A Janus Textile with Tunable Heating Modes toward Precise Personal Thermal Management in Cold Conditions.

Passive heating textiles (PHTs) have drawn increasing attention due to the advantages of energy-conservation heating. However, the heating capabilities of current PHTs are typically static and non-tunable, presenting poor adaptation to dynamic winter. Herein, a novel Janus textile with tunable heating modes is developed by constructing a customized structure with asymmetric optical properties. This Janus textile is created by coating one side of a cotton fabric with silver nanowires (AgNWs) and then applying transition metal carbides/nitrides (MXene) to the other side. The MXene side exhibits high solar absorptivity and low mid-infrared emissivity, while the AgNWs side has moderate solar absorptivity and mid-infrared emissivity. This structure ensures that the solar and radiative heating temperatures of the MXene side are 16 °C and 1.7 °C higher than those of the AgNWs side. This distinction allows for on-demand, accurate adjustments in solar and radiative heating capabilities by flipping the textile according to ambient temperature. Furthermore, this innovative design also features desired electric heating, thermal camouflage, self-cleaning and antibacterial properties, electromagnetic interference shielding, durability, and wearability. The Janus textile enables precise thermoregulation of the human body to adapt to variable cold weather, making it essential for optimal personal thermal management and climate change mitigation.

An Asymmetric Layer Structure Enables Robust Multifunctional Wearable Bacterial Cellulose Composite Film with Excellent Electrothermal/Photothermal and EMI Shielding Performance.

Highly robust flexible multifunctional film with excellent electromagnetic interference shielding and electrothermal/photothermal characteristics are highly desirable for aerospace, military, and wearable devices. Herein, an asymmetric gradient multilayer structured bacterial cellulose@Fe3O4/carbon nanotube/Ti3C2Tx (BC@Fe3O4/CNT/Ti3C2Tx) multifunctional composite film is fabricated with simultaneously demonstrating fast Joule response, excellent EMI shielding effectiveness (EMI SE) and photothermal conversion properties. The asymmetric gradient 6-layer composite film with 40% of Ti3C2Tx possesses excellent mechanical performance with exceptional tensile strength (76.1 MPa), large strain (14.7%), and good flexibility. This is attributed to the asymmetric gradient multilayer structure designed based on the hydrogen bonding self-assembly strategy between Ti3C2Tx and BC. It achieved an EMI SE of up to 71.3 dB, which is attributed to the gradient "absorption-reflection-reabsorption" mechanism. Furthermore, this composite film also exhibits excellent low-voltage-driven Joule heating (up to 80.3 °C at 2.5 V within 15 s) and fast-response photothermal performance (up to 101.5 °C at 1.0 W cm-2 within 10 s), which is attributed to the synergistic effect of heterostructure. This work demonstrates the fabrication of multifunctional bacterial cellulose@Fe3O4/carbon nanotube/Ti3C2Tx composite film has promising potentials for next-generation wearable electronic devices in energy conversion, aerospace, and artificial intelligence.

Risk of anthracycline-induced cardiac dysfunction in adolescent and young adult (AYA) cancer survivors: role of genetic susceptibility loci.

There is a known genetic susceptibility to anthracycline-induced cardiac dysfunction in childhood cancer survivors, but this has not been adequately shown in adolescent and young adult (AYA) patients. Our aim was to determine if the previously identified variants associated with cardiac dysfunction in childhood cancer patients affect AYA cancer patients similarly. Forty-five variants were selected for analysis in 253 AYAs previously treated with anthracyclines. We identified four variants that were associated with cardiac dysfunction: SLC10A2:rs7319981 (p = 0.017), SLC22A17:rs4982753 (p = 0.019), HAS3:rs2232228 (p = 0.023), and RARG:rs2229774 (p = 0.050). HAS3:rs2232228 and SLC10A2:rs7319981 displayed significant effects in our AYA cancer survivor population that were in the opposite direction than that reported in childhood cancer survivors. Genetic variants in the host genes were further analyzed for additional associations with cardiotoxicity in AYA cancer survivors. The host genes were then evaluated in a panel of induced pluripotent stem cell-derived cardiomyocytes to assess changes in levels of expression when treated with doxorubicin. Significant upregulation of HAS3 and SLC22A17 expression was observed (p < 0.05), with non-significant anthracycline-responsivity observed for RARG. Our study demonstrates that there is a genetic influence on cardiac dysfunction in AYA cancer patients, but there may be a difference in the role of genetics between childhood and AYA cancer survivors.

