Field-dependent deep learning enables high-throughput whole-cell 3D super-resolution imaging.

Single-molecule localization microscopy in a typical wide-field setup has been widely used for investigating subcellular structures with super resolution; however, field-dependent aberrations restrict the field of view (FOV) to only tens of micrometers. Here, we present a deep-learning method for precise localization of spatially variant point emitters (FD-DeepLoc) over a large FOV covering the full chip of a modern sCMOS camera. Using a graphic processing unit-based vectorial point spread function (PSF) fitter, we can fast and accurately model the spatially variant PSF of a high numerical aperture objective in the entire FOV. Combined with deformable mirror-based optimal PSF engineering, we demonstrate high-accuracy three-dimensional single-molecule localization microscopy over a volume of ~180 × 180 × 5 µm3, allowing us to image mitochondria and nuclear pore complexes in entire cells in a single imaging cycle without hardware scanning; a 100-fold increase in throughput compared to the state of the art.

A Tumor-Targeting Dual-Modal imaging probe for nitroreductase in vivo.

Nitroreductase (NTR) overexpression often occurs in tumors, highlighting the significance of effective NTR detection. Despite the utilization of various optical methods for this purpose, the absence of an efficient tumor-targeting optical probe for NTR detection remains a challenge. In this research, a novel tumor-targeting probe (Cy-Bio-NO2) is developed to perform dual-modal NTR detection using near-infrared fluorescence and photoacoustic techniques. This probe exhibits exceptional sensitivity and selectivity to NTR. Upon the reaction with NTR, Cy-Bio-NO2 demonstrates a distinct fluorescence "off-on" response at 800 nm, with an impressive detection limit of 12 ng/mL. Furthermore, the probe shows on-off photoacoustic signal with NTR. Cy-Bio-NO2 has been successfully employed for dual-modal NTR detection in living cells, specifically targeting biotin receptor-positive cancer cells for imaging purposes. Notably, this probe effectively detects tumor hypoxia through dual-modal imaging in tumor-bearing mice. The strategy of biotin incorporation markedly enhances the probe's tumor-targeting capability, facilitating its engagement in dual-modal imaging at tumor sites. This imaging capacity holds substantial promise as an accurate tool for cancer diagnosis.

Correlation of coagulation states with prognosis of sudden deafness.

Prognosis of sudden deafness remains a challenge in clinics because of inhomogeneity of the disease. Here we report our retrospective study aimed to explore the value of coagulative markers including activated partial thromboplastin time (APTT), prothrombin time (PT), plasma fibrinogen (FIB), and plasma D-dimer in the prognosis of patients. The study included a total of 160 patients, of whom 92 had valid responses, 68 had invalid responses, and 68 had ineffective responses. APTT, PT, and the levels of FIB and D-dimer in serum were compared between the two groups, and their prognostic values were determined in terms of area under the curve (AUC) in receiver operating curve (ROC) analysis, sensitivity, and specificity. The correlations of APTT, PT, and FIB to degree of hearing loss were also assessed. Serum APTT and PT, FIB, and D-dimer levels were lower in patients with sudden deafness who responded poorly to treatments. ROC analysis showed that APTT, PT, FIB, and D-dimer had high AUC, sensitivity, and specificity for nonresponders, particularly when used in combination (AUC = 0.91, sensitivity = 86.76%, and specificity = 82.61%). Patients with a higher degree of hearing loss (>91 dB) also demonstrated significantly lower values of APTT and PT and higher levels of serum FIB and D-dimer than those with a lower degree of hearing loss. Our study demonstrated that APTT, PT, and serum levels of FIB and D-dimer could serve as strong predictors of sudden deafness, potentiating the use of these tests to identify patients who respond poorly to treatments.NEW & NOTEWORTHY Our retrospective study indicated that lower serum APTT and PT levels and higher fibrinogen (FIB) and D-dimer levels are characteristics associated with poor treatment responses among patients with sudden deafness. A combination of these levels had a high accuracy in identifying the nonresponders. APTT, PT, and serum levels of FIB and D-dimer could serve as strong predictors of sudden deafness, potentiating the use of these tests to identify patients who respond poorly to treatments.

