WorldWideScience

Sample records for cubic feet mcf

  1. What will we do with 104,000,000 cubic feet of Fernald waste?

    Energy Technology Data Exchange (ETDEWEB)

    Motl, G.P.; Krieger, G.J. [Fernald Environmental Restoration Management Corp., Cincinnati, OH (United States). Fernald Environmental Management Project; Rast, D.M. [USDOE Fernald Area Office, OH (United States)

    1995-04-01

    The Fernald Site, a Department of Energy (DOE) uranium metal production facility that ceased production in 1989, is now being remediated by the DOE under terms of a Consent Agreement with the United States Environmental Protection Agency (USEPA) and a Consent Decree with the State of Ohio. It is estimated that the cleanup will generate 104,000,000 cubic feet of low-level radioactive waste including construction debris, pit sludge, radium residue and a huge volume of uranium contaminated soil. The waste handling strategy for this huge volume of waste includes minimizing remedial waste generation, recycling material when economically feasible, free-releasing clean material and volume reduction. It is anticipated that large scale radium residue vitrification and sludge drying equipment/facilities will be constructed onsite for waste treatment prior to off-site disposal. Fernald waste disposition will include both onsite disposal (if approved under CERCLA) and off-site disposal at both commercial and DOE waste disposal facilities. The waste disposition strategy selected reflects a diverse variety of technical, political, regulatory and economic factors. This presentation will describe the current views at Fernald on {open_quotes}what will we do with 104,000,000 cubic feet of Fernald waste.{close_quotes}

  2. Prosthetic Feet

    Science.gov (United States)

    ... for optional PDF format. Requires Adobe Acrobat Reader Text size Larger text Smaller text Java Required Print page Save and share Favorites ... to the hip) reduce the effort needed to control a prosthesis and keep the knee from ... need periodic repair and cost a little more than most basic feet are ...

  3. Sweaty Feet (Hyperhidrosis)

    Science.gov (United States)

    ... Feet? Excessive sweating of the feet is called hyperhidrosis. It's more common in men than in women, ... sweating of the palms. According to the International Hyperhidrosis Society, 3 percent of the population suffers from ...

  4. Why Do Feet Stink?

    Science.gov (United States)

    ... of plastic. Plastic and some human-made materials don't let your feet breathe. Go barefoot. Let your feet air out by letting them spend some time in the open air, especially at night. But don't go barefoot too much — especially in the outdoors — because ...

  5. Arthritis and the Feet

    Science.gov (United States)

    ... RSS Home » Learn About Feet » Foot Health Information Arthritis What is Arthritis? Arthritis, in general terms, is inflammation and swelling of ... an increase in the fluid in the joints. Arthritis has multiple causes; just as a sore throat ...

  6. Design with the feet

    DEFF Research Database (Denmark)

    Kanstrup, Anne Marie; Bertelsen, Pernille; Madsen, Jacob Østergaard

    2014-01-01

    This paper presents an analysis of walking methods and their relation to participatory design (PD). The paper includes a study of walking methods found in the literature and an empirical study of transect walks in a PD project. From this analysis, we identify central attributes of, and challenges....... With this study, we take a step towards a methodological framework for "design with the feet" in PD....

  7. Why do our feet smell?

    Institute of Scientific and Technical Information of China (English)

    杨路晴

    2008-01-01

    Every night when we take off our socks and shoes,our feet smell(发出气味).The problem begjns when bacteria(细菌)are attracted(吸引)to the sweat on your feet and start eating it.The bacteria’s excretion(排泄物)has a strong smell.It causes your feet to smell badly.

  8. Bicontinuous cubic liquid crystalline nanoparticles for oral delivery of Doxorubicin

    DEFF Research Database (Denmark)

    Swarnakar, Nitin K; Thanki, Kaushik; Jain, Sanyog

    2014-01-01

    PURPOSE: The present study explores the potential of bicontinous cubic liquid crystalline nanoparticles (LCNPs) for improving therapeutic potential of doxorubicin. METHODS: Phytantriol based Dox-LCNPs were prepared using hydrotrope method, optimized for various formulation components, process...... variables and lyophilized. Structural elucidation of the reconstituted formulation was performed using HR-TEM and SAXS analysis. The developed formulation was subjected to exhaustive cell culture experiments for delivery potential (Caco-2 cells) and efficacy (MCF-7 cells). Finally, in vivo pharmacokinetics...

  9. Cubic Subalgebras and Cubic Closed Ideals of B-algebras

    Directory of Open Access Journals (Sweden)

    Tapan Senapati

    2015-06-01

    Full Text Available In this paper, the concept of cubic set to subalgebras, ideals and closed ideals of B-algebras are introduced. Relations among cubic subalgebras with cubic ideals and cubic closed ideals of B-algebras investigated. The homomorphic image and inverse image of cubic subalgebras, ideals are studied and some related properties are investigated. Also, the product of cubic B-algebras are investigated.

  10. Einsteinian cubic gravity

    Science.gov (United States)

    Bueno, Pablo; Cano, Pablo A.

    2016-11-01

    We drastically simplify the problem of linearizing a general higher-order theory of gravity. We reduce it to the evaluation of its Lagrangian on a particular Riemann tensor depending on two parameters, and the computation of two derivatives with respect to one of those parameters. We use our method to construct a D -dimensional cubic theory of gravity which satisfies the following properties: (1) it shares the spectrum of Einstein gravity, i.e., it only propagates a transverse and massless graviton on a maximally symmetric background; (2) it is defined in the same way in general dimensions; (3) it is neither trivial nor topological in four dimensions. Up to cubic order in curvature, the only previously known theories satisfying the first two requirements are the Lovelock ones. We show that, up to cubic order, there exists only one additional theory satisfying requirements (1) and (2). Interestingly, this theory is, along with Einstein gravity, the only one which also satisfies (3).

  11. Guarded Cubical Type Theory

    DEFF Research Database (Denmark)

    Birkedal, Lars; Bizjak, Aleš; Clouston, Ranald;

    2016-01-01

    This paper improves the treatment of equality in guarded dependent type theory (GDTT), by combining it with cubical type theory (CTT). GDTT is an extensional type theory with guarded recursive types, which are useful for building models of program logics, and for programming and reasoning with co...

  12. Guarded Cubical Type Theory

    DEFF Research Database (Denmark)

    Birkedal, Lars; Bizjak, Aleš; Clouston, Ranald;

    2016-01-01

    This paper improves the treatment of equality in guarded dependent type theory (GDTT), by combining it with cubical type theory (CTT). GDTT is an extensional type theory with guarded recursive types, which are useful for building models of program logics, and for programming and reasoning...... with coinductive types. We wish to implement GDTT with decidable type-checking, while still supporting non-trivial equality proofs that reason about the extensions of guarded recursive constructions. CTT is a variation of Martin-L\\"of type theory in which the identity type is replaced by abstract paths between...... terms. CTT provides a computational interpretation of functional extensionality, is conjectured to have decidable type checking, and has an implemented type-checker. Our new type theory, called guarded cubical type theory, provides a computational interpretation of extensionality for guarded recursive...

  13. Guarded Cubical Type Theory

    DEFF Research Database (Denmark)

    Birkedal, Lars; Bizjak, Aleš; Clouston, Ranald;

    2016-01-01

    This paper improves the treatment of equality in guarded dependent type theory (GDTT), by combining it with cubical type theory (CTT). GDTT is an extensional type theory with guarded recursive types, which are useful for building models of program logics, and for programming and reasoning...... with coinductive types. We wish to implement GDTT with decidable type checking, while still supporting non-trivial equality proofs that reason about the extensions of guarded recursive constructions. CTT is a variation of Martin-L\\"of type theory in which the identity type is replaced by abstract paths between...... terms. CTT provides a computational interpretation of functional extensionality, enjoys canonicity for the natural numbers type, and is conjectured to support decidable type-checking. Our new type theory, guarded cubical type theory (GCTT), provides a computational interpretation of extensionality...

  14. Diabetes - taking care of your feet

    Science.gov (United States)

    Diabetes - foot care - self-care; Diabetic foot ulcer - foot care; Diabetic neuropathy - foot care ... Diabetes can damage the nerves and blood vessels in your feet. This damage can cause numbness and ...

  15. Towards gecko-feet-inspired bandages.

    Science.gov (United States)

    Yanik, Mehmet Fatih

    2009-01-01

    A novel bandage inspired by gecko feet might one day be used during emergencies and internal surgeries. The bandage uses a combination of nanofabricated structures, biodegradable materials and adhesive surface chemistry that allows adhesion onto even wet, moving tissue.

  16. Anisotropic cubic curvature couplings

    CERN Document Server

    Bailey, Quentin G

    2016-01-01

    To complement recent work on tests of spacetime symmetry in gravity, cubic curvature couplings are studied using an effective field theory description of spacetime-symmetry breaking. The associated mass dimension 8 coefficients for Lorentz violation studied do not result in any linearized gravity modifications and instead are revealed in the first nonlinear terms in an expansion of spacetime around a flat background. We consider effects on gravitational radiation through the energy loss of a binary system and we study two-body orbital perturbations using the post-Newtonian metric. Some effects depend on the internal structure of the source and test bodies, thereby breaking the Weak Equivalence Principle for self-gravitating bodies. These coefficients can be measured in solar-system tests, while binary-pulsar systems and short-range gravity tests are particularly sensitive.

  17. Managing Friction Blisters of the Feet.

    Science.gov (United States)

    Ramsey, M L

    1992-01-01

    In brief Active people often develop friction blisters on their feet. Although such blisters rarely create significant medical problems, they can be quite painful and can hinder athletic performance. People can decrease the chance of blister formation by wearing properly fitting shoes, doubling up on socks, and applying dressings or lubricants. If lesions do develop, conservative treatment will speed healing and lessen pain and disability.

  18. Chondroblastoma of the hands and feet

    Energy Technology Data Exchange (ETDEWEB)

    Davila, Jesse A.; Amrami, Kimberly K.; Sundaram, Murali; Adkins, Mark C. [Mayo Clinic, Department of Radiology, Rochester (United States); Unni, Krishnan K. [Mayo Clinic, Department of Surgical Pathology, Rochester (United States)

    2004-10-01

    To review the imaging findings, age and gender distribution of chondroblastoma of the hands and feet. Twenty-five cases of pathologically proven chondroblastoma of the hands and feet were reviewed. Available imaging modalities included radiographs (n=24), CT (n=3), MRI (n=5), and radionuclide bone scintigraphy (n=1). The following imaging features for each case were tabulated: location, presence of sclerotic margin, calcification, expansion, presence of fluid/fluid levels on cross-sectional imaging and surrounding edema on MRI. The images were evaluated for skeletal maturity using closure of the physeal plate in the region as a standard. The average age at time of diagnosis was 23 years (range 7-57 years). Eighty-four percent (n=21) of the patients were skeletally mature. Males (20 of 25) outnumbered females by a ratio of 5:1. The bones of the foot accounted for 22 cases: calcaneus (n=8), talus (n=8), metatarsals (n=3), and the cuboid (n=3). The bones of the hand accounted for three cases: phalanx (n=1), triquetrum (n=1), and a metacarpal (n=1). Radiographically all lesions were osteolytic with identifiable calcification in 54% (13 of 24). Fluid/fluid levels were seen in four of five cases on MRI. Edema on MR images was seen in 40% (2 of 5). The size of the lesions ranged from 2 to 41 cm{sup 2}. Chondroblastomas of the hands and feet share many of the radiographic characteristics seen in the long bones, but manifest in skeletally mature patients with a higher male to female ratio than in long bone chondroblastoma. Talar and calcaneal lesions were encountered only in males. Chondroblastoma of the wrist and hand appears to be exceptionally rare. (orig.)

  19. A Cubic Tree Taper Model

    National Research Council Canada - National Science Library

    Goodwin, Adrian N

    2009-01-01

    A flexible tree taper model based on a cubic polynomial is described. It is algebraically invertible and integrable, and can be constrained by one or two diameters, neither of which need be diameter at breast height (DBH...

  20. Universal Reconfiguration of (Hyper-)cubic Robots

    OpenAIRE

    Abel, Zachary; Kominers, Scott D.

    2008-01-01

    We study a simple reconfigurable robot model which has not been previously examined: cubic robots comprised of three-dimensional cubic modules which can slide across each other and rotate about each others' edges. We demonstrate that the cubic robot model is universal, i.e., that an n-module cubic robot can reconfigure itself into any specified n-module configuration. Additionally, we provide an algorithm that efficiently plans and executes cubic robot motion. Our results directly extend to a...

  1. Malignant MCF10CA1 cell lines derived from premalignant human breast epithelial MCF10AT cells.

    Science.gov (United States)

    Santner, S J; Dawson, P J; Tait, L; Soule, H D; Eliason, J; Mohamed, A N; Wolman, S R; Heppner, G H; Miller, F R

    2001-01-01

    The MCF10 series of cell lines was derived from benign breast tissue from a woman with fibrocystic disease. The MCF10 human breast epithelial model system consists of mortal MCF10M and MCF10MS (mortal cells grown in serum-free and serum-containing media, respectively), immortalized but otherwise normal MCF10F and MCF10A lines (free-floating versus growth as attached cells), transformed MCF10AneoT cells transfected with T24 Ha-ras, and premalignant MCF10AT cells with potential for neoplastic progression. The MCF10AT, derived from xenograft-passaged MCF10-AneoT cells, generates carcinomas in approximately 25% of xenografts. We now report the derivation of fully malignant MCF10CA1 lines that complete the spectrum of progression from relatively normal breast epithelial cells to breast cancer cells capable of metastasis. MCF10CA1 lines display histologic variations ranging from undifferentiated carcinomas, sometimes with focal squamous differentiation, to well-differentiated adenocarcinomas. At least two metastasize to the lung following injection of cells into the tail vein; one line grows very rapidly in the lung, with animals moribund within 4 weeks, whereas the other requires 15 weeks to reach the same endpoint. In addition to variations in efficiency of tumor production, the MCF10CA1 lines show differences in morphology in culture, anchorage-independent growth, karyotype, and immunocytochemistry profiles. The MCF10 model provides a unique tool for the investigation of molecular changes during progression of human breast neoplasia and the generation of tumor heterogeneity on a common genetic background.

  2. Cubication of Conservative Nonlinear Oscillators

    Science.gov (United States)

    Belendez, Augusto; Alvarez, Mariela L.; Fernandez, Elena; Pascual, Immaculada

    2009-01-01

    A cubication procedure of the nonlinear differential equation for conservative nonlinear oscillators is analysed and discussed. This scheme is based on the Chebyshev series expansion of the restoring force, and this allows us to approximate the original nonlinear differential equation by a Duffing equation in which the coefficients for the linear…

  3. Cryptographic Analysis in Cubic Time

    DEFF Research Database (Denmark)

    Nielson, Flemming; Nielson, Hanne Riis; Seidl, H.

    2004-01-01

    The spi-calculus is a variant of the polyadic pi-calculus that admits symmetric cryptography and that admits expressing communication protocols in a precise though still abstract way. This paper shows that context-independent control flow analysis can be calculated in cubic time despite the fact ...

  4. The diagonalization of cubic matrices

    Science.gov (United States)

    Cocolicchio, D.; Viggiano, M.

    2000-08-01

    This paper is devoted to analysing the problem of the diagonalization of cubic matrices. We extend the familiar algebraic approach which is based on the Cardano formulae. We rewrite the complex roots of the associated resolvent secular equation in terms of transcendental functions and we derive the diagonalizing matrix.

  5. Protection of feet in cold exposure.

    Science.gov (United States)

    Kuklane, Kalev

    2009-07-01

    The paper summarizes the research on cold protection of feet. There exist several conflicting requirements for the choice of the best suited footwear for cold exposure. These conflicts are related to various environmental factors, protection needs and user comfort issues. In order to reduce such conflicts and simplify the choice of proper footwear the paper suggests dividing the cold into specific ranges that are related to properties and state of water and its possibility to penetrate into, evaporate from or condensate in footwear. The thermo-physiological background and reactions in foot are briefly explained, and main problems and risks related to cold injuries, mechanical injuries and slipping discussed. Footwear thermal insulation is the most important factor for protection against cold. The issues related to measuring the insulation and the practical use of measured values are described, but also the effect of socks, and footwear size. Other means for reducing heat losses, such as PCM and electrical heating are touched. The most important variable that affects footwear thermal insulation and foot comfort is moisture in footwear. In combination with motion they may reduce insulation and thus protection against cold by 45%. The paper includes recommendations for better foot comfort in cold.

  6. Study on new float polishing with the MCF

    OpenAIRE

    Shimada, K.; Matsuo, Y.; Yamamoto, K; Zheng, Y.

    2007-01-01

    Purpose: As a continuation of a previous paper [1], the report demonstrates the various possibilities of float polishing utilizing the present improved magnetic compound fluid (MCF). The MCF developed by one of authors, Shimada, in 2001, was improved by the addition of α-cellulose, thereby achieving a clearance as great as 8mm as shown in another paper [1]. The present paper describes the possibility of the application of the MCF float polishing technique with α-cellulose.Design/methodology/a...

  7. From the Field: Carbofuran detected on weathered raptor carcass feet

    Science.gov (United States)

    Vyas, N.B.; Spann, J.W.; Hulse, C.S.; Bauer, W.; Olson, S.

    2005-01-01

    The cause of death for raptors poisoned at illegal carbofuran-Iaced predator baits is often not confirmed because the carcass matrices that are conventionally analyzed are not available due to decomposition and scavenging. However, many such carcasses retain intact feet that may have come into contact with carbofuran. Eastern screech owls (Otus asio) were exposed to carbofuran via simulated predator baits. Detection of carbofuran from owl feet weathered for 28 days demonstrated the temporal reliability of using feet during a forensic investigation. Raptor carcasses previously not submitted for residue analysis because of a lack of the conventional matrices may now be salvaged for their feet.

  8. Cubication of conservative nonlinear oscillators

    Energy Technology Data Exchange (ETDEWEB)

    Belendez, Augusto; Alvarez, Mariela L [Departamento de Fisica, Ingenieria de Sistemas y Teoria de la Senal, Universidad de Alicante, Apartado 99, E-03080 Alicante (Spain); Fernandez, Elena; Pascual, Inmaculada [Departamento de Optica, FarmacologIa y Anatomia, Universidad de Alicante, Apartado 99, E-03080 Alicante (Spain)], E-mail: a.belendez@ua.es

    2009-09-15

    A cubication procedure of the nonlinear differential equation for conservative nonlinear oscillators is analysed and discussed. This scheme is based on the Chebyshev series expansion of the restoring force, and this allows us to approximate the original nonlinear differential equation by a Duffing equation in which the coefficients for the linear and cubic terms depend on the initial amplitude, A, while in a Taylor expansion of the restoring force these coefficients are independent of A. The replacement of the original nonlinear equation by an approximate Duffing equation allows us to obtain an approximate frequency-amplitude relation as a function of the complete elliptic integral of the first kind. Some conservative nonlinear oscillators are analysed to illustrate the usefulness and effectiveness of this scheme.

  9. Cubic Matrix, Nambu Mechanics and Beyond

    OpenAIRE

    Kawamura, Y

    2002-01-01

    We propose a generalization of cubic matrix mechanics by introducing a canonical triplet and study its relation to Nambu mechanics. The generalized cubic matrix mechanics we consider can be interpreted as a “quantum” generalization of Nambu mechanics.

  10. Cubical sets and the topological topos

    DEFF Research Database (Denmark)

    Spitters, Bas

    2016-01-01

    Coquand's cubical set model for homotopy type theory provides the basis for a computational interpretation of the univalence axiom and some higher inductive types, as implemented in the cubical proof assistant. This paper contributes to the understanding of this model. We make three contributions...... show that it can also be a target for cubical realization by showing that Coquand's cubical sets classify the geometric theory of flat distributive lattices. As a side result, we obtain a simplicial realization of a cubical set. 2. Using the internal `interval' in the topos of cubical sets, we...... construct a Moore path model of identity types. 3. We construct a premodel structure internally in the cubical type theory and hence on the fibrant objects in cubical sets....

  11. Numbers for reducible cubic scrolls

    Directory of Open Access Journals (Sweden)

    Israel Vainsencher

    2004-12-01

    Full Text Available We show how to compute the number of reducible cubic scrolls of codimension 2 in (math blackboard symbol Pn incident to the appropriate number of linear spaces.Mostramos como calcular o número de rolos cúbicos redutíveis de codimensão 2 em (math blackboard symbol Pn incidentes a espaços lineares apropriados.

  12. Probing micro-environment of lipid droplets in a live breast cell: MCF7 and MCF10A

    Science.gov (United States)

    Ghosh, Catherine; Nandi, Somen; Bhattacharyya, Kankan

    2017-02-01

    Local environment of the lipid droplets inside the breast cancer cells, MCF7 and in non-malignant breast cells, MCF10A is monitored using time-resolved confocal microscopy. For this study, a coumarin-based dye C153 has been used. The local polarity and the solvation dynamics indicate that a cytoplasmic lipid droplet is less polar and displays slower solvation dynamics compared to the cytosol. Significant differences in terms of number of lipid droplets, polarity and solvation dynamics are observed between the cancer cell (MCF7) and its non-malignant cell (MCF10A).

  13. Career in Feet-on Seismology

    Science.gov (United States)

    Van der Lee, S.

    2011-12-01

    My career award was for imaging the upper mantle beneath North America. The research proposed was timely because of Earthscope and novel because of the proposed simultaneous inversion of different types of seismic data as well as the inclusion of mineral physics data on the effects of volatiles on seismic properties of the mantle. This research has been challenging and fun and is still on-going. The educational component of my career award consists of feet-on and eyes-open learning of seismology through an educational kiosk and field trips to actual seismic stations. The kiosk and field station have both been growing over the years, as has the audience. I started with the field station in-doors, so it doubled as the kiosk along with a palmtop terminal. Groups of minority elementary school children would look at the mysterious hardware of the "field" station and then jump up and down so they could awe at the peaks in the graph on the palmtop screen that they created. This has evolved into a three-screen kiosk, of which one screen is a touch screen along with a demonstration seismometer. The field station is now in a goat shed near the epicenter of an actual 2010 earthquake inIllinois, which is soon to be replaced by a TA station of Earthscope. The audience has grown to entire grades of middle-school children and activities have evolved from jumping to team-experimentation and the derivation of amplitude-distance relationships following a collaborative curriculum. Addressing the questions in the session description: 1) Education is more fun and effective when one can work in a team with an enthusiastic educator. 2) My education activities are strongly related to my field of expertise but very loosely related to the research carried out with the career award. It appears that not the research outcomes are of interest to students, but instead the simplification and accessibility of the process of research that is of interest. 3) The education component of the career

  14. Cubic colloids : Synthesis, functionalization and applications

    NARCIS (Netherlands)

    Castillo, S.I.R.

    2015-01-01

    This thesis is a study on cubic colloids: micron-sized cubic particles with rounded corners (cubic superballs). Owing to their shape, particle packing for cubes is more efficient than for spheres and results in fascinating phase and packing behavior. For our cubes, the particle volume fraction when

  15. Cubic colloids : Synthesis, functionalization and applications

    NARCIS (Netherlands)

    Castillo, S.I.R.

    2015-01-01

    This thesis is a study on cubic colloids: micron-sized cubic particles with rounded corners (cubic superballs). Owing to their shape, particle packing for cubes is more efficient than for spheres and results in fascinating phase and packing behavior. For our cubes, the particle volume fraction when

  16. Solving Cubic Equations by Polynomial Decomposition

    Science.gov (United States)

    Kulkarni, Raghavendra G.

    2011-01-01

    Several mathematicians struggled to solve cubic equations, and in 1515 Scipione del Ferro reportedly solved the cubic while participating in a local mathematical contest, but did not bother to publish his method. Then it was Cardano (1539) who first published the solution to the general cubic equation in his book "The Great Art, or, The Rules of…

  17. Cubic Icosahedra? A Problem in Assigning Symmetry

    Science.gov (United States)

    Lloyd, D. R.

    2010-01-01

    There is a standard convention that the icosahedral groups are classified separately from the cubic groups, but these two symmetry types have been conflated as "cubic" in some chemistry textbooks. In this note, the connection between cubic and icosahedral symmetries is examined, using a simple pictorial model. It is shown that octahedral and…

  18. Cubic metaplectic forms and theta functions

    CERN Document Server

    Proskurin, Nikolai

    1998-01-01

    The book is an introduction to the theory of cubic metaplectic forms on the 3-dimensional hyperbolic space and the author's research on cubic metaplectic forms on special linear and symplectic groups of rank 2. The topics include: Kubota and Bass-Milnor-Serre homomorphisms, cubic metaplectic Eisenstein series, cubic theta functions, Whittaker functions. A special method is developed and applied to find Fourier coefficients of the Eisenstein series and cubic theta functions. The book is intended for readers, with beginning graduate-level background, interested in further research in the theory of metaplectic forms and in possible applications.

  19. Steroid metabolism in the hormone dependent MCF-7 human breast carcinoma cell line and its two hormone resistant subpopulations MCF-7/LCC1 and MCF-7/LCC2

    DEFF Research Database (Denmark)

    Jørgensen, L; Brünner, N; Spang-Thomsen, M

    1998-01-01

    and 17beta-hydroxysteroid oxidoreductase were investigated isolating the following steroids: estriol (E3), estradiol (E2), estrone (E1), 3alpha/beta-androstanediol (A-diol), testosterone (T), dihydrotestosterone (DHT), androsterone (AND), androstenedion (4-AD) and androstanedione (A-dion). For all......, and preincubation with cortisol had no effect on the enzyme activity. With [14C]T as the substrate, the metabolized level of DHT was very similar in the three cell lines, though MCF-7/LCC1 and MCF-7/LCC2 utilized the substrate to a much lesser extent. The amount of DHT and 4-AD produced were comparable in the two...... to the parent MCF-7. However, since treatment with DHT and T inhibited cell growth equally well in all three tumor cell lines, it is unlikely that the found differences in steroid metabolism was involved in the acquisition of the endocrine resistance of the two MCF-7 sublines....

  20. Weighted cubic and biharmonic splines

    Science.gov (United States)

    Kvasov, Boris; Kim, Tae-Wan

    2017-01-01

    In this paper we discuss the design of algorithms for interpolating discrete data by using weighted cubic and biharmonic splines in such a way that the monotonicity and convexity of the data are preserved. We formulate the problem as a differential multipoint boundary value problem and consider its finite-difference approximation. Two algorithms for automatic selection of shape control parameters (weights) are presented. For weighted biharmonic splines the resulting system of linear equations can be efficiently solved by combining Gaussian elimination with successive over-relaxation method or finite-difference schemes in fractional steps. We consider basic computational aspects and illustrate main features of this original approach.

  1. Transparent polycrystalline cubic silicon nitride

    Science.gov (United States)

    Nishiyama, Norimasa; Ishikawa, Ryo; Ohfuji, Hiroaki; Marquardt, Hauke; Kurnosov, Alexander; Taniguchi, Takashi; Kim, Byung-Nam; Yoshida, Hidehiro; Masuno, Atsunobu; Bednarcik, Jozef; Kulik, Eleonora; Ikuhara, Yuichi; Wakai, Fumihiro; Irifune, Tetsuo

    2017-01-01

    Glasses and single crystals have traditionally been used as optical windows. Recently, there has been a high demand for harder and tougher optical windows that are able to endure severe conditions. Transparent polycrystalline ceramics can fulfill this demand because of their superior mechanical properties. It is known that polycrystalline ceramics with a spinel structure in compositions of MgAl2O4 and aluminum oxynitride (γ-AlON) show high optical transparency. Here we report the synthesis of the hardest transparent spinel ceramic, i.e. polycrystalline cubic silicon nitride (c-Si3N4). This material shows an intrinsic optical transparency over a wide range of wavelengths below its band-gap energy (258 nm) and is categorized as one of the third hardest materials next to diamond and cubic boron nitride (cBN). Since the high temperature metastability of c-Si3N4 in air is superior to those of diamond and cBN, the transparent c-Si3N4 ceramic can potentially be used as a window under extremely severe conditions. PMID:28303948

  2. Microbiological evaluation of chicken feet intended for human consumption

    Directory of Open Access Journals (Sweden)

    Ana Paula Dutra Resem Brizio

    2013-12-01

    Full Text Available Chicken feet are products with great commercial importance for the eastern markets. Although Brazil is a large exporter of these products to those markets, little information is available on the sanitary quality of these products. The objective of this study was to evaluate the microbiological quality of frozen chicken feet for human consumption. This study was developed in a slaughterhouse under Federal Inspection, located in the state of Rio Grande do Sul. A total of 98 samples of frozen chicken feet were analyzed, between January and December 2011, for the detection of Salmonella spp., total count of mesophilic bacteria, total coliforms, fecal coliforms, Escherichia coli, Staphylococcus coagulase positive and Clostridium perfringens. About 99% of the results were within the microbiological standards established by the Chinese (world´s largest importer and Brazilian legislation for raw chicken meat. Thus, we conclude that the samples of frozen chicken feet showed satisfactory microbiological quality and no risk to consumer health.

  3. POSTURAL DISTURBANCES AND FEET DEFORMITIES IN CHILDREN WITH CEREBRAL PALSY

    Directory of Open Access Journals (Sweden)

    V. M. Kenis

    2011-01-01

    Full Text Available The purpose of study was to estimate common postural disturbances in children with cerebral palsy in relation to feet deformities. 100 children were investigated. Age-related changes in postural patterns are described. Five stereotypical postural patterns are most common in children with cerebral palsy. Proper management of feet deformities is necessary for correction of postural disturbance. Inadequate surgical treatment, as a contrast, may be harmfull and dangerous.

  4. POSTURAL DISTURBANCES AND FEET DEFORMITIES IN CHILDREN WITH CEREBRAL PALSY

    OpenAIRE

    V. M. Kenis; Ivanov, S V; Yu. A. Stepanova

    2011-01-01

    The purpose of study was to estimate common postural disturbances in children with cerebral palsy in relation to feet deformities. 100 children were investigated. Age-related changes in postural patterns are described. Five stereotypical postural patterns are most common in children with cerebral palsy. Proper management of feet deformities is necessary for correction of postural disturbance. Inadequate surgical treatment, as a contrast, may be harmfull and dangerous.

  5. Tame Kernels of Pure Cubic Fields

    Institute of Scientific and Technical Information of China (English)

    Xiao Yun CHENG

    2012-01-01

    In this paper,we study the p-rank of the tame kernels of pure cubic fields.In particular,we prove that for a fixed positive integer m,there exist infinitely many pure cubic fields whose 3-rank of the tame kernel equal to m.As an application,we determine the 3-rank of their tame kernels for some special pure cubic fields.

  6. Two-dimensional cubic convolution.

    Science.gov (United States)

    Reichenbach, Stephen E; Geng, Frank

    2003-01-01

    The paper develops two-dimensional (2D), nonseparable, piecewise cubic convolution (PCC) for image interpolation. Traditionally, PCC has been implemented based on a one-dimensional (1D) derivation with a separable generalization to two dimensions. However, typical scenes and imaging systems are not separable, so the traditional approach is suboptimal. We develop a closed-form derivation for a two-parameter, 2D PCC kernel with support [-2,2] x [-2,2] that is constrained for continuity, smoothness, symmetry, and flat-field response. Our analyses, using several image models, including Markov random fields, demonstrate that the 2D PCC yields small improvements in interpolation fidelity over the traditional, separable approach. The constraints on the derivation can be relaxed to provide greater flexibility and performance.

  7. Cubical local partial orders on cubically subdivided spaces - Existence and construction

    DEFF Research Database (Denmark)

    Fajstrup, Lisbeth

    2006-01-01

    The geometric models of higher dimensional automata (HDA) and Dijkstra's PV-model are cubically subdivided topological spaces with a local partial order. If a cubicalization of a topological space is free of immersed cubic Möbius bands, then there are consistent choices of direction in all cubes...

  8. Cubical local partial orders on cubically subdivided spaces - existence and construction

    DEFF Research Database (Denmark)

    Fajstrup, Lisbeth

    The geometric models of Higher Dimensional Automata and Dijkstra's PV-model are cubically subdivided topological spaces with a local partial order. If a cubicalization of a topological space is free of immersed cubic Möbius bands, then there are consistent choices of direction in all cubes...

  9. CLASSIFICATION OF CUBIC PARAMETERIZED HOMOGENEOUS VECTOR FIELDS

    Institute of Scientific and Technical Information of China (English)

    Karnal H.Yasir; TANG Yun

    2002-01-01

    In this paper the cubic homogeneous parameterized vector fields are studied.The classification of the phase portrait near the critical point is presented. This classification is an extension of the result given by Takens to the cubic homogeneous parameterized vector fields with six parameters.

  10. CLASSIFICATION OF CUBIC PARAMETERIZED HOMOGENEOUS VECTOR FIELDS

    Institute of Scientific and Technical Information of China (English)

    KamalH.Yasir; TNAGYun

    2002-01-01

    In this paper the cubic homogeneous parameterized vector fields are studied.The classification of the phase portrait near the critical point is presented.This classification is an extension of the result given by takens to the cubic homogeneous parameterized vector fields with six parameters.

  11. Evidence of a Genomic Biomarker in Normal Human Epithelial Mammary Cell Line, MCF-10A, That Is Absent in the Human Breast Cancer Cell Line, MCF-7

    Directory of Open Access Journals (Sweden)

    Brian H. Crawford

    2006-01-01

    MCF-7 cells, it was transfected into MCF-7 cells. There were observable changes in the morphology of the transfected cells. These changes included an increase in cell elongation and a decrease in cell aggregation.

  12. Fibromatosis over the dorsa of both feet: An unusual presentation

    Science.gov (United States)

    Kishan Kumar, Y. Hari; Sujatha, C.; Jayaprasad, Sushmitha

    2015-01-01

    Fibromatosis is benign fibrous tissue condition intermediate between benign fibroma and metastasizing fibrosarcoma. The lesion tends to infiltrate and recur when removed, but do not metastasize. The lesion may be single or multiple, and the likelihood of recurrence after surgical removal varies with location of the lesion and age. A 40-year-old female presented with multiple raised lesions over both feet since 4 years, they were multiple well-defined firm nodules coalescing to form lobulated plaques distributed in a symmetrical pattern over the dorsum of both feet. Histopathology of skin showed epidermis with hyperkeratosis, acanthosis, mild parakeratosis, and prominent granular layer. Superficial dermis was unremarkable and deep dermis showed thick bundles of irregular collagen and fibroblastic proliferation, suggestive of fibromatosis. This case is being reported for its unusual presentation of fibromatosis over the dorsum of both feet. PMID:25821730

  13. Ultrahard nanotwinned cubic boron nitride.

    Science.gov (United States)

    Tian, Yongjun; Xu, Bo; Yu, Dongli; Ma, Yanming; Wang, Yanbin; Jiang, Yingbing; Hu, Wentao; Tang, Chengchun; Gao, Yufei; Luo, Kun; Zhao, Zhisheng; Wang, Li-Min; Wen, Bin; He, Julong; Liu, Zhongyuan

    2013-01-17

    Cubic boron nitride (cBN) is a well known superhard material that has a wide range of industrial applications. Nanostructuring of cBN is an effective way to improve its hardness by virtue of the Hall-Petch effect--the tendency for hardness to increase with decreasing grain size. Polycrystalline cBN materials are often synthesized by using the martensitic transformation of a graphite-like BN precursor, in which high pressures and temperatures lead to puckering of the BN layers. Such approaches have led to synthetic polycrystalline cBN having grain sizes as small as ∼14 nm (refs 1, 2, 4, 5). Here we report the formation of cBN with a nanostructure dominated by fine twin domains of average thickness ∼3.8 nm. This nanotwinned cBN was synthesized from specially prepared BN precursor nanoparticles possessing onion-like nested structures with intrinsically puckered BN layers and numerous stacking faults. The resulting nanotwinned cBN bulk samples are optically transparent with a striking combination of physical properties: an extremely high Vickers hardness (exceeding 100 GPa, the optimal hardness of synthetic diamond), a high oxidization temperature (∼1,294 °C) and a large fracture toughness (>12 MPa m(1/2), well beyond the toughness of commercial cemented tungsten carbide, ∼10 MPa m(1/2)). We show that hardening of cBN is continuous with decreasing twin thickness down to the smallest sizes investigated, contrasting with the expected reverse Hall-Petch effect below a critical grain size or the twin thickness of ∼10-15 nm found in metals and alloys.

  14. Cubic III-nitrides: potential photonic materials

    Science.gov (United States)

    Onabe, K.; Sanorpim, S.; Kato, H.; Kakuda, M.; Nakamura, T.; Nakamura, K.; Kuboya, S.; Katayama, R.

    2011-01-01

    The growth and characterization of some cubic III-nitride films on suitable cubic substrates have been done, namely, c- GaN on GaAs by MOVPE, c-GaN and c-AlGaN on MgO by RF-MBE, and c-InN and c-InGaN (In-rich) on YSZ by RFMBE. This series of study has been much focused on the cubic-phase purity as dependent on the respective growth conditions and resulting electrical and optical properties. For c-GaN and c-InN films, a cubic-phase purity higher than 95% is attained in spite of the metastable nature of the cubic III-nitrides. However, for c-AlGaN and c-InGaN films, the cubic-phase purity is rapidly degraded with significant incorporation of the hexagonal phase through stacking faults on cubic {111} faces which may be exposed on the roughened growing or substrate surface. It has been shown that the electron mobilities in c-GaN and c-AlGaN films are much related to phase purity.

  15. Cubic Curves, Finite Geometry and Cryptography

    CERN Document Server

    Bruen, A A; Wehlau, D L

    2011-01-01

    Some geometry on non-singular cubic curves, mainly over finite fields, is surveyed. Such a curve has 9,3,1 or 0 points of inflexion, and cubic curves are classified accordingly. The group structure and the possible numbers of rational points are also surveyed. A possible strengthening of the security of elliptic curve cryptography is proposed using a `shared secret' related to the group law. Cubic curves are also used in a new way to construct sets of points having various combinatorial and geometric properties that are of particular interest in finite Desarguesian planes.

  16. Generalized Vaidya spacetime for cubic gravity

    CERN Document Server

    Ruan, Shan-Ming

    2015-01-01

    We present a kind of generalized Vaidya solutions of a new cubic gravity in five dimensions whose field equations in spherically spacetime are always second order like the Lovelock gravity. We also study the thermodynamics of its apparent horizon and get its entropy expression and generalized Misner-Sharp energy. Finally we present the first law and second law hold in this gravity. Although all the results are analogue to those in Lovelock gravity, we in fact introduce the contribution of new cubic term in five dimensions where cubic Lovelock term is just zero.

  17. Cubical sets as a classifying topos

    DEFF Research Database (Denmark)

    Spitters, Bas

    Coquand’s cubical set model for homotopy type theory provides the basis for a computational interpretation of the univalence axiom and some higher inductive types, as implemented in the cubical proof assistant. We show that the underlying cube category is the opposite of the Lawvere theory of De...... Morgan algebras. The topos of cubical sets itself classifies the theory of ‘free De Morgan algebras’. This provides us with a topos with an internal ‘interval’. Using this interval we construct a model of type theory following van den Berg and Garner. We are currently investigating the precise relation...

  18. Patch testing in contact dermatitis of hands and feet

    Directory of Open Access Journals (Sweden)

    Huda M

    1996-01-01

    Full Text Available Eighty clinically diagnosed cases of allergic contact dermatitis of hands and feet when subjected to patch testing, Seventy four (92.5% cases showed positive patch test reactions to different suspected antigens. Maximum number of cases belonged to housewives and tea garden workers which showed positive patch test reaction to vegetables and soaps and detergents and pesticides, respectively.

  19. Comparative roll-over analysis of prosthetic feet

    NARCIS (Netherlands)

    Curtze, Carolin; Hof, At L.; van Keeken, Helco G.; Halbertsma, Jan P. K.; Postema, Klaas; Otten, Bert

    2009-01-01

    A prosthetic foot is a key element of a prosthetic leg, literally forming the basis for a stable and efficient amputee gait. We determined the roll-over characteristics of a broad range of prosthetic feet and examined the effect of a variety of shoes on these characteristics. The body weight of a pe

  20. Advances in Propulsive Bionic Feet and Their Actuation Principles

    Directory of Open Access Journals (Sweden)

    Pierre Cherelle

    2014-07-01

    Full Text Available In the past decades, researchers have deeply studied pathological and nonpathological gait to understand the human ankle function during walking. These efforts resulted in the development of new lower limb prosthetic devices aiming at raising the 3C-level (control, comfort, and cosmetics of amputees. Thanks to the technological advances in engineering and mechatronics, challenges in the field of prosthetics have become an important source of interest for roboticists. Currently, most of the bionic feet are still on a research level but show promising results and a preview of tomorrow's commercial prosthetic devices. In this paper, the authors present the current state-of-the-art and the latest advances in propulsive bionic feet with its actuation principles. The context of this review study is outlined followed by a brief description of the basics in human biomechanics and criteria for new prosthetic designs. A new categorization based on the actuation principle of propulsive ankle-foot prostheses is proposed. Based on simulations, the general principles and benefits of each actuation method are explained. The corresponding latest advances in propulsive bionic feet are presented together with their main characteristics and scientific outcomes. The authors also propose to the reader a comparison analysis of the presented devices with a discussion of the general tendencies in new prosthetic feet.

  1. Burning feet syndrome: An old tropical syndrome revisited

    Directory of Open Access Journals (Sweden)

    Ellen Welch

    2013-01-01

    Full Text Available Background: Burning feet syndrome (BFS has been described anecdotally in the literature for over 200 years. Described subjectively by patients as burning, prickling and unremitting with nocturnal exacerbations, the condition draws parallels with the burning dysaesthesia found in diabetic peripheral neuropathy, and appears to display a similar chronicity. Despite being a common symptom, especially among the elderly, its etiology in non-specific and often marked by a lack of objective clinical signs. Historically, burning feet syndrome has been recorded in situations of poor nutrition, including malnourished African populations in the early 20th century, South American plantation workers in the 1920s and during food shortages in the Spanish Civil War. Perhaps the best described and largest outbreak of burning feet occurred amongst prisoners of war (POWs of the Japanese during the 2nd World War in South East Asia and the Far East. In this review we summarise reports of the condition, in particular amongst Far East POWs (FEPOWs, using both the available literature as well as a unique and previously unknown contemporary study carried out in a POW camp. Materials and Methods: During his stay in the Tandjung Priok POW camp, Nowell Peach recorded 54 cases of burning feet seen over a 4 month period during captivity. This data was concealed from his captors and survived to return home with him. Results: 54 prisoners presented over a 4 month period with a mean age of 28 years and mean duration of symptoms of 12 weeks. Neurological signs were meticulously documented. All were on an inadequate diet, 20 (38% were on less than a full ration. Accompanying tropical infections were common including malaria (73%, dengue (45% and dysentery (41%. Discussions: The Peach survey confirmed the frequency of burning feet amongst FEPOWs and was unusual in that the neurological examination and conditions endured were documented in captivity. A paucity of physical signs was

  2. Flexible flat feet in children: a real problem?

    Science.gov (United States)

    García-Rodríguez, A; Martín-Jiménez, F; Carnero-Varo, M; Gómez-Gracia, E; Gómez-Aracena, J; Fernández-Crehuet, J

    1999-06-01

    To estimate the prevalence of flexible flat feet in the provincial population of 4- to 13-year-old schoolchildren and the incidence of treatments considered unnecessary. Province of Málaga, Spain. We examined and graded by severity a sample of 1181 pupils taken from a total population of 198 858 primary schoolchildren (CI: 95%; margin of error: 5%). The sample group was separated into three 2-year age groups: 4 and 5 years, 8 and 9 years, and 12 and 13 years. The plantar footprint was classified according to Denis1 into three grades of flat feet: grade 1 in which support of the lateral edge of the foot is half that of the metatarsal support; grade 2 in which the support of the central zone and forefoot are equal; and grade 3 in which the support in the central zone of the foot is greater than the width of the metatarsal support. The statistical analysis for the evaluation of the differences between the groups was performed with Student's t and chi2 tests as appropriate. The prevalence of flat feet was 2.7%. Of the 1181 children sampled, 168 children (14.2%) were receiving orthopedic treatment, but only 2.7% had diagnostic criteria of flat feet. When we inspected the sample, we found that a number of children were being treated for flat feet with boots and arch supports. Most of them did not have a flat plantar footprint according to the criteria that we used for this work. Furthermore, in the group of children that we diagnosed as having flat feet, only 28.1% were being treated. We found no significant differences between the number of children receiving orthopedic treatments and the presence or absence of a flat plantar footprint. Children who were overweight in the 4- and 5-year-old group showed an increased prevalence for flat feet as diagnosed by us. The data suggest that an excessive number of orthopedic treatments had been prescribed in the province. When extrapolated to the 1997 population of schoolchildren within the age groups studied the figures

  3. MOVING SCREW DISLOCATION IN CUBIC QUASICRYSTAL

    Institute of Scientific and Technical Information of China (English)

    ZHOU Wang-min; SONG Yu-hai

    2005-01-01

    The elasticity theory of the dislocation of cubic quasicrystals is developed.The governing equations of anti-plane elasticity dynamics problem of the quasicrystals were reduced to a solution of wave equations by introducing displacement functions,and the analytical expressions of displacements, stresses and energies induced by a moving screw dislocation in the cubic quasicrystalline and the velocity limit of the dislocation were obtained. These provide important information for studying the plastic deformation of the new solid material.

  4. 2-rational Cubic Spline Involving Tension Parameters

    Indian Academy of Sciences (India)

    M Shrivastava; J Joseph

    2000-08-01

    In the present paper, 1-piecewise rational cubic spline function involving tension parameters is considered which produces a monotonic interpolant to a given monotonic data set. It is observed that under certain conditions the interpolant preserves the convexity property of the data set. The existence and uniqueness of a 2-rational cubic spline interpolant are established. The error analysis of the spline interpolant is also given.

  5. Semisymmetric Cubic Graphs of Order 162

    Indian Academy of Sciences (India)

    Mehdi Alaeiyan; Hamid A Tavallaee; B N Onagh

    2010-02-01

    An undirected graph without isolated vertices is said to be semisymmetric if its full automorphism group acts transitively on its edge set but not on its vertex set. In this paper, we inquire the existence of connected semisymmetric cubic graphs of order 162. It is shown that for every odd prime , there exists a semisymmetric cubic graph of order 162 and its structure is explicitly specified by giving the corresponding voltage rules generating the covering projections.

  6. Cubical version of combinatorial differential forms

    DEFF Research Database (Denmark)

    Kock, Anders

    2010-01-01

    The theory of combinatorial differential forms is usually presented in simplicial terms. We present here a cubical version; it depends on the possibility of forming affine combinations of mutual neighbour points in a manifold, in the context of synthetic differential geometry.......The theory of combinatorial differential forms is usually presented in simplicial terms. We present here a cubical version; it depends on the possibility of forming affine combinations of mutual neighbour points in a manifold, in the context of synthetic differential geometry....

  7. Comparing Arc-shaped Feet and Rigid Ankles with Flat Feet and Compliant Ankles for a Dynamic Walker

    DEFF Research Database (Denmark)

    Kuhlemann, Ilyas; Matthias Braun, Jan; Wörgötter, Florentin

    2014-01-01

    walking robot RunBot, controlled by an reflexive neural network, uses only few sensors for generating its stable gait. The results show that at feet and compliant ankles extend RunBot's parameter range especially to more leaning back postures. They also allow the robot to stably walk over obstacles...

  8. Increase in efficiency of game by feet in modern rugby

    Directory of Open Access Journals (Sweden)

    Volodymyr Mucha

    2017-02-01

    Full Text Available Purpose: to define the importance of successful carrying out kicks of realization in rugby for the end result of the match. Material & Methods: the analysis of scientifically-methodical literature and the analysis of the developed results of matches in the rugby World Cups. Results: the reasons of the developed structure of effectiveness in rugby are described; the developed analysis of results of the final part of the World Cups in rugby of 2011 and 2015 is submitted. Conclusions: the significant place is taken not only by the brought attempts, and both their successful realization and other game elements by feet because of the high density of the final results and high level of preparedness of teams. The detailed analysis of results of the research demonstrates what not only realization is of great importance in points taking for the final result, but also all kicks by feet what their big percent at points taking testifies to.

  9. Cows-feet soup: a rare cause of recurrent trichobezoar.

    Science.gov (United States)

    Kiernan, Miles Finbar; Kamat, Sachin; Olagbaiye, Femi

    2012-01-01

    A 45-year-old Afro-Caribbean woman attended the emergency department with worsening dysphagia, abdominal distension, abdominal pain, shortness of breath and generalised weakness. She enjoyed preparing and eating cows-feet stew and preferred to cook the meat with the hair and skin intact. On admission she had a severe microcytic anaemia and was malnourished. Abdominal x-ray and CT revealed a large gastric bezoar. At gastrotomy a foul-smelling 2.42 kg mass of hair, leathery skin and altered food were evacuated from the lesser curvature of the stomach. She had undergone the same procedure 8 years earlier to remove a similar trichobezoar. Following psychiatric review it was deemed that the patient had no underlying psychiatric condition and had full insight into why her trichobezoar had re-occurred. She made a good postoperative recovery and stopped eating cows-feet stew.

  10. Incidence and management of ulcers in diabetic Charcot feet.

    Science.gov (United States)

    Larsen, K; Fabrin, J; Holstein, P E

    2001-09-01

    This study followed 115 patients with diabetes--who between them had 140 feet with Charcot's arthropathy--over six to 114 months (median: 48). A total of 43 patients (37%) developed ulcers in 53 feet. Their treatment was multifactorial. An offloading regimen was adopted, with the use of crutches and therapeutic sandals with soft, individually moulded insoles, followed by adjusted or bespoke shoes. Recalcitrant ulcers were treated with surgery in 16 patients (37%). Antibiotics were needed by 21 patients (49%). The incidence of ulceration was 17% per year. The median time interval between the acute component of Charcot's arthropathy and ulcer development was 36 months (range: 0-120 months). In seven patients, the ulcer developed during the acute phase. In 12 patients the ulcers were localised to the rockerbottom deformity in the mid-foot region, but in 31 patients other regions were affected. Dynamic footprint analysis was used to help adjust the offloading shoe/insole on the rockerbottom deformity. Such ulcers took twice as long to heal as other ulcers. Surgical treatment comprised: major amputation (two patients), arthrodesis for unstable ankle (three patients), toe amputations (seven patients), resection of the rockerbottom deformity (one patient) and other revisions (three patients). One patient died with an unhealed ulcer. There is a four-fold risk of ulcers in diabetic Charcot deformity compared with the overall risk of foot ulcers in diabetic feet. Healing was achieved in 40 patients (93%). The surgical intervention rate of 37% in ulcer cases in Charcot feet was low compared with the literature.

  11. Interpolation by two-dimensional cubic convolution

    Science.gov (United States)

    Shi, Jiazheng; Reichenbach, Stephen E.

    2003-08-01

    This paper presents results of image interpolation with an improved method for two-dimensional cubic convolution. Convolution with a piecewise cubic is one of the most popular methods for image reconstruction, but the traditional approach uses a separable two-dimensional convolution kernel that is based on a one-dimensional derivation. The traditional, separable method is sub-optimal for the usual case of non-separable images. The improved method in this paper implements the most general non-separable, two-dimensional, piecewise-cubic interpolator with constraints for symmetry, continuity, and smoothness. The improved method of two-dimensional cubic convolution has three parameters that can be tuned to yield maximal fidelity for specific scene ensembles characterized by autocorrelation or power-spectrum. This paper illustrates examples for several scene models (a circular disk of parametric size, a square pulse with parametric rotation, and a Markov random field with parametric spatial detail) and actual images -- presenting the optimal parameters and the resulting fidelity for each model. In these examples, improved two-dimensional cubic convolution is superior to several other popular small-kernel interpolation methods.

  12. Superhard BC(3) in cubic diamond structure.

    Science.gov (United States)

    Zhang, Miao; Liu, Hanyu; Li, Quan; Gao, Bo; Wang, Yanchao; Li, Hongdong; Chen, Changfeng; Ma, Yanming

    2015-01-01

    We solve the crystal structure of recently synthesized cubic BC(3) using an unbiased swarm structure search, which identifies a highly symmetric BC(3) phase in the cubic diamond structure (d-BC(3)) that contains a distinct B-B bonding network along the body diagonals of a large 64-atom unit cell. Simulated x-ray diffraction and Raman peaks of d-BC(3) are in excellent agreement with experimental data. Calculated stress-strain relations of d-BC(3) demonstrate its intrinsic superhard nature and reveal intriguing sequential bond-breaking modes that produce superior ductility and extended elasticity, which are unique among superhard solids. The present results establish the first boron carbide in the cubic diamond structure with remarkable properties, and these new findings also provide insights for exploring other covalent solids with complex bonding configurations.

  13. Cubical Cohomology Ring of 3D Photographs

    CERN Document Server

    Gonzalez-Diaz, Rocio; Medrano, Belen; 10.1002/ima.20271

    2011-01-01

    Cohomology and cohomology ring of three-dimensional (3D) objects are topological invariants that characterize holes and their relations. Cohomology ring has been traditionally computed on simplicial complexes. Nevertheless, cubical complexes deal directly with the voxels in 3D images, no additional triangulation is necessary, facilitating efficient algorithms for the computation of topological invariants in the image context. In this paper, we present formulas to directly compute the cohomology ring of 3D cubical complexes without making use of any additional triangulation. Starting from a cubical complex $Q$ that represents a 3D binary-valued digital picture whose foreground has one connected component, we compute first the cohomological information on the boundary of the object, $\\partial Q$ by an incremental technique; then, using a face reduction algorithm, we compute it on the whole object; finally, applying the mentioned formulas, the cohomology ring is computed from such information.

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  5. File list: Oth.Brs.20.AllAg.MCF-7-LTED [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Brs.20.AllAg.MCF-7-LTED hg19 TFs and others Breast MCF-7-LTED SRX180167,SRX0423...42 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Oth.Brs.20.AllAg.MCF-7-LTED.bed ...

  6. Purely cubic action for string field theory

    Science.gov (United States)

    Horowitz, G. T.; Lykken, J.; Rohm, R.; Strominger, A.

    1986-01-01

    It is shown that Witten's (1986) open-bosonic-string field-theory action and a closed-string analog can be written as a purely cubic interaction term. The conventional form of the action arises by expansion around particular solutions of the classical equations of motion. The explicit background dependence of the conventional action via the Becchi-Rouet-Stora-Tyutin operator is eliminated in the cubic formulation. A closed-form expression is found for the full nonlinear gauge-transformation law.

  7. Purely cubic action for string field theory

    Science.gov (United States)

    Horowitz, G. T.; Lykken, J.; Rohm, R.; Strominger, A.

    1986-01-01

    It is shown that Witten's (1986) open-bosonic-string field-theory action and a closed-string analog can be written as a purely cubic interaction term. The conventional form of the action arises by expansion around particular solutions of the classical equations of motion. The explicit background dependence of the conventional action via the Becchi-Rouet-Stora-Tyutin operator is eliminated in the cubic formulation. A closed-form expression is found for the full nonlinear gauge-transformation law.

  8. Design with the feet: walking methods and participatory design

    DEFF Research Database (Denmark)

    Kanstrup, Anne Marie; Bertelsen, Pernille; Madsen, Jacob Østergaard

    2014-01-01

    This paper presents an analysis of walking methods and their relation to participatory design (PD). The paper includes a study of walking methods found in the literature and an empirical study of transect walks in a PD project. From this analysis, we identify central attributes of, and challenges...... to, PD walks. Walking with people in the context of design is a natural activity for the participatory designer, who acknowledges the importance of immersion and relationships in design. However, the various intentions of walking approaches indicate an underacknowledged awareness of walking methods....... With this study, we take a step towards a methodological framework for "design with the feet" in PD....

  9. Feet swelling in a multistage ultraendurance triathlete: a case study

    Directory of Open Access Journals (Sweden)

    Knechtle B

    2015-10-01

    Full Text Available Beat Knechtle,1 Matthias Alexander Zingg,2 Patrizia Knechtle,1 Thomas Rosemann,2 Christoph Alexander Rüst2 1Gesundheitszentrum St Gallen, St Gallen, 2Institute of Primary Care, University of Zurich, Zurich, Switzerland Abstract: Recent studies investigating ultraendurance athletes showed an association between excessive fluid intake and swelling of the lower limbs such as the feet. To date, this association has been investigated in single-stage ultraendurance races, but not in multistage ultraendurance races. In this case study, we investigated a potential association between fluid intake and feet swelling in a multistage ultraendurance race such as a Deca Iron ultratriathlon with ten Ironman triathlons within 10 consecutive days. A 49-year-old well-experienced ultratriathlete competed in autumn 2013 in the Deca Iron ultratriathlon held in Lonata del Garda, Italy, and finished the race as winner within 129:33 hours:minutes. Changes in body mass (including body fat and lean body mass, foot volume, total body water, and laboratory measurements were assessed. Food and fluid intake during rest and competing were recorded, and energy and fluid turnovers were estimated. During the ten stages, the volume of the feet increased, percentage body fat decreased, creatinine and urea levels increased, hematocrit and hemoglobin values decreased, and plasma [Na+] remained unchanged. The increase in foot volume was significantly and positively related to fluid intake during the stages. The poststage volume of the foot was related to poststage total body water, poststage creatinine, and poststage urea. This case report shows that the volume of the foot increased during the ten stages, and the increase in volume was significantly and positively related to fluid intake during the stages. Furthermore, the poststage volume of the foot was related to poststage total body water, poststage creatinine, and poststage urea. The continuous feet swelling during the race was

  10. Fabrication of duck's feet collagen-silk hybrid biomaterial for tissue engineering.

    Science.gov (United States)

    Kim, Soo Hyeon; Park, Hae Sang; Lee, Ok Joo; Chao, Janet Ren; Park, Hyun Jung; Lee, Jung Min; Ju, Hyung Woo; Moon, Bo Mi; Park, Ye Ri; Song, Jeong Eun; Khang, Gilson; Park, Chan Hum

    2016-04-01

    Collagen constituting the extracellular matrix has been widely used as biocompatible material for human use. In this study, we have selected duck's feet for extracting collagen. A simple method not utilizing harsh chemical had been employed to extract collagen from duck's feet. We fabricated duck's feet collagen/silk hybrid scaffold for the purpose of modifying the degradation rate of duck's feet collagen. This study suggests that extracted collagen from duck's feet is biocompatible and resembles collagen extracted from porcine which is commercially used. Duck's feet collagen is also economically feasible and it could therefore be a good candidate as a tissue engineering material. Further, addition of silk to fabricate a duck's feet collagen/silk hybrid scaffold could enhance the biostability of duck's feet collagen scaffold. Duck's feet collagen/silk scaffold increased the cell viability compared to silk alone. Animal studies also showed that duck's feet collagen/silk scaffold was more biocompatible than silk alone and more biostable than duck's feet or porcine collagen alone. Additionally, the results revealed that duck's feet collagen/silk hybrid scaffold had high porosity, cell infiltration and proliferation. We suggest that duck's feet collagen/silk hybrid scaffold could be used as a dermal substitution for full thickness skin defects.

  11. DEFICIENT CUBIC SPLINES WITH AVERAGE SLOPE MATCHING

    Institute of Scientific and Technical Information of China (English)

    V. B. Das; A. Kumar

    2005-01-01

    We obtain a deficient cubic spline function which matches the functions with certain area matching over a greater mesh intervals, and also provides a greater flexibility in replacing area matching as interpolation. We also study their convergence properties to the interpolating functions.

  12. Counting rational points on cubic curves

    Institute of Scientific and Technical Information of China (English)

    HEATH-BROWN; Roger; TESTA; Damiano

    2010-01-01

    We prove upper bounds for the number of rational points on non-singular cubic curves defined over the rationals.The bounds are uniform in the curve and involve the rank of the corresponding Jacobian.The method used in the proof is a combination of the "determinant method" with an m-descent on the curve.

  13. CONSTRAINED RATIONAL CUBIC SPLINE AND ITS APPLICATION

    Institute of Scientific and Technical Information of China (English)

    Qi Duan; Huan-ling Zhang; Xiang Lai; Nan Xie; Fu-hua (Frank) Cheng

    2001-01-01

    In this paper, a kind of rational cubic interpolation functionwith linear denominator is constructed. The constrained interpolation with constraint on shape of the interpolating curves and on the second-order derivative of the interpolating function is studied by using this interpolation, and as the consequent result, the convex interpolation conditions have been derived.

  14. Anisotropy of a cubic ferromagnet at criticality

    Science.gov (United States)

    Kudlis, A.; Sokolov, A. I.

    2016-10-01

    Critical fluctuations change the effective anisotropy of cubic ferromagnet near the Curie point. If the crystal undergoes phase transition into orthorhombic phase and the initial anisotropy is not too strong, reduced anisotropy of nonlinear susceptibility acquires at Tc the universal value δ4*=2/v* 3 (u*+v*) where u* and v* are coordinates of the cubic fixed point on the flow diagram of renormalization group equations. In the paper, the critical value of the reduced anisotropy is estimated within the pseudo-ɛ expansion approach. The six-loop pseudo-ɛ expansions for u*, v*, and δ4* are derived for the arbitrary spin dimensionality n . For cubic crystals (n =3 ) higher-order coefficients of the pseudo-ɛ expansions obtained turn out to be so small that use of simple Padé approximants yields reliable numerical results. Padé resummation of the pseudo-ɛ series for u*, v*, and δ4* leads to the estimate δ4*=0.079 ±0.006 , indicating that detection of the anisotropic critical behavior of cubic ferromagnets in physical and computer experiments is certainly possible.

  15. Binomial Squares in Pure Cubic Number Fields

    CERN Document Server

    Lemmermeyer, Franz

    2011-01-01

    Let K = Q(\\omega) with \\omega^3 = m be a pure cubic number field. We show that the elements\\alpha \\in K^\\times whose squares have the form a - \\omega form a group isomorphic to the group of rational points on the elliptic curve E_m: y^2= x^3 - m.

  16. The cactus rank of cubic forms

    CERN Document Server

    Bernardi, Alessandra

    2011-01-01

    We prove that the smallest degree of an apolar 0-dimensional scheme to a general cubic form in $n+1$ variables is at most $2n+2$, when $n\\geq 8$, and therefore smaller than the rank of the form. When n=8 we show that the bound is sharp, i.e. the smallest degree of an apolar subscheme is 18.

  17. Insulin stimulated MCF7 breast cancer cells: Proteome dataset.

    Science.gov (United States)

    Sarvaiya, Hetal A; Lazar, Iulia M

    2016-12-01

    The proteome data provided in this article were acquired from MCF7 breast cancer cells stimulated with insulin, and were generated by using a 2D-SCX (strong cation exchange)/RPLC (reversed phase liquid chromatography) separation protocol followed by tandem mass spectrometry (MS) detection. To facilitate data re-processing by more advanced search engines and the extraction of additional information from already existing files, both raw and processed data are provided. The sample preparation, data acquisition and processing protocols are described in detail. The raw data relate to work published in "Proteome profile of the MCF7 cancer cell line: a mass spectrometric evaluation" (Sarvaiya et al., 2006) [1] and are made available through the PRIDE (PRoteomics IDEntifications)/ProteomeXchange public repository with identifier PRIDE: PXD004051 ("2016 update of the PRIDE database and tools" (Vizcaino et al., 2016) [2]).

  18. Insulin stimulated MCF7 breast cancer cells: Proteome dataset

    Directory of Open Access Journals (Sweden)

    Hetal A. Sarvaiya

    2016-12-01

    Full Text Available The proteome data provided in this article were acquired from MCF7 breast cancer cells stimulated with insulin, and were generated by using a 2D-SCX (strong cation exchange/RPLC (reversed phase liquid chromatography separation protocol followed by tandem mass spectrometry (MS detection. To facilitate data re-processing by more advanced search engines and the extraction of additional information from already existing files, both raw and processed data are provided. The sample preparation, data acquisition and processing protocols are described in detail. The raw data relate to work published in “Proteome profile of the MCF7 cancer cell line: a mass spectrometric evaluation” (Sarvaiya et al., 2006 [1] and are made available through the PRIDE (PRoteomics IDEntifications/ProteomeXchange public repository with identifier PRIDE: PXD004051 (“2016 update of the PRIDE database and tools” (Vizcaino et al., 2016 [2].

