Tailoring the Hydrophobic Interface of Core-Shell HKUST-1@Cu2O Nanocomposites for Efficiently Selective CO2 Electroreduction.

The electrochemical reduction of carbon dioxide (CO2) to ethylene creates a carbon-neutral approach to converting carbon dioxide into intermittent renewable electricity. Exploring efficient electrocatalysts with potentially high ethylene selectivity is extremely desirable, but still challenging. In this report, a laboratory-designed catalyst HKUST-1@Cu2O/PTFE-1 is prepared, in which the high specific surface area of the composites with improved CO2 adsorption and the abundance of active sites contribute to the increased electrocatalytic activity. Furthermore, the hydrophobic interface constructed by the hydrophobic material polytetrafluoroethylene (PTFE) effectively inhibits the occurrence of hydrogen evolution reactions, providing a significant improvement in the efficiency of CO2 electroreduction. The distinctive structures result in the remarkable hydrocarbon fuels generation with high Faraday efficiency (FE) of 67.41%, particularly for ethylene with FE of 46.08% (-1.0 V vs RHE). The superior performance of the catalyst is verified by DFT calculation with lower Gibbs free energy of the intermediate interactions with improved proton migration and selectivity to emerge the polycarbon（C2+） product. In this work, a promising and effective strategy is presented to configure MOF-based materials with tailored hydrophobic interface, high adsorption selectivity and more exposed active sites for enhancing the efficiency of the electroreduction of CO2 to C2+ products with high added value.

Redox Molecular Junction Metal-Covalent Organic Frameworks for Light-assisted CO2 Energy Storage.

Visible-light sensitive and bi-functionally favored CO2 reduction (CRR)/evolution (CER) photocathode catalysts that can get rid of the utilization of ultraviolet light and improve sluggish kinetics is demanded to conquer the current technique-barrier of traditional Li-CO2 battery. Here, a kind of redox molecular junction sp2c metal-covalent organic framework (i.e. Cu3-BTDE-COF) has been prepared through the connection between Cu3 and BTDE and can serve as efficient photocathode catalyst in light-assisted Li-CO2 battery. Cu3-BTDE-COF with redox-ability, visible-light-adsorption region, electron-hole separation ability and endows the photocathode with excellent round-trip efficiency (95.2 %) and an ultralow voltage hysteresis (0.18 V), outperforming the Schiff base COFs (i.e. Cu3-BTDA-COF and Cu3-DT-COF) and majority of the reported photocathode catalysts. Combined theoretical calculations with characterizations, Cu3-BTDE-COF with the integration of Cu3 centers, thiazole and cyano groups possess strong CO2 adsorption/activation and Li+ interaction/diffusion ability to boost the CRR/CER kinetics and related battery property.

Repurposing Salicylamides to Combat Phytopathogenic Bacteria and Induce Plant Defense Responses.

Based on the research strategy of "drug repurposing", a series of derivatives and marketed drugs that containing salicylic acid skeleton were tested for their antibacterial activities against phytopathogens. Salicylic acid can not only regulate some important growth metabolism of plants, but also induce plant disease resistance. The bioassay results showed that the salicylamides exhibited excellent antibacterial activity. Especially, oxyclozanide showed the best antibacterial effect against Xanthomonas oryzae, Xanthomonas axonopodis pv. citri and Pectobacterium atroseptica with MICs of 0.78, 3.12 and 12.5 µg.mL-1, respectively. In vivo experiments with rice bacterial leaf blight had further demonstrated that oxyclozanide exhibited stronger antibacterial activity than the commercial bactericide, thiodiazole copper. Oxyclozanide could induce plant defense responses through the determination of salicylic acid content and the activities of defense-related enzymes including CAT, POD, and SOD in rice. The preliminarily antibacterial mechanism study indicated that oxyclozanide exhibited the antibacterial activity by disrupting cell integrity and reducing bacterial pathogenicity. Additionally, oxyclozanide could induce plant defense responses through the determination of salicylic acid content.

Effect of access cavities on the biomechanics of mandibular molars: a finite element analysis.

