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Effective chilling temperatures for dormancy release in extratropical forest trees increase from cold to warm regions
Seasonal dormancy in extratropical trees is a critical adaptation that synchronizes growth with favorable climatic conditions. Traditionally, the effective chilling temperatures (ECT) required for dormancy release have been assumed to be fixed, ranging between 0 and 10 °C, based largely on studies in cold climates. However, whether the ECT range varies across diverse climatic regions remains unclear, limiting our ability to predict tree responses to climate change. Here, we quantify ECT variation using controlled experiments on 14 species and long-term phenological observations of 65 species across a ~3,000 km latitudinal gradient in China. Our experimental results show that the estimated upper ECT threshold increases by 0.27 ± 0.06 °C per decreasing degree of latitude, indicating an expansion of the ECT range toward higher temperatures in warmer climates. Our modeling analysis of long-term phenological records supports this trend, showing a comparable increase of 0.18 ± 0.02 °C per decreasing degree of latitude. These findings provide empirical evidence of latitudinal variation in ECT, offering insights into the evolutionary adaptations in shaping tree seasonal growth across diverse climates, challenging the traditional view of a fixed 0 to 10 °C range. Incorporating this adaptive variation into vegetation models and management strategies is crucial for improving predictions of forest phenology, productivity, and resilience under climate warming.
O-acyltransferase genes involved in the production of volatile sex pheromones in <i> <i>Caenorhabditis elegans</i> </i>
Gene family expansions are critical for functional diversification, yet the contributions of paralogs to metabolic pathways are often unclear. In Caenorhabditis , the expanded O-acyltransferase (OAC) family—enzymes that transfer acyl groups to hydroxylated substrates—remains poorly characterized despite having been implicated in lipid metabolism. Using CRISPR-Cas9 mutagenesis, behavioral assays, gas chromatographic-mass spectral (GC-MS) analyses, and metabolomics, we systematically analyzed 59 OAC-family protein-coding genes to define their roles in regulating signaling molecules. We found that four adjacent paralogs ( oac-13, oac-16, oac-25, and oac-28 ) on chromosome I are required for synthesizing volatile sex pheromones—airborne signals critical for male mate-searching. Specifically, oac -13 and oac-16 are necessary for producing both major pheromone components, while the identical tandem paralogs oac-25 and oac-28 regulate the production of the later-eluting component in gas chromatography. Disruption of these genes reduced production of key pheromone components and impaired male attraction. Metabolomics revealed that oac-16 and other OACs also modulate the synthesis and secretion of nonvolatile ascaroside pheromones, indicating dual roles in chemical signaling. This work uncovers functional specialization within an expanded gene family, illustrating how redundancy and divergence enable adaptive evolution of communication systems.
Retraction for Mondal et al., IL-12 p40 monomer is different from other IL-12 family members to selectively inhibit IL-12Rβ1 internalization and suppress EAE
Combination antiviral and anti-inflammatory therapy mitigates persistent neurological deficits in mice post SARS-CoV-2 infection
Post-acute sequelae of COVID-19 (PASC) encompasses persistent neurological disease, including olfactory and cognitive dysfunction. The basis for this dysfunction is poorly understood. Here, we report neurological dysfunction for at least 120 d postinfection in mice infected with a virulent nonneurotropic mouse-adapted SARS-CoV-2. Long after recovery from nasal infection, we observed diminished tyrosine hydroxylase expression in olfactory bulb glomeruli and in substantia nigra. Similar changes were observed in brains of COVID-19 deceased patients. Vulnerability of dopaminergic neurons in these brain areas was accompanied by increased proinflammatory cytokines, and neurobehavioral changes. RNAseq analysis unveiled persistent microglia activation, similar to human neurodegenerative diseases. Treatment with antivirals (nirmatrelvir and molnupiravir) at the time of infection minimally prevented neurological abnormalities, consistent with patient data. In contrast, antivirals plus corticosteroids resulted in nearly complete recovery of neurological function. Remarkably, initiation of combined therapy even three days after infection improved outcomes. Together these results demonstrate that neurological dysfunction in SARS-CoV-2 infected mice resembles human neurodegenerative disease and indicate that minimizing inflammation early after SARS-CoV-2 infection may be critical for decreasing neurological PASC. The requirement for decreasing inflammation soon after infection may also explain why antiviral therapy has had inconsistent effects in patients.
