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Backgrounds: Distal pancreatectomy fistula risk score (D‐FRS) and DISPAIR‐FRS has not been widely validated for predicting postoperative pancreatic fistula (POPF) after distal pancreatectomy (DP). Methods: We retrospectively analysed 104 patients undergoing DP. The predictive value of the D‐FRS and DISPAIR‐FRS were compared. Risk factors associated with POPF were investigated by multivariate analysis. Results: Of the 104 patients, 23 (22.1%) were categorized into the POPF group (all grade B). The areas under the ROC (AUCs) of the D‐FRS (preoperative), D‐FRS (intraoperative), and DISPAIR‐FRS were 0.737, 0.809, and 0.688, respectively. Stratified by the D‐FRS (preoperative), the POPF rates in low‐risk, intermediate‐risk, and high‐risk groups were 5%, 22.6%, and 36.4%, respectively. By the D‐FRS (intraoperative), the POPF rates in low‐risk, intermediate‐risk, and high‐risk groups were 8.8%, 47.1%, and 47.4%, respectively. By the DISPAIR‐FRS, the POPF rates in low‐risk, intermediate‐risk, and extreme‐high‐risk groups were 14.8%, 23.8% and 62.5%, respectively. Body mass index and main pancreatic duct diameter were independent risk factors of POPF both in preoperative (P = 0.014 and P = 0.033, respectively) and intraoperative (P = 0.015 and P = 0.039) multivariate analyses. Conclusion: Both the D‐FRS (preoperative), D‐FRS (intraoperative), and DISPAIR‐FRS has good performance in POPF prediction after DP. The risk stratification was not satisfactory in current Asian cohort. [ABSTRACT FROM AUTHOR]

Summary: This work solves the distributed tracking problem for multi‐agent systems with bounded inputs over directed networks. Unlike existing results focusing only on the input amplitude saturation, both input amplitude and input rate saturation are taken into account, which are more challenging due to the coupled evolutions of input amplitudes and input rates. Firstly, relative disturbance observers are developed using relative state measurements to estimate the relative disturbances, where the estimation errors converge to zero within a finite time horizon. Subsequently, distributed tracking error observers are proposed by means of a novel bounded function to estimate the tracking errors, where the estimation errors will converge to zero. Then, an observer‐based saturated control strategy is designed to achieve the distributed tracking objective. Finally, simulations of DC‐DC buck converters tracking and vehicles formation are provided to verify the effectiveness of the control scheme. [ABSTRACT FROM AUTHOR]

Aims: Atrial fibrillation (AF) and heart failure (HF) often co‐exist and are closely intertwined. The impact of AF on the outcome of patients with heart failure with mildly‐reduced ejection fraction (HFmrEF) is not fully clear. This study aimed to investigate the impact of AF on the outcomes of hospitalized HFmrEF patients. Methods and results: The study included 1691 consecutive patients with HFmrEF (mean 68.2 years, 64.8% male) including 296 AF patients. Patients completed 1 year and mean of 33 month clinical follow‐up after discharge by telephone interview, clinical visit, or community visit. The primary endpoint was cerebro‐cardiovascular events (CCE, composite of HF rehospitalization, stroke, or cardiovascular death). After propensity score matching, 296 patients were included into the AF group (mean 71.5 years) and 592 patients into the non‐AF group (mean 70.6 years). After propensity score matching, CCE at 1 year (59.1% vs. 48.5%, P = 0.003) and at a mean of 33 month (77.0% vs. 70.6%, P = 0.043). AF was independently associated with increased CCE within 1 year (HR = 1.31, 95% CI 1.07 to 1.61, P = 0.010) and at 33 months (HR = 1.20, 95% CI 1.00 to 1.43, P = 0.050) post‐discharge after adjusted for other clinical confounders including discharge heart rate, NT‐proBNP, haemoglobin, and uric acid. Conclusions: AF is independently associated with an increased risk of CCE in HFmrEF patients within 1 year and at a mean of 33 months after discharge. [ABSTRACT FROM AUTHOR]

