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Objective A shorter door-to-puncture time is an independent predictor of good clinical outcomes in patients with acute ischemic stroke (AIS) who undergo mechanical thrombectomy (MT). We recently initiated a protocol for direct care from neurointerventionalists (NIs) in the emergency department (ED) rather than from non-NI neurologists for patients with AIS. Our aim was to investigate whether NIs, as the first point-of-care physicians for stroke in the ED, could shorten door-to-puncture time compared to non-NI neurologists. Methods From January 2020 to December 2020, 50 patients with AIS underwent MT at our hospital. Patients were divided into 2 groups based on the type of physician who provided initial care for stroke in the ED: (a) NI group (n = 20) and (b) non-NI group (n = 30). The door-to-puncture time was retrospectively analyzed. Results The NI group had a significantly shorter door-to-puncture time than the non-NI group (135.2 ± 50.0 minutes vs. 167.2 ± 54.3 minutes, P = 0.040). A door-to-puncture time of ≤120 minutes was more frequently achieved in the NI group than in the non-NI group (55.0% vs. 23.3%, P = 0.022). Multivariable logistic regression analysis revealed that a door-to-puncture time of ≤120 minutes was independently associated with the NI group (adjusted odds ratio 4.098, 95% confidence interval 1.085–15.479, P = 0.037). Conclusions Our study showed that NIs, as the first point-of-care stroke physicians in the ED, were associated with shorter door-to-puncture times. We suggest that NIs should be at the forefront of care for patients with AIS in the acute setting by performing triage and deciding on and performing MT.

The need for soft whole-body tactile sensors is emerging. Piezoresistive materials are advantageous in terms of making large tactile sensors, but the hysteresis of piezoresistive materials is a major drawback. The hysteresis of a piezoresistive material should be attenuated to make a practical piezoresistive soft tactile sensor. In this paper, we introduce a low-hysteresis and low-interference soft tactile sensor using a conductive coated porous elastomer and a structure to reduce interference (grooves). The developed sensor exhibits low hysteresis because the transduction mechanism of the sensor is dominated by the contact between the conductive coated surface. In a cyclic loading experiment with different loading frequencies, the mechanical and piezoresistive hysteresis values of the sensor are less than 21.7% and 6.8%, respectively. The initial resistance change is found to be within 4% after the first loading cycle. To reduce the interference among the sensing points, we also propose a structure where the grooves are inserted between the adjacent electrodes. This structure is implemented during the molding process, which is adopted to extend the porous tactile sensor to large-scale and facile fabrication. The effects of the structure are investigated with respect to the normalized design parameters θ D , θ W , a n d θ T in a simulation, and the result is validated for samples with the same design parameters. An indentation experiment also shows that the structure designed for interference reduction effectively attenuates the interference of the sensor array, indicating that the spatial resolution of the sensor array is improved. As a result, the sensor can exhibit low hysteresis and low interference simultaneously. This research can be used for many applications, such as robotic skin, grippers, and wearable devices.

This study aims to develop a mathematical model to estimate the initial permeate flux of a direct contact membrane distillation process operated with various solids concentrations and Cross Flow Velocities (CFVs). Digestate produced from an anaerobic digestion of livestock wastewater was used as a feed solution for the laboratory scale membrane distillation. Heat transfer coefficients and Nusselt number constants were determined from the distillation experiments performed with various CFVs and feed solution temperatures. An empirical function was derived to reflect the effect of solids concentration on the flux prediction. A statistical analysis supported that the flux predicted by the model fitted very well with the observed flux. By using the developed model, numerical experiments were performed to simulate the flux according to various CFVs, feed solution temperatures, and solids concentrations (0–2200 mg/L). Also, Temperature Polarization Coefficient (TPC) values were calculated by using the results simulated from the numerical experiments. The developed model can be used to predict the initial flux of the membrane distillation process specifically to treat wastewater including high solids contents, and the modeling works can provide more insights on the relationship among flux, CFV, temperature difference, solids concentrations, and heat transfer efficiency.

