Metal-free photoinduced generation and alkynylation of carbamoyl radicals: a facile synthesis of alkynyl amides.

A metal-free photoinduced alkynylation of carbamoyl radicals with hypervalent iodine(III) reagents for a facile synthesis of alkynyl amides is described. This protocol features good functional group tolerance and a broad substrate scope for direct synthesis of alkynyl amide derivatives in good to excellent yields under mild and redox-neutral reaction conditions. The synthetic application is demonstrated by the late-stage installation of alkynyl amides into natural products and active pharmaceutical relevant molecules. The mechanistic studies indicated the simultaneous existence of photoredox catalytic and direct photoexcited processes, and the quantum yields confirmed the occurrence of the radical chain propagation process.

Pretreatment pulmonary tumor necrosis is a promising prognostic imaging biomarker for first-line anti-PD-1/PD-L1 therapy in advanced lung squamous cell carcinoma: a multi-institutional, propensity score-matching cohort analysis.

Background: Tumor necrosis (TN) is a common feature in lung squamous cell carcinoma (LSCC), which could provide useful predictive and prognostic information. Objectives: This study aimed to investigate the effect of pretreatment pulmonary TN (PTN) on the prognosis of first-line anti-programmed cell death 1 (PD-1)/PD ligand 1 (PD-L1) inhibitor in advanced LSCC. Design: We conducted a retrospective study to analyze the association between the presence of PTN and clinical outcomes in advanced LSCC patients treated with anti-PD-1/PD-L1 inhibitors. Methods: Data from 240 eligible patients were collected from 27 hospitals across China between 2016 and 2020. The presence of PTN was assessed using contrast-enhanced chest computed tomography (CT) imaging at baseline. We utilized the Cox proportional-hazards regression model to analyze the association between PTN and clinical outcomes. In addition, to account for potential confounding factors and ensure comparability between groups, we employed propensity score-matching (PSM) analysis. Results: In the overall patient cohort, the presence of PTN was 39.6%. The median follow-up duration was 20.3 months. The positive PTN group exhibited a notably inferior median progression-free survival (PFS; 6.5 months vs 8.6 months, p = 0.012) compared to the negative PTN group. Within the Cox proportional-hazards regression model, PTN emerged as an independent predictor of unfavorable PFS (hazard ratio (HR) = 1.354, 95% confidence interval (CI): 1.002-1.830, p = 0.049). After PSM, the median PFS for the positive PTN group (6.5 months vs 8.0 months, p = 0.027) remained worse than that of the negative PTN group. Multivariate analyses also further underscored that the presence of PTN independently posed a risk for shorter PFS (HR = 1.494, 95% CI: 1.056-2.112, p = 0.023). However, no statistically significant difference in overall survival was observed between the two groups. Conclusion: Our study suggests that the presence of PTN on baseline contrast-enhanced chest CT is a potential negative prognostic imaging biomarker for the outcome of anti-PD-1/PD-L1 inhibitor therapy in advanced LSCC. Further studies are warranted to validate these findings and explore the underlying mechanisms.

Predicting anti-PD-1/PD-L1 inhibitor treatment outcomes: pulmonary tumor necrosis in lung squamous cell carcinoma Our study focused on lung squamous cell carcinoma (LSCC) patients receiving first-line anti-PD-1/PD-L1 therapy. We explored the impact of a feature called pretreatment pulmonary tumor necrosis (PTN) on their prognosis. PTN was identified in 39.6% of patients using baseline chest CT scans. Results revealed that patients with PTN had a shorter time without disease progression (median PFS of 6.5 months compared to 8.6 months) and a higher risk of unfavorable outcomes. This suggests that PTN may serve as a negative prognostic imaging marker for anti-PD-1/PD-L1 therapy in advanced LSCC. Further research is needed to confirm and understand these findings better.

Nanoporous, Ultrastiff, and Transparent Plastic-like Polymer Hydrogels Enabled by Hydrogen Bonding-Induced Self-Assembly.

