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In this study, diphenyl sulfoxide was prepared by oxidizing diphenyl sulfide with hydrogen peroxide using phosphotungstic acid as catalyst in semi-batch mode. In order to optimize the synthesis process, a four-factor three-level Box-Behnken design was adopted. The result showed that under the optimal condition, namely catalyst concentration 0.19 mmol/mol, oxygen-sulfur ratio 1.08, reaction temperature 30 ºC, and dosing time 15 min, the yield of diphenyl sulfoxide could reach up to 79.05%. In addition, the thermal behavior of synthesis process was systematically investigated using a reaction calorimeter (EasyMax 102) equipped with a situ FTIR monitoring. The receivable mechanism is that H 2 O 2 is activated by the catalyst and subsequently reacts with diphenyl sulfide to produce oxidized product. H 2 O 2 was relatively stable when PTA was used as catalyst. Thermal risk index was used to assess the thermal hazard of H 2 O 2 & PTA. Furthermore, risk matrix method as well as Stoessel criticality diagram was used to assess the thermal risk of the process and an unacceptable risk was obtained. One of the main hidden dangers was the potential chemical splatter caused by decomposition of H 2 O 2. It should be equipped with a pre-set quench or sufficient emergency discharge to avoid further loss. The results of this work proposed a solid foundation for the safe operation of this process and can be further used for scale-up. [ABSTRACT FROM AUTHOR]

Energy transfer mechanism between MoO 4 2− and Eu3+, Tb3+ ions in the (A) absence and (B) presence of the Fe3+ ions, and the process of the emission intensity were restored at the presence of F- ions. CaMoO 4 (CMO) doped with lanthanide ions (Eu, Tb) with hollow spindle-like morphology were prepared by a low temperature hydrothermal method, assisting with polymer, and its structural, morphology, surface binding information and photoluminescence properties were studied. Fluorescence quenching happened when the electron transferring of CMO phosphors was blocked. Based on this finding, these materials were employed as an inorganic sensor for Fe3+ ions assay. This facile preparation and assay may have potential applications in biomolecules diagnose and metal ions monitoring. [ABSTRACT FROM AUTHOR]

A systematic comparison between batch and continuous microfluidics systems was conducted for the synthesis of ZnWO 4 nanoparticles. A series of ZnWO 4 nanoparticles were prepared by different operating modes, initial concentration of reactants and residence time. The features of ZnWO 4 nanoparticles including microscopic morphology, particle size distribution and chemical structure were systematically characterized. The results showed that the continuous microfluidics system could obtain ZnWO 4 nanoparticles with a more uniform particle size compared with batch system. The size of ZnWO 4 are reduced from 92.6 to 65.2 nm by changing the reaction system. Besides, a low concentration of reactants is more suitable for preparing smaller particles ZnWO 4 nanoparticles. The average diameters of prepared ZnWO 4 nanoparticles was reduced to 50 nm in the condition that the residence time was 20 s and the concentration of reactants was 0.1 mol/L. Afterward, the degradation of dimethyl sulfoxide (DMSO) in the wastewaters was used as a probe reaction to evaluate the catalysis performance of prepared ZnWO 4 nanoparticles. This work indicates the potential opportunity of versatile continuous microfluidics technique for the fabrication of various multifunctional metal tungstates nanoparticles. [Display omitted] • ZnWO 4 nanoparticles were fabricated by batch and continuous microfluidics system. • Continuous microfluidics system is conducive to obtained small size nanoparticles. • The size of ZnWO 4 are reduced from 92.6 to 65.2 nm by changing the reaction system. • ZnWO 4 -6 nanoparticles had a BET of 90.1 m2/g and crystallite size of 10.39 nm. • The obtained ZnWO 4 were used as catalysis to remove the DMSO in wastewater. [ABSTRACT FROM AUTHOR]

