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Fungal pathogens pose escalating challenges to global food security, as resistance has emerged against nearly all major fungicides used in agriculture. RNA-based antifungals offer a sustainable and environmentally friendly alternative for disease control, but their deployment is hindered by RNA instability under environmental conditions, especially in soil. In this study, we engineered two plant-beneficial soil bacteria-Bacillus subtilis (Gram-positive) and Pseudomonas putida (Gram-negative)-to produce double-stranded RNAs (dsRNAs) targeting fungal genes in the foliar and postharvest pathogen Botrytis cinerea and the soilborne pathogen Verticillium dahliae. We found that both bacterial species secrete RNA through extracellular vesicles (EVs) and that these RNAs are transported into fungal cells, demonstrating cross-kingdom RNA trafficking from bacteria to fungi. Application of dsRNA-containing bacterial EVs to plant leaves suppressed B. cinerea infection. In addition, direct treatment with dsRNA-producing bacteria protected both Arabidopsis thaliana and tomato plants from infections by B. cinerea and V. dahliae. Our findings establish beneficial bacteria as a scalable platform for continuous production and delivery of antifungal RNAs, enabling a cost-effective strategy for sustainable crop protection. 

Neuron Sandbox is a browser-based tool that helps middle school students grasp basic principles of neural computation. It simulates a linear threshold unit applied to binary decision problems, which students solve by adjusting the unit's threshold and/or weights. Although Neuron Sandbox provides extensive visualization aids, solving these problems is challenging for students who have not yet been exposed to algebra. We collected survey, video, and worksheet data from 21 seventh grade students in two sections of an AI elective, taught by the same teacher, that used Neuron Sandbox. We present a scaffolding strategy that proved effective at guiding these students to achieve mastery of these problems. While the amount of scaffolding required was more than we originally anticipated, by the end of the exercise students understood the computation that linear threshold units perform and were able to generalize their understanding of the worksheet’s solve for threshold strategy to also solve for weights. 

Spin chemistry of photogenerated spin-correlated radical pairs (SCRPs) offers a practical approach to control chemical reactions and molecular emissions by using weak magnetic fields. This capability to harness magnetic field effects (MFEs) paves the way for developing SCRPs-based molecular qubits. Here, we introduce a new series of donor–chiral bridge–acceptor (D−χ–A) molecules that demonstrate significant MFEs on fluorescence intensity and lifetime in solution at room temperature─critical for quantum sensing. By precisely tuning the donor site through torsional locking, distance extension, and planarization, we achieved remarkable control over key quantum properties, including field-response range and line width. In the most responsive systems, emission lifetimes increased by over 200%, and the total emission intensity was modulated by up to 30%. This level of tunability shows the power of synthetic spin chemistry. The rational design principle of optically addressable SCRP-based molecular systems, presented in this work, represents a major leap toward functional synthetic molecular qubits, advancing the field of molecular quantum technologies. 

The planetary model of the atom is alive and well in middle school science class—and in popular iconography—despite most educated adults’ awareness of its shortcomings. The model persists because it is easily visualized, intuitively understandable, and expresses important truths. Models don’t have to get everything right to be useful. Middle schoolers would be overwhelmed by a more correct description of electron orbitals as probability densities satisfying the Schrödinger equation. Better to just show orbitals as ellipses. In the current era, when immensely powerful AI technologies built on neural networks are rapidly disrupting the world, K-12 students need age-appropriate models of neural networks just as they need age-appropriate models of atoms. We suggest the linear threshold unit as the best model for introducing middle school students to neural computation, and we present an interactive tool, Neuron Sandbox, that facilitates their learning. 

Red-light absorbing photoredox catalysts offer potential advantages for large-scale reactions, expanding the range of usable substrates and facilitating bio-orthogonal applications. While many red-light absorbing/emitting fluorophores have been developed recently, functional red-light absorbing photoredox catalysts are scarce. Many photoredox catalysts rely on long-lived triplet excited states (triplets), which can efficiently engage in single electron transfer (SET) reactions with substrates. However, triplets of π-conjugated molecules are often significantly lower in energy than photogenerated singlet excited states (singlets). Combined with the inherent low energy of red light, this could limit the reductive/oxidative powers. Here, we introduce a series of sustainable heavy atom–free photoredox catalysts based on red-light absorbing dibenzo-fused BODIPY. The catalysts consist of two covalently linked units: a dibenzo-fused BODIPY fluorophore and an electron donor, arranged orthogonally. Excitation of the dibenzoBODIPY unit induces charge separation (CS) from the donor to the dibenzo-BODIPY unit, forming a radical pair (RP) state. Unlike the regular BODIPY counterparts, these catalysts do not form triplets. Instead, SET occurs from the high-energy singlet-born RP states, preventing energy loss and effectively utilizing the low-energy red light. The proximity of donor molecules allows efficient charge separation despite the CS being uphill in energy. The molecules demonstrate efficient catalysis of Atom Transfer Radical Addition (ATRA) reaction, yielding products with high yields ranging from 70% to 90%, while the molecule without a donor group does not exhibit catalytic activity. The mechanistic studies by transient absorption and electron paramagnetic resonance (EPR) spectroscopy methods support the proposed mechanism. The study presents a new molecular design strategy for converting noncatalytic fluorophores to effi-cient photoredox catalysts operating in the red spectral region. 