Most natural supporting tissues possess both exceptional mechanical strength, a significant amount of water, and the anisotropic structure, as well as nanoscale assembly. These properties are essential for biological processes, but have been challenging to emulate in synthetic materials. In an effort to achieve simultaneous improvement of these trade-off features, a hydrogen bonding-induced self-assembly strategy was introduced to create nanoporous plastic-like polymer hydrogels. Multiple hydrogen bonding-mediated networks and nanoporous orientation structures endow transparent hydrogels with remarkable mechanical robustness. They exhibit Young's modulus of up to 223.7 MPa and a breaking strength of up to 10.3 MPa, which are superior to those of most common polymer hydrogels. The uniform porous nanostructures of hydrogen-bonded hydrogels contribute to a significantly larger specific surface area compared to conventional hydrogels. This allows for the retention of high mechanical properties in environments with a high water content of 70 wt %. A rubbery stage is observed during the heating process, which can reverse and reshape the manufacture of objects with various desired 2D or 3D shapes using techniques such as origami and kirigami. Finally, as a proof-of-concept, the outstanding mechanical properties of poly(MAA-co-AA-co-NVCL) hydrogel, combined with its high water content, make it suitable for applications such as smart temperature monitors, multilevel information anticounterfeiting, and artificial muscles.

Pharmacological Inhibition of TXNRD1 by a Small Molecule Flavonoid Butein Overcomes Cisplatin Resistance in Lung Cancer Cells.

Mammalian cytosolic selenoprotein thioredoxin reductase (TXNRD1) is crucial for maintaining the reduced state of cellular thioredoxin 1 (TXN1) and is commonly up-regulated in cancer cells. TXNRD1 has been identified as an effective target in cancer chemotherapy. Discovering novel TXNRD1 inhibitors and elucidating the cellular effects of TXNRD1 inhibition are valuable for developing targeted therapies based on redox regulation strategies. In this study, we demonstrated that butein, a plant-derived small molecule flavonoid, is a novel TXNRD1 inhibitor. We found that butein irreversibly inhibited recombinant TXNRD1 activity in a time-dependent manner. Using TXNRD1 mutant variants and LC-MS, we identified that butein modifies the catalytic cysteine (Cys) residues of TXNRD1. In cellular contexts, butein promoted the accumulation of reactive oxygen species (ROS) and exhibited cytotoxic effects in HeLa cells. Notably, we found that pharmacological inhibition of TXNRD1 by butein overcame the cisplatin resistance of A549 cisplatin-resistant cells, accompanied by increased cellular ROS levels and enhanced expression of p53. Taken together, the results of this study demonstrate that butein is an effective small molecule inhibitor of TXNRD1, highlighting the therapeutic potential of inhibiting TXNRD1 in platinum-resistant cancer cells.

Modulating Electrochemical Energy Storage and Multi-Spectra Defense of MXenes by Interfacial Dual-Filler Engineering.

MXenes have attracted growing interest in electrochemical energy storage owing to their high electronic conductivity and editable surface chemistry. Besides, rendering MXenes with spectrum defense properties further broadens their versatile applications. However, the development of MXenes suffers from weak van der Waal interaction-driven self-restacking that leads to random alignment and inferior interface microenvironments. Herein, a nacre-inspired MXene film is tailored by dual-filling of 2-ureido-4[1H]-pyrimidinone (UPy)-modified polyvinyl alcohol (PVA-UPy) and carbon nanotubes (CNTs). The dual-nanofillers engineering endows the nanocomposite film with a highly ordered structure (a Herman's order value of 0.838), a high mechanical strength (139.5 MPa), and continuous conductive pathways of both the ab plane and c-axis. As a proof-of-concept, the tailored nanocomposite film achieves a considerable capacitance of 508.2 F cm-3 and long-term cycling stability without performance degradation for 10 000 cycles. It is efficient for spectra defense in radar and infrared bands, displaying a high electromagnetic shielding capacity (19186 dB cm2 g-1) and a super-low infrared (IR) emissivity (0.16), with negligible performance decay after saving in the air for 1 year, responsible for the applications in specific and complex conditions. This interfacial dual-filler engineering concept showcases effective nanotechnology toward sustainable energy applications with a long lifetime and safety.