INTRODUCTION: This study aimed to predict the fracture resistance of a mandibular first molar (MFM) with diverse endodontic cavities using finite element analysis (FEA). METHODS: Five experimental finite element models representing a natural tooth (NT) and 4 endodontically treated MFMs were generated. Treated MFM models were with a traditional endodontic cavity (TEC) and minimally invasive endodontic (MIE) cavities, including guided endodontic cavity (GEC), contracted endodontic cavity (CEC) and truss endodontic cavity (TREC). Three loads were applied, simulating a maximum bite force of 600 N (N) vertically and a normal masticatory force of 225 N vertically and laterally. The distributions of von Mises (VM) stress and maximum VM stress were calculated. RESULTS: The maximum VM stresses of the NT model were the lowest under normal masticatory forces. In endodontically treated models, the distribution of VM stress in GEC model was the most similar to NT model. The maximum VM stresses of the GEC and CEC models under different forces were lower than those of TREC and TEC models. Under vertical loads, the maximum VM stresses of the TREC model were the highest, while under the lateral load, the maximum VM stress of the TEC model was the highest. CONCLUSION: The stress distribution of tooth with GEC was most like NT. Compared with TECs, GECs and CECs may better maintain fracture resistance, TRECs, however, may have a limited effect on maintenance of the tooth resistance.

Regulation of Redox Molecular Junctions in Covalent Organic Frameworks for H2 O2 Photosynthesis Coupled with Biomass Valorization.

H2 O2 photosynthesis coupled with biomass valorization can not only maximize the energy utilization but also realize the production of value-added products. Here, a series of COFs (i.e. Cu3 -BT-COF, Cu3 -pT-COF and TFP-BT-COF) with regulated redox molecular junctions have been prepared to study H2 O2 photosynthesis coupled with furfuryl alcohol (FFA) photo-oxidation to furoic acid (FA). The FA generation efficiency of Cu3 -BT-COF was found to be 575 mM g-1 (conversion ≈100 % and selectivity >99 %) and the H2 O2 production rate can reach up to 187 000 µM g-1 , which is much higher than Cu3 -pT-COF, TFP-BT-COF and its monomers. As shown by theoretical calculations, the covalent coupling of the Cu cluster and the thiazole group can promote charge transfer, substrate activation and FFA dehydrogenation, thus boosting both the kinetics of H2 O2 production and FFA photo-oxidation to increase the efficiency. This is the first report about COFs for H2 O2 photosynthesis coupled with biomass valorization, which might facilitate the exploration of porous-crystalline catalysts in this field.

Redox-Active Crystalline Coordination Catalyst for Hybrid Electrocatalytic Methanol Oxidation and CO2 Reduction.

Hybrid CO2 electroreduction (HCER) is recognized as an important strategy to improve the total value of redox products and energy conversion efficiency. In this work, a coordination catalyst model system (Ni8 -TET with active oxidation sites, Ni-TPP with active reduction sites and PCN-601 with redox-active sites) for HCER was established for the first time. Especially, PCN-601 can complete both anodic methanol oxidation and cathodic CO2 reduction with FEHCOOH and FECO over 90 %. The performance can be further improved with light irradiation (FE nearly 100 %). DFT calculations reveal that the transfer of electrons from NiII 8 clusters to metalloporphyrins under electric fields results in the raised oxidizability of Ni8 clusters and the raised reducibility of metalloporphyrin, which then improves the electrocatalytic performance. This work serves as a well-defined model system and puts forward a new design idea for establishing efficient catalysts for hybrid CO2 electroreduction.

Imparting CO2 Electroreduction Auxiliary for Integrated Morphology Tuning and Performance Boosting in a Porphyrin-based Covalent Organic Framework.

