Browse Articles

Gut microbiota structure in stingless bees is shaped by ontogeny, caste, and sex

Abstract The gut microbiota of eusocial bees functions as a dynamic system; however, despite extensive study in honey bees and bumble bees, it remains poorly understood in stingless bees. We used 16 S rRNA gene sequencing to characterize the gut microbiota of Melipona capixaba and Melipona mondury across developmental stages (larvae, nurses, and foragers), and across castes (workers and queens) and sexes (males and females) in M. mondury . We found that workers and males harbour richer communities. Workers are dominated by core bee-associated taxa, including Lactobacillus , Bifidobacterium , and Commensalibacter ; whereas males are enriched in transient and environmental genera such as Erwinia and Morganella . Nurse microbiota profile overlaps those of larvae, queens, and foragers. Larvae and queens harbour less diverse communities dominated by fermentative taxa. Both virgin and physogastric queens are dominated by Erysipelatoclostridium sp., indicating notable similarity regardless of physiological status. Predictive functional profiling is consistent with a model where worker and male microbiota are specialized for environmental resilience and oxidative metabolism, while larvae and queens are biased towards fermentation and detoxification. Our findings reveal that the microbiotas of M. capixaba and M. mondury constitute a highly plastic system, providing insights into how social structure interacts to calibrate the microbiota profile of individual colony members.

Polymorphism in Covalent Organic Frameworks Regulates Excited Dynamics for H ₂ O ₂ Photosynthesis Coupled With Biomass Valorization

ABSTRACT Polymorphism in covalent organic frameworks (COFs) offers a unique platform to decipher structure–property relationships, yet its impact on excited‐state dynamics remains unexplored. Herein, we construct two chemically identical but topologically distinct 1D and 2D COF polymorphs to correlate framework architecture with photocatalytic performance. Impressively, in H 2 O 2 photosynthesis coupled with furfuryl alcohol valorization, the 1D‐TBPP‐COF showed an exceptional H 2 O 2 generation rate (18.75 mmol g −1 h −1 ) and selective oxidation of furfuryl alcohol to high‐value 6‐hydroxy‐2H‐pyran‐3(6H)‐one (PN) with PN formation rate of 28.14 mmol·g −1 ·h −1 , substantially outperforming the 2D‐TBPP‐COF counterpart. Mechanistic investigations revealed that the intercalated dual‐chain edges in 1D‐TBPP‐COF impose steric constraints on aromatic ring rotation, effectively suppressing vibrational relaxation losses and prolonging the charge‐transfer state lifetime. In contrast, the conformationally flexible 2D‐TBPP‐COF permits greater rotational freedom, leading to non‐radiative energy dissipation. This work establishes polymorphism engineering as a powerful strategy to manipulate excited‐state dynamics in COFs for photocatalysis.

Weibull-based reliability integrated degradation framework in proton exchange membrane fuel cell system

Cobalt‐Catalyzed Reductive Asymmetric Dimerization of 1,3‐Enynes: Rapid Synthesis of Enantioenriched Skipped 1,3,6‐Trienes

ABSTRACT Enantioenriched skipped polyenes represent an important building block in natural products and bioactive molecules. Thus, it is of great importance for developing efficient methods for the synthesis of enantioenriched skipped polyenes yet challenging. To date, no example for direct access to skipped polyenes with controlled stereochemistry from simple and readily available starting materials has been developed. Herein, a cobalt‐catalyzed reductive asymmetric cross‐dimerization of 1,3‐enynes has been developed, affording the first rapid access to enantioenriched skipped 1,3,6‐trienes from readily available simple starting materials. Moreover, this protocol is amenable to enantioenriched skipped dienes by asymmetric reductive cross‐hydrodimerization of 1,3‐enynes with alkynes. Mechanistic investigations revealed a domino process by a chemoselective and non‐regioselective semi‐reduction of 1,3‐enynes to 1,3‐dienes followed by a chemo‐, regio‐, and enantioselective cross‐hydrodimerization of 1,3‐dienes with 1,3‐enynes. Notably, asymmetric reductive hydrodimerization of enynes represents the first example of synthesizing enantioenriched 1,3,6‐trienes, 1,3,5,8,10‐pentaenes, 1,4‐dienes from achiral starting materials.