Hierarchical Magnetic Carbon Nanoflowers for Ultra-Efficient Electromagnetic Wave Absorption.

Porous carbon nanomaterials are widely applied in the electromagnetic wave absorption (EMWA) field. Among them, an emerging flower-like carbon nanomaterial, termed carbon nanoflowers (CNFs), has attracted tremendous research attention due to their unique hierarchical flower-like structure. However, the design of flower-like carbon nanomaterials with different magnetic cores for EMWA has rarely been reported. Herein, a general template method is proposed to achieve a set of high-quality magnetic CNFs, namely Co@Void@CNFs, CoNi@CNFs, and Ni@CNFs. The prepared magnetic CNFs have highly accessible surface area and internal space, rich heteroatom content, multi-scale pore system, and uniform and highly dispersed magnetic nanoparticles, as a result, deliver superior EMWA performance. Specifically, when the thickness is 2.6 mm, the Co@Void@CNFs exhibit a maximum refection loss (RLmax) of -56.6 dB and an effective absorption bandwidth (EAB) from 8.0 to 12.1 GHz covering the whole X band. The CoNi@CNFs have an RLmax of up to -57.6 dB and a wide EAB of 5.6 GHz at just 1.9 mm. For the Ni@CNFs, possess an ultra-broad EAB of 6.1 GHz, covering the entire Ku band at 2.0 mm. Overall, the hierarchical magnetic carbon nanoflowers proposed here offer new insights toward realizing multifunctional integrated carbon nanomaterials for EMWA.

Bridging Nickel-MOF and Copper Single Atoms/Clusters with H-Substituted Graphdiyne for the Tandem Catalysis of Nitrate to Ammonia.

Interfacial engineering of synergistic catalysts is one of the keys to achieving multiple proton-coupled electron transfer processes in nitrate-to-ammonia conversion. Herein, by joining ultrathin nickel-based metal-organic framework (denoted Ni-MOF) nanosheets with few-layered hydrogen-substituted graphdiyne-supported copper single atoms and clusters (denoted HsGDY@Cu), a tandem catalyst of Ni-MOFs@HsGDY@Cu with dual-active interfaces was developed for the concerted catalysis of nitrate-to-ammonia. In such a system, the sandwiched HsGDY layer could serve as a bridge to connect the coordinated unsaturated Ni2+ sites with Cu single atoms/clusters in a limited range of 0 to 3.6 nm. From Ni2+ to Cu, via the hydrogen spillover process, the hydrogen radicals (H⋅) generated at the unsaturated Ni2+ sites could migrate across HsGDY to the Cu sites to participate in the transformation of *HNO3 to NH3. From Cu to Ni2+, bypassing the higher reaction energy for *HNO3 formation on the Ni2+ sites, the NO2 - detached from the Cu sites could diffuse onto the unsaturated Ni2+ sites to form NH3 as well. The combined results make this hybrid a tandem catalyst with dual active sites for the catalysis of nitrate-to-ammonia conversion with improved Faradaic efficiency at lower overpotentials.

Intraspecific floral colour variation in three Pedicularis species.

Flower constancy describes the phenomenon that pollinators tend to successively visit flowers of a single species during foraging, reducing reproductive interference in natural communities. The extent of flower constancy is largely determined by the floral traits of co-flowering species. Both higher inter-specific and lower intraspecific differences of floral traits should contribute to a higher level of flower constancy. However, previous studies mainly focused on interspecific difference, and the intraspecific variation (consistency) of floral traits received much less attention. We hypothesise that selection may favour lower intraspecific floral trait variation in communities composed of multiple co-flowering congeners. We investigated the floral colour variation of three focal Pedicularis species that share pollinators in 19 communities composed of either single or multiple Pedicularis species. Colour was quantified using image-based colour analysis as perceived by pollinators. We found that most of the intrapopulation floral colour variation was below the colour discrimination threshold of bumblebees, implying strongly constrained by the visual selection by pollinators. Contrary to the hypothesis, there is no significant difference in intraspecific floral colour variation between different community contexts. It may be due to the relatively large interspecific floral colour differences of most co-flowering species. The influence of community context on intraspecific variation may be reflected in floral traits other than colours.