The excellent Schottky barrier height (SBH) lowering effect of the metal/In0.53Ga0.47As contact is demonstrated to achieve extremely low contact resistance for n-channel InxGa1−xAs-based devices. Severe Fermi-level pinning, caused by large amounts of metal-induced gap states (MIGS) and interface states at the In0.53Ga0.47As surface, can be effectively alleviated, and the large SBH of the metal/In0.53Ga0.47As interface can be significantly lowered by introducing a metal-interlayer-semiconductor (MIS) structure, with the insertion of an Al-doped ZnO (AZO)/Ge interlayer stack between the metal and the In0.53Ga0.47As. The AZO interlayer is used as a heavily doped interlayer to reduce the MIGS, decrease its tunneling thickness, and lower the SBH. Reduction of the interface states at the In0.53Ga0.47As surface is achieved by adopting an ultrathin Ge layer as the surface passivation layer. Furthermore, a favorable interfacial dipole is formed at the AZO/Ge/In0.53Ga0.47As interfaces, which induces further SBH lowering and reduction of the AZO tunneling thickness. A below zero effective SBH for a Ti/AZO (1.2 nm)/Ge (0.5 nm)/n+-In0.53Ga0.47As (Nd = 1 × 1019 cm−3) structure is estimated while the SBH of the Ti/n+-In0.53Ga0.47As structure is 0.27 eV. A specific contact resistivity value of (8.3 ± 2.6) × 10−9 Ω cm2 is achieved for the proposed MIS structure, which is one of the lowest reported values for ohmic contacts to date. This result suggests that the proposed MIS structure, incorporating the AZO/Ge interlayer stack, presents a promising ohmic contact technique for III–V compound semiconductor-based applications.

The current work reports on the effect of annealing temperatures on the morphology and photoluminescence properties of SrAl 2 O 4 : Eu, Dy thin films on sapphire (0001) substrates fabricated by pulsed laser deposition technique. Scanning electronic microscopy and atomic force microscopy were used to investigate the thickness, surface topography, and the morphology of the films. The film deposited using a higher annealing temperature was packed with a uniform layer of larger particle size grains. In addition, the surface of this film was shown to be relatively rougher than that without annealing treatment. An intense green emission, which is attributed to the 5 d -4 f transition of Eu 2 + was observed at about 520 nm from the films with annealing treatment. The effects of annealing treatment on the morphology, topography, and photoluminescence properties are discussed in detail.

Stimuli-responsive materials based on donor–acceptor systems have great potential for sensing applications, including in the solid state. Herein, two push–pull-type molecules, 3,6-di(9H-carbazol-9-yl)pyridazine (CzPyr–H) and 3,6-bis(3,6-dimethoxy-9H-carbazol-9-yl)pyridazine (CzPyr–OMe), each of which contain two carbazole donors and a pyridazine acceptor, were designed and synthesized. The photophysical properties of CzPyr–H and CzPyr–OMe were systematically explored with the aim of switching the absorption and emission properties using trifluoroacetic acid (TFA) as an external analyte, thus realizing volatile acid sensing. The protonation of the central pyridazine unit led to a broad absorption band at longer wavelengths owing to intramolecular charge transfer (ICT), and the emission intensity gradually decreased with increasing TFA concentration. Density functional theory calculations of the HOMO–LUMO energy gaps and orbital distributions of CzPyr–H and CzPyr–OMe as well as their protonated forms, CzPyr–H(H+) and CzPyr–OMe(H+), confirmed that charge transfer occurred in the protonated species. In their aggregated solid states, both compounds showed interesting emission properties including aggregation-enhanced emission (AEE). Utilizing their TFA sensitivity and the AEE phenomenon, CzPyr–H and CzPyr–OMe were successfully applied as fluorescent probes for volatile acid detection and as security ink for information encryption on paper.

