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Control valve stiction is prevalent in the process industry, leading to oscillations in process variables and degrading unit performance. Stiction is usually repaired during scheduled plant maintenance, but until then, compensation methods are required to reduce oscillations. This study presents a novel approach to address this problem by identifying control valve and process models and optimizing control parameters. The method combines a stiction model, a process model, and a controller to achieve optimal control with stiction. Additionally, the method incorporates a controller output filter and considers undershooting during the step response for control performance assessment. The proposed method is designed to handle different types of valve stiction models, providing a versatile solution. The results show that our method significantly improves the control loop performance of all valves tested.

Cesium lead bromide (CsPbBr3) nanocrystals (NCs) with nanoplatelet shapes and different crystal structures were synthesized via the ligand-assisted reprecipitation (LARP) method using different pairs of ligands and antisolvents, namely oleic acid (OA) or linoleic acid (LA) as the ligand and toluene or chloroform as the antisolvent. The XRD data revealed that the obtained CsPbBr3 NCs have different crystal structures, namely orthorhombic, tetragonal, and cubic, depending on the ligand and antisolvent pair, which exhibited significantly different photoluminescence (PL) characteristics. From the XPS data, these CsPbBr3 nanoplatelets showed two doublet peaks of the Br-3d orbital at different binding energies, representing two different chemical environments of the Br bonds. The doublet peak apparent at a higher binding energy was associated with the Br chemical states at the crystal surface, which appeared because of the distorted crystal structure resulting from the interaction of the solvent and ligand with Br ions. The PL emission consists of three luminescence centers: a PL band peaked at 520 nm (A band), a PL band peaked at 540 nm (B band), and a PL band tail, which can be discussed in terms of exciton models. Stable and intense luminescence was observed in CsPbBr3 nanoplatelets synthesized using a pair of toluene antisolvent and LA ligand, namely CsPbBr3#(Tl/LA). The orthorhombic crystal structure and distorted crystal surface in this sample may lead to confinement of the photogenerated small exciton-polaron and weak phonon interactions, which effectively hinder exciton dissociation, particularly at the crystal surface, resulting in intense PL. The results of this study may provide additional important insights into the role of the antisolvent and ligand in the formation of CsPbBr3 NCs and the exciton behavior in their PL characteristics, which may also be found in other types of halide perovskites.

Background: The association of body mass index (BMI) and an "obesity paradox" with cardiovascular risk prediction is controversial. This study aimed to evaluate the impact of elevated BMI on the outcome of transcatheter aortic valve replacement (TAVR) for aortic stenosis. Methods: This retrospective study included 1019 patients with a BMI of ≥18.5 kg/m² divided into 3 groups: 1) normal BMI (18.5-24.9 kg/m²), 2) overweight (25-29.9 kg/m²), and 3) obese (≥30 kg/m²). Propensity score matching was used to compare normal BMI with overweight and normal BMI with obese. Results: The median age of the cohort was 82 years, and 348 patients had a normal BMI, while 319 and 352 patients were overweight and obese, respectively. After 1 : 1 propensity score matching, 258 and 192 pairs between normal BMI and overweight, and normal BMI and obese patients, respectively, were analyzed. Both overweight and obese patients had higher post-transaortic mean gradients and lower indexed effective orifice areas compared to normal BMI patients. During a median follow-up of 25 (range: 0.1-72) months, all-cause mortality was similar between overweight or obese patients and patients with a normal BMI. However, in a subgroup analysis of patients with moderate/severe chronic lung disease, all-cause mortality was significantly higher in obese patients compared with normal BMI patients (hazard ratio = 3.49, 95% confidence interval, 1.21-10.0, P = .021). Conclusions: In this study, the "obesity paradox" was not observed in patients undergoing TAVR; rather, in patients with significant lung disease, obesity may be associated with worse mid-term outcomes after TAVR. [ABSTRACT FROM AUTHOR]

We report a case of an open surgery for acute aortic dissection involving the right aortic arch with an aberrant left subclavian artery, a Kommerell diverticulum, and a descending aortic aneurysm. We judged that stent grafting was anatomically unsuitable and performed graft replacement via right thoracotomy. Although in situ reconstruction of the aberrant subclavian artery was not achieved owing to the vulnerability of the dissected vessel wall, the patient recovered without associated ischemic symptoms. Graft replacement via lateral thoracotomy remains an important option for acute aortic dissection involving an aberrant subclavian artery and a Kommerell diverticulum. However, an optimal strategy that considers the reconstruction of the aberrant subclavian artery is required.

This postmarketing surveillance study was conducted to evaluate the safety and effectiveness of onabotulinumtoxinA in Japanese patients with laryngeal dystonia (LD). Patients receiving onabotulinumtoxinA for the first time were enrolled and observed for up to 12 months following the first injection. Safety assessment included adverse drug reactions (ADRs), and effectiveness assessments included the Voice Handicap Index-10 (VHI-10) and physician’s global assessment (PGA). ADRs were observed in 48 (5.8%) of 834 patients in the safety analysis set, including dysphonia in 43 (5.2%) patients and dysphagia in 7 (0.8%) patients. The change in total VHI-10 score (mean) in 790 patients included in the effectiveness analysis set showed that improvement in adductor LD peaked at 2 months after the first injection, while patients with abductor or mixed LD showed a gradual attenuation of effect 2–4 weeks post-injection. The change in total VHI-10 score in subsequent injections was generally similar to that following the first injection. The overall effectiveness rate according to the PGA was 93.4% (738/790 patients). The results demonstrate that onabotulinumtoxinA is a well-tolerated and effective treatment for LD in real-world clinical practice.

