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Objective: To extract texture features from vocal cord leukoplakia (VCL) images and establish a VCL risk stratification prediction model using machine learning (ML) techniques. Methods: A total of 462 patients with pathologically confirmed VCL were retrospectively collected and divided into low‐risk and high‐risk groups. We use a 5‐fold cross validation method to ensure the generalization ability of the model built using the included dataset and avoid overfitting. Totally 504 texture features were extracted from each laryngoscope image. After feature selection, 10 ML classifiers were utilized to construct the model. The SHapley Additive exPlanations (SHAP) was employed for feature analysis. To evaluate the model, accuracy, sensitivity, specificity, and the area under the receiver operating characteristic (ROC) curve (AUC) were utilized. In addition, the model was transformed into an online application for public use and further tested in an independent dataset with 52 cases of VCL. Results: A total of 12 features were finally selected, random forest (RF) achieved the best model performance, the mean accuracy, sensitivity, specificity, and AUC of the 5‐fold cross validation were 92.2 ± 4.1%, 95.6 ± 4.0%, 85.8 ± 5.8%, and 90.7 ± 4.9%, respectively. The result is much higher than the clinicians (AUC between 63.1% and 75.2%). The SHAP algorithm ranks the importance of 12 texture features to the model. The test results of the additional independent datasets were 92.3%, 95.7%, 90.0%, and 93.3%, respectively. Conclusion: The proposed VCL risk stratification prediction model, which has been developed into a public online prediction platform, may be applied in practical clinical work. Level of Evidence: 3 Laryngoscope, 134:4329–4337, 2024 [ABSTRACT FROM AUTHOR]

The oxide scale on the surface of hot‐rolled low‐carbon steel strips is subjected to isothermal reduction in 10 vol%H2–Ar and 20 vol%H2–Ar environments to simulate the reduction process that occurs in a continuous annealing furnace. The influence of hydrogen concentration on the reduction kinetics and the microstructural evolution of the oxide scale after reduction at temperatures ranging from 450 to 850 °C for a duration of 20 min are investigated in detail. The mass changes of the oxide scale in the two gases are quantified using a thermogravimetric analyzer. This data is then employed to calculate the reduction rate constant and the apparent activation energy. To examine the microstructure and element distribution, electron probe microanalysis and energy‐dispersive spectrometry are employed. An novel approach is also undertaken to assess the reduction degree of the oxide scale by measuring surface microhardness. In the findings, it is indicated that an increase in hydrogen concentration served primarily to accelerate the reduction reaction within the temperature ranges of 450–550 and 800–850 °C. Meanwhile, the mechanism of physical transformation of oxide scale, the microstructure of reduction layer, and hydrogen concentration on reduction efficiency under different reaction stages are proposed. [ABSTRACT FROM AUTHOR]

The precipitation, growth, and transformation of carbides rich in Cr and Mo during solidification and cooling process of high‐alloy steel for cold working dies are investigated. The Fe–C pseudobinary phase diagram of high‐alloy steel is calculated by Thermo‐Calc software to ascertain the critical phase transformation temperatures. The temperatures of phase transformation during the solidification process are determined by a differential scanning calorimeter. Then the microstructure of the samples at these characteristic temperatures is observed in situ by high‐temperature confocal microscope. The results show that the characteristic temperatures for phase transformation and carbide precipitation are 1380, 1315, 1140, and 980 °C, respectively. At 1315 °C, thick rod‐like or island‐like M7C3 carbides enriched in Cr and Fe are formed. At 1140 °C, secondary M7C3, adhering to the primary eutectic M7C3, grows rapidly in a rod‐like morphology and maintains a similar composition. The secondary M6C carbides of segregated Mo elements precipitate in fan‐shaped clusters near M7C3 through the dissolution of M7C3 and the conversion of M2C. Thermodynamic calculation further indicates that the eutectic Cr7C3 precipitates at 1213 °C, and secondary Cr7C3 remains under conditions favorable for precipitation below the solidus, preceding the precipitation of secondary carbides Cr23C6 and Mo2C. [ABSTRACT FROM AUTHOR]

Background: Chronic heart failure (CHF) has always posed a significant threat to human survival and health. The efficacy of thiamine supplementation in CHF patients remains uncertain. Hypothesis: Receiving supplementary thiamine may not confer benefits to patients with CHF. Methods: A comprehensive search was conducted across the Cochrane Library, PubMed, EMBASE, ClinicalTrials.gov, and Web of Science databases up until May 2023 to identify articles investigating the effects of thiamine supplementation in CHF patients. Predefined criteria were utilized for selecting data on study characteristics and results. Results: Seven randomized, double‐blind, controlled trials (five parallel trials and two crossover trials) involving a total of 274 patients were enrolled. The results of the meta‐analysis pooling these studies did not reveal any significant effect of thiamine treatment compared with placebo on left ventricular ejection fraction (WMD = 1.653%, 95% CI: −1.098 to 4.405, p = 0.239, I2 = 61.8%), left ventricular end‐diastolic volume (WMD = −6.831 mL, 95% CI: −26.367 to 12.704, p = 0.493, I2 = 0.0%), 6‐min walking test (WMD = 16.526 m, 95% CI: −36.582 to 69.634, p = 0.542, I2 = 66.3%), N‐terminal pro‐B type natriuretic peptide (WMD = 258.150 pg/mL, 95% CI: −236.406 to 752.707, p = 0.306, I2 = 21.6%), or New York Heart Association class (WMD = −0.223, 95% CI: −0.781 to 0.335, p = 0.434, I2 = 87.1%). However, it effectively improved the status of thiamine deficiency (TD). Conclusions: Our meta‐analysis indicates that thiamine supplementation does not have a direct therapeutic effect on CHF, except for correcting TD. [ABSTRACT FROM AUTHOR]