Tumor-Targeting Probe for Dual-Modal Imaging of Cysteine In Vivo.

Cysteine (Cys) is a crucial biological thiol that has a vital function in preserving redox homeostasis in organisms. Studies have shown that Cys is closely related to the development of cancer. Thus, it is necessary to design an efficient method to detect Cys for an effective cancer diagnosis. In this work, a novel tumor-targeting probe (Bio-Cy-S) for dual-modal (NIR fluorescence and photoacoustic) Cys detection is designed. The probe exhibits high selectivity and sensitivity toward Cys. After reaction with Cys, both NIR fluorescence and photoacoustic signals are activated. Bio-Cy-S has been applied for the dual-modal detection of Cys levels in living cells, and it can be used to distinguish normal cells from cancer cells by different Cys levels. In addition, the probe is capable of facilitating dual-modal imaging for monitoring changes in Cys levels in tumor-bearing mice. More importantly, the excellent tumor-targeting ability of the probe greatly improves the signal-to-noise ratio of imaging. To the best of our knowledge, this is the first Cys probe to combine targeting and dual-modal imaging performance for cancer diagnosis.

The preparation, resources, applications, and future trends of nanofibers in active food packaging: a review.

Active packaging is a novel strategy for maintaining the shelf life of products and ensuring their safety, freshness, and integrity that has emerged with the consumer demand for safer, healthier, and higher quality food. Nanofibers have received a lot of attention for the application in active food packaging due to their high specific surface area, high porosity, and high loading capacity of active substances. Three common methods (electrospinning, solution blow spinning, and centrifugal spinning) for the preparation of nanofibers in active food packaging and their influencing parameters are presented, and advantages and disadvantages between these methods are compared. The main natural and synthetic polymeric substrate materials for the nanofiber preparation are discussed; and the application of nanofibers in active packaging is elaborated. The current limitations and future trends are also discussed. There have been many studies on the preparation of nanofibers using substrate materials from different sources for active food packaging. However, most of these studies are still in the laboratory research stage. Solving the issues of preparation efficiency and cost of nanofibers is the key to their application in commercial food packaging.

Electrospinning is the most used method to produce nanofibers for food packagingSolution blow and centrifugal spinning are novel for large-scale nanofiber productionA variety of natural and synthetic polymers have been used for nanofiber productionProgress has been made in the development of antimicrobial and antioxidant nanofibersEthylene removal and moisture removal nanofibers have been successfully produced.

A simple one step synthesis of magnetic-optical dual functional ZIF-8 in a sodalite phase for magnetically guided targeting bioimaging and drug delivery.

Functionalized metal-organic frameworks (MOFs) that integrate targeted tumor imaging and drug delivery are expected to significantly enhance the therapeutic efficacy of cancer. However, the complicated synthesis process has greatly limited their utilization in clinical application. Herein, a one-step simple method was used to construct novel multifunctional MOFs by co-loading doxorubicin (DOX) and Fe3O4 into the ZIF-8 with sodalite topology. DOX serves as a fluorescence imaging reagent and an anticancer drug and Fe3O4 is used as a magnetic resonance imaging and magnetic targeting anticancer reagent. The fabricated DOX/Fe3O4@ZIF-8 nanocomposite showed excellent fluorescence and magnetic resonance imaging performances in tumors. Moreover, DOX/Fe3O4@ZIF-8 can be accumulated in tumors via a magnetic targeting effect and tumor growth could be inhibited in vivo due to the release of DOX. Additionally, the apoptosis process of DOX/Fe3O4@ZIF-8 on HepG2 cells is well investigated. Overall, DOX/Fe3O4@ZIF-8 synthesized in simple one step can be used for simultaneous targeted bioimaging and cancer therapy.

Engineering Nano-Au-Based Sensor Arrays for Identification of Multiple Ni(II) Complexes in Water Samples.

