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Objectives: We aimed to explore imaging features including tissue characterization and myocardial deformation in diabetic heart failure with preserved ejection fraction (HFpEF) patients by magnetic resonance imaging (MRI) and investigate its prognostic value for adverse outcomes. Materials and methods: Patients with HFpEF who underwent cardiac MRI between January 2010 and December 2016 were enrolled. Feature-tracking (FT) analysis and myocardial fibrosis were assessed by cardiac MRI. Cox proportional regression analysis was performed to determine the association between MRI variables and primary outcomes. Primary outcomes were all-cause death or heart failure hospitalization during the follow-up period. Results: Of the 335 enrolled patients with HFpEF, 191 had diabetes mellitus (DM) (mean age: 58.7 years ± 10.8; 137 men). During a median follow-up of 10.2 years, 91 diabetic HFpEF and 56 non-diabetic HFpEF patients experienced primary outcomes. DM was a significant predictor of worse prognosis in HFpEF. In diabetic HFpEF, the addition of conventional imaging variables (left ventricular ejection fraction, left atrial volume index, extent of late gadolinium enhancement (LGE)) and global longitudinal strain (GLS) resulted in a significant increase in the area under the receiver operating characteristic curve (from 0.693 to 0.760, p < 0.05). After adjustment for multiple clinical and imaging variables, each 1% worsening in GLS was associated with a 9.8% increased risk of adverse events (p = 0.004). Conclusions: Diabetic HFpEF is characterized by more severely impaired strains and myocardial fibrosis, which is identified as a high-risk HFpEF phenotype. In diabetic HFpEF, comprehensive cardiac MRI provides incremental value in predicting prognosis. Particularly, MRI-FT measurement of GLS is an independent predictor of adverse outcome in diabetic HFpEF. Clinical relevance statement: Our findings suggested that MRI-derived variables, especially global longitudinal strain, played a crucial role in risk stratification and predicting worse prognosis in diabetic heart failure with preserved ejection fraction, which could assist in identifying high-risk patients and guiding therapeutic decision-making. Key Points: • Limited data are available on the cardiac MRI features of diabetic heart failure with preserved ejection fraction, including myocardial deformation and tissue characterization, as well as their incremental prognostic value. • Diabetic heart failure with preserved ejection fraction patients was characterized by more impaired strains and myocardial fibrosis. Comprehensive MRI, including tissue characterization and global longitudinal strain, provided incremental value for risk prediction. • MRI served as a valuable tool for identifying high-risk patients and guiding clinical management in diabetic heart failure with preserved ejection fraction. [ABSTRACT FROM AUTHOR]

Cardiac power output (CPO) is a powerful predictor of adverse outcomes in heart failure (HF). However, the original formula of CPO included the difference between mean arterial pressure and right atrial pressure (RAP). The prognostic performance of RAP-corrected CPO (CPORAP) remains unknown in heart failure with preserved ejection fraction (HFpEF). We studied 101 HF patients with a left ventricular ejection fraction > 40% who had pulmonary hypertension due to left heart disease. CPORAP was significantly more discriminating than CPO in predicting outcomes (Delong test, P = 0.004). Twenty-five (24.8%) patients presented with dis-concordantly high CPORAP and low CPO when stratified by the identified CPORAP threshold of 0.547 W and the accepted CPO threshold of 0.803 W. These patients had the lowest RAP, and their cumulative incidence was comparable with those with concordantly high CPO and CPORAP (P = 0.313). CPORAP might identify patients with right ventricular involvement, thereby providing better prognostic performance than CPO in HFpEF. [ABSTRACT FROM AUTHOR]

To enhance the corrosion resistance of magnesium alloy while improving its surface roughness to enhance organic bonding, the single pulse micro-arc oxidation treatment was conducted on magnesium alloy specimens for a duration of 1200 seconds. The treatment employed a mixed electrolyte of Na3PO4/Na2SiO3 with varying proportions, aiming primarily to investigate the treatment mechanism. Voltage–time response curves were recorded throughout the entire process. Characterization of the bioceramic films was achieved through the application of SEM, XRD, and XPS techniques, elucidating phase formation, surface morphologies, elemental distribution, and chemical valence. Subsequently, measurements were taken to assess the porosity of the film layer, alterations in thickness, roughness, and the kinetic potential polarization curves. The experimental findings reveal that P and Si elements influence the performance of AZ91D MAO coating by affecting cascading discharge and channel blockage. When the concentration ratio of PO43−/SiO32− in the mixed electrolyte reached 0.02 mol L−1/0.08 mol L−1, the icorr of MAO coating measured 4.6391 μA cm−2, indicating better corrosion resistance. [ABSTRACT FROM AUTHOR]