Spin chemistry of photogenerated spin-correlated radical pairs (SCRPs) offers a practical approach to control chemical reactions and molecular emissions using weak magnetic fields. This capability to harness magnetic field effects (MFEs) paves the way for developing SCRPs-based molecular qubits. Here, we introduce a new series of donor-chiral bridge-acceptor (D-χ-A) molecules that demonstrate significant MFEs on fluorescence intensity and lifetime in solution at room temperature – critical for quantum sensing. By precisely tuning the donor site through torsional locking, distance extension, and planarization, we achieved remarkable control over key quantum properties, including field-response range and linewidth. In the most responsive systems, emission lifetimes increased by over 200%, and total emission intensity was modulated by up to 30%. This level of tunability, and rational design principle of optically addressable molecular qubits, represents a major leap toward functional synthetic molecular qubits, advancing the field of molecular quantum technologies. 

BackgroundThe prevalence of human papillomavirus (HPV) and its related cancers is a major global concern. In the United States, routine HPV vaccination is recommended for youth aged 11 or 12 years. Despite HPV being the most common sexually transmitted infection and the vaccine’s proven efficacy, the vaccination rate among US youth remains below the recommended 80% completion rate. Mobile health (mHealth) interventions have demonstrated promise in improving health. Examining and synthesizing the current evidence about the impact of mHealth interventions on vaccination coverage in youth and intervention characteristics could guide future mHealth interventions aimed at mitigating the vaccination gap and disease burden. ObjectiveThis study aims to conduct a systematic review to assess the effectiveness of mHealth interventions on parental intent to vaccinate youth against HPV and youth’s vaccine uptake. MethodsWe searched empirical papers through databases including Google Scholar, PubMed, CINAHL, PsycINFO, and Cochrane Library. The inclusion criteria were the following: (1) published between January 2011 and December 2022; (2) using mHealth aimed to improve HPV vaccination rate; (3) targeted unvaccinated youth or their parents; and (4) measured HPV-related knowledge, vaccination intention, or vaccine uptake. Overall, 3 researchers screened and appraised the quality of the eligible papers using the Melnyk Levels of Evidence and the Cochrane Grading of Recommendations Assessment, Development, and Evaluation methodology. Disagreements in search results and result interpretation were resolved through consensus. ResultsOverall, 17 studies that met the inclusion criteria were included in the final review. Most studies were conducted in the United States (14/17, 82%), used a randomized controlled trial design (12/17, 71%), and adopted behavior change theories or a culture-centric approach (10/17, 59%). mHealth interventions included SMS text message reminders, motivational SMS text messages, computer-tailored or tablet-tailored interventions, smartphone apps, web-based tailored interventions, social media (Facebook) campaigns, digital videos, and digital storytelling interventions. Approximately 88% (15/17) of the mHealth interventions demonstrated positive effects on knowledge, intention, or behaviors related to HPV vaccination. Overall, 12% (2/17) reported limited or no intervention impact on vaccine uptake or vaccine series completion. Effective vaccine uptake was commonly seen in interventions based on behavior change theories and those that provided culturally relevant information. ConclusionsThis systematic review identified the impact of mHealth interventions among unvaccinated youth and their parents, which showed improvement in HPV-related knowledge, vaccination intention, or vaccine initiation. The interventions that incorporated theories and culture-centric approaches revealed the most promising results. Although these outcomes are encouraging, future studies are needed to investigate factors associated with the success of interventions using SMS text messaging or social media. More studies are also needed for a better understanding of the intervention elements that boost the responses of age-specific and ethnicity-specific populations. 

Abstract Migrating birds often fly in group formations during the daytime, whereas at night, it is generally presumed that they fly singly. However, it is difficult to quantify group behavior during nocturnal migration as there are few means of directly observing interactions among individuals. We employed an automated form of moonwatching to estimate percentages of birds that appear to migrate in groups during the night within the Central Flyway of North America. We compared percentages of birds in groups across the spring and fall and examined overnight temporal patterns of group behavior. We found groups were rare in both seasons, never exceeding 10% of birds observed, and were almost nonexistent during the fall. We also observed an overnight pattern of group behavior in the spring wherein groups were more commonly detected early in the night and again just before migration activity ceased. This finding may be related to changes in species composition of migrants throughout the night, or alternatively, it suggests that group formation may be associated with flocking activity on the ground as groups are most prevalent when birds begin and end a night of migration.