Advanced techniques for nickel (Ni(II)) removal from polluted waters have long been desired but challenged by the diversity of Ni(II) species (most in the form of complexes) which could not be readily discriminated by the traditional analytical protocols. Herein, a colorimetric sensor array is developed to address the above issue based on the shift of the UV-vis spectra of gold nanoparticles (Au NPs) after interaction with Ni(II) species. The sensor array is composed of three Au NP receptors modified by N-acetyl-l-cysteine (NAC), tributylhexadecylphosphonium bromide (THPB), and the mixture of 3-mercapto-1-propanesulfonic acid and adenosine monophosphate (MPS/AMP), to exhibit possible coordination, electrostatic attraction, and hydrophobic interaction toward different Ni(II) species. Twelve classical Ni(II) species were selected as targets to systematically demonstrate the applicability of the sensor array under various conditions. Multiple interactions with Ni(II) species were evidenced to trigger the diverse Au NP aggregation behaviors and subsequently produce a distinct colorimetric response toward each Ni(II) species. With the assistance of multivariate analysis, the Ni(II) species, either as the sole compound or as mixtures, can be unambiguously discriminated with high selectivity in simulated and real water samples. Moreover, the sensor array is very sensitive with the detection limit in the range of 4.2 to 10.5 µM for the target Ni(II) species. Principal component analysis signifies that coordination dominates the response of the sensor array toward different Ni(II) species. The accurate Ni(II) speciation provided by the sensor array is believed to assist the rational design of specific protocols for water decontamination and to shed new light on the development of convenient discrimination methods for other toxic metals of concern.

Peroxymonosulfate Activation by Fe(III)-Picolinate Complexes for Efficient Water Treatment at Circumneutral pH: Fe(III)/Fe(IV) Cycle and Generation of Oxyl Radicals.

Improving the reactivity of Fe(III) for activating peroxymonosulfate (PMS) at circumneutral pH is critical to propel the iron-activated PMS processes toward practical wastewater treatment but is yet challenging. Here we employed the complexes of Fe(III) with the biodegradable picolinic acid (PICA) to activate PMS for degradation of selected chlorinated phenols, antibiotics, pharmaceuticals, herbicides, and industrial compounds at pH 4.0-6.0. The FeIII-PICA complexes greatly outperformed the ligand-free Fe(III) and other Fe(III) complexes of common aminopolycarboxylate ligands. In the main activation pathway, the key intermediate is a peroxymonosulfate complex, tentatively identified as PICA-FeIII-OOSO3-, which undergoes O-O homolysis or reacts with FeIII-PICA and PMS to yield FeIV=O and SO4•- without the involvement of commonly invoked Fe(II). PICA-FeIII-OOSO3- can also react directly with certain compounds (chlorophenols and sulfamethoxazole). The relative contributions of PICA-FeIII-OOSO3-, FeIV=O, and SO4•- depend on the structure of target compounds. This work sets an eligible example to enhance the reactivity of Fe(III) toward PMS activation by ligands and sheds light on the previously unrecognized role of the metal-PMS complexes in directing the catalytic cycle and decontamination as well.

Synergistic benefits of Funneliformis mosseae and Bacillus paramycoides: Enhancing soil health and soybean tolerance to root rot disease.

To explore the response of soil metabolite composition to soybean disease, the effect of the combined inoculation of arbuscular mycorrhizal fungi (AMF) and plant growth-promoting bacteria on soybean root rot caused by Fusarium oxysporum was studied. A factorial completely randomized design with three factors (AMF, Bacillus. paramycoides, and rot disease stress) was conducted, and eight treatments, including normal groups and stress groups, were performed using pot experiments. GC‒MS and enzymatic assays were used to evaluate the soil factors and soybean growth indicators. The results showed that there were significant differences in the composition of metabolites among the different treatment groups, and 23 metabolites were significantly related to soybean biomass. The combined inoculation of Funneliformis mosseae and Bacillus paramycoides resulted in a significant reduction in harmful soil metabolites associated with root rot disease, such as ethylbenzene and styrene. This reduction in metabolites contributed to improving soil health, as evidenced by enhanced soybean defence enzyme activities and microbial activity, and ß-1,3-glucanase, chitinase and phenylalanine ammonia-lyase activities were improved to alleviate plant rhizosphere stress. Furthermore, soybean plants inoculated with the synergistic treatments exhibited reduced root rot disease severity and improved growth indicators compared to control plants. Plant height, root dry weight (RDW), and shoot and root fresh weight (SRFW) were improved by 4.18-53.79%, and the AM fungal colonization rate was also improved under stress. The synergistic application of Funneliformis mosseae and Bacillus paramycoides can effectively enhance soil health by inhibiting the production of harmful soil metabolites and improving soybean tolerance to root rot disease. This approach holds promise for the sustainable management of soil-borne diseases in soybean cultivation.