Evidence-based management of decongestion is lacking in hospitalized heart failure (HHF) patients, especially in patients with impaired renal function. Hemoconcentration is an objective measure of decongestion that portends a favorable prognosis and guides management in HHF patients with preserved renal function. We aim to investigate whether it remains a prognosticator in patients with renal impairment, and to refine the identification of subpopulations who will benefit from hemoconcentration-guided therapy. HHF patients admitted to Heart Failure Center of Fuwai Hospital were consecutively included from December 2006 to June 2018. Patient characteristics were depicted. Relationships between in-hospital hemoconcentration, worsening renal function (WRF), and one-year all-cause mortality were investigated in the total population and compared between renal function groups using survival analysis and cubic splines, with a special focus on renal function-based interactions. The association was further validated in sensitivity analyses. Clinically relevant cut-offs and subpopulations were identified by subpopulation treatment effect pattern plots (STEPP) and subgroup analysis. 3661 participants (30.4% with impaired renal function) were included. Hemoconcentration, reflected by an in-hospital increase in hemoglobin, hematocrit, or a relative reduction in estimated plasma volume from baseline to discharge, was predictive of decreased one-year mortality in the total cohort despite its correlation with higher WRF incidence. The prognostic value of hemoconcentration differed in patients with impaired and preserved renal function. Hemoconcentration was related to a favorable prognosis in patients with preserved renal function (HR, 0.69; 95% CI, 0.53–0.90; P = 0.007), especially in young male patients with New York Heart Association functional class III–IV, reduced ejection fraction, and baseline eGFR > 75 mL/min/1.73m2. Contrarily, impaired renal function patients experienced a higher incidence of WRF, and hemoconcentration was no longer related to outcome (HR, 0.90; 95% CI, 0.64–1.26; P = 0.545), with findings consistent in all clinically relevant subgroups. In HHF patients, the prognostic value of hemoconcentration differs by renal function, and the clinical utility of hemoconcentration is contingent on preserved renal function. [ABSTRACT FROM AUTHOR]

Background: Accumulating evidence links the echinoderm microtubule-associated protein-like 4 (EML4)-anaplastic lymphoma kinase (ALK) rearrangement to venous thromboembolism (VTE) in non-small cell lung cancer (NSCLC) patients. However, the corresponding mechanisms remain unclear. Method: High-throughput sequencing analysis of H3122 human ALK-positive NSCLC cells treated with ALK inhibitor/ dimethyl sulfoxide (DMSO) was performed to identify coagulation-associated differential genes between EML4-ALK fusion protein inhibited cells and control cells. Sequentially, we confirmed its expression in NSCLC patients' tissues and in the plasma of a subcutaneous xenograft mouse model. An inferior vena cava (IVC) ligation model was used to assess clot formation potential. Additionally, pathways involved in tissue factor (TF) regulation were explored in ALK-positive cell lines H3122 and H2228. Statistical significance was determined by Student t-test and one-way ANOVA using SPSS. Results: Sequencing analysis identified a significant downregulation of TF after inhibiting EML4-ALK fusion protein activity in H3122 cells. In clinical NSCLC cases, TF expression was increased especially in ALK-positive NSCLC tissues. Meanwhile, H3122 and H2228 with high TF expression exhibited shorter plasma clotting time and higher TF activity versus ALK-negative H1299 and A549 in cell culture supernatant. Mice bearing H2228 tumor showed a higher concentration of tumor-derived TF and TF activity in plasma and the highest adjusted IVC clot weights. Limiting EML4-ALK protein phosphorylation downregulated extracellular regulated protein kinases 1/2 (ERK1/2)-activating the protein-1(AP-1) signaling pathway and thus attenuated TF expression. Conclusion: EML4-ALK fusion protein may enhance venous thrombogenicity by regulating coagulation factor TF expression. There was potential involvement of the pERK1/2-AP-1 pathway in this process. [ABSTRACT FROM AUTHOR]

Background: Estimated plasma volume status (ePVS) is a marker of intravascular congestion and has prognostic value in patients with heart failure (HF). The elevation of intracardiac filling pressures is defined as hemodynamic congestion and is also associated with poor prognosis. However, the relationship between intravascular congestion and hemodynamic congestion remains unclear. This study sought to explore the correlation between ePVS and hemodynamic parameters and determine the association between ePVS and clinical outcomes in patients with advanced HF. Methods: Patients with advanced HF underwent right heart catheterization (RHC) for hemodynamic profiles. The sum of right atrial pressure (RAP) and pulmonary arterial wedge pressure (PAWP) > 30 mmHg was considered to present with hemodynamic congestion. Blood tests were conducted within 24 h of RHC. We calculated ePVS using the Strauss-derived Duarte formula. The primary outcome was all-cause mortality. Results: A total of 195 patients were divided into two groups based on the cut-off value of ePVS (4.08 dL/g) calculated from receiver operating characteristic analysis. Patients with ePVS > 4.08 dL/g were more likely to present with wet rales (21.2% vs. 9.9%, P = 0.032) and had a higher risk of death (HR 4.748, 95% CI 2.385–9.453), regardless of whether RAP + PAWP was normal or elevated (all P < 0.05). Hemodynamic parameters and ePVS were not correlated (all P > 0.05). High ePVS significantly improved the predictive value beyond the clinical plus hemodynamic prognostic model (area under the curve of 0.844, Delong test, P = 0.024). Conclusion: ePVS could additionally add prognostic value to hemodynamic parameters in advanced heart failure, although not correlated with hemodynamic parameters. [ABSTRACT FROM AUTHOR]

Bayesian optimization (BO) is an effective optimization technique for solving expensive black-box problems. Even though BO has remarkable success, its drawbacks are also obvious. First, the time complexity of the Gaussian process inference is higher than O(n3), where n is the number of samples. Consequently, the running time of BO increases rapidly with the problem size. Second, due to the non-convexity and multimodality of the acquisition function, it costs a lot to achieve good results. To address the above problems, we develop a local Bayesian optimization algorithm based on the trust region idea (TRLBO). In TRLBO, two trust regions with dynamically changing sizes are used to enhance the algorithm's exploitation ability, while at the same time retaining the exploration ability. Specifically, one trust region is used to reduce the number of samples in the Gaussian process. The other is used to restrict the solution space of the candidates. Furthermore, some theoretical results were provided to enlighten the efficiency of the proposed algorithm. Experimental results on both benchmark functions and real-world problems show that TRLBO compares favorably with the state-of-the-art algorithms. [ABSTRACT FROM AUTHOR]

