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This study presents a fast terminal synergetic control (FTSC) scheme to investigate the nonlinear control problem of permanent magnet vernier generator (PMVG)-based variable-speed wind energy conversion systems (WECSs). In wind turbines, better speed tracking and fast dynamic behavior is required to achieve the maximum power extraction. To do this, the FTSC method is firstly proposed to improve the dynamic performance of tracking the speedby, addressing the turbulent wind and uncertainties in the PMVG system, which improves the wind energy extraction efficiency and alleviates mechanical stress over the turbine. Next, the closed-loop FTSC with a macro variable and novel reaching law is presented to enhance the convergence of the speed error signal when it is far from equilibrium in finite time. At this time, the controller’s output is a zero chattering generator torque reference that can operate the system in both below- and above-rated wind conditions, in addition to pitch control. Then, the proposed control method is verified for its effectiveness in energy capture through numerical simulation and experimental verification of a 5 kW direct drive PMVG-based WECS. Finally, comparative results confirm the better performance of the proposed system under transients than other controllers considered in this analysis.

The power system network grows yearly with a large number of nonlinear power generation systems. In this scenario, accurate modeling, control, and monitoring of interface systems and energy conversion systems are critical to the reliability and performance of the overall power system. In this trend, the permanent magnet synchronous generator (PMSG)-based wind turbine systems (WTS) equipped with a full-rated converter significantly contribute to the development of new and renewable energy generation. The various components and control systems involved in operating these systems introduce higher complexity, uncertainty, and highly nonlinear control challenges. To deal with this, state estimation remains an ideal and reliable procedure in the relevant control of the entire WTS. In essence, state estimation can be useful in control procedures, such as low-voltage ride-through operation, active power regulation, stator fault diagnosis, maximum power point tracking, and sensor faults, as it reduces the effects of noise and reveals all hidden variables. However, many advanced studies on state estimation of PMSG-based WTS deal with real-time information of operating variables through filters and observers, analysis, and summary of these strategies are still lacking. Therefore, this article aims to present a review of state-of-the-art estimation methods that facilitate advances in wind energy technology, recent power generation trends, and challenges in nonlinear modeling. This review article enables readers to understand the current trends in state estimation methods and related issues of designing control, filtering, and state observers. Finally, the conclusion of the review demonstrates the direction of future research.

This paper presents a simple reactive power control method using a constant DC-capacitor voltage control (CDVC) block of active power-line conditioners (APLCs) in three-phase four-wire low-voltage feeder (TPFWLVF). The basic principle of the proposed method using a CDVC block is discussed considering the instantaneous active power flowing in the APLC. A digital computer simulation using the PSIM software is implemented. A laboratory-scale prototype is built and proved. Simulation and experimental results confirm that the proposed method with the CDVC block attains the balanced-sinusoidal source currents with a predetermined power factor in TPFWLVFs.

This paper deals with simple harmonics compensation using the constant DC-capacitor voltage-control (CDCVC)-based strategy of an active power-line conditioner (APLC) with a four-leg inverter in three-phase four-wire distribution feeders (TPFWDFs). The basic principle of the CDCVC-based strategy is precisely discussed. Instantaneous active power flow theoretically demonstrates that the CDCVC-based strategy attains sinusoidal and balanced source-side currents at a power factor (PF) of unity. Digital computer simulation with PSIM software is carried out to verify the validity and excellent practicability of the proposed CDCVC-based strategy of the four-leg APLC. A reduced-scale prototype experimental-model is built and tested. Simulation and experimental results demonstrate that the CDCVC-based strategy of the APLC with the four-leg inverter achieves the sinusoidal and balanced source-side currents at a PF of unity.