Uncovering the immune response to an inactivated SARS‐CoV‐2 vaccine (In‐Vac) and natural infection is crucial for comprehending COVID‐19 immunology. Here we conducted an integrated analysis of single‐cell RNA sequencing (scRNA‐seq) data from serial peripheral blood mononuclear cell (PBMC) samples derived from 12 individuals receiving In‐Vac compared with those from COVID‐19 patients. Our study reveals that In‐Vac induces subtle immunological changes in PBMC, including cell proportions and transcriptomes, compared with profound changes for natural infection. In‐Vac modestly upregulates IFN‐α but downregulates NF‐κB pathways, while natural infection triggers hyperactive IFN‐α and NF‐κB pathways. Both In‐Vac and natural infection alter T/B cell receptor repertoires, but COVID‐19 has more significant change in preferential VJ gene, indicating a vigorous immune response. Our study reveals distinct patterns of cellular communications, including a selective activation of IL‐15RA/IL‐15 receptor pathway after In‐Vac boost, suggesting its potential role in enhancing In‐Vac‐induced immunity. Collectively, our study illuminates multifaceted immune responses to In‐Vac and natural infection, providing insights for optimizing SARS‐CoV‐2 vaccine efficacy. [ABSTRACT FROM AUTHOR]

A regioselective synthesis of isoxazoles with propargyl alcohols, N‐iodosuccinimide (NIS), and N‐tert‐butyl hydroxylamine hydrochloride (t‐BuNHOH•HCl) as the reaction substrates is reported. Reaction scope investigations indicated that primary and secondary propargyl alcohols underwent this transformation smoothly to afford 5‐, 3‐, and 3,5‐substituted isoxazoles in moderate to good yields. The reaction most likely involves an electrophilic‐intercepted Meyer‐Schuster rearrangement of the propargyl alcohol, followed by intermolecular cyclocondensation of N‐tert‐butyl hydroxylamine and in‐situ‐formed α‐iodo enones/enals. This one‐pot method is regioselective and easy to perform, making it a valuable method for the construction of isoxazoles. Finally, its application was explored through the synthesis of valdecoxib. [ABSTRACT FROM AUTHOR]

Extranodal natural killer/T‐cell lymphoma (NKTCL) is an aggressive type of lymphoma associated with Epstein–Barr virus (EBV) and characterized by heterogeneous tumor behaviors. To better understand the origins of the heterogeneity, this study utilizes single‐cell RNA sequencing (scRNA‐seq) analysis to profile the tumor microenvironment (TME) of NKTCL at the single‐cell level. Together with in vitro and in vivo models, the study identifies a subset of LMP1+ malignant NK cells contributing to the tumorigenesis and development of heterogeneous malignant cells in NKTCL. Furthermore, malignant NK cells interact with various immunocytes via chemokines and their receptors, secrete substantial DPP4 that impairs the chemotaxis of immunocytes and regulates their infiltration. They also exhibit an immunosuppressive effect on T cells, which is further boosted by LMP1. Moreover, high transcription of EBV‐encoded genes and low infiltration of tumor‐associated macrophages (TAMs) are favorable prognostic indicators for NKTCL in multiple patient cohorts. This study for the first time deciphers the heterogeneous composition of NKTCL TME at single‐cell resolution, highlighting the crucial role of malignant NK cells with EBV‐encoded LMP1 in reshaping the cellular landscape and fostering an immunosuppressive microenvironment. These findings provide insights into understanding the pathogenic mechanisms of NKTCL and developing novel therapeutic strategies against NKTCL. [ABSTRACT FROM AUTHOR]

Using multi‐task learning to extract code features can effectively increase the information of the features. However, the existing multi‐task learning methods mainly have two limitations: (1) They cannot extract enough code‐related information or only extract similar semantic features. Similar multi‐task makes the information in the features increased insufficiently. However, the high difference multi‐task is challenging to converge. (2) They cannot train multi‐task on heterogeneous datasets. In standard multi‐task training, we need to label all tasks for all data, which consumes enormous labor. To solve the above limitations, we select two high difference tasks, the cross‐language code completion task and variable misuse task, to extract expressive semantic code features. We propose an attention‐based feature fusion module to merge information among high difference tasks, avoiding the convergence dilemma of standard multi‐task learning. We propose a federated learning framework, extracting semantic information and using the feature fusion module to integrate multi‐task information among single labeled datasets. We experiment on C# and Python datasets for the code completion and variable misuse tasks. The results show that the performance of fusion features by FedMTFF improved by up to 22.6% and 15.1% compared to single tasks. We use FedMTFF to perform four cross‐language multi‐task features fusion, exceeding the current best baseline by 24.1%. [ABSTRACT FROM AUTHOR]