Strategies that enable simultaneous morphology-tuning and electroreduction performance boosting are much desired for the exploration of covalent organic frameworks in efficient CO2 electroreduction. Herein, a kind of functionalizing exfoliation agent has been selected to simultaneously modify and exfoliate bulk COFs into functional nanosheets and investigate their CO2 electroreduction performance. The obtained nanosheets (Cu-Tph-COF-Dct) with large-scale (≈1.0 µm) and ultrathin (≈3.8 nm) morphology enable a superior FECH4 (≈80 %) (almost doubly enhanced than bare COF) with large current-density (-220.0 mA cm-2 ) at -0.9 V. The boosted performance can be ascribed to the immobilized functionalizing exfoliation agent (Dct groups) with integrated amino and triazine groups that strengthen CO2 absorption/activation, stabilize intermediates and enrich the CO concentration around the Cu active sites as revealed by DFT calculations. The point-to-point functionalization strategy for modularly assembling Dct-functionalized COF catalyst for CO2 electroreduction will open up the attractive possibility of developing COFs as efficient CO2 RR electrocatalysts.

Light, Heat and Electricity Integrated Energy Conversion System: Photothermal-Assisted Co-Electrolysis of CO2 and Methanol.

Strategy that can design powerful photothermal-catalysts to achieve photothermal-effect assisted coupling-catalysis is much desired for the improvement of energy conversion efficiency and redox product value in CO2 electroreduction system. Herein, a kind of bifunctional viologen-containing covalent organic framework (Ni-2CBpy2+ -COF) has been prepared and successfully applied in photothermal-assisted co-electrolysis of CO2 and methanol. Specifically, the FECO (cathode) and FEHCOOH (anode) for Ni-2CBpy2+ -COF can reach up to ≈100 % at 1.9 V with ≈31.5 % saved overall electricity-consumption when the anodic oxygen evolution reaction (OER) is replaced by methanol oxidation. The superior performance could be attributed to the cyclic diquats in Ni-2CBpy2+ -COF that enhance the photothermal effect (ΔT=49.1 °C) to accelerate faster charge transfer between catalyst and immediate species as well as higher selectivity towards desired products as revealed by DFT calculations and characterizations.

Efficient Electron Transfer from Electron-Sponge Polyoxometalate to Single-Metal Site Metal-Organic Frameworks for Highly Selective Electroreduction of Carbon Dioxide.

In this work, by combining the superiority of polyoxometalates (POMs) and catalytic single-metal site Co of metalloporphyrin, a series of mixed-valence POM-based metal-organic frameworks (MOFs) composites is synthesized by a post-modification method. The electron-transfer property of POM@PCN-222(Co) composite is significantly enhanced owing to the directional electron-transfer from POM to single-metal site Co in PCN-222(Co). In particular, H-POM@PCN-222(Co) gives a high Faradaic efficiency of 96.2% for electroreduction of CO2 into CO and good stability over 10 h. DFT calculations confirm that the directional electron transfer, which accelerates the multi-electron transfer from the electrode to active single-metal site Co, enriches the electron density of the Co center, and ultimately reduces the energy of the rate-determining step, thus increasing the catalytic activity of CO2 reduction reaction (CO2 RR). This work therefore suggests some new insight for the design of efficient electrocatalysts for CO2 RR.

The effects of endodontic access cavity design on dentine removal and effectiveness of canal instrumentation in maxillary molars.

AIM: 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). METHODOLOGY: 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. RESULTS: 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). CONCLUSIONS: 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.

Predesign of Catalytically Active Sites via Stable Coordination Cluster Model System for Electroreduction of CO2 to Ethylene.

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.

Implanting Numerous Hydrogen-Bonding Networks in a Cu-Porphyrin-Based Nanosheet to Boost CH4 Selectivity in Neutral-Media CO2 Electroreduction.

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.

Stepped Channels Integrated Lithium-Sulfur Separator via Photoinduced Multidimensional Fabrication of Metal-Organic Frameworks.

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.

Neuroprotective Mechanisms of Melatonin in Hemorrhagic Stroke.