Background: Carnosine has antioxidative and neuroprotective properties against hypoxic-ischemic (HI) brain injury. Hypothermia is used as a therapeutic tool for HI encephalopathy in newborn infants with perinatal asphyxia. However, the combined effects of these therapies are unknown.Purpose: Here we investigated the effects of combined carnosine and hypothermia therapy on HI brain injury in neonatal rats.Methods: Postnatal day 7 (P7) rats were subjected to HI brain injury and randomly assigned to 4 groups: vehicle; carnosine alone; vehicle and hypothermia; and carnosine and hypothermia. Carnosine (250 mg/kg) was intraperitoneally administered at 3 points: immediately following HI injury, 24 hours later, and 48 hours later. Hypothermia was performed by placing the rats in a chamber maintained at 27°C for 3 hours to induce whole-body cooling. Sham-treated rats were also included as a normal control. The rats were euthanized for experiments at P10, P14, and P35. Histological and morphological analyses, in situ zymography, terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assays, and immunofluorescence studies were conducted to investigate the neuroprotective effects of the various interventional treatments.Results: Vehicle-treated P10 rats with HI injury showed an increased infarct volume compared to sham-treated rats during the triphenyltetrazolium chloride staining study. Hematoxylin and eosin staining revealed that vehicle-treated P35 rats with HI injury had decreased brain volume in the affected hemisphere. Compared to the vehicle group, carnosine and hypothermia alone did not result in any protective effects against HI brain injury. However, a combination of carnosine and hypothermia effectively reduced the extent of brain damage. The results of in situ zymography, TUNEL assays, and immunofluorescence studies showed that neuroprotective effects were achieved with combination therapy only.Conclusion: Carnosine and hypothermia may have synergistic neuroprotective effects against brain damage following HI injury.

Introduction Exercise training (ET) improves endothelial function and arterial stiffness in patients with cardiovascular disease. However, whether ET improves endothelial function and arterial stiffness in patients with atrial fibrillation (AF) is unclear. If it does, for how long the effects are sustained remains to be determined. Methods In a prospective study, 58 patients with AF (age, 62 ± 7 years) were randomized into an ET group for 12 months (CT, n = 13), a group with 6-month detraining after a 6-month ET (DT, n = 15), and a medical treatment only group (MT, n = 30). For ET, cycling on a bicycle ergometer was performed in the DT and CT groups 3 times a week for 6 and 12 months, respectively. Each session started with a 10-minute warmup at 60% to 70% of the maximal heart rate (HRpeak), followed by four 4-minute intervals at 80% to 90% of the HRpeak, with 3 minutes of active recovery at 60% to 70% of the HRpeak between intervals, ending with a 5-minute cooldown period. Peak exercise oxygen consumption (Vo2), intimal-medial thickness (IMT) of the carotid artery measured on high-resolution ultrasonography, and left ventricular function were measured at baseline, after 6 months of training, and after additional 6 months of continuous training or detraining follow-up assessments. In addition, plasma von Willebrand factor (vWF), endothelin-1, nitric oxide, tumour necrosis factor alpha, interleukin-1 beta, interleukin-6, and interleukin-10 levels were measured as indices of endothelial function. Results The 6-month ET increased peak Vo2 (CT: 29.0 ± 6.5 ml/[kg·min] and DT: 26.0 ± 8.2 ml/[kg·min] vs. MT: 23.0 ± 5.2 ml/[kg·min], p = 0.04) and decreased plasma vWF levels (CT: 103.7 ± 30.7 IU/dL and DT: 106.0 ± 31.2 IU/dL vs. MT: 145.0 ± 47.7 IU/dL, p = 0.01). Detraining significantly reduced the ET-induced increase in Vo2 and decreased the vWF to baseline level, although continuous ET maintained changes in Vo2 (CT: 28.1 ± 5.3 ml/[kg·min] and DT: 22.4 ± 6.6 ml/[kg·min] vs. MT: 21.5 ± 4.8 ml/[kg·min], p = 0.043) and in vWF (CT: 84.3 ± 39.1 IU/dL vs. DT: 122.2 ± 27.5 IU/dL and MT: 135.9 ± 50.4 IU/dL, p = 0.014). However, carotid arterial IMT, and resting left ventricular systolic and diastolic functions showed no significant changes, with no inter-group differences after 6 months of training and 6 months of continuous training or detraining. Conclusions The decreased vWF level suggested that ET can be a strong non-pharmacologic option to improve endothelial function in patients with AF. However, it can rapidly lose its effects after detraining. Therefore, physicians should encourage their patients to participate in a continuous exercise program to sustain its benefits in terms of improved exercise capacity and endothelial function in patients with AF.