Background: Congenital shunt location is related to Eisenmenger syndrome (ES) survival. Moreover, right ventricular (RV) remodeling is associated with poor survival in pulmonary hypertension. Purpose: To investigate RV remodeling using comprehensive magnetic resonance imaging (MRI) techniques and identify its relationship with prognosis in ES subgroups classified by shunt location. Study Type: Prospective observational study. Population: Fifty‐four adults with ES (16 with pre‐tricuspid shunt and 38 with post‐tricuspid shunt). Field Strength/Sequence: 3.0 T/cine MRI with balanced steady‐state free precession sequence, late gadolinium enhancement with inversion recovery segmented gradient echo sequence and phase‐sensitive reconstruction, and T1 mapping with modified Look‐Locker inversion recovery sequence. Assessment: Demographics, clinical characteristics, hemodynamics, RV remodeling features (morphology, systolic function, RV–pulmonary artery (PA) coupling and myocardial fibrosis), and prognosis were compared between ES subgroups. The adverse endpoint was all‐cause mortality or readmission for heart failure. Statistical Tests: The independent samples t‐test, Fisher's exact test or Chi‐squared test, and the Kaplan–Meier method were used. P < 0.05 was considered significant. Results: Compared to patients with post‐tricuspid shunt, patients with pre‐tricuspid shunt were significantly older and had higher N‐terminal pro‐B‐type natriuretic peptide concentrations and poorer exercise tolerance. Pre‐tricuspid shunt showed significantly larger RV dimensions (end‐diastolic volume index: 185.81 ± 37.49 vs. 98.20 ± 36.26 mL/m2), worse RV ejection fraction (23.54% ± 12.35% vs. 40.82% ± 10.77%), and RV–PA decoupling (0.35 ± 0.31 vs. 0.72 ± 0.29). Biventricular myocardial fibrosis was significantly more severe in pre‐tricuspid shunt than post‐tricuspid shunt (extracellular volume, left ventricle: 35.85% ± 2.58% vs. 29.10% ± 5.20%; RV free wall: 30.93% ± 5.65% vs. 26.75% ± 5.15%). In addition, pre‐tricuspid shunt demonstrated a significantly increased risk of adverse endpoint (hazard ratio: 2.938, 95% confidence interval: 1.204–7.172). Data Conclusion: ES with pre‐tricuspid shunt might be a unique subtype with worse clinically decompensated RV remodeling and poor prognosis. Level of Evidence: 2 Technical Efficacy Stage: 5 [ABSTRACT FROM AUTHOR]

Smad4, a key mediator of the transforming growth factor‐β signaling, is mutated or deleted in 20% of pancreatic ductal adenocarcinoma (PDAC) cancers and significantly affects cancer development. However, the effect of Smad4 loss on the immunogenicity and tumor immune microenvironment of PDAC is still unclear. Here, a surprising function of Smad4 in suppressing mouse PDAC tumor immunogenicity is identified. Although Smad4 deletion in tumor cells enhances proliferation in vitro, the in vivo growth of Smad4‐deficient PDAC tumor is significantly inhibited on immunocompetent C57BL/6 (B6) mice, but not on immunodeficient mice or CD8+ cell‐depleted B6 mice. Mechanistically, Smad4 deficiency significantly increases tumor cell immunogenicity by promoting spontaneous DNA damage and stimulating STING‐mediated type I interferon signaling,which contributes to the activation of type 1 conventional dendritic cells (cDC1) and subsequent CD8+ T cells for tumor control. Furthermore, retarded tumor growth of Smad4‐deficient PDAC cells on B6 mice is largely reversed when Sting is codeleted, or when the cells are implanted into interferon‐alpha receptor‐deficientmice or cDC1‐deficientmice. Accordingly, Smad4 deficiency promotes PDAC immunogenicity by inducing tumor‐intrinsic DNA damage‐elicited type I interferon signaling. [ABSTRACT FROM AUTHOR]

20–30% of patients with nasopharyngeal carcinoma (NPC) develop distant metastasis or recurrence leading to poor survival, of which the underlying key molecular events have yet to be addressed. Here alternative splicing events in 85 NPC samples are profiled using transcriptome analysis and it is revealed that the long isoform of GOLIM4 (‐L) with exon‐7 is highly expressed in NPC and associated with poor prognosis. Lines of evidence demonstrate the pro‐tumorigenic function of GOLIM4‐L in NPC cells. It is further revealed that RBFOX2 binds to a GGAA motif in exon‐7 and promotes its inclusion forming GOLIM4‐L. RBFOX2 knockdown suppresses the tumorigenesis of NPC cells, phenocopying GOLIM4‐L knockdown, which is significantly rescued by GOLIM4‐L overexpression. High expression of RBFOX2 is correlated with the exon‐7 inclusion of GOLIM4 in NPC biopsies and associated with worse prognosis. It is observed that RBFOX2 and GOLIM4 can influence vesicle‐mediated transport through maintaining the organization of Golgi apparatus. Finally, it is revealed that RAB26 interacts with GOLIM4 and mediates its tumorigenic potentials in NPC cells. Taken together, the findings provide insights into how alternative splicing contributes to NPC development, by highlighting a functional link between GOLIM4‐L and its splicing regulator RBFOX2 activating vesicle‐mediated transport involving RAB26. [ABSTRACT FROM AUTHOR]