Arsenic species in copper smelting ash have an important effect on recovery of valuable metals and ecological conservation. In this study, a new process for removing and collecting As by sulfurization roasting and then shock cooling was proposed. The Ellingham diagrams of the reactions among arsenic species, sulfuric acid and carbon and the As-O-S system isothermal dominance zone diagram were developed using HSC 6.0. They indicate that temperature and atmosphere were important for removal of As. XPS results show that As, Zn, Bi and Pb mainly existed in the form of oxides and sulfates in the ash. TG–DSC results indicate that the ash had four stages of thermogravimetry and heating rate affected the removal of As. The addition of sulfuric acid and anthracite, time and temperature had important effects on As removal. The optimum conditions were as follows: 350°C, 3 h, 10% anthracite and sulfuric 0.3 ml/g acid addition. Under these conditions, > 95% of As was volatilized and > 99% of As was collected. XRD result of the roasted slags shows that the diffraction peaks of As-related phases were disappeared. SEM/EDS results of off-gases condensates show that the condensates were cubic crystals of As2O3 containing 64.7 ± 0.6% As. [ABSTRACT FROM AUTHOR]

Natural ceramide, a biologically active compound present in plants, has been used widely in food, cosmetics, and pharmaceutical industries. Abundant ceramide has been detected in sewage sludge, which has inspired the idea to recycle ceramide from it. Therefore, the methods of extracting, purifying, and detecting ceramides from plants were reviewed, with the aim to establish methods to get condensed ceramide from sludge. Ceramide extraction methods include traditional methods (maceration, reflux, and Soxhlet extraction) and green technologies (ultrasound-assisted, microwave-assisted, and supercritical fluid extraction). In the past two decades, more than 70% of the articles have used traditional methods. However, green extraction methods are gradually improved and showed high extraction efficiency with lower solvent consumed. The preferred technique for ceramide purification is chromatography. Common solvent systems include chloroform–methanol, n-hexane–ethyl acetate, petroleum ether-ethyl acetate, and petroleum ether-acetone. For structural determination of ceramide, infrared spectroscopy, nuclear magnetic resonance spectroscopy, and mass spectrometry are used in combination. Among quantitative analysis methods for ceramide, liquid chromatography–mass spectrometry was the most accurate. This review concludes that with our prilemenary experiment results it is feasible to apply the plant "extraction + purification" process of ceramide to sludge, but more optimization need to be performed to get better results. [ABSTRACT FROM AUTHOR]

Community structure is one of the most significant features in complex networks and community detection is a crucial method to analyze community structure. Existing representations in community detection have the characteristics of inflexibility and easily generate invalid solutions. To address the drawbacks, this paper proposed a multi-objective evolutionary algorithm based on mixed encoding (MOGAME). The algorithm combines the locus-based representation and labels-based representation, which can avoid generating invalid solution and improve the performance. Extensive experiments on both synthetic and real-word networks show that the proposed algorithm performs better than the existing algorithms with respect to accuracy and stability. [ABSTRACT FROM AUTHOR]

Drug resistance is a major obstacle to the successful treatment of cancer. The role of the miR-106b-25 cluster in drug resistance of haematologic malignancies has not yet been elucidated. Here, we show that the miR-106b-25 cluster mediates resistance to therapeutic agents with structural and mechanistic dissimilarity in vitro and in vivo. RNA sequencing data revealed that overexpression of the miR-106b-25 cluster or its individual miRNAs resulted in downregulation of multiple key regulators of apoptotic pathways. Luciferase reporter assay identified TP73 as a direct target of miR-93 and miR-106b, BAK1 as a direct target of miR-25 and CASP7 as a direct target of all three miRNAs. We also showed that inhibitors of the miR-106b-25 cluster and BCL-2 exert synergistic effects on apoptosis induction in primary myeloid leukaemic cells. Thus, the members of the miR-106b-25 cluster may jointly contribute to myeloid leukaemia drug resistance by inactivating multiple apoptotic genes. Targeting this cluster could be a promising combination strategy in patients resistant to therapeutic agents that induce apoptosis. [ABSTRACT FROM AUTHOR]

An essential component of the hematopoietic microenvironment, bone marrow mesenchymal stem cells (BM-MSCs) play an important role in the homeostasis and pathogenesis of the hematopoietic system by regulating the fate of hematopoietic stem cells (HSCs). Previous studies revealed that BM-MSCs were functionally remodeled by malignant cells in leukemia. However, the alterations in BM-MSCs in polycythemia vera (PV) and their effects on HSCs still need to be elucidated. Our results demonstrated that although BM-MSCs from PV patients shared similar surface markers with those from healthy donors, they exhibited enhanced proliferation, decreased senescence, and abnormal osteogenic differentiation capacities. The CD146+CD271+ BM-MSC subpopulation, which is considered to give rise to typical cultured BM-MSCs and form bone and the hematopoietic stroma, was then sorted. Compared with those from healthy donors, CD146+CD271+ BM-MSCs from PV patients showed an impaired mesensphere formation capacity and abnormal differentiation toward osteogenic lineages. In addition, CD146+CD271+ PV BM-MSCs showed altered hematopoietic supportive activity when cocultured with cord blood CD34+ cells. Our study suggested that remodeled CD146+CD271+ BM-MSCs might contribute to the pathogenesis of PV, a finding that will shed light on potential therapeutic strategies for PV. [ABSTRACT FROM AUTHOR]