Over the last few years, improving power extraction from the wind energy conversion system (WECS) under varying wind speeds has become a complex task. The current study presents the optimum maximum power point tracking (MPPT) control approach integrated with neural network (NN)-based rotor speed control and pitch angle control to extract the maximum power from the WECS. So, this study presents a reference model adaptive control (RMAC) for a direct-drive (DD) permanent magnet vernier generator (PMVG)-based WECS under real wind speed conditions. Initially, the RMAC-based rotor speed tracking control is presented with adaptive terms, which tracks a reference model that guarantees the expected exponential decay of rotor speed error trajectory. Then, to reduce the wind speed measurement errors, a recurrent neural network (RNN)-based training model is presented. Moreover, the asymptotic stability of the proposed control method is mathematically proven by Lyapunov theory. In addition, the pitch angle control is presented to efficiently operate the rotor speed within the allowable operating range. Eventually, the proposed control system demonstrates its effectiveness through simulation and experimentation using a prototype of 5 kW DD PMVG-based WECS. After that, the comparative results affirm the superiority of the proposed control method over existing control methods.

N-acetylcysteine (NAC) is known to serve many biological functions including acting as an antioxidant, and electing antiinflammatory effects. Previous reports have revealed that NAC may have neuroprotective effects against the deleterious effects of brain ischemia. Despite of this, the mechanism by which NAC prevents neuronal damage after brain ischemia remains unclear. The current study aimed to investigate this mechanism in a mouse model of transient global brain ischemia. In the present study, mice were subjected to 20 min of transient global brain ischemia, proceeded by intraperitoneal administration of NAC (150 mg/kg) in one group. The mice were then euthanized 72 h after this ischemic insult for collection of experimental tissues. The effect of NAC on neuronal damage and matrix metalloproteinase (MMP)-9 activity were assessed and immunofluorescence, and hippocampal terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay experiments were conducted and results compared between NAC- and vehicle-treated groups. Neuronal damage was primarily observed in the hippocampal CA1 and CA2 regions. In NAC-treated mice, neuronal damage was significantly reduced after ischemia when compared to vehicle-treated animals. NAC also inhibited increased MMP-9 activity after global brain ischemia. NAC increased laminin and NeuN expression and inhibited increases in TUNEL-positive cells, all in the hippocampus. These results suggest that NAC reduces hippocampal neuronal damage following transient global ischemia, potentially via reductions in MMP-9 activity.

L-Deprenyl is selective and irreversible monoamine oxidase B inhibitor, known to have neuroprotective properties. Putrescine, one of polyamine, is thought to be important in the neuronal cell damage associated with various type of excitatory neurotoxicity. We examined the effects of L-deprenyl on the changes in putrescine level and neuronal damage after transient global ischemia in ger-bils. Male Mongolian gerbils weighing 65 - 75 g were used in the experiment. Global ischemia was induced by occlusion of common carotid arteries for 3 min to observe neuronal injury in hippocampal pyramidal cells. L-Deprenyl group was given 10 mg/kg of L-deprenyl intraperitoneally immediately after, 3 h and 6 h after global ischemia. Treated animals were processed in parallel with ischemic animals receiving saline as a vehicle and with sham- operated controls. Hippocampal putrescine level was increased by global ischemia and inhibited by L-deprenyl treatment. In histological findings, counts of viable neurons were made in the pyramidal cell layer of the hippocampal CA1 area 3 days after ischemic insult. The number of viable neurons in the pyramidal cell layer of CA1 area was significantly increased in animals treated with L-deprenyl compared to vehicle-treated ischemic animals (p < 0.05). In terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick endlabeling (TUNEL) assay, semiquantitative analysis of dark-brown neuronal cells was made in the hippocampal CA1 area. There was also a significant difference in the degree of TUNEL staining in the hippocampal CA1 area between vehi-cle-treated and L-deprenyl-treated animals (p < 0.05). These data show L-deprenyl is effective as a prophylactic treatment for neuronal injury when it is administrated before ischemia but a further study need to know the effects of administration of L-deprenyl after ischemia and at given times after reper-fusion.