Hemorrhagic stroke which consists of subarachnoid hemorrhage and intracerebral hemorrhage is a dominant cause of death and disability worldwide. Although great efforts have been made, the physiological mechanisms of these diseases are not fully understood and effective pharmacological interventions are still lacking. Melatonin (N-acetyl-5-methoxytryptamine), a neurohormone produced by the pineal gland, is a broad-spectrum antioxidant and potent free radical scavenger. More importantly, there is extensive evidence demonstrating that melatonin confers neuroprotective effects in experimental models of hemorrhagic stroke. Multiple molecular mechanisms such as antioxidant, anti-apoptosis, and anti-inflammation, contribute to melatonin-mediated neuroprotection against brain injury after hemorrhagic stroke. This review article aims to summarize current knowledge regarding the beneficial effects of melatonin in experimental models of hemorrhagic stroke and explores the underlying mechanisms. We propose that melatonin is a promising neuroprotective candidate that is worthy of further evaluation for its potential therapeutic applications in hemorrhagic stroke.

Comparative Analysis of the Gelsemium Alkaloids Metabolism in Human, Pig, Goat, and Rat Liver Microsomes.

AIM: The aim of this study was to investigate the metabolism of Gelsemium elegans in human, pig, goat and rat liver microsomes and to elucidate the metabolic pathways and cleavage patterns of the Gelsemium alkaloids among different species. METHODS: A human, goat, pig and rat liver microparticles were incubated in vitro. After incubating at 37°C for 1 hour and centrifuging, the processed samples were detected by HPLC/Qq-TOFMS was used to detect alcohol extract of Gelsemium elegans and its metabolites. RESULTS: Forty-six natural products were characterized from alcohol extract of Gelsemium elegans and 13 metabolites were identified. These 13 metabolites belong to the gelsemine, koumine, gelsedine, humantenine, yohimbane, and sarpagine classes of alkaloids. The metabolic pathways included oxidation, demethylation and dehydrogenation. After preliminary identification, the metabolites detected in the four species were different. All 13 metabolites were detected in pig and rat microsomes, but no oxidative metabolites of Gelsedine-type alkaloids were detected in goat and human microsomes. CONCLUSION: In this study, Gelsemium elegans metabolic patterns in different species are clarified and the in vitro metabolism of Gelsemium elegans is investigated. It is of great significance for its clinical development and rational application.

Offspring nursing extends mother's longevity in a long-term maternal cared spider.

Females typically outlive males in animals, especially in species that provide long-term maternal care. However, life history theory predicts that investments in reproduction, such as lactation and offspring nursing, often shorten caretakers' longevity. Aiming to interpret this paradox, we selected the lactating jumping spider Toxeus magnus to investigate the effects of reproductive activities on longevity for two sexes. We found that: (1) although "milk" provisioning reduces female's longevity, mothers who cared for offspring (provisioned "milk" and nursing) lived the longest compared to virgins and those did not provide care; (2) copulation increased female's longevity but had no effects on males; and (3) the two sexes have comparable developmental duration, but the female adult's longevity was 2.1 times that of male's. This study suggests that the time requirement for offspring dispersal might act as a key selective force favoring females' adulthood extension, which ultimately generates the longer-lived females in maternal cared species.

LRIG1 dictates the chemo-sensitivity of temozolomide (TMZ) in U251 glioblastoma cells via down-regulation of EGFR/topoisomerase-2/Bcl-2.

In the current study, we aimed to understand the potential role of leucine-rich repeats and immunoglobulin-like domains 1 (LRIG1) in TMZ-resistance of U251 glioma cells. We established TMZ-resistant U251 clones (U251/TMZ cells), which expressed low level of LRIG1, but high levels of epidermal growth factor receptor (EGFR), topoisomerase-2 (Topo-2) and Bcl-2. Depletion of LRIG1 by the targeted RNA interference (RNAi) upregulated EGFR/Topo-2/Bcl-2 in U251 cells, and the cells were resistant to TMZ. Reversely, over-expression of LRIG1 in U251 cells downregulated EGFR/Topo-2/Bcl-2 expressions, and cells were hyper-sensitive to TMZ. Our data suggested EGFR-dependent mammalian target of rapamycin (mTOR) activation was important for Topo-2 and Bcl-2 expressions in U251/TMZ cells. The EGFR inhibitor and the mTOR inhibitor downregulated Topo-2/Bcl-2 expressions, both inhibitors also restored TMZ sensitivity in U251/TMZ cells. Finally, inhibition of Topo-2 or Bcl-2 by targeted RNAi(s) knockdown or by the corresponding inhibitor re-sensitized U251/TMZ cells to TMZ, indicating that both Topo-2 and Bcl-2 were important for TMZ resistance in the resistant U251 cells. Based on these results, we concluded that LRIG1 inhibits EGFR expression and the downstream signaling activation, interferes with Bcl-2/Topo-2 expressions and eventually sensitizes glioma cells to TMZ.

