Publisher Correction: Cleavable comonomers enable degradable, recyclable thermoset plastics.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Cleavable comonomers enable degradable, recyclable thermoset plastics.

Thermosets-polymeric materials that adopt a permanent shape upon curing-have a key role in the modern plastics and rubber industries, comprising about 20 per cent of polymeric materials manufactured today, with a worldwide annual production of about 65 million tons1,2. The high density of crosslinks that gives thermosets their useful properties (for example, chemical and thermal resistance and tensile strength) comes at the expense of degradability and recyclability. Here, using the industrial thermoset polydicyclopentadiene as a model system, we show that when a small number of cleavable bonds are selectively installed within the strands of thermosets using a comonomer additive in otherwise traditional curing workflows, the resulting materials can display the same mechanical properties as the native material, but they can undergo triggered, mild degradation to yield soluble, recyclable products of controlled size and functionality. By contrast, installation of cleavable crosslinks, even at much higher loadings, does not produce degradable materials. These findings reveal that optimization of the cleavable bond location can be used as a design principle to achieve controlled thermoset degradation. Moreover, we introduce a class of recyclable thermosets poised for rapid deployment.

Mechanistic study of NUPR1 in bladder cancer development through transcriptional regulation of CCR2.

Nuclear protein-1 (NUPR1) (also known as p8) is one of the genes associated with transcription factors that participate in various aspects of cancer initiation and development. However, the molecular mechanisms of NUPR1 in bladder cancer (BLCA) remain unclear. We conducted an analysis of the correlation between NUPR1 expression and related genes using the Gene Expression Omnibus (GEO) online database. We employed lentivirus-mediated small interfering RNA (siRNA) to knockdown the expression of NUPR1 in two human BLCA cell lines. In vitro experiments were conducted to validate the impact of NUPR1 interference on BLCA and the influence of NUPR1 on the transcription of chemokine receptor-2 (CCR2). Furthermore, transcription factors for CCR2 were predicted using the PROMO database. Co-immunoprecipitation (Co-IP) and immunofluorescence double staining were used to detect the binding between NUPR1 and CCAAT/enhancer binding protein γ (CEBPG). In vivo and in vitro experiments were conducted to validate that NUPR1 regulates CCR2 transcription through CEBPG. In vitro experiments indicate that the suppression of NUPR1 inhibited BLCA growth. Analysis of the GEO database revealed a positive correlation between the expression of NUPR1 and CCR2. Luciferase experiments confirmed that NUPR1 influences the transcription of CCR2. Online data indicates that CEBPG is a transcription factor for CCR2. Co-IP and immunofluorescence double staining confirmed binding between NUPR1 and CEBPG. Luciferase assays and chromatin immunoprecipitation (ChIP) demonstrate that CEBPG regulates the transcription of CCR2. Additionally, rescue experiments at the cellular level and animal experiments validated the aforementioned mechanism. NUPR1 promotes a promotional role in BLCA, and interference with NUPR1 can inhibit the proliferation and invasive abilities of BLCA. There was a correlation between the expressions of NUPR1 and CCR2, and NUPR1 binds with CEBPG in the cell nucleus. Transcriptional regulation of CCR2 by NUPR1 may be achieved through the involvement of CEBPG.

Dielectric Ceramics Database Automatically Constructed by Data Mining in the Literature.

Vast published dielectric ceramics literature is a natural database for big-data analysis, discovering structure-property relationships, and property prediction. We constructed a data-mining pipeline based on natural language processing (NLP) to extract property information from about 12,900 published dielectric ceramics articles and normalized more than 20 properties. The micro-F1 scores for sentence classification, named entities recognition, relation extraction (related), and relation extraction (same), are 91.6, 82.4, 91.4, and 88.3%, respectively. We demonstrated the distribution of some essential properties according to the publication years to reveal the tendency. In order to test the reliability of the data extraction, we trained an XGBoost model to predict the dielectric constant and used the SHAP module to interpret the contribution of each feature in order to identify some of the factors that determine the dielectric properties. The result shows that including Q × f in the model can increase the dielectric constant prediction accuracy. Our work can give some hints to experimentalists on their way to improve the performances of cutting-edge materials.

Construction of Ni3S4@ZIS@C3N5 photocatalyst with type II and Z-type heterojunctions by self-assembly for efficient photocatalytic hydrogen evolution.