Impact of dual-tasking and balance confidence on turns and transitions: a cross-sectional study in Parkinson’s disease
Abstract Background Mobility, cognitive processing, and balance confidence impairments can negatively affect functional mobility in people with Parkinson’s disease (PD). This study aimed to examine the effects of a cognitive dual-task on functional mobility during Timed Up and Go (TUG) sub-phases involving transitions and turns. A secondary aim was to explore whether balance confidence was associated with dual-task interference (DTI) on TUG total duration and sub-phases. Methods A cross-sectional design was employed. Participants completed TUG and TUG-COG (serial three subtractions) and inertial sensors recorded spatiotemporal data on transitions and turns. Paired samples t-tests and corresponding effect sizes (Cohen’s d) were used to compare TUG conditions. Multivariate linear regression assessed the association between balance confidence and DTI on total duration and sub-phases, controlling for gait speed and executive function. Results People with mild-to-moderate PD (N = 94, mean age: 68.7 years) completed TUG-COG 2.7 s slower than TUG (p < 0.001, d = 0.5, DTI = 22.9%). The cognitive task led to reduced performance across TUG sub-phases, with generally stronger effects observed in turning outcomes (d = 0.25–0.45) and comparatively smaller effects observed in postural transitions ( d = 0.02–0.38 ). Balance confidence explained variance in DTI for sit-to-stand duration (B = -−3.560, 95% CI [−5.499, −1.622], p < 0.001), whereas no effect was observed for other sub-phases. Conclusion Dual-tasking impaired nearly all components of the TUG, prolonging total duration and altering spatiotemporal characteristics of transitions and turns. Turning was more strongly impacted by dual-tasking than postural transitions, which has relevance for fall-prevention strategies. Together, the results of this study indicate that clinicians should prioritize turning during dual-task gait training and incorporate assessment of balance confidence to better capture functional capacity in transitional movements such as sit-to-stand.
Unveiling a proton-coupled electron-transfer mechanistic library of nitrate to ammonia via ultramicroelectrode-hyphenated mass spectrometry
For valuable ammonia synthesis and green nitrogen recycling, electrocatalytic nitrate reduction reaction (NO 3 RR) presents a sustainable alternative to the conventional Haber–Bosch process. The NO 3 RR involves intricate, multi-step proton-coupled electron transfers (PCET) featuring multiple nitrogen-oxygen intermediates and reaction branches. Unveiling this complex reaction library is crucial for rational tailoring of NO 3 RR for improved practical application, yet it remains a formidable challenge. Herein we present an in situ ultramicroelectrode-hyphenated mass spectrometry technique to systematically investigate the dynamic electrocatalytic NO 3 RR, using a cobalt-based molecular catalyst as a model system, and to decipher its mechanistic library under complex reaction environments (potential- and pH-dependent). Several key short-lived CoNO x H y intermediates were directly tracked and identified, experimentally revealing that the overall catalytic pathway of NO 3 RR proceeds through the intermediary [LCo-NO 3 ]→[LCo-NO 3 H] + →[LCo-NO 2 ] + → [LCo-NO 2 H] + → [LCo-NO] + → [LCo-NHOH] + → [LCo-NH] + to produce NH 3 , which were further validated by isotopic 15 N-labeling and collision-induced dissociation experiments. Combining theoretical simulations, a complete PCET-based mechanistic pathway was elucidated and distinguished from competing hydrogenation–deoxygenation mechanisms. Notably, a systematically interconnected electrochemical mechanistic library for NO 3 RR, visualized through heat maps, was constructed to illustrate intermediate selectivity across a broad potential-pH space. This platform underscores the promising potential of navigating the pathway prediction and regulation of complex reaction environments, thereby advancing the mechanistic understanding of NO 3 RR and other complicated electrocatalytic processes.
Exosomes derived from ADSCs suppress the fibrosis process of derma in secondary lymphedema
Imputing unjustified bulk density values to soils with biochar addition biases soil carbon sequestration estimates
Sustainable valorization of marine plastic residues via hydrothermal liquefaction for clean energy recovery
Abstract This study evaluates hydrothermal liquefaction (HTL) of real-world marine pollutant residues (MPR) composed of mixed plastics, organic matter, paper, and textiles. Using diatomaceous earth (DE) catalysis and aqueous-phase (AQ) recirculation, the effects on product yield, composition, and energy recovery were examined. Under optimized conditions (380 °C, 80 min, 10 wt% DE, RR = 6 mL g -1 ), a maximum bio crude yield of 51.6% with an HHV of 40.3 MJ kg -1 was achieved. Elemental, molecular, and thermal analyses (CHNS, GC–MS, FTIR, TGA) indicated improved hydrocarbon content and reduced oxygenation in the DE + AQ configuration. Net energy ratio (NER) calculations showed that the process can achieve energy-positive operation under conditions of elevated AQ recirculation temperature, highlighting the importance of heat integration. While these results demonstrate effective conversion of heterogeneous marine residues into energy-dense products, broader sustainability claims require further assessment of emissions, wastewater toxicity, and scale-up feasibility. The study provides experimentally grounded insights into HTL as a potential component of coastal waste valorization strategies.
