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We theoretically demonstrate a scheme for efficiently generating near-circularly polarized isolated attosecond pulses from mixed gases driven by non-integer frequency ratio two-color multicycle laser fields. It is shown that isolated attosecond pulses with a duration of 310 as can be generated, exhibiting non-zero ellipticity with values reaching as high as 0.9. Further analysis reveals that the ellipticities of these isolated attosecond pulses are attributed to the interference of high-order harmonics generated from different components of the mixture. When the components in the mixture have opposite orbital parity, constructive and destructive interference will occur for left- and right-circularly polarized harmonic components, or vice versa. Additionally, the temporal profile of the isolated attosecond pulse depends solely on the driving fields, while the polarization is determined by the gas mixture. The obtained elliptically polarized isolated attosecond pulses may serve as a promising tool for manipulating ultrafast dynamics in magnetic materials and chiral media. • Highly elliptically polarized attosecond pulses are generated from mixed gases. • We apply the non-integer frequency ratio two-color fields for generating the IAPs. • An IAP with ellipticity up to 0.9 is produced, and its duration is 310 as. [ABSTRACT FROM AUTHOR]

PDA-functionalized h-BN nanomaterials (Ph-BN) were used to reinforce the electrodeposited Ni W coatings. Compared with the h-BN nanomaterial, Ph-BN has better dispersion in the plating solution, which can effectively improve the mechanical and corrosion resistance of the coating. Compared with the Ni W coating, the microhardness value of the Ni-W/Ph-BN coating (662.8 Hv) was increased by 33.47 % and the friction coefficient (0.382) was reduced by 41.86 %. This is due to the special ceramic composite layered structure of Ph-BN namely the combination of flexible unit PDA structure and rigid unit h-BN structure, which will synergistically hinder the shedding of the coating during the friction process and help to improve the wear resistance of the coating. The R ct value of Ni-W/Ph-BN is 34,500 Ω•cm2, which is 105.36 % higher compared to Ni W coating. Ni-W/Ph-BN also has the smallest corrosion rate (0.0465 mm•a−1), which is 45.74 % lower relative to Ni W coating. The uniformly dispersed Ph-BN nanosheets in the coating prolong the corrosion path for corrosive ions. Besides, the PDA has the effect of anchoring Fe2+/ Fe3+, which will be beneficial for the composite coating corrosion resistance improvement. [Display omitted] • The first application of PDA-functionalized h-BN (Ph-BN) to Ni W coatings • Ph-BN affects the structure and properties of Ni W coatings. • The special laminated composite structure of Ph-BN provides excellent wear reduction. • Ph-BN improves the structural defects of the coating and hinders the corrosion reaction. [ABSTRACT FROM AUTHOR]

Ca2ZrSi4O12:R (CZSO:R) (R = Eu3+, Bi3+, and Eu3+/Bi3+) phosphors are successfully synthesized in air through high-temperature solid-state method. Host CZSO and CZSO:Bi3+ phosphor with excitation at 300 nm emit blue light. CZSO:Eu3+ phosphor with changing Eu3+ content shows tunable emission from white to red light under excitation at 300 nm and only emits red light under excitation at 395 nm. CZSO:10%Eu3+, Bi3+ phosphor shows tunable emission from blue to red light under excitation at 300 nm, and only emits red light with excitation at 395 nm when Bi3+ ion concentration is changed. Luminescence properties of CZSO:Eu3+ phosphor may be improved by co-doping Bi3+ ion. The luminous mechanism of CZSO:Eu3+, Bi3+ phosphor is explained by the energy level diagrams of Bi3+ and Eu3+ ions. [ABSTRACT FROM AUTHOR]

A series of CaZrO3:Bi3+, CaZrO3:Eu3+, CaZrO3:Eu3+, Bi3+, and CaZrO3:Eu3+, Bi3+, Li+ phosphors are synthesized by high-temperature solid-state reaction method in air. Their luminescence properties are researched, compared, and analyzed. CaZrO3:Bi3+ phosphor under excitation at 310 nm emits deep-blue light with chromaticity coordinate (0.1612, 0.0254). CaZrO3:Eu3+ phosphor under excitation at 310 and 395 nm shows red-emitting with chromaticity coordinate (0.6386, 0.3611). CaZrO3:Eu3+, Bi3+ phosphor under excitation at 310 nm exhibits a systematically varied hue from deep-blue to red light by changing Eu3+ ion concentration, and that with excitation at 395 nm only emits red light with chromaticity coordinate (0.6386, 0.3611). The energy transfer process from Bi3+ to Eu3+ ions may be indicated by their spectral properties. The optimal Eu3+ and Bi3+ ions concentrations are 5 mol% and 0.9 mol%, respectively. The emission intensity CaZrO3:Eu3+, Bi3+ phosphor may be enhanced about 1.6 times due to the co-doping Li+ ion as charge compensator role. The luminous mechanism of CaZrO3:Eu3+, Bi3+ phosphor is explained by the simplified energy level diagrams of Bi3+ and Eu3+ ions. [ABSTRACT FROM AUTHOR]