Decentralized, centralized, and hierarchical coordination of residential DERs in three-phase unbalanced distribution networks: a comparative analysis

Electrostatic Modulation of Central Units Enables High‐Performance Fused‐Ring Trimeric Acceptors

ABSTRACT Fused‐ring trimeric acceptor benefits from both the high symmetry/planarity of small‐molecule acceptors and the large glass transition temperature of polymeric acceptors, making it highly potential to achieve organic solar cells (OSCs) with excellent power conversion efficiencies (PCEs) and long‐term stabilities simultaneously. However, due to the structural complexity of ring‐fused trimeric acceptor, conveniently tuning its optoelectronic properties remains a significant challenge. Herein, the first family of optically and electrostatically tunable fused‐ring trimeric acceptors (CH34, CH35, and CH36) is constructed by incorporating electron‐donating triazatruxene, electron‐neutral triphenylene and electron‐withdrawing tricycloquinazoline as central planes, respectively. All the trimeric acceptors maintain the intrinsic rigidity and planarity of molecular skeleton, which endow them with very small reorganization energies and weak electron–phonon coupling. Moreover, the quite different electrostatic properties of central cores exert significant effects on the energy levels distribution and light harvesting capacity of acceptors. Consequently, CH36 achieves a good PCE of 16.73%, representing the best performance among ring‐fused trimeric acceptors. Remarkably, CH36‐based ternary OSCs further render an excellent PCE of 20.48% along with substantially improved operational stability. Our work demonstrates the great potential of fused‐ring trimeric acceptor for realizing both highly efficient and stable organic photovoltaics.

Correction: Domain arrangement–driven immunogenicity of a computationally designed mRNA vaccine targeting PPE68, IrtA, and PE9 of Mycobacterium tuberculosis

Frontispiece: Artificial Transmembrane Channels for Selective Ascorbic Acid Transport and Bioorthogonal Signal Transduction

Phytochemicals from Tetraclinis articulata wood tar: HPLC-DAD-ESI-MS analysis, biological activities and in silico studies

Circular Photocaged mRNA for Light‐induced Late‐stage Activation of Translation

ABSTRACT mRNA is a new medical modality as vaccine and raises hopes to become a protein replacement agent. Despite notable advances in manufacturing, stabilization and modification, its short half‐life remains a major limitation. Circular RNA bears potential to solve this issue, as degradation of mRNA proceeds primarily from the 5′ and 3′ ends. However, circular RNAs normally lack a 5′ cap and are less efficiently translated. We present a strategy to circularize mRNA covalently via click chemistry by modifying the 5′ cap and the 3′ poly(A) tail with bioorthogonal functional groups. The resulting Cyclic Click Cap‐containing mRNA (CyCliCap‐mRNA) is translationally muted by a photocleavable protecting group. Upon irradiation by light, the photocleavable protecting group is removed and the respective linear Cap0‐mRNA released. We show that CyCliCap‐mRNA can be activated for efficient translation at late timepoints (24‐48 h post transfection) in HeLa cells, which is not possible with the respective linear mRNA. The light‐mediated opening releases linear mRNA with a native Cap0 and thus overcomes the problem of inefficient translation of circular RNAs.

Correction to “Poly(2‐Oxazoline)‐Based Functional Peptide Mimics: Eradicating MRSA Infections and Persisters While Alleviating Antimicrobial Resistance”

DPCT: dynamic part-center-based point cloud transformer

Functionalization‐Mediated Synthesis of Bridge‐Coordinated Fe Atoms on MoS ₂ Nanosheets for PEM Water Electrolyzers