  19. Turkish propolis supresses MCF-7 cell death induced by homocysteine.

    Science.gov (United States)

    Tartik, Musa; Darendelioglu, Ekrem; Aykutoglu, Gurkan; Baydas, Giyasettin

    2016-08-01

    Elevated plasma homocysteine (Hcy) level is a most important risk factor for various vascular diseases including coronary, cerebral and peripheral arterial and venous thrombosis. Propolis is produced by honeybee from various oils, pollens and wax materials. Therefore, it has various biological properties including antioxidant, antitumor and antimicrobial activities. This study investigated the effects of propolis and Hcy on apoptosis in cancer cells. According to our findings, Hcy induced apoptosis in human breast adenocarcinoma (MCF-7) cells by regulating numerous genes and proteins involved in the apoptotic signal transduction pathway. In contrast, treatment with propolis inhibited caspase- 3 and -9 induced by Hcy in MCF-7 cells. It can be concluded that Hcy may augment the activity of anticancer agents that induce excessive reactive oxygen species (ROS) generation and apoptosis in their target cells. In contrast to the previous studies herein we found that propolis in low doses protected cancer cells inhibiting cellular apoptosis mediated by intracellular ROS-dependent mitochondrial pathway.

  20. The molecular mechanism and synergistic effect of anti-bFGF monoclonal antibody combined Taxol in suppressing MCF-7 and MCF-7/Taxol%bFGF单抗联合紫杉醇抑制MCF-7及MCF-7紫杉醇耐药株(MCF-7/Taxol)增效作用的分子机制

    Institute of Scientific and Technical Information of China (English)

    邵晨晨; 黄建芳; 谈思怡; 刘诗琴; 向军俭

    2016-01-01

    目的 研究bFGF单抗联合紫杉醇(Taxol)抑制MCF-7细胞增殖、诱导细胞凋亡的分子机制;探讨bFGF单抗联合Taxol对耐药株MCF-7/Taxol的增效作用及机制.方法 CCK-8法检测bFGF单抗联合Taxol对MCF-7及MCF-7/Taxol增殖抑制率;流式细胞术检测二者联合对MCF-7、MCF-7/Taxol的凋亡作用;Western blot检测MCF-7及MCF-7/Taxol相关信号通路蛋白的表达变化.结果 CCK-8法检测结果显示bFGF单抗联合Taxol作用MCF-7、MCF-7/Taxol后对其增殖抑制率分别提高了13.40%~36.50%、9.56%~26.87%,联合能加强对细胞抑制作用.流式细胞术结果显示bFGF单抗联合Taxol作用MCF-7、MCF-7/Taxol后PI、FITC双阳性率分别提高了17.10% ~23.20%、22.00% ~22.70%,表明联合能加强对凋亡作用.Western blot结果显示MCF-7、MCF-7/Taxol中MabD9+ Taxol组能明显下调Raf-1、p-Erk、p-STAT3、Bcl-2、Caspase3,并上调p-JNK、Bax、cleavedCaspase3、cleaved PARP,其中Raf-1在MCF-7/Taxol中表达量较MCF-7明显下降.结论 本研究揭示了bFGF单抗联合Taxol抑制MCF-7的如下机制:加强对Erk/MAPK通路的抑制,并加强上调p-JNK,下调p-STAT3的表达量,引起Bcl-2表达量下调,Bax表达上调,Caspase3、cleaved Caspase3、cleaved PARP表达变化引起细胞凋亡.且耐药株除具类似的抑制机制外,其Raf-1下调更加明显.

  1. Friction force reduction triggers feet grooming behaviour in beetles.

    Science.gov (United States)

    Hosoda, Naoe; Gorb, Stanislav N

    2011-06-01

    In insects, cleaning (grooming) of tarsal attachment devices is essential for maintaining their adhesive ability, necessary for walking on a complex terrain of plant surfaces. How insects obtain information on the degree of contamination of their feet has remained, until recently, unclear. We carried out friction force measurements on walking beetles Gastrophysa viridula (Coleoptera, Chrysomelidae) and counted grooming occurrence on stiff polymer substrata with different degrees of nanoroughness (root mean square: 28-288 nm). Since nanoscopically, rough surfaces strongly reduced friction and adhesion without contaminating feet, we were able to demonstrate, for the first time to our knowledge, that friction force between tarsal attachment pads and the substrate provides an insect with information on the degree of contamination of its attachment structures. We have shown that foot grooming occurrence correlates not only with the degree of contamination but also with the decrease of friction force. This result indicates that insects obtain information about the degree of contamination, not statically but rather dynamically and, presumably, use mechanoreceptors monitoring either tensile/compressive forces in the cuticle or tensile forces between leg segments.

  2. Ytterbium: Transition at High Pressure from Face-Centered Cubic to Body-Centered Cubic Structure.

    Science.gov (United States)

    Hall, H T; Barnett, J D; Merrill, L

    1963-01-11

    Pressure of 40,000 atmospheres at 25 degrees C induces a phase transformation in ytterbium metal; the face-centered cubic structure changes to body-centered cubic. The radius of the atom changes from 1.82 to 1.75 A. At the same time the atom's volume decreases by 11 percent and the volume, observed macroscopically, decreases 3.2 percent.

  3. Cytotoxicity and Genotoxicity Assessment of Sandalwood Essential Oil in Human Breast Cell Lines MCF-7 and MCF-10A

    Directory of Open Access Journals (Sweden)

    Carmen Ortiz

    2016-01-01

    Full Text Available Sandalwood essential oil (SEO is extracted from Santalum trees. Although α-santalol, a main constituent of SEO, has been studied as a chemopreventive agent, the genotoxic activity of the whole oil in human breast cell lines is still unknown. The main objective of this study was to assess the cytotoxic and genotoxic effects of SEO in breast adenocarcinoma (MCF-7 and nontumorigenic breast epithelial (MCF-10A cells. Proteins associated with SEO genotoxicity were identified using a proteomics approach. Commercially available, high-purity, GC/MS characterized SEO was used to perform the experiments. The main constituents reported in the oil were (Z-α-santalol (25.34%, (Z-nuciferol (18.34%, (E-β-santalol (10.97%, and (E-nuciferol (10.46%. Upon exposure to SEO (2–8 μg/mL for 24 hours, cell proliferation was determined by the MTT assay. Alkaline and neutral comet assays were used to assess genotoxicity. SEO exposure induced single- and double-strand breaks selectively in the DNA of MCF-7 cells. Quantitative LC/MS-based proteomics allowed identification of candidate proteins involved in this response: Ku70 (p=1.37E-2, Ku80 (p=5.8E-3, EPHX1 (p=3.3E-3, and 14-3-3ζ (p=4.0E-4. These results provide the first evidence that SEO is genotoxic and capable of inducing DNA single- and double-strand breaks in MCF-7 cells.

  4. Stationary Apparatus Would Apply Forces of Walking to Feet

    Science.gov (United States)

    Hauss, Jessica; Wood, John; Budinoff, Jason; Correia, Michael; Albrecht, Rudolf

    2006-01-01

    A proposed apparatus would apply controlled cyclic forces to both feet for the purpose of preventing the loss of bone density in a human subject whose bones are not subjected daily to the mechanical loads of normal activity in normal Earth gravitation. The apparatus was conceived for use by astronauts on long missions in outer space; it could also be used by bedridden patients on Earth, including patients too weak to generate the necessary forces by their own efforts. The apparatus (see figure) would be a modified version of a bicycle-like exercise machine, called the cycle ergometer with vibration isolation system (CEVIS), now aboard the International Space Station. Attached to each CEVIS pedal would be a computer-controlled stress/ vibration exciter connected to the heel portion of a special-purpose pedal. The user would wear custom shoes that would amount to standard bicycle shoes equipped with cleats for secure attachment of the balls of the feet to the special- purpose pedals. If possible, prior to use of the apparatus, the human subject would wear a portable network of recording accelerometers, while walking, jogging, and running. The information thus gathered would be fed to the computer, wherein it would be used to make the exciters apply forces and vibrations closely approximating the forces and vibrations experienced by that individual during normal exercise. It is anticipated that like the forces applied to bones during natural exercise, these artificial forces would stimulate the production of osteoblasts (bone-forming cells), as needed to prevent or retard loss of bone mass. In addition to helping to prevent deterioration of bones, the apparatus could be used in treating a person already suffering from osteoporosis. For this purpose, the magnitude of the applied forces could be reduced, if necessary, to a level at which weak hip and leg bones would still be stimulated to produce osteoblasts without exposing them to the full stresses of walking and

  5. Face-Centered-Cubic Nanostructured Polymer Foams

    Science.gov (United States)

    Cui, C.; Baughman, R. H.; Liu, L. M.; Zakhidov, A. A.; Khayrullin, I. I.

    1998-03-01

    Beautifully iridescent polymer foams having Fm-3m cubic symmetry and periodicities on the scale of the wavelength of light have been synthesized by the templating of porous synthetic opals. These fabrication processes involve the filling of porous SiO2 opals (with typical cubic lattice parameters of 250 nm) with either polymers or polymer precursors, polymerization of the precursors if necessary, and removal of the fcc array of SiO2 balls to provide an all-polymer structure. The structures of these foams are similar to periodic minimal surfaces, although the Gaussian curvature can have both positive and negative values. Depending upon whether the internal surfaces of the opal are polymer filled or polymer coated, the polymer replica has either one or two sets of independent channels. We fill these channels with semiconductors, metals, or superconductors to provide electronic and optical materials with novel properties dependent on the nanoscale periodicity.

  6. Cubic Polynomials with Rational Roots and Critical Points

    Science.gov (United States)

    Gupta, Shiv K.; Szymanski, Waclaw

    2010-01-01

    If you want your students to graph a cubic polynomial, it is best to give them one with rational roots and critical points. In this paper, we describe completely all such cubics and explain how to generate them.

  7. Use of Pom Pons to Illustrate Cubic Crystal Structures.

    Science.gov (United States)

    Cady, Susan G.

    1997-01-01

    Describes a method that uses olefin pom pons to illustrate cubic crystal structure. Facilitates hands-on examination of different packing arrangements such as hexagonal close-packed and cubic close-packed structures. (JRH)

  8. Shape preserving rational bi-cubic function

    Directory of Open Access Journals (Sweden)

    Malik Zawwar Hussain

    2012-11-01

    Full Text Available The study is dedicated to the development of shape preserving interpolation scheme for monotone and convex data. A rational bi-cubic function with parameters is used for interpolation. To preserve the shape of monotone and convex data, the simple data dependent constraints are developed on these parameters in each rectangular patch. The developed scheme of this paper is confined, cheap to run and produce smooth surfaces.

  9. Cubic Lienard Equations with Quadratic Damping (Ⅱ)

    Institute of Scientific and Technical Information of China (English)

    Yu-quan Wang; Zhu-jun Jing

    2002-01-01

    Applying Hopf bifurcation theory and qualitative theory, we show that the general cubic Lienard equations with quadratic damping have at most three limit cycles. This implies that the guess in which the system has at most two limit cycles is false. We give the sufficient conditions for the system has at most three limit cycles or two limit cycles. We present two examples with three limit cycles or two limit cycles by using numerical simulation.

  10. Energy storage and release of prosthetic feet. Part 2: subjective ratings of 2 energy storing and 2 conventional feet, user choice of foot and deciding factor

    NARCIS (Netherlands)

    Postema, K.; Hermens, Hermanus J.; de Vries, J.; de Vries, J.; Koopman, Hubertus F.J.M.; Eisma, W.H.

    1997-01-01

    This paper is the second part of a study on biomechanical and functional properties of prosthetic feet. The first part dealt with a biomechanical analysis related to user benefits. This part deals with subjective ratings and deciding factors for trans-tibial amputees using 2 energy storing feet (ESF

  11. Energy storage and release of prosthetic feet Part 2: Subjective ratings of 2 energy storing and 2 conventional feet, user choice of foot and deciding factor

    NARCIS (Netherlands)

    Postema, K.; Hermens, H.J.; Vries, de J.; Koopman, H.F.J.M.; Eisma, W.H.

    1997-01-01

    This paper is the second part of a study on biomechanical and functional properties of prosthetic feet. The first part dealt with a biomechanical analysis related to user benefits. This part deals with subjective ratings and deciding factors for trans-tibial amputees using 2 energy storing feet (ESF

  12. Local atomic structure in cubic stabilized zirconia

    Energy Technology Data Exchange (ETDEWEB)

    Villella, P.; Conradson, S. D.; Espinosa-Faller, F. J.; Foltyn, S. R.; Sickafus, K. E.; Valdez, J. A.; Degueldre, C. A.

    2001-09-01

    X-ray-absorption fine structure measurements have been used to elucidate the local atomic structure of quaternary Zr, Y, Er, Ce/U cubic stabilized zirconia. These compounds display more complicated local environments than those reported for simpler binary systems. While the shortest cation-O distances are similar to those found in the binary cubic stabilized compounds, responding to the different sizes of the cations, we have identified large distortions in the first-shell oxygen distribution involving long, 2.8--3.2 {angstrom} cation-O distances that are similar to those found in the amorphous phase of zirconium. The cation-cation distributions are also found to be quite complicated (non-Gaussian) and element specific. The U-near neighbor distances are expanded relative to the Ce ions for which it substitutes, consistent with the larger size of the actinide, and the U-cation distribution is also more complicated. In terms of the effects of this substitution on the other cation sites, the local environment around Y is altered while the Zr and Er local environments remain unchanged. These results point out the importance of collective and correlated interactions between the different pairs of cations and the host lattice that are mediated by the local strain fields generated by the different cations. The presence of pair-specific couplings has not been commonly included in previous analyses and may have implications for the stabilization mechanisms of cubic zirconia.

  13. The special symplectic structure of binary cubics

    CERN Document Server

    Slupinski, Marcus

    2009-01-01

    Let $k$ be a field of characteristic not 2 or 3. Let $V$ be the $k$-space of binary cubic polynomials. The natural symplectic structure on $k^2$ promotes to a symplectic structure $\\omega$ on $V$ and from the natural symplectic action of $\\textrm{Sl}(2,k)$ one obtains the symplectic module $(V,\\omega)$. We give a complete analysis of this symplectic module from the point of view of the associated moment map, its norm square $Q$ (essentially the classical discriminant) and the symplectic gradient of $Q$. Among the results are a symplectic derivation of the Cardano-Tartaglia formulas for the roots of a cubic, detailed parameters for all $\\textrm{Sl}(2,k)$ and $\\textrm{Gl}(2,k)$-orbits, in particular identifying a group structure on the set of $\\textrm{Sl}(2,k)$-orbits of fixed nonzero discriminant, and a purely symplectic generalization of the classical Eisenstein syzygy for the covariants of a binary cubic. Such fine symplectic analysis is due to the special symplectic nature inherited from the ambient excepti...

  14. Method of synthesizing cubic system boron nitride

    Energy Technology Data Exchange (ETDEWEB)

    Yuzu, S.; Sumiya, H.; Degawa, J.

    1987-10-13

    A method is described for synthetically growing cubic system boron nitride crystals by using boron nitride sources, solvents for dissolving the boron nitride sources, and seed crystals under conditions of ultra-high pressure and high temperature for maintaining the cubic system boron nitride stable. The method comprises the following steps: preparing a synthesizing vessel having at least two chambers, arrayed in order in the synthesizing vessel so as to be heated according to a temperature gradient; placing the solvents having different eutectic temperatures in each chamber with respect to the boron nitride sources according to the temperature gradient; placing the boron nitride source in contact with a portion of each of the solvents heated at a relatively higher temperature and placing at least a seed crystal in a portion of each of the solvents heated at a relatively lower temperature; and growing at least one cubic system boron nitride crystal in each of the solvents in the chambers by heating the synthesizing vessel for establishing the temperature gradient while maintaining conditions of ultra-high pressure and high temperature.

  15. Elevation of cysteine consumption in tamoxifen-resistant MCF-7 cells.

    Science.gov (United States)

    Ryu, Chang Seon; Kwak, Hui Chan; Lee, Ji-Yoon; Oh, Soo Jin; Phuong, Nguyen Thi Thuy; Kang, Keon Wook; Kim, Sang Kyum

    2013-01-15

    Tamoxifen (TAM) resistance is a main cause of therapeutic failure in breast cancers. Although methionine dependency is a phenotypic characteristic of tumor cells, the role of sulfur amino acid metabolism in chemotherapy resistance remains to be elucidated. This study compared metabolite profiles of sulfur amino acid metabolism from methionine to taurine or glutathione (GSH) between normal MCF-7 and TAM-resistant MCF-7 (TAMR-MCF-7) cells. TAMR-MCF-7 cells showed elevated levels and activities of enzymes involved in both transsulfuration from methionine to cysteine and metabolism of cysteine to GSH and taurine. Cysteine concentrations in TAMR-MCF-7 cells and medium conditioned by cell culture for 42h were markedly decreased, while GSH, hypotaurine, and taurine concentrations in the medium were increased. These results show that TAMR-MCF-7 cells display enhanced cysteine utilization. The addition of propargylglycine, a specific cystathionine γ-lyase inhibitor, and buthionine sulfoximine, a specific γ-glutamylcysteine ligase inhibitor, to TAMR-MCF-7 cells, but not to MCF-7 cells, resulted in cytotoxicity after sulfur amino acid deprivation. These results suggest that cell viability of TAMR-MCF-7 cells is affected by inhibition of sulfur amino acid metabolism, particularly cysteine synthesis from homocysteine and GSH synthesis from cysteine. Additionally, the S-adenosylmethionine/S-adenosylhomocysteine ratio, an index of transmethylation potential, in TAMR-MCF-7 cells increased to ~3.6-fold relative to that in MCF-7 cells, a finding that may result from upregulation of methionine adenosyltransferase IIa and S-adenosylhomocysteine hydrolase. In conclusion, this study suggests that TAMR-MCF-7 cells display enhanced cysteine utilization for synthesis of GSH and taurine, and are sensitive to inhibition of cysteine metabolism.

  16. Compliant Biped Walking on Uneven Terrain with Point Feet

    Directory of Open Access Journals (Sweden)

    Wenqi Hou

    2016-03-01

    Full Text Available In this paper, we aim to realize compliant biped walking on uneven terrain with point feet. A control system is designed for a 5-link planar biped walker. According to the role that each leg plays, the control system is decomposed into two parts: the swing leg control and the support leg control. The trajectory of the swing foot is generated in realtime to regulate the walking speed. By considering the reaction torque of the swing leg’s hip joint as disturbance, a sliding model controller is implemented at the support leg’s hip joint to control the torso’s posture angle. In order to make sure the landing foot does not rebound after impact, the vertical contact force control is set as the internal loop of the hip’s height control. In simulation, the control system is tested on a virtual 5-link planar biped walker in Matlab. Finally, stable biped walking is realized on uneven terrain with roughness up to 2cm.

  17. Non-contrast MRI perfusion angiosome in diabetic feet

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Jie [Cardiovascular Imaging Lab, Mallinckrodt Institute of Radiology, St. Louis, MO (United States); Hastings, Mary K.; Mueller, Michael J. [Washington University School of Medicine, The Program in Physical Therapy, St. Louis, MO (United States); Muccigross, David; Hildebolt, Charles F. [Washington University School of Medicine, Mallinckrodt Institute of Radiology, St. Louis, MO (United States); Fan, Zhaoyang [Cedars-Sinai Medical Center, Biomedical Imaging Research Institute, Los Angeles, CA (United States); Gao, Fabao [West China Hospital, Sichuan University, Department of Radiology, Chengdu (China); Curci, John [Washington University School of Medicine, The Department of Surgery, St. Louis, MO (United States)

    2015-01-15

    The purpose of this study is to develop a non-contrast magnetic resonance imaging (MRI) approach to evaluate skeletal muscle perfusion in the diabetic foot based on the concept of angiosomes of the foot. Five healthy volunteers and five participants with diabetes (HbA1c = 7.2 ± 1.8 %) without a history of peripheral artery disease were examined. The non-contrast perfusion measurements were performed during a toe flexion challenge. Absolute perfusion maps were created and two regions (medial and lateral) on the maps were segmented based on angiosomes. Regional difference in the perfusion of foot muscle was readily visualized in the MRI perfusion angiosomes during the challenge. In the participants with diabetes, the perfusion during toe flexion challenge was significantly lower than in healthy volunteers (P < 0.01). The average perfusion for the medial plantar region of the right foot was lower in subjects with diabetes (38 ± 9 ml/min/100 g) than in healthy subjects (93 ± 33 ml/min/100 g). Non-contrast MRI perfusion angiosome maps demonstrate the feasibility of determining regional perfusion in foot muscles during toe challenge and may facilitate evaluation of muscle perfusion in diabetic feet. (orig.)

  18. Accessory bones of the feet: Radiological analysis of frequency

    Directory of Open Access Journals (Sweden)

    Vasiljević Vladica

    2010-01-01

    Full Text Available Background/Aim. Accessory bones are most commonly found on the feet and they represent an anatomic variant. They occur when there is a failure in the formation of a unique bone from separated centre of ossification. The aim of this study was to establish their frequency and medical significance. Methods. Anteroposterior and lateral foot radiography was performed in 270 patients aged of 20-80 years with a history of trauma (180 and rheumatology disease (90. The presence and distribution of accessory bones was analysed in relation to the total number of patients and their gender. The results are expressed in numeric values and in terms of percentage. Results. Accessory bones were identified in 62 (22.96% patients: 29 (10.74% of them were found in female patients and 33 (12.22% in males. The most common accessory bones were as follows: os tibiale externum 50%, os peroneum 29.03%, ostrigonum 11.29%, os vaselianum 9.68%. Conclusion. Accessory bones found in 23% of patients with trauma and some of rheumatological diseases. Their significance is demonstrated in the differential diagnosis among degenerative diseases, avulsion fractures, muscle and tendon trauma and other types of injuries which can cause painful affection of the foot, as well as in forensic practice.

  19. Cherenkov and Scintillation Properties of Cubic Zirconium

    Science.gov (United States)

    Christl, M.J.; Adams, J.H.; Parnell, T.A.; Kuznetsov, E.N.

    2008-01-01

    Cubic zirconium (CZ) is a high index of refraction (n =2.17) material that we have investigated for Cherenkov counter applications. Laboratory and proton accelerator tests of an 18cc sample of CZ show that the expected fast Cherenkov response is accompanied by a longer scintillation component that can be separated by pulse shaping. This presents the possibility of novel particle spectrometers which exploits both properties of CZ. Other high index materials being examined for Cherenkov applications will be discussed. Results from laboratory tests and an accelerator exposure will be presented and a potential application in solar energetic particle instruments will be discussed

  20. Tachyon Vacuum in Cubic Superstring Field Theory

    CERN Document Server

    Erler, Theodore

    2008-01-01

    In this paper we give an exact analytic solution for tachyon condensation in the modified (picture 0) cubic superstring field theory. We prove the absence of cohomology and, crucially, reproduce the correct value for the D-brane tension. The solution is surprising for two reasons: First, the existence of a tachyon vacuum in this theory has not been definitively established in the level expansion. Second, the solution {\\it vanishes} in the GSO$(-)$ sector, implying a ``tachyon vacuum'' solution exists even for a {\\it BPS} D-brane.

  1. Generalized fairing algorithm of parametric cubic splines

    Institute of Scientific and Technical Information of China (English)

    WANG Yuan-jun; CAO Yuan

    2006-01-01

    Kjellander has reported an algorithm for fairing uniform parametric cubic splines. Poliakoff extended Kjellander's algorithm to non-uniform case. However, they merely changed the bad point's position, and neglected the smoothing of tangent at bad point. In this paper, we present a fairing algorithm that both changed point's position and its corresponding tangent vector. The new algorithm possesses the minimum property of energy. We also proved Poliakoff's fairing algorithm is a deduction of our fairing algorithm. Several fairing examples are given in this paper.

  2. Fractal Symmetries: Ungauging the Cubic Code

    CERN Document Server

    Williamson, Dominic J

    2016-01-01

    Gauging is a ubiquitous tool in many-body physics. It allows one to construct highly entangled topological phases of matter from relatively simple phases and to relate certain characteristics of the two. Here we develop a gauging procedure for general submanifold symmetries of Pauli Hamiltonians, including symmetries of fractal type. We show a relation between the pre- and post- gauging models and use this to construct short range entangled phases with fractal like symmetries, one of which is mapped to the cubic code by the gauging.

  3. The Exact Limit of Some Cubic Towers

    DEFF Research Database (Denmark)

    Anbar Meidl, Nurdagül; Beelen, Peter; Nguyen, Nhut

    2016-01-01

    Recently, a new explicit tower of function fields was introduced by Bassa, Beelen, Garcia and Stichtenoth (BBGS). This resulted in currently the best known lower bound for Ihara’s constant in the case of non-prime finite fields. In particular over cubic fields, the tower’s limit is at least as good...... as Zink’s bound; i.e. λ(BBGS/Fq3 ) ≥ 2(q2 - 1)/(q + 2). In this paper, the exact value of λ(BBGS/Fq3 ) is computed. We also settle a question stated by Ihara....

  4. Competing structural instabilities in cubic perovskites

    CERN Document Server

    Vanderbilt, D

    1994-01-01

    We study the antiferrodistortive instability and its interaction with ferroelectricity in cubic perovskite compounds. Our first-principles calculations show that coexistence of both instabilities is very common. We develop a first-principles scheme to study the thermodynamics of these compounds when both instabilities are present, and apply it to SrTiO$_3$. We find that increased pressure enhances the antiferrodistortive instability while suppressing the ferroelectric one. Moreover, the presence of one instability tends to suppress the other. A very rich $P$--$T$ phase diagram results.

  5. Rheological properties of Cubic colloidal suspensions

    Science.gov (United States)

    Boromand, Arman; Maia, Joao

    2016-11-01

    Colloidal and non-colloidal suspensions are ubiquitous in many industrial application. There are numerous studies on these systems to understand and relate their complex rheological properties to their microstructural evolution under deformation. Although most of the experimental and simulation studies are centered on spherical particles, in most of the industrial applications the geometry of the colloidal particles deviate from the simple hard sphere and more complex geometries exist. Recent advances in microfabrication paved the way to fabricate colloidal particles with complex geometries for applications in different areas such as drug delivery where the fundamental understanding of their dynamics has remained unexplored. In this study, using dissipative particle dynamics, we investigate the rheological properties of cubic (superball) particles which are modeled as the cluster of core-modified DPD particles. Explicit representation of solvent particles in the DPD scheme will conserve the full hydrodynamic interactions between colloidal particles. Rheological properties of these cubic suspensions are investigated in the dilute and semi-dilute regimes. The Einstein and Huggins coefficients for these particles with different superball exponent will be calculate which represent the effect of single particle's geometry and multibody interactions on viscosity, respectively. The response of these suspensions is investigated under simple shear and oscillatory shear where it is shown that under oscillation these particles tend to form crystalline structure giving rise to stronger shear-thinning behavior recently measured experimentally.

  6. Effects of solanine on microtubules system of human breast cancer MCF-7 cells%龙葵碱对乳腺癌MCF-7细胞微管系统的影响

    Institute of Scientific and Technical Information of China (English)

    季宇彬; 刘家源; 高世勇

    2012-01-01

    Objective To investigate the effects of solanine on tnicrotubular system in MCF-7 cell line. Methods Proliferation inhibition of MCF-7 cell line was evaluated by MTT assay. Cell cycle of MCF-7 cells was analyzed and the changes of a-tubulin protein and microtubule-associated protein 2 (MAP-2) protein were detected by flow cytometry. Results The IC50 of MCF-7 cells was 22.08 ng/mL. Solanine could induce MCF-7 cells arrested in S phaseand increase the levels of a-tubulin and MAP-2 in MCF-7 cell line. Conclusion Solanine could inhibit the MCF-7 cell proliferation by increasing a-tubulin and MAP-2 expression and inducing MCF-7 cells arrested in S phase.%目的 研究龙葵碱对乳腺癌MCF-7细胞微管系统的影响.方法 MTT法检测龙葵碱对人乳腺癌MCF-7细胞增殖的抑制作用,流式细胞仪分析龙葵碱对MCF-7细胞周期的影响以及细胞内α-微管蛋白及微管相关蛋白(MAP-2)的变化.结果 龙葵碱对MCF-7细胞的IC50为22.08 μg/mL,能够将MCF-7细胞阻滞于S期;能够增加MCF-7细胞内α-微管蛋白和MAP-2的量.结论 龙葵碱通过升高MCF-7细胞内的微管蛋白及MAP-2的表达,将MCF-7细胞阻滞于S期,从而抑制乳腺癌MCF-7细胞的生长.

  7. ANTIPROLIFERATIVE EFFECT ON BREAST CANCER (MCF7) OF MORINGA OLEIFERA SEED EXTRACTS.

    Science.gov (United States)

    Adebayo, Ismail Abiola; Arsad, Hasni; Samian, Mohd Razip

    2017-01-01

    Moringa oleifera belongs to plant family, Moringaceae and popularly called "wonderful tree", for it is used traditionally to cure many diseases including cancer in Africa and Asia, however, there is limited knowledge on cytotoxic activity of Moringa oleifera seeds on MCF7 breast cancer cell. The present study evaluated antiproliferative effect on MCF7 of the seed. Seeds of Moringa oleifera were grinded to powder and its phytochemicals were extracted using water and 80% ethanol solvents, part of the ethanolic extract were sequentially partitioned to fractions with four solvents (hexane, dichloromethane, chloroform, and n-butanol). Antiproliferative effects on MCF7 of the samples were determined. Finally, potent samples that significantly inhibited MCF7 growth were tested on MCF 10A. Crude water extract, hexane and dichloromethane fractions of the seeds inhibited the proliferation of MCF7 with the following IC50 values 280 μg/ml, 130 μg/ml and 26 μg/ml respectively, however, of the 3 samples, only hexane fraction had minimal cytotoxic effect on MCF 10A (IC50 > 400μg/ml). Moringa oleifera seed has antiproliferative effect on MCF7.

  8. All unitary cubic curvature gravities in D dimensions

    Energy Technology Data Exchange (ETDEWEB)

    Sisman, Tahsin Cagri; Guellue, Ibrahim; Tekin, Bayram, E-mail: sisman@metu.edu.tr, E-mail: e075555@metu.edu.tr, E-mail: btekin@metu.edu.tr [Department of Physics, Middle East Technical University, 06531 Ankara (Turkey)

    2011-10-07

    We construct all the unitary cubic curvature gravity theories built on the contractions of the Riemann tensor in D-dimensional (anti)-de Sitter spacetimes. Our construction is based on finding the equivalent quadratic action for the general cubic curvature theory and imposing ghost and tachyon freedom, which greatly simplifies the highly complicated problem of finding the propagator of cubic curvature theories in constant curvature backgrounds. To carry out the procedure we have also classified all the unitary quadratic models. We use our general results to study the recently found cubic curvature theories using different techniques and the string generated cubic curvature gravity model. We also study the scattering in critical gravity and give its cubic curvature extensions.

  9. Leptin regulates energy metabolism in MCF-7 breast cancer cells.

    Science.gov (United States)

    Blanquer-Rosselló, Maria del Mar; Oliver, Jordi; Sastre-Serra, Jorge; Valle, Adamo; Roca, Pilar

    2016-03-01

    Obesity is known to be a poorer prognosis factor for breast cancer in postmenopausal women. Among the diverse endocrine factors associated to obesity, leptin has received special attention since it promotes breast cancer cell growth and invasiveness, processes which force cells to adapt their metabolism to satisfy the increased demands of energy and biosynthetic intermediates. Taking this into account, our aim was to explore the effects of leptin in the metabolism of MCF-7 breast cancer cells. Polarographic analysis revealed that leptin increased oxygen consumption rate and cellular ATP levels were more dependent on mitochondrial oxidative metabolism in leptin-treated cells compared to the more glycolytic control cells. Experiments with selective inhibitors of glycolysis (2-DG), fatty acid oxidation (etomoxir) or aminoacid deprivation showed that ATP levels were more reliant on fatty acid oxidation. In agreement, levels of key proteins involved in lipid catabolism (FAT/CD36, CPT1, PPARα) and phosphorylation of the energy sensor AMPK were increased by leptin. Regarding glucose, cellular uptake was not affected by leptin, but lactate release was deeply repressed. Analysis of pyruvate dehydrogenase (PDH), lactate dehydrogenase (LDH) and pyruvate carboxylase (PC) together with the pentose-phosphate pathway enzyme glucose-6 phosphate dehydrogenase (G6PDH) revealed that leptin favors the use of glucose for biosynthesis. These results point towards a role of leptin in metabolic reprogramming, consisting of an enhanced use of glucose for biosynthesis and lipids for energy production. This metabolic adaptations induced by leptin may provide benefits for MCF-7 growth and give support to the reverse Warburg effect described in breast cancer.

  10. Cubic meter volume optical coherence tomography

    Science.gov (United States)

    WANG, ZHAO; POTSAID, BENJAMIN; CHEN, LONG; DOERR, CHRIS; LEE, HSIANG-CHIEH; NIELSON, TORBEN; JAYARAMAN, VIJAYSEKHAR; CABLE, ALEX E.; SWANSON, ERIC; FUJIMOTO, JAMES G.

    2017-01-01

    Optical coherence tomography (OCT) is a powerful three-dimensional (3D) imaging modality with micrometer-scale axial resolution and up to multi-GigaVoxel/s imaging speed. However, the imaging range of high-speed OCT has been limited. Here, we report 3D OCT over cubic meter volumes using a long coherence length, 1310 nm vertical-cavity surface-emitting laser and silicon photonic integrated circuit dual-quadrature receiver technology combined with enhanced signal processing. We achieved 15 µm depth resolution for tomographic imaging at a 100 kHz axial scan rate over a 1.5 m range. We show 3D macroscopic imaging examples of a human mannequin, bicycle, machine shop gauge blocks, and a human skull/brain model. High-bandwidth, meter-range OCT demonstrates new capabilities that promise to enable a wide range of biomedical, scientific, industrial, and research applications. PMID:28239628

  11. Black holes in Einsteinian cubic gravity

    CERN Document Server

    Hennigar, Robie A

    2016-01-01

    Using numerical and perturbative methods, we construct the first examples of black hole solutions in Einsteinian cubic gravity and study their thermodynamics. Focusing first on four dimensional solutions, we show that these black holes have a novel equation of state in which the pressure is a quadratic function of the temperature. Despite this, they undergo a first order phase transition with associated van der Waals behaviour. We then construct perturbative solutions for general $D \\ge 5$ and study the properties of these solutions for $D=5$ and $D=6$ in particular. We find novel examples of zeroth order phase transitions and find super-entropic behaviour over a large portion of the parameter space. We analyse the specific heat, determining that the black holes are thermodynamically stable over large regions of parameter space.

  12. Triangulation of cubic panorama for view synthesis.

    Science.gov (United States)

    Zhang, Chunxiao; Zhao, Yan; Wu, Falin

    2011-08-01

    An unstructured triangulation approach, new to our knowledge, is proposed to apply triangular meshes for representing and rendering a scene on a cubic panorama (CP). It sophisticatedly converts a complicated three-dimensional triangulation into a simple three-step triangulation. First, a two-dimensional Delaunay triangulation is individually carried out on each face. Second, an improved polygonal triangulation is implemented in the intermediate regions of each of two faces. Third, a cobweblike triangulation is designed for the remaining intermediate regions after unfolding four faces to the top/bottom face. Since the last two steps well solve the boundary problem arising from cube edges, the triangulation with irregular-distribution feature points is implemented in a CP as a whole. The triangular meshes can be warped from multiple reference CPs onto an arbitrary viewpoint by face-to-face homography transformations. The experiments indicate that the proposed triangulation approach provides a good modeling for the scene with photorealistic rendered CPs.

  13. Black holes in a cubic Galileon universe

    CERN Document Server

    Babichev, Eugeny; Lehébel, Antoine; Moskalets, Tetiana

    2016-01-01

    We find and study the properties of black hole solutions for a subclass of Horndeski theory including the cubic Galileon term. The theory under study has shift symmetry but not reflection symmetry for the scalar field. The Galileon is assumed to have linear time dependence characterized by a velocity parameter. We give analytic 3-dimensional solutions that are akin to the BTZ solutions but with a non-trivial scalar field that modifies the effective cosmological constant. We then study the 4-dimensional asymptotically flat and de Sitter solutions. The latter present three different branches according to their effective cosmological constant. For two of these branches, we find families of black hole solutions, parametrized by the velocity of the scalar field. These spherically symmetric solutions, obtained numerically, are different from GR solutions close to the black hole event horizon, while they have the same de-Sitter asymptotic behavior. The velocity parameter represents black hole primary hair.

  14. Finite element differential forms on cubical meshes

    CERN Document Server

    Arnold, Douglas N

    2012-01-01

    We develop a family of finite element spaces of differential forms defined on cubical meshes in any number of dimensions. The family contains elements of all polynomial degrees and all form degrees. In two dimensions, these include the serendipity finite elements and the rectangular BDM elements. In three dimensions they include a recent generalization of the serendipity spaces, and new H(curl) and H(div) finite element spaces. Spaces in the family can be combined to give finite element subcomplexes of the de Rham complex which satisfy the basic hypotheses of the finite element exterior calculus, and hence can be used for stable discretization of a variety of problems. The construction and properties of the spaces are established in a uniform manner using finite element exterior calculus.

  15. Capturing dynamic cation hopping in cubic pyrochlores

    Science.gov (United States)

    Brooks Hinojosa, Beverly; Asthagiri, Aravind; Nino, Juan C.

    2011-08-01

    In direct contrast to recent reports, density functional theory predicts that the most stable structure of Bi2Ti2O7 pyrochlore is a cubic Fd3¯m space group by accounting for atomic displacements. The displaced Bi occupies the 96g(x,x,z) Wyckoff position with six equivalent sites, which create multiple local minima. Using nudged elastic band method, the transition states of Bi cation hopping between equivalent minima were investigated and an energy barrier between 0.11 and 0.21 eV was determined. Energy barriers associated with the motion of Bi between equivalent sites within the 96g Wyckoff position suggest the presence of dielectric relaxation in Bi2Ti2O7.

  16. On the plane-wave cubic vertex

    CERN Document Server

    Lucietti, J; Sinha, A K; Lucietti, James; Schäfer-Nameki, Sakura; Sinha, Aninda

    2004-01-01

    The exact bosonic Neumann matrices of the cubic vertex in plane-wave light-cone string field theory are derived using the contour integration techniques developed in our earlier paper. This simplifies the original derivation of the vertex. In particular, the Neumann matrices are written in terms of \\mu-deformed Gamma-functions, thus casting them into a form that elegantly generalizes the well-known flat-space solution. The asymptotics of the \\mu-deformed Gamma-functions allow one to determine the large-\\mu behaviour of the Neumann matrices including exponential corrections. We provide an explicit expression for the first exponential correction and make a conjecture for the subsequent exponential correction terms.

  17. Polarization conversion in cubic Raman crystals

    Science.gov (United States)

    McKay, Aaron; Sabella, Alexander; Mildren, Richard P.

    2017-01-01

    Nonlinear conversion of unpolarized beams to lower frequencies is generally inefficient in c(2) materials, as it is challenging to achieve phase-matching for input ordinary and extraordinary beams simultaneously in the normal dispersion regime. Here, we show that cubic Raman crystals having doubly and triply degenerate (E and F type) modes provide a method for efficient nonlinear frequency downconversion of an unpolarized beam and yield a linearly polarized output state. Using Mueller calculus, optimal crystal directions for such polarization conversion are determined. Using diamond, an example of an F-class Raman crystal, we have verified that such conversion is possible with near quantum-defect-limited slope efficiency and a linear polarization contrast of more than 23.9 dB. PMID:28169327

  18. On the Stability of Cubic Galileon Accretion

    CERN Document Server

    Bergliaffa, Santiago P E

    2016-01-01

    We examine the stability of steady-state galileon accretion for the case of a Schwarzshild black hole. Considering the galileon action up to the cubic term in a static and spherically symmetric background we obtain the general solution for the equation of motion which is divided in two branches. By perturbing this solution we define an effective metric which determines the propagation of fluctuations. In this general picture we establish the position of the sonic horizon together with the matching condition of the two branches on it. Restricting to the case of a Schwarzschild background, we show, via the analysis of the energy of the perturbations and its time derivative, that the accreting field is linearly stable.

  19. The Hedgehog signalling pathway mediates drug response of MCF-7 mammosphere cells in breast cancer patients.

    Science.gov (United States)

    He, Miao; Fu, Yingzi; Yan, Yuanyuan; Xiao, Qinghuan; Wu, Huizhe; Yao, Weifan; Zhao, Haishan; Zhao, Lin; Jiang, Qian; Yu, Zhaojin; Jin, Feng; Mi, Xiaoyi; Wang, Enhua; Cui, Zeshi; Fu, Liwu; Chen, Jianju; Wei, Minjie

    2015-11-01

    BCSCs (breast cancer stem cells) have been shown to be resistant to chemotherapy. However, the mechanisms underlying BCSC-mediated chemoresistance remain poorly understood. The Hh (Hedgehog) pathway is important in the stemness maintenance of CSCs. Nonetheless, it is unknown whether the Hh pathway is involved in BCSC-mediated chemoresistance. In the present study, we cultured breast cancer MCF-7 cells in suspension in serum-free medium to obtain BCSC-enriched MCF-7 MS (MCF-7 mammosphere) cells. We showed that MCF-7 MS cells are sensitive to salinomycin, but not paclitaxel, distinct from parent MCF-7 cells. The expression of the critical components of Hh pathway, i.e., PTCH (Patched), SMO (Smoothened), Gli1 and Gli2, was significantly up-regulated in MCF-7 MS cells; salinomycin, but not paclitaxel, treatment caused a remarkable decrease in expression of those genes in MCF-7 MS cells, but not in MCF-7 cells. Salinomycin, but not paclitaxel, increased apoptosis, decreased the migration capacity of MCF-7 MS cells, accompanied by a decreased expression of c-Myc, Bcl-2 and Snail, the target genes of the Hh pathway. The salinomycin-induced cytotoxic effect could be blocked by Shh (Sonic Hedgehog)-mediated Hh signalling activation. Inhibition of the Hh pathway by cyclopamine could sensitize MCF-7 MS cells to paclitaxel. In addition, salinomycin, but not paclitaxel, significantly reduced the tumour growth, accompanied by decreased expression of PTCH, SMO, Gli1 and Gli2 in xenograft tumours. Furthermore, the expression of SMO and Gli1 was positively correlated with the expression of CD44+ / CD24-, and the expression of SMO and Gli1 in CD44+ / CD24- tissues was associated with a significantly shorter OS (overall survival) and DFS (disease-free survival) in breast cancer patients receiving chemotherapy.

  20. Low pressure growth of cubic boron nitride films

    Science.gov (United States)

    Ong, Tiong P. (Inventor); Shing, Yuh-Han (Inventor)

    1997-01-01

    A method for forming thin films of cubic boron nitride on substrates at low pressures and temperatures. A substrate is first coated with polycrystalline diamond to provide a uniform surface upon which cubic boron nitride can be deposited by chemical vapor deposition. The cubic boron nitride film is useful as a substitute for diamond coatings for a variety of applications in which diamond is not suitable. any tetragonal or hexagonal boron nitride. The cubic boron nitride produced in accordance with the preceding example is particularly well-suited for use as a coating for ultra hard tool bits and abrasives, especially those intended to use in cutting or otherwise fabricating iron.

  1. Shape preserving rational cubic spline for positive and convex data

    Directory of Open Access Journals (Sweden)

    Malik Zawwar Hussain

    2011-11-01

    Full Text Available In this paper, the problem of shape preserving C2 rational cubic spline has been proposed. The shapes of the positive and convex data are under discussion of the proposed spline solutions. A C2 rational cubic function with two families of free parameters has been introduced to attain the C2 positive curves from positive data and C2 convex curves from convex data. Simple data dependent constraints are derived on free parameters in the description of rational cubic function to obtain the desired shape of the data. The rational cubic schemes have unique representations.

  2. Effect of Reaction Developing Training on Audio-Visual Feet Reaction Time in Wrestlers

    Science.gov (United States)

    Kaya, Mustafa

    2016-01-01

    Reaction time is one of the most determinative elements for a successful sports performance. The purpose of this study was to investigate the effect of 12-week feet reaction developing trainings upon feet reaction time of females at 11-13 age interval. Volunteer sportsmen between 11 and 13 age interval who were active in Tokat Provincial…

  3. Feet distance and static postural balance: implication on the role of natural stance.

    Science.gov (United States)

    Kim, Ji-Won; Kwon, Yuri; Jeon, Hyung-Min; Bang, Min-Jung; Jun, Jae-Hoon; Eom, Gwang-Moon; Lim, Do-Hyung

    2014-01-01

    The purpose of this study was to investigate 1) the effect of feet distance on static postural balance and 2) the location of natural feet distance and its possible role in the relationship of feet distance and postural balance. Static balance tests were performed on a force platform for 100 s with six different feet distances (0, 5, 10, 15, 20, 25 cm). Measures of postural balance included mean amplitude of horizontal ground reaction force (GRF) as well as the mean distance and velocity of the center of pressure (COP). All measures were discomposed into anterioposterior and mediolateral directions. ANOVA and post-hoc comparison were performed for all measures with feet distance as an independent factor. Also measured was the feet distance at the natural stance preferred by each subject. All measures significantly varied with feet distance (ppostural control) in an inverted pendulum model with the horizontal GRF ignored. On the other hand, horizontal GRF is the direct cause of horizontal acceleration of a center of mass. The present result on horizontal GRF shows that the effort of postural control is minimized around the feet distance of natural standing and implies why the natural stance is preferred.

  4. Energy storage and release of prosthetic feet Part 1: Biomechanical analysis related to user benefits

    NARCIS (Netherlands)

    Postema, K.; Hermens, H.J.; Vries, de J.; Koopman, H.F.J.M.; Eisma, W.H.

    1997-01-01

    The energy storing and releasing behaviour of 2 energy storing feet (ESF) and 2 conventional prosthetic feet (CF) were compared (ESF: Otto Bock Dynamic Pro and Hanger Quantum; CF: Otto Bock Multi Axial and Otto Bock Lager). Ten trans-tibial amputees were selected. The study was designed as a double-

  5. PUMA gene transfection can enhance the sensitivity of epirubicin-induced apoptosis of MCF-7 breast cancer cells.

    Science.gov (United States)

    Sun, C-G; Zhuang, J; Teng, W-J; Wang, Z; Du, S-S

    2015-05-29

    We explored whether p53 upregulated modulator of apoptosis (PUMA) gene transfection could enhance the sensitivity of epirubicin-induced apoptosis of MCF-7 breast cancer cells. The liposome-mediated recombinant eukaryotic expression vector PU-MA-pCDNA3 and empty vector plasmid were stably transfected into MCF-7 cells. Epirubicin (0.01-100 μM) was applied to MCF-7, MCF-7/PUMA, and MCF-7/pCDNA3 cells for 72 h. The MTT assay was used to calculate the cell survival rate in each group, and the 50% inhibitory concentration (IC50) was calculated. The IC50 values of epirubicin in MCF-7, MCF-7/PUMA, and MCF-7/pCDNA3 cells were 13 ± 1.4, 1.8 ± 0.2, and 10.7 ± 1.3 μM, respectively. The sensitivity of MCF-7/PUMA cells to epirubicin increased 7.2-fold. Epirubicin induced apoptosis in MCF-7 cells dose-dependently, but MCF-7/PUMA cell-induced apoptosis was more significant compared to controls. Low concentrations of epirubicin (0.1 μM) caused low levels of apoptosis of MCF-7/pCDNA3 (1.15 ± 0.26%) and MCF-7 cells (0.9 ± 0.24%), but significantly induced apoptosis of MCF-7/PUMA cells (6.44 ± 1.46%). High epirubicin concentration (1 μM) induced apoptosis in each group, but the epirubicin MCF-7/PUMA apoptosis rate (35.47 ± 9.36%) was significantly higher than that of MCF-7 (12.6 ± 3.73%) and MCF-7/ pCDNA3 (15.2 ± 5.17%) cells (P PUMA protein expression in MCF-7/PUMA cells was significantly higher than that in MCF-7 and MCF-7/pCDNA3 cells by Western blot analysis. There-fore, stable transfection of PUMA can significantly enhance epirubicin-induced apoptosis sensitivity of MCF-7 breast cancer cells.

  6. Hesperidin as a preventive resistance agent in MCF-7 breast cancer cells line resistance to doxorubicin

    Institute of Scientific and Technical Information of China (English)

    Rifki Febriansah; Dyaningtyas Dewi PP; Sarmoko; Nunuk Aries Nurulita; Edy Meiyanto; Agung Endro Nugroho

    2014-01-01

    Objective:To evaluate of hesperidin to overcome resistance of doxorubicin in MCF-7 resistant doxorubicin cells (MCF-7/Dox) in cytotoxicity apoptosis and P-glycoprotein (Pgp) expression in combination with doxorubicin. Methods:The cytotoxic properties, 50%inhibition concentration (IC50) and its combination with doxorubicin in MCF-7 cell lines resistant to doxorubicin (MCF-7/Dox) cells were determined using MTT assay. Apoptosis induction was examined by double staining assay using ethidium bromide-acridine orange. Immunocytochemistry assay was performed to determine the level and localization of Pgp. Results: Single treatment of hesperidin showed cytotoxic activity on MCF-7/Dox cells with IC50 value of 11 µmol/L. Thus, combination treatment from hesperidin and doxorubicin showed addictive and antagonist effect (CI>1.0). Hesperidin did not increase the apoptotic induction, but decreased the Pgp expressions level when combined with doxorubicin in low concentration. Conclusions: Hesperidin has cytotoxic effect on MCF-7/Dox cells with IC50 of 11 µmol/L. Hesperidin did not increased the apoptotic induction combined with doxorubicin. Co-chemotherapy application of doxorubicin and hesperidin on MCF-7/Dox cells showed synergism effect through inhibition of Pgp expression.

  7. A new MCF-7 breast cancer cell line resistant to the arzoxifene metabolite desmethylarzoxifene

    DEFF Research Database (Denmark)

    Freddie, Cecilie T; Christensen, Gitte Lund; Lykkesfeldt, Anne E

    2004-01-01

    estrogenic effects than tamoxifen on gene expression. A cell line with acquired resistance to ARZm (MCF-7/ARZm(R)-1) was established from MCF-7 cells. MCF-7/ARZm(R)-1 cells responded to treatment with tamoxifen and the pure antiestrogen ICI 182,7870. The estrogen receptor alpha (ERalpha) level in MCF-7/ARZm......The development of resistance in tamoxifen-treated breast cancer patients and the estrogenic side effects of tamoxifen have lead to the design of many new drugs. The new SERM arzoxifene and its active metabolite desmethylarzoxifene (ARZm) inhibits growth of breast cancer cells and has less......(R)-1 cells was lower than in MCF-7 cells due to a destabilization of the receptor by ARZm. A significant reduction in the mRNA and protein level of some estrogen-regulated genes was observed in MCF-7/ARZm(R)-1 compared to MCF-7. However, both the level of the ERalpha and several ER-regulated gene...

  8. CRACK PROBLEM UNDER SHEAR LOADING IN CUBIC QUASICRYSTAL

    Institute of Scientific and Technical Information of China (English)

    周旺民; 范天佑; 尹姝媛

    2003-01-01

    The axisymmetric elasticity problem of cubic quasicrystal is reduced to a single higher-order partial differential equation by introducing a displacement function. Based on the work, the analytic solutions of elastic field of cubic quasicrystal with a penny-shaped crack under the shear loading are found, and the stress intensity factor and strain energy release rate are determined.

  9. Cubic Polynomials with Real or Complex Coefficients: The Full Picture

    Science.gov (United States)

    Bardell, Nicholas S.

    2016-01-01

    The cubic polynomial with real coefficients has a rich and interesting history primarily associated with the endeavours of great mathematicians like del Ferro, Tartaglia, Cardano or Vieta who sought a solution for the roots (Katz, 1998; see Chapter 12.3: The Solution of the Cubic Equation). Suffice it to say that since the times of renaissance…

  10. An application of Cubical Cohomology to Adinkras and Supersymmetry Representations

    CERN Document Server

    Doran, Charles; Landweber, Greg

    2012-01-01

    An Adinkra is a class of graphs with certain signs marking its vertices and edges, which encodes off-shell representations of the super Poincar\\'e algebra. The markings on the vertices and edges of an Adinkra are cochains for cubical cohomology. This article explores the cubical cohomology of Adinkras, treating these markings analogously to characteristic classes on smooth manifolds.

  11. Doxycycline Induces Expression of P Glycoprotein in MCF-7 Breast Carcinoma Cells

    Science.gov (United States)

    Mealey, Katrina L.; Barhoumi, Rola; Burghardt, Robert C.; Safe, Stephen; Kochevar, Deborah T.

    2002-01-01

    P-glycoprotein (P-gp) overexpression by tumor cells imparts resistance to multiple antineoplastic chemotherapeutic agents (multiple drug resistance). Treatment of tumor cells with chemotherapeutic agents such as anthracyclines, epipodophyllotoxins, and Vinca alkaloids results in induction of P-gp expression. This study was performed to determine if clinically relevant antimicrobial drugs (i.e., drugs that are used to treat bacterial infections in cancer patients) other than antineoplastic agents can induce expression of P-gp in MCF-7 breast carcinoma cells. Expression of P-gp and MDR1 mRNA was determined in samples from MCF-7 cells that were treated in culture with doxorubicin (positive control) and the antimicrobial drugs doxycycline, piperacillin, and cefoperazone. The functional status of P-gp was assessed using laser cytometry to determine intracellular doxorubicin concentrations. The MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay was used to determine if the cytotoxicity of experimental drugs was related to their ability to induce P-gp expression. MCF-7 cells treated with doxycycline (MCF-7/doxy) were stimulated to overexpress P-gp, whereas cells treated with piperacillin and cefoperazone did not overexpress P-gp. MCF-7/doxy cells were compared to a positive-control subline, MCF-7/Adr, previously selected for doxorubicin resistance, and to MCF-7 cells treated with doxorubicin (MCF-7/doxo). All three sublines overexpressed P-gp and MDR1 mRNA and accumulated less intracellular doxorubicin than did control MCF-7 cells. P-gp expression was induced only by experimental drugs that were cytotoxic (doxorubicin and doxycycline). Doxycycline, a drug that has been used for treatment of bacterial infections in cancer patients, can induce functional P-gp expression in cancer cells, resulting in multidrug resistance. PMID:11850258

  12. Rational Cubics and Conics Representation: A Practical Approach

    Directory of Open Access Journals (Sweden)

    M. Sarfraz

    2012-08-01

    Full Text Available A rational cubic spline, with one family of shape parameters, has been discussed with the view to its application in Computer Graphics. It incorporates both conic sections and parametric cubic curves as special cases. The parameters (weights, in the description of the spline curve can be used to modify the shape of the curve, locally and globally, at the knot intervals. The rational cubic spline attains parametric   smoothness whereas the stitching of the conic segments preserves visually reasonable smoothness at the neighboring knots. The curve scheme is interpolatory and can plot parabolic, hyperbolic, elliptic, and circular splines independently as well as bits and pieces of a rational cubic spline.Key Words: Computer Graphics, Interpolation, Spline, Conic, Rational Cubic

  13. On cubic equations over $P-$adic field

    CERN Document Server

    Mukhamedov, Farrukh; Saburov, Mansoor

    2012-01-01

    We provide a solvability criteria for a depressed cubic equation in domains $\\bz_p^{*},\\bz_p,\\bq_p$. We show that, in principal, the Cardano method is not always applicable for such equations. Moreover, the numbers of solutions of the depressed cubic equation in domains $\\bz_p^{*},\\bz_p,\\bq_p$ are provided. Since $\\bbf_p\\subset\\bq_p,$ we generalize J.-P. Serre's \\cite{JPSJ} and Z.H.Sun's \\cite{ZHS1,ZHS3} results concerning with depressed cubic equations over the finite field $\\bbf_p$. Finally, all depressed cubic equations, for which the Cardano method could be applied, are described and the $p-$adic Cardano formula is provided for those cubic equations.

  14. A Pilot Study on Gait Kinematics of Old Women with Bound Feet

    Directory of Open Access Journals (Sweden)

    Yan Zhang

    2015-01-01

    Full Text Available Foot binding has a long and influential history in China. Little is known about biomechanical changes in gait caused by bound foot. The purpose of this study was to investigate the differences in lower limb kinematics between old women with bound feet and normal feet during walking. Six old women subjects (three with bound feet and three controls with normal feet volunteered to participate in this study. Video data were recorded with a high speed video camera and analysed in the SIMI motion analysis software. Compared to normal controls, bound feet subjects had faster gait cadence with shorter stride length as well as smaller ankle and knee range of motion (ROM. During preswing phase, ankle remained to be dorsiflexion for bound foot subjects. The data from bound foot group also demonstrated that toe vertical displacement increased continuously during whole swing phase without a minimum toe clearance (MTC. The findings indicate that older women with bound feet exhibit significant differences in gait pattern compared to those with normal feet, which is characterised by disappeared propulsion/push-off and reduced mobility of lower limb segments.

  15. The Body Center Cubic Quark Lattice Model

    CERN Document Server

    Lin Xu, Jiao

    2004-01-01

    The Standard Model while successful in many ways is incomplete; many questions remain. The origin of quark masses and hadronization of quarks are awaiting an answer. From the Dirac sea concept, we infer that two kinds of elementary quarks (u(0) and d(0)) constitute a body center cubic (BCC) quark lattice with a lattice constant a < $10^{-18}$m in the vacuum. Using energy band theory and the BCC quark lattice, we can deduce the rest masses and the intrinsic quantum numbers (I, S, C, b and Q) of quarks. With the quark spectrum, we deduce a baryon spectrum. The theoretical spectrum is in agreement well with the experimental results. Not only will this paper provide a physical basis for the Quark Model, but also it will open a door to study the more fundamental nature at distance scales <$10^{-18}$m. This paper predicts some new quarks $u_{c}$(6490) and d$_{b}$(9950), and new baryons $\\Lambda_{c}^{+}$(6500), $\\Lambda_{b}^{0}$(9960).

  16. Inertial Sensor-Based Two Feet Motion Tracking for Gait Analysis

    Directory of Open Access Journals (Sweden)

    Tran Nhat Hung

    2013-04-01

    Full Text Available Two feet motion is estimated for gait analysis. An inertial sensor is attached on each shoe and an inertial navigation algorithm is used to estimate the movement of both feet. To correct inter-shoe position error, a camera is installed on the right shoe and infrared LEDs are installed on the left shoe. The proposed system gives key gait analysis parameters such as step length, stride length, foot angle and walking speed. Also it gives three dimensional trajectories of two feet for gait analysis.

  17. Inertial sensor-based two feet motion tracking for gait analysis.

    Science.gov (United States)

    Hung, Tran Nhat; Suh, Young Soo

    2013-04-29

    Two feet motion is estimated for gait analysis. An inertial sensor is attached on each shoe and an inertial navigation algorithm is used to estimate the movement of both feet. To correct inter-shoe position error, a camera is installed on the right shoe and infrared LEDs are installed on the left shoe. The proposed system gives key gait analysis parameters such as step length, stride length, foot angle and walking speed. Also it gives three dimensional trajectories of two feet for gait analysis.

  18. Analysis of experience of feet functions perfection in rhythmic gymnastic exercises

    Directory of Open Access Journals (Sweden)

    Nesterova T.V.

    2009-10-01

    Full Text Available Trainers and gymnasts take the problem of the special preparation feet and developments of method of its perfection to the number of the actual. The results of the pedagogical testing are shown that basic (basic, pushed, amortisation and specific (aesthetic, manipulation, integral functions feet have a different degree of display. They will be realized in exercises on all of the stages of long-term preparation of sportswomen. Most dynamic perfection of functions feet gymnasts take place on the stages of initial and preliminary base preparation.

  19. Establishment of a paclitaxel resistant human breast cancer cell strain (MCF-7/Taxol) and intracellular paclitaxel binding protein analysis.

    Science.gov (United States)

    Zuo, K-Q; Zhang, X-P; Zou, J; Li, D; Lv, Z-W

    2010-01-01

    Multidrug resistance of tumours is one of the most important factors that leads to chemotherapy failure. A multidrug-resistant breast cancer cell line, MCF-7/Taxol, was established from the drug-sensitive parent cell line MCF-7. The biological properties of MCF-7/Taxol, including its drug resistance profile and profile of paclitaxel binding proteins, were analysed and compared with the parent cell line. A number of paclitaxel binding proteins were present in MCF-7 cells but absent from MCF-7/Taxol cells, namely heat shock protein 90, actinin and dermcidin precursor. The identification of differential paclitaxel binding proteins between the multidrug-resistant MCF-7/Taxol cell line and the parent drug-sensitive cell line MCF-7 provides insight into possible mechanisms involved in resistance to these chemotherapy drugs.

  20. Molecular Characteristics of Breast Cancer Cell Line MCF-7%乳腺癌MCF-7细胞的分子生物学特征

    Institute of Scientific and Technical Information of China (English)

    叶静; 李明华; 龙霞; 万汇涓; 范昭

    2012-01-01

    Objective To study the molecular characteristics of breast cancer cell line MCF-7. Methods Methylations of Stratifin and CyclinD2 genes were examined by methylation-specific polymerase chain reaction( MSP ). Expressions of Stratifin, CyclinD2 and Dnmt3b genes mRNA were detected by RT-PCR. Results Unmethylation and high mRNA level of Stratifin gene, complete methylation and expression deletion of CyclinD2 gene, significant expression of Dnmt3b gene were showed in breast cancer cell line MCF-7. Conclusion Methylations of Stratifin and CyclinD2 genes maybe down-regulate mRNA expressions. These molecular characteristics provide certain reference to epigenetic study of breast cancer.%目的 研究乳腺癌MCF-7细胞的分子生物学特征.方法 采用甲基化特异性PCR(MSP),对MCF-7细胞进行Stratifin和CyclinD2基因甲基化检测;采用RT-PCR法,检测Stratifin、CyclinD2和Dnmt3b基因的mRNA表达.结果 乳腺癌MCF-7细胞系中,Stratifin基因是非甲基化的,mRNA表达水平较高;CyclinD2基因完全甲基化,mRNA表达缺失;Dnmt3b基因呈明显表达.结论 Stratifin和CyclinD2基因的甲基化发生,可能下调其mRNA的转录表达,MCF-7细胞的这些分子生物学特性可为乳腺癌的表观遗传学研究提供一定的参考价值.

  1. Healing of ulcers on the feet correlated with distal blood pressure measurements in occlusive arterial disease

    DEFF Research Database (Denmark)

    Holstein, P; Lassen, N A

    1980-01-01

    The frequency of healing in subchronic ulcers in 66 feet in 62 patients with arterial occlusive disease was correlated with the systolic digital blood pressure (SDBP) and the systolic ankle blood pressure (SABP), both measured with a strain gauge, and with the skin perfusion pressure on the heel...... of healing correlated significantly with the three distal blood pressure parameters investigated, the closest correlation being with the SDBP measured at the final examination, i.e. just after healing of the ulcer or just before an inevitable major amputation. Of the 22 cases with SDBP below 20 mmHg only two...... (SPPH) as measured with a photocell. Thirty-two patients (35 feet with ulcerations) had diabetes mellitus. The treatment was conservative. In 42 feet the ulcers healed after an average period of 5.8 months; in 24 feet major amputation became necessary after an average of 4.3 months. The frequency...