Up-regulated PLA2G10 in cancer impairs T cell infiltration to dampen immunity.

T cells are often absent from human cancer tissues during both spontaneously induced immunity and therapeutic immunotherapy, even in the presence of a functional T cell-recruiting chemokine system, suggesting the existence of T cell exclusion mechanisms that impair infiltration. Using a genome-wide in vitro screening platform, we identified a role for phospholipase A2 group 10 (PLA2G10) protein in T cell exclusion. PLA2G10 up-regulation is widespread in human cancers and is associated with poor T cell infiltration in tumor tissues. PLA2G10 overexpression in immunogenic mouse tumors excluded T cells from infiltration, resulting in resistance to anti-PD-1 immunotherapy. PLA2G10 can hydrolyze phospholipids into small lipid metabolites, thus inhibiting chemokine-mediated T cell mobility. Ablation of PLA2G10's enzymatic activity enhanced T cell infiltration and sensitized PLA2G10-overexpressing tumors to immunotherapies. Our study implicates a role for PLA2G10 in T cell exclusion from tumors and suggests a potential target for cancer immunotherapy.

A Metastructure Based on Amorphous Carbon for High Efficiency and Selective Solar Absorption.

Efficient solar thermal conversion is crucial for renewable clean energy technologies such as solar thermal power generation, solar thermophotovoltaic and seawater desalination. To maximize solar energy conversion efficiency, a solar selective absorber with tailored absorption properties designed for solar applications is indispensable. In this study, we propose a broadband selective absorber based on amorphous carbon (a-C) metamaterials that achieves high absorption in the ultraviolet (UV), visible (Vis) and near-infrared (NIR) spectral ranges. Additionally, through metal doping, the optical properties of carbon matrix materials can be modulated. We introduce Ti@a-C thin film into the nanostructure to enhance light absorption across most of the solar spectrum, particularly in the NIR wavelength band, which is essential for improving energy utilization. The impressive solar absorptivity and photothermal conversion efficiency reach 97.8% and 95.6%, respectively. Notably, these superior performances are well-maintained even at large incident angles with different polarized states. These findings open new avenues for the application of a-C matrix materials, especially in fields related to solar energy harvesting.

Molecular mechanisms of quetiapine bidirectional regulation of bipolar depression and mania based on network pharmacology and molecular docking: Evidence from computational biology.

BACKGROUND: Quetiapine monotherapy is recommended as the first-line option for acute mania and acute bipolar depression. However, the mechanism of action of quetiapine is unclear. Network pharmacology and molecular docking were employed to determine the molecular mechanisms of quetiapine bidirectional regulation of bipolar depression and mania. METHODS: Putative target genes for quetiapine were collected from the GeneCard, SwissTargetPrediction, and DrugBank databases. Targets for bipolar depression and bipolar mania were identified from the DisGeNET and GeneCards databases. A protein-protein interaction (PPI) network was generated using the String database and imported into Cytoscape. DAVID and the Bioinformatics platform were employed to perform the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses of the top 15 core targets. The drug-pathway-target-disease network was constructed using Cytoscape. Finally, molecular docking was performed to evaluate the interactions between quetiapine and potential targets. RESULTS: Targets for quetiapine actions against bipolar depression (126 targets) and bipolar mania (81 targets) were identified. Based on PPI and KEGG pathway analyses, quetiapine may affect bipolar depression by targeting the MAPK and PI3K/AKT insulin signaling pathways via BDNF, INS, EGFR, IGF1, and NGF, and it may affect bipolar mania by targeting the neuroactive ligand-receptor interaction signaling pathway via HTR1A, HTR1B, HTR2A, DRD2, and GRIN2B. Molecular docking revealed good binding affinity between quetiapine and potential targets. LIMITATIONS: Pharmacological experiments should be conducted to verify and further explore these results. CONCLUSIONS: Our findings suggest that quetiapine affects bipolar depression and bipolar mania through distinct biological core targets, and thus through different mechanisms. Furthermore, our results provide a theoretical basis for the clinical use of quetiapine and possible directions for new drug development.

