1,744 research outputs found

    Book Review: Promising Practices for Engaging Families in Literacy

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    Book Review: Promising Practices for Engaging Families in Literacy by Holly Kreider, Margaret Caspe, and Diana B. Hiatt-Michael. Charlotte, NC: Information Publishing, Inc., 2013, 146 pp., $45.99 (paperback)

    A simple circuit realization of the tent map

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    We present a very simple electronic implementation of the tent map, one of the best-known discrete dynamical systems. This is achieved by using integrated circuits and passive elements only. The experimental behavior of the tent map electronic circuit is compared with its numerical simulation counterpart. We find that the electronic circuit presents fixed points, periodicity, period doubling, chaos and intermittency that match with high accuracy the corresponding theoretical valuesComment: 6 pages, 6 figures, 10 references, published versio

    Adaptive robust control of an omnidirectional mobile platform for autonomous service robots in polar coordinates

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    This paper presents an adaptive robust control method for trajectory tracking and path following of an omni-directional wheeled mobile platform with actuators' uncertainties. The polar-space kinematic model of the platform with three independent driving omnidirectional wheels equally spaced at 120 from one another is briefly introduced, and the dynamic models of the three uncertain servomotors mounted on the driving wheels are also described. With the platform's kinematic model and the motors' dynamic model associated two unknown parameters, the adaptive robust controller is synthesized via the integral backstepping approach. Computer simulations and experimental results are conducted to show the effectiveness and merits of the proposed control method in comparison with a conventional PI feedback control method

    Prokaryotic expression, purification and immunogenicity analysis of CpsD protein from Streptococcus iniae

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    Streptococcus iniae is a major cause of serious bacterial infections in both fish and human beings. Capsular polysaccharide (CPS) of S. iniae is vital to evade phagocytic clearance of the host and serves as an important protective antigen of S. iniae infection in aquatic animals. The CpsD gene was determined to be highly conservative in capsule polysaccharide operon. Prokaryotic expression of the CpsD gene of a clinical isolate of S. iniae from channel catfish and immunogenic examination of the recombinant protein were first described in this essay. The recombinant protein was expressed in the form of inclusion bodies (IBs). Induction conditions in Escherichia coli were optimized with 0.6mM Isopropyl β-D-1-Thiogalactopyranoside at 37°C for 5h after the culture mid-log phase in Luria Bertani (LB) medium. The recombinant protein CpsD was thus expressed and purified by immobilized metal affinity chromatography (IMAC), yielding approximate 582.47 mg the protein per liter culture. Western blot analysis showed that the purified CpsD had reactogenicity. It will possibly reveal more details of capsule synthesis and capsule regulation during various stages of the S. iniae infectious process

    BKB\to K Transition Form Factor up to O(1/mb2){\cal O}(1/m^2_b) within the kTk_T Factorization Approach

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    In the paper, we apply the kTk_T factorization approach to deal with the BKB\to K transition form factor F+,0BK(q2)F^{B\to K}_{+,0}(q^2) in the large recoil regions. The B-meson wave functions ΨB\Psi_B and ΨˉB\bar\Psi_B that include the three-particle Fock states' contributions are adopted to give a consistent PQCD analysis of the form factor up to O(1/mb2){\cal O} (1/m^2_b). It has been found that both the wave functions ΨB\Psi_B and ΨˉB\bar\Psi_B can give sizable contributions to the form factor and should be kept for a better understanding of the BB meson decays. Then the contributions from different twist structures of the kaon wavefunction are discussed, including the SUf(3)SU_f(3)-breaking effects. A sizable contribution from the twist-3 wave function Ψp\Psi_p is found, whose model dependence is discussed by taking two group of parameters that are determined by different distribution amplitude moments obtained in the literature. It is also shown that F+,0BK(0)=0.30±0.04F^{B\to K}_{+,0}(0)=0.30\pm0.04 and [F+,0BK(0)/F+,0Bπ(0)]=1.13±0.02[F^{B\to K}_{+,0}(0)/F^{B\to \pi}_{+,0}(0)]=1.13\pm0.02, which are more reasonable and consistent with the light-cone sum rule results in the large recoil regions.Comment: 22 pages and 6 figure