  2. Normal Values of Metatarsal Parabola Arch in Male and Female Feet

    Directory of Open Access Journals (Sweden)

    Gabriel Domínguez-Maldonado

    2014-01-01

    Full Text Available There is not any method to measure metatarsal protrusion in the whole metatarsal. The aim of this research is to know the normal metatarsal parabola in male and female feet. The system of measurement devised by Hardy and Clapham to evaluate the protrusion between metatarsals I and II was adapted to study the whole metatarsal parabola and applied to the five metatarsals of 169 normal feet, 72 female feet and 97 male feet. Authors measured all metatarsal protrusion relative to metatarsal II. The results obtained show a female metatarsal protrusion relative to metatarsal II of +1.27% for metatarsal I, -3.36% for metatarsal III, -8.34% for metatarsal IV, and -15.54% for metatarsal V. Data obtained for male metatarsal parabola were +0.5% for metatarsal I, -3.77 for metatarsal III, -9.57 for metatarsal IV, and -17.05 for metatarsal V. Differences between both metatarsal parabola were significant.

  3. Normal values of metatarsal parabola arch in male and female feet.

    Science.gov (United States)

    Domínguez-Maldonado, Gabriel; Munuera-Martinez, Pedro V; Castillo-López, José Manuel; Ramos-Ortega, Javier; Albornoz-Cabello, Manuel

    2014-01-01

    There is not any method to measure metatarsal protrusion in the whole metatarsal. The aim of this research is to know the normal metatarsal parabola in male and female feet. The system of measurement devised by Hardy and Clapham to evaluate the protrusion between metatarsals I and II was adapted to study the whole metatarsal parabola and applied to the five metatarsals of 169 normal feet, 72 female feet and 97 male feet. Authors measured all metatarsal protrusion relative to metatarsal II. The results obtained show a female metatarsal protrusion relative to metatarsal II of +1.27% for metatarsal I, -3.36% for metatarsal III, -8.34% for metatarsal IV, and -15.54% for metatarsal V. Data obtained for male metatarsal parabola were +0.5% for metatarsal I, -3.77 for metatarsal III, -9.57 for metatarsal IV, and -17.05 for metatarsal V. Differences between both metatarsal parabola were significant.

  4. Evaluation of caudal epidural anesthesia efficacy by measurement of feet skin temperature in children

    Directory of Open Access Journals (Sweden)

    M. Yu. Kurochkin

    2015-04-01

    Full Text Available Caudal epidural anesthesia in children is not performed in pure form, but only in combination with superficial general anesthesia. Therefore, a search for reliable evaluation criteria of the caudal epidural block onset in children remains actual. Aim. To evaluate effectiveness of caudal epidural anesthesia efficacy by measurement of feet skin temperature in children. Methods and results. We investigated feet skin temperature before the caudal blockade by bupivacaine and after 15–20 minutes in 30 children. The control group included 20 children who underwent total intravenous anesthesia. The study showed that feet skin temperature after caudal blockade significantly increased from 30,1±0,15°C to 33,0±0,1°C (10% and in the control group it did not change significantly. Conclusion. Thus, feet skin thermometry may be considered to be a reliable non-invasive method for assessing the onset of the caudal block.

  5. Foot deformation during walking: differences between static and dynamic 3D foot morphology in developing feet.

    Science.gov (United States)

    Barisch-Fritz, Bettina; Schmeltzpfenning, Timo; Plank, Clemens; Grau, Stefan

    2014-01-01

    The complex functions of feet require a specific composition, which is progressively achieved by developmental processes. This development should take place without being affected by footwear. The aim of this study is to evaluate differences between static and dynamic foot morphology in developing feet. Feet of 2554 participants (6-16 years) were recorded using a new scanner system (DynaScan4D). Each foot was recorded in static half and full weight-bearing and during walking. Several foot measures corresponding to those used in last construction were calculated. The differences were identified by one-way ANOVA and paired Student's t-test. Static and dynamic values of each foot measure must be considered to improve the fit of footwear. In particular, footwear must account for the increase of forefoot width and the decrease of midfoot girth. Furthermore, the toe box should have a more rounded shape. The findings are important for the construction of footwear for developing feet.

  6. Evaluation of MCF10A as a Reliable Model for Normal Human Mammary Epithelial Cells.

    Directory of Open Access Journals (Sweden)

    Ying Qu

    Full Text Available Breast cancer is the most common cancer in women and a leading cause of cancer-related deaths for women worldwide. Various cell models have been developed to study breast cancer tumorigenesis, metastasis, and drug sensitivity. The MCF10A human mammary epithelial cell line is a widely used in vitro model for studying normal breast cell function and transformation. However, there is limited knowledge about whether MCF10A cells reliably represent normal human mammary cells. MCF10A cells were grown in monolayer, suspension (mammosphere culture, three-dimensional (3D "on-top" Matrigel, 3D "cell-embedded" Matrigel, or mixed Matrigel/collagen I gel. Suspension culture was performed with the MammoCult medium and low-attachment culture plates. Cells grown in 3D culture were fixed and subjected to either immunofluorescence staining or embedding and sectioning followed by immunohistochemistry and immunofluorescence staining. Cells or slides were stained for protein markers commonly used to identify mammary progenitor and epithelial cells. MCF10A cells expressed markers representing luminal, basal, and progenitor phenotypes in two-dimensional (2D culture. When grown in suspension culture, MCF10A cells showed low mammosphere-forming ability. Cells in mammospheres and 3D culture expressed both luminal and basal markers. Surprisingly, the acinar structure formed by MCF10A cells in 3D culture was positive for both basal markers and the milk proteins β-casein and α-lactalbumin. MCF10A cells exhibit a unique differentiated phenotype in 3D culture which may not exist or be rare in normal human breast tissue. Our results raise a question as to whether the commonly used MCF10A cell line is a suitable model for human mammary cell studies.

  7. Cubic B-spline curve approximation by curve unclamping

    OpenAIRE

    Chen, Xiao-Diao; Ma, Weiyin; Paul, Jean-Claude

    2010-01-01

    International audience; A new approach for cubic B-spline curve approximation is presented. The method produces an approximation cubic B-spline curve tangent to a given curve at a set of selected positions, called tangent points, in a piecewise manner starting from a seed segment. A heuristic method is provided to select the tangent points. The first segment of the approximation cubic B-spline curve can be obtained using an inner point interpolation method, least-squares method or geometric H...

  8. On q-power cycles in cubic graphs

    DEFF Research Database (Denmark)

    Bensmail, Julien

    2017-01-01

    In the context of a conjecture of Erdos and Gyárfás, we consider, for any q ≥ 2, the existence of q-power cycles (i.e. with length a power of q) in cubic graphs. We exhibit constructions showing that, for every q ≥ 3, there exist arbitrarily large cubic graphs with no q-power cycles. Concerning...... the remaining case q = 2 (which corresponds to the conjecture of Erdos and Gyárfás), we show that there exist arbitrarily large cubic graphs whose only 2-power cycles have length 4 only, or 8 only....

  9. On q-power cycles in cubic graphs

    DEFF Research Database (Denmark)

    Bensmail, Julien

    2016-01-01

    In the context of a conjecture of Erdos and Gyárfás, we consider, for any q ≥ 2, the existence of q-power cycles (i.e. with length a power of q) in cubic graphs. We exhibit constructions showing that, for every q ≥ 3, there exist arbitrarily large cubic graphs with no q-power cycles. Concerning...... the remaining case q = 2 (which corresponds to the conjecture of Erdos and Gyárfás), we show that there exist arbitrarily large cubic graphs whose only 2-power cycles have length 4 only, or 8 only....

  10. [Mechanism research on the lupeol treatment on MCF-7 breast cancer cells based on cell metabonomics].

    Science.gov (United States)

    Shi, Dongdong; Kuang, Yuanyuan; Wang, Guiming; Peng, Zhangxiao; Wang, Yan; Yan, Chao

    2014-03-01

    The objective of this research is to investigate the suppressive effects of lupeol on MCF-7 breast cancer cells, and explore its mechanism on inhibiting the proliferation of MCF-7 cells based on cell metabonomics and cell cycle. Gas chromatography-mass spectrometry (GC-MS) was used in the cell metabonomics assay to identify metabolites of MCF-7 cells and MCF-7 cells treated with lupeol. Then, orthogonal partial least squares discriminant analysis (OPLS-DA) was used to process the metabolic data and model parameters of OPLS-DA were as follows: R2Ycum = 0.988, Q2Ycum = 0.964, which indicated that these two groups could be distinguished clearly. The metabolites (VIP (variable importance in the projection) > 1) were analyzed by t-test, and finally, metabolites (t < 0.05) were identified to be biomarkers. Eleven metabolites such as butanedioic acid, phosphoric acid, L-leucine and isoleucine which had a significant contribution to classification were selected and preliminarily identified due to the accurate mass. Cell cycle assay was analyzed by FACSCalibur. Since the cells in the phase of G1 were increased significantly after the treatment of lupeol, we speculated that lupeol has a blocking effect on the generation of succinyl-CoA and the reaction of substrate phosphorylation of tricarboxylic acid cycle of MCF-7 cells. This study provided a novel approach to the mechanism research on the lupeol treatment on MCF-7 breast cancer cells based on cell metabonomics.

  11. Apoptosis induced by diallyl disulfide in human breast cancer cell line MCF.71

    Institute of Scientific and Technical Information of China (English)

    Xiao-yong LEI; Shu-qiong YAO; Xu-yu ZU; Ze-xiang HUANG; Li-juan LIU; Miao ZHONG; Bing-yang ZHU; Sheng- song TANG; Duan-fang LIAO

    2008-01-01

    Aim:To investigate the effect of diallyl disulfide (DADS),a component of garlic,on apoptosis in human mammary cancer cell line (MCF-7) and its mechanisms.Methods:Cytotoxicity was analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays.Morphology of apoptotic cells was detected by acridine orange and ethidium bromide staining.Apoptotic cells stained with propidium iodide were examined using flow cytometry.Protein levels were detected by Western blot analysis.Results:DADS inhibited the proliferation of MCF-7 cells and induced the apoptotic ratio to increase rapidly.Cleavage of the caspase-3 and caspase-3 substrate poly(ADP-ribose) polymerase was observed in MCF-7 cells after 24 h of treatment with DADS.When the MCF-7 cells were signal-regulated kinase (ERK),a mitogen-activated protein kinase,was inhibited after 6 h; court N-terminal kinase (JNK),that is stress-activated protein kinase (SAPK),and p38 mitogen-aetivated protein kinase were activated after 6 h.Conclusion:These results suggest that DADS both inhibits the proliferation of MCF-7 cells and induces apoptosis of MCF-7 cells.The mechanisms may include the inhibition of ERK and the activation of the SAPK/JNK and p38 pathways.

  12. A Novel Agent Enhances the Chemotherapeutic Efficacy of Doxorubicin in MCF-7 Breast Cancer Cells

    Science.gov (United States)

    Wang, Liang; Chan, Judy Y.; Zhou, Xinhua; Cui, Guozhen; Yan, Zhixiang; Wang, Li; Yan, Ru; Di, Lijun; Wang, Yuqiang; Hoi, Maggie P.; Shan, Luchen; Lee, Simon M.

    2016-01-01

    We have previously demonstrated that DT-010, a novel conjugate of danshensu (DSS) and tetramethylpyrazine (TMP), displays anti-tumor effects in breast cancer cells both in vitro and in vivo. In the present study, we investigated whether DT-010 enhances the chemotherapeutic effect of doxorubicin (Dox) in MCF-7 breast cancer cells and exerts concurrent cardioprotective benefit at the same time. Our findings showed that DT-010 was more potent than TMP, DSS, or their combination in potentiating Dox-induced toxicity in MCF-7 cells. Co-treatment with DT-010 and Dox increased apoptosis in MCF-7 cells relative to Dox alone. Further study indicated that glycolytic capacity, glycolytic reserve and lactate level of MCF-7 cells were significantly inhibited after DT-010 treatment. DT-010 also increased the expression of the pro-survival protein GRP78, which was inhibited by co-treatment with Dox. Both endoplasmic reticulum stress inhibitor 4-PBA and knockdown of the expression of GRP78 protein potentiated DT-010-mediated apoptosis in MCF-7 cells. Moreover, DT-010 inhibited Dox-induced cardiotoxicity in H9c2 myoblasts. In conclusion, DT-010 and Dox confer synergistic anti-tumor effect in MCF-7 breast cancer cells through downregulation of the glycolytic pathway and inhibition of the expression of GRP78. Meanwhile, DT-010 also protects against Dox-induced cardiotoxicity. PMID:27559313

  13. The compressibility of cubic white and orthorhombic, rhombohedral, and simple cubic black phosphorus

    Energy Technology Data Exchange (ETDEWEB)

    Clark, Simon M; Zaug, Joseph

    2010-03-10

    The effect of pressure on the crystal structure of white phosphorus has been studied up to 22.4 GPa. The ?alpha phase was found to transform into the alpha' phase at 0.87 +- 0.04 GPa with a volume change of 0.1 +- 0.3 cc/mol. A fit of a second order Birch- Murnaghan equation to the data gave Vo = 16.94 ? 0.08 cc/mol and Ko = 6.7 +- 0.5 GPa for the alpha phase and Vo = 16.4 +- 0.1 cc/mol and Ko = 9.1 +- 0.3 GPa for the alpha' phase. The alpha' phase was found to transform to the A17 phase of black phosphorus at 2.68 +- 0.34 GPa and then with increasing pressure to the A7 and then simple cubic phase of black phosphorus. A fit of a second order Birch-Murnaghan equation to our data combined with previous measurements gave Vo = 11.43 +- 0.05 cc/mol and Ko = 34.7 +- 0.5 GPa for the A17 phase, Vo = 9.62 +- 0.01 cc/mol and Ko = 65.0 +- 0.6 GPa for the A7 phase and , Vo = 9.23 +- 0.01 cc/mol and Ko = 72.5 +- 0.3 GPa for the simple cubic phase.

  14. Foot-mediated incubation: Nazca booby (Sula granti) feet as surrogate brood patches.

    Science.gov (United States)

    Morgan, Stephanie M; Ashley-Ross, Miriam A; Anderson, David J

    2003-01-01

    Incubation in most avian species involves transferring heat from parent to egg through a highly vascularized brood patch. Some birds, however, do not develop a brood patch. Unusual among birds, these species hold their eggs under the webs of their feet, but the role of the feet in heat transfer is uncertain. Often the webs are positioned between the feathered abdomen and the egg during incubation, suggesting that either the abdomen, the feet, or both could transfer heat to the egg. We studied heat transfer from foot webs to eggs during incubation in Nazca boobies by spatially separating the feet from the abdomen using an oversized egg. We found that feet transfer heat to eggs independently of any heat that may be transferred from the abdomen. In addition, we found that incubating boobies had significantly greater vascularization in their foot webs, measured as a percentage of web area covered by vessels, than nonincubating boobies. We also found that males, whether incubating or nonincubating, had significantly less web vascularization than females. We concluded that vascularized Nazca booby feet function in the same way during incubation that vascularized brood patches do, acting as surrogate brood patches.

  15. Differential effect of methyl-, butyl- and propylparaben and 17β-estradiol on selected cell cycle and apoptosis gene and protein expression in MCF-7 breast cancer cells and MCF-10A non-malignant cells.

    Science.gov (United States)

    Wróbel, Anna Maria; Gregoraszczuk, Ewa Łucja

    2014-09-01

    Parabens are alkyl esters of p-hydroxybenzoic acid used widely as antimicrobial preservatives in consumer products, including pharmaceuticals, foods and cosmetics. We showed previously that methyl-, butyl- and propylparaben parabens, even at low doses, stimulate the proliferation of MCF-7 breast cancer cells and non-transformed MCF-10A breast epithelial cells. The present study was undertaken to determine whether this represents a direct effect on cell cycle and apoptotic gene expression. MCF-7 and MCF-10A cells were exposed to methyl, butyl- and propylparaben (20 nm) or 17β-estradiol (10 nm). Cell cycle and apoptotic gene expression were evaluated by real-time polymerase chain reaction and protein expression by Western blot. 17β-estradiol upregulated G1 /S phase genes and downregulated cell cycle progression inhibitors in both MCF-7 and MCF-10A. Upregulation of Bcl-xL and downregulation of caspase 9 was observed in MCF-7, while upregulation of Bcl-xL, BCL2L2 and caspase 9 was noted in MCF-10A. Cyclins in MCF-7 cells were not affected by any of the parabens. Methyl- and butylparaben had no effect on the expression of selected apoptotic genes in MCF-7. In MCF-10A, all parabens tested increased the expression of G1 /S phase genes, and downregulated cell cycle inhibitors. Methylparaben increased pro-survival gene. Butylparaben increased BCL2L1 gene, as did 17β-estradiol, while propylparaben upregulated both the extrinsic and intrinsic apoptotic pathways. There are differences in cell cycle and apoptosis gene expression between parabens and 17β-estradiol in MCF-7 cells. In MCF-10A cells, most of the genes activated by parabens were comparable to those activated by 17β-estradiol.

  16. Global infinite energy solutions for the cubic wave equation

    OpenAIRE

    Burq, N.; L. Thomann; Tzvetkov, N.

    2012-01-01

    International audience; We prove the existence of infinite energy global solutions of the cubic wave equation in dimension greater than 3. The data is a typical element on the support of suitable probability measures.

  17. The Coulombic Lattice Potential of Ionic Compounds: The Cubic Perovskites.

    Science.gov (United States)

    Francisco, E.; And Others

    1988-01-01

    Presents coulombic models representing the particles of a system by point charges interacting through Coulomb's law to explain coulombic lattice potential. Uses rubidium manganese trifluoride as an example of cubic perovskite structure. Discusses the effects on cluster properties. (CW)

  18. Spinning solitons in cubic-quintic nonlinear media

    Indian Academy of Sciences (India)

    Lucian-Cornel Crasovan; Boris A Malomed; Dumitru Mihalache

    2001-11-01

    We review recent theoretical results concerning the existence, stability and unique features of families of bright vortex solitons (doughnuts, or ‘spinning’ solitons) in both conservative and dissipative cubic-quintic nonlinear media.

  19. Stress Intensity of Antiplane Conjugate Cracks in Cubic Quasicrystal

    Institute of Scientific and Technical Information of China (English)

    ZHANG Lei

    2008-01-01

    Based on the theory of Muskhelishvili, the general solutions for stress and strain of conjugate cracks in cubic quasicrystal are obtained, with which the stress intensity factors of cubic quasicrystal at crack tips and the stress distribution functions of phonon and phason fields are given. The results show that though phason field is coupled with phonon field by constitutive equations, the stress intensity factors are not coupled with any other factors.

  20. Optical studies of cubic III-nitride structures

    OpenAIRE

    Powell, Ross E L

    2014-01-01

    The properties of cubic nitrides grown by molecular beam epitaxy (MBE) on GaAs (001) have been studied using optical and electrical techniques. The aim of these studies was the improvement of the growth techniques in order to improve the quality of grown nitrides intended for bulk substrate and optoelectronic device applications. We have also characterised hexagonal nanocolumn structures incorporating indium. Firstly, bulk films of cubic AlxGa1-xN with aluminium fractions (x) spanning the ...

  1. Spinor bose gases in cubic optical lattice

    Energy Technology Data Exchange (ETDEWEB)

    Mobarak, Mohamed Saidan Sayed Mohamed

    2014-01-27

    In recent years the quantum simulation of condensed-matter physics problems has resulted from exciting experimental progress in the realm of ultracold atoms and molecules in optical lattices. In this thesis we analyze theoretically a spinor Bose gas loaded into a three-dimensional cubic optical lattice. In order to account for different superfluid phases of spin-1 bosons with a linear Zeeman effect, we work out a Ginzburg-Landau theory for the underlying spin-1 Bose-Hubbard model. To this end we add artificial symmetry-breaking currents to the spin-1 Bose-Hubbard Hamiltonian in order to break the global U (1) symmetry. With this we determine a diagrammatic expansion of the grand-canonical free energy up to fourth order in the symmetry-breaking currents and up to the leading non-trivial order in the hopping strength which is of first order. As a cross-check we demonstrate that the resulting grand-canonical free energy allows to recover the mean-field theory. Applying a Legendre transformation to the grand-canonical free energy, where the symmetry-breaking currents are transformed to order parameters, we obtain the effective Ginzburg-Landau action. With this we calculate in detail at zero temperature the Mott insulator-superfluid quantum phase boundary as well as condensate and particle number density in the superfluid phase. We find that both mean-field and Ginzburg-Landau theory yield the same quantum phase transition between the Mott insulator and superfluid phases, but the range of validity of the mean-field theory turns out to be smaller than that of the Ginzburg-Landau theory. Due to this finding we expect that the Ginzburg-Landau theory gives better results for the superfluid phase and, thus, we restrict ourselves to extremize only the effective Ginzburg-Landau action with respect to the order parameters. Without external magnetic field the superfluid phase is a polar (ferromagnetic) state for anti-ferromagnetic (ferromagnetic) interactions, i.e. only the

  2. Different chemo- and endocrino-sensitivity of MCF-7 cells with or without estradiol supplement in vitro.

    Science.gov (United States)

    Tanino, H; Kubota, T; Saikawa, Y; Kuo, T H; Takeuchi, T; Kase, S; Furukawa, T; Kitajima, M; Sakurai, T; Naito, Y

    1993-01-01

    The sensitivity of MCF-7 cells to tamoxifen (TAM) and mitomycin C (MMC) was assessed in rapidly and slowly growing cells with or without estradiol supplementation, respectively. The growth of MCF-7 was inhibited by MMC in a concentration-dependent manner with or without estradiol (E2) supplementation. Preincubation with MMC suppressed subsequent E2 stimulated growth of MCF-7. TAM inhibited the growth of MCF-7 supplemented with E2 and preincubation with TAM prevented subsequent E2 stimulated growth of MCF-7. However, TAM did not inhibit the growth of MCF-7 cells in E2 free medium. These results suggested that MMC may be more effective than TAM on breast cancer cells in the dormant or slow-growth phase.

  3. MCF7/LCC9: an antiestrogen-resistant MCF-7 variant in which acquired resistance to the steroidal antiestrogen ICI 182,780 confers an early cross-resistance to the nonsteroidal antiestrogen tamoxifen

    DEFF Research Database (Denmark)

    Brünner, N; Boysen, B; Jirus, S;

    1997-01-01

    variant designated MCF7/LCC9. In contrast to 4-hydroxytamoxifen-selected MCF7/LCC2 cells, MCF7/LCC9 cells exhibit full cross-resistance to tamoxifen, despite never having been exposed to this drug. Significantly, tamoxifen cross-resistance arose early in the selection, appearing following selection...... growth of MCF7/LCC9 tumors is not affected by treatment with ICI 182,780. Although there is some evidence of tamoxifen stimulation of tumor growth, this did not reach statistical significance. If this pattern of cross-resistance occurs in some breast cancer patients, administering triphenylethylene...

  4. Dorsal sensory impairment in hands and feet of people affected by Hansen's disease in Israel.

    Science.gov (United States)

    Wexler, Ruth; Melchior, Hanna

    2007-12-01

    Sensory testing in people affected by Hansen's disease is usually performed on palms and soles only. In Israel, both palmar/plantar and dorsal aspects of limbs are routinely tested. The aim of this study was to describe the magnitude of dorsal sensory impairment (SI) in limbs and compare the frequency of SI on palms and soles with that on the dorsum of hands and feet. In a cross-sectional study, limbs of 140 patients registered at The Israel Hansen's Disease Centre during the years 1999-2003 were tested for their sensory status. Both palmar/plantar and dorsal aspects were tested using Semmes-Weinstein monofilaments. SI was defined as not feeling stimuli applied with the 2 g monofilament. SI was detected on the dorsum in 43% of sites on hands and only in 27% on palms. 64% of sites on dorsum of feet had SI compared to 53% on the soles. SI was detected in up to 18% in hands with no palmar SI, and in 6% of feet with no plantar SI. Furthermore, SI on palms and soles was found to be accompanied by dorsal SI in all hands and in 97% of feet. SI on dorsum of limbs occurs more frequently than SI on palms and soles. Therefore sensory testing should also consider inclusion of the dorsal aspect of hands and feet.

  5. Induction of Apoptosis in Human Breast Cancer (MCF7) Cells by n-Hexane Extract of Plectranthus amboinicus (Lour.) Spreng.

    OpenAIRE

    Hasibuan, Poppy Anjelisa Z.

    2016-01-01

    The n-hexane extract of Plectranthus amboinicus, (Lour.) Spreng. reduced the proliferation of MCF7 cells. The present study was carried out to evaluate the effect of the extract on human breast cancer cells viability and apoptosis. To detect apoptotic cells, MCF7 cells were stained with etydium bromide-acrydine orange (double staining method). Quantitative detectin of apoptotic cells was performed by fluorescens microscope. The growth of MCF7 was inhibited by treatment with n-h...

  6. VEGF-siRNA诱导MCF-7细胞凋亡及其机制%APOPTOSIS OF VEGF-siRNA-INDUCED MCF-7 AND ITS MECHANISM

    Institute of Scientific and Technical Information of China (English)

    张菡菡; 胡金霞; 孔丽君

    2013-01-01

    目的 探讨靶向血管内皮生长因子(VEGF) siRNA下调VEGF表达对人乳癌MCF-7细胞凋亡及凋亡相关基因survivin的影响.方法 体外设计并合成靶向VEGF mRNA的siRNA并转染至人乳癌细胞MCF-7,实验设空白对照组、脂质体对照组、阴性对照SCR组、3个浓度siRNA组(50、100、200 nmol/L),转染24 h后,AnnexinV/PI双染结合流式细胞仪测定细胞凋亡;半定量RT-PCR、细胞免疫组化技术检测转染前后MCF-7细胞survivin基因表达的变化.结果 与空白对照组比较,3个浓度siRNA组MCF 7细胞早、晚期凋亡率均增加,差异有显著性(F=35.81、30.12,q=6.08~56.53,P<0.05、0.01);survivin mRNA及蛋白表达均下调,差异有显著性(F=21.59、35.64,q=11.56~273.20,P<0.05、0.01).脂质体对照组、阴性对照SCR组与空白对照组比较,细胞凋亡率、survivin mRNA及蛋白表达差异均无统计学意义(P>0.05).结论 靶向VEGF基因siRNA转染MCF-7后诱导细胞凋亡,且与转染剂量有一定依赖关系;其分子机制与凋亡相关基因survivin表达有关.%Objective To investigate the effect of small interfering RNA (siRNA) targeting vascular endothelial growth factor (VEGF) on apoptosis and apoptosis-related gene survivin when it reduced VEGF expression in human breast cancer MCF-7 cells. Methods siRNA targeting VEGF was designed and synthesized in vitro, and transfected into MCF-7 cells. There were blank group, lipofectamine group, negative control SCR group and three siRNA concentration gradient groups (50, 100, and 200 nmol/L). At 24 hours after transfection, apoptosis was examined by FCM essay; RT-PCR and immunocytochemistry were used to examine the expression of survivin mRNA, before and after transfection. Results Compared with the blank control, the early and advanced stage apoptosis of MCF cells in the three small-dose-siRNA groups was increased with a significant difference a-mong them (F = 35. 81,30. 12 ;q — 6. 08 — 56. 53; P 0. 05

  7. Improving the reproducibility of the MCF-7 cell proliferation assay for the detection of xenoestrogens.

    Science.gov (United States)

    Payne, J; Jones, C; Lakhani, S; Kortenkamp, A

    2000-03-29

    The MCF-7 cell proliferation assay is potentially a simple and highly reproducible tool for the identification of estrogenic compounds. However, its widespread use has been complicated by the lack of a standardised protocol, resulting in considerable inter-laboratory variability. We have explored the sources of variability both in relation to cell lines and test regimens and report on optimised procedures for the identification of estrogenic agents. Two supposedly identical MCF-7 parent cell lines (designated UCL and SOP), and the BUS subline were cultured according to an existing protocol, and responses to 17-estradiol (E2) assessed. Despite yielding almost identical EC50 values, the proliferative response varied widely between cell lines from 0.98-fold over controls (UCL) to 8.9-fold (BUS) indicating major differences between them. The underlying causes may be genetic, and to assess this we used comparative genomic hybridisation (CGH), a technique which allows the detection of DNA sequence copy number changes on a genome-wide scale. Although numerous similarities existed between the different cell lines, the least oestrogen-responsive line (MCF-7/UCL) exhibited the greatest number of cytogenetic changes, many of which were not seen in MCF-7/SOP cells. We suggest that care must be taken, therefore, when choosing a cell line for MCF-7 cell-based experiments. Selecting the MCF-7/SOP line for further work, we carried out a thorough and systematic optimisation of the MCF-7 cell proliferation assay, finding that a 72-h period in oestrogen-free medium before treatment strongly influenced the cells response to E2. With 1 nM E2, proliferation increased from 1.5-fold to 6.5-fold relative to vehicle-treated controls, a response similar to that seen with MCF-7/BUS cells in the E-SCREEN protocol devised by Soto et al. With parent MCF-7 cells, other laboratories have reported only 4.5-fold increases as maximal. Here we present evidence that the choice of cell line and culture

  8. Quercetin Suppresses Twist to Induce Apoptosis in MCF-7 Breast Cancer Cells.

    Science.gov (United States)

    Ranganathan, Santhalakshmi; Halagowder, Devaraj; Sivasithambaram, Niranjali Devaraj

    2015-01-01

    Quercetin is a dietary flavonoid which exerts anti-oxidant, anti-inflammatory and anti-cancer properties. In this study, we investigated the anti-proliferative effect of quercetin in two breast cancer cell lines (MCF-7 and MDA-MB-231), which differed in hormone receptor. IC50 value (37μM) of quercetin showed significant cytotoxicity in MCF-7 cells, which was not observed in MDA-MB-231 cells even at 100μM of quercetin treatment. To study the response of cancer cells to quercetin, with respect to different hormone receptors, both the cell lines were treated with a fixed concentration (40μM) of quercetin. MCF-7 cells on quercetin treatment showed more apoptotic cells with G1 phase arrest. In addition, quercetin effectively suppressed the expression of CyclinD1, p21, Twist and phospho p38MAPK, which was not observed in MDA-MB-231 cells. To analyse the molecular mechanism of quercetin in exerting an apoptotic effect in MCF-7 cells, Twist was over-expressed and the molecular changes were observed after quercetin administration. Quercetin effectively regulated the expression of Twist, in turn p16 and p21 which induced apoptosis in MCF-7 cells. In conclusion, quercetin induces apoptosis in breast cancer cells through suppression of Twist via p38MAPK pathway.

  9. Quercetin induces apoptosis and necroptosis in MCF-7 breast cancer cells.

    Science.gov (United States)

    Khorsandi, L; Orazizadeh, M; Niazvand, F; Abbaspour, M R; Mansouri, E; Khodadadi, A

    2017-01-01

    This study investigated the quercetin (Que) effects on growth of MCF-7 human cancer breast cell line and its cellular death mechanism. Quercetin has been found to be very efficacious against many different types of cancer cells. However, the study is not sufficiently powered to demonastrate anticancer mechanisms. MCF-7cells were treated by 50 µM/ ml of Que for 48 hours. MCF-7 cells were also pretreated with 10 Μm ZVAD (apoptosis inhibitor) or 3 mM Nec-1 (necroptosis inhibitor) for evaluation of cell death induced by apoptosis or necroptosis. MTT and clonogenicity assays revealed that the Que induced a significant increase in cell viability and proliferation in presence of Nec-1 in comparison to the presence of ZVAD (p apoptosis as revealed by DAPI staining and morphology evaluations. Following Que treatment Bcl-2 expression was significantly decreased while Bax expression was significantly increased. Que in presence of Nec-1 decreased expression of Bax gene, reduced apoptotic index, increased cell viability and proliferation of MCF-7 cells in comparison to absence of Nec-1. MCF-7 cells showed a significantly increased expression of RIPK1 and RIPK3 in response to Que plus ZVAD in comparison to absence of ZVAD. Our results revealed that the high Que toxicity for breast cancer cells depends on multiple cell death pathways, which involve mainly necroptosis (Fig. 6, Ref. 21).

  10. Suberoyl bis-hydroxamic acid induces p53-dependent apoptosis of MCF-7 breast cancer cells

    Institute of Scientific and Technical Information of China (English)

    Zhi-gang ZHUANG; Fei FEI; Ying CHEN; Wei JIN

    2008-01-01

    Aim: To study the effects of suberoyl bis-hydroxamic acid (SBHA), an inhibitor of histone deacetylases, on the apoptosis of MCF-7 breast cancer cells. Meth-ods: Apoptosis in MCF-7 cells induced by SBHA was demonstrated by flow cytometric analysis, morphological observation, and DNA ladder. Mitochondrial membrane potential (△ψm) was measured using the fluorescent probe JC-1. The expressions of p53, p21, Bax, and PUMA were determined using RT-PCR or Western blotting analysis after the MCF-7 cells were treated with SBHA or p53 siRNA. Results: SBHA induced apoptosis in MCF-7 cells. The expressions of p53, p21, Bax, and PUMA were induced, and △ψm collapsed after treatment with SBHA. p53 siRNA abrogated the SBHA-induced apoptosis and the expressions of p53, p21, Bax, and PUMA. Conclusion: The activation of the p53 pathway is involved in SBHA-induced apoptosis in MCF-7 cells.

  11. Construction of single-chain variable fragment antibodies against MCF-7 breast cancer cells.

    Science.gov (United States)

    Zuhaida, A A; Ali, A M; Tamilselvan, S; Alitheen, N B; Hamid, M; Noor, A M; Yeap, S K

    2013-11-18

    A phage display library of single chain variable fragment (scFv) against MCF-7 breast cancer cells was constructed from C3A8 hybridoma cells. RNA from the C3A8 was isolated, cDNA was constructed, and variable heavy and light immunoglobulin chain gene region were amplified using PCR. The variable heavy and light chain gene regions were combined with flexible linker, linked to a pCANTAB 5E phagemid vector and electrophoresed into supE strain of Escherichia coli TG1 cells. Forty-eight clones demonstrated positive binding activity to MCF-7 breast cancer cell membrane fragments and the strongest of 48 clones was selected for analysis. The anti-MCF-7 library evaluated by SfiI and NotI digests demonstrated that anti-MCF-7 scFv antibodies possess individual patterns that should be able to recognize distinct human breast cancer cells. The C3A8 scFv, with an apparent molecular weight of 32 kDa, showed high homology (99%) with single chain antibody against rice stripe virus protein P20. In summary, the anti MCF-7 scFv antibody can be used for pretargeting breast cancer for clinical diagnosis of patients; it also has potential for therapeutic applications.

  12. Chemosensitivity of MCF-7 cells to eugenol: release of cytochrome-c and lactate dehydrogenase

    Science.gov (United States)

    Al Wafai, Rana; El-Rabih, Warde; Katerji, Meghri; Safi, Remi; El Sabban, Marwan; El-Rifai, Omar; Usta, Julnar

    2017-01-01

    Phytochemicals have been extensively researched for their potential anticancer effects. In previous study, direct exposure of rat liver mitochondria to eugenol main ingredient of clove, uncoupled mitochondria and increased F0F1ATPase activity. In the present study, we further investigated the effects of eugenol on MCF-7 cells in culture. Eugenol demonstrated: a dose-dependent decrease in viability (MTT assay), and proliferation (real time cell analysis) of MCF-7 cells, (EC50: 0.9 mM); an increase in reactive oxygen species; a decrease in ATP level and mitochondrial membrane potential (MitoPT JC-1 assay); and a release of cytochrome-c and lactate dehydrogenase (Cytotoxicity Detection Kit PLUS) into culture media at eugenol concentration >EC50. Pretreatment with the antioxidants Trolox and N-acetyl cysteine partially restored cell viability and decreased ROS, with Trolox being more potent. Expression levels of both anti- and pro-apoptotic markers (Bcl-2 and Bax, respectively) decreased with increasing eugenol concentration, with no variation in their relative ratios. Eugenol-treated MCF-7 cells overexpressing Bcl-2 exhibited results similar to those of MCF-7. Our findings indicate that eugenol toxicity is non-apoptotic Bcl-2 independent, affecting mitochondrial function and plasma membrane integrity with no effect on migration or invasion. We report here the chemo-sensitivity of MCF-7 cells to eugenol, a phytochemical with anticancer potential. PMID:28272477

  13. Effect of survivin siRNA on biological behaviour of breast cancer MCF7 cells

    Institute of Scientific and Technical Information of China (English)

    Hao Wang; Yi-Feng Ye

    2015-01-01

    Objective:To investigate the expression of survivin in breast cancer cell lines and explore the effect of survivin siRNA on biology behavior of breast cancer cells.Methods: Western blot was performed to detect the expression of survivin in breast cancer cell lines. Eukaryotic expression vector pIRES2-EGFP-Survivin siRNA was constructed and transfected in MCF7 cells with liposome, the efficiency of survivin siRNA was measured by Western blot and RT-PCR. Cell proliferation and apoptosis were detected by CCK8 and cell flow respectively. Cell migration and invasion was measured by transwell assay.Results: Survivin was highly expressed in MCF-7. Green fluorescence was found in MCF-7 cells tranfected with survivin siRNA and control siRNA by inverted fluorescence microscopy, the protein and mRNA level of survivin was significantly lower in cells tranfected with survivin siRNA compared with control group. Compared with control group, interfering the expression of survivin by siRNA significantly decreased the proliferation, migration and invasion of MCF-7 cells, the percentage of apoptosis cells was greatly promoted.Conclusions: Interfering the expression of Survivin can inhibit the cell proliferation, migration and invasion, and promot apoptosis in MCF-7.

  14. Quercetin Suppresses Twist to Induce Apoptosis in MCF-7 Breast Cancer Cells.

    Directory of Open Access Journals (Sweden)

    Santhalakshmi Ranganathan

    Full Text Available Quercetin is a dietary flavonoid which exerts anti-oxidant, anti-inflammatory and anti-cancer properties. In this study, we investigated the anti-proliferative effect of quercetin in two breast cancer cell lines (MCF-7 and MDA-MB-231, which differed in hormone receptor. IC50 value (37μM of quercetin showed significant cytotoxicity in MCF-7 cells, which was not observed in MDA-MB-231 cells even at 100μM of quercetin treatment. To study the response of cancer cells to quercetin, with respect to different hormone receptors, both the cell lines were treated with a fixed concentration (40μM of quercetin. MCF-7 cells on quercetin treatment showed more apoptotic cells with G1 phase arrest. In addition, quercetin effectively suppressed the expression of CyclinD1, p21, Twist and phospho p38MAPK, which was not observed in MDA-MB-231 cells. To analyse the molecular mechanism of quercetin in exerting an apoptotic effect in MCF-7 cells, Twist was over-expressed and the molecular changes were observed after quercetin administration. Quercetin effectively regulated the expression of Twist, in turn p16 and p21 which induced apoptosis in MCF-7 cells. In conclusion, quercetin induces apoptosis in breast cancer cells through suppression of Twist via p38MAPK pathway.

  15. GENISTEIN INHIBITS EXPRESSION OF VASCULAR ENDOTHELIAL GROWTH FACTOR IN HER-2/NEU TRANSFECTED HUMAN BREAST CANCER MCF-7 CELLS

    Institute of Scientific and Technical Information of China (English)

    ZHU Jun-dong; YU Xiao-ping; MI Man-tian

    2006-01-01

    Objective: our previous studies have demonstrated that HER-2/neu gene expression in human breast cancer MCF-7 cells promotes angiogenesis in MCF-7 cells xenograft tumors, and genistein inhibits angiogenesis in MCF-7 cells with HER-2/neu expression xenograft tumors. Here, the effects of genistein on the expression of vascular endothelial growth factor (VEGF) inMCR-7 cells with HER-2/neu expression were further studied for exploring the molecular mechanism of anti-angiogenesis in HER-2/neu-overexpressing breast cancer by genistein. Methods: HER-2/neu-overexpressing MCF-7 cells (MCF-7/HER-2)were established by transfecting HER-2/neu gene into HER-2/neu negative expression breast cancer MCF-7 cells.Immunocytochemical staining, western blot and reverse transcription-polymerase chain reaction (RT-PCR) were adopted to measure the expression of VEGF in MCF-7/HER-2 cells treated by genistein for 24, 48 and 72h. Results: HER-2/neu expression up-regulated VEGF mRNA and protein in MCF-7 cells, genistein decreased VEGF mRNA and protein level in MCF-7/HER-2 cells in a time-dependent manner. Conclusion: These results suggest that VEGF plays an important role in HER-2/neu gene expression promoted antiogenesis in breast cancer and genistein induced down-regulation of the expression of VEGF may be one of the molecular mechanisms of its anti-angiogenesis in HER-2/neu-overexpressing breast cancer.

  16. Terrain Adaptability Mechanism of Large Ruminants’ Feet on the Kinematics View

    Directory of Open Access Journals (Sweden)

    Qun Zhang

    2015-01-01

    Full Text Available Ruminants live in various parts of land. Similar cloven hooves assist ruminants in adapting to different ground environment during locomotion. This paper analyzes the general terrain adaptability of the feet of ruminants using kinematics of the equivalent mechanism model based on screw theory. Cloven hooves could adjust attitude by changing relative positions between two digits in swing phase. This function helps to choose better landing orientation. “Grasping” or “holding” a rock or other object on the ground passively provides extra adhesion force in stance phase. Ruminants could adjust the position of the metacarpophalangeal joint or metatarsophalangeal joint (MTP or MCP with no relative motion between the tip of feet and the ground, which ensures the adhesion and dexterity in stance phase. These functions are derived from an example from chamois’ feet and several assumptions, which are believed to demonstrate the foundation of adaptation of ruminants and ensure a stable and continuous movement.

  17. Terrain Adaptability Mechanism of Large Ruminants' Feet on the Kinematics View.

    Science.gov (United States)

    Zhang, Qun; Ding, Xilun; Xu, Kun

    2015-01-01

    Ruminants live in various parts of land. Similar cloven hooves assist ruminants in adapting to different ground environment during locomotion. This paper analyzes the general terrain adaptability of the feet of ruminants using kinematics of the equivalent mechanism model based on screw theory. Cloven hooves could adjust attitude by changing relative positions between two digits in swing phase. This function helps to choose better landing orientation. "Grasping" or "holding" a rock or other object on the ground passively provides extra adhesion force in stance phase. Ruminants could adjust the position of the metacarpophalangeal joint or metatarsophalangeal joint (MTP or MCP) with no relative motion between the tip of feet and the ground, which ensures the adhesion and dexterity in stance phase. These functions are derived from an example from chamois' feet and several assumptions, which are believed to demonstrate the foundation of adaptation of ruminants and ensure a stable and continuous movement.

  18. Flat feet

    Science.gov (United States)

    ... Geme JW, Schor NF, eds. Nelson Textbook of Pediatrics . 20th ed. Philadelphia, PA: Elsevier; 2016:chap 674. Review Date 3/9/2017 Updated by: C. Benjamin Ma, MD, Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic Surgery, San Francisco, CA. Also reviewed by David ...

  19. Molecular mechanism of proliferation of human breast cancer cell MCF-7 inhibited by ElA gene%ElA抑制乳腺癌MCF-7细胞增殖及其分子机制

    Institute of Scientific and Technical Information of China (English)

    陈嘉; 申良方; 钟美佐; 朱虹; 曾珊

    2008-01-01

    目的:本研究将ElA基因转染HER-2表达阳性的乳腺癌细胞系MCF-7,并研究ElA对MCF-7细胞增殖的抑制作用及其分子机制.方法:利用基因转染技术检测MCF-7细胞中ElA的表达,RT-PCR和Western杂交检测ElA基因对HER-2 mRNA和蛋白表达水平的调控,MTT法检测ElA对MCF-7细胞增殖的押制作用,软琼脂集落法检测ElA对MCF-7细胞集落形成的影响,并利用流式细胞术检测ElA对MCF-7细胞凋亡的调控.结果:MCF-7细胞无内源性的ElA表达,ElA在MCF-7细胞内的表达显著性地降低了细胞中HER-2 mRNA和蛋白表达水平,诱导MCF-7细胞发生凋亡.细胞增殖曲线显示ElA基因显著性抑制MCF-7细胞增殖和细胞集落形成能力.结论:ElA基因能降低人乳腺癌细胞MCF-7的HER-2表达,诱导细胞发生凋亡,从而抑制细胞的增殖和细胞集落形成能力.

  20. Why have not the hairs on the feet of gecko been smaller?

    Science.gov (United States)

    Su, Yewang; He, Shijie; Hwang, Keh-Chih; Ji, Baohua

    2012-10-01

    The nanometer size of the tiny hair is the key to the secret of strong stickiness of gecko's feet, by which the hair can achieve the maximum adhesion strength that is insensitive to the interfacial flaws with substrate surface. But the question why the hairs have not been smaller is not answered yet. In this study, we derived a geometric parameter of the surface structures considering lateral interaction among hairs, which gives a critical size below which these hairs will bunch together and cause failure of the adhesion, suggesting a lower limit of the dimension of hairs on gecko's feet.

  1. A novel aromatic oil compound inhibits microbial overgrowth on feet: a case study

    Directory of Open Access Journals (Sweden)

    Misner Bill D

    2007-07-01

    Full Text Available Abstract Background Athlete's Foot (Tinea pedis is a form of ringworm associated with highly contagious yeast-fungi colonies, although they look like bacteria. Foot bacteria overgrowth produces a harmless pungent odor, however, uncontrolled proliferation of yeast-fungi produces small vesicles, fissures, scaling, and maceration with eroded areas between the toes and the plantar surface of the foot, resulting in intense itching, blisters, and cracking. Painful microbial foot infection may prevent athletic participation. Keeping the feet clean and dry with the toenails trimmed reduces the incidence of skin disease of the feet. Wearing sandals in locker and shower rooms prevents intimate contact with the infecting organisms and alleviates most foot-sensitive infections. Enclosing feet in socks and shoes generates a moisture-rich environment that stimulates overgrowth of pungent both aerobic bacteria and infectious yeast-fungi. Suppression of microbial growth may be accomplished by exposing the feet to air to enhance evaporation to reduce moistures' growth-stimulating effect and is often neglected. There is an association between yeast-fungi overgrowths and disabling foot infections. Potent agents virtually exterminate some microbial growth, but the inevitable presence of infection under the nails predicts future infection. Topical antibiotics present a potent approach with the ideal agent being one that removes moisture producing antibacterial-antifungal activity. Severe infection may require costly prescription drugs, salves, and repeated treatment. Methods A 63-y female volunteered to enclose feet in shoes and socks for 48 hours. Aerobic bacteria and yeast-fungi counts were determined by swab sample incubation technique (1 after 48-hours feet enclosure, (2 after washing feet, and (3 after 8-hours socks-shoes exposure to a aromatic oil powder-compound consisting of arrowroot, baking soda, basil oil, tea tree oil, sage oil, and clove oil. Conclusion

  2. Effects of aluminum hinged shoes on the structure of contracted feet in Thoroughbred yearlings.

    Science.gov (United States)

    Tanaka, Kousuke; Hiraga, Atsushi; Takahashi, Toshiyuki; Kuwano, Atsutoshi; Morrison, Scott Edward

    2015-01-01

    We applied aluminum hinged shoes (AHSs) to the club foot-associated contracted feet of 11 Thoroughbred yearlings to examine the effects of the shoes on the shape of the hoof and third phalanx (P III). After 3 months of AHS use, the size of the affected hooves increased significantly, reaching the approximate size of the healthy contralateral hooves with respect to the maximum lateral width of the foot, the mean ratio of the bearing border width to the coronary band width, and the mean ratio of the solar surface width to the articular surface width. These results suggest that the AHSs corrected the contracted feet in these yearling horses.

  3. Growth inhibition and induction of apoptosis in MCF-7 breast cancer cells by oridonin nanosuspension.

    Science.gov (United States)

    Feng, Fei-Fei; Zhang, Dian-Rui; Tian, Ke-Li; Lou, Hai-Yan; Qi, Xiao-Li; Wang, Yan-Cai; Duan, Cun-Xian; Jia, Le-Jiao; Wang, Fei-Hu; Liu, Yue; Zhang, Qiang

    2011-05-01

    The mechanism for anti-tumor activity of oridonin (ORI) nanosuspension, prepared by the high pressure homogenization method, was studied using MCF-7 human breast carcinoma cells in vitro. MTT assay, observation of morphologic changes, flow cytometric analysis, and western blot analysis indicated that ORI nanosuspension could significantly intensify the in vitro anti-tumor activity to MCF-7 cells, as compared with ORI solution. Furthermore, ORI nanosuspension induced G₂/M stage proliferation arrest and apoptosis in MCF-7 cells depending on its concentration. In addition, western blot analysis indicated that the pro-caspase-3 protein was not cleaved into the activated form and the expression of anti-apoptotic Bcl-2 protein decreased, on the contrary, the expression of pro-apoptotic Bax protein increased in a dose-dependent manner in ORI nanosuspension-treated cells. These observations indicated that the anti-tumor activity of ORI nanosuspension was intensified by cell-cycle arrest and apoptosis induction.

  4. PERFORMANCE EVALUATION OF A LAYERED WSN USING AODV AND MCF PROTOCOLS IN NS-2

    Directory of Open Access Journals (Sweden)

    Apoorva Dasari

    2014-07-01

    Full Text Available In layered networks, reliability is a major concern as link failures at lower layer will have a great impact on network reliability. Failure at a lower layer may lead to multiple failures at the upper layers which deteriorate the network performance. In this paper, the scenario of such a layered wireless sensor network is considered for Ad hoc On-Demand Distance Vector (AODV and Multi Commodity Flow (MCF routing protocols. MCF is developed using polynomial time approximation algorithms for the failure polynomial. Both protocols are compared in terms of different network parameters such as throughput, packet loss and end to end delay. It was shown that the network reliability is better when MCF protocol is used. It was also shown that maximizing the min cut of the layered network maximizes reliability in the terms of successful packet transmission of network. Thetwo routing protocolsare implemented in the scenario of discrete network event simulator NS-2.

  5. The comparison of radiation responses in MCF-7 and HeLa cells

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Mi Young; Jang, Eun Yeong; Ryu, Tae Ho; Chung, Dong-Min; Kim, Jin Hong; Kim, Jin Kyu [Advanced Radiation Technology Institute, Jeongeup (Korea, Republic of)

    2014-11-15

    Activation of this pathway temporarily arrests cells at the G1 or G2 checkpoints of cell cycle, or terminates DNA replication and cell division. The present study was carried out to identify the fate of cells to cope with DNA damage stress. Cellular responses following IR treatment were different depending on the characteristics (origin, organism and genes expressed etc.) of cell line used and extent of genomic injury. p53 expression level was increased in a dose-dependent manner in both cells. IR induced a drastic increase in expression of p21 in MCF-7 compared to that in HeLa cells. Cell cycle analysis using flow cytometry showed a significant accumulation in G2/M phase after treatment of MCF-7 with IR. This study identified that IR-induced cell fates were determined through p53-dependent activation of p21, which resulted in senescence of MCF-7 cells and autophagy of HeLa cells.

  6. Sodium butyrate-induced apoptosis and ultrastructural changes in MCF-7 breast cancer cells.

    Science.gov (United States)

    Wang, Ying; Hu, Peng-Chao; Ma, Yan-Bin; Fan, Rong; Gao, Fang-Fang; Zhang, Jing-Wei; Wei, Lei

    2016-01-01

    This study investigated the effects of sodium butyrate (NaB) on Michigan Cancer Foundation-7 (MCF-7) breast cancer cells and analyzed the relevant mechanism. Here, we demonstrated that a certain concentration of NaB effectively induced MCF-7 cell apoptosis. Cell counting kit-8 (CCK-8) assay was used to detect cell viability and the apoptosis rate. Western blotting was used to detect changes in the Bcl-2 expression level. We observed cell shape changes with microscopy. Immunofluorescence revealed some apoptotic nuclei. Electron microscopy revealed thick nucleoli, chromatin margination, reduced mitochondria, and dramatic vacuoles. Collectively, our findings elucidated the morphological mechanism by which NaB changed the ultrastructure of MCF-7 cells.

  7. Momordica cochinchinensis Aril Extract Induced Apoptosis in Human MCF-7 Breast Cancer Cells.

    Science.gov (United States)

    Petchsak, Phuchong; Sripanidkulchai, Bungorn

    2015-01-01

    Momordica cochinchinensis Spreng (MC) has been used in traditional medicine due to its high carotenoid content. The objective of this study was to investigate mechanisms underlying apoptotic effects of MC on human MCF-7 breast cancer cells. A lycopene-enriched aril extract of MC (AE) showed cytotoxicity and antiestrogenicity to MCF-7 cells. On DAPI staining, AE induced cell shrinkage and chromatin condensation were evident. With flow cytometric analysis, AE increased the percentage of cells in an early apoptosis stage when compared with the control group. RT-PCR analysis showed AE to significantly increase the expression of the proapoptotic bax gene without effect on expression of the anti-apoptotic bcl-2 gene. Moreover, AE enhanced caspase 6, 8 and 9 activity. Taken together, we conclude that AE of MC fruit has anticancer effects on human MCF-7 breast cancer cells by induction of cell apoptosis via both intrinsic and extrinsic pathways of signaling.

  8. Simulated weightlessness alters biological characteristics of human breast cancer cell line MCF-7

    Science.gov (United States)

    Qian, Airong; Zhang, Wei; Xie, Li; Weng, Yuanyuan; Yang, Pengfei; Wang, Zhe; Hu, Lifang; Xu, Huiyun; Tian, Zongcheng; Shang, Peng

    The aim of this study is to investigate the effects of the clinostat-simulated microgravity on MCF-7 cells (a breast cancer cell line) biological characteristics. MCF-7 cells were incubated for 24 h in an incubator and then rotated in a clinostat as a model of simulated microgravity for 24, 48 and 72 h, respectively. The effects of the clinostat-simulated microgravity on MCF-7 cells proliferation, invasion, migration, gelatinase production, adhesion, cell cycle, apoptosis and vinculin expression were detected. The results showed that the clinostat-simulated microgravity affected breast cancer cell invasion, migration, adhesion, cell cycle, cell apoptosis and vinculin expression. These results may explore a new field of vision to study tumor metastasis in future.

  9. A new hypercube variant: Fractal Cubic Network Graph

    Directory of Open Access Journals (Sweden)

    Ali Karci

    2015-03-01

    Full Text Available Hypercube is a popular and more attractive interconnection networks. The attractive properties of hypercube caused the derivation of more variants of hypercube. In this paper, we have proposed two variants of hypercube which was called as “Fractal Cubic Network Graphs”, and we have investigated the Hamiltonian-like properties of Fractal Cubic Network Graphs FCNGr(n. Firstly, Fractal Cubic Network Graphs FCNGr(n are defined by a fractal structure. Further, we show the construction and characteristics analyses of FCNGr(n where r=1 or r=2. Therefore, FCNGr(n is a Hamiltonian graph which is obtained by using Gray Code for r=2 and FCNG1(n is not a Hamiltonian Graph. Furthermore, we have obtained a recursive algorithm which is used to label the nodes of FCNG2(n. Finally, we get routing algorithms on FCNG2(n by utilizing routing algorithms on the hypercubes.

  10. Ferromagnetic Ground States in Face-Centered Cubic Hubbard Clusters

    Science.gov (United States)

    Souza, T. X. R.; Macedo, C. A.

    2016-01-01

    In this study, the ground state energies of face-centered cubic Hubbard clusters are analyzed using the Lanczos method. Examination of the ground state energy as a function of the number of particle per site n showed an energy minimum for face-centered cubic structures. This energy minimum decreased in n with increasing coulombic interaction parameter U. We found that the ground state energy had a minimum at n = 0.6, when U = 3W, where W denotes the non-interacting energy bandwidth and the face-centered cubic structure was ferromagnetic. These results, when compared with the properties of nickel, shows strong similarity with other finite temperature analyses in the literature and supports the Hirsh’s conjecture that the interatomic direct exchange interaction dominates in driving the system into a ferromagnetic phase. PMID:27583653

  11. Superconductivity in cubic noncentrosymmetric PdBiSe Crystal

    Science.gov (United States)

    Joshi, B.; Thamizhavel, A.; Ramakrishnan, S.

    2015-03-01

    Mixing of spin singlet and spin triplet superconducting pairing state is expected in noncentrosymmetric superconductors (NCS) due to the inherent presence of Rashba-type antisymmetric spin-orbit coupling. Unlike low symmetry (tetragonal or monoclinic) NCS, parity is isotropicaly broken in space for cubic NCS and can additionally lead to the coexistence of magnetic and superconducting state under certain conditions. Motivated with such enriched possibility of unconventional superconducting phases in cubic NCS we are reporting successful formation of single crystalline cubic noncentrosymmetric PdBiSe with lattice parameter a = 6.4316 Å and space group P21 3 (space group no. 198) which undergoes to superconducting transition state below 1.8 K as measured by electrical transport and AC susceptibility measurements. Significant strength of Rashba-type antisymmetric spin-orbit coupling can be expected for PdBiSe due to the presence of high Z (atomic number) elements consequently making it potential candidate for unconventional superconductivity.

  12. Cubic interactions of Maxwell-like higher spins

    CERN Document Server

    Francia, Dario; Mkrtchyan, Karapet

    2016-01-01

    We study the cubic vertices for Maxwell-like higher-spins in flat space. Reducibility of their free spectra implies that a single cubic vertex involving any three fields subsumes a number of couplings among different particles of various spins. The resulting vertices do not involve traces of the fields and in this sense are simpler than their Fronsdal counterparts. We propose an extension of both the free theory and of its cubic deformation to a more general class of partially reducible systems, that one can obtain from the original theory upon imposing trace constraints of various orders. The key to our results is a version of the Noether procedure allowing to systematically account for the deformations of the transversality conditions to be imposed on the gauge parameters at the free level.

  13. Extended temperature dependence of elastic constants in cubic crystals.

    Science.gov (United States)

    Telichko, A V; Sorokin, B P

    2015-08-01

    To extend the theory of the temperature dependence of the elastic constants in cubic crystals beyond the second- and third-order elastic constants, the fourth-order elastic constants, as well as the non-linearity in the thermal expansion temperature dependence, have been taken into account. Theoretical results were represented as temperature functions of the effective elastic constants and compared with experimental data for a number of cubic crystals, such as alkali metal halides, and elements gold and silver. The relations obtained give a more accurate description of the experimental temperature dependences of second-order elastic constants for a number of cubic crystals, including deviations from linear behavior. A good agreement between theoretical estimates and experimental data has been observed.

  14. Tetragonal and cubic zirconia multilayered ceramic constructs created by EPD.

    Science.gov (United States)

    Mochales, Carolina; Frank, Stefan; Zehbe, Rolf; Traykova, Tania; Fleckenstein, Christine; Maerten, Anke; Fleck, Claudia; Mueller, Wolf-Dieter

    2013-02-14

    The interest in electrophoretic deposition (EPD) for nanomaterials and ceramics production has widely increased due to the versatility of this technique to effectively combine different materials in unique shapes and structures. We successfully established an EPD layering process with submicrometer sized powders of Y-TZP with different mol percentages of yttrium oxide (3 and 8%) and produced multilayers of alternating tetragonal and cubic phases with a clearly defined interface. The rationale behind the design of these multilayer constructs was to optimize the properties of the final ceramic by combining the high mechanical toughness of the tetragonal phase of zirconia together with the high ionic conductivity of its cubic phase. In this work, a preliminary study of the mechanical properties of these constructs proved the good mechanical integrity of the multilayered constructs obtained as well as crack deflection in the interface between tetragonal and cubic zirconia layers.

  15. Body-centered-cubic Ni and its magnetic properties.

    Science.gov (United States)

    Tian, C S; Qian, D; Wu, D; He, R H; Wu, Y Z; Tang, W X; Yin, L F; Shi, Y S; Dong, G S; Jin, X F; Jiang, X M; Liu, F Q; Qian, H J; Sun, K; Wang, L M; Rossi, G; Qiu, Z Q; Shi, J

    2005-04-08

    The body-centered-cubic (bcc) phase of Ni, which does not exist in nature, has been achieved as a thin film on GaAs(001) at 170 K via molecular beam epitaxy. The bcc Ni is ferromagnetic with a Curie temperature of 456 K and possesses a magnetic moment of 0.52+/-0.08 micro(B)/atom. The cubic magnetocrystalline anisotropy of bcc Ni is determined to be +4.0x10(5) ergs x cm(-3), as opposed to -5.7x10(4) ergs x cm(-3) for the naturally occurring face-centered-cubic (fcc) Ni. This sharp contrast in the magnetic anisotropy is attributed to the different electronic band structures between bcc Ni and fcc Ni, which are determined using angle-resolved photoemission with synchrotron radiation.

  16. Hardness and thermal stability of cubic silicon nitride

    DEFF Research Database (Denmark)

    Jiang, Jianzhong; Kragh, Flemming; Frost, D. J.

    2001-01-01

    The hardness and thermal stability of cubic spinel silicon nitride (c-Si3N4), synthesized under high-pressure and high-temperature conditions, have been studied by microindentation measurements, and x-ray powder diffraction and scanning electron microscopy, respectively The phase at ambient...... temperature has an average hardness of 35.31 GPa, slightly larger than SiO2 stishovite, which is often referred to as the third hardest material after diamond and cubic boron nitride. The cubic phase is stable up to 1673 K in air. At 1873 K, alpha -and beta -Si3N4 phases are observed, indicating a phase...... transformation sequence of c-to-alpha -to-beta -Si3N4 phases....

  17. A smart tumor targeting peptide-drug conjugate, pHLIP-SS-DOX: synthesis and cellular uptake on MCF-7 and MCF-7/Adr cells.

    Science.gov (United States)

    Song, Qin; Chuan, Xingxing; Chen, Binlong; He, Bing; Zhang, Hua; Dai, Wenbing; Wang, Xueqing; Zhang, Qiang

    2016-06-01

    Doxorubicin (DOX) is a potent anticancer drug for the treatment of tumors, but the poor specificity and multi-drug resistance (MDR) on tumor cells have restricted its application. Here, a pH and reduction-responsive peptide-drug conjugate (PDC), pHLIP-SS-DOX, was synthesized to overcome these drawbacks. pH low insertion peptide (pHLIP) is a cell penetrating peptide (CPP) with pH-dependent transmembrane ability. And because of the unique cell membrane insertion pattern, it might reverse the MDR. The cellular uptake study showed that on both drug-sensitive MCF-7 and drug-resistant MCF-7/Adr cells, pHLIP-SS-DOX obviously facilitated the uptake of DOX at pH 6.0 and the uptake level on MCF-7/Adr cells was similar with that on MCF-7 cells, indicating that pHLIP-SS-DOX had the ability to target acidic tumor cells and reverse MDR. In vitro cytotoxicity study mediated by GSH-OEt demonstrated that the cytotoxic effect of pHLIP-SS-DOX was reduction responsive, with obvious cytotoxicity at pH 6.0; while it had poor cytotoxicity at pH 7.4, no matter with or without GSH-OEt pretreatment. This illustrated that pHLIP could deliver DOX into tumor cells with acidic microenvironment specifically and could not deliver drugs into normal cells with neutral microenvironment. In summary, pHLIP-SS-DOX is a promising strategy to target drugs to tumors and provides a possibility to overcome MDR.

  18. Cytotoxicity of methanol extracts of Elaeis guineensis on MCF-7 and Vero cell lines

    Institute of Scientific and Technical Information of China (English)

    Soundararajan Vijayarathna; Sreenivasan Sasidharan

    2012-01-01

    To investigate the cytotoxic effect of Elaeis guineensis methanol extract on MCF-7 and Vero cell. Methods: In vitro cytotoxicity was evaluated in by MTT assay. Cell morphological changes were observed by using light microscope. Results: The MTT assay indicated that methanol extract of the plant exhibited significant cytotoxic effects on MCF-7. Morphological alteration of the cell lines after exposure with Elaeis guineensis extract were observed under phase contrast microscope in the dose dependent manner. Conclusions: The results suggest the probable use of the Elaeis guineensis methanol extract in preparing recipes for cancer-related ailments. Further studies on isolation of metabolites and their in vivo cytotoxicity are under investigation.