We investigated the feasibility of using compressed sensitivity encoding (CS-SENSE) to accelerate high-resolution black-blood T1-weighted imaging with variable flip angles (T1WI-VFA) for efficient visualization and characterization of lenticulostriate arteries (LSAs) on a 3.0 T MR scanner. Twenty-five healthy volunteers and 18 patients with the cerebrovascular disease were prospectively enrolled. Healthy volunteers underwent T1WI-VFA sequences with different acceleration factors (AFs), including conventional sensitivity encoding (SENSE) AF = 3 and CS-SENSE AF = 3, 4, 5, and 6 (SENSE3, CS3, CS4, CS5, CS6, respectively) at 3 Tesla MRI scanner. Objective evaluation (contrast ratio and number, length, and branches of LSAs) and subjective evaluation (overall image quality and LSA visualization scores) were used to assess image quality and LSA visualization. Comparisons were performed among the 5 sequences to select the best AF. All patients underwent both T1WI-VFA with the optimal AF and digital subtraction angiography (DSA) examination, and the number of LSAs observed by T1WI-VFA was compared with that by DSA. Pair-wise comparisons among CS3, CS4, and SENSE3 revealed no significant differences in both objective measurements and subjective evaluation (all P > 0.05). In patients, there was no significant difference in LSA counts on the same side between T1WI-VFA with CS4 and DSA (3, 3–4 and 3, 3–3, P = 0.243). CS3 provided better LSA visualization but a longer scan duration compared to CS4. And, CS4 strikes a good balance between LSA visualization and acquisition time, which is recommended for routine clinical use. [ABSTRACT FROM AUTHOR]

To assess the value of amide proton transfer weighted (APTw) combined with intra-voxel incoherent motion (IVIM) imaging in differential diagnosis of stage I-II endometrial carcinoma (EC) and endometrial polyp (EP). A total of 53 female patients (37 cases with EC and 16 cases with EP) confirmed by surgical resection or biopsy from June 2019 to Jan. 2022 were retrospectively reviewed. All patients underwent 3.0 T magnetic resonance imaging (MRI) examination including diffusion weighted imaging (DWI), APTw and IVIM scans. The pure diffusion coefficient (D), pseudo-diffusion coefficient (D⁎), perfusion fraction (f), apparent diffusion coefficient (ADC) and APT values were independently measured by two observers. Intra-class correlation coefficients (ICC) were used to test the consistency of measurements by the two observers. Mann-Whitney U test was performed to analyze the difference of each parameter between EC and EP groups. Receiver operator characteristic (ROC) analysis was performed, and the Delong test was used for ROC curve comparison. Pearson's correlation analysis was used to assess the correlation between APTw and IVIM parameters. There was no significant difference in clinical manifestations between the two groups (P > 0.05). APT and D⁎ values of the EC group were significantly higher than those of the EP group [APT: 2.64 ± 0.50% vs. 2.05 ± 0.58%; and D⁎: (54.06 ± 36.06) × 10−3 mm2/s vs. (30.54 ± 16.67) × 10−3 mm2/s]. D, f and ADC values of EC group were significantly lower than those of EP group [D: 0.62(0.53,0.76) × 10−3 mm2/s vs. (1.45 ± 0.48) × 10−3 mm2/s; f: 22.18 ± 8.08% vs. 30.80 ± 8.92%; and ADC: (0.88 ± 0.16) × 10−3 mm2/s vs. (1.57 ± 0.43) × 10−3 mm2/s]. The area under ROC curves were observed as: AUC (IVIM+APT) > AUC (D) > AUC (ADC) > AUC (APT) > AUC (f) > AUC (D⁎). Delong test suggested statistical significance between AUC by APT and D, D and D⁎, D and f, D⁎ and ADC, APT and com(IVIM+APT), D⁎ and com(IVIM+APT), as well as f and com(IVIM+APT). No significant correlation between the APT and IVIM parameters was observed in either EC or EP group. Both APT and IVIM parameters showed statistical differences between EC and EP. With combination of APT and IVIM parameters, the diagnostic accuracy between EC and EP can be significantly improved. [ABSTRACT FROM AUTHOR]

