Efficient Electron Transfer from Electron-Sponge Polyoxometalate to Single-Metal Site Metal-Organic Frameworks for Highly Selective Electroreduction of Carbon Dioxide.

In this work, by combining the superiority of polyoxometalates (POMs) and catalytic single-metal site Co of metalloporphyrin, a series of mixed-valence POM-based metal-organic frameworks (MOFs) composites is synthesized by a post-modification method. The electron-transfer property of POM@PCN-222(Co) composite is significantly enhanced owing to the directional electron-transfer from POM to single-metal site Co in PCN-222(Co). In particular, H-POM@PCN-222(Co) gives a high Faradaic efficiency of 96.2% for electroreduction of CO2 into CO and good stability over 10 h. DFT calculations confirm that the directional electron transfer, which accelerates the multi-electron transfer from the electrode to active single-metal site Co, enriches the electron density of the Co center, and ultimately reduces the energy of the rate-determining step, thus increasing the catalytic activity of CO2 reduction reaction (CO2 RR). This work therefore suggests some new insight for the design of efficient electrocatalysts for CO2 RR.

[Apparent Diffusion Coefficient Histogram Analysis:Differentiation of Genetic Subtypes of Diffuse Lower-grade Gliomas].

Objective To explore the utility of apparent diffusion coefficient(ADC)histogram analysis for differentiating genetic subtypes of diffuse lower-grade gliomas. Methods A total of 55 patients with WHO grade Ⅱ/Ⅲ diffuse lower-grade gliomas who underwent preoperative routine brain magnetic resonance imaging and diffusion weighted imaging in our center were retrospectively evaluated.Among whom there were 14 patients with isocitrate dehydrogenase(IDH)wild-type gliomas(IDH wt group),19 patients with IDH-mutant 1p19q intact gliomas(IDH mut1p19q int group),and 22 patients with IDH-mutant 1p19q co-deleted gliomas(IDH mut1p19q del group).The whole-lesion ADC values derived from histogram analysis(including ADCmean,ADCminimum,ADC5%,ADC10%,ADC25%,ADC50%,ADC75%,ADC90%,ADC95%,ADCmaximum,mode,range,skewness,kurtosis,standard deviation,inhomogeneity,and entrophy)were measured for each patient.All parameters between the different genetic subtypes were compared by using the Student's t test or Mann-Whitney U test.Receiver operating curve(ROC)analysis was used to assess the diagnostic performance of ADC histogram in distinguishing the different genetic subtypes. Results Compared with IDH wt group,the ADC75%(P=0.021),ADC90%(P=0.015),ADC95%(P=0.014),ADCmaximum (P=0.035),range(P=0.009),standard deviation(P=0.001)and inhomogeneity(P=0.001)were significantly lower in IDH mut group;in contrast,the ADCminimum (P=0.031)and kurtosis(P=0.020)of IDH mut group were significantly higher than those in IDH wt group.The ADCmean(P=0.010),ADC5%(P=0.016),ADC10%(P=0.012),ADC25%(P=0.007),ADC50%(P=0.005),ADC75%(P=0.015),and mode(P=0.002)were significantly higher in IDH mut1p19q int group than in IDH mut1p19q del group.Inhomogeneity achieved the highest area under ROC(AUC)(0.811)in differentiating IDH mut gliomas and IDH wt gliomas,with a cutoff value of 0.229;the sensitivity and specificity were 85.7% and 73.2%.The mode achieved the highest AUC(0.744)in differentiating IDH mut1p19q int gliomas and IDH mut1p19q del gliomas,with a cutoff value was 1448.75×10 -6 mm 2/s;the sensitivity and specificity were 57.9% and 90.9%.Conclusion ADC histograms analysis may be helpful to differentiate genetic subtypes in lower-grade gliomas.

CircRNAFisher: a systematic computational approach for de novo circular RNA identification.