    Impacts of potential future sea level rise on the North branch of the Changjiang river estuary: Quantifying the saline water intrusion in the dry season

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    The phenomenon of global sea level rise (SLR) is undeniable; the 4th IPCC report summaries that the\ud average rise rate of global is 1.8 mm/y since 1961. It is widely taken for granted that SLR will have a severe impact on\ud saline water intrusion processes in estuarine areas. In this paper, by using a two-dimensional hydrodynamic model\ud (MIKE21) and SLR scenarios of 0.5m, 1m and 2m, the impacts of potential future SLR on the North Branch of the\ud Changjiang River Estuary are evaluated by quantifying salinity changes in the dry season. The field data of tidal levels,\ud flow velocities and salinities are employed to validate the model, and the computed results match the observed values\ud well, which indicates that the validated model can provide reliable performances in reproducing the hydrodynamic and\ud saline water intrusion processes in the Changjiang River Estuary, then this validated numerical model was run with\ud present sea level as well as 0.5m, 1m and 2 m SLR scenarios in the dry season respectively. The computations show\ud that: i)the amplification of tidal levels in the upper reach of the South Branch is greater than that in the upper reach of\ud the North Branch with SLR; ii)the ebb and flood discharges in the upper cross-section of the North Branch both respond\ud to SLR with a significant increase trend, with the ebb flow split ratio of the North Branch increasing from 3.8% to\ud 10.3% in 2m SLR scenario; iii)the salinity in the North Branch presents a decrease trend with SLR, and the decreasing\ud extent in the upper reach is 11.4%-33.4%, which is obvious greater than that in the middle and lower reaches.\ud Consequently, it can be concluded that SLR enhances the ebb hydrodynamics and alleviates the saline water intrusion in\ud the North Branch

    Pharmacological treatments in pregnant women with psoriasis in the U.S.A.

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/110872/1/bjd13306.pd

    Computational modelling and experimental characterisation of heterogeneous materials

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    Heterogeneous materials can exhibit behaviour under load that cannot be described by classical continuum elasticity. Beams in bending can show a relative stiffening as the beam depth tends to zero, a size effect. Size effects are recognised in higher order continuum elastic theories such as micropolar elasticity. The drawback of higher order theories is the requirement of addition constitutive relations and associated properties that are often difficult to establish experimentally. Furthermore the finite element method, of great benefit in classical elasticity, has shown limitations when applied to micropolar elasticity. The determination of additional constitutive properties and the computational modelling of micropolar elasticity will be discussed in the context of a model heterogeneous material loaded in simple 3 point bending. The model material was created by drilling holes in aluminium bar in a regular pattern, with the hole axis normal to the plane of bending. The bending tests show that a size effect is present. These results are compared against modelling the detailed beam geometries in the finite element package ANSYS, which again shows the size effect. These two bending test are used to extract the additional micropolar elastic material properties. A comparison is then made against analytical solutions,numerical solutions using a micropolar beam finite element and a micropolar plane stress control volume method.It will be shown that the need for extensive experimental testing to determine the additional constitutive properties may not be necessary with the appropriate use of numerical methods

    Adaptive Robust Self-Balancing and Steering of a Two-Wheeled Human Transportation Vehicle

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    This paper presents adaptive robust regulation methods for self-balancing and yaw motion of a two-wheeled human transportation vehicle (HTV) with varying payload and system uncertainties. The proposed regulators are aimed at providing consistent driving performance for the HTV with system uncertainties and parameter variations caused by different drivers. By decomposing the overall system into the yaw motion subsystems and the wheeled inverted pendulum, two proposed adaptive robust regulators are synthesized to achieve self-balancing and yaw motion control. Numerical simulations and experimental results on different terrains show that the proposed adaptive robust controllers are capable of achieving satisfactory control actions to steer the vehicle
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