were conducted in the first 4 wk of 2 successive lactations of 6 wk each, twice a week from 15:00 to 18:30 h. Once every week the consumption of gnawing materials and soiling of the cages was scored. More does were significantly occupied with Straw and Ply than with Pine (24±20, 11±9 and 4±3% of does, respectively for a longer duration (4±4, 2±2, 0.1±0.2% of observed time, respectively. In does of Straw+Pine group, the pinewood was barely touched and straw was preferred. It can be concluded that straw (loose material and wooden block are used by the animals as enrichment material to gnaw or chew on. The materials remain attractive for the 2 lactations which were measured. The pinewood stick as provided in this study was rarely used and it may be questioned whether it is sufficient as enrichment material or if it should be provided in another way than hanging on the roof of the cage. This study provides a first step towards a positive list of enrichment materials that can be used in commercial rabbit farming in The Netherlands.

  2. Early results of thoraco lumbar burst fracture treatment using selective corpectomy and rectangular cage reconstruction

    Science.gov (United States)

    Liang, Bowei; Huang, Guofeng; Ding, Luobing; Kang, Liangqi; Sha, Mo; Ding, Zhenqi

    2017-01-01

    Background: Subsidence and late fusion are commonly observed in anterior subtotal corpectomy and reconstruction for treating thoracolumbar burst fractures. The subsidence rate of this surgical method was reported from 19.6% to 75% in the literatures, which would cause treatment failure. Thus, an improvement of anterior surgery technique should be studied to reduce these complications. Materials and Methods: 130 patients of thoracolumbar burst fractures treated by minimal corpectomy, decompression and U cage, between January 2009 and December 2010 were included in this study. The hospital Ethical Committee approved the protocols. The American Spinal Injury Association (ASIA) scale, visual analog scales, and Oswestry Disability Index (ODI) scores were used for clinical evaluation. The local kyphosis angle, vertebral height (one level above the fractured vertebral to one level below), canal stenosis, and fusion status were used to assess radiological outcome. All complications and demographic data such as number of male/female patients, average age, mode of trauma, burst level involved, mean surgery time and blood lost were reported. Results: 120 patients were followed up for 24 months. Most patients had improvement of at least 1 ASIA grade, and all experienced pain reduction. The mean ODI score steadily decreased after the surgery (P 0.05). The average canal stenosis index was increased from 39% to 99% after surgery. No cage subsidence or implant failure was observed. Conclusions: The clinical outcomes described here suggest that the selective corpectomy and rectangular cage reconstruction can effectively promote solid fusion and eliminate complications related to subsidence or implant failure. PMID:28216750

  3. Photolysis of caged compounds: studying Ca(2+) signaling and activation of Ca(2+)-dependent ion channels.

    Science.gov (United States)

    Almassy, Janos; Yule, David I

    2013-01-01

    A wide variety of signaling molecules have been chemically modified by conjugation to a photolabile chromophore to render the substance temporarily biologically inert. Subsequent exposure to ultraviolet (UV) light can release the active moiety from the "caged" precursor in an experimentally controlled manner. This allows the concentration of active molecule to be precisely manipulated in both time and space. These techniques are particularly useful in experimental protocols designed to investigate the mechanisms underlying Ca(2+) signaling and the activation of Ca(2+)-dependent effectors.

  4. Biomonitoring of environmental pollution on the Algerian west coast using caged mussels Mytilus galloprovincialis

    Directory of Open Access Journals (Sweden)

    Jean-Claude Amiard

    2009-03-01

    Full Text Available An active biomonitoring study was carried out on the Algerian west coast using wild reference mussels (Mytilus galloprovincialis sampled from the Kristel (K site and transplanted in net cages during one month (between May and June 2007 to Oran Harbour (OH and Mostaganem Harbour (MH, areas characterised by high levels of urban and industrial pollution. The biological response of the mussels was evaluated by their condition index and the use of a general stress biomarker (evaluation of lysosomal membrane stability: the neutral red retention time (NRRT method, a genotoxic effects biomarker (determination of micronuclei (MN frequency and a neurotoxic effects biomarker (determination of the acetylcholinesterase (AChE concentration.       Compared to the K reference specimens, OH and MH caged mussels presented a significant decrease of NRRT in lysosomal haemocytes (56.45 ± 26.48 min and 67.25 ± 22.77 min, respectively (78 ± 16.97 min for K mussels, an MN frequency respectively 7.3 and 9 times higher in the haemocytes and the gill cells of the OH caged mussels, and 7.2 and 6.4 times higher in the two tissues of the MH caged mussels. Significant inhibition of AChE activity was noted in the gills (16.93 ± 3.1 nmol min-1 mg prot-1 and the digestive gland (7.69 ± 1.79 nmol min-1 mg prot-1 of the OH mussels, but only in the gills (23.21 ± 5.94 nmol min-1 mg prot-1 of the MH mussels, compared to the organs of the K control specimens (35.9 ± 6.4 nmol min-1 mg prot-1 in the gills and 11.17 ± 0.49 nmol min-1 mg prot-1 in the digestive gland.       This study reflects the interest in such in situ biomonitoring assays and the utility of these biomarkers for assessing the effects of pollution in the Algerian coastal marine environment.

