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[Display omitted] • Hydrophobic ZIF-8/SA monolithic materials were fabricated via in situ synthesis. • The cooperation of SA, PDMS, and ZIF-8 significantly enhanced adsorption capacity. • The composites displayed rapid kinetic adsorption. • The composites have remarkable absorption recyclability. Microplastics (MPs), a newly emerging class of environmental contaminants, pose a severe threat to the entire ecosystem. The development of efficient and environmentally responsible adsorbents for removing the MPs is a particularly urgent research. Herein, a kind of monolithic ZIF-8 based adsorbents featuring stable hydrophobicity and micropore-mesopore-macropore hierarchical porous structure were fabricated by in situ growth of ZIF-8 nanoparticles on sodium alginate (SA) framework, and using polydimethylsiloxane (PDMS) as a hydrophobic agent. The monolithic nature of ZIF-8/SA allowed an easy solid–liquid separation process for adsorbents from water environment compared to powdered materials. The hierarchical porous structure ensures a remarkable MPs removal performance. The ZIF-8/SA showed high adsorption capacities of 594, 585, and 282 mg/g for polymethyl methacrylate (PMMA), poly (vinylidene difluoride) (PVDF), and polyvinyl chloride (PVC) respectively, and rapid adsorption kinetic progress within 120 min. The ZIF-8/SA adsorbents also exhibited excellent stability in the presence of interfering ions, acid/alkali, and humic acid, and displayed adsorption performance of > 70 % even in actual aquatic environment such as tap water, river water, and seawater. The results of characterizations showed that the synergistic effect of electrostatic interaction, hydrogen bonding, hydrophobic force, and van der Waals force was the main adsorption mechanism. The well-designed hydrophobic ZIF-8/SA monolithic materials would be promising to rapidly remove the MPs from the water environment. [ABSTRACT FROM AUTHOR]

A novel rare earth separation system composed of lauric acid (LA) and primary ammonium (RNH 2) was studied. Compared with individual LA and RNH 2 , the mixed extraction system can significantly improve the extraction and separation ability of rare earth (RE). When LA and RNH 2 are mixed in an equal molar ratio, the synergistic coefficient for extracting Nd(III) in the system reaches 136.85. Effective separation of Nd from Co and Ni can be achieved, with the separation coefficients of 1503 and 2762 for Nd/Co and Nd/Ni, respectively. The ion association mechanism of developed extraction system can avoid the generation of saponification wastewater. Thus, the negative impact of saponification wastewater on the economy and environment can be reduced. The extraction system is simple to be prepared and easy to be stripped, which helps to reduce acid and alkali consumption. Application of this extraction system can effectively realize the separation of RE elements La, Ce, Pr, Nd and transition metals Co, Ni, Mn in nickel-metal hydride (NiMH) battery. This paper provides a new strategy for the development of ionic liquid saponification technology without saponified wastewater. [Display omitted] • LA-RNH 2 extraction system have pronounced synergistic effect on Nd. • The interaction between LA and RNH 2 provides a new strategy for saponification. • This ionic liquid saponification strategy can avoid saponification wastewater. • It has revealed application potential for the recovery of rare earth in NiMH battery. [ABSTRACT FROM AUTHOR]

NaBr-mediated "bait and switch" mechanism can promote the formation of ZnO, and thus etches carbon matrix around the N -dopants. As a result, the fully formed N -doping and intrinsic carbon defect (N/DC) coupling sites can greatly improve capacitive behavior, so an excellent cycling stability with high reversible capacity is realized. [Display omitted] Coupling sites of nitrogen-dopants and intrinsic carbon defects (N/DC) are highly attractive to improve potassium-storage capacity and cycling stability, yet it is hard to effectively construct them. Herein, a novel strategy is proposed to establish abundant N/DC sites in N -doped carbon (ZIF8/NaBr-1-900) by pyrolyzing the mixture of metal–organic framework (ZIF8)/sodium bromide (NaBr). Systematic investigations disclose that the introduced NaBr can promote the full conversion of Zn-N 4 moieties into zinc oxide (ZnO) via a "bait and switch" mechanism. Such formed endogenous ZnO can etch the carbon matrix of the confined domains around the N dopants during pyrolysis process, and meanwhile the released N -atoms from Zn-N 4 moieties can largely form edge-N. As such, these N/DC coupling sites enable the resultant carbon to have a more significant capacitive behavior related to fast K-ion migration and high structural stability, leading to 255.3 mAh/g at 2 A/g with a prolonged cycle lifespan over 2000 cycles. Moreover, the assembled K-full battery presents a high energy density of 171.2 Wh kg−1 and excellent cyclability over 5000 cycles. This NaBr-mediated endogenous ZnO domain-confined etching strategy provides a new insight into the exploration of advanced carbon anode. [ABSTRACT FROM AUTHOR]