Background: Ivabradine improves cardiac function and clinical outcomes in chronic heart failure (HF) by reducing heart rate (HR), but there is a lack of real-world data on its effectiveness and safety in Chinese patients. Methods: We designed a prospective, multicenter, observational study of Chinese adults with HF and left ventricular systolic dysfunction, resting HR ≥ 75 beats per minute (bpm), and an indication for ivabradine treatment. An interim analysis was performed using a cut-off date of 31 October 2019. The primary outcome was change in HR at 6 months after the initiation of ivabradine. Secondary endpoints included change in New York Heart Association (NYHA) functional class; quality of life (QoL), measured using the Kansas City Cardiomyopathy Questionnaire (KCCQ); and adverse events (AEs). Results: Overall, 655 subjects were included in the interim analysis. Mean reduction in HR from baseline was 13.2 (95% confidence interval [CI] 11.2–15.2) bpm at Month 1, and 14.5 (95% CI 11.8–17.2) bpm at Month 6 (p < 0.001 for both changes). NYHA functional class and KCCQ scores improved significantly over time (p < 0.001 for all comparisons with baseline), indicating amelioration of symptoms and better QoL, respectively. Forty-four subjects (6.7%) reported a total of 60 ivabradine-related AEs, most frequently phosphenes and bradycardia (both n = 6, 0.9%). Conclusion: Treatment with ivabradine for 6 months effectively reduced HR and improved functional class and QoL in Chinese patients with chronic HF. Treatment was well tolerated. Clinical Trial Registration: ISRCTN11703380; registered on 8 November 2016. [ABSTRACT FROM AUTHOR]

The functionalized organic polymer monolithic column was synthesized in a stainless steel column (4.6 mm i.d. × 100 mm). 1,6-Hexanediol dimethacrylate and 1-allyl-3-methylimidazole chloride were designed as bifunctional monomers, methanol and dodecanol were used as porogens, and azobisisobutyronitrile was used as initiator. The prepared pre-polymerization solution was polymerized in a water bath at 60 °C. In the preparation process, the resolution and peak shape of phenanthrene, biphenyl and benzene were chosen as indicators to optimize the addition amount of 1-allyl-3-methylimidazole chloride. The monolithic column was used to separate neutral, phenolic and aniline compounds, and then the performance was evaluated. The results show the stationary phase permeability K = 3.49 × 10–12/m2, and the resolution R > 1.5 for various compounds. In addition, the retention mechanism of the monolithic column may be typical reversed-phase chromatography. The successful preparation of the monolithic column proves the hypothesis that the addition of ionic liquid can reduce the column pressure, and the prepared monolithic material can successfully separate three types of small molecule compounds. Ionic liquids can be regarded as a good modifier for organic polymer monolithic column. [ABSTRACT FROM AUTHOR]

Spark plasma sintering (SPS) was a promising method for repairing refractory waste targets. In this study, Mo-10Nb powders and Mo-10Nb waste targets were joined at variable temperatures by SPS for 10 min. The effects of temperatures (1400–1650 °C) on the interfacial microstructure, thermal conductivity, and mechanical properties were studied. It was unveiled that more Nb dissolved into the Mo lattice as temperature raised and all interfaces were defect-free. The electron back-scattered diffraction images revealed that the grain size of the powder-sintered body at 1550 °C was close to the original waste target. Besides, "90°" junctions were formed on the interface at 1400 °C, part of "120°" configurations were formed at 1450–1500 °C, and the interface was fused at 1550–1650 °C. The evolution of the interface structure was related to the intrinsic diffusion coefficient (D ) of Mo-10Nb. The D calculated from SPS densification data verified that D increased with the increase in joining temperatures, which enhanced the atomic flux through the interface and facilitated the interface fusion. Additionally, the combination of effects (grain size and porosity) improved the thermal conductivity. Besides, the relative density and microhardness raised with increasing temperatures. The bending strength increased first and then declined at 1650 °C, and the failure position was also different. Based on the relevant analysis, it was determined that the optimum temperature for repairing the waste refractory Mo-10Nb target was 1550 °C. [ABSTRACT FROM AUTHOR]

The ZCuSn10Pb10 alloy cladding was connected to the Q235 steel substrate by melting-casting. The semi-solid treatment of ZCuSn10Pb10 alloy was carried out by strain induced melt activation (SIMA) method, which included two stages of extrusion and partial remelting. Then the as-extruded ZCuSn10Pb10 alloy was joined with the Q235 steel substrate containing the cladding layer in the partial remelting stage. The microstructure, interfacial diffusion behavior and interfacial properties of the bimetallic composite were studied. The results showed that the diffusion behavior of elements at the copper/steel interface after semi-solid and cladding treatment was mainly reflected in the increase of the thickness of the diffusion layer of Sn and Cu elements. The average shear strength of the samples treated with semi-solid and cladding layer could reach 193.0 MPa, and the fracture occurred between the copper layer and the cladding layer. For semi-solid treated composite, the energy stored during pre-deformation and semi-solid slurry formed during remelting are important factors for forming a good interface. [ABSTRACT FROM AUTHOR]

Polydopamine (PDA) functionalized graphitic carbon nitride nanosheets (PDCN) and α-Fe2O3 nanoparticles (PDFe) were synthesized and characterized by FT-IR, XRD, TGA, XPS, and TEM. The complementary fillers of two-dimensional PDCN and zero-dimensional PDFe incorporated into waterborne epoxy (WEP) greatly improve the corrosion protect properties of composite coating, which was demonstrated through electrochemical impedance spectroscopy (EIS) and macroscopic surface morphology. Results showed that PDA modified g-C3N4 and α-Fe2O3 composite fillers (PDCN/Fe) have much superior synergistic effect on the improved barrier function of coatings than pure mixture of g-C3N4 and α-Fe2O3 (CN/Fe). This research indicates that the synergistic effect of nanofillers of different dimensions can be greatly stimulated by the good dispersibility in matrix, which has significant potential in improving corrosion protection properties of composite coatings. [ABSTRACT FROM AUTHOR]

