Robust Activity and Stability of P-Doped Fe-Carbon Composites Derived from MOF for Bromate Reduction

Iron-based materials are effective for the reductive removal of the disinfection byproduct bromate in water, while the construction of highly stable and active Fe-based materials with wide pH adaptability remains greatly challenging. In this study, highly dispersed iron phosphide-decorated porous carbon (Fe2P(x)@P(z)NC-y) was prepared via the thermal hydrolysis of Fe@ZIF-8, followed by phosphorus doping (P-doping) and pyrolysis. The reduction performances of Fe2P(x)@P(z)NC-y for bromate reduction were evaluated. Characterization results showed that the Fe, P, and N elements were homogeneously distributed in the carbonaceous matrix. P-doping regulated the coordination environment of Fe atoms and enhanced the conductivity, porosity, and wettability of the carbonaceous matrix. As a result, Fe2P(x)@P(1.0)NC-950 exhibited enhanced reactivity and stability with an intrinsic reduction kinetic constant (kint) 1.53-1.85 times higher than Fe(x)@NC-950 without P-doping. Furthermore, Fe2P(0.125)@P(1.0)NC-950 displayed superior reduction efficiency and prominent stability with very low Fe leaching (4.53-22.98 μg L-1) in a wide pH range of 4.0-10.0. The used Fe2P(0.125)@P(1.0)NC-950 could be regenerated by phosphating, and the regenerated Fe2P(0.125)@P(1.0)NC-950 maintained 85% of its primary reduction activity after five reuse cycles. The study clearly demonstrates that Fe2P-decorated porous carbon can be applied as a robust and stable Fe-based material in aqueous bromate reduction.

Multiple-Emitting Luminescent Metal-Organic Framework as an Array-on-a-MOF for Rapid Screening and Discrimination of Nitroaromatics

Fluorescence array technologies have attracted great interest in the sensing field because of their high sensitivity, low cost, and capability of multitarget detection. However, traditional array sensing relies on multiple independent sensors and thus often requires time-consuming and laborious measurement processes. Herein, we introduce a novel fluorescence array strategy of the array-on-a-metal-organic framework (MOF), which integrates multiple array elements into a single MOF matrix to achieve facile sensing and discrimination of multiple target analytes. As a proof-of-concept system, we constructed a luminescent MOF containing three different emitting channels, including a lanthanide ion (europium/Eu3+, red emission), a fluorescent dye (7-hydroxycoumarin-4-acetic acid/HCAA, blue emission), and the MOF itself (UiO-66-type MOF, blue-violet emission). Five structurally similar nitroaromatic compounds (NACs) were chosen as the targets. All three channels of the array-on-a-MOF displayed rapid and stable fluorescence quenching responses to NACs (response equilibrium achieved within 30 s). Different responses were generated for each channel against each NAC due to the various quenching mechanisms, including photoinduced electron transfer, energy competition, and the inner filter effect. Using linear discriminant analysis, the array-on-a-MOF successfully distinguished the five NACs and their mixtures at varying concentrations and demonstrated good sensitivity to quantify individual NACs (detect limit below the advisory concentration in drinking water). Moreover, the array also showed feasibility in the sensing and discrimination of multiple NACs in real water samples. The proposed "array-on-a-MOF" strategy simplifies multitarget discrimination procedures and holds great promise for various sensing applications.

Establishment of an Efficient Genetic Transformation System in Sanghuangporus baumii

(1) Background: Sanghuangporus baumii, a valuable medicinal fungus, has limited studies on its gene function due to the lack of a genetic transformation system. (2) Methods: This study aimed to establish an efficient Agrobacterium tumefaciens-mediated transformation (ATMT) system for S. baumii. This study involved cloning the promoter (glyceraldehyde-3-phosphate dehydrogenase, gpd) of S. baumii, reconstructing the transformation vector, optimizing the treatment of receptor tissues, and inventing a new method for screening positive transformants. (3) Results: The established ATMT system involved replacing the CaMV35S promoter of pCAMBIA-1301 with the gpd promoter of S. baumii to construct the pCAMBIA-SH-gpd transformation vector. The vectors were then transferred to A. tumefaciens (EHA105) for infection. This study found that the transformation efficiency was higher in the infection using pCAMBIA-SH-gpd vectors than using pCAMBIA-1301 vectors. The mycelia of S. baumii were homogenized for 20 s and collected as the genetic transformation receptor. After 20 min of co-culture and 48 h of incubation in 15 mL PDL medium at 25 °C, new colonies grew. (4) Conclusions: These colonies were transferred to PDA medium (hygromycin 4 μg/mL, cefotaxime 300 μg/mL), and the transformation efficiency was determined to be 33.7% using PCR.

Efficient Catalytic Oxidation of Ethylene at 0 °C on an in Situ Carbon Modified Pt Catalyst Supported on SBA-15

The design of efficient catalysts for catalytic ethylene (C2H4) oxidation is of crucial importance for extending the shelf life of fruits and vegetables. Herein, a carbon modified SBA-15 supported Pt catalyst (Pt/CSBA-15) was prepared in situ by a facile solid phase grinding-infiltration-inert atmosphere calcination method. Characterization results reveal that in the Pt/CSBA-15 catalysts thin carbon layers are successfully formed in the hexagonal pores of SBA-15. Additionally, Pt particles are well dispersed in the channels of SBA-15, and Pt/CSBA-15 has a smaller Pt particle size than the catalyst without carbon modification (i.e., Pt/SBA-15). O2 is more feasibly adsorbed and activated on small-sized Pt particles, and in situ formed carbon species enhance the hydrophobicity of catalysts. As a result, both 3Pt/CSBA-15 and 5Pt/CSBA-15 are able to maintain 100% conversion of 50 ppm of C2H4 for more than 7 h at 0 °C. 3Pt/CSBA-15 even achieves 81.5% C2H4 conversion and 71.6% CO2 yield after 20 h, exhibiting much more prominent catalytic performances than 3Pt/SBA-15. DFT calculations and in situ FTIR measurements confirm that small-sized Pt particles possess strong O2 affinity to promote O2 adsorption, and in situ formed hydrophobic carbon layers efficiently suppress competitive H2O adsorption. Such a unique one-step catalyst preparation method for regulating the size of metal particles and the hydrophobicity of catalysts can be perfectly utilized to develop simple and efficient hydrophobic catalysts applied in low-temperature oxidation of C2H4.

Benzenepoly(carboxylic acid)s as Exclusive Intrinsic Markers to Assess Riverine Export of Dissolved Black Carbon

Landscape fires annually generate large quantities of black carbon. The water-soluble fraction of black carbon (i.e., dissolved black carbon/DBC) is an important constituent of the dissolved organic carbon (DOC) pool, playing a crucial role in the global budget of refractory carbon and climate change. A key challenge in constraining the flux and fate of riverine DBC is to develop targeted and accurate quantification methods. Herein, we report that benzenepentacarboxylic acid (B5CA) intrinsically present in DBC can be used as an exclusive and holistic marker (representing both condensed aromatics and less-/nonaromatic fractions) for DBC quantification. B5CA was universally detected in water extractions of biochar and fire-affected soils with relatively large abundance but not produced by nonthermogenic processes. It has good mobility in the environment as it is not readily precipitated by cations or adsorbed by common geosorbents. B5CA also represents the recalcitrant components of DBC with excellent stability against photodegradation and biodegradation. Applying B5CA as the DBC marker in surface waters of the Changjiang River (i.e., the third largest river in the world), we calculate the DBC concentration in the downstream Changjiang River to be 4.8 ± 5.5% of the DOC flux. Our work provides a simple and reliable approach for the accurate quantification and source tracking of DBC in the soil and aquatic carbon pools.

Dissolved black carbon mediated photo-oxidation of arsenic(III) to arsenic(V) in water: The key role of triplet states

Arsenic is a common contaminant found in natural waters, and has raised significant environmental concerns due to its toxicity and carcinogenicity. In this study, we investigated the mediated photo-oxidation of arsenite (As(III)) under simulated sunlight by dissolved black carbon (DBC), an important dissolved organic matter (DOM) constituent released from black carbon. Five DBC were collected from the water extracts of black carbons that were derived by pyrolyzing different biomass (i.e., bamboo, rice, peanuts, corn, and sorghum stalks), and four well-studied dissolved humic substances (DHS) were selected for benchmarking. The presence of DBC (i.e., 5 mg C-1) significantly accelerated the photo-oxidation of As(III) to arsenate (As(V)), with the observed pseudo-first-order rate constant of reaction increased by 5∼11 times. Quenching experiments of photochemically produced reactive intermediates suggested that As(III) was mainly oxidized by triplet-excited DBC (3DBC*, contribution of 48%), singlet oxygen (1O2, 18%) and superoxide anions (O2•-, 28%) in sunlight-irradiated DBC solutions. The average apparent quantum yield of As(III) photo-oxidation for DBC was found to be more than 4 times higher in comparison with DHS. Such a strong mediation efficiency of DBC was due to its smaller molecular size and higher aromaticity than DHS, which facilitated the non-charge-transfer process to produce triplet-excited states and their sensitized 1O2. Consistently, DBC exhibited a higher apparent quantum yield and a longer lifetime of triplet states as compared with DHS. The results imply that DBC may play a previously unrecognized important role in the fate of arsenic in aquatic environments.

