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In this study, the ruthenium dioxide (RuO2) sensing films were prepared by radio frequency sputtering system on the flexible polyethylene terephthalate (PET) and used the screen printer technology to prepare the conducting wires to connect the sensing windows and spread on insulation layer by epoxy which can protect the conducting wires and sensing windows. In the experimental, first, the biosensors were analyzed for the pH value of the hysteresis reaction (5.651 mV). Second, the magnetic beads and glucose oxidase (GOD) were combined with covalent binding, and coated on the sensing windows by Nafion. It was used to measure the linearity and sensitivity, as well as analyzed the different volume ratios of Nafion and GOD and the stability of the glucose biosensors. The results showed that the glucose biosensors exhibit a high linearity (0.987), sensitivity (29.652 mV/mM) by the volume ratio of Nafion to GOD is 3:4 and present high stability, which can be measured the glucose solution, repeatedly.

This study presents a novel process for fabricating microfluidic device by screen-printed technology to obtain the low cost and less time wasting. The poly-dimethylsiloxane (PDMS) was used as the upper cover of microfluidic device. Besides, the glucose sensing membrane was evaluated by the electrochemical impedance spectroscopy (EIS) to determine that the glucose sensing film had been modified successfully. In the concentration ranging from 100 mg/dL to 500 mg/dL of glucose solution, the sensitivity and linearity of ruthenium dioxide (RuO2) sensing membrane via microfluidic device were 0.256 mV(mg/dL)-1 and 0.998, respectively, which was better than at the static conditions. All experimental results demonstrated that the arrayed flexible glucose biosensor had good electrochemical characteristics including high sensitivity, good reproducibility and long-term stability.

The objective of this study is to investigate the influence of surface roughness on electrochromic characteristics. The rough surface of indium tin oxide/glass (ITO/Glass) was prepared by wet etching. And the poly (3-methylthiophene) (PMeT) has been deposited on ITO/Glass by potentiostatic method. The electrochromic behaviors of the PMeT/ITO/Glass were performed in 0.1 M lithium perchlorate (LiClO4)/propylene carbonate (PC) electrolyte. Compared with the oxalic acid ((COOH)2·H2O) and ferric chloride + hydrochloric acid (FeCl3+HCl) solutions, the ITO/Glass has high surface roughness when the ITO/Glass was etched in (COOH)2·H2O solution. The PMeT/ITO/Glass has the best transmittance variation (ΔT(%)) (25 %) at 450 nm after the ITO/Glass was etched in (COOH)2·H2O solution for 160 sec. And, the PMeT/ITO/Glass has the best transmittance variation (ΔT(%)) (5 %) at 650 nm after the ITO/Glass was etched in FeCl3+HCl solution for 60 sec. Furthermore, the experimental results observed that the color of PMeT/ITO/Glass was changed from blue (oxidation state) to red (reduction state).

In this study, the mutual electrolyte structure of arrayed flexible dye-sensitized solar cell (FDSSC) was used to decrease the internal impedance. The ITO-PET substrate was etched the conductive layer (ITO) by etching solution, which designed arrayed pattern. TiO2 thin film was fabricated on the arrayed conductive substrate by spin-coating. The arrayed flexible dye-sensitized solar cell with mutual electrolyte structure can be well avoided electrolyte to contact ITO layer directly, which increased photovoltaic conversion efficiency. The arrayed flexible dye-sensitized solar cell with mutual electrolyte structure has excess electrolyte, which can obtain sufficient redox from crevice between cell and cell of mutual electrolyte structure. Compared different distances between cell and cell of mutual electrolyte structure, and the experimental results were confirmed by photovoltaic characteristic parameters and Electrochemical Impedance Spectroscopy (EIS). According to the experimental results, the distance of 1 mm has optimal characteristic parameter, which the open circuit voltage (VOC) is 0.81 V, the short circuit current density (JSC) is 1.70 mA/cm2, and the photovoltaic conversion efficiency is 0.37 %.