Circular RNAs (circRNAs) are emerging species of mRNA splicing products with largely unknown functions. Although several computational pipelines for circRNA identification have been developed, these methods strictly rely on uniquely mapped reads overlapping back-splice junctions (BSJs) and lack approaches to model the statistical significance of the identified circRNAs. Here, we reported a systematic computational approach to identify circRNAs by simultaneously utilizing BSJ overlapping reads and discordant BSJ spanning reads to identify circRNAs. Moreover, we developed a novel procedure to estimate the P-values of the identified circRNAs. A computational cross-validation and experimental validations demonstrated that our method performed favorably compared to existing circRNA detection tools. We created a standalone tool, CircRNAFisher, to implement the method, which might be valuable to computational and experimental scientists studying circRNAs.

Modelling noise annoyance responses to combined sound sources and views of sea, road traffic, and mountain greenery.

This paper studies the effect of human perception of visual and audio settings in an urban environment on annoyance. Video clips were projected onto a window panel of a living room to simulate neighborhood views containing different percentages of sea, mountain greenery, and road. These video clips were combined with audio stimuli corresponding to the congruent traffic and sea sounds. 246 participants were presented with 11 audio-visual stimuli and requested to respond to questions after the presentation. The collected responses were used to formulate a multivariate ordered logit model to predict the probability of evoking a high annoyance response. The findings revealed that views embracing mountain greenery close-by could enhance annoyance, which is contrary to other findings that greenery could always moderate noise annoyance. In addition, a 60% sea view was found to be able to yield 1 dB equivalent reduction in total sound pressure level. The trade-off was comparable to that achieved by having sea sound at a level 5 dB higher than road traffic noise. Exposure to road traffic noise level being 3 dB higher than sea sound level (i.e., signal-to-noise ratio = -3) together with a 60% sea view could provide an additional 1.5 dB equivalent reduction.

[Spectroscopy analysis of sulfonated poly (arylene ether ketone sulfone) on side chain for proton exchange membrane].

A series of poly (arylene ether ketone sulfone) s containing different amino content (Am-PAEKS) were prepared via direct polycondensation reactions, and then the sulfobutyl groups were grafted onto the Am-PAEKS by amidating reaction between the amide groups in Am-PAEKS and carboxylic acid groups in 4-(N-butane sulfonic) aminobenzoic acid. The structures of the compounds and the polymer were confirmed by FTIR and H-NMR. The new characteristic bands at 1 239 and 1 060 cm(-1) were assigned to O=S=O symmetric stretching vibration and asymmetric stretching vibration of the sulfonic groups in sulfonated poly (arylene ether ketone sulfone) on side chain (S-SPAEKS), and the structures of the polymers were further confirmed by 1H NMR spectra, and the proton peak at 1.64 ppm was assigned to the methyl in the middle of the pendant sulfonated aliphatic side chains, which show that the S-SPAEKS had been prepared successfully. In TGA curves we can observe two distinct weight loss steps, the first step was mainly attributed to the splitting-off of the sulfonic acid groups at 300 degrees C, and the second step was mainly attributed to the decomposition of the main chain of the S-SPAEKS at 450 degrees C. This series of SSPAEKS polymers exhibit excellent thermal properties by thermo gravimetric analysis, which can satisfy the basic requirements of proton exchange membrane (PEM) for fuel cells.

On-Site Cross-Linking of Polyacrylamide to Efficiently Bind the Silicon Anode of Lithium-Ion Batteries.

Silicon anode suffers from rapid capacity decay because of its irreversible volume changes during charging and discharging. As one of the important components of the electrode structure, the binder plays an irreplaceable role in buffering the volume changes of the silicon anode and ensuring close contact between various components of the electrode. Traditional PVDF binder is based on weak van der Waals forces and cannot effectively buffer the stress coming from silicon volume expansion, resulting in rapid decay of silicon anode capacity. In addition, most natural polysaccharide binders with a single force face the same problem due to poor toughness. Therefore, it is extremely important to develop a binder with good force and toughness between the silicon particles. Herein, polyacrylamide (PAM) polymer chains that are premixed homogeneously with various components are cross-linked on-site on the current collector via the condensation reaction with citric acid, forming a polar three-dimensional (3D) network with improved tensile properties and adhesion for both silicon particles and current collector. The silicon anode with the cross-linked PAM binder exhibits higher reversible capacity and enhanced long-term cycling stability; the capacity remains at 1280 mA h g-1 after 600 cycles at 2.1 A g-1 and 770.9 mA h g-1 after being subjected to 700 cycles at 4.2 A g-1. It also exhibits excellent cycle stability in silicon-carbon composite materials. This study provides a cost-effective binder engineering strategy, which significantly enhances the long-term cycle performance and stability of silicon anodes, paving the way for large-scale practical applications.