We demonstrate the growth of high-quality AlN layers on an AlN nanopillar structure with a patterned SiO2 layer employing horizontal hydride vapor phase epitaxy (HVPE). The use of the AlN nanopillar structure with the patterned SiO2 resulted in improving the crystalline, and overall material properties of the AlN layer. The full width half maximum (FWHM) of peaks corresponding to (002) and (102) reflections of the AlN layer with the nanopillar structure were significantly decreased from 386 and 576 arcsec to 265 and 318 arcsec, respectively, as compared with that of the as-grown AlN layer. The laterally overgrown AlN regions consisted of a continuous well-coalesced layer exhibiting a lower dislocation density than that of the templates used owing to the dislocation blocking and dislocation bending effects. Complementary characterization by transmittance, photoluminescence and Raman spectroscope, indicates further the overall good material properties of the AlN layer grown on the nanopillar structure.

The correlation between the molecular structures of three corrole derivatives (PC: 5,10,15-triphenyl corrole, PFPC: 5,10,15-tris(pentafluorophenyl) corrole, MCPC: 5,10,15-tris(p-methoxycarbonylphenyl)corrole) and their efficiencies for singlet oxygen generation was studied. Introducing electron-withdrawing fluorine atoms into the PC moiety led to a significant enhancement in singlet oxygen generation and facilitated intersystem crossing (ISC) due to enhanced spin-orbit coupling. Cyclic voltammetry experiments revealed a desirable linear relationship between the quenching rate constants and the oxidation potentials of the three corrole derivatives, indicating that the substituent effect is a critical factor governing the oxidation potential of photosensitizers for singlet oxygen generation.

A new contact structure of a metal nitride-double interlayer-semiconductor structure with high thermal stability and ultralow contact resistivity is developed as a next-generation contact scheme via application of interface engineering. As conventional metal–interlayer–semiconductor structures exhibit degradation under thermal stressing owing to the intermixing of materials, three approaches for achieving enhanced thermal stability and ultralow contact resistance are applied. First, a metal nitride with high thermal stability and low reactivity is used as the contact metal. Second, a material with high crystallization temperature is used for the interlayer to prevent the grain boundary diffusion of metal through the interlayer. Lastly, a double interlayer structure is adopted to reduce the Schottky barrier height by utilizing the dipole effect. The corresponding contact was demonstrated to successfully sustain its structure after annealing of 550 ℃. Moreover, it exhibited a specific contact resistivity of 2.20 × 10−8 Ω·cm2, which is a reduction of ~198× and ~2.72× to those of the metal–semiconductor structure and the metal–interlayer–semiconductor structure, respectively. The proposed contact structure and interface engineering techniques in this study provide a valid method to achieve high thermal stability while maintaining low contact resistivity, which is a priority requirement for the emerging nanoscale technology.

In this paper, we have demonstrated nondegenerate n-type doping phenomenon of MoS2 by ZnO. The ZnO doping effects were systematically investigated by Raman spectroscopy and electrical/optical measurements (ID–VG with/without exposure to 520, 655, 785, and 850 nm laser sources). The ZnO doping improved the performance parameters of MoS2-based electronics (Ion↑, μFE↑, n↑) owing to reduction of the effective barrier height between the source and the MoS2 channel. We also monitored the effects of ZnO doping during exposure to air; reduction in ΔVTH of about 75% was observed after 156 h. In addition, the optoelectronic performance of the MoS2 photodetector was enhanced due to the reduction of the recombination rate of photogenerated carriers caused by ZnO doping. In our results, the highest photoresponsivity (about 3.18 × 103 A/W) and detectivity (5.94 × 1012 Jones) of the ZnO-doped photodetector were observed for 520 nm laser exposure.

Air-lift pump can pump liquid and sediments in it by using air-induced lift force. This working principle can be applied to direct carbon fuel cell (DCFC) to carry or transport high-temperature molten fuel or carbonate in the DCFC system. For this application, pumping performance and essential hydrodynamic features of air-lift pump with high submergence ratio are investigated experimentally. In this study, a model system of air-lift pump is designed and made for this purpose, where air is supplied from the bottom of the tube, flows up with a shape of bubble formed, entrains water inside the tube, and discharges it. Flow rate of water discharged from the top is measured with two variable parameters of tube diameter and submergence ratio. Bubble patterns formed in the tube are observed with various combinations of the two parameters and show four distinct patterns depending on air flow rate. A theoretical model is employed to predict discharge flow rate and it is comparable with the experimental results in slug-flow regime. Cracking flow rate, at which discharge of water is initiated, increases as tube diameter increases and submergence ratio decreases. The flow-rate ratio of water to air, i.e., pumping effectiveness, provides a feasible operating range of air-lift pump in terms of the two parameters.