In this paper, analysis of circulating currents of paralleled single-phase boost converter systems is presented. The DC loop and AC loop circulating currents are clearly explained. In order to eliminate the DC loop circulating currents and reduce switching losses, a simplified PWM strategy is adopted in a paralleled single-phase boost converter. Based on the analysis of circulating currents, common mode circulating current (CMCC) and differential mode circulating current (DMCC) are defined. Then, CMCC and DMCC compensator in a centralized control scheme are proposed to reduce the common-mode and differential-mode circulating currents in the parallel system operated in both rectifier mode and inverter mode for micro-grid applications. Some simulation results are carried out to verify the validity of the proposed control scheme. In addition, a prototype system is constructed to facilitate the theoretical results as verification. From simulation and experimental results, the proposed control scheme can indeed reduce the circulating currents under equal and/or different power rating condition in the parallel system.

In this paper, a novel simplified PWM strategy is proposed for the bidirectional ac/dc single-phase converter in the micro-grid system. Then, the operation mechanism of the novel simplified PWM is clearly explained. It is obvious that the switching numbers of the novel simplified PWM strategy are only one-fourth that of the conventional unipolar PWM and bipolar PWM. Based on the novel simplified PWM strategy, a feasible feed-forward control scheme is also developed to achieve better performance in both rectifier mode and inverter mode operation compared with the conventional dual control scheme. In addition, the proposed simplified PWM strategy with proposed feed-forward control scheme possesses lower total harmonic distortion than bipolar PWM, and higher efficiency than unipolar and bipolar PWM. Finally, a prototype system is constructed, and the control scheme is implemented using FPGA Spartan-3E XC3S250E. Both simulation and experimental results verify the validity of the proposed PWM strategy and the control scheme.

In this paper, the analysis of circulating currents of a paralleled single-phase boost rectifier system is presented. The DC loop and AC loop circulating currents are clearly explained. Based on the analysis of circulating currents, common mode circulating current (CMCC) and differential mode circulating current (DMCC) are clearly defined. Then, CMCC and DMCC compensators in a centralized control scheme are proposed to reduce the common-mode and differential-mode circulating currents in the parallel rectifier system. Finally, a prototype system is constructed and some experimental results are carried out to verify the validity of the proposed control scheme. From experimental results, the proposed control scheme can indeed reduce the circulating currents under different power rating condition in the parallel system.

A simple modular passive ripple mirror circuit (PRMC) is proposed for eliminating the inherent high frequency current ripple of switching pulse-width modulation (PWM) inverters. The proposed passive circuit is robust in the sense of without containing neither any power semiconductor switch nor any extra control. Only the reflected high frequency ripples are automatically induced and processed for proper cancellation with the original ripples. It turns out that not only the output power quality can be enhanced but also the inductance of the main power circuit can be reduced greatly. As an example, a single-phase PWM inverter is chosen for illustrating the effectiveness of the proposed PRMC. Experimental results show that the proposed PRMC can indeed achieve the desired performance.

The purpose of this investigation was to test an amino acid mixture on glucose tolerance in obese Zucker rats [experiment (Exp)-1] and determine whether differences in blood glucose were associated with alterations in muscle glucose uptake [experiment (Exp)-2]. Exp-1 rats were gavaged with either carbohydrate (OB-CHO), carbohydrate plus amino acid mixture (OB-AA-1), carbohydrate plus amino acid mixture with increased leucine concentration (OB-AA-2) or water (OB-PLA). The glucose response in OB-AA-1 and OB-AA-2 were similar, and both were lower compared to OB-CHO. This effect of the amino acid mixtures did not appear to be solely attributable to an increase in plasma insulin. Rats in Exp-2 were gavaged with carbohydrate (OB-CHO), carbohydrate plus amino acid mixture (OB-AA-1) or water (OB-PLA). Lean Zuckers were gavaged with carbohydrate (LN-CHO). Fifteen minutes after gavage, a radiolabeled glucose analog was infused through a catheter previously implanted in the right jugular vein. Blood glucose was significantly lower in OB-AA-1 compared to OB-CHO while the insulin responses were similar. Glucose uptake was greater in OB-AA-1 compared with OB-CHO, and similar to that in LN-CHO in red gastrocnemius muscle (5.15 ± 0.29, 3.8 ± 0.27, 5.18 ± 0.34 µmol/100 g/min, respectively). Western blot analysis showed that Akt substrate of 160 kDa (AS160) phosphorylation was enhanced for OB-AA-1 and LN-CHO compared to OB-CHO. These findings suggest that an amino acid mixture improves glucose tolerance in an insulin resistant model and that these improvements are associated with an increase in skeletal muscle glucose uptake possibly due to improved intracellular signaling.