Novel serum biomarker of Golgi protein 73 for the diagnosis of clinically significant portal hypertension in patients with compensated cirrhosis.

Hepatic venous pressure gradient (HVPG) is the gold standard for evaluating clinically significant portal hypertension (CSPH). However, reliable noninvasive methods are limited. Our study aims to investigate the diagnostic value of serum Golgi protein 73 (GP73) for CSPH in patients with compensated cirrhosis. The study enrolled 262 consecutive patients with compensated cirrhosis from three centers in China from February 2021 to September 2023, who underwent both serum GP73 tests and HVPG measurements. CSPH was defined as HVPG ≥ 10 mmHg. Diagnostic accuracy was evaluated using the areas under the receiver operating characteristic curve (AUC). The prevalence of CSPH was 56.9% (n = 149). There were significant differences between the CSPH and non-CSPH groups in the median serum GP73 level (126.8 vs. 73.1 ng/mL, p < 0.001). GP73 level showed a significant positive linear correlation with HVPG (r = 0.459, p < 0.001). The AUC for the diagnosis of CSPH using serum GP73 alone was 0.75 (95% confidence interval [CI] 0.68-0.81). Multivariate logistic regression analysis determined that the levels of GP73, platelets and international normalized ratio were independently associated with CSPH. The combination of these three markers was termed "IP73" score with an AUC value of 0.85 (95% CI 0.80-0.89) for CSPH. Using 0 as a cut-off value, the specificity and sensitivity of IP73 score were 77.9% and 81.9%, respectively. The IP73 score offers a novel, simple and noninvasive method of assessing CSPH in patients with compensated cirrhosis. A cut-off value of the IP73 score at 0 can distinguish patients with or without CSPH.

Ultralight Flexible Collagen Fiber Based Aerogels Derived from Leather Solid Waste for High Electromagnetic Interference Shielding.

Designing and developing high-performance shielding materials against electromagnetic interference is of utmost importance due to the rapid advancement of wireless telecommunication technologies. Such materials hold both fundamental and technological significance. A three-stage process is presented for creating ultralight, flexible aerogels from biomass to shield against electromagnetic interference. Collagen fibers sourced from leather solid waste are used for: (i) freeze-drying preparation of collagen fibers/poly(vinyl alcohol) (PVA) aerogels, (ii) adsorption of silver nanowires (AgNWs) onto collagen fiber/PVA aerogels, and (iii) Hydrophobic modification of collagen fiber/PVA/AgNWs aerogels with 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane (POTS). Scanning electron microscopy studies reveal that an interweaving of AgNWs and collagen fiber/PVA porous network has formed a conductive network, exhibiting an electrical conductivity of 103 S·m-1. The electromagnetic interference shielding effectiveness reached more than 62 dB, while the density was merely 5.8 mg/cm3. The collagen fiber/PVA/AgNWs/POTS aerogel displayed an even better electromagnetic shielding efficiency of 73 dB and water contact angle of 147°. The study results emphasize the distinctive capacity of leather solid waste to generate cost-effective, ecofriendly, and highly efficient electromagnetic interference shielding materials.

Visual and rapid fluorescence sensing for hexavalent chromium by hydroxypropyl chitosan passivated bismuth-based perovskite quantum dots.

Hydroxypropyl chitosan-Cs3Bi2Cl9 perovskite quantum dots (HPCS-PQDs) were synthesized by a simple ligand-assisted reprecipitation method via green hydroxypropyl chitosan as the ligand and used as the specific signal of a fluorescence probe to achieve the highly sensitive detection of hexavalent chromium (Cr(VI)) and compared with chitosan-Cs3Bi2Cl9 QDs (CS-PQDs). HPCS-PQDs with multiple active hydroxyl passivations were found to enhance the photoluminescence quantum yield (PLQY) by 90%. After being placed in aqueous solution and irradiated with ultraviolet light for 96 h the fluorescence intensity of HPCS-PQDs remained above 60%. The blue emission of HPCS-PQDs has a good selectivity and short response time (30 s) for Cr(VI). A good linear relationship is established between the fluorescence quenching rate of the HPCS-PQDs and concentration of Cr(VI) from 0.8 to 400 µM, with a limit of detection (LOD) of 0.27 µM. The fluorescence quenching mechanism is the static quenching and internal filtration effect caused by HPCS-PQDs forming a non-fluorescent ground-state complex with Cr(VI). The sensor can not only be used to detect Cr(VI) in water samples with high accuracy but can also be prepared as a test paper for the detection for Cr(VI).

