Charge storage mechanisms of electrodeposited MnO
2 in various aprotic ionic liquids (ILs) are studied using in situ X-ray absorption spectroscopy (XAS). The analytical results show that a unique ...thiocyanate (SCN
−) anion can reversibly insert/desert into/from the tunnels between the MnO
6 octahedral subunits depending on the applied potential. This process charge compensates the Mn
3+/Mn
4+ redox transition upon charging–discharging and thus contributes to an ideal pseudocapacitive behavior of the MnO
2 electrode. The present work would open up a route for developing a novel oxide-based supercapacitor, with high cell-voltage, high thermal stability, and high safety, incorporating IL electrolytes.
Although angiotensin receptor antagonists and 3-hydroxy-3-methylgultaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) have been shown to attenuate proteinuria individually, it remains unclear ...whether proteinuria may be additionally improved by statin therapy in well-controlled hypertensive patients treated with angiotensin receptor antagonists-based regimen and whether withdrawal of chronic statin treatment may abrogate this beneficial effect in normolipidemic patients.
A total of consecutive 82 proteinuric patients treated with antihypertensive agents, including losartan, were randomized 10 mg of pravastatin or placebo with a 6-month treatment. After completing 6 months of drug treatment, the pravastatin-treated patients were randomly assigned to continue (N= 19) or withdraw (N= 17) pravastatin for a further 6 months.
Subjects treated with pravastatin had significant further improvement of proteinuria at 6 months compared with placebo group (559 +/- 251 mg/24 hours vs. 1262 +/- 557 mg/24 hours) (P < 0.0001). Of 17 patients assigned to withdraw pravastatin, proteinuria returned to the pretreatment levels and was significantly higher than those who continued treatment. Multivariate analysis revealed that proteinuric improvement was significantly correlated with the continuous statin use. Urinary excretion of endothelin-1 (ET-1) is decreased in pravastatin-treated patients, but withdrawal of statin resulted in 27% up-regulation. The linear regression models in the initial statin-treated group showed that changes in urinary ET-1 correlated with urinary protein excretion (r= 0.83, P < 0.0001).
We conclude that pravastatin administration is associated with improved proteinuria probably by inhibiting urine ET-1 levels in patients with losartan-based treatment. However, statin withdrawal abrogates this beneficial effect in patients initially responsive to this therapy.
A rising forming voltage issue with scaling‐down resistive random access memory (RRAM) device cells is successfully solved by introducing new high‐permittivity (high‐k) material as the side‐wall ...spacer structure. As reported by Ting‐Chang Chang, Kuan‐Chang Chang, and co‐workers in article number 1700171, both COMSOL‐simulated electrical field and electrical measurements confirm the confined the electrical field by the surrounded high‐k spacer. The cross section views clearly show the different structures with a spacer.
This paper focuses on digital signal processor based technique to achieve a grid-connected photovoltaic power generation system with single-stage controlled algorithm. The researched system is ...consists of a full-bridge high-frequency DC/DC converter with the proposed symmetric phase-shift modulation to achieve the ZVS switching function, and a DC/AC inverter which can have two operating methods depending on the applied situation, respectively, for the two-stage DC-AC inverter and a single-stage DC-AC inverter. It replaces the traditional two stages of independently control algorithms with the integrated single-stage control to obtain high conversion efficiency. Finally, a prototype of 350W system with the maximum power point function is settled to verify the proposed idea.
Intrinsic unipolar SiOx-based Resistive-RAM (ReRAM) characteristics have been investigated. The cross-bar MIM structures have been examined under AC frequency response, by varying device area, ...temperature and current states. The results provide additional insights into the hopping/switching mechanisms. For the first time, by using SiOx/HfOx stacking engineering, we have developed a low-voltage operation (<; 2V) for SiOx-based ReRAM. The SiOx/HfOx stacking optimization not only maintains the RS behaviors even in air environment without any programming window degradation, but also further reduces the switching voltage below 2V.
Incorporation of nitrogen as an oxygen-confining layer in the resistance switching reaction region is investigated to improve the reliability of resistance random access memory (RRAM). The switching ...mechanism can be attributed to the formation and rupture of conduction filaments. A compatible WSiON (around 5 nm) layer is introduced at the interface of tungsten silicon oxide (WSiO x ) and TiN electrode to prevent the randomly diffusing oxygen ions surpassing the storage region of the WSiON layer. The double-layer WSiO x /WSiON memory structure would enhance the endurance over 100 times so as to better confirm the WSiO x RRAM application of nonvolatile memory.
The effects of age on dopamine (DA) release in the nucleus accumbens (NAc) and on amphetamine (AMPH)-induced locomotor activity were studied by microdialysis in freely-moving young (5 month) and old ...(24 month) rats. Both basal extracellular DA and 3,4-dihydroxyphenylacetic acid (DOPAC) release and that following intra-accumbens perfusion of AMPH (1–10 μM) were significantly lower in old rats. After intraperitoneal injection of AMPH (1.5 mg/kg), no age-related change in DA release was seen in the NAc, but locomotor activity was found to increase much more in young rats than in old ones. These results indicate that (1) old rats show decreased extracellular DA and DOPAC release, both in the basal state and following intra-accumbens infusion of AMPH, and (2) the age-related locomotor activity induced by systemic injection of AMPH is not paralleled by changes in DA release in the NAc.
Background: Aortic valve replacement relieves mechanical outflow obstruction in patients with aortic stenosis. However, there is limited information on whether aortic valve replacement can provide ...regression of ventricular repolarisation inhomogeneity.
Objectives: To determine whether aortic valve replacement can provide regression of ventricular repolarisation inhomogeneity in patients with aortic stenosis after bileaflet aortic valve replacement.
Methods: We studied the changes of electrocardiographic QT or QTc intervals and QT or QTc dispersions of 71 patients with severe aortic stenosis and angiographically insignificant coronary lesions (<50% in diameter) before and after valve replacement (6±3 days after operation). Seventy-one healthy control subjects, matched for age and sex, served as control subjects. Twelve-lead electrocardiograms and echocardiographic examinations were measured before and after surgery. The QT interval was corrected for heart rate using the standard Bazett formula. QT dispersion was defined as the difference between maximal and minimal QT interval measurements occurring among any of the 12 leads on a standard electrocardiogram. QTc dispersion was calculated in a manner similar to QT dispersion. No subject had fewer than nine measurable leads.
Results: Left ventricular systolic blood pressure, pressure gradient across aortic valve, left ventricular mass index, and systolic wall stress were significantly reduced after valve replacement compared with before valve replacement. The QT interval significantly decreased from 425±38 ms to 398±32 ms after replacement (
P<0.0001). The QTc dispersion significantly decreased from 62±25 ms to 32±13 ms after replacement (
P<0.0001). The value of QT or QTc dispersion after replacement was similar to that in controls. Univariate analysis revealed that QTc dispersion was significantly only correlated with left ventricular mass index (
r=0.236,
P=0.05). Multivariate analysis revealed that the best predictor of QTc dispersion was sex and left ventricular mass index (
P=0.008 and 0.005, respectively).
Conclusions: Our study demonstrated a favorable consequence of aortic valve replacement distinct from hemodynamic improvement. Patients with aortic stenosis before valve replacement have abnormal prolonged QT or QTc intervals and increased QT or QTc dispersions. After successful valve replacement left ventricular mass index regressed and QT or QTc intervals and QT or QTc dispersions were normalized. These findings warrant further investigation in a large trial and long-term follow-up for clinical implications.
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