In this study, real-time motoring system was fabricated for potentiometric sensors to proceed with dynamic measurement and real-time display. This whole measurement system can be classified with two parts, which are the sensing electrode and measurement system. The sensing electrode is RuO 2 /PET structure and the real-time motoring system uses the LabVIEW software to accomplish. Real-time motoring system was used to detect the pH value of solution. Measurement results can show many functions such as real-time monitoring system, data search system, data statistics system, data upload, data download, and web publishing. In addition, the file size of proposed real-time motoring system is only 437 Kbyte.

Changes in an athlete's physiological and health metabolic profiles after detraining have not been studied in elite Taekwondo (TKD) athletes. To enable a better understanding of these physiological changes to training cessation, this study examined the effects of 8-weeks detraining on the aerobic capacity, body composition, inflammatory status and health metabolic profile in elite TKD athletes. Sixteen elite TKD athletes (age: 21.0 ± 0.8 yrs, BMI: 22.4 ± 3.9 kg/m2; Mean ± SD; 11 males and 5 females) participated in this study. Physical activity level assessment using computerized physical activity logs was performed during the competitive preparation season (i.e. one-week before national competition) and at two week intervals throughout the detraining period. Participant aerobic capacity, body fat, and blood biomarkers were measured before and after detraining, and the blood biomarker analyses included leukocyte subpopulations, blood glucose, insulin, dehydroepiandrosterone-sulfate (DHEA-S), and cortisol. Eight-week detraining increased DHEA-S/cortisol ratio (+57.3%, p = 0.004), increased insulin/cortisol ratio (+59.9%, p = 0.004), reduced aerobic power (-2.43%, p = 0.043), increased body fat accumulation (body fat%: +21.3%, p < 0.001), decreased muscle mass (muscle mass%: -4.04%, p < 0.001), and elevated HOMA-IR (the biomarker of systemic insulin resistance; +34.2%, p = 0.006). The neutrophil-to-lymphocyte ratio (NLR), a systemic inflammatory index, increased by 48.2% (p = 0.005). The change in aerobic capacity was correlated with the increased fat mass (r = -0.429, p = 0.049) but not with muscle loss. An increase in the NLR was correlated to the changes in HOMA-IR (r = 0.44, p = 0.044) and aerobic capacity (r = -0.439, p = 0.045). We demonstrate that 8-week detraining suppresses physiological stress but rapidly results in declines in athletic performance and health metabolic profiles, including reduced aerobic capacity, increased body fat, muscle loss, insulin resistance development and elevated systemic inflammatory status in these young elite TKD athletes. The inflammation state was positively associated with insulin resistance development, fat mass, WHR (the index for central fat accumulation), and the decline in VO2max.

In this paper, the pH sensor and glucose biosensor were integrated with microfluidic framework, and the sensing characteristics under the dynamic conditions, i.e., solution under flowing condition, were investigated. The indium-gallium–zinc oxide (IGZO), as a sensing membrane, was deposited on aluminum electrodes/polyethylene terephthalate substrate. Then, the screen-printed technology was used to accomplish the encapsulation of sensor. The glucose biosensor based on enzyme needed an extra glucose sensing membrane, which was composed of glucose oxidase (GO x ) and nafion. The glucose sensing membrane was dropped on the IGZO/Al sensing membrane. According to the experimental results, the optimal sensing characteristics of pH sensor and glucose biosensor under the dynamic conditions were better than those under the static condition (solution without flowing). The optimal average sensitivity and linearity were 56.857 mV/pH and 0.997 at $25~\mu \text{L}$ /min flow rate, respectively (in pH sensor), and 7.255 mV/mM and 0.994 at $20~\mu \text{L}$ /min flow rate, respectively (in glucose biosensor). Furthermore, the hysteresis effect and drift effect were researched for pH sensor, and the electrochemical impedance spectroscopy was used to demonstrate whether the IGZO/Al sensing membrane had been modified by GO x and nafion and it was found that the additions of GO x and nafion had increased the electron transfer resistance ( $\text{R}_{\mathrm {et}})$ .

