Stabilization of Ni-containing Keggin-type polyoxometalates with variable oxidation states as novel catalysts for electrochemical water oxidation †

The development of new recyclable and inexpensive electrochemically active species for water oxidation catalysis is the most crucial step for future utilization of renewables. Particularly, transition metal complexes containing internal multiple, cooperative metal centers to couple with redox catalysts in the inorganic Keggin-type polyoxometalate (POM) framework at high potential or under extreme pH conditions would be promising candidates. However, most reported Ni-containing POMs have been highly unstable towards hydrolytic decomposition, which precludes them from application as water oxidation catalysts (WOCs). Here, we have prepared new tri-Ni-containing POMs with variable oxidation states by charge tailored synthetic strategies for the first time and developed them as recyclable POMs for water oxidation catalysts. In addition, by implanting corresponding POM anions into the positively charged MIL-101(Cr) metal–organic framework (MOF), the entrapped Ni2+/Ni3+ species can show complete recyclability for water oxidation catalysis without encountering uncontrolled hydrolysis of the POM framework. As a result, a low onset potential of approximately 1.46 V vs. NHE for water oxidation with stable WOC performance is recorded. Based on this study, rational design and stabilization of other POM-electrocatalysts containing different multiple transition metal centres could be made possible

Prognostic value of N-terminal Pro–B-Type natriuretic peptide in patients with intermediate coronary lesions

BackgroundThe optimal treatment strategy for patients with coronary intermediate lesions, defined as diameter stenosis of 50–70%, remains a great challenge for cardiologists. Identification of potential biomarkers predictive of major adverse cardiovascular events (MACEs) risk may assist in risk stratification and clinical decision.MethodsA total of 1,187 patients with intermediate coronary lesions and available N-terminal pro-brain natriuretic peptide (NT-proBNP) levels were enrolled in the current study. A baseline NT-proBNP level was obtained. The primary endpoint was defined as MACEs, the composite endpoint of all-cause death and non-fatal myocardial infarction. A multivariate Cox regression model was used to explore the association between NT-proBNP level and MACE risk.ResultsThe mean age of the study cohort was 59.2 years. A total of 68 patients experienced MACE during a median follow-up of 6.1 years. Restricted cubic spline analysis delineated a linear relationship between the baseline NT-proBNP level and MACE risk. Both univariate and multivariate analyses demonstrated that an increased NT-proBNP level was associated with an increased risk of MACE [adjusted hazard ratio (HR) per doubling: 1.412, 95% confidence interval (CI): 1.022–1.952, p = 0.0365]. This association remains consistent in clinical meaningful subgroups according to age, sex, body mass index (BMI), and diabetes.ConclusionAn increased NT-proBNP level is associated with an increased risk of MACE in patients with intermediate coronary lesions and may serve as the potential biomarker for risk stratification and treatment decision guidance

The Overseeing Mother: Revisiting the Frontal-Pose Lady in the Wu Family Shrines in Second Century China

Located in present-day Jiaxiang in Shandong province, the Wu family shrines built during the second century in the Eastern Han dynasty (25–220) were among the best-known works in Chinese art history. Although for centuries scholars have exhaustively studied the pictorial programs, the frontal-pose female image situated on the second floor of the central pavilion carved at the rear wall of the shrines has remained a question. Beginning with the woman’s eyes, this article demonstrates that the image is more than a generic portrait (“hard motif ”), but rather represents “feminine overseeing from above” (“soft motif ”). This synthetic motif combines three different earlier motifs – the frontal-pose hostess enjoying entertainment, the elevated spectator, and the Queen Mother of the West. By creatively fusing the three motifs into one unity, the Jiaxiang artists lent to the frontal-pose lady a unique power: she not only dominated the center of the composition, but also, like a divine being, commanded a unified view of the surroundings on the lofty building, hence echoing the political reality of the empress mother’s “overseeing the court” in the second century during Eastern Han dynasty

Shortcomings of Class-level Documentation: A Survey

To better understand the shortcomings of class-level documentation, we conducted a survey of 167 experienced software developers. The survey focused on the participants' programming-related information needs and how often class-level documentation satisfies such needs

Fractal effect of hydrogen induced crack in high sulfur gathering pipeline and calculation of its propagation rate

Hydrogen induced cracking (HIC) is one of the main failure modes of high-sulfur gas field gathering pipeline network and long-distance pipeline steel. In order to clarify the mechanism and process of pipeline HIC, the cracking mode was studied. The change rule of mass concentration of hydrogen during the propagation of metal crack tip was analyzed, the dynamic model of hydrogen induced crack was corrected with consideration giving to fractal effect, and the straight crack-shear band fractal model was proposed for the propagation of hydrogen induced crack. On the basis of Gerberich's research on HIC, the shape of the fracture process zone and the crack propagation length were combined based on the hydrogenation of crack tip and the coupling factors existing during the crack propagation, the expression of the fractal rate in each stage of the hydrogen induced crack propagation was constructed, and a more reasonable mathematical model of HIC based on the fractal effect was obtained. Taking the natural gas pipeline made of 16Mn and 20 steel as example, the propagation rate of hydrogen induced crack at the base metal and the weld joint was calculated respectively, and the H2S resistance of the two materials was obtained by comparison. Therefore, the research results have certain guidance significance for the selection of high-sulfur pipeline materials