The uniaxial hot compression tests of Cr8Mo2SiV tool steel are conducted by thermomechanical simulator in a wide strain rate range of 0.005–5 s−1 and temperature range of 900–1150 °C to predict the hot deformation behavior. It is found that flow stress strongly depends on deformation temperature and strain rate under the mechanisms of dynamic softening and work hardening. Second, the Johnson–Cook model and modified Arrhenius‐type equation considering the compensation of strain are proposed for the estimation of flow stress of the tool steel. Subsequently, the validity of the established constitutive models is verified by standard statistical parameters including correlation coefficient (R) and average absolute relative error (AARE). Finally, the hot deformed microstructure is analyzed using the constitutive model with strong predictive ability. With the decrease in lnZ (Z is the Zener–Hollomon [Z–H] parameter) value from 43.5 to 32.7 s−1, microstructure evolution indicates that a remarkable increase in the high‐angle grain boundaries (misorientation more than 15°) from 19.1% to 32.6%, which also reflects the reliability of Z–H map in predicting dynamic recrystallization behavior under most thermal deformation conditions. [ABSTRACT FROM AUTHOR]

Super broadband near‐infrared (NIR) phosphor converted light‐emitting diodes (pc‐LEDs) are future light sources in NIR spectroscopy applications such as food testing. At present, a few blue LED excitable super broadband NIR phosphors (bandwidth > 300 nm) have been developed producing the NIR output powers below 26 mW at 100 mA input current after LED packaging. Here, an efficient super broadband NIR phosphor achieved by doping Yb3+ is reported in the NIR Ca2LuZr2Al3O12:Cr3+ (CLZA:Cr3+) garnet phosphor developed previously. Benefited from the superposition of Cr3+ emission and highly efficient Yb3+ emission excited by energy transfer from Cr3+, the codoped CLZA:Cr3+,Yb3+ phosphor shows a bandwidth of 320 nm and an internal quantum efficiency of 77.2% both higher than that (150 nm and 69.1%) of singly doped CLZA:Cr3+ phosphor. The codoped phosphor converts LED produced 41.8 mW NIR output at 100 mA input current. The pc‐LED as a light source is also well applied to the NIR transmission spectra measurement of water. The results indicate the great potential of CLZA:Cr3+,Yb3+ phosphor in super broadband NIR pc‐LED applications. [ABSTRACT FROM AUTHOR]

Objectives/hypothesis: To analyze the epidemiological characteristics, clinical features, and the outcomes of histopathology and microbiology for fungus ball (FB) in the last 10 years in our department.Study Design: Database review.Methods: In total, 1,717 cases of FB were reviewed from the case database of Beijing Tongren Hospital (between 2008 and 2017). Epidemiologic data, clinical manifestations, histopathology, and microbiology were analyzed.Results: In the past 10 years, there has been a significant increase in patients with FB presenting at our department (P < .05). The mean age of patients with paranasal sinus FB was 54 years, and 67% of patients were female (1,156/1,717). The average age and female predominance were consistent with previous reports. In total, 1,626 cases (94.7%) were unilateral, and the most common location was the maxillary sinus (76.6%). Aspergillus spp. (72.8%) was the most abundant fungal species in our study. The direct smear positive rate was 68.6%, and the fungal culture rate was 22.6%. All cases were treated with functional endoscopic sinus surgery, with a very low rate of postoperative complications and reoperation (20/1,717).Conclusions: Histopathological and microbiological analyses are essential for the diagnosis of FB. Surgery is the most effective method of treatment. Direct smear after surgery is not necessary. Oral or topical antimycotic treatments are not recommended after surgery or during the perioperative period.Level Of Evidence: 4 Laryngoscope, 130:75-79, 2020. [ABSTRACT FROM AUTHOR]

A metal‐free visible‐light‐induced cyclization procedure was developed for the rapid synthesis of perfluoroalkyl‐substituted benzimidazo[2,1‐a]isoquinolin‐6(5H)‐ones and perfluoroalkyl‐substituted indolo[2,1‐a]isoquinolin‐6(5H)‐ones under mild reaction conditions. In this procedure, the formation of electron‐donor‐acceptor (EDA) complex is critical for the visible‐light promoted process to avoid the utilization of external photocatalysts. [ABSTRACT FROM AUTHOR]

Bola‐type quaternary ammonium salt can bridge with two fatty acid soaps through electrostatic attraction to form a pseudogemini surfactant, which enhances the solution viscosity. In this work, the effects of the building blocks (spacer and hydrophobic chain) of a pseudogemini surfactant on the Krafft temperature, critical micelle concentration, and rheological properties were investigated. The results revealed that the addition of bola‐type salt obviously decreased the Krafft temperature of sodium stearate (C18ONa), and a bola‐type salt bearing a large benzene ring (Bola2be) was more effective than the one bearing an ethyl group (Bola2et) or a hydroxyethyl group (Bola2hy). When bola‐type salt is mixed with fatty acid soap at a fixed molar ratio of 1:2, a pseudogemini surfactant forms in situ, and the viscosity of the solution is significantly enhanced by the formation of a worm‐like micelle (WLM) network. The stronger the hydrophobicity of the bola‐type salt or the tail of the fatty acid soap, the lower the critical overlapping and micelle concentrations, and the stronger is the ability to enhance viscosity. However, pseudogemini surfactants that use sodium stearate as a monomer show similar self‐assembly abilities to those using sodium oleate as a monomer. In addition, the WLM formed by pseudogemini surfactants composed of Bola2be and sodium stearate or sodium oleate were liable to branch at high concentrations. [ABSTRACT FROM AUTHOR]