For nonlinear third-order three-point boundary value problems (BVPs), we develop two algorithms to find solutions, which automatically satisfy the specified three-point boundary conditions. We construct a boundary shape function (BSF), which is designed to automatically satisfy the boundary conditions and can be employed to develop new algorithms by assigning two different roles of free function in the BSF. In the first algorithm, we let the free functions be complete functions and the BSFs be the new bases of the solution, which not only satisfy the boundary conditions automatically, but also can be used to find solution by a collocation technique. In the second algorithm, we let the BSF be the solution of the BVP and the free function be another new variable, such that we can transform the BVP to a corresponding initial value problem for the new variable, whose initial conditions are given arbitrarily and terminal values are determined by iterations; hence, we can quickly find very accurate solution of nonlinear third-order three-point BVP through a few iterations. Numerical examples confirm the performance of the new algorithms. [ABSTRACT FROM AUTHOR]

Magnesium (Mg) has a strong application potential as a lightweight metal. Yet, its absolute strength still needs improvement. In this work, we demonstrate that machine learning can be utilized to guide the development of high-strength Mg cast alloys. In the design framework, the composition and heat treatment condition are iteratively optimized by a surrogate model that is also evolving. After two iterations, a new alloy with the composition of Mg-10.0Al-2.0Sn-2.0Zn-0.1Ca-0.1Mn (at. pct) was identified. After aging at 200 °C for 96 hours, this alloy shows a Vickers hardness value of 110.5 Hv, which surpasses the highest value (102.5 Hv) in the initial dataset from literature. Finally, microstructure of the optimized alloy was characterized to understand the origin of its high hardness. This work demonstrates the potential of data-driven approaches for material development. [ABSTRACT FROM AUTHOR]

Large-scale layers peeling after the laser irradiation of dual ion beam sputtering coatings is discovered and a model is established to explain it. The laser damage morphologies relate to the laser fluence, showing thermomechanical coupling failure at low energy and coating layers separation at high energy. High-pressure gradients appear in the interaction between laser and coatings, resulting in large-scale layer separation. A two-step laser damage model including defect-induced damage process and ionized air wave damage process is proposed to explain the two phenomena at different energy. At relatively high energies (higher than 20 J/cm2), ionization of the air can be initiated, leading to a peeling off effect. The peeling effect is related to the thermomechanical properties of the coating materials. [ABSTRACT FROM AUTHOR]

We get an explicit and recursive representation for high order moments of integral-type downward functionals for single death processes. Meanwhile, main results are applied to more general integral-type downward functionals. [ABSTRACT FROM AUTHOR]

A new strategy was proposed that simultaneously improves the pervaporation (PV) performance and solvent resistance via the construction of a movable crosslinked structure in ethyl cellulose/polyvinylidene fluoride (EC/PVDF) composite membrane for the purpose of benzene/cyclohexane separation. Based on the molecular design of the macrocyclic compound cyclodextrin, polyrotaxane crosslinking agent (PR=) with a special sliding/rotating property and cavity structure was successfully synthesized. Furthermore, for convenient comparative study, cyclodextrin crosslinking agent (CD=) with cavity structure bereft of a sliding/rotating property and pentaerythritol triacrylate (PETA) without sliding/rotating property and cavity structure were prepared. The composite membranes were fabricated with crosslinking modified EC as active layer, together with PVDF support layer. The molecular structure and microstructure were confirmed. The pervaporation and swelling performance of the fabricated membranes for benzene/cyclohexane were investigated. PR= modified membranes showed good solvent resistance and exhibited a flux of 4332 g·m−2·h−1 and separation factor of 6.26, which was higher than CD= and PETA modified membranes. The results were attributed to the facilitated transport behavior, which was markedly related with the sliding/rotating property and cavity structure of polyrotaxane (PR). The related research provides interesting suggestions for PV membrane design for the separation of organic mixtures. [ABSTRACT FROM AUTHOR]

We present an explicit and recursive representation for high order moments of the first hitting times of single death processes. Based on that, some necessary or sufficient conditions of exponential ergodicity as well as a criterion on ℓ-ergodicity are obtained for single death processes, respectively. [ABSTRACT FROM AUTHOR]

An explicit and recursive representation is presented for moments of the first hitting times of birth-death processes on trees. Based on that, the criteria on ergodicity, strong ergodicity, and ℓ-ergodicity of the processes as well as a necessary condition for exponential ergodicity are obtained. [ABSTRACT FROM AUTHOR]

The leaching behavior of lead and silver from lead sulfate residues in NaCl-CaCl2-NaClO3 media was studied systematically. The results indicate that Cl− concentration, NaClO3 concentration, leaching time and temperature had significant effects on lead and silver leaching, whilst agitation speed and the liquid–solid ratio had a secondary effect on silver leaching but little effect on lead leaching. The Ca2+ concentration had an important effect on SO 4 2 - removal but little effect on lead and silver leaching. The optimum parameters for lead and silver leaching were: initial Cl− concentration: 207.5 g/L; NaClO3 concentration: 12 g/L; Ca2+ concentration: 1.3 times of stoichiometric quantity; temperature: 90 ± 2 °C; time: 1 h; liquid–solid ratio: 8:1–10:1; and agitation speed: 450 rpm. The lead and silver leaching were > 98% and 95%, respectively. The removal ratio of SO 4 2 - was > 98%. The leaching kinetics of lead follow the shrinking core model of mixed control, and the apparent activation energy was 13.4 kJ/mol. [ABSTRACT FROM AUTHOR]

