Transition metal (TM)‐based bimetallic spinel oxides can efficiently activate peroxymonosulfate (PMS) presumably attributed to enhanced electron transfer between TMs, but the existing model cannot ...fully explain the efficient TM redox cycling. Here, we discover a critical role of TM−O covalency in governing the intrinsic catalytic activity of Co3−xMnxO4 spinel oxides. Experimental and theoretical analysis reveals that the Co sites significantly raises the Mn valence and enlarges Mn−O covalency in octahedral configuration, thereby lowering the charge transfer energy to favor MnOh–PMS interaction. With appropriate MnIV/MnIII ratio to balance PMS adsorption and MnIV reduction, the Co1.1Mn1.9O4 exhibits remarkable catalytic activities for PMS activation and pollutant degradation, outperforming all the reported TM spinel oxides. The improved understandings on the origins of spinel oxides activity for PMS activation may inspire the development of more active and robust metal oxide catalysts.
The Mn−O covalency was enlarged by the Co sites mainly in the octahedral configuration, which results in a decreased charge transfer energy to favor Mn–PMS interaction and enhance MnIV reduction to boost PMS activation activity of Co‐Mn spinel oxides.
Background
Most cases of ipsilateral breast tumor recurrence (IBTR) after breast‐conserving surgery (BCS) involve small tumors. Although a few guidelines recommend mastectomy, several patients prefer ...repeat BCS (re‐BCS). This study aimed to compare re‐BCS and mastectomy in terms of prognosis in patients with IBTR and to identify candidates for re‐BCS.
Methods
The data of patients with small IBTR between 1999 and 2015 were obtained from the Surveillance, Epidemiology, and End Results database. The outcomes of interest were overall survival (OS) and breast cancer–specific survival (BCSS). Multivariable Cox proportional hazards regression models and propensity score matching were applied.
Results
Of the 3648 patients with IBTR, 2831 (77.6%) underwent mastectomy and 817 (22.4%) underwent re‐BCS. The multivariate Cox model showed that re‐BCS was associated with a worse OS (hazard ratio HR, 1.342; 95% confidence interval CI, 1.084–1.663) and BCSS (HR, 1.454; 95% CI, 1.004–2.105) compared with mastectomy. The omission of radiation after re‐BCS was associated with worse survival overall and especially in patients with estrogen receptor (ER)‐negative IBTR (HR, 1.384; 95% CI, 1.110–1.724; and HR, 1.577; 95% CI, 1.075–2.314, respectively). No statistically significant differences were observed in the OS and BCSS between re‐BCS with radiation and mastectomy. Subgroup analysis indicated that the surgical approach was not an independent factor for survival in the ER‐positive patients with IBTR.
Conclusions
Re‐BCS should be considered with caution in patients with small IBTR. However, a positive ER status can be an important factor for choosing re‐BCS, and radiation therapy may improve oncological safety after re‐BCS.
Lay summary
Repeat breast‐conserving surgery (re‐BCS) was investigated to determine if it is safe for patients with small ipsilateral breast tumor recurrence (IBTR) after breast‐conserving surgery (BCS).
This population‐based cohort study included 2831 patients with small IBTR. Re‐BCS was associated with a worse overall survival and breast cancer–specific survival compared with mastectomy.
Further analysis found that the IBTR estrogen receptor status was an important basis for choosing re‐BCS, and radiation may improve oncological safety after re‐BCS.
Repeat breast conservation (re‐BCS) should be considered with caution in patients with small ipsilateral breast tumor recurrence. A positive estrogen receptor status and radiation can be important factors for choosing re‐BCS.
Agricultural food production is at the base of food and fodder, with fertilization having fundamentally and continuously increased crop yield over the last decades. The performance of crops is ...intimately tied to their microbiome as they together form holobionts. The importance of the microbiome for plant performance is, however, notoriously ignored in agricultural systems as fertilization disconnects the dependency of plants for often plant-beneficial microbial processes. Moreover, we lack a holistic understanding of how fertilization regimes affect the soil microbiome. Here, we examined the effect of a 2-year fertilization regime (no nitrogen fertilization control, nitrogen fertilization, and nitrogen fertilization plus straw amendment) on entire soil microbiomes (bacteria, fungi, and protist) in three common agricultural soil types cropped with maize in two seasons.