  19. A novel MCF-10A line allowing conditional oncogene expression in 3D culture

    Directory of Open Access Journals (Sweden)

    Danke Christina

    2011-07-01

    Full Text Available Introduction Non-transformed mammary epithelial cell lines such as MCF-10A recapitulate epithelial morphogenesis in three-dimensional (3D tissue culture by forming acinar structures. They represent an important tool to characterize the biological properties of oncogenes and to model early carcinogenic events. So far, however, these approaches were restricted to cells with constitutive oncogene expression prior to the set-up of 3D cultures. Although very informative, this experimental setting has precluded the analysis of effects caused by sudden oncoprotein expression or withdrawal in established epithelial cultures. Here, we report the establishment and use of a stable MCF-10A cell line (MCF-10Atet fitted with a novel and improved doxycycline (dox-regulated expression system allowing the conditional expression of any transgene. Methods MCF-10Atet cells were generated by stable transfection with pWHE644, a vector expressing a second generation tetracycline-regulated transactivator and a novel transcriptional silencer. In order to test the properties of this new repressor/activator switch, MCF-10Atet cells were transfected with a second plasmid, pTET-HABRAF-IRES-GFP, which responds to dox treatment with the production of a bi-cistronic transcript encoding hemagglutinin-tagged B-Raf and green fluorescent protein (GFP. This improved conditional expression system was then characterized in detail in terms of its response to various dox concentrations and exposure times. The plasticity of the phenotype provoked by oncogenic B-RafV600E in MCF-10Atet cells was analyzed in 3D cultures by dox exposure and subsequent wash-out. Results MCF-10Atet cells represent a tightly controlled, conditional gene expression system. Using B-RafV600E as a model oncoprotein, we show that its sudden expression in established 3D cultures results in the loss of acinar organization, the induction of an invasive phenotype and hallmarks of epithelial-to-mesenchymal transition

  20. Cytotoxicity of methanol extracts of Elaeis guineensis on MCF-7 and Vero cell lines.

    Science.gov (United States)

    Vijayarathna, Soundararajan; Sasidharan, Sreenivasan

    2012-10-01

    To investigate the cytotoxic effect of Elaeis guineensis methanol extract on MCF-7 and Vero cell. In vitro cytotoxicity was evaluated in by MTT assay. Cell morphological changes were observed by using light microscope. The MTT assay indicated that methanol extract of the plant exhibited significant cytotoxic effects on MCF-7. Morphological alteration of the cell lines after exposure with Elaeis guineensis extract were observed under phase contrast microscope in the dose dependent manner. The results suggest the probable use of the Elaeis guineensis methanol extract in preparing recipes for cancer-related ailments. Further studies on isolation of metabolites and their in vivo cytotoxicity are under investigation.

  1. Critical parameters in the MCF-7 cell proliferation bioassay (E-Screen)

    DEFF Research Database (Denmark)

    Rasmussen, Thomas Høj; Nielsen, Jesper Bo

    2002-01-01

    The MCF-7 cell proliferation bioassay has grown in popularity as a rapid test for detecting potentially oestrogenic compounds. Several MCF-7 cell sublines with different sensitivities to oestrogens are currently used, with maximal proliferation responses ranging from two- to 10-fold above those o...... hormone-free controls. The specificity was characterized by examining the effects of oestradiol-17beta, the anti-oestrogen ICI 182,780, and dieldrin, a recognized xeno-oestrogen. The improved proliferation bioassay will be a useful tool in identifying potential xeno-oestrogens....

  2. Healthy Feet are Happy Feet

    Centers for Disease Control (CDC) Podcasts

    2007-10-05

    This podcast offers tips for people with diabetes on foot care to prevent complications, such as foot ulcers and amputation.  Created: 10/5/2007 by National Diabetes Education Program (NDEP), a joint program of the Centers for Disease Control and Prevention and the National Institutes of Health.   Date Released: 12/2/2007.

  3. Image interpolation by two-dimensional parametric cubic convolution.

    Science.gov (United States)

    Shi, Jiazheng; Reichenbach, Stephen E

    2006-07-01

    Cubic convolution is a popular method for image interpolation. Traditionally, the piecewise-cubic kernel has been derived in one dimension with one parameter and applied to two-dimensional (2-D) images in a separable fashion. However, images typically are statistically nonseparable, which motivates this investigation of nonseparable cubic convolution. This paper derives two new nonseparable, 2-D cubic-convolution kernels. The first kernel, with three parameters (designated 2D-3PCC), is the most general 2-D, piecewise-cubic interpolator defined on [-2, 2] x [-2, 2] with constraints for biaxial symmetry, diagonal (or 90 degrees rotational) symmetry, continuity, and smoothness. The second kernel, with five parameters (designated 2D-5PCC), relaxes the constraint of diagonal symmetry, based on the observation that many images have rotationally asymmetric statistical properties. This paper also develops a closed-form solution for determining the optimal parameter values for parametric cubic-convolution kernels with respect to ensembles of scenes characterized by autocorrelation (or power spectrum). This solution establishes a practical foundation for adaptive interpolation based on local autocorrelation estimates. Quantitative fidelity analyses and visual experiments indicate that these new methods can outperform several popular interpolation methods. An analysis of the error budgets for reconstruction error associated with blurring and aliasing illustrates that the methods improve interpolation fidelity for images with aliased components. For images with little or no aliasing, the methods yield results similar to other popular methods. Both 2D-3PCC and 2D-5PCC are low-order polynomials with small spatial support and so are easy to implement and efficient to apply.

  4. Higher-spin Interactions from CFT: The Complete Cubic Couplings

    CERN Document Server

    Sleight, Charlotte

    2016-01-01

    In this letter we provide a complete holographic reconstruction of the cubic couplings in the minimal bosonic higher-spin theory in AdS$_{d+1}$. For this purpose we also determine the OPE coefficients of all single-trace conserved currents in the $d$-dimensional free scalar $O\\left(N\\right)$ vector model, and compute the tree-level three-point Witten diagram amplitudes for a generic cubic interaction of higher-spin gauge fields in the metric-like formulation.

  5. Classifying Cubic Edge-Transitive Graphs of Order 8

    Indian Academy of Sciences (India)

    Mehdi Alaeiyan; M K Hosseinipoor

    2009-11-01

    A simple undirected graph is said to be semisymmetric if it is regular and edge-transitive but not vertex-transitive. Let be a prime. It was shown by Folkman (J. Combin. Theory 3(1967) 215--232) that a regular edge-transitive graph of order 2 or 22 is necessarily vertex-transitive. In this paper, an extension of his result in the case of cubic graphs is given. It is proved that, every cubic edge-transitive graph of order 8 is symmetric, and then all such graphs are classified.

  6. Possible form of multi-polar interaction in cubic lattice

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, Osamu; Shiina, Ryousuke; Shiba, Hiroyuki

    2003-05-01

    The invariant form of interaction between multi-poles, including the octupole, is studied for the simple cubic (SC), body centered and face centered cubic lattices. The coupling terms can be arranged in a way similar to that of the hopping matrix between the LCAO's. A table for SC by Shiina et al. (J. Phys. Soc. Japan 66 (1997) 1741) is generalized for the general wave number case of the three types of lattice. Recent experimental result of TmTe is thereby analyzed. The development of the ferromagnetic moment below the anti-ferromagnetic transition under the anti-ferro quadrupolar order phase is discussed in this connection.

  7. Possible form of multi-polar interaction in cubic lattice

    Science.gov (United States)

    Sakai, Osamu; Shiina, Ryousuke; Shiba, Hiroyuki

    2003-05-01

    The invariant form of interaction between multi-poles, including the octupole, is studied for the simple cubic (SC), body centered and face centered cubic lattices. The coupling terms can be arranged in a way similar to that of the hopping matrix between the LCAO's. A table for SC by Shiina et al. (J. Phys. Soc. Japan 66 (1997) 1741) is generalized for the general wave number case of the three types of lattice. Recent experimental result of TmTe is thereby analyzed. The development of the ferromagnetic moment below the anti-ferromagnetic transition under the anti-ferro quadrupolar order phase is discussed in this connection.

  8. Counting perfect matchings of cubic graphs in the geometric dual

    CERN Document Server

    Jiménez, Andrea

    2010-01-01

    Lov\\'asz and Plummer conjectured, in the mid 1970's, that every cubic graph G with no cutedge has an exponential in |V(G)| number of perfect matchings. In this work we show that every cubic planar graph G whose geometric dual graph is a stack triangulation has at least 3 times the golden ratio to |V(G)|/72 distinct perfect matchings. Our work builds on a novel approach relating Lov\\'asz and Plummer's conjecture and the number of so called groundstates of the widely studied Ising model from statistical physics.

  9. Elastic interaction of point defects in crystals with cubic symmetry

    Science.gov (United States)

    Kuz'michev, S. V.; Kukushkin, S. A.; Osipov, A. V.

    2013-07-01

    The energy of elastic mechanical interaction between point defects in cubic crystals is analyzed numerically. The finite-element complex ANSYS is used to investigate the character of interaction between point defects depending on their location along the crystallographic directions , , and on the distance from the free boundary of the crystal. The numerical results are compared with the results of analytic computations of the energy of interaction between two point defects in an infinite anisotropic medium with cubic symmetry. The interaction between compressible and incompressible defects of general type is studied. Conditions for onset of elastic attraction between the defects, which leads to general relaxation of the crystal elastic energy, are obtained.

  10. Cubic surfaces and their invariants: Some memories of Raymond Stora

    Directory of Open Access Journals (Sweden)

    Michel Bauer

    2016-11-01

    I then turn to the study of the family of cubic surfaces. They depend on 20 parameters, and the action of the 15 parameter group SL4(C splits the family in orbits depending on 5 parameters. This takes us into the realm of (geometric invariant theory. I review briefly the classical theorems on the structure of the ring of polynomial invariants and illustrate its many facets by looking at a simple example, before turning to the already involved case of cubic surfaces. The invariant ring was described in the 19th century. I show how to retrieve this description via counting/generating functions and character formulae.

  11. Using the MCF10A/MCF10CA1a Breast Cancer Progression Cell Line Model to Investigate the Effect of Active, Mutant Forms of EGFR in Breast Cancer Development and Treatment Using Gefitinib.

    Directory of Open Access Journals (Sweden)

    Darrell C Bessette

    Full Text Available Basal-like and triple negative breast cancer (TNBC share common molecular features, poor prognosis and a propensity for metastasis to the brain. Amplification of epidermal growth factor receptor (EGFR occurs in ~50% of basal-like breast cancer, and mutations in the epidermal growth factor receptor (EGFR have been reported in up to ~ 10% of Asian TNBC patients. In non-small cell lung cancer several different mutations in the EGFR tyrosine kinase domain confer sensitivity to receptor tyrosine kinase inhibitors, but the tumourigenic potential of EGFR mutations in breast cells and their potential for targeted therapy is unknown.Constructs containing wild type, G719S or E746-A750 deletion mutant forms of EGFR were transfected into the MCF10A breast cells and their tumorigenic derivative, MCF10CA1a. The effects of EGFR over-expression and mutation on proliferation, migration, invasion, response to gefitinib, and tumour formation in vivo was investigated. Copy number analysis and whole exome sequencing of the MCF10A and MCF10CA1a cell lines were also performed.Mutant EGFR increased MCF10A and MCF10CA1a proliferation and MCF10A gefitinib sensitivity. The EGFR-E746-A750 deletion increased MCF10CA1a cell migration and invasion, and greatly increased MCF10CA1a xenograft tumour formation and growth. Compared to MCF10A cells, MCF10CA1a cells exhibited large regions of gain on chromosomes 3 and 9, deletion on chromosome 7, and mutations in many genes implicated in cancer.Mutant EGFR enhances the oncogenic properties of MCF10A cell line, and increases sensitivity to gefitinib. Although the addition of EGFR E746-A750 renders the MCF10CA1a cells more tumourigenic in vivo it is not accompanied by increased gefitinib sensitivity, perhaps due to additional mutations, including the PIK3CA H1047R mutation, that the MCF10CA1a cell line has acquired. Screening TNBC/basal-like breast cancer for EGFR mutations may prove useful for directing therapy but, as in non

  12. Foot Placement Modification for a Biped Humanoid Robot with Narrow Feet

    Directory of Open Access Journals (Sweden)

    Kenji Hashimoto

    2014-01-01

    Full Text Available This paper describes a walking stabilization control for a biped humanoid robot with narrow feet. Most humanoid robots have larger feet than human beings to maintain their stability during walking. If robot’s feet are as narrow as humans, it is difficult to realize a stable walk by using conventional stabilization controls. The proposed control modifies a foot placement according to the robot's attitude angle. If a robot tends to fall down, a foot angle is modified about the roll axis so that a swing foot contacts the ground horizontally. And a foot-landing point is also changed laterally to inhibit the robot from falling to the outside. To reduce a foot-landing impact, a virtual compliance control is applied to the vertical axis and the roll and pitch axes of the foot. Verification of the proposed method is conducted through experiments with a biped humanoid robot WABIAN-2R. WABIAN-2R realized a knee-bended walking with 30 mm breadth feet. Moreover, WABIAN-2R mounted on a human-like foot mechanism mimicking a human's foot arch structure realized a stable walking with the knee-stretched, heel-contact, and toe-off motion.

  13. Evaluation of postural stability in patients wit unilateral vestibular hypofunction:effect of feet orientation

    Institute of Scientific and Technical Information of China (English)

    LIU Bo; KONG Wei-Jia; LENG Yang-ming

    2008-01-01

    To investigate effect of feet orientation on the evaluation of the postural stability in patients with unilateral vestibular hypofunction (UVH) by timed standing tests and static posturography (SPG). Methods 65 subjects with UVH and 92 healthy subjects regarded as control group took the posrural stability tests in four different stances including (1) standard Romberg test, (2) feet-apart stance test, (3) tandem and (4) unilateral standing tests. In each stance, the postural stability was measured in both eyes open (EO) and eyes closed(EC) conditions. The average time that subjects kept balance before falling in each test conditions was recorded by stopwatch as the timed result. In addition, the sway velocity (SV) of center of foot pressure in the upright stance during standard Romberg test and feet apart stance, regarded as postural stability, was also recorded as SPG. Results (1) The balance-maintain-ing time of the UVH group in tandem and unilateral standing with EO and EC was decreased (P 0.05). Conclusions The results suggest that the tandem and unilateral stance tests may provide additional information about the upright stance to the SPG measurement in patients with UVH. The effect of feet orientation on SPG measurements should be considered.

  14. DISABILITIES OF HANDS, FEET AND EYES IN NEWLY-DIAGNOSED LEPROSY PATIENTS IN EASTERN NEPAL

    NARCIS (Netherlands)

    SCHIPPER, A; LUBBERS, WJ; HOGEWEG, M; DESOLDENHOFF, R

    1994-01-01

    The objective of the study was to determine the magnitude of hand/feet/eye disabilities in newly diagnosed leprosy patients by examining all newly diagnosed leprosy patients who presented at the Eastern Leprosy Control Project (supported by The Netherlands Leprosy Relief Association), made up of a r

  15. DISABILITIES OF HANDS, FEET AND EYES IN NEWLY-DIAGNOSED LEPROSY PATIENTS IN EASTERN NEPAL

    NARCIS (Netherlands)

    SCHIPPER, A; LUBBERS, WJ; HOGEWEG, M; DESOLDENHOFF, R

    The objective of the study was to determine the magnitude of hand/feet/eye disabilities in newly diagnosed leprosy patients by examining all newly diagnosed leprosy patients who presented at the Eastern Leprosy Control Project (supported by The Netherlands Leprosy Relief Association), made up of a

  16. Case Report: 16-Year-Old Male with Autistic Disorder with Preoccupation with Female Feet

    Science.gov (United States)

    Early, Maureen C.; Erickson, Craig A.; Wink, Logan K.; McDougle, Christopher J.; Scott, Eric L.

    2012-01-01

    This paper highlights clinical challenges faced when diagnosing and then treating an individual presenting to a child and adolescent psychiatry clinic because of unwelcome comments he made to female peers about their feet. Novel use of exposure therapy helped him effectively decrease his comments from 1 to 2 times per month to once every 6 months.…

  17. Effects of lower limb amputation on the mental rotation of feet

    NARCIS (Netherlands)

    Curtze, Carolin; Otten, Bert; Postema, Klaas

    2010-01-01

    What happens to the mental representation of our body when the actual anatomy of our body changes? We asked 18 able-bodied controls, 18 patients with a lower limb amputation and a patient with rotationplasty to perform a laterality judgment task. They were shown illustrations of feet in different or

  18. Dragons with Clay Feet? : Transition, sustainable land use and rural environment in China and Vietnam

    NARCIS (Netherlands)

    Spoor, M.; Heerink, N.; Qu, F.

    2007-01-01

    Dragons with Clay Feet? presents state-of-the-art research on the impact of ongoing and anticipated economic policy and institutional reforms on agricultural development and sustainable rural resource in two East-Asian transition (and developing) economies--China and Vietnam.

  19. Towards surface analysis on diabetic feet soles to predict ulcerations using photometric stereo

    NARCIS (Netherlands)

    Liu, Chanjuan; Heijden, van der Ferdi; Netten, van Jaap J.; Vo-Dinh, Tuan; Mahadevan-Jansen, Anita; Grundfest, Warren

    2012-01-01

    Diabetic foot ulceration is a major complication for patients with diabetes mellitus. Approximately 15% to 25% of patients with Type I and Type II diabetes eventually develop feet ulcers. If not adequately treated, these ulcers may lead to foot infection, and ultimately to total (or partial) lower e

  20. Gross Square Feet Per Student. IssueTrak: A CEFPI Brief on Educational Facility Issues.

    Science.gov (United States)

    Wohlers, Art

    The Council of Educational Facility Planners International regularly provides the recommended number of gross square feet (gsf) per student figures. This report provides revised numbers based on responses from its Design Portfolio winners over the past 5 years. Average national averages of square footage space per student for Canada and the…

  1. Evaluating joint destruction in rheumatoid arthritis : is it necessary to radiograph both hands and feet?

    NARCIS (Netherlands)

    Knevel, R.; Kwok, K. Y.; de Rooy, D. P. C.; Posthumus, M. D.; Huizinga, T. W. J.; Brouwer, E.; van der Helm-van Mil, A. H. M.

    2013-01-01

    Background Radiological damage is an important outcome measure in rheumatoid arthritis (RA), both for research and clinical purposes. Depending on the setting, both hands and feet are radiographed, or only a part of these. It is unknown whether radiographing part of the four extremities gives compar

  2. Dragons with clay feet? Transition, sustainable land use, and rural environment in China and Vietnam

    NARCIS (Netherlands)

    Spoor, M.; Heerink, N.; Qu, F.

    2010-01-01

    Dragons with Clay Feet? presents state-of-the-art research on the impact of ongoing and anticipated economic policy and institutional reforms on agricultural development and sustainable rural resource in two East-Asian transition (and developing) economies--China and Vietnam. The contributions to th

  3. Foot placement modification for a biped humanoid robot with narrow feet.

    Science.gov (United States)

    Hashimoto, Kenji; Hattori, Kentaro; Otani, Takuya; Lim, Hun-Ok; Takanishi, Atsuo

    2014-01-01

    This paper describes a walking stabilization control for a biped humanoid robot with narrow feet. Most humanoid robots have larger feet than human beings to maintain their stability during walking. If robot's feet are as narrow as humans, it is difficult to realize a stable walk by using conventional stabilization controls. The proposed control modifies a foot placement according to the robot's attitude angle. If a robot tends to fall down, a foot angle is modified about the roll axis so that a swing foot contacts the ground horizontally. And a foot-landing point is also changed laterally to inhibit the robot from falling to the outside. To reduce a foot-landing impact, a virtual compliance control is applied to the vertical axis and the roll and pitch axes of the foot. Verification of the proposed method is conducted through experiments with a biped humanoid robot WABIAN-2R. WABIAN-2R realized a knee-bended walking with 30 mm breadth feet. Moreover, WABIAN-2R mounted on a human-like foot mechanism mimicking a human's foot arch structure realized a stable walking with the knee-stretched, heel-contact, and toe-off motion.

  4. Dynamic Characteristics of Prosthetic Feet: A Comparison Between Modal Parameters of Walking, Running and Sprinting Foot

    Science.gov (United States)

    Noroozi, S.; Rahman, A. G. A.; Dupac, M.; Vinney, J. E.

    Current methods of evaluating the performance of Energy Storing and Returning (ESR) prosthesis are subjective and rely on VO2 consumption. Current prosthetic feet are designed for specific applications and the majority are designed for walking and moderate running. These mechanical feet have fixed mechanical and dynamic characteristics. They have to be selected to meet the requirement of the task and any use outside the domain of the task can result in extreme/severe lack of gait symmetry and loss of energy. Poor gait symmetry results is excess consumption of energy, back pain or fatigue. To investigate if a multipurpose foot can be designed to passively adapt to the walking or running condition one must first understand the different dynamics that are involved and are required from the task specific foot. Static tests have shown these feet to have non-linear stiffness, making the prediction of their dynamic response difficult. The most reliable method to test for dynamic characteristics is drop and modal testing. A method approach has been developed as part of this research to test and compare the dynamic characteristics of three different types of foot (natural frequency, mode shapes and damping). This is needed to explore the differences in the responses of these feet that allow one to be used for walking, one to be used for running and one to be used for sprinting with ease.

  5. Is Epenthesis a Means to Optimize Feet? A Reanalysis of the CLPF Database

    Science.gov (United States)

    Taelman, Helena; Gillis, Steven

    2008-01-01

    Fikkert (1994) analyzed a large corpus of Dutch children's early language production, and found that they often add targetless syllables to their words in order to create bisyllabic feet. In this note we point out a methodological problem with that analysis: in an important number of cases, epenthetic vowels occur at places where grammatical…

  6. Metabolic profiling reveals sphingosine-1-phosphate kinase 2 and lyase as key targets of (phyto- estrogen action in the breast cancer cell line MCF-7 and not in MCF-12A.

    Directory of Open Access Journals (Sweden)

    Nadja Engel

    Full Text Available To search for new targets of anticancer therapies using phytoestrogens we performed comparative metabolic profiling of the breast cancer cell line MCF-7 and the non-tumorigenic breast cell line MCF-12A. Application of gas chromatography-mass spectrometry (GC-MS revealed significant differences in the metabolic levels after exposure with 17ß-estradiol, genistein or a composition of phytoestrogens within a native root flax extract. We observed the metabolites 3-(4-hydroxyphenyl-lactic acid, cis-aconitic acid, 11-beta-hydroxy-progesterone, chenodeoxycholic acid and triacontanoic acid with elevated levels due to estrogen action. Particularly highlighted were metabolites of the sphingolipid metabolism. Sphingosine and its dihydro derivate as well as ethanolaminephosphate were significantly altered after exposure with 1 nM 17ß-estradiol in the cell line MCF-7, while MCF-12A was not affected. Treatment with genistein and the flax extract normalized the sphingosine concentrations to the basic levels found in MCF-12A cells. We could further demonstrate that the expression levels of the sphingosine metabolizing enzymes: sphingosine-1-phosphate kinase (Sphk and lyase (S1P lyase were significantly influenced by estrogens as well as phytoestrogens. The isoform Sphk2 was overexpressed in the tumorigenic cell line MCF-7, while S1P lyase was predominantly expressed in the non-tumorigenic cell line MCF-12A. Importantly, in MCF-7 the weak S1P lyase expression could be significantly increased after exposure with 10 µM genistein and 1 µg/ml root flax extract. Here, we present, for the first time, an analysis of metabolic response of phytoestrogens to breast cancer cell lines. The contrasting regulation of sphingolipid enzymes in MCF-7 and MCF-12A render them as preferred targets for future anticancer strategies.

  7. Delineating genetic alterations for tumor progression in the MCF10A series of breast cancer cell lines.

    Directory of Open Access Journals (Sweden)

    Mitsutaka Kadota

    Full Text Available To gain insight into the role of genomic alterations in breast cancer progression, we conducted a comprehensive genetic characterization of a series of four cell lines derived from MCF10A. MCF10A is an immortalized mammary epithelial cell line (MEC; MCF10AT is a premalignant cell line generated from MCF10A by transformation with an activated HRAS gene; MCF10CA1h and MCF10CA1a, both derived from MCF10AT xenografts, form well-differentiated and poorly-differentiated malignant tumors in the xenograft models, respectively. We analyzed DNA copy number variation using the Affymetrix 500 K SNP arrays with the goal of identifying gene-specific amplification and deletion events. In addition to a previously noted deletion in the CDKN2A locus, our studies identified MYC amplification in all four cell lines. Additionally, we found intragenic deletions in several genes, including LRP1B in MCF10CA1h and MCF10CA1a, FHIT and CDH13 in MCF10CA1h, and RUNX1 in MCF10CA1a. We confirmed the deletion of RUNX1 in MCF10CA1a by DNA and RNA analyses, as well as the absence of the RUNX1 protein in that cell line. Furthermore, we found that RUNX1 expression was reduced in high-grade primary breast tumors compared to low/mid-grade tumors. Mutational analysis identified an activating PIK3CA mutation, H1047R, in MCF10CA1h and MCF10CA1a, which correlates with an increase of AKT1 phosphorylation at Ser473 and Thr308. Furthermore, we showed increased expression levels for genes located in the genomic regions with copy number gain. Thus, our genetic analyses have uncovered sequential molecular events that delineate breast tumor progression. These events include CDKN2A deletion and MYC amplification in immortalization, HRAS activation in transformation, PIK3CA activation in the formation of malignant tumors, and RUNX1 deletion associated with poorly-differentiated malignant tumors.

  8. Ethanol extract of Brazilian red propolis induces apoptosis in human breast cancer MCF-7 cells through endoplasmic reticulum stress.

    Science.gov (United States)

    Kamiya, Tetsuro; Nishihara, Hiroko; Hara, Hirokazu; Adachi, Tetsuo

    2012-11-07

    Propolis, a natural product collected from plants by honey bees, is commonly used in folk medicines. Endoplasmic reticulum (ER) stress is known to induce apoptosis through the induction of CCAAT/enhancer-binding protein homologous protein (CHOP). Here, we investigated whether ethanol extracts of propolis and caffeic acid phenethyl ester (CAPE) induce apoptosis, mitochondrial dysfunction, and ER stress in human breast cancer MCF-7 cells and human fibroblasts. Among several ethanol extracts of propolis and CAPE, Brazilian red propolis (BRP) significantly reduced MCF-7 cell viability through the induction of mitochondrial dysfunction, caspase-3 activity, and DNA fragmentation but did not affect those of fibroblasts. Moreover, treatment with BRP significantly induced CHOP expression in MCF-7 cells compared to fibroblasts. Further, pretreatment with a chemical chaperone, 4-phenylbutyric acid, suppressed BRP-triggered MCF-7 cell death. Overall, we revealed that an ethanol extract of BRP induces MCF-7 cell apoptosis through, at least in part, ER stress-related signaling.

  9. Phase diagrams and synthesis of cubic boron nitride

    CERN Document Server

    Turkevich, V Z

    2002-01-01

    On the basis of phase equilibria, the lowest temperatures, T sub m sub i sub n , above which at high pressures cubic boron nitride crystallization from melt solution is allowable in terms of thermodynamics have been found for a number of systems that include boron nitride.

  10. Interaction of dispersed cubic phases with blood components

    DEFF Research Database (Denmark)

    Bode, J C; Kuntsche, Judith; Funari, S S;

    2013-01-01

    The interaction of aqueous nanoparticle dispersions, e.g. based on monoolein/poloxamer 407, with blood components is an important topic concerning especially the parenteral way of administration. Therefore, the influence of human and porcine plasma on dispersed cubic phases was investigated...

  11. Cubic surfaces and their invariants: Some memories of Raymond Stora

    Science.gov (United States)

    Bauer, Michel

    2016-11-01

    Cubic surfaces embedded in complex projective 3-space are a classical illustration of the use of old and new methods in algebraic geometry. Recently, they made their appearance in physics, and in particular aroused the interest of Raymond Stora, to the memory of whom these notes are dedicated, and to whom I'm very much indebted. Each smooth cubic surface has a rich geometric structure, which I review briefly, with emphasis on the 27 lines and the combinatorics of their intersections. Only elementary methods are used, relying on first order perturbation/deformation theory. I then turn to the study of the family of cubic surfaces. They depend on 20 parameters, and the action of the 15 parameter group SL4 (C) splits the family in orbits depending on 5 parameters. This takes us into the realm of (geometric) invariant theory. I review briefly the classical theorems on the structure of the ring of polynomial invariants and illustrate its many facets by looking at a simple example, before turning to the already involved case of cubic surfaces. The invariant ring was described in the 19th century. I show how to retrieve this description via counting/generating functions and character formulae.

  12. Exact solutions for the cubic-quintic nonlinear Schroedinger equation

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Jiamin [Department of Physics, Zhejiang Lishui University, Lishui 323000 (China)]. E-mail: zjm64@163.com; Ma Zhengyi [Department of Physics, Zhejiang Lishui University, Lishui 323000 (China); Institute of Applied Mathematics and Mechanics, Shanghai University, Shanghai 200072 (China)

    2007-08-15

    In this paper, the cubic-quintic nonlinear Schroedinger equation is solved through the extended elliptic sub-equation method. As a consequence, many types of exact travelling wave solutions are obtained which including bell and kink profile solitary wave solutions, triangular periodic wave solutions and singular solutions.

  13. Combinatorics on Words in Symbolic Dynamics: the Antisymmetric Cubic Map

    Institute of Scientific and Technical Information of China (English)

    Wan Ji DAI; Kebo L(U); Jun WANG

    2008-01-01

    This paper is contributed to the combinatorial properties of the periodic kneading words of antisymmetric cubic maps defined on a interval.The least words of given lengths,the adjacency relations on the words of given lengths and the parity-alternative property in some sets of such words are established.

  14. A Unified Approach to Teaching Quadratic and Cubic Equations.

    Science.gov (United States)

    Ward, A. J. B.

    2003-01-01

    Presents a simple method for teaching the algebraic solution of cubic equations via completion of the cube. Shows that this method is readily accepted by students already familiar with completion of the square as a method for quadratic equations. (Author/KHR)

  15. Orientational phase transition in cubic liquid crystals with positional order

    OpenAIRE

    Pokrovsky, V.L.; Saidachmetov, P.A.

    1988-01-01

    An electric field can give rise to a shear deformation of a cubic liquid crystal with long-range positional order fixed by two plates. The critical value of the field does not depend on the size of the system and depends crucially on the orientation.

  16. An effective packing density of binary cubic crystals

    Science.gov (United States)

    Eremin, I. E.; Eremina, V. V.; Sychev, M. S.; Moiseenko, V. G.

    2015-04-01

    The methodology of effective macroscopic calculation of numerical values of internuclear distances in binary crystals of a cubic crystal system is based on the use of coefficients of the structural packing density of the crystal lattice. The possibility of combining the reference data on the main physicochemical parameters of the substance is implemented by synthesis of the corresponding mathematical models.

  17. Trapping of cubic ZnO nanocrystallites at ambient conditions

    DEFF Research Database (Denmark)

    Decremps, F.; Pellicer-Porres, J.; Datchi, F.

    2002-01-01

    Dense powder of nanocrystalline ZnO has been recovered at ambient conditions in the metastable cubic structure after a heat treatment at high pressure (15 GPa and 550 K). Combined x-ray diffraction (XRD) and x-ray absorption spectroscopy (XAS) experiments have been performed to probe both long-ra...

  18. Specific heat of the simple-cubic Ising model

    NARCIS (Netherlands)

    Feng, X.; Blöte, H.W.J.

    2010-01-01

    We provide an expression quantitatively describing the specific heat of the Ising model on the simple-cubic lattice in the critical region. This expression is based on finite-size scaling of numerical results obtained by means of a Monte Carlo method. It agrees satisfactorily with series expansions

  19. Connecting the Dots Parametrically: An Alternative to Cubic Splines.

    Science.gov (United States)

    Hildebrand, Wilbur J.

    1990-01-01

    Discusses a method of cubic splines to determine a curve through a series of points and a second method for obtaining parametric equations for a smooth curve that passes through a sequence of points. Procedures for determining the curves and results of each of the methods are compared. (YP)

  20. Cubic spline approximation techniques for parameter estimation in distributed systems

    Science.gov (United States)

    Banks, H. T.; Crowley, J. M.; Kunisch, K.

    1983-01-01

    Approximation schemes employing cubic splines in the context of a linear semigroup framework are developed for both parabolic and hyperbolic second-order partial differential equation parameter estimation problems. Convergence results are established for problems with linear and nonlinear systems, and a summary of numerical experiments with the techniques proposed is given.

  1. Rheology of cubic particles suspended in a Newtonian fluid.

    Science.gov (United States)

    Cwalina, Colin D; Harrison, Kelsey J; Wagner, Norman J

    2016-05-18

    Many real-world industrial processes involve non-spherical particles suspended in a fluid medium. Knowledge of the flow behavior of these suspensions is essential for optimizing their transport properties and designing processing equipment. In the present work, we explore and report on the rheology of concentrated suspensions of cubic-shaped colloidal particles under steady and dynamic shear flow. These suspensions exhibit a rich non-Newtonian rheology that includes shear thickening and normal stress differences at high shear stresses. Scalings are proposed to connect the material properties of these suspensions of cubic particle to those measured for suspensions of spherical particles. Negative first normal stress differences indicate that lubrication hydrodynamic forces dominate the stress in the shear-thickened state. Accounting for the increased lubrication hydrodynamic interactions between the flat surfaces of the cubic particles allows for a quantitative comparison of the deviatoric stress in the shear-thickened state to that of spherical particles. New semi-empirical models for the viscosity and normal stress difference coefficients are presented for the shear-thickened state. The results of this study indicate that cubic particles offer new and unique opportunities to formulate colloidal dispersions for field-responsive materials.

  2. Infinite Face Centered Cubic Network of Identical Resistors

    CERN Document Server

    Asad, J H

    2012-01-01

    The equivalent resistance between the origin and any other lattice site, in an infinite Face Centered Cubic network consisting from identical resistors, has been expressed rationally in terms of the known value and . The asymptotic behavior is investigated, and some calculated values for the equivalent resistance are presented.

  3. Trace spaces in a pre-cubical complex

    DEFF Research Database (Denmark)

    Raussen, Martin

    In directed algebraic topology, (spaces of) directed irreversible (d)-paths are studied from a topological and from a categorical point of view. Motivated by models for concurrent computation, we study in this paper spaces of d-paths in a pre-cubical complex. Such paths are equipped with a natural...

  4. Morphosynthesis of cubic silver cages on monolithic activated carbon.

    Science.gov (United States)

    Wang, Fei; Zhao, Hong; Lai, Yijian; Liu, Siyu; Zhao, Binyuan; Ning, Yuesheng; Hu, Xiaobin

    2013-11-14

    Cubic silver cages were prepared on monolithic activated carbon (MAC) pre-absorbed with Cl(-), SO4(2-), or PO4(3-) anions. Silver insoluble salts served as templates for the morphosynthesis of silver cages. The silver ions were reduced by reductive functional groups on MAC micropores through a galvanic cell reaction mechanism.

  5. SUPERCONVERGENCE ANALYSIS FOR CUBIC TRIANGULAR ELEMENT OF THE FINITE ELEMENT

    Institute of Scientific and Technical Information of China (English)

    Qi-ding Zhu

    2000-01-01

    In this paper, we construct a projection interpolation for cubic triangular ele- ment by using othogonal expansion triangular method. We show two fundamental formulas of estimation on a special partion and obtain a superconvergence result of 1 -e order higher for the placement function and its tangential derivative on the third order Lobatto points and Gauss points on each edge of triangular element.

  6. Integrability of Lotka-Volterra Planar Complex Cubic Systems

    Science.gov (United States)

    Dukarić, Maša; Giné, Jaume

    In this paper, we study the Lotka-Volterra complex cubic systems. We obtain necessary conditions of integrability for these systems with some restriction on the parameters. The sufficiency is proved for all conditions, except one which remains open, using different methods.

  7. Global Well-Posedness for Cubic NLS with Nonlinear Damping

    KAUST Repository

    Antonelli, Paolo

    2010-11-04

    We study the Cauchy problem for the cubic nonlinear Schrödinger equation, perturbed by (higher order) dissipative nonlinearities. We prove global in-time existence of solutions for general initial data in the energy space. In particular we treat the energy-critical case of a quintic dissipation in three space dimensions. © Taylor & Francis Group, LLC.

  8. Optical coherence tomography detection of shear wave propagation in MCF7 cell modules

    Science.gov (United States)

    Razani, Marjan; Mariampillai, Adrian; Berndl, Elizabeth S. L.; Kiehl, Tim-Rasmus; Yang, Victor X. D.; Kolios, Michael C.

    2014-02-01

    In this work, we explored the potential of measuring shear wave propagation using Optical Coherence Elastography (OCE) in MCF7 cell modules (comprised of MCF7 cells and collagen) and based on a swept-source optical coherence tomography (OCT) system. Shear waves were generated using a piezoelectric transducer transmitting sine-wave bursts of 400 μs, synchronized with an OCT swept source wavelength sweep imaging system. Acoustic radiation force was applied to the MCF7 cell constructs. Differential OCT phase maps, measured with and without the acoustic radiation force, demonstrate microscopic displacement generated by shear wave propagation in these modules. The OCT phase maps are acquired with a swept-source OCT (SS-OCT) system. We also calculated the tissue mechanical properties based on the propagating shear waves in the MCF7 + collagen phantoms using the Acoustic Radiation Force (ARF) of an ultrasound transducer, and measured the shear wave speed with the OCT phase maps. This method lays the foundation for future studies of mechanical property measurements of breast cancer structures, with applications in the study of breast cancer pathologies.

  9. Inhibitory effects and molecular mechanisms of tetrahydrocurcumin against human breast cancer MCF-7 cells

    Directory of Open Access Journals (Sweden)

    Xiao Han

    2016-02-01

    Full Text Available Background: Tetrahydrocurcumin (THC, an active metabolite of curcumin, has been reported to have similar biological effects to curcumin, but the mechanism of the antitumor activity of THC is still unclear. Methods: The present study was to investigate the antitumor effects and mechanism of THC in human breast cancer MCF-7 cells using the methods of MTT assay, LDH assay, flow cytometry analysis, and western blot assay. Results: THC was found to have markedly cytotoxic effect and antiproliferative activity against MCF-7 cells in a dose-dependent manner with the IC50 for 24 h of 107.8 μM. Flow cytometry analysis revealed that THC mediated the cell-cycle arrest at G0/G1 phase, and 32.8% of MCF-7 cells entered the early phase of apoptosis at 100 μM for 24 h. THC also dose-dependently led to apoptosis in MCF-7 cells via the mitochondrial pathway, as evidenced by the activation of caspase-3 and caspase-9, the elevation of intracellular ROS, a decrease in Bcl-2 and PARP expression, and an increase in Bax expression. Meanwhile, cytochrome C was released to cytosol and the loss of mitochondria membrane potential (Δψm was observed after THC treatment. Conclusion: THC is an excellent source of chemopreventive agents in the treatment of breast cancer and has excellent potential to be explored as antitumor precursor compound.

  10. Translational control of TWIST1 expression in MCF-10A cell lines recapitulating breast cancer progression

    DEFF Research Database (Denmark)

    Nairismägi, Maarja-Liisa; Vislovukh, Andrii; Meng, Q

    2012-01-01

    TWIST1 is a highly conserved basic helix-loop-helix transcription factor that promotes epithelial–mesenchymal transition (EMT). Its misregulation has been observed in various types of tumors. Using the MCF-10A-series of cell lines that recapitulate the early stages of breast cancer formation...

  11. Electrochemical estrogen screen method based on the electrochemical behavior of MCF-7 cells.

    Science.gov (United States)

    Li, Jinlian; Song, Jia; Bi, Sheng; Zhou, Shi; Cui, Jiwen; Liu, Jiguang; Wu, Dongmei

    2016-08-05

    It was an urgent task to develop quick, cheap and accurate estrogen screen method for evaluating the estrogen effect of the booming chemicals. In this study, the voltammetric behavior between the estrogen-free and normal fragmented MCF-7 cell suspensions were compared, and the electrochemical signal (about 0.68V attributed by xanthine and guanine) of the estrogen-free fragmented MCF-7 cell suspension was obviously lower than that of the normal one. The electrochemistry detection of ex-secretion purines showed that the ability of ex-secretion purines of cells sharp decreased due to the removing of endogenous estrogen. The results indicated that the electrochemical signal of MCF-7 cells was related to the level of intracellular estrogen. When the level of intracellular estrogen was down-regulated, the concentrations of the xanthine and hypoxanthine decreased, which led to the electrochemical signal of MCF-7 cells fall. Based on the electrochemical signal, the electrochemical estrogen screen method was established. The estrogen effect of estradiol, nonylphenol and bisphenol A was evaluated with the electrochemical method, and the result was accordant with that of MTT assay. The electrochemical estrogen screen method was simple, quickly, cheap, objective, and it exploits a new way for the evaluation of estrogenic effects of chemicals.

  12. Assessing oestrogenic effects of brominated flame retardants hexabromocyclododecane and tetrabromobisphenol A on MCF-7 cells.

    Science.gov (United States)

    Dorosh, A; Děd, L; Elzeinová, F; Pěknicová, J

    2011-01-01

    Tetrabromobisphenol A (TBBPA) is the main flame retardant used in printed circuit boards and laminates. The human population is highly exposed to TBBPA as it is used in consumer electronics as well as office and communication equipment. The main use of hexabromocyclododecane (HBCD) is in insulation foam boards, which are widely used in the construction sector. Brominated flame retardants may possess endocrine disrupting activity and thus represent a threat to the environment, including humans and their reproduction. The aim of this work was to evaluate the oestrogenic effects of TBBPA and HBCD in vitro on MCF-7 cells. We used the proliferation test (E-screen assay) in MCF-7 breast cancer cells and reverse transcription quantitative polymerase chain reaction analysis of TFF1 gene expression to analyse oestrogenicity of the studied compounds. RT-qPCR has proved to be a fast and valuable molecular technique in gene expression quantification. HBCD but not TBBPA increased cell proliferation in MCF-7 cells and up-regulated TFF1 gene expression in a concentration-dependent manner. Anti-oestrogen ICI 182,780 inhibited up-regulation of TFF1 by HBCD. We have shown that HBCD displays oestrogen- like effects on MCF-7 cells. TBBPA, on the other hand, has not shown any oestrogenic effect mediated by the oestrogen receptor α.

  13. The Signaling Cascades of Ginkgolide B-Induced Apoptosis in MCF-7 Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Wen-Hsiung Chan

    2007-11-01

    Full Text Available Ginkgolide B, the major active component of Ginkgo biloba extracts, can bothstimulate and inhibit apoptotic signaling. Here, we demonstrate that ginkgolide B caninduce the production of reactive oxygen species in MCF-7 breast cancer cells, leading toan increase in the intracellular concentrations of cytoplasmic free Ca2+ and nitric oxide(NO, loss of mitochondrial membrane potential (MMP, activation of caspase-9 and -3,and increase the mRNA expression levels of p53 and p21, which are known to be involvedin apoptotic signaling. In addition, prevention of ROS generation by pretreatment withN-acetyl cysteine (NAC could effectively block intracellular Ca2+ concentrationsincreases and apoptosis in ginkgolide B-treated MCF-7 cells. Moreover, pretreatment withnitric oxide (NO scavengers could inhibit ginkgolide B-induced MMP change andsequent apoptotic processes. Overall, our results signify that both ROS and NO playedimportant roles in ginkgolide B-induced apoptosis of MCF-7 cells. Based on these studyresults, we propose a model for ginkgolide B-induced cell apoptosis signaling cascades inMCF-7 cells.

  14. Milk fat conjugated linoleic acid (CLA) inhibits growth of human mammary MCF-7 cancer cells.

    Science.gov (United States)

    O'Shea, M; Devery, R; Lawless, F; Murphy, J; Stanton, C

    The relationship between growth and the antioxidant enzyme defence system in human MCF-7 (breast) cancer cells treated with bovine milk fat enriched with conjugated linoleic acid (CLA) was studied. Milk enriched in CLA was obtained from cows on pasture supplemented with full fat rapeseeds and full fat soyabeans (1). Cell number decreased up to 90% (p milk fat yielding CLA concentrations between 16.9 and 22.6 ppm. Growth suppression and prooxidant effects of milk fat CLA were independent of the variable composition of the milk fat samples, suggesting that CLA was the active ingredient in milk fat responsible for the cytotoxic effect. Mixtures containing isomers of CLA (c9, t11-, t10, c12-, c11, t13- and minor amounts of other isomers) and linoleic acid (LA) at similar concentrations to the milk fat samples were as effective at inhibiting growth and stimulating peroxidation of MCF-7 cells as the milk fatty acids. Incubation of the cells with the c9, t11 CLA isomer (20 ppm) or the mixture of CLA isomers (20 ppm) for 8 days resulted in a 60% decrease (p milk fat than the c9, t11 synthetic CLA isomer. Superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx) activities were induced in MCF-7 cells exposed to milk fat (containing 16.9-22.6 ppm CLA) over 8 days. The data indicate that milk fat triglyceride-bound CLA, consisting primarily of the c9, t11 isomer, was cytotoxic towards MCF-7 cells.

  15. Overexpress of CD47 does not alter the stemness of MCF-7 breast cancer cells

    Directory of Open Access Journals (Sweden)

    Oanh Thi-Kieu Nguyen

    2016-09-01

    Full Text Available Background: CD47 is a transmembrane glycoprotein expressed on all cells in the body and particularly overexpressed on cancer cells and cancer stem cells of both hematologic and solid malignancies. In the immune system, CD47 acts as a and ldquo;don't eat me and rdquo; signal, inhibiting phagocytosis by macrophages by interaction with signal regulatory protein and #945; (SIRP and #945;. In cancer, CD47 promotes tumor invasion and metastasis. This study aimed to evaluate the stemness of breast cancer cells when CD47 is overexpressed. Methods: MCF-7 breast cancer cells were transfected with plasmid pcDNA3.4-CD47 containing the CD47 gene. The stemness of the transduced MCF7 cell population was evaluated by expression of CD44 and CD24 markers, anti-tumor drug resistance and mammosphere formation. Results: Transfection of plasmid pcDNA3.4-CD47 significantly increased the expression of CD47 in MCF-7 cells. The overexpression of CD47 in transfected MCF-7 cells led to a significant increase in the CD44+CD24- population, but did not increase doxorubicin resistance of the cells or their capacity to form mammospheres. Conclusion: CD47 overexpression enhances the CD44+CD24- phenotype of breast cancer cells as observed by an increase in the CD44+CD24- expressing population. However, these changes are insufficient to increase the stemness of breast cancer cells. [Biomed Res Ther 2016; 3(9.000: 826-835

  16. TNF-alpha-induced metastasis gene changes in MCF-7 cells

    Institute of Scientific and Technical Information of China (English)

    Xiaofeng Chen; Yongqian Shu; Wei Li; Yongmei Yin

    2008-01-01

    Objective: Studies have shown that TNF- a secreted by tumor cells and macrophages infiltrated into the tumor microenvironment might promote the metastasis of a variety of malignant cancers, including breast cancer. The present study was designed to detect global metastasis-related gene expression changes of MCF-7 cells treated by low dose TNF-a and to further explore the mechanisms by which TNF-a contributes to metastasis. Methods: MCF-7 cells were cultured and treated with low dose TNF-a (20 ng/ml), cDNA array analysis was applied to detect the metastasis related gene expressions. Results: A total of 36 gene expressions were significantly regulated by TNF-a. Functional analysis indicates that the altered genes belong to different functional group. Most of the genes changed may promote the metastasis of MCF-7 cells while the others may inhibit metastasis. The changes observed in gene expression following TNF-a were somewhat time dependent. Conclusion: TNF-a can enhance the invasive ability of MCF-7 cells, partly by regulating a series of metastasis related genes, and these genes may take part in every step of metastasis. Some of the genes deserve further study.

  17. Downregulation of SOK1 promotes the migration of MCF-7 cells

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Xu-Dong, E-mail: xudongchen305@hotmail.com [Key Lab of Molecular Medicine, Ministry of Education, Shanghai Medical College, Fudan University, Shanghai (China); Cho, Chien-Yu [Department of Biochemistry, College of Medicine, National Cheng Kung University, Taiwan (China)

    2011-04-08

    Highlights: {yields} SOK1 is a member of GCK-III subfamily. It is activated by oxidative stress or chemical anoxia. {yields} Barr's group have found that autophosphorylation of SOK1 is triggered by binding to the Golgi matrix protein GM130 and made the cells migration through dimeric adaptor protein 14-3-3. {yields} But what we found is that downregulation of SOK1 promotes cell migration and leads to the upregulation of GM130 and Tyr861 of FAK in MCF-7 cells. -- Abstract: SOK1 is a member of the germinal center kinase (GCK-III) subfamily but little is known about it, particularly with respect to its role in signal transduction pathways relative to tumor metastasis. By stably transfecting SOK1 siRNA into the MCF-7 breast cancer cell line we found that SOK1 promotes the migration of MCF-7 cells, as determined using wound-healing and Boyden chamber assays. However, cell proliferation assays revealed that silencing SOK1 had no effect on cell growth relative to the normal cells. Silencing SOK1 also had an effect on the expression and phosphorylation status of a number of proteins in MCF-7 cells, including FAK and GM130, whereby a decrease in SOK1 led to an increase in the expression of these proteins.

  18. PNIPAAm-MAA nanoparticles as delivery vehicles for curcumin against MCF-7 breast cancer cells.

    Science.gov (United States)

    Zeighamian, Vahideh; Darabi, Masoud; Akbarzadeh, Abolfazl; Rahmati-Yamchi, Mohammad; Zarghami, Nosratollah; Badrzadeh, Fariba; Salehi, Roya; Mirakabad, Fatemeh Sadat Tabatabaei; Taheri-Anganeh, Mortaza

    2016-01-01

    Breast cancer is the most frequently occurring cancer among women throughout the world. Natural compounds such as curcumin hold promise to treat a variety of cancers including breast cancer. However, curcumin's therapeutic application is limited, due to its rapid degradation and poor aqueous solubility. On the other hand, previous studies have stated that drug delivery using nanoparticles might improve the therapeutic response to anticancer drugs. Poly(N-isopropylacrylamide-co-methacrylic acid) (PNIPAAm-MAA) is one of the hydrogel copolymers utilized in the drug delivery system for cancer therapy. The aim of this study was to examine the cytotoxic potential of curcumin encapsulated within the NIPAAm-MAA nanoparticle, on the MCF-7 breast cancer cell line. In this work, polymeric nanoparticles were synthesized through the free radical mechanism, and curcumin was encapsulated into NIPAAm-MAA nanoparticles. Then, the cytotoxic effect of curcumin-loaded NIPAAm-MAA on the MCF-7 breast cancer cell line was measured by MTT assays. The evaluation of the results showed that curcumin-loaded NIPAAm-MAA has more cytotoxic effect on the MCF-7 cell line and efficiently inhibited the growth of the breast cancer cell population, compared with free curcumin. In conclusion, this study indicates that curcumin-loaded NIPAAm-MAA suppresses the growth of the MCF-7 cell line. Overall, it is concluded that encapsulating curcumin into the NIPAAm-MAA copolymer could open up new avenues for breast cancer treatment.

  19. Expression and inducibility of UDP-glucuronosyltransferase 1As in MCF-7 human breast carcinoma cells.

    Science.gov (United States)

    Hanioka, Nobumitsu; Iwabu, Hiroyuki; Hanafusa, Hiroyuki; Nakada, Shintaro; Narimatsu, Shizuo

    2012-03-01

    UDP-glucuronosyltransferases (UGTs) are conjugation enzymes, which are regulated in a tissue-specific manner by endogenous and environmental factors. In this study, we focused on UGT1A isoforms broadly expressed in hepatic and extrahepatic tissues and examined the expression and inducibility of UGT1As (UGT1A1 and UGT1A3-1A10) in MCF-7 cells (human breast carcinoma cell line). Reverse transcription polymerase chain reaction (RT-PCR) analysis demonstrated that UGT1A1, UGT1A6 and UGT1A9 mRNAs as well as the mRNAs of transcriptional regulators (AhR, aryl hydrocarbon receptor; Arnt, AhR nuclear translocator; ERα, oestrogen receptor α; ERβ, oestrogen receptor β; and GR, glucocorticoid receptor) are expressed in MCF-7 cells. UGT1A6 mRNA level in MCF-7 cells was significantly increased to 1.9 times by β-naphthoflavone (BNF), whereas UGT1A1 and UGT1A9 mRNA levels were not affected by BNF. There were no significant changes in the mRNAs of UGT1A1, UGT1A6 and UGT1A9 in MCF-7 cells by treatment with phenobarbital (PB) and dexamethasone (DEX) in MCF-7 cells. The kinetics of 7-ethyl-10-hydroxycamptothecin (SN-38), 5-hydroxytryptamine (5-HT) and 4-methylumbelliferone (4-MU) glucuronidation by microsomes from control and BNF-treated MCF-7 cells fitted with the Michaelis-Menten model, and the V(max) and CL(int) values were significantly increased to 7.5-8.5 times and 5.9-10.4 times by BNF treatment, respectively. These findings suggest that BNF induces UGT1A6 in MCF-7 cells and that the increase may be mediated by AhR but not pregnane X receptor (PXR)/constitutive androstane receptor (CAR). The information gained in this study should help predict and assess the toxicity of environmental chemicals.

  20. An investigation on cytotoxic effect of bioactive AgNPs synthesized using Cassia fistula flower extract on breast cancer cell MCF-7

    Directory of Open Access Journals (Sweden)

    R.R. Remya

    2015-12-01

    Full Text Available A single step protocol to produce biofunctionalized silver nanoparticles (AgNPs using the aqueous extract of Cassia fistula flower as “natural factory” was investigated. The reaction between silver ions and aqueous flower extract after the bioreduction process has resulted in the formation of reddish brown color colloidal solution. XRD pattern showed the face centered cubic crystalline structure of AgNPs and exhibited spherical morphology as characterized by FE-SEM. FTIR studies identified different functional groups involved in effective capping of AgNPs. The zeta potential affirmed the phytoreduced AgNPs possess good stability and the size of the particle was measured by DLS. The synthesized AgNPs displayed effective cytotoxic potential against MCF7 and the inhibitory concentration (IC50 was recorded at 7.19 μg/mL. The apoptotic effects of the AgNPs were also confirmed by AO/EB staining. The investigation presents preliminary evidence that biosynthesized AgNPs can be used in the development of novel anticancer drugs.

  1. A comparative study of 5-Fluorouracil release from chitosan/silver and chitosan/silver/MWCNT nanocomposites and their cytotoxicity towards MCF-7.

    Science.gov (United States)

    E A K, Nivethaa; S, Dhanavel; A, Rebekah; V, Narayanan; A, Stephen

    2016-09-01

    5-Fluorouracil encapsulated chitosan/silver and chitosan/silver/multiwalled carbon nanotubes were synthesized to comparatively study the release profile and cytotoxicity of the systems towards MCF-7 cell line. The triclinic structure of 5-Fluorouracil, face centered cubic structure of silver and the semi-crystalline nature of chitosan were elucidated using the XRD pattern. The XRD pattern of Chitosan/silver/multiwalled carbon nanotube consisted of (002) reflection of graphitic carbon from carbon nanotube. The evident splitting of NH2 and NH3(+) and a variation in the intensity of OH peaks in the FTIR pattern were indicative of the binding of moieties like silver, carbon nanotube and 5-Fluorouracil to chitosan. The encapsulation of 5-Fluorouracil was evident from elemental mapping and from the presence of reflections corresponding to 5-Fluorouracil in the SAED pattern. The release profile showed a prolonged release for 5-Fluorouracil encapsulated Chitosan/silver/multiwalled carbon nanotube and a better cytotoxicity with a IC50 of 50μg/ml was observed for the same.

  2. A STUDY ON PREVALENCE OF FLAT FEET AMONG SCHOOL CHILDREN IN KANCHIPURAM POPULATION

    Directory of Open Access Journals (Sweden)

    D.Krupa Daniel

    2015-09-01

    Full Text Available Background: A flexible flatfoot is considered to be a variation of a normal foot. Any deviation from the anatomical plantigrade foot is a deformed foot. Some of the deformities of the foot are: Flat Foot. The normal concavity due to the medial longitudinal arch is absent. High Arch Foot - A normal foot has a medial longitudinal arch which is higher. Materials and Methods: A total population of 625, in age ranging from 5 year to 9 years in Kanchipuram district was chosen. Each individual was made to sit and the foot was brought in contact with the Foot Impression gaining Kit on white sheets in standing posture. Results: The flat feet and high arch feet evaluation was obtained by means of foot prints and the plantar arch index was established. The mean values of plantar arch index within the age group were stable and ranges from 0.72 to 0.73. With plantar arch indices greater than 1.15 was regarded as flatfeet and less than 0.10 was regarded as High arch feet. Discussion: In normal feet with presence of an arch, the stress will be distributed in an even manner so that the person will not experience any kind of pain. Under an abnormal condition that occurs due to lack of stretching of muscles, bones and tendons, there will be absence of arch among these people. In this condition, all the weight will be concentrated in smaller area on the feet and generates a lot more pain than normal. This condition might occur in both children and adults. In some people both feet will be flat and in some only one foot will be flat. Conclusion: Flat foot is highly prevalent in the ages between 5-9. The average values for plantar arch indices are stable and ranges from 0.72 to 0.73 in our sample regarded as Normal foot. Plantar arch index > 1.15 is regarded as Flat foot. Plantar arch index < 0.10 is regarded as High arch foot.

  3. Human adipocytes stimulate invasion of breast cancer MCF-7 cells by secreting IGFBP-2.

    Directory of Open Access Journals (Sweden)

    Chen Wang

    Full Text Available A better understanding of the effects of human adipocytes on breast cancer cells may lead to the development of new treatment strategies. We explored the effects of adipocytes on the migration and invasion of breast cancer cells both in vitro and in vivo.To study the reciprocal effects of adipocytes and cancer cells, we co-cultured human mature adipocytes and breast cancer cells in a system devoid of heterogeneous cell-cell contact. To analyze the factors that were secreted from adipocytes and that affected the invasive abilities of breast cancer cells, we detected different cytokines in various co-culture media. To study the communication of mature adipocytes and breast cancer cells in vivo, we chose 10 metastatic pathologic samples and 10 non-metastatic pathologic samples to do immunostaining.The co-culture media of human MCF-7 breast cancer cells and human mature adipocytes increased motility of MCF-7 cells. In addition, MMP-2 was remarkably up-regulated, whereas E-cadherin was down-regulated in these MCF-7 cells. Based on our co-culture medium chip results, we chose four candidate cytokines and tested their influence on metastasis individually. We found that IGFBP-2 enhanced the invasion ability of MCF-7 cells in vitro more prominently than did the other factors. In vivo, metastatic human breast tumors had higher levels of MMP-2 than did non-metastatic tumor tissue, whereas adipocytes around metastatic breast tumors had higher levels of IGFBP-2 than did adipocytes surrounding non-metastatic breast tumors.IGFBP-2 secreted by mature adipocytes plays a key role in promoting the metastatic ability of MCF-7 breast cancer cells.

  4. The Study of Apoptotic Effect of p-Coumaric Acid on Breast Cancer Cells MCF-7

    Directory of Open Access Journals (Sweden)

    M Kolahi

    2016-06-01

    Full Text Available Introduction: Polyphenolic compounds have anti proliferative and induced apoptotic features on cancer cells. p-Coumaric acid can be abundantly found in fruits, vegetables, plant production and honey. .  Breast cancer is the most frequently diagnosed cancer among women in the world. This study aimed to investigate the effect and mechanism of p- coumaric acid on apoptosis of MCF-7 breast cancer cells. Methods: In order to study appoptic effect of p- coumaric acid, MCF-7 breast cancer cells were treated with different concentrations of p- coumaric acid (10, 37, 70, 150 and 300 mM for 24 h. Cell viability was determined using MTT assay. Apoptosis markers including phosphatidylserine exposure at the outer leaflet of the plasma membrane were measured using flow cytometery for Annexin V affinity. Results: Cell viability of MCF-7 cells was decreased with increasing of p- coumaric acid concentration. Maximal effect of p- coumaric acid was observed in cells that treated with 300 mM for 24h (p< 0.05. Viability assay showed that the IC50 of p- coumaric acid in MCF-7 cells was about 40 mM. p- coumaric acid at dose of 300 mM significantly increased the late apoptotic cells with Annexin V+ and propium iodide (PI+ features after 24 h treatment. Conclusion: The results of this study showed that p- coumaric acid had effective appoptic activity against MCF-7 cells. The results can be helpful in understanding the anticancer mechanism of p- coumaric acid and using it was suggested as an alternative or complementary drug in cancer chemotherapy.

  5. Apigenin induced MCF-7 cell apoptosis-associated reactive oxygen species.

    Science.gov (United States)

    Bai, Haihua; Jin, Hua; Yang, Fen; Zhu, Haiyan; Cai, Jiye

    2014-01-01

    Apigenin is a flavonoid, which has been proved to possess effective anti-cancer bioactivities against variety of cell lines. However, little is known about its effect on the cell-surface and the interaction between cell-surface and the reacting drug. In this study, human breast cancer line (MCF-7) was selected to be as a cell model to investigate the effects of apigenin on cell growth, proliferation, apoptosis, cellular morphology, etc. MTT assay showed that the growth inhibition induced by apigenin was in a dose-dependent manner when treated with different concentrations of apigenin while had little cytotoxic effects on human normal cells (MCF-10A). Fluorescence-based flow cytometry was used to detect cellular apoptosis and ROS production. The results showed that 80 µM apigenin could effectively induce apoptosis and overproduction of ROS in MCF-7 cells. Here, atomic force microscopy (AFM) was utilized to detect the shapes and membrane structures of MCF-7 cells at cellular or subcellular level. The results showed that the control MCF-7 cells presented typical elongated-spindle shapes with abundant pseudopodia, while after treated with apigenin, the cells shrunk and became round, the pseudopodia diminished. Moreover, the images of ultrastructure indicated that the cell membrane was composed of nanoparticles of 49 nm, but with the treated concentrations of apigenin increasing, the sizes of membrane particles significantly increased to 400 nm. These results can improve our understanding of apigenin, which can be potentially developed as a new agent for treatment of cancers.

  6. Regulation of MCF-7 breast cancer cell growth by beta-estradiol sulfation.

    Science.gov (United States)

    Falany, Josie L; Macrina, Nancy; Falany, Charles N

    2002-07-01

    Estrogen stimulation is an important factor in human breast cancer cell growth and development. Metabolism of beta-estradiol (E2), the major endogenous human estrogen, is important in regulating both the level and activity of the hormone in breast tissues. Conjugation of E2 with a sulfonate moiety is an inactivation process since the sulfate ester formed by this reaction can not bind and activate the estrogen receptor. In human tissues including the breast, estrogen sulfotransferase (EST, SULT1E1) is responsible for high affinity E2 sulfation activity. EST is expressed in human mammary epithelial (HME) cells but not in most cultured breast cancer cell lines, including estrogen responsive MCF-7 cells. Stable expression of EST in MCF-7 cells at levels similar to those detected in HME cells significantly inhibits cell growth at physiologically relevant E2 concentrations. The mechanism of cell growth inhibition involves the abrogation of responses observed in growth factor expression in MCF-7 cells following E2 stimulation. MCF-7 cells expressing EST activity did not show a decrease in estrogen receptor-alpha levels, nor a characteristic increase in progesterone receptor or decrease in transforming growth factor-beta expression upon exposure to 100 pM or 1 nM E2. The lack of response in these MCF-7 cells is apparently due to the rapid sulfation and inactivation of free E2 by EST. These results suggest that loss of EST expression in the transformation of normal breast tissues to breast cancer may be an important factor in increasing the growth responsiveness of preneoplastic or tumor cells to estrogen stimulation.