A iron‐catalyzed free radical cascade reaction of allyl alcohols with N‐substituted maleimides for accessing poly‐substituted γ‐butyrolactones has been developed. In this protocol, various allyl alcohols can open N‐substituted maleimide rings to form allyl ester intermediates, and the allyl ester intermediates can be converted into an allyl ester alkyl radicals and undergo intramolecular free radical addition cyclization to form a polysubstituted γ‐butyrolactones. In this protocol, spiro γ‐butyrolactone compounds can be also synthesized. Meanwhile, the strategy could be applied to further construct a fully substituted tetrahydrofuran. The reaction is not sensitive to oxygen or moisture and has been performed on gram‐scale. [ABSTRACT FROM AUTHOR]

Bimetallic atomically dispersed FeNi catalysts anchored on N‐doped carbon nanotube with catalyst loading of 2–7 wt % with different Fe : Ni ratio have been developed as highly active and stable bifunctional catalyst for reversible oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) for metal air batteries via a modified one‐pot synthesis method. Compared with atomically dispersed single Fe and Ni catalysts, the bimetallic FeNi catalysts exhibit outstanding performance for reversible OER and ORR, achieving a low potential gap (ΔE) of 0.81 V to deliver an OER current density of 10 mA cm−2 and an ORR current density of 3 mA cm−2. The FeNi electrodes also show a much better stability in the cyclic tests, compared to that of the state‐of‐the‐art Pt/C and Pt/C+Ir/C electrodes for reversible OER and ORR. The high performance is likely due to the significantly enhanced OER activity contributed by the introduction of Ni atoms, forming bridged FeNi bimetallic dual atom active sites for OER. This study provides a new platform for the development of highly active bimetallic atomic catalysts based bifunctional electrocatalysts for metal‐air batteries. The modified one‐pot synthesis methods demonstrated in this study can also be applicable to other atomically dispersed catalysts on CNTs or graphenes. [ABSTRACT FROM AUTHOR]

Plasmon‐mediated carrier transfer (PMCT) at metal–semiconductor heterojunctions has been extensively exploited to drive photochemical reactions, offering intriguing opportunities for solar photocatalysis. However, to date, most studies have been conducted using noble metals. Inexpensive materials capable of generating and transferring hot carriers for photocatalysis via PMCT have been rarely explored. Here, we demonstrate that the plasmon excitation of nickel induces the transfer of both hot electrons and holes from Ni to TiO2 in a rationally designed Ni–TiO2 heterostructure. Furthermore, it is discovered that the transferred hot electrons either occupy oxygen vacancies (VO) or produce Ti3+ on TiO2, while the transferred hot holes are located on surface oxygens at TiO2. Moreover, the transferred hot electrons are identified to play a primary role in driving the degradation of methylene blue (MB). Taken together, our results validate Ni as a promising low‐cost plasmonic material for prompting visible‐light photochemical reactions. [ABSTRACT FROM AUTHOR]

Fluorine has been recognized to selectively stabilize anatase titanium dioxide (TiO2) crystal facets; however, resolving its physical location at the nanometer scale remains empirically elusive. Here, we provide direct experimental evidence to reveal the spatial distribution of fluorine on single truncated anatase bipyramids (TABs) using nanoscale secondary ion mass spectrometry (NanoSIMS). Fluorine was found to preferentially adsorb on the (001) facet compared to the (101) facet of TABs. Moreover, NanoSIMS depth profiling exhibited a significantly different fluorine distribution between these two facets in the near‐surface region, illustrating the essential role of lattice‐doped fluorine in the anisotropic crystal growth of TABs. The interaction of surface fluorine with truncated anatase bipyramid (TAB) facets at the single‐particle level is reported; more importantly, this work illustrates the essential role of lattice fluorine doping in the anisotropic growth of TABs (see picture). [ABSTRACT FROM AUTHOR]

The effect of different homogenization parameters on the microstructure and element distribution of Cr8Mo2SiV cold‐work die steel ingot is investigated. Based on the Thermo‐Calc software and laser confocal microscopy, the optimal heat treatment temperature range from 1160 to 1230 °C is obtained for experimental steel. In order to improve dendritic segregation of as‐cast microstructure consisting of a large number of network eutectic carbides enriched in alloying elements, the homogenization treatment is carried out at the above determined temperatures for 0.5, 1, and 3 h, respectively. Then, according to the segregation ratio of Cr element, the homogenization at 1180 °C for 3 h successfully eliminates the microsegregation, which is in agreement with the calculation of the diffusion kinetic model of Cr element. [ABSTRACT FROM AUTHOR]