A deep supervised transformer U-shaped full-resolution residual network for the segmentation of breast ultrasound image

PURPOSE

Breast ultrasound (BUS) is an important breast imaging tool. Automatic BUS image segmentation can measure the breast tumor size objectively and reduce doctors' workload. In this article, we proposed a deep supervised transformer U-shaped full-resolution residual network (DSTransUFRRN) to segment BUS images.

METHODS

In the proposed method, a full-resolution residual stream and a deep supervision mechanism were introduced into TransU-Net. The residual stream can keep full resolution features from different levels and enhance features fusion. Then, the deep supervision can suppress gradient dispersion. Moreover, the transformer module can suppress irrelevant features and improve feature extraction process. Two datasets (dataset A and B) were used for training and evaluation. The dataset A included 980 BUS image samples and the dataset B had 163 BUS image samples.

RESULTS

Cross-validation was conducted. For the dataset A, the proposed DSTransUFRRN achieved significantly higher Dice (91.04 ± 0.86%) than all compared methods (p < 0.05). For the dataset B, the Dice was lower than that for the dataset A due to the small number of samples, but the Dice of DSTransUFRRN (88.15% ± 2.11%) was significantly higher than that of other compared methods (p < 0.05).

CONCLUSIONS

In this study, we proposed DSTransUFRRN for BUS image segmentation. The proposed methods achieved significantly higher accuracy than the compared previous methods.

Effect of low molecular weight organic acids on the lead and chromium release from widely-used lead chromate pigments under sunlight irradiation

Lead chromate pigments are commonly used yellow inorganic pigments. They can pose environmental risks as they contain toxic heavy metals lead and chromium. Low molecular weight organic acids (LMWOAs), as widespread dissolved organic matter (DOM), affect the lead and chromium release from the pigment in water. In this work, the role of LMWOAs in the photodissolution of commercial lead chromate pigment was investigated. The pigment underwent significant photodissolution under simulated sunlight exposure with LMWOAs, and subsequently released Cr(III) and Pb(II). The photodissolution process is caused by the reduction of Cr(VI) by photogenerated electrons of the lead chromate pigment. The LMWOAs promoted photodissolution of the pigment by improving the electron-hole separation. The formation of Cr(III)-contained compounds leads to a slower release of chromium than lead. The photodissolution kinetics increase with decreasing pH and increasing LMWOAs concentration. The photodissolution of lead chromate pigment was basically positively related to the total number of hydroxyl and carboxyl groups in LMWOAs. The LMWOAs with stronger affinity to lead chromate pigment, lower adiabatic ionization potential (AIP) and higher energy of the highest occupied molecular orbital (EHOMO) are favorable to Cr(VI) reduction by photogenerated electrons and pigment photodissolution. 2.39% of chromium and 10.34% of lead released from the lead chromate pigment in natural conditions during a 6-h sunlight exposure. This study revealed the photodissolution mechanism of lead chromate pigment mediated by LMWOAs with different molecular structures, which helps understand the environmental photochemical behavior of the pigment. The present results emphasize the important role of DOM in the heavy metals release from commercial inorganic pigments.

Intrinsic peroxidase-like activity of dissolved black carbon released from biochar

Dissolved black carbon (DBC) is an important constituent of the natural organic carbon pool, influencing the global carbon cycling and the fate processes of many pollutants. In this work, we discovered that DBC released from biochar has intrinsic peroxidase-like activity. DBC samples were derived from four biomass stocks, including corn, peanut, rice, and sorghum straws. All DBC samples catalyze H2O2 decomposition into hydroxyl radicals, as determined by the electron paramagnetic resonance and the molecular probe. Similar to enzymes that exhibit saturation kinetics, the steady-state reaction rates follow the Michaelis-Menten equation. The peroxidase-like activity of DBC is controlled by the ping-pong mechanism, as suggested by parallel Lineweaver-Burk plots. Its activity increases with temperature from 10 to 80 °C and has an optimum at pH 5. The peroxidase-like activity of DBC is positively correlated with its aromaticity as aromatics can stabilize the reactive intermediates. The active sites in DBC also involve oxygen-containing groups, as inferred by increased activity after the chemical reduction of carbonyls. The peroxidase-like activity of DBC has significant implications for biogeochemical processing of carbon and potential health and ecological impacts of black carbon. It also highlights the need to advance the understanding of the occurrence and role of organic catalysts in natural systems.

Black carbon, soil organic matter molecular signatures under different land uses in Shenyang, China and relationship with PAHs

The content, composition and molecular signatures of soil organic matter (SOM) have important influences on the cycle of soil organic carbon (SOC) and the partitioning of polycyclic aromatic hydrocarbons (PAHs) in soil. Seventy-nine soil samples from farmland, forest and urban areas were collected in Shenyang, China to investigate black carbon (BC) content, SOM molecular signatures varied with land use patterns, as well as the relationship with PAHs. The content of BC in urban soils was significantly higher than that of farmland and forest. BC was a key contributor of urban SOM which accounted for 0.35 ± 0.31 of SOC in urban soil. Based on BC/SOC ratio, the main sources of BC were identified as fossil fuel combustion for urban soils, while for farmland and forest soils, it is the mixed results of fossil fuel combustion and biomass burning. All categories of PAHs in urban soils showed the highest level compared to farmland and forest soils. Pearson's correlation analysis results showed there were significant positive correlations between BC and PAHs categories in urban soils, indicating the important role of BC in the accumulation of PAHs in soil. SOM from each of the two different land use patterns can be distinguished by molecular signatures. Urban SOM had abundant molecular markers derived from condensed organic carbon inputs, which was consistent with the BC/SOC value. Farmland SOM had abundant carbon from vegetation and microorganisms, and forest SOM was rich in organic carbon from fresh plant materials. The markers enriched in urban SOM showed significant correlations with most PAHs categories, highlighting the affinity of urban SOM for PAHs at the molecular level. This study contributed to understanding the impact of land management methods on SOM molecular composition signatures and its influence on PAHs occurrence in soil, providing a theoretical basis for regional soil pollution management.

Ni12P5 Confined in Mesoporous SiO2 with Near-Unity CO Selectivity and Enhanced Catalytic Activity for CO2 Hydrogenation

CO2 hydrogenation via the reverse water gas shift (RWGS) reaction is a promising strategy for CO2 utilization while constructing Ni-based catalysts with high catalytic activity and perfect CO selectivity remains a great challenging. Here, we demonstrate that the product selectivity for CO2 hydrogenation can be significantly tuned from CH4 to CO by phosphating of SiO2-supported Ni catalysts due to the geometric effect. Interestingly, nickel phosphide catalysts with different crystalline phases (Ni12P5 and Ni2P) differ sharply in CO2 conversion, and Ni12P5 is remarkably more active. Furthermore, we developed a facile strategy to confine small Ni12P5 nanoparticles in mesoporous SiO2 channels (Ni12P5@SBA-15). Enhanced activity is exhibited on Ni12P5@SBA-15, ascribed to the highly effective confinement effect. The in situ diffuse reflectance infrared Fourier transform spectroscopy and density functional theory calculations unveil that catalytic CO2 hydrogenation follows a direct CO2 dissociation route with adsorbed CO as the key intermediate. Notably, strong multibonded CO (threefold and bridge-bonded CO) is feasibly formed on the Ni catalyst accounting for CH4 as the dominant product whereas only weak linearly bonded CO exists on nickel phosphide catalysts resulting in almost 100% CO selectivity. The present results indicate that Ni12P5@SBA-15 combining the geometric effect and the confinement effect can achieve near-unity CO selectivity and enhanced activity for CO2 hydrogenation.

Complex Transformer Network for Single-Angle Plane-Wave Imaging

OBJECTIVE

Plane-wave imaging (PWI) is a high-frame-rate imaging technique that sacrifices image quality. Deep learning can potentially enhance plane-wave image quality, but processing complex in-phase and quadrature (IQ) data and suppressing incoherent signals pose challenges. To address these challenges, we present a complex transformer network (CTN) that integrates complex convolution and complex self-attention (CSA) modules.