Zebrafish nos2a benefits bacterial proliferation via suppressing ROS and inducing NO production to impair the expressions of inflammatory cytokines and antibacterial genes.

The enzyme nitric oxide synthase 2 or inducible NOS (NOS2), reactive oxygen species (ROS) and nitric oxide (NO) are important participants in various inflammatory and immune responses. However, the functional significances of the correlations among piscine NOS2, ROS and NO during pathogen infection remain unclear. In teleost, there are two nos2 genes (nos2a and nos2b). It has been previously reported that zebrafish nos2a behaves as a classical inducible NOS, and nos2b exerts some functions similar to mammalian NOS3. In the present study, we reported the functional characterization of zebrafish nos2a during bacterial infection. We found that zebrafish nos2a promoted bacterial proliferation, accompanied by an increased susceptibility to Edwardsiella piscicida infection. The nagative regulation of zebrafish nos2a during E. piscicida infection was characterized by the impaired ROS levels, the induced NO production and the decreased expressions of proinflammatory cytokines, antibacterial genes and oxidant factors. Furthermore, although both inducing ROS and inhibiting NO production significantly inhibited bacterial proliferation, only inhibiting NO production but not inducing ROS significantly increased resistance to E. piscicida infection. More importantly, ROS supplementation and inhibition of NO completely abolished this detrimental consequence mediated by zebrafish nos2a during E. piscicida infection. All together, these results firstly demonstrate that the innate response mediated by zebrafish nos2a in promoting bacterial proliferation is dependent on the lower ROS level and higher NO production. The present study also reveals that inhibition of NO can be effective in the protection against E. piscicida infection.

MAX-DOAS Measurements of Tropospheric NO2 and HCHO Vertical Profiles at the Longfengshan Regional Background Station in Northeastern China.

The vertical profiles of nitrogen dioxide (NO2) and formaldehyde (HCHO) in the troposphere at the Longfengshan (LFS) regional atmospheric background station (127°36' E, 44°44' N, 330.5 m above sea level) from 24 October 2020 to 13 October 2021 were retrieved from solar scattering spectra by multi-axis differential optical absorption spectroscopy (MAX-DOAS). We analyzed the temporal variations of NO2 and HCHO as well as the sensitivity of ozone (O3) production to the concentration ratio of HCHO to NO2. The largest NO2 volume mixing ratios (VMRs) occur in the near-surface layer for each month, with high values concentrated in the morning and evening. HCHO has an elevated layer around the altitude of 1.4 km consistently. The means ± standard deviations of vertical column densities (VCDs) and near-surface VMRs were 4.69 ± 3.72 ×1015 molecule·cm-2 and 1.22 ± 1.09 ppb for NO2, and they were 1.19 ± 8.35 × 1016 molecule·cm-2 and 2.41 ± 3.26 ppb for HCHO. The VCDs and near-surface VMRs for NO2 were high in the cold months and low in the warm months, while HCHO presented the opposite. The larger near-surface NO2 VMRs appeared in the condition associated with lower temperature and higher humidity, but this relationship was not found between HCHO and temperature. We also found the O3 production at the Longfengshan station was mainly in the NOx-limited regime. This is the first study presenting the vertical distributions of NO2 and HCHO in the regional background atmosphere of northeastern China, which are significant to enhancing the understanding of background atmospheric chemistry and regional ozone pollution processes.

Studies on the interactions of AFPs and bZIP transcription factor ABI5.