  5. Standard practice for evaluating and qualifying oil field and refinery corrosion inhibitors using rotating cage

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2006-01-01

    1.1 This practice covers a generally accepted procedure to use the rotating cage (RC) for evaluating corrosion inhibitors for oil field and refinery applications. 1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  6. Narcissistic self-sorting in self-assembled cages of rare Earth metals and rigid ligands.

    Science.gov (United States)

    Johnson, Amber M; Wiley, Calvin A; Young, Michael C; Zhang, Xing; Lyon, Yana; Julian, Ryan R; Hooley, Richard J

    2015-05-04

    Highly selective, narcissistic self-sorting can be achieved in the formation of self-assembled cages of rare earth metals with multianionic salicylhydrazone ligands. The assembly process is highly sensitive to the length of the ligand and the coordination geometry. Most surprisingly, high-fidelity sorting is possible between ligands of identical coordination angle and geometry, differing only in a single functional group on the ligand core, which is not involved in the coordination. Supramolecular effects allow discrimination between pendant functions as similar as carbonyl or methylene groups in a complex assembly process.

  7. Diagnosis of Wind Energy System Faults Part I : Modeling of the Squirrel Cage Induction Generator

    Directory of Open Access Journals (Sweden)

    Lahcène Noureddine

    2015-08-01

    Full Text Available Generating electrical power from wind energy is becoming increasingly important throughout the world. This fast development has attracted many researchers and electrical engineers to work on this field. The authors develop a dynamic model of the squirrel cage induction generator exists usually on wind energy systems, for the diagnosis of broken rotor bars defects from an approach of magnetically coupled multiple circuits. The generalized model is established on the base of mathematical recurrences. The winding function theory is used for determining the rotor resistances and the inductances in the case of n- broken bars. Simulation results, in Part. II of this paper, confirm the validity of the proposed model.

  8. A chemist and biologist talk to each other about caged neurotransmitters

    Directory of Open Access Journals (Sweden)

    Graham C.R. Ellis-Davies

    2013-01-01

    Full Text Available Caged compounds are small organic molecules that can be photoactivated with brief pulses of light. They are widely used to study a great variety of biological processes by physiologists, cell biologists and neuroscientists. Initially made and invented by biologists in the late 1970s, they are now made mostly by chemists, often without any dialogue with the end users, the biologists. The idea for this review is to stimulate interaction between the two communities to further the creative development and application of these powerful optical probes.

  9. First-principles study of hydrogen storage on Li12F12 nano-cage

    Science.gov (United States)

    Zhang, Yafei; Cheng, Xinlu

    2017-03-01

    We use the first-principles calculation based on density functional theory (DFT) to investigate the hydrogen storage on Li12F12 nano-cage. Our result indicates the largest hydrogen gravimetric density is 7.14 wt% and this is higher than the 2017 target from the US department of energy (DOE). Meanwhile, the average adsorption energy is -0.161 eV/H2, which is desirable for absorbing and desorbing H2 molecules at near ambient conditions. These findings will have important implications on designing hydrogen storage materials in the future.

  10. A direct comparison of protein structure in the gas and solution phase: the Trp-cage

    DEFF Research Database (Denmark)

    Patriksson, Alexandra; Adams, Christopher M; Kjeldsen, Frank;

    2007-01-01

    Molecular dynamics simulations of zwitterions of the Trp-cage protein in the gas phase show that the most stable ion in vacuo has preserved the charge locations acquired in solution. A direct comparison of the gas and solution-phase structures reveals that, despite the similarity in charge location......, there is significant difference in the structures, with a substantial increase in hydrogen bonds and exposure of hydrophobic parts in the gas phase. The structure of the salt bridge in the gas phase is also much more stable than in the (experimental) solution structure....

  11. Theoretical prediction of novel ultrafine nanowires formed by Si12C12 cage-like clusters

    Science.gov (United States)

    Yong, Yongliang; Song, Bin; He, Pimo

    2014-02-01

    Using density functional theory calculations, we predict that novel SiC ultrafine nanowires can be produced via the coalescence of stable Si12C12 clusters. For the isolated Si12C12 clusters, we find that the cage-like structure with a distinct segregation between Si and C atoms is energetically more favourable than the fullerene-like structure with alternating Si-C bonds. Via the coalescence of Si12C12 clusters, three novel stable nanowires have been characterised. The band structure reveals that these nanowires are semiconductors with narrow gap, indicating that they may be used as infrared detectors and thermoelectrics.

  12. Catalytic Metal Free Production of Large Cage Structure Carbon Particles: A Candidate for Hydrogen Storage

    Science.gov (United States)

    Kimura, Yuki; Nuth, Joseph A., III; Ferguson, Frank T.