Associations of dichlorophenol with metabolic syndrome based on multivariate-adjusted logistic regression: a U.S. nationwide population-based study 2003-2016.

BACKGROUND: Para-dichlorobenzene (p-DCB) exposure associated with oxidative stress has indeed raised public concerns. However, whether p-DCB is linked with metabolic syndrome (MetS) remains unclear. We hypothesized that higher exposure to p-DCB would be linked with a higher risk of MetS in the U.S population. This study aimed to examine the associations of exposure to p-DCB with MetS prevalence. METHODS: We included 10,428 participants (5,084 men and 5,344 women), aged ≥ 20 years, from the National Health and Nutrition Examination Survey (2003-2016). The cases of MetS were diagnosed by NCEP/ATPIII. Logistic regression models were conducted to calculate the odds ratios (ORs) and 95% confidence intervals (CIs) of MetS prevalence. Moreover, the mix associations of p-DCB metabolites were assessed using quantile sum (WQS) regression and quantile g-computation (qgcomp) methods. RESULTS: We documented 2,861 (27.1%) MetS cases. After adjustment for the potential risk factors, the ORs (95% CI) of MetS prevalence across the quartile of urinary 2,5-dichlorophenol (2,5-DCP) were 1.09 (0.93-1.28), 1.22 (1.00-1.49), and 1.34 (1.04-1.73). Moreover, 2,5 DCP is significantly associated with a higher prevalence of abdominal obesity [ORQ4vsQ1 (95% CI): 1.23 (1.03-1.48)]. The WQS and qgcomp index also showed significant associations between p-DCB metabolites and MetS. Moreover, we further examined that 2,5 DCP was correlated with higher systolic blood pressure (r = 0.022, P = 0.027), waist circumference (r = 0.099, P < 0.001), and glycohemoglobin (r = 0.027, P = 0.008) and a lower high density cholesterol (r = -0.059, P < 0.001). In addition, the significant positive associations between 2,5 DCP and MetS were robust in the subgroup and sensitivity analyses. CONCLUSION: These findings indicated that increased urinary p-DCB concentration, especially 2,5 DCP, had a higher MetS prevalence. These results should be interpreted cautiously and further research is warranted to validate our findings.

High Spatial and Temporal Resolution NIR-IIb Gastrointestinal Imaging in Mice.

Conventional biomedical imaging modalities, including endoscopy, X-rays, and magnetic resonance, are invasive and insufficient in spatial and temporal resolutions for gastrointestinal (GI) tract imaging to guide prognosis and therapy. Here we report a noninvasive method based on lanthanide-doped nanocrystals with ∼1530 nm fluorescence in the near-infrared-IIb window (NIR-IIb, 1500-1700 nm). The rational design of nanocrystals have led to an absolute quantum yield (QY) up to 48.6%. Further benefiting from the minimized scattering through the NIR-IIb window, we enhanced the spatial resolution to ∼1 mm in GI tract imaging, which is ∼3 times higher compared with the near-infrared-IIa (NIR-IIa, 1000-1500 nm) method. The approach also realized a high temporal resolution of 8 frames per second; thus the moment of mice intestinal peristalsis can be captured. Furthermore, with a light-sheet imaging system, we demonstrated a three-dimensional (3D) imaging on the GI tract. Moreover, we successfully translated these advances to diagnose inflammatory bowel disease.

[Establishment of a PCR-SSP method for the simultaneous amplification and identification of the presence of KIR genes].