Platinum-based nanocrystals are the most effective electrocatalysts for accelerating the chemical transformations on the anode in direct alcohol fuel cells. To facilitate practical applications and overcome the drawbacks of diverse alcohols, it is significant to develop electrocatalysts with high activities and a wide fuel flexibility. Here, we demonstrate a practicable solution method for fabricating composition tunable trimetallic PtNiRu dendritic nanostructures (DNSs) which can serve as versatile and active catalysts for electrooxidation of a variety of liquid alcohols. A series of trimetallic DNSs with tunable Pt/Ni/Ru atomic ratios were successfully synthesized by simply adjusting the feeding of precursors. Detailed electrochemical test indicates that, among other compositions, the Pt66Ni27Ru7 DNSs present much superior electroactivity in catalyzing electrooxidation of liquid alcohols in acidic mediums. Specifically, the mass activity and specific activity on the Pt66Ni27Ru7 DNSs, for electrooxidation of methanol, ethanol, and ethylene glycol, are 4.57 and 4.34 times, 3.55 and 3.42 times, and 2.37 and 2.28 times that of the commercial Pt black, respectively. X-ray photoelectron spectroscopy and CO stripping studies reveal the adsorption of CO on these PtNiRu DNSs is much weaker than on pure Pt. Meanwhile, the surface Ru sites can provide neighbouring-OH groups to facilitate the oxidation and removal of the adsorbed intermediates (-CO) on the surface Pt sites, effectively improving the CO tolerance of the catalysts. The PtNiRu DNSs also show effectively boosted capacity for breaking the C-C bond in C2-alcohols, showing great potential for fuel-flexible fuel cell applications. [ABSTRACT FROM AUTHOR]

Cardiac hypertrophy is classified as pathological and physiological hypertrophy. Pathological hypertrophy typically precedes the onset of heart failure, one of the largest contributors to disease burden and deaths worldwide. In contrast, physiological hypertrophy is an adaptive response and protects against adverse cardiac remodeling. Noncoding RNAs (ncRNAs) have drawn significant attention over the last couple of decades, and their dysregulation is increasingly being linked to cardiac hypertrophy and cardiovascular diseases. In this review, we will summarize the profiling, function, and molecular mechanism of microRNAs, long noncoding RNAs, and circular RNAs in pathological cardiac hypertrophy. Additionally, we also review microRNAs responsible for physiological hypertrophy. With better understanding of ncRNAs in cardiac hypertrophy, manipulation of the important ncRNAs will offer exciting avenues for the prevention and therapy of heart failure. [ABSTRACT FROM AUTHOR]

Based on an explicit representation of moments of hitting times for single death processes, the criteria on ergodicity and strong ergodicity are obtained. These results can be applied for an extended class of branching processes. Meanwhile, some sufficient and necessary conditions for recurrence and exponential ergodicity as well as extinction probability for the processes are presented. [ABSTRACT FROM AUTHOR]

Phase equilibria of the Al-Cu-Zn system on Al-Zn rich side was experimentally determined with 16 alloys annealed at 360 °C. The annealed alloys were examined by means of x-ray diffraction, electron probe microanalysis and differential scanning calorimetry. Five single-phase regions and seven two-phase regions as well as three three-phase regions, i.e. α-(Al) + θ-Al2Cu + τ′-Al4Cu3Zn, α-(Al) + τ′-Al4Cu3Zn + ε-CuZn4 and α-(Al) + ε-CuZn4 + (Zn), were determined. The partial isothermal section of the Al-Cu-Zn system on Al-Zn rich side at 360 °C was constructed based on the obtained experimental data in this work. It was observed that the solid solution phase α-(Al) would easily decompose into ε-CuZn4, (Zn) and α′-(Al) at the ambient temperature in the early stages. The ternary phase τ′-Al4Cu3Zn would form and ε-CuZn4 would disappear gradually along with the extension of aging time. [ABSTRACT FROM AUTHOR]

Extracellular vesicles (EVs) serve an important function as mediators of intercellular communication. Exercise is protective for the heart, although the signaling mechanisms that mediate this cardioprotection have not been fully elucidated. Here using nano-flow cytometry, we found a rapid increase in plasma EVs in human subjects undergoing exercise stress testing. We subsequently identified that serum EVs were increased by ~1.85-fold in mice after 3-week swimming. Intramyocardial injection of equivalent quantities of EVs from exercised mice and non-exercised controls provided similar protective effects against acute ischemia/reperfusion (I/R) injury in mice. However, injection of exercise-induced EVs in a quantity equivalent to the increase seen with exercise (1.85 swim group) significantly enhanced the protective effect. Similarly, treatment with exercise-induced increased EVs provided additional anti-apoptotic effect in HO-treated H9C2 cardiomyocytes mediated by the activation of ERK1/2 and HSP27 signaling. Finally, by treating H9C2 cells with insulin-like growth factor-1 to mimic exercise stimulus in vitro, we found an increased release of EVs from cardiomyocytes associated with ALIX and RAB35 activation. Collectively, our results show that exercise-induced increase in circulating EVs enhances the protective effects of endogenous EVs against cardiac I/R injury. Exercise-derived EVs might serve as a potent therapy for myocardial injury in the future. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) accounts for almost three quarters of dementia patients and interferes people's normal life. Great progress has been made recently in the study of Acetylcholinesterase (AChE), known as one of AD's biomarkers. In this study, acetylcholinesterase inhibitors (AChEI) were collected to build a two-dimensional structure-activity relationship (2D-SAR) model and three-dimensional quantitative structure-activity relationship (3D-QSAR) model based on feature selection method combined with random forest. After calculation, the prediction accuracy of the 2D-SAR model was 89.63% by using the tenfold cross-validation test and 87.27% for the independent test set. Three cutting ways were employed to build 3D-QSAR models. A model with the highest $${q}^{2}$$ (cross-validated correlation coefficient) and $${r}^{2 }$$ (non-cross-validated correlation coefficient) was obtained to predict AChEI activity. The mean absolute error (MAE) of the training set and the test set was 0.0689 and 0.5273, respectively. In addition, molecular docking was also employed to reveal that the ionization state of the compounds had an impact upon their interaction with AChE. Molecular docking results indicate that Ser124 might be one of the active site residues. [ABSTRACT FROM AUTHOR]