The purpose of this study was to investigate whether an amino acid mixture increases glucose uptake across perfused rodent hindlimb muscle in the presence and absence of a submaximal insulin concentration, and if the increase in glucose uptake is related to an increase in GLUT4 plasma membrane density. Sprague-Dawley rats were separated into one of four treatment groups: basal, amino acid mixture, submaximal insulin, or amino acid mixture with submaximal insulin. Glucose uptake was greater for both insulin-stimulated treatments compared with the non-insulin-stimulated treatment groups but amino acids only increased glucose uptake in the presence of insulin. Phosphatidylinositol 3-kinase (PI 3-kinase) activity was greater for both insulin-stimulated treatments with amino acids having no additional impact. Akt substrate of 160 kDa (AS160) phosphorylation, however, was increased by the amino acids in the presence of insulin, but not in the absence of insulin. AMPK was unaffected by insulin or amino acids. Plasma membrane GLUT4 protein concentration was greater in the rats treated with insulin compared with no insulin in the perfusate. In the presence of insulin, amino acids increased GLUT4 density in the plasma membrane but had no effect in the absence of insulin. AS160 phosphorylation and plasma membrane GLUT4 density accounted for 76% of the variability in muscle glucose uptake. Collectively, these findings suggest that the beneficial effects of an amino acid mixture on skeletal muscle glucose uptake, in the presence of a submaximal insulin concentration, are due to an increase in AS160 phosphorylation and plasma membrane-associated GLUT4, but independent of PI 3-kinase and AMPK activation.

Amyloids are pathogenic hallmarks in many neurodegenerative diseases such as amyloid-β (Aβ) fibrils in Alzheimer's disease (AD). Here, the effect of gold nanoparticles (AuNPs) on amyloids is examined using Aβ as a model system. It is found that bare AuNPs inhibited Aβ fibrillization to form fragmented fibrils and spherical oligomers. Adding bare AuNPs to preformed Aβ fibrils results in ragged species where AuNPs bind preferentially to fibrils. Similar results are demonstrated with carboxyl- but not amine-conjugated AuNPs. Co-incubation of negatively charged AuNPs with Aβ relieved Aβ toxicity to neuroblastoma. Overall, it is demonstrated that AuNPs possessing negative surface potential serve as nano-chaperones to inhibit and redirect Aβ fibrillization, which could contribute to applications for AD.

In this paper, an instantaneous maximum power point tracking (MPPT) control is first adopted to achieve fast tracking response for the photovoltaic (PV) power generation system. Then an instantaneous real power tracking control is proposed to overcome the dilemma of the inherent double line frequency ripple without adding an additional circuit so that one can replace the large electrolytic capacitor with small bipolar film-type capacitors to achieve longer lifetime of the single-phase grid-tied inverter. Furthermore, the mathematical model of the PV system is derived and the minimum capacitance for a specified allowable DC-link capacitor voltage swing is obtained. Finally, simulation results are given for verifying the feasibility of the proposed control strategy.

In this paper, a novel circulating current control scheme of paralleled single-phase boost-type full-bridge converters is proposed. The novel circulating current control scheme doesn't require any communication between paralleled converters. Simultaneously, the proposed circulating current control scheme improves the performance of the parallel system and reduces the circulating currents which result from the parallel connection. Based on this control scheme, not only input current shaping of each converter is improved, but also current sharing among paralleled converters is achieved. Both simulation and experimental results verified the validity of the proposed circulating current control scheme.

The objective of this paper is focused on developing an improved current-fed converter with new voltage multiplier circuit for low-voltage distributed energy systems. The proposed four-phase current-fed converter is with interleaved configuration and preserving the inherent advantage with smaller input current ripple. Through the proposed topology, the high voltage gain can be achieved using the relatively lower transformer turns ratio. Also, the voltage stresses of both active switches and diodes are greatly reduced so that the low on-resistance switches can be adopted and the reverse-recovery effect of diodes can be decreased naturally. The DC and AC small signal models of the proposed converter are derived for better closed loop control, and some design guidelines are then given for circuit implementation. Both simulation and experimental results indeed verify the effectiveness of the proposed converter.