AFP1 interacts with ABI5 and negatively regulates the abscisic acid (ABA) signaling by accelerating ABI5's degradation during the seed germination phase in Arabidopsis, but the underlying mechanism remains unclear. Moreover, the molecular basis of the interaction between AFP1 homologs and ABI5 has yet to be elucidated. In this study, the patterns of their interactions with ABI5 were investigated in detail. We found that AFP2/3/4 can bind two regions of ABI5, one is ABI51aa to 135aa and another is ABI5202aa to 213aa. However, AFP1 only interacts with the second region of ABI5, i.e. ABI5202aa to 213aa. Prior research has shown that ABI51aa to 135aa is related to the transcriptional activity of ABI5. Thus, our results suggest that AFPs may also modulate ABI5, by directly binding to its transcriptional activation domain, thereby influencing its transcriptional activity. Further, interactions between AFPs and ABI5 were not affected if the Ser42th in the ABI5-SnRK2 motif were mutated respectively to Glu or Ala. Nevertheless, interactions between AFPs and ABI5 were eliminated if the Thr47th and Thr206th of ABI5 were mutated respectively to Glu or Ala. Since the two residues of Thr47th and Thr206th were located in the phosphorylation motifs of CKII, AFPs might regulate the activities of ABI5 transcription factor through a CKII-dependent pathway.

A Novel SAVE Score to Stratify Decompensation Risk in Compensated Advanced Chronic Liver Disease (CHESS2102): An International Multicenter Cohort Study.

INTRODUCTION: In patients with compensated advanced chronic liver disease (cACLD), the invasive measurement of hepatic venous pressure gradient is the best predictor of hepatic decompensation. This study aimed at developing an alternative risk prediction model to provide a decompensation risk assessment in cACLD. METHODS: Patients with cACLD were retrospectively included from 9 international centers within the Portal Hypertension Alliance in China (CHESS) network. Baseline variables from a Japanese cohort of 197 patients with cACLD were examined and fitted a Cox hazard regression model to develop a specific score for predicting hepatic decompensation. The novel score was validated in an external cohort (n = 770) from 5 centers in China, Singapore, Korea, and Egypt, and was further assessed for the ability of predicting clinically significant portal hypertension in a hepatic venous pressure gradient cohort (n = 285). RESULTS: In the derivation cohort, independent predictors of hepatic decompensation were identified including Stiffness of liver, Albumin, Varices, and platElets and fitted to develop the novel score, termed "SAVE" score. This score performed significantly better (all P < 0.05) than other assessed methods with a time-dependent receiver operating characteristic curve of 0.89 (95% confidence interval [CI]: 0.83-0.94) and 0.83 (95% CI: 0.73-0.92) in the derivation and validation cohorts, respectively. The decompensation risk was best stratified by the cutoff values at -6 and -4.5. The 5-year cumulative incidences of decompensation were 0%, 24.9%, and 69.0% in the low-risk, middle-risk, and high-risk groups, respectively ( P < 0.001). The SAVE score also accurately predicted clinically significant portal hypertension (AUC, 0.85 95% CI: 0.80-0.90). DISCUSSION: The SAVE score can be readily incorporated into clinical practice to accurately predict the individual risk of hepatic decompensation in cACLD.

Identification of Key Genes during Ca2+-Induced Genetic Transformation in Escherichia coli by Combining Multi-Omics and Gene Knockout Techniques.

The molecular mechanism of the Ca2+-mediated formation of competent cells in Escherichia coli remains unclear. In this study, transcriptome and proteomics techniques were used to screen genes in response to Ca2+ treatment. A total of 333 differentially expressed genes (317 upregulated and 16 downregulated) and 145 differentially expressed proteins (54 upregulated and 91 downregulated) were obtained. These genes and proteins are mainly enriched in cell membrane components, transmembrane transport, and stress response-related functional terms. Fifteen genes with these functions, including yiaW, ygiZ, and osmB, are speculated to play a key role in the cellular response to Ca2+. Three single-gene deletion strains were constructed with the Red homologous recombination method to verify its function in genetic transformation. The transformation efficiencies of yiaW, ygiZ, and osmB deletion strains for different-size plasmids were significantly increased. None of the three gene deletion strains changed in size, which is one of the main elements of microscopic morphology, but they exhibited different membrane permeabilities and transformation efficiencies. This study demonstrates that Ca2+-mediated competence formation in E. coli is not a simple physicochemical process and may involve the regulation of genes in response to Ca2+. This study lays the foundation for further in-depth analyses of the molecular mechanism of Ca2+-mediated transformation. IMPORTANCE Using transcriptome and proteome techniques and association analysis, we identified several key genes involved in the formation of Ca2+-mediated E. coli DH5α competent cells. We used Red homologous recombination technology to construct three single-gene deletion strains and found that the transformation efficiencies of yiaW, ygiZ, and osmB deletion strains for different-size plasmids were significantly increased. These results proved that the genetic transformation process is not only a physicochemical process but also a reaction process involving multiple genes. These results suggest ways to improve the horizontal gene transfer mechanism of foodborne microorganisms and provide new ideas for ensuring the safety of food preservation and processing.