Abstract: (100)C‐oriented Na0.5Bi0.5‐xSmxTiO3 (NBST) lead‐free ferroelectric thin films were prepared on Pt/Ti/SiO2/Si substrates by chemical solution deposition method, and their microstructural, dielectric, ferroelectric, and photoluminescent properties were studied. X‐ray diffraction and scanning electron microscopy analysis indicated that both the grain size and (100)C orientation degree of NBST thin films were decreased by doping Sm3+ ions. Raman spectra showed that structural symmetry of NBST thin films decreased at low Sm3+ doping concentration and then increased at high doping concentration of Sm3+ ions. An appropriate amount of Sm3+ dopants was confirmed to enhance dielectric and ferroelectric properties of the NBST thin films. Among all the compositions, the Na0.5Bi0.492Sm0.008TiO3 thin film exhibited the largest remnant polarization (2Pr) of 27.3 μC/cm2 and high dielectric constant of 1068, as well as a low dielectric loss of 0.04. Temperature‐ and frequency‐dependent dielectric characteristics illustrated the relaxor ferroelectric behavior of Na0.5Bi0.492Sm0.008TiO3 thin film. Meanwhile, the Na0.5Bi0.492Sm0.008TiO3 thin film also showed optimal orange‐red emission at 600 nm, which is originating from the 4G5/2 → 4H7/2 transition of Sm3+ ions. [ABSTRACT FROM AUTHOR]

Abstract: Using light irradiation to manipulate magnetization over a prolonged period of time offers a wealth of opportunities for spin‐based electronics and photonics. To date, persistent photomagnetism has been frequently reported in spin systems composed of molecular magnets; yet this phenomenon is rarely observed in nanoparticle‐based systems comprised of transition metal oxides. Here, detailed studies of persistent photomagnetism in superparamagnetic iron oxide (Fe3O4) nanoparticles at temperatures below their blocking temperature are presented and it is demonstrated that the magnetization change does not occur through steady‐state spin transitions or photothermal heating. Instead, it is found that exciton–spin exchange‐coupling plays a critical role in modulating the magnetization by lowering the anisotropic energy barrier of Fe3O4 nanoparticles to facilitate their optically driven conversion from ferrimagnetic to superparamagnetic. Collectively, these insights establish a comprehensive understanding of the underlying photophysical processes that regulate photomagnetism in nanoparticle‐based magnetic systems composed of transition metal oxides. [ABSTRACT FROM AUTHOR]

In this research a type of wood plastic composites (TRWPCs) is prepared by blending tea residue (TR) with high-density polyethylene (HDPE). The chemical composition of TR was analyzed quantitatively. The effects of TR content, compatibilizers, and nanofillers on the structure, morphology, and mechanical properties were studied. The results showed that the stiffness of TR-WPCs was significantly improved with the increase in TR, while the strength and toughness decreased. Scanning electron microscope indicated that the maleic anhydride grafted polyethylene as compatibilizer enhanced interface adhesion of the composites; Thermo-gravimetric analysis and Vicat test showed that the composite made with the nanofiller could improve the heat stability and heat resistance. Differential scanning calorimetry indicated that the addition of inorganic fillers slightly influenced the crystallization behavior of the HDPE matrix. The TR with boiling water treatment could significantly improve the mechanical properties of the composites. [ABSTRACT FROM AUTHOR]

ABSTRACT Ultra-high molecular weight polyethylene (UHMWPE) has gained considerable fame due to its excellent wear and mechanical properties, though the inferior processability has restricted its further extensive applications. In this study, a combination of UHMWPE and poly(ethylene glycol) (PEG) was considered based on the recent reports, and aiming to further exploit the potential of PEG that acts as processing aid, and also to obtain greater enhanced processability along with other properties, the effects of incorporating maleic anhydride grafted polyethylene (MAPE) was thoroughly investigated. Rheological tests revealed a further significant reduction in melt viscosity of UHMWPE/PEG blends after MAPE introduced, showing a potential of better processability, while the flexural strength and toughness of UHMWPE blends experienced a satisfying increase without any obvious compromises in other mechanical properties. A slight improvement of thermal stability in UHMWPE ternary blends along with an increase of vicat softening temperature were characterized by thermal tests, while the crystallinity of UHMWPE was diminished after the introduction of MAPE. Morphology analysis indicated that better dispersion and decreased size of PEG particles were achieved in UHMWPE matrix when MAPE was incorporated, which confirmed the improved interfacial interactions and other reinforcements obtained in UHMWPE/PEG/MAPE blends. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42701. [ABSTRACT FROM AUTHOR]

Abstract: The low dispersibility of graphene in water, given its hydrophobic nature, is considered a serious problem that limits its use. Here, we describe a method to stably disperse graphene using a dispersant containing a tertiary amine and a pyrene group. The dispersant modifies the graphene surface via π–π stacking, allowing it to be dispersed in water. The dispersant undergoes a hydrophobic–hydrophilic transition upon being stimulated by CO2 and N2, exhibiting a faster response (reaction time of 1.5 min) and lower recovery temperature (40 °C) than those of compounds with amidine‐like structures. We found that the graphene modified by this gas‐sensitive dispersant exhibited reversible dispersion/aggregation behavior upon the bubbling/removal of CO2. The proposed method is a simple one for the reversible dispersion/aggregation of graphene by stimulating it with a gas and should be suitable for fabricating sensors, drug‐delivery systems, “smart” surfaces, and switching devices. [ABSTRACT FROM AUTHOR]