A push–pull supply chain is a hybrid of “push” and “pull” supply chains where semi-finished products are produced by forecasts and “pushed” to a stock point, then are “pulled” by actual customer orders and go through remaining processes to be delivered. In order to design an effective push–pull supply chain, there are two critical issues in the decision making process: how to support decision makers to identify feasible locations for demand fulfillment points based on the product, process, and organizational form of a given enterprise, and how to support decision makers to improve the customer lead time management capability of a push–pull supply chain. In this study, we present a decision support system for designing a push–pull supply chain that 1) incorporates the product, process, and organizational form of a given enterprise; 2) leverages a new hybrid push–pull control model, which enhances the customer lead time management capability; and 3) provides a decision support model that supports decision makers for performing scenario-based analysis in designing a push–pull supply chain. The numerical analysis exhibits how the proposed system can be implemented in the context of a semiconductor supply chain, and subsequently shows that our control model results in substantial improvement of customer lead time management capability over conventional push–pull supply chain designs without a significant inventory cost increase. Also, some experimental results are provided to support decision makers on how to make the transition from the conventional design to the proposed one.

A new video coding algorithm called the first-order-residual/second-order-residual (FOR/SOR) codec is proposed for high definition (HD) video coding in this work. Several advanced coding techniques are adopted in the proposed FOR/SOR codec. For the FOR codec, the well known block-based motion compensated predictive codec is used to exploit temporal and spatial correlations in input image frames. However, it is observed that there still exists structured residual signal after the FOR coding, and a SOR coder is developed to encode residual image frames efficiently. To improve the coding performance furthermore, we consider bit allocation between the FOR and SOR coders at the same block and determine their optimal quantization parameters systematically. It is shown by experimental results that the proposed FOR/SOR codec outperforms H.264/AVC significantly in HD video coding.

Vitis amurensis (Vitaceae) has been reported to have anti-oxidant and anti-inflammatory activities. The present study investigated a methanol extract from the leaf and stem of V. amurensis for neuroprotective effects on cerebral ischemic damage in rats and on excitotoxicity induced by glutamate in cultured rat cortical neurons. Transient focal cerebral ischemia was induced by 2h middle cerebral artery occlusion followed by 24h reperfusion (MCAO/reperfusion) in rats. Orally administered V. amurensis (25-100 mg/kg) reduced MCAO/reperfusion-induced infarct and edema formation, neurological deficits, and neuronal death. Depletion of glutathione (GSH) level and lipid peroxidation induced by MCAO/reperfusion was inhibited by administration of V. amurensis. The increase of phosphorylated mitogen-activated protein kinases (MAPKs), cyclooxygenase-2 (COX-2), and pro-apoptotic proteins and the decrease of anti-apoptotic protein in MCAO/reperfusion rats were significantly inhibited by treatment with V. amurensis. Exposure of cultured cortical neurons to 500 μM glutamate for 12h induced neuronal cell death. V. amurensis (1-50 μg/ml) and (+)-ampelopsin A, γ-2-viniferin, and trans-ε-viniferin isolated from the leaf and stem of V. amurensis inhibited glutamate-induced neuronal death, the elevation of intracellular calcium ([Ca(2+)](i)), the generation of reactive oxygen species (ROS), and changes of apoptosis-related proteins in cultured cortical neurons, suggesting that the neuroprotective effect of V. amurensis may be partially attributed to these compounds. These results suggest that the neuroprotective effect of V. amurensis against focal cerebral ischemic injury might be due to its anti-apoptotic effect, resulting from anti-excitotoxic, anti-oxidative, and anti-inflammatory effects and that the leaf and stem of V. amurensis have possible therapeutic roles for preventing neurodegeneration in stroke.

We introduce a new measurement method of the nonlinear coefficient (NC) of a highly nonlinear fiber based on a four-wave mixing (FWM) technique. The NC along with the fiber's zero-dispersion wavelength (ZDW) was determined from the precise measurement of the pump power dependent optimum pump frequency for peak FWM signal generation conditions. The measurement errors of the NC and ZDW values determined with this method were less than 4.6% and 0.051 nm, respectively.