We found that the application of nitrogen fertilizers more strongly affected protist than bacterial and fungal communities. Nitrogen fertilization indirectly reduced protist diversity through changing abiotic properties and bacterial and fungal communities which differed between soil types and sampling seasons. Nitrogen fertilizer plus straw amendment had greater effects on soil physicochemical properties and microbiome diversity than nitrogen addition alone. Moreover, nitrogen fertilization, even more together with straw, increased soil microbiome network complexity, suggesting that the application of nitrogen fertilizers tightened soil microbiomes interactions.
Together, our results suggest that protists are the most susceptible microbiome component to the application of nitrogen fertilizers. As protist communities also exhibit the strongest seasonal dynamics, they serve as the most sensitive bioindicators of soil changes. Changes in protist communities might have long-term effects if some of the key protist hubs that govern microbiome complexities as top microbiome predators are altered. This study serves as the stepping stone to promote protists as promising agents in targeted microbiome engineering to help in reducing the dependency on exogenous unsustainably high fertilization and pesticide applications.
Although 5-methylcytosine (m
C) is a widespread modification in RNAs, its regulation and biological role in pathological conditions (such as cancer) remain unknown. Here, we provide the ...single-nucleotide resolution landscape of messenger RNA m
C modifications in human urothelial carcinoma of the bladder (UCB). We identify numerous oncogene RNAs with hypermethylated m
C sites causally linked to their upregulation in UCBs and further demonstrate YBX1 as an m
C 'reader' recognizing m
C-modified mRNAs through the indole ring of W65 in its cold-shock domain. YBX1 maintains the stability of its target mRNA by recruiting ELAVL1. Moreover, NSUN2 and YBX1 are demonstrated to drive UCB pathogenesis by targeting the m
C methylation site in the HDGF 3' untranslated region. Clinically, a high coexpression of NUSN2, YBX1 and HDGF predicts the poorest survival. Our findings reveal an unprecedented mechanism of RNA m
C-regulated oncogene activation, providing a potential therapeutic strategy for UCB.
Imbalanced classification has drawn considerable attention in the statistics and machine learning literature. Typically, traditional classification methods often perform poorly when a severely skewed ...class distribution is observed, not to mention under a high‐dimensional longitudinal data structure. Given the ubiquity of big data in modern health research, it is expected that imbalanced classification in disease diagnosis may encounter an additional level of difficulty that is imposed by such a complex data structure. In this article, we propose a nonparametric classification approach for imbalanced data in longitudinal and high‐dimensional settings. Technically, the functional principal component analysis is first applied for feature extraction under the longitudinal structure. The univariate exponential loss function coupled with group LASSO penalty is then adopted into the classification procedure in high‐dimensional settings. Along with a good improvement in imbalanced classification, our approach provides a meaningful feature selection for interpretation while enjoying a remarkably lower computational complexity. The proposed method is illustrated on the real data application of Alzheimer's disease early detection and its empirical performance in finite sample size is extensively evaluated by simulations.
Metal binding to microbial extracellular polymeric substances (EPS) greatly influences the distribution of heavy metals in microbial aggregates, soil and aquatic systems in nature. In this work, the ...thermodynamic characteristics of the binding between aqueous metals (with copper ion as an example) and EPS of activated sludge were investigated. Isothermal titration calorimetry was employed to estimate the thermodynamic parameters for the binding of Cu2+ onto EPS, while three-dimensional excitation-emission matrix (EEM) fluorescence spectroscopy with parallel factor analysis was used for quantifying the complexation of Cu2+ with the EPS. The binding mechanisms were further explored by X-ray absorption fine structure (XAFS) and Fourier transform infrared (FTIR) spectroscopy analysis. The results show that the proteins and humic substances in EPS were both strong ligands for Cu2+. The binding capacity N, binding constant K, binding enthalpy ΔH were calculated as 5.74 × 10−2 mmol/g, 2.18 × 105 L/mol, and −11.30 kJ/mol, respectively, implying that such a binding process was exothermic and thermodynamically favorable. The binding process was found to be driven mainly by the entropy change of the reaction. A further investigation shows that Cu2+ bound with the oxygen atom in the carboxyl groups in the EPS molecules of activated sludge. This study facilitates a better understanding about the roles of EPS in protecting microbes against heavy metals.