We obtain sufficient criteria for central limit theorems (CLTs) for ergodic continuous-time Markov chains (CTMCs). We apply the results to establish CLTs for continuous-time single birth processes. Moreover, we present an explicit expression of the time average variance constant for a single birth process whenever a CLT exists. Several examples are given to illustrate these results. [ABSTRACT FROM AUTHOR]

The mixed principal eigenvalue of p -Laplacian (equivalently, the optimal constant of weighted Hardy inequality in L space) is studied in this paper. Several variational formulas for the eigenvalue are presented. As applications of the formulas, a criterion for the positivity of the eigenvalue is obtained. Furthermore, an approximating procedure and some explicit estimates are presented case by case. An example is included to illustrate the power of the results of the paper. [ABSTRACT FROM AUTHOR]

This paper deals with the principal eigenvalue of discrete p-Laplacian on the set of nonnegative integers. Alternatively, it is studying the optimal constant of a class of weighted Hardy inequalities. The main goal is the quantitative estimates of the eigenvalue. The paper begins with the case having reflecting boundary at origin and absorbing boundary at infinity. Several variational formulas are presented in different formulation: the difference form, the single summation form, and the double summation form. As their applications, some explicit lower and upper estimates, a criterion for positivity (which was known years ago), as well as an approximating procedure for the eigenvalue are obtained. Similarly, the dual case having absorbing boundary at origin and reflecting boundary at infinity is also studied. Two examples are presented at the end of Section 2 to illustrate the value of the investigation. [ABSTRACT FROM AUTHOR]

Based on a new explicit representation of the solution to the Poisson equation with respect to single birth processes, the unified treatment for various criteria on classical problems (including uniqueness, recurrence, ergodicity, exponential ergodicity, strong ergodicity, as well as extinction probability, etc.) for the processes are presented. [ABSTRACT FROM AUTHOR]

The criteria on separation cutoff for birth and death chains were obtained by Diaconis and Saloff-Coste in 2006. These criteria are involving all eigenvalues. In this paper, we obtain the explicit criterion, which depends only on the birth and death rates. Furthermore, we present two ways to estimate moments of the fastest strong stationary time and then give another but equivalent criterion explicitly. [ABSTRACT FROM AUTHOR]

In this paper, we synthesized cathode catalysts (PANI-PPYR, Fe/PANI-PPYR, Co/PANI-PPYR and Fe-Co/PANI-PPYR) with high performance oxygen reduction by using a simple heat treatment process. These catalysts were fabricated by directly calcining the Fe and/or Co doped polyaniline (PANI)-polypyrrole (PPYR) composites. Their electrocatalytic activity for ORR both in acidic and in alkaline media was investigated by voltammetric techniques. Among the prepared catalysts, Co/PANI-PPYR presents the most positive ORR onset potential of 0.62 V (vs. SCE) in 0.5 mol/L HSO solution or −0.09 V (vs. SCE) in 1 mol/L NaOH solution. In addition, the Co/PANI-PPYR catalyst shows the largest limiting-diffusion current density for ORR, which is 4.3 mA/cm@0.2 V (vs. SCE) in acidic and 2.3 mA/cm@−0.3 V (vs. SCE) in alkaline media. In acidic media, a four-electron reaction of ORR on the Co/PANI-PPYR and Fe/PANI-PPYR catalysts is more dominant than a two-electron reaction. In alkaline media, however, a four-electron and a two-electron mechanisms are co-present for the ORR on all the prepared catalysts. Co/PANI-PPYR catalyst also presents good electrocatalytic activity stability for ORR both in acidic and in alkaline media. [ABSTRACT FROM AUTHOR]

Development of precious metal-free catalysts for oxygen reduction reaction (ORR) is of great significance for the practical application of fuel cells. In this article, we report the finding that the C–N composites containing Fe and/or Co (C–PANI, Fe/C–PANI, Co/C–PANI, and FeCo/C–PANI), produced by directly pyrolyzing the Fe- and/or Co-doped polyaniline (PANI) precursors, show efficient electroactivity for ORR both in acidic and in alkaline media. Among the prepared catalysts, Fe/C–PANI and Co/C–PANI present the most positive ORR onset potential that is 0.61 V (vs. SCE) in 0.5 mol L −1 H 2SO 4 solution or −0.1 V (vs. SCE) in 1 mol L −1 NaOH solution. In addition, the Fe/C–PANI catalyst shows the largest limiting-diffusion current density for ORR both in acidic and in alkaline media. A four-electron reaction of ORR on the Fe/C–PANI and Co/C–PANI catalysts is more dominant than a two-electron reaction. Fe/C–PANI catalyst also presents good electrocatalytic activity stability for ORR both in acidic and in alkaline media. [ABSTRACT FROM AUTHOR]