This paper proposes a new constant de-capacitor voltage control (CDCVC)-based reactive power control strategy for an active power-line conditioner (APLC) in three-phase four-wire distribution feeders. The newly proposed CDCVC-based reactive power control strategy uses only a CDCVC, which is always included in grid-connected inverters, APLCs, etc. The calculation blocks of the fundamental active, reactive and harmonic components on the load side are not required. Thus, the authors propose a simplified strategy for the source-side reactive power control with source-side harmonic current compensation. The instantaneous power flowing into the APLC shows that the newly proposed CDCVC-based reactive power control strategy of the APLC achieves balanced and sinusoidal source-currents with a controlled power factor (PF). Simulation results demonstrate that the balanced and sinusoidal source-currents with a PF of 0.90 are obtained with the newly proposed CDCVC-based reactive power control strategy.

Resveratrol (3,5,4'-trihydroxystilbene) is a natural polyphenol which is rich in grape seeds and skin. Several studies have revealed that resveratrol possesses neuroprotective effects. In the case of global brain ischemia, there are few reports regarding the protective effect of resveratrol. Therefore, the influence of resveratrol on neuronal damage after transient global brain ischemia remains to be clarified. In the current study, C57BL/6 black mice were subjected to 20 min of transient global brain ischemia and followed by 72 h of reperfusion. Resveratrol (20 or 40 mg/kg, once daily, dissolved in 0.5% carboxymethylcellulose) was administered orally for 7 days before ischemia and daily until the mice were euthanized. The effect of lower or higher dose of resveratrol on neuronal damage, matrix metalloproteinase (MMP) activity and in situ DNA fragmentation (TUNEL) assay in the hippocampus after global ischemia was examined. Neuronal damages were remarkable in CA1 and CA2 pyramidal cell layers after global ischemia. In resveratrol-treated mice (40 mg/kg), neuronal damage was significantly reduced compared with vehicle-treated mice. Mice treated with resveratrol showed reduced MMP-9 activity. Resveratrol also inhibited TUNEL staining. These data suggest that resveratrol, a natural polyphenol, reduces hippocampal neuronal cell damage following transient global ischemia by reducing MMP-9 activity.

Primary cilium is a microtubule-based non-motile organelle that plays critical roles in kidney pathophysiology. Our previous studies revealed that the lengths of primary cilia decreased upon renal ischemia/reperfusion injury and oxidative stress, and restored with recovery. Here, we tested the hypothesis that lack of primary cilium causes epithelial to mesenchymal transition (EMT) of kidney tubule cells. We investigated the alteration of length of primary cilia in TGF-β-induced EMT via visualization of primary cilia by fluorescence staining against acetylated α-tubulin. EMT was determined by measuring mesenchymal protein expression using quantitative PCR and indirect fluorescence staining. As a result, TGF-β treatment decreased ciliary length along with EMT. To test whether defect of primary cilia trigger onset of EMT, cilia formation was disturbed by knock down of ciliary protein using siRNA along with/without TGF-β treatment. Knock down of Arl13b and Ift20 reduced cilia elongation and increased expression of EMT markers such as fibronectin, α-SMA, and collagen III. TGF-β-induced EMT was greater as well in Arl13b and Ift20-knock down cells compared to control cells. Taken together, deficiency of primary cilia trigger EMT and exacerbates it under pro-fibrotic signals.