Highly Stable CsSnCl3 Quantum Dots Grown in an Ionic Liquid/Gelatin Composite System through an In Situ Method.

Lead halide perovskite quantum dots (QDs) are controversial due to their high lead content. Tin, a low-toxic element with an outer electronic structure similar to that of Pb, becomes a strong candidate for preparing lead-free perovskite QDs. However, tin-based perovskite QDs, especially CsSnCl3 QDs, exhibit poor environmental stability. Herein, we proposed an strategy for highly stable CsSnCl3 QDs using an ionic liquid as a solvent and antioxidant and gelatin as a multidentate ligand and coating material through an in situ method ([AMIM]Cl/gelatin-QDs). The results showed that the abundant active groups of gelatin served as the nucleation growth center for QDs and further passivated QDs. At the same time, the long molecular chain of gelatin can coat the QDs to isolate the environment and fully protect QDs, and the size of QDs grown in gelatin was 5-10 nm. In addition, the oxidation resistance of ionic liquids and the halogen-rich environment formed also played an important role. Even if [AMIM]Cl/gelatin-QDs were treated with water and ultraviolet light simultaneously, its remaining fluorescence intensity was still above 60% within 72 h. Meaningfully, QDs endowed the composite system mildew resistance, which can resist the erosion of gelatin by molds, thereby realizing the system's long-term protection toward CsSnCl3 QDs.

Encapsulation of Pb-Free CsSnCl3 Perovskite Nanocrystals with Bone Gelatin: Enhanced Stability and Application in Fe3+ Sensing.

The toxicity of the Pb element limits the large-scale application of inorganic cesium-lead halide (CsPbX3, with X = Cl, Br, and I) perovskite nanocrystals (NCs). Pb-free cesium-tin halide (CsSnX3) NCs have emerged as a viable alternative because of its excellent photoelectric conversion efficiency. However, the applications are hampered by its poor stability and low photoluminescence quantum yield (PLQY). In this study, extraordinarily stable CsSnCl3 NCs were prepared by exploiting bone gelatin as surface capping agents, which retain 95% of the photoluminescence intensity in water for 55 h. Additionally, after bone gelatin encapsulation, the PLQY of CsSnCl3 NCs was found to increase from 2.17% to 3.13% for the uncapped counterparts because of an improved radiative recombination rate. With such remarkable optical properties of the bone gelatin-CsSnCl3 NCs, metal ions like Fe3+ in aqueous solutions can be readily detected and monitored, signifying the potential application of such stable bone gelatin-CsSnCl3 NCs in the development of fluorescence sensors and detectors.

Flame-Retardant PEDOT:PSS/LDHs/Leather Flexible Strain Sensor for Human Motion Detection.

Flexible piezoresistive sensors have demonstrated great potential in human-motion-detection applications. However, it still remains a challenge to fabricate strain sensors with high sensitivity, broad sensing range, and good linear response to strain. In this report, a simple and scalable fabrication strategy is developed to construct high performance strain sensors by using leather as the substrates to filtrate poly(3,4-ethylenedioxythiophene): poly(4-styrenesulfonate) (PEDOT:PSS) modified layered double hydroxides (LDHs) suspensions. The naturally aligned collagen fibers in leather enable size selection for the 2D conductive materials and as such dual-conductive pathways are effectively formed on the surface and in the matrix of leather. Due to the unique design of conductive networks, the prepared sensor possesses high gauge factor (maximum value of 2326.84), tunable strain range (0-70%), fast tensile response time (160 ms), and good stability in 1000 stretching-relaxing/compression-relaxing cycles, making it suitable for various human motion detections including coughing and large-scale motions of joint bending. In addition, the incorporated LDHs is a non-toxic flame retardant, which is helpful to reduce electronic fire risk and can bring added value to the sensor.

Functionally oriented analysis of cardiometabolic traits in a trans-ethnic sample.