In 2002, the Research Center for Stochastics started to organize "Workshop on Markov Processes and Related Topics". China 2021, 16(2): 255{256 https://doi.org/10.1007/s11464-021-0924-7 Markov Processes and Related Topics (III) Wenming HONG, Yonghua MAO, Yuhui ZHANG Research Center for Stochastics; School of Mathematical Sciences, Beijing Normal University, Beijing 100875, China c Higher Education Press 2021 It is our great pleasure to present the third special issue for the Markov Processes and Related Topics, on the occasion of the 20th anniversary of the Research Center for Stochastics of Beijing Normal University (BNU), supported by the innovative research group project of the National Natural Science Foundation of China. 1) 2002, 2) 2004, 3) 2005, 5) 2007, 7) 2010, at BNU; 4) 2006, BNU and Central South University, Changsha; 6) 2008, BNU and Anhui Normal University, Wuhu; 8) 2012, BNU and Fujian Normal University, Wuyi Mountain; 9) 2013, BNU and Southwest Jiaotong University, Emei; 10) 2014, BNU and Xidian University, Xi'an; 11) 2015, BNU and Shanghai Jiaotong University, Shanghai; 12) 2016, BNU and Jiangsu Normal University, Xuzhou; 13) 2017, BNU and Wuhan University, Wuhan; 14) 2018, BNU and Sichuan University, Chengdu; 15) 2019, BNU and Jilin University, Changchun; 16) 2021, BNU and Central South University, Changsha. [Extracted from the article]

This is one of a series of papers exploring the stability speed of one-dimensional stochastic processes. The present paper emphasizes on the principal eigenvalues of elliptic operators. The eigenvalue is just the best constant in the L-Poincaré inequality and describes the decay rate of the corresponding diffusion process. We present some variational formulas for the mixed principal eigenvalues of the operators. As applications of these formulas, we obtain case by case explicit estimates, a criterion for positivity, and an approximating procedure for the eigenvalue. [ABSTRACT FROM AUTHOR]

Aggression in socially monogamous mandarin vole ( Microtus mandarinus) was observed after castration. Levels of serum sex hormones and their central receptors were also measured using enzyme-linked immunosorbent assay and immunohistochemistry methods. The data indicate that adult males showed higher levels of aggression after castration. However, castration significantly reduced levels of serum testosterone, and the number of androgen receptor immunoreactive neurons in the anterior hypothalamus, bed nucleus of the stria terminalis, medial amygdaloid nucleus ( P < 0.01) and lateral septal nucleus ( P < 0.05). In addition, levels of estrogen receptor β in the anterior hypothalamus and medial amygdaloid nucleus ( P < 0.05), bed nucleus of the stria terminalis and lateral septal nucleus ( P < 0.01) declined to varying degrees at weekly intervals. In contrast, serum 17β-estradiol concentrations were up-regulated by castration and castration did not change levels of estrogen receptor α in the medial amygdaloid nucleus and lateral septal nucleus, but increased it in the anterior hypothalamus 3 weeks after castration ( P < 0.05). We suggest that higher levels of aggression induced by castration may be independent of serum testosterone and androgen receptors, and may be associated with high serum 17β-estradiol concentrations, stable estrogen receptor α immunoreactive neurons in some brain regions and the relative ratio of the two estrogen receptors. [ABSTRACT FROM AUTHOR]

Amphipathic polymer pullulan acetate (PA)-coated magnetic nanoparticles were prepared and characterized by various physicochemical means. The cytotoxicity and cellular uptake of the magnetic nanoparticles were examined. The hyperthermic effect of the magnetic nanoparticles on tumor cells was evaluated. Transmission electron microscopy (TEM) showed that the PA coated magnetic nanoparticles (PAMNs) had spherical morphology. Dynamic light scattering (DLS) showed that the size distribution of PAMNs was unimodal,with an average diameter of 25.8 nm ± 6.1 nm. The presence of the adsorbed layer of PA on the magnetite surface was confirmed by Fourier transform infrared (FTIR) spectroscopy. Magnetic measurements revealed that the saturation magnetization of the PAMNs reached 51.9 emu/g and the nanoparticles were superparamagnetic. Thermogravimetric analysis (TGA) showed that the Fe3O4 particles constituted 75 wt% of the PAMNs. The PAMNs had good heating properties in an alternating magnetic field. Cytotoxicity assay showed that PAMNs exhibited no significant cytotoxicity against L929 cells. TEM results showed that a large number of PAMNs were internalized into KB cells. PAMNs have good hyperthermia effect on KB cells in vitro by magnetic field induced hyperthermia. These novel magnetic nanoparticles have great potential as magnetic hyperthermia mediators. [ABSTRACT FROM AUTHOR]

The aim of the paper is to establish two dual variational formulas for the first Dirichlet eigenvalue of the second order elliptic operators on half-line. Some explicit bounds of the eigenvalue depending only on the coefficients of the operators are presented. Moreover, the corresponding problems in the discrete case and the higher-order eigenvalues in the continuous case are also studied. [ABSTRACT FROM AUTHOR]

Abstract This note is devoted to the study of the stochastic comparability of jump processes. On the basis of [2] and [3], it is proved that two jump processes are stochastically comparable if and only if their q-pairs are comparable. Meanwhile, the result concerning the uniqueness given in [6] is also improved upon. [ABSTRACT FROM AUTHOR]