A novel ternary photocatalyst Ni3S4@ZIS@C3N5 with type II and Z-type heterojunctions was synthesized for the first time by hydrothermal and electrostatic self-assembly methods, effectively avoiding the thermal decomposition of C3N5 during the synthesis of the complex. The best ternary catalyst Ni3S4@ZIS@C3N5 is capable of achieving an optimal hydrogen evolution rate of 9750 mmol g-1 h-1, which is approximately 10.89 times as high as that of C3N5, indicating that the complex effectively enhanced the photocatalytic properties of the monomer. The coexistence of two types of heterojunctions in the complex effectively enhances photocatalytic performance, in which the monomer ZIS constructs type II scheme with Ni3S4 and Z-type scheme with C3N5, respectively. The two heterojunctions complement each other and jointly promote the rapid electron transfer from Ni3S4 and C3N5 to the ZIS surface. In conclusion, the cooperation of the two heterojunctions efficiently facilitates the migration of photogenerated carriers, thus enhancing the photocatalytic hydrogen generation performance of Ni3S4@ZIS@C3N5.

Clip Chemistry: Diverse (Bio)(macro)molecular and Material Function through Breaking Covalent Bonds.

In the two decades since the introduction of the "click chemistry" concept, the toolbox of "click reactions" has continually expanded, enabling chemists, materials scientists, and biologists to rapidly and selectively build complexity for their applications of interest. Similarly, selective and efficient covalent bond breaking reactions have provided and will continue to provide transformative advances. Here, we review key examples and applications of efficient, selective covalent bond cleavage reactions, which we refer to herein as "clip reactions." The strategic application of clip reactions offers opportunities to tailor the compositions and structures of complex (bio)(macro)molecular systems with exquisite control. Working in concert, click chemistry and clip chemistry offer scientists and engineers powerful methods to address next-generation challenges across the chemical sciences.

Improving the ability of straw biochar to remediate Cd contaminated soil: KOH enhanced the modification of K3PO4 and urea on biochar.

In recent years, the improvement of soil cadmium (Cd) contamination remediation effect of biochar by modification has received wide attention. However, the effect of combined modification on biochar performance in soil Cd contamination remediation and the mechanism are still unclear. In this study, cotton straw biochar and maize straw biochar were co-modified by KOH (0, 3, 5 mol L-1), K3PO4, and urea. Then, two modified biochars with high Cd adsorption capacity were selected to test the soil Cd contamination remediation effect through a pot experiment. The results showed that the combined modification by using KOH, K3PO4, and urea significantly increased the specific surface area and nitrogen (N) and phosphorus (P) contents of biochar, providing more adsorption sites for Cd. Among the modified biochar, the cotton straw biochar modified with KOH (3 mol L-1), K3PO4, and urea (m3-CSB) had the highest adsorption capacity (111.25 mg g-1), which was 7.86 times that of cotton straw biochar (CSB). The m3-CSB for adsorption isotherm and kinetics of Cd conformed to the Langmuir model and Pseudo-second-order kinetic equation, respectively. In the pot experiment, under different exogenous Cd levels (0 (Cd0), 4 (Cd4), and 8 (Cd8) mg kg-1), m3-CSB treatment decreased soil available Cd content the most (51.68%-63.4%) compared with other biochar treatments. Besides, m3-CSB treatment significantly promoted the transformation of acid-soluble Cd to reducible, oxidizable, and residual Cd, reducing the bioavailability of Cd. At the Cd4 level, the application of m3-CSB significantly reduced cotton Cd uptake compared to CK, and the maximum reduction of Cd content in cotton fibers was as high as 81.95%. Therefore, cotton straw biochar modified with KOH (3 mol L-1), K3PO4, and urea has great potential in the remediation of soil Cd contamination.

Robust and Wide Temperature-Range Zinc Metal Batteries with Unique Electrolyte and Substrate Design.

Rechargeable zinc metal batteries are promising for large-scale energy storage. However, their practical application is limited by harsh issues such as uncontrollable dendrite growth, low Coulombic efficiency, and poor temperature tolerance. Herein, a unique design strategy using γ-valerolactone-based electrolyte and nanocarbon-coated aluminum substrate was reported to solve the above problems. The electrolyte with extremely low freezing point and high thermal stability enables the symmetric cells with long cycle life over a wide temperature range (-50 °C to 80 °C) due to its ability to regulate zinc nucleation and preferential epitaxial growth. Besides, the nanocarbon-coated aluminum substrate can also promote a higher Coulombic efficiency over a wide temperature range in contrast to the low Coulombic efficiency of copper substrates with significant irreversible alloying reactions because this unique substrate with excellent chemical stabilization can homogenize the interfacial electron/ion distribution. The optimized zinc metal capacitors can operate stably under various temperature conditions (2000 cycles at 30 °C with 66 % depth of discharge and 1200 cycles at 80 °C with 50 % depth of discharge). This unique electrolyte and substrate design strategy achieves a robust zinc metal battery over a wide temperature range.

