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Tobacco ‘antisense’ lines with a stepwise reduction in Rubisco allowed a network approach to the regulation of photosynthesis, metabolism, allocation and growth
No full textOver 2 decades ago, antisense rbcS tobacco lines with a progressive decrease in Rubisco abundance allowed network analysis of the regulation of photosynthesis, metabolism, and whole plant allocation
Dynamic control of the three-phase boundary in hydrogel assisted TiO2-Graphdiyne photocatalysts for Ammonia production
No full textProducing NH3 via photocatalytic N2 reduction requires an ideal three-phase boundary (TPB) among N2 (gas), H2O (liquid), and a catalyst (solid). A promising strategy for developing TPB system involves photocatalyst passivation with temperature-responsive hydrogels that reversibly switch hydrophilic–hydrophobic characteristics. In this study, a self-controlling TPB system that combines a TiO2/graphdiyne photocatalyst with poly(N-isopropylacrylamide) (TiO2/GDY@PNIPAm) is explored. TiO2/GDY offers excellent solar absorption characteristics, efficient charge separation at the heterojunction, and abundant active sites for N2 reduction. Owing to a unique photothermal effect, TiO2/GDY generates a local temperature increase (39.5 °C) under irradiation. The temperature-responsive PNIPAm, utilized as an adaptive porous framework, enables dynamic regulation of interfacial wettability and gas transport within the TPB microenvironment through its hydrophilic–hydrophobic transition, thereby promoting selective N2 transport while inhibiting H2O transport. Under solar-light irradiation, the room temperature NH3 production rate of TiO2/GDY@PNIPAm (59.5 μmol/gh) exceeds that of TiO2 (0.46 μmol/gh). These findings provide valuable insights into photocatalyst design and local environment optimization using stimuli-responsive hydrogels toward green NH3 production
Regulierung der Promiskuitiven Katalyse durch Substratinduzierte Transiente Assemblierung
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Emergence of a Luttinger Liquid Phase in an Array of Chiral Molecules
No full textWe propose a robust platform for simulating chiral quantum magnetism using linear arrays of trapped asymmetric top molecules, specifically 1,2-propanediol (). By mapping the Stark-dressed rotational states onto an effective spin- subspace, we rigorously derive a generalized Heisenberg Hamiltonian governing the underlying many-body dynamics. Unlike standard solid-state models where the topological Dzyaloshinskii-Moriya Interaction (DMI) is introduced phenomenologically, we demonstrate that DMI emerges \textit{ab initio} from the molecular stereochemistry. Specifically, the interference between the transition dipole moments of heterochiral enantiomer pairs (L-R), which breaks inversion symmetry, generates a tunable DMI that stabilizes a Chiral Luttinger Liquid phase. Through a comprehensive phase-diagram analysis, we identify an optimal experimental regime characterized by intermolecular separations of and intermediate electric-field strengths . In this window, the system is protected from trivial field-polarized phases and exhibits a robust gapless spin-spiral texture. Our results establish 1,2-propanediol arrays as a versatile quantum simulator, providing a direct microscopic link between molecular chirality and topological many-body phases
Multiple redundant mechanisms account for the majority of gene silencing downstream of DNA methylation
No full textDNA methylation is a conserved epigenetic modification crucial for silencing genes and transposable elements (TEs). However, the mechanisms that cause silencing remain unclear, partly because methyl reader protein mutants in both plants and animals show minimal transcriptional changes. To explore the possibility of redundancy among these silencing mechanisms, we generated combinatorial mutants of H1.1, H1.2, ADCP1, MOM1, MBD2, MBD5, and MBD6 lacking key methyl readers and related silencing pathways. We observed massive derepression of genes and TEs at DNA methylated loci, showing that these pathways account for 73% of silencing compared to DNA methylation-free mutants. We also observed that immune response genes were upregulated, causing an imbalance between growth and defense. Loss of downstream silencing pathways further disrupted 3D genome organization, leading to increased euchromatin and heterochromatin interactions. These findings highlight the cooperative action of multiple downstream mechanisms in DNA methylation mediated silencing and genome organization
Debiasing Entrepreneurial Careers: A Field Experiment on Female Role Model Effects on Entrepreneurial Self-Efficacy and Early-Stage Career Choices
No full textWomen remain underrepresented not only as founders but also as employees – or "joiners" – in young and small firms, limiting their exposure to entrepreneurial environments that often serve as critical pathways to venture creation. To address this gap, we investigate whether introducing female entrepreneur role models in educational settings can shape young women's entrepreneurial self-efficacy and early career choices. Drawing on role congruity theory and social cognitive career theory (SCCT), we conducted a field experiment involving over 430 university students and 98 early-stage entrepreneurs. Using a pre-test/post-test design and longitudinal tracking of early career choices, we explore the causal effects of exogenously assigned female role models on students' decisions to join a young or small firm. We find that exposure to social interactions with female entrepreneurs significantly boosts female students' entrepreneurial self-efficacy. More importantly, women who were paired with a female entrepreneur were over 10% more likely to join a young firm after graduation compared to those assigned to a male entrepreneur. Mediation analysis confirms that entrepreneurial self-efficacy is a key mechanism linking exposure to same-sex role models with women's decision to join a young firm. These findings highlight the potential of targeted role model interventions to reduce gender disparities in entrepreneurial entry pathways and expand the diversity of entrepreneurial ecosystems