Hierarchically Responsive Alternating Nano-Copolymers with Tailored Interparticle Bonds.

Self-assembly of inorganic nanoparticles (NPs) is an essential tool for constructing structured materials with a wide range of applications. However, achieving ordered assembly structures with externally programmable properties in binary NP systems remains challenging. In this work, we assemble binary inorganic NPs into hierarchically pH-responsive alternating copolymer-like nanostructures in an aqueous medium by engineering the interparticle electrostatic interactions. The polymer-grafted NPs bearing opposite charges are viewed as nanoscale monomers ("nanomers"), and copolymerized into alternating nano-copolymers (ANCPs) driven by the formation of interparticle "bonds" between nanomers. The resulting ANCPs exhibit reversibly responsive "bond" length (i.e., the distance between nanomers) in response to the variation of pH in a range of ~7-10, allowing precise control over the surface plasmon resonance of ANCPs. Moreover, specific interparticle "bonds" can break up at pH≥11, leading to the dis-assembly of ANCPs into molecule-like dimers and trimers. These dimeric and trimeric structures can reassemble to form ANCPs owing to the resuming of interparticle "bonds", when the pH value of the solution changes from 11 to 7. The hierarchically responsive nanostructures may find applications in such as biosensing, optical waveguide, and electronic devices.

Photo-Induced Self-assembly of Copolymer-Capped Nanoparticles into Colloidal Molecules.

Colloidal molecules (CMs) are precisely defined assemblies of nanoparticles (NPs) that mimic the structure of real molecules, but externally programming the precise self-assembly of CMs is still challenging. In this work, we show that the photo-induced self-assembly of complementary copolymer-capped binary NPs can be precisely controlled to form clustered ABx or linear (AB)y CMs at high yield (x is the coordination number of NP-Bs, and y is the repeating unit number of AB clusters). Under UV light irradiation, photolabile p-methoxyphenacyl groups of copolymers on NP-A*s are converted to carboxyl groups (NP-A), which react with tertiary amines of copolymers on NP-B to trigger the directional NP bonding. The x value of ABx can be precisely controlled between 1 and 3 by varying the irradiation duration and hence the amount of carboxyl groups generated on NP-As. Moreover, when NP-A* and NP-B are irradiated after mixing, the assembly process generates AB clusters or linear (AB)y structures with alternating sequence of the binary NPs. This assembly approach offers a simple yet non-invasive way to externally regulate the formation of various CMs on demand without the need of redesigning the surface chemistry of NPs for use in drug delivery, diagnostics, optoelectronics, and plasmonic devices.

Has China's carbon market stress released? Measurement and comparison of national and pilot carbon markets' stress.

This paper constructs a novel stress measurement system of carbon market from the perspective of trading, emission reduction, and external shocks and simulates the stress indices of national and pilot carbon markets of China with the methods of functional data analysis and criteria importance through intercriteria correlation. It concludes that the overall carbon market stress is in the shape of "W" and still at a high level, with frequent fluctuations and an upward trend. In addition, the stress of Hubei, Beijing, and Shanghai carbon market fluctuates and rises, while the stress of Guangdong carbon market decreases. Moreover, carbon market stress mainly comes from trading and emission reduction. Furthermore, stress fluctuation of Guangdong and Beijing carbon market is more prone to "big waves," indicating that the two markets are sensitive to big events. Finally, the pilot carbon markets are divided into stress-driven and stress-release market and the type of which keeps change in different period.

Pyrocatechol Alleviates Cisplatin-Induced Acute Kidney Injury by Inhibiting ROS Production.

As one of the most common cancer chemotherapy drugs, cisplatin is widely used in cancer management. However, cisplatin-induced nephrotoxicity occurs in patients who receive this drug. This study is aimed at developing therapeutic agents that effectively alleviate the nephrotoxic effects during cisplatin treatment. We identified a compound named pyrocatechol (PCL) from a natural product library that significantly alleviated cisplatin-induced cytotoxicity in vitro. Pyrocatechol treatment substantially ameliorated cisplatin (20 mg · kg-1) treatment-induced neuropathological indexes, including inflammatory cell infiltration and apoptosis, in vivo. Mechanistically, pyrocatechol significantly prevented oxidative stress-induced apoptosis by activating glutathione peroxidase 4 (GPX4) to reduce reactive oxygen species (ROS) accumulation in cisplatin-treated cells. In addition, pyrocatechol significantly inhibited ROS-induced JNK/P38 activation. Thus, we found that pyrocatechol prevents ROS-mediated JNK/P38 MAPK activation, apoptosis, and cytotoxicity through GPX4. Our study demonstrated that pyrocatechol is a novel therapeutic agent against cisplatin-induced kidney injury.