Wetlands play a crucial role in the carbon cycle as they are the largest natural source of methane, a potent greenhouse gas. Changes in wetland hydrology can alter the rate of greenhouse gas release from wetlands and have the potential to alter Earth's carbon budget. However, the microbial dynamics underpinning these observations are poorly constrained. Here we combine monitoring of environmental parameters and greenhouse gas fluxes with monthly records of microbial phospholipid fatty acid (PLFAs) δ13C values to probe changes in microbial community and biogeochemistry in response to hydrological changes in a monsoon influenced subtropical wetland from central China. Our results show that water table depth is a key factor controlling the microbial community structure, with Gram-negative bacteria and actinobacteria increasing and fungi decreasing during dry and low water table periods. Meanwhile, the δ13C values of specific PLFAs decreased up to 12‰ during dry compared to wet periods. The extent of depletion varied, but PLFAs from Gram-negative bacteria were most depleted in 13C, indicative for a rapid increase in methanotrophy (methane consumption) during these dry periods. Furthermore, the methane emission of the wetland was drastically reduced and even had negative flux values during dry periods, suggesting that the increased methanotrophy led to a reduced methane flux and a temporary shift of the wetland from a methane source to a methane sink. Our results indicate that short-term hydrological variations lead to a rapid response in microbial community and carbon metabolic activity that directly influences wetland carbon dynamics and greenhouse gas emissions. [ABSTRACT FROM AUTHOR]

To explore the value of amide proton transfer-weighted (APTw) magnetic resonance imaging (MRI) for differential diagnosis of fibroadenomas and malignant breast tumors. This prospective study enrolled 56 patients with suspected breast tumors and performed APTw imaging. Based on the histopathology results, patients were divided into group 1 with malignant breast tumors (n = 41) and group 2 with fibroadenomas (n = 15). The measured image parameters (APTw value, ADC value, type of Time of Intensity Curve, maximum tumor diameter in image) and the maximal diameter of the tumors measured from surgical resection were compared between the two groups, and the diagnostic performance based on these parameters was quantified with ROC curve. Spearman's correlation coefficient was used to analyze the association between APTw or ADC values and ER, PR, HER2, and Ki-67 expressions. The intraclass correlation coefficients (ICC = 0.87 and 0.91) indicated a good inter-observer agreement of the measured APTw values. APTw values of malignant lesions were significantly higher than those of fibroadenomas (3.21 ± 1.04% vs 1.50 ± 0.54%, p < 0.001). Area under the curve (AUC) obtained from APTw imaging, DWI, DCE, APTw imaging+DWI, APTw imaging+DWI, and APTw imaging+DWI + DCE was 0.959, 0.897, 0.976, 0.997, and 1 respectively. The APTw value showed a negative correlation with ER expression (r = −0.357). APTw imaging yielded similar diagnosis performance in discriminating fibroadenomas and malignant breast tumors when compared to the DCE and better than DWI imaging, and provided supplement information on tumor cell activity to DWI images. The APTw value showed correlations with some prognostic factors for breast cancer. • APTw imaging can be used prospectively differentiating benign from malignant tumors. • APTw imaging yielded similar diagnosis performance in discriminating benign and malignant breast tumors when compared to the DCE and better than DWI imaging. • The APTw value showed a negative correlation with ER expression. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the differentiation efficiency of texture analysis of T1WI, T2WI and contrasted-enhanced T1WI MRI sequences in gliomas with and without IDH1 mutation based on entire tumor region.Materials and Methods: A total of 42 patients with histopathologically confirmed gliomas, including 21 patients carrying IDH1 mutation (IDH1mutation group) and 21 with wild-type IDH1 (IDH1wt group) were included in this study. The preoperative MRI and clinical data were collected. The regions of interest (ROIs) covering the entire tumor and edema were manually delineated on axial slices using O.K. (Omni Kinetics, GE Healthcare, China) software; and the histogram and GLCM features based on T1WI, T2WI and contrasted-enhanced T1WI sequences were automatically generated.Results: Based on contrasted-enhanced T1WI features, the inertia resulted as the best feature for diagnosis, with the AUC of 0.844. Furthermore, the AUC for gliomas prediction with IDH1mutation was 0.800 for cluster prominence. IDH1-mutation was differentiated on T2WI with the highest AUC of 0.848, which corresponded to GLCM Entropy. After modeling, the accuracy of the contrasted-enhanced T1WI, T1WI, and T2WI features model was 0.952, 0.857, and 0.738, respectively. The AUC of Joint VariableT1WI+C for predicting IDH1mutation was 0.984, while the AUC of Joint VariableT1WI for predicting the same mutation was 0.927. The diagnostic efficiency of Joint VariableT2WI was also desirable.Conclusion: MRI texture analysis could be used as a new noninvasive method for identification of gliomas with IDH1 mutation. The present results show that the Joint Variable derived from conventional MR imaging histogram and GLCM features is suitable for precise detection of IDH1-mutated gliomas. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the application of conventional MRI histogram analysis based on the whole tumor measurement on assessing meningioma grading.Materials and Methods: This retrospective study was approved by the institutional review board. A total amount of 90 patients with meningioma were enrolled and the preoperative MRI of them were analyzed. To be specific, the patient group were consisted of 45 patients with grade I, 38 with grade II, and 7 with grade III meningioma. Grade I meningioma is classified as low grade meningioma (LGM), whereas Grade II and III meningioma were combined and classified as high grade meningioma (HGM). ROIs were drawn along the edge of the tumor on each section of T1WI, T2WI, and contrasted T1WI. 3D ROI signal intensity histogram and all its parameters were obtained. Independent t-test and Kruskal-Wallis test were used for comparison between two groups. Univariate logistic regression analysis and Spearman's correlation analysis were used to screen for the parameters with high predictive efficiency, while multivariate logistic regression analysis was used to determine the optimal model for the classification of meningioma.Results: There were significant differences observed between HGM and LGM groups regarding to histogram volume count, uniformity of three sequences, range of T1WI and T2WI, kurtosis, standard deviation, variance, max intensity of T2WI, skewness, mean deviation, minimum intensity, mean value, the 5th percentile, the 10th percentile, the 25th percentile, the 50th percentile, the 75th percentile, and the 90th percentile of contrasted T1WI. Volume count and uniformity were high predictive parameters in distinguishing HGM from LGM. Logistic regression model included contrasted T1WI histogram parameters (i.e. minimum intensity, volume count, skewness, uniformity, and the 75th percentile) showed the best diagnostic efficiency for meningioma grade, with a sensitivity and specificity of 83.9% and 77.4% (AUC = 0.834, cutoff value = 0.413), respectively. The optimal model was achieved with a sensitivity of 71.4% and a specificity of 78.6% in the test set (AUC = 0.791, cutoff value = 0.413).Conclusions: Histogram analysis of conventional MRI based on 3D tumor measurement can be applied in the assessment of meningioma grading in clinical. [ABSTRACT FROM AUTHOR]