• A composite fuel with zirconium (Zr) -coated TRISO particles embedded in metal zirconium matrix was designed. • The Zr coating can effectively prevent TRISO fuel particles from contact and cracking during sintering. • The decomposition-adhesion-sintering-grain growth deposition mechanism of Zr coating via FB-CVD was proposed. With the development of advanced reactors, it is critical to improve the safety of nuclear reactors. Safety primarily depends on the ability to block fission products and the ability to discharge decay heat of fuel elements. To enhance the ability to retain the release of fission products and achieve high thermal conductivity, a novel fuel pellet was developed, consisting of zirconium (Zr)-coated TRISO particles embedded in a zirconium metal matrix. The zirconium coating was deposited via fluidized-bed chemical vapor deposition (FB-CVD), and the deposition mechanism of Zr coating via FB-CVD was proposed. The consolidation process of Zr-coated TRISO particles in the Zr matrix was achieved via spark plasma sintering (SPS). The microstructure and mechanical properties of Zr coating and the pellet were investigated via SEM and nanoindenter. The results proved the effectiveness of zirconium coating in preventing TRISO fuel particles from contact and cracking during sintering. [ABSTRACT FROM AUTHOR]

A series of MgTiO3:Mn4+, MgTiO3:Mn4+, Ge4+, and MgTiO3:Mn4+, B3+ phosphors are prepared by the high temperature solid-state reaction method in air. X-ray powder diffraction (XRD) patterns confirm that there is only pure phase in all samples. The samples are composed of microparticles with irregular shapes. Their excitation spectra monitored at 658 nm may be observed in the range of 200-600 nm and their emission spectra with excitation at 330 nm cover the region from 600 to 800 nm due to the 2E → 4A2 transition of Mn4+ ion. The chromaticity coordinate is (0.7233, 0.2767). The optimal Mn4+ content is ~ 0.3% in MgTiO3:Mn4+ phosphor. The luminescence intensity and quantum efficiency of MgTiO3:Mn4+ phosphor may be obviously improved by adding Ge4+ ion and H3BO3. The experimental results are helpful for the luminescence property improvement of other Mn4+ doped materials. [ABSTRACT FROM AUTHOR]

Fungal infections and antifungal resistance are the increasing global public health concerns. Mechanisms of fungal resistance include alterations in drug-target interactions, detoxification by high expression of drug efflux transporters, and permeability barriers associated with biofilms. However, the systematic panorama and dynamic changes of the relevant biological processes of fungal drug resistance acquisition remain limited. In this study, we developed a yeast model of resistance to prolonged fluconazole treatment and utilized the isobaric labels TMT (tandem mass tag)-based quantitative proteomics to analyze the proteome composition and changes in native, short-time fluconazole stimulated and drug-resistant strains. The proteome exhibited significant dynamic range at the beginning of treatment but returned to normal condition upon acquisition drug resistance. The sterol pathway responded strongly under a short time of fluconazole treatment, with increased transcript levels of most enzymes facilitating greater protein expression. With the drug resistance acquisition, the sterol pathway returned to normal state, while the expression of efflux pump proteins increased obviously on the transcription level. Finally, multiple efflux pump proteins showed high expression in drug-resistant strain. Thus, families of sterol pathway and efflux pump proteins, which are closely associated with drug resistance mechanisms, may play different roles at different nodes in the process of drug resistance acquisition. Our findings uncover the relatively important role of efflux pump proteins in the acquisition of fluconazole resistance and highlight its potential as the vital antifungal targets. • Deep-coverage proteomics revealed the role of different pathways in the development process of fungal drug resistance. • The sterol pathway responds violently under short-time drug treatment and returns to normal after resistance acquisition. • Multi ABC transporters play leading role in sustaining fluconazole resistance mechanisms. [ABSTRACT FROM AUTHOR]