METHODS

The CTN operates in a four-step process: delaying complex IQ data from a 0° single-angle plane wave for each pixel as CTN input data; extracting reconstruction features with a complex convolution layer; suppressing irrelevant features derived from incoherent signals with two CSA modules; and forming output images with another complex convolution layer. The training labels are generated by minimum variance (MV).

RESULTS

Simulation, phantom and in vivo experiments revealed that CTN produced comparable- or even higher-quality images than MV, but with much shorter computation time. Evaluation metrics included contrast ratio, contrast-to-noise ratio, generalized contrast-to-noise ratio and lateral and axial full width at half-maximum and were -11.59 dB, 1.16, 0.68, 278 μm and 329 μm for simulation, respectively, and 9.87 dB, 0.96, 0.62, 357 μm and 305 μm for the phantom experiment, respectively. In vivo experiments further indicated that CTN could significantly improve details that were previously vague or even invisible in DAS and MV images. And after being accelerated by GPU, the CTN runtime (76.03 ms) was comparable to that of delay-and-sum (DAS, 61.24 ms).

CONCLUSION

The proposed CTN significantly improved the image contrast, resolution and some unclear details by the MV beamformer, making it an efficient tool for high-frame-rate imaging.

A joint method of coherence factor and nonlinear beamforming for synthetic aperture imaging with a ring array

Ultrasound computed tomography (USCT) with a ring array is an emerging diagnostic method for breast cancer. In the literature, synthetic aperture (SA) imaging has employed the delay-and-sum (DAS) beamforming technique for ring-array USCT to obtain isotropic resolution reflection images. However, the images obtained by the conventional DAS beamformer suffer from off-axis clutter and low resolution due to inhomogeneity of the medium and phase distortion. To address these issues, researchers have developed adaptive beamforming methods, such as coherence factor (CF) and convolutional beamforming algorithm (COBA), that improve image quality. In this study, we propose a joint method that combines CF with short-lag COBA (SLCOBA). First, we estimate the average sound speed using CF to address tissue inhomogeneity. Based on the corrected sound speed map, SLCOBA effectively suppresses side lobes and enhances image quality. Numerical results show that the proposed method reduces clutter and noise, improving resolution performance. These findings suggest that the proposed method may be a practical option for breast imaging in inhomogeneous mediums in the future.

ZnO Nanorod-Immobilized Pt Single-Atoms as an Ultrasensitive Sensor for Triethylamine Detection

Triethylamine (TEA) is a flammable and highly toxic gas, and the fast, accurate, and sensitive detection of gas TEA remains greatly challenging. Herein, we report a ZnO nanorod anchored with a single-atom Pt catalyst (Pt₁/ZnO) as a gas sensor for TEA detection. The sensor shows high selectivity and high response to gas TEA with a response value of 4170 at 200 °C, which is 92 times higher than that of pure ZnO. Moreover, the Pt₁/ZnO sensor has very short response and recovery times of only 34 and 76 s, respectively, and also has a high response to ppb-level TEA gas (100 ppb-21.6). The gas-sensing enhancement mechanism of the Pt₁/ZnO sensor to gas TEA was systematically investigated using band structure analysis, in situ diffuse reflectance infrared Fourier transformation spectroscopy, and density functional theory calculations. The results show that the oxygen vacancies on Pt₁/ZnO can effectively activate the adsorbed oxygen. Moreover, chemical bonds can be formed between Pt single atoms and N atoms in TEA to achieve effective adsorption and activation of TEA molecules, facilitating the reaction between TEA and the adsorbed oxygen on Pt₁/ZnO, and thereby obtaining high gas-sensing performance. This work highlights the crucial role of Pt single-atom in improving the sensing performance for gas TEA detection, paving the way for developing more advanced gas sensors.

Impacts of dissolved organic matter on the aggregation and photo-dissolution of cadmium pigment nanoparticles in aquatic systems

Cadmium pigments are a group of inorganic pigments used in consumer products. The aggregation behavior and photo-dissolution process of cadmium pigment nanoparticles in aquatic systems control their environmental fate, which is largely unknown. Herein, we investigated the influence of dissolved organic matter (DOM) on the aggregation behavior and photo-dissolution process of CdS nanoparticles in aquatic systems. Bare CdS nanoparticles are prone to aggregation in both NaCl and CaCl₂ solutions. DOM can remarkably increase the colloidal stability of CdS nanoparticles owing to the steric hindrance and enhanced electrostatic repulsion. With 10 mg/L Suwannee River natural organic matter (SRNOM), the colloidal stability of CdS nanoparticles is significantly enhanced in NaCl solutions (i.e., the critical coagulation concentration, CCC_Na, is 707.2 mM). Suwannee River humic acid (SRHA) has a stronger stabilization effect than SRNOM due to its higher molecular weight and aromaticity. The Ca²⁺ cations can induce charge neutralization and structural compacting of DOM corona, efficiently reducing the colloidal stability of CdS nanoparticles. The CCC_Ca is 10.8 mM and 14.9 mM with 10 mg/L SRNOM and SRHA, respectively. Upon solar irradiation, the presence of a low concentration of SRNOM (3 mg/L) can enhance the photo-dissolution of CdS nanoparticles and the consequent Cd²⁺ leaching. This is caused by the facilitated electron transfer from CdS nanoparticles to O₂ induced by SRNOM corona, leading to better electron-hole separation. However, a high concentration of SRNOM inhibited the photo-dissolution of CdS nanoparticles due to the strong inner filter effect and the scavenging of phototransients. The colloidal stability of SRNOM-coated CdS nanoparticles increases in NaCl but decreases in CaCl₂ solutions after irradiation owing to the oxidation of SRNOM corona. Our results highlight the decisive role of DOM in the environmental fate of cadmium pigments.

A nanozyme-like colorimetric sensing strategy based on persulfate activation on Co-based metal-organic frameworks

A nanozyme-like colorimetric sensing strategy based on persulfate activation on Co-based metal-organic frameworks is developed for biomolecule detection in solution and on paper strips. By switching from H₂O₂ activation on nanozymes to catalytic persulfate activation, this general strategy provides higher sensitivity, faster speed, and wider application ranges for detection.

[Proposal and thoughts on establishing and improving multi-level dental insurance in China]

Oral diseases are highly prevalent in China, while oral health services are generally underutilized and public health resources are wasted. Lacking oral insurance may be one of the leading causes. The basic medical insurance of China does not cover dental care in most cities, which is worthy to further discuss. To better understand the experience of dental insurance from international dental care practice, the dental coverage scope, content, co-pay ratio, and effects of oral insurance on oral health improvement from the abroad countries with typical health insurance systems were summarized by using scoping review. Then, we discussed the coverage scope for dental health of basic medical insurance and private insurance in China. We also analyzed the current issues of dental care coverage and cost-share. At last, we proposed thoughts and suggestions to establish and improve a multi-level oral health insurance system with Chinese characteristics under the basic medical insurance frame. In particular, we gave suggestions on increasing the coverage for high dental care xpenditure by ebasic medical insurance, supplying children and teenagers with preventive dental care, and encouraging private insurance companies to cover dental care expenditure.

Acrylamide-induced meiotic arrest of spermatocytes in adolescent mice by triggering excessive DNA strand breaks: Potential therapeutic effects of resveratrol

Background: Baked carbohydrate-rich foods are the main source of acrylamide (AA) in the general population and are widely consumed by teenagers. Considering the crucial development of the reproductive system during puberty, the health risks posed by AA in adolescent males have raised public concern.Methods: In this study, we exposed 3-week-old male pubertal mice to AA for 4 weeks to evaluate its effect on spermatogenesis using computer-assisted sperm analysis (CASA) and historical analysis. Flow cytometric analysis and meiocyte spreading assay were conducted to assess meiosis in mice. The expression of meiosis-related proteins and double-strand break (DSB) proteins were evaluated by immunoblot analyses. Additionally, isolated spermatocytes were used to explore the role of resveratrol in AA-induced damages of meiosis.Results: Our results showed that AA decreased the testicular and epididymal indexes, reduced sperm count and motility, and induced morphological disruption of the testes in pubertal mice. Subsequent meiotic analysis revealed that AA increased the proportion of 4C spermatocytes and decreased the proportion of 1C spermatids. The expression levels of meiosis-related proteins (SYCP3, Cyclin A1 and CDK2) were downregulated, and signaling proteins (γH2AX, p-CHK2 and p-ATM) expression levels were upregulated in AA-treated mice testes. Similar expression patterns were observed in primary spermatocytes treated with AA and these effects were reversed significantly by resveratrol.Conclusions: Our results indicate that AA induces meiotic arrest via persistent activation of DSBs, which may contribute to AA-compromised spermatogenesis. Resveratrol could serve as a potential therapeutic agent against AA-induced meiotic toxicity. These data highlight the importance of natural product supplementation for treating AA-related reproductive toxicity.

