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Our changing information ecosystem for science and why it matters for effective science communication
Current information ecologies present unique opportunities to communicate science and engage diverse publics in science. Unfortunately, they also present unique challenges. Here, we outline how the public sphere for science is transforming as media evolve, and we connect these changes to the high-stakes issue context of COVID-19. We argue that scientific organizations’ struggles to adapt to evolving media are linked, in part, to asymmetries in which social media platforms prevent researchers from producing reliable data that could inform institutional change and improve science communication. This has been apparent in studies of echo chambers and filter bubbles. Producing a more usable evidence base, we conclude, will require that scholars a) obtain access to proprietary data, b) reconceptualize information ecologies as social systems, c) avoid ceding core research tasks to platforms, d) address ethical issues, and e) grapple with the urgency of moving forward productively.
Moderate-intensity continuous exercise preserves sleep quality, while high-intensity intermittent exercise disrupts it in female night-shift healthcare workers
15-PGDH inhibition preserves blood–brain barrier integrity and cognition
A novel technique utilizing enriched 15N2 to trace nitrogen transfer in grass and legume mixtures
Transformative community-engaged science: Strengthening relationships between science and society
There is a critical need to strengthen science–society relationships—especially with historically marginalized communities—if we are to better and more equitably manage complicated, intertwined, global challenges at the intersection of environment, health, equity, and well-being. Community-engaged science, which focuses on shared leadership and mutual benefit in scientific partnership with communities, has the potential to transform science, communities, and even society. Despite this promise, however, community-engaged science is not always transformative. Presentations and discussions at the 5th National Academies Science Communication Colloquium demonstrated the importance of creating structures, practices, and a culture of science engagement that prioritizes listening and learning from communities. Based on presentations at the colloquium, research publications, and our own experiences, we share a set of evidence-informed principles that are common to successful community-engaged science across many contexts: respect, humility, listening, reciprocity, mutuality, and reflexivity. We also offer steps the scientific community can take to advance and improve the transformative practice of community-engaged science as part of a productive ecosystem of scientific activities: evolving norms and culture, integrating community science into current systems, building incentives and structures to support community-engaged science, developing a workforce skilled in community engagement, and investing in a coordinated research-to-practice agenda.
Exploring the role of inflammation, immunity, and metabolism in colorectal cancer via mendelian randomization approach
Total synthesis and biological activity of “carbamorphine”: O-to-CH <sub>2</sub> replacement in the E-ring of the morphine core structure
Morphine is a µ-opioid receptor (MOR) agonist and potent analgesic. However, it displays several side effects including respiratory depression and addiction. Here, we show that a single heavy atom replacement in the morphine core structure (O to CH 2 exchange in the E-ring) prepared through a 15-step total synthesis displays a different pharmacological profile. The total synthesis features an intramolecular inverse electron-demand Diels−Alder cycloaddition and a stereoselective Giese radical addition to construct a quaternary carbon center. Unlike morphine, where the (–)-morphine enantiomer binds the MOR, both enantiomers of this “carba” variant, which we have named carbamorphine, possess activity as agonists of the MOR. Cell-based functional assays show that (+)-carbamorphine shows reduced G-protein as well as β-arrestin efficacy at the MOR. In mouse behavioral assays, (+)-carbamorphine exhibits MOR-selective antinociception while showing reduced respiratory depression and a lack of conditioned place preference at supratherapeutic doses. Overall, through a net “single-atom” change (i.e., O to CH 2 ) in the morphine framework, different pharmacological profiles have been realized. This work provides a basis for additional syntheses and the study of morphine analogs that incorporate atom changes in the core framework.
Immune cells mediate the association between the plasma lipidome and pancreatic cancer: a Mendelian randomization analysis
Barystatic sea level change observed by satellite gravimetry: 1993–2022
Using time-variable gravity fields determined from satellite laser ranging (SLR) and the Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow-On (GRACE-FO), we derive three decades of barystatic sea level (BSL) change estimates since 1993, providing a long record of satellite gravimetry-based BSL estimates comparable in duration to satellite altimetry. Over the 1993–2022 altimetry era, the BSL change rate is 1.75 ± 0.59 mm/y (2σ) as observed by SLR. The rate increases to 2.16 ± 0.59 mm/y (SLR) and 2.13 ± 0.38 mm/y (GRACE/-FO) over 2003–2022, mainly due to accelerated ice loss in Greenland since the 2000s. The remarkable agreement between SLR and GRACE/-FO estimates over the joint period cross-validates each other, suggesting that both work well in monitoring BSL changes. We also compare our satellite gravimetry estimates with the sum of individual mass change components (ice sheets, glaciers, and land water storage) obtained from multisource datasets (in situ, remote sensing and geophysical modeling). The differences are within 0.2 mm/y over the three decades, highlighting the global consistency of different techniques for observing Earth’s surface mass changes. Moreover, we reconcile the global mean sea level (GMSL) rise budget using reprocessed altimetry data and updated thermosteric sea level ensembles. From 1993 to 2022, the sum of thermosteric and SLR-based barystatic contributions (3.16 ± 0.64 mm/y) agrees well with altimetry-observed GMSL rate (3.22 ± 0.28 mm/y), suggesting that the GMSL rise budget can be closed within uncertainties over the last three decades.