Interpretation of genetic association results is difficult because signals often lack biological context. To generate hypotheses of the functional genetic etiology of complex cardiometabolic traits, we estimated the genetically determined component of gene expression from common variants using PrediXcan (1) and determined genes with differential predicted expression by trait. PrediXcan imputes tissue-specific expression levels from genetic variation using variant-level effect on gene expression in transcriptome data. To explore the value of imputed genetically regulated gene expression (GReX) models across different ancestral populations, we evaluated imputed expression levels for predictive accuracy genome-wide in RNA sequence data in samples drawn from European-ancestry and African-ancestry populations and identified substantial predictive power using European-derived models in a non-European target population. We then tested the association of GReX on 15 cardiometabolic traits including blood lipid levels, body mass index, height, blood pressure, fasting glucose and insulin, RR interval, fibrinogen level, factor VII level and white blood cell and platelet counts in 15 755 individuals across three ancestry groups, resulting in 20 novel gene-phenotype associations reaching experiment-wide significance across ancestries. In addition, we identified 18 significant novel gene-phenotype associations in our ancestry-specific analyses. Top associations were assessed for additional support via query of S-PrediXcan (2) results derived from publicly available genome-wide association studies summary data. Collectively, these findings illustrate the utility of transcriptome-based imputation models for discovery of cardiometabolic effect genes in a diverse dataset.

Hierarchical Incorporation of Surface-Functionalized Laponite Clay Nanoplatelets with Type I Collagen Matrix.

Unraveling the interaction mechanisms of type I collagen with various inorganic nanoparticles is of pivotal importance to construct collagen-based bionanocomposites with hierarchical structures for biomedical, pharmaceutical, and other industrial applications. In this study, synthetic two-dimensional Laponite nanoplatelets (LAP NPs) are surface-functionalized with tetrakis(hydroxymethyl) phosphonium sulfate (THPS) for reinforcing their incorporation with type I collagen matrix by focusing on the influences of the interactions on the hierarchical structures of the collagen. Our results indicate that the LAP NPs can be successfully surface-functionalized with THPS via covalent bonds between the amine-functionalized NPs and the hydroxymethyl groups of THPS. Moreover, the resulting NPs can be well dispersed into the collagen matrix and evenly bound onto the collagen fiber strands and between the collagen fibrils, preserving the native D-periodic banding patterns of the collagen fibrils. The formation of covalent and hydrogen bonds between the collagen and the functionalized NPs can stabilize the intrinsic triple-helical conformation of the collagen, conferring the resulting collagen-based nanocomposites with improved thermal stability and enhanced mechanical properties. We anticipate that a fundamental understanding of the interactions between the collagen and functionalized inorganic nanoparticles would contribute to the design, fabrication, and further application of hierarchical collagen-based bionanocomposites with multifunctions.

Photochemical Formation of Methylhydroperoxide in Dissolved Organic Matter Solutions.

Although it is known that the solar irradiation of chromophoric dissolved organic matter (CDOM) solutions generates H2O2, whether or not organic hydroperoxides (ROOHs) are photochemically formed remains unclear. This study employs high-performance liquid chromatography with the postcolumn enzymatic derivatization method to examine whether ROOHs can be formed in CDOM solutions under simulated solar irradiation. Methylhydroperoxide (MHP) is the only identified ROOH under our experimental conditions, and the quantum yields of MHP (ΦMHP) vary from (1.09 ± 0.09) × 10-6 to (4.95 ± 0.11) × 10-6 in the tested CDOM solutions, including four reference natural organic matters and two effluent organic matters. The quantum yields of H2O2 (ΦH2O2) are simultaneously measured, and the ratios of ΦH2O2 to ΦMHP range from 147 to 676. The formation of MHP is highly related to the presence of superoxide radical ions (O2•-) and methyl radicals (CH3•); therefore, a photoformation mechanism of MHP has been proposed. The photochemically generated CH3• reacts with O2 to yield CH3OO•. Subsequently, CH3OO• is reduced to MHP by O2•-. Our results also suggest that the yield of CH3• to MHP under air-saturated conditions is 52% and increases to 98% under oxygen-saturated conditions. The decays of MHP and H2O2 are very similar in terms of photodegradation, hydrolysis, Fenton, and photo-Fenton reactions. This study can be useful to understand the photochemical formation of organic peroxides in surface waters.