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► Thermodynamic characteristics of binding of Cu2+ to EPS are investigated. ► The binding process is exothermic and thermodynamically favorable. ► Cu2+ binds with the O atom in the carboxyl groups in EPS.
Azo dyes are a class of recalcitrant organic pollutants causing severe environmental pollution. For their biodecolorization, the azo reductase system was considered as the major molecular basis in ...bacteria. However, the intracellular localization of azo reductase limits their function for efficient azo dye decolorization. This limitation may be circumvented by electrochemically active bacteria (EAB) which is capable of extracellular respiration. To verify the essential role of extracellular respiration in azo dye decolorization, Geobacter sulfurreducens PCA, a model EAB, was used for the bioreduction of methyl orange (MO), a typical azo dye. G. sulfurreducens PCA efficiently reduced MO into amines. Kinetic results showed that G. sulfurreducens PCA had the highest decolorization efficiency among the currently known MO reducing bacteria. Electrons from acetate oxidization by this strain were transferred by the respiratory chain to MO. The mass and electron balances, fluorescent probing and proteinase K treatment experimental results indicate that the biodecolorization of MO by G. sulfurreducens PCA is an exclusive extracellular process. OmcB, OmcC and OmcE were identified as the key outer-membrane proteins for the extracellular MO reduction. This work deepens our understanding of EAB physiology and is useful for the decontamination of environments polluted with azo dyes. The contribution of extracellular respiration to pollutants reduction will broaden the environmental applications of EAB.
Removal of organic micropollutants from water through advanced oxidation processes (AOPs) is hampered by the excessive input of energy and/or chemicals as well as the large amounts of residuals ...resulting from incomplete mineralization. Herein, we report a new water purification paradigm, the direct oxidative transfer process (DOTP), which enables complete, highly efficient decontamination at very low dosage of oxidants. DOTP differs fundamentally from AOPs and adsorption in its pollutant removal behavior and mechanisms. In DOTP, the nanocatalyst can interact with persulfate to activate the pollutants by lowering their reductive potential energy, which triggers a non-decomposing oxidative transfer of pollutants from the bulk solution to the nanocatalyst surface. By leveraging the activation, stabilization, and accumulation functions of the heterogeneous catalyst, the DOTP can occur spontaneously on the nanocatalyst surface to enable complete removal of pollutants. The process is found to occur for diverse pollutants, oxidants, and nanocatalysts, including various low-cost catalysts. Significantly, DOTP requires no external energy input, has low oxidant consumption, produces no residual byproducts, and performs robustly in real environmental matrices. These favorable features render DOTP an extremely promising nanotechnology platform for water purification.
Exploring effective electrocatalysts for oxygen evolution reaction (OER) is a crucial requirement of many energy storage and conversion systems, involving fuel cells, water splitting, and metal–air ...batteries. Herein, a heterogeneity metal‐organic framework (MOF) is prepared by the assembling of metals, terephthalic (A) and 2‐aminoterephthalic ligands (B), defined as A2.7B‐MOF‐FeCo1.6. More importantly, A2.7B‐MOF‐FeCo1.6 exhibits excellent OER activity with an ultralow overpotential of 288 mV at 10 mA cm−2 and a Tafel slope of 39 mV dec−1. The high electrocatalytic performance for OER is attributed to the optimized electronic structure of the intrinsic catalytic center in MOFs via the engineering of the metal node and linkers. The work offers not only a benchmark for pure MOFs in electrocatalysis but also a new efficient strategy to improve electrocatalytic performance by electronic structure engineering of catalytic active centers in MOFs.
A heterogeneity MOF A2.7B‐MOF‐FeCo1.6 is prepared by structurally tailoring metal nodes and organic linkers. It can serve as an efficient electrocatalyst with superior oxygen evolution reaction activity owing to modulations in the electronic structure of the catalytic center.
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