The main goal of this study was to investigate the long-term effect of daily 8-hour mild intermittent hypoxia (14-15% O2) on glucose tolerance and muscle morphology of Sprague-Dawley rats. The involvement of AMPK-PGC-1alpha-VEGF signaling pathways in the skeletal muscle was also determined during the first 8 hours of hypoxia. We found that mRNA levels of VEGF and PGC-1alpha were significantly increased above control after 8-h mild hypoxia without a change in AMPK phosphorylation. After 8 weeks of mild intermittent hypoxia treatment, plasma glucose and insulin levels in oral glucose tolerance test (OGTT), epididymal fat mass, and body weight were significantly lower compared to the control group. While soleus muscle weight was not changed, capillary and fiber densities in the hypoxia group were 33% and 35% above the control suggesting reorganization of muscle fibers. In conclusion, our data provide strong evidence that long-term mild intermittent hypoxia decreases the diffusion distance of glucose and insulin across muscle fibers, and decreases adiposity in rats. These changes may account for the improved glucose tolerance observed following the 8-week hypoxia treatment, and provides grounds for investigating the development of a mild non-pharmacological intervention in the treatment of obesity and type 2 diabetes.

This study aimed to determine the role of DHEA-S in coping against the exercise training mixing aerobic and resistance components. During 5-day successive exercise training, 16 young male participants (19.2 ± 1.2 years) received either a placebo (flour capsule) or DHEA (100 mg/day) in a double-blinded and placebo-controlled design. Oral DHEA supplementation significantly increased circulating DHEA-S by 2.5-fold, but a protracted drop (~35 %) was observed from Day 3 during training. In the Placebo group, only a minimal DHEA-S reduction (~17 %) was observed. Changes in testosterone followed a similar pattern as DHEA-S. Muscle soreness was elevated significantly on Day 2 for both groups to a similar extent. Lower muscle soreness was observed in the DHEA-supplemented group on Day 3 and Day 6. In the Placebo group, training increased circulating creatine kinase (CK) levels by approximately ninefold, while only a threefold increase was observed in the DHEA-supplemented group. This mix-type exercise training improved glucose tolerance in both groups, while lowering the insulin response to the glucose challenge, but no difference between treatments was observed. Our results suggest that DHEA-S may play a role in protecting skeletal muscle from exercise training-induced muscle damage.

In this paper, a family of single-stage single-switch photovoltaic (PV) module integrated converters (MICs) with steep voltage conversion gain capability and galvanic isolation is presented. As an illustration, the new MIC topology based on the isolated-type single-ended primary-inductor converter (Sepic) with coupled inductor is analyzed and developed. Moreover, a fast maximum power point tracking (MPPT) strategy with linear current control is adapted in the proposed SEPIC-type PV MIC. Finally, a speciation of single-phase 150W prototype is constructed, and experimental results indeed verify the effectiveness of the proposed converter.

The objective of this paper is to construct a novel transformerless five-level multistring inverter topology for fuel-cell microgrid system. In this study, a high step-up converter is introduced as a front-end stage to improve the conversion efficiency of conventional boost converters and to stabilize the output DC voltage of various DERs such as PV and fuel cell modules for use with the simplified multilevel inverter. The simplified multilevel inverter requires only six active switches instead of the eight required in the conventional H-bridge cascaded multilevel inverter. In addition, two active switches are operated under line frequency. The presented multistring inverter offers strong advantages such as improved output waveforms, smaller filter size, and lower EMI and THD. Experimental results show the effectiveness of the proposed solution.

Protein and certain amino acids (AA) have been found to lower blood glucose. Although these glucose-lowering AA are important modulators of skeletal muscle metabolism, their impact on muscle glucose uptake remains unclear. We therefore examined how an AA mixture consisting of 2 mM isoleucine, 0.012 mM cysteine, 0.006 mM methionine, 0.0016 mM valine, and 0.014 mM leucine impacts skeletal muscle glucose uptake in the absence or presence of a submaximal (sINS) or maximal insulin (mINS) concentration. The AA mixture, sINS, and mINS significantly increased 2-[3H]deoxyglucose (2-DG) uptake by 63, 79, and 298% above basal, respectively. When the AA mixture was combined with sINS and mINS, 2-DG uptake was further increased significantly by 26% ( P = 0.028) and 14% ( P = 0.032), respectively. Western blotting analysis revealed that the AA mixture increased basal and sINS Akt substrate of 160 kDa (AS160) phosphorylation, while AA mixture did not change phosphorylation of Akt or mammalian target of rapamycin (mTOR) under these conditions. Interestingly, addition of the AA mixture to mINS increased phosphorylation of mTOR, Akt as well as AS160, compared with mINS alone. These data suggest that certain AA increase glucose uptake in the absence of insulin and augment insulin-stimulated glucose uptake in an additive manner. Furthermore, these effects appear to be mediated via a pathway that is independent from the canonical insulin cascade and therefore may prove effective as an alternative therapeutic treatment for insulin resistance.