Intracerebral schwannoma mimicking parasagittal meningioma.

A 24-year-old female patient presented to the neurological department after a seizure that lasted for 10 minutes. Magnetic resonance imaging revealed a cystic and heterogeneously enhanced giant mass in the right frontal lobe mimicking parasagittal meningioma. Surgery via a single frontal craniotomy confirmed the tumor was attached to the falx cerebri and sagittal sinus. The histological diagnosis was schwannoma. Since total resection of the tumor, the patient was seizure free. Twelve months of follow-up revealed good outcome.

Electronic Tuning of CO2 Interaction by Oriented Coordination of N-Rich Auxiliary in Porphyrin Metal-Organic Frameworks for Light-Assisted CO2 Electroreduction.

The efficient CO2 electroreduction into high-value products largely relies on the CO2 adsorption/activation or electron-transfer of electrocatalysts, thus site-specific functionalization methods that enable boosted related interactions of electrocatalysts are much desired. Here, an oriented coordination strategy is reported to introduce N-rich auxiliary (i.e., hexamethylenetetramine, HMTA) into metalloporphyrin metal organic frameworks (MOFs) to synthesize a series of site-specific functionalized electrocatalysts (HMTA@MOF-545-M, M = Fe, Co, and Ni) and they are successfully applied in light-assisted CO2 electroreduction. Noteworthy, thus-obtained HMTA@MOF-545-Co presents approximately two times enhanced CO2 adsorption-enthalpy and electrochemical active surface-area with largely decreased impedance-value after modification, resulting in almost twice higher CO2 electroreduction performance than its unmodified counterpart. Besides, its CO2 electroreduction performance can be further improved under light-illumination and displays superior FECO (≈100%), high CO generation rate (≈5.11 mol m-2  h-1 at -1.1 V) and energy efficiency (≈70% at -0.7 V). Theoretical calculations verify that the oriented coordination of HMTA can increase the charge density of active sites, almost doubly enhance the CO2 adsorption energy, and largely reduce the energy barrier of rate determining step for the boosted performance improvement. This work might promote the development of modifiable porous crystalline electrocatalysts in high-efficiency CO2 electroreduction.

A Novel Two-Dimensional Liquid Chromatography Combined with Ultraviolet Detection Method for Quantitative Determination of Pyridoxal 5'-Phosphate, 4-Pyridoxine Acid and Pyridoxal in Animal Plasma.

Vitamin B6 is an indispensable micronutrient in organisms and is widely distributed in blood, tissues, and organs. Changes in the content and ratio of vitamin B6 can affect the entire physiological condition of the body, so it becomes particularly important to reveal the relationship between changes in its content and disease by monitoring vitamin B6 levels in the organism. In this study, a two-dimensional liquid chromatography-UV detector (2D-LC-UV) was used to establish a method for the simultaneous detection of PLP, PA, and PL for the first time. First, PLP, PA, and PL were extracted with plasma: 0.6 M TCA: ultrapure water = 1:2:3 (v/v/v) and then derivatized. Enrichment and preliminary separation were performed on a one-dimensional column and automatically entered into a two-dimensional column for further separation. This method exhibited good selectivity, and the correlation coefficients for the analyte calibration curves were >0.99. The detection limits for PLP, PA, and PL were 0.1, 0.2, and 4 nmol/L, respectively. The results showed that the system has high loading capacity, excellent resolution, and a good peak shape. This method is expected to provide applicability for the determination of PLP, PA, and PL in pharmacological, pharmaceutical, and clinical research.