Previous studies have indicated that EPO maintains the M2 microglia phenotype that contributes to white matter repair after ischemic stroke in young mice (2 months old). However, the underlying mechanisms that regulate microglial polarization are poorly defined. This study investigated the neuroprotective effects of nonerythropoietic mutant EPO (MEPO) on white matter and the underlying mechanism in middle-aged (9-month-old) male mice following cerebral ischemia. Middle-aged male C57 BL/6 mice were treated with MEPO (5000 IU/kg) or vehicle after middle cerebral artery occlusion (MCAO) and reperfusion. The specific inhibitor AG490 was used to block the JAK2/STAT3 pathway. Neurological function was assessed by beam walking and adhesive removal tests. Immunofluorescence staining and western blotting were used to assess the severity of white matter injury, phenotypic changes in the microglia and the expression of the signaling molecules. MEPO significantly improved neurobehavioral outcomes, alleviated brain tissue loss, and ameliorated white matter injury after MCAO compared with the vehicle group. Moreover, MEPO promoted oligodendrogenesis by shifting microglia toward M2 polarization by promoting JAK2/STAT3 activation and inhibiting the expression of C/EBPβ at 14 days after cerebral ischemia-reperfusion. However, the MEPO's effect on microglial M2 polarization and oligodendrogenesis was largely suppressed by AG490 treatment. Collectively, these data indicate that MEPO treatment improves white matter integrity after cerebral ischemia, which may be partly explained by MEPO facilitating microglia toward the beneficial M2 phenotype to promote oligodendrogenesis via JAK2/STAT3 and the C/EBPβ signaling pathway. This study provides novel insight into MEPO treatment for ischemic stroke. [ABSTRACT FROM AUTHOR]

Mass spectrometry (MS) data is susceptible to random noises and alternating baseline, posing great challenges to spectral peak detection, especially for weak peaks and overlapping peaks. Herein, an efficient peak detection algorithm combining continuous wavelet transform (CWT) and genetic algorithm-based threshold segmentation (denoted as WSTGA) for mass spectrometry was proposed. Firstly, Mexican Hat wavelet was selected as the mother wavelet by comparing the matching degree between the difference of Gaussian (DOG) and different wavelets. Subsequently, the ridges and valleys were identified from 2D wavelet coefficient matrix. Afterward, an improved threshold segmentation method, Otsu method based on genetic algorithm, was introduced to find optimal segmentation threshold and achieve better image segmentation, overcoming the deficiency of traditional Otsu method that cannot handle long-tailed unimodal histograms. Finally, the characteristic peaks were successfully identified by utilizing the ridge-valley lines in wavelet space and original spectrum. Receiver operating characteristic (ROC) curve, area under curve (AUC) and F₁ measure are used as criterions to evaluate performance of peak detection algorithms. Compared with multi-scale peak detection (MSPD) and CWT and image segmentation (CWT-IS) methods, all the results showed that WSTGA can achieve better peak detection. More importantly, the experimental results from MALDI-TOF spectra demonstrated that WSTGA can effectively detect more weak peaks and overlapping peaks while maintaining a lower false peak detection rate than MSPD and CWT-IS methods, indicating its great advantages in characteristic peak identification. • An efficient peak detection algorithm for MS using CWT and genetic algorithm-based Otsu (WSTGA) was proposed. • The genetic algorithm-based Otsu was introduced to find optimal threshold segmentation. • The ridge determination condition was improved to enhance the denoising ability of WSTGA. • WSTGA can detect more weak peaks and overlapping peaks while maintaining a lower false peak detection rate. [ABSTRACT FROM AUTHOR]

The n -dimensional locally twisted cube L T Q n is a variant of the hypercube, which possesses some properties superior to the hypercube. This paper investigates the fault-tolerant vertex-pancyclicity of L T Q n , and shows that if L T Q n ( n ⩾ 3 ) contains at most n − 3 faulty vertices and/or edges then, for any fault-free vertex u and any integer ℓ with 4 ⩽ ℓ ⩽ 2 n − f v except for 5, there is a fault-free cycle of length ℓ containing the vertex u , where f v is the number of faulty vertices. The result is optimal in some senses. [ABSTRACT FROM AUTHOR]