  7. Reversal Effect of Silymarin on Drug Resistant Breast CancerCell MCF-7/ADM%水飞蓟素逆转人乳腺癌耐药细胞株MCF-7/ADM耐药性实验研究

    Institute of Scientific and Technical Information of China (English)

    陆一丹; 徐良额; 裘嘉琪; 毛丹漪; 刘晓谷; 王大维

    2016-01-01

    Objective To investigate the effect of silymarin on drug resistance of breast cancer cell line MCF-7/ADM. Methods The toxicant effect of adriamycin to MCF-7/S(sensitive strain) and MCF-7/ADM(drug-resistant strain) was measured by CCK-8 in vitrofor resistant index. Silymarin was screened in advance and the dose of 10μg/ml was nontoxicant to MCF- 7/ADM, then MCF- 7/ADM was treated with this dose of silymarin (10μg/ml) to observe the reversal effect of silymarin. Results IC50 of adriamycin to MCF-7/S and MCF-7/ADM were 1.773 μg/ml and 43.812μg/ml, respectively. Drug-resistant index of MCF-7/ADM was 24.7. Silymarin increased cell toxic ef-fect of adriamycin. After treated with 10μg/mlsilymarin (inhibition rate was 2.0%) combining with adriamycin for 48h, IC50of adriamycine declined to 7.798μg/ml, and the reversal index was 5.6 (P<0.01). Conclusion Silymarin could partly reverse drug-resistance of MCF- 7/ADMto adriamycinein vitro.%目的 观察水飞蓟素(Silymarin,Sily)对人乳腺癌耐药细胞株MCF-7/ADM的逆转耐药作用.方法 以CCK-8法测定阿霉素(Adm)对人乳腺癌敏感细胞株MCF-7/S和耐药细胞株MCF-7/ADM的毒性作用,计算出耐药倍数.以无细胞毒性的Sily(10μg/mL)作为逆转耐药剂,联合Adm观察其对耐药细胞株MCF-7/ADM的逆转耐药作用,计算得逆转倍数.结果 (1)Adm对MCF-7/S和MCF-7/ADM的半数抑制浓度(IC50)分别为1.773μg/mL和43.812μg/mL,耐药倍数为24.7倍.(2) Sily能够增强ADM对MCF-7/ADM的细胞毒作用.以10μg/mL(抑制率为2.0%)的Sily联合Adm作用于MCF-7/ADM 48h后,耐药细胞株的IC50降至7.798μg/mL,逆转倍数为5.6倍(P<0.01).结论 Sily能够逆转人乳腺癌耐药细胞株MCF-7/ADM的耐药性.

  8. Pokemon对乳腺癌MCF-7细胞侵袭迁移能力的影响%The Effect of Pokemon on the Invasion and Migration Ability of MCF-7 Cells

    Institute of Scientific and Technical Information of China (English)

    祖旭宇; 谭莉; 周茜; 王艺蓁

    2014-01-01

    目的 建立稳定表达pokemon乳腺癌细胞系,并观察pokemon对乳腺癌细胞系MCF-7侵袭转移能力的影响. 方法 构建表达pokemon慢病毒载体,将Pokemon表达慢病毒载体转染MCF-7细胞,通过Westernblot方法检测稳定性表达pokemon MCF-7细胞中Pokemon-GFP融合蛋白的表达情况,应用Transwell试验及划痕实验观察pokemon的高表达对MCF-7细胞侵袭迁移能力的影响. 结果 成功建立稳定表达pokemon的MCF-7细胞系,pokemon可抑制MCF-7细胞侵袭能力. 结论 Pokemon可抑制MCF-7细胞侵袭能力.

  9. Modeling and analysis of passive dynamic bipedal walking with segmented feet and compliant joints

    Science.gov (United States)

    Huang, Yan; Wang, Qi-Ning; Gao, Yue; Xie, Guang-Ming

    2012-10-01

    Passive dynamic walking has been developed as a possible explanation for the efficiency of the human gait. This paper presents a passive dynamic walking model with segmented feet, which makes the bipedal walking gait more close to natural human-like gait. The proposed model extends the simplest walking model with the addition of flat feet and torsional spring based compliance on ankle joints and toe joints, to achieve stable walking on a slope driven by gravity. The push-off phase includes foot rotations around the toe joint and around the toe tip, which shows a great resemblance to human normal walking. This paper investigates the effects of the segmented foot structure on bipedal walking in simulations. The model achieves satisfactory walking results on even or uneven slopes.

  10. Foot Placement Indicator for Balance of Planar Bipeds with Point Feet

    Directory of Open Access Journals (Sweden)

    Pieter van Zutven

    2013-05-01

    Full Text Available Abstract If humanoid robots are to be used in society, they should be able to maintain their balance. Knowing where to step is crucially important. In this paper we contribute an algorithm that can compute the foot step location such that bipedal balance is maintained for planar bipeds with point feet and an arbitrary number of non-massless links on a horizontal and flat ground. The algorithm is called the foot placement indicator (FPI and it extends the foot placement estimator (FPE. The FPE uses an inverted pendulum model to capture the dynamics of a humanoid robot, whereas the FPI deals with multi-body models with distributed masses. This paper analyses equilibrium sets and the stability of planar bipeds with point feet. The algorithm uses conservation of energy throughout the step, taking into account the instantaneous impact dynamics at foot strike. A simulation case study on a five-link planar biped shows the effectiveness of the FPI.

  11. Gait analysis and energy consumption of below-knee amputees wearing three different prosthetic feet.

    Science.gov (United States)

    Huang, G F; Chou, Y L; Su, F C

    2000-10-01

    This study scientifically measures the dynamic gait characteristics and energy consumption of 16 male below-knee amputees, eight vascular and eight traumatic, while wearing solid ankle cushion heel (SACH), single axis and multiple axis prosthetic feet via six-camera motion analysis, metabolic measurement cart and heavy-duty treadmill. Subjective results are additionally determined via questionnaire after testing. Motion analysis showed statistically significant differences at Pmultiple axis foot in the velocity, cadence, stride length and single limb stance. Significant differences were found in energy consumption between the traumatic and vascular groups, and significant changes in walking under different speeds and different inclines. Results provide quantitative and qualitative information about the dynamic performance of the various feet, which can be helpful in prescribing the optimal prosthetic foot for individual amputees.

  12. Modeling and analysis of passive dynamic bipedal walking with segmented feet and compliant joints

    Institute of Scientific and Technical Information of China (English)

    Yan Huang; Qi-Ning Wang; Yue Gao; Guang-Ming Xie

    2012-01-01

    Passive dynamic walking has been developed as a possible explanation for the efficiency of the human gait.This paper presents a passive dynamic walking model with segmented feet,which makes the bipedal walking gait more close to natural human-like gait.The proposed model extends the simplest walking model with the addition of flat feet and torsional spring based compliance on ankle joints and toe joints,to achieve stable walking on a slope driven by gravity.The push-off phase includes foot rotations around the toe joint and around the toe tip,which shows a great resemblance to human normal walking.This paper investigates the effects of the segmented foot structure on bipedal walking in simulations. The model achieves satisfactory walking results on even or uneven slopes.

  13. Biped 4R2C six-bar mechanism with inner and outer feet

    Science.gov (United States)

    Liu, Chao; Wang, Hao; Yao, Yan-an

    2016-01-01

    Most current biped robots are equipped with two feet arranged in the right and left which inspired by the human body system. Different from the existing configurations, a novel biped robot with inner and outer feet based on a spatial six-bar 4R2C(R and C denote revolute and cylindric joints, respectively) mechanism is proposed. It can move along a line or a curve by three walking modes that are dwell adjustment mode, limit position adjustment mode and any position adjustment mode. Kinematic, gait planning and stability analyses are performed respectively, and a prototype is developed. Lastly, a potential application is considered and two manipulating modes(sphere and cylinder manipulating modes) are carried out. This interesting mechanism feathering its single closed-chain structure and unique work performance is expected to motivate the configuration creation of biped robots.

  14. Genu Valgum and Flat Feet in Children With Healthy and Excessive Body Weight.

    Science.gov (United States)

    Jankowicz-Szymanska, Agnieszka; Mikolajczyk, Edyta

    2016-01-01

    To examine the relationship between obesity, genu valgum, and flat feet in children, and find practical implications for therapeutic interventions. A total of 1364 children aged 3-7 years took part in the research. Their body mass index was calculated and their weight status described. Participants' knee alignment was assessed by measuring the intermalleolar distance in the standing position with the knees in contact. The height of the longitudinal arch of each foot was measured using Clarke's angle. The prevalence of overweight and obesity increased with age. Reduction of intermalleolar distance and increased longitudinal arch of the foot, characteristic of typical growth and development, were observed. Genu valgum was more common in children who were overweight. Significant correlations among body mass index, intermalleolar distance, and Clarke's angle (P genu valgum and flat feet.

  15. Foot Placement Indicator for Balance of Planar Bipeds with Point Feet

    Directory of Open Access Journals (Sweden)

    Pieter van Zutven

    2013-05-01

    Full Text Available If humanoid robots are to be used in society, they should be able to maintain their balance. Knowing where to step is crucially important. In this paper we contribute an algorithm that can compute the foot step location such that bipedal balance is maintained for planar bipeds with point feet and an arbitrary number of non‐massless links on a horizontal and flat ground. The algorithm is called the foot placement indicator (FPI and it extends the foot placement estimator (FPE. The FPE uses an inverted pendulum model to capture the dynamics of a humanoid robot, whereas the FPI deals with multi‐body models with distributed masses. This paper analyses equilibrium sets and the stability of planar bipeds with point feet. The algorithm uses conservation of energy throughout the step, taking into account the instantaneous impact dynamics at foot strike. A simulation case study on a five‐link planar biped shows the effectiveness of the FPI.

  16. Stability and control of dynamic walking for a five-link planar biped robot with feet

    Institute of Scientific and Technical Information of China (English)

    Chenglong FU; Ken CHEN; Jing XIONG; Leon XU

    2007-01-01

    During dynamic walking of biped robots, the underactuated rotating degree of freedom (DOF) emerges between the support foot and the ground, which makes the biped model hybrid and dimension-variant. This paper addresses the asymptotic orbit stability for dimension-variant hybrid systems (DVHS). Based on the generalized Poincare map, the stability criterion for DVHS is also presented, and the result is then used to study dynamic walking for a five-link planar biped robot with feet. Time-invariant gait planning and nonlinear control strategy for dynamic walking with flat feet is also introduced. Simulation results indicate that an asymptotically stable limit cycle of dynamic walking is achieved by the proposed method.

  17. Dynamics and Optimal Feet Force Distributions of a Realistic Four-legged Robot

    Directory of Open Access Journals (Sweden)

    Saurav Agarwal

    2012-08-01

    Full Text Available This paper presents a detailed dynamic modeling of realistic four-legged robot. The direct and inverse kinematic analysis for each leg has been considered in order to develop an overall kinematic model of the robot, when it follows a straight path. This study also aims to estimate optimal feet force distributions of the said robot, which is necessary for its real-time control. Three different approaches namely, minimization of norm of feet forces (approach 1, minimization of norm of joint torques (approach 2 and minimization of norm of joint power (approach 3 have been developed. Simulation result shows that approach 3 is more energy efficient foot force formulation than other two approaches. Lagrange-Euler formulation has been utilized to determine the joint torques. The developed dynamic models have been examined through computer simulation of continuous gait of the four-legged robot.

  18. Testing the validity of the Danish urban myth that alcohol can be absorbed through feet: open labelled self experimental study

    DEFF Research Database (Denmark)

    Hansen, Christian Stevns; Færch, Louise; Kristensen, Peter Lommer

    2010-01-01

    To determine the validity of the Danish urban myth that it is possible to get drunk by submerging feet in alcohol.......To determine the validity of the Danish urban myth that it is possible to get drunk by submerging feet in alcohol....

  19. Postural stability effects of random vibration at the feet of construction workers in simulated elevation.

    Science.gov (United States)

    Simeonov, P; Hsiao, H; Powers, J; Ammons, D; Kau, T; Amendola, A

    2011-07-01

    The risk of falls from height on a construction site increases under conditions which degrade workers' postural control. At elevation, workers depend heavily on sensory information from their feet to maintain balance. The study tested two hypotheses: "sensory enhancement"--sub-sensory (undetectable) random mechanical vibrations at the plantar surface of the feet can improve worker's balance at elevation; and "sensory suppression"--supra-sensory (detectable) random mechanical vibrations can have a degrading effect on balance in the same experimental settings. Six young (age 20-35) and six aging (age 45-60) construction workers were tested while standing in standard and semi-tandem postures on instrumented gel insoles. The insoles applied sub- or supra-sensory levels of random mechanical vibrations to the feet. The tests were conducted in a surround-screen virtual reality system, which simulated a narrow plank at elevation on a construction site. Upper body kinematics was assessed with a motion-measurement system. Postural stability effects were evaluated by conventional and statistical mechanics sway measures, as well as trunk angular displacement parameters. Analysis of variance did not confirm the "sensory enhancement" hypothesis, but provided evidence for the "sensory suppression" hypothesis. The supra-sensory vibration had a destabilizing effect, which was considerably stronger in the semi-tandem posture and affected most of the sway variables. Sensory suppression associated with elevated vibration levels on a construction site may increase the danger of losing balance. Construction workers at elevation, e.g., on a beam or narrow plank might be at increased risk of fall if they can detect vibrations under their feet. To reduce the possibility of losing balance, mechanical vibration to supporting structures used as walking/working surfaces should be minimized when performing construction tasks at elevation. Published by Elsevier Ltd.

  20. SOCIAL SPACE, LANGUAGE, AND CONSCIOUSNESS IN HELENA MARÍA VIRAMONTES'S UNDER THE FEET OF JESUS

    Directory of Open Access Journals (Sweden)

    Michael Nieto Garcia

    2004-02-01

    Full Text Available This paper analyzes social space with the tool of postmodern theories of space in the specific case of migrant agricultural workers portrayed in Helena María Viramontes's Under the Feet of Jesus. Language and consciousness are the main vehicles by which Estrella, the central protagonist of the novel, liberates herself from the dominant social discourses-linguistic, racial, economic, and gender-that position her as a neocolonial subject.

  1. Six Feet Under o la muerte nuestra de cada día

    Directory of Open Access Journals (Sweden)

    Francisco Guillermo Medina Montaño

    2015-12-01

    Full Text Available A partir del modelo de análisis ADN de las series televisivas, los autores abordan la serie Six Feet Under, su estructura narrativa, su lenguaje audiovisual, así como la construcción psicológica y moral de los personajes que en ella convergen para así escudriñar los mensajes y valores de una de las obras más vistas en su tipo y en su tiempo.

  2. Variations in daily quality assurance dosimetry from device levelling, feet position and backscatter material.

    Science.gov (United States)

    Ceylan, Abdurrahman; Butson, Martin; Cullen, Ashley; Yu, Peter K N; Alnawaf, Hani

    2012-12-01

    Daily quality assurance procedures are an essential part of radiotherapy medical physics. Devices such as the Sun Nuclear, DQA3 are effective tools for analysis of daily dosimetry including flatness, symmetry, energy, field size and central axis radiation dose measurement. The DQA3 can be used on the treatment couch of the linear accelerator or on a dedicated table/bed for superficial and orthovoltage x-ray machines. This device is levelled using its dedicated feet. This work has shown that depending on the quantity of backscatter material behind the DQA3 device, the position of the levelling feet can affect the measured central axis dose by up to 1.8 % (250 kVp and 6 MV) and that the introduction of more backscatter material behind the DQA3 can lead to up to 7.2 % (6 MV) variations in measured central axis dose. In conditions where no backscatter material is present, dose measurements can vary up to 1 %. As such this work has highlighted the need to keep the material behind the DQA3 device constant as well as maintaining the accuracy of the feet position on the device to effectively measure the most accurate daily constancy achievable. Results have also shown that variations in symmetry and energy calculations of up to 1 % can occur if the device is not levelled appropriately. As such, we recommend the position of the levelling feet on the device be as close as possible to the device so that a constant distance is kept between the DQA3 and the treatment couch and thus minimal levelling variations also occur. We would also recommend having no extra backscattering material behind the DQA3 device during use to minimise any variations which might occur from these backscattering effects.

  3. Spinal cord lesions shrink peripersonal space around the feet, passive mobilization of paraplegic limbs restores it.

    Science.gov (United States)

    Scandola, Michele; Aglioti, Salvatore Maria; Bonente, Claudio; Avesani, Renato; Moro, Valentina

    2016-04-06

    Peripersonal space (PPS) is the space surrounding us within which we interact with objects. PPS may be modulated by actions (e.g. when using tools) or sense of ownership (e.g. over a rubber hand). Indeed, intense and/or prolonged use of a tool may induce a sense of ownership over it. Conversely, inducing ownership over a rubber hand may activate brain regions involved in motor control. However, the extent to which PPS is modulated by action-dependent or ownership-dependent mechanisms remains unclear. Here, we explored the PPS around the feet and the sense of ownership over lower limbs in people with Paraplegia following Complete spinal cord Lesions (PCL) and in healthy subjects. PCL people can move their upper body but have lost all sensory-motor functions in their lower body (e.g. lower limbs). We tested whether PPS alterations reflect the topographical representations of various body parts. We found that the PPS around the feet was impaired in PCL who however had a normal representation of the PPS around the hands. Significantly, passive mobilization of paraplegic limbs restored the PPS around the feet suggesting that activating action representations in PCL brings about short-term changes of PPS that may thus be more plastic than previously believed.

  4. Function of the triceps surae muscle group in low and high arched feet: an exploratory study.

    Science.gov (United States)

    Branthwaite, Helen; Pandyan, Anand; Chockalingam, Nachiappan

    2012-06-01

    The Achilles tendon has been shown to be comprised of segmental components of tendon arising from the tricpes surae muscle group. Motion of the foot joints in low and high arched feet may induce a change in behaviour of the triceps surae muscle group due to altered strain on the tendon. Surface electromyogram of the medial and lateral gastrocnemius and the soleus muscle from 12 subjects (with 6 low arched and 6 high arched feet) (1:1) was recorded whilst walking at a self selected speed along a 10m walkway. The results showed a high variability in muscle activity between groups with patterns emerging within groups. Soleus was more active in 50% of the low arch feet at forefoot loading and there was a crescendo of activity towards heel lift in 58% of all subjects. This observed variability between groups and foot types emphasises the need for further work on individual anatomical variation and foot function to help in the understanding and management of Achilles tendon pathologies and triceps surae dysfunction.

  5. Enhanced stress response by a bilateral feet compared to a unilateral hand Cold Pressor Test.

    Science.gov (United States)

    Larra, Mauro F; Schilling, Thomas M; Röhrig, Philipp; Schächinger, Hartmut

    2015-01-01

    The Cold Pressor Test (CPT) is a frequently employed laboratory stress protocol. However, with many experimental designs the application in its classic form (immersion of the dominant hand into ice-water) is problematic as unilateral stimulation may need to be avoided and/or hands are required for further measurements. Here, we describe a simple modification of the classic CPT in which both feet are immersed into ice-water and compare the evoked neuroendocrine stress response to the classic CPT in a within-subjects design. Twenty-four healthy participants were exposed to each of both CPT versions on two subsequent days in randomized order. Heart rate, blood pressure, salivary alpha-amylase and cortisol were measured at baseline and during or after CPT exposition, respectively, along with subjective ratings of pain and stress. The bilateral feet CPT induced marked increases in all measured stress parameters. Moreover, with the exception of blood pressure, autonomic and endocrine responses were enhanced compared to the classic CPT. The bilateral feet CPT thus is a valid and simple modification and may be useful when the application of the classic CPT is unfeasible or a stronger neuroendocrine stress response is of interest.

  6. Effect of medial arterial calcification on O2 supply to exercising diabetic feet.

    Science.gov (United States)

    Chantelau, E; Ma, X Y; Herrnberger, S; Dohmen, C; Trappe, P; Baba, T

    1990-08-01

    We investigated whether medial arterial calcification (MAC) impairs O2 supply to the exercising foot in diabetic patients with foot lesions. Transcutaneous O2 tension (tcPO2) was monitored at the dorsum of the foot before and after bicycle exercise in 11 diabetic patients with peripheral ischemic vascular disease (PIVD) with or without concomitant existence of MAC, 10 patients with MAC but without PIVD, 10 diabetic control subjects, and 6 nondiabetic control subjects. The mean preexercise tcPO2 level was comparable in these four groups. However, tcPO2 decreased significantly with exercise in feet with PIVD (mean +/- SE -17.9 +/- 2.7%, P less than 0.01, n = 11), regardless of presence or absence of vascular calcification. On the other hand, the value increased significantly with exercise in feet with MAC but without PIVD (21.2 +/- 3.5%, P less than 0.01, n = 10) and in those of diabetic control subjects (14.9 +/- 3.6%, P less than 0.01), respectively. The tcPO2 remained unchanged in the feet of nondiabetic control subjects (1.7 +/- 1.1%). The results suggest that MAC is not associated with reduced O2 supply to the exercising foot in diabetic patients.

  7. Doppler sonography of diabetic feet: Quantitative analysis of blood flow volume

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Young Lan; Kim, Ho Chul; Choi, Chul Soon; Yoon, Dae Young; Han, Dae Hee; Moon, Jeung Hee; Bae, Sang Hoon [Hallym University College of Medicine, Seoul (Korea, Republic of)

    2002-09-15

    To analyze Doppler sonographic findings of diabetic feet by estimating the quantitative blood flow volume and by analyzing waveform on Doppler. Doppler sonography was performed in thirty four patients (10 diabetic patients with foot ulceration, 14 diabetic patients without ulceration and 10 normal patients as the normal control group) to measure the flow volume of the arteries of the lower extremities (posterior and anterior tibial arteries, and distal femoral artery. Analysis of doppler waveforms was also done to evaluate the nature of the changed blood flow volume of diabetic patients, and the waveforms were classified into triphasic, biphasic-1, biphasic-2 and monophasic patterns. Flow volume of arteries in diabetic patients with foot ulceration was increased witha statistical significance when compared to that of diabetes patients without foot ulceration of that of normal control group (P<0.05). Analysis of Doppler waveform revealed that the frequency of biphasic-2 pattern was significantly higher in diabetic patients than in normal control group(p<0.05). Doppler sonography in diabetic feet showed increased flow volume and biphasic Doppler waveform, and these findings suggest neuropathy rather than ischemic changes in diabetic feet.

  8. Evidence for rotational motions in the feet of a quiescent solar prominence

    CERN Document Server

    Suárez, D Orozco; Bueno, J Trujillo

    2012-01-01

    We present observational evidence of apparent plasma rotational motions in the feet of a solar prominence. Our study is based on spectroscopic observations taken in the He I 1083.0 nm multiplet with the Tenerife Infrared Polarimeter attached to the German Vacuum Tower Telescope. We recorded a time sequence of spectra with 34 s cadence placing the slit of the spectrograph almost parallel to the solar limb and crossing two feet of an intermediate size, quiescent hedgerow prominence. The data show opposite Doppler shifts, +/- 6 km/s, at the edges of the prominence feet. We argue that these shifts may be interpreted as prominence plasma rotating counterclockwise around the vertical axis to the solar surface as viewed from above. The evolution of the prominence seen in EUV images taken with the Solar Dynamic Observatory provided us clues to interpret the results as swirling motions. Moreover, time-distance images taken far from the central wavelength show plasma structures moving parallel to the solar limb with ve...

  9. CT-guided percutaneous laser photocoagulation of osteoid osteomas of the hands and feet

    Energy Technology Data Exchange (ETDEWEB)

    Zouari, Leila; Bousson, Valerie; Hamze, Bassam; Roqueplan, Francois; Laredo, Jean-Denis [Hopital Lariboisiere, Service de Radiologie Osteo-Articulaire, Paris (France); Roulot, Eric [Clinique Jouvenet, Institut de la main, Paris (France)

    2008-11-15

    Percutaneous local ablation of osteoid osteoma has largely replaced surgery, except in the small bones of the hands and feet. The objective of this study was to describe the technical specificities and results of computed tomography (CT)-guided percutaneous laser photocoagulation in 15 patients with osteoid osteomas of the hands and feet. We retrospectively examined the medical charts of the 15 patients who were treated with CT-guided percutaneous laser photocoagulation therapy at our institution between 1994 and 2004. The 15 patients had a mean age of 24.33 years. None of them had received any prior surgical or percutaneous treatment for the osteoid osteoma. The follow-up period was 24 to 96 months (mean, 49.93). The pain resolved completely within 1 week. Fourteen patients remained symptom-free throughout the follow-up period; the remaining patient experienced a recurrence of pain after 24 months, underwent a second laser photocoagulation procedure, and was symptom-free at last follow-up 45 months later. No adverse events related to the procedure or to the location of the tumor in the hand or the foot were recorded. CT-guided percutaneous laser photocoagulation is an alternative to surgery for the treatment of osteoid osteomas of the hands and feet. (orig.)

  10. Segmental kinematic analysis of planovalgus feet during walking in children with cerebral palsy.

    Science.gov (United States)

    Kruger, Karen M; Konop, Katherine A; Krzak, Joseph J; Graf, Adam; Altiok, Haluk; Smith, Peter A; Harris, Gerald F

    2017-05-01

    Pes planovalgus (flatfoot) is a common deformity among children with cerebral palsy. The Milwaukee Foot Model (MFM), a multi-segmental kinematic foot model, which uses radiography to align the underlying bony anatomy with reflective surface markers, was used to evaluate 20 pediatric participants (30feet) with planovalgus secondary to cerebral palsy prior to surgery. Three-dimensional kinematics of the tibia, hindfoot, forefoot, and hallux segments are reported and compared to an age-matched control set of typically-developing children. Most results were consistent with known characteristics of the deformity and showed decreased plantar flexion of the forefoot relative to hindfoot, increased forefoot abduction, and decreased ranges of motion during push-off in the planovalgus group. Interestingly, while forefoot characteristics were uniformly distributed in a common direction in the transverse plane, there was marked variability of forefoot and hindfoot coronal plane and hindfoot transverse plane positioning. The key finding of these data was the radiographic indexing of the MFM was able to show flat feet in cerebral palsy do not always demonstrate more hindfoot eversion than the typically-developing hindfoot. The coronal plane kinematics of the hindfoot show cases planovalgus feet with the hindfoot in inversion, eversion, and neutral. Along with other metrics, the MFM can be a valuable tool for monitoring kinematic deformity, facilitating clinical decision making, and providing a quantitative analysis of surgical effects on the planovalgus foot. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Foot reflexology in feet impairment of people with type 2 diabetes mellitus: randomized trial

    Directory of Open Access Journals (Sweden)

    Natália Chantal Magalhães da Silva

    2015-08-01

    Full Text Available AbstractObjective: to evaluate the effect of foot reflexology on feet impairment of people with type 2 diabetes mellitus.Method: this is a randomized, controlled and blind clinical trial. The sample was comprised by people with type 2 diabetes mellitus who, after being randomized into Treated group (n = 21 and Control group (n = 24, received guidelines on foot self-care. To the Treated Group it was also provided 12 sessions of foot reflexology. The scores of impairment indicators related to skin and hair, blood circulation, tissue sensitivity and temperature were measured by means of the instrument for assessing tissue integrity of the feet of people with diabetes mellitus. Chi-square test, Fisher exact test, Mann-Whitney test and regression analyzes were applied to the data, considering a significance level of 5% (P value <0.05.Results: participants who received the therapy showed better scores in some impairment indicators related to skin and hair (hair growth, elasticity/turgor, hydration, perspiration, texture and integrity of the skin/ skin peeling.Conclusion: the foot reflexology had a beneficial effect on feet impairment of people with type 2 diabetes mellitus, which makes it a viable therapy, deserving investment. This study was registered in the Brazilian Registry of Clinical Trials - RBR-8zk8sz.

  12. Normative data for cutaneous threshold and spatial discrimination in the feet.

    Science.gov (United States)

    Rinkel, Willem D; Aziz, M Hosein; Van Deelen, Meike J M; Willemsen, Sten P; Castro Cabezas, Manuel; Van Neck, Johan W; Coert, J Henk

    2017-09-01

    No data are available for normative values of cutaneous threshold and spatial discrimination in the feet. We developed clinically applicable reference values in relation to the nerve distributions of the feet. We determined foot sensation in 196 healthy individuals. Cutaneous threshold (1-point static discrimination, S1PD) was tested with monofilaments (0.008 to 300 gram) and spatial discrimination (2-point static [S2PD] and moving [M2PD] discrimination) on five locations per foot. There was a significant age-dependent increase in S1PD, S2PD, and M2PD values (P < 0.05). No significant differences were found between both feet. S1PD values differed up to 0.8 g between genders. There were no significant differences between genders for S2PD and M2PD measurements. M2PD values were generally lower than S2PD values. This study provides age-related normative values for foot sensation to help clinicians assess sensory deficits in relation to aging and identify patients with underlying nerve problems. Muscle Nerve 56: 399-407, 2017. © 2016 Wiley Periodicals, Inc.

  13. Pokemon对乳腺癌MCF-7细胞侵袭迁移能力的影响

    Institute of Scientific and Technical Information of China (English)

    祖旭宇; 谭莉; 周茜; 王艺蓁

    2014-01-01

    目的 建立稳定表达pokemon乳腺癌细胞系,并观察pokemon对乳腺癌细胞系MCF-7侵袭转移能力的影响. 方法 构建表达pokemon慢病毒载体,将Pokemon表达慢病毒载体转染MCF-7细胞,通过Westernblot方法检测稳定性表达pokemon MCF-7细胞中Pokemon-GFP融合蛋白的表达情况,应用Transwell试验及划痕实验观察pokemon的高表达对MCF-7细胞侵袭迁移能力的影响. 结果 成功建立稳定表达pokemon的MCF-7细胞系,pokemon可抑制MCF-7细胞侵袭能力. 结论 Pokemon可抑制MCF-7细胞侵袭能力.

  14. In situ synthesized BSA capped gold nanoparticles: Effective carrier of anticancer drug Methotrexate to MCF-7 breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Murawala, Priyanka [Physical and Materials Chemistry Division, National Chemical Laboratory, Pune 411008 (India); Tirmale, Amruta [Physical and Materials Chemistry Division, National Chemical Laboratory, Pune 411008 (India); National Centre for Cell Science, NCCS, Pune 411007 (India); Shiras, Anjali, E-mail: anjalishiras@nccs.res.in [National Centre for Cell Science, NCCS, Pune 411007 (India); Prasad, B.L.V., E-mail: pl.bhagavatula@ncl.res.in [Physical and Materials Chemistry Division, National Chemical Laboratory, Pune 411008 (India)

    2014-01-01

    The proficiency of MTX loaded BSA capped gold nanoparticles (Au-BSA-MTX) in inhibiting the proliferation of breast cancer cells MCF-7 as compared to the free drug Methotrexate (MTX) is demonstrated based on MTT and Ki-67 proliferation assays. In addition, DNA ladder gel electrophoresis studies, flow cytometry and TUNEL assay confirmed the induction of apoptosis by MTX and Au-BSA-MTX in MCF-7 cells. Notably, Au-BSA-MTX was found to have higher cytotoxicity on MCF-7 cells compared with an equivalent dose of free MTX. The enhanced activity is attributed to the preferential uptake of Au-BSA-MTX particles by MCF-7 cells due to the presence of BSA that acts as a source of nutrient and energy to the rapidly proliferating MCF-7 cells. Moreover, the targeting ability of the drug MTX to the over expressed folate receptors on MCF-7 cells also contributes to the enhanced uptake and activity. Taken together, these results unveil that Au-BSA-MTX could be more effective than free drug for cancer treatment. - Highlights: • Gold nanoparticles prepared using bovine serum albumin as a reducing and capping agent. • These gold nanoparticles are extremely stable under strong electrolyte and pH conditions. • The anticancer drug methotrexate has been loaded on the Au-BSA nanoparticles. • Due to BSA loading these are taken up by cancerous cells preferentially. • Better proficiency in inhibiting MCF-7 cells as compared to the free drug Methotrexate is demonstrated.

  15. Peroxiredoxin I and II inhibit H2O2-induced cell death in MCF-7 cell lines.

    Science.gov (United States)

    Bae, Ji-Yeon; Ahn, Soo-Jung; Han, Wonshik; Noh, Dong-Young

    2007-07-01

    Apoptosis is known to be induced by direct oxidative damage due to oxygen-free radicals or hydrogen peroxide or by their generation in cells by the actions of injurious agents. Together with glutathione peroxidase and catalase, peroxiredoxin (Prx) enzymes play an important role in eliminating peroxides generated during metabolism. We investigated the role of Prx enzymes during cellular response to oxidative stress. Using Prx isoforms-specific antibodies, we investigated the presence of Prx isoforms by immunoblot analysis in cell lysates of the MCF-7 breast cancer cell line. Treatment of MCF-7 with hydrogen peroxide (H2O2) resulted in the dose-dependent expressions of Prx I and II at the protein and mRNA levels. To investigate the physiologic relevance of the Prx I and II expressions induced by H2O2, we compared the survivals of MCF10A normal breast cell line and MCF-7 breast cancer cell line following exposure to H2O2. The treatment of MCF10A with H2O2 resulted in rapid cell death, whereas MCF-7 was resistant to H2O2. In addition, we found that Prx I and II transfection enabled MCF10A cells to resist H2O2-induced cell death. These findings suggest that Prx I and II have important functions as inhibitors of cell death during cellular response to oxidative stress.

  16. Photoactivated hypericin increases the expression of SOD-2 and makes MCF-7 cells resistant to photodynamic therapy.

    Science.gov (United States)

    Kimáková, Patrícia; Solár, Peter; Fecková, Barbora; Sačková, Veronika; Solárová, Zuzana; Ilkovičová, Lenka; Kello, Martin

    2017-01-01

    Photoactivated hypericin increased production of reactive oxygen species in human breast adenocarcinoma MCF-7 as well as in MDA-MB-231 cells 1h after photodynamic therapy. On the other hand, reactive oxygen species dropped 3h after photodynamic therapy with hypericin, but only in MCF-7 cells, whereas in MDA-MB-231 cells remained elevated. The difference in the dynamics of reactive oxygen species after hypericin activation was related to increased activity of SOD-2 in MCF-7 cells compared to MDA-MB-231 cells. Indeed, photodynamic therapy with hypericin significantly increased SOD-2 activity in MCF-7 cells, but only slightly in MDA-MB-231 cells. In this regard, SOD-2 activity correlated well with enhanced both mRNA expression as well as SOD-2 protein level in MCF-7 cells. The role of SOD-2 in the resistance of MCF-7 cells to photodynamic therapy with hypericin was monitored using SOD-2 inhibitor - 2-methoxyestradiol. Interestingly, the combination of photodynamic therapy with hypericin and methoxyestradiol sensitized MCF-7 cells to photodynamic therapy and significantly reduced its clonogenic ability. Furthermore, methoxyestradiol potentiated the activation of caspase 3/7 and apoptosis induced by photodynamic therapy with hypericin. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  17. Synthesis, structural characterization, and anticancer activity of a monobenzyltin compound against MCF-7 breast cancer cells

    Directory of Open Access Journals (Sweden)

    Fani S

    2015-11-01

    Full Text Available Somayeh Fani,1 Behnam Kamalidehghan,1 Kong Mun Lo,2 Najihah Mohd Hashim,1 Kit May Chow,2 Fatemeh Ahmadipour1 1Department of Pharmacy, Faculty of Medicine, 2Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia Abstract: A new monoorganotin Schiff base compound, [N-(3,5-dichloro-2-oxidobenzylidene-4-chlorobenzyhydrazidato](o-methylbenzylaquatin(IV chloride, (compound C1, was synthesized, and its structural features were investigated by spectroscopic techniques and single-crystal X-ray diffractometry. Compound C1 was exposed to several human cancer cell lines, including breast adenocarcinoma cell lines MCF-7 and MDA-MB-231, ovarian adenocarcinoma cell lines Skov3 and Caov3, and prostate cancer cell line PC3, in order to examine its cytotoxic effect for different forms of cancer. Human hepatic cell line WRL-68 was used as a normal cell line. We concentrated on the MCF-7 cell line to detect possible underlying mechanism involvement of compound C1. 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT assay revealed the strongest cytotoxicity of compound C1 against MCF-7 cells, with a half maximal inhibitory concentration (IC50 value of 2.5±0.50 µg/mL after 48 hours treatment. The IC50 value was >30 µg/mL in WRL-68 cells. Induced antiproliferative activity of compound C1 for MCF-7 cells was further confirmed by lactate dehydrogenase, reactive oxygen species, acridine orange/propidium iodide staining, and DNA fragmentation assays. A significant increase of lactate dehydrogenase release in treated cells was observed via fluorescence analysis. Luminescent analysis showed significant growth in intracellular reactive oxygen species production after treatment. Morphological changes of necrosis and early and late apoptosis stages were observed in treated cells after staining with acridine orange/propidium iodide. DNA fragmentation was observed as a characteristic of apoptosis in treated cells. Results of the

  18. Cubic ideal ferromagnets at low temperature and weak magnetic field

    Science.gov (United States)

    Hofmann, Christoph P.

    2017-04-01

    The low-temperature series for the free energy density, pressure, magnetization and susceptibility of cubic ideal ferromagnets in weak external magnetic fields are discussed within the effective Lagrangian framework up to three loops. The structure of the simple, body-centered, and face-centered cubic lattice is taken into account explicitly. The expansion involves integer and half-integer powers of the temperature. The corresponding coefficients depend on the magnetic field and on low-energy effective constants that can be expressed in terms of microscopic quantities. Our formulas may also serve as efficiency or consistency check for other techniques like Green's function methods, where spurious terms in the low-temperature expansion have appeared. We explore the sign and magnitude of the spin-wave interaction in the pressure, magnetization and susceptibility, and emphasize that our effective field theory approach is fully systematic and rigorous.

  19. Counting real cubics with passage/tangency conditions

    CERN Document Server

    Lanzat, Sergei

    2010-01-01

    We study the following question: given a set of seven points and an immersed curve in the real plane R^2, all in general position, how many real rational nodal plane cubics pass through these points and are tangent to this curve. We count each such cubic with a certain sign, and present an explicit formula for their algebraic number. This number is preserved under small regular homotopies of the curve, but jumps (in a well-controlled way) when in the process of homotopy we pass a certain singular discriminant. We discuss the relation of such enumerative problems with finite type invariants. Our approach is based on maps of configuration spaces and the intersection theory in the spirit of classical algebraic topology.

  20. Reversible Nanoparticle Cubic Lattices in Blue Phase Liquid Crystals.

    Science.gov (United States)

    Gharbi, Mohamed Amine; Manet, Sabine; Lhermitte, Julien; Brown, Sarah; Milette, Jonathan; Toader, Violeta; Sutton, Mark; Reven, Linda

    2016-03-22

    Blue phases (BPs), a distinct class of liquid crystals (LCs) with 3D periodic ordering of double twist cylinders involving orthogonal helical director twists, have been theoretically studied as potential templates for tunable colloidal crystals. Here, we report the spontaneous formation of thermally reversible, cubic crystal nanoparticle (NP) assemblies in BPs. Gold NPs, functionalized to be highly miscible in cyanobiphenyl-based LCs, were dispersed in BP mixtures and characterized by polarized optical microscopy and synchrotron small-angle X-ray scattering (SAXS). The NPs assemble by selectively migrating to periodic strong trapping sites in the BP disclination lines. The NP lattice, remarkably robust given the small particle size (4.5 nm diameter), is commensurate with that of the BP matrix. At the BP I to BP II phase transition, the NP lattice reversibly switches between two different cubic structures. The simultaneous presence of two different symmetries in a single material presents an interesting opportunity to develop novel dynamic optical materials.

  1. Highly Aminated Mesoporous Silica Nanoparticles with Cubic Pore Structure

    KAUST Repository

    Suteewong, Teeraporn

    2011-01-19

    Mesoporous silica with cubic symmetry has attracted interest from researchers for some time. Here, we present the room temperature synthesis of mesoporous silica nanoparticles possessing cubic Pm3n symmetry with very high molar ratios (>50%) of 3-aminopropyl triethoxysilane. The synthesis is robust allowing, for example, co-condensation of organic dyes without loss of structure. By means of pore expander molecules, the pore size can be enlarged from 2.7 to 5 nm, while particle size decreases. Adding pore expander and co-condensing fluorescent dyes in the same synthesis reduces average particle size further down to 100 nm. After PEGylation, such fluorescent aminated mesoporous silica nanoparticles are spontaneously taken up by cells as demonstrated by fluorescence microscopy.

  2. The Piecewise Cubic Method (PCM) for computational fluid dynamics

    Science.gov (United States)

    Lee, Dongwook; Faller, Hugues; Reyes, Adam

    2017-07-01

    We present a new high-order finite volume reconstruction method for hyperbolic conservation laws. The method is based on a piecewise cubic polynomial which provides its solutions a fifth-order accuracy in space. The spatially reconstructed solutions are evolved in time with a fourth-order accuracy by tracing the characteristics of the cubic polynomials. As a result, our temporal update scheme provides a significantly simpler and computationally more efficient approach in achieving fourth order accuracy in time, relative to the comparable fourth-order Runge-Kutta method. We demonstrate that the solutions of PCM converges at fifth-order in solving 1D smooth flows described by hyperbolic conservation laws. We test the new scheme on a range of numerical experiments, including both gas dynamics and magnetohydrodynamics applications in multiple spatial dimensions.

  3. The Piecewise Cubic Method (PCM) for Computational Fluid Dynamics

    CERN Document Server

    Lee, Dongwook; Reyes, Adam

    2016-01-01

    We present a new high-order finite volume reconstruction method for hyperbolic conservation laws. The method is based on a piecewise cubic polynomial which provides its solutions a fifth-order accuracy in space. The spatially reconstructed solutions are evolved in time with a fourth-order accuracy by tracing the characteristics of the cubic polynomials. As a result, our temporal update scheme provides a significantly simpler and computationally more efficient approach in achieving fourth order accuracy in time, relative to the comparable fourth-order Runge-Kutta method. We demonstrate that the solutions of PCM converges in fifth-order in solving 1D smooth flows described by hyperbolic conservation laws. We test the new scheme in a range of numerical experiments, including both gas dynamics and magnetohydrodynamics applications in multiple spatial dimensions.

  4. Cubic Composite Sensor with Photodiodes for Tracking Solar Orientation

    Directory of Open Access Journals (Sweden)

    Yong-Nong Chang

    2013-01-01

    Full Text Available A cubic composite solar sensor with photo diode is proposed for tracking the relative solar orientation. The proposed solar sensor composes of five photodiode detectors which are placed on the front, rear, left, right, and horizontal facets in a cubic body, respectively. The solar detectors placed on five facets can detect solar power of different facets. Based on the geometric coordinate transformation principle, the relationship equations of solar light orientation between measured powers with respect to various facets can be conducted. As a result, the solar orientation can be precisely achieved without needing any assistance of electronic compass and extra orientation angle corrector. Eventually, the relative solar light orientation, the elevation angle, and azimuth angle of the solar light can be measured precisely.

  5. Nonlinear optical imaging of defects in cubic silicon carbide epilayers.

    Science.gov (United States)

    Hristu, Radu; Stanciu, Stefan G; Tranca, Denis E; Matei, Alecs; Stanciu, George A

    2014-06-11

    Silicon carbide is one of the most promising materials for power electronic devices capable of operating at extreme conditions. The widespread application of silicon carbide power devices is however limited by the presence of structural defects in silicon carbide epilayers. Our experiment demonstrates that optical second harmonic generation imaging represents a viable solution for characterizing structural defects such as stacking faults, dislocations and double positioning boundaries in cubic silicon carbide layers. X-ray diffraction and optical second harmonic rotational anisotropy were used to confirm the growth of the cubic polytype, atomic force microscopy was used to support the identification of silicon carbide defects based on their distinct shape, while second harmonic generation microscopy revealed the detailed structure of the defects. Our results show that this fast and noninvasive investigation method can identify defects which appear during the crystal growth and can be used to certify areas within the silicon carbide epilayer that have optimal quality.

  6. Global Sufficient Optimality Conditions for a Special Cubic Minimization Problem

    Directory of Open Access Journals (Sweden)

    Xiaomei Zhang

    2012-01-01

    Full Text Available We present some sufficient global optimality conditions for a special cubic minimization problem with box constraints or binary constraints by extending the global subdifferential approach proposed by V. Jeyakumar et al. (2006. The present conditions generalize the results developed in the work of V. Jeyakumar et al. where a quadratic minimization problem with box constraints or binary constraints was considered. In addition, a special diagonal matrix is constructed, which is used to provide a convenient method for justifying the proposed sufficient conditions. Then, the reformulation of the sufficient conditions follows. It is worth noting that this reformulation is also applicable to the quadratic minimization problem with box or binary constraints considered in the works of V. Jeyakumar et al. (2006 and Y. Wang et al. (2010. Finally some examples demonstrate that our optimality conditions can effectively be used for identifying global minimizers of the certain nonconvex cubic minimization problem.

  7. Plasma simulation with the Differential Algebraic Cubic Interpolated Propagation scheme

    Energy Technology Data Exchange (ETDEWEB)

    Utsumi, Takayuki [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-03-01

    A computer code based on the Differential Algebraic Cubic Interpolated Propagation scheme has been developed for the numerical solution of the Boltzmann equation for a one-dimensional plasma with immobile ions. The scheme advects the distribution function and its first derivatives in the phase space for one time step by using a numerical integration method for ordinary differential equations, and reconstructs the profile in phase space by using a cubic polynomial within a grid cell. The method gives stable and accurate results, and is efficient. It is successfully applied to a number of equations; the Vlasov equation, the Boltzmann equation with the Fokker-Planck or the Bhatnagar-Gross-Krook (BGK) collision term and the relativistic Vlasov equation. The method can be generalized in a straightforward way to treat cases such as problems with nonperiodic boundary conditions and higher dimensional problems. (author)

  8. Quantum spectra and classical periodic orbit in the cubic billiard

    Institute of Scientific and Technical Information of China (English)

    Dehua Wang; Yongjiang Yu; Shenglu Lin

    2006-01-01

    Quantum billiards have attracted much interest in many fields. People have made a lot of researches on the two-dimensional (2D) billiard systems. Contrary to the 2D billiard, due to the complication of its classical periodic orbits, no one has studied the correspondence between the quantum spectra and the classical orbits of the three-dimensional (3D) billiards. Taking the cubic billiard as an example, using the periodic orbit theory, we find the periodic orbit of the cubic billiard and study the correspondence between the quantum spectra and the length of the classical orbits in 3D system. The Fourier transformed spectrum of this system has allowed direct comparison between peaks in such plot and the length of the periodic orbits, which verifies the correctness of the periodic orbit theory. This is another example showing that semiclassical method provides a bridge between quantum and classical mechanics.

  9. Quantum Phase Transitions in Anti-ferromagnetic Planar Cubic Lattices

    CERN Document Server

    Wellard, C J; Wellard, Cameron; Orus, Roman

    2004-01-01

    Motivated by its relation to an NP-hard problem we analyze the ground state properties of anti-ferromagnetic Ising-spin networks in planar cubic lattices under the action of homogeneous transverse and longitudinal magnetic fields. We consider different instances of the cubic geometry and find a set of quantum phase transitions for each one of the systems, which we characterize by means of entanglement behavior and majorization theory. Entanglement scaling at the critical region is in agreement with results arising from conformal symmetry, therefore even the simplest planar systems can display very large amounts of quantum correlation. No conclusion can be made as to the scaling behavior of the minimum energy gap, with the data allowing equally good fits to exponential and power law decays. Analysis of entanglement and especially of majorization instead of the energy spectrum proves to be a good way of detecting quantum phase transitions in highly frustrated configurations.

  10. Higher-Order Approximation of Cubic-Quintic Duffing Model

    DEFF Research Database (Denmark)

    Ganji, S. S.; Barari, Amin; Babazadeh, H.

    2011-01-01

    We apply an Artificial Parameter Lindstedt-Poincaré Method (APL-PM) to find improved approximate solutions for strongly nonlinear Duffing oscillations with cubic-quintic nonlinear restoring force. This approach yields simple linear algebraic equations instead of nonlinear algebraic equations...... without analytical solution which makes it a unique solution. It is demonstrated that this method works very well for the whole range of parameters in the case of the cubic-quintic oscillator, and excellent agreement of the approximate frequencies with the exact one has been observed and discussed....... Moreover, it is not limited to the small parameter such as in the classical perturbation method. Interestingly, this study revealed that the relative error percentage in the second-order approximate analytical period is less than 0.042% for the whole parameter values. In addition, we compared...

  11. 3D Medical Image Interpolation Based on Parametric Cubic Convolution

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In the process of display, manipulation and analysis of biomedical image data, they usually need to be converted to data of isotropic discretization through the process of interpolation, while the cubic convolution interpolation is widely used due to its good tradeoff between computational cost and accuracy. In this paper, we present a whole concept for the 3D medical image interpolation based on cubic convolution, and the six methods, with the different sharp control parameter, which are formulated in details. Furthermore, we also give an objective comparison for these methods using data sets with the different slice spacing. Each slice in these data sets is estimated by each interpolation method and compared with the original slice using three measures: mean-squared difference, number of sites of disagreement, and largest difference. According to the experimental results, we present a recommendation for 3D medical images under the different situations in the end.

  12. Experimental core electron density of cubic boron nitride

    DEFF Research Database (Denmark)

    Wahlberg, Nanna; Bindzus, Niels; Bjerg, Lasse

    candidate because of its many similarities with diamond: bonding pattern in the extended network structure, hardness, and the quality of the crystallites.3 However, some degree ionic interaction is a part of the bonding in boron nitride, which is not present in diamond. By investigating the core density...... beyond multipolar modeling of the valence density. As was recently shown in a benchmark study of diamond by Bindzus et al.1 The next step is to investigate more complicated chemical bonding motives, to determine the effect of bonding on the core density. Cubic boron nitride2 lends itself as a perfect...... in boron nitride we may obtain a deeper understanding of the effect of bonding on the total density. We report here a thorough investigation of the charge density of cubic boron nitride with a detailed modelling of the inner atom charge density. By combining high resolution powder X-ray diffraction data...

  13. Relaxin Stimulates cAMP Production in MCF-7 Cells upon Overexpression of Type V Adenylyl Cyclase

    OpenAIRE

    Nguyen, Bao T.; Dessauer, Carmen W.

    2005-01-01

    Relaxin stimulates cAMP production and activation of ERK and PI3K in THP-1 cells. Relaxin also stimulates protein kinase C zeta (PKCζ) translocation to the plasma membrane in a PI3K-dependent manner in THP-1 and MCF-7 cells. However, relaxin did not increase cAMP production in MCF-7 cells. We overexpressed different adenylyl cyclase (AC) isoforms in MCF-7 cells to examine coupling of endogenous relaxin receptors to cAMP production. Overexpression of types II and IV AC had no effect on cAMP pr...

  14. Preliminary Investigation of Myo-Inositol Phosphates Produced by ASUIA279 Phytase on MCF-7 Cancer Cells

    Directory of Open Access Journals (Sweden)

    N. Mohd. Yusoff

    2011-12-01

    Full Text Available Phytate or myo-inositol hexakisphosphates (IP6 is widely distributed in plants like rice brans. The production of myo-inositol phosphate intermediates has received much attention due to the remarkable potential health benefits offered by the compounds. In this study, the cytotoxicity of the partially purified myo-inositol phosphate fractions and commercial IP1 and IP6 were investigated against MCF-7 breast cancer cell lines. The study showed that the commercial standard IP1 and IP6 showed good inhibition towards the MCF-7 cell line. The MCF-7 cells growth was inhibited in minimum concentration of myo-inositol phosphates (<1000 µg/ml. However, no inhibition observed on the MCF-7 cell line by the myo-inositol phosphates fractions partially purified from rice bran at concentration <1000 ?g/ml. The inhibition of MCF-7 was only observed at concentration more than 30 mg/ml with more than 40% cells were inhibited. This indicates that the partially purified rice bran myo-inositol phosphates degraded by ASUIA279 phytase on MCF-7 breast cancer cells exhibit positive results towards the inhibition of cancer cells growth at relatively high concentration..KEYWORDS: myo-inositol phosphates, phytase, MCF-7,  cancerABSTRAK: Fitat atau myo-inositol hexakisphosphate (IP6 dikenali umum teragih di dalam tumbuhan seperti dedak padi. Penghasilan perantaraan fosfat myo-inositol mendapat perhatian memandangkan ia berpotensi tinggi dalam kesihatan. Dalam kajian ini, kesitotoksikan sebahagian daripada fosfat myo-inositol separa tulen, IP1 komersil dan IP6 komersil dikaji terhadap produk yang berupa sel kekal (cell lines kanser payu dara MCF-7. Tumbesaran sel MCF-7 direncatkan dalam pekatan minima fosfat myo-inositol (<1000 μg/ml. Tetapi, tidak ada perencatan dilihat terhadap sel kekal MCF-7 oleh sebahagian fosfat myo-inositol separa tulen daripada dedak padi pada kepekatan <1000 mg/ml. Perencatan MCF-7 hanya dilihat pada kepekatan lebih daripada 30 mg/ml dengan lebih

  15. Quadratic and Cubic Nonlinear Oscillators with Damping and Their Applications

    Science.gov (United States)

    Li, Jibin; Feng, Zhaosheng

    We apply the qualitative theory of dynamical systems to study exact solutions and the dynamics of quadratic and cubic nonlinear oscillators with damping. Under certain parametric conditions, we also consider the van der Waals normal form, Chaffee-Infante equation, compound Burgers-KdV equation and Burgers-KdV equation for explicit representations of kink-profile wave solutions and unbounded traveling wave solutions.

  16. The Number of Real Roots of a Cubic Equation

    Science.gov (United States)

    Kavinoky, Richard; Thoo, John B.

    2008-01-01

    To find the number of distinct real roots of the cubic equation (1) x[caret]3 + bx[caret]2 + cx + d = 0, we could attempt to solve the equation. Fortunately, it is easy to tell the number of distinct real roots of (1) without having to solve the equation. The key is the discriminant. The discriminant of (1) appears in Cardan's (or Cardano's) cubic…

  17. A highly ordered cubic mesoporous silica/graphene nanocomposite

    Science.gov (United States)

    Lee, Chang-Wook; Roh, Kwang Chul; Kim, Kwang-Bum

    2013-09-01

    A highly ordered cubic mesoporous silica (KIT-6)/graphene nanocomposite and 2D KIT-6 nanoflakes were synthesized using a novel synthesis methodology. The non-ionic triblock copolymer, P123, played a dual role as a structure-directing agent in the formation of the cubic mesoporous structure and as a cross-linking agent between mesoporous silica and graphene. The prepared (KIT-6)/graphene nanocomposite could act as a template for the preparation of mesoporous material/graphene nanocomposites.A highly ordered cubic mesoporous silica (KIT-6)/graphene nanocomposite and 2D KIT-6 nanoflakes were synthesized using a novel synthesis methodology. The non-ionic triblock copolymer, P123, played a dual role as a structure-directing agent in the formation of the cubic mesoporous structure and as a cross-linking agent between mesoporous silica and graphene. The prepared (KIT-6)/graphene nanocomposite could act as a template for the preparation of mesoporous material/graphene nanocomposites. Electronic supplementary information (ESI) available: S1: TEM images of disordered mesoporous silica/graphene nanocomposite; S2: TEM images of KIT-6/GO nanocomposite; S3: Thermogravimetric analysis of KIT-6/GO and KG-400-700; S4: SEM and TEM images of KIT-6; S5: Low angle XRD, Raman spectra, N2 adsorption isotherms, pore size distribution and photographic images of the prepared samples; S6: TEM image and N2 adsorption isotherms of mesoporous carbon/graphene nanocomposite; S7: XPS C1s spectra of the prepared samples. See DOI: 10.1039/c3nr03108j

  18. Multiscale Modeling of Point and Line Defects in Cubic Lattices

    Science.gov (United States)

    2007-01-01

    and discli- nations with finite micropolar elastoplasticity . Int. J. Plasticity. 22:210–256, 2006. 56. Menzel, A., and Steinmann, P., On the contin...Voyiadjis, G. Z., A finite strain plastic- damage model for high velocity impact using combined viscosity and gradient localization limiters: Part I...Theoretical for- mulation. Int. J. Damage Mech. 15:293–334, 2006. 58. Milstein, F., and Chantasiriwan, S,. Theoretical study of the response of 12 cubic

  19. INTEGRABILITY AND LINEARIZABILITY FOR A CLASS OF CUBIC KOLMOGOROV SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The integrability and linearizability for a class of cubic Kolmogorov systems are studied. A recursive formula to compute the saddle quantities of the systems is deduced firstly, and integrable conditions for the systems are obtained. Then a recursive formula to compute the coefficients of the normal form for saddle points of the systems is also applied. Finally linearizable conditions of the origin for the systems are given. Both formulas to find necessary conditions are all linear and readily done using c...

  20. Photonic Crystal Cavities in Cubic Polytype Silicon Carbide Films

    CERN Document Server

    Radulaski, Marina; Buckley, Sonia; Rundquist, Armand; Provine, J; Alassaad, Kassem; Ferro, Gabriel; Vučković, Jelena

    2013-01-01

    We present the design, fabrication, and characterization of high quality factor and small mode volume planar photonic crystal cavities from cubic (3C) thin films (thickness ~ 200 nm) of silicon carbide (SiC) grown epitaxially on a silicon substrate. We demonstrate cavity resonances across the telecommunications band, with wavelengths from 1250 - 1600 nm. Finally, we discuss possible applications in nonlinear optics, optical interconnects, and quantum information science.

  1. Infinite Body Centered Cubic Network of Identical Resistors

    CERN Document Server

    Asad, J H

    2013-01-01

    We express the equivalent resistance between the origin and any other lattice site in an infinite Body Centered Cubic (BCC) network consisting of identical resistors each of resistance R rationally in terms of known values and . The equivalent resistance is then calculated. Finally, for large separation between the origin and the lattice site two asymptotic formulas for the resistance are presented and some numerical results with analysis are given.

  2. Lipidic cubic phase injector facilitates membrane protein serial femtosecond crystallography.

    Science.gov (United States)

    Weierstall, Uwe; James, Daniel; Wang, Chong; White, Thomas A; Wang, Dingjie; Liu, Wei; Spence, John C H; Bruce Doak, R; Nelson, Garrett; Fromme, Petra; Fromme, Raimund; Grotjohann, Ingo; Kupitz, Christopher; Zatsepin, Nadia A; Liu, Haiguang; Basu, Shibom; Wacker, Daniel; Han, Gye Won; Katritch, Vsevolod; Boutet, Sébastien; Messerschmidt, Marc; Williams, Garth J; Koglin, Jason E; Marvin Seibert, M; Klinker, Markus; Gati, Cornelius; Shoeman, Robert L; Barty, Anton; Chapman, Henry N; Kirian, Richard A; Beyerlein, Kenneth R; Stevens, Raymond C; Li, Dianfan; Shah, Syed T A; Howe, Nicole; Caffrey, Martin; Cherezov, Vadim

    2014-01-01

    Lipidic cubic phase (LCP) crystallization has proven successful for high-resolution structure determination of challenging membrane proteins. Here we present a technique for extruding gel-like LCP with embedded membrane protein microcrystals, providing a continuously renewed source of material for serial femtosecond crystallography. Data collected from sub-10-μm-sized crystals produced with less than 0.5 mg of purified protein yield structural insights regarding cyclopamine binding to the Smoothened receptor.

  3. Rotary Ultrasonic Machining of Poly-Crystalline Cubic Boron Nitride

    OpenAIRE

    2014-01-01

    Poly-crystalline cubic boron nitride (PCBN) is one of the hardest material. Generally, so hard materials could not be machined by conventional machining methods. Therefore, for this purpose, advanced machining methods have been designed. Rotary ultrasonic machining (RUM) is included among them. RUM is based on abrasive removing mechanism of ultrasonic vibrating diamond particles, which are bonded on active part of rotating tool. It is suitable especially for machining hard and brittle materia...

  4. The traveling salesman problem on cubic and subcubic graphs

    CERN Document Server

    Boyd, Sylvia; van der Ster, Suzanne; Stougie, Leen

    2011-01-01

    We study the Travelling Salesman Problem (TSP) on the metric completion of cubic and subcubic graphs, which is known to be NP-hard. The problem is of interest because of its relation to the famous 4/3 conjecture for metric TSP, which says that the integrality gap, i.e., the worst case ratio between the optimal values of the TSP and its linear programming relaxation (the subtour elimination relaxation), is 4/3. We present the first algorithm for cubic graphs with approximation ratio 4/3. The proof uses polyhedral techniques in a surprising way, which is of independent interest. In fact we prove constructively that for any cubic graph on $n$ vertices a tour of length 4n/3-2 exists, which also implies the 4/3 conjecture, as an upper bound, for this class of graph-TSP. Recently, M\\"omke and Svensson presented a randomized algorithm that gives a 1.461-approximation for graph-TSP on general graphs and as a side result a 4/3-approximation algorithm for this problem on subcubic graphs, also settling the 4/3 conjectur...

  5. Field-effect transistors based on cubic indium nitride.

    Science.gov (United States)

    Oseki, Masaaki; Okubo, Kana; Kobayashi, Atsushi; Ohta, Jitsuo; Fujioka, Hiroshi

    2014-02-04

    Although the demand for high-speed telecommunications has increased in recent years, the performance of transistors fabricated with traditional semiconductors such as silicon, gallium arsenide, and gallium nitride have reached their physical performance limits. Therefore, new materials with high carrier velocities should be sought for the fabrication of next-generation, ultra-high-speed transistors. Indium nitride (InN) has attracted much attention for this purpose because of its high electron drift velocity under a high electric field. Thick InN films have been applied to the fabrication of field-effect transistors (FETs), but the performance of the thick InN transistors was discouraging, with no clear linear-saturation output characteristics and poor on/off current ratios. Here, we report the epitaxial deposition of ultrathin cubic InN on insulating oxide yttria-stabilized zirconia substrates and the first demonstration of ultrathin-InN-based FETs. The devices exhibit high on/off ratios and low off-current densities because of the high quality top and bottom interfaces between the ultrathin cubic InN and oxide insulators. This first demonstration of FETs using a ultrathin cubic indium nitride semiconductor will thus pave the way for the development of next-generation high-speed electronics.

  6. Packing of nonoverlapping cubic particles: Computational algorithms and microstructural characteristics.

    Science.gov (United States)

    Malmir, Hessam; Sahimi, Muhammad; Tabar, M Reza Rahimi

    2016-12-01

    Packing of cubic particles arises in a variety of problems, ranging from biological materials to colloids and the fabrication of new types of porous materials with controlled morphology. The properties of such packings may also be relevant to problems involving suspensions of cubic zeolites, precipitation of salt crystals during CO_{2} sequestration in rock, and intrusion of fresh water in aquifers by saline water. Not much is known, however, about the structure and statistical descriptors of such packings. We present a detailed simulation and microstructural characterization of packings of nonoverlapping monodisperse cubic particles, following up on our preliminary results [H. Malmir et al., Sci. Rep. 6, 35024 (2016)2045-232210.1038/srep35024]. A modification of the random sequential addition (RSA) algorithm has been developed to generate such packings, and a variety of microstructural descriptors, including the radial distribution function, the face-normal correlation function, two-point probability and cluster functions, the lineal-path function, the pore-size distribution function, and surface-surface and surface-void correlation functions, have been computed, along with the specific surface and mean chord length of the packings. The results indicate the existence of both spatial and orientational long-range order as the the packing density increases. The maximum packing fraction achievable with the RSA method is about 0.57, which represents the limit for a structure similar to liquid crystals.

  7. Dry Powder Precursors of Cubic Liquid Crystalline Nanoparticles (cubosomes)

    Science.gov (United States)

    Spicer, Patrick T.; Small, William B.; Small, William B.; Lynch, Matthew L.; Burns, Janet L.