A novel approach to evaluation of tumor response for advanced pulmonary adenocarcinoma using the intertumoral heterogeneity response score.

Treatment response and prognosis estimation in advanced pulmonary adenocarcinoma are challenged by the significant heterogeneity of the disease. The current Response Evaluation Criteria in Solid Tumors (RECIST) criteria, despite providing a basis for solid tumor response evaluation, do not fully encompass this heterogeneity. To better represent these nuances, we introduce the intertumoral heterogeneity response score (THRscore), a measure built upon and expanding the RECIST criteria. This retrospective study included patients with 3-10 measurable advanced lung adenocarcinoma lesions who underwent first-line chemotherapy or targeted therapy. The THRscore, derived from the coefficient of variation in size for each measurable tumor before and 4-6 weeks posttreatment, unveiled a correlation with patient outcomes. Specifically, a high THRscore was associated with shorter progression-free survival, lower tumor response rate, and a higher tumor mutation burden. These associations were further validated in an external cohort, confirming THRscore's effectiveness in stratifying patients based on progression risk and treatment response, and enhancing the utility of RECIST in capturing complex tumor behaviors in lung adenocarcinoma. These findings affirm the promise of THRscore as an enhanced tool for tumor response assessment in advanced lung adenocarcinoma, extending the RECIST criteria's utility.

Access to 2,4-Disubstituted Pyrrole-Based Polymer with Long-Wavelength and Stimuli-Responsive Properties via Copper-Catalyzed [3+2] Polycycloaddition.

Pyrrole-based polymers (PBPs), a type of fascinating functional polymers, play a crucial role in materials science. However, efficient synthetic strategies of PBPs with diverse structures are mainly focused on conjugated polypyrroles and still remain challenging. Herein, an atom and step economy protocol is described to access various 2,4-disubstituted PBPs by in situ formation of pyrrole core structure via copper-catalyzed [3+2] polycycloaddition of dialkynones and diisocyanoacetates. A series of PBPs is prepared with high molecular weight (Mw up to 18 200 Da) and moderate to good yield (up to 87%), which possesses a fluorescent emission located in the green to yellow light region. Blending the PBPs with polyvinyl alcohol, the stretchable composite films exhibit a significant strengthening of the mechanical properties (tensile stress up to 59 MPa, elongation at break >400%) and an unprecedented stress-responsive luminescence enhancement that over fourfold fluorescent emission intensity is maintained upon stretching up to 100%. On the basis of computational studies, the unique photophysical and mechanical properties are attributed to the substitution of carbonyl chromophores on the pyrrole unit.

Revealing Surface/Interface Chemistry of the Ordered Aramid Nanofiber/MXene Structure for Infrared Thermal Camouflage and Electromagnetic Interference Shielding.

The past decade has witnessed the advances of infrared (IR) thermal camouflage materials, but challenges remain in breaking the trade-off nature between emissivity and mechanical properties. In response, we identify the key role of a moderate reprotonation rate in the aramid nanofiber (ANF)/MXene film toward a surface-to-bulk alignment. Theoretical simulation demonstrates that the ordered ANF/MXene surface eliminates the local high electric field by field confinement and localization, responsible for the low IR emissivity. By scrutinizing the surface/interface chemistry, the processing optimization is achieved to develop an ordered and densely stacked ANF/MXene film, which features a low emissivity of 16%, accounting for sound IR thermal camouflage performances including a wide camouflage temperature range of 50-200 °C, a large reduction in radiation temperature from 200.5 to 63.6 °C, and long-term stability. This design also enables good mechanical performance such as a tensile strength of 190.8 MPa, a toughness of 12.1 MJ m-3, and a modulus of 7.9 GPa, responsible for better thermal camouflage applications. The tailor-made ANF/MXene film further attains an electromagnetic interference (EMI) shielding effectiveness (40.4 dB) in the X-band, manifesting its promise for IR stealth compatible EMI shielding applications. This work will shed light on the dynamic topology reconstruction of camouflage materials for boosting thermal management technology.