Spatial separation between two sounds affects first-spike latencies of responses elicited by the sounds in the rat’s auditory midbrain neurons
Sleep duration and timing are associated with next-day physical activity: Insights from two large-scale wearable sensor studies
Sleep and physical activity (PA) are pillars of health. However, the temporal dynamics between these two behaviors remain poorly understood. This research aims to examine the independent and interactive between- and within-person associations of sleep duration and sleep onset timing on next-day PA duration in two large, longitudinal samples of adults under free-living conditions. In the primary study, participants (N = 19,963; 5,995,080 person-nights) wore a validated biometric device (WHOOP) for 1 y (01/09/2021 to 31/08/2022). Objective sleep and PA metrics were derived from the wrist-worn device. Generalized additive mixed models assessed between- and within-person associations between sleep and PA variables, adjusted for age, sex, Body Mass Index, weekday/weekend, seasonal effects, biometric feedback, and autocorrelated errors. Between participants, longer sleep duration and later sleep onset timing were associated with decreased moderate-to-vigorous PA (MVPA) and overall PA duration ( ps < 0.001). Within participants, sleeping shorter-than-usual and falling asleep earlier-than-usual were associated with increased next-day MVPA and overall PA, whereas sleeping longer-than-usual, or falling asleep later-than-usual, showed the opposite relationship ( ps < 0.001). Next-day MVPA duration was highest following earlier-than-usual sleep onset timing combined with one’s typical sleep duration. Results were consistent but smaller in magnitude in the external validation study (N = 5,898; 635,477 person-nights) using Fitbit data from the All of Us Research Program. Individuals may sacrifice time in one health behavior for time in the other. Interventions promoting exercise and holistic public health messaging should consider the temporal dynamics between sleep and next-day PA outcomes.
Dynamic reliability modeling and analysis of small modulus gear wear based on the Wiener process
Advanced synchrotron method reveals early molecular decomposition steps in a high-energy material
Extremely low-frequency electromagnetic field (ELF-EMF) enhances mitochondrial energy production in NARP cybrids
Abstract A mutation (m.8993T > G) in MT-ATP6 in mitochondrial DNA (mtDNA) causes the neuropathy, ataxia, retinitis pigmentosa (NARP) syndrome by impairing mitochondrial energy production. Extremely low-frequency electromagnetic field (ELF-EMF) suppresses mitochondrial oxidative phosphorylation (OXPHOS) Complex II and induces mitohormetic activation of mitochondrial OXPHOS activities. We examined the effects of ELF-EMF on normal cybrids carrying 100% wild-type mtDNA (2SA cybrids) and NARP cybrids carrying 40% wild-type and 60% mutant mtDNA (NARP3-2 cybrids). We found that ELF-EMF had no effect on the copy number of mtDNA either in 2SA or NARP3-2 cybrids, or the ratio of wild-type-to-mutant mtDNA in NARP3-2 cybrids. Instead, ELF-EMF increased the transcription of mtDNA and the transcription ratio of wild-type-to-mutant mtDNA in NARP3-2 cybrids. In addition, ELF-EMF increased the expression of mitochondrial OXPHOS proteins and the mitochondrial OXPHOS Complex V activity in NARP3-2 cybrids. ELF-EMF upregulated fission-promoting phosphorylation of DRP1, as well as the expression of fusion-promoting MFN1 and MFN2, in NARP3-2 cybrids. ELF-EMF also increased ATP production estimated by oxygen consumption rates (OCR) and by a biochemical assay in NARP3-2 cybrids. Hormetic activation of mitochondria by ELF-EMF is likely to be effective to ameliorate defective mitochondrial energy production in NARP and other mitochondrial diseases.