Context-based adaptive variable length coding (CAVLC) and context-based adaptive binary arithmetic coding (CABAC) are entropy coding methods employed in the H.264/AVC standard. Since these entropy coders are originally designed for encoding residual data, which are zigzag scanned and quantized transform coefficients, they cannot provide adequate coding performance for lossless video coding where residual data are not quantized transform coefficients, but the differential pixel values between the original and predicted pixel values. Therefore, considering the statistical characteristics of residual data in lossless video coding, we newly design each entropy coding method based on the conventional entropy coders in H.264/AVC. From the experimental result, we have verified that the proposed method provides not only positive bit-saving of 8% but also reduced computational complexity compared to the current H.264/AVC lossless coding mode.

(CTG)n.(CAG)n repeats undergo deletion at a high rate in plasmids in Escherichia coli in a process that involves RecA and RecB. In addition, DNA replication fork progression can be blocked during synthesis of (CTG)n.(CAG)n repeats. Replication forks stalled at (CTG)n.(CAG)n repeats may be rescued by replication restart that involves recombination as well as enzymes involved in replication and DNA repair, and this process may be responsible for the high rate of repeat deletion in E. coli. To test this hypothesis (CAG)n.(CTG)n deletion rates were measured in several E. coli strains carrying mutations involved in replication restart. (CAG)n.(CTG)n deletion rates were decreased, relative to the rates in wild type cells, in strains containing mutations in priA, recG, ruvAB, and recO. Mutations in priB and priC resulted in small reductions in deletion rates. In a recF strain, rates were decreased when (CAG)n comprised the leading template strand, but rates were increased when (CTG)n comprised the leading template. Deletion rates were increased slightly in a recJ strain. The mutational spectra for most mutant strains were altered relative to those in parental strains. In addition, purified PriA and RecG proteins showed unexpected binding to single-stranded, duplex, and forked DNAs containing (CAG)n and/or (CTG)n loop-outs in various positions. The results presented are consistent with an interpretation that the high rates of trinucleotide repeat instability observed in E. coli result from the attempted restart of replication forks stalled at (CAG)n.(CTG)n repeats.

Using our process/physics-based compact models (UFDG and UFPDB) in Spice3, we project device characteristics and CMOS performances of nonclassical UTB (FD/SOI and DG) and classical, hypothetical bulk-Si technologies optimized at the Lg = 28 nm node. For the nonclassical MOSFETs (generally with metal gates for Vt control) with the same UTB thickness (tSi), the DG devices are shown to be far superior for SCE control. Also, with regard to speed, the DG devices are generally superior to the FD/SG counterparts because of higher drive currents. However, for light loads and moderate supply voltages, a suboptimal FD/SG design (with the same tSi) for both LOP and HP CMOS applications is found to yield speeds comparable to the DG designs, even though its current drive is much lower and its SCEs are much more severe. This surprising result is explained by the much lower FD/SG intrinsic gate capacitance, CG(VGS). When the FD/SG CMOS design is optimized by aggressive scaling of the UTB thickness, its high-VDD speed diminishes (but is still comparable to that of DG CMOS) because of higher CG at intermediate gate voltages, while its low-VDD speed improves due to increased current. Compared to these nonclassical CMOS designs, the delay of the classical bulk-Si/SG CMOS is predicted to be much longer due mainly to its high CG in the weak/moderate inversion region and relatively low drive current. Finally, we show how FD/SOI CMOS speed is degraded as the BOX is thinned, thereby suggesting that such thinning is not a good design tradeoff.

In this paper, an adaptive nonlinear control design technique is applied to the pitch controller for a missile model, which is aerodynamically controlled. Missile motion is modelled to be nonlinear with unknown parameters and uncertainties. Both unknown parameters and uncertainty bounds are estimated and, based on these estimates, controller parameters are updated at each step. We adopt a design procedure, basically an adaptive backstepping method, which gives the adaptive scheme guaranteeing uniform ultimate boundedness despite of model uncertainties. Computer simulations show that this approach is very promising for the autopilot design for missiles which are highly nonlinear in aerodynamics with unknown parameters.