    2002-08-01

    Cubosomes are dispersed nanostructured particles of cubic phase liquid crystal that have stimulated significant research interest because of their potential for application in controlled-release and drug delivery. Despite the interest, cubosomes can be difficult to fabricate and stabilize with current methods. Most of the current work is limited to liquid phase processes involving high shear dispersion of bulk cubic liquid crystalline material into sub-micron particles, limiting application flexibility. In this work, two types of dry powder cubosome precursors are produced by spray-drying: (1) starch-encapsulated monoolein is produced by spray-drying a dispersion of cubic liquid crystalline particles in an aqueous starch solution and (2) dextran-encapsulated monoolein is produced by spray-drying an emulsion formed by the ethanol-dextran-monoolein-water system. The encapsulants are used to decrease powder cohesion during drying and to act as a soluble colloidal stabilizer upon hydration of the powders. Both powders are shown to form (on average) 0.6 μm colloidally-stable cubosomes upon addition to water. However, the starch powders have a broader particle size distribution than the dextran powders because of the relative ease of spraying emulsions versus dispersions. The developed processes enable the production of nanostructured cubosomes by end-users rather than just specialized researchers and allow tailoring of the surface state of the cubosomes for broader application.

  8. Packing of nonoverlapping cubic particles: Computational algorithms and microstructural characteristics

    Science.gov (United States)

    Malmir, Hessam; Sahimi, Muhammad; Tabar, M. Reza Rahimi

    2016-12-01

    Packing of cubic particles arises in a variety of problems, ranging from biological materials to colloids and the fabrication of new types of porous materials with controlled morphology. The properties of such packings may also be relevant to problems involving suspensions of cubic zeolites, precipitation of salt crystals during CO2 sequestration in rock, and intrusion of fresh water in aquifers by saline water. Not much is known, however, about the structure and statistical descriptors of such packings. We present a detailed simulation and microstructural characterization of packings of nonoverlapping monodisperse cubic particles, following up on our preliminary results [H. Malmir et al., Sci. Rep. 6, 35024 (2016), 10.1038/srep35024]. A modification of the random sequential addition (RSA) algorithm has been developed to generate such packings, and a variety of microstructural descriptors, including the radial distribution function, the face-normal correlation function, two-point probability and cluster functions, the lineal-path function, the pore-size distribution function, and surface-surface and surface-void correlation functions, have been computed, along with the specific surface and mean chord length of the packings. The results indicate the existence of both spatial and orientational long-range order as the the packing density increases. The maximum packing fraction achievable with the RSA method is about 0.57, which represents the limit for a structure similar to liquid crystals.

  9. Integer roots of quadratic and cubic polynomials with integer coefficients

    CERN Document Server

    Zelator, Konstantine

    2011-01-01

    The subject matter of this work is quadratic and cubic polynomial functions with integer coefficients;and all of whose roots are integers. The material of this work is directed primarily at educators,students,and teachers of mathematics,grades K12 to K20.The results of this work are expressed in Theorems3,4,and5. Of these theorems, Theorem3, is the one that most likely, the general reader of this article will have some familiarity with.In Theorem3, precise coefficient conditions are given;in order that a quadratic trinomial(with integer) have two integer roots or zeros.On the other hand, Theorems4 and5 are largely unfamiliar territory. In Theorem4, precise coefficient conditions are stated; for a monic cubic polynomial to have a double(i.e.of multiplicity 2) integer root, and a single integer root(i.e.of multiplicity 1).The entire family of such cubics can be described in terms of four groups or subfamilies; each such group being a two-integer parameter subfamily. In Theorem5, a one-integer parameter family o...

  10. Arithmetic Problems in Cubic and Quartic Function Fields

    CERN Document Server

    Bembom, Tobias

    2010-01-01

    One of the main themes in this thesis is the description of the signature of both the infinite place and the finite places in cubic function fields of any characteristic and quartic function fields of characteristic at least 5. For these purposes, we provide a new theory which can be applied to cubic and quartic function fields and to even higher dimensional function fields. One of the striking advantages of this theory to other existing methods is that is does not use the concept of p-adic completions and we can dispense of Cardano's formulae. Another key result comprises the construction of cubic function fields of unit rank 1 and 2, with an obvious fundamental system. One of the main ingredients for such constructions is the definition of the maximum value. This definition is new and very prolific in the context of finding fundamental systems. We conclude the thesis with miscellaneous results on the divisor class number h, including a new approach for finding divisors of h.

  11. Dynamic properties of the cubic nonlinear Schr(o)dinger equation by symplectic method

    Institute of Scientific and Technical Information of China (English)

    Liu Xue-Shen; Wei Jia-Yu; Ding Pei-Zhu

    2005-01-01

    The dynamic properties of a cubic nonlinear Schrodinger equation are investigated numerically by using the symplectic method with different space approximations. The behaviours of the cubic nonlinear Schrodinger equation are discussed with different cubic nonlinear parameters in the harmonically modulated initial condition. We show that the conserved quantities will be preserved for long-time computation but the system will exhibit different dynamic behaviours in space difference approximation for the strong cubic nonlinearity.

  12. Solution of RS232-CAN Converter Based on MCF52259%基于MCF52259的RS232串口-CAN转换器的实现

    Institute of Scientific and Technical Information of China (English)

    郑洪静; 屯娜

    2011-01-01

    The paper proposes to use integrated CAN controller and MCF52259 chip of serial asynchronous transceiver to obtain solution and the software and hardware design based on RS232-CAN converter of the chip.The paper then elaborates on flow control and error control technology in the process of communication.It is tested by multi-function data communication converter system.Results show that the converter has a good performance with real-time communication and error control function.%选用集成CAN控制器以及串行异步收发器的MCF52259芯片,提出基于该芯片的RS232-CAN转换器的解决方案及该转换器的软、硬件设计方案,据此阐述通信过程中的流量控制和差错控制技术.经过多功能数据通讯转换器验证系统的测试,结果表明:转换器具备较好的实时性和错误控制能力,运行状况良好.

  13. PEA3activates CXCL12transcription in MCF-7breast cancer cells%PEA3 activates CXCL12 transcription in MCF-7 breast cancer cells

    Institute of Scientific and Technical Information of China (English)

    CHEN Li; CHEN Bo-bin; LI Jun-jie; JIN Wei; SHAO Zhi-min

    2011-01-01

    Objective To explore the activity of PEA3 ( polyomavirus enhancer activator 3 ) on CXCL12 (Chemokine CXC motif ligand 12) transcription and to reveal the role of PEA3 involved in CXCL12-mediated metastasis and angiogenesis in breast cancer. Methods Methods such as cell transfection, ChIP assay (chromatin immunoprecipitation ), and siRNA (small interfering RNA) were applied to demonstrate and confirm the interaction between PEA3 and CXCL12. Results Over-expression of PEA3 could increase the CXCL12 mRNA level and the CXCL12 promoter activity in human MCF-7 breast cancer cells. ChIP assay demonstrated that PEA3 could bind to the CXCL12 promoter in the cells transfected with PEA3 expression vector. PEA3 siRNA decreased CXCL12 promoter activity and the binding of PEA3 to the CXCL12 promoter in MCF-7 cells. Conclusions PEA3 could activate CXCL12 promoter transcription. It may be a potential mechanism of tumor angiogenesis and metastasis regarding of PEA3 and CXCL12.

  14. Breast cancer cell line MCF7 escapes from G1/S arrest induced by proteasome inhibition through a GSK-3β dependent mechanism.

    Science.gov (United States)

    Gavilán, Elena; Giráldez, Servando; Sánchez-Aguayo, Inmaculada; Romero, Francisco; Ruano, Diego; Daza, Paula

    2015-05-05

    Targeting the ubiquitin proteasome pathway has emerged as a rational approach in the treatment of human cancers. Autophagy has been described as a cytoprotective mechanism to increase tumor cell survival under stress conditions. Here, we have focused on the role of proteasome inhibition in cell cycle progression and the role of autophagy in the proliferation recovery. The study was performed in the breast cancer cell line MCF7 compared to the normal mammary cell line MCF10A. We found that the proteasome inhibitor MG132 induced G1/S arrest in MCF10A, but G2/M arrest in MCF7 cells. The effect of MG132 on MCF7 was reproduced on MCF10A cells in the presence of the glycogen synthase kinase 3β (GSK-3β) inhibitor VII. Similarly, MCF7 cells overexpressing constitutively active GSK-3β behaved like MCF10A cells. On the other hand, MCF10A cells remained arrested after MG132 removal while MCF7 recovered the proliferative capacity. Importantly, this recovery was abolished in the presence of the autophagy inhibitor 3-methyladenine (3-MA). Thus, our results support the relevance of GSK-3β and autophagy as two targets for controlling cell cycle progression and proliferative capacity in MCF7, highlighting the co-treatment of breast cancer cells with 3-MA to synergize the effect of the proteasome inhibition.

  15. Gold nanocatalysts supported on heterostructured PbSO4-MCF mesoporous materials for CO oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Li, Lin [South Central Univ Nationalities China; Tian, Chengcheng [ORNL; Chai, Songhai [ORNL; Binder, Andrew J [ORNL; Brown, Suree [ORNL; Veith, Gabriel M [ORNL; Dai, Sheng [ORNL

    2014-01-01

    Metal oxides are commonly used as the supports of gold nanoparticles for catalytic CO oxidation, whereas metal salts are rarely considered suitable supports. In the present work, we developed a new kind of gold nanocatalyst supported on heterostructured PbSO4-MCF mesoporous materials that was prepared by an in situ growth method using dodecylbenzenesulfonate (SOBS) as a sulfonate precursor. It was found that an Au/PbSO4-MCF (SDBS) catalyst preheated at 300 degrees C showed high CO conversion below 100 degrees C. In addition, the stability of selected catalysts was studied as a function of time on stream. Because of the alteration of surface properties, these Au nanocatalysts were highly sinter-resistant. Published by Elsevier B.V.

  16. HMGB1 silence could promote MCF-7 cell apoptosis and inhibit invasion and metastasis.

    Science.gov (United States)

    Ni, Ping; Zhang, Yongjian; Liu, Yueqin; Lin, Xin; Su, Xiaolian; Lu, Hongxiang; Shen, Huiling; Xu, Wenlin; Xu, Huaxi; Su, Zhaoliang

    2015-01-01

    High mobility group box 1 (HMGB1), a non-histone nuclear protein, was associated with a variety of biological important processes, such as transcription, differentiation, extracellular signaling. As a cytokine or inflammatory mediator, more and more data showed that HMGB1 was involved in inflammatory diseases, cancers or autoimmune disease. However, few data focused on nucleic or cytoplasmic function of HMGB1. Therefore, the present study focused on cancer cells biological characteristics following HMGB1 silence. HMGB1 siRNAs were designed and chemically synthesized, and then transfected into the breast cancer cell line MCF-7 with lipofectamine 2000. The transcription and translation level of HMGB1 expression, proliferation, apoptosis, migration of MCF-7 were determined. The results demonstrated that HMGB1 silence inhibit invasion and migration and promote apoptosis of human breast cells; which indicated that HMGB1 silence might be a potential therapy targets.

  17. Cytotoxicity and genotoxicity assessment of Euphorbia hirta in MCF-7 cell line model using comet assay

    Institute of Scientific and Technical Information of China (English)

    Kwan Yuet Ping; Ibrahim Darah; Yeng Chen; Sreenivasan Sasidharan

    2013-01-01

    Objective:To evaluate the cytotoxicity and genotoxicity activity of Euphorbia hirta (E. hirta) in MCF-7 cell line model using comet assay. Methods: The cytotoxicity of E. hirta extract was investigated by employing brine shrimp lethality assay and the genotoxicity of E. hirta was assessed by using Comet assay. Results: Both toxicity tests exhibited significant toxicity result. In the comet assay, the E. hirta extract exhibited genotoxicity effects against MCF-7 DNA in a time-dependent manner by increasing mean percentage of DNA damage. The extract of E. hirta showed significant toxicity against brine shrimp with an LC50 value of 620.382 μg/mL (24 h). Comparison with positive control potassium dichromate signifies that cytotoxicity exhibited by the methanol extract might have moderate activity. Conclusion:The present work confirmed the cytotoxicity and genotoxicity of E. hirta. However, the observed toxicity of E. hirta extracts needs to be confirmed in additional studies.

  18. Tetrahydro-iso-alpha Acids Antagonize Estrogen Receptor Alpha Activity in MCF-7 Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Maëlle Lempereur

    2016-01-01

    Full Text Available Tetrahydro-iso-alpha acids commonly called THIAA or Tetra are modified hop acids extracted from hop (Humulus lupulus L. which are frequently used in brewing industry mainly in order to provide beer bitterness and foam stability. Interestingly, molecular structure of tetrahydro-iso-alpha acids is close to a new type of estrogen receptor alpha (ERα antagonists aimed at disrupting the binding of coactivators containing an LxxLL motif (NR-box. In this work we show that THIAA decreases estradiol-stimulated proliferation of MCF-7 (ERα-positive breast cancer cells. Besides, we show that it inhibits ERα transcriptional activity. Interestingly, this extract fails to compete with estradiol for ERα binding and does not significantly impact the receptor turnover rate in MCF-7 cells, suggesting that it does not act like classical antiestrogens. Hence, we demonstrate that THIAA is able to antagonize ERα estradiol-induced recruitment of the LxxLL binding motif.

  19. Immobilization of enzyme (DAAO) on hybrid nanoporous MCF, SBA-15, and MCM-41 materials

    Science.gov (United States)

    Phi, Tien Q.; Le, Hy G.; Vu, Tuan A.; Phan, Thao T. H.; Pham, Huyen T.; Dao, Canh Duc; Dang, Phuong T.

    2011-12-01

    Hybrid nanoporous MCF, SBA-15 and MCM-41 materials were synthesized via hydrothermal treatment and functionalized with 3-aminopropyltriethoxysilane (APTES) via post-synthesis grafting and sequently activated by glutardialdehyde and then were used to immobilize D-amino acid oxidase (DAAO). The amino-functionalized materials were characterized by various techniques: XRD, IR and N2 adsorption-desorption (BET). From characterization results, it indicated that these materials still maintained their structure after functionalization. The data IR and TGA-DTA analysis demonstrated the incorpotation of amine functional groups on the surface of APTES-functionalized samples. The DAAO immobilized on functionalized materials exhibited higher catalytic activity and stability for conversion of cephalosporin C (CPC) compare to those of non-functionalized one. Further more, the catalytic activity as well as stability of enzyme decreased in order MCF > SBA-15 > MCM-41 with the decrease of their pore size.

  20. Cytotoxicity of methanol extracts of Elaeis guineensis on MCF-7 and Vero cell lines

    Institute of Scientific and Technical Information of China (English)

    Soundararajan; Vijayarathna; Sreenivasan; Sasidharan

    2012-01-01

    Objective:To investigate the cytotoxic effect of Elaeis guineensis methanol extract on MCF-7and Vero cell.Methods:In vitro cytotoxicity was evaluated in by MTT assay.Cell morphological changes were observed by using light microscope.Results:The MTT assay indicated that methanol extract of the plant exhibited significant cytotoxic effects on MCF-7.Morphological alteration of the cell lines after exposure with lilaeis guineensis extract were observed under phase contrast microscope in the dose dependent manner.Conclusions:The results suggest the probable use of the Elaeis guineensis methanol extract in preparing recipes for cancer-related ailments.Further studies on isolation of metabolites and their in vivo cytotoxicity are under investigation.

  1. Inhibitory effect of substituted dextrans on MCF7 human breast cancer cell growth in vitro.

    Science.gov (United States)

    Morere, J F; Letourneur, D; Planchon, P; Avramoglou, T; Jozefonvicz, J; Israel, L; Crepin, M

    1992-12-01

    Substituted dextrans can reproduce some of the properties of heparin and can thus be used to alter cellular growth. We studied the effect of heparin (H108), dextran (D), carboxymethylbenzylamide dextran (CMDB) and carboxymethylbenzylamide sulfonate dextran (CMDBS) on the growth of human mammary cells of the MCF7 tumor line. The cells were cultured in minimum Eagle's medium containing 2% fetal calf serum without biopolymer, or with increasing concentrations of H108, D, CMDB or CMDBS. Growth curves were accurately based on cell counting using a Coulter counter. Cell distribution in the various phases of the cycle was analyzed by flow cytometry. Dose-dependent growth inhibitory effects (400-4000 micrograms/ml) were observed. The effect on MCF7 tumor cells was most apparent with CMDBS. The percentage of cells in the S phase decreased with preferential blocking in the G0/G1 phase. Pre-clinical studies can be anticipated as there is an absence of in vivo toxicity.

  2. 细胞代谢组学用于木犀草素抑制MCF-7细胞的机制研究%Metabonomics Study on Luteolin Intervention of Breast Cancer MCF-7 Cells

    Institute of Scientific and Technical Information of China (English)

    史栋栋; 王桂明; 况媛媛; 彭章晓; 王彦; 谷雪; 阎超

    2014-01-01

    The metabolic profiles of control and MCF-7 cells treated with luteolin were analyzed separately using gas chromatography/mass spectrometry ( GC/MS ) to study the mechanism of the luteolin treatment on MCF-7 cells. Cell viability assays showed that luteolin had inhibition effect on MCF-7 cells. Partial least square discriminant analysis ( OPLS-DA) was used to process the metabolic data. Since cells in phase of S were increased significantly, we speculated that luteolin had a blocking effect on pentose phosphate pathway of MCF-7 cells, which contributed to its inhibition effect on proliferation of MCF-7 cells.%基于气相色谱质谱联用(GC-MS)技术将代谢组学的方法结合细胞周期的实验,研究木犀草素作用于MCF-7细胞的作用机理。细胞活性实验验证,木犀草素对MCF-7细胞有抑制作用,GC-TOF/MS对加药细胞和未加药细胞代谢物进行指纹图谱分析,并进一步应用偏最小二乘判别分析( OPLS-DA)对代谢组学数据进行多维统计分析。结合木犀草素将细胞周期抑制在S期( Synthesis),推测木犀草素通过阻碍核酸代谢中的磷酸戊糖途径抑制MCF-7细胞的增殖。

  3. Sex differences in relative foot length and perceived attractiveness of female feet: relationships among anthropometry, physique, and preference ratings.

    Science.gov (United States)

    Voracek, Martin; Fisher, Maryanne L; Rupp, Barbara; Lucas, Deanna; Fessler, Daniel M T

    2007-06-01

    Foot size proportionate to stature is smaller in women than in men, and small feet apparently contribute to perceived physical attractiveness of females. This exploratory study investigated the sex difference in relative foot length and interrelations among foot length, physique, and foot preference ratings in samples from Austria and Canada, each comprised of 75 men and 75 women. The findings included the following lines of evidence: the sex difference in relative foot length replicated in both data sets; the magnitude of this sex effect was large. Relative foot length was smaller in young, nulliparous, and slim women. Pointed-toe and high-heel shoes were more likely worn by smaller, lighter, and slimmer women. Men reported liking women's feet in general more than vice versa. A vast majority of both men and women favored small feet in women, but large feet in men. One's own foot size appeared to correspond to evaluations of attractiveness; particularly, women with small feet preferred small feet in women in general. The preference for small feet in women was convergent across different methods of evaluating attractiveness. Directions for investigations in this emerging field of research on physical attractiveness are discussed.

  4. Procyanidin B2 cytotoxicity to MCF-7 human breast adenocarcinoma cells

    Directory of Open Access Journals (Sweden)

    Monalisa M Avelar

    2012-01-01

    Full Text Available Procyanidins have attracted some attention due to their demonstrated chemopreventive action, a relatively new and promising strategy to prevent cancer. Breast cancer is one of the leading causes of death in women worldwide and its treatment needs improvements. The aim of this work was to verify the procyanidin dimmer B2 cytotoxic effect to MCF-7 human breast cancer cells. MCF-7 cells were cultured in RPMI medium, containing 20% fetal bovine serum and antibiotics in a CO 2 chamber. The cells were treated with different concentrations of B2 and its cytotoxic potential was assessed by the sulforhodamine B assay, morphologically through haematoxylin-eosin staining and by DNA fragmentation analysis. The significance of differences between experimental conditions was determined using the ANOVA test, followed by the Tukey test when P<0.05. Cell proliferation decreased in a concentration and time-dependent manner upon procyanidin dimmer B2 treatment, being 19.20 μM the IC 50 . Procyanidin dimmer B2 treatment displayed concentration and time-dependent decline in MCF-7 cells compared to control and also induced morphological alterations compatible with cell-death induction. Cell condensation and cell diameter decreased (3.5 folds compared to control cells, after 48 h cell-exposure to 50 μM procyanidin dimmer B2, but the DNA ladder formation was not observed. In conclusion, our results demonstrated that procyanidin dimmer B2 exhibits cytotoxic activity to MCF-7 cells and it could be a potential antineoplastic agent. Further studies are necessary to clarify the procyanidin dimmer B2 mechanism of action. The evaluation of biological efficacy of individual components is an important step towards drug discovery and development.

  5. Pseudolaric acid B induces apoptosis, senescence, and mitotic arrest in human breast cancer MCF-7

    Institute of Scientific and Technical Information of China (English)

    Jing-hua YU; Qiao CUI; Yuan-yuan JIANG; Wei YANG; Shin-ichi TASHIRO; Satoshi ONODERA; Takashi IKEJIMA

    2007-01-01

    Aim: The aim of the present study was to investigate the inhibitory effect of pseudolaric acid B (PAB) on human breast cancer MCF-7 cells. Methods: 3-(4,5- dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide analysis, morphological changes, acridine orange staining, and agarose gel electrophoresis were applied to detect apoptosis. The percentage of apoptotic and necrotic cells was calcu- lated by the lactate dehydrogenase activity-based cytotoxicity assay; senescence associated (SA)-β-galactosidase activity was detected to evaluate senescence; flow cytometric analysis of propidium iodide staining was carried out to investi- gate the distribution of cell cycle, and the protein expression was examined by Western blot analysis. Results: During apoptosis, the half maximal inhibitory concentration IC502 was 3.4 and 1.35 μmol/L at 36 and 48 h after PAB treatment, respectively. The MCF-7 cells exposed to PAB showed typical characteristics of apoptosis, including the morphological changes and DNA fragmentation. The MCF-7 cells treated with 4 μmol/L PAB for 36 h underwent apoptosis, but not necrosis. The apoptosis induced by PAB was independent of the death receptor pathway. The senescent cells became larger and flatter, and the SA-β-galactosi- dase staining was positive. PAB induced obvious mitotic arrest and it preceded apoptosis and senescence. The expressions of p21 and p53 was upregulated with PAB treatment, and cyclin B 1 was upregulated and transported from the cyto- plasm to nuclei, and sustained stable levels. Conclusion: PAB induced mitotic arrest in the MCF-7 cells and inhibited proliferation through apoptosis and senescence. The apoptosis was independent of the death receptor pathway.

  6. Ligand-specific sequential regulation of transcription factors for differentiation of MCF-7 cells

    Directory of Open Access Journals (Sweden)

    Toyoda Tetsuro

    2009-11-01

    Full Text Available Abstract Background Sharing a common ErbB/HER receptor signaling pathway, heregulin (HRG induces differentiation of MCF-7 human breast cancer cells while epidermal growth factor (EGF elicits proliferation. Although cell fates resulting from action of the aforementioned ligands completely different, the respective gene expression profiles in early transcription are qualitatively similar, suggesting that gene expression during late transcription, but not early transcription, may reflect ligand specificity. In this study, based on both the data from time-course quantitative real-time PCR on over 2,000 human transcription factors and microarray of all human genes, we identified a series of transcription factors which may control HRG-specific late transcription in MCF-7 cells. Results We predicted that four transcription factors including EGR4, FRA-1, FHL2, and DIPA should have responsibility of regulation in MCF-7 cell differentiation. Validation analysis suggested that one member of the activator protein 1 (AP-1 family, FOSL-1 (FRA-1 gene, appeared immediately following c-FOS expression, might be responsible for expression of transcription factor FHL2 through activation of the AP-1 complex. Furthermore, RNAi gene silencing of FOSL-1 and FHL2 resulted in increase of extracellular signal-regulated kinase (ERK phosphorylation of which duration was sustained by HRG stimulation. Conclusion Our analysis indicated that a time-dependent transcriptional regulatory network including c-FOS, FRA-1, and FHL2 is vital in controlling the ERK signaling pathway through a negative feedback loop for MCF-7 cell differentiation.

  7. New 3-Cyano-2-Substituted Pyridines Induce Apoptosis in MCF 7 Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Ahmed Malki

    2016-02-01

    Full Text Available The synthesis of new 3-cyano-2-substituted pyridines bearing various pharmacophores and functionalities at position 2 is described. The synthesized compounds were evaluated for their in vitro anti-cancer activities on five cancer cell lines using 5-FU as reference compound. The results revealed that the benzohydrazide derivative 9a induced growth inhibition in human breast cancer cell line MCF-7 with an IC50 value of 2 μM and it showed lower cytotoxicity on MCF-12a normal breast epithelial cells. Additionally, 9a induced apoptotic morphological changes and induced apoptosis in MCF-7 in a dose and time-dependent manner according to an enzyme linked immunosorbent apoptosis assay which is further confirmed by a TUNEL assay. Flow cytometric analysis indicated that 9a arrested MCF-7 cells in the G1 phase, which was further confirmed by increased expression of p21 and p27 and reduced expression of CDK2 and CDK4. Western blot data revealed significant upregulation of the expression of p53, Bax, caspase-3 and down-regulation of Bcl-2, Mdm-2 and Akt. Additionally, 9a increased the release of cytochrome c from mitochondria to cytoplasm which provokes the mitochondrial apoptotic pathway while it showed no significant change on the expression of the death receptor proteins procaspase-8, caspase-8 and FAS. Furthermore, 9a reduced the expression of phospho AKT and β-catenin in dose dependent manner while inhibiting the expression of migration-related genes such as matrix metalloproteinase (MMP-9 and vascular endothelial growth factor (VEGF. Our findings suggest that compound 9a could be considered as a lead structure for further development of more potent apoptosis inducing agents with anti-metastatic activities.

  8. Acute and chronic cadmium exposure promotes E-cadherin degradation in MCF7 breast cancer cells.

    Science.gov (United States)

    Ponce, Esmeralda; Louie, Maggie C; Sevigny, Mary B

    2015-10-01

    Cadmium is an environmental carcinogen that usually enters the body at minute concentrations through diet or cigarette smoke and bioaccumulates in soft tissues. In past studies, cadmium has been shown to contribute to the development of more aggressive cancer phenotypes including increased cell migration and invasion. This study aims to determine if cadmium exposure-both acute and chronic-contributes to breast cancer progression by interfering with the normal functional relationship between E-cadherin and β-catenin. An MCF7 breast cancer cell line (MCF7-Cd) chronically exposed to 10(-7)  M CdCl2 was previously developed and used as a model system to study chronic exposures, whereas parental MCF7 cells exposed to 10(-6)  M CdCl2 for short periods of time were used to study acute exposures. Cadmium exposure of MCF7 cells led to the degradation of the E-cadherin protein via the ubiquitination pathway. This resulted in fewer E-cadherin/β-catenin complexes and the relocation of active β-catenin to the nucleus, where it interacted with transcription factor TCF-4 to modulate gene expression. Interestingly, only cells chronically exposed to cadmium showed a significant decrease in the localization of β-catenin to the plasma membrane and an increased distance between cells. Our data suggest that cadmium exposure promotes breast cancer progression by (1) down-regulating E-cadherin, thus decreasing the number of E-cadherin/β-catenin adhesion complexes, and (2) enhancing the nuclear translocation of β-catenin to increase expression of cancer-promoting proteins (i.e., c-Jun and cyclin D1).

  9. Evaluation of Cytotoxicity of Sagebrush Plain Extract on Human Breast Cancer MCF7 Cells

    Directory of Open Access Journals (Sweden)

    B Gordanian

    2013-07-01

    Full Text Available Abstract Background & aim: Several studies have reported anti-cancer properties of sagebrush plain. The aim of this study was to evaluate the cytotoxicity of the methanol extract of sagebrush plain on human breast cancer MCF7 cells. Methods: In the present experimental study, the toxic effects of methanol extracts of flowers, leaves, stems and roots of sagebrush plain from of Khorassan and Esfahan province were tested on human breast cancer cells MCF-7 and normal cells HEK293 . Plant samples were extracted by methanol and their toxic effects on normal and breast cancer cells at concentrations of 5.62, 125, 250 and 500 µg/ml was determined by MTT. Both breast cancer cells MCF-7 and normal HEK293 cells were cultured in RPMI-1640 medium and DMEM containing 10% fetal calf serums were cultured. Data were analyzed by one-way ANOVA. Results: The methanol extract of sagebrush showed toxicity on MCF7 cells. The extract of Khorasan showed higher toxicity than Esfahan province. IC50 of sagebrush plant for all parts of the plant were obtained more than 500 µg/ml, but the IC50 of sagebrush plant of Khorasan region in leaf and flower were 205 ± 1.3 and 213 ± 5.3µg respectively. The leaves and flowers in both cases had the highest cytotoxicity. Plant extracts in both regions did not show significant cytotoxicity on normal HEK293 cells. Conclusion: The extract of the sagebrush plain region of Khorasan region showed greater cytotoxicity than Esfahan. It seems that different environmental conditionshas considerable cytotoxicity. Keywords: Sagebrush Plain, MTT, Breast Cancer

  10. Inhibition of SGK1 enhances mAR-induced apoptosis in MCF-7 breast cancer cells.

    Science.gov (United States)

    Liu, Guilai; Honisch, Sabina; Liu, Guoxing; Schmidt, Sebastian; Pantelakos, Stavros; Alkahtani, Saad; Toulany, Mahmoud; Lang, Florian; Stournaras, Christos

    2015-01-01

    Functional membrane androgen receptors (mAR) have previously been described in MCF-7 breast cancer cells. Their stimulation by specific testosterone albumin conjugates (TAC) activate rapidly non-genomic FAK/PI3K/Rac1/Cdc42 signaling, trigger actin reorganization and inhibit cell motility. PI3K stimulates serum and glucocorticoid inducible kinase SGK1, which in turn regulates the function of mAR. In the present study we addressed the role of SGK1 in mAR-induced apoptosis. TAC-stimulated mAR activation elicited apoptosis of MCF-7 cells, an effect significantly potentiated by concomitant incubation of the cells with TAC and the specific SGK1 inhibitors EMD638683 and GSK650394. In line with this, TAC and EMD638683 activated caspase-3. These effects were insensitive to the classical androgen receptor (iAR) antagonist flutamide, pointing to iAR-independent, mAR-induced responses. mAR activation and SGK1 inhibition further considerably augmented the radiation-induced apoptosis of MCF-7 cells. Moreover, TAC- and EMD638683 triggered early actin polymerization in MCF-7 cells. Blocking actin restructuring with cytochalasin B abrogated the TAC- and EMD638683-induced pro-apoptotic responses. Further analysis of the molecular signaling revealed late de-phosphorylation of FAK and Akt. Our results demonstrate that mAR activation triggers pro-apoptotic responses in breast tumor cells, an effect significantly enhanced by SGK1 inhibition, involving actin reorganization and paralleled by down-regulation of FAK/Akt signaling.

  11. Enhanced radiation response in radioresistant MCF-7 cells by targeting peroxiredoxin II

    Directory of Open Access Journals (Sweden)

    Diaz AJG

    2013-10-01

    Full Text Available Anthony Joseph Gomez Diaz,1 Daniel Tamae,2 Yun Yen,3 JianJian Li,4 Tieli Wang1 1Department of Chemistry and Biochemistry, California State University at Dominguez Hills, Carson, CA, 2Center of Excellence in Environmental Toxicology, Department of Pharmacology, University of Pennsylvania, Philadelphia, PA, 3Department of Clinical and Molecular Pharmacology, Beckman Research Institute of City of Hope National Medical Center, Duarte, CA, 4Department of Radiation Oncology, University of California Davis, Sacramento, CA, USA Abstract: In our previous study, we identified that a protein target, peroxiredoxin II (PrxII, is overexpressed in radioresistant MCF+FIR3 breast-cancer cells and found that its expression and function is associated with breast-cancer radiation sensitivity or resistance. Small interference RNA (siRNA targeting PrxII gene expression was able to sensitize MCF+FIR3 radioresistant breast-cancer cells to ionizing radiation. The major focus of this work was to investigate how the radiation response of MCF+FIR3 radioresistant cells was affected by the siRNA that inhibits PrxII gene expression. Our results, presented here, show that silencing PrxII gene expression increased cellular toxicity by altering cellular thiol status, inhibiting Ca2+ efflux from the cells, and perturbing the intracellular Ca2+ homeostasis. By combining radiotherapy and siRNA technology, we hope to develop new therapeutic strategies that may have potential to enhance the efficacy of chemotherapeutic agents due to this technology's property of targeting to specific cancer-related genes. Keywords: siRNA, PrxII, radiation resistance, Ca2+, MCF+FIR3

  12. Effects of hydroxyapatite nanoparticles on proliferation and apoptosis of human breast cancer cells (MCF-7)

    Science.gov (United States)

    Meena, Ramovatar; Kesari, Kavindra Kumar; Rani, Madhu; Paulraj, R.

    2012-02-01

    The study aimed to correlate cell proliferation inhibition with oxidative stress and p53 protein expression in cancerous cells. Hydroxyapatite (HAP) (Ca10(PO4)6(OH)2) is the essential component of inorganic composition in human bone. It has been found to have obvious inhibitory function on growth of many kinds of tumor cells and its nanoparticle has stronger anti-cancerous effect than macromolecule microparticles. Human breast cancer cells (MCF-7) were cultured and treated with HAP nanoparticles at various concentrations. Cells viability was detected with MTT colorimetric assay. The morphology of the cancerous cells was performed by transmission electron microscopy and the expression of a cell apoptosis related gene (p53) was determined by ELISA assay and flow cytometry (FCM). The intracellular reactive oxygen species (ROS) level in HAP exposed cells was measured by H2DCFDA staining. DNA damage was measured by single-cell gel electrophoresis assay. The statistical analysis was done by one way ANOVA. The cellular proliferation inhibition rate was significantly ( p Cell apoptotic characters were observed after MCF-7 cells were treated by HAP nanoparticles for 48 h. Moreover, ELISA assay and FCM shows a dose-dependent activation of p53 in MCF-7 cells treated with nanoHAP. These causative factors of the above results may be justified by an overproduction of ROS. In this study, a significant ( p cells was observed. This study shows that HAP inhibits the growth of human breast cancer MCF-7 cells as well as induces cell apoptosis. This study shows that HAP NPs Induce the production of intracellular reactive oxygen species and activate p53, which may be responsible for DNA damage and cell apoptosis.

  13. Product of aromatase activity in intact LNCaP and MCF-7 human cancer cells.

    Science.gov (United States)

    Castagnetta, L A; Granata, O M; Bellavia, V; Amodio, R; Scaccianoce, E; Notarbartolo, M; Follari, M R; Miceli, M D; Carruba, G

    1997-04-01

    We investigated conversion rates of androgens to estrogens in cultured, hormone-responsive prostate (LNCaP) and breast (MCF-7) human cancer cells. For this purpose, we adopted an intact cell analysis, whereby cells were incubated for different incubation times in the presence of close-to-physiological (1 nM) or supraphysiological (1 microM) concentrations of labelled androgen precursors, i.e. testosterone (T) and androstenedione (delta4Ad). The aromatase activity, as measured by estrogen formation, was detected in LNCaP cells (0.5 pmol/ml), even though to a significantly lower extent than in MCF-7 cells (5.4 pmol/ml), using 1 microM T after 72 h incubation. Surprisingly, LNCaP cells displayed a much higher aromatase activity when T was used as a substrate with respect to delta4Ad. In either cell line, T transformation to delta4Ad was relatively low, attaining only 2.8% in LNCaP and 7.5% MCF-7 cells. However, T was mostly converted to conjugates (over 95%), glucuronides and some sulphates, in LNCaP cells, whereas it was only partly converted to sulphates (<10%) in MCF-7 cells. Aromatase activity seems to be inconsistent in LNCaP cells, being strongly affected by culture conditions, especially by fetal calf serum (FCS). Further studies should assess the regulation of aromatase expression by serum or growth factors in different human cancer cells, also using anti-aromatase and/or anti-estrogen compounds, in different culture conditions.

  14. Nanotoxicity of cobalt induced by oxidant generation and glutathione depletion in MCF-7 cells.

    Science.gov (United States)

    Akhtar, Mohd Javed; Ahamed, Maqusood; Alhadlaq, Hisham A; Alshamsan, Aws

    2017-04-01

    There are very few studies regarding the biological activity of cobalt-based nanoparticles (NPs) and, therefore, the possible mechanism behind the biological response of cobalt NPs has not been fully explored. The present study was designed to explore the potential mechanisms of the cytotoxicity of cobalt NPs in human breast cancer (MCF-7) cells. The shape and size of cobalt NPs were characterized by scanning and transmission electron microscopy (SEM and TEM). The crystallinity of NPs was determined by X-ray diffraction (XRD). The dissolution of NPs was measured in phosphate-buffered saline (PBS) and culture media by atomic absorption spectroscopy (AAS). Cytotoxicity parameters, such as [3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide] (MTT), neutral red uptake (NRU), and lactate dehydrogenase (LDH) release suggested that cobalt NPs were toxic to MCF-7 cells in a dose-dependent manner (50-200μg/ml). Cobalt NPs also significantly induced reactive oxygen species (ROS) generation, lipid peroxidation (LPO), mitochondrial outer membrane potential loss (MOMP), and activity of caspase-3 enzymes in MCF-7 cells. Moreover, cobalt NPs decreased intracellular antioxidant glutathione (GSH) molecules. The exogenous supply of antioxidant N-acetyl cysteine in cobalt NP-treated cells restored the cellular GSH level and prevented cytotoxicity that was also confirmed by microscopy. Similarly, the addition of buthionine-[S, R]-sulfoximine, which interferes with GSH biosynthesis, potentiated cobalt NP-mediated toxicity. Our data suggested that low solubility cobalt NPs could exert toxicity in MCF-7 cells mainly through cobalt NP dissolution to Co(2+). Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Neem Seed Oil Induces Apoptosis in MCF-7 and MDA MB-231 Human Breast Cancer Cells

    Science.gov (United States)

    Sharma, Ramesh; Kaushik, Shweta; Shyam, Hari; Agarwal, Satish; Balapure, Anil Kumar

    2017-08-27

    Background: In traditional Indian medicine, azadirachta indica (neem) is known for its wide range of medicinal properties. Various parts of neem tree including its fruit, seed, bark, leaves, and root have been shown to possess antiseptic, antiviral, antipyretic, anti-inflammatory, antiulcer, antimalarial, antifungal and anticancer activity. Materials and Methods: MCF-7 and MDA MB-231 cells were exposed to various concentrations of 2% ethanolic solution of NSO (1-30 μl/ml) and further processed for cell viability, cell cycle and apoptosis analysis. In addition, cells were analyzed for alteration in Mitochondrial Membrane Potential (MMP) and generation of Reactive Oxygen Species (ROS) using JC-1 and DCFDA staining respectively. Results: NSO give 50% inhibition at 10 μl/ml and 20 μl/ml concentration in MCF-7 and MDA MB-231 cells respectively and, arrests cells at G0/G1 phase in both the cell types. There was a significant alteration in mitochondrial membrane potential that leads to the generation of ROS and induction of apoptosis in NSO treated MCF-7 and MDA MB-231 cells. Conclusion: The results showed that NSO inhibits the growth of human breast cancer cells via induction of apoptosis and G1 phase arrest. Collectively these results suggest that NSO could potentially be used in the management of breast cancer. Creative Commons Attribution License

  16. Effects of ELF magnetic fields on protein expression profile of human breast cancer cell MCF7

    Institute of Scientific and Technical Information of China (English)

    LI Han; ZENG Qunli; WENG Yu; LU Deqiang; JIANG Huai; XU Zhengping

    2005-01-01

    Extremely Low Frequency Magnetic Fields (ELF MF) has been considered as a "possible human carcinogen" by International Agency for Research on Cancer (IARC) while credible mechanisms of its carcinogenicity remain unknown. In this study, a proteomics approach was employed to investigate the changes of protein expression profile induced by ELF MF in human breast cancer cell line MCF7, in order to determine ELF MF-responsive proteins. MCF7 cells were exposed to 50 Hz, 0.4 mT ELF MF for 24 h and the changes of protein profile were examined using two dimensional electrophoresis. Up to 6 spots have been statistically significantly altered (their expression levels were changed at least 5 fold up or down) compared with sham-exposed group. 19 ones were only detected in exposure group while 19 ones were missing. Three proteins were identified by LC-IT Tandem MS as RNA binding protein regulatory subunit、Proteasome subunit beta type 7 precursor and Translationally Controlled Tumor Protein. Our finding showed that 50 Hz, 0.4 mT ELF MF alternates the protein profile of MCF7 cell and may affect many physiological functions of normal cell and 2-DE coupled with MS is a promising approach to elucidating cellular effects of electromagnetic fields.

  17. Differentially expressed proteins in human MCF-7 breast cancer cells sensitive and resistant to paclitaxel.

    Science.gov (United States)

    Pavlíková, Nela; Bartoňová, Irena; Balušíková, Kamila; Kopperova, Dana; Halada, Petr; Kovář, Jan

    2015-04-10

    Resistance of cancer cells to chemotherapeutic agents is one of the main causes of treatment failure. In order to detect proteins potentially involved in the mechanism of resistance to taxanes, we assessed differences in protein expression in MCF-7 breast cancer cells that are sensitive to paclitaxel and in the same cells with acquired resistance to paclitaxel (established in our lab). Proteins were separated using two-dimensional electrophoresis. Changes in their expression were determined and proteins with altered expression were identified using mass spectrometry. Changes in their expression were confirmed using western blot analysis. With these techniques, we found three proteins expressed differently in resistant MCF-7 cells, i.e., thyroid hormone-interacting protein 6 (TRIP6; upregulated to 650%), heat shock protein 27 (HSP27; downregulated to 50%) and cathepsin D (downregulated to 28%). Silencing of TRIP6 expression by specific siRNA leads to decreased number of grown resistant MCF-7 cells. In the present study we have pointed at some new directions in the studies of the mechanism of resistance to paclitaxel in breast cancer cells.

  18. Differential response to α-oxoaldehydes in tamoxifen resistant MCF-7 breast cancer cells.

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    Norbert Nass

    Full Text Available Tamoxifen is the standard adjuvant endocrine therapy for estrogen-receptor positive premenopausal breast cancer patients. However, tamoxifen resistance is frequently observed under therapy. A tamoxifen resistant cell line has been generated from the estrogen receptor positive mamma carcinoma cell line MCF-7 and was analyzed for putative differences in the aldehyde defence system and accumulation of advanced glycation end products (AGE. In comparison to wt MCF-7 cells, these tamoxifen resistant cells were more sensitive to the dicarbonyl compounds glyoxal and methylglyoxal and displayed increased caspase activity, p38-MAPK- and IκBα-phosphorylation. However, mRNA accumulation of the aldehyde- and AGE-defence enzymes glyoxalase-1 and -2 (GLO1, GLO2 as well as fructosamine-3-kinase (FN3K was not significantly altered. Tamoxifen resistant cells contained less free sulfhydryl-groups (glutathione suggesting that the increased sensitivity towards the dicarbonyls was due to a higher sensitivity towards reactive oxygen species which are associated with dicarbonyl stress. To further analyse, if these data are of more general importance, key experiments were replicated with tamoxifen resistant MCF-7 cell lines from two independent sources. These cell lines were also more sensitive to aldehydes, especially glyoxal, but were different in their cellular signalling responses to the aldehydes. In conclusion, glyoxalases and other aldehyde defence enzymes might represent a promising target for the therapy of tamoxifen resistant breast cancers.

  19. Antitumor activity of colloidal silver on MCF-7 human breast cancer cells

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    Franco-Molina Moisés A

    2010-11-01

    Full Text Available Abstract Background Colloidal silver has been used as an antimicrobial and disinfectant agent. However, there is scarce information on its antitumor potential. The aim of this study was to determine if colloidal silver had cytotoxic effects on MCF-7 breast cancer cells and its mechanism of cell death. Methods MCF-7 breast cancer cells were treated with colloidal silver (ranged from 1.75 to 17.5 ng/mL for 5 h at 37°C and 5% CO2 atmosphere. Cell Viability was evaluated by trypan blue exclusion method and the mechanism of cell death through detection of mono-oligonucleosomes using an ELISA kit and TUNEL assay. The production of NO, LDH, and Gpx, SOD, CAT, and Total antioxidant activities were evaluated by colorimetric assays. Results Colloidal silver had dose-dependent cytotoxic effect in MCF-7 breast cancer cells through induction of apoptosis, shown an LD50 (3.5 ng/mL and LD100 (14 ng/mL (*P Conclusions The present results showed that colloidal silver might be a potential alternative agent for human breast cancer therapy.

  20. Gambogic Acid Lysinate Induces Apoptosis in Breast Cancer MCF-7 Cells by Increasing Reactive Oxygen Species

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    Yong-Zhan Zhen

    2015-01-01

    Full Text Available Gambogic acid (GA inhibits the proliferation of various human cancer cells. However, because of its water insolubility, the antitumor efficacy of GA is limited. Objectives. To investigate the antitumor activity of gambogic acid lysinate (GAL and its mechanism. Methods. Inhibition of cell proliferation was determined by MTT assay; intracellular ROS level was detected by staining cells with DCFH-DA; cell apoptosis was determined by flow cytometer and the mechanism of GAL was investigated by Western blot. Results. GAL inhibited the proliferation of MCF-7 cells with IC50 values 1.46 μmol/L comparable with GA (IC50, 1.16 μmol/L. GAL promoted the production of ROS; however NAC could remove ROS and block the effect of GAL. GAL inhibited the expression of SIRT1 but increased the phosphorylation of FOXO3a and the expression of p27Kip1. At knockdown of FOXO3a, cell apoptosis induced by GAL can be partly blocked. In addition it also enhanced the cleavage of caspase-3. Conclusions. GAL inhibited MCF-7 cell proliferation and induced MCF-7 cell apoptosis by increasing ROS level which could induce cell apoptosis by both SIRT1/FOXO3a/p27Kip1 and caspase-3 signal pathway. These results suggested that GAL might be useful as a modulation agent in cancer chemotherapy.

  1. Effects of PP4 suppression on the proliferation of MCF7 cells

    Institute of Scientific and Technical Information of China (English)

    NING Lifeng; LONG Zhitao; HUANG Xiuqing; SUN Lingling; SANG Jianli

    2006-01-01

    PP4, one of the few protein phosphatases associated with centrosome in cells of many species such as Drosophila, C. elegans and mammals, plays an essential role in the regulation of centrosome functions in Drosophila and C. elegans. In order to explore the role of PP4 in mammalian cells, full-length PP4 gene was obtained by RT-PCR from MCF7 cell total RNA and inserted into eukaryotic expression vector pEGFP-C1. The resultant construct pEGFP-C1-PP4 was transfected into MCF7 cells and immunostaining was carried out to confirm the centrosome localization of PP4. Then we reversely subcloned a non-conserved domain of PP4 into pXJ41 to construct an anti-sense vector pXJ41- as-PP4. By transfecting pXJ41-as-PP4 into MCF7 cells and screening with G418, we obtained a stable cell line in which PP4 expression was stably suppressed. The cell line was analyzed on cell morphology, cytoskeleton structure, growth characteristics and the mitosis process. It was found that the proliferation rate decreased and serum-dependence increased in PP4-suppressed cells. Furthermore, flow cytometry and mitotic index analysis showed that G2/M transition was prolonged. PP4 suppression resulted in abnormal interphase microtubule, formation of multipolar spindles and an increase in percentage of multinuclear cells. These results suggested that PP4 is required for centrosome function in mammalian cells.

  2. The influence of calreticulin on oxidative stress i n MCF-7 cells

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    Sree Jaya S

    2014-09-01

    Full Text Available Calreticulin (CRT, a multifunctional protein that regulates varied important cell functions, in addition CRT recently drawn notice that the function of oxidative stress induced apoptosis. At this point, the role of CRT through oxidative stress mediated apoptotic cell death is focused. Herein, we used mammary gland adenocarcinoma cell cells (MCF-7 in vitroto investigate the role CRT overexpression in cell death by promoting ROS induced apoptosis. Human CRT gene was isolated from blood, cDNA was synthesized, CRT was cloned to the XhoI/EcoRI restriction sites of a mammalian expression vector pcDNA 3.1 and plasmid was transfected in to MCF-7 cell line to promote apoptosis. After 24 h and 48 h transfection, cell proliferation, LDH leakage, lipid peroxidation, total protein, and glutathione concentrations were measured. CRT transfected cells expressed higher concentrations of lipid peroxidation and LDHleakage than control MCF -7 cells. There was a significant negative correlation between lipid peroxidation and cell proliferation. Glutathione did not appear to be a significant factor. Therefore, stimulation of CRT may modulate the growth inhibitory effects in human breast cancer cells. One mechanism of growth inhibition may be through increased lipid peroxidation.

  3. Surface enhanced Raman spectroscopy measurements of MCF7 cells adhesion in confined micro-environments

    KAUST Repository

    De Vitis, Stefania

    2015-05-01

    Undoubtedly cells can perceive the external environment, not only from a biochemical point of view with the related signalling pathways, but also from a physical and topographical perspective. In this sense controlled three dimensional micro-structures as well as patterns at the nano-scale can affect and guide the cell evolution and proliferation, due to the fact that the surrounding environment is no longer isotropic (like the flat surfaces of standard cell culturing) but possesses well defined symmetries and anisotropies. In this work regular arrays of silicon micro-pillars with hexagonal arrangement are used as culturing substrates for MCF-7 breast cancer cells. The characteristic size and spacing of the pillars are tens of microns, comparable with MCF-7 cell dimensions and then well suited to induce acceptable external stimuli. It is shown that these cells strongly modify their morphology for adapting themselves to the micro-structured landscape, by means of protrusions from the main body of the cell. Scanning electron microscopy along with both Raman micro-spectroscopy and surface enhanced Raman spectroscopy are used for topographical and biochemical studies of the new cell arrangement. We have revealed that single MCF-7 cells exploit their capability to produce invadopodia, usually generated to invade the neighboring tissue in metastatic activity, for spanning and growing across separate pillars. © 2015 Elsevier Ltd.

  4. Phthalates inhibit tamoxifen-induced apoptosis in MCF-7 human breast cancer cells.

    Science.gov (United States)

    Kim, In Young; Han, Soon Young; Moon, Aree

    2004-12-01

    Environmental estrogens represent a class of compounds that can mimic the function or activity of the endogenous estrogen 17 -estradiol (E2). Phthalates including butyl benzyl phthalate (BBP), di(n-butyl) phthalate (DBP), and di(2-ethylhexyl) phthalate (DEHP) are used as plasticizers, and also widely used in food wraps and cosmetic formulations. Phthalates have been shown to mimic estrogen and are capable of binding to the estrogen receptor (ER). It has been demonstrated that estrogen promotes drug resistance to tamoxifen (TAM) in breast cancer. In order to further evaluate the potential role of the phthalates as environmental estrogens, the effect of phthalates was investigated on TAM-induced apoptosis in MCF-7 human breast cancer cells. Our results show that phthalates, BBP (100 M), DBP (10 M), and DEHP (10 M), significantly increased cell proliferation in MCF-7, but not in MDA-MB-231 cells. In addition, BBP, DBP, and DEHP mimicked estrogen in the inhibition of TAM-induced apoptosis in MCF-7 cells. Our data suggest that the inhibitory effect of phthalates on TAM-induced apoptosis involves an increase in intracellular Bcl-2 to Bax ratio. Given that the phthalates are widely used in cosmetics mainly for women, our findings that revealed the promoting effect of BBP, DBP, and DEHP on chemotherapeutic drug resistance to TAM in breast cancer may be of biological relevance.

  5. Deletion breakpoint mapping on chromosome 9p21 in breast cancer cell line MCF-7

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    Hua-ping XIE

    2012-05-01

    Full Text Available Objective  To map the deletion breakpoint of chromosome 9p21 in breast cancer cell line MCF-7. Methods  The deletion of chromosome 9p21 was checked by Multiplex Ligation-dependent Probe Amplification (MLPA in MCF-7. Subsequently, the deletion breakpoint was amplified by long range PCR and the deletion region was narrowed by primer walking. Finally, the deletion position was confirmed by sequencing. Results  The deletion was found starting within the MTAP gene and ending within CDKN2A gene by MLPA. Based on long range PCR and primer walking, the deletion was confirmed to cover the region from chr9:21819532 to chr9:21989622 by sequencing, with a deletion size of 170kb, starting within the intron 4 of MTAP and ending within the intron 1 near exon 1β of CDKN2A. Conclusions  Long range PCR is an efficient way to detect deletion breakpoints. In MCF-7, the deletion has been confirmed to be 170kb, starting within the MTAP gene and ending within the CDKN2A gene. The significance of the deletion warrants further research.

  6. Modulation of Tamoxifen Cytotoxicity by Caffeic Acid Phenethyl Ester in MCF-7 Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Tarek K. Motawi

    2016-01-01

    Full Text Available Although Tamoxifen (TAM is one of the most widely used drugs in managing breast cancer, many women still relapse after long-term therapy. Caffeic acid phenethyl ester (CAPE is a polyphenolic compound present in many medicinal plants and in propolis. The present study examined the effect of CAPE on TAM cytotoxicity in MCF-7 cells. MCF-7 cells were treated with different concentrations of TAM and/or CAPE for 48 h. This novel combination exerted synergistic cytotoxic effects against MCF-7 cells via induction of apoptotic machinery with activation of caspases and DNA fragmentation, along with downregulation of Bcl-2 and Beclin 1 expression levels. However, the mammalian microtubule-associated protein light chain LC 3-II level was unchanged. Vascular endothelial growth factor level was also decreased, whereas levels of glutathione and nitric oxide were increased. In conclusion, CAPE augmented TAM cytotoxicity via multiple mechanisms, providing a novel therapeutic approach for breast cancer treatment that can overcome resistance and lower toxicity. This effect provides a rationale for further investigation of this combination.

  7. Cherenkov-type diagnostics of fast electrons beams escaping from MCF facilities

    Energy Technology Data Exchange (ETDEWEB)

    Jakubowski, L.; Malinowski, K.; Mirowski, R.; Rabinski, M.; Sadowski, M.J.; Zebrowski, J. [Institute for Nuclear Studies - IPJ, 05-400 Otwock-Swierk (Poland)

    2011-07-01

    The paper presents the feasibility study, the measuring system and the first experimental results of a new method developed for direct detection of high-energy (super-thermal, ripple-born and runaway) electrons generated in magnetic confinement fusion (MCF) facilities. The technique in question is based on registration of the Cherenkov radiation, emitted by energetic electrons, moving through a transparent medium (radiator) with a velocity higher than the velocity of light in this material. The main aim of our studies was to develop a diagnostic technique applicable for measurements of fast electron beams within MCF devices. The IPJ team proposed Cherenkov-type probes because of their high spatial- and temporal-resolutions. The most important results of applications of the presented Cherenkov-type diagnostics have proved that the one- and four-channel versions of the detecting head are useful for studies of the fast (ripple-born and runaway) electrons in different MCF experiments. Experience collected during the described studies allows to introduce some changes in the radiator configuration and to modify the Cherenkov probe design. This document is composed of a paper followed by a poster

  8. Oridonin Loaded Solid Lipid Nanoparticles Enhanced Antitumor Activity in MCF-7 Cells

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    Lu Wang

    2014-01-01

    Full Text Available Oridonin (ORI, a famous diterpenoid from Chinese herbal medicine, has drawn rising attention for its remarkable apoptosis and autophagy-inducing activity in human cancer therapy, while clinical application of ORI is limited by its strong hydrophobicity and rapid plasma clearance. The purpose of this study was to evaluate whether the antitumor activity of ORI could be enhanced by loading into solid lipid nanoparticles (SLNs. ORI-loaded SLNs were prepared by hot high pressure homogenization with narrow size distribution and good entrapment efficacy. MTT assay indicated that ORI-loaded SLNs enhanced the inhibition of proliferation against several human cancer cell lines including breast cancer MCF-7 cells, hepatocellular carcinoma HepG 2 cells, and lung carcinoma A549 cells compared with free ORI, while no significant enhancement of toxicity to human mammary epithelial MCF-10A cells was shown. Meanwhile, flow cytometric analysis demonstrated that ORI-SLNs induced more significant cell cycle arrest at S and decreased cell cycle arrest at G1/G0 phase in MCF-7 cells than bulk ORI solution. Hoechst 33342 staining and Annexin V/PI assay indicated that apoptotic rates of cells treated with ORI-loaded SLNs were higher compared with free ORI. In summary, our data indicated that SLNs may be a potential carrier for enhancing the antitumor effect of hydrophobic drug ORI.

  9. Improved cytotoxicity of pyridyl-substituted thiosemicarbazones against MCF-7 when used as metal ionophores.

    Science.gov (United States)

    Akladios, Fady N; Andrew, Scott D; Parkinson, Christopher J

    2016-02-01

    Zinc is the second most abundant transition metal in the human body, between 3 and 10% of human genes encoding for zinc binding proteins. We have investigated the interplay of reactive oxygen species and zinc homeostasis on the cytotoxicity of the thiosemicarbazone chelators against the MCF-7 cell line. The cytotoxicity of thiosemicarbazone chelators against MCF-7 can be improved through supplementation of ionic zinc provided the zinc ion is at a level exceeding the thiosemicarbazone concentration. Elimination of the entire cell population can be accomplished with this regime, unlike the plateau of cytotoxicity observed on thiosemicarbazone monotherapy. The cytotoxic effects of copper complexes of the thiosemicarbazone are not enhanced by zinc supplementation, displacement of copper from the complex being disfavoured. Treatment of MCF-7 with uncomplexed thiosemicarbazone initiates post G1 blockade alongside the induction of apoptosis, cell death being abrogated through subsequent supplementation with zinc ion after drug removal. This would implicate a metal depletion mechanism in the cytotoxic effect of the un-coordinated thiosemicarbazone. The metal complexes of the species, however, fail to initiate similar G1 blockade and apparently exert their cytotoxic effect through generation of reactive oxygen species, suggesting that multiple mechanisms of cytotoxicity can be associated with the thiosemicarbazones dependant on the level of metal ion association.

  10. Development of the long bones in the hands and feet of children: radiographic and MR imaging correlation

    Energy Technology Data Exchange (ETDEWEB)

    Laor, Tal [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Clarke, Jeffrey P. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Children' s Healthcare of Atlanta, Department of Radiology, Atlanta, GA (United States); Yin, Hong [Children' s Healthcare of Atlanta, Department of Pathology, Atlanta, GA (United States)

    2016-04-15

    The long bones of the hands and feet in children have an epiphyseal end with a secondary center of ossification and an adjacent transverse physis. In contrast to other long bones in the body, the opposite end in the hands and feet, termed the non-epiphyseal end, is characterized by direct metaphyseal extension of bone to complete terminal ossification. The purpose of this pictorial essay is to illustrate the developmental stages of each end of the long bones of the hands and feet with radiographic and MR imaging to provide a foundation from which to differentiate normal from abnormal growth. (orig.)

  11. Rational design of multifunctional micelles against doxorubicin-sensitive and doxorubicin-resistant MCF-7 human breast cancer cells

    Science.gov (United States)

    Hong, Wei; Shi, Hong; Qiao, Mingxi; Gao, Xiang; Yang, Jie; Tian, Chunlian; Zhang, Dexian; Niu, Shengli; Liu, Mingchun

    2017-01-01

    Even though a tremendous number of multifunctional nanocarriers have been developed to tackle heterogeneous cancer cells, little attention has been paid to elucidate how to rationally design a multifunctional nanocarrier. In this study, three individual functions (active targeting, stimuli-triggered release and endo-lysosomal escape) were evaluated in doxorubicin (DOX)-sensitive MCF-7 cells and DOX-resistant MCF-7/ADR cells by constructing four kinds of micelles with active-targeting (AT-M), passive targeting, pH-triggered release (pHT-M) and endo-lysosomal escape (endoE-M) function, respectively. AT-M demonstrated the strongest cytotoxicity against MCF-7 cells and the highest cellular uptake of DOX due to the folate-mediated endocytosis. However, AT-M failed to exhibit the best efficacy against MCF-7/ADR cells, while endoE-M exhibited the strongest cytotoxicity against MCF-7/ADR cells and the highest cellular uptake of DOX due to the lowest elimination of DOX from the cells. This was attributed to the carrier-facilitated endo-lysosomal escape of DOX, which avoided exocytosis by lysosome secretion, resulting in an effective accumulation of DOX in the cytoplasm. The enhanced elimination of DOX from the MCF-7/ADR cells also accounted for the remarkable decrease in cytotoxicity against the cells of AT-M. Three micelles were further evaluated with MCF-7 cells and MCF-7/ADR-resistant cells xenografted mice model. In accordance with the in vitro results, AT-M and endoE-M demonstrated the strongest inhibition on the MCF-7 and MCF-7/ADR xenografted tumor, respectively. Active targeting and active targeting in combination with endo-lysosomal escape have been demonstrated to be the primary function for a nanocarrier against doxorubicin-sensitive and doxorubicin-resistant MCF-7 cells, respectively. These results indicate that the rational design of multifunctional nanocarriers for cancer therapy needs to consider the heterogeneous cancer cells and the primary function needs

  12. Flat feet, happy feet? Comparison of the dynamic plantar pressure distribution and static medial foot geometry between Malawian and Dutch adults.

    Directory of Open Access Journals (Sweden)

    Niki M Stolwijk

    Full Text Available In contrast to western countries, foot complaints are rare in Africa. This is remarkable, as many African adults walk many hours each day, often barefoot or with worn-out shoes. The reason why Africans can withstand such loading without developing foot complaints might be related to the way the foot is loaded. Therefore, static foot geometry and dynamic plantar pressure distribution of 77 adults from Malawi were compared to 77 adults from the Netherlands. None of the subjects had a history of foot complaints. The plantar pressure pattern as well as the Arch Index (AI and the trajectory of the center of pressure during the stance phase were calculated and compared between both groups. Standardized pictures were taken from the feet to assess the height of the Medial Longitudinal Arch (MLA. We found that Malawian adults: (1 loaded the midfoot for a longer and the forefoot for a shorter period during roll off, (2 had significantly lower plantar pressures under the heel and a part of the forefoot, and (3 had a larger AI and a lower MLA compared to the Dutch. These findings demonstrate that differences in static foot geometry, foot loading, and roll off technique exist between the two groups. The advantage of the foot loading pattern as shown by the Malawian group is that the plantar pressure is distributed more equally over the foot. This might prevent foot complaints.

  13. Flat feet, happy feet? Comparison of the dynamic plantar pressure distribution and static medial foot geometry between Malawian and Dutch adults.

    Science.gov (United States)

    Stolwijk, Niki M; Duysens, Jacques; Louwerens, Jan Willem K; van de Ven, Yvonne Hm; Keijsers, Noël Lw

    2013-01-01

    In contrast to western countries, foot complaints are rare in Africa. This is remarkable, as many African adults walk many hours each day, often barefoot or with worn-out shoes. The reason why Africans can withstand such loading without developing foot complaints might be related to the way the foot is loaded. Therefore, static foot geometry and dynamic plantar pressure distribution of 77 adults from Malawi were compared to 77 adults from the Netherlands. None of the subjects had a history of foot complaints. The plantar pressure pattern as well as the Arch Index (AI) and the trajectory of the center of pressure during the stance phase were calculated and compared between both groups. Standardized pictures were taken from the feet to assess the height of the Medial Longitudinal Arch (MLA). We found that Malawian adults: (1) loaded the midfoot for a longer and the forefoot for a shorter period during roll off, (2) had significantly lower plantar pressures under the heel and a part of the forefoot, and (3) had a larger AI and a lower MLA compared to the Dutch. These findings demonstrate that differences in static foot geometry, foot loading, and roll off technique exist between the two groups. The advantage of the foot loading pattern as shown by the Malawian group is that the plantar pressure is distributed more equally over the foot. This might prevent foot complaints.