Abstract Background Transcatheter aortic valve replacement (TAVR) is a minimally invasive approach to aortic valve replacement. However, critical cardiovascular collapse can occur during the procedure for various reasons. Case presentation A 90-year-old man with severe aortic stenosis and left circumflex artery stenosis developed acute torrential mitral regurgitation (MR) during TAVR. The valve deployment process induced left ventricular dyssynchrony due to left bundle-branch block and myocardial ischemia in the left circumflex artery region with torrential MR. Transesophageal echocardiography clearly demonstrated the mechanisms of MR, which was successfully bailed out by left ventricular pacing and intra-aortic balloon pumping. Conclusions MR can be seriously exaggerated by various and complicated mechanisms during TAVR and should be rapidly assessed and appropriately managed depending on its mechanisms.

We have investigated the relationship between the electrical properties and interfacial atomic structure of SiO2/4H-SiC interfaces, prepared by dry and wet thermal oxidation procedures with 4H-SiC (0001) and 4H-SiC (000-1) substrates, using extended x-ray absorption fine structure (EXAFS) spectroscopy and electrical methods. From the current–voltage (I–V) and capacitance–voltage (C–V) measurements, the gate leakage current onset and density of interface states were shown to depend on the thermal oxidation procedure used for creating SiO2/4H-SiC (000-1) interfaces. This dependence was not observed for SiO2/4H-SiC (0001) interfaces. From EXAFS oscillations, we found that C and Si vacancies formed at the SiC side of SiO2/4H-SiC (0001) and SiO2/4H-SiC (000-1) interfaces, respectively. Compressive stress at the SiC sides of SiO2/4H-SiC (0001) and SiO2/4H-SiC (000-1) interfaces prepared with the dry thermal oxidation procedure caused decreases in bond lengths. Stress at the interface was smaller in the case of wet oxidation. Wet oxidation released the interface stress more effectively for 4H-SiC (000-1) substrates than for 4H-SiC (0001) substrates. A high gate leakage current onset related to a high interface charge, while a high density of interface states related to a high interface stress and a high interface roughness.

We investigated the relationship between the band-offset, the gate leakage current, and the interface states density on SiO2/4H-SiC (000-1) structures via hard x-ray photoelectron spectroscopy and electrical measurements. From the observed band-offset, we found that conduction band offset (ΔEc) depended on the oxidation procedure, but valence band-offset (ΔEv) did not. In addition, ΔEv was larger than ΔEc, indicating that electron tunneling was more predominant than hole tunneling. SiO2 prepared by a dry oxidation procedure exhibited the highest gate leakage current onset and the highest interface states density and the largest ΔEc, whereas a wet oxidation procedure produced the lowest gate leakage current onset, the lowest interface states density, and the smallest ΔEc. Oxygen annealing after wet oxidation effectively increased gate leakage current onset, which increased the interface states density and the ΔEc. These results were related to hydrogen atoms and carbon related defects at the SiO2/4H-SiC (000-1) interface.

In many countries, 400 units (U) is the maximum dose of onabotulinumtoxinA available to treat upper limb spasticity, but few studies have demonstrated the optimal use of this dose. In the double-blind phase of this randomized, controlled trial, we compared the efficacy and safety of 400 vs. 240 U onabotulinumtoxinA in patients with post-stroke upper limb spasticity. Both groups received 240 U onabotulinumtoxinA injected in the forearm. An additional 160 U onabotulinumtoxinA (400 U group) or placebo (240 U group) was injected in the elbow flexors. Both groups showed similar muscle tone reduction in the wrist, fingers, and thumb; muscle tone reduction in the elbow flexors was greater in the group treated with onabotulinumtoxinA (400 U group) compared to placebo (240 U group). Functional disabilities improved in both groups. No substantial difference was found in safety profiles. In the subsequent open-label phase, all participants received repeat injections of 400 U onabotulinumtoxinA (target muscles and doses per muscle determined by the physician). Similar efficacy and safety outcomes, as with the 400 U group in the double-blind phase, were confirmed. This final report demonstrates that injection of onabotulinumtoxinA 400 U relieves muscle tone in a wide range of areas and improves functional disabilities; generally, it was well-tolerated, and no new safety concerns were identified. The dosing data in the open-label phase will inform optimal use of onabotulinumtoxinA in clinical practice (ClinicalTrials.gov: NCT03261167).

To evaluate the polarity, energy band diagram, and oxygen (O) distribution of a heavily Mg-doped InN (InN:Mg+) epilayer with a Mg concentration of 1.0±0.5×1020cm-3, the core-level and valence band (VB) photoelectron spectra are investigated by angle-resolved soft and hard X-ray photoelectron spectroscopies. The InN:Mg+ epilayers are grown by radio-frequency plasmaassisted molecular beam epitaxy. In this doping level, the polarity inversion from In-polar to N-polar occurs with the increase in the Mg flow rate under the same growth conditions, and the VB spectrum clearly indicates the direction of polarity of InN:Mg+, which is N-polar. The energy band diagram is considered to exhibit a two-step downward bending structure due to the coexistence of the n+ surface electron accumulation layer and heavily Mg-doped p+ layer formed in the bulk. The O concentration rapidly increases until ∼4 nm with respect to the surface, which is deduced to be one of the reasons of the formation of the anomalous two-step energy band profile. [ABSTRACT FROM AUTHOR]