The aims of this investigation were to evaluate the effect of an amino acid supplement on the glucose response to an oral glucose challenge ( experiment 1) and to evaluate whether differences in blood glucose response were associated with increased skeletal muscle glucose uptake ( experimental 2). Experiment 1 rats were gavaged with either glucose (CHO), glucose plus an amino acid mixture (CHO-AA-1), glucose plus an amino acid mixture with increased leucine concentration (CHO-AA-2), or water (PLA). CHO-AA-1 and CHO-AA-2 had reduced blood glucose responses compared with CHO, with no difference in insulin among these treatments. Experiment 2 rats were gavaged with either CHO or CHO-AA-1. Fifteen minutes after gavage, a bolus containing 2-[3H]deoxyglucose and [U-14C]mannitol was infused via a tail vein. Blood glucose was significantly lower in CHO-AA-1 than in CHO, whereas insulin responses were similar. Muscle glucose uptake was higher in CHO-AA-1 compared with CHO in both fast-twitch red (8.36 ± 1.3 vs. 5.27 ± 0.7 μmol·g−1·h−1) and white muscle (1.85 ± 0.3 vs. 1.11 ± 0.2 μmol·g−1·h−1). There was no difference in Akt/PKB phosphorylation between treatment groups; however, the amino acid treatment resulted in increased AS160 phosphorylation in both muscle fiber types. Glycogen synthase phosphorylation was reduced in fast-twitch red muscle of CHO-AA-1 compared with CHO, whereas mTOR phosphorylation was increased. These differences were not noted in fast-twitch white muscle. These findings suggest that amino acid supplementation can improve glucose tolerance by increasing skeletal muscle glucose uptake and intracellular disposal through enhanced intracellular signaling.

Abnormally high concentrations of Zn(2+), Cu(2+), and Fe(3+) are present along with amyloid-β (Aβ) in the senile plaques in Alzheimer disease, where Al(3+) is also detected. Aβ aggregation is the key pathogenic event in Alzheimer disease, where Aβ oligomers are the major culprits. The fundamental mechanism of these metal ions on Aβ remains elusive. Here, we employ 4,4'-Bis(1-anilinonaphthalene 8-sulfonate) and tyrosine fluorescence, CD, stopped flow fluorescence, guanidine hydrochloride denaturation, and photo-induced cross-linking to elucidate the effect of Zn(2+), Cu(2+), Fe(3+), and Al(3+) on Aβ at the early stage of the aggregation. Furthermore, thioflavin T assay, dot blotting, and transmission electron microscopy are utilized to examine Aβ aggregation. Our results show that Al(3+) and Zn(2+), but not Cu(2+) and Fe(3+), induce larger hydrophobic exposures of Aβ conformation, resulting in its significant destabilization at the early stage. The metal ion binding induces Aβ conformational changes with micromolar binding affinities and millisecond binding kinetics. Cu(2+) and Zn(2+) induce similar assembly of transiently appearing Aβ oligomers at the early state. During the aggregation, we found that Zn(2+) exclusively promotes the annular protofibril formation without undergoing a nucleation process, whereas Cu(2+) and Fe(3+) inhibit fibril formation by prolonging the nucleation phases. Al(3+) also inhibits fibril formation; however, the annular oligomers co-exist in the aggregation pathway. In conclusion, Zn(2+), Cu(2+), Fe(3+), and Al(3+) adopt distinct folding and aggregation mechanisms to affect Aβ, where Aβ destabilization promotes annular protofibril formation. Our study facilitates the understanding of annular Aβ oligomer formation upon metal ion binding.