    2005-01-01

    We will demonstrate that carbon particles consisting of large cages can be produced without catalytic metal. The carbon particles were produced in CO gas as well as by introduction of 5% methane gas into the CO gas. The gas-produced carbon particles were able to absorb approximately 16.2 wt% of hydrogen. This value is 2.5 times higher than the 6.5 wt% goal for the vehicular hydrogen storage proposed by the Department of Energy in the USA. Therefore, we believe that this carbon particle is an excellent candidate for hydrogen storage for fuel cells.

  13. Life Cycle Assessment of Farmed Salmon, Comparing a Closed with an Open Sea Cage System

    OpenAIRE

    2014-01-01

    Ole Jonny Nyhus, Marine Technology, Norwegian University of Science and Technology.Abstract of Master's Thesis, levert 8. juni, 2014:Life Cycle Assessment of Farmed Salmon, Comparing a Closed with an Open Sea Cage System.The goal of this Master's Thesis is to do a Life Cycle Assessment (LCA) on a closed fish farm system and compare it to an open fish farm system, for so to make recommendations based on the results.Life Cycle Assessment is a method to calculate the environmental impa...

  14. Separation of rare gases and chiral molecules by selective binding in porous organic cages

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Linjiang; Reiss, Paul S.; Chong, Samantha Y.; Holden, Daniel; Jelfs, Kim E.; Hasell, Tom; Little, Marc A.; Kewley, Adam; Briggs, Michael E.; Stephenson, Andrew; Thomas, K. M.; Armstrong, Jayne A.; Bell, Jon; Busto, Jose; Noel, Raymond; Liu, Jian; Strachan, Denis M.; Thallapally, Praveen K.; Cooper, Andrew I.

    2014-10-31

    Abstract: The rare gases krypton, xenon, and radon pose both an economic opportunity and a potential environmental hazard. Xenon is used in commercial lighting, medical imaging, and anesthesia, and can sell for $5,000 per kilogram. Radon, by contrast, Is naturally radioactive and the second largest cause of lung cancer, and radioactive xenon, 133Xe, was a major pollutant released In the Fukushima Daiichi Nuclear Power Plant disaster. We describe an organic cage molecule that can capture xenon and radon with unprecedented selectivity, suggesting new technologies for environmental monitoring, removal of pollutants, or the recovery of rare, valuable elements from air.

  15. Cage-enrichment: rabbit does prefer straw or a compressed wooden block

    OpenAIRE

    Rommers, Jorine M.; Bracke, Marc B.M.; Berry Reuvekamp; Henk Gunnink; Ingrid C. de Jong

    2014-01-01

    The effect of different food related materials on the behaviour of commercial meat rabbit does was investigated to provide them enrichment. Five different treatments were tested. Control (pens without additional enrichment, C) was compared with pens containing a pinewood stick (Pine), straw in a plastic bin (Straw), a compressed wooden block (Ply) or a combination of straw and a pinewood stick (Straw+Pine). The experiment was conducted on a commercial rabbit farm using 80 cages with multiparo...

  16. Myxozoan pathogens of Malaysian fishes cultured in ponds and net-cages.

    Science.gov (United States)

    Székely, Cs; Shaharom-Harrison, F; Cech, G; Mohamed, K; Molnár, K

    2009-01-28

    We describe new myxosporean species from Malaysian fishes cultured in pond farms and net-cages. Myxobolus omari sp. nov. and M. leptobarbi sp. nov. were found in the muscles of Pangasianodon hypophthalmus and Leptobarbus hoevenii, respectively, while plasmodia and spores of Thelohanellus zahrahae sp. nov. and Henneguya daoudi sp. nov. were detected in the gills of Barbonymus gonionotus and Trichogaster trichopterus, respectively. Plasmodia and spores found in these fishes differed from the known myxosporean species in respect of their morphology, tissue tropism and 18S rDNA structure. No major pathological changes were found, but in the future these species might pose a potential threat to more intensified fish culture.

  17. Assembly and structural analysis of a covalently closed nano-scale DNA cage

    DEFF Research Database (Denmark)

    Andersen, Felicie F; Knudsen, Bjarne; Oliveira, Cristiano Luis Pinto De

    2008-01-01

     The inherent properties of DNA as a stable polymer with unique affinity for partner molecules determined by the specific Watson-Crick base pairing makes it an ideal component in self-assembling structures. This has been exploited for decades in the design of a variety of artificial substrates...... be described as a nano-scale DNA cage, Hence, in theory it could hold proteins or other bio-molecules to enable their investigation in certain harmful environments or even allow their organization into higher order structures...

  18. Enzyme Treatment-Free and Ligation-Independent Cloning Using Caged Primers in Polymerase Chain Reactions

    Directory of Open Access Journals (Sweden)

    Akinori Kuzuya

    2011-12-01

    Full Text Available A new simple scheme for constructing recombinant vectors that does not require any restriction enzyme, ligase, or any other special enzyme treatment has been developed. By using caged primers in PCR, unnatural sticky-ends of any sequence, which are sufficiently long for ligation-independent cloning (LIC, are directly prepared on the product after a brief UVA irradiation. Target genes and vectors amplified by this light-assisted cohesive-ending (LACE PCR join together in the desired arrangement in a simple mixture of them, tightly enough to be repaired and ligated in competent cells.