Background: Anemia is associated with increased rates of heart failure (HF)‐related mortality and hospitalization. No studies have focused on the association between the red blood cell (RBC) count and the prognosis of patients with HF with mildly reduced left ventricular ejection fraction (HFmrEF). We retrospectively analyzed the effect of the RBC count on outcome events in patients with HFmrEF. Methods: We investigated the association of the RBC count with outcome events in 1691 patients with HFmrEF (mean age: 68 years; 35% female) in Xiangtan Central Hospital. Using Cox proportional hazards models, the RBC count was assessed as both a continuous and categorical variable. Results: During follow‐up (median: 33 months), cardiovascular death occurred in 168 patients (114 men and 54 women). After adjusting for established risk factors, each 1.0 × 1012 cell/L increase in the RBC count was associated with a 28% lower risk of cardiovascular death in men and a 43% lower risk in women. Patients with low RBC counts had a 0.5‐fold higher risk of cardiovascular death than those with normal RBC counts. The hazard ratio for men was 1.42 (95% confidence interval [CI]: 1.07–1.89), and the hazard ratio for women was 1.79 (95% CI: 1.20–2.67). The RBC count was not significantly associated with the composite endpoint of cardiovascular death and HF readmission (cardiovascular events) (p >.05). Conclusions: A decreased RBC count is associated with increased cardiovascular mortality in patients with HFmrEF. Correcting a low RBC count might potentially reduce the risk of cardiovascular death in patients with HFmrEF. [ABSTRACT FROM AUTHOR]

This work studies the prescribed‐time robust consensus tracking problem of heterogeneous multi‐agent systems over directed graphs. Aiming at multi‐agent systems with a static leader and only matched disturbances, a distributed observer‐based consensus algorithm is developed, to ensure that the tracking errors converge to zero accurately in prescribed time. For the case of multi‐agent systems with a dynamic leader and mismatched/matched disturbances, an adaptive strategy based on a distributed observer and a disturbance observer is designed by the dynamic damping reciprocal technology. Such strategy can avoid the numerical singularity, adapt to the situation that the upper bounds of the disturbances are unknown, and assure that the tracking errors converge to an adjustable neighborhood of zero within prescribed time. Finally, simulations are given to verify the effectiveness of the proposed control strategies. [ABSTRACT FROM AUTHOR]

Aims: Clinical data on the prognostic determinants over varying periods within the same cohort of heart failure with mid‐range or mildly reduced ejection fraction (HFmrEF) remain scarce. This study aimed to identify the short‐term, intermediate‐term, and long‐term risk factors of adverse cardiovascular (CV) outcomes in patients hospitalized for HFmrEF. Methods and results: This retrospective study included 1691 consecutive HFmrEF patients admitted to our hospital between January 2015 and August 2020. Baseline data including clinical characteristics, laboratory and cardiac imaging examinations were obtained. Patients completed at least 1 year clinical follow‐up after discharge by telephone interview, clinical visit, or community visit. The primary endpoint was defined as a composite of CV death or rehospitalization for heart failure (CV events) at 3, 12, and 33 months after the diagnosis of HFmrEF. Mean age of the whole cohort was 69 (61–77) years and 64.8% were male. The median clinical follow‐up was 33 (20–50) months. CV events were 17.5%, 28.2%, and 57.8% at 3, 12, and 33 months after discharge, respectively. Independent risk factors for CV events were uric acid >382 μmol/L, creatinine >100 μmol/L, N‐terminal pro‐B type natriuretic peptide (NT‐proBNP) > 3368 pg/mL and haemoglobin <120 g/L for men and <110 g/L for women at 3 and 12 months. Pulmonary artery systolic pressure >35 mmHg and the ratio of early transmitral flow velocity to early mitral annular velocity >18 served as independent risk factors for CV events at 12 months. At 33 months, uric acid > 382 μmol/L, NT‐proBNP >3368 pg/mL, and pulmonary artery systolic pressure >35 mmHg were the independent risk factors of CV events. Conclusions: Higher uric acid, creatinine, NT‐proBNP, and lower haemoglobin levels at baseline are valuable serum biomarkers for risk stratification of short‐term and long‐term CV outcomes of HFmrEF patients. Future studies are needed to verify if intensive heart failure therapy for identified high‐risk HFmrEF patients based on these four serum biomarkers could improve their short‐term and long‐term CV outcomes or not. [ABSTRACT FROM AUTHOR]