Monitoring soil moisture in winter wheat with crop water stress index based on canopy-air temperature time lag effect.

Crop water stress index (CWSI) has been widely used in soil moisture monitoring. However, the influence of the time lag effect between canopy temperature and air temperature on the accuracy of soil moisture monitoring with different CWSI models has not been further investigated. Therefore, based on the continuous record of canopy temperature and air temperature, this study explored the influence of canopy-air temperature hysteresis on the diagnosis of soil moisture with three CWSI models (CWSIT-theoretical, CWSIE-empirical, CWSIH-hybrid). The results show (1) the peak time of canopy temperature was ahead of that of air temperature, and the lag time varied under different soil moisture conditions. When the soil moisture was seriously deficient, the lag time decreased. However, from jointing-heading period to filling-ripening period, the lag time became longer. (2) The values of CWSIT, CWSIE, and CWSIH decreased when the time lag effect was considered. In jointing-heading period, heading-filling period, and filling-ripening period, CWSIT had the highest accuracy in soil moisture monitoring without the consideration of the time lag effect. When the time lag effect was considered, the monitoring accuracy of CWSIE and CWSIH was greatly improved and higher than that of CWSIT, while that of CWSIT was reduced. The findings provided a basis for further improving the accuracy of soil moisture monitoring with CWSI models.

Toward Ultrahigh-Rate Energy Storage of 3000 mV s-1 in Hollow Carbon: From Methodology to Surface-to-Bulk Synergy Insights.

Despite great efforts on economical and functionalized carbon materials, their scalable applications are still restricted by the unsatisfying energy storage capability under high-rate conditions. Herein, theoretical and methodological insights for surface-to-bulk engineering of multi-heteroatom-doped hollow porous carbon (HDPC), with subtly designed Zn(OH)F nanoarrays as the template are presented. This fine-tuned HDPC delivers an ultrahigh-rate energy storage capability even at a scan rate of 3000 mV s-1 (fully charged within 0.34 s). It preserves a superior capacitance of 234 F g-1 at a super-large current density of 100 A g-1 and showcases an ultralong cycling life without capacitance decay after 50 000 cycles. Through dynamic and theoretical analysis, the key role of in situ surface-modified heteroatoms and defects in decreasing the K+-adsorption/diffusion energy barrier is clarified, which cooperates with the porous conductive highways toward enhanced surface-to-bulk activity and kinetics. In situ Raman aids in visualizing the reversibly dynamic adsorption/releasing of the electrolyte ions on the tailored carbon structure during the charge/discharge process. The potential of the design concept is further evidenced by the enhanced performances in water-in-salt electrolytes. This surface-to-bulk nanotechnology opens the path for developing high-performance energy materials to better meet the practical requirements in the future.

Insights into characteristic motions and negative chemotaxis of the inanimate motor sensitive to sodium chloride.

Inanimate motors, driven by the difference in surface tension, provide platforms for studying the physics of characteristic motion and mimicking the complex behaviors of biological systems. However, it is challenging to endow inanimate motors with high autonomy, with an emphasis on simulating the behavior of living organisms in response to external stimuli. Herein, by applying sodium chloride (NaCl) as an external stimulus, we achieve the regulation of motion mode and chemotaxis in a self-propelled camphor system. We present a comprehensive surface/interface understanding of motion bifurcation with the increase of concentration NaCl, i.e., continuous motion to no motion via oscillatory motion. The features of motions (the speed and frequency) and the mechanisms are elucidated depending on the concentrations of NaCl and sodium dodecyl sulfate (SDS). Furthermore, the characteristic motion and chemotaxis to the salt stimulus are correlated to the dynamic breaking/reforming of the surface tension balance and gradient-type distribution phenomenon triggered by dynamic camphor dissolution, surfactant adsorption /diffusion and camphor-surfactant interaction. This work sheds light on the typical motions of inanimate motors and scrutinizes the synergy between dual additives, which will boost the design of advanced self-propelled systems with nonlinear characteristic motion.