Effective catalytic hydrodechlorination removal of chloroanisole odorants in water using palladium catalyst confined in zeolite Y

Chloroanisoles is a class of odorous pollutants commonly identified in drinking water. In the present study, we confined noble metal palladium (Pd) in the micropores of zeolite Y (ie-Pd@Y) using an ion exchange method, and applied it for the catalytic hydrodechlorination removal of chloroanisoles (represented by 2,4,6-trichloroanisole/TCA) in water. Pd supported on zeolite Y surface (im-Pd/Y, prepared by conventional impregnation method) was used as the benchmarking catalyst. The characterization results revealed that ie-Pd@Y had smaller Pd particle size and higher Pdⁿ⁺/Pd⁰ ratio than im-Pd/Y. The catalytic hydrodechlorination of TCA followed a concerted dechlorination pathway and the Langmuir-Hinshelwood model. The ie-Pd@Y catalysts with different Pd loadings exhibit excellent catalytic activities with more than 95% of TCA removed within 30 min, which is far superior to the im-Pd/Y catalysts (27-70%). Moreover, due to the confinement effect of zeolite Y, ie-Pd@Y displayed enhanced catalytic stability as compared with im-Pd/Y. The initial activity of ie-Pd@Y was more than 20 times higher than that of im-Pd/Y after five reaction cycles. Additionally, with the assistance of sieving effect, ie-Pd@Y displayed much stronger capability against the interference from dissolved organic matter than im-Pd/Y. The present results demonstrate that the confined catalysts ie-Pd@Y can be applied in liquid phase catalytic hydrogenation to effectively eliminate halogenated odorants in waters.

Resectability of bilobar liver tumours after simultaneous portal and hepatic vein embolization versus portal vein embolization alone: meta-analysis

BACKGROUND

Many patients with bi-lobar liver tumours are not eligible for liver resection due to an insufficient future liver remnant (FLR). To reduce the risk of posthepatectomy liver failure and the primary cause of death, regenerative procedures intent to increase the FLR before surgery. The aim of this systematic review is to provide an overview of the available literature and outcomes on the effectiveness of simultaneous portal and hepatic vein embolization (PVE/HVE) versus portal vein embolization (PVE) alone.

METHODS

A systematic literature search was conducted in PubMed, Web of Science, and Embase up to September 2022. The primary outcome was resectability and the secondary outcome was the FLR volume increase.

RESULTS

Eight studies comparing PVE/HVE with PVE and six retrospective PVE/HVE case series were included. Pooled resectability within the comparative studies was 75 per cent in the PVE group (n = 252) versus 87 per cent in the PVE/HVE group (n = 166, OR 1.92 (95% c.i., 1.13-3.25)) favouring PVE/HVE (P = 0.015). After PVE, FLR hypertrophy between 12 per cent and 48 per cent (after a median of 21-30 days) was observed, whereas growth between 36 per cent and 67 per cent was reported after PVE/HVE (after a median of 17-31 days). In the comparative studies, 90-day primary cause of death was similar between groups (2.5 per cent after PVE versus 2.2 per cent after PVE/HVE), but a higher 90-day primary cause of death was reported in single-arm PVE/HVE cohort studies (6.9 per cent, 12 of 175 patients).

CONCLUSION

Based on moderate/weak evidence, PVE/HVE seems to increase resectability of bi-lobar liver tumours with a comparable safety profile. Additionally, PVE/HVE resulted in faster and more pronounced hypertrophy compared with PVE alone.

Assessing organic fouling of ultrafiltration membranes using partition coefficients of dissolved organic matter in aqueous two-phase systems

Organic fouling caused by dissolved organic matter (DOM) is a critical challenge for membrane technologies. In this study, prediction models for the fouling of commercial polyether sulfone (PES) and regenerated cellulose (RC) ultrafiltration membranes by DOM were established based on the hydrophobicity of DOM. The organic fouling behavior of 40 natural water samples collected from Lake Taihu was investigated. The fouling propensity of water samples on ultrafiltration membranes was evaluated using the fouling index (FI). The hydrophobicity of DOM in water samples was quantified by its partition coefficient in an aqueous two-phase system (K_ATPS). The FI of water samples on RC membranes was lower than that on PES membranes due to stronger repulsive Lewis acid-base interactions, which reduced DOM-membrane interactions. A significant positive correlation was found between K_ATPS and FI, suggesting the important role of DOM hydrophobicity in the organic fouling of ultrafiltration membranes. FI prediction models using K_ATPS as the variable were established using a training group containing 20 water samples for PES and RC membranes, respectively. The resulting models were then validated using the additional 20 water samples, which suggested good prediction power (RMSE = 1.65). The pH effect on the organic fouling can be adequately predicted by the same model with K_ATPS values measured at given pH. The results suggest that K_ATPS can be used as a convenient index for assessing the initial organic fouling of ultrafiltration membranes by freshwater DOM.

Efficient and reductive removal of bromate using a novel and stable nanoscale zero-valent iron embedded in N-doped carbon derived from metal-organic frameworks

Nanoscale zero-valent iron (nZVI) has drawn great interest in the remediation of contaminated waters. In this study, we prepared a novel and stable nZVI embedded in N-doped carbon matrix (nZVI@MOF-CN) using a facile direct carbonization method, in which an iron-containing metal-organic framework (MOF) served as both the iron and carbon sources, and melamine as the nitrogen source. The nZVI@MOF-CN composites were used in the removal of bromate in water, which could be effectively reduced by the surface electrons transferred from nZVI to the carbon encapsulation layer due to the Schottky-Mott effect. Doped nitrogen significantly facilitated the reduction of bromate by nZVI, because it enhanced the nZVI dispersion and bromate adsorption, and modulated the carbon matrix conductivity. The bromate reduction activity of nZVI@MOF-CN was more than 50 times higher that of its un-doped counterpart and a commercial nZVI. Moreover, owing to the protection of carbon encapsulation layer, nZVI@MOF-CN exhibited good stability and reusability. The leached concentration of iron ions of nZVI@MOF-CN was less than 5% of the commercial nZVI under the same reaction conditions. Commercial nZVI almost completely lost its bromate reduction activity after use (3% reduction efficiency in the examined time frame), while nZVI@MOF-CN maintained a reduction efficiency of 61%. The nZVI@MOF-CN could be effectively regenerated by hydrogenation reduction. After five reaction-regeneration cycles, nZVI@MOF-CN still achieved a bromate reduction efficiency of approximately 80%. These results suggest that MOF-derived nZVI materials are highly reactive and stable for the reductive removal of pollutants in water.

Highly effective electrocatalytic reduction of N-nitrosodimethylamine on Ru/CNT catalyst

N-Nitrosodimethylamine (NDMA) is a commonly identified carcinogenic and genotoxic pollutant in water. In this study, we prepared Ru catalysts supported on carbon nanotube (Ru/CNT) and studied the electrocatalytic reduction of N-nitrosamines on Ru/CNT electrode in a three-electrode system. The results show that Ru-based catalyst exhibits a high activity of 793.3 μmol L^-1 gCat^-1 h^-1 for electrochemical reduction of NDMA. Reaction mechanism study discloses that the electrocatalytic reduction of NDMA is accomplished by both direct electron reduction and atomic H* mediated indirect reduction pathways. Further product analysis indicates that NDMA is finally reduced to dimethylamine (DMA) and ammonia. The reduction efficiency of NDMA strongly relies on cathode potential, initial NDMA concentration and solution pH. To verify the universality of Ru/CNT electrode, electrocatalytic reduction of three dialkyl N-nitrosamines with different alkyl groups was performed and Ru catalyst has high catalytic activities for the three N-nitrosamines, while the catalytic efficiency differs with their structures. Simultaneous electrochemical reduction of the three N-nitrosamines indicates that the reduction rates of N-nitrosamines follow the same order in the multiple-component system as that in the single-component system. Catalyst recycling results demonstrate that after 5 consecutive recycling runs Ru/CNT electrode remains almost identical catalytic activity to the fresh catalyst, manifesting the high catalytic stability of Ru/CNT electrode.

