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Phytopathogenic bacteria are a major cause of crop mortality and yield reduction, especially in field cultivation. The lack of effective chemistry agri-bactericides is responsible for challenging field prevention and treatment, prompting the development of long-lasting solutions to prevent, reduce, or manage some of the most devastating plant diseases facing modern agriculture today and in the future. Therefore, there is an urgent need to find lead drugs preventing and treating phytopathogenic bacterial infection. Drug repurposing, a strategy used to identify novel uses for existing approved drugs outside of their original indication, takes less time and investment than Traditional RD Strategies in the process of drug development. Based on this method, we conduct a screen of 700 chemically diverse and potentially safe drugs against Xanthomonas oryzae PV. oryzae ACCC 11602 (Xoo), Xanthomonas axonopodis PV. citri (Xac), and Pectobacterium atrosepticum ACCC 19901 (Pa). Furthermore, the structure-activity relationship and structural similarity analysis of active drugs classify potent agri-bactericides into 8 lead series: salicylanilides, cationic nitrogen-containing drugs, azole antifungals, N-containing group, hydroxyquinolines, piperazine, kinase inhibitor and miscellaneous groups. MIC values were evaluated as antibacterial activities in this study. Identifying highly active lead compounds from the screening of approved drugs and comparison with the currently applied plant pathogenic bactericide to validate the bactericidal activity of the best candidates and assess if selected molecules or scaffolds lead to develop new antibacterial agents in the future. In conclusion, this study provides a possibility for the development of potent and highly selective agri-bactericides leads.

The periosteum orchestrates the microenvironment of bone regeneration, including facilitating local neuro-vascularization and regulating immune responses. To mimic the role of natural periosteum for bone repair enhancement, we adopted the principle of biomimetic mineralization to delicately inlay amorphous cerium oxide within eggshell membranes (ESMs) for the first time. Cerium from cerium oxide possesses unique ability to switch its oxidation state from cerium III to cerium IV and vice versa, which provides itself promising potential for biomedical applications. ESMs are mineralized with cerium(III, IV) oxide and examined for their biocompatibility. Apart from serving as physical barriers, periosteum-like cerium(III, IV) oxide-mineralized ESMs are biocompatible and can actively regulate immune responses and facilitate local neuro-vascularization along with early-stage bone regeneration in a murine cranial defect model. During the healing process, cerium-inlayed biomimetic periosteum can boost early osteoclastic differentiation of macrophage lineage cells, which may be the dominant mediator of the local repair microenvironment. The present work provides novel insights into expanding the definition and function of a biomimetic periosteum to boost early-stage bone repair and optimize long-term repair with robust neuro-vascularization. This new treatment strategy which employs multifunctional bone-and-periosteum-mimicking systems creates a highly concerted microenvironment to expedite bone regeneration.

Morphology-controlled electrocatalysts with the ability of CO2 adsorption/activation, mass transfer, high stability and porosity are much desired in electrochemical CO2 reduction reaction (CO2RR). Here, three kinds of multi-dimensional nanostructures (i.e., hollow sphere, nanosheets and nanofibers) have been successfully produced through the modulation of porphyrin-based covalent organic frameworks (COFs) with various modulators. The obtained nanostructures with high-stability, large surface-area, and single metal sites enable efficient CO2RR into CH4. Notably, they all exhibit higher FECH4 (hollow sphere, 68.2%; nanosheet, 64.2% and nanofiber, 71.0%, -0.9 V) than COF-366-Cu (43.0%, -0.9 V) after morphology control. Noteworthy, the FECH4 of COF-366-Cu (HS) keeps higher than 52.4% over a wide potential range from -0.9 V to -1.1 V and the achieved FECH4+C2H4 (82.8%, -0.9 V) is superior to most of reported COFs and copper-based electrocatalysts. This work paves a new way in the exploration of COF-based multi-dimensional nanostructures applicable in efficient CO2RR to CH4.