Waste Cabbage-Integrated Nutritional Superabsorbent Polymers for Water Retention and Absorption Applications.

To alleviate soil impoverishment and water shortage in desert areas, as well as to reduce the impact of waste cabbage on the environment and human health, we used waste cabbage as a substrate, 2-acrylamide-2-methyl-1-propane sulfonic acid (AMPS) and acrylic acid (AA) as polymerization units, and NH4Cl and KNO3 as nutriment to obtain two waste cabbage-superabsorbent polymers (CB-SAPNH4Cl and CB-SAPKNO3) by the one-pot method. The chemical structure, thermal stability, and morphology of the polymers were investigated by Fourier-transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), and scanning electron microscope (SEM). Meanwhile, the water retention, water absorption, and salt resistance were compared with the purchased polymers. The results showed that the nutriment was successfully encapsulated inside the polymer, and CB-SAPNH4Cl and CB-SAPKNO3 at 1% nutrient concentration showed excellent water retention properties, salt resistance, and water absorption performance of 1546 and 1131 g/g (distilled water), 306 and 277 g/g (tap water), and 116 and 91 g/g (0.9% NaCl solution). Therefore, they are highly promising materials for the application.

Synthesis of Superabsorbent Polymer Hydrogels with Rapid Swelling: Effect of Reaction Medium Dosage and Polyvinylpyrrolidone on Water Absorption Rate.

A superabsorbent polymer (SAP) was synthesized by solution polymerization. The influence of synthesis technology was studied and optimized, and FTIR, SEM, and TGA were used to characterize the structure and morphology of the material. Under the optimal synthesis conditions, the water absorption of the material can achieve about 80% of the saturation value in the first 20 min, and the material absorbs distilled water up to 2013 g/g. The SAP also has remarkable water retention and reswelling capability. The excellent performance makes it have a promising application in agriculture. In addition, the results show that the dosage of the reaction medium is a major factor for performance. Under the condition of the optimum value of other factors, the influence of the dosage of the reaction medium on water absorption can reach about 1000 g in distilled water.

DO-SRS imaging of metabolic dynamics in aging Drosophila.

Emerging studies have shown that lipid metabolism plays an important role in aging. High resolution in situ imaging of lipid metabolic dynamics inside cells and tissues affords a novel and potent approach for understanding many biological processes such as aging. Here we established a new optical imaging platform that combines D2O-probed stimulated Raman scattering (DO-SRS) imaging microscopy and a Drosophila model to directly visualize metabolic activities in situ during aging. The sub-cellular spatial distribution of de novo lipogenesis in the fat body was quantitatively imaged and examined. We discovered a dramatic decrease in lipid turnover in 35-day-old flies. Decreases in protein turnover occurred earlier than lipids (25-day vs. 35-day), and there are many proteins localized on the cell and lipid droplet membrane. This suggests that protein metabolism may act as a prerequisite for lipid metabolism during aging. This alteration of maintenance of protein turnover indicates disrupted lipid metabolism. We further found a significantly higher lipid turnover rate in large LDs, indicating more active metabolism in large LDs, suggesting that large and small LDs play different roles in metabolism to maintain cellular homeostasis. This is the first study that directly visualizes spatiotemporal alterations of lipid (and protein) metabolism in Drosophila during the aging process. Our study not only demonstrates a new imaging platform for studying lipid metabolism, but also unravels the important interconnections between lipid metabolism and aging.

PolyMOF Nanoparticles: Dual Roles of a Multivalent polyMOF Ligand in Size Control and Surface Functionalization.

Metal-organic framework nanoparticles (MOF NPs) have emerged as an important class of materials that display significantly enhanced performance in many applications compared to bulk MOF materials; their synthesis, however, commonly involves a tedious sequence that controls particle size and surface properties in separate steps. Now, a simple strategy to access functional MOF NPs in one pot is reported that uses a polyMOF ligand possessing a polymer block for surface functionalization and a coordination block with tunable multivalency for size control. This strategy produces uniform polyMOF-5 NPs with sizes down to 20 nm, displaying exceptional structural and colloidal stability upon exposure to ambient conditions. A detailed time-dependent study revealed that the polyMOF NPs were formed following an aggregation-confined crystallization mechanism. Generality was demonstrated through the synthesis of well-defined polyUiO-66 NPs.

In Vivo Detoxification of Lipopolysaccharide by Antimicrobial Peptides.