Bicalutamide (BIC) is one fluorine-containing drug with poor aqueous solubility, and it is essential to study the polymorphism of BIC, especially the metastable polymorphs and amorphous phase, to improve the oral effect. Selective crystallizations of BIC amorphous phases and solutions were studied and further explained and predicted by using mid-frequency Raman difference spectra (MFRDS) here. The relationships among various polymorphs and solutions of BIC were established by calculating the values of average deviation (a. d., the average value of absolute value of the intensity of MFRDS) and standard deviation (s. d.) of the MFRDS. And the possible routes to obtain metastable Form II and amorphous BIC were proposed based on the MFRDS results. Metastable Form II can be obtained by recrystallization of the amorphous BIC prepared through melt-quenching method. Amorphous BIC without additives can be prepared through a quicky evaporation process of acetone and ethyl acetate solutions, which was reported for the first time. The MFRDS results confirmed the presence of residual acetone and ethyl acetate in amorphous BIC obtained by evaporation, and the residual solvents changed the recrystallization products of amorphous BIC. MFRDS analysis can be a useful tool to guide the preparation and selective crystallization of metastable polymorphs and amorphous phase. [Display omitted] [ABSTRACT FROM AUTHOR]

Very-high-temperature gas-cooled reactors (VHTRs) with outlet temperatures above 1273 K show higher thermal efficiencies, which require fuel elements to operate at higher temperatures. In such situations, the conventional silicon carbide (SiC) coatings in TRISO particles might not be able to adapt to such high temperatures, and zirconium carbide (ZrC) can function as a potential fission product barrier material. For ZrC coating, controlling the stoichiometric ratio is a key challenge in the preparation process in fluidized bed. In this paper, a novel solid precursor feeding mode was proposed, combining quantitative powder feeding with cold transport. By controlling the powder feeding rate of ZrCl 4 and the flow rate of propylene, the C/Zr atomic ratio in ZrC coating was controlled accurately. ZrC coatings with different stoichiometric ratios were successfully prepared via fluidized-bed chemical vapor deposition (FB-CVD). The ZrC coatings were subjected to high temperature heat treatment for different times from 2473 to 2673 K under argon atmosphere and the microstructure and property evolutions after high-temperature heat treatment were investigated. The deposition mechanism of ZrC coating was proposed. [ABSTRACT FROM AUTHOR]

In this paper, Ni-W/La 2 O 3 composite coatings were successfully prepared by pulse electrodeposition technology. The effect of the nano-La 2 O 3 content in the plating solution on the structure and properties of the plated layers were evaluated. We find that nano-La 2 O 3 can improve the situation of structural defects such as microcracks in the coating and serve to increase the thickness of the coating. Meanwhile, the Ni-W/La 2 O 3 (4 g‧L−1) composite coating has the smallest crystallite size (6.52 nm). Compared with the Ni-W composite coating, the microhardness of Ni-W/La 2 O 3 (4 g‧L−1) composite coating increased by 38.61 % (the microhardness value is 682.30 Hv), while the friction coefficient decreased by 46.57 % (the average coefficient of friction is 0.246) and the corrosion rate decreased by 81.54 % (the corrosion rate is 0.0498 mm‧a−1). [Display omitted] • The hardness value of Ni-W/La 2 O 3 (4 g‧L−1) composite coating increased by 38.61 %. • The COF of Ni-W/La 2 O 3 (4 g‧L−1) composite coating decreased by 46.57 %. • The corrosion rate of Ni-W/La 2 O 3 (4 g‧L−1) composite coating decreased by 81.54 %. [ABSTRACT FROM AUTHOR]

• Spatial clustering analysis of anthropogenic sources of heavy metals in sediments of Taihu Lake. • The potential risk of sediment properties at the pollutant sink was assessed. • Identification of the comprehensive risk areas for sediments heavy metal pollution based on the source-sink theory. The combined effect of pollution source discharge and sediment adsorption leads to the rapid enrichment of heavy metals and other pollutants in lake sediments, which poses a serious threat to the lake ecosystem. Accurately identifying the risk areas of heavy metals in sediments is the key to lake sediment pollution control. Taking Taihu Lake as the study area, combined with the ecological risk status of heavy metals in sediments, the spatial clustering characteristics of pollution sources and the clustering information of sediment attributes, a potential toxic risk area identification method based on sediment source aggregation class (SLISA-SCA) was established. Through the source analysis of heavy metals in sediments, heavy metals such as Cr, Mn, Cu and Zn in Taihu Lake sediments were identified to have originated from natural sources and were subsequently disturbed by human activities to a certain extent. Cd was found to be strongly affected by human activities, and almost all Taihu Lake sediments were affected to varying degrees. In addition, the anthropogenic sources of heavy metals show high concentration clustering characteristics in the lake bay. By K-means cluster analysis of sediment attributes, three significant differences were obtained, which were determined as potential high pollution risk areas, potential medium risk areas and potential low risk areas, and the proportions were 5.6%, 27.6% and 66.8%, respectively. The SLISA-SCA model established in this study, from the perspective of source sinks, comprehensively considers the risks caused by pollution sources and sediment attributes to sediments and divides Taihu Lake into five different risk control areas (high-risk control area, potential high-risk control area, potential risk control area, potential low-risk control area and low-risk control area). This study identified areas with different levels of heavy metal pollution in Taihu Lake sediments, proposes corresponding treatment measures, and provides a scientific and systematic method and technology for the pollution management of other river and lake sediments in the world. [Display omitted] [ABSTRACT FROM AUTHOR]