A series of metalloporphyrin based electrocatalysts with efficient CO2-to-CH4 electroreduction properties have been facilely synthesized and relative direct-bonding interactions have been intensively studied.

Purposefully designing the well-defined catalysts for the selective electroreduction of CO2 to C2 H4 is an extremely important but challenging work. In this work, three crystalline trinuclear copper clusters (Cu3 -X, X=Cl- , Br- , NO3- ) have been designed, containing three active Cu sites with the identical coordination environment and appropriate spatial distance, delivering high selectivity for the electrocatalytic reduction of CO2 to C2 H4 . The highest faradaic efficiency of Cu3 -X for CO2 -to-C2 H4 conversion can be adjusted from 31.90 % to 55.01 % by simply replacing the counter anions (NO3- , Cl- , Br- ). The DFT calculation results verify that Cu3 -X can facilitate the C-C coupling of identical *CHO intermediates, subsequently forming molecular symmetrical C2 H4 product. This work provides an important molecular model system and a new design perspective for electroreduction of CO2 to C2 products with symmetrical molecular structure.

To evaluate in a laboratory setting, the impact of three designs of endodontic access cavities on dentine removal and effectiveness of canal instrumentation in extracted maxillary first molars using micro-computed tomography (micro-CT).A total of 30 extracted intact maxillary first molars were selected and scanned by micro-CT with a voxel size of 24 µm and randomly distributed into three groups: the traditional endodontic cavity (TEC) group, the conservative endodontic cavity (CEC) group and the guided endodontic cavity (GEC) group. The pulp chambers of teeth in the groups were accessed accordingly. After root canal preparation, the teeth were rescanned. The volume of dentine removed after canal preparation, the noninstrumented canal areas, canal transportation and centring ratio were analysed. Data were analysed statistically using one-way analysis of variance. Tukey's post hoc test was used for multiple comparisons. The significance level was set at p .05.The total volume of dentine removed was significantly greater in the TEC group after root canal preparation (p .05). No significant differences in the volume of dentine removed occurred between the CEC and GEC groups (p .05). The volume of dentine removed in the crown, pericervical dentine and coronal third of the canal was significantly lower in CEC and GEC groups when compared to that in the TEC group (p .05), no difference was observed in the middle third of the canal and apical third of the canal amongst the three groups (p .05). There was no significant difference in noninstrumented canal area, canal transportation and centring ratio amongst the TEC, CEC and GEC groups (p .05).In extracted maxillary molars tested in a laboratory setting, CEC and GEC preserved more tooth tissue in the crown, pericervical dentine and coronal third of the canal compared with TEC after root canal preparation. The design of the endodontic access cavity did not impact on the effectiveness of canal instrumentation in terms of noninstrumented canal area, canal transportation and centring ratio.

The exploration of novel systems for the electrochemical CO2 reduction reaction (CO2 RR) for the production of hydrocarbons like CH4 remains a giant challenge. Well-designed electrocatalysts with advantages like proton generation/transferring and intermediate-fixating for efficient CO2 RR are much preferred yet largely unexplored. In this work, a kind of Cu-porphyrin-based large-scale (≈1.5 μm) and ultrathin nanosheet (≈5 nm) has been successfully applied in electrochemical CO2 RR. It exhibits a superior FE CH 4 of 70 % with a high current density (-183.0 mA cm-2 ) at -1.6 V under rarely reported neutral conditions and maintains FE CH 4 >51 % over a wide potential range (-1.5 to -1.7 V) in a flow cell. The high performance can be attributed to the construction of numerous hydrogen-bonding networks through the integration of diaminotriazine with Cu-porphyrin, which is beneficial for proton migration and intermediate stabilization, as supported by DFT calculations. This work paves a new way in exploring hydrogen-bonding-based materials as efficient CO2 RR catalysts.

Tooth biomineralization is a dynamic and complicated process influenced by local and systemic factors. Abnormal mineralization in teeth occurs when factors related to physiologic mineralization are altered during tooth formation and after tooth maturation, resulting in microscopic and macroscopic manifestations. The present Review provides timely information on the mechanisms and structural alterations of different forms of pathological tooth mineralization. A comprehensive study of these alterations benefits diagnosis and biomimetic treatment of abnormal mineralization in patients.