OBJECTIVE: To develop a polymerase chain reaction-sequence specific primer (PCR-SSP) method for simultaneous amplification and identification of the KIR genes among Chinese population. METHODS: Peripheral blood samples from 132 healthy donors who had given blood at Shenzhen Blood Center from January 2015 to November 2015 were selected as the study subjects. Based on the polymorphism and single nucleotide polymorphism (SNP) information of high-resolution KIR alleles in the Chinese population and the IPD-KIR database, specific primers were designed to amplify all the 16 KIR genes and the 2DS4-Normal and 2DS4-Deleted subtypes. The specificity of each pair of PCR primers was verified by using samples with known KIR genotypes. During PCR amplification of the KIR gene, co-amplification the fragment of human growth hormone (HGH) gene by multiplex PCR was used as the internal control to prevent false negative results. A total of 132 samples with known KIR genotypes were randomly selected for blind inspection to verify the reliability of the developed method. RESULTS: The designed primers can specifically amplify the corresponding KIR genes, with clear and bright bands for the internal control and KIR genes. The results of detection are fully consistent with the known results. CONCLUSION: The KIR PCR-SSP method established in this study can yield accurate results for the identification of the presence of KIR genes.

Ratiometric 4Pi single-molecule localization with optimal resolution and color assignment.

4Pi single-molecule localization microscopy (4Pi-SMLM) with two opposing objectives achieves sub-10 nm isotropic 3D resolution when as few as 250 photons are collected by each objective. Here, we develop a new ratiometric multi-color imaging strategy for 4Pi-SMLM that employs the intrinsic multi-phase interference intensity without increasing the complexity of the system and achieves both optimal 3D resolution and color separation. By partially linking the photon parameters between channels with an interference difference of π during global fitting of the multi-channel 4Pi single-molecule data, we show via simulated data that the loss of localization precision is minimal compared with the theoretical minimum uncertainty, the Cramer-Rao lower bound.

ERK is involved in the regulation of CpG ODN 2395 on the expression levels of anti-lipopolysaccharide factors in Chinese mitten crab, Eriocheir sinensis.

CpG oligodeoxynucleotides (ODN), as an effective adjuvant or immunopotentiator, activate the immune system and induce various immune responses. Recently, it has also been reported that high dose of CpG ODN can lead to immunosuppression. However, the underlying mechanism of CpG ODN-mediated immune response remains largely unknown in invertebrates. In the present study, the role of ERK in regulating expression levels of anti-lipopolysaccharide factors (ALFs) induced by different doses of CpG ODN 2395 was analyzed in Chinese mitten crab, Eriocheir sinensis. The mRNA expression levels of EsALFs (EsALF1, EsALF2 and EsALF3) and EsERK in haemocytes were observed to increase from 6 h to 48 h post low doses of CpG ODN 2395 (0.5 µg and 2.5 µg) stimulation, while they were suppressed after high dose of CpG ODN 2395 (12.5 µg) injection. Meanwhile, the phosphorylation levels of ERK in haemocytes were significantly promoted after low doses of CpG ODN 2395 injection, and a reduce level of ERK phosphorylation was observed after high dose of CpG ODN 2395 injection. Further investigation showed that the expression levels of EsALFs induced by CpG ODN 2395 were markedly down-regulated after knocking down the expression of EsERK. Similarly, the EsALFs mRNA expression were also inhibited post different doses of CpG ODN 2395 stimulation in PD98059 (ERK inhibitor) injection crabs. These results collectively suggest that ERK is involved in regulating the expression level of EsALFs induced by different dose of CpG ODN 2395 in Chinese mitten crab, which contribute to the understanding of the regulation of CpG ODN involving in immune response in crustaceans.

Trimetallic metal-organic frameworks (Fe, Co, Ni-MOF) derived as efficient electrochemical determination for ultra-micro imidacloprid in vegetables.