Electrostatic Adsorption Behaviors of Charged Polymer-Tethered Nanoparticles on Oppositely Charged Surfaces.

Polymer-grafted hairy nanoparticles (HNPs) that combine the unique properties of inorganic nanoparticles (NPs) and polymers are attractive building blocks for the layer-by-layer assembly of functional hybrid materials, but the adsorption behaviors of HNPs on substrates remain unclear. This article describes a systematic study on the adsorption behaviors of charged polymer-grafted HNPs on oppositely charged substrates in different solvent media via a combination of experiments and simulations. It is shown in simulations that the adsorption process of HNPs is associated with the release of counterions around charged polymers on HNPs, thus resulting in a higher energy barrier of NP adsorption than bare NPs without charged polymer tethers. This energy barrier decreases with decreasing the dielectricity of solvents or ionization degree of grafted polymers or increasing ionic strength of the solution. Furthermore, the theoretical prediction is confirmed in experiments by using a model system of poly(acrylic acid)-grafted silica NPs and poly(diallyldimethylammonium chloride)-modified wafers. The work provides guidance for the electrostatic assembly of HNPs into functional hybrid composites with applications in membranes, optical devices, and biomedicines.

Development and validation of a novel nomogram for predicting systemic inflammatory response syndrome's occurrence in patients undertaking flexible ureteroscopy.

Background: The occurrence of systemic inflammatory response syndrome (SIRS) is an early alert for sepsis after flexible ureteroscopy (fURS). Once sepsis occurs, it often leads to severe or fatal consequences. We aimed to identify SIRS patients preoperatively by developing and validating a feasible prognostic nomogram model based on retrospective cohort analysis. Methods: A total of 311 patients who underwent fURS in Dongguan Kanghua Hospital (Dongguan, China) between 2016 and 2020 were included and randomly divided into a primary cohort (n=219) and validation cohort (n=92). Single factor regression analysis was used to identify the primary cohort's meaningful characters between SIRS and non-SIRS groups. Factors of the primary cohort were then identified by least absolute shrinkage and selection operator (LASSO) regression analysis, and a nomogram was built to execute the subsequent analysis using these factors. Finally, we analyzed and drew the calibration curve, receiver operating characteristic (ROC) curve, and decision curve analysis (DCA) curve to validate the prognostic value of the nomogram in calibration and discrimination. Results: Review of the single regression analysis of characters in the primary cohort showed gender, stone burden, diabetes, neutrophil (N), lymphocyte (L), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), lymphocyte-to-monocytes ratio (LMR), urine-WBC, nitrite (Nit), urine culture, and surgery time as significant factors between the SIRS and non-SIRS groups (P<0.05). The LASSO regression analysis suggested NLR, PLR, and urine culture were substantial factors in predicting SIRS postoperatively, lambda.min and lambda.1se (standard error, SE) were 0.01491 and 0.0796. A nomogram built with the three factors showed good calibration and discrimination, with the Brier values 0.064 and 0.034 and the area under curve (AUC) values 0.897 (95% CI: 0.837-0.957) and 0.976 (95% CI: 0.947-1.000) in the primary and validation cohort, respectively. DCA demonstrated the nomogram was clinically useful, and the predict probability of SIRS's occurrence was very close to the actual rate as the risk threshold increased by higher than 60% in clinical impact curve analysis. Conclusions: NLR, PLR, and urine culture were significantly related to the occurrence of SIRS's after fURS. The nomogram with these three factors showed excellent calibration, discrimination, and clinical usefulness.

Reversible Self-Assembly of Gold Nanoparticles Based on Co-Functionalization with Zwitterionic and Cationic Binding Motifs*.

We report a pH- and temperature-controlled reversible self-assembly of Au-nanoparticles (AuNPs) in water, based on their surface modification with cationic guanidiniocarbonyl pyrrole (GCP) and zwitterionic guanidiniocarbonyl pyrrole carboxylate (GCPZ) binding motifs. When both binding motifs are installed in a carefully balanced ratio, the resulting functionalized AuNPs self-assemble at pH 1, pH 7 and pH 13, whereas they disassemble at pH 3 and pH 11. Further disassembly can be achieved at elevated temperatures at pH 1 and pH 13. Thus, we were able to prepare functionalized nanoparticles that can be assembled/disassembled in seven alternating regimes, simply controlled by pH and temperature.