Porous heterostructured electrocatalysts with multifunctionality and synergistic effect have much benefit for efficient electrocatalytic CO

Multidimensional fabrication of metal-organic frameworks (MOFs) into multilevel channel integrated devices are in high demanded for Li-S separators. Such separators have advantages in pore-engineering that might fulfill requirements such as intercepting the diffusing polysulfides and improving the Li+ /electrolyte transfer in Li-S batteries. However, most reported works focus on the roles of MOFs as ionic sieves for polysulfides while offering limited investigation on the tuning of Li+ transfer across the separators. A photoinduced heat-assisted processing strategy is proposed to fabricate MOFs into multidimensional devices (e.g., hollow/Janus fibers, double-or triple-layer membranes). For the first time, a triple-layer separator with stepped-channels has been designed and demonstrated as a powerful separator with outstanding specific capacity (1365.0 mAh g-1 ) and cycling performance (0.03 % fading per cycle from 100th to 700th cycle), which is superior to single/double-layer and commercial separators. The findings may expedite the development of MOF-based membranes and extend the scope of MOFs in energy-storage technologies.

Summary γ-butyrolactone (γ-BL), serving as the monomer of biocompatible and recyclable poly(γ-butyrolactone) plastic, faces a giant challenge in ring-opening polymerization (ROP) due to its low strain energy. The ROP of γ-BL is generally achieved under harsh conditions (e.g., high-pressure or gas-protected atmosphere) and is mostly based on homogeneous systems. Here, we synthesize a series of lanthanum metal-organic framework-based porous nanospheres and successfully apply them as heterogeneous catalysts in efficient ROP of γ-BL under mild conditions. Specifically, NNU-mIM-3 presents a yield of 24.6% with low polydispersity distribution centered at 3.6 kDa and the obtained PγBL can be completely and quantitatively recycled into monomers by simple heat treatment. Besides, the ROP catalysis systems have been intensively explored with various imine-based additives, proven to exhibit largely improved performance with PγBL yield of ~50% and Mw of ~8 kDa. This work paves a new way to explore novel heterogeneous catalysts in producing biocompatible and degradable plastics.

Polyoxometalates (POMs), possessing multiple-electron redox ability, controllable size, and precise structure, hold much promise to be applied as anode materials in lithium-ion batteries (LIBs). Ho...

Electrochemical CO2 reduction reaction (CO2RR) to formate is economically viable considering the energy input and market value. Through learning nature, a series of chloroplast-like porous bismuth-based core–shell (CPBC) materials have been designed. In these materials, the porous carbon can enrich and transfer CO2 to the core–shell Bi@Bi2O3 in CO2 reduction process, during which Bi2O3 layer can be transformed into activated metastable layer to efficiently convert CO2 into formate and Bi can provide abundant electrons. Based on this, superior performances for most of important parameters in CO2RR can be achieved and best of them, CPBC-1 presents remarkable Faradaic efficiency (FEformate > 94%) over a wide potential range (−0.65 to −1.0 V) with high catalysis durability (>72 h). Noteworthy, its maximum energy efficiency is as high as 76.7% at −0.7 V, the highest one in reported bismuth-based materials. This work opens novel perspectives in designing nature-inspired CO2RR electrocatalysts.