The excessive use of imidacloprid in agricultural production leads to a large number of residues that seriously threaten human health. Therefore, the detection of imidacloprid has become very important. But how to quantitatively detect imidacloprid at ultra-low levels is the main challenges. In this work, trimetallic metal-organic frameworks Fe, Co, Ni-MOF (FCN-MOF) isin situprepared on nickel foam (NF) and then used to make an electrochemical sensor in the detection of imidacloprid. FCN-MOF exhibits the characteristics of ultra-micro concentration detection for imidacloprid with high specific surface area and rich active metal centers. The high conductivity and 3D skeleton structure of the NF electrode enhance the contact site with imidacloprid and promote the transmission of electrons efficiently. All results show that the prepared electrochemical sensor has the advantages of ultra-low detection limits (0.1 pM), wide linear detection ranges (1-5 × 107pM) and good sensitivity (132.91µA pM‒1cm‒2), as well as good reproducibility, excellent anti-interference ability, and fantastic stability. Meanwhile, the electrochemical sensor is used to determine imidacloprid in lettuce, tomato, and cucumber samples with excellent recovery (90%-102.7%). The novel electrochemical sensor is successfully applied to the ultra-micro detection of imidacloprid in vegetables, which provides a new way for the efficient monitoring of imidacloprid in agriculture.

Interaction between Organic Compounds and Catalyst Steers the Oxidation Pathway and Mechanism in the Iron Oxide-Based Heterogeneous Fenton System.

In the past decades, extensive efforts have been devoted to the mechanistic understanding of various heterogeneous Fenton reactions. Nevertheless, controversy still remains on the oxidation mechanism/pathway toward different organic compounds in the classical iron oxide-based Fenton reaction, largely because the role of the interaction between the organic compounds and the catalyst has been scarcely considered. Here, we revisited the classic heterogeneous ferrihydrite (Fhy)/H2O2 system toward different organic compounds on the basis of a series of degradation experiments, alcohol quenching experiments, theoretical modeling, and intermediate analysis. The Fhy/H2O2 system exhibited highly selective oxidation toward the group of compounds that bear carboxyl groups, which tend to complex with the surface ≡Fe(III) sites of the Fhy catalyst. Such interaction results in a nonradical inner sphere electron transfer process, which seizes one electron from the target compound and features negligible inhibition by the radical quencher. In contrast, for the oxidation of organic compounds that could not complex with the catalyst, the traditional HO· process makes the main contribution, which proceeds via hydroxyl addition reaction and could be readily suppressed by the radical quencher. This study implies that the interaction between the organic compounds and the catalyst plays a decisive role in the oxidation pathway and mechanism of the target compounds and provides a holistic understanding on the iron oxide-based heterogeneous Fenton system.

Mn(II) Acceleration of the Picolinic Acid-Assisted Fenton Reaction: New Insight into the Role of Manganese in Homogeneous Fenton AOPs.

The homogeneous Fe-catalyzed Fenton reaction remains an attractive advanced oxidation process for wastewater treatment, but sustaining the Fe(III)/Fe(II) redox cycle at a convenient pH without the costly input of energy or reductants remains a challenge. Mn(II) is known to accelerate the Fenton reaction, yet the mechanism has never been confidently established. We report a systematic kinetic and spectroscopic investigation into Mn(II) acceleration of atrazine or 2,4,6-trichlorophenol degradation by the picolinic acid (PICA)-assisted Fenton reaction at pH 4.5-6.0. Mn(II) accelerates Fe(III) reduction, superoxide radical (HO2•/O2•-) formation, and hydroxyl radical (HO•) formation. A Mn(II/III)-H2O2 redox cycle as an independent source of reactive oxygen species, as proposed in the literature, is shown to be insignificant. Rather, Mn(II) assists by participating directly and catalytically in the Fe(III)/Fe(II) redox cycle. Initially, Mn(II) (as MnII(PICA)+) complexes with a ferric hydroperoxo species, PICA-FeIII-OOH. The resulting binuclear complex undergoes intramolecular electron transfer to give Fe(II), which later generates HO• from H2O2, plus MnO2+, which later decomposes to HO2•/O2•- (an Fe(III) reductant) and Mn(II), completing the catalytic cycle. This scheme may apply to other Fenton-type systems that go through an FeIII-OOH intermediate. The findings here will inform the design of practical and sustainable Fenton-based AOPs employing Mn(II) in combination with chelating agents.

Self-Enhanced Selective Oxidation of Phosphonate into Phosphate by Cu(II)/H2O2: Performance, Mechanism, and Validation.

