Quantum walks on two kinds of two-dimensional models

In this paper, we numerically study quantum walks on two kinds of two-dimensional graphs: cylindrical strip and Mobius strip. The two kinds of graphs are typical two-dimensional topological graph. We study the crossing property of quantum walks on these two models. Also, we study its dependence on the initial state, size of the model. At the same time, we compare the quantum walk and classical walk on these two models to discuss the difference of quantum walk and classical walk

Impact of Driving Cycles on Greenhouse Gas (GHG) Emissions, Global Warming Potential (GWP) and Fuel Economy for SI Car Real World Driving

The transport sector is one of the major contributors to greenhouse gas emissions. This study investigated three greenhouse gases emitted from road transport: CO2, N2O and CH4 emissions as a function of engine warm up and driving cycles. Five different urban driving cycles were developed and used including free flow driving and congested driving. An in-vehicle FTIR (Fourier Transform Inferred) emission measurement system was installed on a EURO2 emission compliant SI (Spark Ignition) car for emissions measurement at a rate of 0.5 HZ under real world urban driving conditions. This emission measurement system was calibrated on a standard CVS (Constant Volume Sampling) measurement system and showed excellent agreement on CO2 measurement with CVS results. The N2O and CH4 measurement was calibrated using calibration gas in lab. A MAX710 real time in-vehicle fuel consumption measurement system was installed in the test vehicle and real time fuel consumption was then obtained. The temperatures across the TWC (Three Way Catalyst) and engine out exhaust gas lambda were measured. The GHG (greenhouse gas) mass emissions and consequent GWP (Global Warming Potential) for different urban diving conditions were analyzed and presented. The results provided a better understanding of traffic related greenhouse gas emission profile in urban area and will contribute to the control of climate change

Compact, Low-Profile, Bandwidth-Enhanced Substrate Integrated Waveguide Filtenna

© 2011 IEEE. In this letter, a compact, low-profile, bandwidth-enhanced, dual-cavity substrate integrated waveguide (SIW) filtenna is demonstrated. Two SIW cavities are stacked vertically on top of each other. A complementary split-ring resonator slot is etched in the top surface of the uppermost cavity, causing the top surface to act as a patch antenna. The operational impedance bandwidth is significantly enhanced by merging the three resonances that arise from this configuration. One is introduced by the patch, and the other two are inherently generated by the two cavities. A metallized coupling post is introduced from the ground plane through both cavities to the upper surface to excite the fundamental resonant mode of the patch, as well as to electromagnetically couple the two cavities. The optimized filtenna was fabricated by a standard printed circuit board technology and tested. It has a low profile λ 0 and a compact size 0.62λ 0×0.62λ0 at its center frequency, f0=2.95GHz. The measured results agree well with their simulated values. They demonstrate a 6.3% fractional bandwidth, a maximum realized gain of 6.73 dBi, a flat gain profile within its passband, and an excellent out-of-band selectivity

Particle swarm optimized, 3-d-printed, wideband, compact hemispherical antenna

© 2002-2011 IEEE. A three-dimensional (3-D)-printed, wideband, compact hemispherical-shaped antenna is presented. It consists of a driven strip monopole and several parallel near-field resonant parasitic (NFRP) strips that reside on the surfaces of a hemispherical shell. The monopole strip lies on the interior surface; the NFRP strips lie on the exterior one. This arrangement facilitates the requisite stable near-field capacitive coupling between them over a wide frequency range. The particle swarm optimization algorithm is used to define the lengths and locations of these NFRP strips to achieve its optimized operational bandwidth around 700 MHz given its compact size. The hemispherical shell was 3-D printed with acrylonitrile butadiene styrene resin; the strips were applied to it with silver paste. This prototype was tested. The measured results, in agreement with their simulated values, demonstrate that it achieves a 17.97% -10 dB fractional impedance bandwidth over which stable realized gain values, near 3.5 dBi, are attained. With its low-cost fabrication and attractive performance characteristics, this 3-D printed antenna is suitable for indoor multipath wireless communication systems