Strategies that enable simultaneous morphology-tuning and electroreduction performance boosting are much desired for the exploration of covalent organic frameworks in efficient CO

Purposefully designing the well-defined catalysts for the selective electroreduction of CO

Efficient conversion of carbon dioxide (CO2) into value-added products is essential for clean energy research. Design of stable, selective, and powerful electrocatalysts for CO2 reduction reaction (CO2RR) is highly desirable yet largely unmet. In this work, a series of metalloporphyrin-tetrathiafulvalene based covalent organic frameworks (M-TTCOFs) are designed. Tetrathiafulvalene, serving as electron donator or carrier, can construct an oriented electron transmission pathway with metalloporphyrin. Thus-obtained M-TTCOFs can serve as electrocatalysts with high FECO (91.3%, −0.7 V) and possess high cycling stability (>40 h). In addition, after exfoliation, the FECO value of Co-TTCOF nanosheets (~5 nm) is higher than 90% in a wide potential range from −0.6 to −0.9 V and the maximum FECO can reach up to almost 100% (99.7%, −0.8 V). The electrocatalytic CO2RR mechanisms are discussed and revealed by density functional theory calculations. This work paves a new way in exploring porous crystalline materials in electrocatalytic CO2RR., The study of covalent organic frameworks (COFs) in electrocatalytic CO2 reduction reaction (CO2RR) has drawn much attention. Here the authors show a series of tetrathiafulvalene based COFs designed and exfoliated into nanosheets which exhibit high electrocatalytic CO2RR performance.

Microplastics are a worldwide problem that poses a giant threat to organisms in the ecosystem and even to human health. The removal of microplastics is a severe challenge that needs to be solved urgently. Herein, a series of zirconium metal–organic framework-based foam materials with interpenetrated pores, high MOF uniformity and excellent durability have been successfully fabricated and applied in simulated microplastics removal in water or seawater conditions. They can be applied to various types and concentrations of microplastics suspensions. It is worth noting that the best of them, UiO-66-OH@MF-3, can efficiently remove microplastics with an efficiency of up to 95.5 ± 1.2% and can maintain high performance in recycling and large-quantity filtration experiments. Besides, we proposed an automatic filtration system powered by sunlight and accomplished it on the lab-scale. The high performances of these foam materials combined with the new concept of automatic filtration systems might shed some light on the development of novel techniques for microplastics removal.

Summary The activation of CO2 on the electrocatalyst surface is regarded as the rate-determining step in electrocatalytic CO2 reduction (ECR), and it is therefore highly important to find out its adsorption and activation mechanism. Herein, we develop the OH–-coordinated metal-organic framework (NNU-15) to simulate the surface state of catalyst in alkaline environment of ECR and then further explore its activation mechanism to CO2. NNU-15 shows high faradic efficiency for CO (FECO) reaching up to 99.2% at −0.6 V versus RHE along with long-term stability (110 h) and surpassing 96% over a wide potential range from −0.6 to −0.9 V. In the ECR process, single-crystal to single-crystal transformation between NNU-15 and NNU-15-CO2 demonstrates that coordinated OH– can activate the CO2 into HCO3–, which will chelate to the metal center. Theoretical calculations validate that both O-adsorbed and C-adsorbed initial geometries are inclined to result in the formation of HCO3– during the ECR process.

Polyester plastics such as poly(ethylene terephthalate) (PET) are utilized commonly in everyday life, yet only a small portion of these plastics are recycled, and typically, the recycling procedure...

The design of selective and efficient covalent organic frameworks (COFs) based electrocatalysts with tunable morphology for efficient CO2 reduction reaction (CO2RR) to CH4 is highly desirable. Here, two kinds of anthraquinone-based COFs (i.e., AAn-COF and OH-AAn-COF) with tunable 1D superstructures (e.g., nanofibers (NF) and hollow tubes (HT)) have been produced via Schiff-base condensation reaction. Interestingly, a rarely reported nanosheet-based self-template mechanism and a nanosheet-crimping mechanism have been demonstrated for the production of COF-based nanofibers and hollow tubes, respectively. Besides, the obtained COF-based superstructures can be post-modified with transition metals for efficient CO2RR. Specifically, AAn-COF-Cu (NF) and OH-AAn-COF-Cu (HT) exhibit superior faradaic-efficiency with CH4 (FECH4) of 77% (−128.1 mA cm−2, −0.9 V) and 61% (−99.5 mA cm−2, −1.0 V) in a flow-cell, respectively. Noteworthy, the achieved FECH4 of AAn-COF-Cu (NF) (77%) the is highest one among reported crystalline COFs. This work provides a general methodology in exploring morphology-controlled COFs for electrocatalytic CO2RR.