Deep-Learning-Based Ultrasound Sound-Speed Tomography Reconstruction with Tikhonov Pseudo-Inverse Priori

Ultrasound sound-speed tomography (USST) is a promising technology for breast imaging and breast cancer detection. Its reconstruction is a complex non-linear mapping from the projection data to the sound-speed image (SSI). The traditional reconstruction methods include mainly the ray-based methods and the waveform-based methods. The ray-based methods with linear approximation have low computational cost but low reconstruction quality; the full wave-based methods with the complex non-linear model have high quality but high cost. To achieve both high quality and low cost, we introduced traditional linear approximation as prior knowledge into a deep neural network and treated the complex non-linear mapping of USST reconstruction as a combination of linear mapping and non-linear mapping. In the proposed method, the linear mapping was seamlessly implemented with a fully connected layer and initialized using the Tikhonov pseudo-inverse matrix. The non-linear mapping was implemented using a U-shape Net (U-Net). Furthermore, we proposed the Tikhonov U-shape net (TU-Net), in which the linear mapping was done before the non-linear mapping, and the U-shape Tikhonov net (UT-Net), in which the non-linear mapping was done before the linear mapping. Moreover, we conducted simulations and experiments for evaluation. In the numerical simulation, the root-mean-squared error was 6.49 and 4.29 m/s for the UT-Net and TU-Net, the peak signal-to-noise ratio was 49.01 and 52.90 dB, the structural similarity was 0.9436 and 0.9761 and the reconstruction time was 10.8 and 11.3 ms, respectively. In this study, the SSIs obtained with the proposed methods exhibited high sound-speed accuracy. Both the UT-Net and the TU-Net achieved high quality and low computational cost.

Synergistic effects boost electrocatalytic reduction of bromate on supported bimetallic Ru-Cu catalyst

Bromate is a commonly identified carcinogenic and genotoxic disinfection byproduct in water. In the present work, bimetallic Ru-Cu catalyst supported on carbon nanotube (RuCu/CNT) was prepared and the structural properties of the catalysts were characterized. The results show that the presence of Ru enhances the dispersion and reduction of Cu particles in the RuCu/CNT catalyst in comparison with the monometallic Cu catalyst supported on CNT (Cu/CNT). For electrocatalytic reaction on Cu/CNT, bromate is reduced on metallic Cu surface via a redox process. For Ru/CNT, highly active H* radicals are generated on metallic Ru surface via the Volmer process and are used for bromate reduction. As for the RuCu/CNT, bromate is reduced through two main pathways, including direct redox reaction on metallic Cu and indirect reduction by active H* radicals on Ru surface. Accordingly, RuCu/CNT exhibits the highest catalytic activity, ascribed to the synergistic effect between metallic Ru and Cu. Furthermore, the bimetallic catalyst displays much higher catalytic efficiency as compared with previously reported results. The pH, initial bromate concentration, in-situ electrochemical reduction of the electrodes and working potential have strong impacts on the removal efficiency of bromate on RuCu/CNT.

Dragon 1 Protocol Manuscript: Training, Accreditation, Implementation and Safety Evaluation of Portal and Hepatic Vein Embolization (PVE/HVE) to Accelerate Future Liver Remnant (FLR) Hypertrophy

STUDY PURPOSE

The DRAGON 1 trial aims to assess training, implementation, safety and feasibility of combined portal- and hepatic-vein embolization (PVE/HVE) to accelerate future liver remnant (FLR) hypertrophy in patients with borderline resectable colorectal cancer liver metastases.

METHODS

The DRAGON 1 trial is a worldwide multicenter prospective single arm trial. The primary endpoint is a composite of the safety of PVE/HVE, 90-day mortality, and one year accrual monitoring of each participating center. Secondary endpoints include: feasibility of resection, the used PVE and HVE techniques, FLR-hypertrophy, liver function (subset of centers), overall survival, and disease-free survival. All complications after the PVE/HVE procedure are documented. Liver volumes will be measured at week 1 and if applicable at week 3 and 6 after PVE/HVE and follow-up visits will be held at 1, 3, 6, and 12 months after the resection.

RESULTS

Not applicable.

CONCLUSION

DRAGON 1 is a prospective trial to assess the safety and feasibility of PVE/HVE. Participating study centers will be trained, and procedures standardized using Work Instructions (WI) to prepare for the DRAGON 2 randomized controlled trial. Outcomes should reveal the accrual potential of centers, safety profile of combined PVE/HVE and the effect of FLR-hypertrophy induction by PVE/HVE in patients with CRLM and a small FLR.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT04272931 (February 17, 2020). Toestingonline.nl: NL71535.068.19 (September 20, 2019).

Efficient inhibition of cyanobacteria M. aeruginosa growth using commercial food-grade fumaric acid

The control of cyanobacteria blooms is a global challenge. Here, we reported the efficient inhibition of M. aeruginosa by fumaric acid (FA), an intermediate metabolite of the tricarboxylic acid cycle. FA showed strong algicidal activity with an inhibition rate of 90.5% on the 8th day at a dose of 40 mg/L. The presence of FA caused severe membrane damage, as suggested by the fluorescence flow cytometry and morphology analysis. FA inhibited the formation of chlorophyll a, interrupting the photosynthesis system. It also induced oxidative stress in cells. Principal component analysis of the indicators suggested that the FA-treated sample had a significantly different inhibitory pattern than the acid-treated sample. Thus, the inhibitory effect was not solely caused by the pH effect. Untargeted metabolomic analysis revealed that 31 metabolites were differentially expressed in response to FA stress, which were mainly involved in the metabolite processes and the membranes. A commercial food-grade FA was able to inhibit the growth of M. aeruginosa similar to the analytical-grade FA. Our results suggest that FA can be potentially an efficient and low-risk chemical for inhibiting M. aeruginosa growth, which may find future applications in cyanobacteria bloom control.

Mechanism for selective binding of aromatic compounds on oxygen-rich graphene nanosheets based on molecule size/polarity matching

Selective binding of organic compounds is the cornerstone of many important industrial and pharmaceutical applications. Here, we achieved highly selective binding of aromatic compounds in aqueous solution and gas phase by oxygen-enriched graphene oxide (GO) nanosheets via a previously unknown mechanism based on size matching and polarity matching. Oxygen-containing functional groups (predominately epoxies and hydroxyls) on the nongraphitized aliphatic carbons of the basal plane of GO formed highly polar regions that encompass graphitic regions slightly larger than the benzene ring. This facilitated size match-based interactions between small apolar compounds and the isolated aromatic region of GO, resulting in high binding selectivity relative to larger apolar compounds. The interactions between the functional group(s) of polar aromatics and the epoxy/hydroxyl groups around the isolated aromatic region of GO enhanced binding selectivity relative to similar-sized apolar aromatics. These findings provide opportunities for precision separations and molecular recognition enabled by size/polarity match-based selectivity.

A VGG attention vision transformer network for benign and malignant classification of breast ultrasound images

PURPOSE

Breast cancer is the most commonly occurring cancer worldwide. The ultrasound reflectivity imaging technique can be used to obtain breast ultrasound (BUS) images, which can be used to classify benign and malignant tumors. However, the classification is subjective and dependent on the experience and skill of operators and doctors. The automatic classification method can assist doctors and improve the objectivity, but current convolution neural network (CNN) is not good at learning global features and vision transform (ViT) is not good at extraction local features. In this study, we proposed an VGG attention vision transformer (VGGA-ViT) network to overcome their disadvantages.

METHODS

In the proposed method, we used a convolutional neural network (CNN) module to extract the local features and employed a vision transformer (ViT) module to learn the global relationship between different regions and enhance the relevant local features. The CNN module was named the VGG attention (VGGA) module. It was composed of a visual geometry group (VGG) backbone, a feature extraction fully connected layer, and a squeeze-and-excitation (SE) block. Both the VGG backbone and the ViT module were pre-trained on the ImageNet dataset and re-trained using BUS samples in this study. Two BUS datasets were employed for validation.

RESULTS

Cross-validation was conducted on two BUS datasets.

CONCLUSIONS

In this study, we proposed the VGGA-ViT for the BUS classification, which was good at learning both local and global features. The proposed network achieved higher accuracy than the compared previous methods. This article is protected by copyright. All rights reserved.