  19. Current signature analysis for condition monitoring of cage induction motors industrial application and case histories

    CERN Document Server

    Thomson, William T

    2017-01-01

    This book has 13 chapters and contains a unique database of 50 industrial case histories on theapplication of MCSA to diagnose broken rotor bars or unacceptable levels of airgap eccentricity in cage induction motors with ratings from 127 kW (170 H.P.) to 10,160 kW (13,620 H.P.). There are also unsuccessful case histories which is another unique feature of the book. The case studies also illustrate the effects of mechanical load dynamics downstream of the motor on the interpretation of current signatures. A number of cases are presented where abnormal operation of the driven loadwas diagnosed.

  20. Mycobacteriosis in wild rabbitfish Siganus rivulatus associated with cage farming in the Gulf of Eilat, Red Sea.

    Science.gov (United States)

    Diamant, A; Banet, A; Ucko, M; Colorni, A; Knibb, W; Kvitt, H

    2000-02-01

    Infection patterns of Mycobacterium marinum were studied over a period of 3 yr in wild rabbitfish Siganus nivulatus populations associated with commercial mariculture cages and inhabiting various sites along the Israeli Red Sea coastline. Mycobacteriosis was first recorded from the Red Sea in 1990 in farmed sea bass Dicentrarchus labrax and is absent from records of studies on parasites and diseases of wild rabbitfish carried out in the 1970s and 1980s. A sharp increase in the prevalence of the disease in cultured and wild fish in the region has occurred since. A total of 1142 rabbitfish were examined over a 3 yr period from inside mariculture net cages, from the cage surroundings and from several sites along the coast. Histological sections of spleens were examined for presence of granulomatous lesions. Overall prevalence levels of 50% were recorded in the rabbitfish sampled inside the net cages and 39% at the cages' close surroundings, 21% at a sandy beach site 1.2 km westwards, 35% at Eilat harbour 3 km to the south and 42% at a coral reef site about 10 km south of the cages. In addition, 147 fish belonging to 18 native Red Sea species were sampled from 2 sites, the net cage farm perimeter and the coral reef area, and examined for similar lesions. None of those from the coral reef were infected with Mycobacterium; however, 9 of 14 species collected from the cage surroundings were infected. An increase in prevalence of mycobacteriosis in the mariculture farm area was noted from 1995 to 1997. At the same time, a significant increase in prevalence was also apparent at the coral reef sampling site. Two M. marinum isolates from rabbitfish captured at Eilat harbour and the coral reef site were shown by 16S rDNA sequencing analysis to be identical to isolates from rabbitfish trapped inside the mariculture cages as well as isolates from locally cultured sea bass D. labrax. The implications of spreading of M. marinum infection in wild fish populations in the Gulf of

  1. Unique properties of C,C'-linked nido-biscarborane tetraanions. Synthesis, structure and bonding of ruthenium monocarbollide via unprecedented cage carbon extrusion.

    Science.gov (United States)

    Zhao, Da; Zhang, Jiji; Lin, Zhenyang; Xie, Zuowei

    2016-08-21

    Four reaction pathways have been found in the reaction of a C,C'-linked nido-biscarborane tetraanionic salt with [Ru(p-cymene)Cl2]2, leading to the isolation and structural characterization of redox, triple cage B-H oxidative addition, cage expansion and cage carbon extrusion products. Among these, the unprecedented cage carbon extrusion results in the formation of a new 6π-electron carboranyl ligand [C2B10H10](2-). The bonding interactions between this ligand and the Ru(ii) center have also been discussed on the basis of DFT calculations.

  2. The theory of an arbitrarily perturbed bird-cage resonator, and a simple method for restoring it to full symmetry

    Science.gov (United States)

    Tropp, James

    The first-order theory of a low-pass bird-cage resonator perturbed at a single capacitor [J. Tropp, J. Magn. Reson.82, 51 (1989)] is extended by explicit calculation to cover a low-pass bird cage perturbed arbitrarily at every reactance, provided that a first-order condition is satisfied. It is shown that the effect of arbitrary perturbation, i.e., the splitting of resonances and rotation of the polarization axes, can be exactly mimicked (in first order) by a pair of capacitors spaced by an azimuth of {π}/{4}. This result may be extended by symmetry arguments to the high-pass and simple band-pass bird cage. A method of correcting symmetry (abolishing the splitting of the useful eigenstates) is then derived, which provides near-perfect correction by the application of two capacitors, typically spaced {π}/{4} on the resonator azimuth. Experimental results are given for a low-pass bird-cage; and the correction procedure is verified and demonstrated in practical detail; and it is shown that the limit of the first-order theory is that the first of the two requisite correction capacitors should be within 7 or 8% of the nominal bird-cage capacitance. Practical examples of symmetry correction outside the first-order regime are also given.