This paper proposes a reactive power control strategy for the active load balancer (ALB) in three-phase four-wire distribution systems. The proposed reactive power control strategy is based on constant DC capacitor voltage control, which is always used in active power line conditioners. Therefore, the proposed reactive power control strategy does not require active, reactive calculation blocks of load currents for the reference source current calculation. Balanced source currents with a predefined power factor can be achieved without unbalanced active and reactive components detection of the load currents. The basic principle of the reactive power control strategy for the ALB is discussed in detail, and then confirmed by digital computer simulation using PSIM software. A prototype experimental model is constructed and tested to validate the feasibility of the proposed control algorithm. Simulation and experimental results demonstrate that balanced source currents with a predefined power factor are achieved in three-phase four-wire distribution systems.

Migration of surviving kidney tubule cells after sub-lethal injury, for example ischemia/reperfusion (I/R), plays a critical role in recovery. Exocytosis is known to be involved in cell migration, and a key component in exocytosis is the highly-conserved eight-protein exocyst complex. We investigated the expression of a central exocyst complex member, Sec10, in kidneys following I/R injury, as well as the role of Sec10 in wound healing following scratch injury of cultured Madin-Darby canine kidney (MDCK) cells. Sec10 overexpression and knockdown (KD) in MDCK cells were used to investigate the speed of wound healing and the mechanisms underlying recovery. In mice, Sec10 decreased after I/R injury, and increased during the recovery period. In cell culture, Sec10 OE inhibited ruffle formation and wound healing, while Sec10 KD accelerated it. Sec10 OE cells had higher amounts of diacylglycerol kinase (DGK) gamma at the leading edge than did control cells. A DGK inhibitor reversed the inhibition of wound healing and ruffle formation in Sec10 OE cells. Conclusively, downregulation of Sec10 following I/R injury appears to accelerate recovery of kidney tubule cells through activated ruffle formation and enhanced cell migration.

This paper deals with a parallel processing uninterruptible power supply (UPS) for sudden voltage fluctuation in power management to integrate power quality improvement, load voltage stabilization and UPS. To reduce the complexity, cost and number of power conversions, which results in higher efficiency, only one voltage-controlled voltage source inverter (VCVSI) is used. The VCVSI is connected in series on the DC battery side and in parallel on the AC grid side with a decoupling inductor. The system provides sinusoidal voltage at the fundamental value of 220V/60Hz for the load during abnormal utility power conditions or grid failure. Also, the system can be operated to mitigate the harmonic current and voltage demand from nonlinear loads and provide voltage stabilization for loads when sudden voltage fluctuation occur, such as sag and swell. The experimental results confirm the system protects against outages caused by abnormal utility power conditions and sudden voltage fluctuations and change.

This paper proposes a new current control strategy that is based on the internal model principle for a current balancer in single-phase three-wire distribution systems. The proposed current control strategy includes a sinusoidal reference input model to achieve the zero steady-state error tracking. The appropriate control gains of this control strategy can be systematically determined by using a state-feedback controller design method via linear matrix inequalities. The basic principle of the proposed control strategy is discussed in detail, and then confirmed by digital computer simulation using the PSIM software. A prototype experimental model is constructed and tested. Experimental results demonstrate that zero steady-state error tracking is achieved by the proposed control strategy. Also, balanced source currents are obtained on the secondary side of a pole-mounted distribution transformer while the load conditions are unbalanced. © 2013 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