Upconversion nanoparticles (UCNPs) are promising for bioimaging, sensing, and other applications, but their upconversion (UC) efficiency is far from satisfactory. Organic dye sensitization is considered to be an effective strategy to improve the performance of UCNPs. In this work, we provide direct evidence that organic sensitizer surpasses inorganic sensitizer in sensitization capability. To maximize the performance of dye-sensitized UCNPs, three critical factors, namely different optically inert lanthanide ions, Yb3+ doping concentration, and particle size, are systemically investigated and optimized. It is found that the optimal Yb3+ doping concentration and particle size are determined to be 20% and ~19 nm for dye-sensitized UCNPs, while different optically inert lanthanide ions have negligible influence on this system. Importantly, our results suggest that dye sensitization is more favorable for improving the performance of smaller-sized UCNPs. Although ultrasmall UCNPs (<10 nm) are desirable for biomedical applications UCNPs due to their reduced toxicity, they suffer from extremely low UC efficiency and weak brightness. Fortunately, the strategy of dye sensitization turns out to be particularly useful for producing ultrasmall and ultrabright UCNPs, which are desirable for biomedical applications. [Display omitted] • Organic sensitizer is superior over inorganic sensitizer in sensitization capability. • The optimal Yb3+ doping concentration and particle size are determined to be 20% and ~19 nm for dye-sensitized upconversion nanoparticles, while the doping of different optically inert lanthanide ions has negligible influence on this system. • The strategy of dye sensitization is particularly useful for producing ultrasmall and ultrabright upconversion nanoparticles. [ABSTRACT FROM AUTHOR]

• Actual fatigue damage and operation data were comprehensively measured. • Multiple operation factors were investigated. • Rail corrugation and 8th order wheel polygon were determined. • The major fatigue damage was caused by rail corrugation combined with wheel polygon. Metro vehicle bogie frame is usually subjected to complex external excitations. The fatigue damage accumulation of bogie frame is induced by multiple elements and may even lead to failure hazard. Therefore, a comprehensive investigation into the influencing elements was conducted in this paper. To achieve this purpose, a targeted field test was first carried out under normal operating conditions to obtain the dynamic stress and operating state data. Then, P2 resonance frequency of vehicle-track system was calculated, and rail corrugation and 8th order wheel polygon were determined. Damage analysis was performed for rail corrugation, wheel polygon, rail joint, velocity, and passenger capacity. The results indicate that rail corrugation accompanied with wheel polygon are the main reasons for the damage of bogie frame. This research will be beneficial for ensuring operation safety and developing reasonable maintenance schedule for metro vehicle. [ABSTRACT FROM AUTHOR]