  3. Why can water cages adsorb aqueous methane? A potential of mean force calculation on hydrate nucleation mechanisms.

    Science.gov (United States)

    Guo, Guang-Jun; Li, Meng; Zhang, Yi-Gang; Wu, Chang-Hua

    2009-11-28

    By performing constrained molecular dynamics simulations in the methane-water system, we successfully calculated the potential of mean force (PMF) between a dodecahedral water cage (DWC) and dissolved methane for the first time. As a function of the distance between DWC and methane, this is characterized by a deep well at approximately 6.2 A and a shallow well at approximately 10.2 A, separated by a potential barrier at approximately 8.8 A. We investigated how the guest molecule, cage rigidity and the cage orientation affected the PMF. The most important finding is that the DWC itself strongly adsorbs methane and the adsorption interaction is independent of the guests. Moreover, the activation energy of the DWC adsorbing methane is comparable to that of hydrogen bonds, despite differing by a factor of approximately 10% when considering different water-methane interaction potentials. We explain that the cage-methane adsorption interaction is a special case of the hydrophobic interaction between methane molecules. The strong net attraction in the DWC shell with radii between 6.2 and 8.8 A may act as the inherent driving force that controls hydrate formation. A cage adsorption hypothesis for hydrate nucleation is thus proposed and discussed.

  4. Contamination of eggs by Salmonella Enteritidis in experimentally infected laying hens housed in conventional or enriched cages.

    Science.gov (United States)

    Gast, Richard K; Guraya, Rupa; Jones, Deana R; Anderson, Kenneth E

    2014-03-01

    Both epidemiologic analyses and active disease surveillance confirm an ongoing strong association between human salmonellosis and the prevalence of Salmonella enterica subspecies enterica serovar Enteritidis in commercial egg flocks. The majority of human illnesses caused by this pathogen are attributed to the consumption of contaminated eggs. Animal welfare concerns have increasingly influenced commercial poultry production practices in recent years, but the food safety implications of different housing systems for egg-laying hens are not definitively understood. The present study assessed the effects of 2 different housing systems (conventional cages and colony cages enriched with perching and nesting areas) on the frequency of Salmonella Enteritidis contamination inside eggs laid by experimentally infected laying hens. In each of 2 trials, groups of laying hens housed in each cage system were orally inoculated with doses of 1.0 × 10(8) cfu of Salmonella Enteritidis. All eggs laid between 5 and 25 d postinoculation were collected and cultured to detect internal contamination with Salmonella Enteritidis. For both trials combined, Salmonella Enteritidis was recovered from 3.97% of eggs laid by hens in conventional cages and 3.58% of eggs laid by hens in enriched cages. No significant differences (P > 0.05) in the frequency of egg contamination were observed between the 2 housing systems.

  5. A statistical human rib cage geometry model accounting for variations by age, sex, stature and body mass index.

    Science.gov (United States)

    Shi, Xiangnan; Cao, Libo; Reed, Matthew P; Rupp, Jonathan D; Hoff, Carrie N; Hu, Jingwen

    2014-07-18

    In this study, we developed a statistical rib cage geometry model accounting for variations by age, sex, stature and body mass index (BMI). Thorax CT scans were obtained from 89 subjects approximately evenly distributed among 8 age groups and both sexes. Threshold-based CT image segmentation was performed to extract the rib geometries, and a total of 464 landmarks on the left side of each subject׳s ribcage were collected to describe the size and shape of the rib cage as well as the cross-sectional geometry of each rib. Principal component analysis and multivariate regression analysis were conducted to predict rib cage geometry as a function of age, sex, stature, and BMI, all of which showed strong effects on rib cage geometry. Except for BMI, all parameters also showed significant effects on rib cross-sectional area using a linear mixed model. This statistical rib cage geometry model can serve as a geometric basis for developing a parametric human thorax finite element model for quantifying effects from different human attributes on thoracic injury risks.

  6. Structural and mechanical evaluations of a topology optimized titanium interbody fusion cage fabricated by selective laser melting process.

    Science.gov (United States)

    Lin, Chia-Ying; Wirtz, Tobias; LaMarca, Frank; Hollister, Scott J

    2007-11-01

    A topology optimized lumbar interbody fusion cage was made of Ti-Al6-V4 alloy by the rapid prototyping process of selective laser melting (SLM) to reproduce designed microstructure features. Radiographic characterizations and the mechanical properties were investigated to determine how the structural characteristics of the fabricated cage were reproduced from design characteristics using micro-computed tomography scanning. The mechanical modulus of the designed cage was also measured to compare with tantalum, a widely used porous metal. The designed microstructures can be clearly seen in the micrographs of the micro-CT and scanning electron microscopy examinations, showing the SLM process can reproduce intricate microscopic features from the original designs. No imaging artifacts from micro-CT were found. The average compressive modulus of the tested caged was 2.97+/-0.90 GPa, which is comparable with the reported porous tantalum modulus of 3 GPa and falls between that of cortical bone (15 GPa) and trabecular bone (0.1-0.5 GPa). The new porous Ti-6Al-4V optimal-structure cage fabricated by SLM process gave consistent mechanical properties without artifactual distortion in the imaging modalities and thus it can be a promising alternative as a porous implant for spine fusion.