  14. The structure of the cushions in the feet of African elephants (Loxodonta africana).

    Science.gov (United States)

    Weissengruber, G E; Egger, G F; Hutchinson, J R; Groenewald, H B; Elsässer, L; Famini, D; Forstenpointner, G

    2006-12-01

    The uniquely designed limbs of the African elephant, Loxodonta africana, support the weight of the largest terrestrial animal. Besides other morphological peculiarities, the feet are equipped with large subcutaneous cushions which play an important role in distributing forces during weight bearing and in storing or absorbing mechanical forces. Although the cushions have been discussed in the literature and captive elephants, in particular, are frequently affected by foot disorders, precise morphological data are sparse. The cushions in the feet of African elephants were examined by means of standard anatomical and histological techniques, computed tomography (CT) and magnetic resonance imaging (MRI). In both the forelimb and the hindlimb a 6th ray, the prepollex or prehallux, is present. These cartilaginous rods support the metacarpal or metatarsal compartment of the cushions. None of the rays touches the ground directly. The cushions consist of sheets or strands of fibrous connective tissue forming larger metacarpal/metatarsal and digital compartments and smaller chambers which were filled with adipose tissue. The compartments are situated between tarsal, metatarsal, metacarpal bones, proximal phalanges or other structures of the locomotor apparatus covering the bones palmarly/plantarly and the thick sole skin. Within the cushions, collagen, reticulin and elastic fibres are found. In the main parts, vascular supply is good and numerous nerves course within the entire cushion. Vater-Pacinian corpuscles are embedded within the collagenous tissue of the cushions and within the dermis. Meissner corpuscles are found in the dermal papillae of the foot skin. The micromorphology of elephant feet cushions resembles that of digital cushions in cattle or of the foot pads in humans but not that of digital cushions in horses. Besides their important mechanical properties, foot cushions in elephants seem to be very sensitive structures.

  15. Skeletal pathology and variable anatomy in elephant feet assessed using computed tomography

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    Sophie Regnault

    2017-01-01

    Full Text Available Foot problems are a major cause of morbidity and mortality in elephants, but are underreported due to difficulties in diagnosis, particularly of conditions affecting the bones and internal structures. Here we evaluate post-mortem computer tomographic (CT scans of 52 feet from 21 elephants (seven African Loxodonta africana and 14 Asian Elephas maximus, describing both pathology and variant anatomy (including the appearance of phalangeal and sesamoid bones that could be mistaken for disease. We found all the elephants in our study to have pathology of some type in at least one foot. The most common pathological changes observed were bone remodelling, enthesopathy, osseous cyst-like lesions, and osteoarthritis, with soft tissue mineralisation, osteitis, infectious osteoarthriti, subluxation, fracture and enostoses observed less frequently. Most feet had multiple categories of pathological change (81% with two or more diagnoses, versus 10% with a single diagnosis, and 9% without significant pathology. Much of the pathological change was focused over the middle/lateral digits, which bear most weight and experience high peak pressures during walking. We found remodelling and osteoarthritis to be correlated with increasing age, more enthesopathy in Asian elephants, and more cyst-like lesions in females. We also observed multipartite, missing and misshapen phalanges as common and apparently incidental findings. The proximal (paired sesamoids can appear fused or absent, and the predigits (radial/tibial sesamoids can be variably ossified, though are significantly more ossified in Asian elephants. Our study reinforces the need for regular examination and radiography of elephant feet to monitor for pathology and as a tool for improving welfare.

  16. Skeletal pathology and variable anatomy in elephant feet assessed using computed tomography

    Science.gov (United States)

    Dixon, Jonathon J.I.; Warren-Smith, Chris; Hutchinson, John R.; Weller, Renate

    2017-01-01

    Foot problems are a major cause of morbidity and mortality in elephants, but are underreported due to difficulties in diagnosis, particularly of conditions affecting the bones and internal structures. Here we evaluate post-mortem computer tomographic (CT) scans of 52 feet from 21 elephants (seven African Loxodonta africana and 14 Asian Elephas maximus), describing both pathology and variant anatomy (including the appearance of phalangeal and sesamoid bones) that could be mistaken for disease. We found all the elephants in our study to have pathology of some type in at least one foot. The most common pathological changes observed were bone remodelling, enthesopathy, osseous cyst-like lesions, and osteoarthritis, with soft tissue mineralisation, osteitis, infectious osteoarthriti, subluxation, fracture and enostoses observed less frequently. Most feet had multiple categories of pathological change (81% with two or more diagnoses, versus 10% with a single diagnosis, and 9% without significant pathology). Much of the pathological change was focused over the middle/lateral digits, which bear most weight and experience high peak pressures during walking. We found remodelling and osteoarthritis to be correlated with increasing age, more enthesopathy in Asian elephants, and more cyst-like lesions in females. We also observed multipartite, missing and misshapen phalanges as common and apparently incidental findings. The proximal (paired) sesamoids can appear fused or absent, and the predigits (radial/tibial sesamoids) can be variably ossified, though are significantly more ossified in Asian elephants. Our study reinforces the need for regular examination and radiography of elephant feet to monitor for pathology and as a tool for improving welfare. PMID:28123909

  17. Regulation of SAHA on cell proliferation induced by leptin in breast cancer cell line MCF-7%SAHA在Leptin诱导的乳腺癌MCF-7细胞增殖过程中的调控作用

    Institute of Scientific and Technical Information of China (English)

    冯秀艳; 韩翰; 周伟强

    2016-01-01

    To clarify the molecular mechanism of SAHA in the cell proliferation of ER-positive breast cancer cell line MCF-7 induced by leptin. Methods Human breast cancer cell MCF-7 was incubated with SAHA and/or leptin, and cell viability, apoptosis and cell cy-cle of MCF-7 cells were detected by Muse Cell Analy-zer. The expression of proteins related with apoptosis was determined by apotosis antibody array. Results Real-time cell proliferation assays indicated that the in-duction effect of leptin for MCF-7 cells reached the peak at a concentration of 0. 625 nmol · L-1 . SAHA reduced the viability of MCF-7 cells, induced G0/G1 phase arrest in the cell cycle, and triggered the apopto-sis. Meanwhile, SAHA significantly induced the pro-tein expressions of some apoptotic factors, including Bax, Caspase-3, TRAIL DR5, p21CIP1, and inhibited the expressions of Claspin, Clusterin, x-linked inhibi-tor of apoptosis protein(XIAP) and survivin. Howev-er, leptin had reverse effects on the related expression of the proteins. Conclusion The effects of cell prolif-eration by leptin and SAHA treatment in breast cancer ER positive cell line MCF-7 may involve in the activa-tion of apoptosis pathway, in particular with releasing of Caspase-3 trigged by endogenous mitochondrial ap-optosis pathway.%目的:为了阐明SAHA调控Leptin诱导的乳腺癌ER+细胞系MCF-7细胞增殖的分子机制,我们采用实时无标记细胞分析系统,动态监测Leptin对MCF-7细胞生长状况的影响。方法通过自动细胞分析仪Muse Cell Analyzer分析Leptin和SAHA对MCF-7细胞活力、细胞凋亡以及细胞周期产生的影响,并应用细胞凋亡抗体芯片测定Leptin和SAHA两种处理因素作用MCF-7细胞后相关凋亡通路分子表达变化的情况。结果低浓度Leptin对MCF-7细胞生长有诱导作用,其浓度为0.625 nmol·L-1时作用效果最明显。细胞分析结果表明, SAHA能明显抑制Leptin诱导的MCF-7细胞增殖,经SAHA处理后MCF-7细胞活力明

  18. The Inhibitory Action of Resveratrol on Proliferation of MCF-7 Breast Cancer Cells%白藜芦醇抑制MCF-7乳腺癌细胞增殖的机制研究

    Institute of Scientific and Technical Information of China (English)

    郭慧琳; 张献全

    2011-01-01

    Objective: To investigate the inhibitory action of resveratrol on the proliferation of MCF-7 breast cancer cells and its underlying mechanisms. Methods: Human MCF-7 breast cancer cells were used and stimulated with resveratrol. The proliferation of MCF-7 breast cancer cells was determined using MTT assay. The changes in proliferation rate were also observed in cells co-stimulated with PD98059, an ERK1/2 inhibitor, and resveratrol. The effects of resveratrol expression on ERK1/2, p-ERKl/2, AKT, and p-AKT in the MCF-7 cancer cells were determined using immunoblotting. Results: The proliferation of MCF-7 breast cancer cells was obviously inhibited by resveratrol in a concentration-dependent manner. The inhibitory action of resveratrol on the MCF-7 cells was overtly repressed by PD98059. At the same time, resveratrol apparently increased p-ERKl/2 protein expression and decreased p-AKT protein expression. However, there was no change in the level of ERK1/2 and AKT protein expression after the resveratrol stimulation. Conclusion: Resveratrol effectively inhibits the proliferation of MCF-7 breast cancer cells, and its inhibitory action is through the regulation of the ERK1/2 and AKT signal pathway.%目的:研究白藜芦醇对MCF-7乳腺癌细胞抑制效应及其作用机制.方法:以人MCF-7乳腺癌细胞株为研究对象,利用MTT方法研究白藜芦醇抑制MCF-7乳腺癌细胞的生物学效应;观察在ERK1/2抑制剂PD98059预处理情况下,白藜芦醇抑制MCF-7乳腺癌细胞增殖效应的改变;利用免疫印迹方法观察白藜芦醇对MCF-7乳腺癌细胞中ERK1/2与AKT信号分子的蛋白表达.结果:白藜芦醇能够明显降低MCF-7乳腺癌细胞增殖能力,该作用呈一定的浓度依赖性关系.在ERK1/2抑制剂PD98059预处理情况下,白藜芦醇对MCF-7乳腺癌细胞增殖抑制效应能明显抑制,PD98059可明显减轻该效应.同时,白藜芦醇明显增加p-ERK1/2蛋白表达,降低p-AKT表达水平,但对ERK1/2与AKT蛋白

  19. Xanthohumol, a Prenylated Chalcone from Hops, Inhibits the Viability and Stemness of Doxorubicin-Resistant MCF-7/ADR Cells

    OpenAIRE

    Ming Liu; Hua Yin; Xiaokun Qian; Jianjun Dong; Zhonghua Qian; Jinlai Miao

    2016-01-01

    Xanthohumol is a unique prenylated flavonoid in hops (Humulus lupulus L.) and beer. Xanthohumol has been shown to possess a variety of pharmacological activities. There is little research on its effect on doxorubicin-resistant breast cancer cells (MCF-7/ADR) and the cancer stem-like cells exiting in this cell line. In the present study, we investigate the effect of xanthohumol on the viability and stemness of MCF-7/ADR cells. Xanthohumol inhibits viability, induces apoptosis, and arrests the ...

  20. Induction of apoptosis in MCF-7 cells by β-1,3-xylooligosaccharides prepared from Caulerpa lentillifera.

    Science.gov (United States)

    Maeda, Reiko; Ida, Tomoaki; Ihara, Hideshi; Sakamoto, Tatsuji

    2012-01-01

    β-1,3-Xylan was prepared from the green alga, Caulerpa lentillifera, and hydrolyzed to oligosaccharides by a mild acid treatment. The average degree of polymerization was about 5. The oligosaccharides reduced the number of viable human breast cancer MCF-7 cells in a dose-dependent manner, and induced chromatin condensation and degradation of poly ADP-ribose polymerase, indicating that they induced apoptosis in MCF-7 cells.

  1. Design of a New Propulsion Mechanism of Imitating Duck’s Webbed-feet

    Directory of Open Access Journals (Sweden)

    Yuan Dai

    2013-08-01

    Full Text Available With the wide application of the underwater vehicle in ocean exploration, bionics propulsion aroused intensive interest among researchers. Bionic locomotion of aquatic animals has the advantages of highly maneuver, power-efficient endurance and so on. In the paper the mechanism of duck’s swimming is studied and a novel bionics propulsion mechanism is designed and analyzed. The mechanics of underwater vehicle is investigated by ADAMS. Dynamics response of the system is analyzed by using numerical method. The simulation results suggest that the designed propulsion mechanism can imitate the movement modes of the duck’s webbed feet, and implement the motion of vehicle in fluid environment.

  2. In vitro evaluation of anticancer potentials of lupeol isolated from Elephantopus scaber L. on MCF-7 cell line

    Directory of Open Access Journals (Sweden)

    Daisy Pitchai

    2014-01-01

    Full Text Available Lupeol is a triterpenoid, present in most of the medicinally effective plants and possess a wide range of biological activity against human diseases. The present study aims at evaluating the anticancer potentials of lupeol, isolated from the leaves of Elephantopus scaber L. and thereby explores its action on key cancer marker, Bcl-2. The effect of lupeol on the cell viability of MCF-7 was determined by MTT and lactate dehydrogenase assays at different concentrations. The efficacy of the compound to induce cell death was analyzed using AO/EtBr staining. Phase contrast microscopic analysis provided the changes in cell morphology of the compound treated normal breast cells (MCF-10A and MCF-7 cells. The expression of Bcl-2 and Bcl-xL proteins in the normal, cancer and lupeol treated cancer cell was analyzed by western blotting. Lupeol induced an effective change in the cell viability of MCF-7 cells with IC 50 concentration as 80 μM. Induction of cell death, change in cell morphology and population of the cancer cells was observed in the lupeol treated cells, but the normal cells were not affected. The compound effectively downregulated Bcl-2 and Bcl-xL protein expressions, which directly contribute for the induction of MCF-7 cell apoptosis. Conclusion: Thus, lupeol acts as an anticancer agent against MCF-7 cells and is a potent phytodrug to be explored further for its cytotoxic mechanism.

  3. In situ synthesized BSA capped gold nanoparticles: effective carrier of anticancer drug methotrexate to MCF-7 breast cancer cells.

    Science.gov (United States)

    Murawala, Priyanka; Tirmale, Amruta; Shiras, Anjali; Prasad, B L V

    2014-01-01

    The proficiency of MTX loaded BSA capped gold nanoparticles (Au-BSA-MTX) in inhibiting the proliferation of breast cancer cells MCF-7 as compared to the free drug Methotrexate (MTX) is demonstrated based on MTT and Ki-67 proliferation assays. In addition, DNA ladder gel electrophoresis studies, flow cytometry and TUNEL assay confirmed the induction of apoptosis by MTX and Au-BSA-MTX in MCF-7 cells. Notably, Au-BSA-MTX was found to have higher cytotoxicity on MCF-7 cells compared with an equivalent dose of free MTX. The enhanced activity is attributed to the preferential uptake of Au-BSA-MTX particles by MCF-7 cells due to the presence of BSA that acts as a source of nutrient and energy to the rapidly proliferating MCF-7 cells. Moreover, the targeting ability of the drug MTX to the over expressed folate receptors on MCF-7 cells also contributes to the enhanced uptake and activity. Taken together, these results unveil that Au-BSA-MTX could be more effective than free drug for cancer treatment.

  4. Determination of the estrogenic activity of wild phytoestrogen-rich Pueraria mirifica by MCF-7 proliferation assay.

    Science.gov (United States)

    Cherdshewasart, Wichai; Traisup, Virasinee; Picha, Porntipa

    2008-02-01

    The aim of this study was to evaluate the estrogenic activity of tuberous samples of wild, phytoestrogen-rich Pueraria mirifica collected from 28 out of 76 provinces of Thailand by MCF-7 proliferation assay. The plant extracts were administered to MCF-7, ER alpha positive human mammary adenocarcinoma cell cultures, for 3 days at dosages of 0.1, 1, 10, 100 and 1,000 microg/ml and were compared with 17 beta-estradiol at concentrations of 10(-12)-10(-6) M. The mean P. mirifica population at 1 mug/ml exhibited significant proliferation. Two plant samples exhibited levels of proliferation in MCF-7 that were similar to 17beta-estradiol. The mean P. mirifica populations at 100 and 1,000 microg/ml exhibited significant cytotoxicity in MCF-7. Analysis of the estrogenic activity of puerarin, representative of major isoflavonoids in P. mirifica tubers, revealed proliferation in MCF-7 only at the highest dose (10(-6) M) that was 10(2)-10(5) times less active than 17 beta-estradiol. Puerarin and 17 beta-estradiol at concentration of 10(-12)-10(-6) M exhibited no cytotoxicity in MCF-7.

  5. The Effect of Particles on Electrolytically Polymerized Thin Natural MCF Rubber for Soft Sensors Installed in Artificial Skin

    Directory of Open Access Journals (Sweden)

    Kunio Shimada

    2017-04-01

    Full Text Available The aim of this study is to investigate the effect of particles as filler in soft rubber sensors installed in artificial skin. We examine sensors made of natural rubber (NR-latex that include magnetic particles of Ni and Fe3O4 using magnetic compound fluid (MCF. The 1-mm thickness of the electrolytically polymerized MCF rubber makes production of comparatively thin rubber sensors feasible. We first investigate the effect of magnetic particles Ni and Fe3O4 on the curing of MCF rubber. Next, in order to adjust the electric properties of the MCF rubber, we adopt Al2O3 dielectric particles. We investigate the effect of Al2O3 particles on changes in electric current, voltage and temperature of electrolytically polymerized MCF rubber liquid, and on the electric properties under the application of normal and shear forces. By adjusting the ratio of Ni, Fe3O4, Al2O3 and water in MCF rubber with Al2O3, it is possible to change the electric properties.

  6. Quantitative estimation of the state of vault feet gymnasts on the different stages of the long-term training

    Directory of Open Access Journals (Sweden)

    Makarova O.V.

    2013-10-01

    Full Text Available The analysis of the vaults given about the state is conducted feet gymnasts on the different stages of the long-term training. 93 sportswomen of different qualification took part in research. The system of Big foot was used. It is set that on the early stages of the long-term training for gymnasts observed flattening heights of unevenness of navicular bone above the floor. With growth of qualification of sportswomen to avoid development of pathological changes of vaults feet actually not possibly. It is conditioned the rules of competitions to complication of competition compositions and technique of execution of elements of calisthenics. It is marked that appearance of flattening feet requires: corrections in the system of training; introduction of the specially developed methods on the removal of existent deformations; prophylaxis of flat-footedness; strengthening of musculoskeletal system feet.

  7. Vacancy-induced mechanical stabilization of cubic tungsten nitride

    Science.gov (United States)

    Balasubramanian, Karthik; Khare, Sanjay; Gall, Daniel

    2016-11-01

    First-principles methods are employed to determine the structural, mechanical, and thermodynamic reasons for the experimentally reported cubic WN phase. The defect-free rocksalt phase is both mechanically and thermodynamically unstable, with a negative single crystal shear modulus C44=-86 GPa and a positive enthalpy of formation per formula unit Hf=0.623 eV with respect to molecular nitrogen and metallic W. In contrast, WN in the NbO phase is stable, with C44=175 GPa and Hf=-0.839 eV . A charge distribution analysis reveals that the application of shear strain along [100] in rocksalt WN results in an increased overlap of the t2 g orbitals which causes electron migration from the expanded to the shortened W-W bond axes, yielding a negative shear modulus due to an energy reduction associated with new bonding states 8.1-8.7 eV below the Fermi level. A corresponding shear strain in WN in the NbO phase results in an energy increase and a positive shear modulus. The mechanical stability transition from the NaCl to the NbO phase is explored using supercell calculations of the NaCl structure containing Cv=0 %-25 % cation and anion vacancies, while keeping the N-to-W ratio constant at unity. The structure is mechanically unstable for Cvconcentration, the isotropic elastic modulus E of cubic WN is zero, but increases steeply to E =445 GPa for Cv=10 % , and then less steeply to E =561 GPa for Cv=25 % . Correspondingly, the hardness estimated using Tian's model increases from 0 to 15 to 26 GPa as Cv increases from 5% to 10% to 25%, indicating that a relatively small vacancy concentration stabilizes the cubic WN phase and that the large variations in reported mechanical properties of WN can be attributed to relatively small changes in Cv.

  8. Cubic Phases, Cubosomes and Ethosomes for Cutaneous Application.

    Science.gov (United States)

    Esposito, Elisabetta; Drechsler, Markus; Nastruzzi, Claudio; Cortesi, Rita

    2016-01-01

    Cutaneous administration represents a good strategy to treat skin diseases, avoiding side effects related to systemic administration. Apart from conventional therapy, based on the use of semi-solid formulation such as gel, ointments and creams, recently the use of specialized delivery systems based on lipid has been taken hold. This review provides an overview about the use of cubic phases, cubosomes and ethosomes, as lipid systems recently proposed to treat skin pathologies. In addition in the final part of the review cubic phases, cubosomes and ethosomes are compared to solid lipid nanoparticles and lecithin organogel with respect to their potential as delivery systems for cutaneous application. It has been reported that lipid nanosystems are able to dissolve and deliver active molecules in a controlled fashion, thereby improving their bioavailability and reducing side-effects. Particularly lipid matrixes are characterized by skin affinity and biocompatibility allowing their application on skin. Indeed, after cutaneous administration, the lipid matrix of cubic phases and cubosomes coalesces with the lipids of the stratum comeum and leads to the formation of a lipid depot from which the drug associated to the nanosystem can be released in the deeper skin strata in a controlled manner. Ethosomes are characterized by a malleable structure that promotes their interaction with skin, improving their potential as skin delivery systems with respect to liposomes. Also in the case of solid lipid nanoparticles it has been suggested a deep interaction between lipid matrix and skin strata that endorses sustained and prolonged drug release. Concerning lecithin organogel, the peculiar structure of this system, where lecithin exerts a penetration enhancer role, allows a deep interaction with skin strata, promoting the transdermal absorption of the encapsulated drugs.

  9. Nuclear β-catenin and CD44 upregulation characterize invasive cell populations in non-aggressive MCF-7 breast cancer cells

    Directory of Open Access Journals (Sweden)

    Uchino Masahiro

    2010-08-01

    Full Text Available Abstract Background In breast cancer cells, the metastatic cell state is strongly correlated to epithelial-to-mesenchymal transition (EMT and the CD44+/CD24- stem cell phenotype. However, the MCF-7 cell line, which has a luminal epithelial-like phenotype and lacks a CD44+/CD24- subpopulation, has rare cell populations with higher Matrigel invasive ability. Thus, what are the potentially important differences between invasive and non-invasive breast cancer cells, and are the differences related to EMT or CD44/CD24 expression? Methods Throughout the sequential selection process using Matrigel, we obtained MCF-7-14 cells of opposite migratory and invasive capabilities from MCF-7 cells. Comparative analysis of epithelial and mesenchymal marker expression was performed between parental MCF-7, selected MCF-7-14, and aggressive mesenchymal MDA-MB-231 cells. Furthermore, using microarray expression profiles of these cells, we selected differentially expressed genes for their invasive potential, and performed pathway and network analysis to identify a set of interesting genes, which were evaluated by RT-PCR, flow cytometry or function-blocking antibody treatment. Results MCF-7-14 cells had enhanced migratory and invasive ability compared with MCF-7 cells. Although MCF-7-14 cells, similar to MCF-7 cells, expressed E-cadherin but neither vimentin nor fibronectin, β-catenin was expressed not only on the cell membrane but also in the nucleus. Furthermore, using gene expression profiles of MCF-7, MCF-7-14 and MDA-MB-231 cells, we demonstrated that MCF-7-14 cells have alterations in signaling pathways regulating cell migration and identified a set of genes (PIK3R1, SOCS2, BMP7, CD44 and CD24. Interestingly, MCF-7-14 and its invasive clone CL6 cells displayed increased CD44 expression and downregulated CD24 expression compared with MCF-7 cells. Anti-CD44 antibody treatment significantly decreased cell migration and invasion in both MCF-7-14 and MCF-7-14 CL6

  10. Comparison of plantar pressure distribution in subjects with normal and flat feet during gait

    Directory of Open Access Journals (Sweden)

    Aluisio Otavio Vargas Avila

    2010-06-01

    Full Text Available The aim of this study was to determine the possible relationship between loss of thenormal medial longitudinal arch measured by the height of the navicular bone in a static situationand variables related to plantar pressure distribution measured in a dynamic situation. Elevenmen (21 ± 3 years, 74 ± 10 kg and 175 ± 4 cm participated in the study. The Novel Emed-ATSystem was used for the acquisition of plantar pressure distribution data (peak pressure, meanpressure, contact area, and relative load at a sampling rate of 50 Hz. The navicular drop testproposed by Brody (1982 was used to assess the height of the navicular bone for classificationof the subjects. The results were compared by the Mann-Whitney U test, with the level of significanceset at p ≤ 0.05. Differences were observed between the two groups in the mid-foot regionfor all variables studied, with the observation of higher mean values in subjects with flat feet.There were also significant differences in contact area, relative load, peak pressure, and meanpressure between groups. The present study demonstrates the importance of paying attentionto subjects with flat feet because changes in plantar pressure distribution are associated withdiscomfort and injuries.

  11. Precise and feasible measurements of lateral calcaneal lengthening osteotomies by radiostereometric analysis in cadaver feet

    Science.gov (United States)

    Martinkevich, P.; Rahbek, O.; Møller-Madsen, B.; Søballe, K.; Stilling, M.

    2015-01-01

    Objectives Lengthening osteotomies of the calcaneus in children are in general grafted with bone from the iliac crest. Artificial bone grafts have been introduced, however, their structural and clinical durability has not been documented. Radiostereometric analysis (RSA) is a very accurate and precise method for measurements of rigid body movements including the evaluation of joint implant and fracture stability, however, RSA has not previously been used in clinical studies of calcaneal osteotomies. We assessed the precision of RSA as a measurement tool in a lateral calcaneal lengthening osteotomy (LCLO). Methods LCLO was performed in six fixed adult cadaver feet. Tantalum markers were inserted on each side of the osteotomy and in the cuboideum. Lengthening was done with a plexiglas wedge. A total of 24 radiological double examinations were obtained. Two feet were excluded due to loose and poorly dispersed markers. Precision was assessed as systematic bias and 95% repeatability limits. Results Systematic bias was generally below 0.10 mm for translations. Precision of migration measurements was below 0.2 mm for translations in the osteotomy. Conclusion RSA is a precise tool for the evaluation of stability in LCLO. Cite this article: Bone Joint Res 2015;4:78–83. PMID:25957380

  12. The Effect of Foot Orthoses on Energy Consumption in Runners with Flat Feet

    Directory of Open Access Journals (Sweden)

    Farzad Farmani

    2010-01-01

    Full Text Available Introduction Foot orthosis is used as protective treatment in people with flatfoot. This study aimed at assessing the effects of Foot orthosis on energy consumption in 20 runners with flat feet.Methods: In this study a treadmill and a Quark b2 were used to measure oxygen consumption. For each patient, a pair of foot orthosis with the appropriate size was prepared. The maximum running Heart rate, vo2 max and vo2 of the subjects were measured and calculated with and without foot orthoses. The data were compared through paired T-test.Results: In this study, after using the foot orthoses, the mean VO2 (ML/M, theVO2 max (ML/M for each Kg of body weight and the maximum heart rate respectively reduced from 4504.6 to 4488.3, from 63.6 to 63.4 and from 168.7 to 168.0, all of which indicating a significant observed reduction (P<0.05.Conclusion: Foot support devices (orthoses result in realignment of lower extremity joints in patients with flat feet, thus length- tension relationship of muscles improve. This prevents muscle fatigue in long- distance running. Finally, when suitable foot orthoses was applied energy consumption during running decreased.

  13. Mapping sea urchins tube feet proteome--a unique hydraulic mechano-sensory adhesive organ.

    Science.gov (United States)

    Santos, Romana; Barreto, Angela; Franco, Catarina; Coelho, Ana Varela

    2013-02-21

    Marine organisms secrete adhesives for substrate attachment that to be effective require functional assembly underwater and displacement of water, ions, and weakly bound polyions that are ubiquitous in seawater. Therefore, understanding the characteristics of these protein/carbohydrate-based marine adhesives is imperative to decipher marine adhesion and also, to accelerate the development of new biomimetic underwater adhesives and anti-fouling agents. The present study, aims at mapping the proteome of the sea urchin Paracentrotus lividus adhesive organs using a combination of complementary protein separation techniques (1-D-nanoLC and 2-DE), databases and search algorithms. This strategy resulted in the identification of 328 non-redundant proteins, constituting the first comprehensive list of sea urchin tube feet proteins. Given the known importance of phosphorylation and glycosylation in marine adhesion, the 2DE proteome was re-analyzed with specific fluorescent stains for these two PTMs, resulting in the identification of 69 non-redundant proteins. The obtained results demonstrate that tube feet are unique mechano-sensory adhesive organs and highlight putative adhesive proteins, that although requiring further confirmation, constitute a step forward in the quest to decipher sea urchins temporary adhesion.

  14. Molecular shifts in limb identity underlie development of feathered feet in two domestic avian species

    Science.gov (United States)

    Domyan, Eric T; Kronenberg, Zev; Infante, Carlos R; Vickrey, Anna I; Stringham, Sydney A; Bruders, Rebecca; Guernsey, Michael W; Park, Sungdae; Payne, Jason; Beckstead, Robert B; Kardon, Gabrielle; Menke, Douglas B; Yandell, Mark; Shapiro, Michael D

    2016-01-01

    Birds display remarkable diversity in the distribution and morphology of scales and feathers on their feet, yet the genetic and developmental mechanisms governing this diversity remain unknown. Domestic pigeons have striking variation in foot feathering within a single species, providing a tractable model to investigate the molecular basis of skin appendage differences. We found that feathered feet in pigeons result from a partial transformation from hindlimb to forelimb identity mediated by cis-regulatory changes in the genes encoding the hindlimb-specific transcription factor Pitx1 and forelimb-specific transcription factor Tbx5. We also found that ectopic expression of Tbx5 is associated with foot feathers in chickens, suggesting similar molecular pathways underlie phenotypic convergence between these two species. These results show how changes in expression of regional patterning genes can generate localized changes in organ fate and morphology, and provide viable molecular mechanisms for diversity in hindlimb scale and feather distribution. DOI: http://dx.doi.org/10.7554/eLife.12115.001 PMID:26977633

  15. Superhydrophobic gecko feet with high adhesive forces towards water and their bio-inspired materials

    Science.gov (United States)

    Liu, Kesong; Du, Jiexing; Wu, Juntao; Jiang, Lei

    2012-01-01

    Functional integration is an inherent characteristic for multiscale structures of biological materials. In this contribution, we first investigate the liquid-solid adhesive forces between water droplets and superhydrophobic gecko feet using a high-sensitivity micro-electromechanical balance system. It was found, in addition to the well-known solid-solid adhesion, the gecko foot, with a multiscale structure, possesses both superhydrophobic functionality and a high adhesive force towards water. The origin of the high adhesive forces of gecko feet to water could be attributed to the high density nanopillars that contact the water. Inspired by this, polyimide films with gecko-like multiscale structures were constructed by using anodic aluminum oxide templates, exhibiting superhydrophobicity and a strong adhesive force towards water. The static water contact angle is larger than 150° and the adhesive force to water is about 66 μN. The resultant gecko-inspired polyimide film can be used as a ``mechanical hand'' to snatch micro-liter liquids. We expect this work will provide the inspiration to reveal the mechanism of the high-adhesive superhydrophobic of geckos and extend the practical applications of polyimide materials.

  16. Validation of a new radiographic protocol for Asian elephant feet and description of their radiographic anatomy.

    Science.gov (United States)

    Mumby, C; Bouts, T; Sambrook, L; Danika, S; Rees, E; Parry, A; Rendle, M; Masters, N; Weller, R

    2013-10-05

    Foot problems are extremely common in elephants and radiography is the only imaging method available but the radiographic anatomy has not been described in detail. The aims of this study were to develop a radiographic protocol for elephant feet using digital radiography, and to describe the normal radiographic anatomy of the Asian elephant front and hind foot. A total of fifteen cadaver foot specimens from captive Asian elephants were radiographed using a range of projections and exposures to determine the best radiographic technique. This was subsequently tested in live elephants in a free-contact setting. The normal radiographic anatomy of the Asian elephant front and hind foot was described with the use of three-dimensional models based on CT reconstructions. The projection angles that were found to be most useful were 65-70° for the front limb and 55-60° in the hind limb. The beam was centred 10-15 cm proximal to the cuticle in the front and 10-15 cm dorsal to the plantar edge of the sole in the hind foot depending on the size of the foot. The protocol developed can be used for larger-scale diagnostic investigations of captive elephant foot disorders, while the normal radiographic anatomy described can improve the diagnostic reliability of elephant feet radiography.

  17. Inflammatory response study of gellan gum impregnated duck's feet derived collagen sponges.

    Science.gov (United States)

    Song, Jeong Eun; Lee, Seon Eui; Cha, Se Rom; Jang, Na Keum; Tripathy, Nirmalya; Reis, Rui L; Khang, Gilson

    2016-10-01

    Tissue engineered biomaterials have biodegradable and biocompatible properties. In this study, we have fabricated sponges using duck's feet derived collagen (DC) and gellan gum (GG), and further studied its inflammatory responses. The as-prepared duck's feet DC/GG sponges showed the possibility of application as a tissue engineering material through in vitro and in vivo experiments. The physical and chemical properties of sponges were characterized by compression strength, porosity, and scanning electron microscopy, etc. In vitro cell viability were investigated using 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) assay. An inflammatory response was studied after seeding RAW264.7 cells on as-fabricated sponges using reverse transcriptase-polymerase chain reaction. In vivo studies were carried out by implanting in subcutaneous nude mouse followed by extraction, histological staining. Collectively, superior results were showed by DC/GG sponges than GG sponge in terms of physical property and cell proliferation and thus can be considered as a potential candidate for future tissue engineering applications.

  18. Does knee motion contribute to feet-in-place balance recovery?

    Science.gov (United States)

    Cheng, Kuangyou B

    2016-06-14

    Although knee motions have been observed at loss of balance, the ankle and hip strategies have remained the focus of past research. The present study aimed to investigate whether knee motions contribute to feet-in-place balance recovery. This was achieved by experimentally monitoring knee motions during recovery from forward falling, and by simulating balance recovery movements with and without knee joint as the main focus of the study. Twelve participants initially held a straight body configuration and were released from different forward leaning positions. Considerable knee motions were observed especially at greater leaning angles. Simulations were performed using 3-segment (feet, shanks+thighs, and head+arms+trunk) and 4-segment (with separate shanks and thighs segments) planar models. Movements were driven by joint torque generators depending on joint angle, angular velocity, and activation level. Optimal joint motions moved the mass center projection to be within the base of support without excessive joint motion. The 3-segment model (without knee motions) generated greater backward linear momentum and had better balance performance, which confirmed the advantage of having only ankle/hip strategies. Knee motions were accompanied with less body angular momentum and a lower body posture, which could be beneficial for posture control and reducing falling impact, respectively.

  19. Trajectory Correction and Locomotion Analysis of a Hexapod Walking Robot with Semi-Round Rigid Feet

    Directory of Open Access Journals (Sweden)

    Yaguang Zhu

    2016-08-01

    Full Text Available Aimed at solving the misplaced body trajectory problem caused by the rolling of semi-round rigid feet when a robot is walking, a legged kinematic trajectory correction methodology based on the Least Squares Support Vector Machine (LS-SVM is proposed. The concept of ideal foothold is put forward for the three-dimensional kinematic model modification of a robot leg, and the deviation value between the ideal foothold and real foothold is analyzed. The forward/inverse kinematic solutions between the ideal foothold and joint angular vectors are formulated and the problem of direct/inverse kinematic nonlinear mapping is solved by using the LS-SVM. Compared with the previous approximation method, this correction methodology has better accuracy and faster calculation speed with regards to inverse kinematics solutions. Experiments on a leg platform and a hexapod walking robot are conducted with multi-sensors for the analysis of foot tip trajectory, base joint vibration, contact force impact, direction deviation, and power consumption, respectively. The comparative analysis shows that the trajectory correction methodology can effectively correct the joint trajectory, thus eliminating the contact force influence of semi-round rigid feet, significantly improving the locomotion of the walking robot and reducing the total power consumption of the system.

  20. Cubature Formula and Interpolation on the Cubic Domain

    Institute of Scientific and Technical Information of China (English)

    Huiyuan Li; Jiachang Sun; Yuan Xu

    2009-01-01

    Several cubature formulas on the cubic domains are derived using the dis-crete Fourier analysis associated with lattice tiling, as developed in [10]. The main results consist of a new derivation of the Gaussian type cubature for the product Cheby-shev weight functions and associated interpolation polynomials on [-1,1]2, as well as new results on [-1,1]3. In particular, compact formulas for the fundamental interpo-lation polynomials are derived, based on n3/4 + (n2) nodes of a cubature formula on [-1,1]3.

  1. CLOSED SMOOTH SURFACE DEFINED FROM CUBIC TRIANGULAR SPLINES

    Institute of Scientific and Technical Information of China (English)

    Ren-zhong Feng; Ren-hong Wang

    2005-01-01

    In order to construct closed surfaces with continuous unit normal, we introduce a new spline space on an arbitrary closed mesh of three-sided faces. Our approach generalizes an idea of Goodman and is based on the concept of 'Geometric continuity' for piecewise polynomial parametrizations. The functions in the spline space restricted to the faces are cubic triangular polynomials. A basis of the spline space is constructed of positive functions which sum to 1. It is also shown that the space is suitable for interpolating data at the midpoints of the faces.

  2. Exotic Universal Solutions in Cubic Superstring Field Theory

    CERN Document Server

    Erler, Theodore

    2010-01-01

    We present a class of analytic solutions of cubic superstring field theory in the universal sector on a non-BPS D-brane. Computation of the action and gauge invariant overlap reveal that the solutions carry half the tension of a non-BPS D-brane. However, the solutions do not satisfy the reality condition. In fact, they display an intriguing topological structure: We find evidence that conjugation of the solutions is equivalent to a gauge transformation that cannot be continuously deformed to the identity.

  3. Research on the Cutting Performance of Cubic Boron Nitride Tools

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    There were only two kinds of superhard tool material at the past, i.e. diamond and cubic boron nitride (CBN). Manmade diamond and CBN are manufactured by the middle of 20th century. Various manufacturing methods and manmade superhard materials were developed later. They were widely used in different industry and science areas. Recently, a new kind of superhard tool material, C 3N 4 coating film, had been developed. American physical scientists, A. M. Liu and M. L. Cohen, designed a new kind of inorganic c...

  4. Self-trapping transition in nonlinear cubic lattices

    CERN Document Server

    Naether, Uta; Guzmán-Silva, Diego; Molina, Mario I; Vicencio, Rodrigo A

    2013-01-01

    We explore the fundamental question about the critical nonlinearity value needed to dynamically localize energy in discrete nonlinear cubic (Kerr) lattices. We focus on the effective frequency and participation ratio of the profile to determine the transition into localization, performing several numerical simulations in one-, two-, and three-dimensional lattices. A simple criterium is developed - for the case of an initially localized excitation - defining the transition region in parameter space ("dynamical tongue") from a delocalized to a localized profile. A general analytical estimate of the critical nonlinearity value for which this transition occurs is obtained.

  5. Cubic versus spherical magnetic nanoparticles: the role of surface anisotropy.

    Science.gov (United States)

    Salazar-Alvarez, G; Qin, J; Sepelák, V; Bergmann, I; Vasilakaki, M; Trohidou, K N; Ardisson, J D; Macedo, W A A; Mikhaylova, M; Muhammed, M; Baró, M D; Nogués, J

    2008-10-08

    The magnetic properties of maghemite (gamma-Fe2O3) cubic and spherical nanoparticles of similar sizes have been experimentally and theoretically studied. The blocking temperature, T(B), of the nanoparticles depends on their shape, with the spherical ones exhibiting larger T(B). Other low temperature properties such as saturation magnetization, coercivity, loop shift or spin canting are rather similar. The experimental effective anisotropy and the Monte Carlo simulations indicate that the different random surface anisotropy of the two morphologies combined with the low magnetocrystalline anisotropy of gamma-Fe2O3 is the origin of these effects.

  6. Configuration spaces of an embedding torus and cubical spaces

    OpenAIRE

    Jourdan, Jean-Philippe

    2006-01-01

    For a smooth manifold M obtained as an embedding torus, A U Cx[-1,1], we consider the ordered configuration space F_k(M) of k distinct points in M. We show that there is a homotopical cubical resolution of F_k(M) defined from the configuration spaces of A and C. From it, we deduce a universal method for the computation of the pure braid groups of a manifold. We illustrate the method in the case of the Mobius band.

  7. Ionic Conduction in Cubic Zirconias at Low Temperatures

    Institute of Scientific and Technical Information of China (English)

    Ying LI; Yunfa CHEN; Jianghong GONG

    2004-01-01

    The ac conductivities of Y2O3 or CaO-stabilized cubic zirconias were obtained from complex impedance measurements in the temperature range from 373 to 473 K. By analyzing the temperature-dependence of the resultant dc conductivities, it was shown that the activation energies for conduction are lower than those reported previously for the same materials at high temperatures. Comparing the activation energy data with the theoretically estimated values revealed that there may exist a certain, although very small, amount of free oxygen vacancies in the test samples at low temperatures and the conduction in the test samples is a result of the migration of these free oxygen vacancies.

  8. Cubic to tetragonal crystal lattice reconstruction during ordering or decomposition

    Energy Technology Data Exchange (ETDEWEB)

    Cheong, Byung-kl [Carnegie-Mellon Univ., Pittsburgh, PA (United States). Dept. of Materials Science and Engineering

    1992-09-01

    This thesis studied thermodynamic stability and morphology of product phases in diffusional phase transformations involving cubic-to-tetragonal crystal lattice reconstructions. Two different kinds of diffusional transformations were examined: L1{sub 0} ordering (fcc to fct lattice change) and decomposition of off-stoichiometric B2 ordering alloys accompanying bcc to fcc Bain transformation. In the first case, Fe-45 at.% Pd alloys were studied by TEM; in the second, the Bain strain relaxation during decomposition of hyper-eutectoid Cu-9.04 wt% Be alloy was studied. CuAu and InMg were also studied.

  9. On the {P2, P3}-Factor of Cubic Graphs

    Institute of Scientific and Technical Information of China (English)

    GOU Kui-xiang; SUN Liang

    2005-01-01

    Let G = ( V, E) be a finite simple graph and Pn denote the path of order n. A spanning subgraph F is called a {P2, P3}-factor of G if each component of F is isomorphic to P2 or P3. With the path-covering method, it is proved that any connected cubic graph with at least 5 vertices has a { P2, P3 }-factor F such that | P3 (F) |≥|P2 (F) |, where P2 (F) and P3 (F) denote the set of components of P2 and P3 in F,respectively.

  10. Inhomogeneous atomic Bose-Fermi mixtures in cubic lattices.

    Science.gov (United States)

    Cramer, M; Eisert, J; Illuminati, F

    2004-11-05

    We determine the ground state properties of inhomogeneous mixtures of bosons and fermions in cubic lattices and parabolic confining potentials. For finite hopping we determine the domain boundaries between Mott-insulator plateaux and hopping-dominated regions for lattices of arbitrary dimension within mean-field and perturbation theory. The results are compared with a new numerical method that is based on a Gutzwiller variational approach for the bosons and an exact treatment for the fermions. The findings can be applied as a guideline for future experiments with trapped atomic Bose-Fermi mixtures in optical lattices.

  11. Compressibility and thermal expansion of cubic silicon nitride

    DEFF Research Database (Denmark)

    Jiang, Jianzhong; Lindelov, H.; Gerward, Leif

    2002-01-01

    The compressibility and thermal expansion of the cubic silicon nitride (c-Si3N4) phase have been investigated by performing in situ x-ray powder-diffraction measurements using synchrotron radiation, complemented with computer simulations by means of first-principles calculations. The bulk...... compressibility of the c-Si3N4 phase originates from the average of both Si-N tetrahedral and octahedral compressibilities where the octahedral polyhedra are less compressible than the tetrahedral ones. The origin of the unit cell expansion is revealed to be due to the increase of the octahedral Si-N and N-N bond...

  12. Theoretical and Experimental Study of Time Reversal in Cubic Crystals

    Institute of Scientific and Technical Information of China (English)

    陆铭慧; 张碧星; 汪承灏

    2004-01-01

    The self-adaptive focusing of the time reversal in anisotropic media is studied theoretically and experimentally. It is conducted for the compressional wave field in the cubic crystal silicon. The experimental result is in agreement with our theoretical analysis. The focusing gain and the displacement distributions of the time reversal field are analysed in detail. It is shown that the waves from different elements of the transducer array arrive at the original place of the source simultaneously after the time reversal operation. The waveform distortions caused by the velocity anisotropy can automatically be compensated for after the time reversal processing.

  13. Rotary Ultrasonic Machining of Poly-Crystalline Cubic Boron Nitride

    Directory of Open Access Journals (Sweden)

    Kuruc Marcel

    2014-12-01

    Full Text Available Poly-crystalline cubic boron nitride (PCBN is one of the hardest material. Generally, so hard materials could not be machined by conventional machining methods. Therefore, for this purpose, advanced machining methods have been designed. Rotary ultrasonic machining (RUM is included among them. RUM is based on abrasive removing mechanism of ultrasonic vibrating diamond particles, which are bonded on active part of rotating tool. It is suitable especially for machining hard and brittle materials (such as glass and ceramics. This contribution investigates this advanced machining method during machining of PCBN.

  14. Cubic Plus Association Equation of State for Flow Assurance Projects

    DEFF Research Database (Denmark)

    dos Santos, Leticia Cotia; Abunahman, Samir Silva; Tavares, Frederico Wanderley

    2015-01-01

    Thermodynamic hydrate inhibitors such as methanol, ethanol, (mono) ethylene glycol (MEG), and triethylene glycol (TEG) are widely used in the oil and gas industry. On modeling these compounds, we show here how the CPA equation of state was implemented in an in-house process simulator as an in......-built model: To validate the implementation, we show calulations for binary systems containing hydrate inhibitors and water or hydrocarbons using the Cubic Plus Association (CPA) and Soave-Redlich-Kwong (SRK) equation of states, also comparing against experimental data. For streams containing natural gas...

  15. Elasticity tensor and ultrasonic velocities for anisotropic cubic polycrystal

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The orientation distribution of crystallites in a polycrystal can be described by the orientation distribution function(ODF) . The ODF can be expanded under the Wigner D-bases. The expanded coefficients in the ODF are called the texture coefficients. In this paper,we use the Clebsch-Gordan expression to derive an explicit expression of the elasticity tensor for an anisotropic cubic polycrystal. The elasticity tensor contains three material constants and nine texture coefficients. In order to measure the nine texture coefficients by ultrasonic wave,we give relations between the nine texture coefficients and ultrasonic propagation velocities. We also give a numerical example to check the relations.

  16. Tensor tomography of stresses in cubic single crystals

    Directory of Open Access Journals (Sweden)

    Dmitry D. Karov

    2015-03-01

    Full Text Available The possibility of optical tomography applying to investigation of a two-dimensional and a three-dimensional stressed state in single cubic crystals has been studied. Stresses are determined within the framework of the Maxwell piezo-optic law (linear dependence of the permittivity tensor on stresses and weak optical anisotropy. It is shown that a complete reconstruction of stresses in a sample is impossible both by translucence it in the parallel planes system and by using of the elasticity theory equations. For overcoming these difficulties, it is offered to use a method of magnetophotoelasticity.

  17. Antitumor Activities of Crude Extracts of Flavonoids from Flos LoniceraeConfusae on MCF-7 Cell%山银花黄酮粗提物对MCF-7细胞增殖及凋亡的作用

    Institute of Scientific and Technical Information of China (English)

    谢雁飞; 徐望龙; 刘刚; 姚旭; 周斌; 郭玉

    2015-01-01

    目的:体外观察山银花黄酮粗提物对MCF-7细胞增殖和凋亡的影响,为其黄酮类化合物的进一步开发利用提供理论依据。方法 MTT法检测山银花粗提物对MCF-7细胞增殖的抑制作用;Hoechst33342染色法观察MCF-7细胞凋亡;流式细胞术检测MCF-7细胞的凋亡率。结果高于200μg·mL-1的山银花粗提物对MCF-7细胞增殖有显著抑制作用(P<0.05)。山银花粗提物对细胞形态有明显影响,随浓度的增加,细胞核被染成亮蓝色的细胞比例明显增加。0μg·mL-1、100μg·mL-1、300μg·mL-1、600μg·mL-1的山银花粗提物作用的MCF-7细胞凋亡率分别为(3.89±0.70)%、(10.40±0.92)%、(22.02±1.22)%、(27.03±0.75)%。结论山银花黄酮粗提物对MCF-7肿瘤细胞有明显的抑制增殖与诱导凋亡作用,其效应与浓度呈正相关。%Objective To investigate the effects of flavoniods crude extract from Flos Lonicerae Confusae on the prolif-eration and apoptosis of MCF-7 cells, so as to provide the material foundation and scientific basis for further exploration and utilization. Methods The inhibition effects on proliferation of MCF-7 cells were tested by MTT. The morphological changes of MCF-7 apoptosis were observed by Hoechst 33342 staining. Flow cytometry was involved to measure the apoptosis rate of MCF-7 cells. Results The flavoniods crude extract of concentration more than 200μg·mL-1 had great inhibition effect on the proliferation of MCF-7 cells (P<0.05 vs. control). The crude extract also had a significant effect on cell morphology. The cell ratio of nucleus stained into light blue increased along with the increase of concentration of the extracts. The apoptosis rates of MCF-7 induced by a concentration of 100μg·mL-1, 300μg·mL-1 and 600μg·mL-1 were (10.4±0.92)%, (22.02 ±1.22)%and (27.03±0.75)%, respectively. Conclusion The crude flavonoids extracts from Flos Lonicerae Confusae had great inhibition on

  18. An increased fluid intake leads to feet swelling in 100-km ultra-marathoners - an observational field study

    Directory of Open Access Journals (Sweden)

    Cejka Caroline

    2012-04-01

    Full Text Available Abstract Background An association between fluid intake and changes in volumes of the upper and lower limb has been described in 100-km ultra-marathoners. The purpose of the present study was (i to investigate the association between fluid intake and a potential development of peripheral oedemas leading to an increase of the feet volume in 100-km ultra-marathoners and (ii to evaluate a possible association between the changes in plasma sodium concentration ([Na+] and changes in feet volume. Methods In seventy-six 100-km ultra-marathoners, body mass, plasma [Na+], haematocrit and urine specific gravity were determined pre- and post-race. Fluid intake and the changes of volume of the feet were measured where the changes of volume of the feet were estimated using plethysmography. Results Body mass decreased by 1.8 kg (2.4% (p +] increased by 1.2% (p p = 0.0005. The volume of the feet remained unchanged (p > 0.05. Plasma volume and urine specific gravity increased (p r = 0.54, p +] (r = -0.28, p = 0.0142. Running speed was negatively related to both fluid intake (r = -0.33, p = 0.0036 and the change in feet volume (r = -0.23, p = 0.0236. The change in the volume of the feet was negatively related to the change in plasma [Na+] (r = -0.26, p = 0.0227. The change in body mass was negatively related to both post-race plasma [Na+] (r = -0.28, p = 0.0129 and running speed (r = -0.34, p = 0.0028. Conclusions An increase in feet volume after a 100-km ultra-marathon was due to an increased fluid intake.

  19. Differential ability of antiestrogens to stimulate breast cancer cell (MCF-7) growth in vivo and in vitro.

    Science.gov (United States)

    Gottardis, M M; Wagner, R J; Borden, E C; Jordan, V C

    1989-09-01

    We have previously described an MCF-7 breast cancer cell variant, MCF-7TAM, which is stimulated to grow in athymic mice by tamoxifen (TAM) (M. M. Gottardis and V. C. Jordan, Cancer Res., 48:5183-5187, 1988). Earlier experiments have shown that TAM exhibits some profound estrogen-like effects in mice whereas TAM is less estrogenic in the rat. The aim in these studies was to compare the ability of MCF-7TAM to grow in different host environments and to determine whether the TAM-stimulated phenotype could be maintained in vitro. Ovariectomized athymic mice and rats were implanted with 1-mm3 pieces of MCF-7TAM tumor and treated with estradiol, TAM, or control silastic capsules. After 9 weeks of growth in either species, TAM or estradiol-treated groups both had sustained growth of MCF-7TAM compared with the control groups. To determine the effects of estradiol and TAM on immune function in athymic mice, splenocytes from treated or control athymic mice, challenged with poly(I:C), were assayed for natural killer (NK) cell activity against 51Cr-labeled YAC1 target cells. Both estradiol and TAM abolished lytic activity by 12 weeks of treatment. To evaluate the role of a decrease in NK-cell activity in the host on growth of MCF-7TAM xenografts we compared the growth effects in athymic and NK-cell deficient, ovariectomized beige mice. TAM stimulated MCF-7TAM in both beige and athymic mice; however, the tumor grew more rapidly in control beige mice than in control athymic mice. This study demonstrated that TAM-stimulated growth could occur in vivo. However, TAM or 4-hydroxytamoxifen did not cause a stimulation of MCF-7TAM compared with wild-type MCF-7 cells when experiments were conducted in vitro. These studies demonstrate that a suppression immune function can facilitate the growth of MCF-7TAM in athymic animals. However, additional components of the host environment contribute to TAM-stimulated growth in vivo.

  20. Cubic optical elements for an accommodative intraocular lens.

    Science.gov (United States)

    Simonov, Aleksey N; Vdovin, Gleb; Rombach, Michiel C

    2006-08-21

    We present a new accommodative intraocular lens based on a two-element varifocal Alvarez lens. The intraocular lens consists of (1) an anterior element combining a spherical lens for refractive power with a cubic surface for the varifocal effect, and (2) a posterior element with a cubic surface only. The focal length of the IOL lens changes when the superimposed refractive elements shift in opposite directions in a plane perpendicular to the optical axis. The ciliary muscle will drive the accommodation by a natural process of contraction and relaxation. Results of ray-tracing simulations of the model eye with the two-element intraocular lens are presented for on-axis and off-axis vision. The configuration of the lens is optimized to reduce refractive errors as well as effects of misalignment. A prototype with a clear aperture of ~5.7 mm is manufactured and evaluated in air with a Shack-Hartmann wave-front sensor. It provides an accommodation range of ~4 dioptres in the eye at a ~0.75-mm lateral displacement of the optical elements. The experimentally measured on-axis optical performance of the IOL lens agrees with the theoretically predicted performance.

  1. Nonlinear structure formation in the Cubic Galileon gravity model

    CERN Document Server

    Barreira, Alexandre; Hellwing, Wojciech A; Baugh, Carlton M; Pascoli, Silvia

    2013-01-01

    We model the linear and nonlinear growth of large scale structure in the Cubic Galileon gravity model, by running a suite of N-body cosmological simulations using the {\\tt ECOSMOG} code. Our simulations include the Vainshtein screening effect, which reconciles the Cubic Galileon model with local tests of gravity. In the linear regime, the amplitude of the matter power spectrum increases by $\\sim 25%$ with respect to the standard $\\Lambda$CDM model today. The modified expansion rate accounts for $\\sim 20%$ of this enhancement, while the fifth force is responsible for only $\\sim 5%$. This is because the effective unscreened gravitational strength deviates from standard gravity only at late times, even though it can be twice as large today. In the nonlinear regime ($k \\gtrsim 0.1 h\\rm{Mpc}^{-1}$), the fifth force leads to only a modest increase ($\\lesssim 8%$) in the clustering power on all scales due to the very efficient operation of the Vainshtein mechanism. Such a strong effect is typically not seen in other...

  2. A family of quasi-cubic blended splines and applications

    Institute of Scientific and Technical Information of China (English)

    SU Ben-yue; TAN Jie-qing

    2006-01-01

    A class of quasi-cubic B-spline base functions by trigonometric polynomials are established which inherit properties similar to those of cubic B-spline bases. The corresponding curves with a shape parameter α, defined by the introduced base functions, include the B-spline curves and can approximate the B-spline curves from both sides. The curves can be adjusted easily by using the shape parameter α, where dpi(α,t) is linear with respect to dα for the fixed t. With the shape parameter chosen properly,the defined curves can be used to precisely represent straight line segments, parabola segments, circular arcs and some transcendental curves, and the corresponding tensor product surfaces can also represent spherical surfaces, cylindrical surfaces and some transcendental surfaces exactly. By abandoning positive property, this paper proposes a new C2 continuous blended interpolation spline based on piecewise trigonometric polynomials associated with a sequence of local parameters. Illustration showed that the curves and surfaces constructed by the blended spline can be adjusted easily and freely. The blended interpolation spline curves can be shape-preserving with proper local parameters since these local parameters can be considered to be the magnification ratio to the length of tangent vectors at the interpolating points. The idea is extended to produce blended spline surfaces.

  3. Partially Blended Constrained Rational Cubic Trigonometric Fractal Interpolation Surfaces

    Science.gov (United States)

    Chand, A. K. B.; Tyada, K. R.

    2016-08-01

    Fractal interpolation is an advance technique for visualization of scientific shaped data. In this paper, we present a new family of partially blended rational cubic trigonometric fractal interpolation surfaces (RCTFISs) with a combination of blending functions and univariate rational trigonometric fractal interpolation functions (FIFs) along the grid lines of the interpolation domain. The developed FIFs use rational trigonometric functions pi,j(θ) qi,j(θ), where pi,j(θ) and qi,j(θ) are cubic trigonometric polynomials with four shape parameters. The convergence analysis of partially blended RCTFIS with the original surface data generating function is discussed. We derive sufficient data-dependent conditions on the scaling factors and shape parameters such that the fractal grid line functions lie above the grid lines of a plane Π, and consequently the proposed partially blended RCTFIS lies above the plane Π. Positivity preserving partially blended RCTFIS is a special case of the constrained partially blended RCTFIS. Numerical examples are provided to support the proposed theoretical results.

  4. Observation of Body-Centered Cubic Gold Nanocluster.

    Science.gov (United States)

    Liu, Chao; Li, Tao; Li, Gao; Nobusada, Katsuyuki; Zeng, Chenjie; Pang, Guangsheng; Rosi, Nathaniel L; Jin, Rongchao

    2015-08-17

    The structure of nanoparticles plays a critical role in dictating their material properties. Gold is well known to adopt face-centered cubic (fcc) structure. Herein we report the first observation of a body-centered cubic (bcc) gold nanocluster composed of 38 gold atoms protected by 20 adamantanethiolate ligands and two sulfido atoms ([Au38S2(SR)20], where R=C10H15) as revealed by single-crystal X-ray crystallography. This bcc structure is in striking contrast with the fcc structure of bulk gold and conventional Au nanoparticles, as well as the bi-icosahedral structure of [Au38(SCH2CH2Ph)24]. The bcc nanocluster has a distinct HOMO-LUMO gap of ca. 1.5 eV, much larger than the gap (0.9 eV) of the bi-icosahedral [Au38(SCH2CH2Ph)24]. The unique structure of the bcc gold nanocluster may be promising in catalytic applications.

  5. Four-dimensional black holes in Einsteinian cubic gravity

    Science.gov (United States)

    Bueno, Pablo; Cano, Pablo A.

    2016-12-01

    We construct static and spherically symmetric generalizations of the Schwarzschild- and Reissner-Nordström-(anti-)de Sitter [RN-(A)dS] black-hole solutions in four-dimensional Einsteinian cubic gravity (ECG). The solutions are characterized by a single function which satisfies a nonlinear second-order differential equation. Interestingly, we are able to compute independently the Hawking temperature T , the Wald entropy S and the Abbott-Deser mass M of the solutions analytically as functions of the horizon radius and the ECG coupling constant λ . Using these we show that the first law of black-hole mechanics is exactly satisfied. Some of the solutions have positive specific heat, which makes them thermodynamically stable, even in the uncharged and asymptotically flat case. Further, we claim that, up to cubic order in curvature, ECG is the most general four-dimensional theory of gravity which allows for nontrivial generalizations of Schwarzschild- and RN-(A)dS characterized by a single function which reduce to the usual Einstein gravity solutions when the corresponding higher-order couplings are set to zero.

  6. Novel Cubic Magnetite Nanoparticle Synthesis Using Room Temperature Ionic Liquid

    Directory of Open Access Journals (Sweden)

    M. Sundrarajan

    2012-01-01

    Full Text Available Room Temperature Ionic liquids are relatively more useful in the synthesis of inorganic nanostructured materials because of their unique properties. To synthesize the iron oxide nanoparticle in simple precipitation method, a novel ionic liquid was used as the greener medium and stabilizing agent namely “1-n-butyl-3-methylimidazolium trifluoromethane sulfonate [BMIM][TfO]”. The crystallinity, chemical structure, morphology and magnetic properties of the synthesized magnetite nanoparticles have been characterized by using X-ray diffraction (XRD, Fourier Transform Infrared (FT-IR, Scanning electron microscopy (SEM, Atomic force microscopy(AFM, Transmission electron microscopy (TEM and Vibrating sample magnetometer (VSM studies. The XRD study is divulge that the synthesized magnetite nanoparticles have inverse spinel face centered cubic structure. The FT-IR vibration peaks show the formation of Fe3O4 nanoparticles, where the vibration peak for Fe-O is deliberately presence at 584 cm-1. The average particle size of the synthesized nanoparticles is found to be 35 nm. Homogeneously dispersed cubic shape with superstructure is found through SEM, AFM and TEM examination studies. The synthesized iron oxide nanoparticles have a high saturation magnetization value of 25 emu/g, which is very much useful for biomedical applications.

  7. 40 CFR 201.24 - Procedures for measurement at a 30 meter (100 feet) distance of the noise from locomotive and...

    Science.gov (United States)

    2010-07-01

    ... meter (100 feet) distance of the noise from locomotive and rail car operations and locomotive load cell... Measurement Criteria § 201.24 Procedures for measurement at a 30 meter (100 feet) distance of the noise from... locomotives have passed a distance 152.4 meters (500 feet) or 10 rail cars beyond the point at...

  8. Flavokawain derivative FLS induced G2/M arrest and apoptosis on breast cancer MCF-7 cell line.

    Science.gov (United States)

    Ali, Norlaily Mohd; Akhtar, M Nadeem; Ky, Huynh; Lim, Kian Lam; Abu, Nadiah; Zareen, Seema; Ho, Wan Yong; Alan-Ong, Han Kiat; Tan, Sheau Wei; Alitheen, Noorjahan Banu; Ismail, Jamil Bin; Yeap, Swee Keong; Kamarul, Tunku

    2016-01-01

    Known as naturally occurring biologically active compounds, flavokawain A and B are the leading chalcones that possess anticancer properties. Another flavokawain derivative, (E)-1-(2'-Hydroxy-4',6'-dimethoxyphenyl)-3-(4-methylthio)phenyl)prop-2-ene-1-one (FLS) was characterized with (1)H-nuclear magnetic resonance, electron-impact mas spectrometry, infrared spectroscopy, and ultraviolet ((1)H NMR, EI-MS, IR, and UV) spectroscopic techniques. FLS cytotoxic efficacy against human cancer cells (MCF-7, MDA-MB-231, and MCF-10A) resulted in the reduction of IC50 values in a time- and dose-dependent mode with high specificity on MCF-7 (IC50 of 36 μM at 48 hours) against normal breast cell MCF-10A (no IC50 detected up to 180 μM at 72 hours). Light, scanning electron, and fluorescent microscopic analysis of MCF-7 cells treated with 36 μM of FLS displayed cell shrinkage, apoptotic body, and DNA fragmentation. Additionally, induction of G2/M cell arrest within 24 hours and apoptosis at subsequent time points was discovered via flow cytometry analysis. The roles of PLK-1, Wee-1, and phosphorylation of CDC-2 in G2/M arrest and proapoptotic factors (Bax, caspase 9, and p53) in promotion of apoptosis of FLS against MCF-7 cells were discovered using fluorometric, quantitative real-time polymerase chain reaction, and Western blot analysis. Interestingly, the presence of SCH3 (thiomethyl group) on ring B structure contributed to the selective cytotoxicity against MCF-7 cells compared to other chalcones, flavokawain A and B. Overall, our data suggest potential therapeutic value for flavokawain derivative FLS to be further developed as a new anticancer drug.