An improved method to predict polycyclic aromatic hydrocarbons in surface freshwater by reducing the input parameters

Predicting the concentration of polycyclic aromatic hydrocarbons (PAHs) in surface freshwater are critical for understanding their spatio-temporal distribution, regulation effectiveness, and the subsequent health risks. In this study, by exploring the correlation of PAHs concentrations in surface freshwater (C_PAHs) in China reported in the past twenty years with their emission (E_PAHs), a novel relationship of C_PAHs with E_PAHs and PAHs properties (i.e., logK_ow and S_w) was established. For PAHs individual, percent sample deviation between the measured concentrations and the calculated concentrations are in the range of 18% to 48%, suggesting that the calculated concentrations of PAHs are well consistent with the measured PAHs concentration in surface freshwater. Moreover, spatial distribution of predicted PAHs concentrations in surface freshwater of China is also matched well with measured ones. Compared with other environmental models, the established relationships in this work can reduce the number of model parameters from dozens to three, as well as decrease percent sample deviation from several orders of magnitude to less than 50%. The established relationship of PAHs concentrations in surface freshwater with E_PAHs, S_w, and logK_ow of PAHs, are valuable to facilitate the prediction of PAHs concentrations in surface freshwater by reducing monitoring costs.

[Prevalence and frequencies of human papilloma virus types in adenocarcinoma in situ of the uterine cervix]

Objective: To examine the prevalence and frequencies of human papillomavirus (HPV) genotypes in cervical adenocarcinoma in situ (AIS). Methods: The cases of cervical AIS with concurrent tests of cytology and HPV typing from January 2007 to February 2020 in the Obstetrics and Gynecology Hospital of Fudan University were collected and analyzed. Results: A total of 478 cases of cervical AIS were obtained. The average age of the patients was 39.4 years (range, 19-81 years). The largest age group was 30-39 years (44.8%), followed by 40-49 years (34.7%). Among the 478 patients, 355 underwent high-risk HPV (hrHPV) testing and had a hrHPV-positive rate of 93.8%. Of the 355 patients, 277 also underwent HPV typing and were mostly positive for either or both HPV16 and HPV18 (93.1%), with 55.6% positive for HPV18 and 48.7% positive for HPV16. Among the 478 cases, 266 cases (55.6%) were diagnosed with both AIS and squamous intraepithelial lesion (SIL), while 212 cases (44.4%) were diagnosed with only AIS. Patients infected with HPV16 in the AIS and SIL group significantly outnumbered those in the AIS alone group (P<0.05). Moreover, the rate of positive cytology was 55.9% (167/299 cases), while that of negative cytology was 44.1% (132/299). Among the 109 patients with negative cytology results and co-tested hrHPV, there were 101 HPV-positive cases (92.7%), of which 88 cases were subject to HPV typing and showed an HPV16/18 positive rate of 94.3% (83/88 cases). Conclusions: The combination of HPV typing and cytological screening can maximize the detection rate of cervical AIS, and should continue to be utilized, ideally on a larger scale, in the future.

Current and Future Trends of Low and High Molecular Weight Polycyclic Aromatic Hydrocarbons in Surface Water and Sediments of China: Insights from Their Long-Term Relationships between Concentrations and Emissions

In this study, we analyzed the temporal trend of polycyclic aromatic hydrocarbons (PAHs) in China using data reported over the past 20 years. We found that the total concentrations of low molecular weight PAHs (C_ΣLPAHs) in surface water and sediments were positively correlated with their total emissions (E_ΣLPAHs), which increased between 2000 and 2008, then decreased until 2017. Additionally, the total concentrations of high molecular weight PAHs (C_∑HPAHs) in surface water and sediments were positively correlated with their total emissions (E_ΣHPAHs), which increased significantly from 2000 to 2014 and then plateaued. Two future scenarios were assessed to explore C_∑LPAHs and C_∑HPAHs in surface water and sediments. PAH emissions were reduced by technological improvement in 2030 for coal consumption in Scenario 1 and for control of biomass burning in Scenario 2. Scenario 1 was more efficient than Scenario 2 in reducing C_∑HPAHs in the surface water and sediments of China for the areas where C_ΣHPAHs in surface water exceeded the annual average standard (i.e., 30 ng L^-1), with reductions of 38 and 24% in Scenarios 1 and 2, respectively. The observed relationships in this study can provide tools for emission reduction policies in the future.

Localized motion imaging for monitoring HIFU therapy: Comparison of modulating frequencies and utilization of square modulating wave

High-intensity focused ultrasound (HIFU) has been successfully used as a minimally invasive cancer therapy method. For monitoring the therapy, the amplitude-modulated (AM) localized motion imaging (LMI) method had been proposed. This paper compares the performance of AM-LMI while using different sine modulating wave frequencies and proposes the utilization of square modulating waves to gain the advantages of both high and low modulating frequencies. A single element therapy transducer with a 2 MHz central frequency was driven by sine modulating waves with different frequencies (approximate 34, 67, 102, 168, and 201 Hz) and by square modulating waves with two frequencies (34 and 67 Hz). An imaging probe with a 5 MHz central frequency and a 20 MHz sampling frequency was mounted in the center hole of the therapy transducer to acquire pulse-echo data, which were used to estimate the tissue oscillation amplitude induced by the acoustic radiation force of the HIFU beam. The decrease ratio of the oscillation amount was then utilized to estimate the coagulated lesion length during the therapy. The comparison of modulating frequencies demonstrated that a higher frequency could bring higher sensitivity to small lesions, while a lower frequency not only gives greater noise robustness but also promotes the ability to estimate lengths of larger lesions. The utilization of a square modulating wave demonstrated its utility to produce tissue oscillation with multiple frequencies and gain the advantages of both high and low modulating frequencies.

Predicting the total PAHs concentrations in sediments from selected congeners using a multiple linear relationship

In this study, we observed that four congeners, including naphthalene (Nap), acenaphthylene (Acy), phenanthrene (Phe), and benz(a)anthracene (BaA), are the characteristic congeners for predicting the emission and the sediment concentrations of polycyclic aromatic hydrocarbons (PAHs). A novel multiple relationship of the total PAHs concentrations (C_∑PAHs) in sediments with the concentrations of four congeners was established (p < 0.01, R² = 0.95) using published data over the past 30 years. Moreover, the multiple linear relationship of the total PAHs emission factors with the emission factors of four congeners was also established (p < 0.01, R² = 0.99). Interestingly, the ratio of multicomponents coefficient from the multiple linear relationship in sediments to that from the multiple linear relationship in emission sources correlated positively with octanol–water partition coefficient (logK_ow) (p < 0.01, R² = 0.88) of the four PAHs congeners. Therefore, a novel model was established to predict C_ΣPAHs in sediments using the emissions and logK_ow of the four characteristic PAHs congeners. The percent sample deviation between calculated C_∑PAHs and their observed values was 54%, suggesting the established model can accurately predict C_ΣPAHs in sediments.

Comparing Photoactivities of Dissolved Organic Matter Released from Rice Straw-Pyrolyzed Biochar and Composted Rice Straw

Here, we systematically compared the photoactivity and photobleaching behavior between dissolved black carbon (DBC) from rice straw biochar and leached dissolved organic carbon (LDOC) from rice straw compost using complementary techniques. The Fourier transform-ion cyclotron resonance mass spectrometry (FT-ICR MS) analysis showed that DBC was dominated by polycyclic aromatic (55.1%) and tannin-like molecules (24.1%), while LDOC was dominated by lignin-like (58.9%) and tannin-like molecules (19.7%). Under simulated sunlight conditions, DBC had much higher apparent quantum yields for ³DOM* and ¹O₂ but much lower apparent quantum yields for ^•OH than LDOC. After a 168 h irradiation, the total number of LDOC formulas identified by FT-ICR MS decreased by 40.1% with concurrent increases in O/C and H/C ratios and also decreases in double bond equivalence minus oxygen (DBE - O) and average molecular weight identified by gel permeation chromatography. However, despite the large decreases in UVA₂₅₄ and DOC, the total number of DBC formulas decreased only by 12.0% with nearly unchanged O/C ratio, DBE - O values, molecular weight distribution, and benzenepolycarboxylic aromatic condensation (BACon) index regardless of the decreased percentage of condensed aromatic carbon (ConAC %). Compared with LDOC, the photolysis of DBC was much less oxidative and destructive mainly via breakup of a small portion of the highly condensed aromatic rings, probably accompanied by photodecarboxylation.

Rapid detoxification of Microcystin-LR by selective catalytic hydrogenation of the Adda moiety using TiO2-supported Pd catalysts

The hepatotoxicity of Microcystin-LR (MC-LR) is mainly caused by its Adda moiety. In this study, we used TiO₂-supported Pd catalysts to selectively hydrogenate the CC bonds in the Adda moiety, achieving rapid detoxification of MC-LR in water under ambient conditions. MC-LR was removed within 5 min by catalytic hydrogenation on Pd(1.0)/TiO₂ with a catalyst dosage normalized rate constant of 1.3 × 10^-2 L mg_cat^-1 min^-1, significantly more efficient than other catalytic treatment methods. The reactions proceeded in a highly selective manner towards catalytic hydrogenation at the CC bond of the Mdha moiety and subsequently the conjugated double bond of the Adda moiety, yielding two intermediates and one final product. Upon catalytic hydrogenation for 30 min on Pd(0.07)/TiO₂, the toxicity of MC-LR (assessed by protein phosphatase 2A activity assay) drastically decreased by 90.8%, demonstrating effective detoxification. The influence of catalyst support, Pd content, initial MC-LR concentration, reaction pH, and catalytic stability were examined. Surface adsorption and the cationic Pd played a crucial role in the reaction kinetics. Our results suggest that catalytic hydrogenation is a highly effective and safe strategy for detoxifying MC-LR by selective reactions.