Dual pH-Induced Reversible Self-Assembly of Gold Nanoparticles by Surface Functionalization with Zwitterionic Ligands.

The dual pH-induced reversible self-assembly (PIRSA) of Au-nanoparticles (Au NPs) is reported, based on their decoration with the self-complementary guanidiniocarbonyl pyrrole carboxylate zwitterion (GCPZ). The assembly of such functionalized Au NPs is found at neutral pH, based on supramolecular pairing of the GCPZ groups. The resulting self-assembled system can be switched back to the disassembled state by addition of base or acid. Two predominant effects that contribute to the dual-PIRSA of Au NPs are identified, namely the ionic hydrogen bonding between the GCPZ groups, but also a strong hydrophobic effect. The contribution of each interaction is depending on the concentration of GCPZ on NPs, which allows to control the self-assembly state over a wide range of different water/solvent ratios.

Application of Plasma Treatment in Preparation of Soybean Oil Factory Sludge Catalyst and Its Application in Selective Catalytic Oxidation (SCO) Denitration.

At present, the most commonly used denitration process is the selective catalytic reduction (SCR) method. However, in the SCR method, the service life of the catalyst is short, and the industrial operation cost is high. The selective catalytic oxidation absorption (SCO) method can be used in a low temperature environment, which greatly reduces energy consumption and cost. The C/N ratio of the sludge produced in the wastewater treatment process of the soybean oil plant used in this paper is 9.64, while the C/N ratio of the sludge produced by an urban sewage treatment plant is 10⁻20. This study shows that the smaller the C/N ratio, the better the denitration efficiency of the catalyst. Therefore, dried oil sludge is used as a catalyst carrier. The influence of different activation times, and LiOH concentrations, on catalyst activity were investigated in this paper. The denitration performance of catalysts prepared by different activation sequences was compared. The catalyst was characterized by Fourier Transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and scanning electron microscope (SEM). The experimental results showed that: (1) When the concentration of the LiOH solution used for activation is 15%, and the activation time is four hours, the denitration effect of the catalyst is the best; (2) the catalyst prepared by activation before plasma roasting has the best catalytic activity.

Study on the NO removal efficiency of the lignite pyrolysis coke catalyst by selective catalytic oxidation method.

Selective catalytic oxidation (SCO) method is commonly used in wet denitration technology; NO after the catalytic oxidation can be removed with SO2 together by wet method. Among the SCO denitration catalysts, pyrolysis coke is favored by the advantages of low cost and high catalytic activity. In this paper, SCO method combined with pyrolysis coke catalyst was used to remove NO from flue gas. The effects of different SCO operating conditions and different pyrolysis coke catalyst made under different process conditions were studied. Besides, the specific surface area of the catalyst and functional groups were analyzed with surface area analyzer and Beohm titration. The results are: (1) The optimum operating conditions of SCO is as follows: the reaction temperature is 150°C and the oxygen content is 6%. (2) The optimum pyrolysis coke catalyst preparation processes are as follows: the pyrolysis final temperature is 750°C, and the heating rate is 44°C / min. (3) The characterization analysis can be obtained: In the denitration reaction, the basic functional groups and the phenolic hydroxyl groups of the catalyst play a major role while the specific surface area not.

Light-Induced Reversible Self-Assembly of Gold Nanoparticles Surface-Immobilized with Coumarin Ligands.

A novel light-induced reversible self-assembly (LIRSA) system is based on the reversible photodimerization and photocleavage of coumarin groups on the surface of gold nanoparticles (AuNPs) in THF solution. Facilitated by coumarin groups, light irradiation at 365 nm triggers the stable assembly of monodisperse AuNPs; the resulting self-assembly system can be disassembled back to the disassembled state by a relatively short exposure to benign UV light. The reversible self-assembly cycle can be repeated 4 times. A specific concentration range of coumarin ligand and the THF solvent were identified to be the two predominant factors that contribute to the LIRSA of AuNPs. This is the first successful application of reversible photodimerization based on a coumarin derivative in the field of AuNP LIRSA. This LIRSA system may provide unique opportunities for the photoregulated synthesis of many adjustable nanostructures and devices.