Baicalein, a flavonoid derived from Scutellaria baicalensis Georgi, is known to protect neural tissue from damage. Several studies have found that baicalein reduces brain infarction following focal brain ischaemia. However, there are few reports on the protective effects of baicalein following global brain ischaemia. Therefore, the current study was designed to address the effects of baicalein on neuronal damage and matrix metalloproteinase (MMP; gelatinase) activity in the hippocampus after transient global ischaemia. C57BL/6 mice were subjected to transient global brain ischaemia for 20 min and sacrificed 72 h after ischaemic insult. Baicalein (200 mg/kg, once daily, as a suspension in 0.5% carboxymethylcellulose) or an equal volume of vehicle was orally administered to the mice from 7 days prior to the ischaemic insult until sacrifice. After global ischaemia neuronal damage was significant in CA1 and CA2 pyramidal cell layers. In baicalein-treated mice, neuronal damage from the ischaemic insult was significantly less than that in vehicle-treated mice. Baicalein administration also inhibited MMP-9 activity in the hippocampus. These data demonstrate that baicalein reduces hippocampal neuronal damage after transient global ischaemia. Besides its possible protective mechanisms, the protective role of baicalein against global ischaemia may operate, at least in part, through the inhibition of MMP-9 activity. Copyright © 2012 John Wiley & Sons, Ltd.

Lighting represents a significant component of commercial buildings, particularly office buildings. Fluorescent lighting is invariably used in all commercial, industrial and residential areas. A significant amount of lighting energy is wasted every day by leaving the lights on and not utilizing daylight energy. However, if daylight illuminance can be harnessed, this will reduce the electricity consumption of fluorescent lamps and save energy. This paper explains possible significant savings in lighting energy consumption and hence in costs, without reducing the performance and visual satisfaction in office or industrial buildings. It is proposed to obtain energy saving by reducing the supply voltage without degradation in lighting performance. Experimental results confirm that as much as 20% of electrical energy can be saved by reducing about 9% of the supply voltage, without noticeably affecting light output while complying with lighting standard limits.

This paper presents a comparative analysis of the parallel operation of different switches in a DC/DC converter. In high power applications, multi-switch PWM power conditioners may be preferred despite a higher component count, due to the absence of low frequency filters, reduced switching losses and fault tolerance. The paper demonstrates how current sharing (CSH) and time sharing (TSH) lead to the reduction of switching stress in the parallel operation of switches in any converter. The solutions proposed in this study can be applied on different scales to other power conditioners for DC/DC converter systems. Discussions of the concepts, hypotheses and computer simulations are verified by 1 kW experimental results.

Background and Purpose— Vascular pathology and Alzheimer disease (AD) pathology have been shown to coexist in the brains of dementia patients. We investigated how cognitive impairment could be exacerbated in a rat model of combined injury through the interaction of chronic cerebral hypoperfusion and amyloid beta (Aβ) toxicity. Methods— In Wistar rats, chronic cerebral hypoperfusion was modeled by permanent occlusion of bilateral common carotid arteries (BCCAo). Further, AD pathology was modeled by bilateral intracerebroventricular Aβ (Aβ toxicity) using a nonphysiological Aβ peptide (Aβ 25 to 35). The experimental animals were divided into 4 groups, including sham, single injury (Aβ toxicity or BCCAo), and combined injury (BCCAo-Aβ toxicity) groups (n=7 per group) . Cerebral blood flow and metabolism were measured using small animal positron emission tomography. A Morris water maze task, novel object location and recognition tests, and histological investigation, including neuronal cell death, apoptosis, neuroinflammation, and AD-related pathology, were performed. Results— Spatial memory impairment was synergistically exacerbated in the BCCAo–Aβ toxicity group as compared to the BCCAo or Aβ toxicity groups ( P Conclusion— Our experimental results support a clinical hypothesis of the deleterious interaction between chronic cerebral hypoperfusion and Aβ toxicity. Chronic cerebral hypoperfusion-induced perturbation in the equilibrium of AD-related pathology may exacerbate cognitive impairment in a rat model of combined injury.