B7-H1 agonists suppress the PI3K/AKT/mtor pathway by degrading p110γ and independently induce cell death.

The biological role of B7-H1 intrinsic signal is reportedly diverse and controversial, its signal pathway remains unclear. Although B7-H1 blocking antibodies were found to have agonist capacity, their binding features and agonist mechanisms need further investigation. Here, by constructing cell strains with full-length or truncated B7-H1, we found that B7-H1 functioned as a receptor to transmit cell death signal from PD-1 protein or anti-B7-H1s through its cytoplasmic domain. Specific binding to the IgV-like domain of B7-H1 was required for the downstream signal. Upon agonists interaction, B7-H1 regulated the degradation of phosphoinositide 3-kinases (PI3Ks) subunit p110γ, subsequently inhibited the PI3K/AKT/mTOR pathway, and significantly increased autophagy. Moreover, B7-H1 agonists also suppressed ubiquitylation in B7-H1+cells by reducing ubiquitin-activating enzyme (E1), eventually leading to cell death. Finally, we validated the receptor role of B7-H1 in multiple tumor cells and demonstrated that B7-H1 agonists could suppress tumor progression independent of T cells in vivo. Our findings revealed that B7-H1 agonists functions as a PI3K inhibitor and may offer new strategies for PI3K targeting therapy.

New Insight into the Electronic Effect for Cu Porphyrin Catalysts in Electrocatalytic of CO2 into CH4.

Perturbation of the copper (Cu) active site by electron manipulation is a crucial factor in determining the activity and selectivity of electrochemical carbon dioxide (CO2 ) reduction reaction (e-CO2 RR) in Cu-based molecular catalysts. However, much ambiguity is present concerning their electronic structure-function relationships. Here, three molecular Cu-based porphyrin catalysts with different electron densities at the Cu active site, Cu tetrakis(4-methoxyphenyl)porphyrin (Cu─T(OMe)PP), Cu tetraphenylporphyrin (Cu─THPP), and Cu tetrakis(4-bromophenyl)porphyrin (Cu─TBrPP), are prepared. Although all three catalysts exhibit e-CO2 RR activity and the same reaction pathway, their performance is significantly affected by the electronic structure of the Cu site. Theoretical and experimental investigations verify that the conjugated effect of ─OCH3 and ─Br groups lowers the highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbitals (LUMO) gap of Cu─T(OMe)PP and Cu─TBrPP, promoting faster electron transfer between Cu and CO2 , thereby improving their e-CO2 RR activity. Moreover, the high inductive effect of ─Br group reduces the electron density of Cu active site of Cu─TBrPP, facilitating the hydrolysis of the bound H2 O and thus creating a preferable local microenvironment, further enhancing the catalytic performance. This work provides new insights into the relationships between the substituent group characteristics with e-CO2 RR performance and is highly instructive for the design of efficient Cu-based e-CO2 RR electrocatalysts.

Reconfiguration, Welding, Reprogramming, and Complex Shape Transformation of An Optical Shape Memory Polymer Network Enabled by Patterned Secondary Crosslinking.

Stimuli-triggered generation of complicated 3D shapes from 2D strips or plates without using sophisticated molds is desirable and achieving such 2D-to-3D shape transformation in combination with shape reconfiguration, welding, and reprogramming on a single material is very challenging. Here, a convenient and facile strategy using the solution of a disulfide-containing diamine for patterned secondary crosslinking of an optical shape-memory polymer network is developed to integrate the above performances. The dangling thiolectones attached to the backbones react with the diamine in the solution-deposited region so that the secondary crosslinking may not only weld individual strips into assembled 3D shapes but also suppress the relaxation of the deformed polymer chains to different extents for shape reconfiguration or heating-induced complex 3D deformations. In addition, as the dynamic disulfide bonds can be thermally activated to erase the initial programming information and the excessive thiolectones are available for subsequent patterned crosslinking, the material also allows shape reprogramming. Combining welding with patterning treatment, it is further demonstrated that a gripper can be assembled and photothermally controlled to readily grasp an object.