With the development of deep learning, scene text detection methods have made great progress in recent years. Most text detection methods are based on bounding box prediction with a 0-1 discrete distribution; thus, separating adjacent text instances is difficult. Direct prediction of the bounding box also renders difficult the detection various shapes of text, such as quadrangular text and curved text. In this work, we design a 2D progressive kernel for describing the progressive variety of text regions. It transforms the original ground truth (GT) of bounding boxes into the GT of a 0-1 progressive probability distribution. We also propose a novel progressive region prediction network (PRPN) with directional pooling for predicting the probability distributions of text regions. Then, a postprocessing algorithm is used to transform the probability distributions of the text regions into bounding box output for text detection. Experiments on standard datasets, including ICDAR 2013, ICDAR 2015, MSRA-TD500, and SCUT-CTW1500, demonstrate that the proposed method outperforms state-of-the-art methods in terms of accuracy and robustness. The method obtains an F-measure of 86.0% on ICDAR 2015 and 81.4% on SCUT-CTW1500. The code is available at https://github.com/xinyu-ch/ProgressiveTextDetection. [ABSTRACT FROM AUTHOR]

• Magnetic ConA-nanoparticles were prepared to enrich the glycosylated proteins in human urine. • Quantitative proteomics identified differentially regulated glycosylated proteins in the urine of lung cancer patients. • Glycosylated cathepsin C and transferrin were significantly upregulated in the urine of SCLC patients. [Display omitted] Lung cancer has high morbidity and mortality and small cell lung cancer (SCLC) is a highly invasive malignant tumor with a very unfavorable survival rate. Early diagnosis and treatment can result in better prognosis for the SCLC patients but current diagnostic methods are either invasive or incapable for large-scale screen. Therefore, discovering biomarkers for early diagnosis of SCLC is of importance. In this work, we covalently coupled Concanavalin A (ConA) to functionalized magnetic nanoparticles to obtain magnetic ConA-nanoparticles (ConA-NPs) for the enrichment of glycosylated proteins. We then purified glycosylated proteins in 36 urine samples from 9 healthy controls, 9 SCLC patients, 9 lung adenocarcinoma (LUAD) patients, and 9 lung squamous cell carcinoma (LUSC) patients. The purified glycosylated proteins were digested and analyzed by LC-MS/MS for identification and quantification. Among the 398 identified proteins, 20, 15, and 1 glycosylated protein(s), respectively, were upregulated in the urine of SCLC, LUAD, and LUSC patients. Immunoblotting experiments further demonstrated that cathepsin C and transferrin were significantly upregulated in the ConA-NP purified urine of SCLC patients. This work suggests that glycosylated cathepsin C and transferrin might be able to serve as potential biomarkers for the noninvasive diagnosis of SCLC patients. [ABSTRACT FROM AUTHOR]

In a gymnasium in Harbin, China, a survey was performed under different lighting conditions to determine the factors influencing the user assessment of daylight environments and define visual comfort thresholds for mass sports activities. Nine subjects experienced the simulated visual environment of basketball shooting by observing the backboard from a designated position, and their visual comfort preferences were evaluated through subjective questionnaires and objective physiological measurements. A total of 108 diverse visual environments were recorded using high dynamic range photography to acquire luminance. The questionnaire factor analysis suggested that the user assessments were mainly determined by their emotional state, glare perception, and visual clarity. The physiological baseline state threshold was proposed based on the physiological measurement data; it described the daylight luminance of the subjects when their physiological value under only natural lighting reached their physiological value under electric lighting. The analysis of the luminance and questionnaire data defined user visual comfort thresholds under only natural lighting: an acceptable average luminance threshold of 42 cd/m2 and a comfortable average luminance threshold of 80 cd/m2 in the entire field of view (FOV); an acceptable maximum luminance threshold of 4800 cd/m2 and a comfortable maximum luminance threshold of 6700 cd/m2 in the entire FOV; a recommended average luminance threshold of 100 cd/m2 in the target area; an acceptable luminance ratio threshold of 42 and a comfort luminance ratio threshold of 21 between the average luminance in window area and the entire FOV. • Luminance parameter thresholds for visual comfort were defined by integrating questionnaires and physiological measurement. • Subjective questionnaire factors that influence user assessment were investigated in a daylit gymnasium. • Participants' heart rate variability and electrodermal activity were measured under various light settings. • Light environment parameters, questionnaire factors, and physiological indexes correlated with each other were extracted. • A new index was proposed to quantified emotional perception under daylight environments. [ABSTRACT FROM AUTHOR]