This paper presents vibration control of a flexible beam structure using a hybrid mount which consists of elastic rubber and piezoelectric stack actuator. After identifying stiffness and damping properties of the rubber and piezoelectric elements, a mechanical model of the hybrid mount is established. The mount model is then incorporated with the beam structure, and the governing equation of motion is obtained in a state space. A sliding mode controller is designed in order to actively attenuate the vibration of the beam structure subjected to high-frequency and small magnitude excitations. The controller is experimentally realized and measured control responses such as acceleration of the beam structure and force transmission through the hybrid mount are evaluated and presented in both frequency and time domains.

In this paper we report a high performance two-stack, multi-color quantum well infrared photodetector (QWIP) composed of an InGaAs/AlGaAs QWIP and an InGaAs/AlGaAs/InGaAs triple-coupled (TC-) QWIP grown on the GaAs substrate for mid- and long-wavelength (MW/LW) infrared (IR) detection. The basic device structure consists of a MWIR QWIP stack with 3 periods of a 43 A In0.3Ga0.7As quantum well and an undoped 300 A Al0.3Ga0.7As barrier and of a LWIR TC-QWIP stack with 5 periods of a 65 A In0.18Ga0.82As quantum well (QW) and two undoped 60 A In0.05Ga0.95As QWs separated by 20 A Al0.08Ga0.92As barriers. The TC-QWIP stack has two response peaks, which are voltage-tunable from 9.2 to 10 μm and 12 to 12.2 μm by the applied bias, respectively. For the LWIR TC-QWIP, a maximum responsivity of 1.96 A/W at 12 μm was obtained at T=40 K, and a maximum detectivity of D*=1.59×1010 cm Hz1/2/W was estimated at Vb=−1.7 V, λp=12 μm, and T=20 K. As for the MWIR QWIP stack a responsivity value greater than 0.3 A/W at λp=5.1 μm was obtained at 120 K, which was found to be nearly independent of the applied bias and temperature.

Type-II superlattices (SLs) based on InAs/GaInSb material systems have been theoretically investigated and optimized to achieve large valence band splitting and thin constituent layers, which are desirable for high detectivity and large absorption coefficient for the long-wavelength infrared (LWIR) and very long-wavelength infrared (VLWIR) detection covering the waveband from 8 to 14 μm and longer. Two approaches have been employed to optimize the SL: the first approach is to increase the InSb mole fraction in GaInSb alloy, keeping the balance between the compression and tension in the SL, and the second approach is to increase the SL thickness ratio, allowing small misfit in the SL. In the first approach, the valence band splitting was found to increase with increasing InSb composition and reached a maximum at 25% of InSb composition for 9 μm and at 30% of InSb composition for 11, 13, 15, 17, and 19 μm peak wavelength, respectively. When the thickness ratio is increased with fixed InSb composition, the valence band splitting has its maximum around a thickness ratio of 2–3, but the advantage of increasing the thickness ratio is obtained only for SL with less than 15% of InSb composition. It was also found in the first approach that higher InSb composition in GaInSb alloy was very efficient in reducing the total thickness of one period of SL up to 35% of InSb mole fraction. In the second approach, the minimum thickness of SL is obtained at the point where the valence band splitting is maximized. However, since the second approach is useful only for InSb composition less than 15%, the reduction of total thickness of SL is less effective than the first approach. Consequently, we can design high performance type-II SL IR detectors by both approaches for LWIR and VLWIR applications.

In this paper, a robust control scheme based on the quaternion feedback for attitude control of missiles employing thrust vector control is proposed. The control law consists of two parts: the nominal feedback part and an additional term for ensuring robustness to the plant uncertainties. For the proposed control scheme, a stability analysis is given and the performance is shown via computer simulation.