Prehistoric archives reveal evidence of predator loss and prey release in Caribbean reef fish communities
Understanding how humans have altered coral reef food webs remains challenging due to the absence of prehistoric baselines. Here, we use fish remains preserved in fossil and archaeological deposits from Panamá and the Dominican Republic to explore how Caribbean reef fish mortality patterns have changed over millennia. By quantifying accumulation rates of shark dermal denticles (scales) and bony fish otoliths (ear stones) in reef sediments, we assess relative fish abundance, while otolith size serves as a proxy for body size at death. Comparisons of these death assemblages suggest a 75% decline in shark-derived material and a 22% reduction in the sizes of human-targeted fishes—consistent with historical exploitation. This evidence of decline in large-bodied, higher trophic level fish remains coincided with a doubling in prey fish otolith accumulation and a 17% increase in their reconstructed body sizes. These patterns in time-averaged death assemblages align with effects of release from predation, documenting an often assumed (but rarely shown) cascading effect. In contrast, otoliths of predator-sheltered cryptobenthic fishes showed no change in either accumulation or size, suggesting that ‘‘bottom–up”environmental factors were not responsible for the observed changes. Together, these data indicate that pre-exploitation predator communities strongly controlled exposed prey fishes, but this “top–down” effect diminishes rapidly toward the food chain base, especially in predator-resistant groups. Understanding trophic cascades on Caribbean reefs requires studying systems before predator depletion.
Enhancing MPPT optimization with hybrid predictive control and adaptive P&O for better efficiency and power quality in PV systems
In vivo directed evolution of an ultrafast Rubisco from a semianaerobic environment imparts oxygen resistance
Carbon dioxide (CO 2 ) assimilation by the enzyme Ribulose-1,5-bisphosphate Carboxylase/Oxygenase (Rubisco) underpins biomass accumulation in photosynthetic bacteria and eukaryotes. Despite its pivotal role, Rubisco has a slow carboxylation rate ( k cat CO 2 ) and is competitively inhibited by oxygen (O 2 ). These traits impose limitations on photosynthetic efficiency, making Rubisco a compelling target for improvement. Interest in Form II Rubisco from Gallionellaceae bacteria, which comprise a dimer or hexamer of large subunits, arises from their nearly fivefold higher k cat CO 2 than the average Rubisco enzyme. As well as having a fast k cat CO 2 (25.8 s − 1 at 25 °C), we show that Gallionellaceae Rubisco (GWS1B) is extremely sensitive to O 2 inhibition, consistent with its evolution under semianaerobic environments. We therefore used an in vivo mutagenesis-mediated screening pipeline to evolve GWS1B over six rounds under oxygenic selection, identifying three catalytic point mutants with improved ambient carboxylation efficiency: Thr-29-Ala (T29A), Glu-40-Lys (E40K), and Arg-337-Cys (R337C). Full kinetic characterization showed that each substitution enhanced the CO 2 affinity of GWS1B under oxygenic conditions by subduing oxygen affinity, leading to 25% (E40K), 11% (T29A), and 8% (R337C) enhancements in carboxylation efficiency under ambient O 2 at 25 °C. By contrast, under the near anaerobic natural environment of Gallionellaceae , the carboxylation efficiency of each mutant was impaired ~16%. These findings demonstrate the efficacy of artificial directed evolution to access distinctive regions of catalytic space in Rubisco.
Efficacy of laryngeal mask airway versus endotracheal tube during total minimally invasive oesophagectomy: a randomized controlled trial
Tendencies toward triadic closure: Field experimental evidence
Empirical social networks are characterized by a high degree of triadic closure (i.e., transitivity, clustering): network neighbors of the same individual are also likely to be directly connected. It is unknown to what degree this results from dispositions to form such ties (i.e., to close open triangles) per se versus other processes such as homophily and more opportunities for exposure. These mechanisms are difficult to disentangle in many settings. On social media, however, they can be decomposed - and platforms frequently make decisions that depend on these distinct processes. Here, using a field experiment on social media, we randomize the existing network structure that a user faces when they are followed by a target account that we control. We then examine whether the user reciprocates this tie formation. Being randomly assigned to have an existing tie to an account that follows the target user increases tie formation by 35%. Through multiple control conditions, we attribute this effect specifically to a minimal cue that indicates the presence of a potential mutual follower. Theory suggests that triadic closure should be especially likely in open triads of strong ties, and accordingly we find larger effects when the subject has interacted more with the existing follower. These results indicate a substantial role for tendencies toward triadic closure, but one that is substantially smaller than what might be inferred from prior observational studies. Platforms and others may rely on these tendencies in encouraging tie formation, with broader implications for network structure and information diffusion in online networks.