• A review of OGFC was conducted by emphasizing the drainability and functionality. • Cost-benefit analysis about OGFC was presented. • Challenges and prospects of OGFC were described. During the last few years, the use of Open-Graded Friction Course (OGFC) as a wearing surface material has gained a great concern due to the various benefits in terms of safety, economy, and environment. This paper reviewed the state-of-the-art research of OGFC, and the emphasis was laid on durability and functionality. By addressing the issues of durability, a mapping from materials to durability was established, which was beneficial in prolonging the lifespan. By discussing the issues of durability and noise-reduction, the internal mechanisms of OGFCs' functionality can be identified, so that the functional effectiveness of OGFCs could be better maintained. Cost-benefit analysis of the application of OGFC was also summarized. Besides, the current and future challenges were identified to enhance the performance of OGFC to facilitate the widespread use. Due to the extensive benefits of OGFC pavements, there exists an expansive scope for further research to promote the understanding of the material better, which will make it a promising sustainable pavement material in future. [ABSTRACT FROM AUTHOR]

Concretes with binary and ternary blends of Portland cement, granulated-blast furnace slag (GGBS), and carbon fiber (CF) were prepared to investigate their effects on mechanical performance, drying shrinkage and creep behaviors. Nine types of concrete mixtures were prepared and tests were conducted during a long testing period which was up to 180 days. Research showed that GGBS and CF played a detriment effect on short-term compressive strength. GGBS could improve the workability of concretes, while CF presented an opposite effect. Concrete with the addition of CF showed superior drying shrinkage resistance and creep resistance, while GGBS increased the drying shrinkage and creep potentials. The coupling effect of GGBS and CF on the drying shrinkage and creep performance highly depended on the relative content of GGBS and CF. Analysis of variance (ANOVA) was performed to analyze the importance of GGBS and CF on the drying shrinkage and creep performance. Results showed that test period, content of GGBS, and content of CF were all significant factors in influencing the drying shrinkage and creep behaviors. Models to predict the drying shrinkage strain and creep coefficient were proposed by considering different proportions of cement, GGBS, and CF, and the models give promising results. Besides, the cost-benefit analysis and the environmental impact were also quantitively studied, and results showed that concretes incorporated with 20% GGBS in mass and 0.1% or 0.2% CF in volume presented both good cost-benefit effectiveness and low environmental impact. • Concrete incorporated with GGBS and carbon fiber CF was prepared. • The mechanical, drying shrinkage and creep behaviors were investigated. • Analysis of variance (ANOVA) was conducted. • Models were established to predict the shrinkage strain and creep coefficient. • Cost-benefit and environmental impact analysis were performed. [ABSTRACT FROM AUTHOR]

Eu3+ activated CaWO 4 (CWO) phosphors were prepared via a modified hydrothermal process. In present work, the phosphors illustrated enhanced emission properties by the assistance of poly acrylic acid (PAA). The phase structure, micromorphology, photoluminescence properties and luminescence enhancement mechanism of the as-prepared samples were investigated. The as-prepared PAA assisted samples exhibited significantly enhanced red emission peaking at 595 nm and emission intensity increased by about 8 times. The results indicated that CWO: Eu3+ samples could be a potential candidate of red phosphor for white light-emitting diodes (WLEDs). The enhanced red-emission spectra of CaWO 4 assisted by PAA. (Insets are the corresponding luminescence photograph and CIE diagram of CaWO 4 with different condition of PAA). Image 1009 • A low temperature hydrothermal method assisting with PAA for preparation of CaWO 4 activated with Eu3+ ions is proposed. • The red-emission intensity of CaWO 4 :Eu3+ increases about 8-fold after modificating by PAA. • The enhancement mechanism of CaWO 4 :Eu3+ is discussed in detail. [ABSTRACT FROM AUTHOR]