Abundant lipopolysaccharide (LPS) can result in sepsis and septic shock, indicating a serious Gram-negative bacterial contamination. We have developed a novel strategy based on dendritic antimicrobial peptides that can detoxify LPS. The dendritic antimicrobial peptides bind to LPS at the surface of Gram-negative bacteria, killing the bacteria but removing the LPS from the cell wall of dead Gram-negative bacteria, hence detoxifying pathogenic bacteria in its host cells and effectively improving survival of animals infected with Pseudomonas aeruginosa. Our findings provide a way to detoxify bacterial contamination.

Thermoelectric properties of monolayer MSe2 (M = Zr, Hf): low lattice thermal conductivity and a promising figure of merit.

Monolayer transition-metal dichalcogenides (TMDCs) MX2 (M = Mo, W, Zr, Hf, etc; X = S, Se, Te) have become well-known in recent times for their promising applications in thermoelectrics and field effect transistors. In this work, we perform a systematic study on the thermoelectric properties of monolayer ZrSe2 and HfSe2 using first-principles calculations combined with Boltzmann transport equations. Our results point to a competitive thermoelectric figure of merit (close to 1 at optimal doping) in both monolayer ZrSe2 and HfSe2, which is markedly higher than previous explored monolayer TMDCs such as MoS2 and MoSe2. We also reveal that the higher figure of merits arise mainly from their low lattice thermal conductivity, and this is partly due to the strong coupling of acoustic modes with low frequency optical modes. It is found that the figure of merits can be better optimized in n-type than in p-type. In particular, the performance of HfSe2 is superior to ZrSe2 at a higher temperature. Our results suggest that monolayer ZrSe2 and HfSe2 with lower lattice thermal conductivity than usual monolayer TMDCs are promising candidates for thermoelectric applications.

Successful treatment of a severely injured victim from 8.12 Tianjin Port Explosion, China.

A male patient, 55 years old, was found from a container yard 65 h later following a chemical warehouse explosion in Tianjin, China on August 12, 2015. He was about 50 m away from the explosion center. He was subjected to compound multiple trauma, multi-viscera function damage, multiple fractures, hemothorax, traumatic wet lung, respiratory failure I, hypovolemic shock and impaired liver and kidney functions. After a series of successful treatments, he was rescued and recovered well.

Edaravone dexborneol attenuates oxidative stress in experimental subarachnoid hemorrhage via Keap1/Nrf2 signaling pathway.

Background: Subarachnoid hemorrhage (SAH) serves as a disease characterized by high incidence rate, which is exceedingly prevalent and severe. Presently, there is no unambiguous or efficacious intervention for the neurological impairment following SAH. Administering multi-targeted neuroprotective agents to reduce oxidative stress (OS) and neuroinflammation caused by early brain injury (EBI) has been demonstrated to improve neurological function and prognosis following SAH. Edaravone dexborneol (EDB), a novel multi targeted neuroprotective medication, combines four parts edaravone (EDA) with 1 part (+)-borneol in proportion. Clinical trials conducted in China have revealed during 2 days of acute ischemic stroke (AIS), early administration of EDB leads to improved therapeutic outcomes compared to treatment in EDA monotherapy. Currently, there is no clear evidence that EDB can effectively treat SAH, therefore, our study aims to investigate its potential therapeutic effects and mechanisms on EBI after SAH. Method: We used the intravascular threading method to establish a mouse model of SAH to explore whether EDA and EDB could produce anti-OS and anti-apoptosis effects. Behavioral assessment of mice was conducted using the balance beam experiment and the modified Garcia scoring system. Neuronal damage due to OS and Keap1/Nrf2 signaling pathway were detected through techniques of immunofluorescence, Western blotting, spectrophotometry. The group of EDA and EDB were injected intraperitoneally for 72 h after SAH. Results: The experiment results indicated that EDB lead to remarkably positive results by significantly enhancing neurological function, reducing blood-brain barrier (BBB) injury, and effectively inhibiting neuronal apoptosis after SAH. Further examination indicated EDB significantly reduced the expression of Keap1 and increased the expression of Nrf2, and it inhibited MDA, and enhanced SOD activity after SAH. These outcomes surpassed the effectiveness observed in EDA monotherapy. However, the application of ML385 reversed the anti-OS effects of EDB and EDA. Conclusion: Our experimental findings indicated that EDB could activate Keap1/Nrf2 signaling pathway to reduce OS damage, thereby protecting neurological function and enhancing behavioral abilities after SAH. These outcomes could facilitate the creation of new approaches for the clinical management of SAH.