A Bandwidth-Enhanced, Compact, Single-Feed, Low-Profile, Multilayered, Circularly Polarized Patch Antenna

© 2002-2011 IEEE. A bandwidth-enhanced, compact, single-feed, low-profile, multilayered, circularly polarized (CP) patch antenna is presented. A corner-truncated patch is introduced as a near-field resonant parasitic element directly beneath a specially engineered radiation patch. Without sacrificing the antenna's low profile and compact size, its presence not only introduces a new pair of orthogonal near-degenerate resonant modes, but also recovers a similar pair from the cross slot of the main patch. With the aid of both circular slots and meander-line slots on these patches, the resulting three pairs of adjacent near-degenerate modes have been successfully combined with the same clockwise polarization to enhance the CP bandwidth by more than a factor of two when compared to the same-height conventional single-layer patch antennas. Measured results are in good agreement with their simulated values and demonstrate that the reported antenna is low-profile: 0.016 λ achieves a -10-dB impedance bandwidth of ∼4.6%, and a 3-dB axial-ratio bandwidth of about 2.33% along with realized gains of 4.5 ± 0.15 dBi, throughout that bandwidth. Analyses of the current distributions are used to explain the contributions of the parasitic patch, and further simulation studies validate our design guidelines and show its advantages

Effect of therapeutic play on pre- and post-operative anxiety and emotional responses in Hong Kong Chinese children: a randomised controlled trial

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Aquaporin-4 and brain edema.

Aquaporin-4 (AQP4) is a water-channel protein expressed strongly in the brain, predominantly in astrocyte foot processes at the borders between the brain parenchyma and major fluid compartments, including cerebrospinal fluid (CSF) and blood. This distribution suggests that AQP4 controls water fluxes into and out of the brain parenchyma. Experiments using AQP4-null mice provide strong evidence for AQP4 involvement in cerebral water balance. AQP4-null mice are protected from cellular (cytotoxic) brain edema produced by water intoxication, brain ischemia, or meningitis. However, AQP4 deletion aggravates vasogenic (fluid leak) brain edema produced by tumor, cortical freeze, intraparenchymal fluid infusion, or brain abscess. In cytotoxic edema, AQP4 deletion slows the rate of water entry into brain, whereas in vasogenic edema, AQP4 deletion reduces the rate of water outflow from brain parenchyma. AQP4 deletion also worsens obstructive hydrocephalus. Recently, AQP4 was also found to play a major role in processes unrelated to brain edema, including astrocyte migration and neuronal excitability. These findings suggest that modulation of AQP4 expression or function may be beneficial in several cerebral disorders, including hyponatremic brain edema, hydrocephalus, stroke, tumor, infection, epilepsy, and traumatic brain injury

Compact, Frequency-Reconfigurable Filtenna with Sharply Defined Wideband and Continuously Tunable Narrowband States

© 1963-2012 IEEE. A compact, frequency-reconfigurable filtenna with sharp out-of-band rejection in both its wideband and continuously tunable narrowband states is presented. It is intended for use in cognitive radio applications. The wideband state is the sensing state and operationally covers 2.35-4.98 GHz. The narrowband states are intended to cover communications within the 3.05-4.39 GHz range, which completely covers the Worldwide Interoperability for Microwave Access (WiMAX) band and the satellite communications C-band. A p-i-n diode is employed to switch between these wide and narrowband operational states. Two varactor diodes are used to shift the operational frequencies continuously among the narrowband states. The filtenna consists of a funnel-shaped monopole augmented with a reconfigurable filter; it has a compact electrical size: 0.235λLL × 0.392λL , where the wavelength λL corresponds to the lower bound of its operational frequencies. The measured reflection coefficients, radiation patterns, and realized gains for both operational states are in good agreement with their simulated values