ABSTRACT Transition metal chalcogenides are among the most promising platinum group metal‐free (PGM‐free) catalysts for hydrogen production in a proton exchange membrane water electrolyzer (PEMWE). However, achieving both high activity and long‐term stability remains a critical challenge for their practical deployment. Here, we report a functionalization‐mediated synthesis of molybdenum sulfide, containing bridge‐coordinated Fe atoms ( b ‐Fe‐MoS 2 ), achieving enhanced catalytic performance for the hydrogen evolution reaction (HER). Combined detailed spectroscopic and electrochemical characterizations revealed that cysteine functionalization promotes the anchoring of Fe atoms in a bridge‐like coordination environment on the MoS 2 nanosheets, resulting in tunable electron density near the Fe sites and improved robustness of the atomic sites, as supported by our operando and post‐mortem investigations. The experimental results are complemented with density functional theory (DFT) calculations revealing that the unique coordination environment of Fe atoms modulates the hydrogen adsorption free energy. When integrated in a 25 cm 2 catalyst‐coated membrane PEM water electrolyzer, b ‐Fe‐MoS 2 achieved remarkable performance, delivering 1.55 A cm −2 at 2 V and showed stable operation over 360 h following initial activation. These results demonstrate the effectiveness of the functionalization‐mediated approach for preparing robust HER catalysts and highlight the potential of bridge‐coordinated Fe–MoS 2 cathodes for PGM‐free PEM water electrolyzers.

AI usage patterns and self-rated critical thinking among Chinese college students: the moderating role of academic motivation

Abstract This study explores the associations between artificial intelligence (AI) usage patterns and perceived critical thinking among university students in China, with a focus on three types of AI use: Information Retrieval Use (IRU), Content Generation Use (CGU), and Text Revision Use (TRU). Grounded in Self-Determination Theory (SDT), the research investigates how academic motivation moderates these relationships. Cognitive Load Theory (CLT) provides an interpretive lens for understanding the observed patterns, though load was not directly measured. A cross-sectional survey was conducted with 342 undergraduate students, collecting data on their AI usage behaviors, academic motivation, and perceived critical thinking dispositions. The results reveal that IRU is positively associated with perceived critical thinking, while CGU shows a negative association. TRU showed no significant association. Regarding moderation effects, intrinsic motivation strengthened the positive association between IRU and perceived critical thinking, but, contrary to expectations, also amplified the negative association between CGU and perceived critical thinking. In contrast, extrinsic motivation buffered the negative association of CGU: at high levels of extrinsic motivation, the negative association between CGU and perceived critical thinking was entirely eliminated. These findings indicate that the cognitive correlates of AI use depend on both usage patterns and motivational factors. The study highlights the importance of considering both the type of AI use and students’ motivational orientation when designing educational strategies for AI integration in higher education.

Intrinsically Flame‐Retardant Liquid Crystal Elastomers With Flame‐Triggered Actuation Enabled by Main‐Chain P─C Bond Incorporation

ABSTRACT Liquid crystal elastomers (LCEs) are promising soft actuators, but their practical use is constrained by the incompatibility between fire safety and reversible actuation. Extrinsic flame‐retardant strategies can disrupt the liquid‐crystal organization and network integrity required for deformation, whereas existing phosphorus‐containing liquid crystal polymers (LCPs) are mainly rigid, aromatic thermoplastics designed for structural heat resistance rather than actuation. Here, we report a radical‐mediated P─H/ene step‐growth polymerization strategy for intrinsically flame‐retardant organophosphorus LCPs and LCEs using hypophosphorous acid and diene‐terminated mesogenic monomers. This main‐chain P─C bond‐forming strategy avoids rigid aromatic phosphorus units and affords phosphorus‐containing liquid‐crystalline systems with reduced phase‐transition temperatures together with a high phosphorus content of up to 6.8 wt.%. The resulting LCEs retain thermotropic liquid‐crystalline behavior, exhibit reversible thermoactuation, and show pronounced flame retardancy characterized by reduced heat release, self‐extinguishing behavior, and phosphorus‐promoted char formation. Notably, these organophosphorus LCEs also enable flame‐triggered actuation within only 0.4 s while preserving structural integrity and reversible function after flame exposure. This work establishes a practical molecular design route toward intrinsically flame‐retardant LCE actuators for thermally harsh environments.