The hepatoprotective effects of acetylbergenin were examined against D -galactosamine (GalN)-induced liver damage in rats, compared with that of bergenin reported previously. Acetylbergenin was synthesized from acetylation of bergenin, isolated from Mallotus japonicus, to increase lipophilic and physiological activities. Acetylbergenin was administered orally once daily for 7 days and then GalN (400 mg kg−1, i.p.) was injected at 24 h and 96 h after the final administration of acetylbergenin. Acetylbergenin reduced the elevated serum enzyme activities of alanine/aspartate aminotransferase, sorbitol dehydrogenase and γ -glutamyltransferase and the formation of hepatic malondialdehyde induced by GalN. Acetylbergenin also significantly restored towards normalization the decreased levels of glutathione and the decreased activities of glutathione S-transferase and glutathione reductase induced by GalN. Therefore, these results suggest that acetylbergenin has hepatoprotective effects against GalN-induced hepatotoxicity by inhibiting lipid peroxidation and maintaining an adequate level of GSH for the detoxification of xenobiotics as underlying hepatoprotective mechanisms. In addition, lipophilic acetylbergenin showed more activity in the hepatoprotection than that of the much less lipophilic bergenin reported previously.

The purpose of this study was to characterize behavioral interactions between nitric oxide synthase (NOS) inhibitors and serotonergic 5-HT2 receptors. In the present study, NOS inhibitors, N(G)-nitro-L-arginine, N(G)-nitro-L-arginine methylester, N(G)-monomethyl-L-arginine, 7-nitroindazole, trifluoperazine and NO scavenger, methylene blue markedly enhanced 5-hydroxytryptamine (5-HT)-induced selective serotonergic behavior, the head twitch response (HTR), in mice. However NO generators, sodium nitroprusside, 3-morpholinosydnonimine and S-nitroso-N-acetylpenicillamine as well as NO precursor, L-arginine markedly inhibited 5-HT induced HTR in mice. In the previous study, it was demonstrated that the N-methyl-D-aspartate (NMDA) receptor antagonists markedly enhanced 5-HT-induced selective serotonergic behavior, HTR, whereas NMDA itself inhibited 5-HT-induced HTR in mice. In the present study, it was demonstrated that the inhibition by a NMDA receptor agonist, NMDA of 5-HT-induced HTR was reversed by the treatment with NOS inhibitors, N(G)-nitro-L-arginine and N(G)-nitro-L-arginine methylester. The suppressive action by a NO generator, S-nitroso-N-acetylpenicillamine of 5-HT-induced HTR was also reversed by the treatment with NMDA receptor antagonists, MK-801 and dextromethorphan. These results have shown that the NO system is located down stream of NMDA receptors involved in modulation of 5-HT2-mediated HTR. Therefore, the enhanced effects of NOS inhibitors on 5-HT-induced HTR support experimental evidence for the NO/5-HT2 as well as NMDA/5-HT2 receptor interactions indicating that NO plays an important role in the glutamatergic modulation of the serotonergic function at the 5-HT2 receptor.

In this paper, a new control structure for spacecraft attitude control, which consists of quatemion feedback and dual mode control, is proposed. The quatemion feedback rapidly reorients spacecraft and the dual mode control solves the tradeoff between the fuel conswnption and the accuracy. The dual mode consists of PWPF(Pulse Width Pulse Frequency) modulator and Schmitt trigger. PWPF is used for the coarse control and Schmitt trigger for the fine control. For the proposed control scheme, stability analysis is given and the performance is shown via simulation.

We discuss scaling, renormalization, and universality for critical and subcritical circle maps. Using the structure of the rationals provided by the Farey tree, we construct a pair of renormalization group operators for circle maps with all values of the winding number. In this general formulation, the renormalization equations define a universal invariant set which determines all universal quantities for all cubic maps with all irrational winding numbers. As expected, the manifold of pure rotations defines the subcritical attracting set. We show that the invariant set governing the critical circle maps cannot be embedded in less than 3 dimensions. However, we are able to obtain a differentiable parametrization of the unstable manifold of the critical invariant set, which we believe is universal up to Lipschitz homeomorphisms; the derivative of this function describes the scaling structure of all small gaps in the devil's staircase for all critical maps. Our work can be viewed as providing numerical evidence for Lanford's conjectures on the strange set underlying renormalizations of critical circle maps.