  9. Salinomycin efficiency assessment in non-tumor (HB4a) and tumor (MCF-7) human breast cells.

    Science.gov (United States)

    Niwa, Andressa Megumi; D Epiro, Gláucia Fernanda Rocha; Marques, Lilian Areal; Semprebon, Simone Cristine; Sartori, Daniele; Ribeiro, Lúcia Regina; Mantovani, Mário Sérgio

    2016-06-01

    The search for anticancer drugs has led researchers to study salinomycin, an ionophore antibiotic that selectively destroys cancer stem cells. In this study, salinomycin was assessed in two human cell lines, a breast adenocarcinoma (MCF-7) and a non-tumor breast cell line (HB4a), to verify its selective action against tumor cells. Real-time assessment of cell proliferation showed that HB4a cells are more resistant to salinomycin than MCF-7 tumor cell line, and these data were confirmed in a cytotoxicity assay. The half maximal inhibitory concentration (IC50) values show the increased sensitivity of MCF-7 cells to salinomycin. In the comet assay, only MCF-7 cells showed the induction of DNA damage. Flow cytometric analysis showed that cell death by apoptosis/necrosis was only induced in the MCF-7 cells. The increased expression of GADD45A and CDKN1A genes was observed in all cell lines. Decreased expression of CCNA2 and CCNB1 genes occurred only in tumor cells, suggesting G2/M cell cycle arrest. Consequently, cell death was activated in tumor cells through strong inhibition of the antiapoptotic genes BCL-2, BCL-XL, and BIRC5 genes in MCF-7 cells. These data demonstrate the selectivity of salinomycin in killing human mammary tumor cells. The cell death observed only in MCF-7 tumor cells was confirmed by gene expression analysis, where there was downregulation of antiapoptotic genes. These data contribute to clarifying the mechanism of action of salinomycin as a promising antitumor drug and, for the first time, we observed the higher resistance of HB4a non-tumor breast cells to salinomycin.

  10. 'Focus on feet'--the effects of systemic lupus erythematosus: a narrative review of the literature.

    Science.gov (United States)

    Williams, A E; Crofts, G; Teh, L S

    2013-09-01

    The manifestations of systemic lupus erythematosus (SLE) vary between individuals, from the severe and life-threatening renal and central nervous system involvement, to the involvement of skin, musculoskeletal and vascular system, and the complications of infection influencing the quality of life. However, as specific manifestations affecting the lower limb are perceived as receiving little focus, the purpose of this narrative literature review is to identify the specific factors associated with SLE that may have implications for lower limb and foot morbidity. A structured search of databases was conducted. The inclusion was restricted to publications in the English language, those that specifically investigate the feet as affected with SLE. No restriction on year of publication was imposed to reduce publication bias and to capture as many publication in relation to feet. Eleven papers fulfilled the inclusion criteria. There were seven additional papers that made observations related to the articular or vascular complications of the feet. This narrative review provides some information on how SLE affects the lower limb and foot in relation to the musculoskeletal and vascular systems. However, there is a lack of literature that specifically focuses on all the manifestations of SLE and the complications associated with its management. There are indications that SLE affects lower limb and foot morbidity but the scale of these problems is unclear and this is partly because of the absence of research and the lack of a 'gold standard' framework for the assessment of the lower limb and foot. In addition to clinical foot health assessment, ultrasonography may be a useful alternative to plain film radiography or magnetic resonance imaging (MRI) in capturing the extent of articular and extra-articular manifestations. Further, the Ankle Brachial Pressure Index (ABPI) may be useful in identifying those with atherosclerosis and ischaemia. There are indications that SLE affects

  11. 高胰岛素对MCF-7/ADR细胞化疗敏感性的影响%Effects of high insulin on chemotherapeutic sensitivity in MCF-7/ADR cells

    Institute of Scientific and Technical Information of China (English)

    朱楠楠; 穆兰; 李代清

    2016-01-01

    Objective To analyse the effects of high insulin on the expression and function of P-glycoprotein (P-gp), and preliminarily investigate the influence of insulin on chemotherapeutic sensitivity in MCF-7/ADR cells. Methods MCF-7/ADR cells were cultured with different concentrations of insulin(0.001, 0.005, 0.01, 0.05 and 0.1μmol/L). Real-time PCR was used to detect the expression of P-gp mRNA. Western blot assay was used to detect the expression level of P-gp. Rhodamine 123 was used to detect the efflux function level of P-gp. Cell viability and chemotherapeutic sensitivity were detected by MTT assay. Results High concentration of insulin (0.1 μmol/L) promoted the proliferation of MCF-7/ADR cells. The concentration of insulin (0.05 and 0.1 μmol/L) accelerated P-gp mRNA and protein expression, which also augmented the efflux function of P-glycoprotein and reduced the chemotherapeutic sensitivity to epirubicin. Conclusion High concentration of insulin may influence the drug resistance of breast cancer cells by promoting the expression and function of P-glycoprotein of MCF-7/ADR cells.%目的:分析高胰岛素对MCF-7/ADR细胞P-糖蛋白(P-gp)表达和功能的影响,并初步探讨胰岛素对MCF-7/ADR细胞化疗敏感性的影响。方法用不同胰岛素浓度(0.001、0.005、0.01、0.05、0.10μmol/L)的全细胞培养基干预MCF-7/ADR细胞,分别采用Real-time PCR法检测细胞中P-gp mRNA表达,Western Blot法检测细胞中P-gp蛋白表达水平,罗丹明123荧光实验测定P-gp的外排功能变化,MTT法检测MCF-7/ADR细胞活性及化疗敏感性。结果0.10μmol/L的胰岛素可促进MCF-7/ADR细胞增殖,0.05及0.10μmol/L浓度的胰岛素可增加MCF-7/ADR细胞P-gp mRNA及蛋白水平表达,并能增加P-gp的外排功能,降低MCF-7/ADR细胞对表阿霉素的化疗敏感性。结论高浓度胰岛素可能通过促进MCF-7/ADR细胞P-gp的表达和功能,增加乳腺癌细胞化疗耐药性,从而降低MCF-7

  12. The Effect of Over-expression of Pokemon gene onProliferation of MCF-7 Cells%Pokemon基因对MCF-7细胞增殖的影响

    Institute of Scientific and Technical Information of China (English)

    于玲玲; 张文光; 蒋宇扬; 徐威

    2011-01-01

    目的 转染Pokemon 表达载体到MCF-7 细胞中,探究Pokemon 对乳腺癌细胞增殖的影响.方法 构建Pokemon 基因表达质粒,瞬时转染Pokemon 表达质粒到乳腺癌细胞中,Western blot 检测pokemon 的蛋白水平表达情况,通过MTT 和平板克隆形成试验法观察Pokemon 对乳腺癌细胞增殖及克隆形成能力的影响.结果 MTT 法显示,随着培养时间的增加,MCF-7 细胞在转染Pokemon 后的生长速度明显增加;细胞平板克隆形成试验显示,MCF-7 细胞在转染Pokemon 后克隆数明显增加,由此可以说明Pokemon 能增强癌细胞MCF-7 克隆形成能力.结论 Pokemon 作为一个致癌基因,能促进乳腺癌MCF-7 细胞系的增殖并增加其克隆形成能力.

  13. Copper ferrite nanoparticle-induced cytotoxicity and oxidative stress in human breast cancer MCF-7 cells.

    Science.gov (United States)

    Ahamed, Maqusood; Akhtar, Mohd Javed; Alhadlaq, Hisham A; Alshamsan, Aws

    2016-06-01

    Copper ferrite (CuFe2O4) nanoparticles (NPs) are important magnetic materials currently under research due to their applicability in nanomedicine. However, information concerning the biological interaction of copper ferrite NPs is largely lacking. In this study, we investigated the cellular response of copper ferrite NPs in human breast cancer (MCF-7) cells. Copper ferrite NPs were prepared by co-precipitation technique with the thermal effect. Prepared NPs were characterized by X-ray diffraction (XRD), field emission transmission electron microscopy (FETEM) and dynamic light scattering (DLS). Characterization data showed that copper ferrite NPs were crystalline, spherical with smooth surfaces and average diameter of 15nm. Biochemical studies showed that copper ferrite NPs induce cell viability reduction and membrane damage in MCF-7 cells and degree of induction was dose- and time-dependent. High SubG1 cell population during cell cycle progression and MMP loss with a concomitant up-regulation of caspase-3 and caspase-9 genes suggested that copper ferrite NP-induced cell death through mitochondrial pathway. Copper ferrite NP was also found to induce oxidative stress in MCF-7 cells as indicated by reactive oxygen species (ROS) generation and glutathione depletion. Cytotoxicity due to copper ferrite NPs exposure was effectively abrogated by N-acetyl-cysteine (ROS scavenger) suggesting that oxidative stress could be the plausible mechanism of copper ferrite NPs toxicity. Further studies are underway to explore the toxicity mechanisms of copper ferrite NPs in different types of human cells. This study warrants further generation of extensive biointeraction data before their application in nanomedicine.

  14. Insulin like growth factor 2 regulation of aryl hydrocarbon receptor in MCF-7 breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Tomblin, Justin K.; Salisbury, Travis B., E-mail: salisburyt@marshall.edu

    2014-01-17

    Highlights: •IGF-2 stimulates concurrent increases in AHR and CCND1 expression. •IGF-2 promotes the binding of AHR to the endogenous cyclin D1 promoter. •AHR knockdown inhibits IGF-2 stimulated increases in CCND1 mRNA and protein. •AHR knockdown inhibits IGF-2 stimulated increases in MCF-7 proliferation. -- Abstract: Insulin like growth factor (IGF)-1 and IGF-2 stimulate normal growth, development and breast cancer cell proliferation. Cyclin D1 (CCND1) promotes cell cycle by inhibiting retinoblastoma protein (RB1). The aryl hydrocarbon receptor (AHR) is a major xenobiotic receptor that also regulates cell cycle. The purpose of this study was to investigate whether IGF-2 promotes MCF-7 breast cancer proliferation by inducing AHR. Western blot and quantitative real time PCR (Q-PCR) analysis revealed that IGF-2 induced an approximately 2-fold increase (P < .001) in the expression of AHR and CCND1. Chromatin immunoprecipitation (ChIP), followed by Q-PCR indicated that IGF-2 promoted (P < .001) a 7-fold increase in AHR binding on the CCND1 promoter. AHR knockdown significantly (P < .001) inhibited IGF-2 stimulated increases in CCND1 mRNA and protein. AHR knockdown cells were less (P < .001) responsive to the proliferative effects of IGF-2 than control cells. Collectively, our findings have revealed a new regulatory mechanism by which IGF-2 induction of AHR promotes the expression of CCND1 and the proliferation of MCF-7 cells. This previously uncharacterized pathway could be important for the proliferation of IGF responsive cancer cells that also express AHR.

  15. Dracorhodin Perchlorate Induced Human Breast Cancer MCF-7 Apoptosis through Mitochondrial Pathways

    Science.gov (United States)

    Yu, Jing-hua; Zheng, Gui-bin; Liu, Chun-yu; Zhang, Li-ying; Gao, Hong-mei; Zhang, Ya-hong; Dai, Chun-yan; Huang, Lin; Meng, Xian-ying; Zhang, Wen-yan; Yu, Xiao-fang

    2013-01-01

    Objective: Dracorhodin perchlorate (DP) was a synthetic analogue of the antimicrobial anthocyanin red pigment dracorhodin. It was reported that DP could induce apoptosis in human prostate cancer, human gastric tumor cells and human melanoma, but the cytotoxic effect of DP on human breast cancer was not investigated. This study would investigate whether DP was a candidate chemical of anti-human breast cancer. Methods: The MTT assay reflected the number of viable cells through measuring the activity of cellular enzymes. Phase contrast microscopy visualized cell morphology. Fluorescence microscopy detected nuclear fragmentation after Hoechst 33258 staining. Flowcytometric analysis of Annexin V-PI staining and Rodamine 123 staining was used to detect cell apoptosis and mitochondrial membrane potential (MMP). Real time PCR detected mRNA level. Western blot examined protein expression. Results: DP dose and time-dependently inhibited the growth of MCF-7 cells. DP inhibited MCF-7 cell growth through apoptosis. DP regulated the expression of Bcl-2 and Bax, which were mitochondrial pathway proteins, to decrease MMP, and DP promoted the transcription of Bax and inhibited Bcl-2. Apoptosis-inducing factor (AIF) and cytochrome c which localized in mitochondrial in physiological condition were released into cytoplasm when MMP was decreased. DP activated caspase-9, which was the downstream of mitochondrial pathway. Therefore DP decreased MMP to release AIF and cytochrome c into cytoplasm, further activating caspase 9, lastly led to apoptosis. Conclusion: Therefore DP was a candidate for anti-breast cancer, DP induced apoptosis of MCF-7 through mitochondrial pathway. PMID:23869191

  16. Effect of prolonged hydroxytamoxifen treatment of MCF-7 cells on mitogen activated kinase cascade.

    Science.gov (United States)

    Rabenoelina, Fanjaniriana; Semlali, Abdelhabib; Duchesne, Marie-Josèphe; Freiss, Gilles; Pons, Michel; Badia, Eric

    2002-04-10

    Resistance to the antiestrogen tamoxifen is the main stumbling block for the success of breast cancer therapy. We focused our study on cellular alterations induced by a prolonged treatment with the active tamoxifen metabolite hydroxytamoxifen (OHT). We show that a prolonged OHT treatment (for up to 7 days) led to a progressive increase in the level of phosphorylated p44/42 mitogen activated kinase (MAP kinase) induced by 10(-7) M TPA stimulation, without any significant change in the protein level. This effect was also observed in MCF-7 cells grown first in medium containing dextran-coated charcoal-treated FCS (DCC medium) for 20 days prior to OHT treatment, indicating a specific effect of the antiestrogen and not an effect of estrogen deprivation. It was prevented by cotreatment with estradiol and not observed in the estrogen receptor negative HeLa cell line, suggesting that it was mediated by the estrogen receptor. TPA induced phosphorylation of MEK1/2 was also raised by OHT treatment, without any change in their protein level or Raf-1 and H-Ras levels. When the MCF-7R OHT resistant cell line was grown in antiestrogen containing medium, the level of phosphorylated p44/42 MAP kinase was also high but reversed when the antiestrogen was removed. The 2 other MAP kinase, JNK and P38 pathways were not affected in the same way by OHT treatment. In conclusion, our data reveal that a prolonged OHT treatment, by increasing p44/42 MAPK activity, affects a key step in the growth control of MCF-7 cells, although not sufficiently to overcome the growth inhibitory effect of the drug. Copyright 2002 Wiley-Liss, Inc.

  17. Trefoil factor-2, human spasmolytic polypeptide, promotes branching morphogenesis in MCF-7 cells.

    Science.gov (United States)

    Lalani, E N; Williams, R; Jayaram, Y; Gilbert, C; Chaudhary, K S; Siu, L S; Koumarianou, A; Playford, R; Stamp, G W

    1999-05-01

    Members of the trefoil factor (TFF) family are highly expressed in endodermal ulcerative wound healing and selectively in neoplastic proliferation of various glandular epithelia. There is some evidence that TFF1 and TFF3 affect cell motility, are indirectly involved in growth suppression, and are associated with mucin expression. TFF2 is co-expressed with TFF1 in gastric surface epithelial cells, but its potential role in vivo is unclear. We analyzed potential effects on cell proliferation and morphogenesis of TFF2 on a panel of epithelial and mesenchymal cell lines. TFF2 had no measurable effect on the proliferation of any of the cell lines tested. In type 1 collagen lattices, TFF2 at a low concentration (25-100 nM) induced the formation of highly complex branched structures in the breast carcinoma cell line MCF-7 over a period of 14 to 42 days. No significant effect was shown with other cell lines. This morphogenic effect was abolished by monoclonal antibodies specific for either TFF2 or TFF1. TFF2 did not affect cell motility in MCF-7 cells as measured by videomicroscopy, in contrast to previous studies using TFF1. TFF2-treated MCF-7 colonies showed a 30% reduction in the number of apoptotic bodies, corroborated by trypan blue exclusion and DNA fragmentation ELISA, indicating TFF2 promotes cell survival via inhibition of apoptosis and can act as a morphogen in the presence of TFF1. These properties may complement the actions of TFF1 as a motogen and may explain differential expression in endodermal wound healing.

  18. Phenotypic and Molecular Characterization of MCF10DCIS and SUM Breast Cancer Cell Lines

    Directory of Open Access Journals (Sweden)

    Nandita Barnabas

    2013-01-01

    Full Text Available We reviewed the phenotypic and molecular characteristics of MCF10DCIS.com and the SUM cell lines based on numerous studies performed over the years. The major signaling pathways that give rise to the phenotype of these cells may serve as a good resource of information when researchers in drug discovery and development use these cells to identify novel targets and biomarkers. Major signaling pathways and mutations affecting the coding sequence are also described providing important information when using these cells as a model in a variety of studies.

  19. Activation of bone morphogenetic protein-6 gene transcription in MCF-7 cells by estrogen

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ming; YAN Ji-dong; HANG Lei; WANG Qing; L(U) Shu-jun; ZHANG Jie; ZHU Tian-hui

    2005-01-01

    Background Bone morphogenetic protein-6 (BMP-6) is closely correlated with tumor differentiation and skeletal metastasis. Estrogen is considered as a stimulant for the initiation and promotion of breast cancer. Previous studies demonstrated that 17β-estadiol (E2) can selectively increase the expression of BMP-6. This experiment is designed to detect the molecular mechanism of estrogen activating BMP-6 gene transcription in human estrogen receptor positive (ER+) breast cancer cell line MCF-7. Methods After the treatment of MCF-7 cells with E2 at different concentrations (10-11 mol/L, 10-9 mol/L, 10-7 mol/L), the BMP-6 expression level was examined through real-time polymerase chain reaction. Through restriction enzyme digestion, human BMP-6 1.2 kb long promoter, BMP-6 0.7 kb long promoter was cloned into pGL-3 basic vector; after the treatment with 10-7 mol/L E2, luciferase activities of the two promoters were detected. Site-directed mutagenesis was performed to obtain the mutant forms of estrogen response element half-site (1/2 ERE) element and Sp1 sites in the BMP-6 promoter, the activities of these mutant form promoters were detected following the methods mentioned above. Chromatin immunoprecipitation (ChIP) assay was also used to confirm the binding of estrogen receptor α (Erα) on BMP-6 promoter in the presence of E2. Results E2 dose dependently increased BMP-6 mRNA expression in human ER+ breast cancer cell line MCF-7. At a dose of 10-7 mol/L E2, human BMP-6 1.2 kb promoter activity was increased by 90% compared with the control group treated with ethanol (P<0.05). Both the 1/2 ERE response element mutant form and the Sp1 site mutant form of the BMP-6 promoter abolished the activation of the BMP-6 promoter's response to E2. Through ChIP assay, the binding of Erα on 1/2 ERE response element in BMP-6 promoter was further validated. Conclusion Estrogen induces BMP-6 expression in human ER+ breast cancer cell line MCF-7 through its receptor Erα binding on 1

  20. Design and construction of Thermoelectric Footwear Heating System for illness feet.

    Science.gov (United States)

    Işik, Hakan

    2005-12-01

    In this study, a Thermoelectric Footwear Heating System is developed to use in cold weather conditions. The temperature is controlled by an analog electronic control system. Thermoelectric module is used to heat the bottom of the foot. A negative temperature coefficient (NTC) temperature sensor is used to sense the temperature and the temperature is controlled by an electronic circuit proportionally. A 3.5 V, 5000 mAh rechargeable battery is used as the power source. The temperature range of the system is between +15 degrees C and +50 degrees C. Developed footwear heating system is tested against various temperature conditions, and offer better results in the case of heating the illness feet.

  1. Results of Ponseti Brasil Program: Multicentric Study in 1621 Feet: Preliminary Results.

    Science.gov (United States)

    Nogueira, Monica P; Queiroz, Ana C D B F; Melanda, Alessandro G; Tedesco, Ana P; Brandão, Antonio L G; Beling, Claudio; Violante, Francisco H; Brandão, Gilberto F; Ferreira, Laura F A; Brambila, Leandro S; Leite, Leopoldina M; Zabeu, Jose L; Kim, Jung H; Fernandes, Kalyana E; Arima, Marcia A S; Aguilar, Maria D P Q; Farias Filho, Orlando C D; Oliveira Filho, Oscar B D A; Pinho, Solange D S; Moulin, Paulo; Volpi, Reinaldo; Fox, Mark; Greenwald, Miles F; Lyle, Brandon; Morcuende, Jose A

    The Ponseti method has been shown to be the most effective treatment for congenital clubfoot. The current challenge is to establish sustainable national clubfoot treatment programs that utilize the Ponseti method and integrate it within a nation's governmental health system. The Brazilian Ponseti Program (Programa Ponseti Brasil) has increased awareness of the utility of the Ponseti method and has trained >500 Brazilian orthopaedic surgeons in it. A group of 18 of those surgeons had been able to reproduce the Ponseti clubfoot treatment, and compiled their initial results through structured spreadsheet. The study compiled 1040 patients for a total of 1621 feet. The average follow-up time was 2.3 years with an average correction time of approximately 3 months. Patients required an average of 6.40 casts to achieve correction. This study demonstrates that good initial correction rates are reproducible after training; from 1040 patients only 1.4% required a posteromedial release. Level IV.

  2. Vertical illusory self-motion through haptic stimulation of the feet

    DEFF Research Database (Denmark)

    Nordahl, Rolf; Nilsson, Niels Christian; Turchet, Luca

    2012-01-01

    Circular and linear self-motion illusions induced through visual and auditory stimuli have been studied rather extensively. While the ability of haptic stimuli to augment such illusions has been investigated, the self-motion illusions which primarily are induced by stimulation of the haptic...... modality remain relatively unexplored. In this paper, we present an experiment performed with the intention of investigating whether it is possible to use haptic stimulation of the main supporting areas of the feet to induce vertical illusory self-motion on behalf of unrestrained participants during...... to generate the haptic feedback while the final condition included no haptic feedback. Analysis of self-reports were used to assess the participants' experience of illusory self-motion. The results indicate that such illusions are indeed possible. Significant differences were found between the condition...

  3. SPECTRO-POLARIMETRIC IMAGING REVEALS HELICAL MAGNETIC FIELDS IN SOLAR PROMINENCE FEET

    Energy Technology Data Exchange (ETDEWEB)

    González, M. J. Martínez; Sainz, R. Manso; Ramos, A. Asensio; Beck, C.; Díaz, A. J. [Instituto de Astrofísica de Canarias, Vía Láctea s/n, E-38205 La Laguna, Tenerife (Spain); Rodríguez, J. de la Cruz [Institute for Solar Physics, Department of Astronomy, Stockholm University, Albanova University Center, SE-10691 Stockholm (Sweden)

    2015-03-20

    Solar prominences are clouds of cool plasma levitating above the solar surface and insulated from the million-degree corona by magnetic fields. They form in regions of complex magnetic topology, characterized by non-potential fields, which can evolve abruptly, disintegrating the prominence and ejecting magnetized material into the heliosphere. However, their physics is not yet fully understood because mapping such complex magnetic configurations and their evolution is extremely challenging, and must often be guessed by proxy from photometric observations. Using state-of-the-art spectro-polarimetric data, we reconstruct the structure of the magnetic field in a prominence. We find that prominence feet harbor helical magnetic fields connecting the prominence to the solar surface below.

  4. Healing of ulcers on the feet correlated with distal blood pressure measurements in occlusive arterial disease

    DEFF Research Database (Denmark)

    Holstein, P; Lassen, N A

    1980-01-01

    The frequency of healing in subchronic ulcers in 66 feet in 62 patients with arterial occlusive disease was correlated with the systolic digital blood pressure (SDBP) and the systolic ankle blood pressure (SABP), both measured with a strain gauge, and with the skin perfusion pressure on the heel...... of healing correlated significantly with the three distal blood pressure parameters investigated, the closest correlation being with the SDBP measured at the final examination, i.e. just after healing of the ulcer or just before an inevitable major amputation. Of the 22 cases with SDBP below 20 mmHg only two...... and peripheral neuropathy were frequent in the diabetic group. The data show that the systolic digital blood pressure is a particularly valuable prognostic parameter....

  5. Three cases of feet and hand amputation from Medieval Estremoz, Portugal.

    Science.gov (United States)

    Fernandes, Teresa; Liberato, Marco; Marques, Carina; Cunha, Eugénia

    2017-09-01

    Peri-mortem limb amputations are rarely reported in the paleopathological literature. The cases reported here concern severing of both hands and feet observed in three adult male skeletons, exhumed from the medieval Portuguese necropolis of Rossio do Marquês de Pombal, Estremoz, Portugal. The fact that they were found in the same site, in graves placed side by side, that all are young males, and that the three skeletons show similar perimortem injuries, make this a unique case meriting detailed analysis. Considering the lesions' location and pattern, as well as historical data, we hypothesize that this is a case of amputation as a consequence of judicial punishment. Estremoz was an important city in sustaining the Royal power at a regional scale during the medieval period. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Key parameters governing the densification of cubic-Li7La3Zr2O12 Li+ conductors

    Science.gov (United States)

    Yi, Eongyu; Wang, Weimin; Kieffer, John; Laine, Richard M.

    2017-06-01

    Cubic-Li7La3Zr2O12 (LLZO) is regarded as one of the most promising solid electrolytes for the construction of inherently safe, next generation all-solid-state Li batteries. Unfortunately, sintering these materials to full density with controlled grain sizes, mechanical and electrochemical properties relies on energy and equipment intensive processes. In this work, we elucidate key parameters dictating LLZO densification by tracing the compositional and structural changes during processing calcined and ball-milled Al3+ doped LLZO powders. We find that the powders undergo ion (Li+/H+) exchange during room temperature processing, such that on heating, the protonated LLZO lattice collapses and crystallizes to its constituent oxides, leading to reaction driven densification at sizes and protonation cannot be decoupled, and actually aid densification. We conclude that using fully decomposed nanoparticle mixtures, as obtained by liquid-feed flame spray pyrolysis, provides an ideal approach to use high surface and reaction energy to drive densification, resulting in pressureless sintering of Ga3+ doped LLZO thin films (25 μm) at 1130 °C/0.3 h to ideal microstructures (95 ± 1% density, 1.2 ± 0.2 μm average grain size) normally accessible only by pressure-assisted sintering. Such films offer both high ionic conductivity (1.3 ± 0.1 mS cm-1) and record low ionic area specific resistance (2 Ω cm2).

  7. Are old running shoes detrimental to your feet? A pedobarographic study

    Directory of Open Access Journals (Sweden)

    Makwana Nilesh

    2011-08-01

    Full Text Available Abstract Background Footwear characteristics have been implicated in fatigue and foot pain. The recommended time for changing running shoes is every 500 miles. The aim of our study was to assess and compare plantar peak pressures and pressure time integrals in new and old running shoes. Findings This was a prospective study involving 11 healthy female volunteers with no previous foot and ankle problems. New running shoes were provided to the participants. Plantar pressures were measured using the Novel Pedar system while walking with new and participants' personal old running shoes. Plantar pressures were measured in nine areas of the feet. Demographic data, age of old running shoes, Body Mass Index (BMI, peak pressures and pressure-time integral were acquired. The right and left feet were selected at random and assessed separately. Statistical analysis was done using the paired t test to compare measurements between old and new running shoes. The mean peak pressures were higher in new running shoes (330.5 ± 79.6 kiloPascals kPa when compared to used old running shoes (304 ± 58.1 kPa (p = 0.01. The pressure-time integral was significantly higher in the new running shoes (110 ± 28.3 kPa s compared to used old running shoes (100.7 ± 24.0 kPa s (p = 0.01. Conclusion Plantar pressure measurements in general were higher in new running shoes. This could be due to the lack of flexibility in new running shoes. The risk of injury to the foot and ankle would appear to be higher if running shoes are changed frequently. We recommend breaking into new running shoes slowly using them for mild physical activity.

  8. Antiwrinkle effect of topical adhesive pads on crow's feet: How long does the effect last for?

    Science.gov (United States)

    Mazzarello, Vittorio; Ferrari, Marco; Bulla, Antonio; Piu, Gabriella; Montella, Andrea

    2017-08-28

    Adhesive pads should reduce the action of the local muscle contraction on the skin leading to a decrease in the depth of existing wrinkles and the formation of new dynamic wrinkles. This study aims at assessing the antiwrinkles action of adhesive pads during time, and the temporary improvement of facial skin appearance by reducing the vision of linear wrinkles and improving skin elasticity. Thirty-nine subjects participated to a placebo-controlled study. In the short-term test, the measurements were taken 15, 30, and 60 minutes following 30 minutes application of the product; in the long-term test, the measurements were taken after wearing pads every night for 4 weeks. The roughness parameter of the skin surface was calculated by using a profilometry software 3D MEX(®) . In the short- and long-term tests, analyzing the average of the elastomeric measurements, no significant change was observed in any of the parameters analyzed after 15, 30, and 60 minutes. The adhesive pad decreased significantly all roughness skin parameters 15 minutes after short-term application and until 60 minutes after long-term application. These changes did not occur in the contralateral untreated zone. The use of topical adhesive pads improves wrinkles in the crow's feet area in the first hour after use. However, patient self-evaluation indicated that the use of topical adhesive pads for 3 weeks may offer subjective improvement in crow's feet zone over a 2 hour period. Topical adhesive pads are safe to use and tolerable for most users. © 2017 Wiley Periodicals, Inc.

  9. The initial ultrasonographic examination of hands and feet joints in patients with early rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    Monika Ponikowska

    2015-09-01

    Full Text Available Objectives : The aim was to assess of the morphology, intensity, and activity of changes in the first ultrasonographic (US examination of hands and feet in patients with early arthritis (lasting up to 12 months who were ultimately diagnosed with rheumatoid arthritis (RA. An attempt was made to demonstrate a correlation between the intensity of lesions in US and selected laboratory parameters. Material and methods : Ultrasonographic examination was performed using a LOGIC GE 500 device on a group of 60 patients with arthritis (46 women, 14 men aged 18–80, previously untreated. In total, 3120 hand and feet joints were examined. The assessment focused on the presence of joint effusion, synovial proliferation and power Doppler signals (assessed on a semi-quantitative scale. Each patient underwent laboratory tests, necessary for making a diagnosis. In order to analyze the correlations between changes in US and laboratory parameters, erythrocyte sedimentation rate (ESR, reactive protein test (CRP, rheumatoid factor (RF, and anti-citrullinated protein antibodies (ACPAs were used. Results : In the study group, the average duration of arthritis symptoms until the first US examination was 5.6 months. Among the 3120 examined hand and foot joints, deviations from the norm appeared in 1093 joints, synovial hypertrophy was found in 471 joints (grade 1 synovial hypertrophy was reported most frequently, while presence of signal in Power Doppler was revealed in 261 joints (grade 1 was observed most frequently. A statistically significant correlation was found between the intensity of changes in Power Doppler and CRP concentration. Conclusions : In patients with increased concentrations of CRP, we may expect arthritis of higher intensity, therefore, in order to prevent the progression of destructive changes, it is necessary to quickly implement effective disease-modifying antirheumatic treatment. The conducted research showed that the activity of joint

  10. Energy storage and release of prosthetic feet. Part 1: Biomechanical analysis related to user benefits.

    Science.gov (United States)

    Postema, K; Hermens, H J; de Vries, J; Koopman, H F; Eisma, W H

    1997-04-01

    The energy storing and releasing behaviour of 2 energy storing feet (ESF) and 2 conventional prosthetic feet (CF) were compared (ESF: Otto Bock Dynamic Pro and Hanger Quantum; CF: Otto Bock Multi Axial and Otto Bock Lager). Ten trans-tibial amputees were selected. The study was designed as a double-blind, randomised trial. For gait analysis a VICON motion analysis system was used with 2 AMTI force platforms. A special measuring device was used for measuring energy storage and release of the foot during a simulated step. The impulses of the anteroposterior component of the ground force showed small, statistically non-significant differences (deceleration phase: 22.7-23.4 Ns; acceleration phase: 17.0-18.4 Ns). The power storage and release phases as well as the net results also showed small differences (maximum difference in net result is 0.03 J kg-1). It was estimated that these differences lead to a maximum saving of 3% of metabolic energy during walking. It was considered unlikely that the subjects would notice this difference. It was concluded that during walking differences in mechanical energy expenditure of this magnitude are probably not of clinical relevance. Ankle power, as an indicator for energy storage and release gave different results to the energy storage and release as measured with the special test device, especially during landing response. In the biomechanical model (based on inverse dynamics) used in the gait analysis the deformation of the material is not taken into consideration and hence this method of gait analysis is probably not suitable for calculation of shock absorption.

  11. Exogenous and Endogeneous Disialosyl Ganglioside GD1b Induces Apoptosis of MCF-7 Human Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Sun-Hyung Ha

    2016-04-01

    Full Text Available Gangliosides have been known to play a role in the regulation of apoptosis in cancer cells. This study has employed disialyl-ganglioside GD1b to apoptosis in human breast cancer MCF-7 cells using exogenous treatment of the cells with GD1b and endogenous expression of GD1b in MCF-7 cells. First, apoptosis in MCF-7 cells was observed after treatment of GD1b. Treatment of MCF-7 cells with GD1b reduced cell growth rates in a dose and time dependent manner during GD1b treatment, as determined by XTT assay. Among the various gangliosides, GD1b specifically induced apoptosis of the MCF-7 cells. Flow cytometry and immunofluorescence assays showed that GD1b specifically induces apoptosis in the MCF-7 cells with Annexin V binding for apoptotic actions in early stage and propidium iodide (PI staining the nucleus of the MCF-7 cells. Treatment of MCF-7 cells with GD1b activated apoptotic molecules such as processed forms of caspase-8, -7 and PARP (Poly(ADP-ribose polymerase, without any change in the expression of mitochondria-mediated apoptosis molecules such as Bax and Bcl-2. Second, to investigate the effect of endogenously produced GD1b on the regulation of cell function, UDP-gal: β1,3-galactosyltransferase-2 (GD1b synthase, Gal-T2 gene has been transfected into the MCF-7 cells. Using the GD1b synthase-transfectants, apoptosis-related signal proteins linked to phenotype changes were examined. Similar to the exogenous GD1b treatment, the cell growth of the GD1b synthase gene-transfectants was significantly suppressed compared with the vector-transfectant cell lines and transfection activated the apoptotic molecules such as processed forms of caspase-8, -7 and PARP, but not the levels of expression of Bax and Bcl-2. GD1b-induced apoptosis was blocked by caspase inhibitor, Z-VAD. Therefore, taken together, it was concluded that GD1b could play an important role in the regulation of breast cancer apoptosis.

  12. Non-spherical micelles in an oil-in-water cubic phase

    DEFF Research Database (Denmark)

    Leaver, M.; Rajagopalan, V.; Ulf, O.

    2000-01-01

    The cubic phase formed between the microemulsion and hexagonal phases of the ternary pentaethylene glycol dodecyl ether (C12E5)-decane-water system and that doped with small amounts of sodium dodecylsulfate (SDS) have been investigated. The presence of discrete oil-swollen micelles in the cubic...... phase, both with and without SDS, was established by NMR self-diffusion. In addition H-2 NMR relaxation experiments have demonstrated that the micelles in the cubic phase are non-spherical, having grown and changed shape upon formation of the cubic phase from the micellar solution. Small angle...... scattering experiments indicate that the lattice parameter for the cubic phase is inconsistent with a simple packing of micelles. Whilst insufficient reflections were observed to establish the space group of the cubic phase uniquely, those that were are consistent with two commonly observed space groups...

  13. Xanthohumol, a Prenylated Chalcone from Hops, Inhibits the Viability and Stemness of Doxorubicin-Resistant MCF-7/ADR Cells

    Directory of Open Access Journals (Sweden)

    Ming Liu

    2016-12-01

    Full Text Available Xanthohumol is a unique prenylated flavonoid in hops (Humulus lupulus L. and beer. Xanthohumol has been shown to possess a variety of pharmacological activities. There is little research on its effect on doxorubicin-resistant breast cancer cells (MCF-7/ADR and the cancer stem-like cells exiting in this cell line. In the present study, we investigate the effect of xanthohumol on the viability and stemness of MCF-7/ADR cells. Xanthohumol inhibits viability, induces apoptosis, and arrests the cell cycle of MCF-7/ADR cells in a dose-dependent manner; in addition, xanthohumol sensitizes the inhibition effect of doxorubicin on MCF-7/ADR cells. Interestingly, we also find that xanthohumol can reduce the stemness of MCF-7/ADR cells evidenced by the xanthohumol-induced decrease in the colony formation, the migration, the percentage of side population cells, the sphere formation, and the down-regulation of stemness-related biomarkers. These results demonstrate that xanthohumol is a promising compound targeting the doxorubicin resistant breast cancer cells and regulating their stemness, which, therefore, will be applied as a potential candidate for the development of a doxorubicin-resistant breast cancer agent and combination therapy of breast cancer.

  14. Xanthohumol, a Prenylated Chalcone from Hops, Inhibits the Viability and Stemness of Doxorubicin-Resistant MCF-7/ADR Cells.

    Science.gov (United States)

    Liu, Ming; Yin, Hua; Qian, Xiaokun; Dong, Jianjun; Qian, Zhonghua; Miao, Jinlai

    2016-12-28

    Xanthohumol is a unique prenylated flavonoid in hops (Humulus lupulus L.) and beer. Xanthohumol has been shown to possess a variety of pharmacological activities. There is little research on its effect on doxorubicin-resistant breast cancer cells (MCF-7/ADR) and the cancer stem-like cells exiting in this cell line. In the present study, we investigate the effect of xanthohumol on the viability and stemness of MCF-7/ADR cells. Xanthohumol inhibits viability, induces apoptosis, and arrests the cell cycle of MCF-7/ADR cells in a dose-dependent manner; in addition, xanthohumol sensitizes the inhibition effect of doxorubicin on MCF-7/ADR cells. Interestingly, we also find that xanthohumol can reduce the stemness of MCF-7/ADR cells evidenced by the xanthohumol-induced decrease in the colony formation, the migration, the percentage of side population cells, the sphere formation, and the down-regulation of stemness-related biomarkers. These results demonstrate that xanthohumol is a promising compound targeting the doxorubicin resistant breast cancer cells and regulating their stemness, which, therefore, will be applied as a potential candidate for the development of a doxorubicin-resistant breast cancer agent and combination therapy of breast cancer.

  15. FHL2 Antagonizes Id1-Promoted Proliferation and Invasive Capacity of Human MCF-7 Breast Cancer Cells

    Institute of Scientific and Technical Information of China (English)

    Wei-dong Han; Zhi-qiang Wu; Ya-li Zhao; Yi-ling Si; Ming-zhou Guo; Xiao-bing Fu

    2010-01-01

    Objective:FHL2 was previously identified to be a novel interacting factor of Id family proteins.The aim of this study was to investigate,the effects of FHL2 on Id1-mediated transcriptional regulation activity and its oncogenic activity in human breast cancer cells.Methods:Cell transfection was performed by Superfect reagent.Id1 stably overexpressed MCF-7 cells was cloned by G418 screening.The protein level of Id1 was detected by western blot analysis.Dual relative luciferase assays were used to measure the effect of E47-mediated transcriptional activity in MCF-7 human breast cancer cells.MTT assay was used to measure cell proliferation.Transwell assay was used to measure the invasive capacity of MCF-7 cancer cells.Results:The basic helix-loop-helix(bHLH)factor E47-mediated transcription activity was markedly repressed by Id1 in MCF-7 cells.This Id1-mediated repression was effectively antagonized by FHL2 transduction.Overexpression of Id1 markedly promoted the proliferation rate and invasive capacity of MCF-7 cells; however,these effects induced by Id1 were significantly suppressed by overexpression of FHL2 in cells.Conclusion:FHL2 can inhibit the proliferation and invasiveness of human breast cancer cells by repressing the functional activity of Id1.These findings provide the basis for further investigating the functional roles of FHL2-Id1 signaling in the carcinogenesis and development of human breast cancer.

  16. Oroxylin A inhibits hypoxia-induced invasion and migration of MCF-7 cells by suppressing the Notch pathway.

    Science.gov (United States)

    Cheng, Yao; Zhao, Kai; Li, Guojun; Yao, Jing; Dai, Qinsheng; Hui, Hui; Li, Zhiyu; Guo, Qinglong; Lu, Na

    2014-08-01

    Tumor invasion and migration obstructs the treatment and prognosis of cancer. In this research, we investigated the effect of oroxylin A, a natural compound extracted from Scutellaria radix, the root of Scutellaria baicalensis, on inhibition of the invasion and migration of three different tumor cell lines: MCF-7, DU145, and HepG2. The results suggested that oroxylin A could inhibit hypoxia-induced migration and invasion of the three cell lines mentioned above. To study the detailed mechanisms, studies were carried out on MCF-7 cells and it was found that oroxylin A could regulate the expression of related markers in MCF-7 cells including E-cadherin, N-cadherin, and Vimentin. It was also found that oroxylin A inhibited the hypoxia-induced invasion and migration of MCF-7 cells by suppressing the Notch pathway. Oroxylin A inhibited N1ICD translocating to the nucleus and binding to epithelial-mesenchymal transition-related transcription factor Snail, thus suppressing the invasion and migration of MCF-7 cells. Therefore, oroxylin A is expected to be a promising candidate for antimetastasis treatment through suppression of the hypoxia-induced Notch pathway.

  17. Synthetic phosphoethanolamine induces cell cycle arrest and apoptosis in human breast cancer MCF-7 cells through the mitochondrial pathway.

    Science.gov (United States)

    Ferreira, Adilson Kleber; Meneguelo, Renato; Pereira, Alexandre; Filho, Otaviano Mendonça R; Chierice, Gilberto Orivaldo; Maria, Durvanei Augusto

    2013-07-01

    Phosphoethanolamine (Pho-s) is a compound involved in phospholipid turnover, acting as a substrate for many phospholipids of the cell membranes. In a recent study, we showed that Pho-s has antitumor effect in the several tumor cells. In this study we evaluated the antitumor activity of synthetic Pho-s on MCF-7 breast cancer cells. Here we demonstrate that Pho-s is cytotoxic to MCF-7 cells in a dose-dependent manner, while it is cytotoxic to MCF10 only at higher concentrations. In addition, Pho-s induces a disruption in mitochondrial membrane potential (Δψm). Furthermore, Pho-s induces mitochondria aggregates in the cytoplasm and DNA fragmentation of MCF-7 cells visualized by confocal microscopy. In agreement with the reduction on Δψm, we showed that Pho-s induces apoptosis followed by an increase in cytochrome c expression and capase-3-like activity in MCF-7 cells. Our results demonstrate that Pho-s induces a cell cycle arrest in the G1 phase through an inhibition of cyclin D1 and stimulates p53. An additional highlight of this study is the finding that Pho-s inhibits Bcl-2, inducing apoptosis through the mitochondrial pathway. Taken together, these results show that Pho-s is a promising compound in the fight against cancer. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  18. Overexpression of Cell Surface Cytokeratin 8 in Multidrug-Resistant MCF-7/MX Cells Enhances Cell Adhesion to the Extracellular Matrix

    Directory of Open Access Journals (Sweden)

    Fang Liu

    2008-11-01

    Full Text Available Accumulating evidence suggests that multiple complex mechanisms may be involved, simultaneously or complementarily, in the emergence and development of multidrug resistance (MDR in various cancers. Cell adhesion-mediated MDR is one such mechanism. In the present study, we initially observed increased cell adhesion to extracellular matrix proteins by the MDR human breast tumor cell line MCF-7/MX compared to its parental cells. We then used a strategy that combined antibody-based screening technique and mass spectrometry-based proteomics to identify membrane proteins that contribute to the enhanced adhesion of MCF-7/MX cells. Using MCF-7/MX cells as immunogen, we isolated a mouse monoclonal antibody, 9C6, that preferentially reacts with MCF-7/MX cells over the parental MCF-7 cells. The molecular target of 9C6 was identified as cytokeratin 8 (CK8, which was found to be overexpressed on the cell surface of MCF-7/MX cells. We further observed that down-regulation of cell surface levels of CK8 through siRNA transfection significantly inhibited MCF-7/MX cell adhesion to fibronectin and vitronectin. In addition, anti-CK8 siRNA partially reversed the MDR phenotype of MCF-7/MX cells. Taken together, our results suggest that alterations in the expression level and cellular localization of CK8 may play a significant role in enhancing the cellular adhesion of MDR MCF-7/MX cells.

  19. Analytical Approximate Solutions for the Cubic-Quintic Duffing Oscillator in Terms of Elementary Functions

    OpenAIRE

    A. Beléndez; ALVAREZ, M. L.; Francés, J.; S. Bleda; Beléndez, T.; Nájera, A.; Arribas, E.

    2012-01-01

    Accurate approximate closed-form solutions for the cubic-quintic Duffing oscillator are obtained in terms of elementary functions. To do this, we use the previous results obtained using a cubication method in which the restoring force is expanded in Chebyshev polynomials and the original nonlinear differential equation is approximated by a cubic Duffing equation. Explicit approximate solutions are then expressed as a function of the complete elliptic integral of the first kind and the Jacobi ...

  20. Quantum-Carnot engine for particle confined to cubic potential

    Science.gov (United States)

    Sutantyo, Trengginas Eka P.; Belfaqih, Idrus H.; Prayitno, T. B.

    2015-09-01

    Carnot cycle consists of isothermal and adiabatic processes which are reversible. Using analogy in quantum mechanics, these processes can be well explained by replacing variables in classical process with a quantum system. Quantum system which is shown in this paper is a particle that moves under the influence of a cubic potential which is restricted only to the state of the two energy levels. At the end, the efficiency of the system is shown as a function of the width ratio between the initial conditions and the farthest wall while expanding. Furthermore, the system efficiency will be considered 1D and 2D cases. The providing efficiencies are different due to the influence of the degeneration of energy and the degrees of freedom of the system.

  1. Gauge Fixing of Modified Cubic Open Superstring Field Theory

    CERN Document Server

    Kohriki, Maiko; Kunitomo, Hiroshi

    2011-01-01

    The gauge-fixing problem of modified cubic open superstring field theory is discussed in detail both for the Ramond and Neveu-Schwarz sectors in the Batalin-Vilkovisky (BV) framework. We prove for the first time that the same form of action as the classical gauge-invariant one with the ghost-number constraint on the string field relaxed gives the master action satisfying the BV master equation. This is achieved by identifying independent component fields based on the analysis of the kernel structure of the inverse picture changing operator. The explicit gauge-fixing conditions for the component fields are discussed. In a kind of $b_0=0$ gauge, we explicitly obtain the NS propagator which has poles at the zeros of the Virasoro operator $L_0$.

  2. Quantum-Carnot engine for particle confined to cubic potential

    Energy Technology Data Exchange (ETDEWEB)

    Sutantyo, Trengginas Eka P., E-mail: trengginas.eka@gmail.com; Belfaqih, Idrus H., E-mail: idrushusin21@gmail.com; Prayitno, T. B., E-mail: teguh-budi@unj.ac.id [Department of Physics, State University of Jakarta, Jl. Pemuda No.10, Rawamangun, Jakarta Timur 13220 (Indonesia)

    2015-09-30

    Carnot cycle consists of isothermal and adiabatic processes which are reversible. Using analogy in quantum mechanics, these processes can be well explained by replacing variables in classical process with a quantum system. Quantum system which is shown in this paper is a particle that moves under the influence of a cubic potential which is restricted only to the state of the two energy levels. At the end, the efficiency of the system is shown as a function of the width ratio between the initial conditions and the farthest wall while expanding. Furthermore, the system efficiency will be considered 1D and 2D cases. The providing efficiencies are different due to the influence of the degeneration of energy and the degrees of freedom of the system.

  3. Perbaikan Metode Penghitungan Debit Sungai Menggunakan Cubic Spline Interpolation

    Directory of Open Access Journals (Sweden)

    Budi I. Setiawan

    2007-09-01

    Full Text Available Makalah ini menyajikan perbaikan metode pengukuran debit sungai menggunakan fungsi cubic spline interpolation. Fungi ini digunakan untuk menggambarkan profil sungai secara kontinyu yang terbentuk atas hasil pengukuran jarak dan kedalaman sungai. Dengan metoda baru ini, luas dan perimeter sungai lebih mudah, cepat dan tepat dihitung. Demikian pula, fungsi kebalikannnya (inverse function tersedia menggunakan metode. Newton-Raphson sehingga memudahkan dalam perhitungan luas dan perimeter bila tinggi air sungai diketahui. Metode baru ini dapat langsung menghitung debit sungaimenggunakan formula Manning, dan menghasilkan kurva debit (rating curve. Dalam makalah ini dikemukaan satu canton pengukuran debit sungai Rudeng Aceh. Sungai ini mempunyai lebar sekitar 120 m dan kedalaman 7 m, dan pada saat pengukuran mempunyai debit 41 .3 m3/s, serta kurva debitnya mengikuti formula: Q= 0.1649 x H 2.884 , dimana Q debit (m3/s dan H tinggi air dari dasar sungai (m.

  4. On the undamped vibration absorber with cubic stiffness characteristics

    Science.gov (United States)

    Gatti, G.

    2016-09-01

    In order to improve the performance of a vibration absorber, a nonlinear spring can be used on purpose. This paper presents an analytical insight on the characteristics of an undamped nonlinear vibration absorber when it is attached to a linear spring-mass-damper oscillator. In particular, the nonlinear attachment is modelled as a Duffing's oscillator with a spring characteristics having a linear positive stiffness term plus a cubic stiffness term. The effects of the nonlinearity, mass ratio and frequency ratio are investigated based on an approximate analytical formulation of the amplitude-frequency equation. Comparisons to the linear case are shown in terms of the frequency response curves. The nonlinear absorber seems to show an improved robustness to mistuning respect to the corresponding linear device. However, such a better robustness may be limited by some instability of the expected harmonic response.

  5. Cubic Spline Interpolation Reveals Different Evolutionary Trends of Various Species

    Directory of Open Access Journals (Sweden)

    Li Zhiqiang

    2016-01-01

    Full Text Available Instead of being uniform in each branch of the biological evolutionary tree, the speed of evolution, measured in the number of mutations over a fixed number of years, seems to be much faster or much slower than average in some branches of the evolutionary tree. This paper describes an evolutionary trend discovery algorithm that uses cubic spline interpolation for various branches of the evolutionary tree. As shown in an example, within the vertebrate evolutionary tree, human evolution seems to be currently speeding up while the evolution of chickens is slowing down. The new algorithm can automatically identify those branches and times when something unusual has taken place, aiding data analytics of evolutionary data.

  6. Palladium in cubic silicon carbide: Stability and kinetics

    Science.gov (United States)

    Roma, Guido

    2009-12-01

    Several technological applications of silicon carbide are concerned with the introduction of palladium impurities. Be it intentional or not, this may lead to the formation of silicides. Not only this process is not well understood, but the basic properties of palladium impurities in silicon carbide, such as solubility or diffusion mechanisms, are far from being known. Here the stability and kinetics of isolated Pd impurities in cubic silicon carbide are studied by first principles calculations in the framework of density functional theory. The preferential insertion sites, as well as the main migration mechanisms, are analyzed and presented here, together with the results for solution and migration energies. The early stages of nucleation are discussed based on the properties of isolated impurities and the smallest clusters.

  7. Four-dimensional black holes in Einsteinian cubic gravity

    CERN Document Server

    Bueno, Pablo

    2016-01-01

    We construct static and spherically symmetric generalizations of the Schwarzschild- and Reissner-Nordstr\\"om-(Anti) de Sitter (RN-(A)dS) black-hole solutions in four-dimensional Einsteinian cubic gravity (ECG). The solutions are determined by a single blackening factor which satisfies a non-linear second-order differential equation. Interestingly, we are able to compute independently the Hawking temperature $T$, the Wald entropy $\\mathsf{S}$ and the Abbott-Deser mass $M$ of the solutions analytically as functions of the horizon radius and the ECG coupling constant $\\lambda$. Using these we show that the first law of black-hole mechanics is exactly satisfied. Some of the solutions have positive specific heat, which makes them thermodynamically stable, even in the uncharged and asymptotically flat case.

  8. Structure and energetics of nanotwins in cubic boron nitrides

    Science.gov (United States)

    Zheng, Shijian; Zhang, Ruifeng; Huang, Rong; Taniguchi, Takashi; Ma, Xiuliang; Ikuhara, Yuichi; Beyerlein, Irene J.

    2016-08-01

    Recently, nanotwinned cubic boron nitrides (NT c-BN) have demonstrated extraordinary leaps in hardness. However, an understanding of the underlying mechanisms that enable nanotwins to give orders of magnitude increases in material hardness is still lacking. Here, using transmission electron microscopy, we report that the defect density of twin boundaries depends on nanotwin thickness, becoming defect-free, and hence more stable, as it decreases below 5 nm. Using ab initio density functional theory calculations, we reveal that the Shockley partials, which may dominate plastic deformation in c-BNs, show a high energetic barrier. We also report that the c-BN twin boundary has an asymmetrically charged electronic structure that would resist migration of the twin boundary under stress. These results provide important insight into possible nanotwin hardening mechanisms in c-BN, as well as how to design these nanostructured materials to reach their full potential in hardness and strength.

  9. Linear and cubic dynamic susceptibilities in quantum spin glass

    CERN Document Server

    Busiello, G; Sushkova, V G

    2001-01-01

    The low temperature behaviour of the dynamic nonlinear (cubic) susceptibility chi sub 3 sup ' (omega, T) in quantum d-dimensional Ising spin glass with short-range interactions between spins is investigated in terms of the quantum droplet model and the quantum-mechanical nonlinear response theory is employed. We have revealed a glassy like behaviour of droplet dynamics. The frequency dependence of chi sub 3 sup ' (omega, T) is very remarkable, the temperature dependence is found at very low temperatures (quantum regime). The nonlinear response depends on the tunneling rate for a droplet which regulates the strength of quantum fluctuations. This response has a strong dependence on the distribution of droplet free energies and on the droplet length scale average. Implications for experiments in quantum spin glasses like disordered dipolar quantum Ising magnet LiHo sub x Y sub 1 sub - sub x F sub 4 and pseudospin are noted.

  10. A cubic autocatalytic reaction in a continuous stirred tank reactor

    Energy Technology Data Exchange (ETDEWEB)

    Yakubu, Aisha Aliyu; Yatim, Yazariah Mohd [School of Mathematical Sciences, Universiti Sains Malaysia, 11800 USM, Penang Malaysia (Malaysia)

    2015-10-22

    In the present study, the dynamics of the cubic autocatalytic reaction model in a continuous stirred tank reactor with linear autocatalyst decay is studied. This model describes the behavior of two chemicals (reactant and autocatalyst) flowing into the tank reactor. The behavior of the model is studied analytically and numerically. The steady state solutions are obtained for two cases, i.e. with the presence of an autocatalyst and its absence in the inflow. In the case with an autocatalyst, the model has a stable steady state. While in the case without an autocatalyst, the model exhibits three steady states, where one of the steady state is stable, the second is a saddle point while the last is spiral node. The last steady state losses stability through Hopf bifurcation and the location is determined. The physical interpretations of the results are also presented.

  11. Submicron cubic boron nitride as hard as diamond

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Guoduan; Kou, Zili, E-mail: kouzili@scu.edu.cn, E-mail: yanxz@hpstar.ac.cn; Lei, Li; Peng, Fang; Wang, Qiming; Wang, Kaixue; Wang, Pei; Li, Liang; Li, Yong; Wang, Yonghua [Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065 (China); Yan, Xiaozhi, E-mail: kouzili@scu.edu.cn, E-mail: yanxz@hpstar.ac.cn; Li, Wentao [Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065 (China); Center for High Pressure Science and Technology Advanced Research (HPSTAR), Shanghai 201203 (China); Bi, Yan [Institute of Fluid Physics and National Key Laboratory of Shockwave and Detonation Physic, China Academy of Engineering Physics, Mianyang 621900 (China); Leng, Yang [Department of Mechanical Engineering, Hong Kong University of Science and Technology, Kowloon, Hong Kong (China); He, Duanwei [Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065 (China); Institute of Fluid Physics and National Key Laboratory of Shockwave and Detonation Physic, China Academy of Engineering Physics, Mianyang 621900 (China)

    2015-03-23

    Here, we report the sintering of aggregated submicron cubic boron nitride (sm-cBN) at a pressure of 8 GPa. The sintered cBN compacts exhibit hardness values comparable to that of single crystal diamond, fracture toughness about 5-fold that of cBN single crystal, in combination with a high oxidization temperature. Thus, another way has been demonstrated to improve the mechanical properties of cBN besides reducing the grain size to nano scale. In contrast to other ultrahard compacts with similar hardness, the sm-cBN aggregates are better placed for potential industrial application, as their relative low pressure manufacturing perhaps be easier and cheaper.

  12. PT-Symmetric Cubic Anharmonic Oscillator as a Physical Model

    CERN Document Server

    Mostafazadeh, A

    2004-01-01

    We perform a perturbative calculation of the physical observables, in particular pseudo-Hermitian position and momentum operators, the equivalent Hermitian Hamiltonian operator, and the classical Hamiltonian for the PT-symmetric cubic anharmonic oscillator, $ H=p^1/(2m)+\\mu^2x^2/2+i\\epsilon x^3 $. Ignoring terms of order $ \\epsilon^4 $ and higher, we show that this system describes an ordinary quartic anharmonic oscillator with a position-dependent mass and real and positive coupling constants. This observation elucidates the classical origin of the reality and positivity of the energy spectrum. We also discuss the quantum-classical correspondence for this PT-symmetric system, compute the associated conserved probability density, and comment on the issue of factor-ordering in the pseudo-Hermitian canonical quantization of the underlying classical system.

  13. Enhanced initial protein adsorption on an engineered nanostructured cubic zirconia

    CERN Document Server

    Sabirianov, R F; Namavar, F

    2010-01-01

    Motivated by experimentally observed biocompatibility enhancement of nanoengineered cubic zirconia ZrO2 coatings to mesenchymal stromal cells, we have carried out computational analysis of the initial immobilization of one of known structural fragment of the adhesive protein (fibronectin) on the corresponding surface. We constructed an atomistic model of the zirconia nano-hillock of 3-fold symmetry based on AFM and TEM images. First-principle quantum-mechanical calculations show a substantial variation of electrostatic potential at the hillock due to the presence of surface features such as edges and vertexes. Using an implemented Monte Carlo simulated annealing method we found the orientation of the immobilized protein on the zirconia surface (both flat and nanostructured) and contribution of the each amino acid residue from the protein sequence to the adsorption energy. Accounting for the variation of the dielectric permittivity at the protein-implant interface we use a model distance-dependent dielectric f...

  14. Inverse cubic law of index fluctuation distribution in Indian markets

    CERN Document Server

    Pan, R K; Pan, Raj Kumar; Sinha, Sitabhra

    2006-01-01

    One of the principal statistical features characterizing the activity in financial markets is the distribution of fluctuations in market indicators such as the index. While the developed stock markets such as the New York Stock Exchange (NYSE) have been found to show heavy-tailed fluctuation distribution, there have been claims that emerging markets behave differently. Here we investigate the distribution of several indices from the Indian financial market, one of the largest emerging markets in the world. We have used both tick-by-tick data from the National Stock Exchange (NSE) and daily closing data from both NSE and Bombay Stock Exchange (BSE). We find that the cumulative distribution of index fluctuations has long tails consistent with a power law having exponent $\\alpha \\approx 3$, independent of the time-scale of observation or the market index used for the analysis. This ``inverse cubic law'' is quantitatively similar to what has been observed in developed markets, thereby providing strong evidence th...

  15. Entanglement across a cubic interface in 3+1 dimensions

    Science.gov (United States)

    Devakul, Trithep; Singh, Rajiv R. P.

    2014-08-01

    We calculate the area, edge, and corner Renyi entanglement entropies in the ground state of the transverse-field Ising model, on a simple-cubic lattice, by high-field and low-field series expansions. We find that while the area term is positive and the line term is negative as required by strong subadditivity, the corner contributions are positive in three dimensions. Analysis of the series suggests that the expansions converge up to the physical critical point from both sides. The leading area-law Renyi entropies match nicely from the high- and low-field expansions at the critical point, forming a sharp cusp there. We calculate the coefficients of the logarithmic divergence associated with the corner entropy and compare them with conformal field theory results with smooth interfaces and find a striking correspondence.

  16. Energy Density Bounds in Cubic Quasi-Topological Cosmology

    CERN Document Server

    dS, U Camara; Sotkov, G M

    2013-01-01

    We investigate the thermodynamical and causal consistency of cosmological models of the cubic Quasi-Topological Gravity (QTG) in four dimensions, as well as their phenomenological consequences. Specific restrictions on the maximal values of the matter densities are derived by requiring the apparent horizon's entropy to be a non-negative, non-decreasing function of time. The QTG counterpart of the Einstein-Hilbert (EH) gravity model of linear equation of state is studied in detail. An important feature of this particular QTG cosmological model is the new early-time acceleration period of the evolution of the Universe, together with the standard late-time acceleration present in the original EH model. The QTG correction to the causal diamond's volume is also calculated.

  17. Room temperature quantum emission from cubic silicon carbide nanoparticles.

    Science.gov (United States)

    Castelletto, Stefania; Johnson, Brett C; Zachreson, Cameron; Beke, David; Balogh, István; Ohshima, Takeshi; Aharonovich, Igor; Gali, Adam

    2014-08-26

    The photoluminescence (PL) arising from silicon carbide nanoparticles has so far been associated with the quantum confinement effect or to radiative transitions between electronically active surface states. In this work we show that cubic phase silicon carbide nanoparticles with diameters in the range 45-500 nm can host other point defects responsible for photoinduced intrabandgap PL. We demonstrate that these nanoparticles exhibit single photon emission at room temperature with record saturation count rates of 7 × 10(6) counts/s. The realization of nonclassical emission from SiC nanoparticles extends their potential use from fluorescence biomarker beads to optically active quantum elements for next generation quantum sensing and nanophotonics. The single photon emission is related to single isolated SiC defects that give rise to states within the bandgap.

  18. Spatial 't Hooft loop to cubic order in hot QCD

    CERN Document Server

    Giovannangeli, P

    2002-01-01

    Spatial 't Hooft loops of strength k measure the qualitative change in the behaviour of electric colour flux in confined and deconfined phase of SU (N) gauge theory. They show an area law in the deconfined phase, known analytica lly to two loop order with a ``k-scaling'' law k(N-k). In this paper we comput e the O(g^3) correction to the tension. It is due to neutral gluon fields that get their mass through interaction with the wall. The simple k-scaling is lost in cubic order. The generic problem of non-convexity shows up in this order an d the cure is provided. The result for large N is explicitely given. We show tha t nonperturbative effects appear at O(g^5).

  19. Plasmon polaritons in cubic lattices of spherical metallic nanoparticles

    CERN Document Server

    Lamowski, Simon; Mariani, Eros; Weick, Guillaume; Pauly, Fabian

    2016-01-01

    We investigate theoretically plasmon polaritons in cubic lattices of interacting spherical metallic nanoparticles. Dipolar localized surface plasmons on each nanoparticle couple through the near field dipole-dipole interaction and form collective plasmons which extend over the whole metamaterial. Coupling these collective plasmons in turn to photons leads to plasmon polaritons. We derive within a quantum model general semi-analytical expressions to evaluate both plasmon and plasmon-polariton dispersions that fully account for nonlocal effects in the dielectric function of the metamaterial. Within this model, we discuss the influence of different lattice symmetries and predict related polaritonic gaps within the near-infrared to the visible range of the spectrum that depend on wavevector direction and polarization.

  20. Cubic Derivative Interactions and Asymptotic Dynamics of the Galileon Vacuum

    CERN Document Server

    De Arcia, Roberto; León, Genly; Nucamendi, Ulises; Quiros, Israel

    2015-01-01

    In this paper we apply the tools of the dynamical systems theory in order to uncover the whole asymptotic structure of the vacuum interactions of a galileon model with a cubic derivative interaction term. It is shown that, contrary to what occurs in the presence of background matter, the galileon interactions of vacuum appreciably modify the late-time cosmic dynamics. In particular, a local late-time attractor representing phantom behavior arises which is inevitably associated with a big rip singularity. It seems that the gravitational interactions of the background matter with the galileon screen the effects of the gravitational self-interactions of the galileon, thus erasing any potential modification of the late-time dynamics by the galileon vacuum processes. Unlike other galileon models inspired in the DGP scenario, self-accelerating solutions do not arise in this model.