MCDCNet: a multimodal cotton disease classification model for visually variable leaf symptoms under natural field conditions

Using Synthetic Glycans to Investigate Anti‐Glycan Antibodies and Explore Their Medical Potential

ABSTRACT The dynamic glycan layer that surrounds human and microbial cells plays an essential role in the immune system's capacity to maintain immune tolerance and equilibrium, fight pathogens and cancer. Endogenous anti‐glycan antibodies are an indispensable part of immune surveillance, identifying abnormal microbial glycans, viral glycoproteins, and altered tumor‐associated carbohydrate antigens. These glycans serve in turn as attractive targets for passive and active immunization strategies in a range of human diseases. The enormous complexity and structural diversity of glycans has made it very difficult to unlock their full biomedical potential. Recent advances in glycan synthesis, including automated solid‐phase assembly, chemoenzymatic strategies, and one‐pot approaches, enabled unprecedented access to well‐defined, homogenous structures. Hence, synthetic glycans of increasing structural complexity pave the way for a range of applications, from profiling endogenous antibody repertoires for biomarker discovery to therapeutic antibody development and vaccine design. Here, we summarize the strategies to utilize synthetic glycans for antibody development and their application in basic research and translational medicine. We outline how anti‐glycan antibodies are utilized for diagnostic and therapeutic purposes, while emphasizing the power of synthetic glycans and highlighting their potential in personalized medicine.

Biodiversity and natural capital in ecologically sensitive regions

Abstract Biodiversity and natural capital support economic systems, human well-being and climate resilience. Yet conservation and planning have focused mainly on visible ecosystems such as forests, wetlands and agricultural landscapes, while overlooking belowground biodiversity and the complex interactions between rural and rapidly urbanizing regions. This Collection analyses species, community and microbiome responses to environmental gradients, management interventions and climate constraints, and the effects of these responses on productivity, habitat quality, ecosystem functioning and natural capital. Several contributions highlight that climate-adapted seed sourcing in grand fir can maintain forest growth and carbon sequestration under changing moisture regimes, and that diverse multi-crops in boreal conditions raise biomass and net energy yields while lowering environmental pressures. Other studies introduce integrated indicators such as habitat quality indices for wetland waterfowl, soil functional networks in shaded coffee systems centred on total organic carbon, and multidimensional niche assessments for zooplankton communities. Together, these papers demonstrate complementary approaches for treating biodiversity as natural capital and for sustaining the ecosystem services that support human well-being, sustainable production and informed conservation and management decisions.

Aromatic Interaction‐Driven Adaptive Transformation of Macrocyclic Unimolecular Chloride Channels Into Nanopores

ABSTRACT Biological ion channels and pores frequently exhibit dynamic, concentration‐dependent adaptive assembly, yet synthetic systems that faithfully replicate this intriguing behavior remain rare. In this study, we present a novel class of tripeptide‐appended macrocyclic ion channels that undergo aromatic interaction‐driven adaptive transformation from unimolecular chloride channels into higher‐order nanopores. At low concentrations, analogues with aromatic tripeptide‐functionalized macrocycles ( MC‐F and MC‐W ) function as discrete and efficient chloride channels. Upon increasing the concentration, cooperative aromatic interactions among the tripeptide side chains promote their lateral self‐assembly into stable nanopores, enabling efficient transmembrane transport of small molecules, including carboxyfluorescein and glucose. In contrast, the aliphatic analogues ( MC‐A , MC‐L , and MC‐I ) remain restricted to unimolecular chloride channels. Single‐channel measurements combined with theoretical calculations further substantiate the structural stability and energetic preference of tetrameric and pentameric assemblies within lipid bilayers. Collectively, this work establishes cooperative aromatic interactions as a versatile and robust design principle for engineering adaptive artificial channels, thereby narrowing the functional gap between synthetic systems and the dynamic regulatory behavior of natural channels.

Correction: Faunal exploitation at the elephant hunting site of Lehringen, Germany, 125,000 years ago