Network structure shapes consensus dynamics through individual decisions
How do shared narratives emerge in decentralized online networks? Prior research using simplified group coordination tasks (e.g., face-naming) shows network structure shapes group consensus, but the underlying cognitive mechanisms remain unclear. Here, we examine how network structure influences the emergence and semantic content of shared narrative beliefs in experimental online social networks, using natural language processing measures and agent-based modeling. Media content with complex causal structure attenuates network structure effects by encouraging longer exploration of background knowledge. Yet network structure still shapes the narrative content communicated. An embedding-based narrative alignment measure shows that fully connected groups orient their interactions more toward communicating causes of an event, whereas locally connected networks emphasize the event’s effects. A group’s network structure also influences representational and language change in personal narratives: participants in fully connected networks showed the largest increase in causal language in personal narratives written after interaction, which also orient more around the narrative’s causal events.
Enhancing healthcare workers’ safety and well-being through a comprehensive qualitative analysis across hospital settings
Repeated losses of self-fertility shaped heterozygosity and polyploidy in yeast evolution
Evolutionary transitions in mating strategy have profound consequences for genetic variation and adaptation. In Saccharomyces cerevisiae , mating-type switching is a central feature of the life cycle that enables haploid cells to be self-fertile and mate with their own mitotic descendants (homothallism). Yet heterothallic isolates that have lost this ability are found across diverse niches, indicating that this trait is polymorphic. Here, we experimentally characterized loss of mating-type switching in a representative panel of strains. Analysis of 117 telomere-to-telomere genome assemblies revealed multiple independent loss-of-function mutations in the Ho endonuclease gene and structural variants in the silent HML and HMR cassettes, the three loci essential for switching. We estimated that at least 13 independent transitions from homothallism to heterothallism have occurred in the species history. Analysis of the HO genotype of 2,910 strains shows that at least 27% are heterothallic. We found that heterothallism is strongly associated with polyploidy and elevated genome-wide heterozygosity, although the strength of these associations varies between populations. Heterothallic isolates are most prevalent in domesticated and clinical clades, consistent with an origin linked to human-associated environments. However, they are also found, though less frequently, in natural niches. Signatures of recombination in HO sequences suggest that outcrossing contributed to the ecological and geographical distribution of the trait. Our findings reveal that mating-type switching has undergone repeated losses in S. cerevisiae evolution, with major consequences for genome architecture and ecological diversification.
Isorhamnetin inhibits mechanical stress-induced chondrocyte apoptosis through activation of the ROS/SRC/FOXO1 signaling pathway
Correction to Supporting Information for Li et al., p53 deficiency induces MTHFD2 transcription to promote cell proliferation and restrain DNA damage
A unified time-frequency foundation model for sleep decoding
Investigation of the functional hot-spot residues of an enzyme by real-time monitoring of the enzymatic reaction using NMR and computational approaches
Cholesterol-containing lipid crystals can directly stiffen the rat steatotic liver before fibrosis
Metabolic dysfunction–associated steatotic liver disease (MASLD) is characterized by liver steatosis with cardiometabolic risk factors like dyslipidemia. Patients may progress from steatosis alone to complications such as fibrosis, end-stage liver disease, and hepatocellular carcinoma. The cause of progression is unclear. We previously showed that liver stiffening can drive fibrosis. However, the mechanical contributions of hepatic lipid and especially cholesterol accumulation are not known. We used rat dietary models to investigate how lipid accumulation affects liver mechanics. Liver stiffness was measured using rheology and magnetic resonance elastography, and associations between stiffness and lipid droplets (LDs) or cholesterol-containing lipid crystals were measured by microindentation-visualization. Polarized light, confocal reflection, and cryo–electron microscopy were employed to assess crystal abundance and structure. LDs and crystals extracted from livers were embedded in fibrous tissue mimics to isolate mechanical effects away from inflammation or fibrosis. Methyl-β-cyclodextrin perfusion was performed to assess whether cholesterol depletion reduced crystal abundance and tissue stiffness. Increased hepatic cholesterol storage led to the formation of cholesterol-containing lipid crystals in the liver. Steatotic livers with crystals stiffened before fibrosis while steatotic livers without crystals did not stiffen or fibrose. Lipid crystals stiffened tissue mimics while LDs did not, suggesting that crystals directly cause stiffening. Cholesterol depletion reduced crystal abundance and reverted tissue stiffness to near controls without changing inflammation, suggesting key roles for cholesterol in tissue stiffening. Lipid crystals cause profibrogenic liver stiffening, connecting high dietary cholesterol to MASLD progression, and may be a target for new diagnostic tools and therapeutics for progressive MASLD.