  7. Optopharmacological control of TRPC channels by coumarin-caged lipids is associated with a phototoxic membrane effect.

    Science.gov (United States)

    Tiapko, Oleksandra; Bacsa, Bernadett; de la Cruz, Gema Guedes; Glasnov, Toma; Groschner, Klaus

    2016-08-01

    Photouncaging of second messengers has been successfully employed to gain mechanistic insight of cellular signaling pathways. One of the most enigmatic processes of ion channel regulation is lipid recognition and lipid-gating of TRPC channels, which represents pivotal mechanisms of cellular Ca(2+) homeostasis. Recently, optopharmacological tools including caged lipid mediators became available, enabling an unprecedented level of temporal and spatial control of the activating lipid species within a cellular environment. Here we tested a commonly used caged ligand approach for suitability to investigate TRPC signaling at the level of membrane conductance and cellular Ca(2+) handling. We report a specific photouncaging artifact that is triggered by the cage structure coumarin at UV illumination. Electrophysiological characterization identified a light-dependent membrane effect of coumarin. UV light (340 nm) as used for photouncaging, initiated a membrane conductance specifically in the presence of coumarin as low as 30 μmol L(-1) concentrations. This conductance masked the TRPC3 conductance evoked by photouncaging, while TRPC-mediated cellular Ca(2+) responses were largely preserved. The observed light-induced membrane effects of the released caging moiety may well interfere with certain cellular functions, and prompt caution in using coumarin-caged second messengers in cellular studies.

  8. Symmetric caging formation for convex polygonal object transportation by multiple mobile robots based on fuzzy sliding mode control.

    Science.gov (United States)

    Dai, Yanyan; Kim, YoonGu; Wee, SungGil; Lee, DongHa; Lee, SukGyu

    2016-01-01

    In this paper, the problem of object caging and transporting is considered for multiple mobile robots. With the consideration of minimizing the number of robots and decreasing the rotation of the object, the proper points are calculated and assigned to the multiple mobile robots to allow them to form a symmetric caging formation. The caging formation guarantees that all of the Euclidean distances between any two adjacent robots are smaller than the minimal width of the polygonal object so that the object cannot escape. In order to avoid collision among robots, the parameter of the robots radius is utilized to design the caging formation, and the A⁎ algorithm is used so that mobile robots can move to the proper points. In order to avoid obstacles, the robots and the object are regarded as a rigid body to apply artificial potential field method. The fuzzy sliding mode control method is applied for tracking control of the nonholonomic mobile robots. Finally, the simulation and experimental results show that multiple mobile robots are able to cage and transport the polygonal object to the goal position, avoiding obstacles.

  9. Faraday cage-type electrochemiluminescence immunosensor for ultrasensitive detection of Vibrio vulnificus based on multi-functionalized graphene oxide.

    Science.gov (United States)

    Guo, Zhiyong; Sha, Yuhong; Hu, Yufang; Yu, Zhongqing; Tao, Yingying; Wu, Yanjie; Zeng, Min; Wang, Sui; Li, Xing; Zhou, Jun; Su, Xiurong

    2016-10-01

    A novel Faraday cage-type electrochemiluminescence (ECL) immunosensor devoted to the detection of Vibrio vulnificus (VV) was fabricated. The sensing strategy was presented by a unique Faraday cage-type immunocomplex based on immunomagnetic beads (IMBs) and multi-functionalized graphene oxide (GO) labeled with (2,2'-bipyridine)(5-aminophenanthroline)ruthenium (Ru-NH2). The multi-functionalized GO could sit on the electrode surface directly due to the large surface area, abundant functional groups, and good electronic transport property. It ensures that more Ru-NH2 is entirely caged and become "effective," thus improving sensitivity significantly, which resembles extending the outer Helmholtz plane (OHP) of the electrode. Under optimal conditions, the developed immunosensor achieves a limit of detection as low as 1 CFU/mL. Additionally, the proposed immunosensor with high sensitivity and selectivity can be used for the detection of real samples. The novel Faraday cage-type method has shown potential application for the diagnosis of VV and opens up a new avenue in ECL immunoassay. Graphical abstract Faraday cage-type immunoassay mode for ultrasensitive detection by extending OHP.