In this paper, a robust field-weakening control strategy for IPMSM drives is proposed to achieve fast response and minimum copper loss. First, the classification of three operation regions for positive speed operation is adopted. It is seen that current limit and voltage limit will affect the maximum torque capability and minimum copper loss operation. Second, in order to achieve minimum copper loss as well as fast response, the proposed robust controller adjust the d-axis current command and the upper bounds of the maximum q-axis current of the speed controller through an integral controller of the error between the maximum inverter output voltage and the output voltage command resulting from the current controllers. Finally a DSP-based prototype drive is constructed and some experimental results are given to verify the validity of the proposed strategy.

This paper presents an integration of the interleaved bi-directional DC/DC converter with a vector controlled permanent magnet synchronous motor (PMSM) drive to give the motor operating in high speed with minimum copper loss control. The interleaved DC/DC converter is designed in the discontinuous conduction mode (DCM) such that the controller design becomes straightforward. The large signal perturbation usually makes the controller saturation and the inductor over current. Hence, the anti-windup and current limit considerations are also discussed in the paper. The modified vector controlled scheme of the PMSM drive is developed by considering dynamic DC link voltage boosting such that the motor can always have minimum copper loss performance in high speed. Finally, several experimental results are provided to show the performances of the integrated drive.

Background This study compared the effects of ingesting cereal and nonfat milk (Cereal) and a carbohydrate-electrolyte sports drink (Drink) immediately following endurance exercise on muscle glycogen synthesis and the phosphorylation state of proteins controlling protein synthesis: Akt, mTOR, rpS6 and eIF4E. Methods Trained cyclists or triathletes (8 male: 28.0 ± 1.6 yrs, 1.8 ± 0.0 m, 75.4 ± 3.2 kg, 61.0 ± 1.6 ml O2•kg-1•min-1; 4 female: 25.3 ± 1.7 yrs, 1.7 ± 0.0 m, 66.9 ± 4.6 kg, 46.4 ± 1.2 mlO2•kg-1•min-1) completed two randomly-ordered trials serving as their own controls. After 2 hours of cycling at 60–65% VO2MAX, a biopsy from the vastus lateralis was obtained (Post0), then subjects consumed either Drink (78.5 g carbohydrate) or Cereal (77 g carbohydrate, 19.5 g protein and 2.7 g fat). Blood was drawn before and at the end of exercise, and at 15, 30 and 60 minutes after treatment. A second biopsy was taken 60 minutes after supplementation (Post60). Differences within and between treatments were tested using repeated measures ANOVA. Results At Post60, blood glucose was similar between treatments (Drink 6.1 ± 0.3, Cereal 5.6 ± 0.2 mmol/L, p < .05), but after Cereal, plasma insulin was significantly higher (Drink 123.1 ± 11.8, Cereal 191.0 ± 12.3 pmol/L, p < .05), and plasma lactate significantly lower (Drink 1.4 ± 0.1, Cereal 1.00 ± 0.1 mmol/L, p < .05). Except for higher phosphorylation of mTOR after Cereal, glycogen and muscle proteins were not statistically different between treatments. Significant Post0 to Post60 changes occurred in glycogen (Drink 52.4 ± 7.0 to 58.6 ± 6.9, Cereal 58.7 ± 9.6 to 66.0 ± 10.0 μmol/g, p < .05) and rpS6 (Drink 17.9 ± 2.5 to 35.2 ± 4.9, Cereal 18.6 ± 2.2 to 35.4 ± 4.4 %Std, p < .05) for each treatment, but only Cereal significantly affected glycogen synthase (Drink 66.6 ± 6.9 to 64.9 ± 6.9, Cereal 61.1 ± 8.0 to 54.2 ± 7.2%Std, p < .05), Akt (Drink 57.9 ± 3.2 to 55.7 ± 3.1, Cereal 53.2 ± 4.1 to 60.5 ± 3.7 %Std, p < .05) and mTOR (Drink 28.7 ± 4.4 to 35.4 ± 4.5, Cereal 23.0 ± 3.1 to 42.2 ± 2.5 %Std, p < .05). eIF4E was unchanged after both treatments. Conclusion These results suggest that Cereal is as good as a commercially-available sports drink in initiating post-exercise muscle recovery.