Aloe-emodin from Sanhua Decoction inhibits neuroinflammation by regulating microglia polarization after subarachnoid hemorrhage.

ETHNOPHARMACOLOGICAL RELEVANCE: Subarachnoid hemorrhage (SAH) triggers a cascade of events that lead to early brain injury (EBI), which contributes to poor outcomes and appears within 3 days after SAH initiation. EBI involves multiple process including neuronal death, blood-brain barrier (BBB) injury and inflammation response. Microglia are cluster of immune cells originating in the brain which respond to SAH by changing their states and releasing inflammatory molecules through various signaling pathways. M0, M1, M2 are three states of microglia represent resting state, promoting inflammation state, and anti-inflammation state respectively, which can be modulated by pharmacological strategies. AIM OF THE STUDY: After identified potential active ingredients and targets of Sanhua Decoction (SHD) for SAH, we selected aloe-emodin (AE) as a potential ingredient modulating microglia activation states. MATERIALS AND METHODS: Molecular mechanisms, targets and pathways of SHD were reveal by network pharmacology technique. The effects of AE on SAH were evaluated in vivo by assessing neurological deficits, neuronal apoptosis and BBB integrity in a mouse SAH model. Furthermore, BV-2 cells were used to examine the effects of AE on microglial polarization. The influence of AE on microglia transformation was measured by Iba-1, TNF-α, CD68, Arg-1 and CD206 staining. The signal pathways of neuronal apoptosis and microglia polarization was measured by Western blot. RESULTS: Network pharmacology identified potential active ingredients and targets of SHD for SAH. And AE is one of the active ingredients. We also confirmed that AE via NF-κB and PKA/CREB pathway inhibited the microglia activation and promoted transformation from M1 phenotype to M2 at EBI stage after SAH. CONCLUSIONS: AE, as one ingredient of SHD, can alleviate the inflammatory response and protecting neurons from SAH-induced injury. AE has potential value for treating SAH-induced nerve injury and is expected to be applied in clinical practice.

Multi-molecular hyperspectral PRM-SRS microscopy.

Lipids play crucial roles in many biological processes. Mapping spatial distributions and examining the metabolic dynamics of different lipid subtypes in cells and tissues are critical to better understanding their roles in aging and diseases. Commonly used imaging methods (such as mass spectrometry-based, fluorescence labeling, conventional optical imaging) can disrupt the native environment of cells/tissues, have limited spatial or spectral resolution, or cannot distinguish different lipid subtypes. Here we present a hyperspectral imaging platform that integrates a Penalized Reference Matching algorithm with Stimulated Raman Scattering (PRM-SRS) microscopy. Using this platform, we visualize and identify high density lipoprotein particles in human kidney, a high cholesterol to phosphatidylethanolamine ratio inside granule cells of mouse hippocampus, and subcellular distributions of sphingosine and cardiolipin in human brain. Our PRM-SRS displays unique advantages of enhanced chemical specificity, subcellular resolution, and fast data processing in distinguishing lipid subtypes in different organs and species.

Effect of atomic anti-site disorder on the anisotropic magnetoresistance in Fe50Co50alloys.

In order to understand the anti-site disorder effect on the anisotropic magnetoresistance (AMR) of alloys,Fe50Co50alloys were studied in this work using the fully relativistic spin-polarized Korringa-Kohn-Rostoker method. The anti-site disorder was modeled by interchanging Fe and Co atoms and treated by the coherent potential approximation. It is found that the anti-site disorder broadens the spectral function and decreases the conductivity. Our work emphasizes that the absolute variations of resistivity under magnetic moment rotation are less affected by atomic disorder. The annealing procedure improves the AMR by reduction of the total resistivity. At the same time, we also find that the fourth-order term in the angular dependent resistivity becomes weaker when the disorder increases, resulting from increased scattering of the states around the band-crossing.

Research Progress of Polysaccharide-Based Natural Polymer Hydrogels in Water Purification.

The pollution and scarcity of freshwater resources are global problems that have a significant influence on human life. It is very important to remove harmful substances in the water to realize the recycling of water resources. Hydrogels have recently attracted attention due to their special three-dimensional network structure, large surface area, and pores, which show great potential for the removal of pollutants in water. In their preparation, natural polymers are one of the preferred materials because of their wide availability, low cost, and easy thermal degradation. However, when it is directly used for adsorption, its performance is unsatisfactory, so it usually needs to be modified in the preparation process. This paper reviews the modification and adsorption properties of polysaccharide-based natural polymer hydrogels, such as cellulose, chitosan, starch, and sodium alginate, and discusses the effects of their types and structures on performance and recent technological advances.