Ignition temperature and explosion pressure of suspended coal dust cloud under different conditions and suppression characteristics

Abstract The ignition and explosion processes of suspended coal dust clouds and their suppression characteristics are important aspects of dust prevention and control. To understand the ignition temperature and explosion pressure of coal dust clouds, as well as the inhibitory effect of explosion suppressants, experimental tests are conducted. The study found that during the ignition process of coal dust clouds, the optimal dust spray pressure is 20 kPa, because coal dust clouds are more likely to ignite under this condition. When the mass concentration of coal dust cloud is 500 g m−3, the maximum pressure and maximum pressure rise rate are both the highest. When Al(OH)3 is mixed with coal dust and the mass percentage is 60%, the coal dust cloud can still be ignited. When KH2PO4 is mixed with coal dust, the upper limit of the test temperature is reached when the percentage of mixture is 55%. When NH4H2PO4 is mixed with coal dust and the mass percentage is greater than 40%, the coal dust cloud can’t be ignited anymore. The suppression effect of mixing Al(OH)3 and NH4H2PO4 is not as good as that of mixing KH2PO4 and NH4H2PO4

High-resolution mapping of GDP using multi-scale feature fusion by integrating remote sensing and POI data

High-resolution spatial distribution maps of GDP are essential for accurately analyzing economic development, industrial layout, and urbanization processes. However, the currently accessible GDP gridded datasets are limited in number and resolution. Furthermore, high-resolution GDP mapping remains a challenge due to the complex sectoral structure of GDP, which encompasses agriculture, industry, and services. Meanwhile, multi-source data with high spatial resolution can effectively reflect the level of regional economic development. Therefore, we propose a multi-scale fusion residual network (Res-FuseNet) designed to estimate the GDP grid density by integrating remote sensing and POI data. Specifically, Res-FuseNet extracts multi-scale features of remote sensing and POI data relevant to different sectors. It constructs a joint representation of multi-source data through a fusion mechanism and accurately estimates GDP grid density for three sectors using residual connections. Subsequently, the high-resolution GDP grid data are obtained by correcting and overlaying grid density for each sector using county-level statistical GDP data. The 100-meter gridded GDP map of the urban agglomeration in the middle reaches of the Yangtze River in 2020 was successfully generated using this method. The experimental results confirm that Res-FuseNet outperforms machine learning models and baseline model significantly in training across different sectors and at the town-level. The R2 values for the three sectors are 0.69, 0.91, and 0.99, respectively, while the town-level evaluation results also exhibit high accuracy (R2=0.75). Res-FuseNet provides an innovative high-resolution mapping method, and the generated high-resolution GDP grid data reveal the distribution characteristics of different sector structures and fine-scale economic disparities within cities, offering robust support for sustainable development

Increased thoracic fluid content is associated with higher risk for pneumonia in patients undergoing maintenance hemodialysis

AbstractBackground Pneumonia is the most common infectious disease in patients undergoing maintenance hemodialysis (MHD). The aim of this study is to determine the possible predictive value of thoracic fluid content (TFC) for pneumonia in this population.Method Clinical data were recorded for 1412 MHD patients who were hospitalized for certain comorbidities or complications. Each patient underwent an impedance cardiography (ICG) examination before next dialysis session after admission. Patients were divided into Having-, Will-have-, and Non-pneumonia groups based on whether they had pneumonia at the time of ICG examination after the admission and within five months after the examination. Hemodynamic parameters and other clinical data were compared and analyzed.Results Patients who were going to develop pneumonia were older, and had a higher proportion of diabetes, poorer nutritional status, a higher level of inflammatory, poorer cardiac function, and more fluid volume load than those who did not develop pneumonia. Multivariate binary logistic analysis revealed that for each 1/KΩ increase in TFC and 1 increase in neutrophil-to-lymphocyte ratio (NLR), the risk of the development of pneumonia increased by 3.1% (p ˂ 0.01) and 7.2% (p = 0.035), respectively, whereas for each 1 g/L increase in hemoglobin and 1 g/L increase in serum albumin, the risk of the development of pneumonia decreased by 1.3% (p = 0.034) and 5% (p = 0.048), respectively.Conclusions TFC, NLR, hemoglobin, and serum albumin were independent risk factors for the development of pneumonia in MHD patients. Given the advantages of ICG, TFC can be used clinically as a helpful predictor of pneumonia in MHD patients