Significant zinc release from widely-used commercial lithopone pigments under solar irradiation

Lithopone pigments are an important group of white inorganic pigments, with production exceeding 240,000 tons/year in China. Nevertheless, our understanding of its environmental behavior is still limited. In this work, we reported the fast and extensive release of Zn²⁺ from the commercial lithopone pigment under solar exposure. The lithopone pigment released 40.97% of its total Zn within 24-h simulated sunlight exposure, generating a significant amount of nanoparticles. The commercial lithopone pigment had bandgap energy of 3.63 eV. It can be excited within the solar spectrum (wavelength <342 nm). As suggested by the photocurrent and surface photovoltage results, the pigment generated electrons and holes with good separation and transfer efficiency upon solar irradiation. The pigment also produced hydroxyl radical and superoxide by the oxidation of surface-bound OH^- and H₂O by the holes and direct transfer of the electrons to oxygen molecules. The photogenerated holes can oxidize the pigment, leading to its photo-dissolution and consequently the release of Zn²⁺. The water chemistry, including pH, coexisting anions, and organic carbons, influenced the photo-dissolution kinetics of the pigment by changing the valence band edge, forming stable precipitates, competing for the holes, and screening effect. The release of Zn²⁺ from the commercial lithopone pigment was fast and extensive under natural conditions, with 35.16% Zn released within 6-h solar exposure. Our results highlighted the crucial role of photochemistry in the environmental risk assessments and regulations of commercial lithopone pigments.

Prediction of hydrophobic organic compound partition to algal organic matter through the growth cycle of Microcystis aeruginosa

Algal organic matter (AOM) is an important source for the dissolved organic matter (DOM) pool in aquatic systems, particularly in eutrophic waters. In this study, we reported the dynamic pattern of AOM hydrophobicity during the growth cycle of Microcystis aeruginosa using the partition coefficients of AOM in the aqueous two-phase system (K_ATPS) as a simple quantitative measure. AOM hydrophobicity had significant and non-monotonic changes during the growth cycle. It increased in the lag and early exponential phases, then decreased in the late exponential and stationary phases, and rebounded in the decline phase. AOM hydrophobicity determined using the resin fractionation, SUVA₂₅₄, and nuclear magnetic resonance methods shared similar non-monotonic pattern. Nevertheless, the correlations among these indicators were poor. The partition behavior of polycyclic aromatic hydrocarbons and chlorobenzenes to AOM was assessed based the K_ATPS dataset and the two-phase system (TPS) model. The TPS model showed good prediction power for the partition behavior of AOM with an RMSE of 0.23, suggesting that it was applicable to AOM from Microcystis aeruginosa. Our results indicate that algae activity will influence the overall hydrophobicity of the DOM pool depending on the growth phase, resulting in changes in the bioavailability of hydrophobic organic compounds in aquatic systems.

Octanol-water partition coefficient (logKow) dependent movement and time lagging of polycyclic aromatic hydrocarbons (PAHs) from emission sources to lake sediments: A case study of Taihu Lake, China

Understanding the movement of polycyclic aromatic hydrocarbons (PAHs) from emission sources to sediments is important for achieving long-term pollution control of PAHs in sediments. In this study, by exploring the correlation of individual PAHs concentrations (C_PAHs) in Taihu Lake sediments reported in the past twenty years with their annual emissions (E_PAHs) in the lake region, it was observed that mean concentrations of PAHs with low logK_ow (i.e., logK_ow≤4.00) in Taihu Lake sediments were correlated best with their emissions without lagging between the sediment sampling time and the PAHs emitting time. However, for PAHs with middle logK_ow (i.e., 4.00<logK_ow≤4.57) or high logK_ow (i.e., logK_ow>4.57), their mean concentrations in sediments were correlated best with the emissions of PAHs emitted 1 or 2 years before the sediment sampling time. The longer lagging time of PAHs with middle or high logK_ow from emission sources to lake sediments could be attributed to their retardation in soils and river sediments around the lake. Moreover, the retardation in soils and river sediments is dependent on PAHs logK_ow and degradation half-life, indicating the dependence of PAHs concentration in sediments on their environmental behaviors, including sorption and degradation. K_ow dependent movement and the time lagging observed in Taihu Lake for PAHs from emission sources to sediments could be valuable for developing measures to control PAHs, especially for congeners with high logK_ow.

High-Throughput Method for Natural Organic Matter Hydrophobicity Assessment Using an Ionic Liquid-Based Aqueous Two-Phase System

Hydrophobicity of natural organic matter (NOM) is one of its fundamental properties that influence the environmental fate of pollutants and the performance of many water treatment unit processes. In this study, a high-throughput method was developed for NOM hydrophobicity measurement based on the phase separation technique in the 96-well format. It measures the partition coefficients of NOM (K_ATPS,IL) in an ionic liquid (IL)-based aqueous two-phase system (ATPS). The ATPS was made of 1-butyl-3-methylimidazole bromide solution and a salt solution containing potassium phosphate monobasic and potassium phosphate dibasic. The partition of NOM in IL-based ATPS is mainly affected by its hydrophobicity. log K_ATPS,IL linearly correlated with the commonly used NOM hydrophobicity scales, including (O + N)/C, O/C, and aromatic carbons. K_ATPS,IL provided a more accurate assessment of NOM hydrophobicity than spectroscopic indices. Furthermore, K_ATPS,IL can predict the organic carbon-water partition coefficients for hydrophobic organic chemical sorption to NOM based on the two-phase system model. The high-throughput K_ATPS,IL measurement and the two-phase system model can be applied to real surface water samples. Our results suggest that the proposed high-throughput method has great potential to be applied to monitor NOM hydrophobicity for environmental risk assessment and water treatment purposes.

Screening and Discrimination of Perfluoroalkyl Substances in Aqueous Solution Using a Luminescent Metal-Organic Framework Sensor Array

The extensive production and large-scale use of perfluoroalkyl substances (PFASs) have raised their presence in aquatic environments worldwide. Thus, the facile and reliable screening of PFASs in aqueous systems is of great significance. Herein, we designed a novel fluorescent sensor array for the rapid screening and discrimination of multiple PFASs in water. The sensor array comprised three highly stable zirconium porphyrinic luminescent metal-organic frameworks (i.e., PCNs) with different topological structures. The sensing mechanism was based on the static fluorescence quenching of PCNs by PFASs upon their adsorptive interactions. The fluorescence response patterns were characteristic for each PFAS because of their different adsorption affinities toward different PCNs. Through the interpretation of response patterns by statistical methods, the proposed PCN array successfully discriminated six different kinds of PFASs, each PFAS at different concentrations and PFAS mixtures at different molar ratios. The practicability of this array was further verified by effectively discriminating PFASs in two real water samples. Remarkably, the PCN sensors exhibited a very short response time toward PFASs (within 10 s) due to the ordered pore structure allowing fast PFAS diffusion. This study not only provides a facile method for rapid PFAS screening in waters but also broadens the application of luminescent metal-organic frameworks and array techniques in sensing fields.

A Deep Learning-Based Automatic First-Arrival Picking Method for Ultrasound Sound-Speed Tomography

Ultrasound sound-speed tomography (USST) has shown great prospects for breast cancer diagnosis due to its advantages of nonradiation, low cost, 3-D breast images, and quantitative indicators. However, the reconstruction quality of USST is highly dependent on the first-arrival picking of the transmission wave. Traditional first-arrival picking methods have low accuracy and noise robustness. To improve the accuracy and robustness, we introduced a self-attention mechanism into the bidirectional long short-term memory (BLSTM) network and proposed the self-attention BLSTM (SAT-BLSTM) network. The proposed method predicts the probability of the first-arrival time and selects the time with maximum probability. A numerical simulation and prototype experiment were conducted. In the numerical simulation, the proposed SAT-BLSTM showed the best results. For signal-to-noise ratios (SNRs) of 50, 30, and 15 dB, the mean absolute errors (MAEs) were 48, 49, and 76 ns, respectively. The BLSTM had the second-best results, with MAEs of 55, 56, and 85 ns, respectively. The MAEs of the Akaike information criterion (AIC) method were 57, 296, and 489 ns, respectively. In the prototype experiment, the MAEs of the SAT-BLSTM, the BLSTM, and the AIC were 94, 111, and 410 ns, respectively.