Enhanced Antistatic and Self-Heatable Wearable Coating with Self-Tiered Structure Caused by Amphiphilic MXene in Waterborne Polymer.

The antistatic and self-heatable flexible coating is highly desired for next-generation multifunctional clothing. MXene is a promising filler that possesses an excellent conductivity, an efficient photothermal conversion, and an outstanding compatibility with the waterborne polymer. In this study, MXene was integrated with waterborne polyacrylate by a solution-blending method. The polyacrylate/MXene composites display a self-tiered structure, and the composite coated leather possesses a surface resistivity of 7.85 × 109 Ω with 2 wt % loading, satisfying the B-level of the antistatic standard. The polyacrylate/MXene-0.5 wt % shows a higher temperature increase of 46.9 °C than that of pure polyacrylate after being irradiated by a 275 W IR light for 5 min, and the surface temperature of polyacrylate/MXene-0.5 wt % composite coated leather is 5.4 °C higher than that of polyacrylate coated leather after being irradiated by sunlight for 30 min. The tensile strength of the polyacrylate/MXene-1 wt % composite is increased by 28.3% compared with that of pure polyacrylate. All of the results prove its promising application in the multifunctional coating. Moreover, amphiphilic MXene was produced by changing the etching degree, which resulted in a self-tiered structure of the polyacrylate/MXene composite owing to the improved interfacial activity of MXene. The amphiphilic MXene possesses a decreased surface tension and can serve as a stabilizer for a Pickering emulsion, which suggests novel routes for constructing a multifunctional polymer/MXene composite.

Triplet Photochemistry of Dissolved Black Carbon and Its Effects on the Photochemical Formation of Reactive Oxygen Species.

Dissolved black carbon (DBC) is an important component of dissolved organic matter pool; however, its photochemical properties are not fully understood. In this study, we determined the excited triplet-state quantum yields of DBC (3DBC*) and 1O2 quantum yields (Φ1O2) of six diverse DBCs using sorbic alcohol, 2,4,6-trimethylphenol (TMP), and furfuryl alcohol and compared the results with quantum yields of reference natural organic matters (NOMs). The average Φ1O2 of six DBCs (4.2 ± 1.5%) was greater than that of terrestrial NOM (2.4 ± 0.3%) and comparable to autochthonous NOM (5.3 ± 0.2%). Using TMP as a probe for oxidizing triplets, DBC presented significantly higher apparent quantum yield coefficients for degrading TMP (fTMP) than the reference NOM, reflecting that the fTMP values of low-energy 3DBC* were approximately 12-fold greater than those of low-energy 3NOM*. The differences in the fTMP and Φ1O2 trends among the DBCs indicated that the 3DBC* responsible for these reactions may be from different sources. In addition, DBC was much more effective than NOM, on a carbon-normalized basis, during photodegradation of pharmaceutically active compounds. This result confirms that the presence of DBC can accelerate the photodegradation of contaminants that are susceptible to one-electron oxidation by triplets.

Carbonate Radical Oxidation of Cylindrospermopsin (Cyanotoxin): Kinetic Studies and Mechanistic Consideration.

Cylindrospermopsin (CYN) is one of the most important cyanobacterial toxins frequently found in surface waters. We reported the detailed kinetics and pathways for the reaction of CYN with carbonate radicals (CO3•-). The rate constants of neutral and deprotonated CYN with CO3•- were found to be (1.2 ± 0.7) × 107 M-1 s-1 and (3.0 ± 0.4) × 108 M-1 s-1, respectively. The transformation products for the oxidation of CYN by CO3•- were identified by high-resolution mass spectrometry, illustrating that the guanidine and bridged hydroxyl portions were the primary moieties attacked by CO3•-. Thus, three transformation pathways, including cleavage of the hydroxymethyluracil moiety, hydroxylation, and oxidation of the bridged hydroxyl group, are proposed for the CO3•- oxidation of CYN. Moreover, this study reported that dissolved organic matter (DOM) reduced the transformation rate of CYN by inhibiting the transformation of oxidation intermediates. Finally, the role of CO3•- in CYN degradation was estimated in both sunlit surface waters and advanced oxidation processes (AOPs), demonstrating that CO3•- played an important role in CYN attenuation under nonacidic environmentally relevant conditions. The kinetic parameters and product information obtained in this study will be of considerable interest for the application of AOPs and predicting the environmental fate of CYN.