Aims: Pulmonary congestion (PC) expressed by residual lung ultrasound B‐lines (LUS‐BL) could exist in some discharged heart failure (HF) patients, which is a known determinant of poor outcomes. Detection efficacy for PC is suboptimal with widely used imaging modalities, like X‐ray or echocardiography, while lung ultrasound (LUS) can sufficiently detect PC by visualizing LUS‐BL. In this trial, we sought to evaluate the impact LUS‐BL‐guided intensive HF management post‐discharge on outcome of HF patients discharged with residual LUS‐BL up to 1 year after discharge. IMP‐OUTCOME is a prospective, single‐centre, single‐blinded, randomized cohort study, which is designed to investigate if LUS‐BL‐guided intensive HF management post‐discharge in patients with residual LUS‐BL could improve the clinical outcome up to 1 year after discharge or not. Methods and results: After receiving the standardized treatment of HF according to current guidelines, 318 patients with ≥3 LUS‐BL assessed by LUS within 48 h before discharge will be randomly divided into the conventional HF management group and the LUS‐BL‐guided intensive HF management group at 1:1 ratio. Patient‐related basic clinical data including sex, age, blood chemistry, imaging examination, and drug utilization will be obtained and analysed. LUS‐BL will be assessed at 2 month interval post‐discharge in both groups, but LUS‐BL results will be enveloped in the conventional HF management group, and diuretics will be adjusted based on symptom and physical examination results with or without knowing the LUS‐BL results. Echocardiography examination will be performed for all patients at 12 month post‐discharge. The primary endpoint is consisted of the composite of readmission for worsening HF and all‐cause death during follow up as indicated. The secondary endpoints consisted of the change in the New York Heart Association classification, Duke Activity Status Index, N terminal pro brain natriuretic peptide value, malignant arrhythmia event and 6 min walk distance at each designed follow up, echocardiography‐derived left ventricular ejection fraction, and number of LUS‐BL at 12 month post‐discharge. Safety profile will be recorded and managed accordingly for all patients. Conclusions: This trial will explore the impact of LUS‐BL‐guided intensive HF management on the outcome of discharged HF patients with residual LUS‐BL up to 1 year after discharge in the era of sodium‐glucose cotransporter‐2 inhibitors and angiotensin receptor blocker‐neprilysin inhibitor. Trial Registration: ClinicalTrials.gov: NCT05035459 [ABSTRACT FROM AUTHOR]

Chronic heart failure is one of the common causes of hospitalization and death. Pulmonary congestion is the common disease feature of patients with chronic heart failure, which could be correctly diagnosed by lung ultrasound. Efficacy of lung ultrasound‐guided pulmonary congestion management for patients with acute heart failure is well documented, however, more evidence is needed to establish the clinical value of pulmonary congestion detection by lung ultrasound examination in patients with chronic heart failure. This review summarized current evidence related to the use and clinical value of pulmonary congestion assessment by lung ultrasound in patients with chronic heart failure, aiming to provide new suggestions on promoting the widespread use of lung ultrasound in patients with chronic heart failure to improve the quality of life and outcome of patients with chronic heart failure. [ABSTRACT FROM AUTHOR]

Becker muscular dystrophy (BMD) complicated with DCM is rare in our daily clinical practice. BMD serves an etiology for heart failure patients due to DCM. Multidisciplinary management is required in this case. [ABSTRACT FROM AUTHOR]

This paper aims to propose a novel idea for the modeling and trajectory tracking control of a lower limb rehabilitation robot. A polynomial nonlinear uncertain model is established to deal with the difficulty of accurate modeling for the lower limb rehabilitation robot with complex dynamic characteristics. A high‐order nonlinear disturbance observer (HONDO) is utilized to estimate the lumped disturbance with fast time‐varying and the corresponding observer gain matrix is obtained by H∞ performance. Then an HONDO‐based composite tracking controller is designed to achieve good tracking performance of the lower limb rehabilitation robot. In addition, all solvability conditions can be directly handled by sum of squares programming, effectively avoiding the calculation problem. Finally, numerical simulations are conducted to verify the validity of the proposed method. [ABSTRACT FROM AUTHOR]