ABSTRACT Poly(glycerol sebacate) (PGS) is one of the new elastomers used for soft tissue engineering, while improving its limited mechanical strength is the biggest challenge. In this work, a novel biodegradable elastomer composite PGS/cellulose nanocrystals (CNCs) was prepared by solution-casting method and the mechanical properties, sol-gel contents, crosslink density, and hydrophilic performance were characterized. The thermal and degradation properties of composites were also investigated. Results show that the addition of CNCs into PGS resulted a significant improvement in tensile strength and modulus, as well as the crosslink density and the hydrophilicity of PGS. When the CNCs loading reached 4 wt %, the tensile strength and modulus of the composite reached 1.5 MPa and 1.9 MPa, respectively, resulting 204% and 158% increase compared to the pure PGS. Prolonging the curing time also improved the strength of both the neat PGS and PGS/CNCs composites according to the association and shift of hydroxy peaks around 3480 cm−1. DSC results indicate that the addition of CNCs improved both the crystallization capacity and moving capability of PGS molecular chain. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42196. [ABSTRACT FROM AUTHOR]

ABSTRACTS Background Standard triple therapy for Helicobacter pylori infection fails in up to one quarter of patients. Levofloxacin-based triple therapy may be more efficacious. Objective The aim of this paper was to compare levofloxacin and proton pump inhibitor-based triple therapy with standard triple therapy for H. pylori infection. Methods PubMed, Embase, Cochrane Central Register of Controlled Trials, , Google Scholar, and Ovid were systematically searched to identify randomized controlled trials comparing levofloxacin and proton pump inhibitor-based therapy with standard triple therapy in treatment-naive patients with H. pylori infection until August 2013. Results Ten randomized controlled trials involving 2676 patients (1357 in the levofloxacin group and 1319 in the control group) met the inclusion criteria. The pooled odds ratio by intention-to-treat analysis and by per protocol analysis in the levofloxacin regimen versus standard regimen was 1.28 [95% confidence interval (CI): 0.88-1.85] and 1.23 (95% CI: 0.82-1.84) by the random effects model, respectively. There was no statistical significance of the incidence of total side effects between the groups, but levofloxacin-based therapy was associated with a significant reduction in the incidence of taste disturbance compared with standard third therapy. Conclusion Levofloxacin-based therapy was as safe and effective as triple therapy for H. pylori infection and could be considered as an additional treatment option. However, more rigorous research is required to accurately assess the role of levofloxacin in eradicating H. pylori infection. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A new type of light-switchable 'smart' single-walled carbon nanotube (SWNTs) is developed by the reversible host-guest interaction between azobenzene-terminal PEO (AzoPEO) and pyrene-labeled host attached on the sidewalls of nanotubes via π-π stacking. The SWNTs hybrids not only are well dispersed in pure water, but also exhibit switchable dispersion/aggregation states upon the alternate irradiation of UV and visible light. Moreover, the SWNTs hybrids dispersion is preliminarily used as coating fluid to form transparent conductive films. The dispersant AzoPEO is removed by the contamination-free UV treatment, decreasing the resistance of the films. This kind of light-switchable SWNTs hybrids, possessing a ''green'' trigger and intact structure of the nanotube, may find potential applications in sensor of biomedicines, device fabrication, etc. Additionally, such a reversible host-guest interaction system may open up the possibility to control the dispersion state of SWNTs by other common polymers. [ABSTRACT FROM AUTHOR]

White-fungus-like NiS x microspheres have been synthesized on a large scale by using a simple hydrothermal method. The influence of the reaction time and the surfactant on the final products was investigated, and the formation mechanism was discussed. The synthesized white-fungus-like NiS x microspheres were used firstly as fillers in the fabrication of NiS x/polyvinylidene fluoride (PVDF) composites. Relationships between the loadings of the NiS x and wave-absorption properties of the composites were analyzed. The loss mechanisms of NiS x/PVDF with different loadings were also discussed according to their dielectric and magnetic behaviors. [ABSTRACT FROM AUTHOR]

A facile and environmentally friendly hydrothermal approach has been employed to synthesize size-controllable quasi-cubic α-Fe2O3 nanocrystals by using an aqueous solution of FeCl3 without any alkaline materials and stabilizing agent. The as-prepared products were carefully characterized and the growth mechanism is also discussed. This hydrothermal synthesis of such quasi-cubic structures implies a simple and low-cost route to prepare monodisperse nanomaterials on a large scale. The size-controllable synthesis of α-Fe2O3 is the first achieved successfully from 80 nm to 2 μm with constant structures. The synthesized α-Fe2O3 materials have different optical properties and stabilities in water, which are caused by the change of their band-gap energy and specific surface areas. Finally, the dielectric properties of synthesized α-Fe2O3 cubes were also investigated, and the differences caused by the particle sizes are discussed. [ABSTRACT FROM AUTHOR]