Phosphonate is an important category of highly soluble organophosphorus in contaminated waters, and its oxidative transformation into phosphate is usually a prerequisite step to achieve the in-depth removal of the total phosphorus. Currently, selective oxidation of phosphonate into phosphate is urgently desired as conventional advanced oxidation processes suffer from severe matrix interferences. Herein, we employed 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP) as a model phosphonate and demonstrated its efficient and selective oxidation by the Cu(II)/H2O2 process at alkaline pH. In the presence of trace Cu(II) (0.020 mM), 90.8% of HEDP (0.10 mM) was converted to phosphate by H2O2 in 30 min at pH 9.5, whereas negligible conversion was observed by UV/H2O2 or a Fenton reaction (pH = 3.0). The oxidation of HEDP by Cu(II)/H2O2 was insignificantly affected by natural organic matters (10.0 mg TOC/L) and various anions including chloride, sulfate, and nitrate (10.0 mM). The complexation of Cu(II) with HEDP coupling Cu(III) produced in situ enabled an intramolecular electron transfer process, which features high selective oxidation. Selective degradation of HEDP was further validated by adding stoichiometric H2O2 into an industrial effluent, where the existing Cu(II) could serve as the catalyst. This study also provides a successful case to trigger selective oxidation of trace pollutants of concern upon synergizing with the nature of the contaminated water.

Singlet oxygen mediated iron-based Fenton-like catalysis under nanoconfinement.

For several decades, the iron-based Fenton-like catalysis has been believed to be mediated by hydroxyl radicals or high-valent iron-oxo species, while only sporadic evidence supported the generation of singlet oxygen (1O2) in the Haber-Weiss cycle. Herein, we report an unprecedented singlet oxygen mediated Fenton-like process catalyzed by ∼2-nm Fe2O3 nanoparticles distributed inside multiwalled carbon nanotubes with inner diameter of ∼7 nm. Unlike the traditional Fenton-like processes, this delicately designed system was shown to selectively oxidize the organic dyes that could be adsorbed with oxidation rates linearly proportional to the adsorption affinity. It also exhibited remarkably higher degradation activity (22.5 times faster) toward a model pollutant methylene blue than its nonconfined analog. Strikingly, the unforeseen stability at pH value up to 9.0 greatly expands the use of Fenton-like catalysts in alkaline conditions. This work represents a fundamental breakthrough toward the design and understanding of the Fenton-like system under nanoconfinement, might cause implications in other fields, especially in biological systems.

Characterizing the Semi-Volatile Organic Compounds in Runoff from Roads and Other Impervious Surfaces in a Suburban Area of Beijing.

Stormwater runoff samples were collected from five different land use sites (gas station, city road, campus, park, and residential) in a precipitation event on May 22nd, 2017, from a small suburban area (5 km × 2 km) of the city of Beijing, China. There were 72 types of semi-volatile organic compounds (SVOCs) found in these runoff samples, including 33 types of monocyclic aromatic hydrocarbons (MAHs), 22 types of polycyclic aromatic hydrocarbons (PAHs), 6 types of phthalate esters (PAEs), 9 types of pesticides and 2 types of polychlorinated biphenyls (PCBs). Especially, 26 types of SVOCs (7 MAHs, 9 PAHs, 5 PAEs, and 5 pesticides) were detected in all water samples. SVOCs concentrations were higher in the samples from gas station and city road, and lower in runoff from campus, park and residential sites. The change in the ratio of anthracene to anthracene plus phenanthrene (ANT/(ANT + PHE)) in this study, reflected the importance of PAH source and land use. Di-2-ethylhexyl phthalate (DEHP) and di-n-butyl phthalate, are two of the phthalate esters 100% detected in the runoff samples. The city road runoff DEHP concentrations recorded the highest values (> 6000 ng/L), however, were still less than those wastewater DEHP pollutants measured in developed countries (e.g. UK, Canada, Finland, etc.). One-way ANOVA analysis in this study, showed that land use could significantly influence 23 SVOCs in the runoff samples, whereas the runoff SVOCs in different precipitation period showed no statistical changes in the five sites, and presented a general temporal trends "high (beginning)-low (middle period)-little raising (ending)". The findings in this study could be used in municipal management of wastewater collection and treatment.