Voltage unbalance in a three-phase system causes double line frequency ripples in the dc link. In this paper, an instantaneous power method is adopted to analysis PWM converter under unbalanced condition. Based on this method, a lossless concept is proposed to reduce the double line voltage ripples in the dc link. Instead of using the conventional control strategy, the coupled energy of line impedance from positive and negative sequences which affect the output voltage is considered. Then, based on a lossless concept, a current control method is presented. Finally, simulation results are given to illustrate the significance of the proposed lossless concept and as a verification of the validity of the derived control scheme.

In this paper, the generating mechanism of circulating currents for grid-connected parallel three-phase inverters is first explored. Then, a new and practical definition of circulating currents for each phase and each converter is proposed. Third, a mathematical model of the circulating current is then derived by using the well-known state space averaging technique. Finally, some simulation results obtained from the proposed model are compared with that by definition to verify the validity of the proposed model.

A growing demand for size reduction of power systems has stimulated substantial development and research efforts in high power density power supplies. To achieve high power density converters, it is required that they operate at high switching frequencies. This paper presents a high frequency resonant AC power supply with frequency tracking control by using phase-locked loop (PLL) techniques. Based on the PLL control method, the resonant inverter can be guaranteed to provide a stable operation characteristic in spite of sensitive load parameters variation as well as power regulation. The detailed control circuit and the operation principle of resonant AC power supply are analyzed and verified experimentally.

In this paper, a general definition of circulating currents for each phase of each paralleled converter with different rating is first proposed. Then, based on this definition, the corresponding circulating current index, gammakj , and unbalance rate, beta j , for paralleled converter j are proposed to provide one with a quantitative measure about the serious status of the circulating current just like the commonly used total harmonic distortion (THD) factor. Third, the corresponding general model of circulating currents is also derived for understanding the governing dynamic behavior of circulating currents. Finally, some examples are also given to illustrate the significance of the proposed indices and as a verification of the validity of the derived general model.

In this study, the electrochromic thin film of tungsten oxide $({\hbox{WO}}_{1-x})$ was electrodeposited on indium tin oxide/glass (ITO/Glass) by potentiostatic method. The electrochemical characteristic and optical characteristic were analyzed by different deposition time, and the electrochromic behaviors of the ${\hbox{WO}}_{1-x}/{\hbox{ITO}}/{\hbox{Glass}}$ were performed in a 0.1 M lithium perchlorate/propylene carbonate (LiClO $_{4}$ /PC) electrolyte. The deposition time of ${\hbox{WO}}_{1-x}$ thin film was set at 1200 seconds, which optimal transmittance variation $(\Delta{\rm T}\hbox{\%})$ , and coloration efficiency $(\eta)$ were 73.2% and 53.4 cm $^{2}$ /C, respectively.

The present study determined the interactive effect of an acute bout of resistance exercise and dehydroepiandrosterone (DHEA) administration on glucose tolerance and serum lipids. Twenty middle-aged female subjects performed an acute bout of resistance exercise and were subsequently divided into two groups: placebo (age 40.7 +/- 2.0) and DHEA administered (age 39.0 +/- 2.7). Ten subjects who received DHEA (age 41.5 +/- 4.6) participated in a non-exercise control. DHEA (25 mg twice daily) or placebo was orally supplemented for 48 hours. Before exercise and 48 hours after the last exercise bout (14 hours after the last DHEA intake), an oral glucose tolerance test and an insulin concentration were determined. Levels of fasting serum cholesterol and triglyceride, tumor necrosis factor-alpha (TNF-alpha), creatine kinase (CK) were also measured. The DHEA administration significantly elevated the fasting dehydroepiandrosterone sulfate (DHEA-S) level by approximately 3-fold. Both acute resistance exercise and DHEA administration improved glucose tolerance, but no addictive effect was found. Furthermore, exercise and DHEA administration did not affect serum triglyceride and cholesterol levels, but both lipids were significantly lowered when DHEA was given following exercise. Resistance exercise induced elevations in serum CK and TNFalpha levels, but these increases were attenuated by the DHEA administration. The new finding of this study was that post-exercise DHEA administration decreased serum triglycerides and cholesterol. This effect appeared to be associated with its TNF-alpha lowering action.