Green tea polyphenol (-)-epigallocatechin gallate (EGCG) has been reported to reduce neuronal damage after cerebral ischemic insult. EGCG is known to reduce matrix metalloproteinase (MMP) activity. MMP can play an important role in the pathophysiology of neurological disorders including cerebral ischemia. The purpose of the current study was to investigate whether EGCG shows an inhibitory effect on MMP activity and neural tissue damage following transient focal cerebral ischemia. In the present study, C57BL/6 mice were subjected to 80 min of focal ischemia induced by middle cerebral artery occlusion (MCAO). Animals were killed 24 h after ischemia. EGCG (50 mg/kg) was administered intraperitoneally immediately after ischemia. Gelatin gel zymography showed an increase in the active form of MMP-9 after ischemia. EGCG reduced ischemia-induced up-regulation of the active form of MMP-9. In in situ zymography, EGCG reduced up-regulation of gelatinase activity induced by cerebral ischemia. Co-incubation with EGCG reduced gelatinase activity directly in postischemic brain section. In 2,3,5-triphenyltetrazolium chloride (TTC) assay, brain infarction was remarkable in the middle cerebral artery territory after focal cerebral ischemia. In EGCG-treated mice, infarct volume was significantly reduced compared with vehicle-treated mice. These results demonstrate that EGCG, a green tea polyphenol, may reduce up-regulation of MMP-9 activity and neuronal damage following transient focal cerebral ischemia. In addition to its antioxidant effect, MMP-9 inhibition might be a possible mechanism potentially involved in the neuroprotective effect of a green tea polyphenol, EGCG.

There have been several reports on the progress of the caloric response of vestibular neuritis, but little is known about the recovery of canal paresis (CP) of a vascular cause. This study found that the caloric response normalised in 20 (67%) of 30 patients with CP associated with posterior circulation ischaemic stroke who were followed for at least 1 year (mean, 42.5 months; range, 14-85 months). The most commonly infarcted territory on brain MRI associated with CP was in the distribution of the anterior inferior cerebellar artery (26/30, 87%). None of the patients who were followed for >5 years after the onset of vertigo showed persistent CP. Residual dizziness did not differ significantly between patients with or without CP at the final follow-up. These findings suggest that CP associated with posterior circulation ischaemic stroke often has a good long-term outcome. Following patients for at least 5 years increases the likelihood of normalisation of the vestibular response to caloric stimulation.

We propose a transflective dual mode liquid crystal display, which is composed of a transmissive part for dynamic mode and a reflective part for a memory mode in a pixel. The proposed configuration has single cell gap and single rubbing direction in both parts. In order to make the reflectance minimized and maximized for dark and bright states of memory part, the parameters of LC layer and retardation film are optimized by using the Jones matrix method. Moreover, the operating voltage of dynamic part is found to depend on the retardation values of compensation films. With this configuration, the dynamic and memory modes show high contrast ratio of 1100:1 and 20:1, respectively, by calculation, while 220:1 and 10:1, respectively, by experiment.

Objectives To document otolith dysfunction in patients with posterior inferior cerebellar artery (PICA) territory cerebellar infarction. Methods From March to October 2006, 14 consecutive patients with PICA territory cerebellar infarctions (brainstem spared) diagnosed by brain MRI from the acute stroke registry at the Keimyung University Dongsan Medical Center were enrolled within 12 days of onset (mean 4.0 days). Otolith function tests included ocular torsion (OT), skew deviation, and subjective visual vertical (SVV) were performed. The extent of the cerebellar infarction was determined by previously validated MR anatomical templates. Results All patients had an abnormal posture as a result of otolithic dysfunction. Eleven patients (79%) had at least one otolith-related test abnormality: abnormal tilt of SVV (79%), abnormal OT (29%), or skew deviation (21%). Two common patterns of otolith dysfunction were identified based on whether or not the nodulus was infarcted: 1) ipsilesional SVV tilt (mean 5.0° at binocular viewing) without accompanying abnormal OT or skew deviation (nodulus spared); 2) contralesional SVV tilt (mean 11.3° at binocular viewing) with concomitant abnormal OT and skew deviation (nodulus infarcted). Patients with type 1 infarcts (i.e., nodulus spared) fell toward the side of lesion while patients with type 2 infarcts (i.e., nodulus infracted) fell toward the opposite side. Conclusion Isolated PICA territory cerebellar infarction usually produces two distinct patterns of otolith dysfunction — Ipsilesional SVV tilt and falling without accompanying OT or skew deviation if the nodulus is spared and contralesional SVV tilt and falling with OT and skew deviation if nodulus is infarcted.