[Spectroscopy analysis application on proton exchange membrane with 1,3,4-oxadiazole].

A series of novel Sulfonted poly(arylene ether sulfone)s (SPAES) containing 1,3,4-oxadiazole are prepared via direct polycondensation reactions to precisely control the degree of sulfonation. The structures of these compounds were confirmed by FTIR, H-NMR and TGA. The characteristic peaks of transmittances spectra of C=N were found at 1 603 cm(-1) and by H-NMR further confirm the structures, which has been successful introducing the oxadiazole ring. In each TGA curve can observe two distinct weight loss steps, which the one at 300 degrees C and the second at 450 degrees C were mainly attributed to the splitting-off of sulfonic acid groups and decomposition of the main chain of the SPAES. The TGA exhibit excellent thermal properties may be satisfied with the basic requirements of proton exchange membrane (PEM) for fuel cells.

A Comparative Study of 2 Different Segmentation Methods of ADC Histogram for Differentiation Genetic Subtypes in Lower-Grade Diffuse Gliomas.

BACKGROUND: To evaluate the diagnostic performance of apparent diffusion coefficient (ADC) histogram parameters for differentiating the genetic subtypes in lower-grade diffuse gliomas and explore which segmentation method (ROI-1, the entire tumor ROI; ROI2, the tumor ROI excluding cystic and necrotic portions) performs better. MATERIALS AND METHODS: We retrospectively evaluated 56 lower-grade diffuse gliomas and divided them into three categories: IDH-wild group (IDHwt, 16cases); IDH mutant with the intact 1p or 19q group (IDHmut/1p19q+, 18cases); and IDH mutant with the 1p/19q codeleted group (IDHmut/1p19q-, 22cases). Histogram parameters of ADC maps calculated with the two different ROI methods: ADCmean, min, max, mode, P5, P10, P25, P75, P90, P95, kurtosis, skewness, entropy, StDev, and inhomogenity were compared between these categories using the independent t test or Mann-Whitney U test. For statistically significant results, a receiver operating characteristic (ROC) curves were constructed, and the optimal cutoff value was determined by maximizing Youden's index. Area under the curve (AUC) results were compared using the method of Delong et al. RESULTS: The inhomogenity from the two different ROI methods for distinguishing IDHwt gliomas from IDHmut gliomas both showed the biggest AUC (0.788, 0.930), the optimal cutoff value was 0.229 (sensitivity, 81.3%; specificity, 75.0%) for the ROI-1 and 0.186 (sensitivity, 93.8%; specificity, 82.5%) for the ROI-2, and the AUC of the inhomogenity from the ROI-2 was significantly larger than that from another segmentation, but no significant differences were identified between the AUCs of other same parameters from the two different ROI methods. For the differentiaiton of IDHmut/1p19q- tumors and IDHmut/1p19q+ tumors, with the ROI-1, the ADCmode showed the biggest AUC (AUC: 0.784; sensitivity, 61.1%; specificity, 90.9%), with the ROI-2, and the skewness performed best (AUC, 0.821; sensitivity, 81.8%; specificity, 77.8%), but no significant differences were identified between the AUCs of the same parameters from the two different ROI methods. CONCLUSION: ADC values analyzed by the histogram method could help to classify the genetic subtypes in lower-grade diffuse gliomas, no matter which ROI method was used. Extracting cystic and necrotic portions from the entire tumor lesions is preferable for evaluating the difference of the intratumoral heterogeneity and classifying IDH-wild tumors, but not significantly beneficial to predicting the 1p19q genotype in the lower-grade gliomas.