  10. Materials for Bulk Acoustic Resonators and Filters

    Science.gov (United States)

    Loebl, Hans-Peter

    2003-03-01

    Highly selective solidly mounted bulk acoustic wave (BAW) band pass filters are suited for mobile and wireless systems in the GHz frequency range between 0.8 and 10 GHz. Electro-acoustic thin film BAW resonators are the building blocks these BAW filters. Piezoelectric materials used in these resonators include mainly AlN or ZnO which can be deposited by dedicated thin film sputter deposition techniques. Using these piezo-electric materials and using suited materials for the acoustic Bragg reflector, BAW resonators with high quality factors can be fabricated. The achievable filter bandwidth is approximately 4Alternatively, also ferroelectric thin films might be used to achieve higher coupling coefficient and thus filter bandwidth. BAW resonators and filters have been designed and fabricated on 6" Silicon and glass wafers. Results are presented for resonators and filters operating between 1.95 and 8 GHz. The talk will give an overview of the material aspects which are important for BAW devices. It will be shown that modeling of the resonator and filter response using 1D electro-acoustic simulation (1,2) which includes losses is essential to extract acoustic and electrical material parameters. (1) Solidly Mounted Bulk Acoustic Wave Filters for the Ghz Frequency Range, H.P. Loebl, C. Metzmacher , D.N.Peligrad , R. Mauczok , M. Klee , W. Brand , R.F. Milsom , P.Lok , F.van Straten , A. Tuinhout , J.W.Lobeek, IEEE 2002 Ultrasonics Symposium Munich, October 2002. (2) Combined Acoustic-Electromagnetic Simulation Of Thin-Film Bulk Acoustic Wave Filters, R.F. Milsom, H-P. Löbl, D.N. Peligrad, J-W. Lobeek, A. Tuinhout, R. H. ten Dolle IEEE 2002 Ultrasonics Symposium Munich, October 2002.

  11. Improving the bulk data transfer experience

    Energy Technology Data Exchange (ETDEWEB)

    Guok, Chin; Guok, Chin; Lee, Jason R.; Berket, Karlo

    2008-05-07

    Scientific computations and collaborations increasingly rely on the network to provide high-speed data transfer, dissemination of results, access to instruments, support for computational steering, etc. The Energy Sciences Network is establishing a science data network to provide user driven bandwidth allocation. In a shared network environment, some reservations may not be granted due to the lack of available bandwidth on any single path. In many cases, the available bandwidth across multiple paths would be sufficient to grant the reservation. In this paper we investigate how to utilize the available bandwidth across multiple paths in the case of bulk data transfer.

  12. Binary Cu-Zr Bulk Metallic Glasses

    Institute of Scientific and Technical Information of China (English)

    TANG Mei-Bo; ZHAO De-Qian; PAN Ming-Xiang; WANG Wei-Hua

    2004-01-01

    @@ We report that bulk metallic glasses (BMGs) can be produced up to 2 mm by a copper mould casting in Cux Zr1-x binary alloy with a wide glass forming composition range (45 < x < 60 at.%). We find that the formation mechanism for the binary Cu-Zr binary BMG-forming alloy is obviously different from that of the intensively studied multicomponent BMGs. Our results demonstrate that the criteria for the multicomponent alloys with composition near deep eutectic and strong liquid behaviour are no longer the major concern for designing BMGs.

  13. Calculated Bulk Properties of the Actinide Metals

    DEFF Research Database (Denmark)

    Skriver, Hans Lomholt; Andersen, O. K.; Johansson, B.

    1978-01-01

    Self-consistent relativistic calculations of the electronic properties for seven actinides (Ac-Am) have been performed using the linear muffin-tin orbitals method within the atomic-sphere approximation. Exchange and correlation were included in the local spin-density scheme. The theory explains...... the variation of the atomic volume and the bulk modulus through the 5f series in terms of an increasing 5f binding up to plutonium followed by a sudden localisation (through complete spin polarisation) in americium...

  14. Diffusion and bulk flow in phloem loading

    DEFF Research Database (Denmark)

    Dölger, Julia; Rademaker, Hanna; Liesche, Johannes

    2014-01-01

    loading mechanism, active symplasmic loading, also called the polymer trap mechanism, where sucrose is transformed into heavier sugars, such as raffinose and stachyose, in the intermediary-type companion cells bordering the sieve elements in the minor veins of the phloem. Keeping the heavier sugars from......%-20% to the sucrose flux into the intermediary cells, while the main part is transported by diffusion. On the other hand, the subsequent sugar translocation into the sieve elements would very likely be carried predominantly by bulk water flow through the plasmodesmata. Thus, in contrast to apoplasmic loaders, all...

  15. Fabrication of Porous Bulk Metallic Glass

    Institute of Scientific and Technical Information of China (English)

    Keqiang QIU; Yinglei REN

    2005-01-01

    An open-cell porous bulk metallic glass (BMG)with a diameter of at least 6 mm was fabricated by using an U-turn quartz tube and infiltration casting aroundsoluble NaCl placeholders. The pore formation and glassy structure were examined by optical microscopy (OM), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results show that the pores or cells are connected to each other and the specimenis composed of a mostly glassy phase.This paper provides a suitable method for fabrication of porous BMG and BMG with larger size in diameter.

  16. Hubble Parameter in Bulk Viscous Cosmology

    CERN Document Server

    Tawfik, A; Wahba, M

    2009-01-01

    We discuss influences of bulk viscosity on the Early Universe, which is modeled by Friedmann-Robertson-Walker metric and Einstein field equations. We assume that the matter filling the isotropic and homogeneous background is relativistic viscous characterized by ultra-relativistic equations of state deduced from recent lattice QCD simulations. We obtain a set of complicated differential equations, for which we suggest approximate solutions for Hubble parameter $H$. We find that finite viscosity in Eckart and Israel-Stewart fluids would significantly modify our picture about the Early Universe.