Previous studies have demonstrated that (–)-epigallocatechin gallate (EGCG), a green tea polyphenol, protects against ischemia and reperfusion-induced injury in many organ systems. Here, we test the hypothesis that part of EGCG's neuroprotective effects may involve a modulation of matrix metalloproteinases (MMPs) after cerebral ischemia. C57BL/6 mice were subjected to 20 min of transient global cerebral ischemia. EGCG (50 mg/kg) or vehicle (saline) was administered i.p. immediately after ischemia. Brains were examined 3 days after ischemia. The effects of EGCG on MMP (gelatinase) activity and neuronal damage in the hippocampus were assessed. Gelatin gel zymography showed induction of active forms of MMP-9 protein after transient global cerebral ischemia. In situ zymography showed that ischemic gelatinase activity occurred primarily in pyramidal neuronal areas after brain ischemia. Mice treated with EGCG showed significantly reduced gelatinase levels. Neuronal damage was evident in CA1 and CA2 pyramidal sectors, corresponding to TUNEL-positive signals. In EGCG-treated mice, delayed neuronal damage was significantly reduced compared with vehicle-treated mice. These results demonstrate that the green tea polyphenol EGCG suppresses MMP-9 activation and reduces the development of delayed neuronal death after transient global cerebral ischemia in mouse brain. © 2008 Wiley-Liss, Inc.

Pioglitazone, a peroxisome proliferator-activated receptor gamma (PPARgamma) agonist, has shown protective effects against ischemic insult in various tissues. Pioglitazone is also reported to reduce matrix metalloproteinase (MMP) activity. MMPs can remodel extracellular matrix components in many pathological conditions. The current study was designed to investigate whether the neuroprotection of pioglitazone is related to its MMP inhibition in focal cerebral ischemia. Mice were subjected to 90 min focal ischemia and reperfusion. In gel zymography, pioglitazone reduced the upregulation of active form of MMP-9 after ischemia. In in situ zymograms, pioglitazone also reduced the gelatinase activity induced by ischemia. After co-incubation with pioglitazone, in situ gelatinase activity was directly reduced. Pioglitazone reduced the infarct volume significantly compared with controls. These results demonstrate that pioglitazone may reduce MMP-9 activity and neuronal damage following focal ischemia. The reduction of MMP-9 activity may have a possible therapeutic effect for the management of brain injury after focal ischemia.

In this paper, a flux-lock type superconducting fault current limiter (SFCL) integrated with a voltage-controlled voltage source inverter (VC- VSI) is proposed. The suggested equipment, which consists of a flux-lock type SFCL and a VCYSI, can perform the fault current limiting operation from the occurrence of a short-circuit, In addition, it can compensate the reactive power that the nonlinear load requires and also perform the un interruptible power supply (UPS) as well as the load voltage stabilization by controlling the amplitude and the phase of the inverter's output voltage. The specification for a test model was determined and its various functions such as the fault current limiting and the power conditioning operations were presented and analyzed via computer simulation. Through the analytical results based on the computer simulation, the validity of the analysis was confirmed and its multi-operation was discussed.

We propose a novel bistable nematic liquid crystal cell, which has a dual-frequency liquid crystal material and pixel-isolating polymer wall formed by an anisotropic phase separation of a mixture of liquid crystals and UV-curable pre-polymers. The proposed cell has two stable states of left- and right-handed -twist. The switching between the two states is achieved by using a sequential waveform of low and high frequencies. A transmissive bistable liquid crystal display is designed, which achieves high contrast ratio by using the proposed cell and optical films.