This study investigated the probable mechanisms of endoplasmic reticulum (ER) stress involved in periodontitis in vitro and in vivo. We isolated periodontal ligament stem cells from periodontitis patients and healthy controls (P-PDLSCs and H-PDLSCs). To further simulate the periodontal microenvironment in patients, lipopolysaccharide (LPS) was used to treat H-PDLSCs. The results showed that periodontitis-related inflammation gave rise to the upregulated expression levels of ER stress representative genes including GRP78, PERK, ATF4, and CHOP. In contrast, the treatment of 4-phenyl butyric acid (4-PBA) remarkably suppressed ER stress and supported cell viability. The increased secretion of proinflammatory factors like TNF-α, IL-1β, and IL-6 and the activation of NF-κB pathway were also attenuated by 4-PBA treatment. Moreover, 4-PBA treatment restored the impaired osteogenic differentiation ability of PDLSCs, as demonstrated by the upregulated expression levels of Runx2 and OCN as well as the enhanced Alizarin red staining. Local administration of 4-PBA could rescue alveolar bone resorption of LPS-induced periodontitis rats. Thus, our findings suggested ER stress might act as a promising therapeutic target against periodontitis.

Identification of the real catalytic site in CO2 reduction reaction (CO2RR) is critical for the rational design of catalysts and the understanding of reactive mechanisms. In this study, the catalytic activity of pyridine-containing materials was for the first time structurally demonstrated in CO2RR by crystalline supramolecular coordination compounds model system. The system consists of three stable supramolecular coordination compounds (Ni-TPYP, Ni-TPYP-1 and Ni-TPP) with different numbers (4, 2 and 0) of active pyridine groups (i.e. uncoordinated pyridine nitrogen atoms). The electrocatalytic test results show that with the decrease of the number of active pyridine groups, the CO2RR performance is gradually reduced, mainly showing the reduction of highest FECO (99.8%, 83.7% and 25.6%, respectively). The crystallographic, experimental and theoretical evidences prove that the CO2RR activity is more likely derived from uncoordinated pyridine nitrogen than the electrocatalytic inert metal nickel in porphyrin center. This work serves as an important case study for the identification of electrocatalytic activity of pyridine-containing materials in CO2RR by simple supramolecular model system., The catalytic activity of pyridine-containing materials was for the first time structurally demonstrated in CO2 reduction reaction by supramolecular and coordination compounds structure model system including Ni-TPP, Ni-TPYP and Ni-TPYP-1.

Metal–organic framework (MOF) based mixed matrix membranes (MMMs) have received significant attention in applications such as gas separation, sensing, and energy storage. However, the mass production of MOF‐based MMMs with retained porosity remains a longstanding challenge. Herein, an in situ heat‐assisted solvent‐evaporation method is described to facilely produce MOF‐based MMMs. This method can be extended into various MOFs and polymers with minimum reaction time of 5 min. Thus‐obtained MMMs with high uniformity, excellent robustness, well‐tuned loading, and thickness can be massively produced in industrial‐level efficiency (≈4 m in a batch experiment). Furthermore, they can be readily applied as powerful separators for Li–S cell with high specific capacity (1163.7 mAh g−1) and a capacity retention of 500.7 mAh g−1 after 700 cycles at 0.5 C (0.08% fading per cycle). This work may overcome the longstanding challenge of processing MOFs into MMMs and largely facilitate the industrialization process of MOFs., An in situ heat‐assisted solvent‐evaporation method is developed to facilely fabricate porous and robust metal–organic framework‐based mixed matrix membranes (MMMs). The obtained MMMs with high uniformity, excellent robustness, well‐tuned loading, and thickness can be massively produced (≈4 m in a batch experiment in lab scale) and exhibit high performances in separators for Li–S battery.