A series of CuS nanostructures were synthesized by a simple wet chemical method on a large scale in the presence of cetyltrimethylammonium bromide at low temperature. Three typical samples were selected to study the relationship between the morphologies and resulting physical properties. The optical properties of CuS hierarchical structures were investigated by UV/Vis and Raman spectroscopy and the excellent photocatalytic performance was also evaluated by measuring the decomposition rate of methylene blue under natural light. As an absorber, the selected CuS nanostructures possess excellent microwave absorbing properties. When the thickness of the absorber is 3.5 mm, the minimum reflection loss can reach −76.4 dB at 12.64 GHz. The enhanced photocatalytic performance and microwave absorbing properties were also explained based on morphologies of the nanostructures. [ABSTRACT FROM AUTHOR]

Acute pancreatitis (AP) is one of the most severe mortal inflammatory diseases worldwide, which is characterized by the over‐activation of reactive oxygen species (ROS)‐induced inflammation and pancreatic enzymes (PEs). As the PEs induced by ROS exacerbate the progression of AP, therefore, scavenging ROS within PEs is a prerequisite for AP treatment. To address the daunting issue, the engineered bio‐heterojunctions (bio‐HJs) consisting of Mo2C‐Au (MA), phospholipid, and protease inhibitors are devised. First, the decorated phospholipid and protease inhibitors facilitate the delivery of MA to the inflammatory pancreas as well as neutralization of PEs. Next, the MA exhibits outstanding antioxidant and ROS scavenging abilities, primarily benefiting from the increased empty orbitals on Mo attributed to electron transfer between the Mo2C and Au confirmed by theoretical calculation. The in vitro experiments demonstrate that the bio‐HJs exhibit splendid biocompatibility, excellent trypsin neutralization, and efficient ROS elimination properties. More encouragingly, the in vivo studies further reveal that the bio‐HJs prevent the infiltration of inflammatory cells and alleviate the severity of AP by suppressing the ROS‐induced activation of the TLR4‐ERK1/2 MAPK‐MLCK inflammatory signaling pathway. As envisioned, the engineered bio‐HJs represent a promising approach to the treatment and prevention of AP. [ABSTRACT FROM AUTHOR]

The evolution of eutectic carbide and granular pearlite, including secondary carbide and matrix ferrite, in 1.12C–8.1Cr–2.3Mo–1.08Si–0.32V alloy steel under spheroidization annealing is investigated. This procedure can be divided into two stages: austenitization in the range of 780–900 °C for 0.5–5 h and second annealing in the range of 740–780 °C for 3–7 h. The area fraction, size, number per unit area, and sphericity of carbides are analyzed under different annealing processes. The result indicates that the mean diameter of secondary carbides increases and the number of carbides per area decreases with the increase in temperature in two ranges of 780–900 and 740–780 °C. At >860 °C, the secondary carbide sufficiently spheroidizes, the eutectic carbide dissolves at the tip with a larger radius of curvature, and ferrite grains of the matrix are basically equiaxed. It can be found that the austenitizing stage plays a crucial role in nucleation and coarsening of secondary carbides, dissolution and segmentation of eutectic carbides, and recrystallization of matrix ferrite grains. The microhardness of the sample presents a decreasing tendency from fast to slow with the increase of the average diameter of secondary carbides. [ABSTRACT FROM AUTHOR]

The article focuses on findings of a study on petrogenesis of the early cretaceous laojunshan monzogranite at the southern margin of the North China Craton. It states that widely distributed intrusions are mainly of intermediate-acidic in composition and formed during the Late Jurassic-Early Cretaceous, and mentions that Laojunshan pluton, intruded in the amphibolites of the Kuanping Group consists of medium phenocryst monzogranites.

Iron single atom catalysts (Fe SACs) are the best‐known nonprecious metal (NPM) catalysts for the oxygen reduction reaction (ORR) of polymer electrolyte membrane fuel cells (PEMFCs), but their practical application has been constrained by the low Fe SACs loading (<2 wt%). Here, a one‐pot pyrolysis method is reported for the synthesis of iron single atoms on graphene (FeSA‐G) with a high Fe SAC loading of ≈7.7 ± 1.3 wt%. The as‐synthesized FeSA‐G shows an onset potential of 0.950 V and a half‐wave potential of 0.804 V in acid electrolyte for the ORR, similar to that of Pt/C catalysts but with a much higher stability and higher phosphate anion tolerance. High temperature SiO2 nanoparticle‐doped phosphoric acid/polybenzimidazole (PA/PBI/SiO2) composite membrane cells utilizing a FeSA‐G cathode with Fe SAC loading of 0.3 mg cm−2 delivers a peak power density of 325 mW cm−2 at 230 °C, better than 313 mW cm−2 obtained on the cell with a Pt/C cathode at a Pt loading of 1 mg cm−2. The cell with FeSA‐G cathode exhibits superior stability at 230 °C, as compared to that with Pt/C cathode. Our results provide a new approach to developing practical NPM catalysts to replace Pt‐based catalysts for fuel cells. [ABSTRACT FROM AUTHOR]

A simple way to develop single‐walled carbon nanotube (SWNT) hybrids with ‘smart’ light‐switchable properties is demonstrated by Y. Feng and co‐workers. On page 5010, they decorate SWNT surfaces with pyrene‐containing cyclodextrins via π–π stacking. After adding azobenzene‐modified poly(ethylene oxide), the SWNT hybrids are not only well dispersed in pure water through host‐guest interactions, but also exhibit switchable dispersion/aggregation states upon alternating irradiation of UV and visible light. [ABSTRACT FROM AUTHOR]