Summary: In this paper, the domain of attraction (DA) and the local stabilization problem are investigated under the nonlinear parameter‐varying (NPV) framework. Specifically, to take into account the time‐varying parameter, we generalize the definition of robust DA (RDA) and propose the concept of parameter‐dependent DA (PDA) for NPV systems, together with the sum‐of‐squares (SOS) conditions for their estimations. Differently from the existing DA‐related works, the theoretical results in this paper can be applied to a large class of nonlinear polynomial systems including the time‐invariant, the parameter‐dependent, and the uncertain ones. Moreover, the commonly used iterative/coordinate‐wise search is avoided because we eliminate the bilinear product terms between the Lyapunov functional and the SOS multipliers. We also consider the local stabilization problem of NPV systems, in which the RDA can be specified as a control performance index. Finally, several examples are given for illustration purposes. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the application value of a three-dimensional (3D) printing model in the training of choledochoscopy techniques.Materials and methods: Imaging data from two patients with biliary dilatation were used to produce two 3D reconstruction models which were subsequently constructed into 3D printing models (No. 1 and No. 2). Four hepatobiliary surgeons evaluated the anatomical accuracy and academic teaching value of the printed models. Twenty resident trainees with no prior experience in any kind of endoscopic techniques were randomly and symmetrically divided into two groups. The training group (A) used the 3D model No. 1 in the learning of biliary tract anatomy and practice techniques of choledochoscopy. The control group (B) got the virtual 3D image of the same model on computer for learning. After 4 weeks, the model No. 2 was used to reassess the trainees’ subjective and objective progress in anatomy familiarity and choledochoscopy manipulations.Results: All consulted surgeons agreed that the 3D models realistically reproduced the anatomy of the biliary system. All trainees in group A agreed or strongly agreed that the 3D models provided good anatomical realism, enhanced their experience in the training of choledochoscopy techniques, and aided in their learning of biliary anatomy. With the practice went on, they increased the accuracy and showed a reduction in operation time on the model No. 1. During final examination with model No. 2, the rate of correct anatomical structure identification in training group was significantly higher than group B (p < 0.05).Conclusion: The 3D printed biliary tract model is an excellent teaching tool in the training of choledochoscopy techniques. The 3D model is anatomically realistic and can improve the trainee’s anatomical knowledge and endoscopic skills. [ABSTRACT FROM AUTHOR]

Summary: This paper generalizes the existing finite‐time stability (FTS) analysis/synthesis research to nonlinear time‐varying systems in the nonlinear parameter‐varying (NPV) framework. Specifically, to guarantee both the transient and steady‐state performances for NPV systems with external disturbance and input constraints, concepts of mixed stability and mixed stability with H∞ disturbance attenuation are proposed, together with the corresponding analysis and synthesis methods. Differently from the existing FTS‐related works, the mixed stability in this paper consists of properties of uniform exponential stability in addition to FTS. Existence conditions for an nonlinear time‐varying controller to render an NPV system mixed stable with H∞ disturbance attenuation are given in terms of state‐and‐parameter–dependent linear matrix inequalities. The generalized S‐procedure is used to convexify the input constraints such that the resulting closed‐loop system satisfies the input constraints for any state starting from an admissible set. For the case that both parameters and state are subject to restricted regions, local synthesis results are also provided. All the conditions are in the form of state‐and‐parameter–dependent linear matrix inequalities, which can be efficiently solved by using sum‐of‐squares programming. A simulation example validates the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

In circulating water system , methyl benzotriazole (TTA) is one of the common corrosion inhibitors for copper. But the inhibition mechanisms have not been clearly understood so far. In different number of water molecules, the interaction between TTA and Cu2O (copper surface) was investigated with molecular dynamics (MD) method. The results showed that the MD simulation result with water was more consistent with the experiment results. In different number of water molecules, the sequence of the interaction energies between TTA and Cu2O (001) was ∆ E1 (150H2O) > ∆ E1(200H2O) > ∆ E1(100H2O) > ∆ E1(50H2O) > ∆ E1(0H2O). The number of water molecules had an important influence on the interaction between corrosion inhibitors and Cu2O crystal. From non-bond energy and pair correlation functions, the interaction energies of the model system were mainly contributed by the non-bond interaction. Strong adsorption could be raised by the Coulomb interaction between the negatively charged functional groups in TTA and the positive copper ions in the Cu2O (001) face, and further interaction between aggressive media and copper could be restricted. So, copper corrosion could be avoided. Chemical bonds and non-bond interactions were formed between TTA and Cu2O (001) in different number of water molecules. Water molecules could not be ignored during the MD simulation, too. The results obtained here may provide theoretical supports for developing new corrosion inhibitors. [ABSTRACT FROM AUTHOR]

This study focuses on the observer‐based non‐linear H∞ (OBNH) attitude control for a flexible satellite with external disturbances and local state‐region constraints. By considering the structural features of the attitude system and applying Lyapunov stability theory, the solvable conditions of the OBNH attitude control problem are provided. An advantage of this study is that the state‐feedback controller and the reduced‐order state observer can be designed independently, thus significantly reducing the complexity of the attitude control algorithm. Furthermore, based on the polynomial sum of squares (SOSs) and the generalised S ‐procedure techniques, the above problem can be transformed into a convex optimisation problem with SOS constraints. This conversion can effectively overcome the computational difficulties widely present in the control problem of non‐linear systems. Finally, a numerical example is given to illustrate the effectiveness and feasibility of the proposed approach. [ABSTRACT FROM AUTHOR]