Confined La2O3 particles in mesoporous carbon material for enhanced phosphate adsorption

Novel phosphate adsorbents with confined La2O3 inside mesoporous carbon were fabricated by the solid-state grinding method using pristine mesoporous carbon material CMK-3 (PCMK-3) and oxidized CMK-3 (OCMK-3) as the matrixes (denoted as La2O3@PCMK-3 and La2O3@OCMK-3). Compared with pure La2O3, La2O3@PCMK-3 and La2O3@OCMK-3 exhibited higher normalized phosphate adsorption capacity, indicative of efficient loading of La2O3 inside the mesopores of the carbon materials. Furthermore, La2O3 loading led to substantially enhanced phosphate adsorption. The adsorption capacities of La2O3@OCMK-3 samples were higher than those of La2O3@PCMK-3 samples, possibly owing to the oxygen-containing groups forming in OCMK-3 during HNO3 oxidation, which enhanced the dispersion of La2O3 in the mesopores of OCMK-3. The adsorption capacities of La2O3@PCMK-3 and La2O3@OCMK-3 increased with the La2O3 loading amount. Phosphate adsorption onto La2O3(14.7)@PCMK-3 followed the pseudo-second-order kinetics with respect to correlation coefficient values (larger than 0.99). As pH increased from 3.4 to 12.0, the phosphate adsorption amounts of La2O3(14.7)@PCMK-3 and La2O3(15.7)@OCMK-3 decreased from 37.64 mg g-1 and 37.08 mg g-1 to 21.92 mg g-1 and 14.18 mg g-1, respectively. Additionally, La2O3@PCMK-3 showed higher adsorption selectivity towards phosphate than coexisting Cl-,NO 3 - andSO 4 2 - . The adsorbent La2O3(14.7)@PCMK-3 remained stable after five regeneration cycles.

Spatial and seasonal patterns of dissolved organic matter hydrophobicity in Lake Taihu revealed by the aqueous two-phase system

The hydrophobicity of dissolved organic matter (DOM) is a key property influencing the environmental risks of organic pollutants. Our understanding of the spatial and seasonal pattern of DOM hydrophobicity in aquatic systems and the major controlling factors is still limited. In this study, the hydrophobicity of 124 DOM samples collected from northern Lake Taihu, a typical eutrophic lake, was quantified using the partition coefficient of DOM in the aqueous two-phase system (K_ATPS). The results revealed high-resolution spatial patterns and seasonal variations of DOM hydrophobicity in Lake Taihu. The riverine input, algae activity, and photodegradation were identified as important processes shaping the spatial and seasonal pattern of DOM hydrophobicity. The riverine input and algae activity strongly affected DOM hydrophobicity in the west part and the central area of the lake. Photodegradation process played a significant role in DOM hydrophobicity in the east part of the lake in summer. The high-resolution spatial and seasonal pattern of the hydrophobic organic pollutant partition affinity of DOM (K_OC) was assessed based on the two-phase system model and the K_ATPS dataset. The K_OC values vary significantly in Lake Taihu between spring and summer, especially in the Zhushan Bay and east coast areas, highlighting the need for considering DOM dynamics in sorption assessment. Our results detailly profiled the spatial and seasonal patterns of DOM hydrophobicity and sorption behavior and elucidated the major controlling factors, which is crucial for environmental risk assessment.

Efficient Reduction of Selenite to Elemental Selenium by Liquid-Phase Catalytic Hydrogenation Using a Highly Stable Multiwalled Carbon Nanotube-Supported Pt Catalyst Coated by N-Doped Carbon

A stable catalyst, Pt/carbon nanotube (CNT) coated with N-doped carbon (Pt/CNT@CN), was designed to reduce selenite (Se(IV)) in water to elemental selenium by liquid-phase catalytic hydrogenation. Commercial Pt/C, pristine Pt/CNT, and carbon-coated Pt/CNT (Pt/CNT@C) were used for benchmarking. The Pt particles in Pt/CNT@CN were completely embedded beneath the coatings to minimize leaching and were not easily accessible to Se(IV). However, Schottky-Mott-type metal-carbon junctions that activate H2 were formed on the coated catalyst, facilitating effective reduction of Se(IV). The initial activity of Pt/CNT@CN (900.5 mg L-1 gcat-1 h-1) was two times higher than that of commercial Pt/C (448.6 mg L-1 gcat-1 h-1). The commercial Pt/C and uncoated Pt/CNT lost their initial activities during reuse and were almost inactive after 10 cycles due to significant Pt leaching (>90%) during the reaction and acid-washing regeneration processes. Pt/CNT@CN maintained 33% of the initial activity after the first cycle and stabilized over the following 9 cycles due to effective protection of Pt particles by carbon coatings. After 10 cycles, the activity of Pt/CNT@CN was over 20 times higher than that of Pt/C and uncoated Pt/CNT. Overall, catalytic hydrogenation using carbon-coated-supported Pt catalysts is an effective and promising approach to remove Se(IV) in water.

Combined analyses of hygroscopic properties of organic and inorganic components of three representative black carbon samples recovered from pyrolysis

Hygroscopicity of black carbon (BC) aerosols is a key factor determining their climate forcing effect and atmospheric lifetime. However, the compositional dependence of BC hygroscopicity is not well understood. Here, a variety of different compositional components were separated from three representative BC samples recovered from pyrolysis (grass and wheat straw derived BC, household soot), including water extracted fraction of BC (WEBC, 9-21 wt%), residue fraction of BC after water extraction (R-WEBC, 79-91 wt%), water extracted minerals (WEM, 9-18 wt%), alkali extracted organic carbon (OC_AE, 1-9 wt%), and elemental carbon (EC, 37-48 wt%). The bulk BC and separated BC components were analyzed in detail by elemental analysis and combined spectroscopic analyses. Their equilibrium hygroscopicity was measured by gravimetric method over a range of relative humidity (RH) levels (10-94%). Compared with the two organic components (OC_AE and EC), the inorganic component (WEM) exhibited much stronger water uptake at all RH levels. At 94% RH level, WEM accounted for 16-139% of the overall water uptake by BC, whereas OC_AE and EC accounted for only 1-3% and 6-26%, respectively. The XRD analysis of WEBC and WEM from household soot at varying RH levels indicated that the enhanced water uptake by these two components as well as that by bulk BC at high RH levels was due to the deliquescent salts (e.g., KCl, NH₄Cl, KNO₃, and NaCl). The strong hysteresis loops observed for bulk BC and WEBC could be attributed to the organic-facilitated drastic structural and morphological rearrangement of mineral particles as evidenced by the optical microscope analysis. The diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) analysis reaffirmed the dominant role played by the inorganic component in the hygroscopic behaviors of BC.

The protective effect of hesperidin against renal ischemia-reperfusion injury involves the TLR-4/NF-κB/iNOS pathway in rats

Renal injury is reported to have a high mortality rate. Additionally, there are several limitations to current conventional treatments that are used to manage it. This study evaluated the protective effect of hesperidin against ischemia/reperfusion (I/R)-induced kidney injury in rats. Renal injury was induced by generating I/R in kidney tissues. Rats were then treated with hesperidin at a dose of 10 or 20 mg/kg intravenously 1 day after surgery for a period of 14 days. The effect of hesperidin on renal function, serum mediators of inflammation, and levels of oxidative stress in renal tissues were observed in rat kidney tissues after I/R-induced kidney injury. Moreover, protein expression and mRNA expression in kidney tissues were determined using Western blotting and RT-PCR. Hematoxylin and eosin (H&E) staining was done for histopathological observation of kidney tissues. The data suggest that the levels of blood urea nitrogen (BUN) and creatinine in the serum of hesperidin-treated rats were lower than in the I/R group. Treatment with hesperidin also ameliorated the altered level of inflammatory mediators and oxidative stress in I/R-induced renal-injured rats. The expression of p-IκBα, caspase-3, NF-κB p65, Toll-like receptor 4 (TLR-4) protein, TLR-4 mRNA, and inducible nitric oxide synthase (iNOS) was significantly reduced in the renal tissues of hesperidin-treated rats. Histopathological findings also revealed that treatment with hesperidin attenuated the renal injury in I/R kidney-injured rats. In conclusion, our results suggest that hesperidin protects against renal injury induced by I/R by involving TLR-4/NF-κB/iNOS signaling.