  17. Production, Properties and Applications of Bulk Amorphous Alloys

    Institute of Scientific and Technical Information of China (English)

    Tao Zhang; Akihisa Inoue

    2000-01-01

    A review is given of recent work concerned with the production method, the characteristic properties(1) Bulk amorphous system; (2) Mechanical and magnetic properties of bulkamorphous alloys; (3)application of bulk amorphous alloys.

  18. Integrated coastal monitoring of a gas processing plant using native and caged mussels

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, Steven, E-mail: sbr@niva.no [Norwegian Institute for Water Research (NIVA), Gaustadalleen 21, NO-0349 Oslo (Norway); Harman, Christopher [Norwegian Institute for Water Research (NIVA), Gaustadalleen 21, NO-0349 Oslo (Norway); Soto, Manu; Cancio, Ibon [CBET Res Grp, R and D Centre for Experimental Marine Biology and Biotechnology (PIE), Univ Basque Country, Areatza Z/G, Plentzia-Bizkaia, E-48620 Basque Country (Spain); Glette, Tormod [Det Norske Veritas (DNV), Veritasveien 1, 1363 Hovik (Norway); Marigomez, Ionan [CBET Res Grp, R and D Centre for Experimental Marine Biology and Biotechnology (PIE), Univ Basque Country, Areatza Z/G, Plentzia-Bizkaia, E-48620 Basque Country (Spain)

    2012-06-01

    The biological effects of a coastal process water (PW) discharge on native and caged mussels (Mytilus edulis) were assessed. Chemical analyses of mussel tissues and semi permeable membrane devices, along with a suite of biomarkers of different levels of biological complexity were measured. These were lysosomal membrane stability in haemocytes and digestive cells; micronuclei formation in haemocytes; changes in cell-type composition in the digestive gland epithelium; integrity of digestive gland tissue; peroxisome proliferation; and oxidative stress. Additionally the Integrative Biological Response (IBR/n) index was calculated. This integrative biomarker approach distinguished mussels, both native and caged, exhibiting different stress conditions not identified from the contaminant exposure. Mussels exhibiting higher stress responses were found with increased proximity to the PW discharge outlet. However, the biological effects reported could not be entirely attributed to the PW discharge based on the chemicals measured, but were likely due to either other chemicals in the discharge that were not measured, the general impact of the processing plant and or other activities in the local vicinity. - Highlights: Black-Right-Pointing-Pointer Good agreement between biomarkers for the different mussel groups. Black-Right-Pointing-Pointer IBR/n was able to differentiate between exposed and reference mussels. Black-Right-Pointing-Pointer Mussels closest to the PW outlet were in poorest health. Black-Right-Pointing-Pointer Chemical concentrations were low or undetected in all SPMD and mussel samples. Black-Right-Pointing-Pointer Biomarker responses could not be entirely attributed to the PW discharge.

  19. Novel caged clusters of silicon: Fullerenes, Frank–Kasper polyhedron and cubic

    Indian Academy of Sciences (India)

    Vijay Kumar

    2003-01-01

    We review recent findings of metal (M) encapsulated caged clusters of Si and Ge obtained from computer experiments based on an ab initio pseudopotential method. It is shown that one M atom changes drastically the properties of Si and Ge clusters and that depending upon the size of the M atom, cages of 14, 15, and 16 Si as well as Ge atoms are formed. In particular M@Si16 silicon fullerene has been obtained for M = Zr and Hf, while a Frank–Kasper polyhedron has been obtained for M@X16, X = Si and Ge. These clusters show high stability and large highest occupied–lowest unoccupied molecular orbital (HOMO–LUMO) gaps which are likely to make these species strongly abundant. A regular icosahedral M@X12 cluster has also been obtained for X = Ge and Sn by doping a divalent M atom. Interactions between clusters are rather weak. This is attractive for developing self-assembled cluster materials.

  20. The development of stereotypic behavior in caged European starlings, Sturnus vulgaris.

    Science.gov (United States)

    Feenders, Gesa; Bateson, Melissa

    2012-12-01

    Stereotypic behavior in captive animals has been hypothesized to emerge from thwarted natural behavior patterns and is thought to be more common in captive-reared animals. However, data on the early stages of developing stereotypies are currently scarce. We compared the development of stereotypic route-tracing and somersaulting in hand-reared and wild-caught starlings placed in individual cages for the first time. We found that wild-caught birds were less active but showed more escape motivation and more evidence of route-tracing behavior. Furthermore, somersaulting was only observed in wild-caught birds. Development of somersaulting was predicted by subtle differences in behavior during the first few days in cages and developed in individuals with low levels of route-tracing behavior. Our data suggest a role for escape motivation in the development of starling stereotypies and additionally that route-tracing and somersaulting may represent alternative outlets for thwarted escape. In contrast to observations from mammals, our results show that stereotypies are more common in wild-caught starlings.