ABSTRACT In this letter, Ti/Pt/Au metal system has been investigated for the source/drain contact of MHEMT, the Ti/Pt/Au contact exhibits good ohmic contact characteristics with well thermal stability in the temperature range from 280 to 340°C. To further optimize the contact resistance, different metal deposition methods and contact layers are experimentally investigated. With sputtering Pd as an interlayer between Ti/Pt/Au and n+-InGaAs, the specific contact resistivity is further reduced to 3.51 × 10−5 Ω cm2. Meanwhile, by adopting this metal contact system, the MHEMT shows good DC and RF characteristics, including full channel current of 75 mA/mm, extrinsic maximum transconductance gm.max of 96 ms/mm, unity current gain cutoff frequency fT of 60 GHz and maximum frequency of oscillation fmax of 156 GHz. These good electrical characteristics demonstrate that this metal contact system is beneficial for the performance improvement of MHEMT. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:217-221, 2016 [ABSTRACT FROM AUTHOR]

Liver-directed gene therapy has become a promising treatment for many liver diseases. In this study, we constructed a multi-functional targeting molecule, which maintains targeting, endosome-escaping, and DNA-binding abilities for gene delivery. Two single oligonucleotide chains of Melittin (M) were synthesized. The full-length cDNA encoding anti-hepatic asialoglycoprotein receptor scFv C1 (C1) was purified from C1/pIT2. The GAL4 (G) gene was amplified from pSW50-Gal4 by polymerase chain reaction. M, C1 and G were inserted into plasmid pGC4C26H to product the recombinant plasmid pGC-C1MG. The fused gene C1MG was subsequently subcloned into plasmid pET32c to product the recombinant plasmid C1MG/pET32c and expressed in Escherichia coli BL21. The scFv-Mel-Gal4 triple fusion protein (C1MG) was purified with a Ni2+ chelating HiTrap HP column. The fusion protein C1MG of roughly 64 kD was expressed in inclusion bodies; 4.5 mg/ml C1MG was prepared with Ni2+ column purification. Western blot and immunohistochemistry showed the antigen-binding ability of C1MG to the cell surface of the liver-derived cell line and liver tissue slices. Hemolysis testing showed that C1MG maintained membrane-disrupting activity. DNA-binding capacity was substantiated by luciferase assay, suggesting that C1MG could deliver the DNA into cells efficiently on the basis of C1MG. Successful expression of C1MG was achieved in E. coli, and C1MG recombinant protein confers targeting, endosome-escaping and DNA-binding capacity, which makes it probable to further study its liver-specific DNA delivery efficacy in vivo. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Radiative and nonradiative processes in deep ultraviolet (DUV) AlGaN/AlGaN multiple quantum wells (MQWs) grown by LP-MOCVD have been studied by means of deep ultraviolet time-integrated photoluminescence (PL) and time-resolved photoluminescence (TRPL) spectroscopy. As the temperature is increased, the peak energy of DUV-AlGaN/AlGaN MQWs PL emission ( Ep) exhibits a similarly anti-S-shaped behavior (blueshift - accelerated redshift - decelerated redshift): Ep increases in the temperature range of 5.9-20 K and decreases for 20-300 K, involving an accelerated redshift for 20-150 K and an opposite decelerated redshift for 150-300 K with temperature increase. Especially at high temperature as 300 K, the slope of the Ep redshift tends towards zero. This temperature-induced PL shift is strongly affected by the change in carrier dynamics with increasing temperature. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

For Al-rich AlGaN which is applied to deep ultraviolet LEDs, improving doping efficiency without cracking problem is one of the most important research issues. Delta-doping technique offers a promising approach. In this study, we report delta-doping experiments in high aluminum content n-AlxGa1-xN (x=0.55) grown by MOCVD and investigate the effect of the growth technique. In the experiment we designed, a uniformly-doped sample (reference sample) and three delta-doping samples with varying delta-doping time (6 s, 15 s, and 30 s) were fabricated on AlN templates. Measured by high-resolution X-ray diffraction (HR-XRD) ω-scan and atomic-force microscope (AFM), samples with delta-doping technique show better crystal quality. Moreover, tested by contactless sheet resistance and Hall-effect test, delta-doping samples exhibit better electrical property with lower sheet resistance, higher carrier mobility, and larger carrier density. When increasing delta-doping time, all properties were gradually improved. These improvements were attributed to SiNx-growth-mask and dislocation-blocking effect induced by delta-doping technique. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]