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Two covalent organic frameworks consisting of carbazolylene‐ethynylene shape‐persistent macrocycles with azine (MC‐COF‐1) or imine (MC‐COF‐2) linkages were synthesized via imine condensation. The obtained 2D frameworks are fully conjugated which imparts semiconducting properties. In addition, the frameworks showed high porosity with aligned accessible porous channels along the z axis, serving as an ideal platform for post‐synthetic incorporation of I₂into the channels to enable electrical conductivity. The resulting MC‐COF‐1 showed an electrical conductivity up to 7.8×10⁻⁴ S cm⁻¹at room temperature upon I₂doping with the activation energy as low as 0.09 eV. Furthermore, we demonstrated that the electrical properties of both MC‐COFs are switchable between electron‐conducting and insulating states by simply implementing doping‐regenerating cycles. The knowledge gained in this study opens new possibilities for the future development of tunable conductive 2D organic materials.

Two covalent organic frameworks consisting of carbazolylene‐ethynylene shape‐persistent macrocycles with azine (MC‐COF‐1) or imine (MC‐COF‐2) linkages were synthesized via imine condensation. The obtained 2D frameworks are fully conjugated which imparts semiconducting properties. In addition, the frameworks showed high porosity with aligned accessible porous channels along the z axis, serving as an ideal platform for post‐synthetic incorporation of I₂into the channels to enable electrical conductivity. The resulting MC‐COF‐1 showed an electrical conductivity up to 7.8×10⁻⁴ S cm⁻¹at room temperature upon I₂doping with the activation energy as low as 0.09 eV. Furthermore, we demonstrated that the electrical properties of both MC‐COFs are switchable between electron‐conducting and insulating states by simply implementing doping‐regenerating cycles. The knowledge gained in this study opens new possibilities for the future development of tunable conductive 2D organic materials.

Herein, the synthesis of Cu₃(HAB)_x(TATHB)_2‐x(HAB: hexaaminobenzene, TATHB: triaminotrihydroxybenzene) is reported. Synthetic improvement of Cu₃(TATHB)₂leads to a more crystalline framework with higher electrical conductivity value than previously reported. The improved crystallinity and analogous structure between TATHB and HAB enable the synthesis of Cu₃(HAB)_x(TATHB)_2‐xwith ligand compositions precisely controlled by precursor ratios. The electrical conductivity is tuned from 4.2 × 10⁻⁸to 2.9 × 10⁻⁵ S cm⁻¹by simply increasing the nitrogen content in the crystal lattice. Furthermore, computational calculation supports that the solid solution facilitates the band structure tuning. It is envisioned that the findings not only shed light on the ligand‐dependent structure–property relationship but create new prospects in synthesizing multicomponent electrically conductive metal‐organic frameworks (MOFs) for tailoring optoelectronic device applications.

Metastatic castration-resistant prostate cancer is typically lethal, exhibiting intrinsic or acquired resistance to second-generation androgen-targeting therapies and minimal response to immune checkpoint inhibitors¹. Cellular programs driving resistance in both cancer and immune cells remain poorly understood. We present single-cell transcriptomes from 14 patients with advanced prostate cancer, spanning all common metastatic sites. Irrespective of treatment exposure, adenocarcinoma cells pervasively coexpressed multiple androgen receptor isoforms, including truncated isoforms hypothesized to mediate resistance to androgen-targeting therapies^2,3. Resistance to enzalutamide was associated with cancer cell–intrinsic epithelial–mesenchymal transition and transforming growth factor-β signaling. Small cell carcinoma cells exhibited divergent expression programs driven by transcriptional regulators promoting lineage plasticity and HOXB5, HOXB6 and NR1D2 (refs.^4–6). Additionally, a subset of patients had high expression of dysfunction markers on cytotoxic CD8⁺T cells undergoing clonal expansion following enzalutamide treatment. Collectively, the transcriptional characterization of cancer and immune cells from human metastatic castration-resistant prostate cancer provides a basis for the development of therapeutic approaches complementing androgen signaling inhibition.

Porphyrinic metal–organic frameworks (PMOFs) are very appealing electrocatalytic materials, in part, due to their highly porous backbone, well‐defined and dispersed metal active sites, and their long‐range order. Herein a series of (Co)PCN222 (PCN: porous coordination network) (nano)particles with different sizes are successfully prepared by coordination modulation synthesis. These particles exhibit stability in 0.1mHClO₄electrolyte with no obvious particle size or compositional changes observed after being soaked for 3 days in the electrolyte or during electrocatalysis. This long‐term stability enables the in‐depth investigation into the electrocatalytic oxygen reduction, and it is further demonstrated that the (Co)PCN222 particle size correlates with its catalytic activity. Of the three particle sizes evaluated (characteristic length scales of 200, 500, and 1000 nm), the smallest size demonstrates the highest mass activity while the largest size has the highest surface area normalized activity. Together these results highlight the importance of determining the structural stability of framework catalysts and provide insights into the important roles of particle size, opening new avenues to investigate and improve the electrocatalytic performance of this class of framework material.

Meiotic crossovers facilitate chromosome segregation and create new combinations of alleles in gametes. Crossover frequency varies along chromosomes and crossover interference limits the coincidence of closely spaced crossovers. Crossovers can be measured by observing the inheritance of linked transgenes expressing different colors of fluorescent protein inArabidopsispollen tetrads. Here we establish DeepTetrad, a deep learning‐based image recognition package for pollen tetrad analysis that enables high‐throughput measurements of crossover frequency and interference in individual plants. DeepTetrad will accelerate the genetic dissection of mechanisms that control meiotic recombination.